diff options
Diffstat (limited to 'sys/kern/vfs_subr.c')
| -rw-r--r-- | sys/kern/vfs_subr.c | 2872 |
1 files changed, 2872 insertions, 0 deletions
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c new file mode 100644 index 0000000..44b1698 --- /dev/null +++ b/sys/kern/vfs_subr.c @@ -0,0 +1,2872 @@ +/* + * 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 + * $Id: vfs_subr.c,v 1.182 1999/01/10 01:58:26 eivind Exp $ + */ + +/* + * External virtual filesystem routines + */ +#include "opt_ddb.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/conf.h> +#include <sys/fcntl.h> +#include <sys/kernel.h> +#include <sys/proc.h> +#include <sys/malloc.h> +#include <sys/mount.h> +#include <sys/socket.h> +#include <sys/vnode.h> +#include <sys/stat.h> +#include <sys/buf.h> +#include <sys/domain.h> +#include <sys/dirent.h> +#include <sys/vmmeter.h> + +#include <machine/limits.h> + +#include <vm/vm.h> +#include <vm/vm_param.h> +#include <vm/vm_prot.h> +#include <vm/vm_object.h> +#include <vm/vm_extern.h> +#include <vm/pmap.h> +#include <vm/vm_map.h> +#include <vm/vm_page.h> +#include <vm/vm_pager.h> +#include <vm/vnode_pager.h> +#include <vm/vm_zone.h> +#include <sys/sysctl.h> + +#include <miscfs/specfs/specdev.h> + +static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); + +static void insmntque __P((struct vnode *vp, struct mount *mp)); +static void vclean __P((struct vnode *vp, int flags, struct proc *p)); +static void vfree __P((struct vnode *)); +static void vgonel __P((struct vnode *vp, struct proc *p)); +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 */ +struct tobefreelist vnode_tobefree_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, ""); + +int vfs_ioopt = 0; +#ifdef ENABLE_VFS_IOOPT +SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); +#endif + +struct mntlist mountlist; /* mounted filesystem list */ +struct simplelock mountlist_slock; +struct simplelock mntvnode_slock; +int nfs_mount_type = -1; +#ifndef NULL_SIMPLELOCKS +static struct simplelock mntid_slock; +static struct simplelock vnode_free_list_slock; +static struct simplelock spechash_slock; +#endif +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; +int rushjob; /* number of slots to run ASAP */ + +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, ""); + +static void vfs_free_addrlist __P((struct netexport *nep)); +static int vfs_free_netcred __P((struct radix_node *rn, void *w)); +static int vfs_hang_addrlist __P((struct mount *mp, struct netexport *nep, + struct export_args *argp)); + +/* + * Initialize the vnode management data structures. + */ +void +vntblinit() +{ + + desiredvnodes = maxproc + cnt.v_page_count / 4; + simple_lock_init(&mntvnode_slock); + simple_lock_init(&mntid_slock); + simple_lock_init(&spechash_slock); + TAILQ_INIT(&vnode_free_list); + TAILQ_INIT(&vnode_tobefree_list); + simple_lock_init(&vnode_free_list_slock); + CIRCLEQ_INIT(&mountlist); + 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(mp, flags, interlkp, p) + struct mount *mp; + int flags; + struct simplelock *interlkp; + struct proc *p; +{ + int lkflags; + + if (mp->mnt_kern_flag & MNTK_UNMOUNT) { + if (flags & LK_NOWAIT) + return (ENOENT); + mp->mnt_kern_flag |= MNTK_MWAIT; + if (interlkp) { + simple_unlock(interlkp); + } + /* + * 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. + */ + tsleep((caddr_t)mp, PVFS, "vfs_busy", 0); + if (interlkp) { + simple_lock(interlkp); + } + return (ENOENT); + } + lkflags = LK_SHARED | LK_NOPAUSE; + if (interlkp) + lkflags |= LK_INTERLOCK; + if (lockmgr(&mp->mnt_lock, lkflags, interlkp, p)) + panic("vfs_busy: unexpected lock failure"); + return (0); +} + +/* + * Free a busy filesystem. + */ +void +vfs_unbusy(mp, p) + struct mount *mp; + struct proc *p; +{ + + lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, p); +} + +/* + * 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(fstypename, devname, mpp) + char *fstypename; + char *devname; + struct mount **mpp; +{ + struct proc *p = curproc; /* 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, PVFS, "vfslock", 0, LK_NOPAUSE); + (void)vfs_busy(mp, LK_NOWAIT, 0, p); + LIST_INIT(&mp->mnt_vnodelist); + mp->mnt_vfc = vfsp; + mp->mnt_op = vfsp->vfc_vfsops; + mp->mnt_flag = MNT_RDONLY; + mp->mnt_vnodecovered = NULLVP; + vfsp->vfc_refcount++; + 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) __P((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; +{ + register struct mount *mp; + + simple_lock(&mountlist_slock); + for (mp = mountlist.cqh_first; mp != (void *)&mountlist; + mp = mp->mnt_list.cqe_next) { + if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && + mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { + simple_unlock(&mountlist_slock); + return (mp); + } + } + simple_unlock(&mountlist_slock); + return ((struct mount *) 0); +} + +/* + * Get a new unique fsid + */ +void +vfs_getnewfsid(mp) + struct mount *mp; +{ + static u_short xxxfs_mntid; + + fsid_t tfsid; + int mtype; + + simple_lock(&mntid_slock); + mtype = mp->mnt_vfc->vfc_typenum; + mp->mnt_stat.f_fsid.val[0] = makedev(nblkdev + mtype, 0); + mp->mnt_stat.f_fsid.val[1] = mtype; + if (xxxfs_mntid == 0) + ++xxxfs_mntid; + tfsid.val[0] = makedev(nblkdev + mtype, xxxfs_mntid); + tfsid.val[1] = mtype; + if (mountlist.cqh_first != (void *)&mountlist) { + while (vfs_getvfs(&tfsid)) { + tfsid.val[0]++; + xxxfs_mntid++; + } + } + mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; + simple_unlock(&mntid_slock); +} + +/* + * Set vnode attributes to VNOVAL + */ +void +vattr_null(vap) + register 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; +} + +/* + * 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 proc *p = curproc; /* XXX */ + struct vnode *vp, *tvp, *nvp; + vm_object_t object; + TAILQ_HEAD(freelst, vnode) vnode_tmp_list; + + /* + * We take the least recently used vnode from the freelist + * if we can get it and it has no cached pages, and no + * namecache entries are relative to it. + * Otherwise we allocate a new vnode + */ + + s = splbio(); + simple_lock(&vnode_free_list_slock); + TAILQ_INIT(&vnode_tmp_list); + + for (vp = TAILQ_FIRST(&vnode_tobefree_list); vp; vp = nvp) { + nvp = TAILQ_NEXT(vp, v_freelist); + TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); + if (vp->v_flag & VAGE) { + TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); + } else { + TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); + } + vp->v_flag &= ~(VTBFREE|VAGE); + vp->v_flag |= VFREE; + if (vp->v_usecount) + panic("tobe free vnode isn't"); + freevnodes++; + } + + if (wantfreevnodes && freevnodes < wantfreevnodes) { + vp = NULL; + } else if (!wantfreevnodes && freevnodes <= desiredvnodes) { + /* + * XXX: this is only here to be backwards compatible + */ + vp = NULL; + } else { + for (vp = TAILQ_FIRST(&vnode_free_list); vp; vp = nvp) { + nvp = TAILQ_NEXT(vp, v_freelist); + if (!simple_lock_try(&vp->v_interlock)) + continue; + if (vp->v_usecount) + panic("free vnode isn't"); + + object = vp->v_object; + if (object && (object->resident_page_count || object->ref_count)) { + printf("object inconsistant state: RPC: %d, RC: %d\n", + object->resident_page_count, object->ref_count); + /* Don't recycle if it's caching some pages */ + TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); + TAILQ_INSERT_TAIL(&vnode_tmp_list, vp, v_freelist); + continue; + } else if (LIST_FIRST(&vp->v_cache_src)) { + /* Don't recycle if active in the namecache */ + simple_unlock(&vp->v_interlock); + continue; + } else { + break; + } + } + } + + for (tvp = TAILQ_FIRST(&vnode_tmp_list); tvp; tvp = nvp) { + nvp = TAILQ_NEXT(tvp, v_freelist); + TAILQ_REMOVE(&vnode_tmp_list, tvp, v_freelist); + TAILQ_INSERT_TAIL(&vnode_free_list, tvp, v_freelist); + simple_unlock(&tvp->v_interlock); + } + + if (vp) { + vp->v_flag |= VDOOMED; + TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); + freevnodes--; + simple_unlock(&vnode_free_list_slock); + cache_purge(vp); + vp->v_lease = NULL; + if (vp->v_type != VBAD) { + vgonel(vp, p); + } else { + simple_unlock(&vp->v_interlock); + } + +#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_lastr = 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 */ + vp->v_maxio = 0; + } else { + simple_unlock(&vnode_free_list_slock); + vp = (struct vnode *) zalloc(vnode_zone); + bzero((char *) vp, sizeof *vp); + simple_lock_init(&vp->v_interlock); + vp->v_dd = vp; + cache_purge(vp); + LIST_INIT(&vp->v_cache_src); + TAILQ_INIT(&vp->v_cache_dst); + 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, p, p->p_ucred); + return (0); +} + +/* + * Move a vnode from one mount queue to another. + */ +static void +insmntque(vp, mp) + register struct vnode *vp; + register struct mount *mp; +{ + + simple_lock(&mntvnode_slock); + /* + * Delete from old mount point vnode list, if on one. + */ + if (vp->v_mount != NULL) + LIST_REMOVE(vp, v_mntvnodes); + /* + * Insert into list of vnodes for the new mount point, if available. + */ + if ((vp->v_mount = mp) == NULL) { + simple_unlock(&mntvnode_slock); + return; + } + LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); + simple_unlock(&mntvnode_slock); +} + +/* + * Update outstanding I/O count and do wakeup if requested. + */ +void +vwakeup(bp) + register struct buf *bp; +{ + register 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(vp, flags, cred, p, slpflag, slptimeo) + register struct vnode *vp; + int flags; + struct ucred *cred; + struct proc *p; + int slpflag, slptimeo; +{ + register struct buf *bp; + struct buf *nbp, *blist; + int s, error; + vm_object_t object; + + if (flags & V_SAVE) { + s = splbio(); + while (vp->v_numoutput) { + vp->v_flag |= VBWAIT; + error = tsleep((caddr_t)&vp->v_numoutput, + slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo); + if (error) { + splx(s); + return (error); + } + } + if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { + splx(s); + if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 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 (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + error = tsleep((caddr_t) bp, + slpflag | (PRIBIO + 4), "vinvalbuf", + slptimeo); + if (error) { + splx(s); + return (error); + } + break; + } + /* + * 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) { + vfs_bio_awrite(bp); + } else { + bremfree(bp); + bp->b_flags |= (B_BUSY | B_ASYNC); + VOP_BWRITE(bp); + } + } else { + bremfree(bp); + bp->b_flags |= B_BUSY; + (void) VOP_BWRITE(bp); + } + break; + } + bremfree(bp); + bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF | B_BUSY); + bp->b_flags &= ~B_ASYNC; + brelse(bp); + } + } + + while (vp->v_numoutput > 0) { + vp->v_flag |= VBWAIT; + tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); + } + + splx(s); + + /* + * Destroy the copy in the VM cache, too. + */ + simple_lock(&vp->v_interlock); + object = vp->v_object; + if (object != NULL) { + vm_object_page_remove(object, 0, 0, + (flags & V_SAVE) ? TRUE : FALSE); + } + simple_unlock(&vp->v_interlock); + + 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(vp, cred, p, length, blksize) + register struct vnode *vp; + struct ucred *cred; + struct proc *p; + off_t length; + int blksize; +{ + register 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 (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + tsleep(bp, PRIBIO + 4, "vtrb1", 0); + goto restart; + } else { + bremfree(bp); + bp->b_flags |= (B_BUSY | B_INVAL | B_RELBUF); + bp->b_flags &= ~B_ASYNC; + brelse(bp); + anyfreed = 1; + } + if (nbp && (((nbp->b_xflags & B_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 (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + tsleep(bp, PRIBIO + 4, "vtrb2", 0); + goto restart; + } else { + bremfree(bp); + bp->b_flags |= (B_BUSY | B_INVAL | B_RELBUF); + bp->b_flags &= ~B_ASYNC; + brelse(bp); + anyfreed = 1; + } + if (nbp && (((nbp->b_xflags & B_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 (bp->b_flags & B_BUSY) { + bp->b_flags |= B_WANTED; + tsleep(bp, PRIBIO, "vtrb3", 0); + } else { + bremfree(bp); + bp->b_flags |= B_BUSY; + if (bp->b_vp == vp) { + bp->b_flags |= B_ASYNC; + } else { + bp->b_flags &= ~B_ASYNC; + } + VOP_BWRITE(bp); + } + goto restartsync; + } + + } + } + + while (vp->v_numoutput > 0) { + vp->v_flag |= VBWAIT; + tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0); + } + + splx(s); + + vnode_pager_setsize(vp, length); + + return (0); +} + +/* + * Associate a buffer with a vnode. + */ +void +bgetvp(vp, bp) + register struct vnode *vp; + register struct buf *bp; +{ + int s; + + KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); + + vhold(vp); + bp->b_vp = vp; + if (vp->v_type == VBLK || vp->v_type == VCHR) + bp->b_dev = vp->v_rdev; + else + bp->b_dev = NODEV; + /* + * Insert onto list for new vnode. + */ + s = splbio(); + bp->b_xflags |= B_VNCLEAN; + bp->b_xflags &= ~B_VNDIRTY; + TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); + splx(s); +} + +/* + * Disassociate a buffer from a vnode. + */ +void +brelvp(bp) + register 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 & (B_VNDIRTY|B_VNCLEAN)) { + if (bp->b_xflags & B_VNDIRTY) + listheadp = &vp->v_dirtyblkhd; + else + listheadp = &vp->v_cleanblkhd; + TAILQ_REMOVE(listheadp, bp, b_vnbufs); + bp->b_xflags &= ~(B_VNDIRTY|B_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 syner 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. + */ +void +vn_syncer_add_to_worklist(vp, delay) + 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); +} + +static void sched_sync __P((void)); +static struct proc *updateproc; +static struct kproc_desc up_kp = { + "syncer", + sched_sync, + &updateproc +}; +SYSINIT_KT(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 proc *p = updateproc; + + for (;;) { + starttime = time_second; + + /* + * Push files whose dirty time has expired. + */ + 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) { + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p); + VOP_UNLOCK(vp, 0, p); + if (LIST_FIRST(slp) == vp) { + if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && + vp->v_type != VBLK) + panic("sched_sync: fsync failed"); + /* + * Move ourselves to the back of the sync list. + */ + LIST_REMOVE(vp, v_synclist); + vn_syncer_add_to_worklist(vp, syncdelay); + } + } + + /* + * 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, PPAUSE, "syncer", 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) + register struct vnode *vp; + register struct buf *bp; +{ + + KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); + + bp->b_vp = vp; + bp->b_flags |= B_PAGING; + if (vp->v_type == VBLK || vp->v_type == VCHR) + bp->b_dev = vp->v_rdev; + else + bp->b_dev = NODEV; +} + +/* + * Disassociate a p-buffer from a vnode. + */ +void +pbrelvp(bp) + register struct buf *bp; +{ + + KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); + +#if !defined(MAX_PERF) + /* XXX REMOVE ME */ + if (bp->b_vnbufs.tqe_next != NULL) { + panic( + "relpbuf(): b_vp was probably reassignbuf()d %p %x", + bp, + (int)bp->b_flags + ); + } +#endif + bp->b_vp = (struct vnode *) 0; + bp->b_flags &= ~B_PAGING; +} + +void +pbreassignbuf(bp, newvp) + struct buf *bp; + struct vnode *newvp; +{ +#if !defined(MAX_PERF) + if ((bp->b_flags & B_PAGING) == 0) { + panic( + "pbreassignbuf() on non phys bp %p", + bp + ); + } +#endif + 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) + register struct buf *bp; + register struct vnode *newvp; +{ + struct buflists *listheadp; + struct vnode *oldvp; + int delay; + int s; + + if (newvp == NULL) { + printf("reassignbuf: NULL"); + return; + } + +#if !defined(MAX_PERF) + /* + * 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"); +#endif + + s = splbio(); + /* + * Delete from old vnode list, if on one. + */ + if (bp->b_xflags & (B_VNDIRTY|B_VNCLEAN)) { + oldvp = bp->b_vp; + if (bp->b_xflags & B_VNDIRTY) + listheadp = &oldvp->v_dirtyblkhd; + else + listheadp = &oldvp->v_cleanblkhd; + TAILQ_REMOVE(listheadp, bp, b_vnbufs); + bp->b_xflags &= ~(B_VNDIRTY|B_VNCLEAN); + vdrop(oldvp); + } + /* + * 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 = syncdelay / 3; + break; + case VBLK: + if (newvp->v_specmountpoint != NULL) { + delay = syncdelay / 2; + break; + } + /* fall through */ + default: + delay = syncdelay; + } + vn_syncer_add_to_worklist(newvp, delay); + } + bp->b_xflags |= B_VNDIRTY; + tbp = TAILQ_FIRST(listheadp); + if (tbp == NULL || + (bp->b_lblkno >= 0 && tbp->b_lblkno > bp->b_lblkno)) { + TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); + } else { + if (bp->b_lblkno >= 0) { + struct buf *ttbp; + while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) && + (ttbp->b_lblkno < bp->b_lblkno)) { + tbp = ttbp; + } + TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); + } else { + TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); + } + } + } else { + bp->b_xflags |= B_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); + } + } + 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; +{ + register struct vnode *vp; + struct vnode *nvp; + int error; + + /* XXX 255 is for mfs. */ + if (dev == NODEV || (major(dev) != 255 && (major(dev) >= nblkdev || + bdevsw[major(dev)] == NULL))) { + *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; + if ((nvp = checkalias(vp, dev, (struct mount *)0)) != NULL) { + vput(vp); + vp = nvp; + } + *vpp = vp; + return (0); +} + +/* + * Check to see if the new vnode represents a special device + * for which we already have a vnode (either because of + * bdevvp() or because of a different vnode representing + * the same block device). If such an alias exists, deallocate + * the existing contents and return the aliased vnode. The + * caller is responsible for filling it with its new contents. + */ +struct vnode * +checkalias(nvp, nvp_rdev, mp) + register struct vnode *nvp; + dev_t nvp_rdev; + struct mount *mp; +{ + struct proc *p = curproc; /* XXX */ + struct vnode *vp; + struct vnode **vpp; + + if (nvp->v_type != VBLK && nvp->v_type != VCHR) + return (NULLVP); + + vpp = &speclisth[SPECHASH(nvp_rdev)]; +loop: + simple_lock(&spechash_slock); + for (vp = *vpp; vp; vp = vp->v_specnext) { + if (nvp_rdev != vp->v_rdev || nvp->v_type != vp->v_type) + continue; + /* + * Alias, but not in use, so flush it out. + * Only alias active device nodes. + * Not sure why we don't re-use this like we do below. + */ + simple_lock(&vp->v_interlock); + if (vp->v_usecount == 0) { + simple_unlock(&spechash_slock); + vgonel(vp, p); + goto loop; + } + if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p)) { + /* + * It dissappeared, and we may have slept. + * Restart from the beginning + */ + simple_unlock(&spechash_slock); + goto loop; + } + break; + } + /* + * It would be a lot clearer what is going on here if + * this had been expressed as: + * if ( vp && (vp->v_tag == VT_NULL)) + * and the clauses had been swapped. + */ + if (vp == NULL || vp->v_tag != VT_NON) { + /* + * Put the new vnode into the hash chain. + * and if there was an alias, connect them. + */ + MALLOC(nvp->v_specinfo, struct specinfo *, + sizeof(struct specinfo), M_VNODE, M_WAITOK); + nvp->v_rdev = nvp_rdev; + nvp->v_hashchain = vpp; + nvp->v_specnext = *vpp; + nvp->v_specmountpoint = NULL; + simple_unlock(&spechash_slock); + *vpp = nvp; + if (vp != NULLVP) { + nvp->v_flag |= VALIASED; + vp->v_flag |= VALIASED; + vput(vp); + } + return (NULLVP); + } + /* + * if ( vp && (vp->v_tag == VT_NULL)) + * We have a vnode alias, but it is a trashed. + * Make it look like it's newley allocated. (by getnewvnode()) + * The caller should use this instead. + */ + simple_unlock(&spechash_slock); + VOP_UNLOCK(vp, 0, p); + simple_lock(&vp->v_interlock); + vclean(vp, 0, p); + vp->v_op = nvp->v_op; + vp->v_tag = nvp->v_tag; + nvp->v_type = VNON; + insmntque(vp, mp); + return (vp); +} + +/* + * Grab a particular vnode from the free list, increment its + * reference count and lock it. The vnode lock bit is set 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). + */ +int +vget(vp, flags, p) + register struct vnode *vp; + int flags; + struct proc *p; +{ + int error; + + /* + * 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. + */ + if ((flags & LK_INTERLOCK) == 0) { + simple_lock(&vp->v_interlock); + } + if (vp->v_flag & VXLOCK) { + vp->v_flag |= VXWANT; + simple_unlock(&vp->v_interlock); + tsleep((caddr_t)vp, PINOD, "vget", 0); + return (ENOENT); + } + + vp->v_usecount++; + + if (VSHOULDBUSY(vp)) + vbusy(vp); + if (flags & LK_TYPE_MASK) { + if ((error = vn_lock(vp, flags | LK_INTERLOCK, p)) != 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. + */ + simple_lock(&vp->v_interlock); + vp->v_usecount--; + if (VSHOULDFREE(vp)) + vfree(vp); + simple_unlock(&vp->v_interlock); + } + return (error); + } + simple_unlock(&vp->v_interlock); + return (0); +} + +void +vref(struct vnode *vp) +{ + simple_lock(&vp->v_interlock); + vp->v_usecount++; + simple_unlock(&vp->v_interlock); +} + +/* + * Vnode put/release. + * If count drops to zero, call inactive routine and return to freelist. + */ +void +vrele(vp) + struct vnode *vp; +{ + struct proc *p = curproc; /* XXX */ + + KASSERT(vp != NULL, ("vrele: null vp")); + + simple_lock(&vp->v_interlock); + + if (vp->v_usecount > 1) { + + vp->v_usecount--; + simple_unlock(&vp->v_interlock); + + return; + } + + if (vp->v_usecount == 1) { + + vp->v_usecount--; + if (VSHOULDFREE(vp)) + vfree(vp); + /* + * If we are doing a vput, the node is already locked, and we must + * call VOP_INACTIVE with the node locked. So, in the case of + * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. + */ + if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) { + VOP_INACTIVE(vp, p); + } + + } else { +#ifdef DIAGNOSTIC + vprint("vrele: negative ref count", vp); + simple_unlock(&vp->v_interlock); +#endif + panic("vrele: negative ref cnt"); + } +} + +void +vput(vp) + struct vnode *vp; +{ + struct proc *p = curproc; /* XXX */ + + KASSERT(vp != NULL, ("vput: null vp")); + + simple_lock(&vp->v_interlock); + + if (vp->v_usecount > 1) { + + vp->v_usecount--; + VOP_UNLOCK(vp, LK_INTERLOCK, p); + return; + + } + + if (vp->v_usecount == 1) { + + vp->v_usecount--; + if (VSHOULDFREE(vp)) + vfree(vp); + /* + * If we are doing a vput, the node is already locked, and we must + * call VOP_INACTIVE with the node locked. So, in the case of + * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. + */ + simple_unlock(&vp->v_interlock); + VOP_INACTIVE(vp, p); + + } else { +#ifdef DIAGNOSTIC + vprint("vput: negative ref count", vp); +#endif + panic("vput: negative ref cnt"); + } +} + +/* + * Somebody doesn't want the vnode recycled. + */ +void +vhold(vp) + register struct vnode *vp; +{ + int s; + + s = splbio(); + vp->v_holdcnt++; + if (VSHOULDBUSY(vp)) + vbusy(vp); + splx(s); +} + +/* + * One less who cares about this vnode. + */ +void +vdrop(vp) + register struct vnode *vp; +{ + int s; + + s = splbio(); + if (vp->v_holdcnt <= 0) + panic("vdrop: holdcnt"); + vp->v_holdcnt--; + if (VSHOULDFREE(vp)) + vfree(vp); + splx(s); +} + +/* + * Remove any vnodes in the vnode table belonging to mount point mp. + * + * If MNT_NOFORCE is 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 MNT_FORCE is specified, detach any active vnodes + * that are found. + */ +#ifdef DIAGNOSTIC +static int busyprt = 0; /* print out busy vnodes */ +SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); +#endif + +int +vflush(mp, skipvp, flags) + struct mount *mp; + struct vnode *skipvp; + int flags; +{ + struct proc *p = curproc; /* XXX */ + struct vnode *vp, *nvp; + int busy = 0; + + simple_lock(&mntvnode_slock); +loop: + for (vp = mp->mnt_vnodelist.lh_first; vp; vp = nvp) { + /* + * Make sure this vnode wasn't reclaimed in getnewvnode(). + * Start over if it has (it won't be on the list anymore). + */ + if (vp->v_mount != mp) + goto loop; + nvp = vp->v_mntvnodes.le_next; + /* + * Skip over a selected vnode. + */ + if (vp == skipvp) + continue; + + simple_lock(&vp->v_interlock); + /* + * Skip over a vnodes marked VSYSTEM. + */ + if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) { + simple_unlock(&vp->v_interlock); + continue; + } + /* + * If WRITECLOSE is set, only flush out regular file vnodes + * open for writing. + */ + if ((flags & WRITECLOSE) && + (vp->v_writecount == 0 || vp->v_type != VREG)) { + simple_unlock(&vp->v_interlock); + continue; + } + + /* + * 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) { + simple_unlock(&mntvnode_slock); + vgonel(vp, p); + simple_lock(&mntvnode_slock); + continue; + } + + /* + * 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 (flags & FORCECLOSE) { + simple_unlock(&mntvnode_slock); + if (vp->v_type != VBLK && vp->v_type != VCHR) { + vgonel(vp, p); + } else { + vclean(vp, 0, p); + vp->v_op = spec_vnodeop_p; + insmntque(vp, (struct mount *) 0); + } + simple_lock(&mntvnode_slock); + continue; + } +#ifdef DIAGNOSTIC + if (busyprt) + vprint("vflush: busy vnode", vp); +#endif + simple_unlock(&vp->v_interlock); + busy++; + } + simple_unlock(&mntvnode_slock); + if (busy) + return (EBUSY); + return (0); +} + +/* + * Disassociate the underlying file system from a vnode. + */ +static void +vclean(vp, flags, p) + struct vnode *vp; + int flags; + struct proc *p; +{ + int active; + vm_object_t obj; + + /* + * 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; + /* + * 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. + */ + VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, p); + + /* + * Clean out any buffers associated with the vnode. + */ + vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0); + if (obj = vp->v_object) { + if (obj->ref_count == 0) { + /* + * This is a normal way of shutting down the object/vnode + * association. + */ + vm_object_terminate(obj); + } else { + /* + * Woe to the process that tries to page now :-). + */ + vm_pager_deallocate(obj); + } + } + + /* + * 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, NOCRED, p); + VOP_INACTIVE(vp, p); + } 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, 0, p); + } + /* + * Reclaim the vnode. + */ + if (VOP_RECLAIM(vp, p)) + panic("vclean: cannot reclaim"); + + if (active) + vrele(vp); + + cache_purge(vp); + if (vp->v_vnlock) { +#if 0 /* This is the only place we have LK_DRAINED in the entire kernel ??? */ +#ifdef DIAGNOSTIC + if ((vp->v_vnlock->lk_flags & LK_DRAINED) == 0) + vprint("vclean: lock not drained", vp); +#endif +#endif + FREE(vp->v_vnlock, M_VNODE); + vp->v_vnlock = NULL; + } + + if (VSHOULDFREE(vp)) + vfree(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; + if (vp->v_flag & VXWANT) { + vp->v_flag &= ~VXWANT; + wakeup((caddr_t) vp); + } +} + +/* + * 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; + struct proc *p = curproc; /* XXX */ + + KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); + + vp = ap->a_vp; + simple_lock(&vp->v_interlock); + + if (vp->v_flag & VALIASED) { + /* + * 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; + simple_unlock(&vp->v_interlock); + tsleep((caddr_t)vp, PINOD, "vop_revokeall", 0); + return (0); + } + /* + * Ensure that vp will not be vgone'd while we + * are eliminating its aliases. + */ + vp->v_flag |= VXLOCK; + simple_unlock(&vp->v_interlock); + while (vp->v_flag & VALIASED) { + simple_lock(&spechash_slock); + for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { + if (vq->v_rdev != vp->v_rdev || + vq->v_type != vp->v_type || vp == vq) + continue; + simple_unlock(&spechash_slock); + vgone(vq); + break; + } + if (vq == NULLVP) { + simple_unlock(&spechash_slock); + } + } + /* + * Remove the lock so that vgone below will + * really eliminate the vnode after which time + * vgone will awaken any sleepers. + */ + simple_lock(&vp->v_interlock); + vp->v_flag &= ~VXLOCK; + if (vp->v_flag & VXWANT) { + vp->v_flag &= ~VXWANT; + wakeup(vp); + } + } + vgonel(vp, p); + 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(vp, inter_lkp, p) + struct vnode *vp; + struct simplelock *inter_lkp; + struct proc *p; +{ + + simple_lock(&vp->v_interlock); + if (vp->v_usecount == 0) { + if (inter_lkp) { + simple_unlock(inter_lkp); + } + vgonel(vp, p); + return (1); + } + simple_unlock(&vp->v_interlock); + return (0); +} + +/* + * Eliminate all activity associated with a vnode + * in preparation for reuse. + */ +void +vgone(vp) + register struct vnode *vp; +{ + struct proc *p = curproc; /* XXX */ + + simple_lock(&vp->v_interlock); + vgonel(vp, p); +} + +/* + * vgone, with the vp interlock held. + */ +static void +vgonel(vp, p) + struct vnode *vp; + struct proc *p; +{ + int s; + struct vnode *vq; + struct vnode *vx; + + /* + * 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; + simple_unlock(&vp->v_interlock); + tsleep((caddr_t)vp, PINOD, "vgone", 0); + return; + } + + /* + * Clean out the filesystem specific data. + */ + vclean(vp, DOCLOSE, p); + simple_lock(&vp->v_interlock); + + /* + * 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_specinfo != 0) { + simple_lock(&spechash_slock); + if (*vp->v_hashchain == vp) { + *vp->v_hashchain = vp->v_specnext; + } else { + for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { + if (vq->v_specnext != vp) + continue; + vq->v_specnext = vp->v_specnext; + break; + } + if (vq == NULL) + panic("missing bdev"); + } + if (vp->v_flag & VALIASED) { + vx = NULL; + for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { + if (vq->v_rdev != vp->v_rdev || + vq->v_type != vp->v_type) + continue; + if (vx) + break; + vx = vq; + } + if (vx == NULL) + panic("missing alias"); + if (vq == NULL) + vx->v_flag &= ~VALIASED; + vp->v_flag &= ~VALIASED; + } + simple_unlock(&spechash_slock); + FREE(vp->v_specinfo, M_VNODE); + vp->v_specinfo = 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 back + * pointer 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(); + simple_lock(&vnode_free_list_slock); + if (vp->v_flag & VFREE) { + TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); + } else if (vp->v_flag & VTBFREE) { + TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); + vp->v_flag &= ~VTBFREE; + freevnodes++; + } else + freevnodes++; + vp->v_flag |= VFREE; + TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); + simple_unlock(&vnode_free_list_slock); + splx(s); + } + + vp->v_type = VBAD; + simple_unlock(&vp->v_interlock); +} + +/* + * Lookup a vnode by device number. + */ +int +vfinddev(dev, type, vpp) + dev_t dev; + enum vtype type; + struct vnode **vpp; +{ + register struct vnode *vp; + int rc = 0; + + simple_lock(&spechash_slock); + for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) { + if (dev != vp->v_rdev || type != vp->v_type) + continue; + *vpp = vp; + rc = 1; + break; + } + simple_unlock(&spechash_slock); + return (rc); +} + +/* + * Calculate the total number of references to a special device. + */ +int +vcount(vp) + register struct vnode *vp; +{ + struct vnode *vq, *vnext; + int count; + +loop: + if ((vp->v_flag & VALIASED) == 0) + return (vp->v_usecount); + simple_lock(&spechash_slock); + for (count = 0, vq = *vp->v_hashchain; vq; vq = vnext) { + vnext = vq->v_specnext; + if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) + continue; + /* + * Alias, but not in use, so flush it out. + */ + if (vq->v_usecount == 0 && vq != vp) { + simple_unlock(&spechash_slock); + vgone(vq); + goto loop; + } + count += vq->v_usecount; + } + simple_unlock(&spechash_slock); + return (count); +} +/* + * 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; + register 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 & VALIASED) + strcat(buf, "|VALIASED"); + 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 <ddb/ddb.h> +/* + * List all of the locked vnodes in the system. + * Called when debugging the kernel. + */ +DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) +{ + struct proc *p = curproc; /* XXX */ + struct mount *mp, *nmp; + struct vnode *vp; + + printf("Locked vnodes\n"); + simple_lock(&mountlist_slock); + for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { + if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { + nmp = mp->mnt_list.cqe_next; + continue; + } + for (vp = mp->mnt_vnodelist.lh_first; + vp != NULL; + vp = vp->v_mntvnodes.le_next) { + if (VOP_ISLOCKED(vp)) + vprint((char *)0, vp); + } + simple_lock(&mountlist_slock); + nmp = mp->mnt_list.cqe_next; + vfs_unbusy(mp, p); + } + simple_unlock(&mountlist_slock); +} +#endif + +/* + * Top level filesystem related information gathering. + */ +static int sysctl_ovfs_conf __P(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; + 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))); + + simple_lock(&mountlist_slock); + for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { + if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { + nmp = mp->mnt_list.cqe_next; + continue; + } +again: + simple_lock(&mntvnode_slock); + for (vp = mp->mnt_vnodelist.lh_first; + 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) { + simple_unlock(&mntvnode_slock); + goto again; + } + nvp = vp->v_mntvnodes.le_next; + simple_unlock(&mntvnode_slock); + if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || + (error = SYSCTL_OUT(req, vp, VNODESZ))) + return (error); + simple_lock(&mntvnode_slock); + } + simple_unlock(&mntvnode_slock); + simple_lock(&mountlist_slock); + nmp = mp->mnt_list.cqe_next; + vfs_unbusy(mp, p); + } + simple_unlock(&mountlist_slock); + + 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; +{ + struct vnode *vq; + int error = 0; + + if (vp->v_specmountpoint != NULL) + return (EBUSY); + if (vp->v_flag & VALIASED) { + simple_lock(&spechash_slock); + for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { + if (vq->v_rdev != vp->v_rdev || + vq->v_type != vp->v_type) + continue; + if (vq->v_specmountpoint != NULL) { + error = EBUSY; + break; + } + } + simple_unlock(&spechash_slock); + } + return (error); +} + +/* + * Unmount all filesystems. The list is traversed in reverse order + * of mounting to avoid dependencies. + */ +void +vfs_unmountall() +{ + struct mount *mp, *nmp; + struct proc *p; + int error; + + if (curproc != NULL) + p = curproc; + else + p = initproc; /* XXX XXX should this be proc0? */ + /* + * Since this only runs when rebooting, it is not interlocked. + */ + for (mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) { + nmp = mp->mnt_list.cqe_prev; + error = dounmount(mp, MNT_FORCE, p); + if (error) { + printf("unmount of %s failed (", + mp->mnt_stat.f_mntonname); + if (error == EBUSY) + printf("BUSY)\n"); + else + printf("%d)\n", error); + } + } +} + +/* + * 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; +{ + register struct netcred *np; + register struct radix_node_head *rnh; + register 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); + } + 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; +{ + register 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; +{ + register int i; + register 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) + register struct mount *mp; + struct netexport *nep; + struct sockaddr *nam; +{ + register struct netcred *np; + register 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. + */ +void +vfs_msync(struct mount *mp, int flags) { + struct vnode *vp, *nvp; + struct vm_object *obj; + int anyio, tries; + + tries = 5; +loop: + anyio = 0; + for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nvp) { + + nvp = vp->v_mntvnodes.le_next; + + if (vp->v_mount != mp) { + goto loop; + } + + if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ + continue; + + if (flags != MNT_WAIT) { + obj = vp->v_object; + if (obj == NULL || (obj->flags & OBJ_MIGHTBEDIRTY) == 0) + continue; + if (VOP_ISLOCKED(vp)) + continue; + } + + simple_lock(&vp->v_interlock); + if (vp->v_object && + (vp->v_object->flags & OBJ_MIGHTBEDIRTY)) { + if (!vget(vp, + LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) { + if (vp->v_object) { + vm_object_page_clean(vp->v_object, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : 0); + anyio = 1; + } + vput(vp); + } + } else { + simple_unlock(&vp->v_interlock); + } + } + if (anyio && (--tries > 0)) + goto loop; +} + +/* + * 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(vp, p, cred) + struct vnode *vp; + struct proc *p; + struct ucred *cred; +{ + struct vattr vat; + vm_object_t object; + int error = 0; + + if ((vp->v_type != VREG) && (vp->v_type != VBLK)) + return 0; + +retry: + if ((object = vp->v_object) == NULL) { + if (vp->v_type == VREG) { + if ((error = VOP_GETATTR(vp, &vat, cred, p)) != 0) + goto retn; + object = vnode_pager_alloc(vp, vat.va_size, 0, 0); + } else if (major(vp->v_rdev) < nblkdev && + bdevsw[major(vp->v_rdev)] != NULL) { + /* + * This simply allocates the biggest object possible + * for a VBLK vnode. This should be fixed, but doesn't + * cause any problems (yet). + */ + object = vnode_pager_alloc(vp, IDX_TO_OFF(INT_MAX), 0, 0); + } + object->ref_count--; + vp->v_usecount--; + } else { + if (object->flags & OBJ_DEAD) { + VOP_UNLOCK(vp, 0, p); + tsleep(object, PVM, "vodead", 0); + vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + goto retry; + } + } + + if (vp->v_object) + vp->v_flag |= VOBJBUF; + +retn: + return error; +} + +static void +vfree(vp) + struct vnode *vp; +{ + int s; + + s = splbio(); + simple_lock(&vnode_free_list_slock); + if (vp->v_flag & VTBFREE) { + TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); + vp->v_flag &= ~VTBFREE; + } + 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++; + simple_unlock(&vnode_free_list_slock); + vp->v_flag &= ~VAGE; + vp->v_flag |= VFREE; + splx(s); +} + +void +vbusy(vp) + struct vnode *vp; +{ + int s; + + s = splbio(); + simple_lock(&vnode_free_list_slock); + if (vp->v_flag & VTBFREE) { + TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); + vp->v_flag &= ~VTBFREE; + } else { + TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); + freevnodes--; + } + simple_unlock(&vnode_free_list_slock); + vp->v_flag &= ~(VFREE|VAGE); + splx(s); +} + +/* + * 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(vp, p, events) + struct vnode *vp; + struct proc *p; + short events; +{ + simple_lock(&vp->v_pollinfo.vpi_lock); + 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; + + simple_unlock(&vp->v_pollinfo.vpi_lock); + return events; + } + vp->v_pollinfo.vpi_events |= events; + selrecord(p, &vp->v_pollinfo.vpi_selinfo); + simple_unlock(&vp->v_pollinfo.vpi_lock); + 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; +{ + simple_lock(&vp->v_pollinfo.vpi_lock); + 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); + } + simple_unlock(&vp->v_pollinfo.vpi_lock); +} + +/* + * 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; +{ + simple_lock(&vp->v_pollinfo.vpi_lock); + if (vp->v_pollinfo.vpi_events) { + vp->v_pollinfo.vpi_events = 0; + selwakeup(&vp->v_pollinfo.vpi_selinfo); + } + simple_unlock(&vp->v_pollinfo.vpi_lock); +} + + + +/* + * Routine to create and manage a filesystem syncer vnode. + */ +#define sync_close ((int (*) __P((struct vop_close_args *)))nullop) +static int sync_fsync __P((struct vop_fsync_args *)); +static int sync_inactive __P((struct vop_inactive_args *)); +static int sync_reclaim __P((struct vop_reclaim_args *)); +#define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock) +#define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock) +static int sync_print __P((struct vop_print_args *)); +#define sync_islocked ((int(*) __P((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. + */ +int +vfs_allocate_syncvnode(mp) + 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 proc *a_p; + } */ *ap; +{ + struct vnode *syncvp = ap->a_vp; + struct mount *mp = syncvp->v_mount; + struct proc *p = ap->a_p; + 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. + */ + simple_lock(&mountlist_slock); + if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_slock, p) != 0) { + simple_unlock(&mountlist_slock); + return (0); + } + asyncflag = mp->mnt_flag & MNT_ASYNC; + mp->mnt_flag &= ~MNT_ASYNC; + vfs_msync(mp, MNT_NOWAIT); + VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p); + if (asyncflag) + mp->mnt_flag |= MNT_ASYNC; + vfs_unbusy(mp, p); + 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. + */ +static int +sync_reclaim(ap) + struct vop_reclaim_args /* { + struct vnode *a_vp; + } */ *ap; +{ + struct vnode *vp = ap->a_vp; + + vp->v_mount->mnt_syncer = NULL; + if (vp->v_flag & VONWORKLST) { + LIST_REMOVE(vp, v_synclist); + vp->v_flag &= ~VONWORKLST; + } + + 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); +} |
