Index: user/attilio/vmc-playground/sys/fs/tmpfs/tmpfs_fifoops.c =================================================================== --- user/attilio/vmc-playground/sys/fs/tmpfs/tmpfs_fifoops.c (revision 246331) +++ user/attilio/vmc-playground/sys/fs/tmpfs/tmpfs_fifoops.c (revision 246332) @@ -1,100 +1,99 @@ /* $NetBSD: tmpfs_fifoops.c,v 1.5 2005/12/11 12:24:29 christos Exp $ */ /*- * Copyright (c) 2005 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Julio M. Merino Vidal, developed as part of Google's Summer of Code * 2005 program. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * tmpfs vnode interface for named pipes. */ #include __FBSDID("$FreeBSD$"); #include #include #include -#include #include #include #include #include #include #include /* --------------------------------------------------------------------- */ static int tmpfs_fifo_kqfilter(struct vop_kqfilter_args *ap) { struct vnode *vp; struct tmpfs_node *node; vp = ap->a_vp; node = VP_TO_TMPFS_NODE(vp); switch (ap->a_kn->kn_filter){ case EVFILT_READ: node->tn_status |= TMPFS_NODE_ACCESSED; break; case EVFILT_WRITE: node->tn_status |= TMPFS_NODE_MODIFIED; break; } return fifo_specops.vop_kqfilter(ap); } /* --------------------------------------------------------------------- */ static int tmpfs_fifo_close(struct vop_close_args *v) { struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(v->a_vp); node->tn_status |= TMPFS_NODE_ACCESSED; tmpfs_update(v->a_vp); return fifo_specops.vop_close(v); } /* * vnode operations vector used for fifos stored in a tmpfs file system. */ struct vop_vector tmpfs_fifoop_entries = { .vop_default = &fifo_specops, .vop_close = tmpfs_fifo_close, .vop_reclaim = tmpfs_reclaim, .vop_access = tmpfs_access, .vop_getattr = tmpfs_getattr, .vop_setattr = tmpfs_setattr, .vop_kqfilter = tmpfs_fifo_kqfilter, }; Index: user/attilio/vmc-playground/sys/fs/tmpfs/tmpfs_vnops.c =================================================================== --- user/attilio/vmc-playground/sys/fs/tmpfs/tmpfs_vnops.c (revision 246331) +++ user/attilio/vmc-playground/sys/fs/tmpfs/tmpfs_vnops.c (revision 246332) @@ -1,1756 +1,1756 @@ /* $NetBSD: tmpfs_vnops.c,v 1.39 2007/07/23 15:41:01 jmmv Exp $ */ /*- * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Julio M. Merino Vidal, developed as part of Google's Summer of Code * 2005 program. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * tmpfs vnode interface. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include SYSCTL_DECL(_vfs_tmpfs); static volatile int tmpfs_rename_restarts; SYSCTL_INT(_vfs_tmpfs, OID_AUTO, rename_restarts, CTLFLAG_RD, __DEVOLATILE(int *, &tmpfs_rename_restarts), 0, "Times rename had to restart due to lock contention"); /* --------------------------------------------------------------------- */ static int tmpfs_lookup(struct vop_cachedlookup_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; int error; struct tmpfs_dirent *de; struct tmpfs_node *dnode; dnode = VP_TO_TMPFS_DIR(dvp); *vpp = NULLVP; /* Check accessibility of requested node as a first step. */ error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, cnp->cn_thread); if (error != 0) goto out; /* We cannot be requesting the parent directory of the root node. */ MPASS(IMPLIES(dnode->tn_type == VDIR && dnode->tn_dir.tn_parent == dnode, !(cnp->cn_flags & ISDOTDOT))); TMPFS_ASSERT_LOCKED(dnode); if (dnode->tn_dir.tn_parent == NULL) { error = ENOENT; goto out; } if (cnp->cn_flags & ISDOTDOT) { int ltype = 0; ltype = VOP_ISLOCKED(dvp); vhold(dvp); VOP_UNLOCK(dvp, 0); /* Allocate a new vnode on the matching entry. */ error = tmpfs_alloc_vp(dvp->v_mount, dnode->tn_dir.tn_parent, cnp->cn_lkflags, vpp); vn_lock(dvp, ltype | LK_RETRY); vdrop(dvp); } else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') { VREF(dvp); *vpp = dvp; error = 0; } else { de = tmpfs_dir_lookup(dnode, NULL, cnp); if (de != NULL && de->td_node == NULL) cnp->cn_flags |= ISWHITEOUT; if (de == NULL || de->td_node == NULL) { /* The entry was not found in the directory. * This is OK if we are creating or renaming an * entry and are working on the last component of * the path name. */ if ((cnp->cn_flags & ISLASTCN) && (cnp->cn_nameiop == CREATE || \ cnp->cn_nameiop == RENAME || (cnp->cn_nameiop == DELETE && cnp->cn_flags & DOWHITEOUT && cnp->cn_flags & ISWHITEOUT))) { error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, cnp->cn_thread); if (error != 0) goto out; /* Keep the component name in the buffer for * future uses. */ cnp->cn_flags |= SAVENAME; error = EJUSTRETURN; } else error = ENOENT; } else { struct tmpfs_node *tnode; /* The entry was found, so get its associated * tmpfs_node. */ tnode = de->td_node; /* If we are not at the last path component and * found a non-directory or non-link entry (which * may itself be pointing to a directory), raise * an error. */ if ((tnode->tn_type != VDIR && tnode->tn_type != VLNK) && !(cnp->cn_flags & ISLASTCN)) { error = ENOTDIR; goto out; } /* If we are deleting or renaming the entry, keep * track of its tmpfs_dirent so that it can be * easily deleted later. */ if ((cnp->cn_flags & ISLASTCN) && (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, cnp->cn_thread); if (error != 0) goto out; /* Allocate a new vnode on the matching entry. */ error = tmpfs_alloc_vp(dvp->v_mount, tnode, cnp->cn_lkflags, vpp); if (error != 0) goto out; if ((dnode->tn_mode & S_ISTXT) && VOP_ACCESS(dvp, VADMIN, cnp->cn_cred, cnp->cn_thread) && VOP_ACCESS(*vpp, VADMIN, cnp->cn_cred, cnp->cn_thread)) { error = EPERM; vput(*vpp); *vpp = NULL; goto out; } cnp->cn_flags |= SAVENAME; } else { error = tmpfs_alloc_vp(dvp->v_mount, tnode, cnp->cn_lkflags, vpp); } } } /* Store the result of this lookup in the cache. Avoid this if the * request was for creation, as it does not improve timings on * emprical tests. */ if ((cnp->cn_flags & MAKEENTRY) && cnp->cn_nameiop != CREATE) cache_enter(dvp, *vpp, cnp); out: /* If there were no errors, *vpp cannot be null and it must be * locked. */ MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp))); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_create(struct vop_create_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; MPASS(vap->va_type == VREG || vap->va_type == VSOCK); return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); } /* --------------------------------------------------------------------- */ static int tmpfs_mknod(struct vop_mknod_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; if (vap->va_type != VBLK && vap->va_type != VCHR && vap->va_type != VFIFO) return EINVAL; return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); } /* --------------------------------------------------------------------- */ static int tmpfs_open(struct vop_open_args *v) { struct vnode *vp = v->a_vp; int mode = v->a_mode; int error; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(vp)); node = VP_TO_TMPFS_NODE(vp); /* The file is still active but all its names have been removed * (e.g. by a "rmdir $(pwd)"). It cannot be opened any more as * it is about to die. */ if (node->tn_links < 1) return (ENOENT); /* If the file is marked append-only, deny write requests. */ if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE) error = EPERM; else { error = 0; vnode_create_vobject(vp, node->tn_size, v->a_td); } MPASS(VOP_ISLOCKED(vp)); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_close(struct vop_close_args *v) { struct vnode *vp = v->a_vp; MPASS(VOP_ISLOCKED(vp)); /* Update node times. */ tmpfs_update(vp); return (0); } /* --------------------------------------------------------------------- */ int tmpfs_access(struct vop_access_args *v) { struct vnode *vp = v->a_vp; accmode_t accmode = v->a_accmode; struct ucred *cred = v->a_cred; int error; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(vp)); node = VP_TO_TMPFS_NODE(vp); switch (vp->v_type) { case VDIR: /* FALLTHROUGH */ case VLNK: /* FALLTHROUGH */ case VREG: if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) { error = EROFS; goto out; } break; case VBLK: /* FALLTHROUGH */ case VCHR: /* FALLTHROUGH */ case VSOCK: /* FALLTHROUGH */ case VFIFO: break; default: error = EINVAL; goto out; } if (accmode & VWRITE && node->tn_flags & IMMUTABLE) { error = EPERM; goto out; } error = vaccess(vp->v_type, node->tn_mode, node->tn_uid, node->tn_gid, accmode, cred, NULL); out: MPASS(VOP_ISLOCKED(vp)); return error; } /* --------------------------------------------------------------------- */ int tmpfs_getattr(struct vop_getattr_args *v) { struct vnode *vp = v->a_vp; struct vattr *vap = v->a_vap; struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); tmpfs_update(vp); vap->va_type = vp->v_type; vap->va_mode = node->tn_mode; vap->va_nlink = node->tn_links; vap->va_uid = node->tn_uid; vap->va_gid = node->tn_gid; vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; vap->va_fileid = node->tn_id; vap->va_size = node->tn_size; vap->va_blocksize = PAGE_SIZE; vap->va_atime = node->tn_atime; vap->va_mtime = node->tn_mtime; vap->va_ctime = node->tn_ctime; vap->va_birthtime = node->tn_birthtime; vap->va_gen = node->tn_gen; vap->va_flags = node->tn_flags; vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ? node->tn_rdev : NODEV; vap->va_bytes = round_page(node->tn_size); vap->va_filerev = 0; return 0; } /* --------------------------------------------------------------------- */ /* XXX Should this operation be atomic? I think it should, but code in * XXX other places (e.g., ufs) doesn't seem to be... */ int tmpfs_setattr(struct vop_setattr_args *v) { struct vnode *vp = v->a_vp; struct vattr *vap = v->a_vap; struct ucred *cred = v->a_cred; struct thread *td = curthread; int error; MPASS(VOP_ISLOCKED(vp)); error = 0; /* Abort if any unsettable attribute is given. */ if (vap->va_type != VNON || vap->va_nlink != VNOVAL || vap->va_fsid != VNOVAL || vap->va_fileid != VNOVAL || vap->va_blocksize != VNOVAL || vap->va_gen != VNOVAL || vap->va_rdev != VNOVAL || vap->va_bytes != VNOVAL) error = EINVAL; if (error == 0 && (vap->va_flags != VNOVAL)) error = tmpfs_chflags(vp, vap->va_flags, cred, td); if (error == 0 && (vap->va_size != VNOVAL)) error = tmpfs_chsize(vp, vap->va_size, cred, td); if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL)) error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td); if (error == 0 && (vap->va_mode != (mode_t)VNOVAL)) error = tmpfs_chmod(vp, vap->va_mode, cred, td); if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL && vap->va_atime.tv_nsec != VNOVAL) || (vap->va_mtime.tv_sec != VNOVAL && vap->va_mtime.tv_nsec != VNOVAL) || (vap->va_birthtime.tv_sec != VNOVAL && vap->va_birthtime.tv_nsec != VNOVAL))) error = tmpfs_chtimes(vp, &vap->va_atime, &vap->va_mtime, &vap->va_birthtime, vap->va_vaflags, cred, td); /* Update the node times. We give preference to the error codes * generated by this function rather than the ones that may arise * from tmpfs_update. */ tmpfs_update(vp); MPASS(VOP_ISLOCKED(vp)); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_nocacheread(vm_object_t tobj, vm_pindex_t idx, vm_offset_t offset, size_t tlen, struct uio *uio) { vm_page_t m; int error, rv; VM_OBJECT_LOCK(tobj); m = vm_page_grab(tobj, idx, VM_ALLOC_WIRED | VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (m->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(tobj, idx, NULL, NULL)) { rv = vm_pager_get_pages(tobj, &m, 1, 0); if (rv != VM_PAGER_OK) { vm_page_lock(m); vm_page_free(m); vm_page_unlock(m); VM_OBJECT_UNLOCK(tobj); return (EIO); } } else vm_page_zero_invalid(m, TRUE); } VM_OBJECT_UNLOCK(tobj); error = uiomove_fromphys(&m, offset, tlen, uio); VM_OBJECT_LOCK(tobj); vm_page_lock(m); vm_page_unwire(m, TRUE); vm_page_unlock(m); vm_page_wakeup(m); VM_OBJECT_UNLOCK(tobj); return (error); } static __inline int tmpfs_nocacheread_buf(vm_object_t tobj, vm_pindex_t idx, vm_offset_t offset, size_t tlen, void *buf) { struct uio uio; struct iovec iov; uio.uio_iovcnt = 1; uio.uio_iov = &iov; iov.iov_base = buf; iov.iov_len = tlen; uio.uio_offset = 0; uio.uio_resid = tlen; uio.uio_rw = UIO_READ; uio.uio_segflg = UIO_SYSSPACE; uio.uio_td = curthread; return (tmpfs_nocacheread(tobj, idx, offset, tlen, &uio)); } static int tmpfs_mappedread(vm_object_t vobj, vm_object_t tobj, size_t len, struct uio *uio) { struct sf_buf *sf; vm_pindex_t idx; vm_page_t m; vm_offset_t offset; off_t addr; size_t tlen; char *ma; int error; addr = uio->uio_offset; idx = OFF_TO_IDX(addr); offset = addr & PAGE_MASK; tlen = MIN(PAGE_SIZE - offset, len); if (vobj == NULL) goto nocache; VM_OBJECT_LOCK(vobj); if (vobj->resident_page_count == 0 && vm_object_cache_is_empty(vobj)) { VM_OBJECT_UNLOCK(vobj); goto nocache; } lookupvpg: if (((m = vm_page_lookup(vobj, idx)) != NULL) && vm_page_is_valid(m, offset, tlen)) { if ((m->oflags & VPO_BUSY) != 0) { /* * Reference the page before unlocking and sleeping so * that the page daemon is less likely to reclaim it. */ vm_page_reference(m); vm_page_sleep(m, "tmfsmr"); goto lookupvpg; } vm_page_busy(m); VM_OBJECT_UNLOCK(vobj); error = uiomove_fromphys(&m, offset, tlen, uio); VM_OBJECT_LOCK(vobj); vm_page_wakeup(m); VM_OBJECT_UNLOCK(vobj); return (error); } else if (m != NULL && uio->uio_segflg == UIO_NOCOPY) { KASSERT(offset == 0, ("unexpected offset in tmpfs_mappedread for sendfile")); if ((m->oflags & VPO_BUSY) != 0) { /* * Reference the page before unlocking and sleeping so * that the page daemon is less likely to reclaim it. */ vm_page_reference(m); vm_page_sleep(m, "tmfsmr"); goto lookupvpg; } vm_page_busy(m); VM_OBJECT_UNLOCK(vobj); sched_pin(); sf = sf_buf_alloc(m, SFB_CPUPRIVATE); ma = (char *)sf_buf_kva(sf); error = tmpfs_nocacheread_buf(tobj, idx, 0, tlen, ma); if (error == 0) { if (tlen != PAGE_SIZE) bzero(ma + tlen, PAGE_SIZE - tlen); uio->uio_offset += tlen; uio->uio_resid -= tlen; } sf_buf_free(sf); sched_unpin(); VM_OBJECT_LOCK(vobj); if (error == 0) m->valid = VM_PAGE_BITS_ALL; vm_page_wakeup(m); VM_OBJECT_UNLOCK(vobj); return (error); } VM_OBJECT_UNLOCK(vobj); nocache: error = tmpfs_nocacheread(tobj, idx, offset, tlen, uio); return (error); } static int tmpfs_read(struct vop_read_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; struct tmpfs_node *node; vm_object_t uobj; size_t len; int resid; int error = 0; node = VP_TO_TMPFS_NODE(vp); if (vp->v_type != VREG) { error = EISDIR; goto out; } if (uio->uio_offset < 0) { error = EINVAL; goto out; } node->tn_status |= TMPFS_NODE_ACCESSED; uobj = node->tn_reg.tn_aobj; while ((resid = uio->uio_resid) > 0) { error = 0; if (node->tn_size <= uio->uio_offset) break; len = MIN(node->tn_size - uio->uio_offset, resid); if (len == 0) break; error = tmpfs_mappedread(vp->v_object, uobj, len, uio); if ((error != 0) || (resid == uio->uio_resid)) break; } out: return error; } /* --------------------------------------------------------------------- */ static int tmpfs_mappedwrite(vm_object_t vobj, vm_object_t tobj, size_t len, struct uio *uio) { vm_pindex_t idx; vm_page_t vpg, tpg; vm_offset_t offset; off_t addr; size_t tlen; int error, rv; error = 0; addr = uio->uio_offset; idx = OFF_TO_IDX(addr); offset = addr & PAGE_MASK; tlen = MIN(PAGE_SIZE - offset, len); if (vobj == NULL) { vpg = NULL; goto nocache; } VM_OBJECT_LOCK(vobj); if (vobj->resident_page_count == 0 && vm_object_cache_is_empty(vobj)) { VM_OBJECT_UNLOCK(vobj); vpg = NULL; goto nocache; } lookupvpg: - if (((vpg = vm_radix_lookup(&vobj->rtree, idx)) != NULL) && + if (((vpg = vm_page_lookup(vobj, idx)) != NULL) && vm_page_is_valid(vpg, offset, tlen)) { if ((vpg->oflags & VPO_BUSY) != 0) { /* * Reference the page before unlocking and sleeping so * that the page daemon is less likely to reclaim it. */ vm_page_reference(vpg); vm_page_sleep(vpg, "tmfsmw"); goto lookupvpg; } vm_page_busy(vpg); vm_page_undirty(vpg); VM_OBJECT_UNLOCK(vobj); error = uiomove_fromphys(&vpg, offset, tlen, uio); } else { vpg = vm_page_is_cached(vobj, idx); if (vpg != NULL) { mtx_lock(&vm_page_queue_free_mtx); if (vpg->object == vobj) vm_page_cache_free(vpg); mtx_unlock(&vm_page_queue_free_mtx); } VM_OBJECT_UNLOCK(vobj); vpg = NULL; } nocache: VM_OBJECT_LOCK(tobj); tpg = vm_page_grab(tobj, idx, VM_ALLOC_WIRED | VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (tpg->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(tobj, idx, NULL, NULL)) { rv = vm_pager_get_pages(tobj, &tpg, 1, 0); if (rv != VM_PAGER_OK) { vm_page_lock(tpg); vm_page_free(tpg); vm_page_unlock(tpg); error = EIO; goto out; } } else vm_page_zero_invalid(tpg, TRUE); } VM_OBJECT_UNLOCK(tobj); if (vpg == NULL) error = uiomove_fromphys(&tpg, offset, tlen, uio); else { KASSERT(vpg->valid == VM_PAGE_BITS_ALL, ("parts of vpg invalid")); pmap_copy_page(vpg, tpg); } VM_OBJECT_LOCK(tobj); if (error == 0) { KASSERT(tpg->valid == VM_PAGE_BITS_ALL, ("parts of tpg invalid")); vm_page_dirty(tpg); } vm_page_lock(tpg); vm_page_unwire(tpg, TRUE); vm_page_unlock(tpg); vm_page_wakeup(tpg); out: VM_OBJECT_UNLOCK(tobj); if (vpg != NULL) { VM_OBJECT_LOCK(vobj); vm_page_wakeup(vpg); VM_OBJECT_UNLOCK(vobj); } return (error); } static int tmpfs_write(struct vop_write_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; int ioflag = v->a_ioflag; boolean_t extended; int error = 0; off_t oldsize; struct tmpfs_node *node; vm_object_t uobj; size_t len; int resid; node = VP_TO_TMPFS_NODE(vp); oldsize = node->tn_size; if (uio->uio_offset < 0 || vp->v_type != VREG) { error = EINVAL; goto out; } if (uio->uio_resid == 0) { error = 0; goto out; } if (ioflag & IO_APPEND) uio->uio_offset = node->tn_size; if (uio->uio_offset + uio->uio_resid > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize) return (EFBIG); if (vn_rlimit_fsize(vp, uio, uio->uio_td)) return (EFBIG); extended = uio->uio_offset + uio->uio_resid > node->tn_size; if (extended) { error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid, FALSE); if (error != 0) goto out; } uobj = node->tn_reg.tn_aobj; while ((resid = uio->uio_resid) > 0) { if (node->tn_size <= uio->uio_offset) break; len = MIN(node->tn_size - uio->uio_offset, resid); if (len == 0) break; error = tmpfs_mappedwrite(vp->v_object, uobj, len, uio); if ((error != 0) || (resid == uio->uio_resid)) break; } node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | (extended ? TMPFS_NODE_CHANGED : 0); if (node->tn_mode & (S_ISUID | S_ISGID)) { if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID, 0)) node->tn_mode &= ~(S_ISUID | S_ISGID); } if (error != 0) (void)tmpfs_reg_resize(vp, oldsize, TRUE); out: MPASS(IMPLIES(error == 0, uio->uio_resid == 0)); MPASS(IMPLIES(error != 0, oldsize == node->tn_size)); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_fsync(struct vop_fsync_args *v) { struct vnode *vp = v->a_vp; MPASS(VOP_ISLOCKED(vp)); tmpfs_update(vp); return 0; } /* --------------------------------------------------------------------- */ static int tmpfs_remove(struct vop_remove_args *v) { struct vnode *dvp = v->a_dvp; struct vnode *vp = v->a_vp; int error; struct tmpfs_dirent *de; struct tmpfs_mount *tmp; struct tmpfs_node *dnode; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(dvp)); MPASS(VOP_ISLOCKED(vp)); if (vp->v_type == VDIR) { error = EISDIR; goto out; } dnode = VP_TO_TMPFS_DIR(dvp); node = VP_TO_TMPFS_NODE(vp); tmp = VFS_TO_TMPFS(vp->v_mount); de = tmpfs_dir_lookup(dnode, node, v->a_cnp); MPASS(de != NULL); /* Files marked as immutable or append-only cannot be deleted. */ if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) || (dnode->tn_flags & APPEND)) { error = EPERM; goto out; } /* Remove the entry from the directory; as it is a file, we do not * have to change the number of hard links of the directory. */ tmpfs_dir_detach(dvp, de); if (v->a_cnp->cn_flags & DOWHITEOUT) tmpfs_dir_whiteout_add(dvp, v->a_cnp); /* Free the directory entry we just deleted. Note that the node * referred by it will not be removed until the vnode is really * reclaimed. */ tmpfs_free_dirent(tmp, de); node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED; error = 0; out: return error; } /* --------------------------------------------------------------------- */ static int tmpfs_link(struct vop_link_args *v) { struct vnode *dvp = v->a_tdvp; struct vnode *vp = v->a_vp; struct componentname *cnp = v->a_cnp; int error; struct tmpfs_dirent *de; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(dvp)); MPASS(cnp->cn_flags & HASBUF); MPASS(dvp != vp); /* XXX When can this be false? */ node = VP_TO_TMPFS_NODE(vp); /* XXX: Why aren't the following two tests done by the caller? */ /* Hard links of directories are forbidden. */ if (vp->v_type == VDIR) { error = EPERM; goto out; } /* Cannot create cross-device links. */ if (dvp->v_mount != vp->v_mount) { error = EXDEV; goto out; } /* Ensure that we do not overflow the maximum number of links imposed * by the system. */ MPASS(node->tn_links <= LINK_MAX); if (node->tn_links == LINK_MAX) { error = EMLINK; goto out; } /* We cannot create links of files marked immutable or append-only. */ if (node->tn_flags & (IMMUTABLE | APPEND)) { error = EPERM; goto out; } /* Allocate a new directory entry to represent the node. */ error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node, cnp->cn_nameptr, cnp->cn_namelen, &de); if (error != 0) goto out; /* Insert the new directory entry into the appropriate directory. */ if (cnp->cn_flags & ISWHITEOUT) tmpfs_dir_whiteout_remove(dvp, cnp); tmpfs_dir_attach(dvp, de); /* vp link count has changed, so update node times. */ node->tn_status |= TMPFS_NODE_CHANGED; tmpfs_update(vp); error = 0; out: return error; } /* --------------------------------------------------------------------- */ /* * We acquire all but fdvp locks using non-blocking acquisitions. If we * fail to acquire any lock in the path we will drop all held locks, * acquire the new lock in a blocking fashion, and then release it and * restart the rename. This acquire/release step ensures that we do not * spin on a lock waiting for release. On error release all vnode locks * and decrement references the way tmpfs_rename() would do. */ static int tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp, struct vnode *tdvp, struct vnode **tvpp, struct componentname *fcnp, struct componentname *tcnp) { struct vnode *nvp; struct mount *mp; struct tmpfs_dirent *de; int error, restarts = 0; VOP_UNLOCK(tdvp, 0); if (*tvpp != NULL && *tvpp != tdvp) VOP_UNLOCK(*tvpp, 0); mp = fdvp->v_mount; relock: restarts += 1; error = vn_lock(fdvp, LK_EXCLUSIVE); if (error) goto releout; if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { VOP_UNLOCK(fdvp, 0); error = vn_lock(tdvp, LK_EXCLUSIVE); if (error) goto releout; VOP_UNLOCK(tdvp, 0); goto relock; } /* * Re-resolve fvp to be certain it still exists and fetch the * correct vnode. */ de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp); if (de == NULL) { VOP_UNLOCK(fdvp, 0); VOP_UNLOCK(tdvp, 0); if ((fcnp->cn_flags & ISDOTDOT) != 0 || (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.')) error = EINVAL; else error = ENOENT; goto releout; } error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp); if (error != 0) { VOP_UNLOCK(fdvp, 0); VOP_UNLOCK(tdvp, 0); if (error != EBUSY) goto releout; error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp); if (error != 0) goto releout; VOP_UNLOCK(nvp, 0); /* * Concurrent rename race. */ if (nvp == tdvp) { vrele(nvp); error = EINVAL; goto releout; } vrele(*fvpp); *fvpp = nvp; goto relock; } vrele(*fvpp); *fvpp = nvp; VOP_UNLOCK(*fvpp, 0); /* * Re-resolve tvp and acquire the vnode lock if present. */ de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp); /* * If tvp disappeared we just carry on. */ if (de == NULL && *tvpp != NULL) { vrele(*tvpp); *tvpp = NULL; } /* * Get the tvp ino if the lookup succeeded. We may have to restart * if the non-blocking acquire fails. */ if (de != NULL) { nvp = NULL; error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp); if (*tvpp != NULL) vrele(*tvpp); *tvpp = nvp; if (error != 0) { VOP_UNLOCK(fdvp, 0); VOP_UNLOCK(tdvp, 0); if (error != EBUSY) goto releout; error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp); if (error != 0) goto releout; VOP_UNLOCK(nvp, 0); /* * fdvp contains fvp, thus tvp (=fdvp) is not empty. */ if (nvp == fdvp) { error = ENOTEMPTY; goto releout; } goto relock; } } tmpfs_rename_restarts += restarts; return (0); releout: vrele(fdvp); vrele(*fvpp); vrele(tdvp); if (*tvpp != NULL) vrele(*tvpp); tmpfs_rename_restarts += restarts; return (error); } static int tmpfs_rename(struct vop_rename_args *v) { struct vnode *fdvp = v->a_fdvp; struct vnode *fvp = v->a_fvp; struct componentname *fcnp = v->a_fcnp; struct vnode *tdvp = v->a_tdvp; struct vnode *tvp = v->a_tvp; struct componentname *tcnp = v->a_tcnp; struct mount *mp = NULL; char *newname; int error; struct tmpfs_dirent *de; struct tmpfs_mount *tmp; struct tmpfs_node *fdnode; struct tmpfs_node *fnode; struct tmpfs_node *tnode; struct tmpfs_node *tdnode; MPASS(VOP_ISLOCKED(tdvp)); MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp))); MPASS(fcnp->cn_flags & HASBUF); MPASS(tcnp->cn_flags & HASBUF); /* Disallow cross-device renames. * XXX Why isn't this done by the caller? */ if (fvp->v_mount != tdvp->v_mount || (tvp != NULL && fvp->v_mount != tvp->v_mount)) { error = EXDEV; goto out; } /* If source and target are the same file, there is nothing to do. */ if (fvp == tvp) { error = 0; goto out; } /* If we need to move the directory between entries, lock the * source so that we can safely operate on it. */ if (fdvp != tdvp && fdvp != tvp) { if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { mp = tdvp->v_mount; error = vfs_busy(mp, 0); if (error != 0) { mp = NULL; goto out; } error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp, fcnp, tcnp); if (error != 0) { vfs_unbusy(mp); return (error); } ASSERT_VOP_ELOCKED(fdvp, "tmpfs_rename: fdvp not locked"); ASSERT_VOP_ELOCKED(tdvp, "tmpfs_rename: tdvp not locked"); if (tvp != NULL) ASSERT_VOP_ELOCKED(tvp, "tmpfs_rename: tvp not locked"); if (fvp == tvp) { error = 0; goto out_locked; } } } tmp = VFS_TO_TMPFS(tdvp->v_mount); tdnode = VP_TO_TMPFS_DIR(tdvp); tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp); fdnode = VP_TO_TMPFS_DIR(fdvp); fnode = VP_TO_TMPFS_NODE(fvp); de = tmpfs_dir_lookup(fdnode, fnode, fcnp); /* Entry can disappear before we lock fdvp, * also avoid manipulating '.' and '..' entries. */ if (de == NULL) { if ((fcnp->cn_flags & ISDOTDOT) != 0 || (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.')) error = EINVAL; else error = ENOENT; goto out_locked; } MPASS(de->td_node == fnode); /* If re-naming a directory to another preexisting directory * ensure that the target directory is empty so that its * removal causes no side effects. * Kern_rename gurantees the destination to be a directory * if the source is one. */ if (tvp != NULL) { MPASS(tnode != NULL); if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) || (tdnode->tn_flags & (APPEND | IMMUTABLE))) { error = EPERM; goto out_locked; } if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) { if (tnode->tn_size > 0) { error = ENOTEMPTY; goto out_locked; } } else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) { error = ENOTDIR; goto out_locked; } else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) { error = EISDIR; goto out_locked; } else { MPASS(fnode->tn_type != VDIR && tnode->tn_type != VDIR); } } if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) || (fdnode->tn_flags & (APPEND | IMMUTABLE))) { error = EPERM; goto out_locked; } /* Ensure that we have enough memory to hold the new name, if it * has to be changed. */ if (fcnp->cn_namelen != tcnp->cn_namelen || bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) { newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK); } else newname = NULL; /* If the node is being moved to another directory, we have to do * the move. */ if (fdnode != tdnode) { /* In case we are moving a directory, we have to adjust its * parent to point to the new parent. */ if (de->td_node->tn_type == VDIR) { struct tmpfs_node *n; /* Ensure the target directory is not a child of the * directory being moved. Otherwise, we'd end up * with stale nodes. */ n = tdnode; /* TMPFS_LOCK garanties that no nodes are freed while * traversing the list. Nodes can only be marked as * removed: tn_parent == NULL. */ TMPFS_LOCK(tmp); TMPFS_NODE_LOCK(n); while (n != n->tn_dir.tn_parent) { struct tmpfs_node *parent; if (n == fnode) { TMPFS_NODE_UNLOCK(n); TMPFS_UNLOCK(tmp); error = EINVAL; if (newname != NULL) free(newname, M_TMPFSNAME); goto out_locked; } parent = n->tn_dir.tn_parent; TMPFS_NODE_UNLOCK(n); if (parent == NULL) { n = NULL; break; } TMPFS_NODE_LOCK(parent); if (parent->tn_dir.tn_parent == NULL) { TMPFS_NODE_UNLOCK(parent); n = NULL; break; } n = parent; } TMPFS_UNLOCK(tmp); if (n == NULL) { error = EINVAL; if (newname != NULL) free(newname, M_TMPFSNAME); goto out_locked; } TMPFS_NODE_UNLOCK(n); /* Adjust the parent pointer. */ TMPFS_VALIDATE_DIR(fnode); TMPFS_NODE_LOCK(de->td_node); de->td_node->tn_dir.tn_parent = tdnode; TMPFS_NODE_UNLOCK(de->td_node); /* As a result of changing the target of the '..' * entry, the link count of the source and target * directories has to be adjusted. */ TMPFS_NODE_LOCK(tdnode); TMPFS_ASSERT_LOCKED(tdnode); tdnode->tn_links++; TMPFS_NODE_UNLOCK(tdnode); TMPFS_NODE_LOCK(fdnode); TMPFS_ASSERT_LOCKED(fdnode); fdnode->tn_links--; TMPFS_NODE_UNLOCK(fdnode); } } /* Do the move: just remove the entry from the source directory * and insert it into the target one. */ tmpfs_dir_detach(fdvp, de); if (fcnp->cn_flags & DOWHITEOUT) tmpfs_dir_whiteout_add(fdvp, fcnp); if (tcnp->cn_flags & ISWHITEOUT) tmpfs_dir_whiteout_remove(tdvp, tcnp); /* If the name has changed, we need to make it effective by changing * it in the directory entry. */ if (newname != NULL) { MPASS(tcnp->cn_namelen <= MAXNAMLEN); free(de->ud.td_name, M_TMPFSNAME); de->ud.td_name = newname; tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen); fnode->tn_status |= TMPFS_NODE_CHANGED; tdnode->tn_status |= TMPFS_NODE_MODIFIED; } /* If we are overwriting an entry, we have to remove the old one * from the target directory. */ if (tvp != NULL) { struct tmpfs_dirent *tde; /* Remove the old entry from the target directory. */ tde = tmpfs_dir_lookup(tdnode, tnode, tcnp); tmpfs_dir_detach(tdvp, tde); /* Free the directory entry we just deleted. Note that the * node referred by it will not be removed until the vnode is * really reclaimed. */ tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde); } tmpfs_dir_attach(tdvp, de); cache_purge(fvp); if (tvp != NULL) cache_purge(tvp); error = 0; out_locked: if (fdvp != tdvp && fdvp != tvp) VOP_UNLOCK(fdvp, 0); out: /* Release target nodes. */ /* XXX: I don't understand when tdvp can be the same as tvp, but * other code takes care of this... */ if (tdvp == tvp) vrele(tdvp); else vput(tdvp); if (tvp != NULL) vput(tvp); /* Release source nodes. */ vrele(fdvp); vrele(fvp); if (mp != NULL) vfs_unbusy(mp); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_mkdir(struct vop_mkdir_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; MPASS(vap->va_type == VDIR); return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); } /* --------------------------------------------------------------------- */ static int tmpfs_rmdir(struct vop_rmdir_args *v) { struct vnode *dvp = v->a_dvp; struct vnode *vp = v->a_vp; int error; struct tmpfs_dirent *de; struct tmpfs_mount *tmp; struct tmpfs_node *dnode; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(dvp)); MPASS(VOP_ISLOCKED(vp)); tmp = VFS_TO_TMPFS(dvp->v_mount); dnode = VP_TO_TMPFS_DIR(dvp); node = VP_TO_TMPFS_DIR(vp); /* Directories with more than two entries ('.' and '..') cannot be * removed. */ if (node->tn_size > 0) { error = ENOTEMPTY; goto out; } if ((dnode->tn_flags & APPEND) || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) { error = EPERM; goto out; } /* This invariant holds only if we are not trying to remove "..". * We checked for that above so this is safe now. */ MPASS(node->tn_dir.tn_parent == dnode); /* Get the directory entry associated with node (vp). This was * filled by tmpfs_lookup while looking up the entry. */ de = tmpfs_dir_lookup(dnode, node, v->a_cnp); MPASS(TMPFS_DIRENT_MATCHES(de, v->a_cnp->cn_nameptr, v->a_cnp->cn_namelen)); /* Check flags to see if we are allowed to remove the directory. */ if (dnode->tn_flags & APPEND || node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) { error = EPERM; goto out; } /* Detach the directory entry from the directory (dnode). */ tmpfs_dir_detach(dvp, de); if (v->a_cnp->cn_flags & DOWHITEOUT) tmpfs_dir_whiteout_add(dvp, v->a_cnp); /* No vnode should be allocated for this entry from this point */ TMPFS_NODE_LOCK(node); TMPFS_ASSERT_ELOCKED(node); node->tn_links--; node->tn_dir.tn_parent = NULL; node->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \ TMPFS_NODE_MODIFIED; TMPFS_NODE_UNLOCK(node); TMPFS_NODE_LOCK(dnode); TMPFS_ASSERT_ELOCKED(dnode); dnode->tn_links--; dnode->tn_status |= TMPFS_NODE_ACCESSED | \ TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED; TMPFS_NODE_UNLOCK(dnode); cache_purge(dvp); cache_purge(vp); /* Free the directory entry we just deleted. Note that the node * referred by it will not be removed until the vnode is really * reclaimed. */ tmpfs_free_dirent(tmp, de); /* Release the deleted vnode (will destroy the node, notify * interested parties and clean it from the cache). */ dnode->tn_status |= TMPFS_NODE_CHANGED; tmpfs_update(dvp); error = 0; out: return error; } /* --------------------------------------------------------------------- */ static int tmpfs_symlink(struct vop_symlink_args *v) { struct vnode *dvp = v->a_dvp; struct vnode **vpp = v->a_vpp; struct componentname *cnp = v->a_cnp; struct vattr *vap = v->a_vap; char *target = v->a_target; #ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */ MPASS(vap->va_type == VLNK); #else vap->va_type = VLNK; #endif return tmpfs_alloc_file(dvp, vpp, vap, cnp, target); } /* --------------------------------------------------------------------- */ static int tmpfs_readdir(struct vop_readdir_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; int *eofflag = v->a_eofflag; u_long **cookies = v->a_cookies; int *ncookies = v->a_ncookies; int error; ssize_t startresid; int cnt = 0; struct tmpfs_node *node; /* This operation only makes sense on directory nodes. */ if (vp->v_type != VDIR) return ENOTDIR; node = VP_TO_TMPFS_DIR(vp); startresid = uio->uio_resid; if (cookies != NULL && ncookies != NULL) { cnt = howmany(node->tn_size, sizeof(struct tmpfs_dirent)) + 2; *cookies = malloc(cnt * sizeof(**cookies), M_TEMP, M_WAITOK); *ncookies = 0; } if (cnt == 0) error = tmpfs_dir_getdents(node, uio, 0, NULL, NULL); else error = tmpfs_dir_getdents(node, uio, cnt, *cookies, ncookies); if (error == EJUSTRETURN) error = (uio->uio_resid != startresid) ? 0 : EINVAL; if (error != 0 && cnt != 0) free(*cookies, M_TEMP); if (eofflag != NULL) *eofflag = (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF); return error; } /* --------------------------------------------------------------------- */ static int tmpfs_readlink(struct vop_readlink_args *v) { struct vnode *vp = v->a_vp; struct uio *uio = v->a_uio; int error; struct tmpfs_node *node; MPASS(uio->uio_offset == 0); MPASS(vp->v_type == VLNK); node = VP_TO_TMPFS_NODE(vp); error = uiomove(node->tn_link, MIN(node->tn_size, uio->uio_resid), uio); node->tn_status |= TMPFS_NODE_ACCESSED; return error; } /* --------------------------------------------------------------------- */ static int tmpfs_inactive(struct vop_inactive_args *v) { struct vnode *vp = v->a_vp; struct tmpfs_node *node; MPASS(VOP_ISLOCKED(vp)); node = VP_TO_TMPFS_NODE(vp); if (node->tn_links == 0) vrecycle(vp); return 0; } /* --------------------------------------------------------------------- */ int tmpfs_reclaim(struct vop_reclaim_args *v) { struct vnode *vp = v->a_vp; struct tmpfs_mount *tmp; struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); tmp = VFS_TO_TMPFS(vp->v_mount); vnode_destroy_vobject(vp); cache_purge(vp); TMPFS_NODE_LOCK(node); TMPFS_ASSERT_ELOCKED(node); tmpfs_free_vp(vp); /* If the node referenced by this vnode was deleted by the user, * we must free its associated data structures (now that the vnode * is being reclaimed). */ if (node->tn_links == 0 && (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) { node->tn_vpstate = TMPFS_VNODE_DOOMED; TMPFS_NODE_UNLOCK(node); tmpfs_free_node(tmp, node); } else TMPFS_NODE_UNLOCK(node); MPASS(vp->v_data == NULL); return 0; } /* --------------------------------------------------------------------- */ static int tmpfs_print(struct vop_print_args *v) { struct vnode *vp = v->a_vp; struct tmpfs_node *node; node = VP_TO_TMPFS_NODE(vp); printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%x, links %d\n", node, node->tn_flags, node->tn_links); printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n", node->tn_mode, node->tn_uid, node->tn_gid, (intmax_t)node->tn_size, node->tn_status); if (vp->v_type == VFIFO) fifo_printinfo(vp); printf("\n"); return 0; } /* --------------------------------------------------------------------- */ static int tmpfs_pathconf(struct vop_pathconf_args *v) { int name = v->a_name; register_t *retval = v->a_retval; int error; error = 0; switch (name) { case _PC_LINK_MAX: *retval = LINK_MAX; break; case _PC_NAME_MAX: *retval = NAME_MAX; break; case _PC_PATH_MAX: *retval = PATH_MAX; break; case _PC_PIPE_BUF: *retval = PIPE_BUF; break; case _PC_CHOWN_RESTRICTED: *retval = 1; break; case _PC_NO_TRUNC: *retval = 1; break; case _PC_SYNC_IO: *retval = 1; break; case _PC_FILESIZEBITS: *retval = 0; /* XXX Don't know which value should I return. */ break; default: error = EINVAL; } return error; } static int tmpfs_vptofh(struct vop_vptofh_args *ap) { struct tmpfs_fid *tfhp; struct tmpfs_node *node; tfhp = (struct tmpfs_fid *)ap->a_fhp; node = VP_TO_TMPFS_NODE(ap->a_vp); tfhp->tf_len = sizeof(struct tmpfs_fid); tfhp->tf_id = node->tn_id; tfhp->tf_gen = node->tn_gen; return (0); } static int tmpfs_whiteout(struct vop_whiteout_args *ap) { struct vnode *dvp = ap->a_dvp; struct componentname *cnp = ap->a_cnp; struct tmpfs_dirent *de; switch (ap->a_flags) { case LOOKUP: return (0); case CREATE: de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp); if (de != NULL) return (de->td_node == NULL ? 0 : EEXIST); return (tmpfs_dir_whiteout_add(dvp, cnp)); case DELETE: tmpfs_dir_whiteout_remove(dvp, cnp); return (0); default: panic("tmpfs_whiteout: unknown op"); } } /* --------------------------------------------------------------------- */ /* * vnode operations vector used for files stored in a tmpfs file system. */ struct vop_vector tmpfs_vnodeop_entries = { .vop_default = &default_vnodeops, .vop_lookup = vfs_cache_lookup, .vop_cachedlookup = tmpfs_lookup, .vop_create = tmpfs_create, .vop_mknod = tmpfs_mknod, .vop_open = tmpfs_open, .vop_close = tmpfs_close, .vop_access = tmpfs_access, .vop_getattr = tmpfs_getattr, .vop_setattr = tmpfs_setattr, .vop_read = tmpfs_read, .vop_write = tmpfs_write, .vop_fsync = tmpfs_fsync, .vop_remove = tmpfs_remove, .vop_link = tmpfs_link, .vop_rename = tmpfs_rename, .vop_mkdir = tmpfs_mkdir, .vop_rmdir = tmpfs_rmdir, .vop_symlink = tmpfs_symlink, .vop_readdir = tmpfs_readdir, .vop_readlink = tmpfs_readlink, .vop_inactive = tmpfs_inactive, .vop_reclaim = tmpfs_reclaim, .vop_print = tmpfs_print, .vop_pathconf = tmpfs_pathconf, .vop_vptofh = tmpfs_vptofh, .vop_whiteout = tmpfs_whiteout, .vop_bmap = VOP_EOPNOTSUPP, }; Index: user/attilio/vmc-playground/sys/kern/uipc_shm.c =================================================================== --- user/attilio/vmc-playground/sys/kern/uipc_shm.c (revision 246331) +++ user/attilio/vmc-playground/sys/kern/uipc_shm.c (revision 246332) @@ -1,860 +1,860 @@ /*- * Copyright (c) 2006, 2011 Robert N. M. Watson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Support for shared swap-backed anonymous memory objects via * shm_open(2) and shm_unlink(2). While most of the implementation is * here, vm_mmap.c contains mapping logic changes. * * TODO: * * (1) Need to export data to a userland tool via a sysctl. Should ipcs(1) * and ipcrm(1) be expanded or should new tools to manage both POSIX * kernel semaphores and POSIX shared memory be written? * * (2) Add support for this file type to fstat(1). * * (3) Resource limits? Does this need its own resource limits or are the * existing limits in mmap(2) sufficient? */ #include __FBSDID("$FreeBSD$"); #include "opt_capsicum.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct shm_mapping { char *sm_path; Fnv32_t sm_fnv; struct shmfd *sm_shmfd; LIST_ENTRY(shm_mapping) sm_link; }; static MALLOC_DEFINE(M_SHMFD, "shmfd", "shared memory file descriptor"); static LIST_HEAD(, shm_mapping) *shm_dictionary; static struct sx shm_dict_lock; static struct mtx shm_timestamp_lock; static u_long shm_hash; #define SHM_HASH(fnv) (&shm_dictionary[(fnv) & shm_hash]) static int shm_access(struct shmfd *shmfd, struct ucred *ucred, int flags); static struct shmfd *shm_alloc(struct ucred *ucred, mode_t mode); static void shm_dict_init(void *arg); static void shm_drop(struct shmfd *shmfd); static struct shmfd *shm_hold(struct shmfd *shmfd); static void shm_insert(char *path, Fnv32_t fnv, struct shmfd *shmfd); static struct shmfd *shm_lookup(char *path, Fnv32_t fnv); static int shm_remove(char *path, Fnv32_t fnv, struct ucred *ucred); static int shm_dotruncate(struct shmfd *shmfd, off_t length); static fo_rdwr_t shm_read; static fo_rdwr_t shm_write; static fo_truncate_t shm_truncate; static fo_ioctl_t shm_ioctl; static fo_poll_t shm_poll; static fo_kqfilter_t shm_kqfilter; static fo_stat_t shm_stat; static fo_close_t shm_close; static fo_chmod_t shm_chmod; static fo_chown_t shm_chown; /* File descriptor operations. */ static struct fileops shm_ops = { .fo_read = shm_read, .fo_write = shm_write, .fo_truncate = shm_truncate, .fo_ioctl = shm_ioctl, .fo_poll = shm_poll, .fo_kqfilter = shm_kqfilter, .fo_stat = shm_stat, .fo_close = shm_close, .fo_chmod = shm_chmod, .fo_chown = shm_chown, .fo_flags = DFLAG_PASSABLE }; FEATURE(posix_shm, "POSIX shared memory"); static int shm_read(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags, struct thread *td) { return (EOPNOTSUPP); } static int shm_write(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags, struct thread *td) { return (EOPNOTSUPP); } static int shm_truncate(struct file *fp, off_t length, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; #ifdef MAC int error; #endif shmfd = fp->f_data; #ifdef MAC error = mac_posixshm_check_truncate(active_cred, fp->f_cred, shmfd); if (error) return (error); #endif return (shm_dotruncate(shmfd, length)); } static int shm_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, struct thread *td) { return (EOPNOTSUPP); } static int shm_poll(struct file *fp, int events, struct ucred *active_cred, struct thread *td) { return (EOPNOTSUPP); } static int shm_kqfilter(struct file *fp, struct knote *kn) { return (EOPNOTSUPP); } static int shm_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; #ifdef MAC int error; #endif shmfd = fp->f_data; #ifdef MAC error = mac_posixshm_check_stat(active_cred, fp->f_cred, shmfd); if (error) return (error); #endif /* * Attempt to return sanish values for fstat() on a memory file * descriptor. */ bzero(sb, sizeof(*sb)); sb->st_blksize = PAGE_SIZE; sb->st_size = shmfd->shm_size; sb->st_blocks = (sb->st_size + sb->st_blksize - 1) / sb->st_blksize; mtx_lock(&shm_timestamp_lock); sb->st_atim = shmfd->shm_atime; sb->st_ctim = shmfd->shm_ctime; sb->st_mtim = shmfd->shm_mtime; sb->st_birthtim = shmfd->shm_birthtime; sb->st_mode = S_IFREG | shmfd->shm_mode; /* XXX */ sb->st_uid = shmfd->shm_uid; sb->st_gid = shmfd->shm_gid; mtx_unlock(&shm_timestamp_lock); return (0); } static int shm_close(struct file *fp, struct thread *td) { struct shmfd *shmfd; shmfd = fp->f_data; fp->f_data = NULL; shm_drop(shmfd); return (0); } static int shm_dotruncate(struct shmfd *shmfd, off_t length) { vm_object_t object; vm_page_t m, ma[1]; vm_pindex_t idx, nobjsize; vm_ooffset_t delta; int base, rv; object = shmfd->shm_object; VM_OBJECT_LOCK(object); if (length == shmfd->shm_size) { VM_OBJECT_UNLOCK(object); return (0); } nobjsize = OFF_TO_IDX(length + PAGE_MASK); /* Are we shrinking? If so, trim the end. */ if (length < shmfd->shm_size) { /* * Disallow any requests to shrink the size if this * object is mapped into the kernel. */ if (shmfd->shm_kmappings > 0) { VM_OBJECT_UNLOCK(object); return (EBUSY); } /* * Zero the truncated part of the last page. */ base = length & PAGE_MASK; if (base != 0) { idx = OFF_TO_IDX(length); retry: - m = vm_radix_lookup(&object->rtree, idx); + m = vm_page_lookup(object, idx); if (m != NULL) { if ((m->oflags & VPO_BUSY) != 0 || m->busy != 0) { vm_page_sleep(m, "shmtrc"); goto retry; } } else if (vm_pager_has_page(object, idx, NULL, NULL)) { m = vm_page_alloc(object, idx, VM_ALLOC_NORMAL); if (m == NULL) { VM_OBJECT_UNLOCK(object); VM_WAIT; VM_OBJECT_LOCK(object); goto retry; } else if (m->valid != VM_PAGE_BITS_ALL) { ma[0] = m; rv = vm_pager_get_pages(object, ma, 1, 0); m = vm_page_lookup(object, idx); } else /* A cached page was reactivated. */ rv = VM_PAGER_OK; vm_page_lock(m); if (rv == VM_PAGER_OK) { vm_page_deactivate(m); vm_page_unlock(m); vm_page_wakeup(m); } else { vm_page_free(m); vm_page_unlock(m); VM_OBJECT_UNLOCK(object); return (EIO); } } if (m != NULL) { pmap_zero_page_area(m, base, PAGE_SIZE - base); KASSERT(m->valid == VM_PAGE_BITS_ALL, ("shm_dotruncate: page %p is invalid", m)); vm_page_dirty(m); vm_pager_page_unswapped(m); } } delta = ptoa(object->size - nobjsize); /* Toss in memory pages. */ if (nobjsize < object->size) vm_object_page_remove(object, nobjsize, object->size, 0); /* Toss pages from swap. */ if (object->type == OBJT_SWAP) swap_pager_freespace(object, nobjsize, delta); /* Free the swap accounted for shm */ swap_release_by_cred(delta, object->cred); object->charge -= delta; } else { /* Attempt to reserve the swap */ delta = ptoa(nobjsize - object->size); if (!swap_reserve_by_cred(delta, object->cred)) { VM_OBJECT_UNLOCK(object); return (ENOMEM); } object->charge += delta; } shmfd->shm_size = length; mtx_lock(&shm_timestamp_lock); vfs_timestamp(&shmfd->shm_ctime); shmfd->shm_mtime = shmfd->shm_ctime; mtx_unlock(&shm_timestamp_lock); object->size = nobjsize; VM_OBJECT_UNLOCK(object); return (0); } /* * shmfd object management including creation and reference counting * routines. */ static struct shmfd * shm_alloc(struct ucred *ucred, mode_t mode) { struct shmfd *shmfd; shmfd = malloc(sizeof(*shmfd), M_SHMFD, M_WAITOK | M_ZERO); shmfd->shm_size = 0; shmfd->shm_uid = ucred->cr_uid; shmfd->shm_gid = ucred->cr_gid; shmfd->shm_mode = mode; shmfd->shm_object = vm_pager_allocate(OBJT_DEFAULT, NULL, shmfd->shm_size, VM_PROT_DEFAULT, 0, ucred); KASSERT(shmfd->shm_object != NULL, ("shm_create: vm_pager_allocate")); VM_OBJECT_LOCK(shmfd->shm_object); vm_object_clear_flag(shmfd->shm_object, OBJ_ONEMAPPING); vm_object_set_flag(shmfd->shm_object, OBJ_NOSPLIT); VM_OBJECT_UNLOCK(shmfd->shm_object); vfs_timestamp(&shmfd->shm_birthtime); shmfd->shm_atime = shmfd->shm_mtime = shmfd->shm_ctime = shmfd->shm_birthtime; refcount_init(&shmfd->shm_refs, 1); #ifdef MAC mac_posixshm_init(shmfd); mac_posixshm_create(ucred, shmfd); #endif return (shmfd); } static struct shmfd * shm_hold(struct shmfd *shmfd) { refcount_acquire(&shmfd->shm_refs); return (shmfd); } static void shm_drop(struct shmfd *shmfd) { if (refcount_release(&shmfd->shm_refs)) { #ifdef MAC mac_posixshm_destroy(shmfd); #endif vm_object_deallocate(shmfd->shm_object); free(shmfd, M_SHMFD); } } /* * Determine if the credentials have sufficient permissions for a * specified combination of FREAD and FWRITE. */ static int shm_access(struct shmfd *shmfd, struct ucred *ucred, int flags) { accmode_t accmode; int error; accmode = 0; if (flags & FREAD) accmode |= VREAD; if (flags & FWRITE) accmode |= VWRITE; mtx_lock(&shm_timestamp_lock); error = vaccess(VREG, shmfd->shm_mode, shmfd->shm_uid, shmfd->shm_gid, accmode, ucred, NULL); mtx_unlock(&shm_timestamp_lock); return (error); } /* * Dictionary management. We maintain an in-kernel dictionary to map * paths to shmfd objects. We use the FNV hash on the path to store * the mappings in a hash table. */ static void shm_dict_init(void *arg) { mtx_init(&shm_timestamp_lock, "shm timestamps", NULL, MTX_DEF); sx_init(&shm_dict_lock, "shm dictionary"); shm_dictionary = hashinit(1024, M_SHMFD, &shm_hash); } SYSINIT(shm_dict_init, SI_SUB_SYSV_SHM, SI_ORDER_ANY, shm_dict_init, NULL); static struct shmfd * shm_lookup(char *path, Fnv32_t fnv) { struct shm_mapping *map; LIST_FOREACH(map, SHM_HASH(fnv), sm_link) { if (map->sm_fnv != fnv) continue; if (strcmp(map->sm_path, path) == 0) return (map->sm_shmfd); } return (NULL); } static void shm_insert(char *path, Fnv32_t fnv, struct shmfd *shmfd) { struct shm_mapping *map; map = malloc(sizeof(struct shm_mapping), M_SHMFD, M_WAITOK); map->sm_path = path; map->sm_fnv = fnv; map->sm_shmfd = shm_hold(shmfd); shmfd->shm_path = path; LIST_INSERT_HEAD(SHM_HASH(fnv), map, sm_link); } static int shm_remove(char *path, Fnv32_t fnv, struct ucred *ucred) { struct shm_mapping *map; int error; LIST_FOREACH(map, SHM_HASH(fnv), sm_link) { if (map->sm_fnv != fnv) continue; if (strcmp(map->sm_path, path) == 0) { #ifdef MAC error = mac_posixshm_check_unlink(ucred, map->sm_shmfd); if (error) return (error); #endif error = shm_access(map->sm_shmfd, ucred, FREAD | FWRITE); if (error) return (error); map->sm_shmfd->shm_path = NULL; LIST_REMOVE(map, sm_link); shm_drop(map->sm_shmfd); free(map->sm_path, M_SHMFD); free(map, M_SHMFD); return (0); } } return (ENOENT); } /* System calls. */ int sys_shm_open(struct thread *td, struct shm_open_args *uap) { struct filedesc *fdp; struct shmfd *shmfd; struct file *fp; char *path; Fnv32_t fnv; mode_t cmode; int fd, error; #ifdef CAPABILITY_MODE /* * shm_open(2) is only allowed for anonymous objects. */ if (IN_CAPABILITY_MODE(td) && (uap->path != SHM_ANON)) return (ECAPMODE); #endif if ((uap->flags & O_ACCMODE) != O_RDONLY && (uap->flags & O_ACCMODE) != O_RDWR) return (EINVAL); if ((uap->flags & ~(O_ACCMODE | O_CREAT | O_EXCL | O_TRUNC)) != 0) return (EINVAL); fdp = td->td_proc->p_fd; cmode = (uap->mode & ~fdp->fd_cmask) & ACCESSPERMS; error = falloc(td, &fp, &fd, 0); if (error) return (error); /* A SHM_ANON path pointer creates an anonymous object. */ if (uap->path == SHM_ANON) { /* A read-only anonymous object is pointless. */ if ((uap->flags & O_ACCMODE) == O_RDONLY) { fdclose(fdp, fp, fd, td); fdrop(fp, td); return (EINVAL); } shmfd = shm_alloc(td->td_ucred, cmode); } else { path = malloc(MAXPATHLEN, M_SHMFD, M_WAITOK); error = copyinstr(uap->path, path, MAXPATHLEN, NULL); /* Require paths to start with a '/' character. */ if (error == 0 && path[0] != '/') error = EINVAL; if (error) { fdclose(fdp, fp, fd, td); fdrop(fp, td); free(path, M_SHMFD); return (error); } fnv = fnv_32_str(path, FNV1_32_INIT); sx_xlock(&shm_dict_lock); shmfd = shm_lookup(path, fnv); if (shmfd == NULL) { /* Object does not yet exist, create it if requested. */ if (uap->flags & O_CREAT) { #ifdef MAC error = mac_posixshm_check_create(td->td_ucred, path); if (error == 0) { #endif shmfd = shm_alloc(td->td_ucred, cmode); shm_insert(path, fnv, shmfd); #ifdef MAC } #endif } else { free(path, M_SHMFD); error = ENOENT; } } else { /* * Object already exists, obtain a new * reference if requested and permitted. */ free(path, M_SHMFD); if ((uap->flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) error = EEXIST; else { #ifdef MAC error = mac_posixshm_check_open(td->td_ucred, shmfd, FFLAGS(uap->flags & O_ACCMODE)); if (error == 0) #endif error = shm_access(shmfd, td->td_ucred, FFLAGS(uap->flags & O_ACCMODE)); } /* * Truncate the file back to zero length if * O_TRUNC was specified and the object was * opened with read/write. */ if (error == 0 && (uap->flags & (O_ACCMODE | O_TRUNC)) == (O_RDWR | O_TRUNC)) { #ifdef MAC error = mac_posixshm_check_truncate( td->td_ucred, fp->f_cred, shmfd); if (error == 0) #endif shm_dotruncate(shmfd, 0); } if (error == 0) shm_hold(shmfd); } sx_xunlock(&shm_dict_lock); if (error) { fdclose(fdp, fp, fd, td); fdrop(fp, td); return (error); } } finit(fp, FFLAGS(uap->flags & O_ACCMODE), DTYPE_SHM, shmfd, &shm_ops); FILEDESC_XLOCK(fdp); if (fdp->fd_ofiles[fd] == fp) fdp->fd_ofileflags[fd] |= UF_EXCLOSE; FILEDESC_XUNLOCK(fdp); td->td_retval[0] = fd; fdrop(fp, td); return (0); } int sys_shm_unlink(struct thread *td, struct shm_unlink_args *uap) { char *path; Fnv32_t fnv; int error; path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); error = copyinstr(uap->path, path, MAXPATHLEN, NULL); if (error) { free(path, M_TEMP); return (error); } fnv = fnv_32_str(path, FNV1_32_INIT); sx_xlock(&shm_dict_lock); error = shm_remove(path, fnv, td->td_ucred); sx_xunlock(&shm_dict_lock); free(path, M_TEMP); return (error); } /* * mmap() helper to validate mmap() requests against shm object state * and give mmap() the vm_object to use for the mapping. */ int shm_mmap(struct shmfd *shmfd, vm_size_t objsize, vm_ooffset_t foff, vm_object_t *obj) { /* * XXXRW: This validation is probably insufficient, and subject to * sign errors. It should be fixed. */ if (foff >= shmfd->shm_size || foff + objsize > round_page(shmfd->shm_size)) return (EINVAL); mtx_lock(&shm_timestamp_lock); vfs_timestamp(&shmfd->shm_atime); mtx_unlock(&shm_timestamp_lock); vm_object_reference(shmfd->shm_object); *obj = shmfd->shm_object; return (0); } static int shm_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; int error; error = 0; shmfd = fp->f_data; mtx_lock(&shm_timestamp_lock); /* * SUSv4 says that x bits of permission need not be affected. * Be consistent with our shm_open there. */ #ifdef MAC error = mac_posixshm_check_setmode(active_cred, shmfd, mode); if (error != 0) goto out; #endif error = vaccess(VREG, shmfd->shm_mode, shmfd->shm_uid, shmfd->shm_gid, VADMIN, active_cred, NULL); if (error != 0) goto out; shmfd->shm_mode = mode & ACCESSPERMS; out: mtx_unlock(&shm_timestamp_lock); return (error); } static int shm_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; int error; error = 0; shmfd = fp->f_data; mtx_lock(&shm_timestamp_lock); #ifdef MAC error = mac_posixshm_check_setowner(active_cred, shmfd, uid, gid); if (error != 0) goto out; #endif if (uid == (uid_t)-1) uid = shmfd->shm_uid; if (gid == (gid_t)-1) gid = shmfd->shm_gid; if (((uid != shmfd->shm_uid && uid != active_cred->cr_uid) || (gid != shmfd->shm_gid && !groupmember(gid, active_cred))) && (error = priv_check_cred(active_cred, PRIV_VFS_CHOWN, 0))) goto out; shmfd->shm_uid = uid; shmfd->shm_gid = gid; out: mtx_unlock(&shm_timestamp_lock); return (error); } /* * Helper routines to allow the backing object of a shared memory file * descriptor to be mapped in the kernel. */ int shm_map(struct file *fp, size_t size, off_t offset, void **memp) { struct shmfd *shmfd; vm_offset_t kva, ofs; vm_object_t obj; int rv; if (fp->f_type != DTYPE_SHM) return (EINVAL); shmfd = fp->f_data; obj = shmfd->shm_object; VM_OBJECT_LOCK(obj); /* * XXXRW: This validation is probably insufficient, and subject to * sign errors. It should be fixed. */ if (offset >= shmfd->shm_size || offset + size > round_page(shmfd->shm_size)) { VM_OBJECT_UNLOCK(obj); return (EINVAL); } shmfd->shm_kmappings++; vm_object_reference_locked(obj); VM_OBJECT_UNLOCK(obj); /* Map the object into the kernel_map and wire it. */ kva = vm_map_min(kernel_map); ofs = offset & PAGE_MASK; offset = trunc_page(offset); size = round_page(size + ofs); rv = vm_map_find(kernel_map, obj, offset, &kva, size, VMFS_ALIGNED_SPACE, VM_PROT_READ | VM_PROT_WRITE, VM_PROT_READ | VM_PROT_WRITE, 0); if (rv == KERN_SUCCESS) { rv = vm_map_wire(kernel_map, kva, kva + size, VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); if (rv == KERN_SUCCESS) { *memp = (void *)(kva + ofs); return (0); } vm_map_remove(kernel_map, kva, kva + size); } else vm_object_deallocate(obj); /* On failure, drop our mapping reference. */ VM_OBJECT_LOCK(obj); shmfd->shm_kmappings--; VM_OBJECT_UNLOCK(obj); return (vm_mmap_to_errno(rv)); } /* * We require the caller to unmap the entire entry. This allows us to * safely decrement shm_kmappings when a mapping is removed. */ int shm_unmap(struct file *fp, void *mem, size_t size) { struct shmfd *shmfd; vm_map_entry_t entry; vm_offset_t kva, ofs; vm_object_t obj; vm_pindex_t pindex; vm_prot_t prot; boolean_t wired; vm_map_t map; int rv; if (fp->f_type != DTYPE_SHM) return (EINVAL); shmfd = fp->f_data; kva = (vm_offset_t)mem; ofs = kva & PAGE_MASK; kva = trunc_page(kva); size = round_page(size + ofs); map = kernel_map; rv = vm_map_lookup(&map, kva, VM_PROT_READ | VM_PROT_WRITE, &entry, &obj, &pindex, &prot, &wired); if (rv != KERN_SUCCESS) return (EINVAL); if (entry->start != kva || entry->end != kva + size) { vm_map_lookup_done(map, entry); return (EINVAL); } vm_map_lookup_done(map, entry); if (obj != shmfd->shm_object) return (EINVAL); vm_map_remove(map, kva, kva + size); VM_OBJECT_LOCK(obj); KASSERT(shmfd->shm_kmappings > 0, ("shm_unmap: object not mapped")); shmfd->shm_kmappings--; VM_OBJECT_UNLOCK(obj); return (0); } void shm_path(struct shmfd *shmfd, char *path, size_t size) { if (shmfd->shm_path == NULL) return; sx_slock(&shm_dict_lock); if (shmfd->shm_path != NULL) strlcpy(path, shmfd->shm_path, size); sx_sunlock(&shm_dict_lock); } Index: user/attilio/vmc-playground/sys/vm/vm_object.c =================================================================== --- user/attilio/vmc-playground/sys/vm/vm_object.c (revision 246331) +++ user/attilio/vmc-playground/sys/vm/vm_object.c (revision 246332) @@ -1,2498 +1,2496 @@ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_object.c 8.5 (Berkeley) 3/22/94 * * * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Authors: Avadis Tevanian, Jr., Michael Wayne Young * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ /* * Virtual memory object module. */ #include __FBSDID("$FreeBSD$"); #include "opt_vm.h" #include #include #include #include #include #include #include #include #include /* for curproc, pageproc */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static int old_msync; SYSCTL_INT(_vm, OID_AUTO, old_msync, CTLFLAG_RW, &old_msync, 0, "Use old (insecure) msync behavior"); static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags, int flags, boolean_t *clearobjflags, boolean_t *eio); static boolean_t vm_object_page_remove_write(vm_page_t p, int flags, boolean_t *clearobjflags); static void vm_object_qcollapse(vm_object_t object); static void vm_object_vndeallocate(vm_object_t object); /* * Virtual memory objects maintain the actual data * associated with allocated virtual memory. A given * page of memory exists within exactly one object. * * An object is only deallocated when all "references" * are given up. Only one "reference" to a given * region of an object should be writeable. * * Associated with each object is a list of all resident * memory pages belonging to that object; this list is * maintained by the "vm_page" module, and locked by the object's * lock. * * Each object also records a "pager" routine which is * used to retrieve (and store) pages to the proper backing * storage. In addition, objects may be backed by other * objects from which they were virtual-copied. * * The only items within the object structure which are * modified after time of creation are: * reference count locked by object's lock * pager routine locked by object's lock * */ struct object_q vm_object_list; struct mtx vm_object_list_mtx; /* lock for object list and count */ struct vm_object kernel_object_store; struct vm_object kmem_object_store; static SYSCTL_NODE(_vm_stats, OID_AUTO, object, CTLFLAG_RD, 0, "VM object stats"); static long object_collapses; SYSCTL_LONG(_vm_stats_object, OID_AUTO, collapses, CTLFLAG_RD, &object_collapses, 0, "VM object collapses"); static long object_bypasses; SYSCTL_LONG(_vm_stats_object, OID_AUTO, bypasses, CTLFLAG_RD, &object_bypasses, 0, "VM object bypasses"); static uma_zone_t obj_zone; static int vm_object_zinit(void *mem, int size, int flags); #ifdef INVARIANTS static void vm_object_zdtor(void *mem, int size, void *arg); static void vm_object_zdtor(void *mem, int size, void *arg) { vm_object_t object; object = (vm_object_t)mem; KASSERT(TAILQ_EMPTY(&object->memq), ("object %p has resident pages", object)); #if VM_NRESERVLEVEL > 0 KASSERT(LIST_EMPTY(&object->rvq), ("object %p has reservations", object)); #endif KASSERT(vm_object_cache_is_empty(object), ("object %p has cached pages", object)); KASSERT(object->paging_in_progress == 0, ("object %p paging_in_progress = %d", object, object->paging_in_progress)); KASSERT(object->resident_page_count == 0, ("object %p resident_page_count = %d", object, object->resident_page_count)); KASSERT(object->shadow_count == 0, ("object %p shadow_count = %d", object, object->shadow_count)); } #endif static int vm_object_zinit(void *mem, int size, int flags) { vm_object_t object; object = (vm_object_t)mem; bzero(&object->mtx, sizeof(object->mtx)); VM_OBJECT_LOCK_INIT(object, "standard object"); /* These are true for any object that has been freed */ object->paging_in_progress = 0; object->resident_page_count = 0; object->shadow_count = 0; return (0); } void _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) { TAILQ_INIT(&object->memq); LIST_INIT(&object->shadow_head); object->rtree.rt_root = 0; object->type = type; switch (type) { case OBJT_DEAD: panic("_vm_object_allocate: can't create OBJT_DEAD"); case OBJT_DEFAULT: case OBJT_SWAP: object->flags = OBJ_ONEMAPPING; break; case OBJT_DEVICE: case OBJT_SG: object->flags = OBJ_FICTITIOUS | OBJ_UNMANAGED; break; case OBJT_MGTDEVICE: object->flags = OBJ_FICTITIOUS; break; case OBJT_PHYS: object->flags = OBJ_UNMANAGED; break; case OBJT_VNODE: object->flags = 0; break; default: panic("_vm_object_allocate: type %d is undefined", type); } object->size = size; object->generation = 1; object->ref_count = 1; object->memattr = VM_MEMATTR_DEFAULT; object->cred = NULL; object->charge = 0; object->pg_color = 0; object->handle = NULL; object->backing_object = NULL; object->backing_object_offset = (vm_ooffset_t) 0; #if VM_NRESERVLEVEL > 0 LIST_INIT(&object->rvq); #endif object->cache.rt_root = 0; mtx_lock(&vm_object_list_mtx); TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); mtx_unlock(&vm_object_list_mtx); } /* * vm_object_init: * * Initialize the VM objects module. */ void vm_object_init(void) { TAILQ_INIT(&vm_object_list); mtx_init(&vm_object_list_mtx, "vm object_list", NULL, MTX_DEF); VM_OBJECT_LOCK_INIT(kernel_object, "kernel object"); _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), kernel_object); #if VM_NRESERVLEVEL > 0 kernel_object->flags |= OBJ_COLORED; kernel_object->pg_color = (u_short)atop(VM_MIN_KERNEL_ADDRESS); #endif VM_OBJECT_LOCK_INIT(kmem_object, "kmem object"); _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), kmem_object); #if VM_NRESERVLEVEL > 0 kmem_object->flags |= OBJ_COLORED; kmem_object->pg_color = (u_short)atop(VM_MIN_KERNEL_ADDRESS); #endif /* * The lock portion of struct vm_object must be type stable due * to vm_pageout_fallback_object_lock locking a vm object * without holding any references to it. */ obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, #ifdef INVARIANTS vm_object_zdtor, #else NULL, #endif vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); } void vm_object_clear_flag(vm_object_t object, u_short bits) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); object->flags &= ~bits; } /* * Sets the default memory attribute for the specified object. Pages * that are allocated to this object are by default assigned this memory * attribute. * * Presently, this function must be called before any pages are allocated * to the object. In the future, this requirement may be relaxed for * "default" and "swap" objects. */ int vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); switch (object->type) { case OBJT_DEFAULT: case OBJT_DEVICE: case OBJT_MGTDEVICE: case OBJT_PHYS: case OBJT_SG: case OBJT_SWAP: case OBJT_VNODE: - if (object->resident_page_count == 0) + if (!TAILQ_EMPTY(&object->memq)) return (KERN_FAILURE); break; case OBJT_DEAD: return (KERN_INVALID_ARGUMENT); default: panic("vm_object_set_memattr: object %p is of undefined type", object); } object->memattr = memattr; return (KERN_SUCCESS); } void vm_object_pip_add(vm_object_t object, short i) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); object->paging_in_progress += i; } void vm_object_pip_subtract(vm_object_t object, short i) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); object->paging_in_progress -= i; } void vm_object_pip_wakeup(vm_object_t object) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); object->paging_in_progress--; if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { vm_object_clear_flag(object, OBJ_PIPWNT); wakeup(object); } } void vm_object_pip_wakeupn(vm_object_t object, short i) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); if (i) object->paging_in_progress -= i; if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { vm_object_clear_flag(object, OBJ_PIPWNT); wakeup(object); } } void vm_object_pip_wait(vm_object_t object, char *waitid) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); while (object->paging_in_progress) { object->flags |= OBJ_PIPWNT; msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); } } /* * vm_object_allocate: * * Returns a new object with the given size. */ vm_object_t vm_object_allocate(objtype_t type, vm_pindex_t size) { vm_object_t object; object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); _vm_object_allocate(type, size, object); return (object); } /* * vm_object_reference: * * Gets another reference to the given object. Note: OBJ_DEAD * objects can be referenced during final cleaning. */ void vm_object_reference(vm_object_t object) { if (object == NULL) return; VM_OBJECT_LOCK(object); vm_object_reference_locked(object); VM_OBJECT_UNLOCK(object); } /* * vm_object_reference_locked: * * Gets another reference to the given object. * * The object must be locked. */ void vm_object_reference_locked(vm_object_t object) { struct vnode *vp; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); object->ref_count++; if (object->type == OBJT_VNODE) { vp = object->handle; vref(vp); } } /* * Handle deallocating an object of type OBJT_VNODE. */ static void vm_object_vndeallocate(vm_object_t object) { struct vnode *vp = (struct vnode *) object->handle; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT(object->type == OBJT_VNODE, ("vm_object_vndeallocate: not a vnode object")); KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); #ifdef INVARIANTS if (object->ref_count == 0) { vprint("vm_object_vndeallocate", vp); panic("vm_object_vndeallocate: bad object reference count"); } #endif if (object->ref_count > 1) { object->ref_count--; VM_OBJECT_UNLOCK(object); /* vrele may need the vnode lock. */ vrele(vp); } else { vhold(vp); VM_OBJECT_UNLOCK(object); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); vdrop(vp); VM_OBJECT_LOCK(object); object->ref_count--; if (object->type == OBJT_DEAD) { VM_OBJECT_UNLOCK(object); VOP_UNLOCK(vp, 0); } else { if (object->ref_count == 0) VOP_UNSET_TEXT(vp); VM_OBJECT_UNLOCK(object); vput(vp); } } } /* * vm_object_deallocate: * * Release a reference to the specified object, * gained either through a vm_object_allocate * or a vm_object_reference call. When all references * are gone, storage associated with this object * may be relinquished. * * No object may be locked. */ void vm_object_deallocate(vm_object_t object) { vm_object_t temp; while (object != NULL) { VM_OBJECT_LOCK(object); if (object->type == OBJT_VNODE) { vm_object_vndeallocate(object); return; } KASSERT(object->ref_count != 0, ("vm_object_deallocate: object deallocated too many times: %d", object->type)); /* * If the reference count goes to 0 we start calling * vm_object_terminate() on the object chain. * A ref count of 1 may be a special case depending on the * shadow count being 0 or 1. */ object->ref_count--; if (object->ref_count > 1) { VM_OBJECT_UNLOCK(object); return; } else if (object->ref_count == 1) { if (object->shadow_count == 0 && object->handle == NULL && (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { vm_object_set_flag(object, OBJ_ONEMAPPING); } else if ((object->shadow_count == 1) && (object->handle == NULL) && (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { vm_object_t robject; robject = LIST_FIRST(&object->shadow_head); KASSERT(robject != NULL, ("vm_object_deallocate: ref_count: %d, shadow_count: %d", object->ref_count, object->shadow_count)); if (!VM_OBJECT_TRYLOCK(robject)) { /* * Avoid a potential deadlock. */ object->ref_count++; VM_OBJECT_UNLOCK(object); /* * More likely than not the thread * holding robject's lock has lower * priority than the current thread. * Let the lower priority thread run. */ pause("vmo_de", 1); continue; } /* * Collapse object into its shadow unless its * shadow is dead. In that case, object will * be deallocated by the thread that is * deallocating its shadow. */ if ((robject->flags & OBJ_DEAD) == 0 && (robject->handle == NULL) && (robject->type == OBJT_DEFAULT || robject->type == OBJT_SWAP)) { robject->ref_count++; retry: if (robject->paging_in_progress) { VM_OBJECT_UNLOCK(object); vm_object_pip_wait(robject, "objde1"); temp = robject->backing_object; if (object == temp) { VM_OBJECT_LOCK(object); goto retry; } } else if (object->paging_in_progress) { VM_OBJECT_UNLOCK(robject); object->flags |= OBJ_PIPWNT; msleep(object, VM_OBJECT_MTX(object), PDROP | PVM, "objde2", 0); VM_OBJECT_LOCK(robject); temp = robject->backing_object; if (object == temp) { VM_OBJECT_LOCK(object); goto retry; } } else VM_OBJECT_UNLOCK(object); if (robject->ref_count == 1) { robject->ref_count--; object = robject; goto doterm; } object = robject; vm_object_collapse(object); VM_OBJECT_UNLOCK(object); continue; } VM_OBJECT_UNLOCK(robject); } VM_OBJECT_UNLOCK(object); return; } doterm: temp = object->backing_object; if (temp != NULL) { VM_OBJECT_LOCK(temp); LIST_REMOVE(object, shadow_list); temp->shadow_count--; VM_OBJECT_UNLOCK(temp); object->backing_object = NULL; } /* * Don't double-terminate, we could be in a termination * recursion due to the terminate having to sync data * to disk. */ if ((object->flags & OBJ_DEAD) == 0) vm_object_terminate(object); else VM_OBJECT_UNLOCK(object); object = temp; } } /* * vm_object_destroy removes the object from the global object list * and frees the space for the object. */ void vm_object_destroy(vm_object_t object) { /* * Remove the object from the global object list. */ mtx_lock(&vm_object_list_mtx); TAILQ_REMOVE(&vm_object_list, object, object_list); mtx_unlock(&vm_object_list_mtx); /* * Release the allocation charge. */ if (object->cred != NULL) { KASSERT(object->type == OBJT_DEFAULT || object->type == OBJT_SWAP, ("vm_object_terminate: non-swap obj %p has cred", object)); swap_release_by_cred(object->charge, object->cred); object->charge = 0; crfree(object->cred); object->cred = NULL; } /* * Free the space for the object. */ uma_zfree(obj_zone, object); } /* * vm_object_terminate actually destroys the specified object, freeing * up all previously used resources. * * The object must be locked. * This routine may block. */ void vm_object_terminate(vm_object_t object) { vm_page_t p, p_next; vm_pindex_t start; struct vnode *vp; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); /* * Make sure no one uses us. */ vm_object_set_flag(object, OBJ_DEAD); /* * wait for the pageout daemon to be done with the object */ vm_object_pip_wait(object, "objtrm"); KASSERT(!object->paging_in_progress, ("vm_object_terminate: pageout in progress")); /* * Clean and free the pages, as appropriate. All references to the * object are gone, so we don't need to lock it. */ if (object->type == OBJT_VNODE) { struct vnode *vp = (struct vnode *)object->handle; /* * Clean pages and flush buffers. */ vm_object_page_clean(object, 0, 0, OBJPC_SYNC); VM_OBJECT_UNLOCK(object); vinvalbuf(vp, V_SAVE, 0, 0); VM_OBJECT_LOCK(object); } KASSERT(object->ref_count == 0, ("vm_object_terminate: object with references, ref_count=%d", object->ref_count)); /* * Free any remaining pageable pages. This also removes them from the * paging queues. However, don't free wired pages, just remove them * from the object. Rather than incrementally removing each page from * the object, the page and object are reset to any empty state. */ TAILQ_FOREACH_SAFE(p, &object->memq, listq, p_next) { KASSERT(!p->busy && (p->oflags & VPO_BUSY) == 0, ("vm_object_terminate: freeing busy page %p", p)); vm_page_lock(p); /* * Optimize the page's removal from the object by resetting * its "object" field. Specifically, if the page is not * wired, then the effect of this assignment is that * vm_page_free()'s call to vm_page_remove() will return * immediately without modifying the page or the object. - */ + */ p->object = NULL; if (p->wire_count == 0) { vm_page_free(p); PCPU_INC(cnt.v_pfree); } vm_page_unlock(p); } vm_radix_reclaim_allnodes(&object->rtree); vp = NULL; if (!vm_object_cache_is_empty(object)) { start = 0; mtx_lock(&vm_page_queue_free_mtx); while ((p = vm_radix_lookup_ge(&object->cache, start)) != NULL) { MPASS(p->object == object); p->object = NULL; p->valid = 0; /* Clear PG_CACHED and set PG_FREE. */ p->flags ^= PG_CACHED | PG_FREE; cnt.v_cache_count--; cnt.v_free_count++; /* * At least one cached page was removed and * in the end all the cached pages will be * reclaimed. If the object is a vnode, * drop a reference to it. */ if (object->type == OBJT_VNODE) vp = object->handle; /* Point to the next available index. */ start = p->pindex + 1; if (start < p->pindex) break; } vm_radix_reclaim_allnodes(&object->cache); mtx_unlock(&vm_page_queue_free_mtx); } /* * If the object contained any pages, then reset it to an empty state. * None of the object's fields, including "resident_page_count", were * modified by the preceding loop. */ if (object->resident_page_count != 0) { TAILQ_INIT(&object->memq); object->resident_page_count = 0; if (object->type == OBJT_VNODE) vdrop(object->handle); } if (vp) vdrop(vp); #if VM_NRESERVLEVEL > 0 if (__predict_false(!LIST_EMPTY(&object->rvq))) vm_reserv_break_all(object); #endif /* * Let the pager know object is dead. */ vm_pager_deallocate(object); VM_OBJECT_UNLOCK(object); vm_object_destroy(object); } /* * Make the page read-only so that we can clear the object flags. However, if * this is a nosync mmap then the object is likely to stay dirty so do not * mess with the page and do not clear the object flags. Returns TRUE if the * page should be flushed, and FALSE otherwise. */ static boolean_t vm_object_page_remove_write(vm_page_t p, int flags, boolean_t *clearobjflags) { /* * If we have been asked to skip nosync pages and this is a * nosync page, skip it. Note that the object flags were not * cleared in this case so we do not have to set them. */ if ((flags & OBJPC_NOSYNC) != 0 && (p->oflags & VPO_NOSYNC) != 0) { *clearobjflags = FALSE; return (FALSE); } else { pmap_remove_write(p); return (p->dirty != 0); } } /* * vm_object_page_clean * * Clean all dirty pages in the specified range of object. Leaves page * on whatever queue it is currently on. If NOSYNC is set then do not * write out pages with VPO_NOSYNC set (originally comes from MAP_NOSYNC), * leaving the object dirty. * * When stuffing pages asynchronously, allow clustering. XXX we need a * synchronous clustering mode implementation. * * Odd semantics: if start == end, we clean everything. * * The object must be locked. * * Returns FALSE if some page from the range was not written, as * reported by the pager, and TRUE otherwise. */ boolean_t vm_object_page_clean(vm_object_t object, vm_ooffset_t start, vm_ooffset_t end, int flags) { vm_page_t np, p; vm_pindex_t pi, tend, tstart; int curgeneration, n, pagerflags; boolean_t clearobjflags, eio, res; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT(object->type == OBJT_VNODE, ("Not a vnode object")); if ((object->flags & OBJ_MIGHTBEDIRTY) == 0 || object->resident_page_count == 0) return (TRUE); pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) != 0 ? VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; pagerflags |= (flags & OBJPC_INVAL) != 0 ? VM_PAGER_PUT_INVAL : 0; tstart = OFF_TO_IDX(start); tend = (end == 0) ? object->size : OFF_TO_IDX(end + PAGE_MASK); clearobjflags = tstart == 0 && tend >= object->size; res = TRUE; rescan: curgeneration = object->generation; for (p = vm_page_find_least(object, tstart); p != NULL; p = np) { pi = p->pindex; if (pi >= tend) break; np = TAILQ_NEXT(p, listq); if (p->valid == 0) continue; if (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { if (object->generation != curgeneration) { if ((flags & OBJPC_SYNC) != 0) goto rescan; else clearobjflags = FALSE; } np = vm_page_find_least(object, pi); continue; } if (!vm_object_page_remove_write(p, flags, &clearobjflags)) continue; n = vm_object_page_collect_flush(object, p, pagerflags, flags, &clearobjflags, &eio); if (eio) { res = FALSE; clearobjflags = FALSE; } if (object->generation != curgeneration) { if ((flags & OBJPC_SYNC) != 0) goto rescan; else clearobjflags = FALSE; } /* * If the VOP_PUTPAGES() did a truncated write, so * that even the first page of the run is not fully * written, vm_pageout_flush() returns 0 as the run * length. Since the condition that caused truncated * write may be permanent, e.g. exhausted free space, * accepting n == 0 would cause an infinite loop. * * Forwarding the iterator leaves the unwritten page * behind, but there is not much we can do there if * filesystem refuses to write it. */ if (n == 0) { n = 1; clearobjflags = FALSE; } np = vm_page_find_least(object, pi + n); } #if 0 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC) ? MNT_WAIT : 0); #endif if (clearobjflags) vm_object_clear_flag(object, OBJ_MIGHTBEDIRTY); return (res); } static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags, int flags, boolean_t *clearobjflags, boolean_t *eio) { vm_page_t ma[vm_pageout_page_count], p_first, tp; int count, i, mreq, runlen; vm_page_lock_assert(p, MA_NOTOWNED); VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); count = 1; mreq = 0; for (tp = p; count < vm_pageout_page_count; count++) { tp = vm_page_next(tp); if (tp == NULL || tp->busy != 0 || (tp->oflags & VPO_BUSY) != 0) break; if (!vm_object_page_remove_write(tp, flags, clearobjflags)) break; } for (p_first = p; count < vm_pageout_page_count; count++) { tp = vm_page_prev(p_first); if (tp == NULL || tp->busy != 0 || (tp->oflags & VPO_BUSY) != 0) break; if (!vm_object_page_remove_write(tp, flags, clearobjflags)) break; p_first = tp; mreq++; } for (tp = p_first, i = 0; i < count; tp = TAILQ_NEXT(tp, listq), i++) ma[i] = tp; vm_pageout_flush(ma, count, pagerflags, mreq, &runlen, eio); return (runlen); } /* * Note that there is absolutely no sense in writing out * anonymous objects, so we track down the vnode object * to write out. * We invalidate (remove) all pages from the address space * for semantic correctness. * * If the backing object is a device object with unmanaged pages, then any * mappings to the specified range of pages must be removed before this * function is called. * * Note: certain anonymous maps, such as MAP_NOSYNC maps, * may start out with a NULL object. */ boolean_t vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, boolean_t syncio, boolean_t invalidate) { vm_object_t backing_object; struct vnode *vp; struct mount *mp; int error, flags, fsync_after; boolean_t res; if (object == NULL) return (TRUE); res = TRUE; error = 0; VM_OBJECT_LOCK(object); while ((backing_object = object->backing_object) != NULL) { VM_OBJECT_LOCK(backing_object); offset += object->backing_object_offset; VM_OBJECT_UNLOCK(object); object = backing_object; if (object->size < OFF_TO_IDX(offset + size)) size = IDX_TO_OFF(object->size) - offset; } /* * Flush pages if writing is allowed, invalidate them * if invalidation requested. Pages undergoing I/O * will be ignored by vm_object_page_remove(). * * We cannot lock the vnode and then wait for paging * to complete without deadlocking against vm_fault. * Instead we simply call vm_object_page_remove() and * allow it to block internally on a page-by-page * basis when it encounters pages undergoing async * I/O. */ if (object->type == OBJT_VNODE && (object->flags & OBJ_MIGHTBEDIRTY) != 0) { vp = object->handle; VM_OBJECT_UNLOCK(object); (void) vn_start_write(vp, &mp, V_WAIT); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); if (syncio && !invalidate && offset == 0 && OFF_TO_IDX(size) == object->size) { /* * If syncing the whole mapping of the file, * it is faster to schedule all the writes in * async mode, also allowing the clustering, * and then wait for i/o to complete. */ flags = 0; fsync_after = TRUE; } else { flags = (syncio || invalidate) ? OBJPC_SYNC : 0; flags |= invalidate ? (OBJPC_SYNC | OBJPC_INVAL) : 0; fsync_after = FALSE; } VM_OBJECT_LOCK(object); res = vm_object_page_clean(object, offset, offset + size, flags); VM_OBJECT_UNLOCK(object); if (fsync_after) error = VOP_FSYNC(vp, MNT_WAIT, curthread); VOP_UNLOCK(vp, 0); vn_finished_write(mp); if (error != 0) res = FALSE; VM_OBJECT_LOCK(object); } if ((object->type == OBJT_VNODE || object->type == OBJT_DEVICE) && invalidate) { if (object->type == OBJT_DEVICE) /* * The option OBJPR_NOTMAPPED must be passed here * because vm_object_page_remove() cannot remove * unmanaged mappings. */ flags = OBJPR_NOTMAPPED; else if (old_msync) flags = 0; else flags = OBJPR_CLEANONLY; vm_object_page_remove(object, OFF_TO_IDX(offset), OFF_TO_IDX(offset + size + PAGE_MASK), flags); } VM_OBJECT_UNLOCK(object); return (res); } /* * vm_object_madvise: * * Implements the madvise function at the object/page level. * * MADV_WILLNEED (any object) * * Activate the specified pages if they are resident. * * MADV_DONTNEED (any object) * * Deactivate the specified pages if they are resident. * * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, * OBJ_ONEMAPPING only) * * Deactivate and clean the specified pages if they are * resident. This permits the process to reuse the pages * without faulting or the kernel to reclaim the pages * without I/O. */ void vm_object_madvise(vm_object_t object, vm_pindex_t pindex, vm_pindex_t end, int advise) { vm_pindex_t tpindex; vm_object_t backing_object, tobject; vm_page_t m; if (object == NULL) return; VM_OBJECT_LOCK(object); /* * Locate and adjust resident pages */ for (; pindex < end; pindex += 1) { relookup: tobject = object; tpindex = pindex; shadowlookup: /* * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages * and those pages must be OBJ_ONEMAPPING. */ if (advise == MADV_FREE) { if ((tobject->type != OBJT_DEFAULT && tobject->type != OBJT_SWAP) || (tobject->flags & OBJ_ONEMAPPING) == 0) { goto unlock_tobject; } } else if ((tobject->flags & OBJ_UNMANAGED) != 0) goto unlock_tobject; m = vm_page_lookup(tobject, tpindex); if (m == NULL && advise == MADV_WILLNEED) { /* * If the page is cached, reactivate it. */ m = vm_page_alloc(tobject, tpindex, VM_ALLOC_IFCACHED | VM_ALLOC_NOBUSY); } if (m == NULL) { /* * There may be swap even if there is no backing page */ if (advise == MADV_FREE && tobject->type == OBJT_SWAP) swap_pager_freespace(tobject, tpindex, 1); /* * next object */ backing_object = tobject->backing_object; if (backing_object == NULL) goto unlock_tobject; VM_OBJECT_LOCK(backing_object); tpindex += OFF_TO_IDX(tobject->backing_object_offset); if (tobject != object) VM_OBJECT_UNLOCK(tobject); tobject = backing_object; goto shadowlookup; } else if (m->valid != VM_PAGE_BITS_ALL) goto unlock_tobject; /* * If the page is not in a normal state, skip it. */ vm_page_lock(m); if (m->hold_count != 0 || m->wire_count != 0) { vm_page_unlock(m); goto unlock_tobject; } KASSERT((m->flags & PG_FICTITIOUS) == 0, ("vm_object_madvise: page %p is fictitious", m)); KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("vm_object_madvise: page %p is not managed", m)); if ((m->oflags & VPO_BUSY) || m->busy) { if (advise == MADV_WILLNEED) { /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ vm_page_aflag_set(m, PGA_REFERENCED); } vm_page_unlock(m); if (object != tobject) VM_OBJECT_UNLOCK(object); m->oflags |= VPO_WANTED; msleep(m, VM_OBJECT_MTX(tobject), PDROP | PVM, "madvpo", 0); VM_OBJECT_LOCK(object); goto relookup; } if (advise == MADV_WILLNEED) { vm_page_activate(m); } else if (advise == MADV_DONTNEED) { vm_page_dontneed(m); } else if (advise == MADV_FREE) { /* * Mark the page clean. This will allow the page * to be freed up by the system. However, such pages * are often reused quickly by malloc()/free() * so we do not do anything that would cause * a page fault if we can help it. * * Specifically, we do not try to actually free * the page now nor do we try to put it in the * cache (which would cause a page fault on reuse). * * But we do make the page is freeable as we * can without actually taking the step of unmapping * it. */ pmap_clear_modify(m); m->dirty = 0; m->act_count = 0; vm_page_dontneed(m); } vm_page_unlock(m); if (advise == MADV_FREE && tobject->type == OBJT_SWAP) swap_pager_freespace(tobject, tpindex, 1); unlock_tobject: if (tobject != object) VM_OBJECT_UNLOCK(tobject); } VM_OBJECT_UNLOCK(object); } /* * vm_object_shadow: * * Create a new object which is backed by the * specified existing object range. The source * object reference is deallocated. * * The new object and offset into that object * are returned in the source parameters. */ void vm_object_shadow( vm_object_t *object, /* IN/OUT */ vm_ooffset_t *offset, /* IN/OUT */ vm_size_t length) { vm_object_t source; vm_object_t result; source = *object; /* * Don't create the new object if the old object isn't shared. */ if (source != NULL) { VM_OBJECT_LOCK(source); if (source->ref_count == 1 && source->handle == NULL && (source->type == OBJT_DEFAULT || source->type == OBJT_SWAP)) { VM_OBJECT_UNLOCK(source); return; } VM_OBJECT_UNLOCK(source); } /* * Allocate a new object with the given length. */ result = vm_object_allocate(OBJT_DEFAULT, atop(length)); /* * The new object shadows the source object, adding a reference to it. * Our caller changes his reference to point to the new object, * removing a reference to the source object. Net result: no change * of reference count. * * Try to optimize the result object's page color when shadowing * in order to maintain page coloring consistency in the combined * shadowed object. */ result->backing_object = source; /* * Store the offset into the source object, and fix up the offset into * the new object. */ result->backing_object_offset = *offset; if (source != NULL) { VM_OBJECT_LOCK(source); LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); source->shadow_count++; #if VM_NRESERVLEVEL > 0 result->flags |= source->flags & OBJ_COLORED; result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & ((1 << (VM_NFREEORDER - 1)) - 1); #endif VM_OBJECT_UNLOCK(source); } /* * Return the new things */ *offset = 0; *object = result; } /* * vm_object_split: * * Split the pages in a map entry into a new object. This affords * easier removal of unused pages, and keeps object inheritance from * being a negative impact on memory usage. */ void vm_object_split(vm_map_entry_t entry) { vm_page_t m, m_next; vm_object_t orig_object, new_object, source; vm_pindex_t idx, offidxstart, start; vm_size_t size; orig_object = entry->object.vm_object; if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) return; if (orig_object->ref_count <= 1) return; VM_OBJECT_UNLOCK(orig_object); offidxstart = OFF_TO_IDX(entry->offset); size = atop(entry->end - entry->start); /* * If swap_pager_copy() is later called, it will convert new_object * into a swap object. */ new_object = vm_object_allocate(OBJT_DEFAULT, size); /* * At this point, the new object is still private, so the order in * which the original and new objects are locked does not matter. */ VM_OBJECT_LOCK(new_object); VM_OBJECT_LOCK(orig_object); source = orig_object->backing_object; if (source != NULL) { VM_OBJECT_LOCK(source); if ((source->flags & OBJ_DEAD) != 0) { VM_OBJECT_UNLOCK(source); VM_OBJECT_UNLOCK(orig_object); VM_OBJECT_UNLOCK(new_object); vm_object_deallocate(new_object); VM_OBJECT_LOCK(orig_object); return; } LIST_INSERT_HEAD(&source->shadow_head, new_object, shadow_list); source->shadow_count++; vm_object_reference_locked(source); /* for new_object */ vm_object_clear_flag(source, OBJ_ONEMAPPING); VM_OBJECT_UNLOCK(source); new_object->backing_object_offset = orig_object->backing_object_offset + entry->offset; new_object->backing_object = source; } if (orig_object->cred != NULL) { new_object->cred = orig_object->cred; crhold(orig_object->cred); new_object->charge = ptoa(size); KASSERT(orig_object->charge >= ptoa(size), ("orig_object->charge < 0")); orig_object->charge -= ptoa(size); } retry: m = vm_page_find_least(orig_object, offidxstart); for (; m != NULL && (idx = m->pindex - offidxstart) < size; m = m_next) { m_next = TAILQ_NEXT(m, listq); /* * We must wait for pending I/O to complete before we can * rename the page. * * We do not have to VM_PROT_NONE the page as mappings should * not be changed by this operation. */ if ((m->oflags & VPO_BUSY) || m->busy) { VM_OBJECT_UNLOCK(new_object); m->oflags |= VPO_WANTED; msleep(m, VM_OBJECT_MTX(orig_object), PVM, "spltwt", 0); VM_OBJECT_LOCK(new_object); goto retry; } #if VM_NRESERVLEVEL > 0 /* * If some of the reservation's allocated pages remain with * the original object, then transferring the reservation to * the new object is neither particularly beneficial nor * particularly harmful as compared to leaving the reservation * with the original object. If, however, all of the * reservation's allocated pages are transferred to the new * object, then transferring the reservation is typically * beneficial. Determining which of these two cases applies * would be more costly than unconditionally renaming the * reservation. */ vm_reserv_rename(m, new_object, orig_object, offidxstart); #endif vm_page_lock(m); vm_page_rename(m, new_object, idx); vm_page_unlock(m); /* page automatically made dirty by rename and cache handled */ vm_page_busy(m); } if (orig_object->type == OBJT_SWAP) { /* * swap_pager_copy() can sleep, in which case the orig_object's * and new_object's locks are released and reacquired. */ swap_pager_copy(orig_object, new_object, offidxstart, 0); /* * Transfer any cached pages from orig_object to new_object. * If swap_pager_copy() found swapped out pages within the * specified range of orig_object, then it changed * new_object's type to OBJT_SWAP when it transferred those * pages to new_object. Otherwise, new_object's type * should still be OBJT_DEFAULT and orig_object should not * contain any cached pages within the specified range. */ if (!vm_object_cache_is_empty(orig_object)) { start = offidxstart; mtx_lock(&vm_page_queue_free_mtx); while ((m = vm_radix_lookup_ge(&orig_object->cache, start)) != NULL) { if (m->pindex >= (offidxstart + size)) break; idx = m->pindex - offidxstart; vm_page_cache_rename(m, new_object, idx); } mtx_unlock(&vm_page_queue_free_mtx); } } VM_OBJECT_UNLOCK(orig_object); TAILQ_FOREACH(m, &new_object->memq, listq) vm_page_wakeup(m); VM_OBJECT_UNLOCK(new_object); entry->object.vm_object = new_object; entry->offset = 0LL; vm_object_deallocate(orig_object); VM_OBJECT_LOCK(new_object); } #define OBSC_TEST_ALL_SHADOWED 0x0001 #define OBSC_COLLAPSE_NOWAIT 0x0002 #define OBSC_COLLAPSE_WAIT 0x0004 static int vm_object_backing_scan(vm_object_t object, int op) { int r = 1; vm_page_t p; vm_object_t backing_object; vm_pindex_t backing_offset_index; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); backing_object = object->backing_object; backing_offset_index = OFF_TO_IDX(object->backing_object_offset); /* * Initial conditions */ if (op & OBSC_TEST_ALL_SHADOWED) { /* * We do not want to have to test for the existence of cache * or swap pages in the backing object. XXX but with the * new swapper this would be pretty easy to do. * * XXX what about anonymous MAP_SHARED memory that hasn't * been ZFOD faulted yet? If we do not test for this, the * shadow test may succeed! XXX */ if (backing_object->type != OBJT_DEFAULT) { return (0); } } if (op & OBSC_COLLAPSE_WAIT) { vm_object_set_flag(backing_object, OBJ_DEAD); } /* * Our scan */ p = TAILQ_FIRST(&backing_object->memq); while (p) { vm_page_t next = TAILQ_NEXT(p, listq); vm_pindex_t new_pindex = p->pindex - backing_offset_index; if (op & OBSC_TEST_ALL_SHADOWED) { vm_page_t pp; /* * Ignore pages outside the parent object's range * and outside the parent object's mapping of the * backing object. * * note that we do not busy the backing object's * page. */ if ( p->pindex < backing_offset_index || new_pindex >= object->size ) { p = next; continue; } /* * See if the parent has the page or if the parent's * object pager has the page. If the parent has the * page but the page is not valid, the parent's * object pager must have the page. * * If this fails, the parent does not completely shadow * the object and we might as well give up now. */ pp = vm_page_lookup(object, new_pindex); if ( (pp == NULL || pp->valid == 0) && !vm_pager_has_page(object, new_pindex, NULL, NULL) ) { r = 0; break; } } /* * Check for busy page */ if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { vm_page_t pp; if (op & OBSC_COLLAPSE_NOWAIT) { if ((p->oflags & VPO_BUSY) || !p->valid || p->busy) { p = next; continue; } } else if (op & OBSC_COLLAPSE_WAIT) { if ((p->oflags & VPO_BUSY) || p->busy) { VM_OBJECT_UNLOCK(object); p->oflags |= VPO_WANTED; msleep(p, VM_OBJECT_MTX(backing_object), PDROP | PVM, "vmocol", 0); VM_OBJECT_LOCK(object); VM_OBJECT_LOCK(backing_object); /* * If we slept, anything could have * happened. Since the object is * marked dead, the backing offset * should not have changed so we * just restart our scan. */ p = TAILQ_FIRST(&backing_object->memq); continue; } } KASSERT( p->object == backing_object, ("vm_object_backing_scan: object mismatch") ); /* * Destroy any associated swap */ if (backing_object->type == OBJT_SWAP) { swap_pager_freespace( backing_object, p->pindex, 1 ); } if ( p->pindex < backing_offset_index || new_pindex >= object->size ) { /* * Page is out of the parent object's range, we * can simply destroy it. */ vm_page_lock(p); KASSERT(!pmap_page_is_mapped(p), ("freeing mapped page %p", p)); if (p->wire_count == 0) vm_page_free(p); else vm_page_remove(p); vm_page_unlock(p); p = next; continue; } pp = vm_page_lookup(object, new_pindex); if ( (op & OBSC_COLLAPSE_NOWAIT) != 0 && (pp != NULL && pp->valid == 0) ) { /* * The page in the parent is not (yet) valid. * We don't know anything about the state of * the original page. It might be mapped, * so we must avoid the next if here. * * This is due to a race in vm_fault() where * we must unbusy the original (backing_obj) * page before we can (re)lock the parent. * Hence we can get here. */ p = next; continue; } if ( pp != NULL || vm_pager_has_page(object, new_pindex, NULL, NULL) ) { /* * page already exists in parent OR swap exists * for this location in the parent. Destroy * the original page from the backing object. * * Leave the parent's page alone */ vm_page_lock(p); KASSERT(!pmap_page_is_mapped(p), ("freeing mapped page %p", p)); if (p->wire_count == 0) vm_page_free(p); else vm_page_remove(p); vm_page_unlock(p); p = next; continue; } #if VM_NRESERVLEVEL > 0 /* * Rename the reservation. */ vm_reserv_rename(p, object, backing_object, backing_offset_index); #endif /* * Page does not exist in parent, rename the * page from the backing object to the main object. * * If the page was mapped to a process, it can remain * mapped through the rename. */ vm_page_lock(p); vm_page_rename(p, object, new_pindex); vm_page_unlock(p); /* page automatically made dirty by rename */ } p = next; } return (r); } /* * this version of collapse allows the operation to occur earlier and * when paging_in_progress is true for an object... This is not a complete * operation, but should plug 99.9% of the rest of the leaks. */ static void vm_object_qcollapse(vm_object_t object) { vm_object_t backing_object = object->backing_object; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); if (backing_object->ref_count != 1) return; vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); } /* * vm_object_collapse: * * Collapse an object with the object backing it. * Pages in the backing object are moved into the * parent, and the backing object is deallocated. */ void vm_object_collapse(vm_object_t object) { vm_page_t p; vm_pindex_t start, tmpindex; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); while (TRUE) { vm_object_t backing_object; /* * Verify that the conditions are right for collapse: * * The object exists and the backing object exists. */ if ((backing_object = object->backing_object) == NULL) break; /* * we check the backing object first, because it is most likely * not collapsable. */ VM_OBJECT_LOCK(backing_object); if (backing_object->handle != NULL || (backing_object->type != OBJT_DEFAULT && backing_object->type != OBJT_SWAP) || (backing_object->flags & OBJ_DEAD) || object->handle != NULL || (object->type != OBJT_DEFAULT && object->type != OBJT_SWAP) || (object->flags & OBJ_DEAD)) { VM_OBJECT_UNLOCK(backing_object); break; } if ( object->paging_in_progress != 0 || backing_object->paging_in_progress != 0 ) { vm_object_qcollapse(object); VM_OBJECT_UNLOCK(backing_object); break; } /* * We know that we can either collapse the backing object (if * the parent is the only reference to it) or (perhaps) have * the parent bypass the object if the parent happens to shadow * all the resident pages in the entire backing object. * * This is ignoring pager-backed pages such as swap pages. * vm_object_backing_scan fails the shadowing test in this * case. */ if (backing_object->ref_count == 1) { /* * If there is exactly one reference to the backing * object, we can collapse it into the parent. */ vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); #if VM_NRESERVLEVEL > 0 /* * Break any reservations from backing_object. */ if (__predict_false(!LIST_EMPTY(&backing_object->rvq))) vm_reserv_break_all(backing_object); #endif /* * Move the pager from backing_object to object. */ if (backing_object->type == OBJT_SWAP) { /* * swap_pager_copy() can sleep, in which case * the backing_object's and object's locks are * released and reacquired. * Since swap_pager_copy() is being asked to * destroy the source, it will change the * backing_object's type to OBJT_DEFAULT. */ swap_pager_copy( backing_object, object, OFF_TO_IDX(object->backing_object_offset), TRUE); if (!vm_object_cache_is_empty(backing_object)) { /* * Free any cached pages from * backing_object. */ start = 0; mtx_lock(&vm_page_queue_free_mtx); while ((p = vm_radix_lookup_ge(&backing_object->cache, start)) != NULL) { tmpindex = p->pindex; vm_page_cache_free(p); /* * Point to the next available * index. */ start = tmpindex + 1; if (start < tmpindex) break; } mtx_unlock(&vm_page_queue_free_mtx); } } - /* * Object now shadows whatever backing_object did. * Note that the reference to * backing_object->backing_object moves from within * backing_object to within object. */ LIST_REMOVE(object, shadow_list); backing_object->shadow_count--; if (backing_object->backing_object) { VM_OBJECT_LOCK(backing_object->backing_object); LIST_REMOVE(backing_object, shadow_list); LIST_INSERT_HEAD( &backing_object->backing_object->shadow_head, object, shadow_list); /* * The shadow_count has not changed. */ VM_OBJECT_UNLOCK(backing_object->backing_object); } object->backing_object = backing_object->backing_object; object->backing_object_offset += backing_object->backing_object_offset; /* * Discard backing_object. * * Since the backing object has no pages, no pager left, * and no object references within it, all that is * necessary is to dispose of it. */ KASSERT(backing_object->ref_count == 1, ( "backing_object %p was somehow re-referenced during collapse!", backing_object)); VM_OBJECT_UNLOCK(backing_object); vm_object_destroy(backing_object); object_collapses++; } else { vm_object_t new_backing_object; /* * If we do not entirely shadow the backing object, * there is nothing we can do so we give up. */ if (object->resident_page_count != object->size && vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) { VM_OBJECT_UNLOCK(backing_object); break; } /* * Make the parent shadow the next object in the * chain. Deallocating backing_object will not remove * it, since its reference count is at least 2. */ LIST_REMOVE(object, shadow_list); backing_object->shadow_count--; new_backing_object = backing_object->backing_object; if ((object->backing_object = new_backing_object) != NULL) { VM_OBJECT_LOCK(new_backing_object); LIST_INSERT_HEAD( &new_backing_object->shadow_head, object, shadow_list ); new_backing_object->shadow_count++; vm_object_reference_locked(new_backing_object); VM_OBJECT_UNLOCK(new_backing_object); object->backing_object_offset += backing_object->backing_object_offset; } /* * Drop the reference count on backing_object. Since * its ref_count was at least 2, it will not vanish. */ backing_object->ref_count--; VM_OBJECT_UNLOCK(backing_object); object_bypasses++; } /* * Try again with this object's new backing object. */ } } /* * vm_object_page_remove: * * For the given object, either frees or invalidates each of the * specified pages. In general, a page is freed. However, if a page is * wired for any reason other than the existence of a managed, wired * mapping, then it may be invalidated but not removed from the object. * Pages are specified by the given range ["start", "end") and the option * OBJPR_CLEANONLY. As a special case, if "end" is zero, then the range * extends from "start" to the end of the object. If the option * OBJPR_CLEANONLY is specified, then only the non-dirty pages within the * specified range are affected. If the option OBJPR_NOTMAPPED is * specified, then the pages within the specified range must have no * mappings. Otherwise, if this option is not specified, any mappings to * the specified pages are removed before the pages are freed or * invalidated. * * In general, this operation should only be performed on objects that * contain managed pages. There are, however, two exceptions. First, it * is performed on the kernel and kmem objects by vm_map_entry_delete(). * Second, it is used by msync(..., MS_INVALIDATE) to invalidate device- * backed pages. In both of these cases, the option OBJPR_CLEANONLY must * not be specified and the option OBJPR_NOTMAPPED must be specified. * * The object must be locked. */ void vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int options) { struct vnode *vp; vm_page_t p, next; int wirings; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT((object->flags & OBJ_UNMANAGED) == 0 || (options & (OBJPR_CLEANONLY | OBJPR_NOTMAPPED)) == OBJPR_NOTMAPPED, ("vm_object_page_remove: illegal options for object %p", object)); if (object->resident_page_count == 0) { if (vm_object_cache_is_empty(object)) return; goto skipmemq; } vm_object_pip_add(object, 1); again: p = vm_page_find_least(object, start); /* * Here, the variable "p" is either (1) the page with the least pindex - * greater than or equal to the parameter "start" or (2) NULL. + * greater than or equal to the parameter "start" or (2) NULL. */ for (; p != NULL && (p->pindex < end || end == 0); p = next) { next = TAILQ_NEXT(p, listq); /* * If the page is wired for any reason besides the existence * of managed, wired mappings, then it cannot be freed. For * example, fictitious pages, which represent device memory, * are inherently wired and cannot be freed. They can, * however, be invalidated if the option OBJPR_CLEANONLY is * not specified. */ vm_page_lock(p); if ((wirings = p->wire_count) != 0 && (wirings = pmap_page_wired_mappings(p)) != p->wire_count) { if ((options & OBJPR_NOTMAPPED) == 0) { pmap_remove_all(p); /* Account for removal of wired mappings. */ if (wirings != 0) { KASSERT(p->wire_count == wirings, ("inconsistent wire count %d %d %p", p->wire_count, wirings, p)); p->wire_count = 0; atomic_subtract_int(&cnt.v_wire_count, 1); } if (wirings != 0) p->wire_count -= wirings; } if ((options & OBJPR_CLEANONLY) == 0) { p->valid = 0; vm_page_undirty(p); } vm_page_unlock(p); continue; } if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) goto again; KASSERT((p->flags & PG_FICTITIOUS) == 0, ("vm_object_page_remove: page %p is fictitious", p)); if ((options & OBJPR_CLEANONLY) != 0 && p->valid != 0) { if ((options & OBJPR_NOTMAPPED) == 0) pmap_remove_write(p); if (p->dirty) { vm_page_unlock(p); continue; } } if ((options & OBJPR_NOTMAPPED) == 0) { pmap_remove_all(p); /* Account for removal of wired mappings. */ if (wirings != 0) { KASSERT(p->wire_count == wirings, ("inconsistent wire count %d %d %p", p->wire_count, wirings, p)); p->wire_count = 0; atomic_subtract_int(&cnt.v_wire_count, 1); } } vm_page_free(p); vm_page_unlock(p); } vm_object_pip_wakeup(object); skipmemq: vp = NULL; if (!vm_object_cache_is_empty(object)) { mtx_lock(&vm_page_queue_free_mtx); while ((p = vm_radix_lookup_ge(&object->cache, start)) != NULL) { if (p->pindex >= end) break; vm_page_cache_free(p); if (vm_object_cache_is_empty(object) && object->type == OBJT_VNODE) vp = object->handle; } mtx_unlock(&vm_page_queue_free_mtx); } if (vp) vdrop(vp); } /* * vm_object_page_cache: * * For the given object, attempt to move the specified clean * pages to the cache queue. If a page is wired for any reason, * then it will not be changed. Pages are specified by the given * range ["start", "end"). As a special case, if "end" is zero, * then the range extends from "start" to the end of the object. * Any mappings to the specified pages are removed before the * pages are moved to the cache queue. * * This operation should only be performed on objects that * contain non-fictitious, managed pages. * * The object must be locked. */ void vm_object_page_cache(vm_object_t object, vm_pindex_t start, vm_pindex_t end) { struct mtx *mtx, *new_mtx; vm_page_t p, next; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT((object->flags & (OBJ_FICTITIOUS | OBJ_UNMANAGED)) == 0, ("vm_object_page_cache: illegal object %p", object)); if (object->resident_page_count == 0) return; p = vm_page_find_least(object, start); /* * Here, the variable "p" is either (1) the page with the least pindex * greater than or equal to the parameter "start" or (2) NULL. */ mtx = NULL; for (; p != NULL && (p->pindex < end || end == 0); p = next) { next = TAILQ_NEXT(p, listq); /* * Avoid releasing and reacquiring the same page lock. */ new_mtx = vm_page_lockptr(p); if (mtx != new_mtx) { if (mtx != NULL) mtx_unlock(mtx); mtx = new_mtx; mtx_lock(mtx); } vm_page_try_to_cache(p); } if (mtx != NULL) mtx_unlock(mtx); } /* * Populate the specified range of the object with valid pages. Returns * TRUE if the range is successfully populated and FALSE otherwise. * * Note: This function should be optimized to pass a larger array of * pages to vm_pager_get_pages() before it is applied to a non- * OBJT_DEVICE object. * * The object must be locked. */ boolean_t vm_object_populate(vm_object_t object, vm_pindex_t start, vm_pindex_t end) { vm_page_t m, ma[1]; vm_pindex_t pindex; int rv; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); for (pindex = start; pindex < end; pindex++) { m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (m->valid != VM_PAGE_BITS_ALL) { ma[0] = m; rv = vm_pager_get_pages(object, ma, 1, 0); m = vm_page_lookup(object, pindex); if (m == NULL) break; if (rv != VM_PAGER_OK) { vm_page_lock(m); vm_page_free(m); vm_page_unlock(m); break; } } /* * Keep "m" busy because a subsequent iteration may unlock * the object. */ } if (pindex > start) { m = vm_page_lookup(object, start); while (m != NULL && m->pindex < pindex) { vm_page_wakeup(m); m = TAILQ_NEXT(m, listq); } } return (pindex == end); } /* * Routine: vm_object_coalesce * Function: Coalesces two objects backing up adjoining * regions of memory into a single object. * * returns TRUE if objects were combined. * * NOTE: Only works at the moment if the second object is NULL - * if it's not, which object do we lock first? * * Parameters: * prev_object First object to coalesce * prev_offset Offset into prev_object * prev_size Size of reference to prev_object * next_size Size of reference to the second object * reserved Indicator that extension region has * swap accounted for * * Conditions: * The object must *not* be locked. */ boolean_t vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, vm_size_t prev_size, vm_size_t next_size, boolean_t reserved) { vm_pindex_t next_pindex; if (prev_object == NULL) return (TRUE); VM_OBJECT_LOCK(prev_object); if (prev_object->type != OBJT_DEFAULT && prev_object->type != OBJT_SWAP) { VM_OBJECT_UNLOCK(prev_object); return (FALSE); } /* * Try to collapse the object first */ vm_object_collapse(prev_object); /* * Can't coalesce if: . more than one reference . paged out . shadows * another object . has a copy elsewhere (any of which mean that the * pages not mapped to prev_entry may be in use anyway) */ if (prev_object->backing_object != NULL) { VM_OBJECT_UNLOCK(prev_object); return (FALSE); } prev_size >>= PAGE_SHIFT; next_size >>= PAGE_SHIFT; next_pindex = OFF_TO_IDX(prev_offset) + prev_size; if ((prev_object->ref_count > 1) && (prev_object->size != next_pindex)) { VM_OBJECT_UNLOCK(prev_object); return (FALSE); } /* * Account for the charge. */ if (prev_object->cred != NULL) { /* * If prev_object was charged, then this mapping, * althought not charged now, may become writable * later. Non-NULL cred in the object would prevent * swap reservation during enabling of the write * access, so reserve swap now. Failed reservation * cause allocation of the separate object for the map * entry, and swap reservation for this entry is * managed in appropriate time. */ if (!reserved && !swap_reserve_by_cred(ptoa(next_size), prev_object->cred)) { return (FALSE); } prev_object->charge += ptoa(next_size); } /* * Remove any pages that may still be in the object from a previous * deallocation. */ if (next_pindex < prev_object->size) { vm_object_page_remove(prev_object, next_pindex, next_pindex + next_size, 0); if (prev_object->type == OBJT_SWAP) swap_pager_freespace(prev_object, next_pindex, next_size); #if 0 if (prev_object->cred != NULL) { KASSERT(prev_object->charge >= ptoa(prev_object->size - next_pindex), ("object %p overcharged 1 %jx %jx", prev_object, (uintmax_t)next_pindex, (uintmax_t)next_size)); prev_object->charge -= ptoa(prev_object->size - next_pindex); } #endif } /* * Extend the object if necessary. */ if (next_pindex + next_size > prev_object->size) prev_object->size = next_pindex + next_size; VM_OBJECT_UNLOCK(prev_object); return (TRUE); } void vm_object_set_writeable_dirty(vm_object_t object) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); if (object->type != OBJT_VNODE) return; object->generation++; if ((object->flags & OBJ_MIGHTBEDIRTY) != 0) return; vm_object_set_flag(object, OBJ_MIGHTBEDIRTY); } int vm_object_cache_is_empty(vm_object_t object) { return (__predict_true(object->cache.rt_root == 0)); } #include "opt_ddb.h" #ifdef DDB #include #include #include static int _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) { vm_map_t tmpm; vm_map_entry_t tmpe; vm_object_t obj; int entcount; if (map == 0) return 0; if (entry == 0) { tmpe = map->header.next; entcount = map->nentries; while (entcount-- && (tmpe != &map->header)) { if (_vm_object_in_map(map, object, tmpe)) { return 1; } tmpe = tmpe->next; } } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { tmpm = entry->object.sub_map; tmpe = tmpm->header.next; entcount = tmpm->nentries; while (entcount-- && tmpe != &tmpm->header) { if (_vm_object_in_map(tmpm, object, tmpe)) { return 1; } tmpe = tmpe->next; } } else if ((obj = entry->object.vm_object) != NULL) { for (; obj; obj = obj->backing_object) if (obj == object) { return 1; } } return 0; } static int vm_object_in_map(vm_object_t object) { struct proc *p; /* sx_slock(&allproc_lock); */ FOREACH_PROC_IN_SYSTEM(p) { if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) continue; if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { /* sx_sunlock(&allproc_lock); */ return 1; } } /* sx_sunlock(&allproc_lock); */ if (_vm_object_in_map(kernel_map, object, 0)) return 1; if (_vm_object_in_map(kmem_map, object, 0)) return 1; if (_vm_object_in_map(pager_map, object, 0)) return 1; if (_vm_object_in_map(buffer_map, object, 0)) return 1; return 0; } DB_SHOW_COMMAND(vmochk, vm_object_check) { vm_object_t object; /* * make sure that internal objs are in a map somewhere * and none have zero ref counts. */ TAILQ_FOREACH(object, &vm_object_list, object_list) { if (object->handle == NULL && (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { if (object->ref_count == 0) { db_printf("vmochk: internal obj has zero ref count: %ld\n", (long)object->size); } if (!vm_object_in_map(object)) { db_printf( "vmochk: internal obj is not in a map: " "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", object->ref_count, (u_long)object->size, (u_long)object->size, (void *)object->backing_object); } } } } /* * vm_object_print: [ debug ] */ DB_SHOW_COMMAND(object, vm_object_print_static) { /* XXX convert args. */ vm_object_t object = (vm_object_t)addr; boolean_t full = have_addr; vm_page_t p; /* XXX count is an (unused) arg. Avoid shadowing it. */ #define count was_count int count; if (object == NULL) return; db_iprintf( "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x ruid %d charge %jx\n", object, (int)object->type, (uintmax_t)object->size, object->resident_page_count, object->ref_count, object->flags, object->cred ? object->cred->cr_ruid : -1, (uintmax_t)object->charge); db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", object->shadow_count, object->backing_object ? object->backing_object->ref_count : 0, object->backing_object, (uintmax_t)object->backing_object_offset); if (!full) return; db_indent += 2; count = 0; TAILQ_FOREACH(p, &object->memq, listq) { if (count == 0) db_iprintf("memory:="); else if (count == 6) { db_printf("\n"); db_iprintf(" ..."); count = 0; } else db_printf(","); count++; - db_printf("(off=0x%jx,page=0x%jx,obj=%p,flags=0x%X)", - (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p), - p->object, p->flags); + db_printf("(off=0x%jx,page=0x%jx)", + (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); } if (count != 0) db_printf("\n"); db_indent -= 2; } /* XXX. */ #undef count /* XXX need this non-static entry for calling from vm_map_print. */ void vm_object_print( /* db_expr_t */ long addr, boolean_t have_addr, /* db_expr_t */ long count, char *modif) { vm_object_print_static(addr, have_addr, count, modif); } DB_SHOW_COMMAND(vmopag, vm_object_print_pages) { vm_object_t object; vm_pindex_t fidx; vm_paddr_t pa; vm_page_t m, prev_m; int rcount, nl, c; nl = 0; TAILQ_FOREACH(object, &vm_object_list, object_list) { db_printf("new object: %p\n", (void *)object); if (nl > 18) { c = cngetc(); if (c != ' ') return; nl = 0; } nl++; rcount = 0; fidx = 0; pa = -1; TAILQ_FOREACH(m, &object->memq, listq) { if (m->pindex > 128) break; if ((prev_m = TAILQ_PREV(m, pglist, listq)) != NULL && prev_m->pindex + 1 != m->pindex) { if (rcount) { db_printf(" index(%ld)run(%d)pa(0x%lx)\n", (long)fidx, rcount, (long)pa); if (nl > 18) { c = cngetc(); if (c != ' ') return; nl = 0; } nl++; rcount = 0; } } if (rcount && (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { ++rcount; continue; } if (rcount) { db_printf(" index(%ld)run(%d)pa(0x%lx)\n", (long)fidx, rcount, (long)pa); if (nl > 18) { c = cngetc(); if (c != ' ') return; nl = 0; } nl++; } fidx = m->pindex; pa = VM_PAGE_TO_PHYS(m); rcount = 1; } if (rcount) { db_printf(" index(%ld)run(%d)pa(0x%lx)\n", (long)fidx, rcount, (long)pa); if (nl > 18) { c = cngetc(); if (c != ' ') return; nl = 0; } nl++; } } } #endif /* DDB */ Index: user/attilio/vmc-playground/sys/vm/vm_page.c =================================================================== --- user/attilio/vmc-playground/sys/vm/vm_page.c (revision 246331) +++ user/attilio/vmc-playground/sys/vm/vm_page.c (revision 246332) @@ -1,2818 +1,2818 @@ /*- * Copyright (c) 1991 Regents of the University of California. * All rights reserved. * Copyright (c) 1998 Matthew Dillon. All Rights Reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 */ /*- * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * Authors: Avadis Tevanian, Jr., Michael Wayne Young * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ /* * GENERAL RULES ON VM_PAGE MANIPULATION * * - A page queue lock is required when adding or removing a page from a * page queue (vm_pagequeues[]), regardless of other locks or the * busy state of a page. * * * In general, no thread besides the page daemon can acquire or * hold more than one page queue lock at a time. * * * The page daemon can acquire and hold any pair of page queue * locks in any order. * * - The object mutex is held when inserting or removing * pages from an object (vm_page_insert() or vm_page_remove()). * */ /* * Resident memory management module. */ #include __FBSDID("$FreeBSD$"); #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Associated with page of user-allocatable memory is a * page structure. */ struct vm_pagequeue vm_pagequeues[PQ_COUNT] = { [PQ_INACTIVE] = { .pq_pl = TAILQ_HEAD_INITIALIZER( vm_pagequeues[PQ_INACTIVE].pq_pl), .pq_cnt = &cnt.v_inactive_count, .pq_name = "vm inactive pagequeue" }, [PQ_ACTIVE] = { .pq_pl = TAILQ_HEAD_INITIALIZER( vm_pagequeues[PQ_ACTIVE].pq_pl), .pq_cnt = &cnt.v_active_count, .pq_name = "vm active pagequeue" } }; struct mtx_padalign vm_page_queue_free_mtx; struct mtx_padalign pa_lock[PA_LOCK_COUNT]; vm_page_t vm_page_array; long vm_page_array_size; long first_page; int vm_page_zero_count; static int boot_pages = UMA_BOOT_PAGES; TUNABLE_INT("vm.boot_pages", &boot_pages); SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RD, &boot_pages, 0, "number of pages allocated for bootstrapping the VM system"); static int pa_tryrelock_restart; SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD, &pa_tryrelock_restart, 0, "Number of tryrelock restarts"); static uma_zone_t fakepg_zone; static struct vnode *vm_page_alloc_init(vm_page_t m); static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits); static void vm_page_enqueue(int queue, vm_page_t m); static void vm_page_init_fakepg(void *dummy); SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init_fakepg, NULL); static void vm_page_init_fakepg(void *dummy) { fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); } /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */ #if PAGE_SIZE == 32768 #ifdef CTASSERT CTASSERT(sizeof(u_long) >= 8); #endif #endif /* * Try to acquire a physical address lock while a pmap is locked. If we * fail to trylock we unlock and lock the pmap directly and cache the * locked pa in *locked. The caller should then restart their loop in case * the virtual to physical mapping has changed. */ int vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked) { vm_paddr_t lockpa; lockpa = *locked; *locked = pa; if (lockpa) { PA_LOCK_ASSERT(lockpa, MA_OWNED); if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa)) return (0); PA_UNLOCK(lockpa); } if (PA_TRYLOCK(pa)) return (0); PMAP_UNLOCK(pmap); atomic_add_int(&pa_tryrelock_restart, 1); PA_LOCK(pa); PMAP_LOCK(pmap); return (EAGAIN); } /* * vm_set_page_size: * * Sets the page size, perhaps based upon the memory * size. Must be called before any use of page-size * dependent functions. */ void vm_set_page_size(void) { if (cnt.v_page_size == 0) cnt.v_page_size = PAGE_SIZE; if (((cnt.v_page_size - 1) & cnt.v_page_size) != 0) panic("vm_set_page_size: page size not a power of two"); } /* * vm_page_blacklist_lookup: * * See if a physical address in this page has been listed * in the blacklist tunable. Entries in the tunable are * separated by spaces or commas. If an invalid integer is * encountered then the rest of the string is skipped. */ static int vm_page_blacklist_lookup(char *list, vm_paddr_t pa) { vm_paddr_t bad; char *cp, *pos; for (pos = list; *pos != '\0'; pos = cp) { bad = strtoq(pos, &cp, 0); if (*cp != '\0') { if (*cp == ' ' || *cp == ',') { cp++; if (cp == pos) continue; } else break; } if (pa == trunc_page(bad)) return (1); } return (0); } /* * vm_page_startup: * * Initializes the resident memory module. * * Allocates memory for the page cells, and * for the object/offset-to-page hash table headers. * Each page cell is initialized and placed on the free list. */ vm_offset_t vm_page_startup(vm_offset_t vaddr) { vm_offset_t mapped; vm_paddr_t page_range; vm_paddr_t new_end; int i; vm_paddr_t pa; vm_paddr_t last_pa; char *list; /* the biggest memory array is the second group of pages */ vm_paddr_t end; vm_paddr_t biggestsize; vm_paddr_t low_water, high_water; int biggestone; biggestsize = 0; biggestone = 0; vaddr = round_page(vaddr); for (i = 0; phys_avail[i + 1]; i += 2) { phys_avail[i] = round_page(phys_avail[i]); phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); } low_water = phys_avail[0]; high_water = phys_avail[1]; for (i = 0; phys_avail[i + 1]; i += 2) { vm_paddr_t size = phys_avail[i + 1] - phys_avail[i]; if (size > biggestsize) { biggestone = i; biggestsize = size; } if (phys_avail[i] < low_water) low_water = phys_avail[i]; if (phys_avail[i + 1] > high_water) high_water = phys_avail[i + 1]; } #ifdef XEN low_water = 0; #endif end = phys_avail[biggestone+1]; /* * Initialize the page and queue locks. */ - mtx_init(&vm_page_queue_free_mtx, "vm page queue free mutex", NULL, - MTX_DEF | MTX_RECURSE); - - /* Setup page locks. */ + mtx_init(&vm_page_queue_free_mtx, "vm page free queue", NULL, MTX_DEF | + MTX_RECURSE); for (i = 0; i < PA_LOCK_COUNT; i++) mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF); for (i = 0; i < PQ_COUNT; i++) vm_pagequeue_init_lock(&vm_pagequeues[i]); + /* * Allocate memory for use when boot strapping the kernel memory * allocator. */ new_end = end - (boot_pages * UMA_SLAB_SIZE); new_end = trunc_page(new_end); mapped = pmap_map(&vaddr, new_end, end, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)mapped, end - new_end); uma_startup((void *)mapped, boot_pages); #if defined(__amd64__) || defined(__i386__) || defined(__arm__) || \ defined(__mips__) /* * Allocate a bitmap to indicate that a random physical page * needs to be included in a minidump. * * The amd64 port needs this to indicate which direct map pages * need to be dumped, via calls to dump_add_page()/dump_drop_page(). * * However, i386 still needs this workspace internally within the * minidump code. In theory, they are not needed on i386, but are * included should the sf_buf code decide to use them. */ last_pa = 0; for (i = 0; dump_avail[i + 1] != 0; i += 2) if (dump_avail[i + 1] > last_pa) last_pa = dump_avail[i + 1]; page_range = last_pa / PAGE_SIZE; vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY); new_end -= vm_page_dump_size; vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); bzero((void *)vm_page_dump, vm_page_dump_size); #endif #ifdef __amd64__ /* * Request that the physical pages underlying the message buffer be * included in a crash dump. Since the message buffer is accessed * through the direct map, they are not automatically included. */ pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); last_pa = pa + round_page(msgbufsize); while (pa < last_pa) { dump_add_page(pa); pa += PAGE_SIZE; } #endif /* * Compute the number of pages of memory that will be available for * use (taking into account the overhead of a page structure per * page). */ first_page = low_water / PAGE_SIZE; #ifdef VM_PHYSSEG_SPARSE page_range = 0; for (i = 0; phys_avail[i + 1] != 0; i += 2) page_range += atop(phys_avail[i + 1] - phys_avail[i]); #elif defined(VM_PHYSSEG_DENSE) page_range = high_water / PAGE_SIZE - first_page; #else #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." #endif end = new_end; /* * Reserve an unmapped guard page to trap access to vm_page_array[-1]. */ vaddr += PAGE_SIZE; /* * Initialize the mem entry structures now, and put them in the free * queue. */ new_end = trunc_page(end - page_range * sizeof(struct vm_page)); mapped = pmap_map(&vaddr, new_end, end, VM_PROT_READ | VM_PROT_WRITE); vm_page_array = (vm_page_t) mapped; #if VM_NRESERVLEVEL > 0 /* * Allocate memory for the reservation management system's data * structures. */ new_end = vm_reserv_startup(&vaddr, new_end, high_water); #endif #if defined(__amd64__) || defined(__mips__) /* * pmap_map on amd64 and mips can come out of the direct-map, not kvm * like i386, so the pages must be tracked for a crashdump to include * this data. This includes the vm_page_array and the early UMA * bootstrap pages. */ for (pa = new_end; pa < phys_avail[biggestone + 1]; pa += PAGE_SIZE) dump_add_page(pa); #endif phys_avail[biggestone + 1] = new_end; /* * Clear all of the page structures */ bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); for (i = 0; i < page_range; i++) vm_page_array[i].order = VM_NFREEORDER; vm_page_array_size = page_range; /* * Initialize the physical memory allocator. */ vm_phys_init(); /* * Add every available physical page that is not blacklisted to * the free lists. */ cnt.v_page_count = 0; cnt.v_free_count = 0; list = getenv("vm.blacklist"); for (i = 0; phys_avail[i + 1] != 0; i += 2) { pa = phys_avail[i]; last_pa = phys_avail[i + 1]; while (pa < last_pa) { if (list != NULL && vm_page_blacklist_lookup(list, pa)) printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa); else vm_phys_add_page(pa); pa += PAGE_SIZE; } } freeenv(list); #if VM_NRESERVLEVEL > 0 /* * Initialize the reservation management system. */ vm_reserv_init(); #endif return (vaddr); } void vm_page_reference(vm_page_t m) { vm_page_aflag_set(m, PGA_REFERENCED); } void vm_page_busy(vm_page_t m) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); KASSERT((m->oflags & VPO_BUSY) == 0, ("vm_page_busy: page already busy!!!")); m->oflags |= VPO_BUSY; } /* * vm_page_flash: * * wakeup anyone waiting for the page. */ void vm_page_flash(vm_page_t m) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (m->oflags & VPO_WANTED) { m->oflags &= ~VPO_WANTED; wakeup(m); } } /* * vm_page_wakeup: * * clear the VPO_BUSY flag and wakeup anyone waiting for the * page. * */ void vm_page_wakeup(vm_page_t m) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); KASSERT(m->oflags & VPO_BUSY, ("vm_page_wakeup: page not busy!!!")); m->oflags &= ~VPO_BUSY; vm_page_flash(m); } void vm_page_io_start(vm_page_t m) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); m->busy++; } void vm_page_io_finish(vm_page_t m) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); KASSERT(m->busy > 0, ("vm_page_io_finish: page %p is not busy", m)); m->busy--; if (m->busy == 0) vm_page_flash(m); } /* * Keep page from being freed by the page daemon * much of the same effect as wiring, except much lower * overhead and should be used only for *very* temporary * holding ("wiring"). */ void vm_page_hold(vm_page_t mem) { vm_page_lock_assert(mem, MA_OWNED); mem->hold_count++; } void vm_page_unhold(vm_page_t mem) { vm_page_lock_assert(mem, MA_OWNED); --mem->hold_count; KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!")); if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) vm_page_free_toq(mem); } /* * vm_page_unhold_pages: * * Unhold each of the pages that is referenced by the given array. */ void vm_page_unhold_pages(vm_page_t *ma, int count) { struct mtx *mtx, *new_mtx; mtx = NULL; for (; count != 0; count--) { /* * Avoid releasing and reacquiring the same page lock. */ new_mtx = vm_page_lockptr(*ma); if (mtx != new_mtx) { if (mtx != NULL) mtx_unlock(mtx); mtx = new_mtx; mtx_lock(mtx); } vm_page_unhold(*ma); ma++; } if (mtx != NULL) mtx_unlock(mtx); } vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa) { vm_page_t m; #ifdef VM_PHYSSEG_SPARSE m = vm_phys_paddr_to_vm_page(pa); if (m == NULL) m = vm_phys_fictitious_to_vm_page(pa); return (m); #elif defined(VM_PHYSSEG_DENSE) long pi; pi = atop(pa); if (pi >= first_page && (pi - first_page) < vm_page_array_size) { m = &vm_page_array[pi - first_page]; return (m); } return (vm_phys_fictitious_to_vm_page(pa)); #else #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." #endif } /* * vm_page_getfake: * * Create a fictitious page with the specified physical address and * memory attribute. The memory attribute is the only the machine- * dependent aspect of a fictitious page that must be initialized. */ vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) { vm_page_t m; m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); vm_page_initfake(m, paddr, memattr); return (m); } void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) { if ((m->flags & PG_FICTITIOUS) != 0) { /* * The page's memattr might have changed since the * previous initialization. Update the pmap to the * new memattr. */ goto memattr; } m->phys_addr = paddr; m->queue = PQ_NONE; /* Fictitious pages don't use "segind". */ m->flags = PG_FICTITIOUS; /* Fictitious pages don't use "order" or "pool". */ m->oflags = VPO_BUSY | VPO_UNMANAGED; m->wire_count = 1; memattr: pmap_page_set_memattr(m, memattr); } /* * vm_page_putfake: * * Release a fictitious page. */ void vm_page_putfake(vm_page_t m) { KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); KASSERT((m->flags & PG_FICTITIOUS) != 0, ("vm_page_putfake: bad page %p", m)); uma_zfree(fakepg_zone, m); } /* * vm_page_updatefake: * * Update the given fictitious page to the specified physical address and * memory attribute. */ void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) { KASSERT((m->flags & PG_FICTITIOUS) != 0, ("vm_page_updatefake: bad page %p", m)); m->phys_addr = paddr; pmap_page_set_memattr(m, memattr); } /* * vm_page_free: * * Free a page. */ void vm_page_free(vm_page_t m) { m->flags &= ~PG_ZERO; vm_page_free_toq(m); } /* * vm_page_free_zero: * * Free a page to the zerod-pages queue */ void vm_page_free_zero(vm_page_t m) { m->flags |= PG_ZERO; vm_page_free_toq(m); } /* * Unbusy and handle the page queueing for a page from the VOP_GETPAGES() * array which is not the request page. */ void vm_page_readahead_finish(vm_page_t m) { if (m->valid != 0) { /* * Since the page is not the requested page, whether * it should be activated or deactivated is not * obvious. Empirical results have shown that * deactivating the page is usually the best choice, * unless the page is wanted by another thread. */ if (m->oflags & VPO_WANTED) { vm_page_lock(m); vm_page_activate(m); vm_page_unlock(m); } else { vm_page_lock(m); vm_page_deactivate(m); vm_page_unlock(m); } vm_page_wakeup(m); } else { /* * Free the completely invalid page. Such page state * occurs due to the short read operation which did * not covered our page at all, or in case when a read * error happens. */ vm_page_lock(m); vm_page_free(m); vm_page_unlock(m); } } /* * vm_page_sleep: * * Sleep and release the page lock. * * The object containing the given page must be locked. */ void vm_page_sleep(vm_page_t m, const char *msg) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (mtx_owned(vm_page_lockptr(m))) vm_page_unlock(m); /* * It's possible that while we sleep, the page will get * unbusied and freed. If we are holding the object * lock, we will assume we hold a reference to the object * such that even if m->object changes, we can re-lock * it. */ m->oflags |= VPO_WANTED; msleep(m, VM_OBJECT_MTX(m->object), PVM, msg, 0); } /* * vm_page_dirty_KBI: [ internal use only ] * * Set all bits in the page's dirty field. * * The object containing the specified page must be locked if the * call is made from the machine-independent layer. * * See vm_page_clear_dirty_mask(). * * This function should only be called by vm_page_dirty(). */ void vm_page_dirty_KBI(vm_page_t m) { /* These assertions refer to this operation by its public name. */ KASSERT((m->flags & PG_CACHED) == 0, ("vm_page_dirty: page in cache!")); KASSERT(!VM_PAGE_IS_FREE(m), ("vm_page_dirty: page is free!")); KASSERT(m->valid == VM_PAGE_BITS_ALL, ("vm_page_dirty: page is invalid!")); m->dirty = VM_PAGE_BITS_ALL; } /* * vm_page_insert: [ internal use only ] * * Inserts the given mem entry into the object and object list. * * The pagetables are not updated but will presumably fault the page * in if necessary, or if a kernel page the caller will at some point * enter the page into the kernel's pmap. We are not allowed to sleep * here so we *can't* do this anyway. * * The object must be locked. */ void vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) { vm_page_t neighbor; + VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); if (m->object != NULL) panic("vm_page_insert: page already inserted"); /* * Record the object/offset pair in this page */ m->object = object; m->pindex = pindex; if (object->resident_page_count == 0) { TAILQ_INSERT_TAIL(&object->memq, m, listq); } else { neighbor = vm_radix_lookup_ge(&object->rtree, pindex); if (neighbor != NULL) { KASSERT(pindex < neighbor->pindex, ("vm_page_insert: offset %ju not minor than %ju", (uintmax_t)pindex, (uintmax_t)neighbor->pindex)); TAILQ_INSERT_BEFORE(neighbor, m, listq); } else TAILQ_INSERT_TAIL(&object->memq, m, listq); } if (vm_radix_insert(&object->rtree, pindex, m) != 0) panic("vm_page_insert: unable to insert the new page"); /* * Show that the object has one more resident page. */ object->resident_page_count++; /* * Hold the vnode until the last page is released. */ if (object->resident_page_count == 1 && object->type == OBJT_VNODE) vhold(object->handle); /* * Since we are inserting a new and possibly dirty page, * update the object's OBJ_MIGHTBEDIRTY flag. */ if (pmap_page_is_write_mapped(m)) vm_object_set_writeable_dirty(object); } /* * vm_page_remove: * * Removes the given mem entry from the object/offset-page * table and the object page list, but do not invalidate/terminate * the backing store. * * The underlying pmap entry (if any) is NOT removed here. * * The object must be locked. The page must be locked if it is managed. */ void vm_page_remove(vm_page_t m) { vm_object_t object; if ((m->oflags & VPO_UNMANAGED) == 0) vm_page_lock_assert(m, MA_OWNED); if ((object = m->object) == NULL) return; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); if (m->oflags & VPO_BUSY) { m->oflags &= ~VPO_BUSY; vm_page_flash(m); } vm_radix_remove(&object->rtree, m->pindex); TAILQ_REMOVE(&object->memq, m, listq); /* * And show that the object has one fewer resident page. */ object->resident_page_count--; /* * The vnode may now be recycled. */ if (object->resident_page_count == 0 && object->type == OBJT_VNODE) vdrop(object->handle); m->object = NULL; } /* * vm_page_lookup: * * Returns the page associated with the object/offset * pair specified; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_lookup(vm_object_t object, vm_pindex_t pindex) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); return vm_radix_lookup(&object->rtree, pindex); } /* * vm_page_find_least: * * Returns the page associated with the object with least pindex * greater than or equal to the parameter pindex, or NULL. * * The object must be locked. */ vm_page_t vm_page_find_least(vm_object_t object, vm_pindex_t pindex) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); if (object->resident_page_count) return (vm_radix_lookup_ge(&object->rtree, pindex)); return (NULL); } /* * Returns the given page's successor (by pindex) within the object if it is * resident; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_next(vm_page_t m) { vm_page_t next; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if ((next = TAILQ_NEXT(m, listq)) != NULL && next->pindex != m->pindex + 1) next = NULL; return (next); } /* * Returns the given page's predecessor (by pindex) within the object if it is * resident; if none is found, NULL is returned. * * The object must be locked. */ vm_page_t vm_page_prev(vm_page_t m) { vm_page_t prev; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL && prev->pindex != m->pindex - 1) prev = NULL; return (prev); } /* * vm_page_rename: * * Move the given memory entry from its * current object to the specified target object/offset. * * Note: swap associated with the page must be invalidated by the move. We * have to do this for several reasons: (1) we aren't freeing the * page, (2) we are dirtying the page, (3) the VM system is probably * moving the page from object A to B, and will then later move * the backing store from A to B and we can't have a conflict. * * Note: we *always* dirty the page. It is necessary both for the * fact that we moved it, and because we may be invalidating * swap. If the page is on the cache, we have to deactivate it * or vm_page_dirty() will panic. Dirty pages are not allowed * on the cache. * * The objects must be locked. The page must be locked if it is managed. */ void vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) { vm_page_remove(m); vm_page_insert(m, new_object, new_pindex); vm_page_dirty(m); } /* * Returns the cached page that is associated with the given * object and offset. If, however, none exists, returns NULL. * * The free page queue must be locked. */ static inline vm_page_t vm_page_cache_lookup(vm_object_t object, vm_pindex_t pindex) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); if (!vm_object_cache_is_empty(object)) return (vm_radix_lookup(&object->cache, pindex)); return (NULL); } /* * Remove the given cached page from its containing object's * collection of cached pages. * * The free page queue must be locked. */ static void vm_page_cache_remove(vm_page_t m) { mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); KASSERT((m->flags & PG_CACHED) != 0, ("vm_page_cache_remove: page %p is not cached", m)); vm_radix_remove(&m->object->cache, m->pindex); m->object = NULL; cnt.v_cache_count--; } /* * Move a given cached page from an object's cached pages to * the free list. * * The free page queue mtx and object lock must be locked. */ void vm_page_cache_free(vm_page_t m) { vm_object_t object; object = m->object; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); KASSERT((m->flags & PG_CACHED) != 0, ("vm_page_cache_free: page %p is not cached", m)); /* * Replicate vm_page_cache_remove with a version that can collapse * internal nodes since the object lock is held. */ vm_radix_remove(&object->cache, m->pindex); m->object = NULL; m->valid = 0; /* Clear PG_CACHED and set PG_FREE. */ m->flags ^= PG_CACHED | PG_FREE; cnt.v_cache_count--; cnt.v_free_count++; } /* * Attempt to rename a cached page from one object to another. If * it fails the cached page is freed. */ void vm_page_cache_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t idx) { vm_object_t orig_object; orig_object = m->object; VM_OBJECT_LOCK_ASSERT(orig_object, MA_OWNED); VM_OBJECT_LOCK_ASSERT(new_object, MA_OWNED); mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); vm_radix_remove(&orig_object->cache, m->pindex); if (vm_radix_insert(&new_object->cache, idx, m) != 0) panic("vm_page_cache_rename: failed vm_radix_insert"); m->object = new_object; m->pindex = idx; } /* * Returns a pointer to the cached page associated with the given object * and offset, NULL otherwise. * * The object must be locked. */ vm_page_t vm_page_is_cached(vm_object_t object, vm_pindex_t pindex) { vm_page_t m; /* * Insertion into an object's collection of cached pages requires the * object to be locked. Therefore, if the object is locked and the * object's collection is empty, there is no need to acquire the free * page queues lock in order to prove that the specified page doesn't * exist. */ VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); mtx_lock(&vm_page_queue_free_mtx); m = vm_page_cache_lookup(object, pindex); mtx_unlock(&vm_page_queue_free_mtx); return (m); } /* * vm_page_alloc: * * Allocate and return a page that is associated with the specified * object and offset pair. By default, this page has the flag VPO_BUSY * set. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_COUNT(number) the number of additional pages that the caller * intends to allocate * VM_ALLOC_IFCACHED return page only if it is cached * VM_ALLOC_IFNOTCACHED return NULL, do not reactivate if the page * is cached * VM_ALLOC_NOBUSY do not set the flag VPO_BUSY on the page * VM_ALLOC_NODUMP do not include the page in a kernel core dump * VM_ALLOC_NOOBJ page is not associated with an object and * should not have the flag VPO_BUSY set * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page * * This routine may not sleep. */ vm_page_t vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) { struct vnode *vp = NULL; vm_object_t m_object; vm_page_t m; int flags, req_class; KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0), ("vm_page_alloc: inconsistent object/req")); if (object != NULL) VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); req_class = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) req_class = VM_ALLOC_SYSTEM; mtx_lock(&vm_page_queue_free_mtx); if (cnt.v_free_count + cnt.v_cache_count > cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && cnt.v_free_count + cnt.v_cache_count > cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && cnt.v_free_count + cnt.v_cache_count > 0)) { /* * Allocate from the free queue if the number of free pages * exceeds the minimum for the request class. */ if (object != NULL && (m = vm_page_cache_lookup(object, pindex)) != NULL) { if ((req & VM_ALLOC_IFNOTCACHED) != 0) { mtx_unlock(&vm_page_queue_free_mtx); return (NULL); } if (vm_phys_unfree_page(m)) vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, 0); #if VM_NRESERVLEVEL > 0 else if (!vm_reserv_reactivate_page(m)) #else else #endif panic("vm_page_alloc: cache page %p is missing" " from the free queue", m); } else if ((req & VM_ALLOC_IFCACHED) != 0) { mtx_unlock(&vm_page_queue_free_mtx); return (NULL); #if VM_NRESERVLEVEL > 0 } else if (object == NULL || (object->flags & (OBJ_COLORED | OBJ_FICTITIOUS)) != OBJ_COLORED || (m = vm_reserv_alloc_page(object, pindex)) == NULL) { #else } else { #endif m = vm_phys_alloc_pages(object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); #if VM_NRESERVLEVEL > 0 if (m == NULL && vm_reserv_reclaim_inactive()) { m = vm_phys_alloc_pages(object != NULL ? VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); } #endif } } else { /* * Not allocatable, give up. */ mtx_unlock(&vm_page_queue_free_mtx); atomic_add_int(&vm_pageout_deficit, max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); pagedaemon_wakeup(); return (NULL); } /* * At this point we had better have found a good page. */ KASSERT(m != NULL, ("vm_page_alloc: missing page")); KASSERT(m->queue == PQ_NONE, ("vm_page_alloc: page %p has unexpected queue %d", m, m->queue)); KASSERT(m->wire_count == 0, ("vm_page_alloc: page %p is wired", m)); KASSERT(m->hold_count == 0, ("vm_page_alloc: page %p is held", m)); KASSERT(m->busy == 0, ("vm_page_alloc: page %p is busy", m)); KASSERT(m->dirty == 0, ("vm_page_alloc: page %p is dirty", m)); KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("vm_page_alloc: page %p has unexpected memattr %d", m, pmap_page_get_memattr(m))); if ((m->flags & PG_CACHED) != 0) { KASSERT((m->flags & PG_ZERO) == 0, ("vm_page_alloc: cached page %p is PG_ZERO", m)); KASSERT(m->valid != 0, ("vm_page_alloc: cached page %p is invalid", m)); if (m->object == object && m->pindex == pindex) cnt.v_reactivated++; else m->valid = 0; m_object = m->object; vm_page_cache_remove(m); if (m_object->type == OBJT_VNODE && vm_object_cache_is_empty(m_object)) vp = m_object->handle; } else { KASSERT(VM_PAGE_IS_FREE(m), ("vm_page_alloc: page %p is not free", m)); KASSERT(m->valid == 0, ("vm_page_alloc: free page %p is valid", m)); cnt.v_free_count--; } /* * Only the PG_ZERO flag is inherited. The PG_CACHED or PG_FREE flag * must be cleared before the free page queues lock is released. */ flags = 0; if (m->flags & PG_ZERO) { vm_page_zero_count--; if (req & VM_ALLOC_ZERO) flags = PG_ZERO; } if (req & VM_ALLOC_NODUMP) flags |= PG_NODUMP; m->flags = flags; mtx_unlock(&vm_page_queue_free_mtx); m->aflags = 0; m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ)) == 0) m->oflags |= VPO_BUSY; if (req & VM_ALLOC_WIRED) { /* * The page lock is not required for wiring a page until that * page is inserted into the object. */ atomic_add_int(&cnt.v_wire_count, 1); m->wire_count = 1; } m->act_count = 0; if (object != NULL) { /* Ignore device objects; the pager sets "memattr" for them. */ if (object->memattr != VM_MEMATTR_DEFAULT && (object->flags & OBJ_FICTITIOUS) == 0) pmap_page_set_memattr(m, object->memattr); vm_page_insert(m, object, pindex); } else m->pindex = pindex; /* * The following call to vdrop() must come after the above call * to vm_page_insert() in case both affect the same object and * vnode. Otherwise, the affected vnode's hold count could * temporarily become zero. */ if (vp != NULL) vdrop(vp); /* * Don't wakeup too often - wakeup the pageout daemon when * we would be nearly out of memory. */ if (vm_paging_needed()) pagedaemon_wakeup(); return (m); } /* * vm_page_alloc_contig: * * Allocate a contiguous set of physical pages of the given size "npages" * from the free lists. All of the physical pages must be at or above * the given physical address "low" and below the given physical address * "high". The given value "alignment" determines the alignment of the * first physical page in the set. If the given value "boundary" is * non-zero, then the set of physical pages cannot cross any physical * address boundary that is a multiple of that value. Both "alignment" * and "boundary" must be a power of two. * * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, * then the memory attribute setting for the physical pages is configured * to the object's memory attribute setting. Otherwise, the memory * attribute setting for the physical pages is configured to "memattr", * overriding the object's memory attribute setting. However, if the * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the * memory attribute setting for the physical pages cannot be configured * to VM_MEMATTR_DEFAULT. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_NOBUSY do not set the flag VPO_BUSY on the page * VM_ALLOC_NOOBJ page is not associated with an object and * should not have the flag VPO_BUSY set * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page * * This routine may not sleep. */ vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) { struct vnode *drop; vm_page_t deferred_vdrop_list, m, m_ret; u_int flags, oflags; int req_class; KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0), ("vm_page_alloc_contig: inconsistent object/req")); if (object != NULL) { VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT(object->type == OBJT_PHYS, ("vm_page_alloc_contig: object %p isn't OBJT_PHYS", object)); } KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); req_class = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) req_class = VM_ALLOC_SYSTEM; deferred_vdrop_list = NULL; mtx_lock(&vm_page_queue_free_mtx); if (cnt.v_free_count + cnt.v_cache_count >= npages + cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && cnt.v_free_count + cnt.v_cache_count >= npages + cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && cnt.v_free_count + cnt.v_cache_count >= npages)) { #if VM_NRESERVLEVEL > 0 retry: if (object == NULL || (object->flags & OBJ_COLORED) == 0 || (m_ret = vm_reserv_alloc_contig(object, pindex, npages, low, high, alignment, boundary)) == NULL) #endif m_ret = vm_phys_alloc_contig(npages, low, high, alignment, boundary); } else { mtx_unlock(&vm_page_queue_free_mtx); atomic_add_int(&vm_pageout_deficit, npages); pagedaemon_wakeup(); return (NULL); } if (m_ret != NULL) for (m = m_ret; m < &m_ret[npages]; m++) { drop = vm_page_alloc_init(m); if (drop != NULL) { /* * Enqueue the vnode for deferred vdrop(). * * Once the pages are removed from the free * page list, "pageq" can be safely abused to * construct a short-lived list of vnodes. */ m->pageq.tqe_prev = (void *)drop; m->pageq.tqe_next = deferred_vdrop_list; deferred_vdrop_list = m; } } else { #if VM_NRESERVLEVEL > 0 if (vm_reserv_reclaim_contig(npages, low, high, alignment, boundary)) goto retry; #endif } mtx_unlock(&vm_page_queue_free_mtx); if (m_ret == NULL) return (NULL); /* * Initialize the pages. Only the PG_ZERO flag is inherited. */ flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; if ((req & VM_ALLOC_NODUMP) != 0) flags |= PG_NODUMP; if ((req & VM_ALLOC_WIRED) != 0) atomic_add_int(&cnt.v_wire_count, npages); oflags = VPO_UNMANAGED; if (object != NULL) { if ((req & VM_ALLOC_NOBUSY) == 0) oflags |= VPO_BUSY; if (object->memattr != VM_MEMATTR_DEFAULT && memattr == VM_MEMATTR_DEFAULT) memattr = object->memattr; } for (m = m_ret; m < &m_ret[npages]; m++) { m->aflags = 0; m->flags = (m->flags | PG_NODUMP) & flags; if ((req & VM_ALLOC_WIRED) != 0) m->wire_count = 1; /* Unmanaged pages don't use "act_count". */ m->oflags = oflags; if (memattr != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, memattr); if (object != NULL) vm_page_insert(m, object, pindex); else m->pindex = pindex; pindex++; } while (deferred_vdrop_list != NULL) { vdrop((struct vnode *)deferred_vdrop_list->pageq.tqe_prev); deferred_vdrop_list = deferred_vdrop_list->pageq.tqe_next; } if (vm_paging_needed()) pagedaemon_wakeup(); return (m_ret); } /* * Initialize a page that has been freshly dequeued from a freelist. * The caller has to drop the vnode returned, if it is not NULL. * * This function may only be used to initialize unmanaged pages. * * To be called with vm_page_queue_free_mtx held. */ static struct vnode * vm_page_alloc_init(vm_page_t m) { struct vnode *drop; vm_object_t m_object; KASSERT(m->queue == PQ_NONE, ("vm_page_alloc_init: page %p has unexpected queue %d", m, m->queue)); KASSERT(m->wire_count == 0, ("vm_page_alloc_init: page %p is wired", m)); KASSERT(m->hold_count == 0, ("vm_page_alloc_init: page %p is held", m)); KASSERT(m->busy == 0, ("vm_page_alloc_init: page %p is busy", m)); KASSERT(m->dirty == 0, ("vm_page_alloc_init: page %p is dirty", m)); KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, ("vm_page_alloc_init: page %p has unexpected memattr %d", m, pmap_page_get_memattr(m))); mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); drop = NULL; if ((m->flags & PG_CACHED) != 0) { KASSERT((m->flags & PG_ZERO) == 0, ("vm_page_alloc_init: cached page %p is PG_ZERO", m)); m->valid = 0; m_object = m->object; vm_page_cache_remove(m); if (m_object->type == OBJT_VNODE && vm_object_cache_is_empty(m_object)) drop = m_object->handle; } else { KASSERT(VM_PAGE_IS_FREE(m), ("vm_page_alloc_init: page %p is not free", m)); KASSERT(m->valid == 0, ("vm_page_alloc_init: free page %p is valid", m)); cnt.v_free_count--; if ((m->flags & PG_ZERO) != 0) vm_page_zero_count--; } /* Don't clear the PG_ZERO flag; we'll need it later. */ m->flags &= PG_ZERO; return (drop); } /* * vm_page_alloc_freelist: * * Allocate a physical page from the specified free page list. * * The caller must always specify an allocation class. * * allocation classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * * optional allocation flags: * VM_ALLOC_COUNT(number) the number of additional pages that the caller * intends to allocate * VM_ALLOC_WIRED wire the allocated page * VM_ALLOC_ZERO prefer a zeroed page * * This routine may not sleep. */ vm_page_t vm_page_alloc_freelist(int flind, int req) { struct vnode *drop; vm_page_t m; u_int flags; int req_class; req_class = req & VM_ALLOC_CLASS_MASK; /* * The page daemon is allowed to dig deeper into the free page list. */ if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) req_class = VM_ALLOC_SYSTEM; /* * Do not allocate reserved pages unless the req has asked for it. */ mtx_lock(&vm_page_queue_free_mtx); if (cnt.v_free_count + cnt.v_cache_count > cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && cnt.v_free_count + cnt.v_cache_count > cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && cnt.v_free_count + cnt.v_cache_count > 0)) m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0); else { mtx_unlock(&vm_page_queue_free_mtx); atomic_add_int(&vm_pageout_deficit, max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); pagedaemon_wakeup(); return (NULL); } if (m == NULL) { mtx_unlock(&vm_page_queue_free_mtx); return (NULL); } drop = vm_page_alloc_init(m); mtx_unlock(&vm_page_queue_free_mtx); /* * Initialize the page. Only the PG_ZERO flag is inherited. */ m->aflags = 0; flags = 0; if ((req & VM_ALLOC_ZERO) != 0) flags = PG_ZERO; m->flags &= flags; if ((req & VM_ALLOC_WIRED) != 0) { /* * The page lock is not required for wiring a page that does * not belong to an object. */ atomic_add_int(&cnt.v_wire_count, 1); m->wire_count = 1; } /* Unmanaged pages don't use "act_count". */ m->oflags = VPO_UNMANAGED; if (drop != NULL) vdrop(drop); if (vm_paging_needed()) pagedaemon_wakeup(); return (m); } /* * vm_wait: (also see VM_WAIT macro) * * Sleep until free pages are available for allocation. * - Called in various places before memory allocations. */ void vm_wait(void) { mtx_lock(&vm_page_queue_free_mtx); if (curproc == pageproc) { vm_pageout_pages_needed = 1; msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx, PDROP | PSWP, "VMWait", 0); } else { if (!vm_pages_needed) { vm_pages_needed = 1; wakeup(&vm_pages_needed); } msleep(&cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM, "vmwait", 0); } } /* * vm_waitpfault: (also see VM_WAITPFAULT macro) * * Sleep until free pages are available for allocation. * - Called only in vm_fault so that processes page faulting * can be easily tracked. * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing * processes will be able to grab memory first. Do not change * this balance without careful testing first. */ void vm_waitpfault(void) { mtx_lock(&vm_page_queue_free_mtx); if (!vm_pages_needed) { vm_pages_needed = 1; wakeup(&vm_pages_needed); } msleep(&cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER, "pfault", 0); } /* * vm_page_dequeue: * * Remove the given page from its current page queue. * * The page must be locked. */ void vm_page_dequeue(vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); KASSERT(m->queue != PQ_NONE, ("vm_page_dequeue: page %p is not queued", m)); pq = &vm_pagequeues[m->queue]; vm_pagequeue_lock(pq); m->queue = PQ_NONE; TAILQ_REMOVE(&pq->pq_pl, m, pageq); (*pq->pq_cnt)--; vm_pagequeue_unlock(pq); } /* * vm_page_dequeue_locked: * * Remove the given page from its current page queue. * * The page and page queue must be locked. */ void vm_page_dequeue_locked(vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); pq = &vm_pagequeues[m->queue]; vm_pagequeue_assert_locked(pq); m->queue = PQ_NONE; TAILQ_REMOVE(&pq->pq_pl, m, pageq); (*pq->pq_cnt)--; } /* * vm_page_enqueue: * * Add the given page to the specified page queue. * * The page must be locked. */ static void vm_page_enqueue(int queue, vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); pq = &vm_pagequeues[queue]; vm_pagequeue_lock(pq); m->queue = queue; TAILQ_INSERT_TAIL(&pq->pq_pl, m, pageq); ++*pq->pq_cnt; vm_pagequeue_unlock(pq); } /* * vm_page_requeue: * * Move the given page to the tail of its current page queue. * * The page must be locked. */ void vm_page_requeue(vm_page_t m) { struct vm_pagequeue *pq; vm_page_lock_assert(m, MA_OWNED); KASSERT(m->queue != PQ_NONE, ("vm_page_requeue: page %p is not queued", m)); pq = &vm_pagequeues[m->queue]; vm_pagequeue_lock(pq); TAILQ_REMOVE(&pq->pq_pl, m, pageq); TAILQ_INSERT_TAIL(&pq->pq_pl, m, pageq); vm_pagequeue_unlock(pq); } /* * vm_page_requeue_locked: * * Move the given page to the tail of its current page queue. * * The page queue must be locked. */ void vm_page_requeue_locked(vm_page_t m) { struct vm_pagequeue *pq; KASSERT(m->queue != PQ_NONE, ("vm_page_requeue_locked: page %p is not queued", m)); pq = &vm_pagequeues[m->queue]; vm_pagequeue_assert_locked(pq); TAILQ_REMOVE(&pq->pq_pl, m, pageq); TAILQ_INSERT_TAIL(&pq->pq_pl, m, pageq); } /* * vm_page_activate: * * Put the specified page on the active list (if appropriate). * Ensure that act_count is at least ACT_INIT but do not otherwise * mess with it. * * The page must be locked. */ void vm_page_activate(vm_page_t m) { int queue; vm_page_lock_assert(m, MA_OWNED); VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if ((queue = m->queue) != PQ_ACTIVE) { if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { if (m->act_count < ACT_INIT) m->act_count = ACT_INIT; if (queue != PQ_NONE) vm_page_dequeue(m); vm_page_enqueue(PQ_ACTIVE, m); } else KASSERT(queue == PQ_NONE, ("vm_page_activate: wired page %p is queued", m)); } else { if (m->act_count < ACT_INIT) m->act_count = ACT_INIT; } } /* * vm_page_free_wakeup: * * Helper routine for vm_page_free_toq() and vm_page_cache(). This * routine is called when a page has been added to the cache or free * queues. * * The page queues must be locked. */ static inline void vm_page_free_wakeup(void) { mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); /* * if pageout daemon needs pages, then tell it that there are * some free. */ if (vm_pageout_pages_needed && cnt.v_cache_count + cnt.v_free_count >= cnt.v_pageout_free_min) { wakeup(&vm_pageout_pages_needed); vm_pageout_pages_needed = 0; } /* * wakeup processes that are waiting on memory if we hit a * high water mark. And wakeup scheduler process if we have * lots of memory. this process will swapin processes. */ if (vm_pages_needed && !vm_page_count_min()) { vm_pages_needed = 0; wakeup(&cnt.v_free_count); } } /* * vm_page_free_toq: * * Returns the given page to the free list, * disassociating it with any VM object. * * The object must be locked. The page must be locked if it is managed. */ void vm_page_free_toq(vm_page_t m) { if ((m->oflags & VPO_UNMANAGED) == 0) { vm_page_lock_assert(m, MA_OWNED); KASSERT(!pmap_page_is_mapped(m), ("vm_page_free_toq: freeing mapped page %p", m)); } else KASSERT(m->queue == PQ_NONE, ("vm_page_free_toq: unmanaged page %p is queued", m)); PCPU_INC(cnt.v_tfree); if (VM_PAGE_IS_FREE(m)) panic("vm_page_free: freeing free page %p", m); else if (m->busy != 0) panic("vm_page_free: freeing busy page %p", m); /* * Unqueue, then remove page. Note that we cannot destroy * the page here because we do not want to call the pager's * callback routine until after we've put the page on the * appropriate free queue. */ vm_page_remque(m); vm_page_remove(m); /* * If fictitious remove object association and * return, otherwise delay object association removal. */ if ((m->flags & PG_FICTITIOUS) != 0) { return; } m->valid = 0; vm_page_undirty(m); if (m->wire_count != 0) panic("vm_page_free: freeing wired page %p", m); if (m->hold_count != 0) { m->flags &= ~PG_ZERO; KASSERT((m->flags & PG_UNHOLDFREE) == 0, ("vm_page_free: freeing PG_UNHOLDFREE page %p", m)); m->flags |= PG_UNHOLDFREE; } else { /* * Restore the default memory attribute to the page. */ if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); /* * Insert the page into the physical memory allocator's * cache/free page queues. */ mtx_lock(&vm_page_queue_free_mtx); m->flags |= PG_FREE; cnt.v_free_count++; #if VM_NRESERVLEVEL > 0 if (!vm_reserv_free_page(m)) #else if (TRUE) #endif vm_phys_free_pages(m, 0); if ((m->flags & PG_ZERO) != 0) ++vm_page_zero_count; else vm_page_zero_idle_wakeup(); vm_page_free_wakeup(); mtx_unlock(&vm_page_queue_free_mtx); } } /* * vm_page_wire: * * Mark this page as wired down by yet * another map, removing it from paging queues * as necessary. * * If the page is fictitious, then its wire count must remain one. * * The page must be locked. */ void vm_page_wire(vm_page_t m) { /* * Only bump the wire statistics if the page is not already wired, * and only unqueue the page if it is on some queue (if it is unmanaged * it is already off the queues). */ vm_page_lock_assert(m, MA_OWNED); if ((m->flags & PG_FICTITIOUS) != 0) { KASSERT(m->wire_count == 1, ("vm_page_wire: fictitious page %p's wire count isn't one", m)); return; } if (m->wire_count == 0) { KASSERT((m->oflags & VPO_UNMANAGED) == 0 || m->queue == PQ_NONE, ("vm_page_wire: unmanaged page %p is queued", m)); vm_page_remque(m); atomic_add_int(&cnt.v_wire_count, 1); } m->wire_count++; KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); } /* * vm_page_unwire: * * Release one wiring of the specified page, potentially enabling it to be * paged again. If paging is enabled, then the value of the parameter * "activate" determines to which queue the page is added. If "activate" is * non-zero, then the page is added to the active queue. Otherwise, it is * added to the inactive queue. * * However, unless the page belongs to an object, it is not enqueued because * it cannot be paged out. * * If a page is fictitious, then its wire count must alway be one. * * A managed page must be locked. */ void vm_page_unwire(vm_page_t m, int activate) { if ((m->oflags & VPO_UNMANAGED) == 0) vm_page_lock_assert(m, MA_OWNED); if ((m->flags & PG_FICTITIOUS) != 0) { KASSERT(m->wire_count == 1, ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); return; } if (m->wire_count > 0) { m->wire_count--; if (m->wire_count == 0) { atomic_subtract_int(&cnt.v_wire_count, 1); if ((m->oflags & VPO_UNMANAGED) != 0 || m->object == NULL) return; if (!activate) m->flags &= ~PG_WINATCFLS; vm_page_enqueue(activate ? PQ_ACTIVE : PQ_INACTIVE, m); } } else panic("vm_page_unwire: page %p's wire count is zero", m); } /* * Move the specified page to the inactive queue. * * Many pages placed on the inactive queue should actually go * into the cache, but it is difficult to figure out which. What * we do instead, if the inactive target is well met, is to put * clean pages at the head of the inactive queue instead of the tail. * This will cause them to be moved to the cache more quickly and * if not actively re-referenced, reclaimed more quickly. If we just * stick these pages at the end of the inactive queue, heavy filesystem * meta-data accesses can cause an unnecessary paging load on memory bound * processes. This optimization causes one-time-use metadata to be * reused more quickly. * * Normally athead is 0 resulting in LRU operation. athead is set * to 1 if we want this page to be 'as if it were placed in the cache', * except without unmapping it from the process address space. * * The page must be locked. */ static inline void _vm_page_deactivate(vm_page_t m, int athead) { struct vm_pagequeue *pq; int queue; vm_page_lock_assert(m, MA_OWNED); /* * Ignore if already inactive. */ if ((queue = m->queue) == PQ_INACTIVE) return; if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { if (queue != PQ_NONE) vm_page_dequeue(m); m->flags &= ~PG_WINATCFLS; pq = &vm_pagequeues[PQ_INACTIVE]; vm_pagequeue_lock(pq); m->queue = PQ_INACTIVE; if (athead) TAILQ_INSERT_HEAD(&pq->pq_pl, m, pageq); else TAILQ_INSERT_TAIL(&pq->pq_pl, m, pageq); cnt.v_inactive_count++; vm_pagequeue_unlock(pq); } } /* * Move the specified page to the inactive queue. * * The page must be locked. */ void vm_page_deactivate(vm_page_t m) { _vm_page_deactivate(m, 0); } /* * vm_page_try_to_cache: * * Returns 0 on failure, 1 on success */ int vm_page_try_to_cache(vm_page_t m) { vm_page_lock_assert(m, MA_OWNED); VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (m->dirty || m->hold_count || m->busy || m->wire_count || (m->oflags & (VPO_BUSY | VPO_UNMANAGED)) != 0) return (0); pmap_remove_all(m); if (m->dirty) return (0); vm_page_cache(m); return (1); } /* * vm_page_try_to_free() * * Attempt to free the page. If we cannot free it, we do nothing. * 1 is returned on success, 0 on failure. */ int vm_page_try_to_free(vm_page_t m) { vm_page_lock_assert(m, MA_OWNED); if (m->object != NULL) VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (m->dirty || m->hold_count || m->busy || m->wire_count || (m->oflags & (VPO_BUSY | VPO_UNMANAGED)) != 0) return (0); pmap_remove_all(m); if (m->dirty) return (0); vm_page_free(m); return (1); } /* * vm_page_cache * * Put the specified page onto the page cache queue (if appropriate). * * The object and page must be locked. */ void vm_page_cache(vm_page_t m) { vm_object_t object; int old_empty_cache; vm_page_lock_assert(m, MA_OWNED); object = m->object; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); if ((m->oflags & (VPO_UNMANAGED | VPO_BUSY)) || m->busy || m->hold_count || m->wire_count) panic("vm_page_cache: attempting to cache busy page"); KASSERT(!pmap_page_is_mapped(m), ("vm_page_cache: page %p is mapped", m)); KASSERT(m->dirty == 0, ("vm_page_cache: page %p is dirty", m)); if (m->valid == 0 || object->type == OBJT_DEFAULT || (object->type == OBJT_SWAP && !vm_pager_has_page(object, m->pindex, NULL, NULL))) { /* * Hypothesis: A cache-elgible page belonging to a * default object or swap object but without a backing * store must be zero filled. */ vm_page_free(m); return; } KASSERT((m->flags & PG_CACHED) == 0, ("vm_page_cache: page %p is already cached", m)); PCPU_INC(cnt.v_tcached); /* * Remove the page from the paging queues. */ vm_page_remque(m); vm_radix_remove(&object->rtree, m->pindex); TAILQ_REMOVE(&object->memq, m, listq); object->resident_page_count--; /* * Restore the default memory attribute to the page. */ if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); /* * Insert the page into the object's collection of cached pages * and the physical memory allocator's cache/free page queues. */ m->flags &= ~PG_ZERO; mtx_lock(&vm_page_queue_free_mtx); m->flags |= PG_CACHED; old_empty_cache = vm_object_cache_is_empty(object); cnt.v_cache_count++; if (vm_radix_insert(&object->cache, m->pindex, m) != 0) panic("vm_page_cache: vm_radix_insert failed"); #if VM_NRESERVLEVEL > 0 if (!vm_reserv_free_page(m)) { #else if (TRUE) { #endif vm_phys_set_pool(VM_FREEPOOL_CACHE, m, 0); vm_phys_free_pages(m, 0); } vm_page_free_wakeup(); mtx_unlock(&vm_page_queue_free_mtx); /* * Increment the vnode's hold count if this is the object's only * cached page. Decrement the vnode's hold count if this was * the object's only resident page. */ if (object->type == OBJT_VNODE) { if (old_empty_cache != 0 && object->resident_page_count != 0) vhold(object->handle); else if (old_empty_cache == 0 && object->resident_page_count == 0) vdrop(object->handle); } } /* * vm_page_dontneed * * Cache, deactivate, or do nothing as appropriate. This routine * is typically used by madvise() MADV_DONTNEED. * * Generally speaking we want to move the page into the cache so * it gets reused quickly. However, this can result in a silly syndrome * due to the page recycling too quickly. Small objects will not be * fully cached. On the otherhand, if we move the page to the inactive * queue we wind up with a problem whereby very large objects * unnecessarily blow away our inactive and cache queues. * * The solution is to move the pages based on a fixed weighting. We * either leave them alone, deactivate them, or move them to the cache, * where moving them to the cache has the highest weighting. * By forcing some pages into other queues we eventually force the * system to balance the queues, potentially recovering other unrelated * space from active. The idea is to not force this to happen too * often. * * The object and page must be locked. */ void vm_page_dontneed(vm_page_t m) { int dnw; int head; vm_page_lock_assert(m, MA_OWNED); VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); dnw = PCPU_GET(dnweight); PCPU_INC(dnweight); /* * Occasionally leave the page alone. */ if ((dnw & 0x01F0) == 0 || m->queue == PQ_INACTIVE) { if (m->act_count >= ACT_INIT) --m->act_count; return; } /* * Clear any references to the page. Otherwise, the page daemon will * immediately reactivate the page. * * Perform the pmap_clear_reference() first. Otherwise, a concurrent * pmap operation, such as pmap_remove(), could clear a reference in * the pmap and set PGA_REFERENCED on the page before the * pmap_clear_reference() had completed. Consequently, the page would * appear referenced based upon an old reference that occurred before * this function ran. */ pmap_clear_reference(m); vm_page_aflag_clear(m, PGA_REFERENCED); if (m->dirty == 0 && pmap_is_modified(m)) vm_page_dirty(m); if (m->dirty || (dnw & 0x0070) == 0) { /* * Deactivate the page 3 times out of 32. */ head = 0; } else { /* * Cache the page 28 times out of every 32. Note that * the page is deactivated instead of cached, but placed * at the head of the queue instead of the tail. */ head = 1; } _vm_page_deactivate(m, head); } /* * Grab a page, waiting until we are waken up due to the page * changing state. We keep on waiting, if the page continues * to be in the object. If the page doesn't exist, first allocate it * and then conditionally zero it. * * The caller must always specify the VM_ALLOC_RETRY flag. This is intended * to facilitate its eventual removal. * * This routine may sleep. * * The object must be locked on entry. The lock will, however, be released * and reacquired if the routine sleeps. */ vm_page_t vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) { vm_page_t m; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT((allocflags & VM_ALLOC_RETRY) != 0, ("vm_page_grab: VM_ALLOC_RETRY is required")); retrylookup: if ((m = vm_page_lookup(object, pindex)) != NULL) { if ((m->oflags & VPO_BUSY) != 0 || ((allocflags & VM_ALLOC_IGN_SBUSY) == 0 && m->busy != 0)) { /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ vm_page_aflag_set(m, PGA_REFERENCED); vm_page_sleep(m, "pgrbwt"); goto retrylookup; } else { if ((allocflags & VM_ALLOC_WIRED) != 0) { vm_page_lock(m); vm_page_wire(m); vm_page_unlock(m); } if ((allocflags & VM_ALLOC_NOBUSY) == 0) vm_page_busy(m); return (m); } } m = vm_page_alloc(object, pindex, allocflags & ~(VM_ALLOC_RETRY | VM_ALLOC_IGN_SBUSY)); if (m == NULL) { VM_OBJECT_UNLOCK(object); VM_WAIT; VM_OBJECT_LOCK(object); goto retrylookup; } else if (m->valid != 0) return (m); if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) pmap_zero_page(m); return (m); } /* * Mapping function for valid or dirty bits in a page. * * Inputs are required to range within a page. */ vm_page_bits_t vm_page_bits(int base, int size) { int first_bit; int last_bit; KASSERT( base + size <= PAGE_SIZE, ("vm_page_bits: illegal base/size %d/%d", base, size) ); if (size == 0) /* handle degenerate case */ return (0); first_bit = base >> DEV_BSHIFT; last_bit = (base + size - 1) >> DEV_BSHIFT; return (((vm_page_bits_t)2 << last_bit) - ((vm_page_bits_t)1 << first_bit)); } /* * vm_page_set_valid_range: * * Sets portions of a page valid. The arguments are expected * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive * of any partial chunks touched by the range. The invalid portion of * such chunks will be zeroed. * * (base + size) must be less then or equal to PAGE_SIZE. */ void vm_page_set_valid_range(vm_page_t m, int base, int size) { int endoff, frag; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (size == 0) /* handle degenerate case */ return; /* * If the base is not DEV_BSIZE aligned and the valid * bit is clear, we have to zero out a portion of the * first block. */ if ((frag = base & ~(DEV_BSIZE - 1)) != base && (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, frag, base - frag); /* * If the ending offset is not DEV_BSIZE aligned and the * valid bit is clear, we have to zero out a portion of * the last block. */ endoff = base + size; if ((frag = endoff & ~(DEV_BSIZE - 1)) != endoff && (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, endoff, DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); /* * Assert that no previously invalid block that is now being validated * is already dirty. */ KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, ("vm_page_set_valid_range: page %p is dirty", m)); /* * Set valid bits inclusive of any overlap. */ m->valid |= vm_page_bits(base, size); } /* * Clear the given bits from the specified page's dirty field. */ static __inline void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) { uintptr_t addr; #if PAGE_SIZE < 16384 int shift; #endif /* * If the object is locked and the page is neither VPO_BUSY nor * write mapped, then the page's dirty field cannot possibly be * set by a concurrent pmap operation. */ VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if ((m->oflags & VPO_BUSY) == 0 && !pmap_page_is_write_mapped(m)) m->dirty &= ~pagebits; else { /* * The pmap layer can call vm_page_dirty() without * holding a distinguished lock. The combination of * the object's lock and an atomic operation suffice * to guarantee consistency of the page dirty field. * * For PAGE_SIZE == 32768 case, compiler already * properly aligns the dirty field, so no forcible * alignment is needed. Only require existence of * atomic_clear_64 when page size is 32768. */ addr = (uintptr_t)&m->dirty; #if PAGE_SIZE == 32768 atomic_clear_64((uint64_t *)addr, pagebits); #elif PAGE_SIZE == 16384 atomic_clear_32((uint32_t *)addr, pagebits); #else /* PAGE_SIZE <= 8192 */ /* * Use a trick to perform a 32-bit atomic on the * containing aligned word, to not depend on the existence * of atomic_clear_{8, 16}. */ shift = addr & (sizeof(uint32_t) - 1); #if BYTE_ORDER == BIG_ENDIAN shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY; #else shift *= NBBY; #endif addr &= ~(sizeof(uint32_t) - 1); atomic_clear_32((uint32_t *)addr, pagebits << shift); #endif /* PAGE_SIZE */ } } /* * vm_page_set_validclean: * * Sets portions of a page valid and clean. The arguments are expected * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive * of any partial chunks touched by the range. The invalid portion of * such chunks will be zero'd. * * (base + size) must be less then or equal to PAGE_SIZE. */ void vm_page_set_validclean(vm_page_t m, int base, int size) { vm_page_bits_t oldvalid, pagebits; int endoff, frag; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (size == 0) /* handle degenerate case */ return; /* * If the base is not DEV_BSIZE aligned and the valid * bit is clear, we have to zero out a portion of the * first block. */ if ((frag = base & ~(DEV_BSIZE - 1)) != base && (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, frag, base - frag); /* * If the ending offset is not DEV_BSIZE aligned and the * valid bit is clear, we have to zero out a portion of * the last block. */ endoff = base + size; if ((frag = endoff & ~(DEV_BSIZE - 1)) != endoff && (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) pmap_zero_page_area(m, endoff, DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); /* * Set valid, clear dirty bits. If validating the entire * page we can safely clear the pmap modify bit. We also * use this opportunity to clear the VPO_NOSYNC flag. If a process * takes a write fault on a MAP_NOSYNC memory area the flag will * be set again. * * We set valid bits inclusive of any overlap, but we can only * clear dirty bits for DEV_BSIZE chunks that are fully within * the range. */ oldvalid = m->valid; pagebits = vm_page_bits(base, size); m->valid |= pagebits; #if 0 /* NOT YET */ if ((frag = base & (DEV_BSIZE - 1)) != 0) { frag = DEV_BSIZE - frag; base += frag; size -= frag; if (size < 0) size = 0; } pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); #endif if (base == 0 && size == PAGE_SIZE) { /* * The page can only be modified within the pmap if it is * mapped, and it can only be mapped if it was previously * fully valid. */ if (oldvalid == VM_PAGE_BITS_ALL) /* * Perform the pmap_clear_modify() first. Otherwise, * a concurrent pmap operation, such as * pmap_protect(), could clear a modification in the * pmap and set the dirty field on the page before * pmap_clear_modify() had begun and after the dirty * field was cleared here. */ pmap_clear_modify(m); m->dirty = 0; m->oflags &= ~VPO_NOSYNC; } else if (oldvalid != VM_PAGE_BITS_ALL) m->dirty &= ~pagebits; else vm_page_clear_dirty_mask(m, pagebits); } void vm_page_clear_dirty(vm_page_t m, int base, int size) { vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); } /* * vm_page_set_invalid: * * Invalidates DEV_BSIZE'd chunks within a page. Both the * valid and dirty bits for the effected areas are cleared. */ void vm_page_set_invalid(vm_page_t m, int base, int size) { vm_page_bits_t bits; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); KASSERT((m->oflags & VPO_BUSY) == 0, ("vm_page_set_invalid: page %p is busy", m)); bits = vm_page_bits(base, size); if (m->valid == VM_PAGE_BITS_ALL && bits != 0) pmap_remove_all(m); KASSERT(!pmap_page_is_mapped(m), ("vm_page_set_invalid: page %p is mapped", m)); m->valid &= ~bits; m->dirty &= ~bits; } /* * vm_page_zero_invalid() * * The kernel assumes that the invalid portions of a page contain * garbage, but such pages can be mapped into memory by user code. * When this occurs, we must zero out the non-valid portions of the * page so user code sees what it expects. * * Pages are most often semi-valid when the end of a file is mapped * into memory and the file's size is not page aligned. */ void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) { int b; int i; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); /* * Scan the valid bits looking for invalid sections that * must be zerod. Invalid sub-DEV_BSIZE'd areas ( where the * valid bit may be set ) have already been zerod by * vm_page_set_validclean(). */ for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { if (i == (PAGE_SIZE / DEV_BSIZE) || (m->valid & ((vm_page_bits_t)1 << i))) { if (i > b) { pmap_zero_page_area(m, b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); } b = i + 1; } } /* * setvalid is TRUE when we can safely set the zero'd areas * as being valid. We can do this if there are no cache consistancy * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. */ if (setvalid) m->valid = VM_PAGE_BITS_ALL; } /* * vm_page_is_valid: * * Is (partial) page valid? Note that the case where size == 0 * will return FALSE in the degenerate case where the page is * entirely invalid, and TRUE otherwise. */ int vm_page_is_valid(vm_page_t m, int base, int size) { vm_page_bits_t bits; VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); bits = vm_page_bits(base, size); if (m->valid && ((m->valid & bits) == bits)) return 1; else return 0; } /* * Set the page's dirty bits if the page is modified. */ void vm_page_test_dirty(vm_page_t m) { VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) vm_page_dirty(m); } void vm_page_lock_KBI(vm_page_t m, const char *file, int line) { mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); } void vm_page_unlock_KBI(vm_page_t m, const char *file, int line) { mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); } int vm_page_trylock_KBI(vm_page_t m, const char *file, int line) { return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); } #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) { mtx_assert_(vm_page_lockptr(m), a, file, line); } #endif int so_zerocp_fullpage = 0; /* * Replace the given page with a copy. The copied page assumes * the portion of the given page's "wire_count" that is not the * responsibility of this copy-on-write mechanism. * * The object containing the given page must have a non-zero * paging-in-progress count and be locked. */ void vm_page_cowfault(vm_page_t m) { vm_page_t mnew; vm_object_t object; vm_pindex_t pindex; vm_page_lock_assert(m, MA_OWNED); object = m->object; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); KASSERT(object->paging_in_progress != 0, ("vm_page_cowfault: object %p's paging-in-progress count is zero.", object)); pindex = m->pindex; retry_alloc: pmap_remove_all(m); vm_page_remove(m); mnew = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL | VM_ALLOC_NOBUSY); if (mnew == NULL) { vm_page_insert(m, object, pindex); vm_page_unlock(m); VM_OBJECT_UNLOCK(object); VM_WAIT; VM_OBJECT_LOCK(object); if (m == vm_page_lookup(object, pindex)) { vm_page_lock(m); goto retry_alloc; } else { /* * Page disappeared during the wait. */ return; } } if (m->cow == 0) { /* * check to see if we raced with an xmit complete when * waiting to allocate a page. If so, put things back * the way they were */ vm_page_unlock(m); vm_page_lock(mnew); vm_page_free(mnew); vm_page_unlock(mnew); vm_page_insert(m, object, pindex); } else { /* clear COW & copy page */ if (!so_zerocp_fullpage) pmap_copy_page(m, mnew); mnew->valid = VM_PAGE_BITS_ALL; vm_page_dirty(mnew); mnew->wire_count = m->wire_count - m->cow; m->wire_count = m->cow; vm_page_unlock(m); } } void vm_page_cowclear(vm_page_t m) { vm_page_lock_assert(m, MA_OWNED); if (m->cow) { m->cow--; /* * let vm_fault add back write permission lazily */ } /* * sf_buf_free() will free the page, so we needn't do it here */ } int vm_page_cowsetup(vm_page_t m) { vm_page_lock_assert(m, MA_OWNED); if ((m->flags & PG_FICTITIOUS) != 0 || (m->oflags & VPO_UNMANAGED) != 0 || m->cow == USHRT_MAX - 1 || !VM_OBJECT_TRYLOCK(m->object)) return (EBUSY); m->cow++; pmap_remove_write(m); VM_OBJECT_UNLOCK(m->object); return (0); } #ifdef INVARIANTS void vm_page_object_lock_assert(vm_page_t m) { /* * Certain of the page's fields may only be modified by the * holder of the containing object's lock or the setter of the * page's VPO_BUSY flag. Unfortunately, the setter of the * VPO_BUSY flag is not recorded, and thus cannot be checked * here. */ if (m->object != NULL && (m->oflags & VPO_BUSY) == 0) VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); } #endif #include "opt_ddb.h" #ifdef DDB #include #include DB_SHOW_COMMAND(page, vm_page_print_page_info) { db_printf("cnt.v_free_count: %d\n", cnt.v_free_count); db_printf("cnt.v_cache_count: %d\n", cnt.v_cache_count); db_printf("cnt.v_inactive_count: %d\n", cnt.v_inactive_count); db_printf("cnt.v_active_count: %d\n", cnt.v_active_count); db_printf("cnt.v_wire_count: %d\n", cnt.v_wire_count); db_printf("cnt.v_free_reserved: %d\n", cnt.v_free_reserved); db_printf("cnt.v_free_min: %d\n", cnt.v_free_min); db_printf("cnt.v_free_target: %d\n", cnt.v_free_target); db_printf("cnt.v_cache_min: %d\n", cnt.v_cache_min); db_printf("cnt.v_inactive_target: %d\n", cnt.v_inactive_target); } DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) { db_printf("PQ_FREE:"); db_printf(" %d", cnt.v_free_count); db_printf("\n"); db_printf("PQ_CACHE:"); db_printf(" %d", cnt.v_cache_count); db_printf("\n"); db_printf("PQ_ACTIVE: %d, PQ_INACTIVE: %d\n", *vm_pagequeues[PQ_ACTIVE].pq_cnt, *vm_pagequeues[PQ_INACTIVE].pq_cnt); } #endif /* DDB */ Index: user/attilio/vmc-playground/sys/vm/vnode_pager.c =================================================================== --- user/attilio/vmc-playground/sys/vm/vnode_pager.c (revision 246331) +++ user/attilio/vmc-playground/sys/vm/vnode_pager.c (revision 246332) @@ -1,1291 +1,1290 @@ /*- * Copyright (c) 1990 University of Utah. * Copyright (c) 1991 The Regents of the University of California. * All rights reserved. * Copyright (c) 1993, 1994 John S. Dyson * Copyright (c) 1995, David Greenman * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vnode_pager.c 7.5 (Berkeley) 4/20/91 */ /* * Page to/from files (vnodes). */ /* * TODO: * Implement VOP_GETPAGES/PUTPAGES interface for filesystems. Will * greatly re-simplify the vnode_pager. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static int vnode_pager_addr(struct vnode *vp, vm_ooffset_t address, daddr_t *rtaddress, int *run); static int vnode_pager_input_smlfs(vm_object_t object, vm_page_t m); static int vnode_pager_input_old(vm_object_t object, vm_page_t m); static void vnode_pager_dealloc(vm_object_t); static int vnode_pager_getpages(vm_object_t, vm_page_t *, int, int); static void vnode_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); static boolean_t vnode_pager_haspage(vm_object_t, vm_pindex_t, int *, int *); static vm_object_t vnode_pager_alloc(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *cred); struct pagerops vnodepagerops = { .pgo_alloc = vnode_pager_alloc, .pgo_dealloc = vnode_pager_dealloc, .pgo_getpages = vnode_pager_getpages, .pgo_putpages = vnode_pager_putpages, .pgo_haspage = vnode_pager_haspage, }; int vnode_pbuf_freecnt; /* Create the VM system backing object for this vnode */ int vnode_create_vobject(struct vnode *vp, off_t isize, struct thread *td) { vm_object_t object; vm_ooffset_t size = isize; struct vattr va; if (!vn_isdisk(vp, NULL) && vn_canvmio(vp) == FALSE) return (0); while ((object = vp->v_object) != NULL) { VM_OBJECT_LOCK(object); if (!(object->flags & OBJ_DEAD)) { VM_OBJECT_UNLOCK(object); return (0); } VOP_UNLOCK(vp, 0); vm_object_set_flag(object, OBJ_DISCONNECTWNT); msleep(object, VM_OBJECT_MTX(object), PDROP | PVM, "vodead", 0); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); } if (size == 0) { if (vn_isdisk(vp, NULL)) { size = IDX_TO_OFF(INT_MAX); } else { if (VOP_GETATTR(vp, &va, td->td_ucred)) return (0); size = va.va_size; } } object = vnode_pager_alloc(vp, size, 0, 0, td->td_ucred); /* * Dereference the reference we just created. This assumes * that the object is associated with the vp. */ VM_OBJECT_LOCK(object); object->ref_count--; VM_OBJECT_UNLOCK(object); vrele(vp); KASSERT(vp->v_object != NULL, ("vnode_create_vobject: NULL object")); return (0); } void vnode_destroy_vobject(struct vnode *vp) { struct vm_object *obj; obj = vp->v_object; if (obj == NULL) return; ASSERT_VOP_ELOCKED(vp, "vnode_destroy_vobject"); VM_OBJECT_LOCK(obj); if (obj->ref_count == 0) { /* * vclean() may be called twice. The first time * removes the primary reference to the object, * the second time goes one further and is a * special-case to terminate the object. * * don't double-terminate the object */ if ((obj->flags & OBJ_DEAD) == 0) vm_object_terminate(obj); else VM_OBJECT_UNLOCK(obj); } else { /* * Woe to the process that tries to page now :-). */ vm_pager_deallocate(obj); VM_OBJECT_UNLOCK(obj); } vp->v_object = NULL; } /* * Allocate (or lookup) pager for a vnode. * Handle is a vnode pointer. * * MPSAFE */ vm_object_t vnode_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t offset, struct ucred *cred) { vm_object_t object; struct vnode *vp; /* * Pageout to vnode, no can do yet. */ if (handle == NULL) return (NULL); vp = (struct vnode *) handle; /* * If the object is being terminated, wait for it to * go away. */ retry: while ((object = vp->v_object) != NULL) { VM_OBJECT_LOCK(object); if ((object->flags & OBJ_DEAD) == 0) break; vm_object_set_flag(object, OBJ_DISCONNECTWNT); msleep(object, VM_OBJECT_MTX(object), PDROP | PVM, "vadead", 0); } if (vp->v_usecount == 0) panic("vnode_pager_alloc: no vnode reference"); if (object == NULL) { /* * Add an object of the appropriate size */ object = vm_object_allocate(OBJT_VNODE, OFF_TO_IDX(round_page(size))); object->un_pager.vnp.vnp_size = size; object->un_pager.vnp.writemappings = 0; object->handle = handle; VI_LOCK(vp); if (vp->v_object != NULL) { /* * Object has been created while we were sleeping */ VI_UNLOCK(vp); vm_object_destroy(object); goto retry; } vp->v_object = object; VI_UNLOCK(vp); } else { object->ref_count++; VM_OBJECT_UNLOCK(object); } vref(vp); return (object); } /* * The object must be locked. */ static void vnode_pager_dealloc(object) vm_object_t object; { struct vnode *vp; int refs; vp = object->handle; if (vp == NULL) panic("vnode_pager_dealloc: pager already dealloced"); VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); vm_object_pip_wait(object, "vnpdea"); refs = object->ref_count; object->handle = NULL; object->type = OBJT_DEAD; if (object->flags & OBJ_DISCONNECTWNT) { vm_object_clear_flag(object, OBJ_DISCONNECTWNT); wakeup(object); } ASSERT_VOP_ELOCKED(vp, "vnode_pager_dealloc"); if (object->un_pager.vnp.writemappings > 0) { object->un_pager.vnp.writemappings = 0; VOP_ADD_WRITECOUNT(vp, -1); CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d", __func__, vp, vp->v_writecount); } vp->v_object = NULL; VOP_UNSET_TEXT(vp); VM_OBJECT_UNLOCK(object); while (refs-- > 0) vunref(vp); VM_OBJECT_LOCK(object); } static boolean_t vnode_pager_haspage(object, pindex, before, after) vm_object_t object; vm_pindex_t pindex; int *before; int *after; { struct vnode *vp = object->handle; daddr_t bn; int err; daddr_t reqblock; int poff; int bsize; int pagesperblock, blocksperpage; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); /* * If no vp or vp is doomed or marked transparent to VM, we do not * have the page. */ if (vp == NULL || vp->v_iflag & VI_DOOMED) return FALSE; /* * If the offset is beyond end of file we do * not have the page. */ if (IDX_TO_OFF(pindex) >= object->un_pager.vnp.vnp_size) return FALSE; bsize = vp->v_mount->mnt_stat.f_iosize; pagesperblock = bsize / PAGE_SIZE; blocksperpage = 0; if (pagesperblock > 0) { reqblock = pindex / pagesperblock; } else { blocksperpage = (PAGE_SIZE / bsize); reqblock = pindex * blocksperpage; } VM_OBJECT_UNLOCK(object); err = VOP_BMAP(vp, reqblock, NULL, &bn, after, before); VM_OBJECT_LOCK(object); if (err) return TRUE; if (bn == -1) return FALSE; if (pagesperblock > 0) { poff = pindex - (reqblock * pagesperblock); if (before) { *before *= pagesperblock; *before += poff; } if (after) { int numafter; *after *= pagesperblock; numafter = pagesperblock - (poff + 1); if (IDX_TO_OFF(pindex + numafter) > object->un_pager.vnp.vnp_size) { numafter = OFF_TO_IDX(object->un_pager.vnp.vnp_size) - pindex; } *after += numafter; } } else { if (before) { *before /= blocksperpage; } if (after) { *after /= blocksperpage; } } return TRUE; } /* * Lets the VM system know about a change in size for a file. * We adjust our own internal size and flush any cached pages in * the associated object that are affected by the size change. * * Note: this routine may be invoked as a result of a pager put * operation (possibly at object termination time), so we must be careful. */ void vnode_pager_setsize(vp, nsize) struct vnode *vp; vm_ooffset_t nsize; { vm_object_t object; struct vnode *drop; vm_page_t m; vm_pindex_t nobjsize; if ((object = vp->v_object) == NULL) return; /* ASSERT_VOP_ELOCKED(vp, "vnode_pager_setsize and not locked vnode"); */ VM_OBJECT_LOCK(object); if (nsize == object->un_pager.vnp.vnp_size) { /* * Hasn't changed size */ VM_OBJECT_UNLOCK(object); return; } nobjsize = OFF_TO_IDX(nsize + PAGE_MASK); if (nsize < object->un_pager.vnp.vnp_size) { /* * File has shrunk. Toss any cached pages beyond the new EOF. */ if (nobjsize < object->size) vm_object_page_remove(object, nobjsize, object->size, 0); /* * this gets rid of garbage at the end of a page that is now * only partially backed by the vnode. * * XXX for some reason (I don't know yet), if we take a * completely invalid page and mark it partially valid * it can screw up NFS reads, so we don't allow the case. */ - if ((nsize & PAGE_MASK) && (m = vm_radix_lookup(&object->rtree, - OFF_TO_IDX(nsize))) != NULL && m->valid != 0) { + if ((nsize & PAGE_MASK) && + (m = vm_page_lookup(object, OFF_TO_IDX(nsize))) != NULL && + m->valid != 0) { int base = (int)nsize & PAGE_MASK; int size = PAGE_SIZE - base; - - MPASS(m->object == object); /* * Clear out partial-page garbage in case * the page has been mapped. */ pmap_zero_page_area(m, base, size); /* * Update the valid bits to reflect the blocks that * have been zeroed. Some of these valid bits may * have already been set. */ vm_page_set_valid_range(m, base, size); /* * Round "base" to the next block boundary so that the * dirty bit for a partially zeroed block is not * cleared. */ base = roundup2(base, DEV_BSIZE); /* * Clear out partial-page dirty bits. * * note that we do not clear out the valid * bits. This would prevent bogus_page * replacement from working properly. */ vm_page_clear_dirty(m, base, PAGE_SIZE - base); } else if ((nsize & PAGE_MASK) && (m = vm_page_is_cached(object, OFF_TO_IDX(nsize))) != NULL) { drop = NULL; mtx_lock(&vm_page_queue_free_mtx); if (m->object == object) { /* * Eliminate any cached page as we would have * to do too much work to save it. */ vm_page_cache_free(m); if (vm_object_cache_is_empty(object)) drop = vp; } mtx_unlock(&vm_page_queue_free_mtx); if (drop) vdrop(drop); } } object->un_pager.vnp.vnp_size = nsize; object->size = nobjsize; VM_OBJECT_UNLOCK(object); } /* * calculate the linear (byte) disk address of specified virtual * file address */ static int vnode_pager_addr(struct vnode *vp, vm_ooffset_t address, daddr_t *rtaddress, int *run) { int bsize; int err; daddr_t vblock; daddr_t voffset; if (address < 0) return -1; if (vp->v_iflag & VI_DOOMED) return -1; bsize = vp->v_mount->mnt_stat.f_iosize; vblock = address / bsize; voffset = address % bsize; err = VOP_BMAP(vp, vblock, NULL, rtaddress, run, NULL); if (err == 0) { if (*rtaddress != -1) *rtaddress += voffset / DEV_BSIZE; if (run) { *run += 1; *run *= bsize/PAGE_SIZE; *run -= voffset/PAGE_SIZE; } } return (err); } /* * small block filesystem vnode pager input */ static int vnode_pager_input_smlfs(object, m) vm_object_t object; vm_page_t m; { struct vnode *vp; struct bufobj *bo; struct buf *bp; struct sf_buf *sf; daddr_t fileaddr; vm_offset_t bsize; vm_page_bits_t bits; int error, i; error = 0; vp = object->handle; if (vp->v_iflag & VI_DOOMED) return VM_PAGER_BAD; bsize = vp->v_mount->mnt_stat.f_iosize; VOP_BMAP(vp, 0, &bo, 0, NULL, NULL); sf = sf_buf_alloc(m, 0); for (i = 0; i < PAGE_SIZE / bsize; i++) { vm_ooffset_t address; bits = vm_page_bits(i * bsize, bsize); if (m->valid & bits) continue; address = IDX_TO_OFF(m->pindex) + i * bsize; if (address >= object->un_pager.vnp.vnp_size) { fileaddr = -1; } else { error = vnode_pager_addr(vp, address, &fileaddr, NULL); if (error) break; } if (fileaddr != -1) { bp = getpbuf(&vnode_pbuf_freecnt); /* build a minimal buffer header */ bp->b_iocmd = BIO_READ; bp->b_iodone = bdone; KASSERT(bp->b_rcred == NOCRED, ("leaking read ucred")); KASSERT(bp->b_wcred == NOCRED, ("leaking write ucred")); bp->b_rcred = crhold(curthread->td_ucred); bp->b_wcred = crhold(curthread->td_ucred); bp->b_data = (caddr_t)sf_buf_kva(sf) + i * bsize; bp->b_blkno = fileaddr; pbgetbo(bo, bp); bp->b_vp = vp; bp->b_bcount = bsize; bp->b_bufsize = bsize; bp->b_runningbufspace = bp->b_bufsize; atomic_add_long(&runningbufspace, bp->b_runningbufspace); /* do the input */ bp->b_iooffset = dbtob(bp->b_blkno); bstrategy(bp); bwait(bp, PVM, "vnsrd"); if ((bp->b_ioflags & BIO_ERROR) != 0) error = EIO; /* * free the buffer header back to the swap buffer pool */ bp->b_vp = NULL; pbrelbo(bp); relpbuf(bp, &vnode_pbuf_freecnt); if (error) break; } else bzero((caddr_t)sf_buf_kva(sf) + i * bsize, bsize); KASSERT((m->dirty & bits) == 0, ("vnode_pager_input_smlfs: page %p is dirty", m)); VM_OBJECT_LOCK(object); m->valid |= bits; VM_OBJECT_UNLOCK(object); } sf_buf_free(sf); if (error) { return VM_PAGER_ERROR; } return VM_PAGER_OK; } /* * old style vnode pager input routine */ static int vnode_pager_input_old(object, m) vm_object_t object; vm_page_t m; { struct uio auio; struct iovec aiov; int error; int size; struct sf_buf *sf; struct vnode *vp; VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); error = 0; /* * Return failure if beyond current EOF */ if (IDX_TO_OFF(m->pindex) >= object->un_pager.vnp.vnp_size) { return VM_PAGER_BAD; } else { size = PAGE_SIZE; if (IDX_TO_OFF(m->pindex) + size > object->un_pager.vnp.vnp_size) size = object->un_pager.vnp.vnp_size - IDX_TO_OFF(m->pindex); vp = object->handle; VM_OBJECT_UNLOCK(object); /* * Allocate a kernel virtual address and initialize so that * we can use VOP_READ/WRITE routines. */ sf = sf_buf_alloc(m, 0); aiov.iov_base = (caddr_t)sf_buf_kva(sf); aiov.iov_len = size; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = IDX_TO_OFF(m->pindex); auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_READ; auio.uio_resid = size; auio.uio_td = curthread; error = VOP_READ(vp, &auio, 0, curthread->td_ucred); if (!error) { int count = size - auio.uio_resid; if (count == 0) error = EINVAL; else if (count != PAGE_SIZE) bzero((caddr_t)sf_buf_kva(sf) + count, PAGE_SIZE - count); } sf_buf_free(sf); VM_OBJECT_LOCK(object); } KASSERT(m->dirty == 0, ("vnode_pager_input_old: page %p is dirty", m)); if (!error) m->valid = VM_PAGE_BITS_ALL; return error ? VM_PAGER_ERROR : VM_PAGER_OK; } /* * generic vnode pager input routine */ /* * Local media VFS's that do not implement their own VOP_GETPAGES * should have their VOP_GETPAGES call to vnode_pager_generic_getpages() * to implement the previous behaviour. * * All other FS's should use the bypass to get to the local media * backing vp's VOP_GETPAGES. */ static int vnode_pager_getpages(object, m, count, reqpage) vm_object_t object; vm_page_t *m; int count; int reqpage; { int rtval; struct vnode *vp; int bytes = count * PAGE_SIZE; vp = object->handle; VM_OBJECT_UNLOCK(object); rtval = VOP_GETPAGES(vp, m, bytes, reqpage, 0); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: FS getpages not implemented\n")); VM_OBJECT_LOCK(object); return rtval; } /* * This is now called from local media FS's to operate against their * own vnodes if they fail to implement VOP_GETPAGES. */ int vnode_pager_generic_getpages(vp, m, bytecount, reqpage) struct vnode *vp; vm_page_t *m; int bytecount; int reqpage; { vm_object_t object; vm_offset_t kva; off_t foff, tfoff, nextoff; int i, j, size, bsize, first; daddr_t firstaddr, reqblock; struct bufobj *bo; int runpg; int runend; struct buf *bp; int count; int error; object = vp->v_object; count = bytecount / PAGE_SIZE; KASSERT(vp->v_type != VCHR && vp->v_type != VBLK, ("vnode_pager_generic_getpages does not support devices")); if (vp->v_iflag & VI_DOOMED) return VM_PAGER_BAD; bsize = vp->v_mount->mnt_stat.f_iosize; /* get the UNDERLYING device for the file with VOP_BMAP() */ /* * originally, we did not check for an error return value -- assuming * an fs always has a bmap entry point -- that assumption is wrong!!! */ foff = IDX_TO_OFF(m[reqpage]->pindex); /* * if we can't bmap, use old VOP code */ error = VOP_BMAP(vp, foff / bsize, &bo, &reqblock, NULL, NULL); if (error == EOPNOTSUPP) { VM_OBJECT_LOCK(object); for (i = 0; i < count; i++) if (i != reqpage) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } PCPU_INC(cnt.v_vnodein); PCPU_INC(cnt.v_vnodepgsin); error = vnode_pager_input_old(object, m[reqpage]); VM_OBJECT_UNLOCK(object); return (error); } else if (error != 0) { VM_OBJECT_LOCK(object); for (i = 0; i < count; i++) if (i != reqpage) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } VM_OBJECT_UNLOCK(object); return (VM_PAGER_ERROR); /* * if the blocksize is smaller than a page size, then use * special small filesystem code. NFS sometimes has a small * blocksize, but it can handle large reads itself. */ } else if ((PAGE_SIZE / bsize) > 1 && (vp->v_mount->mnt_stat.f_type != nfs_mount_type)) { VM_OBJECT_LOCK(object); for (i = 0; i < count; i++) if (i != reqpage) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } VM_OBJECT_UNLOCK(object); PCPU_INC(cnt.v_vnodein); PCPU_INC(cnt.v_vnodepgsin); return vnode_pager_input_smlfs(object, m[reqpage]); } /* * If we have a completely valid page available to us, we can * clean up and return. Otherwise we have to re-read the * media. */ VM_OBJECT_LOCK(object); if (m[reqpage]->valid == VM_PAGE_BITS_ALL) { for (i = 0; i < count; i++) if (i != reqpage) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } VM_OBJECT_UNLOCK(object); return VM_PAGER_OK; } else if (reqblock == -1) { pmap_zero_page(m[reqpage]); KASSERT(m[reqpage]->dirty == 0, ("vnode_pager_generic_getpages: page %p is dirty", m)); m[reqpage]->valid = VM_PAGE_BITS_ALL; for (i = 0; i < count; i++) if (i != reqpage) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } VM_OBJECT_UNLOCK(object); return (VM_PAGER_OK); } m[reqpage]->valid = 0; VM_OBJECT_UNLOCK(object); /* * here on direct device I/O */ firstaddr = -1; /* * calculate the run that includes the required page */ for (first = 0, i = 0; i < count; i = runend) { if (vnode_pager_addr(vp, IDX_TO_OFF(m[i]->pindex), &firstaddr, &runpg) != 0) { VM_OBJECT_LOCK(object); for (; i < count; i++) if (i != reqpage) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } VM_OBJECT_UNLOCK(object); return (VM_PAGER_ERROR); } if (firstaddr == -1) { VM_OBJECT_LOCK(object); if (i == reqpage && foff < object->un_pager.vnp.vnp_size) { panic("vnode_pager_getpages: unexpected missing page: firstaddr: %jd, foff: 0x%jx%08jx, vnp_size: 0x%jx%08jx", (intmax_t)firstaddr, (uintmax_t)(foff >> 32), (uintmax_t)foff, (uintmax_t) (object->un_pager.vnp.vnp_size >> 32), (uintmax_t)object->un_pager.vnp.vnp_size); } vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); VM_OBJECT_UNLOCK(object); runend = i + 1; first = runend; continue; } runend = i + runpg; if (runend <= reqpage) { VM_OBJECT_LOCK(object); for (j = i; j < runend; j++) { vm_page_lock(m[j]); vm_page_free(m[j]); vm_page_unlock(m[j]); } VM_OBJECT_UNLOCK(object); } else { if (runpg < (count - first)) { VM_OBJECT_LOCK(object); for (i = first + runpg; i < count; i++) { vm_page_lock(m[i]); vm_page_free(m[i]); vm_page_unlock(m[i]); } VM_OBJECT_UNLOCK(object); count = first + runpg; } break; } first = runend; } /* * the first and last page have been calculated now, move input pages * to be zero based... */ if (first != 0) { m += first; count -= first; reqpage -= first; } /* * calculate the file virtual address for the transfer */ foff = IDX_TO_OFF(m[0]->pindex); /* * calculate the size of the transfer */ size = count * PAGE_SIZE; KASSERT(count > 0, ("zero count")); if ((foff + size) > object->un_pager.vnp.vnp_size) size = object->un_pager.vnp.vnp_size - foff; KASSERT(size > 0, ("zero size")); /* * round up physical size for real devices. */ if (1) { int secmask = bo->bo_bsize - 1; KASSERT(secmask < PAGE_SIZE && secmask > 0, ("vnode_pager_generic_getpages: sector size %d too large", secmask + 1)); size = (size + secmask) & ~secmask; } bp = getpbuf(&vnode_pbuf_freecnt); kva = (vm_offset_t) bp->b_data; /* * and map the pages to be read into the kva */ pmap_qenter(kva, m, count); /* build a minimal buffer header */ bp->b_iocmd = BIO_READ; bp->b_iodone = bdone; KASSERT(bp->b_rcred == NOCRED, ("leaking read ucred")); KASSERT(bp->b_wcred == NOCRED, ("leaking write ucred")); bp->b_rcred = crhold(curthread->td_ucred); bp->b_wcred = crhold(curthread->td_ucred); bp->b_blkno = firstaddr; pbgetbo(bo, bp); bp->b_vp = vp; bp->b_bcount = size; bp->b_bufsize = size; bp->b_runningbufspace = bp->b_bufsize; atomic_add_long(&runningbufspace, bp->b_runningbufspace); PCPU_INC(cnt.v_vnodein); PCPU_ADD(cnt.v_vnodepgsin, count); /* do the input */ bp->b_iooffset = dbtob(bp->b_blkno); bstrategy(bp); bwait(bp, PVM, "vnread"); if ((bp->b_ioflags & BIO_ERROR) != 0) error = EIO; if (!error) { if (size != count * PAGE_SIZE) bzero((caddr_t) kva + size, PAGE_SIZE * count - size); } pmap_qremove(kva, count); /* * free the buffer header back to the swap buffer pool */ bp->b_vp = NULL; pbrelbo(bp); relpbuf(bp, &vnode_pbuf_freecnt); VM_OBJECT_LOCK(object); for (i = 0, tfoff = foff; i < count; i++, tfoff = nextoff) { vm_page_t mt; nextoff = tfoff + PAGE_SIZE; mt = m[i]; if (nextoff <= object->un_pager.vnp.vnp_size) { /* * Read filled up entire page. */ mt->valid = VM_PAGE_BITS_ALL; KASSERT(mt->dirty == 0, ("vnode_pager_generic_getpages: page %p is dirty", mt)); KASSERT(!pmap_page_is_mapped(mt), ("vnode_pager_generic_getpages: page %p is mapped", mt)); } else { /* * Read did not fill up entire page. * * Currently we do not set the entire page valid, * we just try to clear the piece that we couldn't * read. */ vm_page_set_valid_range(mt, 0, object->un_pager.vnp.vnp_size - tfoff); KASSERT((mt->dirty & vm_page_bits(0, object->un_pager.vnp.vnp_size - tfoff)) == 0, ("vnode_pager_generic_getpages: page %p is dirty", mt)); } if (i != reqpage) vm_page_readahead_finish(mt); } VM_OBJECT_UNLOCK(object); if (error) { printf("vnode_pager_getpages: I/O read error\n"); } return (error ? VM_PAGER_ERROR : VM_PAGER_OK); } /* * EOPNOTSUPP is no longer legal. For local media VFS's that do not * implement their own VOP_PUTPAGES, their VOP_PUTPAGES should call to * vnode_pager_generic_putpages() to implement the previous behaviour. * * All other FS's should use the bypass to get to the local media * backing vp's VOP_PUTPAGES. */ static void vnode_pager_putpages(object, m, count, sync, rtvals) vm_object_t object; vm_page_t *m; int count; boolean_t sync; int *rtvals; { int rtval; struct vnode *vp; int bytes = count * PAGE_SIZE; /* * Force synchronous operation if we are extremely low on memory * to prevent a low-memory deadlock. VOP operations often need to * allocate more memory to initiate the I/O ( i.e. do a BMAP * operation ). The swapper handles the case by limiting the amount * of asynchronous I/O, but that sort of solution doesn't scale well * for the vnode pager without a lot of work. * * Also, the backing vnode's iodone routine may not wake the pageout * daemon up. This should be probably be addressed XXX. */ if ((cnt.v_free_count + cnt.v_cache_count) < cnt.v_pageout_free_min) sync |= OBJPC_SYNC; /* * Call device-specific putpages function */ vp = object->handle; VM_OBJECT_UNLOCK(object); rtval = VOP_PUTPAGES(vp, m, bytes, sync, rtvals, 0); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: stale FS putpages\n")); VM_OBJECT_LOCK(object); } /* * This is now called from local media FS's to operate against their * own vnodes if they fail to implement VOP_PUTPAGES. * * This is typically called indirectly via the pageout daemon and * clustering has already typically occured, so in general we ask the * underlying filesystem to write the data out asynchronously rather * then delayed. */ int vnode_pager_generic_putpages(struct vnode *vp, vm_page_t *ma, int bytecount, int flags, int *rtvals) { int i; vm_object_t object; vm_page_t m; int count; int maxsize, ncount; vm_ooffset_t poffset; struct uio auio; struct iovec aiov; int error; int ioflags; int ppscheck = 0; static struct timeval lastfail; static int curfail; object = vp->v_object; count = bytecount / PAGE_SIZE; for (i = 0; i < count; i++) rtvals[i] = VM_PAGER_ERROR; if ((int64_t)ma[0]->pindex < 0) { printf("vnode_pager_putpages: attempt to write meta-data!!! -- 0x%lx(%lx)\n", (long)ma[0]->pindex, (u_long)ma[0]->dirty); rtvals[0] = VM_PAGER_BAD; return VM_PAGER_BAD; } maxsize = count * PAGE_SIZE; ncount = count; poffset = IDX_TO_OFF(ma[0]->pindex); /* * If the page-aligned write is larger then the actual file we * have to invalidate pages occuring beyond the file EOF. However, * there is an edge case where a file may not be page-aligned where * the last page is partially invalid. In this case the filesystem * may not properly clear the dirty bits for the entire page (which * could be VM_PAGE_BITS_ALL due to the page having been mmap()d). * With the page locked we are free to fix-up the dirty bits here. * * We do not under any circumstances truncate the valid bits, as * this will screw up bogus page replacement. */ VM_OBJECT_LOCK(object); if (maxsize + poffset > object->un_pager.vnp.vnp_size) { if (object->un_pager.vnp.vnp_size > poffset) { int pgoff; maxsize = object->un_pager.vnp.vnp_size - poffset; ncount = btoc(maxsize); if ((pgoff = (int)maxsize & PAGE_MASK) != 0) { /* * If the object is locked and the following * conditions hold, then the page's dirty * field cannot be concurrently changed by a * pmap operation. */ m = ma[ncount - 1]; KASSERT(m->busy > 0, ("vnode_pager_generic_putpages: page %p is not busy", m)); KASSERT(!pmap_page_is_write_mapped(m), ("vnode_pager_generic_putpages: page %p is not read-only", m)); vm_page_clear_dirty(m, pgoff, PAGE_SIZE - pgoff); } } else { maxsize = 0; ncount = 0; } if (ncount < count) { for (i = ncount; i < count; i++) { rtvals[i] = VM_PAGER_BAD; } } } VM_OBJECT_UNLOCK(object); /* * pageouts are already clustered, use IO_ASYNC to force a bawrite() * rather then a bdwrite() to prevent paging I/O from saturating * the buffer cache. Dummy-up the sequential heuristic to cause * large ranges to cluster. If neither IO_SYNC or IO_ASYNC is set, * the system decides how to cluster. */ ioflags = IO_VMIO; if (flags & (VM_PAGER_PUT_SYNC | VM_PAGER_PUT_INVAL)) ioflags |= IO_SYNC; else if ((flags & VM_PAGER_CLUSTER_OK) == 0) ioflags |= IO_ASYNC; ioflags |= (flags & VM_PAGER_PUT_INVAL) ? IO_INVAL: 0; ioflags |= IO_SEQMAX << IO_SEQSHIFT; aiov.iov_base = (caddr_t) 0; aiov.iov_len = maxsize; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = poffset; auio.uio_segflg = UIO_NOCOPY; auio.uio_rw = UIO_WRITE; auio.uio_resid = maxsize; auio.uio_td = (struct thread *) 0; error = VOP_WRITE(vp, &auio, ioflags, curthread->td_ucred); PCPU_INC(cnt.v_vnodeout); PCPU_ADD(cnt.v_vnodepgsout, ncount); if (error) { if ((ppscheck = ppsratecheck(&lastfail, &curfail, 1))) printf("vnode_pager_putpages: I/O error %d\n", error); } if (auio.uio_resid) { if (ppscheck || ppsratecheck(&lastfail, &curfail, 1)) printf("vnode_pager_putpages: residual I/O %zd at %lu\n", auio.uio_resid, (u_long)ma[0]->pindex); } for (i = 0; i < ncount; i++) { rtvals[i] = VM_PAGER_OK; } return rtvals[0]; } void vnode_pager_undirty_pages(vm_page_t *ma, int *rtvals, int written) { vm_object_t obj; int i, pos; if (written == 0) return; obj = ma[0]->object; VM_OBJECT_LOCK(obj); for (i = 0, pos = 0; pos < written; i++, pos += PAGE_SIZE) { if (pos < trunc_page(written)) { rtvals[i] = VM_PAGER_OK; vm_page_undirty(ma[i]); } else { /* Partially written page. */ rtvals[i] = VM_PAGER_AGAIN; vm_page_clear_dirty(ma[i], 0, written & PAGE_MASK); } } VM_OBJECT_UNLOCK(obj); } void vnode_pager_update_writecount(vm_object_t object, vm_offset_t start, vm_offset_t end) { struct vnode *vp; vm_ooffset_t old_wm; VM_OBJECT_LOCK(object); if (object->type != OBJT_VNODE) { VM_OBJECT_UNLOCK(object); return; } old_wm = object->un_pager.vnp.writemappings; object->un_pager.vnp.writemappings += (vm_ooffset_t)end - start; vp = object->handle; if (old_wm == 0 && object->un_pager.vnp.writemappings != 0) { ASSERT_VOP_ELOCKED(vp, "v_writecount inc"); VOP_ADD_WRITECOUNT(vp, 1); CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d", __func__, vp, vp->v_writecount); } else if (old_wm != 0 && object->un_pager.vnp.writemappings == 0) { ASSERT_VOP_ELOCKED(vp, "v_writecount dec"); VOP_ADD_WRITECOUNT(vp, -1); CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d", __func__, vp, vp->v_writecount); } VM_OBJECT_UNLOCK(object); } void vnode_pager_release_writecount(vm_object_t object, vm_offset_t start, vm_offset_t end) { struct vnode *vp; struct mount *mp; vm_offset_t inc; VM_OBJECT_LOCK(object); /* * First, recheck the object type to account for the race when * the vnode is reclaimed. */ if (object->type != OBJT_VNODE) { VM_OBJECT_UNLOCK(object); return; } /* * Optimize for the case when writemappings is not going to * zero. */ inc = end - start; if (object->un_pager.vnp.writemappings != inc) { object->un_pager.vnp.writemappings -= inc; VM_OBJECT_UNLOCK(object); return; } vp = object->handle; vhold(vp); VM_OBJECT_UNLOCK(object); mp = NULL; vn_start_write(vp, &mp, V_WAIT); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* * Decrement the object's writemappings, by swapping the start * and end arguments for vnode_pager_update_writecount(). If * there was not a race with vnode reclaimation, then the * vnode's v_writecount is decremented. */ vnode_pager_update_writecount(object, end, start); VOP_UNLOCK(vp, 0); vdrop(vp); if (mp != NULL) vn_finished_write(mp); }