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NetBSD/sys/kern/vfs_subr2.c
ad 42d0626726 PR kern/38141 lookup/vfs_busy acquire rwlock recursively 
Simplify the mount locking. Remove all the crud to deal with recursion on
the mount lock, and crud to deal with unmount as another weirdo lock.

Hopefully this will once and for all fix the deadlocks with this. With this
commit there are two locks on each mount:

- krwlock_t mnt_unmounting. This is used to prevent unmount across critical
  sections like getnewvnode(). It's only ever read locked with rw_tryenter(),
  and is only ever write locked in dounmount(). A write hold can't be taken
  on this lock if the current LWP could hold a vnode lock.

- kmutex_t mnt_updating. This is taken by threads updating the mount, for
  example when going r/o -> r/w, and is only present to serialize updates.
  In order to take this lock, a read hold must first be taken on
  mnt_unmounting, and the two need to be held across the operation.

One effect of this change: previously if an unmount failed, we would make a
half hearted attempt to back out of it gracefully, but that was unlikely to
work in a lot of cases. Now while an unmount that will be aborted is in
progress, new file operations within the mount will fail instead of being
delayed. That is unlikely to be a problem though, because if the admin
requests unmount of a file system then s(he) has made a decision to deny
access to the resource.
2008-05-06 18:43:44 +00:00

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/* $NetBSD: vfs_subr2.c,v 1.24 2008/05/06 18:43:44 ad Exp $ */
/*-
* Copyright (c) 1997, 1998, 2004, 2005, 2007, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center, by Charles M. Hannum, and by Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* 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. 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 8.13 (Berkeley) 4/18/94
*/
/*
* External virtual filesystem routines.
*
* This file contains vfs subroutines which do not heavily depend on
* the kernel environment and are therefore suitable to be compiled
* outside of the kernel.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: vfs_subr2.c,v 1.24 2008/05/06 18:43:44 ad Exp $");
#include "opt_ddb.h"
#include <sys/param.h>
#include <sys/filedesc.h>
#include <sys/kauth.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/proc.h>
#include <sys/kthread.h>
#include <sys/atomic.h>
#include <miscfs/syncfs/syncfs.h>
#include <miscfs/specfs/specdev.h>
#include <uvm/uvm_ddb.h>
const enum vtype iftovt_tab[16] = {
VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD,
};
const 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; \
}
int doforce = 1; /* 1 => permit forcible unmounting */
int prtactive = 0; /* 1 => print out reclaim of active vnodes */
kmutex_t mountlist_lock;
kmutex_t mntid_lock;
kmutex_t mntvnode_lock;
kmutex_t vnode_free_list_lock;
kmutex_t specfs_lock;
kmutex_t vfs_list_lock;
struct mntlist mountlist = /* mounted filesystem list */
CIRCLEQ_HEAD_INITIALIZER(mountlist);
static specificdata_domain_t mount_specificdata_domain;
/*
* These define the root filesystem and device.
*/
struct vnode *rootvnode;
struct device *root_device; /* root device */
#ifdef DEBUG
void printlockedvnodes(void);
#endif
u_int numvnodes;
/*
* Initialize the vnode management data structures.
*/
void
vntblinit(void)
{
mutex_init(&mountlist_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&mntid_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&mntvnode_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&vnode_free_list_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&specfs_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&vfs_list_lock, MUTEX_DEFAULT, IPL_NONE);
mount_specificdata_domain = specificdata_domain_create();
/* Initialize the filesystem syncer. */
vn_initialize_syncerd();
vn_init1();
}
/*
* Lookup a mount point by filesystem identifier.
*
* XXX Needs to add a reference to the mount point.
*/
struct mount *
vfs_getvfs(fsid_t *fsid)
{
struct mount *mp;
mutex_enter(&mountlist_lock);
CIRCLEQ_FOREACH(mp, &mountlist, mnt_list) {
if (mp->mnt_stat.f_fsidx.__fsid_val[0] == fsid->__fsid_val[0] &&
mp->mnt_stat.f_fsidx.__fsid_val[1] == fsid->__fsid_val[1]) {
mutex_exit(&mountlist_lock);
return (mp);
}
}
mutex_exit(&mountlist_lock);
return ((struct mount *)0);
}
/*
* Drop a reference to a mount structure, freeing if the last reference.
*/
void
vfs_destroy(struct mount *mp)
{
if (__predict_true(atomic_dec_uint_nv(&mp->mnt_refcnt) > 0)) {
return;
}
/*
* Nothing else has visibility of the mount: we can now
* free the data structures.
*/
specificdata_fini(mount_specificdata_domain, &mp->mnt_specdataref);
rw_destroy(&mp->mnt_unmounting);
mutex_destroy(&mp->mnt_updating);
mutex_destroy(&mp->mnt_renamelock);
if (mp->mnt_op != NULL) {
vfs_delref(mp->mnt_op);
}
kmem_free(mp, sizeof(*mp));
}
/*
* Wait for a vnode (typically with VI_XLOCK set) to be cleaned or
* recycled.
*/
void
vwait(vnode_t *vp, int flags)
{
KASSERT(mutex_owned(&vp->v_interlock));
KASSERT(vp->v_usecount != 0);
while ((vp->v_iflag & flags) != 0)
cv_wait(&vp->v_cv, &vp->v_interlock);
}
/*
* Insert a marker vnode into a mount's vnode list, after the
* specified vnode. mntvnode_lock must be held.
*/
void
vmark(vnode_t *mvp, vnode_t *vp)
{
struct mount *mp;
mp = mvp->v_mount;
KASSERT(mutex_owned(&mntvnode_lock));
KASSERT((mvp->v_iflag & VI_MARKER) != 0);
KASSERT(vp->v_mount == mp);
TAILQ_INSERT_AFTER(&mp->mnt_vnodelist, vp, mvp, v_mntvnodes);
}
/*
* Remove a marker vnode from a mount's vnode list, and return
* a pointer to the next vnode in the list. mntvnode_lock must
* be held.
*/
vnode_t *
vunmark(vnode_t *mvp)
{
vnode_t *vp;
struct mount *mp;
mp = mvp->v_mount;
KASSERT(mutex_owned(&mntvnode_lock));
KASSERT((mvp->v_iflag & VI_MARKER) != 0);
vp = TAILQ_NEXT(mvp, v_mntvnodes);
TAILQ_REMOVE(&mp->mnt_vnodelist, mvp, v_mntvnodes);
KASSERT(vp == NULL || vp->v_mount == mp);
return vp;
}
/*
* Update outstanding I/O count and do wakeup if requested.
*/
void
vwakeup(struct buf *bp)
{
struct vnode *vp;
if ((vp = bp->b_vp) == NULL)
return;
KASSERT(bp->b_objlock == &vp->v_interlock);
KASSERT(mutex_owned(bp->b_objlock));
if (--vp->v_numoutput < 0)
panic("vwakeup: neg numoutput, vp %p", vp);
if (vp->v_numoutput == 0)
cv_broadcast(&vp->v_cv);
}
/*
* Flush out and invalidate all buffers associated with a vnode.
* Called with the underlying vnode locked, which should prevent new dirty
* buffers from being queued.
*/
int
vinvalbuf(struct vnode *vp, int flags, kauth_cred_t cred, struct lwp *l,
bool catch, int slptimeo)
{
struct buf *bp, *nbp;
int error;
int flushflags = PGO_ALLPAGES | PGO_FREE | PGO_SYNCIO |
(flags & V_SAVE ? PGO_CLEANIT | PGO_RECLAIM : 0);
/* XXXUBC this doesn't look at flags or slp* */
mutex_enter(&vp->v_interlock);
error = VOP_PUTPAGES(vp, 0, 0, flushflags);
if (error) {
return error;
}
if (flags & V_SAVE) {
error = VOP_FSYNC(vp, cred, FSYNC_WAIT|FSYNC_RECLAIM, 0, 0);
if (error)
return (error);
KASSERT(vp->v_numoutput == 0 && LIST_EMPTY(&vp->v_dirtyblkhd));
}
mutex_enter(&bufcache_lock);
restart:
for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
error = bbusy(bp, catch, slptimeo, NULL);
if (error != 0) {
if (error == EPASSTHROUGH)
goto restart;
mutex_exit(&bufcache_lock);
return (error);
}
brelsel(bp, BC_INVAL | BC_VFLUSH);
}
for (bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
error = bbusy(bp, catch, slptimeo, NULL);
if (error != 0) {
if (error == EPASSTHROUGH)
goto restart;
mutex_exit(&bufcache_lock);
return (error);
}
/*
* XXX Since there are no node locks for NFS, I believe
* there is a slight chance that a delayed write will
* occur while sleeping just above, so check for it.
*/
if ((bp->b_oflags & BO_DELWRI) && (flags & V_SAVE)) {
#ifdef DEBUG
printf("buffer still DELWRI\n");
#endif
bp->b_cflags |= BC_BUSY | BC_VFLUSH;
mutex_exit(&bufcache_lock);
VOP_BWRITE(bp);
mutex_enter(&bufcache_lock);
goto restart;
}
brelsel(bp, BC_INVAL | BC_VFLUSH);
}
#ifdef DIAGNOSTIC
if (!LIST_EMPTY(&vp->v_cleanblkhd) || !LIST_EMPTY(&vp->v_dirtyblkhd))
panic("vinvalbuf: flush failed, vp %p", vp);
#endif
mutex_exit(&bufcache_lock);
return (0);
}
/*
* Destroy any in core blocks past the truncation length.
* Called with the underlying vnode locked, which should prevent new dirty
* buffers from being queued.
*/
int
vtruncbuf(struct vnode *vp, daddr_t lbn, bool catch, int slptimeo)
{
struct buf *bp, *nbp;
int error;
voff_t off;
off = round_page((voff_t)lbn << vp->v_mount->mnt_fs_bshift);
mutex_enter(&vp->v_interlock);
error = VOP_PUTPAGES(vp, off, 0, PGO_FREE | PGO_SYNCIO);
if (error) {
return error;
}
mutex_enter(&bufcache_lock);
restart:
for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
if (bp->b_lblkno < lbn)
continue;
error = bbusy(bp, catch, slptimeo, NULL);
if (error != 0) {
if (error == EPASSTHROUGH)
goto restart;
mutex_exit(&bufcache_lock);
return (error);
}
brelsel(bp, BC_INVAL | BC_VFLUSH);
}
for (bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
if (bp->b_lblkno < lbn)
continue;
error = bbusy(bp, catch, slptimeo, NULL);
if (error != 0) {
if (error == EPASSTHROUGH)
goto restart;
mutex_exit(&bufcache_lock);
return (error);
}
brelsel(bp, BC_INVAL | BC_VFLUSH);
}
mutex_exit(&bufcache_lock);
return (0);
}
/*
* Flush all dirty buffers from a vnode.
* Called with the underlying vnode locked, which should prevent new dirty
* buffers from being queued.
*/
void
vflushbuf(struct vnode *vp, int sync)
{
struct buf *bp, *nbp;
int flags = PGO_CLEANIT | PGO_ALLPAGES | (sync ? PGO_SYNCIO : 0);
bool dirty;
mutex_enter(&vp->v_interlock);
(void) VOP_PUTPAGES(vp, 0, 0, flags);
loop:
mutex_enter(&bufcache_lock);
for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = LIST_NEXT(bp, b_vnbufs);
if ((bp->b_cflags & BC_BUSY))
continue;
if ((bp->b_oflags & BO_DELWRI) == 0)
panic("vflushbuf: not dirty, bp %p", bp);
bp->b_cflags |= BC_BUSY | BC_VFLUSH;
mutex_exit(&bufcache_lock);
/*
* Wait for I/O associated with indirect blocks to complete,
* since there is no way to quickly wait for them below.
*/
if (bp->b_vp == vp || sync == 0)
(void) bawrite(bp);
else
(void) bwrite(bp);
goto loop;
}
mutex_exit(&bufcache_lock);
if (sync == 0)
return;
mutex_enter(&vp->v_interlock);
while (vp->v_numoutput != 0)
cv_wait(&vp->v_cv, &vp->v_interlock);
dirty = !LIST_EMPTY(&vp->v_dirtyblkhd);
mutex_exit(&vp->v_interlock);
if (dirty) {
vprint("vflushbuf: dirty", vp);
goto loop;
}
}
/*
* Associate a buffer with a vnode. There must already be a hold on
* the vnode.
*/
void
bgetvp(struct vnode *vp, struct buf *bp)
{
KASSERT(bp->b_vp == NULL);
KASSERT(bp->b_objlock == &buffer_lock);
KASSERT(mutex_owned(&vp->v_interlock));
KASSERT(mutex_owned(&bufcache_lock));
KASSERT((bp->b_cflags & BC_BUSY) != 0);
vholdl(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);
bp->b_objlock = &vp->v_interlock;
}
/*
* Disassociate a buffer from a vnode.
*/
void
brelvp(struct buf *bp)
{
struct vnode *vp = bp->b_vp;
KASSERT(vp != NULL);
KASSERT(bp->b_objlock == &vp->v_interlock);
KASSERT(mutex_owned(&vp->v_interlock));
KASSERT(mutex_owned(&bufcache_lock));
KASSERT((bp->b_cflags & BC_BUSY) != 0);
/*
* Delete from old vnode list, if on one.
*/
if (LIST_NEXT(bp, b_vnbufs) != NOLIST)
bufremvn(bp);
if (TAILQ_EMPTY(&vp->v_uobj.memq) && (vp->v_iflag & VI_ONWORKLST) &&
LIST_FIRST(&vp->v_dirtyblkhd) == NULL) {
vp->v_iflag &= ~VI_WRMAPDIRTY;
vn_syncer_remove_from_worklist(vp);
}
bp->b_objlock = &buffer_lock;
bp->b_vp = NULL;
holdrelel(vp);
}
/*
* Reassign a buffer from one vnode list to another.
* The list reassignment must be within the same vnode.
* Used to assign file specific control information
* (indirect blocks) to the list to which they belong.
*/
void
reassignbuf(struct buf *bp, struct vnode *vp)
{
struct buflists *listheadp;
int delayx;
KASSERT(mutex_owned(&bufcache_lock));
KASSERT(bp->b_objlock == &vp->v_interlock);
KASSERT(mutex_owned(&vp->v_interlock));
KASSERT((bp->b_cflags & BC_BUSY) != 0);
/*
* Delete from old vnode list, if on one.
*/
if (LIST_NEXT(bp, b_vnbufs) != NOLIST)
bufremvn(bp);
/*
* If dirty, put on list of dirty buffers;
* otherwise insert onto list of clean buffers.
*/
if ((bp->b_oflags & BO_DELWRI) == 0) {
listheadp = &vp->v_cleanblkhd;
if (TAILQ_EMPTY(&vp->v_uobj.memq) &&
(vp->v_iflag & VI_ONWORKLST) &&
LIST_FIRST(&vp->v_dirtyblkhd) == NULL) {
vp->v_iflag &= ~VI_WRMAPDIRTY;
vn_syncer_remove_from_worklist(vp);
}
} else {
listheadp = &vp->v_dirtyblkhd;
if ((vp->v_iflag & VI_ONWORKLST) == 0) {
switch (vp->v_type) {
case VDIR:
delayx = dirdelay;
break;
case VBLK:
if (vp->v_specmountpoint != NULL) {
delayx = metadelay;
break;
}
/* fall through */
default:
delayx = filedelay;
break;
}
if (!vp->v_mount ||
(vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
vn_syncer_add_to_worklist(vp, delayx);
}
}
bufinsvn(bp, listheadp);
}
/*
* Get a new unique fsid
*/
void
vfs_getnewfsid(struct mount *mp)
{
static u_short xxxfs_mntid;
fsid_t tfsid;
int mtype;
mutex_enter(&mntid_lock);
mtype = makefstype(mp->mnt_op->vfs_name);
mp->mnt_stat.f_fsidx.__fsid_val[0] = makedev(mtype, 0);
mp->mnt_stat.f_fsidx.__fsid_val[1] = mtype;
mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
if (xxxfs_mntid == 0)
++xxxfs_mntid;
tfsid.__fsid_val[0] = makedev(mtype & 0xff, xxxfs_mntid);
tfsid.__fsid_val[1] = mtype;
if (!CIRCLEQ_EMPTY(&mountlist)) {
while (vfs_getvfs(&tfsid)) {
tfsid.__fsid_val[0]++;
xxxfs_mntid++;
}
}
mp->mnt_stat.f_fsidx.__fsid_val[0] = tfsid.__fsid_val[0];
mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
mutex_exit(&mntid_lock);
}
/*
* Make a 'unique' number from a mount type name.
*/
long
makefstype(const char *type)
{
long rv;
for (rv = 0; *type; type++) {
rv <<= 2;
rv ^= *type;
}
return rv;
}
/*
* Set vnode attributes to VNOVAL
*/
void
vattr_null(struct vattr *vap)
{
vap->va_type = VNON;
/*
* Assign individually so that it is safe even if size and
* sign of each member are varied.
*/
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_size = VNOVAL;
vap->va_blocksize = VNOVAL;
vap->va_atime.tv_sec =
vap->va_mtime.tv_sec =
vap->va_ctime.tv_sec =
vap->va_birthtime.tv_sec = VNOVAL;
vap->va_atime.tv_nsec =
vap->va_mtime.tv_nsec =
vap->va_ctime.tv_nsec =
vap->va_birthtime.tv_nsec = VNOVAL;
vap->va_gen = VNOVAL;
vap->va_flags = VNOVAL;
vap->va_rdev = VNOVAL;
vap->va_bytes = VNOVAL;
vap->va_vaflags = 0;
}
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
#define ARRAY_PRINT(idx, arr) \
((idx) > 0 && (idx) < ARRAY_SIZE(arr) ? (arr)[(idx)] : "UNKNOWN")
const char * const vnode_tags[] = { VNODE_TAGS };
const char * const vnode_types[] = { VNODE_TYPES };
const char vnode_flagbits[] = VNODE_FLAGBITS;
/*
* Print out a description of a vnode.
*/
void
vprint(const char *label, struct vnode *vp)
{
struct vnlock *vl;
char bf[96];
int flag;
vl = (vp->v_vnlock != NULL ? vp->v_vnlock : &vp->v_lock);
flag = vp->v_iflag | vp->v_vflag | vp->v_uflag;
bitmask_snprintf(flag, vnode_flagbits, bf, sizeof(bf));
if (label != NULL)
printf("%s: ", label);
printf("vnode @ %p, flags (%s)\n\ttag %s(%d), type %s(%d), "
"usecount %d, writecount %d, holdcount %d\n"
"\tfreelisthd %p, mount %p, data %p lock %p recursecnt %d\n",
vp, bf, ARRAY_PRINT(vp->v_tag, vnode_tags), vp->v_tag,
ARRAY_PRINT(vp->v_type, vnode_types), vp->v_type,
vp->v_usecount, vp->v_writecount, vp->v_holdcnt,
vp->v_freelisthd, vp->v_mount, vp->v_data, vl, vl->vl_recursecnt);
if (vp->v_data != NULL) {
printf("\t");
VOP_PRINT(vp);
}
}
#ifdef DEBUG
/*
* List all of the locked vnodes in the system.
* Called when debugging the kernel.
*/
void
printlockedvnodes(void)
{
struct mount *mp, *nmp;
struct vnode *vp;
printf("Locked vnodes\n");
mutex_enter(&mountlist_lock);
for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
mp = nmp) {
if (vfs_busy(mp, &nmp)) {
continue;
}
TAILQ_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (VOP_ISLOCKED(vp))
vprint(NULL, vp);
}
mutex_enter(&mountlist_lock);
vfs_unbusy(mp, false, &nmp);
}
mutex_exit(&mountlist_lock);
}
#endif
/*
* Do the usual access checking.
* file_mode, uid and gid are from the vnode in question,
* while acc_mode and cred are from the VOP_ACCESS parameter list
*/
int
vaccess(enum vtype type, mode_t file_mode, uid_t uid, gid_t gid,
mode_t acc_mode, kauth_cred_t cred)
{
mode_t mask;
int error, ismember;
/*
* Super-user always gets read/write access, but execute access depends
* on at least one execute bit being set.
*/
if (kauth_authorize_generic(cred, KAUTH_GENERIC_ISSUSER, NULL) == 0) {
if ((acc_mode & VEXEC) && type != VDIR &&
(file_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0)
return (EACCES);
return (0);
}
mask = 0;
/* Otherwise, check the owner. */
if (kauth_cred_geteuid(cred) == uid) {
if (acc_mode & VEXEC)
mask |= S_IXUSR;
if (acc_mode & VREAD)
mask |= S_IRUSR;
if (acc_mode & VWRITE)
mask |= S_IWUSR;
return ((file_mode & mask) == mask ? 0 : EACCES);
}
/* Otherwise, check the groups. */
error = kauth_cred_ismember_gid(cred, gid, &ismember);
if (error)
return (error);
if (kauth_cred_getegid(cred) == gid || ismember) {
if (acc_mode & VEXEC)
mask |= S_IXGRP;
if (acc_mode & VREAD)
mask |= S_IRGRP;
if (acc_mode & VWRITE)
mask |= S_IWGRP;
return ((file_mode & mask) == mask ? 0 : EACCES);
}
/* Otherwise, check everyone else. */
if (acc_mode & VEXEC)
mask |= S_IXOTH;
if (acc_mode & VREAD)
mask |= S_IROTH;
if (acc_mode & VWRITE)
mask |= S_IWOTH;
return ((file_mode & mask) == mask ? 0 : EACCES);
}
/*
* Given a file system name, look up the vfsops for that
* file system, or return NULL if file system isn't present
* in the kernel.
*/
struct vfsops *
vfs_getopsbyname(const char *name)
{
struct vfsops *v;
mutex_enter(&vfs_list_lock);
LIST_FOREACH(v, &vfs_list, vfs_list) {
if (strcmp(v->vfs_name, name) == 0)
break;
}
if (v != NULL)
v->vfs_refcount++;
mutex_exit(&vfs_list_lock);
return (v);
}
void
copy_statvfs_info(struct statvfs *sbp, const struct mount *mp)
{
const struct statvfs *mbp;
if (sbp == (mbp = &mp->mnt_stat))
return;
(void)memcpy(&sbp->f_fsidx, &mbp->f_fsidx, sizeof(sbp->f_fsidx));
sbp->f_fsid = mbp->f_fsid;
sbp->f_owner = mbp->f_owner;
sbp->f_flag = mbp->f_flag;
sbp->f_syncwrites = mbp->f_syncwrites;
sbp->f_asyncwrites = mbp->f_asyncwrites;
sbp->f_syncreads = mbp->f_syncreads;
sbp->f_asyncreads = mbp->f_asyncreads;
(void)memcpy(sbp->f_spare, mbp->f_spare, sizeof(mbp->f_spare));
(void)memcpy(sbp->f_fstypename, mbp->f_fstypename,
sizeof(sbp->f_fstypename));
(void)memcpy(sbp->f_mntonname, mbp->f_mntonname,
sizeof(sbp->f_mntonname));
(void)memcpy(sbp->f_mntfromname, mp->mnt_stat.f_mntfromname,
sizeof(sbp->f_mntfromname));
sbp->f_namemax = mbp->f_namemax;
}
int
set_statvfs_info(const char *onp, int ukon, const char *fromp, int ukfrom,
const char *vfsname, struct mount *mp, struct lwp *l)
{
int error;
size_t size;
struct statvfs *sfs = &mp->mnt_stat;
int (*fun)(const void *, void *, size_t, size_t *);
(void)strlcpy(mp->mnt_stat.f_fstypename, vfsname,
sizeof(mp->mnt_stat.f_fstypename));
if (onp) {
struct cwdinfo *cwdi = l->l_proc->p_cwdi;
fun = (ukon == UIO_SYSSPACE) ? copystr : copyinstr;
if (cwdi->cwdi_rdir != NULL) {
size_t len;
char *bp;
char *path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
if (!path) /* XXX can't happen with M_WAITOK */
return ENOMEM;
bp = path + MAXPATHLEN;
*--bp = '\0';
rw_enter(&cwdi->cwdi_lock, RW_READER);
error = getcwd_common(cwdi->cwdi_rdir, rootvnode, &bp,
path, MAXPATHLEN / 2, 0, l);
rw_exit(&cwdi->cwdi_lock);
if (error) {
free(path, M_TEMP);
return error;
}
len = strlen(bp);
if (len > sizeof(sfs->f_mntonname) - 1)
len = sizeof(sfs->f_mntonname) - 1;
(void)strncpy(sfs->f_mntonname, bp, len);
free(path, M_TEMP);
if (len < sizeof(sfs->f_mntonname) - 1) {
error = (*fun)(onp, &sfs->f_mntonname[len],
sizeof(sfs->f_mntonname) - len - 1, &size);
if (error)
return error;
size += len;
} else {
size = len;
}
} else {
error = (*fun)(onp, &sfs->f_mntonname,
sizeof(sfs->f_mntonname) - 1, &size);
if (error)
return error;
}
(void)memset(sfs->f_mntonname + size, 0,
sizeof(sfs->f_mntonname) - size);
}
if (fromp) {
fun = (ukfrom == UIO_SYSSPACE) ? copystr : copyinstr;
error = (*fun)(fromp, sfs->f_mntfromname,
sizeof(sfs->f_mntfromname) - 1, &size);
if (error)
return error;
(void)memset(sfs->f_mntfromname + size, 0,
sizeof(sfs->f_mntfromname) - size);
}
return 0;
}
void
vfs_timestamp(struct timespec *ts)
{
nanotime(ts);
}
time_t rootfstime; /* recorded root fs time, if known */
void
setrootfstime(time_t t)
{
rootfstime = t;
}
/*
* mount_specific_key_create --
* Create a key for subsystem mount-specific data.
*/
int
mount_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor)
{
return (specificdata_key_create(mount_specificdata_domain, keyp, dtor));
}
/*
* mount_specific_key_delete --
* Delete a key for subsystem mount-specific data.
*/
void
mount_specific_key_delete(specificdata_key_t key)
{
specificdata_key_delete(mount_specificdata_domain, key);
}
/*
* mount_initspecific --
* Initialize a mount's specificdata container.
*/
void
mount_initspecific(struct mount *mp)
{
int error;
error = specificdata_init(mount_specificdata_domain,
&mp->mnt_specdataref);
KASSERT(error == 0);
}
/*
* mount_finispecific --
* Finalize a mount's specificdata container.
*/
void
mount_finispecific(struct mount *mp)
{
specificdata_fini(mount_specificdata_domain, &mp->mnt_specdataref);
}
/*
* mount_getspecific --
* Return mount-specific data corresponding to the specified key.
*/
void *
mount_getspecific(struct mount *mp, specificdata_key_t key)
{
return (specificdata_getspecific(mount_specificdata_domain,
&mp->mnt_specdataref, key));
}
/*
* mount_setspecific --
* Set mount-specific data corresponding to the specified key.
*/
void
mount_setspecific(struct mount *mp, specificdata_key_t key, void *data)
{
specificdata_setspecific(mount_specificdata_domain,
&mp->mnt_specdataref, key, data);
}
int
VFS_MOUNT(struct mount *mp, const char *a, void *b, size_t *c)
{
int error;
KERNEL_LOCK(1, NULL);
error = (*(mp->mnt_op->vfs_mount))(mp, a, b, c);
KERNEL_UNLOCK_ONE(NULL);
return error;
}
int
VFS_START(struct mount *mp, int a)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_start))(mp, a);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_UNMOUNT(struct mount *mp, int a)
{
int error;
KERNEL_LOCK(1, NULL);
error = (*(mp->mnt_op->vfs_unmount))(mp, a);
KERNEL_UNLOCK_ONE(NULL);
return error;
}
int
VFS_ROOT(struct mount *mp, struct vnode **a)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_root))(mp, a);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_QUOTACTL(struct mount *mp, int a, uid_t b, void *c)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_quotactl))(mp, a, b, c);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_STATVFS(struct mount *mp, struct statvfs *a)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_statvfs))(mp, a);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_SYNC(struct mount *mp, int a, struct kauth_cred *b)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_sync))(mp, a, b);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_FHTOVP(struct mount *mp, struct fid *a, struct vnode **b)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_fhtovp))(mp, a, b);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_VPTOFH(struct vnode *vp, struct fid *a, size_t *b)
{
int error;
if ((vp->v_vflag & VV_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(vp->v_mount->mnt_op->vfs_vptofh))(vp, a, b);
if ((vp->v_vflag & VV_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_SNAPSHOT(struct mount *mp, struct vnode *a, struct timespec *b)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_snapshot))(mp, a, b);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
int
VFS_EXTATTRCTL(struct mount *mp, int a, struct vnode *b, int c, const char *d)
{
int error;
KERNEL_LOCK(1, NULL); /* XXXSMP check ffs */
error = (*(mp->mnt_op->vfs_extattrctl))(mp, a, b, c, d);
KERNEL_UNLOCK_ONE(NULL); /* XXX */
return error;
}
int
VFS_SUSPENDCTL(struct mount *mp, int a)
{
int error;
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_LOCK(1, NULL);
}
error = (*(mp->mnt_op->vfs_suspendctl))(mp, a);
if ((mp->mnt_iflag & IMNT_MPSAFE) == 0) {
KERNEL_UNLOCK_ONE(NULL);
}
return error;
}
#ifdef DDB
static const char buf_flagbits[] = BUF_FLAGBITS;
void
vfs_buf_print(struct buf *bp, int full, void (*pr)(const char *, ...))
{
char bf[1024];
(*pr)(" vp %p lblkno 0x%"PRIx64" blkno 0x%"PRIx64" rawblkno 0x%"
PRIx64 " dev 0x%x\n",
bp->b_vp, bp->b_lblkno, bp->b_blkno, bp->b_rawblkno, bp->b_dev);
bitmask_snprintf(bp->b_flags | bp->b_oflags | bp->b_cflags,
buf_flagbits, bf, sizeof(bf));
(*pr)(" error %d flags 0x%s\n", bp->b_error, bf);
(*pr)(" bufsize 0x%lx bcount 0x%lx resid 0x%lx\n",
bp->b_bufsize, bp->b_bcount, bp->b_resid);
(*pr)(" data %p saveaddr %p dep %p\n",
bp->b_data, bp->b_saveaddr, LIST_FIRST(&bp->b_dep));
(*pr)(" iodone %p objlock %p\n", bp->b_iodone, bp->b_objlock);
}
void
vfs_vnode_print(struct vnode *vp, int full, void (*pr)(const char *, ...))
{
char bf[256];
uvm_object_printit(&vp->v_uobj, full, pr);
bitmask_snprintf(vp->v_iflag | vp->v_vflag | vp->v_uflag,
vnode_flagbits, bf, sizeof(bf));
(*pr)("\nVNODE flags %s\n", bf);
(*pr)("mp %p numoutput %d size 0x%llx writesize 0x%llx\n",
vp->v_mount, vp->v_numoutput, vp->v_size, vp->v_writesize);
(*pr)("data %p writecount %ld holdcnt %ld\n",
vp->v_data, vp->v_writecount, vp->v_holdcnt);
(*pr)("tag %s(%d) type %s(%d) mount %p typedata %p\n",
ARRAY_PRINT(vp->v_tag, vnode_tags), vp->v_tag,
ARRAY_PRINT(vp->v_type, vnode_types), vp->v_type,
vp->v_mount, vp->v_mountedhere);
(*pr)("v_lock %p v_vnlock %p\n", &vp->v_lock, vp->v_vnlock);
if (full) {
struct buf *bp;
(*pr)("clean bufs:\n");
LIST_FOREACH(bp, &vp->v_cleanblkhd, b_vnbufs) {
(*pr)(" bp %p\n", bp);
vfs_buf_print(bp, full, pr);
}
(*pr)("dirty bufs:\n");
LIST_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs) {
(*pr)(" bp %p\n", bp);
vfs_buf_print(bp, full, pr);
}
}
}
void
vfs_mount_print(struct mount *mp, int full, void (*pr)(const char *, ...))
{
char sbuf[256];
(*pr)("vnodecovered = %p syncer = %p data = %p\n",
mp->mnt_vnodecovered,mp->mnt_syncer,mp->mnt_data);
(*pr)("fs_bshift %d dev_bshift = %d\n",
mp->mnt_fs_bshift,mp->mnt_dev_bshift);
bitmask_snprintf(mp->mnt_flag, __MNT_FLAG_BITS, sbuf, sizeof(sbuf));
(*pr)("flag = %s\n", sbuf);
bitmask_snprintf(mp->mnt_iflag, __IMNT_FLAG_BITS, sbuf, sizeof(sbuf));
(*pr)("iflag = %s\n", sbuf);
(*pr)("refcnt = %d unmounting @ %p updating @ %p\n", mp->mnt_refcnt,
&mp->mnt_unmounting, &mp->mnt_updating);
(*pr)("statvfs cache:\n");
(*pr)("\tbsize = %lu\n",mp->mnt_stat.f_bsize);
(*pr)("\tfrsize = %lu\n",mp->mnt_stat.f_frsize);
(*pr)("\tiosize = %lu\n",mp->mnt_stat.f_iosize);
(*pr)("\tblocks = %"PRIu64"\n",mp->mnt_stat.f_blocks);
(*pr)("\tbfree = %"PRIu64"\n",mp->mnt_stat.f_bfree);
(*pr)("\tbavail = %"PRIu64"\n",mp->mnt_stat.f_bavail);
(*pr)("\tbresvd = %"PRIu64"\n",mp->mnt_stat.f_bresvd);
(*pr)("\tfiles = %"PRIu64"\n",mp->mnt_stat.f_files);
(*pr)("\tffree = %"PRIu64"\n",mp->mnt_stat.f_ffree);
(*pr)("\tfavail = %"PRIu64"\n",mp->mnt_stat.f_favail);
(*pr)("\tfresvd = %"PRIu64"\n",mp->mnt_stat.f_fresvd);
(*pr)("\tf_fsidx = { 0x%"PRIx32", 0x%"PRIx32" }\n",
mp->mnt_stat.f_fsidx.__fsid_val[0],
mp->mnt_stat.f_fsidx.__fsid_val[1]);
(*pr)("\towner = %"PRIu32"\n",mp->mnt_stat.f_owner);
(*pr)("\tnamemax = %lu\n",mp->mnt_stat.f_namemax);
bitmask_snprintf(mp->mnt_stat.f_flag, __MNT_FLAG_BITS, sbuf,
sizeof(sbuf));
(*pr)("\tflag = %s\n",sbuf);
(*pr)("\tsyncwrites = %" PRIu64 "\n",mp->mnt_stat.f_syncwrites);
(*pr)("\tasyncwrites = %" PRIu64 "\n",mp->mnt_stat.f_asyncwrites);
(*pr)("\tsyncreads = %" PRIu64 "\n",mp->mnt_stat.f_syncreads);
(*pr)("\tasyncreads = %" PRIu64 "\n",mp->mnt_stat.f_asyncreads);
(*pr)("\tfstypename = %s\n",mp->mnt_stat.f_fstypename);
(*pr)("\tmntonname = %s\n",mp->mnt_stat.f_mntonname);
(*pr)("\tmntfromname = %s\n",mp->mnt_stat.f_mntfromname);
{
int cnt = 0;
struct vnode *vp;
(*pr)("locked vnodes =");
TAILQ_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (VOP_ISLOCKED(vp)) {
if ((++cnt % 6) == 0) {
(*pr)(" %p,\n\t", vp);
} else {
(*pr)(" %p,", vp);
}
}
}
(*pr)("\n");
}
if (full) {
int cnt = 0;
struct vnode *vp;
(*pr)("all vnodes =");
TAILQ_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) {
if (!TAILQ_NEXT(vp, v_mntvnodes)) {
(*pr)(" %p", vp);
} else if ((++cnt % 6) == 0) {
(*pr)(" %p,\n\t", vp);
} else {
(*pr)(" %p,", vp);
}
}
(*pr)("\n", vp);
}
}
#endif /* DDB */
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