/*
* Vnode op for writing.
*/
int
ext2fs_write(void *v)
{
struct vop_write_args *ap = v;
struct vnode *vp;
struct uio *uio;
struct inode *ip;
struct m_ext2fs *fs;
struct buf *bp;
int32_t lbn;
off_t osize;
int blkoffset, error, flags, ioflag, size, xfersize;
ssize_t resid, overrun;
ioflag = ap->a_ioflag;
uio = ap->a_uio;
vp = ap->a_vp;
ip = VTOI(vp);
#ifdef DIAGNOSTIC
if (uio->uio_rw != UIO_WRITE)
panic("%s: mode", "ext2fs_write");
#endif
/*
* If writing 0 bytes, succeed and do not change
* update time or file offset (standards compliance)
*/
if (uio->uio_resid == 0)
return (0);
switch (vp->v_type) {
case VREG:
if (ioflag & IO_APPEND)
uio->uio_offset = ext2fs_size(ip);
if ((ip->i_e2fs_flags & EXT2_APPEND) &&
uio->uio_offset != ext2fs_size(ip))
return (EPERM);
/* FALLTHROUGH */
case VLNK:
break;
case VDIR:
if ((ioflag & IO_SYNC) == 0)
panic("%s: nonsync dir write", "ext2fs_write");
break;
default:
panic("%s: type", "ext2fs_write");
}
fs = ip->i_e2fs;
if (uio->uio_offset < 0 ||
(u_int64_t)uio->uio_offset + uio->uio_resid >
((u_int64_t)0x80000000 * fs->e2fs_bsize - 1))
return (EFBIG);
/* do the filesize rlimit check */
if ((error = vn_fsizechk(vp, uio, ioflag, &overrun)))
return (error);
resid = uio->uio_resid;
osize = ext2fs_size(ip);
flags = ioflag & IO_SYNC ? B_SYNC : 0;
for (error = 0; uio->uio_resid > 0;) {
lbn = lblkno(fs, uio->uio_offset);
blkoffset = blkoff(fs, uio->uio_offset);
xfersize = fs->e2fs_bsize - blkoffset;
if (uio->uio_resid < xfersize)
xfersize = uio->uio_resid;
if (fs->e2fs_bsize > xfersize)
flags |= B_CLRBUF;
else
flags &= ~B_CLRBUF;
error = ext2fs_buf_alloc(ip,
lbn, blkoffset + xfersize, ap->a_cred, &bp, flags);
if (error)
break;
if (uio->uio_offset + xfersize > ext2fs_size(ip)) {
error = ext2fs_setsize(ip, uio->uio_offset + xfersize);
if (error)
break;
uvm_vnp_setsize(vp, ip->i_e2fs_size);
}
uvm_vnp_uncache(vp);
size = fs->e2fs_bsize - bp->b_resid;
if (size < xfersize)
xfersize = size;
error =
uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
if (ioflag & IO_SYNC)
(void)bwrite(bp);
else if (xfersize + blkoffset == fs->e2fs_bsize) {
if (doclusterwrite)
cluster_write(bp, &ip->i_ci, ext2fs_size(ip));
else
bawrite(bp);
} else
bdwrite(bp);
if (error || xfersize == 0)
break;
ip->i_flag |= IN_CHANGE | IN_UPDATE;
}
/*
* If we successfully wrote any data, and we are not the superuser
* we clear the setuid and setgid bits as a precaution against
* tampering.
*/
if (resid > uio->uio_resid && ap->a_cred && ap->a_cred->cr_uid != 0)
ip->i_e2fs_mode &= ~(ISUID | ISGID);
if (error) {
if (ioflag & IO_UNIT) {
(void)ext2fs_truncate(ip, osize,
ioflag & IO_SYNC, ap->a_cred);
uio->uio_offset -= resid - uio->uio_resid;
uio->uio_resid = resid;
}
} else if (resid > uio->uio_resid && (ioflag & IO_SYNC)) {
error = ext2fs_update(ip, NULL, NULL, 1);
}
/* correct the result for writes clamped by vn_fsizechk() */
uio->uio_resid += overrun;
return (error);
}
/*
* Truncate the inode oip to at most length size, freeing the
* disk blocks.
*/
int
ext2fs_truncate(struct inode *oip, off_t length, int flags, struct ucred *cred)
{
struct vnode *ovp = ITOV(oip);
int32_t lastblock;
int32_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
int32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
struct m_ext2fs *fs;
struct buf *bp;
int offset, size, level;
long count, nblocks, vflags, blocksreleased = 0;
int i;
int aflags, error, allerror;
off_t osize;
if (length < 0)
return (EINVAL);
if (ovp->v_type != VREG &&
ovp->v_type != VDIR &&
ovp->v_type != VLNK)
return (0);
if (ovp->v_type == VLNK && ext2fs_size(oip) < EXT2_MAXSYMLINKLEN) {
#ifdef DIAGNOSTIC
if (length != 0)
panic("ext2fs_truncate: partial truncate of symlink");
#endif
memset(&oip->i_e2din->e2di_shortlink, 0, ext2fs_size(oip));
(void)ext2fs_setsize(oip, 0);
oip->i_flag |= IN_CHANGE | IN_UPDATE;
return (ext2fs_update(oip, 1));
}
if (ext2fs_size(oip) == length) {
oip->i_flag |= IN_CHANGE | IN_UPDATE;
return (ext2fs_update(oip, 0));
}
fs = oip->i_e2fs;
osize = ext2fs_size(oip);
/*
* Lengthen the size of the file. We must ensure that the
* last byte of the file is allocated. Since the smallest
* value of osize is 0, length will be at least 1.
*/
if (osize < length) {
#if 0 /* XXX */
if (length > fs->fs_maxfilesize)
return (EFBIG);
#endif
offset = blkoff(fs, length - 1);
lbn = lblkno(fs, length - 1);
aflags = B_CLRBUF;
if (flags & IO_SYNC)
aflags |= B_SYNC;
error = ext2fs_buf_alloc(oip, lbn, offset + 1, cred, &bp,
aflags);
if (error)
return (error);
(void)ext2fs_setsize(oip, length);
uvm_vnp_setsize(ovp, length);
uvm_vnp_uncache(ovp);
if (aflags & B_SYNC)
bwrite(bp);
else
bawrite(bp);
oip->i_flag |= IN_CHANGE | IN_UPDATE;
return (ext2fs_update(oip, 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.
*/
offset = blkoff(fs, length);
if (offset == 0) {
(void)ext2fs_setsize(oip, length);
} else {
lbn = lblkno(fs, length);
aflags = B_CLRBUF;
if (flags & IO_SYNC)
aflags |= B_SYNC;
error = ext2fs_buf_alloc(oip, lbn, offset, cred, &bp,
aflags);
if (error)
return (error);
(void)ext2fs_setsize(oip, length);
size = fs->e2fs_bsize;
uvm_vnp_setsize(ovp, length);
uvm_vnp_uncache(ovp);
memset(bp->b_data + offset, 0, size - offset);
bp->b_bcount = size;
if (aflags & B_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->e2fs_bsize - 1) - 1;
lastiblock[SINGLE] = lastblock - NDADDR;
lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
nblocks = btodb(fs->e2fs_bsize);
/*
* 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 ext2fs_indirtrunc below.
*/
memcpy(oldblks, &oip->i_e2fs_blocks[0], sizeof(oldblks));
for (level = TRIPLE; level >= SINGLE; level--)
if (lastiblock[level] < 0) {
oip->i_e2fs_blocks[NDADDR + level] = 0;
lastiblock[level] = -1;
}
for (i = NDADDR - 1; i > lastblock; i--)
oip->i_e2fs_blocks[i] = 0;
oip->i_flag |= IN_CHANGE | IN_UPDATE;
if ((error = ext2fs_update(oip, 1)) != 0)
allerror = error;
/*
* 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.
*/
memcpy(newblks, &oip->i_e2fs_blocks[0], sizeof(newblks));
memcpy(&oip->i_e2fs_blocks[0], oldblks, sizeof(oldblks));
(void)ext2fs_setsize(oip, osize);
vflags = ((length > 0) ? V_SAVE : 0) | V_SAVEMETA;
allerror = vinvalbuf(ovp, vflags, cred, curproc, 0, 0);
/*
* 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 = letoh32(oip->i_e2fs_blocks[NDADDR + level]);
if (bn != 0) {
error = ext2fs_indirtrunc(oip, indir_lbn[level],
fsbtodb(fs, bn), lastiblock[level], level, &count);
if (error)
allerror = error;
blocksreleased += count;
if (lastiblock[level] < 0) {
oip->i_e2fs_blocks[NDADDR + level] = 0;
ext2fs_blkfree(oip, bn);
blocksreleased += nblocks;
}
}
if (lastiblock[level] >= 0)
goto done;
}
/*
* All whole direct blocks or frags.
*/
for (i = NDADDR - 1; i > lastblock; i--) {
bn = letoh32(oip->i_e2fs_blocks[i]);
if (bn == 0)
continue;
oip->i_e2fs_blocks[i] = 0;
ext2fs_blkfree(oip, bn);
blocksreleased += btodb(fs->e2fs_bsize);
}
done:
#ifdef DIAGNOSTIC
for (level = SINGLE; level <= TRIPLE; level++)
if (newblks[NDADDR + level] !=
oip->i_e2fs_blocks[NDADDR + level])
panic("ext2fs_truncate1");
for (i = 0; i < NDADDR; i++)
if (newblks[i] != oip->i_e2fs_blocks[i])
panic("ext2fs_truncate2");
if (length == 0 &&
(!LIST_EMPTY(&ovp->v_cleanblkhd) ||
!LIST_EMPTY(&ovp->v_dirtyblkhd)))
panic("ext2fs_truncate3");
#endif /* DIAGNOSTIC */
/*
* Put back the real size.
*/
(void)ext2fs_setsize(oip, length);
if (blocksreleased >= oip->i_e2fs_nblock)
oip->i_e2fs_nblock = 0;
else
oip->i_e2fs_nblock -= blocksreleased;
oip->i_flag |= IN_CHANGE;
return (allerror);
}
