mirror of
https://github.com/torvalds/linux.git
synced 2024-11-27 06:31:52 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
478 lines
11 KiB
C
478 lines
11 KiB
C
/*
|
|
* linux/fs/ufs/truncate.c
|
|
*
|
|
* Copyright (C) 1998
|
|
* Daniel Pirkl <daniel.pirkl@email.cz>
|
|
* Charles University, Faculty of Mathematics and Physics
|
|
*
|
|
* from
|
|
*
|
|
* linux/fs/ext2/truncate.c
|
|
*
|
|
* Copyright (C) 1992, 1993, 1994, 1995
|
|
* Remy Card (card@masi.ibp.fr)
|
|
* Laboratoire MASI - Institut Blaise Pascal
|
|
* Universite Pierre et Marie Curie (Paris VI)
|
|
*
|
|
* from
|
|
*
|
|
* linux/fs/minix/truncate.c
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
*
|
|
* Big-endian to little-endian byte-swapping/bitmaps by
|
|
* David S. Miller (davem@caip.rutgers.edu), 1995
|
|
*/
|
|
|
|
/*
|
|
* Real random numbers for secure rm added 94/02/18
|
|
* Idea from Pierre del Perugia <delperug@gla.ecoledoc.ibp.fr>
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/ufs_fs.h>
|
|
#include <linux/fcntl.h>
|
|
#include <linux/time.h>
|
|
#include <linux/stat.h>
|
|
#include <linux/string.h>
|
|
#include <linux/smp_lock.h>
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/sched.h>
|
|
|
|
#include "swab.h"
|
|
#include "util.h"
|
|
|
|
#undef UFS_TRUNCATE_DEBUG
|
|
|
|
#ifdef UFS_TRUNCATE_DEBUG
|
|
#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
|
|
#else
|
|
#define UFSD(x)
|
|
#endif
|
|
|
|
/*
|
|
* Secure deletion currently doesn't work. It interacts very badly
|
|
* with buffers shared with memory mappings, and for that reason
|
|
* can't be done in the truncate() routines. It should instead be
|
|
* done separately in "release()" before calling the truncate routines
|
|
* that will release the actual file blocks.
|
|
*
|
|
* Linus
|
|
*/
|
|
|
|
#define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift)
|
|
#define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift)
|
|
|
|
#define DATA_BUFFER_USED(bh) \
|
|
(atomic_read(&bh->b_count)>1 || buffer_locked(bh))
|
|
|
|
static int ufs_trunc_direct (struct inode * inode)
|
|
{
|
|
struct ufs_inode_info *ufsi = UFS_I(inode);
|
|
struct super_block * sb;
|
|
struct ufs_sb_private_info * uspi;
|
|
struct buffer_head * bh;
|
|
__fs32 * p;
|
|
unsigned frag1, frag2, frag3, frag4, block1, block2;
|
|
unsigned frag_to_free, free_count;
|
|
unsigned i, j, tmp;
|
|
int retry;
|
|
|
|
UFSD(("ENTER\n"))
|
|
|
|
sb = inode->i_sb;
|
|
uspi = UFS_SB(sb)->s_uspi;
|
|
|
|
frag_to_free = 0;
|
|
free_count = 0;
|
|
retry = 0;
|
|
|
|
frag1 = DIRECT_FRAGMENT;
|
|
frag4 = min_t(u32, UFS_NDIR_FRAGMENT, ufsi->i_lastfrag);
|
|
frag2 = ((frag1 & uspi->s_fpbmask) ? ((frag1 | uspi->s_fpbmask) + 1) : frag1);
|
|
frag3 = frag4 & ~uspi->s_fpbmask;
|
|
block1 = block2 = 0;
|
|
if (frag2 > frag3) {
|
|
frag2 = frag4;
|
|
frag3 = frag4 = 0;
|
|
}
|
|
else if (frag2 < frag3) {
|
|
block1 = ufs_fragstoblks (frag2);
|
|
block2 = ufs_fragstoblks (frag3);
|
|
}
|
|
|
|
UFSD(("frag1 %u, frag2 %u, block1 %u, block2 %u, frag3 %u, frag4 %u\n", frag1, frag2, block1, block2, frag3, frag4))
|
|
|
|
if (frag1 >= frag2)
|
|
goto next1;
|
|
|
|
/*
|
|
* Free first free fragments
|
|
*/
|
|
p = ufsi->i_u1.i_data + ufs_fragstoblks (frag1);
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
if (!tmp )
|
|
ufs_panic (sb, "ufs_trunc_direct", "internal error");
|
|
frag1 = ufs_fragnum (frag1);
|
|
frag2 = ufs_fragnum (frag2);
|
|
for (j = frag1; j < frag2; j++) {
|
|
bh = sb_find_get_block (sb, tmp + j);
|
|
if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) {
|
|
retry = 1;
|
|
brelse (bh);
|
|
goto next1;
|
|
}
|
|
bforget (bh);
|
|
}
|
|
inode->i_blocks -= (frag2-frag1) << uspi->s_nspfshift;
|
|
mark_inode_dirty(inode);
|
|
ufs_free_fragments (inode, tmp + frag1, frag2 - frag1);
|
|
frag_to_free = tmp + frag1;
|
|
|
|
next1:
|
|
/*
|
|
* Free whole blocks
|
|
*/
|
|
for (i = block1 ; i < block2; i++) {
|
|
p = ufsi->i_u1.i_data + i;
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
if (!tmp)
|
|
continue;
|
|
for (j = 0; j < uspi->s_fpb; j++) {
|
|
bh = sb_find_get_block(sb, tmp + j);
|
|
if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) {
|
|
retry = 1;
|
|
brelse (bh);
|
|
goto next2;
|
|
}
|
|
bforget (bh);
|
|
}
|
|
*p = 0;
|
|
inode->i_blocks -= uspi->s_nspb;
|
|
mark_inode_dirty(inode);
|
|
if (free_count == 0) {
|
|
frag_to_free = tmp;
|
|
free_count = uspi->s_fpb;
|
|
} else if (free_count > 0 && frag_to_free == tmp - free_count)
|
|
free_count += uspi->s_fpb;
|
|
else {
|
|
ufs_free_blocks (inode, frag_to_free, free_count);
|
|
frag_to_free = tmp;
|
|
free_count = uspi->s_fpb;
|
|
}
|
|
next2:;
|
|
}
|
|
|
|
if (free_count > 0)
|
|
ufs_free_blocks (inode, frag_to_free, free_count);
|
|
|
|
if (frag3 >= frag4)
|
|
goto next3;
|
|
|
|
/*
|
|
* Free last free fragments
|
|
*/
|
|
p = ufsi->i_u1.i_data + ufs_fragstoblks (frag3);
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
if (!tmp )
|
|
ufs_panic(sb, "ufs_truncate_direct", "internal error");
|
|
frag4 = ufs_fragnum (frag4);
|
|
for (j = 0; j < frag4; j++) {
|
|
bh = sb_find_get_block (sb, tmp + j);
|
|
if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) {
|
|
retry = 1;
|
|
brelse (bh);
|
|
goto next1;
|
|
}
|
|
bforget (bh);
|
|
}
|
|
*p = 0;
|
|
inode->i_blocks -= frag4 << uspi->s_nspfshift;
|
|
mark_inode_dirty(inode);
|
|
ufs_free_fragments (inode, tmp, frag4);
|
|
next3:
|
|
|
|
UFSD(("EXIT\n"))
|
|
return retry;
|
|
}
|
|
|
|
|
|
static int ufs_trunc_indirect (struct inode * inode, unsigned offset, __fs32 *p)
|
|
{
|
|
struct super_block * sb;
|
|
struct ufs_sb_private_info * uspi;
|
|
struct ufs_buffer_head * ind_ubh;
|
|
struct buffer_head * bh;
|
|
__fs32 * ind;
|
|
unsigned indirect_block, i, j, tmp;
|
|
unsigned frag_to_free, free_count;
|
|
int retry;
|
|
|
|
UFSD(("ENTER\n"))
|
|
|
|
sb = inode->i_sb;
|
|
uspi = UFS_SB(sb)->s_uspi;
|
|
|
|
frag_to_free = 0;
|
|
free_count = 0;
|
|
retry = 0;
|
|
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
if (!tmp)
|
|
return 0;
|
|
ind_ubh = ubh_bread(sb, tmp, uspi->s_bsize);
|
|
if (tmp != fs32_to_cpu(sb, *p)) {
|
|
ubh_brelse (ind_ubh);
|
|
return 1;
|
|
}
|
|
if (!ind_ubh) {
|
|
*p = 0;
|
|
return 0;
|
|
}
|
|
|
|
indirect_block = (DIRECT_BLOCK > offset) ? (DIRECT_BLOCK - offset) : 0;
|
|
for (i = indirect_block; i < uspi->s_apb; i++) {
|
|
ind = ubh_get_addr32 (ind_ubh, i);
|
|
tmp = fs32_to_cpu(sb, *ind);
|
|
if (!tmp)
|
|
continue;
|
|
for (j = 0; j < uspi->s_fpb; j++) {
|
|
bh = sb_find_get_block(sb, tmp + j);
|
|
if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *ind)) {
|
|
retry = 1;
|
|
brelse (bh);
|
|
goto next;
|
|
}
|
|
bforget (bh);
|
|
}
|
|
*ind = 0;
|
|
ubh_mark_buffer_dirty(ind_ubh);
|
|
if (free_count == 0) {
|
|
frag_to_free = tmp;
|
|
free_count = uspi->s_fpb;
|
|
} else if (free_count > 0 && frag_to_free == tmp - free_count)
|
|
free_count += uspi->s_fpb;
|
|
else {
|
|
ufs_free_blocks (inode, frag_to_free, free_count);
|
|
frag_to_free = tmp;
|
|
free_count = uspi->s_fpb;
|
|
}
|
|
inode->i_blocks -= uspi->s_nspb;
|
|
mark_inode_dirty(inode);
|
|
next:;
|
|
}
|
|
|
|
if (free_count > 0) {
|
|
ufs_free_blocks (inode, frag_to_free, free_count);
|
|
}
|
|
for (i = 0; i < uspi->s_apb; i++)
|
|
if (*ubh_get_addr32(ind_ubh,i))
|
|
break;
|
|
if (i >= uspi->s_apb) {
|
|
if (ubh_max_bcount(ind_ubh) != 1) {
|
|
retry = 1;
|
|
}
|
|
else {
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
*p = 0;
|
|
inode->i_blocks -= uspi->s_nspb;
|
|
mark_inode_dirty(inode);
|
|
ufs_free_blocks (inode, tmp, uspi->s_fpb);
|
|
ubh_bforget(ind_ubh);
|
|
ind_ubh = NULL;
|
|
}
|
|
}
|
|
if (IS_SYNC(inode) && ind_ubh && ubh_buffer_dirty(ind_ubh)) {
|
|
ubh_wait_on_buffer (ind_ubh);
|
|
ubh_ll_rw_block (WRITE, 1, &ind_ubh);
|
|
ubh_wait_on_buffer (ind_ubh);
|
|
}
|
|
ubh_brelse (ind_ubh);
|
|
|
|
UFSD(("EXIT\n"))
|
|
|
|
return retry;
|
|
}
|
|
|
|
static int ufs_trunc_dindirect (struct inode *inode, unsigned offset, __fs32 *p)
|
|
{
|
|
struct super_block * sb;
|
|
struct ufs_sb_private_info * uspi;
|
|
struct ufs_buffer_head * dind_bh;
|
|
unsigned i, tmp, dindirect_block;
|
|
__fs32 * dind;
|
|
int retry = 0;
|
|
|
|
UFSD(("ENTER\n"))
|
|
|
|
sb = inode->i_sb;
|
|
uspi = UFS_SB(sb)->s_uspi;
|
|
|
|
dindirect_block = (DIRECT_BLOCK > offset)
|
|
? ((DIRECT_BLOCK - offset) >> uspi->s_apbshift) : 0;
|
|
retry = 0;
|
|
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
if (!tmp)
|
|
return 0;
|
|
dind_bh = ubh_bread(sb, tmp, uspi->s_bsize);
|
|
if (tmp != fs32_to_cpu(sb, *p)) {
|
|
ubh_brelse (dind_bh);
|
|
return 1;
|
|
}
|
|
if (!dind_bh) {
|
|
*p = 0;
|
|
return 0;
|
|
}
|
|
|
|
for (i = dindirect_block ; i < uspi->s_apb ; i++) {
|
|
dind = ubh_get_addr32 (dind_bh, i);
|
|
tmp = fs32_to_cpu(sb, *dind);
|
|
if (!tmp)
|
|
continue;
|
|
retry |= ufs_trunc_indirect (inode, offset + (i << uspi->s_apbshift), dind);
|
|
ubh_mark_buffer_dirty(dind_bh);
|
|
}
|
|
|
|
for (i = 0; i < uspi->s_apb; i++)
|
|
if (*ubh_get_addr32 (dind_bh, i))
|
|
break;
|
|
if (i >= uspi->s_apb) {
|
|
if (ubh_max_bcount(dind_bh) != 1)
|
|
retry = 1;
|
|
else {
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
*p = 0;
|
|
inode->i_blocks -= uspi->s_nspb;
|
|
mark_inode_dirty(inode);
|
|
ufs_free_blocks (inode, tmp, uspi->s_fpb);
|
|
ubh_bforget(dind_bh);
|
|
dind_bh = NULL;
|
|
}
|
|
}
|
|
if (IS_SYNC(inode) && dind_bh && ubh_buffer_dirty(dind_bh)) {
|
|
ubh_wait_on_buffer (dind_bh);
|
|
ubh_ll_rw_block (WRITE, 1, &dind_bh);
|
|
ubh_wait_on_buffer (dind_bh);
|
|
}
|
|
ubh_brelse (dind_bh);
|
|
|
|
UFSD(("EXIT\n"))
|
|
|
|
return retry;
|
|
}
|
|
|
|
static int ufs_trunc_tindirect (struct inode * inode)
|
|
{
|
|
struct ufs_inode_info *ufsi = UFS_I(inode);
|
|
struct super_block * sb;
|
|
struct ufs_sb_private_info * uspi;
|
|
struct ufs_buffer_head * tind_bh;
|
|
unsigned tindirect_block, tmp, i;
|
|
__fs32 * tind, * p;
|
|
int retry;
|
|
|
|
UFSD(("ENTER\n"))
|
|
|
|
sb = inode->i_sb;
|
|
uspi = UFS_SB(sb)->s_uspi;
|
|
retry = 0;
|
|
|
|
tindirect_block = (DIRECT_BLOCK > (UFS_NDADDR + uspi->s_apb + uspi->s_2apb))
|
|
? ((DIRECT_BLOCK - UFS_NDADDR - uspi->s_apb - uspi->s_2apb) >> uspi->s_2apbshift) : 0;
|
|
p = ufsi->i_u1.i_data + UFS_TIND_BLOCK;
|
|
if (!(tmp = fs32_to_cpu(sb, *p)))
|
|
return 0;
|
|
tind_bh = ubh_bread (sb, tmp, uspi->s_bsize);
|
|
if (tmp != fs32_to_cpu(sb, *p)) {
|
|
ubh_brelse (tind_bh);
|
|
return 1;
|
|
}
|
|
if (!tind_bh) {
|
|
*p = 0;
|
|
return 0;
|
|
}
|
|
|
|
for (i = tindirect_block ; i < uspi->s_apb ; i++) {
|
|
tind = ubh_get_addr32 (tind_bh, i);
|
|
retry |= ufs_trunc_dindirect(inode, UFS_NDADDR +
|
|
uspi->s_apb + ((i + 1) << uspi->s_2apbshift), tind);
|
|
ubh_mark_buffer_dirty(tind_bh);
|
|
}
|
|
for (i = 0; i < uspi->s_apb; i++)
|
|
if (*ubh_get_addr32 (tind_bh, i))
|
|
break;
|
|
if (i >= uspi->s_apb) {
|
|
if (ubh_max_bcount(tind_bh) != 1)
|
|
retry = 1;
|
|
else {
|
|
tmp = fs32_to_cpu(sb, *p);
|
|
*p = 0;
|
|
inode->i_blocks -= uspi->s_nspb;
|
|
mark_inode_dirty(inode);
|
|
ufs_free_blocks (inode, tmp, uspi->s_fpb);
|
|
ubh_bforget(tind_bh);
|
|
tind_bh = NULL;
|
|
}
|
|
}
|
|
if (IS_SYNC(inode) && tind_bh && ubh_buffer_dirty(tind_bh)) {
|
|
ubh_wait_on_buffer (tind_bh);
|
|
ubh_ll_rw_block (WRITE, 1, &tind_bh);
|
|
ubh_wait_on_buffer (tind_bh);
|
|
}
|
|
ubh_brelse (tind_bh);
|
|
|
|
UFSD(("EXIT\n"))
|
|
return retry;
|
|
}
|
|
|
|
void ufs_truncate (struct inode * inode)
|
|
{
|
|
struct ufs_inode_info *ufsi = UFS_I(inode);
|
|
struct super_block * sb;
|
|
struct ufs_sb_private_info * uspi;
|
|
struct buffer_head * bh;
|
|
unsigned offset;
|
|
int err, retry;
|
|
|
|
UFSD(("ENTER\n"))
|
|
sb = inode->i_sb;
|
|
uspi = UFS_SB(sb)->s_uspi;
|
|
|
|
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
|
|
return;
|
|
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
|
|
return;
|
|
lock_kernel();
|
|
while (1) {
|
|
retry = ufs_trunc_direct(inode);
|
|
retry |= ufs_trunc_indirect (inode, UFS_IND_BLOCK,
|
|
(__fs32 *) &ufsi->i_u1.i_data[UFS_IND_BLOCK]);
|
|
retry |= ufs_trunc_dindirect (inode, UFS_IND_BLOCK + uspi->s_apb,
|
|
(__fs32 *) &ufsi->i_u1.i_data[UFS_DIND_BLOCK]);
|
|
retry |= ufs_trunc_tindirect (inode);
|
|
if (!retry)
|
|
break;
|
|
if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
|
|
ufs_sync_inode (inode);
|
|
blk_run_address_space(inode->i_mapping);
|
|
yield();
|
|
}
|
|
offset = inode->i_size & uspi->s_fshift;
|
|
if (offset) {
|
|
bh = ufs_bread (inode, inode->i_size >> uspi->s_fshift, 0, &err);
|
|
if (bh) {
|
|
memset (bh->b_data + offset, 0, uspi->s_fsize - offset);
|
|
mark_buffer_dirty (bh);
|
|
brelse (bh);
|
|
}
|
|
}
|
|
inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
|
|
ufsi->i_lastfrag = DIRECT_FRAGMENT;
|
|
unlock_kernel();
|
|
mark_inode_dirty(inode);
|
|
UFSD(("EXIT\n"))
|
|
}
|