NetBSD-5.0.2/sys/ufs/lfs/lfs_bio.c
/* $NetBSD: lfs_bio.c,v 1.114 2008/05/06 18:43:45 ad Exp $ */
/*-
* Copyright (c) 1999, 2000, 2001, 2002, 2003, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Konrad E. Schroder <perseant@hhhh.org>.
*
* 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) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 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.
*
* @(#)lfs_bio.c 8.10 (Berkeley) 6/10/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: lfs_bio.c,v 1.114 2008/05/06 18:43:45 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/resourcevar.h>
#include <sys/mount.h>
#include <sys/kernel.h>
#include <sys/kauth.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>
#include <ufs/lfs/lfs.h>
#include <ufs/lfs/lfs_extern.h>
#include <uvm/uvm.h>
/*
* LFS block write function.
*
* XXX
* No write cost accounting is done.
* This is almost certainly wrong for synchronous operations and NFS.
*
* protected by lfs_lock.
*/
int locked_queue_count = 0; /* Count of locked-down buffers. */
long locked_queue_bytes = 0L; /* Total size of locked buffers. */
int lfs_subsys_pages = 0L; /* Total number LFS-written pages */
int lfs_fs_pagetrip = 0; /* # of pages to trip per-fs write */
int lfs_writing = 0; /* Set if already kicked off a writer
because of buffer space */
/* Lock and condition variables for above. */
kcondvar_t locked_queue_cv;
kcondvar_t lfs_writing_cv;
kmutex_t lfs_lock;
extern int lfs_dostats;
/*
* reserved number/bytes of locked buffers
*/
int locked_queue_rcount = 0;
long locked_queue_rbytes = 0L;
int lfs_fits_buf(struct lfs *, int, int);
int lfs_reservebuf(struct lfs *, struct vnode *vp, struct vnode *vp2,
int, int);
int lfs_reserveavail(struct lfs *, struct vnode *vp, struct vnode *vp2, int);
int
lfs_fits_buf(struct lfs *fs, int n, int bytes)
{
int count_fit, bytes_fit;
ASSERT_NO_SEGLOCK(fs);
KASSERT(mutex_owned(&lfs_lock));
count_fit =
(locked_queue_count + locked_queue_rcount + n < LFS_WAIT_BUFS);
bytes_fit =
(locked_queue_bytes + locked_queue_rbytes + bytes < LFS_WAIT_BYTES);
#ifdef DEBUG
if (!count_fit) {
DLOG((DLOG_AVAIL, "lfs_fits_buf: no fit count: %d + %d + %d >= %d\n",
locked_queue_count, locked_queue_rcount,
n, LFS_WAIT_BUFS));
}
if (!bytes_fit) {
DLOG((DLOG_AVAIL, "lfs_fits_buf: no fit bytes: %ld + %ld + %d >= %ld\n",
locked_queue_bytes, locked_queue_rbytes,
bytes, LFS_WAIT_BYTES));
}
#endif /* DEBUG */
return (count_fit && bytes_fit);
}
/* ARGSUSED */
int
lfs_reservebuf(struct lfs *fs, struct vnode *vp,
struct vnode *vp2, int n, int bytes)
{
ASSERT_MAYBE_SEGLOCK(fs);
KASSERT(locked_queue_rcount >= 0);
KASSERT(locked_queue_rbytes >= 0);
mutex_enter(&lfs_lock);
while (n > 0 && !lfs_fits_buf(fs, n, bytes)) {
int error;
lfs_flush(fs, 0, 0);
error = cv_timedwait_sig(&locked_queue_cv, &lfs_lock,
hz * LFS_BUFWAIT);
if (error && error != EWOULDBLOCK) {
mutex_exit(&lfs_lock);
return error;
}
}
locked_queue_rcount += n;
locked_queue_rbytes += bytes;
mutex_exit(&lfs_lock);
KASSERT(locked_queue_rcount >= 0);
KASSERT(locked_queue_rbytes >= 0);
return 0;
}
/*
* Try to reserve some blocks, prior to performing a sensitive operation that
* requires the vnode lock to be honored. If there is not enough space, give
* up the vnode lock temporarily and wait for the space to become available.
*
* Called with vp locked. (Note nowever that if fsb < 0, vp is ignored.)
*
* XXX YAMT - it isn't safe to unlock vp here
* because the node might be modified while we sleep.
* (eg. cached states like i_offset might be stale,
* the vnode might be truncated, etc..)
* maybe we should have a way to restart the vnodeop (EVOPRESTART?)
* or rearrange vnodeop interface to leave vnode locking to file system
* specific code so that each file systems can have their own vnode locking and
* vnode re-using strategies.
*/
int
lfs_reserveavail(struct lfs *fs, struct vnode *vp,
struct vnode *vp2, int fsb)
{
CLEANERINFO *cip;
struct buf *bp;
int error, slept;
ASSERT_MAYBE_SEGLOCK(fs);
slept = 0;
mutex_enter(&lfs_lock);
while (fsb > 0 && !lfs_fits(fs, fsb + fs->lfs_ravail + fs->lfs_favail)) {
mutex_exit(&lfs_lock);
#if 0
/*
* XXX ideally, we should unlock vnodes here
* because we might sleep very long time.
*/
VOP_UNLOCK(vp, 0);
if (vp2 != NULL) {
VOP_UNLOCK(vp2, 0);
}
#else
/*
* XXX since we'll sleep for cleaner with vnode lock holding,
* deadlock will occur if cleaner tries to lock the vnode.
* (eg. lfs_markv -> lfs_fastvget -> getnewvnode -> vclean)
*/
#endif
if (!slept) {
DLOG((DLOG_AVAIL, "lfs_reserve: waiting for %ld (bfree = %d,"
" est_bfree = %d)\n",
fsb + fs->lfs_ravail + fs->lfs_favail,
fs->lfs_bfree, LFS_EST_BFREE(fs)));
}
++slept;
/* Wake up the cleaner */
LFS_CLEANERINFO(cip, fs, bp);
LFS_SYNC_CLEANERINFO(cip, fs, bp, 0);
lfs_wakeup_cleaner(fs);
mutex_enter(&lfs_lock);
/* Cleaner might have run while we were reading, check again */
if (lfs_fits(fs, fsb + fs->lfs_ravail + fs->lfs_favail))
break;
error = mtsleep(&fs->lfs_avail, PCATCH | PUSER, "lfs_reserve",
0, &lfs_lock);
#if 0
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX use lockstatus */
vn_lock(vp2, LK_EXCLUSIVE | LK_RETRY); /* XXX use lockstatus */
#endif
if (error) {
mutex_exit(&lfs_lock);
return error;
}
}
#ifdef DEBUG
if (slept) {
DLOG((DLOG_AVAIL, "lfs_reserve: woke up\n"));
}
#endif
fs->lfs_ravail += fsb;
mutex_exit(&lfs_lock);
return 0;
}
#ifdef DIAGNOSTIC
int lfs_rescount;
int lfs_rescountdirop;
#endif
int
lfs_reserve(struct lfs *fs, struct vnode *vp, struct vnode *vp2, int fsb)
{
int error;
int cantwait;
ASSERT_MAYBE_SEGLOCK(fs);
if (vp2) {
/* Make sure we're not in the process of reclaiming vp2 */
mutex_enter(&lfs_lock);
while(fs->lfs_flags & LFS_UNDIROP) {
mtsleep(&fs->lfs_flags, PRIBIO + 1, "lfsrundirop", 0,
&lfs_lock);
}
mutex_exit(&lfs_lock);
}
KASSERT(fsb < 0 || VOP_ISLOCKED(vp));
KASSERT(vp2 == NULL || fsb < 0 || VOP_ISLOCKED(vp2));
KASSERT(vp2 == NULL || !(VTOI(vp2)->i_flag & IN_ADIROP));
KASSERT(vp2 == NULL || vp2 != fs->lfs_unlockvp);
cantwait = (VTOI(vp)->i_flag & IN_ADIROP) || fs->lfs_unlockvp == vp;
#ifdef DIAGNOSTIC
if (cantwait) {
if (fsb > 0)
lfs_rescountdirop++;
else if (fsb < 0)
lfs_rescountdirop--;
if (lfs_rescountdirop < 0)
panic("lfs_rescountdirop");
}
else {
if (fsb > 0)
lfs_rescount++;
else if (fsb < 0)
lfs_rescount--;
if (lfs_rescount < 0)
panic("lfs_rescount");
}
#endif
if (cantwait)
return 0;
/*
* XXX
* vref vnodes here so that cleaner doesn't try to reuse them.
* (see XXX comment in lfs_reserveavail)
*/
mutex_enter(&vp->v_interlock);
lfs_vref(vp);
if (vp2 != NULL) {
mutex_enter(&vp2->v_interlock);
lfs_vref(vp2);
}
error = lfs_reserveavail(fs, vp, vp2, fsb);
if (error)
goto done;
/*
* XXX just a guess. should be more precise.
*/
error = lfs_reservebuf(fs, vp, vp2,
fragstoblks(fs, fsb), fsbtob(fs, fsb));
if (error)
lfs_reserveavail(fs, vp, vp2, -fsb);
done:
lfs_vunref(vp);
if (vp2 != NULL) {
lfs_vunref(vp2);
}
return error;
}
int
lfs_bwrite(void *v)
{
struct vop_bwrite_args /* {
struct buf *a_bp;
} */ *ap = v;
struct buf *bp = ap->a_bp;
#ifdef DIAGNOSTIC
if (VTOI(bp->b_vp)->i_lfs->lfs_ronly == 0 && (bp->b_flags & B_ASYNC)) {
panic("bawrite LFS buffer");
}
#endif /* DIAGNOSTIC */
return lfs_bwrite_ext(bp, 0);
}
/*
* Determine if there is enough room currently available to write fsb
* blocks. We need enough blocks for the new blocks, the current
* inode blocks (including potentially the ifile inode), a summary block,
* and the segment usage table, plus an ifile block.
*/
int
lfs_fits(struct lfs *fs, int fsb)
{
int needed;
ASSERT_NO_SEGLOCK(fs);
needed = fsb + btofsb(fs, fs->lfs_sumsize) +
((howmany(fs->lfs_uinodes + 1, INOPB(fs)) + fs->lfs_segtabsz +
1) << (fs->lfs_blktodb - fs->lfs_fsbtodb));
if (needed >= fs->lfs_avail) {
#ifdef DEBUG
DLOG((DLOG_AVAIL, "lfs_fits: no fit: fsb = %ld, uinodes = %ld, "
"needed = %ld, avail = %ld\n",
(long)fsb, (long)fs->lfs_uinodes, (long)needed,
(long)fs->lfs_avail));
#endif
return 0;
}
return 1;
}
int
lfs_availwait(struct lfs *fs, int fsb)
{
int error;
CLEANERINFO *cip;
struct buf *cbp;
ASSERT_NO_SEGLOCK(fs);
/* Push cleaner blocks through regardless */
mutex_enter(&lfs_lock);
if (LFS_SEGLOCK_HELD(fs) &&
fs->lfs_sp->seg_flags & (SEGM_CLEAN | SEGM_FORCE_CKP)) {
mutex_exit(&lfs_lock);
return 0;
}
mutex_exit(&lfs_lock);
while (!lfs_fits(fs, fsb)) {
/*
* Out of space, need cleaner to run.
* Update the cleaner info, then wake it up.
* Note the cleanerinfo block is on the ifile
* so it CANT_WAIT.
*/
LFS_CLEANERINFO(cip, fs, cbp);
LFS_SYNC_CLEANERINFO(cip, fs, cbp, 0);
#ifdef DEBUG
DLOG((DLOG_AVAIL, "lfs_availwait: out of available space, "
"waiting on cleaner\n"));
#endif
lfs_wakeup_cleaner(fs);
#ifdef DIAGNOSTIC
if (LFS_SEGLOCK_HELD(fs))
panic("lfs_availwait: deadlock");
#endif
error = tsleep(&fs->lfs_avail, PCATCH | PUSER, "cleaner", 0);
if (error)
return (error);
}
return 0;
}
int
lfs_bwrite_ext(struct buf *bp, int flags)
{
struct lfs *fs;
struct inode *ip;
struct vnode *vp;
int fsb;
vp = bp->b_vp;
fs = VFSTOUFS(vp->v_mount)->um_lfs;
ASSERT_MAYBE_SEGLOCK(fs);
KASSERT(bp->b_cflags & BC_BUSY);
KASSERT(flags & BW_CLEAN || !LFS_IS_MALLOC_BUF(bp));
KASSERT(((bp->b_oflags | bp->b_flags) & (BO_DELWRI|B_LOCKED))
!= BO_DELWRI);
/*
* Don't write *any* blocks if we're mounted read-only, or
* if we are "already unmounted".
*
* In particular the cleaner can't write blocks either.
*/
if (fs->lfs_ronly || (fs->lfs_pflags & LFS_PF_CLEAN)) {
bp->b_oflags &= ~BO_DELWRI;
bp->b_flags |= B_READ;
bp->b_error = 0;
mutex_enter(&bufcache_lock);
LFS_UNLOCK_BUF(bp);
if (LFS_IS_MALLOC_BUF(bp))
bp->b_cflags &= ~BC_BUSY;
else
brelsel(bp, 0);
mutex_exit(&bufcache_lock);
return (fs->lfs_ronly ? EROFS : 0);
}
/*
* Set the delayed write flag and use reassignbuf to move the buffer
* from the clean list to the dirty one.
*
* Set the B_LOCKED flag and unlock the buffer, causing brelse to move
* the buffer onto the LOCKED free list. This is necessary, otherwise
* getnewbuf() would try to reclaim the buffers using bawrite, which
* isn't going to work.
*
* XXX we don't let meta-data writes run out of space because they can
* come from the segment writer. We need to make sure that there is
* enough space reserved so that there's room to write meta-data
* blocks.
*/
if ((bp->b_flags & B_LOCKED) == 0) {
fsb = fragstofsb(fs, numfrags(fs, bp->b_bcount));
ip = VTOI(vp);
mutex_enter(&lfs_lock);
if (flags & BW_CLEAN) {
LFS_SET_UINO(ip, IN_CLEANING);
} else {
LFS_SET_UINO(ip, IN_MODIFIED);
}
mutex_exit(&lfs_lock);
fs->lfs_avail -= fsb;
mutex_enter(&bufcache_lock);
mutex_enter(&vp->v_interlock);
bp->b_oflags = (bp->b_oflags | BO_DELWRI) & ~BO_DONE;
LFS_LOCK_BUF(bp);
bp->b_flags &= ~B_READ;
bp->b_error = 0;
reassignbuf(bp, bp->b_vp);
mutex_exit(&vp->v_interlock);
} else {
mutex_enter(&bufcache_lock);
}
if (bp->b_iodone != NULL)
bp->b_cflags &= ~BC_BUSY;
else
brelsel(bp, 0);
mutex_exit(&bufcache_lock);
return (0);
}
/*
* Called and return with the lfs_lock held.
*/
void
lfs_flush_fs(struct lfs *fs, int flags)
{
ASSERT_NO_SEGLOCK(fs);
KASSERT(mutex_owned(&lfs_lock));
if (fs->lfs_ronly)
return;
if (lfs_dostats)
++lfs_stats.flush_invoked;
mutex_exit(&lfs_lock);
lfs_writer_enter(fs, "fldirop");
lfs_segwrite(fs->lfs_ivnode->v_mount, flags);
lfs_writer_leave(fs);
mutex_enter(&lfs_lock);
fs->lfs_favail = 0; /* XXX */
}
/*
* This routine initiates segment writes when LFS is consuming too many
* resources. Ideally the pageout daemon would be able to direct LFS
* more subtly.
* XXX We have one static count of locked buffers;
* XXX need to think more about the multiple filesystem case.
*
* Called and return with lfs_lock held.
* If fs != NULL, we hold the segment lock for fs.
*/
void
lfs_flush(struct lfs *fs, int flags, int only_onefs)
{
extern u_int64_t locked_fakequeue_count;
struct mount *mp, *nmp;
struct lfs *tfs;
KASSERT(mutex_owned(&lfs_lock));
KDASSERT(fs == NULL || !LFS_SEGLOCK_HELD(fs));
if (lfs_dostats)
++lfs_stats.write_exceeded;
/* XXX should we include SEGM_CKP here? */
if (lfs_writing && !(flags & SEGM_SYNC)) {
DLOG((DLOG_FLUSH, "lfs_flush: not flushing because another flush is active\n"));
return;
}
while (lfs_writing)
cv_wait(&lfs_writing_cv, &lfs_lock);
lfs_writing = 1;
mutex_exit(&lfs_lock);
if (only_onefs) {
KASSERT(fs != NULL);
if (vfs_busy(fs->lfs_ivnode->v_mount, NULL))
goto errout;
mutex_enter(&lfs_lock);
lfs_flush_fs(fs, flags);
mutex_exit(&lfs_lock);
vfs_unbusy(fs->lfs_ivnode->v_mount, false, NULL);
} else {
locked_fakequeue_count = 0;
mutex_enter(&mountlist_lock);
for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
mp = nmp) {
if (vfs_busy(mp, &nmp)) {
DLOG((DLOG_FLUSH, "lfs_flush: fs vfs_busy\n"));
continue;
}
if (strncmp(&mp->mnt_stat.f_fstypename[0], MOUNT_LFS,
sizeof(mp->mnt_stat.f_fstypename)) == 0) {
tfs = VFSTOUFS(mp)->um_lfs;
mutex_enter(&lfs_lock);
lfs_flush_fs(tfs, flags);
mutex_exit(&lfs_lock);
}
vfs_unbusy(mp, false, &nmp);
}
mutex_exit(&mountlist_lock);
}
LFS_DEBUG_COUNTLOCKED("flush");
wakeup(&lfs_subsys_pages);
errout:
mutex_enter(&lfs_lock);
KASSERT(lfs_writing);
lfs_writing = 0;
wakeup(&lfs_writing);
}
#define INOCOUNT(fs) howmany((fs)->lfs_uinodes, INOPB(fs))
#define INOBYTES(fs) ((fs)->lfs_uinodes * sizeof (struct ufs1_dinode))
/*
* make sure that we don't have too many locked buffers.
* flush buffers if needed.
*/
int
lfs_check(struct vnode *vp, daddr_t blkno, int flags)
{
int error;
struct lfs *fs;
struct inode *ip;
extern pid_t lfs_writer_daemon;
error = 0;
ip = VTOI(vp);
/* If out of buffers, wait on writer */
/* XXX KS - if it's the Ifile, we're probably the cleaner! */
if (ip->i_number == LFS_IFILE_INUM)
return 0;
/* If we're being called from inside a dirop, don't sleep */
if (ip->i_flag & IN_ADIROP)
return 0;
fs = ip->i_lfs;
ASSERT_NO_SEGLOCK(fs);
/*
* If we would flush below, but dirops are active, sleep.
* Note that a dirop cannot ever reach this code!
*/
mutex_enter(&lfs_lock);
while (fs->lfs_dirops > 0 &&
(locked_queue_count + INOCOUNT(fs) > LFS_MAX_BUFS ||
locked_queue_bytes + INOBYTES(fs) > LFS_MAX_BYTES ||
lfs_subsys_pages > LFS_MAX_PAGES ||
fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
lfs_dirvcount > LFS_MAX_DIROP || fs->lfs_diropwait > 0))
{
++fs->lfs_diropwait;
mtsleep(&fs->lfs_writer, PRIBIO+1, "bufdirop", 0,
&lfs_lock);
--fs->lfs_diropwait;
}
#ifdef DEBUG
if (locked_queue_count + INOCOUNT(fs) > LFS_MAX_BUFS)
DLOG((DLOG_FLUSH, "lfs_check: lqc = %d, max %d\n",
locked_queue_count + INOCOUNT(fs), LFS_MAX_BUFS));
if (locked_queue_bytes + INOBYTES(fs) > LFS_MAX_BYTES)
DLOG((DLOG_FLUSH, "lfs_check: lqb = %ld, max %ld\n",
locked_queue_bytes + INOBYTES(fs), LFS_MAX_BYTES));
if (lfs_subsys_pages > LFS_MAX_PAGES)
DLOG((DLOG_FLUSH, "lfs_check: lssp = %d, max %d\n",
lfs_subsys_pages, LFS_MAX_PAGES));
if (lfs_fs_pagetrip && fs->lfs_pages > lfs_fs_pagetrip)
DLOG((DLOG_FLUSH, "lfs_check: fssp = %d, trip at %d\n",
fs->lfs_pages, lfs_fs_pagetrip));
if (lfs_dirvcount > LFS_MAX_DIROP)
DLOG((DLOG_FLUSH, "lfs_check: ldvc = %d, max %d\n",
lfs_dirvcount, LFS_MAX_DIROP));
if (fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs))
DLOG((DLOG_FLUSH, "lfs_check: lfdvc = %d, max %d\n",
fs->lfs_dirvcount, LFS_MAX_FSDIROP(fs)));
if (fs->lfs_diropwait > 0)
DLOG((DLOG_FLUSH, "lfs_check: ldvw = %d\n",
fs->lfs_diropwait));
#endif
/* If there are too many pending dirops, we have to flush them. */
if (fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
lfs_dirvcount > LFS_MAX_DIROP || fs->lfs_diropwait > 0) {
flags |= SEGM_CKP;
}
if (locked_queue_count + INOCOUNT(fs) > LFS_MAX_BUFS ||
locked_queue_bytes + INOBYTES(fs) > LFS_MAX_BYTES ||
lfs_subsys_pages > LFS_MAX_PAGES ||
fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
lfs_dirvcount > LFS_MAX_DIROP || fs->lfs_diropwait > 0) {
lfs_flush(fs, flags, 0);
} else if (lfs_fs_pagetrip && fs->lfs_pages > lfs_fs_pagetrip) {
/*
* If we didn't flush the whole thing, some filesystems
* still might want to be flushed.
*/
++fs->lfs_pdflush;
wakeup(&lfs_writer_daemon);
}
while (locked_queue_count + INOCOUNT(fs) > LFS_WAIT_BUFS ||
locked_queue_bytes + INOBYTES(fs) > LFS_WAIT_BYTES ||
lfs_subsys_pages > LFS_WAIT_PAGES ||
fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
lfs_dirvcount > LFS_MAX_DIROP) {
if (lfs_dostats)
++lfs_stats.wait_exceeded;
DLOG((DLOG_AVAIL, "lfs_check: waiting: count=%d, bytes=%ld\n",
locked_queue_count, locked_queue_bytes));
error = cv_timedwait_sig(&locked_queue_cv, &lfs_lock,
hz * LFS_BUFWAIT);
if (error != EWOULDBLOCK)
break;
/*
* lfs_flush might not flush all the buffers, if some of the
* inodes were locked or if most of them were Ifile blocks
* and we weren't asked to checkpoint. Try flushing again
* to keep us from blocking indefinitely.
*/
if (locked_queue_count + INOCOUNT(fs) > LFS_MAX_BUFS ||
locked_queue_bytes + INOBYTES(fs) > LFS_MAX_BYTES) {
lfs_flush(fs, flags | SEGM_CKP, 0);
}
}
mutex_exit(&lfs_lock);
return (error);
}
/*
* Allocate a new buffer header.
*/
struct buf *
lfs_newbuf(struct lfs *fs, struct vnode *vp, daddr_t daddr, size_t size, int type)
{
struct buf *bp;
size_t nbytes;
ASSERT_MAYBE_SEGLOCK(fs);
nbytes = roundup(size, fsbtob(fs, 1));
bp = getiobuf(NULL, true);
if (nbytes) {
bp->b_data = lfs_malloc(fs, nbytes, type);
/* memset(bp->b_data, 0, nbytes); */
}
#ifdef DIAGNOSTIC
if (vp == NULL)
panic("vp is NULL in lfs_newbuf");
if (bp == NULL)
panic("bp is NULL after malloc in lfs_newbuf");
#endif
bp->b_bufsize = size;
bp->b_bcount = size;
bp->b_lblkno = daddr;
bp->b_blkno = daddr;
bp->b_error = 0;
bp->b_resid = 0;
bp->b_iodone = lfs_callback;
bp->b_cflags = BC_BUSY | BC_NOCACHE;
bp->b_private = fs;
mutex_enter(&bufcache_lock);
mutex_enter(&vp->v_interlock);
bgetvp(vp, bp);
mutex_exit(&vp->v_interlock);
mutex_exit(&bufcache_lock);
return (bp);
}
void
lfs_freebuf(struct lfs *fs, struct buf *bp)
{
struct vnode *vp;
if ((vp = bp->b_vp) != NULL) {
mutex_enter(&bufcache_lock);
mutex_enter(&vp->v_interlock);
brelvp(bp);
mutex_exit(&vp->v_interlock);
mutex_exit(&bufcache_lock);
}
if (!(bp->b_cflags & BC_INVAL)) { /* BC_INVAL indicates a "fake" buffer */
lfs_free(fs, bp->b_data, LFS_NB_UNKNOWN);
bp->b_data = NULL;
}
putiobuf(bp);
}
/*
* Count buffers on the "locked" queue, and compare it to a pro-forma count.
* Don't count malloced buffers, since they don't detract from the total.
*/
void
lfs_countlocked(int *count, long *bytes, const char *msg)
{
struct buf *bp;
int n = 0;
long int size = 0L;
mutex_enter(&bufcache_lock);
TAILQ_FOREACH(bp, &bufqueues[BQ_LOCKED].bq_queue, b_freelist) {
KASSERT(bp->b_iodone == NULL);
n++;
size += bp->b_bufsize;
#ifdef DIAGNOSTIC
if (n > nbuf)
panic("lfs_countlocked: this can't happen: more"
" buffers locked than exist");
#endif
}
/*
* Theoretically this function never really does anything.
* Give a warning if we have to fix the accounting.
*/
if (n != *count) {
DLOG((DLOG_LLIST, "lfs_countlocked: %s: adjusted buf count"
" from %d to %d\n", msg, *count, n));
}
if (size != *bytes) {
DLOG((DLOG_LLIST, "lfs_countlocked: %s: adjusted byte count"
" from %ld to %ld\n", msg, *bytes, size));
}
*count = n;
*bytes = size;
mutex_exit(&bufcache_lock);
return;
}
int
lfs_wait_pages(void)
{
int active, inactive;
uvm_estimatepageable(&active, &inactive);
return LFS_WAIT_RESOURCE(active + inactive + uvmexp.free, 1);
}
int
lfs_max_pages(void)
{
int active, inactive;
uvm_estimatepageable(&active, &inactive);
return LFS_MAX_RESOURCE(active + inactive + uvmexp.free, 1);
}