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-rw-r--r--sys/kern/vfs_subr.c1782
1 files changed, 1782 insertions, 0 deletions
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
new file mode 100644
index 000000000000..f891e02d519e
--- /dev/null
+++ b/sys/kern/vfs_subr.c
@@ -0,0 +1,1782 @@
+/*
+ * 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
+ */
+
+/*
+ * External virtual filesystem routines
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/mount.h>
+#include <sys/time.h>
+#include <sys/vnode.h>
+#include <sys/stat.h>
+#include <sys/namei.h>
+#include <sys/ucred.h>
+#include <sys/buf.h>
+#include <sys/errno.h>
+#include <sys/malloc.h>
+#include <sys/domain.h>
+#include <sys/mbuf.h>
+
+#include <vm/vm.h>
+#include <sys/sysctl.h>
+
+#include <miscfs/specfs/specdev.h>
+
+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,
+};
+
+/*
+ * Insq/Remq for the vnode usage lists.
+ */
+#define bufinsvn(bp, dp) LIST_INSERT_HEAD(dp, bp, b_vnbufs)
+#define bufremvn(bp) { \
+ LIST_REMOVE(bp, b_vnbufs); \
+ (bp)->b_vnbufs.le_next = NOLIST; \
+}
+TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */
+struct mntlist mountlist; /* mounted filesystem list */
+struct simplelock mountlist_slock;
+static struct simplelock mntid_slock;
+struct simplelock mntvnode_slock;
+struct simplelock vnode_free_list_slock;
+static struct simplelock spechash_slock;
+
+/*
+ * Initialize the vnode management data structures.
+ */
+void
+vntblinit()
+{
+
+ simple_lock_init(&mntvnode_slock);
+ simple_lock_init(&mntid_slock);
+ simple_lock_init(&spechash_slock);
+ TAILQ_INIT(&vnode_free_list);
+ simple_lock_init(&vnode_free_list_slock);
+ CIRCLEQ_INIT(&mountlist);
+}
+
+/*
+ * 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_flag & MNT_UNMOUNT) {
+ if (flags & LK_NOWAIT)
+ return (ENOENT);
+ mp->mnt_flag |= MNT_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.
+ */
+ sleep((caddr_t)mp, PVFS);
+ if (interlkp)
+ simple_lock(interlkp);
+ return (ENOENT);
+ }
+ lkflags = LK_SHARED;
+ 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;
+
+ 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, 0);
+ (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] = '/';
+ (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.
+ */
+int
+vfs_mountroot()
+{
+ struct vfsconf *vfsp;
+ extern int (*mountroot)(void);
+ int error;
+
+ if (mountroot != NULL)
+ return ((*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);
+}
+
+/*
+ * 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 = vap->va_bytes = VNOVAL;
+ vap->va_mode = vap->va_nlink = vap->va_uid = vap->va_gid =
+ vap->va_fsid = vap->va_fileid =
+ vap->va_blocksize = vap->va_rdev =
+ vap->va_atime.ts_sec = vap->va_atime.ts_nsec =
+ vap->va_mtime.ts_sec = vap->va_mtime.ts_nsec =
+ vap->va_ctime.ts_sec = vap->va_ctime.ts_nsec =
+ vap->va_flags = vap->va_gen = VNOVAL;
+ vap->va_vaflags = 0;
+}
+
+/*
+ * Routines having to do with the management of the vnode table.
+ */
+extern int (**dead_vnodeop_p)();
+static void vclean __P((struct vnode *vp, int flag, struct proc *p));
+extern void vgonel __P((struct vnode *vp, struct proc *p));
+long numvnodes;
+extern struct vattr va_null;
+
+/*
+ * Return the next vnode from the free list.
+ */
+int
+getnewvnode(tag, mp, vops, vpp)
+ enum vtagtype tag;
+ struct mount *mp;
+ int (**vops)();
+ struct vnode **vpp;
+{
+ struct proc *p = curproc; /* XXX */
+ struct vnode *vp;
+ int s;
+ int cnt;
+
+top:
+ simple_lock(&vnode_free_list_slock);
+ if ((vnode_free_list.tqh_first == NULL &&
+ numvnodes < 2 * desiredvnodes) ||
+ numvnodes < desiredvnodes) {
+ simple_unlock(&vnode_free_list_slock);
+ vp = (struct vnode *)malloc((u_long)sizeof *vp,
+ M_VNODE, M_WAITOK);
+ bzero((char *)vp, sizeof *vp);
+ numvnodes++;
+ } else {
+ for (vp = vnode_free_list.tqh_first;
+ vp != NULLVP; vp = vp->v_freelist.tqe_next) {
+ if (simple_lock_try(&vp->v_interlock))
+ break;
+ }
+ /*
+ * Unless this is a bad time of the month, at most
+ * the first NCPUS items on the free list are
+ * locked, so this is close enough to being empty.
+ */
+ if (vp == NULLVP) {
+ simple_unlock(&vnode_free_list_slock);
+ tablefull("vnode");
+ *vpp = 0;
+ return (ENFILE);
+ }
+ if (vp->v_usecount)
+ panic("free vnode isn't");
+ TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+ /* see comment on why 0xdeadb is set at end of vgone (below) */
+ vp->v_freelist.tqe_prev = (struct vnode **)0xdeadb;
+ simple_unlock(&vnode_free_list_slock);
+ vp->v_lease = NULL;
+ if (vp->v_type != VBAD)
+ vgonel(vp, p);
+ else
+ simple_unlock(&vp->v_interlock);
+#ifdef DIAGNOSTIC
+ 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_ralen = 0;
+ vp->v_maxra = 0;
+ vp->v_lastw = 0;
+ vp->v_lasta = 0;
+ vp->v_cstart = 0;
+ vp->v_clen = 0;
+ vp->v_socket = 0;
+ }
+ vp->v_type = VNON;
+ cache_purge(vp);
+ vp->v_tag = tag;
+ vp->v_op = vops;
+ insmntque(vp, mp);
+ *vpp = vp;
+ vp->v_usecount = 1;
+ vp->v_data = 0;
+ return (0);
+}
+
+/*
+ * Move a vnode from one mount queue to another.
+ */
+void
+insmntque(vp, mp)
+ struct vnode *vp;
+ 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)
+ 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) {
+ if (--vp->v_numoutput < 0)
+ panic("vwakeup: neg numoutput");
+ if ((vp->v_flag & VBWAIT) && vp->v_numoutput <= 0) {
+ if (vp->v_numoutput < 0)
+ panic("vwakeup: neg numoutput 2");
+ 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;
+
+ if (flags & V_SAVE) {
+ if (error = VOP_FSYNC(vp, cred, MNT_WAIT, p))
+ return (error);
+ if (vp->v_dirtyblkhd.lh_first != NULL)
+ panic("vinvalbuf: dirty bufs");
+ }
+ for (;;) {
+ if ((blist = vp->v_cleanblkhd.lh_first) && flags & V_SAVEMETA)
+ while (blist && blist->b_lblkno < 0)
+ blist = blist->b_vnbufs.le_next;
+ if (!blist && (blist = vp->v_dirtyblkhd.lh_first) &&
+ (flags & V_SAVEMETA))
+ while (blist && blist->b_lblkno < 0)
+ blist = blist->b_vnbufs.le_next;
+ if (!blist)
+ break;
+
+ for (bp = blist; bp; bp = nbp) {
+ nbp = bp->b_vnbufs.le_next;
+ if (flags & V_SAVEMETA && bp->b_lblkno < 0)
+ continue;
+ s = splbio();
+ if (bp->b_flags & B_BUSY) {
+ bp->b_flags |= B_WANTED;
+ error = tsleep((caddr_t)bp,
+ slpflag | (PRIBIO + 1), "vinvalbuf",
+ slptimeo);
+ splx(s);
+ if (error)
+ return (error);
+ break;
+ }
+ bremfree(bp);
+ bp->b_flags |= B_BUSY;
+ splx(s);
+ /*
+ * 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.
+ */
+ if ((bp->b_flags & B_DELWRI) && (flags & V_SAVE)) {
+ (void) VOP_BWRITE(bp);
+ break;
+ }
+ bp->b_flags |= B_INVAL;
+ brelse(bp);
+ }
+ }
+ if (!(flags & V_SAVEMETA) &&
+ (vp->v_dirtyblkhd.lh_first || vp->v_cleanblkhd.lh_first))
+ panic("vinvalbuf: flush failed");
+ return (0);
+}
+
+/*
+ * Associate a buffer with a vnode.
+ */
+void
+bgetvp(vp, bp)
+ register struct vnode *vp;
+ register struct buf *bp;
+{
+
+ if (bp->b_vp)
+ panic("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.
+ */
+ bufinsvn(bp, &vp->v_cleanblkhd);
+}
+
+/*
+ * Disassociate a buffer from a vnode.
+ */
+void
+brelvp(bp)
+ register struct buf *bp;
+{
+ struct vnode *vp;
+
+ if (bp->b_vp == (struct vnode *) 0)
+ panic("brelvp: NULL");
+ /*
+ * Delete from old vnode list, if on one.
+ */
+ if (bp->b_vnbufs.le_next != NOLIST)
+ bufremvn(bp);
+ vp = bp->b_vp;
+ bp->b_vp = (struct vnode *) 0;
+ HOLDRELE(vp);
+}
+
+/*
+ * 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;
+{
+ register struct buflists *listheadp;
+
+ if (newvp == NULL) {
+ printf("reassignbuf: NULL");
+ return;
+ }
+ /*
+ * Delete from old vnode list, if on one.
+ */
+ if (bp->b_vnbufs.le_next != NOLIST)
+ bufremvn(bp);
+ /*
+ * If dirty, put on list of dirty buffers;
+ * otherwise insert onto list of clean buffers.
+ */
+ if (bp->b_flags & B_DELWRI)
+ listheadp = &newvp->v_dirtyblkhd;
+ else
+ listheadp = &newvp->v_cleanblkhd;
+ bufinsvn(bp, listheadp);
+}
+
+/*
+ * Create a vnode for a block device.
+ * Used for root filesystem, argdev, and swap areas.
+ * Also used for memory file system special devices.
+ */
+int
+bdevvp(dev, vpp)
+ dev_t dev;
+ struct vnode **vpp;
+{
+ register struct vnode *vp;
+ struct vnode *nvp;
+ int error;
+
+ if (dev == NODEV) {
+ *vpp = NULLVP;
+ return (ENODEV);
+ }
+ 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)) {
+ 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.
+ */
+ 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)) {
+ simple_unlock(&spechash_slock);
+ goto loop;
+ }
+ break;
+ }
+ if (vp == NULL || vp->v_tag != VT_NON) {
+ 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_specflags = 0;
+ simple_unlock(&spechash_slock);
+ *vpp = nvp;
+ if (vp != NULLVP) {
+ nvp->v_flag |= VALIASED;
+ vp->v_flag |= VALIASED;
+ vput(vp);
+ }
+ return (NULLVP);
+ }
+ 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)
+ 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);
+ }
+ if (vp->v_usecount == 0) {
+ simple_lock(&vnode_free_list_slock);
+ TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+ simple_unlock(&vnode_free_list_slock);
+ }
+ vp->v_usecount++;
+ if (flags & LK_TYPE_MASK) {
+ if (error = vn_lock(vp, flags | LK_INTERLOCK, p))
+ vrele(vp);
+ return (error);
+ }
+ simple_unlock(&vp->v_interlock);
+ return (0);
+}
+
+/*
+ * Stubs to use when there is no locking to be done on the underlying object.
+ * A minimal shared lock is necessary to ensure that the underlying object
+ * is not revoked while an operation is in progress. So, an active shared
+ * count is maintained in an auxillary vnode lock structure.
+ */
+int
+vop_nolock(ap)
+ struct vop_lock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+#ifdef notyet
+ /*
+ * This code cannot be used until all the non-locking filesystems
+ * (notably NFS) are converted to properly lock and release nodes.
+ * Also, certain vnode operations change the locking state within
+ * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
+ * and symlink). Ideally these operations should not change the
+ * lock state, but should be changed to let the caller of the
+ * function unlock them. Otherwise all intermediate vnode layers
+ * (such as union, umapfs, etc) must catch these functions to do
+ * the necessary locking at their layer. Note that the inactive
+ * and lookup operations also change their lock state, but this
+ * cannot be avoided, so these two operations will always need
+ * to be handled in intermediate layers.
+ */
+ struct vnode *vp = ap->a_vp;
+ int vnflags, flags = ap->a_flags;
+
+ if (vp->v_vnlock == NULL) {
+ if ((flags & LK_TYPE_MASK) == LK_DRAIN)
+ return (0);
+ MALLOC(vp->v_vnlock, struct lock *, sizeof(struct lock),
+ M_VNODE, M_WAITOK);
+ lockinit(vp->v_vnlock, PVFS, "vnlock", 0, 0);
+ }
+ switch (flags & LK_TYPE_MASK) {
+ case LK_DRAIN:
+ vnflags = LK_DRAIN;
+ break;
+ case LK_EXCLUSIVE:
+ case LK_SHARED:
+ vnflags = LK_SHARED;
+ break;
+ case LK_UPGRADE:
+ case LK_EXCLUPGRADE:
+ case LK_DOWNGRADE:
+ return (0);
+ case LK_RELEASE:
+ default:
+ panic("vop_nolock: bad operation %d", flags & LK_TYPE_MASK);
+ }
+ if (flags & LK_INTERLOCK)
+ vnflags |= LK_INTERLOCK;
+ return(lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
+#else /* for now */
+ /*
+ * Since we are not using the lock manager, we must clear
+ * the interlock here.
+ */
+ if (ap->a_flags & LK_INTERLOCK)
+ simple_unlock(&ap->a_vp->v_interlock);
+ return (0);
+#endif
+}
+
+/*
+ * Decrement the active use count.
+ */
+int
+vop_nounlock(ap)
+ struct vop_unlock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+ struct vnode *vp = ap->a_vp;
+
+ if (vp->v_vnlock == NULL)
+ return (0);
+ return (lockmgr(vp->v_vnlock, LK_RELEASE, NULL, ap->a_p));
+}
+
+/*
+ * Return whether or not the node is in use.
+ */
+int
+vop_noislocked(ap)
+ struct vop_islocked_args /* {
+ struct vnode *a_vp;
+ } */ *ap;
+{
+ struct vnode *vp = ap->a_vp;
+
+ if (vp->v_vnlock == NULL)
+ return (0);
+ return (lockstatus(vp->v_vnlock));
+}
+
+/*
+ * Vnode reference.
+ */
+void
+vref(vp)
+ struct vnode *vp;
+{
+
+ simple_lock(&vp->v_interlock);
+ if (vp->v_usecount <= 0)
+ panic("vref used where vget required");
+ vp->v_usecount++;
+ simple_unlock(&vp->v_interlock);
+}
+
+/*
+ * vput(), just unlock and vrele()
+ */
+void
+vput(vp)
+ struct vnode *vp;
+{
+ struct proc *p = curproc; /* XXX */
+
+#ifdef DIGANOSTIC
+ if (vp == NULL)
+ panic("vput: null vp");
+#endif
+ simple_lock(&vp->v_interlock);
+ vp->v_usecount--;
+ if (vp->v_usecount > 0) {
+ simple_unlock(&vp->v_interlock);
+ VOP_UNLOCK(vp, 0, p);
+ return;
+ }
+#ifdef DIAGNOSTIC
+ if (vp->v_usecount < 0 || vp->v_writecount != 0) {
+ vprint("vput: bad ref count", vp);
+ panic("vput: ref cnt");
+ }
+#endif
+ /*
+ * insert at tail of LRU list
+ */
+ simple_lock(&vnode_free_list_slock);
+ TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
+ simple_unlock(&vnode_free_list_slock);
+ simple_unlock(&vp->v_interlock);
+ VOP_INACTIVE(vp, p);
+}
+
+/*
+ * Vnode release.
+ * If count drops to zero, call inactive routine and return to freelist.
+ */
+void
+vrele(vp)
+ struct vnode *vp;
+{
+ struct proc *p = curproc; /* XXX */
+
+#ifdef DIAGNOSTIC
+ if (vp == NULL)
+ panic("vrele: null vp");
+#endif
+ simple_lock(&vp->v_interlock);
+ vp->v_usecount--;
+ if (vp->v_usecount > 0) {
+ simple_unlock(&vp->v_interlock);
+ return;
+ }
+#ifdef DIAGNOSTIC
+ if (vp->v_usecount < 0 || vp->v_writecount != 0) {
+ vprint("vrele: bad ref count", vp);
+ panic("vrele: ref cnt");
+ }
+#endif
+ /*
+ * insert at tail of LRU list
+ */
+ simple_lock(&vnode_free_list_slock);
+ TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
+ simple_unlock(&vnode_free_list_slock);
+ if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0)
+ VOP_INACTIVE(vp, p);
+}
+
+#ifdef DIAGNOSTIC
+/*
+ * Page or buffer structure gets a reference.
+ */
+void
+vhold(vp)
+ register struct vnode *vp;
+{
+
+ simple_lock(&vp->v_interlock);
+ vp->v_holdcnt++;
+ simple_unlock(&vp->v_interlock);
+}
+
+/*
+ * Page or buffer structure frees a reference.
+ */
+void
+holdrele(vp)
+ register struct vnode *vp;
+{
+
+ simple_lock(&vp->v_interlock);
+ if (vp->v_holdcnt <= 0)
+ panic("holdrele: holdcnt");
+ vp->v_holdcnt--;
+ simple_unlock(&vp->v_interlock);
+}
+#endif /* DIAGNOSTIC */
+
+/*
+ * 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
+int busyprt = 0; /* print out busy vnodes */
+struct ctldebug debug1 = { "busyprt", &busyprt };
+#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) {
+ 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.
+ * The vnode interlock is held on entry.
+ */
+static void
+vclean(vp, flags, p)
+ struct vnode *vp;
+ int flags;
+ struct proc *p;
+{
+ 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;
+ /*
+ * 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.
+ */
+ if (flags & DOCLOSE)
+ vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0);
+ /*
+ * 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, IO_NDELAY, 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 ((vp->v_vnlock->lk_flags & LK_DRAINED) == 0)
+ vprint("vclean: lock not drained", vp);
+ FREE(vp->v_vnlock, M_VNODE);
+ vp->v_vnlock = NULL;
+ }
+
+ /*
+ * Done with purge, notify sleepers of the grim news.
+ */
+ vp->v_op = dead_vnodeop_p;
+ 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 */
+
+#ifdef DIAGNOSTIC
+ if ((ap->a_flags & REVOKEALL) == 0)
+ panic("vop_revoke");
+#endif
+
+ 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;
+ }
+ 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)
+ struct vnode *vp;
+{
+ struct proc *p = curproc; /* XXX */
+
+ simple_lock(&vp->v_interlock);
+ vgonel(vp, p);
+}
+
+/*
+ * vgone, with the vp interlock held.
+ */
+void
+vgonel(vp, p)
+ struct vnode *vp;
+ struct proc *p;
+{
+ 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);
+ /*
+ * 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.
+ * So, the back pointer is explicitly set to `0xdeadb' in
+ * getnewvnode after removing it from the freelist to ensure
+ * that we do not try to move it here.
+ */
+ if (vp->v_usecount == 0) {
+ simple_lock(&vnode_free_list_slock);
+ if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) &&
+ vnode_free_list.tqh_first != vp) {
+ TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+ TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
+ }
+ simple_unlock(&vnode_free_list_slock);
+ }
+ vp->v_type = VBAD;
+}
+
+/*
+ * Lookup a vnode by device number.
+ */
+int
+vfinddev(dev, type, vpp)
+ dev_t dev;
+ enum vtype type;
+ struct vnode **vpp;
+{
+ 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)
+ 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[64];
+
+ if (label != NULL)
+ printf("%s: ", label);
+ 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 (buf[0] != '\0')
+ printf(" flags (%s)", &buf[1]);
+ if (vp->v_data == NULL) {
+ printf("\n");
+ } else {
+ printf("\n\t");
+ VOP_PRINT(vp);
+ }
+}
+
+#ifdef DEBUG
+/*
+ * List all of the locked vnodes in the system.
+ * Called when debugging the kernel.
+ */
+void
+printlockedvnodes()
+{
+ 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.
+ */
+int
+vfs_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
+ int *name;
+ u_int namelen;
+ void *oldp;
+ size_t *oldlenp;
+ void *newp;
+ size_t newlen;
+ struct proc *p;
+{
+ struct ctldebug *cdp;
+ struct vfsconf *vfsp;
+
+ /* 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));
+ }
+ switch (name[1]) {
+ case VFS_MAXTYPENUM:
+ return (sysctl_rdint(oldp, oldlenp, newp, maxvfsconf));
+ 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_rdstruct(oldp, oldlenp, newp, vfsp,
+ sizeof(struct vfsconf)));
+ }
+ return (EOPNOTSUPP);
+}
+
+int kinfo_vdebug = 1;
+int kinfo_vgetfailed;
+#define KINFO_VNODESLOP 10
+/*
+ * Dump vnode list (via sysctl).
+ * Copyout address of vnode followed by vnode.
+ */
+/* ARGSUSED */
+int
+sysctl_vnode(where, sizep, p)
+ char *where;
+ size_t *sizep;
+ struct proc *p;
+{
+ struct mount *mp, *nmp;
+ struct vnode *nvp, *vp;
+ char *bp = where, *savebp;
+ char *ewhere;
+ int error;
+
+#define VPTRSZ sizeof (struct vnode *)
+#define VNODESZ sizeof (struct vnode)
+ if (where == NULL) {
+ *sizep = (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ);
+ return (0);
+ }
+ ewhere = where + *sizep;
+
+ 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;
+ }
+ savebp = bp;
+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);
+ if (kinfo_vdebug)
+ printf("kinfo: vp changed\n");
+ bp = savebp;
+ goto again;
+ }
+ nvp = vp->v_mntvnodes.le_next;
+ if (bp + VPTRSZ + VNODESZ > ewhere) {
+ simple_unlock(&mntvnode_slock);
+ *sizep = bp - where;
+ return (ENOMEM);
+ }
+ simple_unlock(&mntvnode_slock);
+ if ((error = copyout((caddr_t)&vp, bp, VPTRSZ)) ||
+ (error = copyout((caddr_t)vp, bp + VPTRSZ, VNODESZ)))
+ return (error);
+ bp += VPTRSZ + VNODESZ;
+ 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);
+
+ *sizep = bp - where;
+ return (0);
+}
+
+/*
+ * 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_specflags & SI_MOUNTEDON)
+ 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_specflags & SI_MOUNTEDON) {
+ 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 = curproc; /* XXX */
+
+ /*
+ * 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;
+ (void) dounmount(mp, MNT_FORCE, p);
+ }
+}
+
+/*
+ * 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_addr, (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) {
+ /*
+ * One of the reasons that rnh_addaddr may fail is that
+ * the entry already exists. To check for this case, we
+ * look up the entry to see if it is there. If so, we
+ * do not need to make a new entry but do return success.
+ */
+ free(np, M_NETADDR);
+ rn = (*rnh->rnh_matchaddr)((caddr_t)saddr, rnh);
+ if (rn != 0 && (rn->rn_flags & RNF_ROOT) == 0 &&
+ ((struct netcred *)rn)->netc_exflags == argp->ex_flags &&
+ !bcmp((caddr_t)&((struct netcred *)rn)->netc_anon,
+ (caddr_t)&argp->ex_anon, sizeof(struct ucred)))
+ return (0);
+ return (EPERM);
+ }
+ 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;
+ caddr_t 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) {
+ vfs_free_addrlist(nep);
+ mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED);
+ }
+ if (argp->ex_flags & MNT_EXPORTED) {
+ if (error = vfs_hang_addrlist(mp, nep, argp))
+ return (error);
+ mp->mnt_flag |= MNT_EXPORTED;
+ }
+ return (0);
+}
+
+struct netcred *
+vfs_export_lookup(mp, nep, nam)
+ register struct mount *mp;
+ struct netexport *nep;
+ struct mbuf *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 = mtod(nam, struct sockaddr *);
+ 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);
+}