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e2fsprogs
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e2fsprogs/lib/ext2fs/block.c

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/*
* block.c --- iterate over all blocks in an inode
*
* Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Library
* General Public License, version 2.
* %End-Header%
*/
#include "config.h"
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "ext2_fs.h"
#include "ext2fs.h"
struct block_context {
ext2_filsys fs;
int (*func)(ext2_filsys fs,
blk64_t *blocknr,
e2_blkcnt_t bcount,
blk64_t ref_blk,
int ref_offset,
void *priv_data);
e2_blkcnt_t bcount;
int bsize;
int flags;
errcode_t errcode;
char *ind_buf;
char *dind_buf;
char *tind_buf;
void *priv_data;
};
#define check_for_ro_violation_return(ctx, ret) \
do { \
if (((ctx)->flags & BLOCK_FLAG_READ_ONLY) && \
((ret) & BLOCK_CHANGED)) { \
(ctx)->errcode = EXT2_ET_RO_BLOCK_ITERATE; \
ret |= BLOCK_ABORT | BLOCK_ERROR; \
return ret; \
} \
} while (0)
#define check_for_ro_violation_goto(ctx, ret, label) \
do { \
if (((ctx)->flags & BLOCK_FLAG_READ_ONLY) && \
((ret) & BLOCK_CHANGED)) { \
(ctx)->errcode = EXT2_ET_RO_BLOCK_ITERATE; \
ret |= BLOCK_ABORT | BLOCK_ERROR; \
goto label; \
} \
} while (0)
static int block_iterate_ind(blk_t *ind_block, blk_t ref_block,
int ref_offset, struct block_context *ctx)
{
int ret = 0, changed = 0;
int i, flags, limit, offset;
blk_t *block_nr;
blk64_t blk64;
limit = ctx->fs->blocksize >> 2;
if (!(ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
!(ctx->flags & BLOCK_FLAG_DATA_ONLY)) {
blk64 = *ind_block;
ret = (*ctx->func)(ctx->fs, &blk64,
BLOCK_COUNT_IND, ref_block,
ref_offset, ctx->priv_data);
*ind_block = blk64;
}
check_for_ro_violation_return(ctx, ret);
if (!*ind_block || (ret & BLOCK_ABORT)) {
ctx->bcount += limit;
return ret;
}
if (*ind_block >= ext2fs_blocks_count(ctx->fs->super) ||
*ind_block < ctx->fs->super->s_first_data_block) {
ctx->errcode = EXT2_ET_BAD_IND_BLOCK;
ret |= BLOCK_ERROR;
return ret;
}
ctx->errcode = ext2fs_read_ind_block(ctx->fs, *ind_block,
ctx->ind_buf);
if (ctx->errcode) {
ret |= BLOCK_ERROR;
return ret;
}
block_nr = (blk_t *) ctx->ind_buf;
offset = 0;
if (ctx->flags & BLOCK_FLAG_APPEND) {
for (i = 0; i < limit; i++, ctx->bcount++, block_nr++) {
blk64 = *block_nr;
flags = (*ctx->func)(ctx->fs, &blk64, ctx->bcount,
*ind_block, offset,
ctx->priv_data);
*block_nr = blk64;
changed |= flags;
if (flags & BLOCK_ABORT) {
ret |= BLOCK_ABORT;
break;
}
offset += sizeof(blk_t);
}
} else {
for (i = 0; i < limit; i++, ctx->bcount++, block_nr++) {
if (*block_nr == 0)
goto skip_sparse;
blk64 = *block_nr;
flags = (*ctx->func)(ctx->fs, &blk64, ctx->bcount,
*ind_block, offset,
ctx->priv_data);
*block_nr = blk64;
changed |= flags;
if (flags & BLOCK_ABORT) {
ret |= BLOCK_ABORT;
break;
}
skip_sparse:
offset += sizeof(blk_t);
}
}
check_for_ro_violation_return(ctx, changed);
if (changed & BLOCK_CHANGED) {
ctx->errcode = ext2fs_write_ind_block(ctx->fs, *ind_block,
ctx->ind_buf);
if (ctx->errcode)
ret |= BLOCK_ERROR | BLOCK_ABORT;
}
if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
!(ctx->flags & BLOCK_FLAG_DATA_ONLY) &&
!(ret & BLOCK_ABORT)) {
blk64 = *ind_block;
ret |= (*ctx->func)(ctx->fs, &blk64,
BLOCK_COUNT_IND, ref_block,
ref_offset, ctx->priv_data);
*ind_block = blk64;
}
check_for_ro_violation_return(ctx, ret);
return ret;
}
static int block_iterate_dind(blk_t *dind_block, blk_t ref_block,
int ref_offset, struct block_context *ctx)
{
int ret = 0, changed = 0;
int i, flags, limit, offset;
blk_t *block_nr;
blk64_t blk64;
limit = ctx->fs->blocksize >> 2;
if (!(ctx->flags & (BLOCK_FLAG_DEPTH_TRAVERSE |
BLOCK_FLAG_DATA_ONLY))) {
blk64 = *dind_block;
ret = (*ctx->func)(ctx->fs, &blk64,
BLOCK_COUNT_DIND, ref_block,
ref_offset, ctx->priv_data);
*dind_block = blk64;
}
check_for_ro_violation_return(ctx, ret);
if (!*dind_block || (ret & BLOCK_ABORT)) {
ctx->bcount += limit*limit;
return ret;
}
if (*dind_block >= ext2fs_blocks_count(ctx->fs->super) ||
*dind_block < ctx->fs->super->s_first_data_block) {
ctx->errcode = EXT2_ET_BAD_DIND_BLOCK;
ret |= BLOCK_ERROR;
return ret;
}
ctx->errcode = ext2fs_read_ind_block(ctx->fs, *dind_block,
ctx->dind_buf);
if (ctx->errcode) {
ret |= BLOCK_ERROR;
return ret;
}
block_nr = (blk_t *) ctx->dind_buf;
offset = 0;
if (ctx->flags & BLOCK_FLAG_APPEND) {
for (i = 0; i < limit; i++, block_nr++) {
flags = block_iterate_ind(block_nr,
*dind_block, offset,
ctx);
changed |= flags;
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
break;
}
offset += sizeof(blk_t);
}
} else {
for (i = 0; i < limit; i++, block_nr++) {
if (*block_nr == 0) {
ctx->bcount += limit;
continue;
}
flags = block_iterate_ind(block_nr,
*dind_block, offset,
ctx);
changed |= flags;
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
break;
}
offset += sizeof(blk_t);
}
}
check_for_ro_violation_return(ctx, changed);
if (changed & BLOCK_CHANGED) {
ctx->errcode = ext2fs_write_ind_block(ctx->fs, *dind_block,
ctx->dind_buf);
if (ctx->errcode)
ret |= BLOCK_ERROR | BLOCK_ABORT;
}
if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
!(ctx->flags & BLOCK_FLAG_DATA_ONLY) &&
!(ret & BLOCK_ABORT)) {
blk64 = *dind_block;
ret |= (*ctx->func)(ctx->fs, &blk64,
BLOCK_COUNT_DIND, ref_block,
ref_offset, ctx->priv_data);
*dind_block = blk64;
}
check_for_ro_violation_return(ctx, ret);
return ret;
}
static int block_iterate_tind(blk_t *tind_block, blk_t ref_block,
int ref_offset, struct block_context *ctx)
{
int ret = 0, changed = 0;
int i, flags, limit, offset;
blk_t *block_nr;
blk64_t blk64;
limit = ctx->fs->blocksize >> 2;
if (!(ctx->flags & (BLOCK_FLAG_DEPTH_TRAVERSE |
BLOCK_FLAG_DATA_ONLY))) {
blk64 = *tind_block;
ret = (*ctx->func)(ctx->fs, &blk64,
BLOCK_COUNT_TIND, ref_block,
ref_offset, ctx->priv_data);
*tind_block = blk64;
}
check_for_ro_violation_return(ctx, ret);
if (!*tind_block || (ret & BLOCK_ABORT)) {
ctx->bcount += ((unsigned long long) limit)*limit*limit;
return ret;
}
if (*tind_block >= ext2fs_blocks_count(ctx->fs->super) ||
*tind_block < ctx->fs->super->s_first_data_block) {
ctx->errcode = EXT2_ET_BAD_TIND_BLOCK;
ret |= BLOCK_ERROR;
return ret;
}
ctx->errcode = ext2fs_read_ind_block(ctx->fs, *tind_block,
ctx->tind_buf);
if (ctx->errcode) {
ret |= BLOCK_ERROR;
return ret;
}
block_nr = (blk_t *) ctx->tind_buf;
offset = 0;
if (ctx->flags & BLOCK_FLAG_APPEND) {
for (i = 0; i < limit; i++, block_nr++) {
flags = block_iterate_dind(block_nr,
*tind_block,
offset, ctx);
changed |= flags;
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
break;
}
offset += sizeof(blk_t);
}
} else {
for (i = 0; i < limit; i++, block_nr++) {
if (*block_nr == 0) {
ctx->bcount += limit*limit;
continue;
}
flags = block_iterate_dind(block_nr,
*tind_block,
offset, ctx);
changed |= flags;
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
break;
}
offset += sizeof(blk_t);
}
}
check_for_ro_violation_return(ctx, changed);
if (changed & BLOCK_CHANGED) {
ctx->errcode = ext2fs_write_ind_block(ctx->fs, *tind_block,
ctx->tind_buf);
if (ctx->errcode)
ret |= BLOCK_ERROR | BLOCK_ABORT;
}
if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
!(ctx->flags & BLOCK_FLAG_DATA_ONLY) &&
!(ret & BLOCK_ABORT)) {
blk64 = *tind_block;
ret |= (*ctx->func)(ctx->fs, &blk64,
BLOCK_COUNT_TIND, ref_block,
ref_offset, ctx->priv_data);
*tind_block = blk64;
}
check_for_ro_violation_return(ctx, ret);
return ret;
}
errcode_t ext2fs_block_iterate3(ext2_filsys fs,
ext2_ino_t ino,
int flags,
char *block_buf,
int (*func)(ext2_filsys fs,
blk64_t *blocknr,
e2_blkcnt_t blockcnt,
blk64_t ref_blk,
int ref_offset,
void *priv_data),
void *priv_data)
{
int i;
int r, ret = 0;
struct ext2_inode inode;
errcode_t retval;
struct block_context ctx;
int limit;
blk64_t blk64;
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
ctx.errcode = ext2fs_read_inode(fs, ino, &inode);
if (ctx.errcode)
return ctx.errcode;
/*
* An inode with inline data has no blocks over which to
* iterate, so return an error code indicating this fact.
*/
if (inode.i_flags & EXT4_INLINE_DATA_FL)
return EXT2_ET_INLINE_DATA_CANT_ITERATE;
/*
* Check to see if we need to limit large files
*/
if (flags & BLOCK_FLAG_NO_LARGE) {
if (!LINUX_S_ISDIR(inode.i_mode) &&
(inode.i_size_high != 0))
return EXT2_ET_FILE_TOO_BIG;
}
limit = fs->blocksize >> 2;
ctx.fs = fs;
ctx.func = func;
ctx.priv_data = priv_data;
ctx.flags = flags;
ctx.bcount = 0;
if (block_buf) {
ctx.ind_buf = block_buf;
} else {
retval = ext2fs_get_array(3, fs->blocksize, &ctx.ind_buf);
if (retval)
return retval;
}
ctx.dind_buf = ctx.ind_buf + fs->blocksize;
ctx.tind_buf = ctx.dind_buf + fs->blocksize;
/*
* Iterate over the HURD translator block (if present)
*/
if ((fs->super->s_creator_os == EXT2_OS_HURD) &&
!(flags & BLOCK_FLAG_DATA_ONLY)) {
if (inode.osd1.hurd1.h_i_translator) {
blk64 = inode.osd1.hurd1.h_i_translator;
ret |= (*ctx.func)(fs, &blk64,
BLOCK_COUNT_TRANSLATOR,
0, 0, priv_data);
inode.osd1.hurd1.h_i_translator = (blk_t) blk64;
if (ret & BLOCK_ABORT)
goto abort_exit;
check_for_ro_violation_goto(&ctx, ret, abort_exit);
}
}
if (inode.i_flags & EXT4_EXTENTS_FL) {
ext2_extent_handle_t handle;
struct ext2fs_extent extent, next;
e2_blkcnt_t blockcnt = 0;
blk64_t blk, new_blk;
int op = EXT2_EXTENT_ROOT;
int uninit;
unsigned int j;
ctx.errcode = ext2fs_extent_open2(fs, ino, &inode, &handle);
if (ctx.errcode)
goto abort_exit;
while (1) {
if (op == EXT2_EXTENT_CURRENT)
ctx.errcode = 0;
else
ctx.errcode = ext2fs_extent_get(handle, op,
&extent);
if (ctx.errcode) {
if (ctx.errcode != EXT2_ET_EXTENT_NO_NEXT)
break;
ctx.errcode = 0;
if (!(flags & BLOCK_FLAG_APPEND))
break;
next_block_set:
blk = 0;
r = (*ctx.func)(fs, &blk, blockcnt,
0, 0, priv_data);
ret |= r;
check_for_ro_violation_goto(&ctx, ret,
extent_done);
if (r & BLOCK_CHANGED) {
ctx.errcode =
ext2fs_extent_set_bmap(handle,
(blk64_t) blockcnt++,
(blk64_t) blk, 0);
if (ctx.errcode || (ret & BLOCK_ABORT))
break;
if (blk)
goto next_block_set;
}
break;
}
op = EXT2_EXTENT_NEXT;
blk = extent.e_pblk;
if (!(extent.e_flags & EXT2_EXTENT_FLAGS_LEAF)) {
if (ctx.flags & BLOCK_FLAG_DATA_ONLY)
continue;
if ((!(extent.e_flags &
EXT2_EXTENT_FLAGS_SECOND_VISIT) &&
!(ctx.flags & BLOCK_FLAG_DEPTH_TRAVERSE)) ||
((extent.e_flags &
EXT2_EXTENT_FLAGS_SECOND_VISIT) &&
(ctx.flags & BLOCK_FLAG_DEPTH_TRAVERSE))) {
ret |= (*ctx.func)(fs, &blk,
-1, 0, 0, priv_data);
if (ret & BLOCK_CHANGED) {
extent.e_pblk = blk;
ctx.errcode =
ext2fs_extent_replace(handle, 0, &extent);
if (ctx.errcode)
break;
}
if (ret & BLOCK_ABORT)
break;
}
continue;
}
uninit = 0;
if (extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
uninit = EXT2_EXTENT_SET_BMAP_UNINIT;
/*
* Get the next extent before we start messing
* with the current extent
*/
retval = ext2fs_extent_get(handle, op, &next);
#if 0
printf("lblk %llu pblk %llu len %d blockcnt %llu\n",
extent.e_lblk, extent.e_pblk,
extent.e_len, blockcnt);
#endif
if (extent.e_lblk + extent.e_len <= (blk64_t) blockcnt)
continue;
if (extent.e_lblk > (blk64_t) blockcnt)
blockcnt = extent.e_lblk;
j = blockcnt - extent.e_lblk;
blk += j;
for (blockcnt = extent.e_lblk, j = 0;
j < extent.e_len;
blk++, blockcnt++, j++) {
new_blk = blk;
r = (*ctx.func)(fs, &new_blk, blockcnt,
0, 0, priv_data);
ret |= r;
check_for_ro_violation_goto(&ctx, ret,
extent_done);
if (r & BLOCK_CHANGED) {
ctx.errcode =
ext2fs_extent_set_bmap(handle,
(blk64_t) blockcnt,
new_blk, uninit);
if (ctx.errcode)
goto extent_done;
}
if (ret & BLOCK_ABORT)
goto extent_done;
}
if (retval == 0) {
extent = next;
op = EXT2_EXTENT_CURRENT;
}
}
extent_done:
ext2fs_extent_free(handle);
ret |= BLOCK_ERROR; /* ctx.errcode is always valid here */
goto errout;
}
/*
* Iterate over normal data blocks
*/
for (i = 0; i < EXT2_NDIR_BLOCKS ; i++, ctx.bcount++) {
if (inode.i_block[i] || (flags & BLOCK_FLAG_APPEND)) {
blk64 = inode.i_block[i];
ret |= (*ctx.func)(fs, &blk64, ctx.bcount, 0, i,
priv_data);
inode.i_block[i] = (blk_t) blk64;
if (ret & BLOCK_ABORT)
goto abort_exit;
}
}
check_for_ro_violation_goto(&ctx, ret, abort_exit);
if (inode.i_block[EXT2_IND_BLOCK] || (flags & BLOCK_FLAG_APPEND)) {
ret |= block_iterate_ind(&inode.i_block[EXT2_IND_BLOCK],
0, EXT2_IND_BLOCK, &ctx);
if (ret & BLOCK_ABORT)
goto abort_exit;
} else
ctx.bcount += limit;
if (inode.i_block[EXT2_DIND_BLOCK] || (flags & BLOCK_FLAG_APPEND)) {
ret |= block_iterate_dind(&inode.i_block[EXT2_DIND_BLOCK],
0, EXT2_DIND_BLOCK, &ctx);
if (ret & BLOCK_ABORT)
goto abort_exit;
} else
ctx.bcount += limit * limit;
if (inode.i_block[EXT2_TIND_BLOCK] || (flags & BLOCK_FLAG_APPEND)) {
ret |= block_iterate_tind(&inode.i_block[EXT2_TIND_BLOCK],
0, EXT2_TIND_BLOCK, &ctx);
if (ret & BLOCK_ABORT)
goto abort_exit;
}
abort_exit:
if (ret & BLOCK_CHANGED) {
retval = ext2fs_write_inode(fs, ino, &inode);
if (retval) {
ret |= BLOCK_ERROR;
ctx.errcode = retval;
}
}
errout:
if (!block_buf)
ext2fs_free_mem(&ctx.ind_buf);
return (ret & BLOCK_ERROR) ? ctx.errcode : 0;
}
/*
* Emulate the old ext2fs_block_iterate function!
*/
struct xlate64 {
int (*func)(ext2_filsys fs,
blk_t *blocknr,
e2_blkcnt_t blockcnt,
blk_t ref_blk,
int ref_offset,
void *priv_data);
void *real_private;
};
static int xlate64_func(ext2_filsys fs, blk64_t *blocknr,
e2_blkcnt_t blockcnt, blk64_t ref_blk,
int ref_offset, void *priv_data)
{
struct xlate64 *xl = (struct xlate64 *) priv_data;
int ret;
blk_t block32 = *blocknr;
ret = (*xl->func)(fs, &block32, blockcnt, (blk_t) ref_blk, ref_offset,
xl->real_private);
*blocknr = block32;
return ret;
}
errcode_t ext2fs_block_iterate2(ext2_filsys fs,
ext2_ino_t ino,
int flags,
char *block_buf,
int (*func)(ext2_filsys fs,
blk_t *blocknr,
e2_blkcnt_t blockcnt,
blk_t ref_blk,
int ref_offset,
void *priv_data),
void *priv_data)
{
struct xlate64 xl;
xl.real_private = priv_data;
xl.func = func;
return ext2fs_block_iterate3(fs, ino, flags, block_buf,
xlate64_func, &xl);
}
struct xlate {
int (*func)(ext2_filsys fs,
blk_t *blocknr,
int bcount,
void *priv_data);
void *real_private;
};
#ifdef __TURBOC__
#pragma argsused
#endif
static int xlate_func(ext2_filsys fs, blk_t *blocknr, e2_blkcnt_t blockcnt,
blk_t ref_block EXT2FS_ATTR((unused)),
int ref_offset EXT2FS_ATTR((unused)),
void *priv_data)
{
struct xlate *xl = (struct xlate *) priv_data;
return (*xl->func)(fs, blocknr, (int) blockcnt, xl->real_private);
}
errcode_t ext2fs_block_iterate(ext2_filsys fs,
ext2_ino_t ino,
int flags,
char *block_buf,
int (*func)(ext2_filsys fs,
blk_t *blocknr,
int blockcnt,
void *priv_data),
void *priv_data)
{
struct xlate xl;
xl.real_private = priv_data;
xl.func = func;
return ext2fs_block_iterate2(fs, ino, BLOCK_FLAG_NO_LARGE | flags,
block_buf, xlate_func, &xl);
}
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