Index: head/sys/fs/nfsclient/nfs_clbio.c =================================================================== --- head/sys/fs/nfsclient/nfs_clbio.c (revision 280188) +++ head/sys/fs/nfsclient/nfs_clbio.c (revision 280189) @@ -1,1889 +1,1891 @@ /*- * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Rick Macklem at The University of Guelph. * * 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. * * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern int newnfs_directio_allow_mmap; extern struct nfsstats newnfsstats; extern struct mtx ncl_iod_mutex; extern int ncl_numasync; extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON]; extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON]; extern int newnfs_directio_enable; extern int nfs_keep_dirty_on_error; int ncl_pbuf_freecnt = -1; /* start out unlimited */ static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td); static int nfs_directio_write(struct vnode *vp, struct uio *uiop, struct ucred *cred, int ioflag); /* * Vnode op for VM getpages. */ int ncl_getpages(struct vop_getpages_args *ap) { int i, error, nextoff, size, toff, count, npages; struct uio uio; struct iovec iov; vm_offset_t kva; struct buf *bp; struct vnode *vp; struct thread *td; struct ucred *cred; struct nfsmount *nmp; vm_object_t object; vm_page_t *pages; struct nfsnode *np; vp = ap->a_vp; np = VTONFS(vp); td = curthread; /* XXX */ cred = curthread->td_ucred; /* XXX */ nmp = VFSTONFS(vp->v_mount); pages = ap->a_m; count = ap->a_count; if ((object = vp->v_object) == NULL) { ncl_printf("nfs_getpages: called with non-merged cache vnode??\n"); return (VM_PAGER_ERROR); } if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { mtx_lock(&np->n_mtx); if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { mtx_unlock(&np->n_mtx); ncl_printf("nfs_getpages: called on non-cacheable vnode??\n"); return (VM_PAGER_ERROR); } else mtx_unlock(&np->n_mtx); } mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); /* We'll never get here for v4, because we always have fsinfo */ (void)ncl_fsinfo(nmp, vp, cred, td); } else mtx_unlock(&nmp->nm_mtx); npages = btoc(count); /* * Since the caller has busied the requested page, that page's valid * field will not be changed by other threads. */ vm_page_assert_xbusied(pages[ap->a_reqpage]); /* * If the requested page is partially valid, just return it and * allow the pager to zero-out the blanks. Partially valid pages * can only occur at the file EOF. */ if (pages[ap->a_reqpage]->valid != 0) { - vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages); + vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages, + FALSE); return (VM_PAGER_OK); } /* * We use only the kva address for the buffer, but this is extremely * convienient and fast. */ bp = getpbuf(&ncl_pbuf_freecnt); kva = (vm_offset_t) bp->b_data; pmap_qenter(kva, pages, npages); PCPU_INC(cnt.v_vnodein); PCPU_ADD(cnt.v_vnodepgsin, npages); iov.iov_base = (caddr_t) kva; iov.iov_len = count; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); uio.uio_resid = count; uio.uio_segflg = UIO_SYSSPACE; uio.uio_rw = UIO_READ; uio.uio_td = td; error = ncl_readrpc(vp, &uio, cred); pmap_qremove(kva, npages); relpbuf(bp, &ncl_pbuf_freecnt); if (error && (uio.uio_resid == count)) { ncl_printf("nfs_getpages: error %d\n", error); - vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages); + vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages, + FALSE); return (VM_PAGER_ERROR); } /* * Calculate the number of bytes read and validate only that number * of bytes. Note that due to pending writes, size may be 0. This * does not mean that the remaining data is invalid! */ size = count - uio.uio_resid; VM_OBJECT_WLOCK(object); for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { vm_page_t m; nextoff = toff + PAGE_SIZE; m = pages[i]; if (nextoff <= size) { /* * Read operation filled an entire page */ m->valid = VM_PAGE_BITS_ALL; KASSERT(m->dirty == 0, ("nfs_getpages: page %p is dirty", m)); } else if (size > toff) { /* * Read operation filled a partial page. */ m->valid = 0; vm_page_set_valid_range(m, 0, size - toff); KASSERT(m->dirty == 0, ("nfs_getpages: page %p is dirty", m)); } else { /* * Read operation was short. If no error * occured we may have hit a zero-fill * section. We leave valid set to 0, and page * is freed by vm_page_readahead_finish() if * its index is not equal to requested, or * page is zeroed and set valid by * vm_pager_get_pages() for requested page. */ ; } if (i != ap->a_reqpage) vm_page_readahead_finish(m); } VM_OBJECT_WUNLOCK(object); return (0); } /* * Vnode op for VM putpages. */ int ncl_putpages(struct vop_putpages_args *ap) { struct uio uio; struct iovec iov; vm_offset_t kva; struct buf *bp; int iomode, must_commit, i, error, npages, count; off_t offset; int *rtvals; struct vnode *vp; struct thread *td; struct ucred *cred; struct nfsmount *nmp; struct nfsnode *np; vm_page_t *pages; vp = ap->a_vp; np = VTONFS(vp); td = curthread; /* XXX */ /* Set the cred to n_writecred for the write rpcs. */ if (np->n_writecred != NULL) cred = crhold(np->n_writecred); else cred = crhold(curthread->td_ucred); /* XXX */ nmp = VFSTONFS(vp->v_mount); pages = ap->a_m; count = ap->a_count; rtvals = ap->a_rtvals; npages = btoc(count); offset = IDX_TO_OFF(pages[0]->pindex); mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); (void)ncl_fsinfo(nmp, vp, cred, td); } else mtx_unlock(&nmp->nm_mtx); mtx_lock(&np->n_mtx); if (newnfs_directio_enable && !newnfs_directio_allow_mmap && (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { mtx_unlock(&np->n_mtx); ncl_printf("ncl_putpages: called on noncache-able vnode??\n"); mtx_lock(&np->n_mtx); } for (i = 0; i < npages; i++) rtvals[i] = VM_PAGER_ERROR; /* * When putting pages, do not extend file past EOF. */ if (offset + count > np->n_size) { count = np->n_size - offset; if (count < 0) count = 0; } mtx_unlock(&np->n_mtx); /* * We use only the kva address for the buffer, but this is extremely * convienient and fast. */ bp = getpbuf(&ncl_pbuf_freecnt); kva = (vm_offset_t) bp->b_data; pmap_qenter(kva, pages, npages); PCPU_INC(cnt.v_vnodeout); PCPU_ADD(cnt.v_vnodepgsout, count); iov.iov_base = (caddr_t) kva; iov.iov_len = count; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = offset; uio.uio_resid = count; uio.uio_segflg = UIO_SYSSPACE; uio.uio_rw = UIO_WRITE; uio.uio_td = td; if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) iomode = NFSWRITE_UNSTABLE; else iomode = NFSWRITE_FILESYNC; error = ncl_writerpc(vp, &uio, cred, &iomode, &must_commit, 0); crfree(cred); pmap_qremove(kva, npages); relpbuf(bp, &ncl_pbuf_freecnt); if (error == 0 || !nfs_keep_dirty_on_error) { vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid); if (must_commit) ncl_clearcommit(vp->v_mount); } return rtvals[0]; } /* * For nfs, cache consistency can only be maintained approximately. * Although RFC1094 does not specify the criteria, the following is * believed to be compatible with the reference port. * For nfs: * If the file's modify time on the server has changed since the * last read rpc or you have written to the file, * you may have lost data cache consistency with the * server, so flush all of the file's data out of the cache. * Then force a getattr rpc to ensure that you have up to date * attributes. * NB: This implies that cache data can be read when up to * NFS_ATTRTIMEO seconds out of date. If you find that you need current * attributes this could be forced by setting n_attrstamp to 0 before * the VOP_GETATTR() call. */ static inline int nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) { int error = 0; struct vattr vattr; struct nfsnode *np = VTONFS(vp); int old_lock; /* * Grab the exclusive lock before checking whether the cache is * consistent. * XXX - We can make this cheaper later (by acquiring cheaper locks). * But for now, this suffices. */ old_lock = ncl_upgrade_vnlock(vp); if (vp->v_iflag & VI_DOOMED) { ncl_downgrade_vnlock(vp, old_lock); return (EBADF); } mtx_lock(&np->n_mtx); if (np->n_flag & NMODIFIED) { mtx_unlock(&np->n_mtx); if (vp->v_type != VREG) { if (vp->v_type != VDIR) panic("nfs: bioread, not dir"); ncl_invaldir(vp); error = ncl_vinvalbuf(vp, V_SAVE, td, 1); if (error) goto out; } np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); error = VOP_GETATTR(vp, &vattr, cred); if (error) goto out; mtx_lock(&np->n_mtx); np->n_mtime = vattr.va_mtime; mtx_unlock(&np->n_mtx); } else { mtx_unlock(&np->n_mtx); error = VOP_GETATTR(vp, &vattr, cred); if (error) return (error); mtx_lock(&np->n_mtx); if ((np->n_flag & NSIZECHANGED) || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { mtx_unlock(&np->n_mtx); if (vp->v_type == VDIR) ncl_invaldir(vp); error = ncl_vinvalbuf(vp, V_SAVE, td, 1); if (error) goto out; mtx_lock(&np->n_mtx); np->n_mtime = vattr.va_mtime; np->n_flag &= ~NSIZECHANGED; } mtx_unlock(&np->n_mtx); } out: ncl_downgrade_vnlock(vp, old_lock); return error; } /* * Vnode op for read using bio */ int ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) { struct nfsnode *np = VTONFS(vp); int biosize, i; struct buf *bp, *rabp; struct thread *td; struct nfsmount *nmp = VFSTONFS(vp->v_mount); daddr_t lbn, rabn; int bcount; int seqcount; int nra, error = 0, n = 0, on = 0; off_t tmp_off; KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); if (uio->uio_resid == 0) return (0); if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ return (EINVAL); td = uio->uio_td; mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); (void)ncl_fsinfo(nmp, vp, cred, td); mtx_lock(&nmp->nm_mtx); } if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) (void) newnfs_iosize(nmp); tmp_off = uio->uio_offset + uio->uio_resid; if (vp->v_type != VDIR && (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) { mtx_unlock(&nmp->nm_mtx); return (EFBIG); } mtx_unlock(&nmp->nm_mtx); if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) /* No caching/ no readaheads. Just read data into the user buffer */ return ncl_readrpc(vp, uio, cred); biosize = vp->v_bufobj.bo_bsize; seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); error = nfs_bioread_check_cons(vp, td, cred); if (error) return error; do { u_quad_t nsize; mtx_lock(&np->n_mtx); nsize = np->n_size; mtx_unlock(&np->n_mtx); switch (vp->v_type) { case VREG: NFSINCRGLOBAL(newnfsstats.biocache_reads); lbn = uio->uio_offset / biosize; on = uio->uio_offset - (lbn * biosize); /* * Start the read ahead(s), as required. */ if (nmp->nm_readahead > 0) { for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { rabn = lbn + 1 + nra; if (incore(&vp->v_bufobj, rabn) == NULL) { rabp = nfs_getcacheblk(vp, rabn, biosize, td); if (!rabp) { error = newnfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { rabp->b_flags |= B_ASYNC; rabp->b_iocmd = BIO_READ; vfs_busy_pages(rabp, 0); if (ncl_asyncio(nmp, rabp, cred, td)) { rabp->b_flags |= B_INVAL; rabp->b_ioflags |= BIO_ERROR; vfs_unbusy_pages(rabp); brelse(rabp); break; } } else { brelse(rabp); } } } } /* Note that bcount is *not* DEV_BSIZE aligned. */ bcount = biosize; if ((off_t)lbn * biosize >= nsize) { bcount = 0; } else if ((off_t)(lbn + 1) * biosize > nsize) { bcount = nsize - (off_t)lbn * biosize; } bp = nfs_getcacheblk(vp, lbn, bcount, td); if (!bp) { error = newnfs_sigintr(nmp, td); return (error ? error : EINTR); } /* * If B_CACHE is not set, we must issue the read. If this * fails, we return an error. */ if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = ncl_doio(vp, bp, cred, td, 0); if (error) { brelse(bp); return (error); } } /* * on is the offset into the current bp. Figure out how many * bytes we can copy out of the bp. Note that bcount is * NOT DEV_BSIZE aligned. * * Then figure out how many bytes we can copy into the uio. */ n = 0; if (on < bcount) n = MIN((unsigned)(bcount - on), uio->uio_resid); break; case VLNK: NFSINCRGLOBAL(newnfsstats.biocache_readlinks); bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); if (!bp) { error = newnfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = ncl_doio(vp, bp, cred, td, 0); if (error) { bp->b_ioflags |= BIO_ERROR; brelse(bp); return (error); } } n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); on = 0; break; case VDIR: NFSINCRGLOBAL(newnfsstats.biocache_readdirs); if (np->n_direofoffset && uio->uio_offset >= np->n_direofoffset) { return (0); } lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); if (!bp) { error = newnfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = ncl_doio(vp, bp, cred, td, 0); if (error) { brelse(bp); } while (error == NFSERR_BAD_COOKIE) { ncl_invaldir(vp); error = ncl_vinvalbuf(vp, 0, td, 1); /* * Yuck! The directory has been modified on the * server. The only way to get the block is by * reading from the beginning to get all the * offset cookies. * * Leave the last bp intact unless there is an error. * Loop back up to the while if the error is another * NFSERR_BAD_COOKIE (double yuch!). */ for (i = 0; i <= lbn && !error; i++) { if (np->n_direofoffset && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) return (0); bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); if (!bp) { error = newnfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = ncl_doio(vp, bp, cred, td, 0); /* * no error + B_INVAL == directory EOF, * use the block. */ if (error == 0 && (bp->b_flags & B_INVAL)) break; } /* * An error will throw away the block and the * for loop will break out. If no error and this * is not the block we want, we throw away the * block and go for the next one via the for loop. */ if (error || i < lbn) brelse(bp); } } /* * The above while is repeated if we hit another cookie * error. If we hit an error and it wasn't a cookie error, * we give up. */ if (error) return (error); } /* * If not eof and read aheads are enabled, start one. * (You need the current block first, so that you have the * directory offset cookie of the next block.) */ if (nmp->nm_readahead > 0 && (bp->b_flags & B_INVAL) == 0 && (np->n_direofoffset == 0 || (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && incore(&vp->v_bufobj, lbn + 1) == NULL) { rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); if (rabp) { if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { rabp->b_flags |= B_ASYNC; rabp->b_iocmd = BIO_READ; vfs_busy_pages(rabp, 0); if (ncl_asyncio(nmp, rabp, cred, td)) { rabp->b_flags |= B_INVAL; rabp->b_ioflags |= BIO_ERROR; vfs_unbusy_pages(rabp); brelse(rabp); } } else { brelse(rabp); } } } /* * Unlike VREG files, whos buffer size ( bp->b_bcount ) is * chopped for the EOF condition, we cannot tell how large * NFS directories are going to be until we hit EOF. So * an NFS directory buffer is *not* chopped to its EOF. Now, * it just so happens that b_resid will effectively chop it * to EOF. *BUT* this information is lost if the buffer goes * away and is reconstituted into a B_CACHE state ( due to * being VMIO ) later. So we keep track of the directory eof * in np->n_direofoffset and chop it off as an extra step * right here. */ n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) n = np->n_direofoffset - uio->uio_offset; break; default: ncl_printf(" ncl_bioread: type %x unexpected\n", vp->v_type); bp = NULL; break; }; if (n > 0) { error = vn_io_fault_uiomove(bp->b_data + on, (int)n, uio); } if (vp->v_type == VLNK) n = 0; if (bp != NULL) brelse(bp); } while (error == 0 && uio->uio_resid > 0 && n > 0); return (error); } /* * The NFS write path cannot handle iovecs with len > 1. So we need to * break up iovecs accordingly (restricting them to wsize). * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). * For the ASYNC case, 2 copies are needed. The first a copy from the * user buffer to a staging buffer and then a second copy from the staging * buffer to mbufs. This can be optimized by copying from the user buffer * directly into mbufs and passing the chain down, but that requires a * fair amount of re-working of the relevant codepaths (and can be done * later). */ static int nfs_directio_write(vp, uiop, cred, ioflag) struct vnode *vp; struct uio *uiop; struct ucred *cred; int ioflag; { int error; struct nfsmount *nmp = VFSTONFS(vp->v_mount); struct thread *td = uiop->uio_td; int size; int wsize; mtx_lock(&nmp->nm_mtx); wsize = nmp->nm_wsize; mtx_unlock(&nmp->nm_mtx); if (ioflag & IO_SYNC) { int iomode, must_commit; struct uio uio; struct iovec iov; do_sync: while (uiop->uio_resid > 0) { size = MIN(uiop->uio_resid, wsize); size = MIN(uiop->uio_iov->iov_len, size); iov.iov_base = uiop->uio_iov->iov_base; iov.iov_len = size; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = uiop->uio_offset; uio.uio_resid = size; uio.uio_segflg = UIO_USERSPACE; uio.uio_rw = UIO_WRITE; uio.uio_td = td; iomode = NFSWRITE_FILESYNC; error = ncl_writerpc(vp, &uio, cred, &iomode, &must_commit, 0); KASSERT((must_commit == 0), ("ncl_directio_write: Did not commit write")); if (error) return (error); uiop->uio_offset += size; uiop->uio_resid -= size; if (uiop->uio_iov->iov_len <= size) { uiop->uio_iovcnt--; uiop->uio_iov++; } else { uiop->uio_iov->iov_base = (char *)uiop->uio_iov->iov_base + size; uiop->uio_iov->iov_len -= size; } } } else { struct uio *t_uio; struct iovec *t_iov; struct buf *bp; /* * Break up the write into blocksize chunks and hand these * over to nfsiod's for write back. * Unfortunately, this incurs a copy of the data. Since * the user could modify the buffer before the write is * initiated. * * The obvious optimization here is that one of the 2 copies * in the async write path can be eliminated by copying the * data here directly into mbufs and passing the mbuf chain * down. But that will require a fair amount of re-working * of the code and can be done if there's enough interest * in NFS directio access. */ while (uiop->uio_resid > 0) { size = MIN(uiop->uio_resid, wsize); size = MIN(uiop->uio_iov->iov_len, size); bp = getpbuf(&ncl_pbuf_freecnt); t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); t_iov->iov_len = size; t_uio->uio_iov = t_iov; t_uio->uio_iovcnt = 1; t_uio->uio_offset = uiop->uio_offset; t_uio->uio_resid = size; t_uio->uio_segflg = UIO_SYSSPACE; t_uio->uio_rw = UIO_WRITE; t_uio->uio_td = td; KASSERT(uiop->uio_segflg == UIO_USERSPACE || uiop->uio_segflg == UIO_SYSSPACE, ("nfs_directio_write: Bad uio_segflg")); if (uiop->uio_segflg == UIO_USERSPACE) { error = copyin(uiop->uio_iov->iov_base, t_iov->iov_base, size); if (error != 0) goto err_free; } else /* * UIO_SYSSPACE may never happen, but handle * it just in case it does. */ bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, size); bp->b_flags |= B_DIRECT; bp->b_iocmd = BIO_WRITE; if (cred != NOCRED) { crhold(cred); bp->b_wcred = cred; } else bp->b_wcred = NOCRED; bp->b_caller1 = (void *)t_uio; bp->b_vp = vp; error = ncl_asyncio(nmp, bp, NOCRED, td); err_free: if (error) { free(t_iov->iov_base, M_NFSDIRECTIO); free(t_iov, M_NFSDIRECTIO); free(t_uio, M_NFSDIRECTIO); bp->b_vp = NULL; relpbuf(bp, &ncl_pbuf_freecnt); if (error == EINTR) return (error); goto do_sync; } uiop->uio_offset += size; uiop->uio_resid -= size; if (uiop->uio_iov->iov_len <= size) { uiop->uio_iovcnt--; uiop->uio_iov++; } else { uiop->uio_iov->iov_base = (char *)uiop->uio_iov->iov_base + size; uiop->uio_iov->iov_len -= size; } } } return (0); } /* * Vnode op for write using bio */ int ncl_write(struct vop_write_args *ap) { int biosize; struct uio *uio = ap->a_uio; struct thread *td = uio->uio_td; struct vnode *vp = ap->a_vp; struct nfsnode *np = VTONFS(vp); struct ucred *cred = ap->a_cred; int ioflag = ap->a_ioflag; struct buf *bp; struct vattr vattr; struct nfsmount *nmp = VFSTONFS(vp->v_mount); daddr_t lbn; int bcount, noncontig_write, obcount; int bp_cached, n, on, error = 0, error1; size_t orig_resid, local_resid; off_t orig_size, tmp_off; KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, ("ncl_write proc")); if (vp->v_type != VREG) return (EIO); mtx_lock(&np->n_mtx); if (np->n_flag & NWRITEERR) { np->n_flag &= ~NWRITEERR; mtx_unlock(&np->n_mtx); return (np->n_error); } else mtx_unlock(&np->n_mtx); mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); (void)ncl_fsinfo(nmp, vp, cred, td); mtx_lock(&nmp->nm_mtx); } if (nmp->nm_wsize == 0) (void) newnfs_iosize(nmp); mtx_unlock(&nmp->nm_mtx); /* * Synchronously flush pending buffers if we are in synchronous * mode or if we are appending. */ if (ioflag & (IO_APPEND | IO_SYNC)) { mtx_lock(&np->n_mtx); if (np->n_flag & NMODIFIED) { mtx_unlock(&np->n_mtx); #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ /* * Require non-blocking, synchronous writes to * dirty files to inform the program it needs * to fsync(2) explicitly. */ if (ioflag & IO_NDELAY) return (EAGAIN); #endif flush_and_restart: np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); error = ncl_vinvalbuf(vp, V_SAVE, td, 1); if (error) return (error); } else mtx_unlock(&np->n_mtx); } orig_resid = uio->uio_resid; mtx_lock(&np->n_mtx); orig_size = np->n_size; mtx_unlock(&np->n_mtx); /* * If IO_APPEND then load uio_offset. We restart here if we cannot * get the append lock. */ if (ioflag & IO_APPEND) { np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); error = VOP_GETATTR(vp, &vattr, cred); if (error) return (error); mtx_lock(&np->n_mtx); uio->uio_offset = np->n_size; mtx_unlock(&np->n_mtx); } if (uio->uio_offset < 0) return (EINVAL); tmp_off = uio->uio_offset + uio->uio_resid; if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) return (EFBIG); if (uio->uio_resid == 0) return (0); if (newnfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) return nfs_directio_write(vp, uio, cred, ioflag); /* * Maybe this should be above the vnode op call, but so long as * file servers have no limits, i don't think it matters */ if (vn_rlimit_fsize(vp, uio, td)) return (EFBIG); biosize = vp->v_bufobj.bo_bsize; /* * Find all of this file's B_NEEDCOMMIT buffers. If our writes * would exceed the local maximum per-file write commit size when * combined with those, we must decide whether to flush, * go synchronous, or return error. We don't bother checking * IO_UNIT -- we just make all writes atomic anyway, as there's * no point optimizing for something that really won't ever happen. */ if (!(ioflag & IO_SYNC)) { int nflag; mtx_lock(&np->n_mtx); nflag = np->n_flag; mtx_unlock(&np->n_mtx); int needrestart = 0; if (nmp->nm_wcommitsize < uio->uio_resid) { /* * If this request could not possibly be completed * without exceeding the maximum outstanding write * commit size, see if we can convert it into a * synchronous write operation. */ if (ioflag & IO_NDELAY) return (EAGAIN); ioflag |= IO_SYNC; if (nflag & NMODIFIED) needrestart = 1; } else if (nflag & NMODIFIED) { int wouldcommit = 0; BO_LOCK(&vp->v_bufobj); if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs) { if (bp->b_flags & B_NEEDCOMMIT) wouldcommit += bp->b_bcount; } } BO_UNLOCK(&vp->v_bufobj); /* * Since we're not operating synchronously and * bypassing the buffer cache, we are in a commit * and holding all of these buffers whether * transmitted or not. If not limited, this * will lead to the buffer cache deadlocking, * as no one else can flush our uncommitted buffers. */ wouldcommit += uio->uio_resid; /* * If we would initially exceed the maximum * outstanding write commit size, flush and restart. */ if (wouldcommit > nmp->nm_wcommitsize) needrestart = 1; } if (needrestart) goto flush_and_restart; } do { NFSINCRGLOBAL(newnfsstats.biocache_writes); lbn = uio->uio_offset / biosize; on = uio->uio_offset - (lbn * biosize); n = MIN((unsigned)(biosize - on), uio->uio_resid); again: /* * Handle direct append and file extension cases, calculate * unaligned buffer size. */ mtx_lock(&np->n_mtx); if ((np->n_flag & NHASBEENLOCKED) == 0 && (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0) noncontig_write = 1; else noncontig_write = 0; if ((uio->uio_offset == np->n_size || (noncontig_write != 0 && lbn == (np->n_size / biosize) && uio->uio_offset + n > np->n_size)) && n) { mtx_unlock(&np->n_mtx); /* * Get the buffer (in its pre-append state to maintain * B_CACHE if it was previously set). Resize the * nfsnode after we have locked the buffer to prevent * readers from reading garbage. */ obcount = np->n_size - (lbn * biosize); bp = nfs_getcacheblk(vp, lbn, obcount, td); if (bp != NULL) { long save; mtx_lock(&np->n_mtx); np->n_size = uio->uio_offset + n; np->n_flag |= NMODIFIED; vnode_pager_setsize(vp, np->n_size); mtx_unlock(&np->n_mtx); save = bp->b_flags & B_CACHE; bcount = on + n; allocbuf(bp, bcount); bp->b_flags |= save; if (noncontig_write != 0 && on > obcount) vfs_bio_bzero_buf(bp, obcount, on - obcount); } } else { /* * Obtain the locked cache block first, and then * adjust the file's size as appropriate. */ bcount = on + n; if ((off_t)lbn * biosize + bcount < np->n_size) { if ((off_t)(lbn + 1) * biosize < np->n_size) bcount = biosize; else bcount = np->n_size - (off_t)lbn * biosize; } mtx_unlock(&np->n_mtx); bp = nfs_getcacheblk(vp, lbn, bcount, td); mtx_lock(&np->n_mtx); if (uio->uio_offset + n > np->n_size) { np->n_size = uio->uio_offset + n; np->n_flag |= NMODIFIED; vnode_pager_setsize(vp, np->n_size); } mtx_unlock(&np->n_mtx); } if (!bp) { error = newnfs_sigintr(nmp, td); if (!error) error = EINTR; break; } /* * Issue a READ if B_CACHE is not set. In special-append * mode, B_CACHE is based on the buffer prior to the write * op and is typically set, avoiding the read. If a read * is required in special append mode, the server will * probably send us a short-read since we extended the file * on our end, resulting in b_resid == 0 and, thusly, * B_CACHE getting set. * * We can also avoid issuing the read if the write covers * the entire buffer. We have to make sure the buffer state * is reasonable in this case since we will not be initiating * I/O. See the comments in kern/vfs_bio.c's getblk() for * more information. * * B_CACHE may also be set due to the buffer being cached * normally. */ bp_cached = 1; if (on == 0 && n == bcount) { if ((bp->b_flags & B_CACHE) == 0) bp_cached = 0; bp->b_flags |= B_CACHE; bp->b_flags &= ~B_INVAL; bp->b_ioflags &= ~BIO_ERROR; } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = ncl_doio(vp, bp, cred, td, 0); if (error) { brelse(bp); break; } } if (bp->b_wcred == NOCRED) bp->b_wcred = crhold(cred); mtx_lock(&np->n_mtx); np->n_flag |= NMODIFIED; mtx_unlock(&np->n_mtx); /* * If dirtyend exceeds file size, chop it down. This should * not normally occur but there is an append race where it * might occur XXX, so we log it. * * If the chopping creates a reverse-indexed or degenerate * situation with dirtyoff/end, we 0 both of them. */ if (bp->b_dirtyend > bcount) { ncl_printf("NFS append race @%lx:%d\n", (long)bp->b_blkno * DEV_BSIZE, bp->b_dirtyend - bcount); bp->b_dirtyend = bcount; } if (bp->b_dirtyoff >= bp->b_dirtyend) bp->b_dirtyoff = bp->b_dirtyend = 0; /* * If the new write will leave a contiguous dirty * area, just update the b_dirtyoff and b_dirtyend, * otherwise force a write rpc of the old dirty area. * * If there has been a file lock applied to this file * or vfs.nfs.old_noncontig_writing is set, do the following: * While it is possible to merge discontiguous writes due to * our having a B_CACHE buffer ( and thus valid read data * for the hole), we don't because it could lead to * significant cache coherency problems with multiple clients, * especially if locking is implemented later on. * * If vfs.nfs.old_noncontig_writing is not set and there has * not been file locking done on this file: * Relax coherency a bit for the sake of performance and * expand the current dirty region to contain the new * write even if it means we mark some non-dirty data as * dirty. */ if (noncontig_write == 0 && bp->b_dirtyend > 0 && (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { if (bwrite(bp) == EINTR) { error = EINTR; break; } goto again; } local_resid = uio->uio_resid; error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio); if (error != 0 && !bp_cached) { /* * This block has no other content then what * possibly was written by the faulty uiomove. * Release it, forgetting the data pages, to * prevent the leak of uninitialized data to * usermode. */ bp->b_ioflags |= BIO_ERROR; brelse(bp); uio->uio_offset -= local_resid - uio->uio_resid; uio->uio_resid = local_resid; break; } /* * Since this block is being modified, it must be written * again and not just committed. Since write clustering does * not work for the stage 1 data write, only the stage 2 * commit rpc, we have to clear B_CLUSTEROK as well. */ bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); /* * Get the partial update on the progress made from * uiomove, if an error occured. */ if (error != 0) n = local_resid - uio->uio_resid; /* * Only update dirtyoff/dirtyend if not a degenerate * condition. */ if (n > 0) { if (bp->b_dirtyend > 0) { bp->b_dirtyoff = min(on, bp->b_dirtyoff); bp->b_dirtyend = max((on + n), bp->b_dirtyend); } else { bp->b_dirtyoff = on; bp->b_dirtyend = on + n; } vfs_bio_set_valid(bp, on, n); } /* * If IO_SYNC do bwrite(). * * IO_INVAL appears to be unused. The idea appears to be * to turn off caching in this case. Very odd. XXX */ if ((ioflag & IO_SYNC)) { if (ioflag & IO_INVAL) bp->b_flags |= B_NOCACHE; error1 = bwrite(bp); if (error1 != 0) { if (error == 0) error = error1; break; } } else if ((n + on) == biosize) { bp->b_flags |= B_ASYNC; (void) ncl_writebp(bp, 0, NULL); } else { bdwrite(bp); } if (error != 0) break; } while (uio->uio_resid > 0 && n > 0); if (error != 0) { if (ioflag & IO_UNIT) { VATTR_NULL(&vattr); vattr.va_size = orig_size; /* IO_SYNC is handled implicitely */ (void)VOP_SETATTR(vp, &vattr, cred); uio->uio_offset -= orig_resid - uio->uio_resid; uio->uio_resid = orig_resid; } } return (error); } /* * Get an nfs cache block. * * Allocate a new one if the block isn't currently in the cache * and return the block marked busy. If the calling process is * interrupted by a signal for an interruptible mount point, return * NULL. * * The caller must carefully deal with the possible B_INVAL state of * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it * indirectly), so synchronous reads can be issued without worrying about * the B_INVAL state. We have to be a little more careful when dealing * with writes (see comments in nfs_write()) when extending a file past * its EOF. */ static struct buf * nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) { struct buf *bp; struct mount *mp; struct nfsmount *nmp; mp = vp->v_mount; nmp = VFSTONFS(mp); if (nmp->nm_flag & NFSMNT_INT) { sigset_t oldset; newnfs_set_sigmask(td, &oldset); bp = getblk(vp, bn, size, PCATCH, 0, 0); newnfs_restore_sigmask(td, &oldset); while (bp == NULL) { if (newnfs_sigintr(nmp, td)) return (NULL); bp = getblk(vp, bn, size, 0, 2 * hz, 0); } } else { bp = getblk(vp, bn, size, 0, 0, 0); } if (vp->v_type == VREG) bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); return (bp); } /* * Flush and invalidate all dirty buffers. If another process is already * doing the flush, just wait for completion. */ int ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) { struct nfsnode *np = VTONFS(vp); struct nfsmount *nmp = VFSTONFS(vp->v_mount); int error = 0, slpflag, slptimeo; int old_lock = 0; ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); if ((nmp->nm_flag & NFSMNT_INT) == 0) intrflg = 0; if ((nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)) intrflg = 1; if (intrflg) { slpflag = PCATCH; slptimeo = 2 * hz; } else { slpflag = 0; slptimeo = 0; } old_lock = ncl_upgrade_vnlock(vp); if (vp->v_iflag & VI_DOOMED) { /* * Since vgonel() uses the generic vinvalbuf() to flush * dirty buffers and it does not call this function, it * is safe to just return OK when VI_DOOMED is set. */ ncl_downgrade_vnlock(vp, old_lock); return (0); } /* * Now, flush as required. */ if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); /* * If the page clean was interrupted, fail the invalidation. * Not doing so, we run the risk of losing dirty pages in the * vinvalbuf() call below. */ if (intrflg && (error = newnfs_sigintr(nmp, td))) goto out; } error = vinvalbuf(vp, flags, slpflag, 0); while (error) { if (intrflg && (error = newnfs_sigintr(nmp, td))) goto out; error = vinvalbuf(vp, flags, 0, slptimeo); } if (NFSHASPNFS(nmp)) { nfscl_layoutcommit(vp, td); /* * Invalidate the attribute cache, since writes to a DS * won't update the size attribute. */ mtx_lock(&np->n_mtx); np->n_attrstamp = 0; } else mtx_lock(&np->n_mtx); if (np->n_directio_asyncwr == 0) np->n_flag &= ~NMODIFIED; mtx_unlock(&np->n_mtx); out: ncl_downgrade_vnlock(vp, old_lock); return error; } /* * Initiate asynchronous I/O. Return an error if no nfsiods are available. * This is mainly to avoid queueing async I/O requests when the nfsiods * are all hung on a dead server. * * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp * is eventually dequeued by the async daemon, ncl_doio() *will*. */ int ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) { int iod; int gotiod; int slpflag = 0; int slptimeo = 0; int error, error2; /* * Commits are usually short and sweet so lets save some cpu and * leave the async daemons for more important rpc's (such as reads * and writes). * * Readdirplus RPCs do vget()s to acquire the vnodes for entries * in the directory in order to update attributes. This can deadlock * with another thread that is waiting for async I/O to be done by * an nfsiod thread while holding a lock on one of these vnodes. * To avoid this deadlock, don't allow the async nfsiod threads to * perform Readdirplus RPCs. */ mtx_lock(&ncl_iod_mutex); if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && (nmp->nm_bufqiods > ncl_numasync / 2)) || (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { mtx_unlock(&ncl_iod_mutex); return(EIO); } again: if (nmp->nm_flag & NFSMNT_INT) slpflag = PCATCH; gotiod = FALSE; /* * Find a free iod to process this request. */ for (iod = 0; iod < ncl_numasync; iod++) if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { gotiod = TRUE; break; } /* * Try to create one if none are free. */ if (!gotiod) ncl_nfsiodnew(); else { /* * Found one, so wake it up and tell it which * mount to process. */ NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", iod, nmp)); ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; ncl_iodmount[iod] = nmp; nmp->nm_bufqiods++; wakeup(&ncl_iodwant[iod]); } /* * If none are free, we may already have an iod working on this mount * point. If so, it will process our request. */ if (!gotiod) { if (nmp->nm_bufqiods > 0) { NFS_DPF(ASYNCIO, ("ncl_asyncio: %d iods are already processing mount %p\n", nmp->nm_bufqiods, nmp)); gotiod = TRUE; } } /* * If we have an iod which can process the request, then queue * the buffer. */ if (gotiod) { /* * Ensure that the queue never grows too large. We still want * to asynchronize so we block rather then return EIO. */ while (nmp->nm_bufqlen >= 2*ncl_numasync) { NFS_DPF(ASYNCIO, ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); nmp->nm_bufqwant = TRUE; error = newnfs_msleep(td, &nmp->nm_bufq, &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", slptimeo); if (error) { error2 = newnfs_sigintr(nmp, td); if (error2) { mtx_unlock(&ncl_iod_mutex); return (error2); } if (slpflag == PCATCH) { slpflag = 0; slptimeo = 2 * hz; } } /* * We might have lost our iod while sleeping, * so check and loop if nescessary. */ goto again; } /* We might have lost our nfsiod */ if (nmp->nm_bufqiods == 0) { NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); goto again; } if (bp->b_iocmd == BIO_READ) { if (bp->b_rcred == NOCRED && cred != NOCRED) bp->b_rcred = crhold(cred); } else { if (bp->b_wcred == NOCRED && cred != NOCRED) bp->b_wcred = crhold(cred); } if (bp->b_flags & B_REMFREE) bremfreef(bp); BUF_KERNPROC(bp); TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); nmp->nm_bufqlen++; if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); VTONFS(bp->b_vp)->n_flag |= NMODIFIED; VTONFS(bp->b_vp)->n_directio_asyncwr++; mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); } mtx_unlock(&ncl_iod_mutex); return (0); } mtx_unlock(&ncl_iod_mutex); /* * All the iods are busy on other mounts, so return EIO to * force the caller to process the i/o synchronously. */ NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); return (EIO); } void ncl_doio_directwrite(struct buf *bp) { int iomode, must_commit; struct uio *uiop = (struct uio *)bp->b_caller1; char *iov_base = uiop->uio_iov->iov_base; iomode = NFSWRITE_FILESYNC; uiop->uio_td = NULL; /* NULL since we're in nfsiod */ ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); KASSERT((must_commit == 0), ("ncl_doio_directwrite: Did not commit write")); free(iov_base, M_NFSDIRECTIO); free(uiop->uio_iov, M_NFSDIRECTIO); free(uiop, M_NFSDIRECTIO); if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { struct nfsnode *np = VTONFS(bp->b_vp); mtx_lock(&np->n_mtx); if (NFSHASPNFS(VFSTONFS(vnode_mount(bp->b_vp)))) { /* * Invalidate the attribute cache, since writes to a DS * won't update the size attribute. */ np->n_attrstamp = 0; } np->n_directio_asyncwr--; if (np->n_directio_asyncwr == 0) { np->n_flag &= ~NMODIFIED; if ((np->n_flag & NFSYNCWAIT)) { np->n_flag &= ~NFSYNCWAIT; wakeup((caddr_t)&np->n_directio_asyncwr); } } mtx_unlock(&np->n_mtx); } bp->b_vp = NULL; relpbuf(bp, &ncl_pbuf_freecnt); } /* * Do an I/O operation to/from a cache block. This may be called * synchronously or from an nfsiod. */ int ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, int called_from_strategy) { struct uio *uiop; struct nfsnode *np; struct nfsmount *nmp; int error = 0, iomode, must_commit = 0; struct uio uio; struct iovec io; struct proc *p = td ? td->td_proc : NULL; uint8_t iocmd; np = VTONFS(vp); nmp = VFSTONFS(vp->v_mount); uiop = &uio; uiop->uio_iov = &io; uiop->uio_iovcnt = 1; uiop->uio_segflg = UIO_SYSSPACE; uiop->uio_td = td; /* * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We * do this here so we do not have to do it in all the code that * calls us. */ bp->b_flags &= ~B_INVAL; bp->b_ioflags &= ~BIO_ERROR; KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); iocmd = bp->b_iocmd; if (iocmd == BIO_READ) { io.iov_len = uiop->uio_resid = bp->b_bcount; io.iov_base = bp->b_data; uiop->uio_rw = UIO_READ; switch (vp->v_type) { case VREG: uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; NFSINCRGLOBAL(newnfsstats.read_bios); error = ncl_readrpc(vp, uiop, cr); if (!error) { if (uiop->uio_resid) { /* * If we had a short read with no error, we must have * hit a file hole. We should zero-fill the remainder. * This can also occur if the server hits the file EOF. * * Holes used to be able to occur due to pending * writes, but that is not possible any longer. */ int nread = bp->b_bcount - uiop->uio_resid; ssize_t left = uiop->uio_resid; if (left > 0) bzero((char *)bp->b_data + nread, left); uiop->uio_resid = 0; } } /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ if (p && (vp->v_vflag & VV_TEXT)) { mtx_lock(&np->n_mtx); if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { mtx_unlock(&np->n_mtx); PROC_LOCK(p); killproc(p, "text file modification"); PROC_UNLOCK(p); } else mtx_unlock(&np->n_mtx); } break; case VLNK: uiop->uio_offset = (off_t)0; NFSINCRGLOBAL(newnfsstats.readlink_bios); error = ncl_readlinkrpc(vp, uiop, cr); break; case VDIR: NFSINCRGLOBAL(newnfsstats.readdir_bios); uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { error = ncl_readdirplusrpc(vp, uiop, cr, td); if (error == NFSERR_NOTSUPP) nmp->nm_flag &= ~NFSMNT_RDIRPLUS; } if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) error = ncl_readdirrpc(vp, uiop, cr, td); /* * end-of-directory sets B_INVAL but does not generate an * error. */ if (error == 0 && uiop->uio_resid == bp->b_bcount) bp->b_flags |= B_INVAL; break; default: ncl_printf("ncl_doio: type %x unexpected\n", vp->v_type); break; }; if (error) { bp->b_ioflags |= BIO_ERROR; bp->b_error = error; } } else { /* * If we only need to commit, try to commit */ if (bp->b_flags & B_NEEDCOMMIT) { int retv; off_t off; off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, bp->b_wcred, td); if (retv == 0) { bp->b_dirtyoff = bp->b_dirtyend = 0; bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); bp->b_resid = 0; bufdone(bp); return (0); } if (retv == NFSERR_STALEWRITEVERF) { ncl_clearcommit(vp->v_mount); } } /* * Setup for actual write */ mtx_lock(&np->n_mtx); if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; mtx_unlock(&np->n_mtx); if (bp->b_dirtyend > bp->b_dirtyoff) { io.iov_len = uiop->uio_resid = bp->b_dirtyend - bp->b_dirtyoff; uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyoff; io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; uiop->uio_rw = UIO_WRITE; NFSINCRGLOBAL(newnfsstats.write_bios); if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) iomode = NFSWRITE_UNSTABLE; else iomode = NFSWRITE_FILESYNC; error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, called_from_strategy); /* * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try * to cluster the buffers needing commit. This will allow * the system to submit a single commit rpc for the whole * cluster. We can do this even if the buffer is not 100% * dirty (relative to the NFS blocksize), so we optimize the * append-to-file-case. * * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be * cleared because write clustering only works for commit * rpc's, not for the data portion of the write). */ if (!error && iomode == NFSWRITE_UNSTABLE) { bp->b_flags |= B_NEEDCOMMIT; if (bp->b_dirtyoff == 0 && bp->b_dirtyend == bp->b_bcount) bp->b_flags |= B_CLUSTEROK; } else { bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); } /* * For an interrupted write, the buffer is still valid * and the write hasn't been pushed to the server yet, * so we can't set BIO_ERROR and report the interruption * by setting B_EINTR. For the B_ASYNC case, B_EINTR * is not relevant, so the rpc attempt is essentially * a noop. For the case of a V3 write rpc not being * committed to stable storage, the block is still * dirty and requires either a commit rpc or another * write rpc with iomode == NFSV3WRITE_FILESYNC before * the block is reused. This is indicated by setting * the B_DELWRI and B_NEEDCOMMIT flags. * * EIO is returned by ncl_writerpc() to indicate a recoverable * write error and is handled as above, except that * B_EINTR isn't set. One cause of this is a stale stateid * error for the RPC that indicates recovery is required, * when called with called_from_strategy != 0. * * If the buffer is marked B_PAGING, it does not reside on * the vp's paging queues so we cannot call bdirty(). The * bp in this case is not an NFS cache block so we should * be safe. XXX * * The logic below breaks up errors into recoverable and * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE * and keep the buffer around for potential write retries. * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) * and save the error in the nfsnode. This is less than ideal * but necessary. Keeping such buffers around could potentially * cause buffer exhaustion eventually (they can never be written * out, so will get constantly be re-dirtied). It also causes * all sorts of vfs panics. For non-recoverable write errors, * also invalidate the attrcache, so we'll be forced to go over * the wire for this object, returning an error to user on next * call (most of the time). */ if (error == EINTR || error == EIO || error == ETIMEDOUT || (!error && (bp->b_flags & B_NEEDCOMMIT))) { int s; s = splbio(); bp->b_flags &= ~(B_INVAL|B_NOCACHE); if ((bp->b_flags & B_PAGING) == 0) { bdirty(bp); bp->b_flags &= ~B_DONE; } if ((error == EINTR || error == ETIMEDOUT) && (bp->b_flags & B_ASYNC) == 0) bp->b_flags |= B_EINTR; splx(s); } else { if (error) { bp->b_ioflags |= BIO_ERROR; bp->b_flags |= B_INVAL; bp->b_error = np->n_error = error; mtx_lock(&np->n_mtx); np->n_flag |= NWRITEERR; np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); mtx_unlock(&np->n_mtx); } bp->b_dirtyoff = bp->b_dirtyend = 0; } } else { bp->b_resid = 0; bufdone(bp); return (0); } } bp->b_resid = uiop->uio_resid; if (must_commit) ncl_clearcommit(vp->v_mount); bufdone(bp); return (error); } /* * Used to aid in handling ftruncate() operations on the NFS client side. * Truncation creates a number of special problems for NFS. We have to * throw away VM pages and buffer cache buffers that are beyond EOF, and * we have to properly handle VM pages or (potentially dirty) buffers * that straddle the truncation point. */ int ncl_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) { struct nfsnode *np = VTONFS(vp); u_quad_t tsize; int biosize = vp->v_bufobj.bo_bsize; int error = 0; mtx_lock(&np->n_mtx); tsize = np->n_size; np->n_size = nsize; mtx_unlock(&np->n_mtx); if (nsize < tsize) { struct buf *bp; daddr_t lbn; int bufsize; /* * vtruncbuf() doesn't get the buffer overlapping the * truncation point. We may have a B_DELWRI and/or B_CACHE * buffer that now needs to be truncated. */ error = vtruncbuf(vp, cred, nsize, biosize); lbn = nsize / biosize; bufsize = nsize - (lbn * biosize); bp = nfs_getcacheblk(vp, lbn, bufsize, td); if (!bp) return EINTR; if (bp->b_dirtyoff > bp->b_bcount) bp->b_dirtyoff = bp->b_bcount; if (bp->b_dirtyend > bp->b_bcount) bp->b_dirtyend = bp->b_bcount; bp->b_flags |= B_RELBUF; /* don't leave garbage around */ brelse(bp); } else { vnode_pager_setsize(vp, nsize); } return(error); } Index: head/sys/vm/vm_pager.c =================================================================== --- head/sys/vm/vm_pager.c (revision 280188) +++ head/sys/vm/vm_pager.c (revision 280189) @@ -1,518 +1,524 @@ /*- * 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_pager.c 8.6 (Berkeley) 1/12/94 * * * 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. */ /* * Paging space routine stubs. Emulates a matchmaker-like interface * for builtin pagers. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include int cluster_pbuf_freecnt = -1; /* unlimited to begin with */ static int dead_pager_getpages(vm_object_t, vm_page_t *, int, int); static vm_object_t dead_pager_alloc(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); static void dead_pager_putpages(vm_object_t, vm_page_t *, int, int, int *); static boolean_t dead_pager_haspage(vm_object_t, vm_pindex_t, int *, int *); static void dead_pager_dealloc(vm_object_t); static int dead_pager_getpages(obj, ma, count, req) vm_object_t obj; vm_page_t *ma; int count; int req; { return VM_PAGER_FAIL; } static vm_object_t dead_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t off, struct ucred *cred) { return NULL; } static void dead_pager_putpages(object, m, count, flags, rtvals) vm_object_t object; vm_page_t *m; int count; int flags; int *rtvals; { int i; for (i = 0; i < count; i++) { rtvals[i] = VM_PAGER_AGAIN; } } static int dead_pager_haspage(object, pindex, prev, next) vm_object_t object; vm_pindex_t pindex; int *prev; int *next; { if (prev) *prev = 0; if (next) *next = 0; return FALSE; } static void dead_pager_dealloc(object) vm_object_t object; { return; } static struct pagerops deadpagerops = { .pgo_alloc = dead_pager_alloc, .pgo_dealloc = dead_pager_dealloc, .pgo_getpages = dead_pager_getpages, .pgo_putpages = dead_pager_putpages, .pgo_haspage = dead_pager_haspage, }; struct pagerops *pagertab[] = { &defaultpagerops, /* OBJT_DEFAULT */ &swappagerops, /* OBJT_SWAP */ &vnodepagerops, /* OBJT_VNODE */ &devicepagerops, /* OBJT_DEVICE */ &physpagerops, /* OBJT_PHYS */ &deadpagerops, /* OBJT_DEAD */ &sgpagerops, /* OBJT_SG */ &mgtdevicepagerops, /* OBJT_MGTDEVICE */ }; static const int npagers = sizeof(pagertab) / sizeof(pagertab[0]); /* * Kernel address space for mapping pages. * Used by pagers where KVAs are needed for IO. * * XXX needs to be large enough to support the number of pending async * cleaning requests (NPENDINGIO == 64) * the maximum swap cluster size * (MAXPHYS == 64k) if you want to get the most efficiency. */ struct mtx_padalign pbuf_mtx; static TAILQ_HEAD(swqueue, buf) bswlist; static int bswneeded; vm_offset_t swapbkva; /* swap buffers kva */ void vm_pager_init() { struct pagerops **pgops; TAILQ_INIT(&bswlist); /* * Initialize known pagers */ for (pgops = pagertab; pgops < &pagertab[npagers]; pgops++) if ((*pgops)->pgo_init != NULL) (*(*pgops)->pgo_init) (); } void vm_pager_bufferinit() { struct buf *bp; int i; mtx_init(&pbuf_mtx, "pbuf mutex", NULL, MTX_DEF); bp = swbuf; /* * Now set up swap and physical I/O buffer headers. */ for (i = 0; i < nswbuf; i++, bp++) { TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist); BUF_LOCKINIT(bp); LIST_INIT(&bp->b_dep); bp->b_rcred = bp->b_wcred = NOCRED; bp->b_xflags = 0; } cluster_pbuf_freecnt = nswbuf / 2; vnode_pbuf_freecnt = nswbuf / 2 + 1; vnode_async_pbuf_freecnt = nswbuf / 2; } /* * Allocate an instance of a pager of the given type. * Size, protection and offset parameters are passed in for pagers that * need to perform page-level validation (e.g. the device pager). */ vm_object_t vm_pager_allocate(objtype_t type, void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t off, struct ucred *cred) { vm_object_t ret; struct pagerops *ops; ops = pagertab[type]; if (ops) ret = (*ops->pgo_alloc) (handle, size, prot, off, cred); else ret = NULL; return (ret); } /* * The object must be locked. */ void vm_pager_deallocate(object) vm_object_t object; { VM_OBJECT_ASSERT_WLOCKED(object); (*pagertab[object->type]->pgo_dealloc) (object); } /* * vm_pager_get_pages() - inline, see vm/vm_pager.h * vm_pager_put_pages() - inline, see vm/vm_pager.h * vm_pager_has_page() - inline, see vm/vm_pager.h */ /* * Search the specified pager object list for an object with the * specified handle. If an object with the specified handle is found, * increase its reference count and return it. Otherwise, return NULL. * * The pager object list must be locked. */ vm_object_t vm_pager_object_lookup(struct pagerlst *pg_list, void *handle) { vm_object_t object; TAILQ_FOREACH(object, pg_list, pager_object_list) { if (object->handle == handle) { VM_OBJECT_WLOCK(object); if ((object->flags & OBJ_DEAD) == 0) { vm_object_reference_locked(object); VM_OBJECT_WUNLOCK(object); break; } VM_OBJECT_WUNLOCK(object); } } return (object); } /* - * Free the non-requested pages from the given array. + * Free the non-requested pages from the given array. To remove all pages, + * caller should provide out of range reqpage number. */ void vm_pager_free_nonreq(vm_object_t object, vm_page_t ma[], int reqpage, - int npages) + int npages, boolean_t object_locked) { + enum { UNLOCKED, CALLER_LOCKED, INTERNALLY_LOCKED } locked; int i; - boolean_t object_locked; - VM_OBJECT_ASSERT_UNLOCKED(object); - object_locked = FALSE; + if (object_locked) { + VM_OBJECT_ASSERT_WLOCKED(object); + locked = CALLER_LOCKED; + } else { + VM_OBJECT_ASSERT_UNLOCKED(object); + locked = UNLOCKED; + } for (i = 0; i < npages; ++i) { if (i != reqpage) { - if (!object_locked) { + if (locked == UNLOCKED) { VM_OBJECT_WLOCK(object); - object_locked = TRUE; + locked = INTERNALLY_LOCKED; } vm_page_lock(ma[i]); vm_page_free(ma[i]); vm_page_unlock(ma[i]); } } - if (object_locked) + if (locked == INTERNALLY_LOCKED) VM_OBJECT_WUNLOCK(object); } /* * initialize a physical buffer */ /* * XXX This probably belongs in vfs_bio.c */ static void initpbuf(struct buf *bp) { KASSERT(bp->b_bufobj == NULL, ("initpbuf with bufobj")); KASSERT(bp->b_vp == NULL, ("initpbuf with vp")); bp->b_rcred = NOCRED; bp->b_wcred = NOCRED; bp->b_qindex = 0; /* On no queue (QUEUE_NONE) */ bp->b_saveaddr = (caddr_t) (MAXPHYS * (bp - swbuf)) + swapbkva; bp->b_data = bp->b_saveaddr; bp->b_kvabase = bp->b_saveaddr; bp->b_kvasize = MAXPHYS; bp->b_xflags = 0; bp->b_flags = 0; bp->b_ioflags = 0; bp->b_iodone = NULL; bp->b_error = 0; BUF_LOCK(bp, LK_EXCLUSIVE, NULL); } /* * allocate a physical buffer * * There are a limited number (nswbuf) of physical buffers. We need * to make sure that no single subsystem is able to hog all of them, * so each subsystem implements a counter which is typically initialized * to 1/2 nswbuf. getpbuf() decrements this counter in allocation and * increments it on release, and blocks if the counter hits zero. A * subsystem may initialize the counter to -1 to disable the feature, * but it must still be sure to match up all uses of getpbuf() with * relpbuf() using the same variable. * * NOTE: pfreecnt can be NULL, but this 'feature' will be removed * relatively soon when the rest of the subsystems get smart about it. XXX */ struct buf * getpbuf(int *pfreecnt) { struct buf *bp; mtx_lock(&pbuf_mtx); for (;;) { if (pfreecnt) { while (*pfreecnt == 0) { msleep(pfreecnt, &pbuf_mtx, PVM, "wswbuf0", 0); } } /* get a bp from the swap buffer header pool */ if ((bp = TAILQ_FIRST(&bswlist)) != NULL) break; bswneeded = 1; msleep(&bswneeded, &pbuf_mtx, PVM, "wswbuf1", 0); /* loop in case someone else grabbed one */ } TAILQ_REMOVE(&bswlist, bp, b_freelist); if (pfreecnt) --*pfreecnt; mtx_unlock(&pbuf_mtx); initpbuf(bp); return bp; } /* * allocate a physical buffer, if one is available. * * Note that there is no NULL hack here - all subsystems using this * call understand how to use pfreecnt. */ struct buf * trypbuf(int *pfreecnt) { struct buf *bp; mtx_lock(&pbuf_mtx); if (*pfreecnt == 0 || (bp = TAILQ_FIRST(&bswlist)) == NULL) { mtx_unlock(&pbuf_mtx); return NULL; } TAILQ_REMOVE(&bswlist, bp, b_freelist); --*pfreecnt; mtx_unlock(&pbuf_mtx); initpbuf(bp); return bp; } /* * release a physical buffer * * NOTE: pfreecnt can be NULL, but this 'feature' will be removed * relatively soon when the rest of the subsystems get smart about it. XXX */ void relpbuf(struct buf *bp, int *pfreecnt) { if (bp->b_rcred != NOCRED) { crfree(bp->b_rcred); bp->b_rcred = NOCRED; } if (bp->b_wcred != NOCRED) { crfree(bp->b_wcred); bp->b_wcred = NOCRED; } KASSERT(bp->b_vp == NULL, ("relpbuf with vp")); KASSERT(bp->b_bufobj == NULL, ("relpbuf with bufobj")); BUF_UNLOCK(bp); mtx_lock(&pbuf_mtx); TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist); if (bswneeded) { bswneeded = 0; wakeup(&bswneeded); } if (pfreecnt) { if (++*pfreecnt == 1) wakeup(pfreecnt); } mtx_unlock(&pbuf_mtx); } /* * Associate a p-buffer with a vnode. * * Also sets B_PAGING flag to indicate that vnode is not fully associated * with the buffer. i.e. the bp has not been linked into the vnode or * ref-counted. */ void pbgetvp(struct vnode *vp, struct buf *bp) { KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); KASSERT(bp->b_bufobj == NULL, ("pbgetvp: not free (bufobj)")); bp->b_vp = vp; bp->b_flags |= B_PAGING; bp->b_bufobj = &vp->v_bufobj; } /* * Associate a p-buffer with a vnode. * * Also sets B_PAGING flag to indicate that vnode is not fully associated * with the buffer. i.e. the bp has not been linked into the vnode or * ref-counted. */ void pbgetbo(struct bufobj *bo, struct buf *bp) { KASSERT(bp->b_vp == NULL, ("pbgetbo: not free (vnode)")); KASSERT(bp->b_bufobj == NULL, ("pbgetbo: not free (bufobj)")); bp->b_flags |= B_PAGING; bp->b_bufobj = bo; } /* * Disassociate a p-buffer from a vnode. */ void pbrelvp(struct buf *bp) { KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); KASSERT(bp->b_bufobj != NULL, ("pbrelvp: NULL bufobj")); KASSERT((bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) == 0, ("pbrelvp: pager buf on vnode list.")); bp->b_vp = NULL; bp->b_bufobj = NULL; bp->b_flags &= ~B_PAGING; } /* * Disassociate a p-buffer from a bufobj. */ void pbrelbo(struct buf *bp) { KASSERT(bp->b_vp == NULL, ("pbrelbo: vnode")); KASSERT(bp->b_bufobj != NULL, ("pbrelbo: NULL bufobj")); KASSERT((bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) == 0, ("pbrelbo: pager buf on vnode list.")); bp->b_bufobj = NULL; bp->b_flags &= ~B_PAGING; } Index: head/sys/vm/vm_pager.h =================================================================== --- head/sys/vm/vm_pager.h (revision 280188) +++ head/sys/vm/vm_pager.h (revision 280189) @@ -1,228 +1,228 @@ /*- * Copyright (c) 1990 University of Utah. * 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 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. * 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. * * @(#)vm_pager.h 8.4 (Berkeley) 1/12/94 * $FreeBSD$ */ /* * Pager routine interface definition. */ #ifndef _VM_PAGER_ #define _VM_PAGER_ #include TAILQ_HEAD(pagerlst, vm_object); typedef void pgo_init_t(void); typedef vm_object_t pgo_alloc_t(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); typedef void pgo_dealloc_t(vm_object_t); typedef int pgo_getpages_t(vm_object_t, vm_page_t *, int, int); typedef void pgo_getpages_iodone_t(void *, vm_page_t *, int, int); typedef int pgo_getpages_async_t(vm_object_t, vm_page_t *, int, int, pgo_getpages_iodone_t, void *); typedef void pgo_putpages_t(vm_object_t, vm_page_t *, int, int, int *); typedef boolean_t pgo_haspage_t(vm_object_t, vm_pindex_t, int *, int *); typedef void pgo_pageunswapped_t(vm_page_t); struct pagerops { pgo_init_t *pgo_init; /* Initialize pager. */ pgo_alloc_t *pgo_alloc; /* Allocate pager. */ pgo_dealloc_t *pgo_dealloc; /* Disassociate. */ pgo_getpages_t *pgo_getpages; /* Get (read) page. */ pgo_getpages_async_t *pgo_getpages_async; /* Get page asyncly. */ pgo_putpages_t *pgo_putpages; /* Put (write) page. */ pgo_haspage_t *pgo_haspage; /* Query page. */ pgo_pageunswapped_t *pgo_pageunswapped; }; extern struct pagerops defaultpagerops; extern struct pagerops swappagerops; extern struct pagerops vnodepagerops; extern struct pagerops devicepagerops; extern struct pagerops physpagerops; extern struct pagerops sgpagerops; extern struct pagerops mgtdevicepagerops; /* * get/put return values * OK operation was successful * BAD specified data was out of the accepted range * FAIL specified data was in range, but doesn't exist * PEND operations was initiated but not completed * ERROR error while accessing data that is in range and exists * AGAIN temporary resource shortage prevented operation from happening */ #define VM_PAGER_OK 0 #define VM_PAGER_BAD 1 #define VM_PAGER_FAIL 2 #define VM_PAGER_PEND 3 #define VM_PAGER_ERROR 4 #define VM_PAGER_AGAIN 5 #define VM_PAGER_PUT_SYNC 0x0001 #define VM_PAGER_PUT_INVAL 0x0002 #define VM_PAGER_CLUSTER_OK 0x0008 #ifdef _KERNEL extern struct pagerops *pagertab[]; extern struct mtx_padalign pbuf_mtx; vm_object_t vm_pager_allocate(objtype_t, void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); void vm_pager_bufferinit(void); void vm_pager_deallocate(vm_object_t); static __inline int vm_pager_get_pages(vm_object_t, vm_page_t *, int, int); static inline int vm_pager_get_pages_async(vm_object_t, vm_page_t *, int, int, pgo_getpages_iodone_t, void *); static __inline boolean_t vm_pager_has_page(vm_object_t, vm_pindex_t, int *, int *); void vm_pager_init(void); vm_object_t vm_pager_object_lookup(struct pagerlst *, void *); void vm_pager_free_nonreq(vm_object_t object, vm_page_t ma[], int reqpage, - int npages); + int npages, boolean_t object_locked); /* * vm_page_get_pages: * * Retrieve pages from the VM system in order to map them into an object * ( or into VM space somewhere ). If the pagein was successful, we * must fully validate it. */ static __inline int vm_pager_get_pages( vm_object_t object, vm_page_t *m, int count, int reqpage ) { int r; VM_OBJECT_ASSERT_WLOCKED(object); r = (*pagertab[object->type]->pgo_getpages)(object, m, count, reqpage); if (r == VM_PAGER_OK && m[reqpage]->valid != VM_PAGE_BITS_ALL) { vm_page_zero_invalid(m[reqpage], TRUE); } return (r); } static inline int vm_pager_get_pages_async(vm_object_t object, vm_page_t *m, int count, int reqpage, pgo_getpages_iodone_t iodone, void *arg) { VM_OBJECT_ASSERT_WLOCKED(object); return ((*pagertab[object->type]->pgo_getpages_async)(object, m, count, reqpage, iodone, arg)); } static __inline void vm_pager_put_pages( vm_object_t object, vm_page_t *m, int count, int flags, int *rtvals ) { VM_OBJECT_ASSERT_WLOCKED(object); (*pagertab[object->type]->pgo_putpages) (object, m, count, flags, rtvals); } /* * vm_pager_haspage * * Check to see if an object's pager has the requested page. The * object's pager will also set before and after to give the caller * some idea of the number of pages before and after the requested * page can be I/O'd efficiently. * * The object must be locked. */ static __inline boolean_t vm_pager_has_page( vm_object_t object, vm_pindex_t offset, int *before, int *after ) { boolean_t ret; VM_OBJECT_ASSERT_WLOCKED(object); ret = (*pagertab[object->type]->pgo_haspage) (object, offset, before, after); return (ret); } /* * vm_pager_page_unswapped * * Destroy swap associated with the page. * * The object containing the page must be locked. * This function may not block. * * XXX: A much better name would be "vm_pager_page_dirtied()" * XXX: It is not obvious if this could be profitably used by any * XXX: pagers besides the swap_pager or if it should even be a * XXX: generic pager_op in the first place. */ static __inline void vm_pager_page_unswapped(vm_page_t m) { VM_OBJECT_ASSERT_LOCKED(m->object); if (pagertab[m->object->type]->pgo_pageunswapped) (*pagertab[m->object->type]->pgo_pageunswapped)(m); } struct cdev_pager_ops { int (*cdev_pg_fault)(vm_object_t vm_obj, vm_ooffset_t offset, int prot, vm_page_t *mres); int (*cdev_pg_ctor)(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred, u_short *color); void (*cdev_pg_dtor)(void *handle); }; vm_object_t cdev_pager_allocate(void *handle, enum obj_type tp, struct cdev_pager_ops *ops, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred); vm_object_t cdev_pager_lookup(void *handle); void cdev_pager_free_page(vm_object_t object, vm_page_t m); #endif /* _KERNEL */ #endif /* _VM_PAGER_ */ Index: head/sys/vm/vnode_pager.c =================================================================== --- head/sys/vm/vnode_pager.c (revision 280188) +++ head/sys/vm/vnode_pager.c (revision 280189) @@ -1,1386 +1,1376 @@ /*- * 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 #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_local_getpages0(struct vnode *, vm_page_t *, int, int, vop_getpages_iodone_t, void *); static int vnode_pager_getpages(vm_object_t, vm_page_t *, int, int); static int vnode_pager_getpages_async(vm_object_t, vm_page_t *, int, int, vop_getpages_iodone_t, void *); static void vnode_pager_putpages(vm_object_t, vm_page_t *, int, int, 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); static int vnode_pager_generic_getpages_done(struct buf *); static void vnode_pager_generic_getpages_done_async(struct buf *); struct pagerops vnodepagerops = { .pgo_alloc = vnode_pager_alloc, .pgo_dealloc = vnode_pager_dealloc, .pgo_getpages = vnode_pager_getpages, .pgo_getpages_async = vnode_pager_getpages_async, .pgo_putpages = vnode_pager_putpages, .pgo_haspage = vnode_pager_haspage, }; int vnode_pbuf_freecnt; int vnode_async_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_WLOCK(object); if (!(object->flags & OBJ_DEAD)) { VM_OBJECT_WUNLOCK(object); return (0); } VOP_UNLOCK(vp, 0); vm_object_set_flag(object, OBJ_DISCONNECTWNT); VM_OBJECT_SLEEP(object, 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_WLOCK(object); object->ref_count--; VM_OBJECT_WUNLOCK(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_WLOCK(obj); if (obj->ref_count == 0) { /* * don't double-terminate the object */ if ((obj->flags & OBJ_DEAD) == 0) vm_object_terminate(obj); else VM_OBJECT_WUNLOCK(obj); } else { /* * Woe to the process that tries to page now :-). */ vm_pager_deallocate(obj); VM_OBJECT_WUNLOCK(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_WLOCK(object); if ((object->flags & OBJ_DEAD) == 0) break; vm_object_set_flag(object, OBJ_DISCONNECTWNT); VM_OBJECT_SLEEP(object, object, PDROP | PVM, "vadead", 0); } KASSERT(vp->v_usecount != 0, ("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_WUNLOCK(object); } vref(vp); return (object); } /* * The object must be locked. */ static void vnode_pager_dealloc(vm_object_t object) { struct vnode *vp; int refs; vp = object->handle; if (vp == NULL) panic("vnode_pager_dealloc: pager already dealloced"); VM_OBJECT_ASSERT_WLOCKED(object); 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_WUNLOCK(object); while (refs-- > 0) vunref(vp); VM_OBJECT_WLOCK(object); } static boolean_t vnode_pager_haspage(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_ASSERT_WLOCKED(object); /* * 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_WUNLOCK(object); err = VOP_BMAP(vp, reqblock, NULL, &bn, after, before); VM_OBJECT_WLOCK(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(struct vnode *vp, vm_ooffset_t nsize) { vm_object_t object; 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_WLOCK(object); if (object->type == OBJT_DEAD) { VM_OBJECT_WUNLOCK(object); return; } KASSERT(object->type == OBJT_VNODE, ("not vnode-backed object %p", object)); if (nsize == object->un_pager.vnp.vnp_size) { /* * Hasn't changed size */ VM_OBJECT_WUNLOCK(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_page_lookup(object, OFF_TO_IDX(nsize))) != NULL && m->valid != 0) { int base = (int)nsize & PAGE_MASK; int size = PAGE_SIZE - base; /* * 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) && vm_page_is_cached(object, OFF_TO_IDX(nsize))) { vm_page_cache_free(object, OFF_TO_IDX(nsize), nobjsize); } } object->un_pager.vnp.vnp_size = nsize; object->size = nobjsize; VM_OBJECT_WUNLOCK(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(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_WLOCK(object); m->valid |= bits; VM_OBJECT_WUNLOCK(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(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_ASSERT_WLOCKED(object); 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_WUNLOCK(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_WLOCK(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(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_WUNLOCK(object); rtval = VOP_GETPAGES(vp, m, bytes, reqpage); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: FS getpages not implemented\n")); VM_OBJECT_WLOCK(object); return rtval; } static int vnode_pager_getpages_async(vm_object_t object, vm_page_t *m, int count, int reqpage, vop_getpages_iodone_t iodone, void *arg) { struct vnode *vp; int rtval; vp = object->handle; VM_OBJECT_WUNLOCK(object); rtval = VOP_GETPAGES_ASYNC(vp, m, count * PAGE_SIZE, reqpage, 0, iodone, arg); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: FS getpages_async not implemented\n")); VM_OBJECT_WLOCK(object); return (rtval); } /* * The implementation of VOP_GETPAGES() and VOP_GETPAGES_ASYNC() for * local filesystems, where partially valid pages can only occur at * the end of file. */ int vnode_pager_local_getpages(struct vop_getpages_args *ap) { return (vnode_pager_local_getpages0(ap->a_vp, ap->a_m, ap->a_count, ap->a_reqpage, NULL, NULL)); } int vnode_pager_local_getpages_async(struct vop_getpages_async_args *ap) { return (vnode_pager_local_getpages0(ap->a_vp, ap->a_m, ap->a_count, ap->a_reqpage, ap->a_iodone, ap->a_arg)); } static int vnode_pager_local_getpages0(struct vnode *vp, vm_page_t *m, int bytecount, int reqpage, vop_getpages_iodone_t iodone, void *arg) { vm_page_t mreq; mreq = m[reqpage]; /* * Since the caller has busied the requested page, that page's valid * field will not be changed by other threads. */ vm_page_assert_xbusied(mreq); /* * The requested page has valid blocks. Invalid part can only * exist at the end of file, and the page is made fully valid * by zeroing in vm_pager_get_pages(). Free non-requested * pages, since no i/o is done to read its content. */ if (mreq->valid != 0) { vm_pager_free_nonreq(mreq->object, m, reqpage, - round_page(bytecount) / PAGE_SIZE); + round_page(bytecount) / PAGE_SIZE, FALSE); if (iodone != NULL) iodone(arg, m, reqpage, 0); return (VM_PAGER_OK); } return (vnode_pager_generic_getpages(vp, m, bytecount, reqpage, iodone, arg)); } /* * 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(struct vnode *vp, vm_page_t *m, int bytecount, int reqpage, vop_getpages_iodone_t iodone, void *arg) { vm_object_t object; off_t foff; int i, j, size, bsize, first, *freecnt; 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; foff = IDX_TO_OFF(m[reqpage]->pindex); /* * Synchronous and asynchronous paging operations use different * free pbuf counters. This is done to avoid asynchronous requests * to consume all pbufs. * Allocate the pbuf at the very beginning of the function, so that * if we are low on certain kind of pbufs don't even proceed to BMAP, * but sleep. */ freecnt = iodone != NULL ? &vnode_async_pbuf_freecnt : &vnode_pbuf_freecnt; bp = getpbuf(freecnt); /* * Get the underlying device blocks for the file with VOP_BMAP(). * If the file system doesn't support VOP_BMAP, use old way of * getting pages via VOP_READ. */ error = VOP_BMAP(vp, foff / bsize, &bo, &reqblock, NULL, NULL); if (error == EOPNOTSUPP) { relpbuf(bp, freecnt); VM_OBJECT_WLOCK(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_WUNLOCK(object); return (error); } else if (error != 0) { relpbuf(bp, freecnt); - vm_pager_free_nonreq(object, m, reqpage, count); + vm_pager_free_nonreq(object, m, reqpage, count, FALSE); 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)) { relpbuf(bp, freecnt); - vm_pager_free_nonreq(object, m, reqpage, count); + vm_pager_free_nonreq(object, m, reqpage, count, FALSE); PCPU_INC(cnt.v_vnodein); PCPU_INC(cnt.v_vnodepgsin); return vnode_pager_input_smlfs(object, m[reqpage]); } /* * Since the caller has busied the requested page, that page's valid * field will not be changed by other threads. */ vm_page_assert_xbusied(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. */ if (m[reqpage]->valid == VM_PAGE_BITS_ALL) { relpbuf(bp, freecnt); - vm_pager_free_nonreq(object, m, reqpage, count); + vm_pager_free_nonreq(object, m, reqpage, count, FALSE); return (VM_PAGER_OK); } else if (reqblock == -1) { relpbuf(bp, freecnt); pmap_zero_page(m[reqpage]); KASSERT(m[reqpage]->dirty == 0, ("vnode_pager_generic_getpages: page %p is dirty", m)); VM_OBJECT_WLOCK(object); 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_pager_free_nonreq(object, m, reqpage, count, TRUE); VM_OBJECT_WUNLOCK(object); return (VM_PAGER_OK); } else if (m[reqpage]->valid != 0) { VM_OBJECT_WLOCK(object); m[reqpage]->valid = 0; VM_OBJECT_WUNLOCK(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) { relpbuf(bp, freecnt); - VM_OBJECT_WLOCK(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_WUNLOCK(object); + /* The requested page may be out of range. */ + vm_pager_free_nonreq(object, m + i, reqpage - i, + count - i, FALSE); return (VM_PAGER_ERROR); } if (firstaddr == -1) { VM_OBJECT_WLOCK(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_WUNLOCK(object); runend = i + 1; first = runend; continue; } runend = i + runpg; if (runend <= reqpage) { VM_OBJECT_WLOCK(object); for (j = i; j < runend; j++) { vm_page_lock(m[j]); vm_page_free(m[j]); vm_page_unlock(m[j]); } VM_OBJECT_WUNLOCK(object); } else { if (runpg < (count - first)) { VM_OBJECT_WLOCK(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_WUNLOCK(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->b_kvaalloc = bp->b_data; /* * and map the pages to be read into the kva, if the filesystem * requires mapped buffers. */ if ((vp->v_mount->mnt_kern_flag & MNTK_UNMAPPED_BUFS) != 0 && unmapped_buf_allowed) { bp->b_data = unmapped_buf; bp->b_kvabase = unmapped_buf; bp->b_offset = 0; bp->b_flags |= B_UNMAPPED; } else pmap_qenter((vm_offset_t)bp->b_kvaalloc, m, count); /* build a minimal buffer header */ bp->b_iocmd = BIO_READ; 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; for (i = 0; i < count; i++) bp->b_pages[i] = m[i]; bp->b_npages = count; bp->b_pager.pg_reqpage = reqpage; 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); if (iodone != NULL) { /* async */ bp->b_pager.pg_iodone = iodone; bp->b_caller1 = arg; bp->b_iodone = vnode_pager_generic_getpages_done_async; bp->b_flags |= B_ASYNC; BUF_KERNPROC(bp); bstrategy(bp); /* Good bye! */ } else { bp->b_iodone = bdone; bstrategy(bp); bwait(bp, PVM, "vnread"); error = vnode_pager_generic_getpages_done(bp); for (i = 0; i < bp->b_npages; i++) bp->b_pages[i] = NULL; bp->b_vp = NULL; pbrelbo(bp); relpbuf(bp, &vnode_pbuf_freecnt); } return (error != 0 ? VM_PAGER_ERROR : VM_PAGER_OK); } static void vnode_pager_generic_getpages_done_async(struct buf *bp) { int error; error = vnode_pager_generic_getpages_done(bp); bp->b_pager.pg_iodone(bp->b_caller1, bp->b_pages, bp->b_pager.pg_reqpage, error); for (int i = 0; i < bp->b_npages; i++) bp->b_pages[i] = NULL; bp->b_vp = NULL; pbrelbo(bp); relpbuf(bp, &vnode_async_pbuf_freecnt); } static int vnode_pager_generic_getpages_done(struct buf *bp) { vm_object_t object; off_t tfoff, nextoff; int i, error; error = (bp->b_ioflags & BIO_ERROR) != 0 ? EIO : 0; object = bp->b_vp->v_object; if (error == 0 && bp->b_bcount != bp->b_npages * PAGE_SIZE) { if ((bp->b_flags & B_UNMAPPED) != 0) { bp->b_flags &= ~B_UNMAPPED; pmap_qenter((vm_offset_t)bp->b_kvaalloc, bp->b_pages, bp->b_npages); } bzero(bp->b_kvaalloc + bp->b_bcount, PAGE_SIZE * bp->b_npages - bp->b_bcount); } if ((bp->b_flags & B_UNMAPPED) == 0) pmap_qremove((vm_offset_t)bp->b_kvaalloc, bp->b_npages); if ((bp->b_vp->v_mount->mnt_kern_flag & MNTK_UNMAPPED_BUFS) != 0) { bp->b_data = bp->b_kvaalloc; bp->b_kvabase = bp->b_kvaalloc; bp->b_flags &= ~B_UNMAPPED; } VM_OBJECT_WLOCK(object); for (i = 0, tfoff = IDX_TO_OFF(bp->b_pages[0]->pindex); i < bp->b_npages; i++, tfoff = nextoff) { vm_page_t mt; nextoff = tfoff + PAGE_SIZE; mt = bp->b_pages[i]; if (nextoff <= object->un_pager.vnp.vnp_size) { /* * Read filled up entire page. */ mt->valid = VM_PAGE_BITS_ALL; KASSERT(mt->dirty == 0, ("%s: page %p is dirty", __func__, mt)); KASSERT(!pmap_page_is_mapped(mt), ("%s: page %p is mapped", __func__, 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, ("%s: page %p is dirty", __func__, mt)); } if (i != bp->b_pager.pg_reqpage) vm_page_readahead_finish(mt); } VM_OBJECT_WUNLOCK(object); if (error != 0) printf("%s: I/O read error %d\n", __func__, error); return (error); } /* * 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(vm_object_t object, vm_page_t *m, int count, int flags, 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 (vm_cnt.v_free_count + vm_cnt.v_cache_count < vm_cnt.v_pageout_free_min) flags |= VM_PAGER_PUT_SYNC; /* * Call device-specific putpages function */ vp = object->handle; VM_OBJECT_WUNLOCK(object); rtval = VOP_PUTPAGES(vp, m, bytes, flags, rtvals); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: stale FS putpages\n")); VM_OBJECT_WLOCK(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_WLOCK(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]; vm_page_assert_sbusied(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_WUNLOCK(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_WLOCK(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_WUNLOCK(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_WLOCK(object); if (object->type != OBJT_VNODE) { VM_OBJECT_WUNLOCK(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_WUNLOCK(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_WLOCK(object); /* * First, recheck the object type to account for the race when * the vnode is reclaimed. */ if (object->type != OBJT_VNODE) { VM_OBJECT_WUNLOCK(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_WUNLOCK(object); return; } vp = object->handle; vhold(vp); VM_OBJECT_WUNLOCK(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); }