Index: head/sys/kern/kern_exec.c =================================================================== --- head/sys/kern/kern_exec.c (revision 280326) +++ head/sys/kern/kern_exec.c (revision 280327) @@ -1,1501 +1,1498 @@ /*- * Copyright (c) 1993, David Greenman * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include "opt_capsicum.h" #include "opt_hwpmc_hooks.h" #include "opt_ktrace.h" #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #include #include #include #include #include #include #include #include #include #ifdef HWPMC_HOOKS #include #endif #include #include #include #ifdef KDTRACE_HOOKS #include dtrace_execexit_func_t dtrace_fasttrap_exec; #endif SDT_PROVIDER_DECLARE(proc); SDT_PROBE_DEFINE1(proc, kernel, , exec, "char *"); SDT_PROBE_DEFINE1(proc, kernel, , exec__failure, "int"); SDT_PROBE_DEFINE1(proc, kernel, , exec__success, "char *"); MALLOC_DEFINE(M_PARGS, "proc-args", "Process arguments"); static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS); static int sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS); static int sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS); static int do_execve(struct thread *td, struct image_args *args, struct mac *mac_p); /* XXX This should be vm_size_t. */ SYSCTL_PROC(_kern, KERN_PS_STRINGS, ps_strings, CTLTYPE_ULONG|CTLFLAG_RD, NULL, 0, sysctl_kern_ps_strings, "LU", ""); /* XXX This should be vm_size_t. */ SYSCTL_PROC(_kern, KERN_USRSTACK, usrstack, CTLTYPE_ULONG|CTLFLAG_RD| CTLFLAG_CAPRD, NULL, 0, sysctl_kern_usrstack, "LU", ""); SYSCTL_PROC(_kern, OID_AUTO, stackprot, CTLTYPE_INT|CTLFLAG_RD, NULL, 0, sysctl_kern_stackprot, "I", ""); u_long ps_arg_cache_limit = PAGE_SIZE / 16; SYSCTL_ULONG(_kern, OID_AUTO, ps_arg_cache_limit, CTLFLAG_RW, &ps_arg_cache_limit, 0, ""); static int disallow_high_osrel; SYSCTL_INT(_kern, OID_AUTO, disallow_high_osrel, CTLFLAG_RW, &disallow_high_osrel, 0, "Disallow execution of binaries built for higher version of the world"); static int map_at_zero = 0; SYSCTL_INT(_security_bsd, OID_AUTO, map_at_zero, CTLFLAG_RWTUN, &map_at_zero, 0, "Permit processes to map an object at virtual address 0."); static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS) { struct proc *p; int error; p = curproc; #ifdef SCTL_MASK32 if (req->flags & SCTL_MASK32) { unsigned int val; val = (unsigned int)p->p_sysent->sv_psstrings; error = SYSCTL_OUT(req, &val, sizeof(val)); } else #endif error = SYSCTL_OUT(req, &p->p_sysent->sv_psstrings, sizeof(p->p_sysent->sv_psstrings)); return error; } static int sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS) { struct proc *p; int error; p = curproc; #ifdef SCTL_MASK32 if (req->flags & SCTL_MASK32) { unsigned int val; val = (unsigned int)p->p_sysent->sv_usrstack; error = SYSCTL_OUT(req, &val, sizeof(val)); } else #endif error = SYSCTL_OUT(req, &p->p_sysent->sv_usrstack, sizeof(p->p_sysent->sv_usrstack)); return error; } static int sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS) { struct proc *p; p = curproc; return (SYSCTL_OUT(req, &p->p_sysent->sv_stackprot, sizeof(p->p_sysent->sv_stackprot))); } /* * Each of the items is a pointer to a `const struct execsw', hence the * double pointer here. */ static const struct execsw **execsw; #ifndef _SYS_SYSPROTO_H_ struct execve_args { char *fname; char **argv; char **envv; }; #endif int sys_execve(td, uap) struct thread *td; struct execve_args /* { char *fname; char **argv; char **envv; } */ *uap; { int error; struct image_args args; error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE, uap->argv, uap->envv); if (error == 0) error = kern_execve(td, &args, NULL); return (error); } #ifndef _SYS_SYSPROTO_H_ struct fexecve_args { int fd; char **argv; char **envv; } #endif int sys_fexecve(struct thread *td, struct fexecve_args *uap) { int error; struct image_args args; error = exec_copyin_args(&args, NULL, UIO_SYSSPACE, uap->argv, uap->envv); if (error == 0) { args.fd = uap->fd; error = kern_execve(td, &args, NULL); } return (error); } #ifndef _SYS_SYSPROTO_H_ struct __mac_execve_args { char *fname; char **argv; char **envv; struct mac *mac_p; }; #endif int sys___mac_execve(td, uap) struct thread *td; struct __mac_execve_args /* { char *fname; char **argv; char **envv; struct mac *mac_p; } */ *uap; { #ifdef MAC int error; struct image_args args; error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE, uap->argv, uap->envv); if (error == 0) error = kern_execve(td, &args, uap->mac_p); return (error); #else return (ENOSYS); #endif } /* * XXX: kern_execve has the astonishing property of not always returning to * the caller. If sufficiently bad things happen during the call to * do_execve(), it can end up calling exit1(); as a result, callers must * avoid doing anything which they might need to undo (e.g., allocating * memory). */ int kern_execve(td, args, mac_p) struct thread *td; struct image_args *args; struct mac *mac_p; { struct proc *p = td->td_proc; struct vmspace *oldvmspace; int error; AUDIT_ARG_ARGV(args->begin_argv, args->argc, args->begin_envv - args->begin_argv); AUDIT_ARG_ENVV(args->begin_envv, args->envc, args->endp - args->begin_envv); if (p->p_flag & P_HADTHREADS) { PROC_LOCK(p); if (thread_single(p, SINGLE_BOUNDARY)) { PROC_UNLOCK(p); exec_free_args(args); return (ERESTART); /* Try again later. */ } PROC_UNLOCK(p); } KASSERT((td->td_pflags & TDP_EXECVMSPC) == 0, ("nested execve")); oldvmspace = td->td_proc->p_vmspace; error = do_execve(td, args, mac_p); if (p->p_flag & P_HADTHREADS) { PROC_LOCK(p); /* * If success, we upgrade to SINGLE_EXIT state to * force other threads to suicide. */ if (error == 0) thread_single(p, SINGLE_EXIT); else thread_single_end(p, SINGLE_BOUNDARY); PROC_UNLOCK(p); } if ((td->td_pflags & TDP_EXECVMSPC) != 0) { KASSERT(td->td_proc->p_vmspace != oldvmspace, ("oldvmspace still used")); vmspace_free(oldvmspace); td->td_pflags &= ~TDP_EXECVMSPC; } return (error); } /* * In-kernel implementation of execve(). All arguments are assumed to be * userspace pointers from the passed thread. */ static int do_execve(td, args, mac_p) struct thread *td; struct image_args *args; struct mac *mac_p; { struct proc *p = td->td_proc; struct nameidata nd; struct ucred *newcred = NULL, *oldcred; struct uidinfo *euip = NULL; register_t *stack_base; int error, i; struct image_params image_params, *imgp; struct vattr attr; int (*img_first)(struct image_params *); struct pargs *oldargs = NULL, *newargs = NULL; struct sigacts *oldsigacts, *newsigacts; #ifdef KTRACE struct vnode *tracevp = NULL; struct ucred *tracecred = NULL; #endif struct vnode *textvp = NULL, *binvp; cap_rights_t rights; int credential_changing; int textset; #ifdef MAC struct label *interpvplabel = NULL; int will_transition; #endif #ifdef HWPMC_HOOKS struct pmckern_procexec pe; #endif static const char fexecv_proc_title[] = "(fexecv)"; imgp = &image_params; /* * Lock the process and set the P_INEXEC flag to indicate that * it should be left alone until we're done here. This is * necessary to avoid race conditions - e.g. in ptrace() - * that might allow a local user to illicitly obtain elevated * privileges. */ PROC_LOCK(p); KASSERT((p->p_flag & P_INEXEC) == 0, ("%s(): process already has P_INEXEC flag", __func__)); p->p_flag |= P_INEXEC; PROC_UNLOCK(p); /* * Initialize part of the common data */ bzero(imgp, sizeof(*imgp)); imgp->proc = p; imgp->attr = &attr; imgp->args = args; #ifdef MAC error = mac_execve_enter(imgp, mac_p); if (error) goto exec_fail; #endif /* * Translate the file name. namei() returns a vnode pointer * in ni_vp amoung other things. * * XXXAUDIT: It would be desirable to also audit the name of the * interpreter if this is an interpreted binary. */ if (args->fname != NULL) { NDINIT(&nd, LOOKUP, ISOPEN | LOCKLEAF | FOLLOW | SAVENAME | AUDITVNODE1, UIO_SYSSPACE, args->fname, td); } SDT_PROBE(proc, kernel, , exec, args->fname, 0, 0, 0, 0 ); interpret: if (args->fname != NULL) { #ifdef CAPABILITY_MODE /* * While capability mode can't reach this point via direct * path arguments to execve(), we also don't allow * interpreters to be used in capability mode (for now). * Catch indirect lookups and return a permissions error. */ if (IN_CAPABILITY_MODE(td)) { error = ECAPMODE; goto exec_fail; } #endif error = namei(&nd); if (error) goto exec_fail; binvp = nd.ni_vp; imgp->vp = binvp; } else { AUDIT_ARG_FD(args->fd); /* * Descriptors opened only with O_EXEC or O_RDONLY are allowed. */ error = fgetvp_exec(td, args->fd, cap_rights_init(&rights, CAP_FEXECVE), &binvp); if (error) goto exec_fail; vn_lock(binvp, LK_EXCLUSIVE | LK_RETRY); AUDIT_ARG_VNODE1(binvp); imgp->vp = binvp; } /* * Check file permissions (also 'opens' file) */ error = exec_check_permissions(imgp); if (error) goto exec_fail_dealloc; imgp->object = imgp->vp->v_object; if (imgp->object != NULL) vm_object_reference(imgp->object); /* * Set VV_TEXT now so no one can write to the executable while we're * activating it. * * Remember if this was set before and unset it in case this is not * actually an executable image. */ textset = VOP_IS_TEXT(imgp->vp); VOP_SET_TEXT(imgp->vp); error = exec_map_first_page(imgp); if (error) goto exec_fail_dealloc; imgp->proc->p_osrel = 0; /* * If the current process has a special image activator it * wants to try first, call it. For example, emulating shell * scripts differently. */ error = -1; if ((img_first = imgp->proc->p_sysent->sv_imgact_try) != NULL) error = img_first(imgp); /* * Loop through the list of image activators, calling each one. * An activator returns -1 if there is no match, 0 on success, * and an error otherwise. */ for (i = 0; error == -1 && execsw[i]; ++i) { if (execsw[i]->ex_imgact == NULL || execsw[i]->ex_imgact == img_first) { continue; } error = (*execsw[i]->ex_imgact)(imgp); } if (error) { if (error == -1) { if (textset == 0) VOP_UNSET_TEXT(imgp->vp); error = ENOEXEC; } goto exec_fail_dealloc; } /* * Special interpreter operation, cleanup and loop up to try to * activate the interpreter. */ if (imgp->interpreted) { exec_unmap_first_page(imgp); /* * VV_TEXT needs to be unset for scripts. There is a short * period before we determine that something is a script where * VV_TEXT will be set. The vnode lock is held over this * entire period so nothing should illegitimately be blocked. */ VOP_UNSET_TEXT(imgp->vp); /* free name buffer and old vnode */ if (args->fname != NULL) NDFREE(&nd, NDF_ONLY_PNBUF); #ifdef MAC mac_execve_interpreter_enter(binvp, &interpvplabel); #endif if (imgp->opened) { VOP_CLOSE(binvp, FREAD, td->td_ucred, td); imgp->opened = 0; } vput(binvp); vm_object_deallocate(imgp->object); imgp->object = NULL; /* set new name to that of the interpreter */ NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW | SAVENAME, UIO_SYSSPACE, imgp->interpreter_name, td); args->fname = imgp->interpreter_name; goto interpret; } /* * NB: We unlock the vnode here because it is believed that none * of the sv_copyout_strings/sv_fixup operations require the vnode. */ VOP_UNLOCK(imgp->vp, 0); /* * Do the best to calculate the full path to the image file. */ if (imgp->auxargs != NULL && ((args->fname != NULL && args->fname[0] == '/') || vn_fullpath(td, imgp->vp, &imgp->execpath, &imgp->freepath) != 0)) imgp->execpath = args->fname; if (disallow_high_osrel && P_OSREL_MAJOR(p->p_osrel) > P_OSREL_MAJOR(__FreeBSD_version)) { error = ENOEXEC; uprintf("Osrel %d for image %s too high\n", p->p_osrel, imgp->execpath != NULL ? imgp->execpath : ""); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); goto exec_fail_dealloc; } /* * Copy out strings (args and env) and initialize stack base */ if (p->p_sysent->sv_copyout_strings) stack_base = (*p->p_sysent->sv_copyout_strings)(imgp); else stack_base = exec_copyout_strings(imgp); /* * If custom stack fixup routine present for this process * let it do the stack setup. * Else stuff argument count as first item on stack */ if (p->p_sysent->sv_fixup != NULL) (*p->p_sysent->sv_fixup)(&stack_base, imgp); else suword(--stack_base, imgp->args->argc); /* * For security and other reasons, the file descriptor table cannot * be shared after an exec. */ fdunshare(td); /* close files on exec */ fdcloseexec(td); /* * Malloc things before we need locks. */ i = imgp->args->begin_envv - imgp->args->begin_argv; /* Cache arguments if they fit inside our allowance */ if (ps_arg_cache_limit >= i + sizeof(struct pargs)) { newargs = pargs_alloc(i); bcopy(imgp->args->begin_argv, newargs->ar_args, i); } vn_lock(imgp->vp, LK_SHARED | LK_RETRY); /* Get a reference to the vnode prior to locking the proc */ VREF(binvp); /* * For security and other reasons, signal handlers cannot * be shared after an exec. The new process gets a copy of the old * handlers. In execsigs(), the new process will have its signals * reset. */ if (sigacts_shared(p->p_sigacts)) { oldsigacts = p->p_sigacts; newsigacts = sigacts_alloc(); sigacts_copy(newsigacts, oldsigacts); } else { oldsigacts = NULL; newsigacts = NULL; /* satisfy gcc */ } PROC_LOCK(p); if (oldsigacts) p->p_sigacts = newsigacts; oldcred = p->p_ucred; /* Stop profiling */ stopprofclock(p); /* reset caught signals */ execsigs(p); /* name this process - nameiexec(p, ndp) */ bzero(p->p_comm, sizeof(p->p_comm)); if (args->fname) bcopy(nd.ni_cnd.cn_nameptr, p->p_comm, min(nd.ni_cnd.cn_namelen, MAXCOMLEN)); else if (vn_commname(binvp, p->p_comm, sizeof(p->p_comm)) != 0) bcopy(fexecv_proc_title, p->p_comm, sizeof(fexecv_proc_title)); bcopy(p->p_comm, td->td_name, sizeof(td->td_name)); #ifdef KTR sched_clear_tdname(td); #endif /* * mark as execed, wakeup the process that vforked (if any) and tell * it that it now has its own resources back */ p->p_flag |= P_EXEC; if ((p->p_flag2 & P2_NOTRACE_EXEC) == 0) p->p_flag2 &= ~P2_NOTRACE; if (p->p_flag & P_PPWAIT) { p->p_flag &= ~(P_PPWAIT | P_PPTRACE); cv_broadcast(&p->p_pwait); } /* * Implement image setuid/setgid. * * Don't honor setuid/setgid if the filesystem prohibits it or if * the process is being traced. * * We disable setuid/setgid/etc in compatibility mode on the basis * that most setugid applications are not written with that * environment in mind, and will therefore almost certainly operate * incorrectly. In principle there's no reason that setugid * applications might not be useful in capability mode, so we may want * to reconsider this conservative design choice in the future. * * XXXMAC: For the time being, use NOSUID to also prohibit * transitions on the file system. */ credential_changing = 0; credential_changing |= (attr.va_mode & S_ISUID) && oldcred->cr_uid != attr.va_uid; credential_changing |= (attr.va_mode & S_ISGID) && oldcred->cr_gid != attr.va_gid; #ifdef MAC will_transition = mac_vnode_execve_will_transition(oldcred, imgp->vp, interpvplabel, imgp); credential_changing |= will_transition; #endif if (credential_changing && #ifdef CAPABILITY_MODE ((oldcred->cr_flags & CRED_FLAG_CAPMODE) == 0) && #endif (imgp->vp->v_mount->mnt_flag & MNT_NOSUID) == 0 && (p->p_flag & P_TRACED) == 0) { /* * Turn off syscall tracing for set-id programs, except for * root. Record any set-id flags first to make sure that * we do not regain any tracing during a possible block. */ setsugid(p); #ifdef KTRACE if (p->p_tracecred != NULL && priv_check_cred(p->p_tracecred, PRIV_DEBUG_DIFFCRED, 0)) ktrprocexec(p, &tracecred, &tracevp); #endif /* * Close any file descriptors 0..2 that reference procfs, * then make sure file descriptors 0..2 are in use. * * Both fdsetugidsafety() and fdcheckstd() may call functions * taking sleepable locks, so temporarily drop our locks. */ PROC_UNLOCK(p); VOP_UNLOCK(imgp->vp, 0); fdsetugidsafety(td); error = fdcheckstd(td); if (error != 0) goto done1; newcred = crdup(oldcred); euip = uifind(attr.va_uid); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); PROC_LOCK(p); /* * Set the new credentials. */ if (attr.va_mode & S_ISUID) change_euid(newcred, euip); if (attr.va_mode & S_ISGID) change_egid(newcred, attr.va_gid); #ifdef MAC if (will_transition) { mac_vnode_execve_transition(oldcred, newcred, imgp->vp, interpvplabel, imgp); } #endif /* * Implement correct POSIX saved-id behavior. * * XXXMAC: Note that the current logic will save the * uid and gid if a MAC domain transition occurs, even * though maybe it shouldn't. */ change_svuid(newcred, newcred->cr_uid); change_svgid(newcred, newcred->cr_gid); proc_set_cred(p, newcred); } else { if (oldcred->cr_uid == oldcred->cr_ruid && oldcred->cr_gid == oldcred->cr_rgid) p->p_flag &= ~P_SUGID; /* * Implement correct POSIX saved-id behavior. * * XXX: It's not clear that the existing behavior is * POSIX-compliant. A number of sources indicate that the * saved uid/gid should only be updated if the new ruid is * not equal to the old ruid, or the new euid is not equal * to the old euid and the new euid is not equal to the old * ruid. The FreeBSD code always updates the saved uid/gid. * Also, this code uses the new (replaced) euid and egid as * the source, which may or may not be the right ones to use. */ if (oldcred->cr_svuid != oldcred->cr_uid || oldcred->cr_svgid != oldcred->cr_gid) { PROC_UNLOCK(p); VOP_UNLOCK(imgp->vp, 0); newcred = crdup(oldcred); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); PROC_LOCK(p); change_svuid(newcred, newcred->cr_uid); change_svgid(newcred, newcred->cr_gid); proc_set_cred(p, newcred); } } /* * Store the vp for use in procfs. This vnode was referenced prior * to locking the proc lock. */ textvp = p->p_textvp; p->p_textvp = binvp; #ifdef KDTRACE_HOOKS /* * Tell the DTrace fasttrap provider about the exec if it * has declared an interest. */ if (dtrace_fasttrap_exec) dtrace_fasttrap_exec(p); #endif /* * Notify others that we exec'd, and clear the P_INEXEC flag * as we're now a bona fide freshly-execed process. */ KNOTE_LOCKED(&p->p_klist, NOTE_EXEC); p->p_flag &= ~P_INEXEC; /* clear "fork but no exec" flag, as we _are_ execing */ p->p_acflag &= ~AFORK; /* * Free any previous argument cache and replace it with * the new argument cache, if any. */ oldargs = p->p_args; p->p_args = newargs; newargs = NULL; #ifdef HWPMC_HOOKS /* * Check if system-wide sampling is in effect or if the * current process is using PMCs. If so, do exec() time * processing. This processing needs to happen AFTER the * P_INEXEC flag is cleared. * * The proc lock needs to be released before taking the PMC * SX. */ if (PMC_SYSTEM_SAMPLING_ACTIVE() || PMC_PROC_IS_USING_PMCS(p)) { PROC_UNLOCK(p); VOP_UNLOCK(imgp->vp, 0); pe.pm_credentialschanged = credential_changing; pe.pm_entryaddr = imgp->entry_addr; PMC_CALL_HOOK_X(td, PMC_FN_PROCESS_EXEC, (void *) &pe); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); } else PROC_UNLOCK(p); #else /* !HWPMC_HOOKS */ PROC_UNLOCK(p); #endif /* Set values passed into the program in registers. */ if (p->p_sysent->sv_setregs) (*p->p_sysent->sv_setregs)(td, imgp, (u_long)(uintptr_t)stack_base); else exec_setregs(td, imgp, (u_long)(uintptr_t)stack_base); vfs_mark_atime(imgp->vp, td->td_ucred); SDT_PROBE(proc, kernel, , exec__success, args->fname, 0, 0, 0, 0); VOP_UNLOCK(imgp->vp, 0); done1: /* * Free any resources malloc'd earlier that we didn't use. */ if (euip != NULL) uifree(euip); if (newcred != NULL) crfree(oldcred); /* * Handle deferred decrement of ref counts. */ if (textvp != NULL) vrele(textvp); if (error != 0) vrele(binvp); #ifdef KTRACE if (tracevp != NULL) vrele(tracevp); if (tracecred != NULL) crfree(tracecred); #endif vn_lock(imgp->vp, LK_SHARED | LK_RETRY); pargs_drop(oldargs); pargs_drop(newargs); if (oldsigacts != NULL) sigacts_free(oldsigacts); exec_fail_dealloc: /* * free various allocated resources */ if (imgp->firstpage != NULL) exec_unmap_first_page(imgp); if (imgp->vp != NULL) { if (args->fname) NDFREE(&nd, NDF_ONLY_PNBUF); if (imgp->opened) VOP_CLOSE(imgp->vp, FREAD, td->td_ucred, td); vput(imgp->vp); } if (imgp->object != NULL) vm_object_deallocate(imgp->object); free(imgp->freepath, M_TEMP); if (error == 0) { PROC_LOCK(p); td->td_dbgflags |= TDB_EXEC; PROC_UNLOCK(p); /* * Stop the process here if its stop event mask has * the S_EXEC bit set. */ STOPEVENT(p, S_EXEC, 0); goto done2; } exec_fail: /* we're done here, clear P_INEXEC */ PROC_LOCK(p); p->p_flag &= ~P_INEXEC; PROC_UNLOCK(p); SDT_PROBE(proc, kernel, , exec__failure, error, 0, 0, 0, 0); done2: #ifdef MAC mac_execve_exit(imgp); mac_execve_interpreter_exit(interpvplabel); #endif exec_free_args(args); if (error && imgp->vmspace_destroyed) { /* sorry, no more process anymore. exit gracefully */ exit1(td, W_EXITCODE(0, SIGABRT)); /* NOT REACHED */ } #ifdef KTRACE if (error == 0) ktrprocctor(p); #endif return (error); } int exec_map_first_page(imgp) struct image_params *imgp; { int rv, i; int initial_pagein; vm_page_t ma[VM_INITIAL_PAGEIN]; vm_object_t object; if (imgp->firstpage != NULL) exec_unmap_first_page(imgp); object = imgp->vp->v_object; if (object == NULL) return (EACCES); VM_OBJECT_WLOCK(object); #if VM_NRESERVLEVEL > 0 - if ((object->flags & OBJ_COLORED) == 0) { - object->flags |= OBJ_COLORED; - object->pg_color = 0; - } + vm_object_color(object, 0); #endif ma[0] = vm_page_grab(object, 0, VM_ALLOC_NORMAL); if (ma[0]->valid != VM_PAGE_BITS_ALL) { initial_pagein = VM_INITIAL_PAGEIN; if (initial_pagein > object->size) initial_pagein = object->size; for (i = 1; i < initial_pagein; i++) { if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) { if (ma[i]->valid) break; if (vm_page_tryxbusy(ma[i])) break; } else { ma[i] = vm_page_alloc(object, i, VM_ALLOC_NORMAL | VM_ALLOC_IFNOTCACHED); if (ma[i] == NULL) break; } } initial_pagein = i; rv = vm_pager_get_pages(object, ma, initial_pagein, 0); ma[0] = vm_page_lookup(object, 0); if ((rv != VM_PAGER_OK) || (ma[0] == NULL)) { if (ma[0] != NULL) { vm_page_lock(ma[0]); vm_page_free(ma[0]); vm_page_unlock(ma[0]); } VM_OBJECT_WUNLOCK(object); return (EIO); } } vm_page_xunbusy(ma[0]); vm_page_lock(ma[0]); vm_page_hold(ma[0]); vm_page_activate(ma[0]); vm_page_unlock(ma[0]); VM_OBJECT_WUNLOCK(object); imgp->firstpage = sf_buf_alloc(ma[0], 0); imgp->image_header = (char *)sf_buf_kva(imgp->firstpage); return (0); } void exec_unmap_first_page(imgp) struct image_params *imgp; { vm_page_t m; if (imgp->firstpage != NULL) { m = sf_buf_page(imgp->firstpage); sf_buf_free(imgp->firstpage); imgp->firstpage = NULL; vm_page_lock(m); vm_page_unhold(m); vm_page_unlock(m); } } /* * Destroy old address space, and allocate a new stack * The new stack is only SGROWSIZ large because it is grown * automatically in trap.c. */ int exec_new_vmspace(imgp, sv) struct image_params *imgp; struct sysentvec *sv; { int error; struct proc *p = imgp->proc; struct vmspace *vmspace = p->p_vmspace; vm_object_t obj; vm_offset_t sv_minuser, stack_addr; vm_map_t map; u_long ssiz; imgp->vmspace_destroyed = 1; imgp->sysent = sv; /* May be called with Giant held */ EVENTHANDLER_INVOKE(process_exec, p, imgp); /* * Blow away entire process VM, if address space not shared, * otherwise, create a new VM space so that other threads are * not disrupted */ map = &vmspace->vm_map; if (map_at_zero) sv_minuser = sv->sv_minuser; else sv_minuser = MAX(sv->sv_minuser, PAGE_SIZE); if (vmspace->vm_refcnt == 1 && vm_map_min(map) == sv_minuser && vm_map_max(map) == sv->sv_maxuser) { shmexit(vmspace); pmap_remove_pages(vmspace_pmap(vmspace)); vm_map_remove(map, vm_map_min(map), vm_map_max(map)); } else { error = vmspace_exec(p, sv_minuser, sv->sv_maxuser); if (error) return (error); vmspace = p->p_vmspace; map = &vmspace->vm_map; } /* Map a shared page */ obj = sv->sv_shared_page_obj; if (obj != NULL) { vm_object_reference(obj); error = vm_map_fixed(map, obj, 0, sv->sv_shared_page_base, sv->sv_shared_page_len, VM_PROT_READ | VM_PROT_EXECUTE, VM_PROT_READ | VM_PROT_EXECUTE, MAP_INHERIT_SHARE | MAP_ACC_NO_CHARGE); if (error) { vm_object_deallocate(obj); return (error); } } /* Allocate a new stack */ if (sv->sv_maxssiz != NULL) ssiz = *sv->sv_maxssiz; else ssiz = maxssiz; stack_addr = sv->sv_usrstack - ssiz; error = vm_map_stack(map, stack_addr, (vm_size_t)ssiz, obj != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : sv->sv_stackprot, VM_PROT_ALL, MAP_STACK_GROWS_DOWN); if (error) return (error); /* * vm_ssize and vm_maxsaddr are somewhat antiquated concepts, but they * are still used to enforce the stack rlimit on the process stack. */ vmspace->vm_ssize = sgrowsiz >> PAGE_SHIFT; vmspace->vm_maxsaddr = (char *)sv->sv_usrstack - ssiz; return (0); } /* * Copy out argument and environment strings from the old process address * space into the temporary string buffer. */ int exec_copyin_args(struct image_args *args, char *fname, enum uio_seg segflg, char **argv, char **envv) { u_long argp, envp; int error; size_t length; bzero(args, sizeof(*args)); if (argv == NULL) return (EFAULT); /* * Allocate demand-paged memory for the file name, argument, and * environment strings. */ error = exec_alloc_args(args); if (error != 0) return (error); /* * Copy the file name. */ if (fname != NULL) { args->fname = args->buf; error = (segflg == UIO_SYSSPACE) ? copystr(fname, args->fname, PATH_MAX, &length) : copyinstr(fname, args->fname, PATH_MAX, &length); if (error != 0) goto err_exit; } else length = 0; args->begin_argv = args->buf + length; args->endp = args->begin_argv; args->stringspace = ARG_MAX; /* * extract arguments first */ for (;;) { error = fueword(argv++, &argp); if (error == -1) { error = EFAULT; goto err_exit; } if (argp == 0) break; error = copyinstr((void *)(uintptr_t)argp, args->endp, args->stringspace, &length); if (error != 0) { if (error == ENAMETOOLONG) error = E2BIG; goto err_exit; } args->stringspace -= length; args->endp += length; args->argc++; } args->begin_envv = args->endp; /* * extract environment strings */ if (envv) { for (;;) { error = fueword(envv++, &envp); if (error == -1) { error = EFAULT; goto err_exit; } if (envp == 0) break; error = copyinstr((void *)(uintptr_t)envp, args->endp, args->stringspace, &length); if (error != 0) { if (error == ENAMETOOLONG) error = E2BIG; goto err_exit; } args->stringspace -= length; args->endp += length; args->envc++; } } return (0); err_exit: exec_free_args(args); return (error); } /* * Allocate temporary demand-paged, zero-filled memory for the file name, * argument, and environment strings. Returns zero if the allocation succeeds * and ENOMEM otherwise. */ int exec_alloc_args(struct image_args *args) { args->buf = (char *)kmap_alloc_wait(exec_map, PATH_MAX + ARG_MAX); return (args->buf != NULL ? 0 : ENOMEM); } void exec_free_args(struct image_args *args) { if (args->buf != NULL) { kmap_free_wakeup(exec_map, (vm_offset_t)args->buf, PATH_MAX + ARG_MAX); args->buf = NULL; } if (args->fname_buf != NULL) { free(args->fname_buf, M_TEMP); args->fname_buf = NULL; } } /* * Copy strings out to the new process address space, constructing new arg * and env vector tables. Return a pointer to the base so that it can be used * as the initial stack pointer. */ register_t * exec_copyout_strings(imgp) struct image_params *imgp; { int argc, envc; char **vectp; char *stringp; uintptr_t destp; register_t *stack_base; struct ps_strings *arginfo; struct proc *p; size_t execpath_len; int szsigcode, szps; char canary[sizeof(long) * 8]; szps = sizeof(pagesizes[0]) * MAXPAGESIZES; /* * Calculate string base and vector table pointers. * Also deal with signal trampoline code for this exec type. */ if (imgp->execpath != NULL && imgp->auxargs != NULL) execpath_len = strlen(imgp->execpath) + 1; else execpath_len = 0; p = imgp->proc; szsigcode = 0; arginfo = (struct ps_strings *)p->p_sysent->sv_psstrings; if (p->p_sysent->sv_sigcode_base == 0) { if (p->p_sysent->sv_szsigcode != NULL) szsigcode = *(p->p_sysent->sv_szsigcode); } destp = (uintptr_t)arginfo; /* * install sigcode */ if (szsigcode != 0) { destp -= szsigcode; destp = rounddown2(destp, sizeof(void *)); copyout(p->p_sysent->sv_sigcode, (void *)destp, szsigcode); } /* * Copy the image path for the rtld. */ if (execpath_len != 0) { destp -= execpath_len; imgp->execpathp = destp; copyout(imgp->execpath, (void *)destp, execpath_len); } /* * Prepare the canary for SSP. */ arc4rand(canary, sizeof(canary), 0); destp -= sizeof(canary); imgp->canary = destp; copyout(canary, (void *)destp, sizeof(canary)); imgp->canarylen = sizeof(canary); /* * Prepare the pagesizes array. */ destp -= szps; destp = rounddown2(destp, sizeof(void *)); imgp->pagesizes = destp; copyout(pagesizes, (void *)destp, szps); imgp->pagesizeslen = szps; destp -= ARG_MAX - imgp->args->stringspace; destp = rounddown2(destp, sizeof(void *)); /* * If we have a valid auxargs ptr, prepare some room * on the stack. */ if (imgp->auxargs) { /* * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for * lower compatibility. */ imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size : (AT_COUNT * 2); /* * The '+ 2' is for the null pointers at the end of each of * the arg and env vector sets,and imgp->auxarg_size is room * for argument of Runtime loader. */ vectp = (char **)(destp - (imgp->args->argc + imgp->args->envc + 2 + imgp->auxarg_size) * sizeof(char *)); } else { /* * The '+ 2' is for the null pointers at the end of each of * the arg and env vector sets */ vectp = (char **)(destp - (imgp->args->argc + imgp->args->envc + 2) * sizeof(char *)); } /* * vectp also becomes our initial stack base */ stack_base = (register_t *)vectp; stringp = imgp->args->begin_argv; argc = imgp->args->argc; envc = imgp->args->envc; /* * Copy out strings - arguments and environment. */ copyout(stringp, (void *)destp, ARG_MAX - imgp->args->stringspace); /* * Fill in "ps_strings" struct for ps, w, etc. */ suword(&arginfo->ps_argvstr, (long)(intptr_t)vectp); suword32(&arginfo->ps_nargvstr, argc); /* * Fill in argument portion of vector table. */ for (; argc > 0; --argc) { suword(vectp++, (long)(intptr_t)destp); while (*stringp++ != 0) destp++; destp++; } /* a null vector table pointer separates the argp's from the envp's */ suword(vectp++, 0); suword(&arginfo->ps_envstr, (long)(intptr_t)vectp); suword32(&arginfo->ps_nenvstr, envc); /* * Fill in environment portion of vector table. */ for (; envc > 0; --envc) { suword(vectp++, (long)(intptr_t)destp); while (*stringp++ != 0) destp++; destp++; } /* end of vector table is a null pointer */ suword(vectp, 0); return (stack_base); } /* * Check permissions of file to execute. * Called with imgp->vp locked. * Return 0 for success or error code on failure. */ int exec_check_permissions(imgp) struct image_params *imgp; { struct vnode *vp = imgp->vp; struct vattr *attr = imgp->attr; struct thread *td; int error, writecount; td = curthread; /* Get file attributes */ error = VOP_GETATTR(vp, attr, td->td_ucred); if (error) return (error); #ifdef MAC error = mac_vnode_check_exec(td->td_ucred, imgp->vp, imgp); if (error) return (error); #endif /* * 1) Check if file execution is disabled for the filesystem that * this file resides on. * 2) Ensure that at least one execute bit is on. Otherwise, a * privileged user will always succeed, and we don't want this * to happen unless the file really is executable. * 3) Ensure that the file is a regular file. */ if ((vp->v_mount->mnt_flag & MNT_NOEXEC) || (attr->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0 || (attr->va_type != VREG)) return (EACCES); /* * Zero length files can't be exec'd */ if (attr->va_size == 0) return (ENOEXEC); /* * Check for execute permission to file based on current credentials. */ error = VOP_ACCESS(vp, VEXEC, td->td_ucred, td); if (error) return (error); /* * Check number of open-for-writes on the file and deny execution * if there are any. */ error = VOP_GET_WRITECOUNT(vp, &writecount); if (error != 0) return (error); if (writecount != 0) return (ETXTBSY); /* * Call filesystem specific open routine (which does nothing in the * general case). */ error = VOP_OPEN(vp, FREAD, td->td_ucred, td, NULL); if (error == 0) imgp->opened = 1; return (error); } /* * Exec handler registration */ int exec_register(execsw_arg) const struct execsw *execsw_arg; { const struct execsw **es, **xs, **newexecsw; int count = 2; /* New slot and trailing NULL */ if (execsw) for (es = execsw; *es; es++) count++; newexecsw = malloc(count * sizeof(*es), M_TEMP, M_WAITOK); if (newexecsw == NULL) return (ENOMEM); xs = newexecsw; if (execsw) for (es = execsw; *es; es++) *xs++ = *es; *xs++ = execsw_arg; *xs = NULL; if (execsw) free(execsw, M_TEMP); execsw = newexecsw; return (0); } int exec_unregister(execsw_arg) const struct execsw *execsw_arg; { const struct execsw **es, **xs, **newexecsw; int count = 1; if (execsw == NULL) panic("unregister with no handlers left?\n"); for (es = execsw; *es; es++) { if (*es == execsw_arg) break; } if (*es == NULL) return (ENOENT); for (es = execsw; *es; es++) if (*es != execsw_arg) count++; newexecsw = malloc(count * sizeof(*es), M_TEMP, M_WAITOK); if (newexecsw == NULL) return (ENOMEM); xs = newexecsw; for (es = execsw; *es; es++) if (*es != execsw_arg) *xs++ = *es; *xs = NULL; if (execsw) free(execsw, M_TEMP); execsw = newexecsw; return (0); } Index: head/sys/vm/vm_fault.c =================================================================== --- head/sys/vm/vm_fault.c (revision 280326) +++ head/sys/vm/vm_fault.c (revision 280327) @@ -1,1596 +1,1593 @@ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * Copyright (c) 1994 John S. Dyson * All rights reserved. * Copyright (c) 1994 David Greenman * 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. * 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: @(#)vm_fault.c 8.4 (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. */ /* * Page fault handling module. */ #include __FBSDID("$FreeBSD$"); #include "opt_ktrace.h" #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #ifdef KTRACE #include #endif #include #include #include #include #include #include #include #include #include #include #include #define PFBAK 4 #define PFFOR 4 static int vm_fault_additional_pages(vm_page_t, int, int, vm_page_t *, int *); #define VM_FAULT_READ_BEHIND 8 #define VM_FAULT_READ_DEFAULT (1 + VM_FAULT_READ_AHEAD_INIT) #define VM_FAULT_READ_MAX (1 + VM_FAULT_READ_AHEAD_MAX) #define VM_FAULT_NINCR (VM_FAULT_READ_MAX / VM_FAULT_READ_BEHIND) #define VM_FAULT_SUM (VM_FAULT_NINCR * (VM_FAULT_NINCR + 1) / 2) #define VM_FAULT_CACHE_BEHIND (VM_FAULT_READ_BEHIND * VM_FAULT_SUM) struct faultstate { vm_page_t m; vm_object_t object; vm_pindex_t pindex; vm_page_t first_m; vm_object_t first_object; vm_pindex_t first_pindex; vm_map_t map; vm_map_entry_t entry; int lookup_still_valid; struct vnode *vp; }; static void vm_fault_cache_behind(const struct faultstate *fs, int distance); static void vm_fault_prefault(const struct faultstate *fs, vm_offset_t addra, int faultcount, int reqpage); static inline void release_page(struct faultstate *fs) { vm_page_xunbusy(fs->m); vm_page_lock(fs->m); vm_page_deactivate(fs->m); vm_page_unlock(fs->m); fs->m = NULL; } static inline void unlock_map(struct faultstate *fs) { if (fs->lookup_still_valid) { vm_map_lookup_done(fs->map, fs->entry); fs->lookup_still_valid = FALSE; } } static void unlock_and_deallocate(struct faultstate *fs) { vm_object_pip_wakeup(fs->object); VM_OBJECT_WUNLOCK(fs->object); if (fs->object != fs->first_object) { VM_OBJECT_WLOCK(fs->first_object); vm_page_lock(fs->first_m); vm_page_free(fs->first_m); vm_page_unlock(fs->first_m); vm_object_pip_wakeup(fs->first_object); VM_OBJECT_WUNLOCK(fs->first_object); fs->first_m = NULL; } vm_object_deallocate(fs->first_object); unlock_map(fs); if (fs->vp != NULL) { vput(fs->vp); fs->vp = NULL; } } static void vm_fault_dirty(vm_map_entry_t entry, vm_page_t m, vm_prot_t prot, vm_prot_t fault_type, int fault_flags, boolean_t set_wd) { boolean_t need_dirty; if (((prot & VM_PROT_WRITE) == 0 && (fault_flags & VM_FAULT_DIRTY) == 0) || (m->oflags & VPO_UNMANAGED) != 0) return; VM_OBJECT_ASSERT_LOCKED(m->object); need_dirty = ((fault_type & VM_PROT_WRITE) != 0 && (fault_flags & VM_FAULT_CHANGE_WIRING) == 0) || (fault_flags & VM_FAULT_DIRTY) != 0; if (set_wd) vm_object_set_writeable_dirty(m->object); else /* * If two callers of vm_fault_dirty() with set_wd == * FALSE, one for the map entry with MAP_ENTRY_NOSYNC * flag set, other with flag clear, race, it is * possible for the no-NOSYNC thread to see m->dirty * != 0 and not clear VPO_NOSYNC. Take vm_page lock * around manipulation of VPO_NOSYNC and * vm_page_dirty() call, to avoid the race and keep * m->oflags consistent. */ vm_page_lock(m); /* * If this is a NOSYNC mmap we do not want to set VPO_NOSYNC * if the page is already dirty to prevent data written with * the expectation of being synced from not being synced. * Likewise if this entry does not request NOSYNC then make * sure the page isn't marked NOSYNC. Applications sharing * data should use the same flags to avoid ping ponging. */ if ((entry->eflags & MAP_ENTRY_NOSYNC) != 0) { if (m->dirty == 0) { m->oflags |= VPO_NOSYNC; } } else { m->oflags &= ~VPO_NOSYNC; } /* * If the fault is a write, we know that this page is being * written NOW so dirty it explicitly to save on * pmap_is_modified() calls later. * * Also tell the backing pager, if any, that it should remove * any swap backing since the page is now dirty. */ if (need_dirty) vm_page_dirty(m); if (!set_wd) vm_page_unlock(m); if (need_dirty) vm_pager_page_unswapped(m); } /* * TRYPAGER - used by vm_fault to calculate whether the pager for the * current object *might* contain the page. * * default objects are zero-fill, there is no real pager. */ #define TRYPAGER (fs.object->type != OBJT_DEFAULT && \ ((fault_flags & VM_FAULT_CHANGE_WIRING) == 0 || wired)) /* * vm_fault: * * Handle a page fault occurring at the given address, * requiring the given permissions, in the map specified. * If successful, the page is inserted into the * associated physical map. * * NOTE: the given address should be truncated to the * proper page address. * * KERN_SUCCESS is returned if the page fault is handled; otherwise, * a standard error specifying why the fault is fatal is returned. * * The map in question must be referenced, and remains so. * Caller may hold no locks. */ int vm_fault(vm_map_t map, vm_offset_t vaddr, vm_prot_t fault_type, int fault_flags) { struct thread *td; int result; td = curthread; if ((td->td_pflags & TDP_NOFAULTING) != 0) return (KERN_PROTECTION_FAILURE); #ifdef KTRACE if (map != kernel_map && KTRPOINT(td, KTR_FAULT)) ktrfault(vaddr, fault_type); #endif result = vm_fault_hold(map, trunc_page(vaddr), fault_type, fault_flags, NULL); #ifdef KTRACE if (map != kernel_map && KTRPOINT(td, KTR_FAULTEND)) ktrfaultend(result); #endif return (result); } int vm_fault_hold(vm_map_t map, vm_offset_t vaddr, vm_prot_t fault_type, int fault_flags, vm_page_t *m_hold) { vm_prot_t prot; int alloc_req, era, faultcount, nera, reqpage, result; boolean_t growstack, is_first_object_locked, wired; int map_generation; vm_object_t next_object; vm_page_t marray[VM_FAULT_READ_MAX]; int hardfault; struct faultstate fs; struct vnode *vp; vm_page_t m; int ahead, behind, cluster_offset, error, locked; hardfault = 0; growstack = TRUE; PCPU_INC(cnt.v_vm_faults); fs.vp = NULL; faultcount = reqpage = 0; RetryFault:; /* * Find the backing store object and offset into it to begin the * search. */ fs.map = map; result = vm_map_lookup(&fs.map, vaddr, fault_type, &fs.entry, &fs.first_object, &fs.first_pindex, &prot, &wired); if (result != KERN_SUCCESS) { if (growstack && result == KERN_INVALID_ADDRESS && map != kernel_map) { result = vm_map_growstack(curproc, vaddr); if (result != KERN_SUCCESS) return (KERN_FAILURE); growstack = FALSE; goto RetryFault; } return (result); } map_generation = fs.map->timestamp; if (fs.entry->eflags & MAP_ENTRY_NOFAULT) { panic("vm_fault: fault on nofault entry, addr: %lx", (u_long)vaddr); } if (fs.entry->eflags & MAP_ENTRY_IN_TRANSITION && fs.entry->wiring_thread != curthread) { vm_map_unlock_read(fs.map); vm_map_lock(fs.map); if (vm_map_lookup_entry(fs.map, vaddr, &fs.entry) && (fs.entry->eflags & MAP_ENTRY_IN_TRANSITION)) { fs.entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; vm_map_unlock_and_wait(fs.map, 0); } else vm_map_unlock(fs.map); goto RetryFault; } if (wired) fault_type = prot | (fault_type & VM_PROT_COPY); if (fs.vp == NULL /* avoid locked vnode leak */ && (fault_flags & (VM_FAULT_CHANGE_WIRING | VM_FAULT_DIRTY)) == 0 && /* avoid calling vm_object_set_writeable_dirty() */ ((prot & VM_PROT_WRITE) == 0 || (fs.first_object->type != OBJT_VNODE && (fs.first_object->flags & OBJ_TMPFS_NODE) == 0) || (fs.first_object->flags & OBJ_MIGHTBEDIRTY) != 0)) { VM_OBJECT_RLOCK(fs.first_object); if ((prot & VM_PROT_WRITE) != 0 && (fs.first_object->type == OBJT_VNODE || (fs.first_object->flags & OBJ_TMPFS_NODE) != 0) && (fs.first_object->flags & OBJ_MIGHTBEDIRTY) == 0) goto fast_failed; m = vm_page_lookup(fs.first_object, fs.first_pindex); /* A busy page can be mapped for read|execute access. */ if (m == NULL || ((prot & VM_PROT_WRITE) != 0 && vm_page_busied(m)) || m->valid != VM_PAGE_BITS_ALL) goto fast_failed; result = pmap_enter(fs.map->pmap, vaddr, m, prot, fault_type | PMAP_ENTER_NOSLEEP | (wired ? PMAP_ENTER_WIRED : 0), 0); if (result != KERN_SUCCESS) goto fast_failed; if (m_hold != NULL) { *m_hold = m; vm_page_lock(m); vm_page_hold(m); vm_page_unlock(m); } vm_fault_dirty(fs.entry, m, prot, fault_type, fault_flags, FALSE); VM_OBJECT_RUNLOCK(fs.first_object); if (!wired) vm_fault_prefault(&fs, vaddr, 0, 0); vm_map_lookup_done(fs.map, fs.entry); curthread->td_ru.ru_minflt++; return (KERN_SUCCESS); fast_failed: if (!VM_OBJECT_TRYUPGRADE(fs.first_object)) { VM_OBJECT_RUNLOCK(fs.first_object); VM_OBJECT_WLOCK(fs.first_object); } } else { VM_OBJECT_WLOCK(fs.first_object); } /* * Make a reference to this object to prevent its disposal while we * are messing with it. Once we have the reference, the map is free * to be diddled. Since objects reference their shadows (and copies), * they will stay around as well. * * Bump the paging-in-progress count to prevent size changes (e.g. * truncation operations) during I/O. This must be done after * obtaining the vnode lock in order to avoid possible deadlocks. */ vm_object_reference_locked(fs.first_object); vm_object_pip_add(fs.first_object, 1); fs.lookup_still_valid = TRUE; fs.first_m = NULL; /* * Search for the page at object/offset. */ fs.object = fs.first_object; fs.pindex = fs.first_pindex; while (TRUE) { /* * If the object is dead, we stop here */ if (fs.object->flags & OBJ_DEAD) { unlock_and_deallocate(&fs); return (KERN_PROTECTION_FAILURE); } /* * See if page is resident */ fs.m = vm_page_lookup(fs.object, fs.pindex); if (fs.m != NULL) { /* * Wait/Retry if the page is busy. We have to do this * if the page is either exclusive or shared busy * because the vm_pager may be using read busy for * pageouts (and even pageins if it is the vnode * pager), and we could end up trying to pagein and * pageout the same page simultaneously. * * We can theoretically allow the busy case on a read * fault if the page is marked valid, but since such * pages are typically already pmap'd, putting that * special case in might be more effort then it is * worth. We cannot under any circumstances mess * around with a shared busied page except, perhaps, * to pmap it. */ if (vm_page_busied(fs.m)) { /* * Reference the page before unlocking and * sleeping so that the page daemon is less * likely to reclaim it. */ vm_page_aflag_set(fs.m, PGA_REFERENCED); if (fs.object != fs.first_object) { if (!VM_OBJECT_TRYWLOCK( fs.first_object)) { VM_OBJECT_WUNLOCK(fs.object); VM_OBJECT_WLOCK(fs.first_object); VM_OBJECT_WLOCK(fs.object); } vm_page_lock(fs.first_m); vm_page_free(fs.first_m); vm_page_unlock(fs.first_m); vm_object_pip_wakeup(fs.first_object); VM_OBJECT_WUNLOCK(fs.first_object); fs.first_m = NULL; } unlock_map(&fs); if (fs.m == vm_page_lookup(fs.object, fs.pindex)) { vm_page_sleep_if_busy(fs.m, "vmpfw"); } vm_object_pip_wakeup(fs.object); VM_OBJECT_WUNLOCK(fs.object); PCPU_INC(cnt.v_intrans); vm_object_deallocate(fs.first_object); goto RetryFault; } vm_page_lock(fs.m); vm_page_remque(fs.m); vm_page_unlock(fs.m); /* * Mark page busy for other processes, and the * pagedaemon. If it still isn't completely valid * (readable), jump to readrest, else break-out ( we * found the page ). */ vm_page_xbusy(fs.m); if (fs.m->valid != VM_PAGE_BITS_ALL) goto readrest; break; } /* * Page is not resident, If this is the search termination * or the pager might contain the page, allocate a new page. */ if (TRYPAGER || fs.object == fs.first_object) { if (fs.pindex >= fs.object->size) { unlock_and_deallocate(&fs); return (KERN_PROTECTION_FAILURE); } /* * Allocate a new page for this object/offset pair. * * Unlocked read of the p_flag is harmless. At * worst, the P_KILLED might be not observed * there, and allocation can fail, causing * restart and new reading of the p_flag. */ fs.m = NULL; if (!vm_page_count_severe() || P_KILLED(curproc)) { #if VM_NRESERVLEVEL > 0 - if ((fs.object->flags & OBJ_COLORED) == 0) { - fs.object->flags |= OBJ_COLORED; - fs.object->pg_color = atop(vaddr) - - fs.pindex; - } + vm_object_color(fs.object, atop(vaddr) - + fs.pindex); #endif alloc_req = P_KILLED(curproc) ? VM_ALLOC_SYSTEM : VM_ALLOC_NORMAL; if (fs.object->type != OBJT_VNODE && fs.object->backing_object == NULL) alloc_req |= VM_ALLOC_ZERO; fs.m = vm_page_alloc(fs.object, fs.pindex, alloc_req); } if (fs.m == NULL) { unlock_and_deallocate(&fs); VM_WAITPFAULT; goto RetryFault; } else if (fs.m->valid == VM_PAGE_BITS_ALL) break; } readrest: /* * We have found a valid page or we have allocated a new page. * The page thus may not be valid or may not be entirely * valid. * * Attempt to fault-in the page if there is a chance that the * pager has it, and potentially fault in additional pages * at the same time. */ if (TRYPAGER) { int rv; u_char behavior = vm_map_entry_behavior(fs.entry); era = fs.entry->read_ahead; if (behavior == MAP_ENTRY_BEHAV_RANDOM || P_KILLED(curproc)) { behind = 0; nera = 0; ahead = 0; } else if (behavior == MAP_ENTRY_BEHAV_SEQUENTIAL) { behind = 0; nera = VM_FAULT_READ_AHEAD_MAX; ahead = nera; if (fs.pindex == fs.entry->next_read) vm_fault_cache_behind(&fs, VM_FAULT_READ_MAX); } else if (fs.pindex == fs.entry->next_read) { /* * This is a sequential fault. Arithmetically * increase the requested number of pages in * the read-ahead window. The requested * number of pages is "# of sequential faults * x (read ahead min + 1) + read ahead min" */ behind = 0; nera = VM_FAULT_READ_AHEAD_MIN; if (era > 0) { nera += era + 1; if (nera > VM_FAULT_READ_AHEAD_MAX) nera = VM_FAULT_READ_AHEAD_MAX; } ahead = nera; if (era == VM_FAULT_READ_AHEAD_MAX) vm_fault_cache_behind(&fs, VM_FAULT_CACHE_BEHIND); } else { /* * This is a non-sequential fault. Request a * cluster of pages that is aligned to a * VM_FAULT_READ_DEFAULT page offset boundary * within the object. Alignment to a page * offset boundary is more likely to coincide * with the underlying file system block than * alignment to a virtual address boundary. */ cluster_offset = fs.pindex % VM_FAULT_READ_DEFAULT; behind = ulmin(cluster_offset, atop(vaddr - fs.entry->start)); nera = 0; ahead = VM_FAULT_READ_DEFAULT - 1 - cluster_offset; } ahead = ulmin(ahead, atop(fs.entry->end - vaddr) - 1); if (era != nera) fs.entry->read_ahead = nera; /* * Call the pager to retrieve the data, if any, after * releasing the lock on the map. We hold a ref on * fs.object and the pages are exclusive busied. */ unlock_map(&fs); if (fs.object->type == OBJT_VNODE) { vp = fs.object->handle; if (vp == fs.vp) goto vnode_locked; else if (fs.vp != NULL) { vput(fs.vp); fs.vp = NULL; } locked = VOP_ISLOCKED(vp); if (locked != LK_EXCLUSIVE) locked = LK_SHARED; /* Do not sleep for vnode lock while fs.m is busy */ error = vget(vp, locked | LK_CANRECURSE | LK_NOWAIT, curthread); if (error != 0) { vhold(vp); release_page(&fs); unlock_and_deallocate(&fs); error = vget(vp, locked | LK_RETRY | LK_CANRECURSE, curthread); vdrop(vp); fs.vp = vp; KASSERT(error == 0, ("vm_fault: vget failed")); goto RetryFault; } fs.vp = vp; } vnode_locked: KASSERT(fs.vp == NULL || !fs.map->system_map, ("vm_fault: vnode-backed object mapped by system map")); /* * now we find out if any other pages should be paged * in at this time this routine checks to see if the * pages surrounding this fault reside in the same * object as the page for this fault. If they do, * then they are faulted in also into the object. The * array "marray" returned contains an array of * vm_page_t structs where one of them is the * vm_page_t passed to the routine. The reqpage * return value is the index into the marray for the * vm_page_t passed to the routine. * * fs.m plus the additional pages are exclusive busied. */ faultcount = vm_fault_additional_pages( fs.m, behind, ahead, marray, &reqpage); rv = faultcount ? vm_pager_get_pages(fs.object, marray, faultcount, reqpage) : VM_PAGER_FAIL; if (rv == VM_PAGER_OK) { /* * Found the page. Leave it busy while we play * with it. */ /* * Relookup in case pager changed page. Pager * is responsible for disposition of old page * if moved. */ fs.m = vm_page_lookup(fs.object, fs.pindex); if (!fs.m) { unlock_and_deallocate(&fs); goto RetryFault; } hardfault++; break; /* break to PAGE HAS BEEN FOUND */ } /* * Remove the bogus page (which does not exist at this * object/offset); before doing so, we must get back * our object lock to preserve our invariant. * * Also wake up any other process that may want to bring * in this page. * * If this is the top-level object, we must leave the * busy page to prevent another process from rushing * past us, and inserting the page in that object at * the same time that we are. */ if (rv == VM_PAGER_ERROR) printf("vm_fault: pager read error, pid %d (%s)\n", curproc->p_pid, curproc->p_comm); /* * Data outside the range of the pager or an I/O error */ /* * XXX - the check for kernel_map is a kludge to work * around having the machine panic on a kernel space * fault w/ I/O error. */ if (((fs.map != kernel_map) && (rv == VM_PAGER_ERROR)) || (rv == VM_PAGER_BAD)) { vm_page_lock(fs.m); vm_page_free(fs.m); vm_page_unlock(fs.m); fs.m = NULL; unlock_and_deallocate(&fs); return ((rv == VM_PAGER_ERROR) ? KERN_FAILURE : KERN_PROTECTION_FAILURE); } if (fs.object != fs.first_object) { vm_page_lock(fs.m); vm_page_free(fs.m); vm_page_unlock(fs.m); fs.m = NULL; /* * XXX - we cannot just fall out at this * point, m has been freed and is invalid! */ } } /* * We get here if the object has default pager (or unwiring) * or the pager doesn't have the page. */ if (fs.object == fs.first_object) fs.first_m = fs.m; /* * Move on to the next object. Lock the next object before * unlocking the current one. */ fs.pindex += OFF_TO_IDX(fs.object->backing_object_offset); next_object = fs.object->backing_object; if (next_object == NULL) { /* * If there's no object left, fill the page in the top * object with zeros. */ if (fs.object != fs.first_object) { vm_object_pip_wakeup(fs.object); VM_OBJECT_WUNLOCK(fs.object); fs.object = fs.first_object; fs.pindex = fs.first_pindex; fs.m = fs.first_m; VM_OBJECT_WLOCK(fs.object); } fs.first_m = NULL; /* * Zero the page if necessary and mark it valid. */ if ((fs.m->flags & PG_ZERO) == 0) { pmap_zero_page(fs.m); } else { PCPU_INC(cnt.v_ozfod); } PCPU_INC(cnt.v_zfod); fs.m->valid = VM_PAGE_BITS_ALL; /* Don't try to prefault neighboring pages. */ faultcount = 1; break; /* break to PAGE HAS BEEN FOUND */ } else { KASSERT(fs.object != next_object, ("object loop %p", next_object)); VM_OBJECT_WLOCK(next_object); vm_object_pip_add(next_object, 1); if (fs.object != fs.first_object) vm_object_pip_wakeup(fs.object); VM_OBJECT_WUNLOCK(fs.object); fs.object = next_object; } } vm_page_assert_xbusied(fs.m); /* * PAGE HAS BEEN FOUND. [Loop invariant still holds -- the object lock * is held.] */ /* * If the page is being written, but isn't already owned by the * top-level object, we have to copy it into a new page owned by the * top-level object. */ if (fs.object != fs.first_object) { /* * We only really need to copy if we want to write it. */ if ((fault_type & (VM_PROT_COPY | VM_PROT_WRITE)) != 0) { /* * This allows pages to be virtually copied from a * backing_object into the first_object, where the * backing object has no other refs to it, and cannot * gain any more refs. Instead of a bcopy, we just * move the page from the backing object to the * first object. Note that we must mark the page * dirty in the first object so that it will go out * to swap when needed. */ is_first_object_locked = FALSE; if ( /* * Only one shadow object */ (fs.object->shadow_count == 1) && /* * No COW refs, except us */ (fs.object->ref_count == 1) && /* * No one else can look this object up */ (fs.object->handle == NULL) && /* * No other ways to look the object up */ ((fs.object->type == OBJT_DEFAULT) || (fs.object->type == OBJT_SWAP)) && (is_first_object_locked = VM_OBJECT_TRYWLOCK(fs.first_object)) && /* * We don't chase down the shadow chain */ fs.object == fs.first_object->backing_object) { /* * get rid of the unnecessary page */ vm_page_lock(fs.first_m); vm_page_free(fs.first_m); vm_page_unlock(fs.first_m); /* * grab the page and put it into the * process'es object. The page is * automatically made dirty. */ if (vm_page_rename(fs.m, fs.first_object, fs.first_pindex)) { unlock_and_deallocate(&fs); goto RetryFault; } #if VM_NRESERVLEVEL > 0 /* * Rename the reservation. */ vm_reserv_rename(fs.m, fs.first_object, fs.object, OFF_TO_IDX( fs.first_object->backing_object_offset)); #endif vm_page_xbusy(fs.m); fs.first_m = fs.m; fs.m = NULL; PCPU_INC(cnt.v_cow_optim); } else { /* * Oh, well, lets copy it. */ pmap_copy_page(fs.m, fs.first_m); fs.first_m->valid = VM_PAGE_BITS_ALL; if (wired && (fault_flags & VM_FAULT_CHANGE_WIRING) == 0) { vm_page_lock(fs.first_m); vm_page_wire(fs.first_m); vm_page_unlock(fs.first_m); vm_page_lock(fs.m); vm_page_unwire(fs.m, PQ_INACTIVE); vm_page_unlock(fs.m); } /* * We no longer need the old page or object. */ release_page(&fs); } /* * fs.object != fs.first_object due to above * conditional */ vm_object_pip_wakeup(fs.object); VM_OBJECT_WUNLOCK(fs.object); /* * Only use the new page below... */ fs.object = fs.first_object; fs.pindex = fs.first_pindex; fs.m = fs.first_m; if (!is_first_object_locked) VM_OBJECT_WLOCK(fs.object); PCPU_INC(cnt.v_cow_faults); curthread->td_cow++; } else { prot &= ~VM_PROT_WRITE; } } /* * We must verify that the maps have not changed since our last * lookup. */ if (!fs.lookup_still_valid) { vm_object_t retry_object; vm_pindex_t retry_pindex; vm_prot_t retry_prot; if (!vm_map_trylock_read(fs.map)) { release_page(&fs); unlock_and_deallocate(&fs); goto RetryFault; } fs.lookup_still_valid = TRUE; if (fs.map->timestamp != map_generation) { result = vm_map_lookup_locked(&fs.map, vaddr, fault_type, &fs.entry, &retry_object, &retry_pindex, &retry_prot, &wired); /* * If we don't need the page any longer, put it on the inactive * list (the easiest thing to do here). If no one needs it, * pageout will grab it eventually. */ if (result != KERN_SUCCESS) { release_page(&fs); unlock_and_deallocate(&fs); /* * If retry of map lookup would have blocked then * retry fault from start. */ if (result == KERN_FAILURE) goto RetryFault; return (result); } if ((retry_object != fs.first_object) || (retry_pindex != fs.first_pindex)) { release_page(&fs); unlock_and_deallocate(&fs); goto RetryFault; } /* * Check whether the protection has changed or the object has * been copied while we left the map unlocked. Changing from * read to write permission is OK - we leave the page * write-protected, and catch the write fault. Changing from * write to read permission means that we can't mark the page * write-enabled after all. */ prot &= retry_prot; } } /* * If the page was filled by a pager, update the map entry's * last read offset. Since the pager does not return the * actual set of pages that it read, this update is based on * the requested set. Typically, the requested and actual * sets are the same. * * XXX The following assignment modifies the map * without holding a write lock on it. */ if (hardfault) fs.entry->next_read = fs.pindex + faultcount - reqpage; vm_fault_dirty(fs.entry, fs.m, prot, fault_type, fault_flags, TRUE); vm_page_assert_xbusied(fs.m); /* * Page must be completely valid or it is not fit to * map into user space. vm_pager_get_pages() ensures this. */ KASSERT(fs.m->valid == VM_PAGE_BITS_ALL, ("vm_fault: page %p partially invalid", fs.m)); VM_OBJECT_WUNLOCK(fs.object); /* * Put this page into the physical map. We had to do the unlock above * because pmap_enter() may sleep. We don't put the page * back on the active queue until later so that the pageout daemon * won't find it (yet). */ pmap_enter(fs.map->pmap, vaddr, fs.m, prot, fault_type | (wired ? PMAP_ENTER_WIRED : 0), 0); if (faultcount != 1 && (fault_flags & VM_FAULT_CHANGE_WIRING) == 0 && wired == 0) vm_fault_prefault(&fs, vaddr, faultcount, reqpage); VM_OBJECT_WLOCK(fs.object); vm_page_lock(fs.m); /* * If the page is not wired down, then put it where the pageout daemon * can find it. */ if (fault_flags & VM_FAULT_CHANGE_WIRING) { if (wired) vm_page_wire(fs.m); else vm_page_unwire(fs.m, PQ_ACTIVE); } else vm_page_activate(fs.m); if (m_hold != NULL) { *m_hold = fs.m; vm_page_hold(fs.m); } vm_page_unlock(fs.m); vm_page_xunbusy(fs.m); /* * Unlock everything, and return */ unlock_and_deallocate(&fs); if (hardfault) { PCPU_INC(cnt.v_io_faults); curthread->td_ru.ru_majflt++; } else curthread->td_ru.ru_minflt++; return (KERN_SUCCESS); } /* * Speed up the reclamation of up to "distance" pages that precede the * faulting pindex within the first object of the shadow chain. */ static void vm_fault_cache_behind(const struct faultstate *fs, int distance) { vm_object_t first_object, object; vm_page_t m, m_prev; vm_pindex_t pindex; object = fs->object; VM_OBJECT_ASSERT_WLOCKED(object); first_object = fs->first_object; if (first_object != object) { if (!VM_OBJECT_TRYWLOCK(first_object)) { VM_OBJECT_WUNLOCK(object); VM_OBJECT_WLOCK(first_object); VM_OBJECT_WLOCK(object); } } /* Neither fictitious nor unmanaged pages can be cached. */ if ((first_object->flags & (OBJ_FICTITIOUS | OBJ_UNMANAGED)) == 0) { if (fs->first_pindex < distance) pindex = 0; else pindex = fs->first_pindex - distance; if (pindex < OFF_TO_IDX(fs->entry->offset)) pindex = OFF_TO_IDX(fs->entry->offset); m = first_object != object ? fs->first_m : fs->m; vm_page_assert_xbusied(m); m_prev = vm_page_prev(m); while ((m = m_prev) != NULL && m->pindex >= pindex && m->valid == VM_PAGE_BITS_ALL) { m_prev = vm_page_prev(m); if (vm_page_busied(m)) continue; vm_page_lock(m); if (m->hold_count == 0 && m->wire_count == 0) { pmap_remove_all(m); vm_page_aflag_clear(m, PGA_REFERENCED); if (m->dirty != 0) vm_page_deactivate(m); else vm_page_cache(m); } vm_page_unlock(m); } } if (first_object != object) VM_OBJECT_WUNLOCK(first_object); } /* * vm_fault_prefault provides a quick way of clustering * pagefaults into a processes address space. It is a "cousin" * of vm_map_pmap_enter, except it runs at page fault time instead * of mmap time. */ static void vm_fault_prefault(const struct faultstate *fs, vm_offset_t addra, int faultcount, int reqpage) { pmap_t pmap; vm_map_entry_t entry; vm_object_t backing_object, lobject; vm_offset_t addr, starta; vm_pindex_t pindex; vm_page_t m; int backward, forward, i; pmap = fs->map->pmap; if (pmap != vmspace_pmap(curthread->td_proc->p_vmspace)) return; if (faultcount > 0) { backward = reqpage; forward = faultcount - reqpage - 1; } else { backward = PFBAK; forward = PFFOR; } entry = fs->entry; starta = addra - backward * PAGE_SIZE; if (starta < entry->start) { starta = entry->start; } else if (starta > addra) { starta = 0; } /* * Generate the sequence of virtual addresses that are candidates for * prefaulting in an outward spiral from the faulting virtual address, * "addra". Specifically, the sequence is "addra - PAGE_SIZE", "addra * + PAGE_SIZE", "addra - 2 * PAGE_SIZE", "addra + 2 * PAGE_SIZE", ... * If the candidate address doesn't have a backing physical page, then * the loop immediately terminates. */ for (i = 0; i < 2 * imax(backward, forward); i++) { addr = addra + ((i >> 1) + 1) * ((i & 1) == 0 ? -PAGE_SIZE : PAGE_SIZE); if (addr > addra + forward * PAGE_SIZE) addr = 0; if (addr < starta || addr >= entry->end) continue; if (!pmap_is_prefaultable(pmap, addr)) continue; pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; lobject = entry->object.vm_object; VM_OBJECT_RLOCK(lobject); while ((m = vm_page_lookup(lobject, pindex)) == NULL && lobject->type == OBJT_DEFAULT && (backing_object = lobject->backing_object) != NULL) { KASSERT((lobject->backing_object_offset & PAGE_MASK) == 0, ("vm_fault_prefault: unaligned object offset")); pindex += lobject->backing_object_offset >> PAGE_SHIFT; VM_OBJECT_RLOCK(backing_object); VM_OBJECT_RUNLOCK(lobject); lobject = backing_object; } if (m == NULL) { VM_OBJECT_RUNLOCK(lobject); break; } if (m->valid == VM_PAGE_BITS_ALL && (m->flags & PG_FICTITIOUS) == 0) pmap_enter_quick(pmap, addr, m, entry->protection); VM_OBJECT_RUNLOCK(lobject); } } /* * Hold each of the physical pages that are mapped by the specified range of * virtual addresses, ["addr", "addr" + "len"), if those mappings are valid * and allow the specified types of access, "prot". If all of the implied * pages are successfully held, then the number of held pages is returned * together with pointers to those pages in the array "ma". However, if any * of the pages cannot be held, -1 is returned. */ int vm_fault_quick_hold_pages(vm_map_t map, vm_offset_t addr, vm_size_t len, vm_prot_t prot, vm_page_t *ma, int max_count) { vm_offset_t end, va; vm_page_t *mp; int count; boolean_t pmap_failed; if (len == 0) return (0); end = round_page(addr + len); addr = trunc_page(addr); /* * Check for illegal addresses. */ if (addr < vm_map_min(map) || addr > end || end > vm_map_max(map)) return (-1); if (atop(end - addr) > max_count) panic("vm_fault_quick_hold_pages: count > max_count"); count = atop(end - addr); /* * Most likely, the physical pages are resident in the pmap, so it is * faster to try pmap_extract_and_hold() first. */ pmap_failed = FALSE; for (mp = ma, va = addr; va < end; mp++, va += PAGE_SIZE) { *mp = pmap_extract_and_hold(map->pmap, va, prot); if (*mp == NULL) pmap_failed = TRUE; else if ((prot & VM_PROT_WRITE) != 0 && (*mp)->dirty != VM_PAGE_BITS_ALL) { /* * Explicitly dirty the physical page. Otherwise, the * caller's changes may go unnoticed because they are * performed through an unmanaged mapping or by a DMA * operation. * * The object lock is not held here. * See vm_page_clear_dirty_mask(). */ vm_page_dirty(*mp); } } if (pmap_failed) { /* * One or more pages could not be held by the pmap. Either no * page was mapped at the specified virtual address or that * mapping had insufficient permissions. Attempt to fault in * and hold these pages. */ for (mp = ma, va = addr; va < end; mp++, va += PAGE_SIZE) if (*mp == NULL && vm_fault_hold(map, va, prot, VM_FAULT_NORMAL, mp) != KERN_SUCCESS) goto error; } return (count); error: for (mp = ma; mp < ma + count; mp++) if (*mp != NULL) { vm_page_lock(*mp); vm_page_unhold(*mp); vm_page_unlock(*mp); } return (-1); } /* * Routine: * vm_fault_copy_entry * Function: * Create new shadow object backing dst_entry with private copy of * all underlying pages. When src_entry is equal to dst_entry, * function implements COW for wired-down map entry. Otherwise, * it forks wired entry into dst_map. * * In/out conditions: * The source and destination maps must be locked for write. * The source map entry must be wired down (or be a sharing map * entry corresponding to a main map entry that is wired down). */ void vm_fault_copy_entry(vm_map_t dst_map, vm_map_t src_map, vm_map_entry_t dst_entry, vm_map_entry_t src_entry, vm_ooffset_t *fork_charge) { vm_object_t backing_object, dst_object, object, src_object; vm_pindex_t dst_pindex, pindex, src_pindex; vm_prot_t access, prot; vm_offset_t vaddr; vm_page_t dst_m; vm_page_t src_m; boolean_t upgrade; #ifdef lint src_map++; #endif /* lint */ upgrade = src_entry == dst_entry; access = prot = dst_entry->protection; src_object = src_entry->object.vm_object; src_pindex = OFF_TO_IDX(src_entry->offset); if (upgrade && (dst_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) { dst_object = src_object; vm_object_reference(dst_object); } else { /* * Create the top-level object for the destination entry. (Doesn't * actually shadow anything - we copy the pages directly.) */ dst_object = vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(dst_entry->end - dst_entry->start)); #if VM_NRESERVLEVEL > 0 dst_object->flags |= OBJ_COLORED; dst_object->pg_color = atop(dst_entry->start); #endif } VM_OBJECT_WLOCK(dst_object); KASSERT(upgrade || dst_entry->object.vm_object == NULL, ("vm_fault_copy_entry: vm_object not NULL")); if (src_object != dst_object) { dst_entry->object.vm_object = dst_object; dst_entry->offset = 0; dst_object->charge = dst_entry->end - dst_entry->start; } if (fork_charge != NULL) { KASSERT(dst_entry->cred == NULL, ("vm_fault_copy_entry: leaked swp charge")); dst_object->cred = curthread->td_ucred; crhold(dst_object->cred); *fork_charge += dst_object->charge; } else if (dst_object->cred == NULL) { KASSERT(dst_entry->cred != NULL, ("no cred for entry %p", dst_entry)); dst_object->cred = dst_entry->cred; dst_entry->cred = NULL; } /* * If not an upgrade, then enter the mappings in the pmap as * read and/or execute accesses. Otherwise, enter them as * write accesses. * * A writeable large page mapping is only created if all of * the constituent small page mappings are modified. Marking * PTEs as modified on inception allows promotion to happen * without taking potentially large number of soft faults. */ if (!upgrade) access &= ~VM_PROT_WRITE; /* * Loop through all of the virtual pages within the entry's * range, copying each page from the source object to the * destination object. Since the source is wired, those pages * must exist. In contrast, the destination is pageable. * Since the destination object does share any backing storage * with the source object, all of its pages must be dirtied, * regardless of whether they can be written. */ for (vaddr = dst_entry->start, dst_pindex = 0; vaddr < dst_entry->end; vaddr += PAGE_SIZE, dst_pindex++) { again: /* * Find the page in the source object, and copy it in. * Because the source is wired down, the page will be * in memory. */ if (src_object != dst_object) VM_OBJECT_RLOCK(src_object); object = src_object; pindex = src_pindex + dst_pindex; while ((src_m = vm_page_lookup(object, pindex)) == NULL && (backing_object = object->backing_object) != NULL) { /* * Unless the source mapping is read-only or * it is presently being upgraded from * read-only, the first object in the shadow * chain should provide all of the pages. In * other words, this loop body should never be * executed when the source mapping is already * read/write. */ KASSERT((src_entry->protection & VM_PROT_WRITE) == 0 || upgrade, ("vm_fault_copy_entry: main object missing page")); VM_OBJECT_RLOCK(backing_object); pindex += OFF_TO_IDX(object->backing_object_offset); if (object != dst_object) VM_OBJECT_RUNLOCK(object); object = backing_object; } KASSERT(src_m != NULL, ("vm_fault_copy_entry: page missing")); if (object != dst_object) { /* * Allocate a page in the destination object. */ dst_m = vm_page_alloc(dst_object, (src_object == dst_object ? src_pindex : 0) + dst_pindex, VM_ALLOC_NORMAL); if (dst_m == NULL) { VM_OBJECT_WUNLOCK(dst_object); VM_OBJECT_RUNLOCK(object); VM_WAIT; VM_OBJECT_WLOCK(dst_object); goto again; } pmap_copy_page(src_m, dst_m); VM_OBJECT_RUNLOCK(object); dst_m->valid = VM_PAGE_BITS_ALL; dst_m->dirty = VM_PAGE_BITS_ALL; } else { dst_m = src_m; if (vm_page_sleep_if_busy(dst_m, "fltupg")) goto again; vm_page_xbusy(dst_m); KASSERT(dst_m->valid == VM_PAGE_BITS_ALL, ("invalid dst page %p", dst_m)); } VM_OBJECT_WUNLOCK(dst_object); /* * Enter it in the pmap. If a wired, copy-on-write * mapping is being replaced by a write-enabled * mapping, then wire that new mapping. */ pmap_enter(dst_map->pmap, vaddr, dst_m, prot, access | (upgrade ? PMAP_ENTER_WIRED : 0), 0); /* * Mark it no longer busy, and put it on the active list. */ VM_OBJECT_WLOCK(dst_object); if (upgrade) { if (src_m != dst_m) { vm_page_lock(src_m); vm_page_unwire(src_m, PQ_INACTIVE); vm_page_unlock(src_m); vm_page_lock(dst_m); vm_page_wire(dst_m); vm_page_unlock(dst_m); } else { KASSERT(dst_m->wire_count > 0, ("dst_m %p is not wired", dst_m)); } } else { vm_page_lock(dst_m); vm_page_activate(dst_m); vm_page_unlock(dst_m); } vm_page_xunbusy(dst_m); } VM_OBJECT_WUNLOCK(dst_object); if (upgrade) { dst_entry->eflags &= ~(MAP_ENTRY_COW | MAP_ENTRY_NEEDS_COPY); vm_object_deallocate(src_object); } } /* * This routine checks around the requested page for other pages that * might be able to be faulted in. This routine brackets the viable * pages for the pages to be paged in. * * Inputs: * m, rbehind, rahead * * Outputs: * marray (array of vm_page_t), reqpage (index of requested page) * * Return value: * number of pages in marray */ static int vm_fault_additional_pages(m, rbehind, rahead, marray, reqpage) vm_page_t m; int rbehind; int rahead; vm_page_t *marray; int *reqpage; { int i,j; vm_object_t object; vm_pindex_t pindex, startpindex, endpindex, tpindex; vm_page_t rtm; int cbehind, cahead; VM_OBJECT_ASSERT_WLOCKED(m->object); object = m->object; pindex = m->pindex; cbehind = cahead = 0; /* * if the requested page is not available, then give up now */ if (!vm_pager_has_page(object, pindex, &cbehind, &cahead)) { return 0; } if ((cbehind == 0) && (cahead == 0)) { *reqpage = 0; marray[0] = m; return 1; } if (rahead > cahead) { rahead = cahead; } if (rbehind > cbehind) { rbehind = cbehind; } /* * scan backward for the read behind pages -- in memory */ if (pindex > 0) { if (rbehind > pindex) { rbehind = pindex; startpindex = 0; } else { startpindex = pindex - rbehind; } if ((rtm = TAILQ_PREV(m, pglist, listq)) != NULL && rtm->pindex >= startpindex) startpindex = rtm->pindex + 1; /* tpindex is unsigned; beware of numeric underflow. */ for (i = 0, tpindex = pindex - 1; tpindex >= startpindex && tpindex < pindex; i++, tpindex--) { rtm = vm_page_alloc(object, tpindex, VM_ALLOC_NORMAL | VM_ALLOC_IFNOTCACHED); if (rtm == NULL) { /* * Shift the allocated pages to the * beginning of the array. */ for (j = 0; j < i; j++) { marray[j] = marray[j + tpindex + 1 - startpindex]; } break; } marray[tpindex - startpindex] = rtm; } } else { startpindex = 0; i = 0; } marray[i] = m; /* page offset of the required page */ *reqpage = i; tpindex = pindex + 1; i++; /* * scan forward for the read ahead pages */ endpindex = tpindex + rahead; if ((rtm = TAILQ_NEXT(m, listq)) != NULL && rtm->pindex < endpindex) endpindex = rtm->pindex; if (endpindex > object->size) endpindex = object->size; for (; tpindex < endpindex; i++, tpindex++) { rtm = vm_page_alloc(object, tpindex, VM_ALLOC_NORMAL | VM_ALLOC_IFNOTCACHED); if (rtm == NULL) { break; } marray[i] = rtm; } /* return number of pages */ return i; } /* * Block entry into the machine-independent layer's page fault handler by * the calling thread. Subsequent calls to vm_fault() by that thread will * return KERN_PROTECTION_FAILURE. Enable machine-dependent handling of * spurious page faults. */ int vm_fault_disable_pagefaults(void) { return (curthread_pflags_set(TDP_NOFAULTING | TDP_RESETSPUR)); } void vm_fault_enable_pagefaults(int save) { curthread_pflags_restore(save); } Index: head/sys/vm/vm_mmap.c =================================================================== --- head/sys/vm/vm_mmap.c (revision 280326) +++ head/sys/vm/vm_mmap.c (revision 280327) @@ -1,1720 +1,1726 @@ /*- * Copyright (c) 1988 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. * * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$ * * @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94 */ /* * Mapped file (mmap) interface to VM */ #include __FBSDID("$FreeBSD$"); #include "opt_compat.h" #include "opt_hwpmc_hooks.h" +#include "opt_vm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef HWPMC_HOOKS #include #endif int old_mlock = 0; SYSCTL_INT(_vm, OID_AUTO, old_mlock, CTLFLAG_RWTUN, &old_mlock, 0, "Do not apply RLIMIT_MEMLOCK on mlockall"); #ifdef MAP_32BIT #define MAP_32BIT_MAX_ADDR ((vm_offset_t)1 << 31) #endif static int vm_mmap_vnode(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, int *, struct vnode *, vm_ooffset_t *, vm_object_t *, boolean_t *); static int vm_mmap_cdev(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, int *, struct cdev *, vm_ooffset_t *, vm_object_t *); static int vm_mmap_shm(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, int *, struct shmfd *, vm_ooffset_t, vm_object_t *); #ifndef _SYS_SYSPROTO_H_ struct sbrk_args { int incr; }; #endif /* * MPSAFE */ /* ARGSUSED */ int sys_sbrk(td, uap) struct thread *td; struct sbrk_args *uap; { /* Not yet implemented */ return (EOPNOTSUPP); } #ifndef _SYS_SYSPROTO_H_ struct sstk_args { int incr; }; #endif /* * MPSAFE */ /* ARGSUSED */ int sys_sstk(td, uap) struct thread *td; struct sstk_args *uap; { /* Not yet implemented */ return (EOPNOTSUPP); } #if defined(COMPAT_43) #ifndef _SYS_SYSPROTO_H_ struct getpagesize_args { int dummy; }; #endif int ogetpagesize(td, uap) struct thread *td; struct getpagesize_args *uap; { /* MP SAFE */ td->td_retval[0] = PAGE_SIZE; return (0); } #endif /* COMPAT_43 */ /* * Memory Map (mmap) system call. Note that the file offset * and address are allowed to be NOT page aligned, though if * the MAP_FIXED flag it set, both must have the same remainder * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not * page-aligned, the actual mapping starts at trunc_page(addr) * and the return value is adjusted up by the page offset. * * Generally speaking, only character devices which are themselves * memory-based, such as a video framebuffer, can be mmap'd. Otherwise * there would be no cache coherency between a descriptor and a VM mapping * both to the same character device. */ #ifndef _SYS_SYSPROTO_H_ struct mmap_args { void *addr; size_t len; int prot; int flags; int fd; long pad; off_t pos; }; #endif /* * MPSAFE */ int sys_mmap(td, uap) struct thread *td; struct mmap_args *uap; { #ifdef HWPMC_HOOKS struct pmckern_map_in pkm; #endif struct file *fp; struct vnode *vp; vm_offset_t addr; vm_size_t size, pageoff; vm_prot_t cap_maxprot, maxprot; void *handle; objtype_t handle_type; int align, error, flags, prot; off_t pos; struct vmspace *vms = td->td_proc->p_vmspace; cap_rights_t rights; addr = (vm_offset_t) uap->addr; size = uap->len; prot = uap->prot; flags = uap->flags; pos = uap->pos; fp = NULL; /* * Ignore old flags that used to be defined but did not do anything. */ flags &= ~(MAP_RESERVED0020 | MAP_RESERVED0040); /* * Enforce the constraints. * Mapping of length 0 is only allowed for old binaries. * Anonymous mapping shall specify -1 as filedescriptor and * zero position for new code. Be nice to ancient a.out * binaries and correct pos for anonymous mapping, since old * ld.so sometimes issues anonymous map requests with non-zero * pos. */ if (!SV_CURPROC_FLAG(SV_AOUT)) { if ((uap->len == 0 && curproc->p_osrel >= P_OSREL_MAP_ANON) || ((flags & MAP_ANON) != 0 && (uap->fd != -1 || pos != 0))) return (EINVAL); } else { if ((flags & MAP_ANON) != 0) pos = 0; } if (flags & MAP_STACK) { if ((uap->fd != -1) || ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) return (EINVAL); flags |= MAP_ANON; pos = 0; } if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE | MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE | MAP_PREFAULT_READ | #ifdef MAP_32BIT MAP_32BIT | #endif MAP_ALIGNMENT_MASK)) != 0) return (EINVAL); if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) return (EINVAL); if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) return (EINVAL); if (prot != PROT_NONE && (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) return (EINVAL); /* * Align the file position to a page boundary, * and save its page offset component. */ pageoff = (pos & PAGE_MASK); pos -= pageoff; /* Adjust size for rounding (on both ends). */ size += pageoff; /* low end... */ size = (vm_size_t) round_page(size); /* hi end */ /* Ensure alignment is at least a page and fits in a pointer. */ align = flags & MAP_ALIGNMENT_MASK; if (align != 0 && align != MAP_ALIGNED_SUPER && (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) return (EINVAL); /* * Check for illegal addresses. Watch out for address wrap... Note * that VM_*_ADDRESS are not constants due to casts (argh). */ if (flags & MAP_FIXED) { /* * The specified address must have the same remainder * as the file offset taken modulo PAGE_SIZE, so it * should be aligned after adjustment by pageoff. */ addr -= pageoff; if (addr & PAGE_MASK) return (EINVAL); /* Address range must be all in user VM space. */ if (addr < vm_map_min(&vms->vm_map) || addr + size > vm_map_max(&vms->vm_map)) return (EINVAL); if (addr + size < addr) return (EINVAL); #ifdef MAP_32BIT if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) return (EINVAL); } else if (flags & MAP_32BIT) { /* * For MAP_32BIT, override the hint if it is too high and * do not bother moving the mapping past the heap (since * the heap is usually above 2GB). */ if (addr + size > MAP_32BIT_MAX_ADDR) addr = 0; #endif } else { /* * XXX for non-fixed mappings where no hint is provided or * the hint would fall in the potential heap space, * place it after the end of the largest possible heap. * * There should really be a pmap call to determine a reasonable * location. */ PROC_LOCK(td->td_proc); if (addr == 0 || (addr >= round_page((vm_offset_t)vms->vm_taddr) && addr < round_page((vm_offset_t)vms->vm_daddr + lim_max(td->td_proc, RLIMIT_DATA)))) addr = round_page((vm_offset_t)vms->vm_daddr + lim_max(td->td_proc, RLIMIT_DATA)); PROC_UNLOCK(td->td_proc); } if (flags & MAP_ANON) { /* * Mapping blank space is trivial. */ handle = NULL; handle_type = OBJT_DEFAULT; maxprot = VM_PROT_ALL; cap_maxprot = VM_PROT_ALL; } else { /* * Mapping file, get fp for validation and don't let the * descriptor disappear on us if we block. Check capability * rights, but also return the maximum rights to be combined * with maxprot later. */ cap_rights_init(&rights, CAP_MMAP); if (prot & PROT_READ) cap_rights_set(&rights, CAP_MMAP_R); if ((flags & MAP_SHARED) != 0) { if (prot & PROT_WRITE) cap_rights_set(&rights, CAP_MMAP_W); } if (prot & PROT_EXEC) cap_rights_set(&rights, CAP_MMAP_X); error = fget_mmap(td, uap->fd, &rights, &cap_maxprot, &fp); if (error != 0) goto done; if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 && td->td_proc->p_osrel >= P_OSREL_MAP_FSTRICT) { error = EINVAL; goto done; } if (fp->f_type == DTYPE_SHM) { handle = fp->f_data; handle_type = OBJT_SWAP; maxprot = VM_PROT_NONE; /* FREAD should always be set. */ if (fp->f_flag & FREAD) maxprot |= VM_PROT_EXECUTE | VM_PROT_READ; if (fp->f_flag & FWRITE) maxprot |= VM_PROT_WRITE; goto map; } if (fp->f_type != DTYPE_VNODE) { error = ENODEV; goto done; } #if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \ defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) /* * POSIX shared-memory objects are defined to have * kernel persistence, and are not defined to support * read(2)/write(2) -- or even open(2). Thus, we can * use MAP_ASYNC to trade on-disk coherence for speed. * The shm_open(3) library routine turns on the FPOSIXSHM * flag to request this behavior. */ if (fp->f_flag & FPOSIXSHM) flags |= MAP_NOSYNC; #endif vp = fp->f_vnode; /* * Ensure that file and memory protections are * compatible. Note that we only worry about * writability if mapping is shared; in this case, * current and max prot are dictated by the open file. * XXX use the vnode instead? Problem is: what * credentials do we use for determination? What if * proc does a setuid? */ if (vp->v_mount != NULL && vp->v_mount->mnt_flag & MNT_NOEXEC) maxprot = VM_PROT_NONE; else maxprot = VM_PROT_EXECUTE; if (fp->f_flag & FREAD) { maxprot |= VM_PROT_READ; } else if (prot & PROT_READ) { error = EACCES; goto done; } /* * If we are sharing potential changes (either via * MAP_SHARED or via the implicit sharing of character * device mappings), and we are trying to get write * permission although we opened it without asking * for it, bail out. */ if ((flags & MAP_SHARED) != 0) { if ((fp->f_flag & FWRITE) != 0) { maxprot |= VM_PROT_WRITE; } else if ((prot & PROT_WRITE) != 0) { error = EACCES; goto done; } } else if (vp->v_type != VCHR || (fp->f_flag & FWRITE) != 0) { maxprot |= VM_PROT_WRITE; cap_maxprot |= VM_PROT_WRITE; } handle = (void *)vp; handle_type = OBJT_VNODE; } map: td->td_fpop = fp; maxprot &= cap_maxprot; /* This relies on VM_PROT_* matching PROT_*. */ error = vm_mmap(&vms->vm_map, &addr, size, prot, maxprot, flags, handle_type, handle, pos); td->td_fpop = NULL; #ifdef HWPMC_HOOKS /* inform hwpmc(4) if an executable is being mapped */ if (error == 0 && handle_type == OBJT_VNODE && (prot & PROT_EXEC)) { pkm.pm_file = handle; pkm.pm_address = (uintptr_t) addr; PMC_CALL_HOOK(td, PMC_FN_MMAP, (void *) &pkm); } #endif if (error == 0) td->td_retval[0] = (register_t) (addr + pageoff); done: if (fp) fdrop(fp, td); return (error); } int freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) { struct mmap_args oargs; oargs.addr = uap->addr; oargs.len = uap->len; oargs.prot = uap->prot; oargs.flags = uap->flags; oargs.fd = uap->fd; oargs.pos = uap->pos; return (sys_mmap(td, &oargs)); } #ifdef COMPAT_43 #ifndef _SYS_SYSPROTO_H_ struct ommap_args { caddr_t addr; int len; int prot; int flags; int fd; long pos; }; #endif int ommap(td, uap) struct thread *td; struct ommap_args *uap; { struct mmap_args nargs; static const char cvtbsdprot[8] = { 0, PROT_EXEC, PROT_WRITE, PROT_EXEC | PROT_WRITE, PROT_READ, PROT_EXEC | PROT_READ, PROT_WRITE | PROT_READ, PROT_EXEC | PROT_WRITE | PROT_READ, }; #define OMAP_ANON 0x0002 #define OMAP_COPY 0x0020 #define OMAP_SHARED 0x0010 #define OMAP_FIXED 0x0100 nargs.addr = uap->addr; nargs.len = uap->len; nargs.prot = cvtbsdprot[uap->prot & 0x7]; #ifdef COMPAT_FREEBSD32 #if defined(__amd64__) if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && nargs.prot != 0) nargs.prot |= PROT_EXEC; #endif #endif nargs.flags = 0; if (uap->flags & OMAP_ANON) nargs.flags |= MAP_ANON; if (uap->flags & OMAP_COPY) nargs.flags |= MAP_COPY; if (uap->flags & OMAP_SHARED) nargs.flags |= MAP_SHARED; else nargs.flags |= MAP_PRIVATE; if (uap->flags & OMAP_FIXED) nargs.flags |= MAP_FIXED; nargs.fd = uap->fd; nargs.pos = uap->pos; return (sys_mmap(td, &nargs)); } #endif /* COMPAT_43 */ #ifndef _SYS_SYSPROTO_H_ struct msync_args { void *addr; size_t len; int flags; }; #endif /* * MPSAFE */ int sys_msync(td, uap) struct thread *td; struct msync_args *uap; { vm_offset_t addr; vm_size_t size, pageoff; int flags; vm_map_t map; int rv; addr = (vm_offset_t) uap->addr; size = uap->len; flags = uap->flags; pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vm_size_t) round_page(size); if (addr + size < addr) return (EINVAL); if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) return (EINVAL); map = &td->td_proc->p_vmspace->vm_map; /* * Clean the pages and interpret the return value. */ rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, (flags & MS_INVALIDATE) != 0); switch (rv) { case KERN_SUCCESS: return (0); case KERN_INVALID_ADDRESS: return (ENOMEM); case KERN_INVALID_ARGUMENT: return (EBUSY); case KERN_FAILURE: return (EIO); default: return (EINVAL); } } #ifndef _SYS_SYSPROTO_H_ struct munmap_args { void *addr; size_t len; }; #endif /* * MPSAFE */ int sys_munmap(td, uap) struct thread *td; struct munmap_args *uap; { #ifdef HWPMC_HOOKS struct pmckern_map_out pkm; vm_map_entry_t entry; #endif vm_offset_t addr; vm_size_t size, pageoff; vm_map_t map; addr = (vm_offset_t) uap->addr; size = uap->len; if (size == 0) return (EINVAL); pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vm_size_t) round_page(size); if (addr + size < addr) return (EINVAL); /* * Check for illegal addresses. Watch out for address wrap... */ map = &td->td_proc->p_vmspace->vm_map; if (addr < vm_map_min(map) || addr + size > vm_map_max(map)) return (EINVAL); vm_map_lock(map); #ifdef HWPMC_HOOKS /* * Inform hwpmc if the address range being unmapped contains * an executable region. */ pkm.pm_address = (uintptr_t) NULL; if (vm_map_lookup_entry(map, addr, &entry)) { for (; entry != &map->header && entry->start < addr + size; entry = entry->next) { if (vm_map_check_protection(map, entry->start, entry->end, VM_PROT_EXECUTE) == TRUE) { pkm.pm_address = (uintptr_t) addr; pkm.pm_size = (size_t) size; break; } } } #endif vm_map_delete(map, addr, addr + size); #ifdef HWPMC_HOOKS /* downgrade the lock to prevent a LOR with the pmc-sx lock */ vm_map_lock_downgrade(map); if (pkm.pm_address != (uintptr_t) NULL) PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); vm_map_unlock_read(map); #else vm_map_unlock(map); #endif /* vm_map_delete returns nothing but KERN_SUCCESS anyway */ return (0); } #ifndef _SYS_SYSPROTO_H_ struct mprotect_args { const void *addr; size_t len; int prot; }; #endif /* * MPSAFE */ int sys_mprotect(td, uap) struct thread *td; struct mprotect_args *uap; { vm_offset_t addr; vm_size_t size, pageoff; vm_prot_t prot; addr = (vm_offset_t) uap->addr; size = uap->len; prot = uap->prot & VM_PROT_ALL; pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vm_size_t) round_page(size); if (addr + size < addr) return (EINVAL); switch (vm_map_protect(&td->td_proc->p_vmspace->vm_map, addr, addr + size, prot, FALSE)) { case KERN_SUCCESS: return (0); case KERN_PROTECTION_FAILURE: return (EACCES); case KERN_RESOURCE_SHORTAGE: return (ENOMEM); } return (EINVAL); } #ifndef _SYS_SYSPROTO_H_ struct minherit_args { void *addr; size_t len; int inherit; }; #endif /* * MPSAFE */ int sys_minherit(td, uap) struct thread *td; struct minherit_args *uap; { vm_offset_t addr; vm_size_t size, pageoff; vm_inherit_t inherit; addr = (vm_offset_t)uap->addr; size = uap->len; inherit = uap->inherit; pageoff = (addr & PAGE_MASK); addr -= pageoff; size += pageoff; size = (vm_size_t) round_page(size); if (addr + size < addr) return (EINVAL); switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, addr + size, inherit)) { case KERN_SUCCESS: return (0); case KERN_PROTECTION_FAILURE: return (EACCES); } return (EINVAL); } #ifndef _SYS_SYSPROTO_H_ struct madvise_args { void *addr; size_t len; int behav; }; #endif /* * MPSAFE */ int sys_madvise(td, uap) struct thread *td; struct madvise_args *uap; { vm_offset_t start, end; vm_map_t map; int flags; /* * Check for our special case, advising the swap pager we are * "immortal." */ if (uap->behav == MADV_PROTECT) { flags = PPROT_SET; return (kern_procctl(td, P_PID, td->td_proc->p_pid, PROC_SPROTECT, &flags)); } /* * Check for illegal behavior */ if (uap->behav < 0 || uap->behav > MADV_CORE) return (EINVAL); /* * Check for illegal addresses. Watch out for address wrap... Note * that VM_*_ADDRESS are not constants due to casts (argh). */ map = &td->td_proc->p_vmspace->vm_map; if ((vm_offset_t)uap->addr < vm_map_min(map) || (vm_offset_t)uap->addr + uap->len > vm_map_max(map)) return (EINVAL); if (((vm_offset_t) uap->addr + uap->len) < (vm_offset_t) uap->addr) return (EINVAL); /* * Since this routine is only advisory, we default to conservative * behavior. */ start = trunc_page((vm_offset_t) uap->addr); end = round_page((vm_offset_t) uap->addr + uap->len); if (vm_map_madvise(map, start, end, uap->behav)) return (EINVAL); return (0); } #ifndef _SYS_SYSPROTO_H_ struct mincore_args { const void *addr; size_t len; char *vec; }; #endif /* * MPSAFE */ int sys_mincore(td, uap) struct thread *td; struct mincore_args *uap; { vm_offset_t addr, first_addr; vm_offset_t end, cend; pmap_t pmap; vm_map_t map; char *vec; int error = 0; int vecindex, lastvecindex; vm_map_entry_t current; vm_map_entry_t entry; vm_object_t object; vm_paddr_t locked_pa; vm_page_t m; vm_pindex_t pindex; int mincoreinfo; unsigned int timestamp; boolean_t locked; /* * Make sure that the addresses presented are valid for user * mode. */ first_addr = addr = trunc_page((vm_offset_t) uap->addr); end = addr + (vm_size_t)round_page(uap->len); map = &td->td_proc->p_vmspace->vm_map; if (end > vm_map_max(map) || end < addr) return (ENOMEM); /* * Address of byte vector */ vec = uap->vec; pmap = vmspace_pmap(td->td_proc->p_vmspace); vm_map_lock_read(map); RestartScan: timestamp = map->timestamp; if (!vm_map_lookup_entry(map, addr, &entry)) { vm_map_unlock_read(map); return (ENOMEM); } /* * Do this on a map entry basis so that if the pages are not * in the current processes address space, we can easily look * up the pages elsewhere. */ lastvecindex = -1; for (current = entry; (current != &map->header) && (current->start < end); current = current->next) { /* * check for contiguity */ if (current->end < end && (entry->next == &map->header || current->next->start > current->end)) { vm_map_unlock_read(map); return (ENOMEM); } /* * ignore submaps (for now) or null objects */ if ((current->eflags & MAP_ENTRY_IS_SUB_MAP) || current->object.vm_object == NULL) continue; /* * limit this scan to the current map entry and the * limits for the mincore call */ if (addr < current->start) addr = current->start; cend = current->end; if (cend > end) cend = end; /* * scan this entry one page at a time */ while (addr < cend) { /* * Check pmap first, it is likely faster, also * it can provide info as to whether we are the * one referencing or modifying the page. */ object = NULL; locked_pa = 0; retry: m = NULL; mincoreinfo = pmap_mincore(pmap, addr, &locked_pa); if (locked_pa != 0) { /* * The page is mapped by this process but not * both accessed and modified. It is also * managed. Acquire the object lock so that * other mappings might be examined. */ m = PHYS_TO_VM_PAGE(locked_pa); if (m->object != object) { if (object != NULL) VM_OBJECT_WUNLOCK(object); object = m->object; locked = VM_OBJECT_TRYWLOCK(object); vm_page_unlock(m); if (!locked) { VM_OBJECT_WLOCK(object); vm_page_lock(m); goto retry; } } else vm_page_unlock(m); KASSERT(m->valid == VM_PAGE_BITS_ALL, ("mincore: page %p is mapped but invalid", m)); } else if (mincoreinfo == 0) { /* * The page is not mapped by this process. If * the object implements managed pages, then * determine if the page is resident so that * the mappings might be examined. */ if (current->object.vm_object != object) { if (object != NULL) VM_OBJECT_WUNLOCK(object); object = current->object.vm_object; VM_OBJECT_WLOCK(object); } if (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP || object->type == OBJT_VNODE) { pindex = OFF_TO_IDX(current->offset + (addr - current->start)); m = vm_page_lookup(object, pindex); if (m == NULL && vm_page_is_cached(object, pindex)) mincoreinfo = MINCORE_INCORE; if (m != NULL && m->valid == 0) m = NULL; if (m != NULL) mincoreinfo = MINCORE_INCORE; } } if (m != NULL) { /* Examine other mappings to the page. */ if (m->dirty == 0 && pmap_is_modified(m)) vm_page_dirty(m); if (m->dirty != 0) mincoreinfo |= MINCORE_MODIFIED_OTHER; /* * The first test for PGA_REFERENCED is an * optimization. The second test is * required because a concurrent pmap * operation could clear the last reference * and set PGA_REFERENCED before the call to * pmap_is_referenced(). */ if ((m->aflags & PGA_REFERENCED) != 0 || pmap_is_referenced(m) || (m->aflags & PGA_REFERENCED) != 0) mincoreinfo |= MINCORE_REFERENCED_OTHER; } if (object != NULL) VM_OBJECT_WUNLOCK(object); /* * subyte may page fault. In case it needs to modify * the map, we release the lock. */ vm_map_unlock_read(map); /* * calculate index into user supplied byte vector */ vecindex = OFF_TO_IDX(addr - first_addr); /* * If we have skipped map entries, we need to make sure that * the byte vector is zeroed for those skipped entries. */ while ((lastvecindex + 1) < vecindex) { ++lastvecindex; error = subyte(vec + lastvecindex, 0); if (error) { error = EFAULT; goto done2; } } /* * Pass the page information to the user */ error = subyte(vec + vecindex, mincoreinfo); if (error) { error = EFAULT; goto done2; } /* * If the map has changed, due to the subyte, the previous * output may be invalid. */ vm_map_lock_read(map); if (timestamp != map->timestamp) goto RestartScan; lastvecindex = vecindex; addr += PAGE_SIZE; } } /* * subyte may page fault. In case it needs to modify * the map, we release the lock. */ vm_map_unlock_read(map); /* * Zero the last entries in the byte vector. */ vecindex = OFF_TO_IDX(end - first_addr); while ((lastvecindex + 1) < vecindex) { ++lastvecindex; error = subyte(vec + lastvecindex, 0); if (error) { error = EFAULT; goto done2; } } /* * If the map has changed, due to the subyte, the previous * output may be invalid. */ vm_map_lock_read(map); if (timestamp != map->timestamp) goto RestartScan; vm_map_unlock_read(map); done2: return (error); } #ifndef _SYS_SYSPROTO_H_ struct mlock_args { const void *addr; size_t len; }; #endif /* * MPSAFE */ int sys_mlock(td, uap) struct thread *td; struct mlock_args *uap; { return (vm_mlock(td->td_proc, td->td_ucred, uap->addr, uap->len)); } int vm_mlock(struct proc *proc, struct ucred *cred, const void *addr0, size_t len) { vm_offset_t addr, end, last, start; vm_size_t npages, size; vm_map_t map; unsigned long nsize; int error; error = priv_check_cred(cred, PRIV_VM_MLOCK, 0); if (error) return (error); addr = (vm_offset_t)addr0; size = len; last = addr + size; start = trunc_page(addr); end = round_page(last); if (last < addr || end < addr) return (EINVAL); npages = atop(end - start); if (npages > vm_page_max_wired) return (ENOMEM); map = &proc->p_vmspace->vm_map; PROC_LOCK(proc); nsize = ptoa(npages + pmap_wired_count(map->pmap)); if (nsize > lim_cur(proc, RLIMIT_MEMLOCK)) { PROC_UNLOCK(proc); return (ENOMEM); } PROC_UNLOCK(proc); if (npages + vm_cnt.v_wire_count > vm_page_max_wired) return (EAGAIN); #ifdef RACCT PROC_LOCK(proc); error = racct_set(proc, RACCT_MEMLOCK, nsize); PROC_UNLOCK(proc); if (error != 0) return (ENOMEM); #endif error = vm_map_wire(map, start, end, VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); #ifdef RACCT if (error != KERN_SUCCESS) { PROC_LOCK(proc); racct_set(proc, RACCT_MEMLOCK, ptoa(pmap_wired_count(map->pmap))); PROC_UNLOCK(proc); } #endif return (error == KERN_SUCCESS ? 0 : ENOMEM); } #ifndef _SYS_SYSPROTO_H_ struct mlockall_args { int how; }; #endif /* * MPSAFE */ int sys_mlockall(td, uap) struct thread *td; struct mlockall_args *uap; { vm_map_t map; int error; map = &td->td_proc->p_vmspace->vm_map; error = priv_check(td, PRIV_VM_MLOCK); if (error) return (error); if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) return (EINVAL); /* * If wiring all pages in the process would cause it to exceed * a hard resource limit, return ENOMEM. */ if (!old_mlock && uap->how & MCL_CURRENT) { PROC_LOCK(td->td_proc); if (map->size > lim_cur(td->td_proc, RLIMIT_MEMLOCK)) { PROC_UNLOCK(td->td_proc); return (ENOMEM); } PROC_UNLOCK(td->td_proc); } #ifdef RACCT PROC_LOCK(td->td_proc); error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); PROC_UNLOCK(td->td_proc); if (error != 0) return (ENOMEM); #endif if (uap->how & MCL_FUTURE) { vm_map_lock(map); vm_map_modflags(map, MAP_WIREFUTURE, 0); vm_map_unlock(map); error = 0; } if (uap->how & MCL_CURRENT) { /* * P1003.1-2001 mandates that all currently mapped pages * will be memory resident and locked (wired) upon return * from mlockall(). vm_map_wire() will wire pages, by * calling vm_fault_wire() for each page in the region. */ error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); error = (error == KERN_SUCCESS ? 0 : EAGAIN); } #ifdef RACCT if (error != KERN_SUCCESS) { PROC_LOCK(td->td_proc); racct_set(td->td_proc, RACCT_MEMLOCK, ptoa(pmap_wired_count(map->pmap))); PROC_UNLOCK(td->td_proc); } #endif return (error); } #ifndef _SYS_SYSPROTO_H_ struct munlockall_args { register_t dummy; }; #endif /* * MPSAFE */ int sys_munlockall(td, uap) struct thread *td; struct munlockall_args *uap; { vm_map_t map; int error; map = &td->td_proc->p_vmspace->vm_map; error = priv_check(td, PRIV_VM_MUNLOCK); if (error) return (error); /* Clear the MAP_WIREFUTURE flag from this vm_map. */ vm_map_lock(map); vm_map_modflags(map, 0, MAP_WIREFUTURE); vm_map_unlock(map); /* Forcibly unwire all pages. */ error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); #ifdef RACCT if (error == KERN_SUCCESS) { PROC_LOCK(td->td_proc); racct_set(td->td_proc, RACCT_MEMLOCK, 0); PROC_UNLOCK(td->td_proc); } #endif return (error); } #ifndef _SYS_SYSPROTO_H_ struct munlock_args { const void *addr; size_t len; }; #endif /* * MPSAFE */ int sys_munlock(td, uap) struct thread *td; struct munlock_args *uap; { vm_offset_t addr, end, last, start; vm_size_t size; #ifdef RACCT vm_map_t map; #endif int error; error = priv_check(td, PRIV_VM_MUNLOCK); if (error) return (error); addr = (vm_offset_t)uap->addr; size = uap->len; last = addr + size; start = trunc_page(addr); end = round_page(last); if (last < addr || end < addr) return (EINVAL); error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); #ifdef RACCT if (error == KERN_SUCCESS) { PROC_LOCK(td->td_proc); map = &td->td_proc->p_vmspace->vm_map; racct_set(td->td_proc, RACCT_MEMLOCK, ptoa(pmap_wired_count(map->pmap))); PROC_UNLOCK(td->td_proc); } #endif return (error == KERN_SUCCESS ? 0 : ENOMEM); } /* * vm_mmap_vnode() * * Helper function for vm_mmap. Perform sanity check specific for mmap * operations on vnodes. * * For VCHR vnodes, the vnode lock is held over the call to * vm_mmap_cdev() to keep vp->v_rdev valid. */ int vm_mmap_vnode(struct thread *td, vm_size_t objsize, vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, boolean_t *writecounted) { struct vattr va; vm_object_t obj; vm_offset_t foff; struct ucred *cred; int error, flags, locktype; cred = td->td_ucred; if ((*maxprotp & VM_PROT_WRITE) && (*flagsp & MAP_SHARED)) locktype = LK_EXCLUSIVE; else locktype = LK_SHARED; if ((error = vget(vp, locktype, td)) != 0) return (error); foff = *foffp; flags = *flagsp; obj = vp->v_object; if (vp->v_type == VREG) { /* * Get the proper underlying object */ if (obj == NULL) { error = EINVAL; goto done; } if (obj->type == OBJT_VNODE && obj->handle != vp) { vput(vp); vp = (struct vnode *)obj->handle; /* * Bypass filesystems obey the mpsafety of the * underlying fs. Tmpfs never bypasses. */ error = vget(vp, locktype, td); if (error != 0) return (error); } if (locktype == LK_EXCLUSIVE) { *writecounted = TRUE; vnode_pager_update_writecount(obj, 0, objsize); } } else if (vp->v_type == VCHR) { error = vm_mmap_cdev(td, objsize, prot, maxprotp, flagsp, vp->v_rdev, foffp, objp); if (error == 0) goto mark_atime; goto done; } else { error = EINVAL; goto done; } if ((error = VOP_GETATTR(vp, &va, cred))) goto done; #ifdef MAC error = mac_vnode_check_mmap(cred, vp, prot, flags); if (error != 0) goto done; #endif if ((flags & MAP_SHARED) != 0) { if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { if (prot & PROT_WRITE) { error = EPERM; goto done; } *maxprotp &= ~VM_PROT_WRITE; } } /* * If it is a regular file without any references * we do not need to sync it. * Adjust object size to be the size of actual file. */ objsize = round_page(va.va_size); if (va.va_nlink == 0) flags |= MAP_NOSYNC; - if (obj->type == OBJT_VNODE) + if (obj->type == OBJT_VNODE) { obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, cred); - else { + if (obj == NULL) { + error = ENOMEM; + goto done; + } + } else { KASSERT(obj->type == OBJT_DEFAULT || obj->type == OBJT_SWAP, ("wrong object type")); - vm_object_reference(obj); - } - if (obj == NULL) { - error = ENOMEM; - goto done; + VM_OBJECT_WLOCK(obj); + vm_object_reference_locked(obj); +#if VM_NRESERVLEVEL > 0 + vm_object_color(obj, 0); +#endif + VM_OBJECT_WUNLOCK(obj); } *objp = obj; *flagsp = flags; mark_atime: vfs_mark_atime(vp, cred); done: if (error != 0 && *writecounted) { *writecounted = FALSE; vnode_pager_update_writecount(obj, objsize, 0); } vput(vp); return (error); } /* * vm_mmap_cdev() * * MPSAFE * * Helper function for vm_mmap. Perform sanity check specific for mmap * operations on cdevs. */ int vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, struct cdev *cdev, vm_ooffset_t *foff, vm_object_t *objp) { vm_object_t obj; struct cdevsw *dsw; int error, flags, ref; flags = *flagsp; dsw = dev_refthread(cdev, &ref); if (dsw == NULL) return (ENXIO); if (dsw->d_flags & D_MMAP_ANON) { dev_relthread(cdev, ref); *maxprotp = VM_PROT_ALL; *flagsp |= MAP_ANON; return (0); } /* * cdevs do not provide private mappings of any kind. */ if ((*maxprotp & VM_PROT_WRITE) == 0 && (prot & PROT_WRITE) != 0) { dev_relthread(cdev, ref); return (EACCES); } if (flags & (MAP_PRIVATE|MAP_COPY)) { dev_relthread(cdev, ref); return (EINVAL); } /* * Force device mappings to be shared. */ flags |= MAP_SHARED; #ifdef MAC_XXX error = mac_cdev_check_mmap(td->td_ucred, cdev, prot); if (error != 0) { dev_relthread(cdev, ref); return (error); } #endif /* * First, try d_mmap_single(). If that is not implemented * (returns ENODEV), fall back to using the device pager. * Note that d_mmap_single() must return a reference to the * object (it needs to bump the reference count of the object * it returns somehow). * * XXX assumes VM_PROT_* == PROT_* */ error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); dev_relthread(cdev, ref); if (error != ENODEV) return (error); obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, td->td_ucred); if (obj == NULL) return (EINVAL); *objp = obj; *flagsp = flags; return (0); } /* * vm_mmap_shm() * * MPSAFE * * Helper function for vm_mmap. Perform sanity check specific for mmap * operations on shm file descriptors. */ int vm_mmap_shm(struct thread *td, vm_size_t objsize, vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, struct shmfd *shmfd, vm_ooffset_t foff, vm_object_t *objp) { int error; if ((*flagsp & MAP_SHARED) != 0 && (*maxprotp & VM_PROT_WRITE) == 0 && (prot & PROT_WRITE) != 0) return (EACCES); #ifdef MAC error = mac_posixshm_check_mmap(td->td_ucred, shmfd, prot, *flagsp); if (error != 0) return (error); #endif error = shm_mmap(shmfd, objsize, foff, objp); if (error) return (error); return (0); } /* * vm_mmap() * * MPSAFE * * Internal version of mmap. Currently used by mmap, exec, and sys5 * shared memory. Handle is either a vnode pointer or NULL for MAP_ANON. */ int vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, vm_prot_t maxprot, int flags, objtype_t handle_type, void *handle, vm_ooffset_t foff) { boolean_t fitit; vm_object_t object = NULL; struct thread *td = curthread; int docow, error, findspace, rv; boolean_t writecounted; if (size == 0) return (0); size = round_page(size); if (map == &td->td_proc->p_vmspace->vm_map) { PROC_LOCK(td->td_proc); if (map->size + size > lim_cur(td->td_proc, RLIMIT_VMEM)) { PROC_UNLOCK(td->td_proc); return (ENOMEM); } if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { PROC_UNLOCK(td->td_proc); return (ENOMEM); } if (!old_mlock && map->flags & MAP_WIREFUTURE) { if (ptoa(pmap_wired_count(map->pmap)) + size > lim_cur(td->td_proc, RLIMIT_MEMLOCK)) { racct_set_force(td->td_proc, RACCT_VMEM, map->size); PROC_UNLOCK(td->td_proc); return (ENOMEM); } error = racct_set(td->td_proc, RACCT_MEMLOCK, ptoa(pmap_wired_count(map->pmap)) + size); if (error != 0) { racct_set_force(td->td_proc, RACCT_VMEM, map->size); PROC_UNLOCK(td->td_proc); return (error); } } PROC_UNLOCK(td->td_proc); } /* * We currently can only deal with page aligned file offsets. * The check is here rather than in the syscall because the * kernel calls this function internally for other mmaping * operations (such as in exec) and non-aligned offsets will * cause pmap inconsistencies...so we want to be sure to * disallow this in all cases. */ if (foff & PAGE_MASK) return (EINVAL); if ((flags & MAP_FIXED) == 0) { fitit = TRUE; *addr = round_page(*addr); } else { if (*addr != trunc_page(*addr)) return (EINVAL); fitit = FALSE; } writecounted = FALSE; /* * Lookup/allocate object. */ switch (handle_type) { case OBJT_DEVICE: error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, handle, &foff, &object); break; case OBJT_VNODE: error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, handle, &foff, &object, &writecounted); break; case OBJT_SWAP: error = vm_mmap_shm(td, size, prot, &maxprot, &flags, handle, foff, &object); break; case OBJT_DEFAULT: if (handle == NULL) { error = 0; break; } /* FALLTHROUGH */ default: error = EINVAL; break; } if (error) return (error); if (flags & MAP_ANON) { object = NULL; docow = 0; /* * Unnamed anonymous regions always start at 0. */ if (handle == 0) foff = 0; } else if (flags & MAP_PREFAULT_READ) docow = MAP_PREFAULT; else docow = MAP_PREFAULT_PARTIAL; if ((flags & (MAP_ANON|MAP_SHARED)) == 0) docow |= MAP_COPY_ON_WRITE; if (flags & MAP_NOSYNC) docow |= MAP_DISABLE_SYNCER; if (flags & MAP_NOCORE) docow |= MAP_DISABLE_COREDUMP; /* Shared memory is also shared with children. */ if (flags & MAP_SHARED) docow |= MAP_INHERIT_SHARE; if (writecounted) docow |= MAP_VN_WRITECOUNT; if (flags & MAP_STACK) { if (object != NULL) return (EINVAL); docow |= MAP_STACK_GROWS_DOWN; } if ((flags & MAP_EXCL) != 0) docow |= MAP_CHECK_EXCL; if (fitit) { if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) findspace = VMFS_SUPER_SPACE; else if ((flags & MAP_ALIGNMENT_MASK) != 0) findspace = VMFS_ALIGNED_SPACE(flags >> MAP_ALIGNMENT_SHIFT); else findspace = VMFS_OPTIMAL_SPACE; rv = vm_map_find(map, object, foff, addr, size, #ifdef MAP_32BIT flags & MAP_32BIT ? MAP_32BIT_MAX_ADDR : #endif 0, findspace, prot, maxprot, docow); } else { rv = vm_map_fixed(map, object, foff, *addr, size, prot, maxprot, docow); } if (rv == KERN_SUCCESS) { /* * If the process has requested that all future mappings * be wired, then heed this. */ if (map->flags & MAP_WIREFUTURE) { vm_map_wire(map, *addr, *addr + size, VM_MAP_WIRE_USER | ((flags & MAP_STACK) ? VM_MAP_WIRE_HOLESOK : VM_MAP_WIRE_NOHOLES)); } } else { /* * If this mapping was accounted for in the vnode's * writecount, then undo that now. */ if (writecounted) vnode_pager_release_writecount(object, 0, size); /* * Lose the object reference. Will destroy the * object if it's an unnamed anonymous mapping * or named anonymous without other references. */ vm_object_deallocate(object); } return (vm_mmap_to_errno(rv)); } /* * Translate a Mach VM return code to zero on success or the appropriate errno * on failure. */ int vm_mmap_to_errno(int rv) { switch (rv) { case KERN_SUCCESS: return (0); case KERN_INVALID_ADDRESS: case KERN_NO_SPACE: return (ENOMEM); case KERN_PROTECTION_FAILURE: return (EACCES); default: return (EINVAL); } } Index: head/sys/vm/vm_object.h =================================================================== --- head/sys/vm/vm_object.h (revision 280326) +++ head/sys/vm/vm_object.h (revision 280327) @@ -1,303 +1,327 @@ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_object.h 8.3 (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. * * $FreeBSD$ */ /* * Virtual memory object module definitions. */ #ifndef _VM_OBJECT_ #define _VM_OBJECT_ #include #include #include #include #include /* * Types defined: * * vm_object_t Virtual memory object. * * The root of cached pages pool is protected by both the per-object lock * and the free pages queue mutex. * On insert in the cache radix trie, the per-object lock is expected * to be already held and the free pages queue mutex will be * acquired during the operation too. * On remove and lookup from the cache radix trie, only the free * pages queue mutex is expected to be locked. * These rules allow for reliably checking for the presence of cached * pages with only the per-object lock held, thereby reducing contention * for the free pages queue mutex. * * List of locks * (c) const until freed * (o) per-object lock * (f) free pages queue mutex * */ struct vm_object { struct rwlock lock; TAILQ_ENTRY(vm_object) object_list; /* list of all objects */ LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */ LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */ TAILQ_HEAD(respgs, vm_page) memq; /* list of resident pages */ struct vm_radix rtree; /* root of the resident page radix trie*/ vm_pindex_t size; /* Object size */ int generation; /* generation ID */ int ref_count; /* How many refs?? */ int shadow_count; /* how many objects that this is a shadow for */ vm_memattr_t memattr; /* default memory attribute for pages */ objtype_t type; /* type of pager */ u_short flags; /* see below */ u_short pg_color; /* (c) color of first page in obj */ u_int paging_in_progress; /* Paging (in or out) so don't collapse or destroy */ int resident_page_count; /* number of resident pages */ struct vm_object *backing_object; /* object that I'm a shadow of */ vm_ooffset_t backing_object_offset;/* Offset in backing object */ TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */ LIST_HEAD(, vm_reserv) rvq; /* list of reservations */ struct vm_radix cache; /* (o + f) root of the cache page radix trie */ void *handle; union { /* * VNode pager * * vnp_size - current size of file */ struct { off_t vnp_size; vm_ooffset_t writemappings; } vnp; /* * Device pager * * devp_pglist - list of allocated pages */ struct { TAILQ_HEAD(, vm_page) devp_pglist; struct cdev_pager_ops *ops; struct cdev *dev; } devp; /* * SG pager * * sgp_pglist - list of allocated pages */ struct { TAILQ_HEAD(, vm_page) sgp_pglist; } sgp; /* * Swap pager * * swp_tmpfs - back-pointer to the tmpfs vnode, * if any, which uses the vm object * as backing store. The handle * cannot be reused for linking, * because the vnode can be * reclaimed and recreated, making * the handle changed and hash-chain * invalid. * * swp_bcount - number of swap 'swblock' metablocks, each * contains up to 16 swapblk assignments. * see vm/swap_pager.h */ struct { void *swp_tmpfs; int swp_bcount; } swp; } un_pager; struct ucred *cred; vm_ooffset_t charge; }; /* * Flags */ #define OBJ_FICTITIOUS 0x0001 /* (c) contains fictitious pages */ #define OBJ_UNMANAGED 0x0002 /* (c) contains unmanaged pages */ #define OBJ_ACTIVE 0x0004 /* active objects */ #define OBJ_DEAD 0x0008 /* dead objects (during rundown) */ #define OBJ_NOSPLIT 0x0010 /* dont split this object */ #define OBJ_PIPWNT 0x0040 /* paging in progress wanted */ #define OBJ_MIGHTBEDIRTY 0x0100 /* object might be dirty, only for vnode */ #define OBJ_TMPFS_NODE 0x0200 /* object belongs to tmpfs VREG node */ #define OBJ_TMPFS_DIRTY 0x0400 /* dirty tmpfs obj */ #define OBJ_COLORED 0x1000 /* pg_color is defined */ #define OBJ_ONEMAPPING 0x2000 /* One USE (a single, non-forked) mapping flag */ #define OBJ_DISCONNECTWNT 0x4000 /* disconnect from vnode wanted */ #define OBJ_TMPFS 0x8000 /* has tmpfs vnode allocated */ #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT) #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT)) #ifdef _KERNEL #define OBJPC_SYNC 0x1 /* sync I/O */ #define OBJPC_INVAL 0x2 /* invalidate */ #define OBJPC_NOSYNC 0x4 /* skip if VPO_NOSYNC */ /* * The following options are supported by vm_object_page_remove(). */ #define OBJPR_CLEANONLY 0x1 /* Don't remove dirty pages. */ #define OBJPR_NOTMAPPED 0x2 /* Don't unmap pages. */ #define OBJPR_NOTWIRED 0x4 /* Don't remove wired pages. */ TAILQ_HEAD(object_q, vm_object); extern struct object_q vm_object_list; /* list of allocated objects */ extern struct mtx vm_object_list_mtx; /* lock for object list and count */ extern struct vm_object kernel_object_store; extern struct vm_object kmem_object_store; #define kernel_object (&kernel_object_store) #define kmem_object (&kmem_object_store) #define VM_OBJECT_ASSERT_LOCKED(object) \ rw_assert(&(object)->lock, RA_LOCKED) #define VM_OBJECT_ASSERT_RLOCKED(object) \ rw_assert(&(object)->lock, RA_RLOCKED) #define VM_OBJECT_ASSERT_WLOCKED(object) \ rw_assert(&(object)->lock, RA_WLOCKED) #define VM_OBJECT_ASSERT_UNLOCKED(object) \ rw_assert(&(object)->lock, RA_UNLOCKED) #define VM_OBJECT_LOCK_DOWNGRADE(object) \ rw_downgrade(&(object)->lock) #define VM_OBJECT_RLOCK(object) \ rw_rlock(&(object)->lock) #define VM_OBJECT_RUNLOCK(object) \ rw_runlock(&(object)->lock) #define VM_OBJECT_SLEEP(object, wchan, pri, wmesg, timo) \ rw_sleep((wchan), &(object)->lock, (pri), (wmesg), (timo)) #define VM_OBJECT_TRYRLOCK(object) \ rw_try_rlock(&(object)->lock) #define VM_OBJECT_TRYWLOCK(object) \ rw_try_wlock(&(object)->lock) #define VM_OBJECT_TRYUPGRADE(object) \ rw_try_upgrade(&(object)->lock) #define VM_OBJECT_WLOCK(object) \ rw_wlock(&(object)->lock) #define VM_OBJECT_WUNLOCK(object) \ rw_wunlock(&(object)->lock) /* * The object must be locked or thread private. */ static __inline void vm_object_set_flag(vm_object_t object, u_short bits) { object->flags |= bits; } +/* + * Conditionally set the object's color, which (1) enables the allocation + * of physical memory reservations for anonymous objects and larger-than- + * superpage-sized named objects and (2) determines the first page offset + * within the object at which a reservation may be allocated. In other + * words, the color determines the alignment of the object with respect + * to the largest superpage boundary. When mapping named objects, like + * files or POSIX shared memory objects, the color should be set to zero + * before a virtual address is selected for the mapping. In contrast, + * for anonymous objects, the color may be set after the virtual address + * is selected. + * + * The object must be locked. + */ +static __inline void +vm_object_color(vm_object_t object, u_short color) +{ + + if ((object->flags & OBJ_COLORED) == 0) { + object->pg_color = color; + object->flags |= OBJ_COLORED; + } +} + void vm_object_clear_flag(vm_object_t object, u_short bits); void vm_object_pip_add(vm_object_t object, short i); void vm_object_pip_subtract(vm_object_t object, short i); void vm_object_pip_wakeup(vm_object_t object); void vm_object_pip_wakeupn(vm_object_t object, short i); void vm_object_pip_wait(vm_object_t object, char *waitid); static __inline boolean_t vm_object_cache_is_empty(vm_object_t object) { return (vm_radix_is_empty(&object->cache)); } vm_object_t vm_object_allocate (objtype_t, vm_pindex_t); boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t, boolean_t); void vm_object_collapse (vm_object_t); void vm_object_deallocate (vm_object_t); void vm_object_destroy (vm_object_t); void vm_object_terminate (vm_object_t); void vm_object_set_writeable_dirty (vm_object_t); void vm_object_init (void); void vm_object_madvise(vm_object_t, vm_pindex_t, vm_pindex_t, int); void vm_object_page_cache(vm_object_t object, vm_pindex_t start, vm_pindex_t end); boolean_t vm_object_page_clean(vm_object_t object, vm_ooffset_t start, vm_ooffset_t end, int flags); void vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int options); boolean_t vm_object_populate(vm_object_t, vm_pindex_t, vm_pindex_t); void vm_object_print(long addr, boolean_t have_addr, long count, char *modif); void vm_object_reference (vm_object_t); void vm_object_reference_locked(vm_object_t); int vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr); void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t); void vm_object_split(vm_map_entry_t); boolean_t vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t, boolean_t); void vm_object_unwire(vm_object_t object, vm_ooffset_t offset, vm_size_t length, uint8_t queue); #endif /* _KERNEL */ #endif /* _VM_OBJECT_ */ Index: head/sys/vm/vnode_pager.c =================================================================== --- head/sys/vm/vnode_pager.c (revision 280326) +++ head/sys/vm/vnode_pager.c (revision 280327) @@ -1,1376 +1,1381 @@ /*- * 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 "opt_vm.h" + #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++; +#if VM_NRESERVLEVEL > 0 + vm_object_color(object, 0); +#endif 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, 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, 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, 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, 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; 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); /* 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); }