FreeBSD-5.3/sys/gnu/ext2fs/ext2_inode.c
/*
* modified for Lites 1.1
*
* Aug 1995, Godmar Back (gback@cs.utah.edu)
* University of Utah, Department of Computer Science
*/
/*
* Copyright (c) 1982, 1986, 1989, 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.
* 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.
*
* @(#)ffs_inode.c 8.5 (Berkeley) 12/30/93
* $FreeBSD: src/sys/gnu/ext2fs/ext2_inode.c,v 1.47 2004/04/07 20:46:03 imp Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mount.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <gnu/ext2fs/inode.h>
#include <gnu/ext2fs/ext2_mount.h>
#include <gnu/ext2fs/ext2_fs.h>
#include <gnu/ext2fs/ext2_fs_sb.h>
#include <gnu/ext2fs/fs.h>
#include <gnu/ext2fs/ext2_extern.h>
static int ext2_indirtrunc(struct inode *, int32_t, int32_t, int32_t, int,
long *);
/*
* Update the access, modified, and inode change times as specified by the
* IN_ACCESS, IN_UPDATE, and IN_CHANGE flags respectively. Write the inode
* to disk if the IN_MODIFIED flag is set (it may be set initially, or by
* the timestamp update). The IN_LAZYMOD flag is set to force a write
* later if not now. If we write now, then clear both IN_MODIFIED and
* IN_LAZYMOD to reflect the presumably successful write, and if waitfor is
* set, then wait for the write to complete.
*/
int
ext2_update(vp, waitfor)
struct vnode *vp;
int waitfor;
{
struct ext2_sb_info *fs;
struct buf *bp;
struct inode *ip;
int error;
ext2_itimes(vp);
ip = VTOI(vp);
if ((ip->i_flag & IN_MODIFIED) == 0)
return (0);
ip->i_flag &= ~(IN_LAZYMOD | IN_MODIFIED);
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (0);
fs = ip->i_e2fs;
if ((error = bread(ip->i_devvp,
fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
(int)fs->s_blocksize, NOCRED, &bp)) != 0) {
brelse(bp);
return (error);
}
ext2_i2ei(ip, (struct ext2_inode *)((char *)bp->b_data +
EXT2_INODE_SIZE * ino_to_fsbo(fs, ip->i_number)));
if (waitfor && (vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
return (bwrite(bp));
else {
bdwrite(bp);
return (0);
}
}
#define SINGLE 0 /* index of single indirect block */
#define DOUBLE 1 /* index of double indirect block */
#define TRIPLE 2 /* index of triple indirect block */
/*
* Truncate the inode oip to at most length size, freeing the
* disk blocks.
*/
int
ext2_truncate(vp, length, flags, cred, td)
struct vnode *vp;
off_t length;
int flags;
struct ucred *cred;
struct thread *td;
{
struct vnode *ovp = vp;
int32_t lastblock;
struct inode *oip;
int32_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
int32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
struct ext2_sb_info *fs;
struct buf *bp;
int offset, size, level;
long count, nblocks, blocksreleased = 0;
int aflags, error, i, allerror;
off_t osize;
/*
printf("ext2_truncate called %d to %d\n", VTOI(ovp)->i_number, length);
*/ /*
* negative file sizes will totally break the code below and
* are not meaningful anyways.
*/
if (length < 0)
return EFBIG;
oip = VTOI(ovp);
if (ovp->v_type == VLNK &&
oip->i_size < ovp->v_mount->mnt_maxsymlinklen) {
#if DIAGNOSTIC
if (length != 0)
panic("ext2_truncate: partial truncate of symlink");
#endif
bzero((char *)&oip->i_shortlink, (u_int)oip->i_size);
oip->i_size = 0;
oip->i_flag |= IN_CHANGE | IN_UPDATE;
return (ext2_update(ovp, 1));
}
if (oip->i_size == length) {
oip->i_flag |= IN_CHANGE | IN_UPDATE;
return (ext2_update(ovp, 0));
}
fs = oip->i_e2fs;
osize = oip->i_size;
ext2_discard_prealloc(oip);
/*
* Lengthen the size of the file. We must ensure that the
* last byte of the file is allocated. Since the smallest
* value of oszie is 0, length will be at least 1.
*/
if (osize < length) {
if (length > oip->i_e2fs->fs_maxfilesize)
return (EFBIG);
offset = blkoff(fs, length - 1);
lbn = lblkno(fs, length - 1);
aflags = B_CLRBUF;
if (flags & IO_SYNC)
aflags |= B_SYNC;
vnode_pager_setsize(ovp, length);
if ((error = ext2_balloc(oip, lbn, offset + 1, cred, &bp,
aflags)) != 0)
return (error);
oip->i_size = length;
if (aflags & IO_SYNC)
bwrite(bp);
else
bawrite(bp);
oip->i_flag |= IN_CHANGE | IN_UPDATE;
return (ext2_update(ovp, 1));
}
/*
* Shorten 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 accessible again because
* of subsequent file growth.
*/
/* I don't understand the comment above */
offset = blkoff(fs, length);
if (offset == 0) {
oip->i_size = length;
} else {
lbn = lblkno(fs, length);
aflags = B_CLRBUF;
if (flags & IO_SYNC)
aflags |= B_SYNC;
if ((error = ext2_balloc(oip, lbn, offset, cred, &bp,
aflags)) != 0)
return (error);
oip->i_size = length;
size = blksize(fs, oip, lbn);
bzero((char *)bp->b_data + offset, (u_int)(size - offset));
allocbuf(bp, size);
if (aflags & IO_SYNC)
bwrite(bp);
else
bawrite(bp);
}
/*
* Calculate index into inode's block list of
* last direct and indirect blocks (if any)
* which we want to keep. Lastblock is -1 when
* the file is truncated to 0.
*/
lastblock = lblkno(fs, length + fs->s_blocksize - 1) - 1;
lastiblock[SINGLE] = lastblock - NDADDR;
lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
nblocks = btodb(fs->s_blocksize);
/*
* Update file and block pointers on disk before we start freeing
* blocks. If we crash before free'ing blocks below, the blocks
* will be returned to the free list. lastiblock values are also
* normalized to -1 for calls to ext2_indirtrunc below.
*/
bcopy((caddr_t)&oip->i_db[0], (caddr_t)oldblks, sizeof oldblks);
for (level = TRIPLE; level >= SINGLE; level--)
if (lastiblock[level] < 0) {
oip->i_ib[level] = 0;
lastiblock[level] = -1;
}
for (i = NDADDR - 1; i > lastblock; i--)
oip->i_db[i] = 0;
oip->i_flag |= IN_CHANGE | IN_UPDATE;
allerror = ext2_update(ovp, 1);
/*
* Having written the new inode to disk, save its new configuration
* and put back the old block pointers long enough to process them.
* Note that we save the new block configuration so we can check it
* when we are done.
*/
bcopy((caddr_t)&oip->i_db[0], (caddr_t)newblks, sizeof newblks);
bcopy((caddr_t)oldblks, (caddr_t)&oip->i_db[0], sizeof oldblks);
oip->i_size = osize;
error = vtruncbuf(ovp, cred, td, length, (int)fs->s_blocksize);
if (error && (allerror == 0))
allerror = error;
/*
* Indirect blocks first.
*/
indir_lbn[SINGLE] = -NDADDR;
indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
for (level = TRIPLE; level >= SINGLE; level--) {
bn = oip->i_ib[level];
if (bn != 0) {
error = ext2_indirtrunc(oip, indir_lbn[level],
fsbtodb(fs, bn), lastiblock[level], level, &count);
if (error)
allerror = error;
blocksreleased += count;
if (lastiblock[level] < 0) {
oip->i_ib[level] = 0;
ext2_blkfree(oip, bn, fs->s_frag_size);
blocksreleased += nblocks;
}
}
if (lastiblock[level] >= 0)
goto done;
}
/*
* All whole direct blocks or frags.
*/
for (i = NDADDR - 1; i > lastblock; i--) {
long bsize;
bn = oip->i_db[i];
if (bn == 0)
continue;
oip->i_db[i] = 0;
bsize = blksize(fs, oip, i);
ext2_blkfree(oip, bn, bsize);
blocksreleased += btodb(bsize);
}
if (lastblock < 0)
goto done;
/*
* Finally, look for a change in size of the
* last direct block; release any frags.
*/
bn = oip->i_db[lastblock];
if (bn != 0) {
long oldspace, newspace;
/*
* Calculate amount of space we're giving
* back as old block size minus new block size.
*/
oldspace = blksize(fs, oip, lastblock);
oip->i_size = length;
newspace = blksize(fs, oip, lastblock);
if (newspace == 0)
panic("itrunc: newspace");
if (oldspace - newspace > 0) {
/*
* Block number of space to be free'd is
* the old block # plus the number of frags
* required for the storage we're keeping.
*/
bn += numfrags(fs, newspace);
ext2_blkfree(oip, bn, oldspace - newspace);
blocksreleased += btodb(oldspace - newspace);
}
}
done:
#if DIAGNOSTIC
for (level = SINGLE; level <= TRIPLE; level++)
if (newblks[NDADDR + level] != oip->i_ib[level])
panic("itrunc1");
for (i = 0; i < NDADDR; i++)
if (newblks[i] != oip->i_db[i])
panic("itrunc2");
VI_LOCK(ovp);
if (length == 0 && (!TAILQ_EMPTY(&ovp->v_dirtyblkhd) ||
!TAILQ_EMPTY(&ovp->v_cleanblkhd)))
panic("itrunc3");
VI_UNLOCK(ovp);
#endif /* DIAGNOSTIC */
/*
* Put back the real size.
*/
oip->i_size = length;
oip->i_blocks -= blocksreleased;
if (oip->i_blocks < 0) /* sanity */
oip->i_blocks = 0;
oip->i_flag |= IN_CHANGE;
vnode_pager_setsize(ovp, length);
return (allerror);
}
/*
* Release blocks associated with the inode ip and stored in the indirect
* block bn. Blocks are free'd in LIFO order up to (but not including)
* lastbn. If level is greater than SINGLE, the block is an indirect block
* and recursive calls to indirtrunc must be used to cleanse other indirect
* blocks.
*
* NB: triple indirect blocks are untested.
*/
static int
ext2_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
struct inode *ip;
int32_t lbn, lastbn;
int32_t dbn;
int level;
long *countp;
{
struct buf *bp;
struct ext2_sb_info *fs = ip->i_e2fs;
struct vnode *vp;
int32_t *bap, *copy, nb, nlbn, last;
long blkcount, factor;
int i, nblocks, blocksreleased = 0;
int error = 0, allerror = 0;
/*
* Calculate index in current block of last
* block to be kept. -1 indicates the entire
* block so we need not calculate the index.
*/
factor = 1;
for (i = SINGLE; i < level; i++)
factor *= NINDIR(fs);
last = lastbn;
if (lastbn > 0)
last /= factor;
nblocks = btodb(fs->s_blocksize);
/*
* Get buffer of block pointers, zero those entries corresponding
* to blocks to be free'd, and update on disk copy first. Since
* double(triple) indirect before single(double) indirect, calls
* to bmap on these blocks will fail. However, we already have
* the on disk address, so we have to set the b_blkno field
* explicitly instead of letting bread do everything for us.
*/
vp = ITOV(ip);
bp = getblk(vp, lbn, (int)fs->s_blocksize, 0, 0, 0);
if (bp->b_flags & (B_DONE | B_DELWRI)) {
} else {
bp->b_iocmd = BIO_READ;
if (bp->b_bcount > bp->b_bufsize)
panic("ext2_indirtrunc: bad buffer size");
bp->b_blkno = dbn;
vfs_busy_pages(bp, 0);
bp->b_iooffset = dbtob(bp->b_blkno);
VOP_STRATEGY(vp, bp);
error = bufwait(bp);
}
if (error) {
brelse(bp);
*countp = 0;
return (error);
}
bap = (int32_t *)bp->b_data;
MALLOC(copy, int32_t *, fs->s_blocksize, M_TEMP, M_WAITOK);
bcopy((caddr_t)bap, (caddr_t)copy, (u_int)fs->s_blocksize);
bzero((caddr_t)&bap[last + 1],
(u_int)(NINDIR(fs) - (last + 1)) * sizeof (int32_t));
if (last == -1)
bp->b_flags |= B_INVAL;
error = bwrite(bp);
if (error)
allerror = error;
bap = copy;
/*
* Recursively free totally unused blocks.
*/
for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
i--, nlbn += factor) {
nb = bap[i];
if (nb == 0)
continue;
if (level > SINGLE) {
if ((error = ext2_indirtrunc(ip, nlbn,
fsbtodb(fs, nb), (int32_t)-1, level - 1, &blkcount)) != 0)
allerror = error;
blocksreleased += blkcount;
}
ext2_blkfree(ip, nb, fs->s_blocksize);
blocksreleased += nblocks;
}
/*
* Recursively free last partial block.
*/
if (level > SINGLE && lastbn >= 0) {
last = lastbn % factor;
nb = bap[i];
if (nb != 0) {
if ((error = ext2_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
last, level - 1, &blkcount)) != 0)
allerror = error;
blocksreleased += blkcount;
}
}
FREE(copy, M_TEMP);
*countp = blocksreleased;
return (allerror);
}
/*
* discard preallocated blocks
*/
int
ext2_inactive(ap)
struct vop_inactive_args /* {
struct vnode *a_vp;
struct thread *a_td;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
struct thread *td = ap->a_td;
int mode, error = 0;
ext2_discard_prealloc(ip);
if (prtactive && vrefcnt(vp) != 0)
vprint("ext2_inactive: pushing active", vp);
/*
* Ignore inodes related to stale file handles.
*/
if (ip->i_mode == 0)
goto out;
if (ip->i_nlink <= 0) {
(void) vn_write_suspend_wait(vp, NULL, V_WAIT);
error = ext2_truncate(vp, (off_t)0, 0, NOCRED, td);
ip->i_rdev = 0;
mode = ip->i_mode;
ip->i_mode = 0;
ip->i_flag |= IN_CHANGE | IN_UPDATE;
ext2_vfree(vp, ip->i_number, mode);
}
if (ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) {
if ((ip->i_flag & (IN_CHANGE | IN_UPDATE | IN_MODIFIED)) == 0 &&
vn_write_suspend_wait(vp, NULL, V_NOWAIT)) {
ip->i_flag &= ~IN_ACCESS;
} else {
(void) vn_write_suspend_wait(vp, NULL, V_WAIT);
ext2_update(vp, 0);
}
}
out:
VOP_UNLOCK(vp, 0, td);
/*
* If we are done with the inode, reclaim it
* so that it can be reused immediately.
*/
if (ip->i_mode == 0)
vrecycle(vp, NULL, td);
return (error);
}
/*
* Reclaim an inode so that it can be used for other purposes.
*/
int
ext2_reclaim(ap)
struct vop_reclaim_args /* {
struct vnode *a_vp;
struct thread *a_td;
} */ *ap;
{
struct inode *ip;
struct vnode *vp = ap->a_vp;
if (prtactive && vrefcnt(vp) != 0)
vprint("ufs_reclaim: pushing active", vp);
ip = VTOI(vp);
if (ip->i_flag & IN_LAZYMOD) {
ip->i_flag |= IN_MODIFIED;
ext2_update(vp, 0);
}
/*
* Remove the inode from its hash chain.
*/
ext2_ihashrem(ip);
/*
* Purge old data structures associated with the inode.
*/
if (ip->i_devvp) {
vrele(ip->i_devvp);
ip->i_devvp = 0;
}
FREE(vp->v_data, M_EXT2NODE);
vp->v_data = 0;
return (0);
}