/* * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * 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. * * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 * $FreeBSD: src/sys/kern/vfs_subr.c,v 1.249.2.30 2003/04/04 20:35:57 tegge Exp $ * $DragonFly: src/sys/kern/vfs_subr.c,v 1.27 2004/03/07 12:09:04 eirikn Exp $ */ /* * External virtual filesystem routines */ #include "opt_ddb.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 static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); static void insmntque (struct vnode *vp, struct mount *mp); static void vclean (struct vnode *vp, lwkt_tokref_t vlock, int flags, struct thread *td); static unsigned long numvnodes; SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); enum vtype iftovt_tab[16] = { VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, }; int vttoif_tab[9] = { 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFSOCK, S_IFIFO, S_IFMT, }; static TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */ static u_long wantfreevnodes = 25; SYSCTL_INT(_debug, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); static u_long freevnodes = 0; SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); static int reassignbufcalls; SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); static int reassignbufloops; SYSCTL_INT(_vfs, OID_AUTO, reassignbufloops, CTLFLAG_RW, &reassignbufloops, 0, ""); static int reassignbufsortgood; SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortgood, CTLFLAG_RW, &reassignbufsortgood, 0, ""); static int reassignbufsortbad; SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortbad, CTLFLAG_RW, &reassignbufsortbad, 0, ""); static int reassignbufmethod = 1; SYSCTL_INT(_vfs, OID_AUTO, reassignbufmethod, CTLFLAG_RW, &reassignbufmethod, 0, ""); #ifdef ENABLE_VFS_IOOPT int vfs_ioopt = 0; SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); #endif struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); /* mounted fs */ struct lwkt_token mountlist_token; struct lwkt_token mntvnode_token; int nfs_mount_type = -1; static struct lwkt_token mntid_token; static struct lwkt_token vnode_free_list_token; static struct lwkt_token spechash_token; struct nfs_public nfs_pub; /* publicly exported FS */ static vm_zone_t vnode_zone; /* * The workitem queue. */ #define SYNCER_MAXDELAY 32 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ time_t syncdelay = 30; /* max time to delay syncing data */ SYSCTL_INT(_kern, OID_AUTO, syncdelay, CTLFLAG_RW, &syncdelay, 0, "VFS data synchronization delay"); time_t filedelay = 30; /* time to delay syncing files */ SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, "File synchronization delay"); time_t dirdelay = 29; /* time to delay syncing directories */ SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, "Directory synchronization delay"); time_t metadelay = 28; /* time to delay syncing metadata */ SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, "VFS metadata synchronization delay"); static int rushjob; /* number of slots to run ASAP */ static int stat_rush_requests; /* number of times I/O speeded up */ SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); static int syncer_delayno = 0; static long syncer_mask; LIST_HEAD(synclist, vnode); static struct synclist *syncer_workitem_pending; int desiredvnodes; SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, &desiredvnodes, 0, "Maximum number of vnodes"); static int minvnodes; SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, &minvnodes, 0, "Minimum number of vnodes"); static int vnlru_nowhere = 0; SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); static void vfs_free_addrlist (struct netexport *nep); static int vfs_free_netcred (struct radix_node *rn, void *w); static int vfs_hang_addrlist (struct mount *mp, struct netexport *nep, struct export_args *argp); #define VSHOULDFREE(vp) \ (!((vp)->v_flag & (VFREE|VDOOMED)) && \ !(vp)->v_holdcnt && !(vp)->v_usecount && \ (!(vp)->v_object || \ !((vp)->v_object->ref_count || (vp)->v_object->resident_page_count))) #define VMIGHTFREE(vp) \ (((vp)->v_flag & (VFREE|VDOOMED|VXLOCK)) == 0 && \ cache_leaf_test(vp) == 0 && (vp)->v_usecount == 0) #define VSHOULDBUSY(vp) \ (((vp)->v_flag & VFREE) && \ ((vp)->v_holdcnt || (vp)->v_usecount)) static void vbusy(struct vnode *vp); static void vfree(struct vnode *vp); static void vmaybefree(struct vnode *vp); /* * NOTE: the vnode interlock must be held on call. */ static __inline void vmaybefree(struct vnode *vp) { if (VSHOULDFREE(vp)) vfree(vp); } /* * Initialize the vnode management data structures. */ void vntblinit() { /* * Desired vnodes is a result of the physical page count * and the size of kernel's heap. It scales in proportion * to the amount of available physical memory. This can * cause trouble on 64-bit and large memory platforms. */ /* desiredvnodes = maxproc + vmstats.v_page_count / 4; */ desiredvnodes = min(maxproc + vmstats.v_page_count /4, 2 * (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / (5 * (sizeof(struct vm_object) + sizeof(struct vnode)))); minvnodes = desiredvnodes / 4; lwkt_token_init(&mountlist_token); lwkt_token_init(&mntvnode_token); lwkt_token_init(&mntid_token); lwkt_token_init(&spechash_token); TAILQ_INIT(&vnode_free_list); lwkt_token_init(&vnode_free_list_token); vnode_zone = zinit("VNODE", sizeof (struct vnode), 0, 0, 5); /* * Initialize the filesystem syncer. */ syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, &syncer_mask); syncer_maxdelay = syncer_mask + 1; } /* * Mark a mount point as busy. Used to synchronize access and to delay * unmounting. Interlock is not released on failure. */ int vfs_busy(struct mount *mp, int flags, lwkt_tokref_t interlkp, struct thread *td) { int lkflags; if (mp->mnt_kern_flag & MNTK_UNMOUNT) { if (flags & LK_NOWAIT) return (ENOENT); mp->mnt_kern_flag |= MNTK_MWAIT; /* * Since all busy locks are shared except the exclusive * lock granted when unmounting, the only place that a * wakeup needs to be done is at the release of the * exclusive lock at the end of dounmount. * * note: interlkp is a serializer and thus can be safely * held through any sleep */ tsleep((caddr_t)mp, 0, "vfs_busy", 0); return (ENOENT); } lkflags = LK_SHARED | LK_NOPAUSE; if (interlkp) lkflags |= LK_INTERLOCK; if (lockmgr(&mp->mnt_lock, lkflags, interlkp, td)) panic("vfs_busy: unexpected lock failure"); return (0); } /* * Free a busy filesystem. */ void vfs_unbusy(struct mount *mp, struct thread *td) { lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td); } /* * Lookup a filesystem type, and if found allocate and initialize * a mount structure for it. * * Devname is usually updated by mount(8) after booting. */ int vfs_rootmountalloc(char *fstypename, char *devname, struct mount **mpp) { struct thread *td = curthread; /* XXX */ struct vfsconf *vfsp; struct mount *mp; if (fstypename == NULL) return (ENODEV); for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) if (!strcmp(vfsp->vfc_name, fstypename)) break; if (vfsp == NULL) return (ENODEV); mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK); bzero((char *)mp, (u_long)sizeof(struct mount)); lockinit(&mp->mnt_lock, 0, "vfslock", VLKTIMEOUT, LK_NOPAUSE); vfs_busy(mp, LK_NOWAIT, NULL, td); TAILQ_INIT(&mp->mnt_nvnodelist); TAILQ_INIT(&mp->mnt_reservedvnlist); mp->mnt_nvnodelistsize = 0; mp->mnt_vfc = vfsp; mp->mnt_op = vfsp->vfc_vfsops; mp->mnt_flag = MNT_RDONLY; mp->mnt_vnodecovered = NULLVP; vfsp->vfc_refcount++; mp->mnt_iosize_max = DFLTPHYS; mp->mnt_stat.f_type = vfsp->vfc_typenum; mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); mp->mnt_stat.f_mntonname[0] = '/'; mp->mnt_stat.f_mntonname[1] = 0; (void) copystr(devname, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 0); *mpp = mp; return (0); } /* * Find an appropriate filesystem to use for the root. If a filesystem * has not been preselected, walk through the list of known filesystems * trying those that have mountroot routines, and try them until one * works or we have tried them all. */ #ifdef notdef /* XXX JH */ int lite2_vfs_mountroot() { struct vfsconf *vfsp; extern int (*lite2_mountroot) (void); int error; if (lite2_mountroot != NULL) return ((*lite2_mountroot)()); for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { if (vfsp->vfc_mountroot == NULL) continue; if ((error = (*vfsp->vfc_mountroot)()) == 0) return (0); printf("%s_mountroot failed: %d\n", vfsp->vfc_name, error); } return (ENODEV); } #endif /* * Lookup a mount point by filesystem identifier. */ struct mount * vfs_getvfs(fsid) fsid_t *fsid; { struct mount *mp; lwkt_tokref ilock; lwkt_gettoken(&ilock, &mountlist_token); TAILQ_FOREACH(mp, &mountlist, mnt_list) { if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { break; } } lwkt_reltoken(&ilock); return (mp); } /* * Get a new unique fsid. Try to make its val[0] unique, since this value * will be used to create fake device numbers for stat(). Also try (but * not so hard) make its val[0] unique mod 2^16, since some emulators only * support 16-bit device numbers. We end up with unique val[0]'s for the * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. * * Keep in mind that several mounts may be running in parallel. Starting * the search one past where the previous search terminated is both a * micro-optimization and a defense against returning the same fsid to * different mounts. */ void vfs_getnewfsid(mp) struct mount *mp; { static u_int16_t mntid_base; lwkt_tokref ilock; fsid_t tfsid; int mtype; lwkt_gettoken(&ilock, &mntid_token); mtype = mp->mnt_vfc->vfc_typenum; tfsid.val[1] = mtype; mtype = (mtype & 0xFF) << 24; for (;;) { tfsid.val[0] = makeudev(255, mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); mntid_base++; if (vfs_getvfs(&tfsid) == NULL) break; } mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; lwkt_reltoken(&ilock); } /* * Knob to control the precision of file timestamps: * * 0 = seconds only; nanoseconds zeroed. * 1 = seconds and nanoseconds, accurate within 1/HZ. * 2 = seconds and nanoseconds, truncated to microseconds. * >=3 = seconds and nanoseconds, maximum precision. */ enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; static int timestamp_precision = TSP_SEC; SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, ×tamp_precision, 0, ""); /* * Get a current timestamp. */ void vfs_timestamp(tsp) struct timespec *tsp; { struct timeval tv; switch (timestamp_precision) { case TSP_SEC: tsp->tv_sec = time_second; tsp->tv_nsec = 0; break; case TSP_HZ: getnanotime(tsp); break; case TSP_USEC: microtime(&tv); TIMEVAL_TO_TIMESPEC(&tv, tsp); break; case TSP_NSEC: default: nanotime(tsp); break; } } /* * Set vnode attributes to VNOVAL */ void vattr_null(vap) struct vattr *vap; { vap->va_type = VNON; vap->va_size = VNOVAL; vap->va_bytes = VNOVAL; vap->va_mode = VNOVAL; vap->va_nlink = VNOVAL; vap->va_uid = VNOVAL; vap->va_gid = VNOVAL; vap->va_fsid = VNOVAL; vap->va_fileid = VNOVAL; vap->va_blocksize = VNOVAL; vap->va_rdev = VNOVAL; vap->va_atime.tv_sec = VNOVAL; vap->va_atime.tv_nsec = VNOVAL; vap->va_mtime.tv_sec = VNOVAL; vap->va_mtime.tv_nsec = VNOVAL; vap->va_ctime.tv_sec = VNOVAL; vap->va_ctime.tv_nsec = VNOVAL; vap->va_flags = VNOVAL; vap->va_gen = VNOVAL; vap->va_vaflags = 0; } /* * This routine is called when we have too many vnodes. It attempts * to free vnodes and will potentially free vnodes that still * have VM backing store (VM backing store is typically the cause * of a vnode blowout so we want to do this). Therefore, this operation * is not considered cheap. * * A number of conditions may prevent a vnode from being reclaimed. * the buffer cache may have references on the vnode, a directory * vnode may still have references due to the namei cache representing * underlying files, or the vnode may be in active use. It is not * desireable to reuse such vnodes. These conditions may cause the * number of vnodes to reach some minimum value regardless of what * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. */ static int vlrureclaim(struct mount *mp) { struct vnode *vp; lwkt_tokref ilock; lwkt_tokref vlock; int done; int trigger; int usevnodes; int count; /* * Calculate the trigger point, don't allow user * screwups to blow us up. This prevents us from * recycling vnodes with lots of resident pages. We * aren't trying to free memory, we are trying to * free vnodes. */ usevnodes = desiredvnodes; if (usevnodes <= 0) usevnodes = 1; trigger = vmstats.v_page_count * 2 / usevnodes; done = 0; lwkt_gettoken(&ilock, &mntvnode_token); count = mp->mnt_nvnodelistsize / 10 + 1; while (count && (vp = TAILQ_FIRST(&mp->mnt_nvnodelist)) != NULL) { /* * __VNODESCAN__ * * The VP will stick around while we hold mntvnode_token, * at least until we block, so we can safely do an initial * check. But we have to check again after obtaining * the vnode interlock. vp->v_interlock points to stable * storage so it's ok if the vp gets ripped out from * under us while we are blocked. */ if (vp->v_type == VNON || vp->v_type == VBAD || !VMIGHTFREE(vp) || /* critical path opt */ (vp->v_object && vp->v_object->resident_page_count >= trigger) ) { TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist,vp, v_nmntvnodes); --count; continue; } /* * Get the interlock, delay moving the node to the tail so * we don't race against new additions to the mountlist. */ lwkt_gettoken(&vlock, vp->v_interlock); if (TAILQ_FIRST(&mp->mnt_nvnodelist) != vp) { lwkt_reltoken(&vlock); continue; } TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist,vp, v_nmntvnodes); /* * Must check again */ if (vp->v_type == VNON || vp->v_type == VBAD || !VMIGHTFREE(vp) || /* critical path opt */ (vp->v_object && vp->v_object->resident_page_count >= trigger) ) { lwkt_reltoken(&vlock); --count; continue; } vgonel(vp, &vlock, curthread); ++done; --count; } lwkt_reltoken(&ilock); return done; } /* * Attempt to recycle vnodes in a context that is always safe to block. * Calling vlrurecycle() from the bowels of file system code has some * interesting deadlock problems. */ static struct thread *vnlruthread; static int vnlruproc_sig; static void vnlru_proc(void) { struct mount *mp, *nmp; lwkt_tokref ilock; int s; int done; struct thread *td = curthread; EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, td, SHUTDOWN_PRI_FIRST); s = splbio(); for (;;) { kproc_suspend_loop(); if (numvnodes - freevnodes <= desiredvnodes * 9 / 10) { vnlruproc_sig = 0; wakeup(&vnlruproc_sig); tsleep(td, 0, "vlruwt", hz); continue; } done = 0; lwkt_gettoken(&ilock, &mountlist_token); for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { if (vfs_busy(mp, LK_NOWAIT, &ilock, td)) { nmp = TAILQ_NEXT(mp, mnt_list); continue; } done += vlrureclaim(mp); lwkt_gettokref(&ilock); nmp = TAILQ_NEXT(mp, mnt_list); vfs_unbusy(mp, td); } lwkt_reltoken(&ilock); if (done == 0) { vnlru_nowhere++; tsleep(td, 0, "vlrup", hz * 3); } } splx(s); } static struct kproc_desc vnlru_kp = { "vnlru", vnlru_proc, &vnlruthread }; SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &vnlru_kp) /* * Routines having to do with the management of the vnode table. */ extern vop_t **dead_vnodeop_p; /* * Return the next vnode from the free list. */ int getnewvnode(tag, mp, vops, vpp) enum vtagtype tag; struct mount *mp; vop_t **vops; struct vnode **vpp; { int s; struct thread *td = curthread; /* XXX */ struct vnode *vp = NULL; struct vnode *xvp; vm_object_t object; lwkt_tokref ilock; lwkt_tokref vlock; s = splbio(); /* * Try to reuse vnodes if we hit the max. This situation only * occurs in certain large-memory (2G+) situations. We cannot * attempt to directly reclaim vnodes due to nasty recursion * problems. */ while (numvnodes - freevnodes > desiredvnodes) { if (vnlruproc_sig == 0) { vnlruproc_sig = 1; /* avoid unnecessary wakeups */ wakeup(vnlruthread); } tsleep(&vnlruproc_sig, 0, "vlruwk", hz); } /* * Attempt to reuse a vnode already on the free list, allocating * a new vnode if we can't find one or if we have not reached a * good minimum for good LRU performance. */ lwkt_gettoken(&ilock, &vnode_free_list_token); if (freevnodes >= wantfreevnodes && numvnodes >= minvnodes) { int count; for (count = 0; count < freevnodes; count++) { /* * __VNODESCAN__ * * Pull the next vnode off the free list and do some * sanity checks. Note that regardless of how we * block, if freevnodes is non-zero there had better * be something on the list. */ vp = TAILQ_FIRST(&vnode_free_list); if (vp == NULL) panic("getnewvnode: free vnode isn't"); /* * Move the vnode to the end of the list so other * processes do not double-block trying to recycle * the same vnode (as an optimization), then get * the interlock. */ TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); /* * Skip vnodes that are in the process of being * held or referenced. Since the act of adding or * removing a vnode on the freelist requires a token * and may block, the ref count may be adjusted * prior to its addition or removal. */ if (VSHOULDBUSY(vp)) { vp = NULL; continue; } /* * Obtain the vnode interlock and check that the * vnode is still on the free list. * * This normally devolves into a degenerate case so * it is optimal. Loop up if it isn't. Note that * the vnode could be in the middle of being moved * off the free list (the VSHOULDBUSY() check) and * must be skipped if so. */ lwkt_gettoken(&vlock, vp->v_interlock); TAILQ_FOREACH_REVERSE(xvp, &vnode_free_list, freelst, v_freelist) { if (vp == xvp) break; } if (vp != xvp || VSHOULDBUSY(vp)) { vp = NULL; continue; } /* * We now safely own the vnode. If the vnode has * an object do not recycle it if its VM object * has resident pages or references. */ if ((VOP_GETVOBJECT(vp, &object) == 0 && (object->resident_page_count || object->ref_count)) ) { lwkt_reltoken(&vlock); vp = NULL; continue; } /* * We can almost reuse this vnode. But we don't want * to recycle it if the vnode has children in the * namecache because that breaks the namecache's * path element chain. (YYY use nc_refs for the * check?) */ KKASSERT(vp->v_flag & VFREE); TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); if (TAILQ_FIRST(&vp->v_namecache) == NULL || cache_leaf_test(vp) >= 0) { /* ok, we can reuse this vnode */ break; } lwkt_reltoken(&vlock); TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); vp = NULL; } } /* * If vp is non-NULL we hold it's interlock. */ if (vp) { vp->v_flag |= VDOOMED; vp->v_flag &= ~VFREE; freevnodes--; lwkt_reltoken(&ilock); cache_purge(vp); /* YYY may block */ vp->v_lease = NULL; if (vp->v_type != VBAD) { vgonel(vp, &vlock, td); } else { lwkt_reltoken(&vlock); } #ifdef INVARIANTS { int s; if (vp->v_data) panic("cleaned vnode isn't"); s = splbio(); if (vp->v_numoutput) panic("Clean vnode has pending I/O's"); splx(s); } #endif vp->v_flag = 0; vp->v_lastw = 0; vp->v_lasta = 0; vp->v_cstart = 0; vp->v_clen = 0; vp->v_socket = 0; vp->v_writecount = 0; /* XXX */ } else { lwkt_reltoken(&ilock); vp = zalloc(vnode_zone); bzero(vp, sizeof(*vp)); vp->v_interlock = lwkt_token_pool_get(vp); lwkt_token_init(&vp->v_pollinfo.vpi_token); vp->v_dd = vp; cache_purge(vp); TAILQ_INIT(&vp->v_namecache); numvnodes++; } TAILQ_INIT(&vp->v_cleanblkhd); TAILQ_INIT(&vp->v_dirtyblkhd); vp->v_type = VNON; vp->v_tag = tag; vp->v_op = vops; insmntque(vp, mp); *vpp = vp; vp->v_usecount = 1; vp->v_data = 0; splx(s); vfs_object_create(vp, td); return (0); } /* * Move a vnode from one mount queue to another. */ static void insmntque(vp, mp) struct vnode *vp; struct mount *mp; { lwkt_tokref ilock; lwkt_gettoken(&ilock, &mntvnode_token); /* * Delete from old mount point vnode list, if on one. */ if (vp->v_mount != NULL) { KASSERT(vp->v_mount->mnt_nvnodelistsize > 0, ("bad mount point vnode list size")); TAILQ_REMOVE(&vp->v_mount->mnt_nvnodelist, vp, v_nmntvnodes); vp->v_mount->mnt_nvnodelistsize--; } /* * Insert into list of vnodes for the new mount point, if available. */ if ((vp->v_mount = mp) == NULL) { lwkt_reltoken(&ilock); return; } TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); mp->mnt_nvnodelistsize++; lwkt_reltoken(&ilock); } /* * Update outstanding I/O count and do wakeup if requested. */ void vwakeup(bp) struct buf *bp; { struct vnode *vp; bp->b_flags &= ~B_WRITEINPROG; if ((vp = bp->b_vp)) { vp->v_numoutput--; if (vp->v_numoutput < 0) panic("vwakeup: neg numoutput"); if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) { vp->v_flag &= ~VBWAIT; wakeup((caddr_t) &vp->v_numoutput); } } } /* * Flush out and invalidate all buffers associated with a vnode. * Called with the underlying object locked. */ int vinvalbuf(struct vnode *vp, int flags, struct thread *td, int slpflag, int slptimeo) { struct buf *bp; struct buf *nbp, *blist; int s, error; vm_object_t object; lwkt_tokref vlock; if (flags & V_SAVE) { s = splbio(); while (vp->v_numoutput) { vp->v_flag |= VBWAIT; error = tsleep((caddr_t)&vp->v_numoutput, slpflag, "vinvlbuf", slptimeo); if (error) { splx(s); return (error); } } if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { splx(s); if ((error = VOP_FSYNC(vp, MNT_WAIT, td)) != 0) return (error); s = splbio(); if (vp->v_numoutput > 0 || !TAILQ_EMPTY(&vp->v_dirtyblkhd)) panic("vinvalbuf: dirty bufs"); } splx(s); } s = splbio(); for (;;) { blist = TAILQ_FIRST(&vp->v_cleanblkhd); if (!blist) blist = TAILQ_FIRST(&vp->v_dirtyblkhd); if (!blist) break; for (bp = blist; bp; bp = nbp) { nbp = TAILQ_NEXT(bp, b_vnbufs); if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { error = BUF_TIMELOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL, "vinvalbuf", slpflag, slptimeo); if (error == ENOLCK) break; splx(s); return (error); } /* * XXX Since there are no node locks for NFS, I * believe there is a slight chance that a delayed * write will occur while sleeping just above, so * check for it. Note that vfs_bio_awrite expects * buffers to reside on a queue, while VOP_BWRITE and * brelse do not. */ if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && (flags & V_SAVE)) { if (bp->b_vp == vp) { if (bp->b_flags & B_CLUSTEROK) { BUF_UNLOCK(bp); vfs_bio_awrite(bp); } else { bremfree(bp); bp->b_flags |= B_ASYNC; VOP_BWRITE(bp->b_vp, bp); } } else { bremfree(bp); (void) VOP_BWRITE(bp->b_vp, bp); } break; } bremfree(bp); bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF); bp->b_flags &= ~B_ASYNC; brelse(bp); } } /* * Wait for I/O to complete. XXX needs cleaning up. The vnode can * have write I/O in-progress but if there is a VM object then the * VM object can also have read-I/O in-progress. */ do { while (vp->v_numoutput > 0) { vp->v_flag |= VBWAIT; tsleep(&vp->v_numoutput, 0, "vnvlbv", 0); } if (VOP_GETVOBJECT(vp, &object) == 0) { while (object->paging_in_progress) vm_object_pip_sleep(object, "vnvlbx"); } } while (vp->v_numoutput > 0); splx(s); /* * Destroy the copy in the VM cache, too. */ lwkt_gettoken(&vlock, vp->v_interlock); if (VOP_GETVOBJECT(vp, &object) == 0) { vm_object_page_remove(object, 0, 0, (flags & V_SAVE) ? TRUE : FALSE); } lwkt_reltoken(&vlock); if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd)) panic("vinvalbuf: flush failed"); return (0); } /* * Truncate a file's buffer and pages to a specified length. This * is in lieu of the old vinvalbuf mechanism, which performed unneeded * sync activity. */ int vtruncbuf(struct vnode *vp, struct thread *td, off_t length, int blksize) { struct buf *bp; struct buf *nbp; int s, anyfreed; int trunclbn; /* * Round up to the *next* lbn. */ trunclbn = (length + blksize - 1) / blksize; s = splbio(); restart: anyfreed = 1; for (;anyfreed;) { anyfreed = 0; for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { nbp = TAILQ_NEXT(bp, b_vnbufs); if (bp->b_lblkno >= trunclbn) { if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); goto restart; } else { bremfree(bp); bp->b_flags |= (B_INVAL | B_RELBUF); bp->b_flags &= ~B_ASYNC; brelse(bp); anyfreed = 1; } if (nbp && (((nbp->b_xflags & BX_VNCLEAN) == 0) || (nbp->b_vp != vp) || (nbp->b_flags & B_DELWRI))) { goto restart; } } } for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { nbp = TAILQ_NEXT(bp, b_vnbufs); if (bp->b_lblkno >= trunclbn) { if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); goto restart; } else { bremfree(bp); bp->b_flags |= (B_INVAL | B_RELBUF); bp->b_flags &= ~B_ASYNC; brelse(bp); anyfreed = 1; } if (nbp && (((nbp->b_xflags & BX_VNDIRTY) == 0) || (nbp->b_vp != vp) || (nbp->b_flags & B_DELWRI) == 0)) { goto restart; } } } } if (length > 0) { restartsync: for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { nbp = TAILQ_NEXT(bp, b_vnbufs); if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) { if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); goto restart; } else { bremfree(bp); if (bp->b_vp == vp) { bp->b_flags |= B_ASYNC; } else { bp->b_flags &= ~B_ASYNC; } VOP_BWRITE(bp->b_vp, bp); } goto restartsync; } } } while (vp->v_numoutput > 0) { vp->v_flag |= VBWAIT; tsleep(&vp->v_numoutput, 0, "vbtrunc", 0); } splx(s); vnode_pager_setsize(vp, length); return (0); } /* * Associate a buffer with a vnode. */ void bgetvp(vp, bp) struct vnode *vp; struct buf *bp; { int s; KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); vhold(vp); bp->b_vp = vp; bp->b_dev = vn_todev(vp); /* * Insert onto list for new vnode. */ s = splbio(); bp->b_xflags |= BX_VNCLEAN; bp->b_xflags &= ~BX_VNDIRTY; TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); splx(s); } /* * Disassociate a buffer from a vnode. */ void brelvp(bp) struct buf *bp; { struct vnode *vp; struct buflists *listheadp; int s; KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); /* * Delete from old vnode list, if on one. */ vp = bp->b_vp; s = splbio(); if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { if (bp->b_xflags & BX_VNDIRTY) listheadp = &vp->v_dirtyblkhd; else listheadp = &vp->v_cleanblkhd; TAILQ_REMOVE(listheadp, bp, b_vnbufs); bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); } if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) { vp->v_flag &= ~VONWORKLST; LIST_REMOVE(vp, v_synclist); } splx(s); bp->b_vp = (struct vnode *) 0; vdrop(vp); } /* * The workitem queue. * * It is useful to delay writes of file data and filesystem metadata * for tens of seconds so that quickly created and deleted files need * not waste disk bandwidth being created and removed. To realize this, * we append vnodes to a "workitem" queue. When running with a soft * updates implementation, most pending metadata dependencies should * not wait for more than a few seconds. Thus, mounted on block devices * are delayed only about a half the time that file data is delayed. * Similarly, directory updates are more critical, so are only delayed * about a third the time that file data is delayed. Thus, there are * SYNCER_MAXDELAY queues that are processed round-robin at a rate of * one each second (driven off the filesystem syncer process). The * syncer_delayno variable indicates the next queue that is to be processed. * Items that need to be processed soon are placed in this queue: * * syncer_workitem_pending[syncer_delayno] * * A delay of fifteen seconds is done by placing the request fifteen * entries later in the queue: * * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] * */ /* * Add an item to the syncer work queue. */ static void vn_syncer_add_to_worklist(struct vnode *vp, int delay) { int s, slot; s = splbio(); if (vp->v_flag & VONWORKLST) { LIST_REMOVE(vp, v_synclist); } if (delay > syncer_maxdelay - 2) delay = syncer_maxdelay - 2; slot = (syncer_delayno + delay) & syncer_mask; LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist); vp->v_flag |= VONWORKLST; splx(s); } struct thread *updatethread; static void sched_sync (void); static struct kproc_desc up_kp = { "syncer", sched_sync, &updatethread }; SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp) /* * System filesystem synchronizer daemon. */ void sched_sync(void) { struct synclist *slp; struct vnode *vp; long starttime; int s; struct thread *td = curthread; EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, td, SHUTDOWN_PRI_LAST); for (;;) { kproc_suspend_loop(); starttime = time_second; /* * Push files whose dirty time has expired. Be careful * of interrupt race on slp queue. */ s = splbio(); slp = &syncer_workitem_pending[syncer_delayno]; syncer_delayno += 1; if (syncer_delayno == syncer_maxdelay) syncer_delayno = 0; splx(s); while ((vp = LIST_FIRST(slp)) != NULL) { if (VOP_ISLOCKED(vp, NULL) == 0) { vn_lock(vp, NULL, LK_EXCLUSIVE | LK_RETRY, td); (void) VOP_FSYNC(vp, MNT_LAZY, td); VOP_UNLOCK(vp, NULL, 0, td); } s = splbio(); if (LIST_FIRST(slp) == vp) { /* * Note: v_tag VT_VFS vps can remain on the * worklist too with no dirty blocks, but * since sync_fsync() moves it to a different * slot we are safe. */ if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && !vn_isdisk(vp, NULL)) panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag); /* * Put us back on the worklist. The worklist * routine will remove us from our current * position and then add us back in at a later * position. */ vn_syncer_add_to_worklist(vp, syncdelay); } splx(s); } /* * Do soft update processing. */ if (bioops.io_sync) (*bioops.io_sync)(NULL); /* * The variable rushjob allows the kernel to speed up the * processing of the filesystem syncer process. A rushjob * value of N tells the filesystem syncer to process the next * N seconds worth of work on its queue ASAP. Currently rushjob * is used by the soft update code to speed up the filesystem * syncer process when the incore state is getting so far * ahead of the disk that the kernel memory pool is being * threatened with exhaustion. */ if (rushjob > 0) { rushjob -= 1; continue; } /* * If it has taken us less than a second to process the * current work, then wait. Otherwise start right over * again. We can still lose time if any single round * takes more than two seconds, but it does not really * matter as we are just trying to generally pace the * filesystem activity. */ if (time_second == starttime) tsleep(&lbolt, 0, "syncer", 0); } } /* * Request the syncer daemon to speed up its work. * We never push it to speed up more than half of its * normal turn time, otherwise it could take over the cpu. * * YYY wchan field protected by the BGL. */ int speedup_syncer() { crit_enter(); if (updatethread->td_wchan == &lbolt) { /* YYY */ unsleep(updatethread); lwkt_schedule(updatethread); } crit_exit(); if (rushjob < syncdelay / 2) { rushjob += 1; stat_rush_requests += 1; return (1); } return(0); } /* * Associate a p-buffer with a vnode. * * Also sets B_PAGING flag to indicate that vnode is not fully associated * with the buffer. i.e. the bp has not been linked into the vnode or * ref-counted. */ void pbgetvp(vp, bp) struct vnode *vp; struct buf *bp; { KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); bp->b_vp = vp; bp->b_flags |= B_PAGING; bp->b_dev = vn_todev(vp); } /* * Disassociate a p-buffer from a vnode. */ void pbrelvp(bp) struct buf *bp; { KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); /* XXX REMOVE ME */ if (TAILQ_NEXT(bp, b_vnbufs) != NULL) { panic( "relpbuf(): b_vp was probably reassignbuf()d %p %x", bp, (int)bp->b_flags ); } bp->b_vp = (struct vnode *) 0; bp->b_flags &= ~B_PAGING; } void pbreassignbuf(bp, newvp) struct buf *bp; struct vnode *newvp; { if ((bp->b_flags & B_PAGING) == 0) { panic( "pbreassignbuf() on non phys bp %p", bp ); } bp->b_vp = newvp; } /* * Reassign a buffer from one vnode to another. * Used to assign file specific control information * (indirect blocks) to the vnode to which they belong. */ void reassignbuf(bp, newvp) struct buf *bp; struct vnode *newvp; { struct buflists *listheadp; int delay; int s; if (newvp == NULL) { printf("reassignbuf: NULL"); return; } ++reassignbufcalls; /* * B_PAGING flagged buffers cannot be reassigned because their vp * is not fully linked in. */ if (bp->b_flags & B_PAGING) panic("cannot reassign paging buffer"); s = splbio(); /* * Delete from old vnode list, if on one. */ if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { if (bp->b_xflags & BX_VNDIRTY) listheadp = &bp->b_vp->v_dirtyblkhd; else listheadp = &bp->b_vp->v_cleanblkhd; TAILQ_REMOVE(listheadp, bp, b_vnbufs); bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); if (bp->b_vp != newvp) { vdrop(bp->b_vp); bp->b_vp = NULL; /* for clarification */ } } /* * If dirty, put on list of dirty buffers; otherwise insert onto list * of clean buffers. */ if (bp->b_flags & B_DELWRI) { struct buf *tbp; listheadp = &newvp->v_dirtyblkhd; if ((newvp->v_flag & VONWORKLST) == 0) { switch (newvp->v_type) { case VDIR: delay = dirdelay; break; case VCHR: case VBLK: if (newvp->v_specmountpoint != NULL) { delay = metadelay; break; } /* fall through */ default: delay = filedelay; } vn_syncer_add_to_worklist(newvp, delay); } bp->b_xflags |= BX_VNDIRTY; tbp = TAILQ_FIRST(listheadp); if (tbp == NULL || bp->b_lblkno == 0 || (bp->b_lblkno > 0 && tbp->b_lblkno < 0) || (bp->b_lblkno > 0 && bp->b_lblkno < tbp->b_lblkno)) { TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); ++reassignbufsortgood; } else if (bp->b_lblkno < 0) { TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); ++reassignbufsortgood; } else if (reassignbufmethod == 1) { /* * New sorting algorithm, only handle sequential case, * otherwise append to end (but before metadata) */ if ((tbp = gbincore(newvp, bp->b_lblkno - 1)) != NULL && (tbp->b_xflags & BX_VNDIRTY)) { /* * Found the best place to insert the buffer */ TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); ++reassignbufsortgood; } else { /* * Missed, append to end, but before meta-data. * We know that the head buffer in the list is * not meta-data due to prior conditionals. * * Indirect effects: NFS second stage write * tends to wind up here, giving maximum * distance between the unstable write and the * commit rpc. */ tbp = TAILQ_LAST(listheadp, buflists); while (tbp && tbp->b_lblkno < 0) tbp = TAILQ_PREV(tbp, buflists, b_vnbufs); TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); ++reassignbufsortbad; } } else { /* * Old sorting algorithm, scan queue and insert */ struct buf *ttbp; while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) && (ttbp->b_lblkno < bp->b_lblkno)) { ++reassignbufloops; tbp = ttbp; } TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); } } else { bp->b_xflags |= BX_VNCLEAN; TAILQ_INSERT_TAIL(&newvp->v_cleanblkhd, bp, b_vnbufs); if ((newvp->v_flag & VONWORKLST) && TAILQ_EMPTY(&newvp->v_dirtyblkhd)) { newvp->v_flag &= ~VONWORKLST; LIST_REMOVE(newvp, v_synclist); } } if (bp->b_vp != newvp) { bp->b_vp = newvp; vhold(bp->b_vp); } splx(s); } /* * Create a vnode for a block device. * Used for mounting the root file system. */ int bdevvp(dev, vpp) dev_t dev; struct vnode **vpp; { struct vnode *vp; struct vnode *nvp; int error; if (dev == NODEV) { *vpp = NULLVP; return (ENXIO); } error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp); if (error) { *vpp = NULLVP; return (error); } vp = nvp; vp->v_type = VBLK; addalias(vp, dev); *vpp = vp; return (0); } /* * Add a vnode to the alias list hung off the dev_t. * * The reason for this gunk is that multiple vnodes can reference * the same physical device, so checking vp->v_usecount to see * how many users there are is inadequate; the v_usecount for * the vnodes need to be accumulated. vcount() does that. */ void addaliasu(struct vnode *nvp, udev_t nvp_rdev) { dev_t dev; if (nvp->v_type != VBLK && nvp->v_type != VCHR) panic("addaliasu on non-special vnode"); dev = udev2dev(nvp_rdev, nvp->v_type == VBLK ? 1 : 0); if (dev != NODEV) { nvp->v_rdev = dev; addalias(nvp, dev); } else nvp->v_rdev = NULL; } void addalias(struct vnode *nvp, dev_t dev) { lwkt_tokref ilock; if (nvp->v_type != VBLK && nvp->v_type != VCHR) panic("addalias on non-special vnode"); nvp->v_rdev = dev; lwkt_gettoken(&ilock, &spechash_token); SLIST_INSERT_HEAD(&dev->si_hlist, nvp, v_specnext); lwkt_reltoken(&ilock); } /* * Grab a particular vnode from the free list, increment its * reference count and lock it. The vnode lock bit is set if the * vnode is being eliminated in vgone. The process is awakened * when the transition is completed, and an error returned to * indicate that the vnode is no longer usable (possibly having * been changed to a new file system type). * * This code is very sensitive. We are depending on the vnode interlock * to be maintained through to the vn_lock() call, which means that we * cannot block which means that we cannot call vbusy() until after vn_lock(). * If the interlock is not maintained, the VXLOCK check will not properly * interlock against a vclean()'s LK_DRAIN operation on the lock. */ int vget(struct vnode *vp, lwkt_tokref_t vlock, int flags, thread_t td) { int error; lwkt_tokref vvlock; /* * We need the interlock to safely modify the v_ fields. ZZZ it is * only legal to pass (1) the vnode's interlock and (2) only pass * NULL w/o LK_INTERLOCK if the vnode is *ALREADY* referenced or * held. */ if ((flags & LK_INTERLOCK) == 0) { lwkt_gettoken(&vvlock, vp->v_interlock); vlock = &vvlock; } /* * If the vnode is in the process of being cleaned out for * another use, we wait for the cleaning to finish and then * return failure. Cleaning is determined by checking that * the VXLOCK flag is set. It is possible for the vnode to be * self-referenced during the cleaning operation. */ if (vp->v_flag & VXLOCK) { if (vp->v_vxthread == curthread) { #if 0 /* this can now occur in normal operation */ log(LOG_INFO, "VXLOCK interlock avoided\n"); #endif } else { vp->v_flag |= VXWANT; lwkt_reltoken(vlock); tsleep((caddr_t)vp, 0, "vget", 0); return (ENOENT); } } /* * Bump v_usecount to prevent the vnode from being recycled. The * usecount needs to be bumped before we successfully get our lock. */ vp->v_usecount++; if (flags & LK_TYPE_MASK) { if ((error = vn_lock(vp, vlock, flags | LK_INTERLOCK, td)) != 0) { /* * must expand vrele here because we do not want * to call VOP_INACTIVE if the reference count * drops back to zero since it was never really * active. We must remove it from the free list * before sleeping so that multiple processes do * not try to recycle it. */ lwkt_gettokref(vlock); vp->v_usecount--; vmaybefree(vp); lwkt_reltoken(vlock); } return (error); } if (VSHOULDBUSY(vp)) vbusy(vp); /* interlock must be held on call */ lwkt_reltoken(vlock); return (0); } void vref(struct vnode *vp) { vp->v_usecount++; /* XXX MP */ } /* * Vnode put/release. * If count drops to zero, call inactive routine and return to freelist. */ void vrele(struct vnode *vp) { struct thread *td = curthread; /* XXX */ lwkt_tokref vlock; KASSERT(vp != NULL, ("vrele: null vp")); lwkt_gettoken(&vlock, vp->v_interlock); if (vp->v_usecount > 1) { vp->v_usecount--; lwkt_reltoken(&vlock); return; } if (vp->v_usecount == 1) { vp->v_usecount--; /* * We must call VOP_INACTIVE with the node locked and the * usecount 0. If we are doing a vpu, the node is already * locked, but, in the case of vrele, we must explicitly lock * the vnode before calling VOP_INACTIVE. */ if (vn_lock(vp, NULL, LK_EXCLUSIVE, td) == 0) VOP_INACTIVE(vp, td); vmaybefree(vp); lwkt_reltoken(&vlock); } else { #ifdef DIAGNOSTIC vprint("vrele: negative ref count", vp); #endif lwkt_reltoken(&vlock); panic("vrele: negative ref cnt"); } } void vput(struct vnode *vp) { struct thread *td = curthread; /* XXX */ lwkt_tokref vlock; KASSERT(vp != NULL, ("vput: null vp")); lwkt_gettoken(&vlock, vp->v_interlock); if (vp->v_usecount > 1) { vp->v_usecount--; VOP_UNLOCK(vp, &vlock, LK_INTERLOCK, td); return; } if (vp->v_usecount == 1) { vp->v_usecount--; /* * We must call VOP_INACTIVE with the node locked. * If we are doing a vpu, the node is already locked, * so we just need to release the vnode mutex. */ VOP_INACTIVE(vp, td); vmaybefree(vp); lwkt_reltoken(&vlock); } else { #ifdef DIAGNOSTIC vprint("vput: negative ref count", vp); #endif lwkt_reltoken(&vlock); panic("vput: negative ref cnt"); } } /* * Somebody doesn't want the vnode recycled. ZZZ vnode interlock should * be held but isn't. */ void vhold(vp) struct vnode *vp; { int s; s = splbio(); vp->v_holdcnt++; if (VSHOULDBUSY(vp)) vbusy(vp); /* interlock must be held on call */ splx(s); } /* * One less who cares about this vnode. */ void vdrop(vp) struct vnode *vp; { lwkt_tokref vlock; lwkt_gettoken(&vlock, vp->v_interlock); if (vp->v_holdcnt <= 0) panic("vdrop: holdcnt"); vp->v_holdcnt--; vmaybefree(vp); lwkt_reltoken(&vlock); } int vmntvnodescan( struct mount *mp, int (*fastfunc)(struct mount *mp, struct vnode *vp, void *data), int (*slowfunc)(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data), void *data ) { lwkt_tokref ilock; lwkt_tokref vlock; struct vnode *pvp; struct vnode *vp; int r = 0; /* * Scan the vnodes on the mount's vnode list. Use a placemarker */ pvp = zalloc(vnode_zone); pvp->v_flag |= VPLACEMARKER; lwkt_gettoken(&ilock, &mntvnode_token); TAILQ_INSERT_HEAD(&mp->mnt_nvnodelist, pvp, v_nmntvnodes); while ((vp = TAILQ_NEXT(pvp, v_nmntvnodes)) != NULL) { /* * Move the placemarker and skip other placemarkers we * encounter. The nothing can get in our way so the * mount point on the vp must be valid. */ TAILQ_REMOVE(&mp->mnt_nvnodelist, pvp, v_nmntvnodes); TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, pvp, v_nmntvnodes); if (vp->v_flag & VPLACEMARKER) continue; KKASSERT(vp->v_mount == mp); /* * Quick test */ if (fastfunc) { if ((r = fastfunc(mp, vp, data)) < 0) continue; if (r) break; } /* * Get the vnodes interlock and make sure it is still on the * mount list. Skip it if it has moved (we may encounter it * later). Then do the with-interlock test. The callback * is responsible for releasing the vnode interlock. * * The interlock is type-stable. */ if (slowfunc) { lwkt_gettoken(&vlock, vp->v_interlock); if (vp != TAILQ_PREV(pvp, vnodelst, v_nmntvnodes)) { printf("vmntvnodescan (debug info only): f=%p vp=%p vnode ripped out from under us\n", slowfunc, vp); lwkt_reltoken(&vlock); continue; } if ((r = slowfunc(mp, vp, &vlock, data)) != 0) { KKASSERT(lwkt_havetokref(&vlock) == 0); break; } KKASSERT(lwkt_havetokref(&vlock) == 0); } } TAILQ_REMOVE(&mp->mnt_nvnodelist, pvp, v_nmntvnodes); zfree(vnode_zone, pvp); lwkt_reltoken(&ilock); return(r); } /* * Remove any vnodes in the vnode table belonging to mount point mp. * * If FORCECLOSE is not specified, there should not be any active ones, * return error if any are found (nb: this is a user error, not a * system error). If FORCECLOSE is specified, detach any active vnodes * that are found. * * If WRITECLOSE is set, only flush out regular file vnodes open for * writing. * * SKIPSYSTEM causes any vnodes marked VSYSTEM to be skipped. * * `rootrefs' specifies the base reference count for the root vnode * of this filesystem. The root vnode is considered busy if its * v_usecount exceeds this value. On a successful return, vflush() * will call vrele() on the root vnode exactly rootrefs times. * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must * be zero. */ #ifdef DIAGNOSTIC static int busyprt = 0; /* print out busy vnodes */ SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); #endif static int vflush_scan(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data); struct vflush_info { int flags; int busy; thread_t td; }; int vflush(mp, rootrefs, flags) struct mount *mp; int rootrefs; int flags; { struct thread *td = curthread; /* XXX */ struct vnode *rootvp = NULL; int error; lwkt_tokref vlock; struct vflush_info vflush_info; if (rootrefs > 0) { KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, ("vflush: bad args")); /* * Get the filesystem root vnode. We can vput() it * immediately, since with rootrefs > 0, it won't go away. */ if ((error = VFS_ROOT(mp, &rootvp)) != 0) return (error); vput(rootvp); } vflush_info.busy = 0; vflush_info.flags = flags; vflush_info.td = td; vmntvnodescan(mp, NULL, vflush_scan, &vflush_info); if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { /* * If just the root vnode is busy, and if its refcount * is equal to `rootrefs', then go ahead and kill it. */ lwkt_gettoken(&vlock, rootvp->v_interlock); KASSERT(vflush_info.busy > 0, ("vflush: not busy")); KASSERT(rootvp->v_usecount >= rootrefs, ("vflush: rootrefs")); if (vflush_info.busy == 1 && rootvp->v_usecount == rootrefs) { vgonel(rootvp, &vlock, td); vflush_info.busy = 0; } else { lwkt_reltoken(&vlock); } } if (vflush_info.busy) return (EBUSY); for (; rootrefs > 0; rootrefs--) vrele(rootvp); return (0); } /* * The scan callback is made with an interlocked vnode. */ static int vflush_scan(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data) { struct vflush_info *info = data; struct vattr vattr; /* * Skip over a vnodes marked VSYSTEM. */ if ((info->flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) { lwkt_reltoken(vlock); return(0); } /* * If WRITECLOSE is set, flush out unlinked but still open * files (even if open only for reading) and regular file * vnodes open for writing. */ if ((info->flags & WRITECLOSE) && (vp->v_type == VNON || (VOP_GETATTR(vp, &vattr, info->td) == 0 && vattr.va_nlink > 0)) && (vp->v_writecount == 0 || vp->v_type != VREG)) { lwkt_reltoken(vlock); return(0); } /* * With v_usecount == 0, all we need to do is clear out the * vnode data structures and we are done. */ if (vp->v_usecount == 0) { vgonel(vp, vlock, info->td); return(0); } /* * If FORCECLOSE is set, forcibly close the vnode. For block * or character devices, revert to an anonymous device. For * all other files, just kill them. */ if (info->flags & FORCECLOSE) { if (vp->v_type != VBLK && vp->v_type != VCHR) { vgonel(vp, vlock, info->td); } else { vclean(vp, vlock, 0, info->td); vp->v_op = spec_vnodeop_p; insmntque(vp, (struct mount *) 0); } return(0); } #ifdef DIAGNOSTIC if (busyprt) vprint("vflush: busy vnode", vp); #endif lwkt_reltoken(vlock); ++info->busy; return(0); } /* * Disassociate the underlying file system from a vnode. */ static void vclean(struct vnode *vp, lwkt_tokref_t vlock, int flags, struct thread *td) { int active; /* * Check to see if the vnode is in use. If so we have to reference it * before we clean it out so that its count cannot fall to zero and * generate a race against ourselves to recycle it. */ if ((active = vp->v_usecount)) vp->v_usecount++; /* * Prevent the vnode from being recycled or brought into use while we * clean it out. */ if (vp->v_flag & VXLOCK) panic("vclean: deadlock"); vp->v_flag |= VXLOCK; vp->v_vxthread = curthread; /* * Even if the count is zero, the VOP_INACTIVE routine may still * have the object locked while it cleans it out. The VOP_LOCK * ensures that the VOP_INACTIVE routine is done with its work. * For active vnodes, it ensures that no other activity can * occur while the underlying object is being cleaned out. * * NOTE: we continue to hold the vnode interlock through to the * end of vclean(). */ VOP_LOCK(vp, NULL, LK_DRAIN, td); /* * Clean out any buffers associated with the vnode. */ vinvalbuf(vp, V_SAVE, td, 0, 0); VOP_DESTROYVOBJECT(vp); /* * If purging an active vnode, it must be closed and * deactivated before being reclaimed. Note that the * VOP_INACTIVE will unlock the vnode. */ if (active) { if (flags & DOCLOSE) VOP_CLOSE(vp, FNONBLOCK, td); VOP_INACTIVE(vp, td); } else { /* * Any other processes trying to obtain this lock must first * wait for VXLOCK to clear, then call the new lock operation. */ VOP_UNLOCK(vp, NULL, 0, td); } /* * Reclaim the vnode. */ if (VOP_RECLAIM(vp, td)) panic("vclean: cannot reclaim"); if (active) { /* * Inline copy of vrele() since VOP_INACTIVE * has already been called. */ if (--vp->v_usecount <= 0) { #ifdef DIAGNOSTIC if (vp->v_usecount < 0 || vp->v_writecount != 0) { vprint("vclean: bad ref count", vp); panic("vclean: ref cnt"); } #endif vfree(vp); } } cache_purge(vp); vp->v_vnlock = NULL; vmaybefree(vp); /* * Done with purge, notify sleepers of the grim news. */ vp->v_op = dead_vnodeop_p; vn_pollgone(vp); vp->v_tag = VT_NON; vp->v_flag &= ~VXLOCK; vp->v_vxthread = NULL; if (vp->v_flag & VXWANT) { vp->v_flag &= ~VXWANT; wakeup((caddr_t) vp); } lwkt_reltoken(vlock); } /* * Eliminate all activity associated with the requested vnode * and with all vnodes aliased to the requested vnode. */ int vop_revoke(ap) struct vop_revoke_args /* { struct vnode *a_vp; int a_flags; } */ *ap; { struct vnode *vp, *vq; lwkt_tokref ilock; dev_t dev; KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); vp = ap->a_vp; /* * If a vgone (or vclean) is already in progress, * wait until it is done and return. */ if (vp->v_flag & VXLOCK) { vp->v_flag |= VXWANT; /*lwkt_reltoken(vlock); ZZZ */ tsleep((caddr_t)vp, 0, "vop_revokeall", 0); return (0); } dev = vp->v_rdev; for (;;) { lwkt_gettoken(&ilock, &spechash_token); vq = SLIST_FIRST(&dev->si_hlist); lwkt_reltoken(&ilock); if (!vq) break; vgone(vq); } return (0); } /* * Recycle an unused vnode to the front of the free list. * Release the passed interlock if the vnode will be recycled. */ int vrecycle(struct vnode *vp, lwkt_tokref_t inter_lkp, struct thread *td) { lwkt_tokref vlock; lwkt_gettoken(&vlock, vp->v_interlock); if (vp->v_usecount == 0) { if (inter_lkp) lwkt_reltoken(inter_lkp); vgonel(vp, &vlock, td); return (1); } lwkt_reltoken(&vlock); return (0); } /* * Eliminate all activity associated with a vnode * in preparation for reuse. */ void vgone(struct vnode *vp) { struct thread *td = curthread; /* XXX */ lwkt_tokref vlock; lwkt_gettoken(&vlock, vp->v_interlock); vgonel(vp, &vlock, td); } /* * vgone, with the vp interlock held. */ void vgonel(struct vnode *vp, lwkt_tokref_t vlock, struct thread *td) { lwkt_tokref ilock; int s; /* * If a vgone (or vclean) is already in progress, * wait until it is done and return. */ if (vp->v_flag & VXLOCK) { vp->v_flag |= VXWANT; lwkt_reltoken(vlock); tsleep((caddr_t)vp, 0, "vgone", 0); return; } /* * Clean out the filesystem specific data. */ vclean(vp, vlock, DOCLOSE, td); lwkt_gettokref(vlock); /* * Delete from old mount point vnode list, if on one. */ if (vp->v_mount != NULL) insmntque(vp, (struct mount *)0); /* * If special device, remove it from special device alias list * if it is on one. */ if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_rdev != NULL) { lwkt_gettoken(&ilock, &spechash_token); SLIST_REMOVE(&vp->v_hashchain, vp, vnode, v_specnext); freedev(vp->v_rdev); lwkt_reltoken(&ilock); vp->v_rdev = NULL; } /* * If it is on the freelist and not already at the head, * move it to the head of the list. The test of the * VDOOMED flag and the reference count of zero is because * it will be removed from the free list by getnewvnode, * but will not have its reference count incremented until * after calling vgone. If the reference count were * incremented first, vgone would (incorrectly) try to * close the previous instance of the underlying object. */ if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) { s = splbio(); lwkt_gettoken(&ilock, &vnode_free_list_token); if (vp->v_flag & VFREE) TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); else freevnodes++; vp->v_flag |= VFREE; TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); lwkt_reltoken(&ilock); splx(s); } vp->v_type = VBAD; lwkt_reltoken(vlock); } /* * Lookup a vnode by device number. */ int vfinddev(dev, type, vpp) dev_t dev; enum vtype type; struct vnode **vpp; { lwkt_tokref ilock; struct vnode *vp; lwkt_gettoken(&ilock, &spechash_token); SLIST_FOREACH(vp, &dev->si_hlist, v_specnext) { if (type == vp->v_type) { *vpp = vp; lwkt_reltoken(&ilock); return (1); } } lwkt_reltoken(&ilock); return (0); } /* * Calculate the total number of references to a special device. */ int vcount(vp) struct vnode *vp; { lwkt_tokref ilock; struct vnode *vq; int count; count = 0; lwkt_gettoken(&ilock, &spechash_token); SLIST_FOREACH(vq, &vp->v_hashchain, v_specnext) count += vq->v_usecount; lwkt_reltoken(&ilock); return (count); } /* * Same as above, but using the dev_t as argument */ int count_dev(dev) dev_t dev; { struct vnode *vp; vp = SLIST_FIRST(&dev->si_hlist); if (vp == NULL) return (0); return(vcount(vp)); } /* * Print out a description of a vnode. */ static char *typename[] = {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; void vprint(label, vp) char *label; struct vnode *vp; { char buf[96]; if (label != NULL) printf("%s: %p: ", label, (void *)vp); else printf("%p: ", (void *)vp); printf("type %s, usecount %d, writecount %d, refcount %d,", typename[vp->v_type], vp->v_usecount, vp->v_writecount, vp->v_holdcnt); buf[0] = '\0'; if (vp->v_flag & VROOT) strcat(buf, "|VROOT"); if (vp->v_flag & VTEXT) strcat(buf, "|VTEXT"); if (vp->v_flag & VSYSTEM) strcat(buf, "|VSYSTEM"); if (vp->v_flag & VXLOCK) strcat(buf, "|VXLOCK"); if (vp->v_flag & VXWANT) strcat(buf, "|VXWANT"); if (vp->v_flag & VBWAIT) strcat(buf, "|VBWAIT"); if (vp->v_flag & VDOOMED) strcat(buf, "|VDOOMED"); if (vp->v_flag & VFREE) strcat(buf, "|VFREE"); if (vp->v_flag & VOBJBUF) strcat(buf, "|VOBJBUF"); if (buf[0] != '\0') printf(" flags (%s)", &buf[1]); if (vp->v_data == NULL) { printf("\n"); } else { printf("\n\t"); VOP_PRINT(vp); } } #ifdef DDB #include /* * List all of the locked vnodes in the system. * Called when debugging the kernel. */ DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) { struct thread *td = curthread; /* XXX */ lwkt_tokref ilock; struct mount *mp, *nmp; struct vnode *vp; printf("Locked vnodes\n"); lwkt_gettoken(&ilock, &mountlist_token); for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { if (vfs_busy(mp, LK_NOWAIT, &ilock, td)) { nmp = TAILQ_NEXT(mp, mnt_list); continue; } TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { if (VOP_ISLOCKED(vp, NULL)) vprint((char *)0, vp); } lwkt_gettokref(&ilock); nmp = TAILQ_NEXT(mp, mnt_list); vfs_unbusy(mp, td); } lwkt_reltoken(&ilock); } #endif /* * Top level filesystem related information gathering. */ static int sysctl_ovfs_conf (SYSCTL_HANDLER_ARGS); static int vfs_sysctl(SYSCTL_HANDLER_ARGS) { int *name = (int *)arg1 - 1; /* XXX */ u_int namelen = arg2 + 1; /* XXX */ struct vfsconf *vfsp; #if 1 || defined(COMPAT_PRELITE2) /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ if (namelen == 1) return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); #endif #ifdef notyet /* all sysctl names at this level are at least name and field */ if (namelen < 2) return (ENOTDIR); /* overloaded */ if (name[0] != VFS_GENERIC) { for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) if (vfsp->vfc_typenum == name[0]) break; if (vfsp == NULL) return (EOPNOTSUPP); return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, oldp, oldlenp, newp, newlen, p)); } #endif switch (name[1]) { case VFS_MAXTYPENUM: if (namelen != 2) return (ENOTDIR); return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); case VFS_CONF: if (namelen != 3) return (ENOTDIR); /* overloaded */ for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) if (vfsp->vfc_typenum == name[2]) break; if (vfsp == NULL) return (EOPNOTSUPP); return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); } return (EOPNOTSUPP); } SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, "Generic filesystem"); #if 1 || defined(COMPAT_PRELITE2) static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) { int error; struct vfsconf *vfsp; struct ovfsconf ovfs; for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ strcpy(ovfs.vfc_name, vfsp->vfc_name); ovfs.vfc_index = vfsp->vfc_typenum; ovfs.vfc_refcount = vfsp->vfc_refcount; ovfs.vfc_flags = vfsp->vfc_flags; error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); if (error) return error; } return 0; } #endif /* 1 || COMPAT_PRELITE2 */ #if 0 #define KINFO_VNODESLOP 10 /* * Dump vnode list (via sysctl). * Copyout address of vnode followed by vnode. */ /* ARGSUSED */ static int sysctl_vnode(SYSCTL_HANDLER_ARGS) { struct proc *p = curproc; /* XXX */ struct mount *mp, *nmp; struct vnode *nvp, *vp; lwkt_tokref ilock; lwkt_tokref jlock; int error; #define VPTRSZ sizeof (struct vnode *) #define VNODESZ sizeof (struct vnode) req->lock = 0; if (!req->oldptr) /* Make an estimate */ return (SYSCTL_OUT(req, 0, (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); lwkt_gettoken(&ilock, &mountlist_token); for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { if (vfs_busy(mp, LK_NOWAIT, &ilock, p)) { nmp = TAILQ_NEXT(mp, mnt_list); continue; } lwkt_gettoken(&jlock, &mntvnode_token); again: for (vp = TAILQ_FIRST(&mp->mnt_nvnodelist); vp != NULL; vp = nvp) { /* * Check that the vp is still associated with * this filesystem. RACE: could have been * recycled onto the same filesystem. */ if (vp->v_mount != mp) goto again; nvp = TAILQ_NEXT(vp, v_nmntvnodes); if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || (error = SYSCTL_OUT(req, vp, VNODESZ))) { lwkt_reltoken(&jlock); return (error); } } lwkt_reltoken(&jlock); lwkt_gettokref(&ilock); nmp = TAILQ_NEXT(mp, mnt_list); /* ZZZ */ vfs_unbusy(mp, p); } lwkt_reltoken(&ilock); return (0); } #endif /* * XXX * Exporting the vnode list on large systems causes them to crash. * Exporting the vnode list on medium systems causes sysctl to coredump. */ #if 0 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 0, 0, sysctl_vnode, "S,vnode", ""); #endif /* * Check to see if a filesystem is mounted on a block device. */ int vfs_mountedon(vp) struct vnode *vp; { if (vp->v_specmountpoint != NULL) return (EBUSY); return (0); } /* * Unmount all filesystems. The list is traversed in reverse order * of mounting to avoid dependencies. */ void vfs_unmountall() { struct mount *mp; struct thread *td = curthread; int error; if (td->td_proc == NULL) td = initproc->p_thread; /* XXX XXX use proc0 instead? */ /* * Since this only runs when rebooting, it is not interlocked. */ while(!TAILQ_EMPTY(&mountlist)) { mp = TAILQ_LAST(&mountlist, mntlist); error = dounmount(mp, MNT_FORCE, td); if (error) { TAILQ_REMOVE(&mountlist, mp, mnt_list); printf("unmount of %s failed (", mp->mnt_stat.f_mntonname); if (error == EBUSY) printf("BUSY)\n"); else printf("%d)\n", error); } else { /* The unmount has removed mp from the mountlist */ } } } /* * Build hash lists of net addresses and hang them off the mount point. * Called by ufs_mount() to set up the lists of export addresses. */ static int vfs_hang_addrlist(mp, nep, argp) struct mount *mp; struct netexport *nep; struct export_args *argp; { struct netcred *np; struct radix_node_head *rnh; int i; struct radix_node *rn; struct sockaddr *saddr, *smask = 0; struct domain *dom; int error; if (argp->ex_addrlen == 0) { if (mp->mnt_flag & MNT_DEFEXPORTED) return (EPERM); np = &nep->ne_defexported; np->netc_exflags = argp->ex_flags; np->netc_anon = argp->ex_anon; np->netc_anon.cr_ref = 1; mp->mnt_flag |= MNT_DEFEXPORTED; return (0); } if (argp->ex_addrlen < 0 || argp->ex_addrlen > MLEN) return (EINVAL); if (argp->ex_masklen < 0 || argp->ex_masklen > MLEN) return (EINVAL); i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK); bzero((caddr_t) np, i); saddr = (struct sockaddr *) (np + 1); if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen))) goto out; if (saddr->sa_len > argp->ex_addrlen) saddr->sa_len = argp->ex_addrlen; if (argp->ex_masklen) { smask = (struct sockaddr *) ((caddr_t) saddr + argp->ex_addrlen); error = copyin(argp->ex_mask, (caddr_t) smask, argp->ex_masklen); if (error) goto out; if (smask->sa_len > argp->ex_masklen) smask->sa_len = argp->ex_masklen; } i = saddr->sa_family; if ((rnh = nep->ne_rtable[i]) == 0) { /* * Seems silly to initialize every AF when most are not used, * do so on demand here */ for (dom = domains; dom; dom = dom->dom_next) if (dom->dom_family == i && dom->dom_rtattach) { dom->dom_rtattach((void **) &nep->ne_rtable[i], dom->dom_rtoffset); break; } if ((rnh = nep->ne_rtable[i]) == 0) { error = ENOBUFS; goto out; } } rn = (*rnh->rnh_addaddr) ((caddr_t) saddr, (caddr_t) smask, rnh, np->netc_rnodes); if (rn == 0 || np != (struct netcred *) rn) { /* already exists */ error = EPERM; goto out; } np->netc_exflags = argp->ex_flags; np->netc_anon = argp->ex_anon; np->netc_anon.cr_ref = 1; return (0); out: free(np, M_NETADDR); return (error); } /* ARGSUSED */ static int vfs_free_netcred(rn, w) struct radix_node *rn; void *w; { struct radix_node_head *rnh = (struct radix_node_head *) w; (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); free((caddr_t) rn, M_NETADDR); return (0); } /* * Free the net address hash lists that are hanging off the mount points. */ static void vfs_free_addrlist(nep) struct netexport *nep; { int i; struct radix_node_head *rnh; for (i = 0; i <= AF_MAX; i++) if ((rnh = nep->ne_rtable[i])) { (*rnh->rnh_walktree) (rnh, vfs_free_netcred, (caddr_t) rnh); free((caddr_t) rnh, M_RTABLE); nep->ne_rtable[i] = 0; } } int vfs_export(mp, nep, argp) struct mount *mp; struct netexport *nep; struct export_args *argp; { int error; if (argp->ex_flags & MNT_DELEXPORT) { if (mp->mnt_flag & MNT_EXPUBLIC) { vfs_setpublicfs(NULL, NULL, NULL); mp->mnt_flag &= ~MNT_EXPUBLIC; } vfs_free_addrlist(nep); mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); } if (argp->ex_flags & MNT_EXPORTED) { if (argp->ex_flags & MNT_EXPUBLIC) { if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) return (error); mp->mnt_flag |= MNT_EXPUBLIC; } if ((error = vfs_hang_addrlist(mp, nep, argp))) return (error); mp->mnt_flag |= MNT_EXPORTED; } return (0); } /* * Set the publicly exported filesystem (WebNFS). Currently, only * one public filesystem is possible in the spec (RFC 2054 and 2055) */ int vfs_setpublicfs(mp, nep, argp) struct mount *mp; struct netexport *nep; struct export_args *argp; { int error; struct vnode *rvp; char *cp; /* * mp == NULL -> invalidate the current info, the FS is * no longer exported. May be called from either vfs_export * or unmount, so check if it hasn't already been done. */ if (mp == NULL) { if (nfs_pub.np_valid) { nfs_pub.np_valid = 0; if (nfs_pub.np_index != NULL) { FREE(nfs_pub.np_index, M_TEMP); nfs_pub.np_index = NULL; } } return (0); } /* * Only one allowed at a time. */ if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) return (EBUSY); /* * Get real filehandle for root of exported FS. */ bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; if ((error = VFS_ROOT(mp, &rvp))) return (error); if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) return (error); vput(rvp); /* * If an indexfile was specified, pull it in. */ if (argp->ex_indexfile != NULL) { MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, M_WAITOK); error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, MAXNAMLEN, (size_t *)0); if (!error) { /* * Check for illegal filenames. */ for (cp = nfs_pub.np_index; *cp; cp++) { if (*cp == '/') { error = EINVAL; break; } } } if (error) { FREE(nfs_pub.np_index, M_TEMP); return (error); } } nfs_pub.np_mount = mp; nfs_pub.np_valid = 1; return (0); } struct netcred * vfs_export_lookup(mp, nep, nam) struct mount *mp; struct netexport *nep; struct sockaddr *nam; { struct netcred *np; struct radix_node_head *rnh; struct sockaddr *saddr; np = NULL; if (mp->mnt_flag & MNT_EXPORTED) { /* * Lookup in the export list first. */ if (nam != NULL) { saddr = nam; rnh = nep->ne_rtable[saddr->sa_family]; if (rnh != NULL) { np = (struct netcred *) (*rnh->rnh_matchaddr)((caddr_t)saddr, rnh); if (np && np->netc_rnodes->rn_flags & RNF_ROOT) np = NULL; } } /* * If no address match, use the default if it exists. */ if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) np = &nep->ne_defexported; } return (np); } /* * perform msync on all vnodes under a mount point. The mount point must * be locked. This code is also responsible for lazy-freeing unreferenced * vnodes whos VM objects no longer contain pages. * * NOTE: MNT_WAIT still skips vnodes in the VXLOCK state. */ static int vfs_msync_scan1(struct mount *mp, struct vnode *vp, void *data); static int vfs_msync_scan2(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data); void vfs_msync(struct mount *mp, int flags) { vmntvnodescan(mp, vfs_msync_scan1, vfs_msync_scan2, (void *)flags); } /* * scan1 is a fast pre-check. There could be hundreds of thousands of * vnodes, we cannot afford to do anything heavy weight until we have a * fairly good indication that there is work to do. */ static int vfs_msync_scan1(struct mount *mp, struct vnode *vp, void *data) { int flags = (int)data; if ((vp->v_flag & VXLOCK) == 0) { if (VSHOULDFREE(vp)) return(0); if ((mp->mnt_flag & MNT_RDONLY) == 0 && (vp->v_flag & VOBJDIRTY) && (flags == MNT_WAIT || VOP_ISLOCKED(vp, NULL) == 0)) { return(0); } } return(-1); } static int vfs_msync_scan2(struct mount *mp, struct vnode *vp, lwkt_tokref_t vlock, void *data) { vm_object_t obj; int error; int flags = (int)data; if (vp->v_flag & VXLOCK) return(0); if ((mp->mnt_flag & MNT_RDONLY) == 0 && (vp->v_flag & VOBJDIRTY) && (flags == MNT_WAIT || VOP_ISLOCKED(vp, NULL) == 0)) { error = vget(vp, vlock, LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ | LK_INTERLOCK, curthread); if (error == 0) { if (VOP_GETVOBJECT(vp, &obj) == 0) { vm_object_page_clean(obj, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : OBJPC_NOSYNC); } vput(vp); } return(0); } vmaybefree(vp); lwkt_reltoken(vlock); return(0); } /* * Create the VM object needed for VMIO and mmap support. This * is done for all VREG files in the system. Some filesystems might * afford the additional metadata buffering capability of the * VMIO code by making the device node be VMIO mode also. * * vp must be locked when vfs_object_create is called. */ int vfs_object_create(struct vnode *vp, struct thread *td) { return (VOP_CREATEVOBJECT(vp, td)); } /* * NOTE: the vnode interlock must be held during the call. We have to recheck * the VFREE flag since the vnode may have been removed from the free list * while we were blocked on vnode_free_list_token. The use or hold count * must have already been bumped by the caller. */ static void vbusy(struct vnode *vp) { lwkt_tokref ilock; lwkt_gettoken(&ilock, &vnode_free_list_token); if ((vp->v_flag & VFREE) != 0) { TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); freevnodes--; vp->v_flag &= ~(VFREE|VAGE); } lwkt_reltoken(&ilock); } /* * NOTE: the vnode interlock must be held during the call. The use or hold * count must have already been bumped by the caller. We use a VINFREE to * interlock against other calls to vfree() which might occur while we * are blocked. The vnode cannot be reused until it has actually been * placed on the free list, so there are no other races even though the * use and hold counts are 0. */ static void vfree(struct vnode *vp) { lwkt_tokref ilock; if ((vp->v_flag & VINFREE) == 0) { vp->v_flag |= VINFREE; lwkt_gettoken(&ilock, &vnode_free_list_token); /* can block */ KASSERT((vp->v_flag & VFREE) == 0, ("vnode already free")); if (vp->v_flag & VAGE) { TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); } else { TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); } freevnodes++; vp->v_flag &= ~(VAGE|VINFREE); vp->v_flag |= VFREE; lwkt_reltoken(&ilock); /* can block */ } } /* * Record a process's interest in events which might happen to * a vnode. Because poll uses the historic select-style interface * internally, this routine serves as both the ``check for any * pending events'' and the ``record my interest in future events'' * functions. (These are done together, while the lock is held, * to avoid race conditions.) */ int vn_pollrecord(struct vnode *vp, struct thread *td, int events) { lwkt_tokref ilock; lwkt_gettoken(&ilock, &vp->v_pollinfo.vpi_token); if (vp->v_pollinfo.vpi_revents & events) { /* * This leaves events we are not interested * in available for the other process which * which presumably had requested them * (otherwise they would never have been * recorded). */ events &= vp->v_pollinfo.vpi_revents; vp->v_pollinfo.vpi_revents &= ~events; lwkt_reltoken(&ilock); return events; } vp->v_pollinfo.vpi_events |= events; selrecord(td, &vp->v_pollinfo.vpi_selinfo); lwkt_reltoken(&ilock); return 0; } /* * Note the occurrence of an event. If the VN_POLLEVENT macro is used, * it is possible for us to miss an event due to race conditions, but * that condition is expected to be rare, so for the moment it is the * preferred interface. */ void vn_pollevent(vp, events) struct vnode *vp; short events; { lwkt_tokref ilock; lwkt_gettoken(&ilock, &vp->v_pollinfo.vpi_token); if (vp->v_pollinfo.vpi_events & events) { /* * We clear vpi_events so that we don't * call selwakeup() twice if two events are * posted before the polling process(es) is * awakened. This also ensures that we take at * most one selwakeup() if the polling process * is no longer interested. However, it does * mean that only one event can be noticed at * a time. (Perhaps we should only clear those * event bits which we note?) XXX */ vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */ vp->v_pollinfo.vpi_revents |= events; selwakeup(&vp->v_pollinfo.vpi_selinfo); } lwkt_reltoken(&ilock); } /* * Wake up anyone polling on vp because it is being revoked. * This depends on dead_poll() returning POLLHUP for correct * behavior. */ void vn_pollgone(vp) struct vnode *vp; { lwkt_tokref ilock; lwkt_gettoken(&ilock, &vp->v_pollinfo.vpi_token); if (vp->v_pollinfo.vpi_events) { vp->v_pollinfo.vpi_events = 0; selwakeup(&vp->v_pollinfo.vpi_selinfo); } lwkt_reltoken(&ilock); } /* * Routine to create and manage a filesystem syncer vnode. */ #define sync_close ((int (*) (struct vop_close_args *))nullop) static int sync_fsync (struct vop_fsync_args *); static int sync_inactive (struct vop_inactive_args *); static int sync_reclaim (struct vop_reclaim_args *); #define sync_lock ((int (*) (struct vop_lock_args *))vop_nolock) #define sync_unlock ((int (*) (struct vop_unlock_args *))vop_nounlock) static int sync_print (struct vop_print_args *); #define sync_islocked ((int(*) (struct vop_islocked_args *))vop_noislocked) static vop_t **sync_vnodeop_p; static struct vnodeopv_entry_desc sync_vnodeop_entries[] = { { &vop_default_desc, (vop_t *) vop_eopnotsupp }, { &vop_close_desc, (vop_t *) sync_close }, /* close */ { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */ { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */ { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */ { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */ { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */ { &vop_print_desc, (vop_t *) sync_print }, /* print */ { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */ { NULL, NULL } }; static struct vnodeopv_desc sync_vnodeop_opv_desc = { &sync_vnodeop_p, sync_vnodeop_entries }; VNODEOP_SET(sync_vnodeop_opv_desc); /* * Create a new filesystem syncer vnode for the specified mount point. * This vnode is placed on the worklist and is responsible for sync'ing * the filesystem. * * NOTE: read-only mounts are also placed on the worklist. The filesystem * sync code is also responsible for cleaning up vnodes. */ int vfs_allocate_syncvnode(struct mount *mp) { struct vnode *vp; static long start, incr, next; int error; /* Allocate a new vnode */ if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) { mp->mnt_syncer = NULL; return (error); } vp->v_type = VNON; /* * Place the vnode onto the syncer worklist. We attempt to * scatter them about on the list so that they will go off * at evenly distributed times even if all the filesystems * are mounted at once. */ next += incr; if (next == 0 || next > syncer_maxdelay) { start /= 2; incr /= 2; if (start == 0) { start = syncer_maxdelay / 2; incr = syncer_maxdelay; } next = start; } vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0); mp->mnt_syncer = vp; return (0); } /* * Do a lazy sync of the filesystem. */ static int sync_fsync(ap) struct vop_fsync_args /* { struct vnode *a_vp; struct ucred *a_cred; int a_waitfor; struct thread *a_td; } */ *ap; { struct vnode *syncvp = ap->a_vp; struct mount *mp = syncvp->v_mount; struct thread *td = ap->a_td; lwkt_tokref ilock; int asyncflag; /* * We only need to do something if this is a lazy evaluation. */ if (ap->a_waitfor != MNT_LAZY) return (0); /* * Move ourselves to the back of the sync list. */ vn_syncer_add_to_worklist(syncvp, syncdelay); /* * Walk the list of vnodes pushing all that are dirty and * not already on the sync list, and freeing vnodes which have * no refs and whos VM objects are empty. vfs_msync() handles * the VM issues and must be called whether the mount is readonly * or not. */ lwkt_gettoken(&ilock, &mountlist_token); if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &ilock, td) != 0) { lwkt_reltoken(&ilock); return (0); } if (mp->mnt_flag & MNT_RDONLY) { vfs_msync(mp, MNT_NOWAIT); } else { asyncflag = mp->mnt_flag & MNT_ASYNC; mp->mnt_flag &= ~MNT_ASYNC; /* ZZZ hack */ vfs_msync(mp, MNT_NOWAIT); VFS_SYNC(mp, MNT_LAZY, td); if (asyncflag) mp->mnt_flag |= MNT_ASYNC; } vfs_unbusy(mp, td); return (0); } /* * The syncer vnode is no referenced. */ static int sync_inactive(ap) struct vop_inactive_args /* { struct vnode *a_vp; struct proc *a_p; } */ *ap; { vgone(ap->a_vp); return (0); } /* * The syncer vnode is no longer needed and is being decommissioned. * * Modifications to the worklist must be protected at splbio(). */ static int sync_reclaim(ap) struct vop_reclaim_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; int s; s = splbio(); vp->v_mount->mnt_syncer = NULL; if (vp->v_flag & VONWORKLST) { LIST_REMOVE(vp, v_synclist); vp->v_flag &= ~VONWORKLST; } splx(s); return (0); } /* * Print out a syncer vnode. */ static int sync_print(ap) struct vop_print_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; printf("syncer vnode"); if (vp->v_vnlock != NULL) lockmgr_printinfo(vp->v_vnlock); printf("\n"); return (0); } /* * extract the dev_t from a VBLK or VCHR */ dev_t vn_todev(vp) struct vnode *vp; { if (vp->v_type != VBLK && vp->v_type != VCHR) return (NODEV); return (vp->v_rdev); } /* * Check if vnode represents a disk device */ int vn_isdisk(vp, errp) struct vnode *vp; int *errp; { if (vp->v_type != VBLK && vp->v_type != VCHR) { if (errp != NULL) *errp = ENOTBLK; return (0); } if (vp->v_rdev == NULL) { if (errp != NULL) *errp = ENXIO; return (0); } if (!dev_dport(vp->v_rdev)) { if (errp != NULL) *errp = ENXIO; return (0); } if (!(dev_dflags(vp->v_rdev) & D_DISK)) { if (errp != NULL) *errp = ENOTBLK; return (0); } if (errp != NULL) *errp = 0; return (1); } void NDFREE(ndp, flags) struct nameidata *ndp; const uint flags; { if (!(flags & NDF_NO_FREE_PNBUF) && (ndp->ni_cnd.cn_flags & CNP_HASBUF)) { zfree(namei_zone, ndp->ni_cnd.cn_pnbuf); ndp->ni_cnd.cn_flags &= ~CNP_HASBUF; } if (!(flags & NDF_NO_DNCP_RELE) && (ndp->ni_cnd.cn_flags & CNP_WANTDNCP) && ndp->ni_dncp) { cache_drop(ndp->ni_dncp); ndp->ni_dncp = NULL; } if (!(flags & NDF_NO_NCP_RELE) && (ndp->ni_cnd.cn_flags & CNP_WANTNCP) && ndp->ni_ncp) { cache_drop(ndp->ni_ncp); ndp->ni_ncp = NULL; } if (!(flags & NDF_NO_DVP_UNLOCK) && (ndp->ni_cnd.cn_flags & CNP_LOCKPARENT) && ndp->ni_dvp != ndp->ni_vp) { VOP_UNLOCK(ndp->ni_dvp, NULL, 0, ndp->ni_cnd.cn_td); } if (!(flags & NDF_NO_DVP_RELE) && (ndp->ni_cnd.cn_flags & (CNP_LOCKPARENT|CNP_WANTPARENT))) { vrele(ndp->ni_dvp); ndp->ni_dvp = NULL; } if (!(flags & NDF_NO_VP_UNLOCK) && (ndp->ni_cnd.cn_flags & CNP_LOCKLEAF) && ndp->ni_vp) { VOP_UNLOCK(ndp->ni_vp, NULL, 0, ndp->ni_cnd.cn_td); } if (!(flags & NDF_NO_VP_RELE) && ndp->ni_vp) { vrele(ndp->ni_vp); ndp->ni_vp = NULL; } if (!(flags & NDF_NO_STARTDIR_RELE) && (ndp->ni_cnd.cn_flags & CNP_SAVESTART)) { vrele(ndp->ni_startdir); ndp->ni_startdir = NULL; } } #ifdef DEBUG_VFS_LOCKS void assert_vop_locked(struct vnode *vp, const char *str) { if (vp && IS_LOCKING_VFS(vp) && !VOP_ISLOCKED(vp, NULL)) { panic("%s: %p is not locked shared but should be", str, vp); } } void assert_vop_unlocked(struct vnode *vp, const char *str) { if (vp && IS_LOCKING_VFS(vp)) { if (VOP_ISLOCKED(vp, curthread) == LK_EXCLUSIVE) { panic("%s: %p is locked but should not be", str, vp); } } } #endif