freebsd-skq/sys/ufs/lfs/lfs_inode.c
Bruce Evans 3c81694426 Fixed some invalid (non-atomic) accesses to `time', mostly ones of the
form `tv = time'.  Use a new function gettime().  The current version
just forces atomicicity without fixing precision or efficiency bugs.
Simplified some related valid accesses by using the central function.
1997-03-22 06:53:45 +00:00

381 lines
11 KiB
C

/*
* Copyright (c) 1986, 1989, 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. 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.
*
* @(#)lfs_inode.c 8.5 (Berkeley) 12/30/93
* $Id: lfs_inode.c,v 1.15 1997/02/22 09:47:21 peter Exp $
*/
#include "opt_quota.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_extern.h>
#include <ufs/ufs/quota.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>
int
lfs_init()
{
return (ufs_init());
}
/* Search a block for a specific dinode. */
struct dinode *
lfs_ifind(fs, ino, dip)
struct lfs *fs;
ino_t ino;
register struct dinode *dip;
{
register int cnt;
register struct dinode *ldip;
for (cnt = INOPB(fs), ldip = dip + (cnt - 1); cnt--; --ldip)
if (ldip->di_inumber == ino)
return (ldip);
panic("lfs_ifind: dinode %u not found", ino);
/* NOTREACHED */
}
int
lfs_update(ap)
struct vop_update_args /* {
struct vnode *a_vp;
struct timeval *a_access;
struct timeval *a_modify;
int a_waitfor;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct inode *ip;
int error;
if (vp->v_mount->mnt_flag & MNT_RDONLY){
return (0);
}
ip = VTOI(vp);
/* XXX
* We used to just return here. Now we make sure to check if
* we were called by lfs_fsync, since in this case, the inode
* may have been written to disk without all buffers connected
* with the vnode being flushed. It seems really suspicious
* that this could happen since from what I understand of the
* intended semantics, one of these flags should be set if there
* are still dirty buffers. Compare to how ffs_fsync/ffs_update
* work together and you'll see what I mean.
*/
if (((ip->i_flag & (IN_ACCESS|IN_CHANGE|IN_MODIFIED|IN_UPDATE)) == 0)
&& (vp->v_dirtyblkhd.lh_first == NULL))
return(0);
if (ip->i_flag & IN_ACCESS)
ip->i_atime.tv_sec = ap->a_access->tv_sec;
if (ip->i_flag & IN_UPDATE) {
ip->i_mtime.tv_sec = ap->a_modify->tv_sec;
(ip)->i_modrev++;
}
if (ip->i_flag & IN_CHANGE)
ip->i_ctime.tv_sec = time.tv_sec;
ip->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE);
if (!(ip->i_flag & IN_MODIFIED))
++(VFSTOUFS(vp->v_mount)->um_lfs->lfs_uinodes);
ip->i_flag |= IN_MODIFIED;
/* If sync, push back the vnode and any dirty blocks it may have. */
error = (ap->a_waitfor & LFS_SYNC ? lfs_vflush(vp) : 0);
if(ap->a_waitfor & LFS_SYNC && vp->v_dirtyblkhd.lh_first != NULL)
panic("lfs_update: dirty bufs");
return( error );
}
/* Update segment usage information when removing a block. */
#define UPDATE_SEGUSE \
if (lastseg != -1) { \
LFS_SEGENTRY(sup, fs, lastseg, sup_bp); \
if ((num << fs->lfs_bshift) > sup->su_nbytes) \
panic("lfs_truncate: negative bytes in segment %d", \
lastseg); \
sup->su_nbytes -= num << fs->lfs_bshift; \
e1 = VOP_BWRITE(sup_bp); \
blocksreleased += num; \
}
#define SEGDEC { \
if (daddr != 0) { \
if (lastseg != (seg = datosn(fs, daddr))) { \
UPDATE_SEGUSE; \
num = 1; \
lastseg = seg; \
} else \
++num; \
} \
}
/*
* Truncate the inode ip to at most length size. Update segment usage
* table information.
*/
/* ARGSUSED */
int
lfs_truncate(ap)
struct vop_truncate_args /* {
struct vnode *a_vp;
off_t a_length;
int a_flags;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
register struct indir *inp;
register int i;
register daddr_t *daddrp;
register struct vnode *vp = ap->a_vp;
off_t length = ap->a_length;
struct buf *bp, *sup_bp;
struct timeval tv;
struct ifile *ifp;
struct inode *ip;
struct lfs *fs;
struct indir a[NIADDR + 2], a_end[NIADDR + 2];
SEGUSE *sup;
daddr_t daddr, lastblock, lbn, olastblock;
long off, a_released, blocksreleased, i_released;
int e1, e2, depth, lastseg, num, offset, seg, size;
ip = VTOI(vp);
gettime(&tv);
if (vp->v_type == VLNK && vp->v_mount->mnt_maxsymlinklen > 0) {
#ifdef DIAGNOSTIC
if (length != 0)
panic("lfs_truncate: partial truncate of symlink");
#endif
bzero((char *)&ip->i_shortlink, (u_int)ip->i_size);
ip->i_size = 0;
ip->i_flag |= IN_CHANGE | IN_UPDATE;
return (VOP_UPDATE(vp, &tv, &tv, 0));
}
vnode_pager_setsize(vp, (u_long)length);
fs = ip->i_lfs;
/* If length is larger than the file, just update the times. */
if (ip->i_size <= length) {
ip->i_flag |= IN_CHANGE | IN_UPDATE;
return (VOP_UPDATE(vp, &tv, &tv, 0));
}
/*
* Calculate index into inode's block list of last direct and indirect
* blocks (if any) which we want to keep. Lastblock is 0 when the
* file is truncated to 0.
*/
lastblock = lblkno(fs, length + fs->lfs_bsize - 1);
olastblock = lblkno(fs, ip->i_size + fs->lfs_bsize - 1) - 1;
/*
* Update the size of the file. If the file is not being truncated to
* a block boundry, the contents of the partial block following the end
* of the file must be zero'ed in case it ever become accessable again
* because of subsequent file growth.
*/
offset = blkoff(fs, length);
if (offset == 0)
ip->i_size = length;
else {
lbn = lblkno(fs, length);
#ifdef QUOTA
if (e1 = getinoquota(ip))
return (e1);
#endif
if (e1 = bread(vp, lbn, fs->lfs_bsize, NOCRED, &bp))
return (e1);
ip->i_size = length;
size = blksize(fs);
bzero((char *)bp->b_data + offset, (u_int)(size - offset));
allocbuf(bp, size);
if (e1 = VOP_BWRITE(bp))
return (e1);
}
/*
* Modify sup->su_nbyte counters for each deleted block; keep track
* of number of blocks removed for ip->i_blocks.
*/
blocksreleased = 0;
num = 0;
lastseg = -1;
for (lbn = olastblock; lbn >= lastblock;) {
/* XXX use run length from bmap array to make this faster */
ufs_bmaparray(vp, lbn, &daddr, a, &depth, NULL, NULL);
if (lbn == olastblock)
for (i = NIADDR + 2; i--;)
a_end[i] = a[i];
switch (depth) {
case 0: /* Direct block. */
daddr = ip->i_db[lbn];
SEGDEC;
ip->i_db[lbn] = 0;
--lbn;
break;
#ifdef DIAGNOSTIC
case 1: /* An indirect block. */
panic("lfs_truncate: ufs_bmaparray returned depth 1");
/* NOTREACHED */
#endif
default: /* Chain of indirect blocks. */
inp = a + --depth;
if (inp->in_off > 0 && lbn != lastblock) {
lbn -= inp->in_off < lbn - lastblock ?
inp->in_off : lbn - lastblock;
break;
}
for (; depth && (inp->in_off == 0 || lbn == lastblock);
--inp, --depth) {
if (bread(vp,
inp->in_lbn, fs->lfs_bsize, NOCRED, &bp))
panic("lfs_truncate: bread bno %d",
inp->in_lbn);
daddrp = (daddr_t *)bp->b_data + inp->in_off;
for (i = inp->in_off;
i++ <= a_end[depth].in_off;) {
daddr = *daddrp++;
SEGDEC;
}
a_end[depth].in_off = NINDIR(fs) - 1;
if (inp->in_off == 0)
brelse (bp);
else {
bzero((daddr_t *)bp->b_data +
inp->in_off, fs->lfs_bsize -
inp->in_off * sizeof(daddr_t));
if (e1 = VOP_BWRITE(bp))
return (e1);
}
}
if (depth == 0 && a[1].in_off == 0) {
off = a[0].in_off;
daddr = ip->i_ib[off];
SEGDEC;
ip->i_ib[off] = 0;
}
if (lbn == lastblock || lbn <= NDADDR)
--lbn;
else {
lbn -= NINDIR(fs);
if (lbn < lastblock)
lbn = lastblock;
}
}
}
UPDATE_SEGUSE;
/* If truncating the file to 0, update the version number. */
if (length == 0) {
LFS_IENTRY(ifp, fs, ip->i_number, bp);
++ifp->if_version;
(void) VOP_BWRITE(bp);
}
#ifdef DIAGNOSTIC
if (ip->i_blocks < fsbtodb(fs, blocksreleased)) {
printf("lfs_truncate: block count < 0\n");
blocksreleased = ip->i_blocks;
}
#endif
ip->i_blocks -= fsbtodb(fs, blocksreleased);
fs->lfs_bfree += fsbtodb(fs, blocksreleased);
ip->i_flag |= IN_CHANGE | IN_UPDATE;
/*
* Traverse dirty block list counting number of dirty buffers
* that are being deleted out of the cache, so that the lfs_avail
* field can be updated.
*/
a_released = 0;
i_released = 0;
for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = bp->b_vnbufs.le_next)
if (bp->b_flags & B_LOCKED) {
++a_released;
/*
* XXX
* When buffers are created in the cache, their block
* number is set equal to their logical block number.
* If that is still true, we are assuming that the
* blocks are new (not yet on disk) and weren't
* counted above. However, there is a slight chance
* that a block's disk address is equal to its logical
* block number in which case, we'll get an overcounting
* here.
*/
if (bp->b_blkno == bp->b_lblkno)
++i_released;
}
blocksreleased = fsbtodb(fs, i_released);
#ifdef DIAGNOSTIC
if (blocksreleased > ip->i_blocks) {
printf("lfs_inode: Warning! %s\n",
"more blocks released from inode than are in inode");
blocksreleased = ip->i_blocks;
}
#endif
fs->lfs_bfree += blocksreleased;
ip->i_blocks -= blocksreleased;
#ifdef DIAGNOSTIC
if (length == 0 && ip->i_blocks != 0)
printf("lfs_inode: Warning! %s%ld%s\n",
"Truncation to zero, but ", ip->i_blocks,
" blocks left on inode");
#endif
fs->lfs_avail += fsbtodb(fs, a_released);
e1 = vinvalbuf(vp, (length > 0) ? V_SAVE : 0, ap->a_cred, ap->a_p,
0, 0);
e2 = VOP_UPDATE(vp, &tv, &tv, 0);
return (e1 ? e1 : e2 ? e2 : 0);
}