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e2fsprogs/resize/resize2fs.c
Theodore Ts'o 1333fe9344 ChangeLog, resize2fs.c: 
resize2fs.c: Rename max to max_groups and max_dirs to avoid possible
  	conflicts with a cpp macro named "max".
1998-09-03 00:26:49 +00:00

1343 lines
34 KiB
C
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/*
* resize2fs.c --- ext2 main routine
*
* Copyright (C) 1997 Theodore Ts'o
*
* %Begin-Header%
* All rights reserved.
* %End-Header%
*/
/*
* Resizing a filesystem consists of the following phases:
*
* 1. Adjust superblock and write out new parts of the inode
* table
* 2. Determine blocks which need to be relocated, and copy the
* contents of blocks from their old locations to the new ones.
* 3. Scan the inode table, doing the following:
* a. If blocks have been moved, update the block
* pointers in the inodes and indirect blocks to
* point at the new block locations.
* b. If parts of the inode table need to be evacuated,
* copy inodes from their old locations to their
* new ones.
* c. If (b) needs to be done, note which blocks contain
* directory information, since we will need to
* update the directory information.
* 4. Update the directory blocks with the new inode locations.
* 5. Move the inode tables, if necessary.
*/
#include "resize2fs.h"
#ifdef linux /* Kludge for debugging */
#define RESIZE2FS_DEBUG
#endif
static errcode_t adjust_superblock(ext2_resize_t rfs, blk_t new_size);
static errcode_t blocks_to_move(ext2_resize_t rfs);
static errcode_t block_mover(ext2_resize_t rfs);
static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
static errcode_t inode_ref_fix(ext2_resize_t rfs);
static errcode_t move_itables(ext2_resize_t rfs);
static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
/*
* Some helper CPP macros
*/
#define FS_BLOCK_BM(fs, i) ((fs)->group_desc[(i)].bg_block_bitmap)
#define FS_INODE_BM(fs, i) ((fs)->group_desc[(i)].bg_inode_bitmap)
#define FS_INODE_TB(fs, i) ((fs)->group_desc[(i)].bg_inode_table)
#define IS_BLOCK_BM(fs, i, blk) ((blk) == FS_BLOCK_BM((fs),(i)))
#define IS_INODE_BM(fs, i, blk) ((blk) == FS_INODE_BM((fs),(i)))
#define IS_INODE_TB(fs, i, blk) (((blk) >= FS_INODE_TB((fs), (i))) && \
((blk) < (FS_INODE_TB((fs), (i)) + \
(fs)->inode_blocks_per_group)))
/*
* This is the top-level routine which does the dirty deed....
*/
errcode_t resize_fs(ext2_filsys fs, blk_t new_size, int flags,
errcode_t (*progress)(ext2_resize_t rfs, int pass,
unsigned long cur,
unsigned long max_val))
{
ext2_resize_t rfs;
errcode_t retval;
retval = ext2fs_read_bitmaps(fs);
if (retval)
return retval;
/*
* Create the data structure
*/
retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct),
(void **) &rfs);
if (retval)
return retval;
memset(rfs, 0, sizeof(struct ext2_resize_struct));
rfs->old_fs = fs;
rfs->flags = flags;
rfs->itable_buf = 0;
rfs->progress = progress;
retval = ext2fs_dup_handle(fs, &rfs->new_fs);
if (retval)
goto errout;
retval = adjust_superblock(rfs, new_size);
if (retval)
goto errout;
retval = blocks_to_move(rfs);
if (retval)
goto errout;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_BMOVE)
printf("Number of free blocks: %d/%d, Needed: %d\n",
rfs->old_fs->super->s_free_blocks_count,
rfs->new_fs->super->s_free_blocks_count,
rfs->needed_blocks);
#endif
retval = block_mover(rfs);
if (retval)
goto errout;
retval = inode_scan_and_fix(rfs);
if (retval)
goto errout;
retval = inode_ref_fix(rfs);
if (retval)
goto errout;
retval = ext2fs_calculate_summary_stats(rfs->new_fs);
if (retval)
goto errout;
retval = move_itables(rfs);
if (retval)
goto errout;
retval = ext2fs_close(rfs->new_fs);
if (retval)
goto errout;
rfs->flags = flags;
ext2fs_free(rfs->old_fs);
if (rfs->itable_buf)
ext2fs_free_mem((void **) &rfs->itable_buf);
ext2fs_free_mem((void **) &rfs);
return 0;
errout:
if (rfs->new_fs)
ext2fs_free(rfs->new_fs);
if (rfs->itable_buf)
ext2fs_free_mem((void **) &rfs->itable_buf);
ext2fs_free_mem((void **) &rfs);
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 1.
*
* In this phase we adjust the in-memory superblock information, and
* initialize any new parts of the inode table. The new parts of the
* inode table are created in virgin disk space, so we can abort here
* without any side effects.
* --------------------------------------------------------------------
*/
/*
* This routine adjusts the superblock and other data structures...
*/
static errcode_t adjust_superblock(ext2_resize_t rfs, blk_t new_size)
{
ext2_filsys fs;
int overhead = 0;
int rem, adj = 0;
errcode_t retval;
ino_t real_end;
blk_t blk, group_block;
unsigned long i, j;
int old_numblocks, numblocks, adjblocks;
unsigned long max_group;
fs = rfs->new_fs;
fs->super->s_blocks_count = new_size;
ext2fs_mark_super_dirty(fs);
ext2fs_mark_bb_dirty(fs);
ext2fs_mark_ib_dirty(fs);
retry:
fs->group_desc_count = (fs->super->s_blocks_count -
fs->super->s_first_data_block +
EXT2_BLOCKS_PER_GROUP(fs->super) - 1)
/ EXT2_BLOCKS_PER_GROUP(fs->super);
if (fs->group_desc_count == 0)
return EXT2_ET_TOOSMALL;
fs->desc_blocks = (fs->group_desc_count +
EXT2_DESC_PER_BLOCK(fs->super) - 1)
/ EXT2_DESC_PER_BLOCK(fs->super);
/*
* Overhead is the number of bookkeeping blocks per group. It
* includes the superblock backup, the group descriptor
* backups, the inode bitmap, the block bitmap, and the inode
* table.
*
* XXX Not all block groups need the descriptor blocks, but
* being clever is tricky...
*/
overhead = 3 + fs->desc_blocks + fs->inode_blocks_per_group;
/*
* See if the last group is big enough to support the
* necessary data structures. If not, we need to get rid of
* it.
*/
rem = (fs->super->s_blocks_count - fs->super->s_first_data_block) %
fs->super->s_blocks_per_group;
if ((fs->group_desc_count == 1) && rem && (rem < overhead))
return EXT2_ET_TOOSMALL;
if (rem && (rem < overhead+50)) {
fs->super->s_blocks_count -= rem;
goto retry;
}
/*
* Adjust the number of inodes
*/
fs->super->s_inodes_count = fs->super->s_inodes_per_group *
fs->group_desc_count;
/*
* Adjust the number of free blocks
*/
blk = rfs->old_fs->super->s_blocks_count;
if (blk > fs->super->s_blocks_count)
fs->super->s_free_blocks_count -=
(blk - fs->super->s_blocks_count);
else
fs->super->s_free_blocks_count +=
(fs->super->s_blocks_count - blk);
/*
* Adjust the number of reserved blocks
*/
blk = rfs->old_fs->super->s_r_blocks_count * 100 /
rfs->old_fs->super->s_blocks_count;
fs->super->s_r_blocks_count = ((fs->super->s_blocks_count * blk)
/ 100);
/*
* Adjust the bitmaps for size
*/
retval = ext2fs_resize_inode_bitmap(fs->super->s_inodes_count,
fs->super->s_inodes_count,
fs->inode_map);
if (retval) goto errout;
real_end = ((EXT2_BLOCKS_PER_GROUP(fs->super)
* fs->group_desc_count)) - 1 +
fs->super->s_first_data_block;
retval = ext2fs_resize_block_bitmap(fs->super->s_blocks_count-1,
real_end, fs->block_map);
if (retval) goto errout;
/*
* Reallocate the group descriptors as necessary.
*/
if (rfs->old_fs->desc_blocks != fs->desc_blocks) {
retval = ext2fs_resize_mem(rfs->old_fs->desc_blocks *
fs->blocksize,
fs->desc_blocks * fs->blocksize,
(void **) &fs->group_desc);
if (retval)
goto errout;
}
/*
* Check to make sure there are enough inodes
*/
if ((rfs->old_fs->super->s_inodes_count -
rfs->old_fs->super->s_free_inodes_count) >
rfs->new_fs->super->s_inodes_count) {
retval = ENOSPC;
goto errout;
}
/*
* If we are shrinking the number block groups, we're done and
* can exit now.
*/
if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
retval = 0;
goto errout;
}
/*
* Fix the count of the last (old) block group
*/
old_numblocks = (rfs->old_fs->super->s_blocks_count -
rfs->old_fs->super->s_first_data_block) %
rfs->old_fs->super->s_blocks_per_group;
if (!old_numblocks)
old_numblocks = rfs->old_fs->super->s_blocks_per_group;
if (rfs->old_fs->group_desc_count == fs->group_desc_count) {
numblocks = (rfs->new_fs->super->s_blocks_count -
rfs->new_fs->super->s_first_data_block) %
rfs->new_fs->super->s_blocks_per_group;
if (!numblocks)
numblocks = rfs->new_fs->super->s_blocks_per_group;
} else
numblocks = rfs->new_fs->super->s_blocks_per_group;
i = rfs->old_fs->group_desc_count - 1;
fs->group_desc[i].bg_free_blocks_count += (numblocks-old_numblocks);
/*
* If the number of block groups is staying the same, we're
* done and can exit now. (If the number block groups is
* shrinking, we had exited earlier.)
*/
if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
retval = 0;
goto errout;
}
/*
* Initialize the new block group descriptors
*/
retval = ext2fs_get_mem(fs->blocksize * fs->inode_blocks_per_group,
(void **) &rfs->itable_buf);
if (retval)
goto errout;
memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
group_block = fs->super->s_first_data_block +
rfs->old_fs->group_desc_count * fs->super->s_blocks_per_group;
adj = rfs->old_fs->group_desc_count;
max_group = fs->group_desc_count - adj;
if (rfs->progress) {
retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
0, max_group);
if (retval)
goto errout;
}
for (i = rfs->old_fs->group_desc_count;
i < fs->group_desc_count; i++) {
memset(&fs->group_desc[i], 0,
sizeof(struct ext2_group_desc));
adjblocks = 0;
if (i == fs->group_desc_count-1) {
numblocks = (fs->super->s_blocks_count -
fs->super->s_first_data_block) %
fs->super->s_blocks_per_group;
if (!numblocks)
numblocks = fs->super->s_blocks_per_group;
} else
numblocks = fs->super->s_blocks_per_group;
if (ext2fs_bg_has_super(fs, i)) {
for (j=0; j < fs->desc_blocks+1; j++)
ext2fs_mark_block_bitmap(fs->block_map,
group_block + j);
adjblocks = 1 + fs->desc_blocks;
}
adjblocks += 2 + fs->inode_blocks_per_group;
numblocks -= adjblocks;
fs->super->s_free_blocks_count -= adjblocks;
fs->super->s_free_inodes_count +=
fs->super->s_inodes_per_group;
fs->group_desc[i].bg_free_blocks_count = numblocks;
fs->group_desc[i].bg_free_inodes_count =
fs->super->s_inodes_per_group;
fs->group_desc[i].bg_used_dirs_count = 0;
retval = ext2fs_allocate_group_table(fs, i, 0);
if (retval) goto errout;
/*
* Write out the new inode table
*/
retval = io_channel_write_blk(fs->io,
fs->group_desc[i].bg_inode_table,
fs->inode_blocks_per_group,
rfs->itable_buf);
if (retval) goto errout;
io_channel_flush(fs->io);
if (rfs->progress) {
retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
i - adj + 1, max_group);
if (retval)
goto errout;
}
group_block += fs->super->s_blocks_per_group;
}
io_channel_flush(fs->io);
retval = 0;
errout:
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 2.
*
* In this phase we adjust determine which blocks need to be moved, in
* blocks_to_move(). We then copy the blocks to their ultimate new
* destinations using block_mover(). Since we are copying blocks to
* their new locations, again during this pass we can abort without
* any problems.
* --------------------------------------------------------------------
*/
/*
* This helper function creates a block bitmap with all of the
* filesystem meta-data blocks.
*/
static errcode_t mark_table_blocks(ext2_filsys fs,
ext2fs_block_bitmap *ret_bmap)
{
blk_t block, b;
int i,j;
ext2fs_block_bitmap bmap;
errcode_t retval;
retval = ext2fs_allocate_block_bitmap(fs, "meta-data blocks", &bmap);
if (retval)
return retval;
block = fs->super->s_first_data_block;
for (i = 0; i < fs->group_desc_count; i++) {
if (ext2fs_bg_has_super(fs, i)) {
/*
* Mark this group's copy of the superblock
*/
ext2fs_mark_block_bitmap(bmap, block);
/*
* Mark this group's copy of the descriptors
*/
for (j = 0; j < fs->desc_blocks; j++)
ext2fs_mark_block_bitmap(bmap, block + j + 1);
}
/*
* Mark the blocks used for the inode table
*/
for (j = 0, b = fs->group_desc[i].bg_inode_table;
j < fs->inode_blocks_per_group;
j++, b++)
ext2fs_mark_block_bitmap(bmap, b);
/*
* Mark block used for the block bitmap
*/
ext2fs_mark_block_bitmap(bmap,
fs->group_desc[i].bg_block_bitmap);
/*
* Mark block used for the inode bitmap
*/
ext2fs_mark_block_bitmap(bmap,
fs->group_desc[i].bg_inode_bitmap);
block += fs->super->s_blocks_per_group;
}
*ret_bmap = bmap;
return 0;
}
/*
* This routine marks and unmarks reserved blocks in the new block
* bitmap. It also determines which blocks need to be moved and
* places this information into the move_blocks bitmap.
*/
static errcode_t blocks_to_move(ext2_resize_t rfs)
{
int i, j, max_groups;
blk_t blk, group_blk;
unsigned long old_blocks, new_blocks;
errcode_t retval;
ext2_filsys fs, old_fs;
ext2fs_block_bitmap meta_bmap;
fs = rfs->new_fs;
old_fs = rfs->old_fs;
if (old_fs->super->s_blocks_count > fs->super->s_blocks_count)
fs = rfs->old_fs;
retval = ext2fs_allocate_block_bitmap(fs, "reserved blocks",
&rfs->reserve_blocks);
if (retval)
return retval;
retval = ext2fs_allocate_block_bitmap(fs, "blocks to be moved",
&rfs->move_blocks);
if (retval)
return retval;
retval = mark_table_blocks(old_fs, &meta_bmap);
if (retval)
return retval;
fs = rfs->new_fs;
/*
* If we're shrinking the filesystem, we need to move all of
* the blocks that don't fit any more
*/
for (blk = fs->super->s_blocks_count;
blk < old_fs->super->s_blocks_count; blk++) {
if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap(meta_bmap, blk)) {
ext2fs_mark_block_bitmap(rfs->move_blocks, blk);
rfs->needed_blocks++;
}
ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk);
}
old_blocks = old_fs->desc_blocks;
new_blocks = fs->desc_blocks;
if (old_blocks == new_blocks) {
retval = 0;
goto errout;
}
max_groups = fs->group_desc_count;
if (max_groups > old_fs->group_desc_count)
max_groups = old_fs->group_desc_count;
group_blk = old_fs->super->s_first_data_block;
/*
* If we're reducing the number of descriptor blocks, this
* makes life easy. :-) We just have to mark some extra
* blocks as free.
*/
if (old_blocks > new_blocks) {
for (i = 0; i < max_groups; i++) {
if (!ext2fs_bg_has_super(fs, i)) {
group_blk += fs->super->s_blocks_per_group;
continue;
}
for (blk = group_blk+1+new_blocks;
blk < group_blk+1+old_blocks; blk++) {
ext2fs_unmark_block_bitmap(fs->block_map,
blk);
rfs->needed_blocks--;
}
group_blk += fs->super->s_blocks_per_group;
}
retval = 0;
goto errout;
}
/*
* If we're increasing the number of descriptor blocks, life
* gets interesting....
*/
for (i = 0; i < max_groups; i++) {
if (!ext2fs_bg_has_super(fs, i))
goto next_group;
for (blk = group_blk;
blk < group_blk + 1 + new_blocks; blk++) {
ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk);
ext2fs_mark_block_bitmap(fs->block_map, blk);
/*
* Check to see if we overlap with the inode
* or block bitmap, or the inode tables. If
* not, and the block is in use, then mark it
* as a block to be moved.
*/
if (IS_BLOCK_BM(fs, i, blk)) {
FS_BLOCK_BM(fs, i) = 0;
rfs->needed_blocks++;
} else if (IS_INODE_BM(fs, i, blk)) {
FS_INODE_BM(fs, i) = 0;
rfs->needed_blocks++;
} else if (IS_INODE_TB(fs, i, blk)) {
FS_INODE_TB(fs, i) = 0;
rfs->needed_blocks++;
} else if (ext2fs_test_block_bitmap(old_fs->block_map,
blk) &&
!ext2fs_test_block_bitmap(meta_bmap, blk)) {
ext2fs_mark_block_bitmap(rfs->move_blocks,
blk);
rfs->needed_blocks++;
}
}
if (fs->group_desc[i].bg_inode_table &&
fs->group_desc[i].bg_inode_bitmap &&
fs->group_desc[i].bg_block_bitmap)
goto next_group;
/*
* Reserve the existing meta blocks that we know
* aren't to be moved.
*/
if (fs->group_desc[i].bg_block_bitmap)
ext2fs_mark_block_bitmap(rfs->reserve_blocks,
fs->group_desc[i].bg_block_bitmap);
if (fs->group_desc[i].bg_inode_bitmap)
ext2fs_mark_block_bitmap(rfs->reserve_blocks,
fs->group_desc[i].bg_inode_bitmap);
if (fs->group_desc[i].bg_inode_table)
for (blk = fs->group_desc[i].bg_inode_table, j=0;
j < fs->inode_blocks_per_group ; j++, blk++)
ext2fs_mark_block_bitmap(rfs->reserve_blocks,
blk);
/*
* Allocate the missing data structures
*/
retval = ext2fs_allocate_group_table(fs, i,
rfs->reserve_blocks);
if (retval)
goto errout;
/*
* For those structures that have changed, we need to
* do bookkeepping.
*/
if (FS_BLOCK_BM(old_fs, i) !=
(blk = FS_BLOCK_BM(fs, i))) {
ext2fs_mark_block_bitmap(fs->block_map, blk);
if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap(meta_bmap, blk))
ext2fs_mark_block_bitmap(rfs->move_blocks,
blk);
}
if (FS_INODE_BM(old_fs, i) !=
(blk = FS_INODE_BM(fs, i))) {
ext2fs_mark_block_bitmap(fs->block_map, blk);
if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap(meta_bmap, blk))
ext2fs_mark_block_bitmap(rfs->move_blocks,
blk);
}
/*
* The inode table, if we need to relocate it, is
* handled specially. We have to reserve the blocks
* for both the old and the new inode table, since we
* can't have the inode table be destroyed during the
* block relocation phase.
*/
if (FS_INODE_TB(fs, i) == FS_INODE_TB(old_fs, i))
goto next_group; /* inode table not moved */
rfs->needed_blocks += fs->inode_blocks_per_group;
/*
* Mark the new inode table as in use in the new block
* allocation bitmap, and move any blocks that might
* be necessary.
*/
for (blk = fs->group_desc[i].bg_inode_table, j=0;
j < fs->inode_blocks_per_group ; j++, blk++) {
ext2fs_mark_block_bitmap(fs->block_map, blk);
if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap(meta_bmap, blk))
ext2fs_mark_block_bitmap(rfs->move_blocks,
blk);
}
/*
* Make sure the old inode table is reserved in the
* block reservation bitmap.
*/
for (blk = rfs->old_fs->group_desc[i].bg_inode_table, j=0;
j < fs->inode_blocks_per_group ; j++, blk++)
ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk);
next_group:
group_blk += rfs->new_fs->super->s_blocks_per_group;
}
retval = 0;
errout:
if (meta_bmap)
ext2fs_free_block_bitmap(meta_bmap);
return retval;
}
/*
* This helper function tries to allocate a new block. We try to
* avoid hitting the original group descriptor blocks at least at
* first, since we want to make it possible to recover from a badly
* aborted resize operation as much as possible.
*
* In the future, I may further modify this routine to balance out
* where we get the new blocks across the various block groups.
* Ideally we would allocate blocks that corresponded with the block
* group of the containing inode, and keep contiguous blocks
* together. However, this very difficult to do efficiently, since we
* don't have the necessary information up front.
*/
#define AVOID_OLD 1
#define DESPERATION 2
static void init_block_alloc(ext2_resize_t rfs)
{
rfs->alloc_state = AVOID_OLD;
rfs->new_blk = rfs->new_fs->super->s_first_data_block;
#if 0
/* HACK for testing */
if (rfs->new_fs->super->s_blocks_count >
rfs->old_fs->super->s_blocks_count)
rfs->new_blk = rfs->old_fs->super->s_blocks_count;
#endif
}
static blk_t get_new_block(ext2_resize_t rfs)
{
ext2_filsys fs = rfs->new_fs;
while (1) {
if (rfs->new_blk >= fs->super->s_blocks_count) {
if (rfs->alloc_state == DESPERATION)
return 0;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_BMOVE)
printf("Going into desperation "
"mode for block allocations\n");
#endif
rfs->alloc_state = DESPERATION;
rfs->new_blk = fs->super->s_first_data_block;
continue;
}
if (ext2fs_test_block_bitmap(fs->block_map, rfs->new_blk) ||
ext2fs_test_block_bitmap(rfs->reserve_blocks,
rfs->new_blk) ||
((rfs->alloc_state == AVOID_OLD) &&
(rfs->new_blk < rfs->old_fs->super->s_blocks_count) &&
ext2fs_test_block_bitmap(rfs->old_fs->block_map,
rfs->new_blk))) {
rfs->new_blk++;
continue;
}
return rfs->new_blk;
}
}
static errcode_t block_mover(ext2_resize_t rfs)
{
blk_t blk, old_blk, new_blk;
ext2_filsys fs = rfs->new_fs;
ext2_filsys old_fs = rfs->old_fs;
errcode_t retval;
int size, c;
int to_move, moved;
new_blk = fs->super->s_first_data_block;
if (!rfs->itable_buf) {
retval = ext2fs_get_mem(fs->blocksize *
fs->inode_blocks_per_group,
(void **) &rfs->itable_buf);
if (retval)
return retval;
}
retval = ext2fs_create_extent_table(&rfs->bmap, 0);
if (retval)
return retval;
/*
* The first step is to figure out where all of the blocks
* will go.
*/
to_move = moved = 0;
init_block_alloc(rfs);
for (blk = old_fs->super->s_first_data_block;
blk < old_fs->super->s_blocks_count; blk++) {
if (!ext2fs_test_block_bitmap(old_fs->block_map, blk))
continue;
if (!ext2fs_test_block_bitmap(rfs->move_blocks, blk))
continue;
new_blk = get_new_block(rfs);
if (!new_blk) {
retval = ENOSPC;
goto errout;
}
ext2fs_mark_block_bitmap(fs->block_map, new_blk);
ext2fs_add_extent_entry(rfs->bmap, blk, new_blk);
to_move++;
}
if (to_move == 0) {
retval = 0;
goto errout;
}
/*
* Step two is to actually move the blocks
*/
retval = ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
if (retval) goto errout;
if (rfs->progress) {
retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
0, to_move);
if (retval)
goto errout;
}
while (1) {
retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
if (retval) goto errout;
if (!size)
break;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_BMOVE)
printf("Moving %d blocks %u->%u\n", size,
old_blk, new_blk);
#endif
do {
c = size;
if (c > fs->inode_blocks_per_group)
c = fs->inode_blocks_per_group;
retval = io_channel_read_blk(fs->io, old_blk, c,
rfs->itable_buf);
if (retval) goto errout;
retval = io_channel_write_blk(fs->io, new_blk, c,
rfs->itable_buf);
if (retval) goto errout;
size -= c;
new_blk += c;
old_blk += c;
moved += c;
if (rfs->progress) {
io_channel_flush(fs->io);
retval = (rfs->progress)(rfs,
E2_RSZ_BLOCK_RELOC_PASS,
moved, to_move);
if (retval)
goto errout;
}
} while (size > 0);
io_channel_flush(fs->io);
}
errout:
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 3
*
* --------------------------------------------------------------------
*/
struct process_block_struct {
ext2_resize_t rfs;
ino_t ino;
struct ext2_inode * inode;
errcode_t error;
int is_dir;
int changed;
};
static int process_block(ext2_filsys fs, blk_t *block_nr,
e2_blkcnt_t blockcnt, blk_t ref_block,
int ref_offset, void *priv_data)
{
struct process_block_struct *pb;
errcode_t retval;
blk_t block, new_block;
int ret = 0;
pb = (struct process_block_struct *) priv_data;
block = *block_nr;
if (pb->rfs->bmap) {
new_block = ext2fs_extent_translate(pb->rfs->bmap, block);
if (new_block) {
*block_nr = new_block;
ret |= BLOCK_CHANGED;
pb->changed = 1;
#ifdef RESIZE2FS_DEBUG
if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
printf("ino=%ld, blockcnt=%ld, %u->%u\n",
pb->ino, blockcnt, block, new_block);
#endif
block = new_block;
}
}
if (pb->is_dir) {
retval = ext2fs_add_dir_block(fs->dblist, pb->ino,
block, (int) blockcnt);
if (retval) {
pb->error = retval;
ret |= BLOCK_ABORT;
}
}
return ret;
}
/*
* Progress callback
*/
static errcode_t progress_callback(ext2_filsys fs, ext2_inode_scan scan,
dgrp_t group, void * priv_data)
{
ext2_resize_t rfs = (ext2_resize_t) priv_data;
errcode_t retval;
/*
* This check is to protect against old ext2 libraries. It
* shouldn't be needed against new libraries.
*/
if ((group+1) == 0)
return 0;
if (rfs->progress) {
io_channel_flush(fs->io);
retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
group+1, fs->group_desc_count);
if (retval)
return retval;
}
return 0;
}
static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
{
struct process_block_struct pb;
ino_t ino, new_inode;
struct ext2_inode inode;
ext2_inode_scan scan = NULL;
errcode_t retval;
int group;
char *block_buf = 0;
ino_t start_to_move;
blk_t orig_size;
if ((rfs->old_fs->group_desc_count <=
rfs->new_fs->group_desc_count) &&
!rfs->bmap)
return 0;
/*
* Save the original size of the old filesystem, and
* temporarily set the size to be the new size if the new size
* is larger. We need to do this to avoid catching an error
* by the block iterator routines
*/
orig_size = rfs->old_fs->super->s_blocks_count;
if (orig_size < rfs->new_fs->super->s_blocks_count)
rfs->old_fs->super->s_blocks_count =
rfs->new_fs->super->s_blocks_count;
retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
if (retval) goto errout;
retval = ext2fs_init_dblist(rfs->old_fs, 0);
if (retval) goto errout;
retval = ext2fs_get_mem(rfs->old_fs->blocksize * 3,
(void **) &block_buf);
if (retval) goto errout;
start_to_move = (rfs->new_fs->group_desc_count *
rfs->new_fs->super->s_inodes_per_group);
if (rfs->progress) {
retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
0, rfs->old_fs->group_desc_count);
if (retval)
goto errout;
}
ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
pb.rfs = rfs;
pb.inode = &inode;
pb.error = 0;
new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
/*
* First, copy all of the inodes that need to be moved
* elsewhere in the inode table
*/
while (1) {
retval = ext2fs_get_next_inode(scan, &ino, &inode);
if (retval) goto errout;
if (!ino)
break;
if (inode.i_links_count == 0)
continue; /* inode not in use */
pb.is_dir = LINUX_S_ISDIR(inode.i_mode);
pb.changed = 0;
if (ext2fs_inode_has_valid_blocks(&inode) &&
(rfs->bmap || pb.is_dir)) {
pb.ino = ino;
retval = ext2fs_block_iterate2(rfs->old_fs,
ino, 0, block_buf,
process_block, &pb);
if (retval)
goto errout;
if (pb.error) {
retval = pb.error;
goto errout;
}
}
if (ino <= start_to_move)
continue; /* Don't need to move it. */
/*
* Find a new inode
*/
while (1) {
if (!ext2fs_test_inode_bitmap(rfs->new_fs->inode_map,
new_inode))
break;
new_inode++;
if (new_inode > rfs->new_fs->super->s_inodes_count) {
retval = ENOSPC;
goto errout;
}
}
ext2fs_mark_inode_bitmap(rfs->new_fs->inode_map, new_inode);
if (pb.changed) {
/* Get the new version of the inode */
retval = ext2fs_read_inode(rfs->old_fs, ino, &inode);
if (retval) goto errout;
}
retval = ext2fs_write_inode(rfs->old_fs, new_inode, &inode);
if (retval) goto errout;
group = (new_inode-1) / EXT2_INODES_PER_GROUP(rfs->new_fs->super);
if (LINUX_S_ISDIR(inode.i_mode))
rfs->new_fs->group_desc[group].bg_used_dirs_count++;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_INODEMAP)
printf("Inode moved %ld->%ld\n", ino, new_inode);
#endif
if (!rfs->imap) {
retval = ext2fs_create_extent_table(&rfs->imap, 0);
if (retval)
goto errout;
}
ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
}
io_channel_flush(rfs->old_fs->io);
errout:
rfs->old_fs->super->s_blocks_count = orig_size;
if (rfs->bmap) {
ext2fs_free_extent_table(rfs->bmap);
rfs->bmap = 0;
}
if (scan)
ext2fs_close_inode_scan(scan);
if (block_buf)
ext2fs_free_mem((void **) &block_buf);
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 4.
*
* --------------------------------------------------------------------
*/
struct istruct {
ext2_resize_t rfs;
errcode_t err;
unsigned long max_dirs;
int num;
};
static int check_and_change_inodes(ino_t dir, int entry,
struct ext2_dir_entry *dirent, int offset,
int blocksize, char *buf, void *priv_data)
{
struct istruct *is = (struct istruct *) priv_data;
ino_t new_inode;
if (is->rfs->progress && offset == 0) {
io_channel_flush(is->rfs->old_fs->io);
is->err = (is->rfs->progress)(is->rfs,
E2_RSZ_INODE_REF_UPD_PASS,
++is->num, is->max_dirs);
if (is->err)
return DIRENT_ABORT;
}
if (!dirent->inode)
return 0;
new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
if (!new_inode)
return 0;
#ifdef RESIZE2FS_DEBUG
if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
printf("Inode translate (dir=%ld, name=%.*s, %u->%ld)\n",
dir, dirent->name_len, dirent->name,
dirent->inode, new_inode);
#endif
dirent->inode = new_inode;
return DIRENT_CHANGED;
}
static errcode_t inode_ref_fix(ext2_resize_t rfs)
{
errcode_t retval;
struct istruct is;
if (!rfs->imap)
return 0;
/*
* Now, we iterate over all of the directories to update the
* inode references
*/
is.num = 0;
is.max_dirs = ext2fs_dblist_count(rfs->old_fs->dblist);
is.rfs = rfs;
is.err = 0;
if (rfs->progress) {
retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
0, is.max_dirs);
if (retval)
goto errout;
}
retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
DIRENT_FLAG_INCLUDE_EMPTY, 0,
check_and_change_inodes, &is);
if (retval)
goto errout;
if (is.err) {
retval = is.err;
goto errout;
}
errout:
ext2fs_free_extent_table(rfs->imap);
rfs->imap = 0;
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 5.
*
* In this phase we actually move the inode table around, and then
* update the summary statistics. This is scary, since aborting here
* will potentially scramble the filesystem. (We are moving the
* inode tables around in place, and so the potential for lost data,
* or at the very least scrambling the mapping between filenames and
* inode numbers is very high in case of a power failure here.)
* --------------------------------------------------------------------
*/
/*
* A very scary routine --- this one moves the inode table around!!!
*
* After this you have to use the rfs->new_fs file handle to read and
* write inodes.
*/
static errcode_t move_itables(ext2_resize_t rfs)
{
int i, n, num, max_groups, size, diff;
ext2_filsys fs = rfs->new_fs;
char *cp;
blk_t old_blk, new_blk;
errcode_t retval;
int to_move, moved;
max_groups = fs->group_desc_count;
if (max_groups > rfs->old_fs->group_desc_count)
max_groups = rfs->old_fs->group_desc_count;
size = fs->blocksize * fs->inode_blocks_per_group;
if (!rfs->itable_buf) {
retval = ext2fs_get_mem(size, (void **) &rfs->itable_buf);
if (retval)
return retval;
}
/*
* Figure out how many inode tables we need to move
*/
to_move = moved = 0;
for (i=0; i < max_groups; i++)
if (rfs->old_fs->group_desc[i].bg_inode_table !=
fs->group_desc[i].bg_inode_table)
to_move++;
if (to_move == 0)
return 0;
if (rfs->progress) {
retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
0, to_move);
if (retval)
goto errout;
}
rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
for (i=0; i < max_groups; i++) {
old_blk = rfs->old_fs->group_desc[i].bg_inode_table;
new_blk = fs->group_desc[i].bg_inode_table;
diff = new_blk - old_blk;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
printf("Itable move group %d block "
"%u->%u (diff %d)\n",
i, old_blk, new_blk, diff);
#endif
if (!diff)
continue;
retval = io_channel_read_blk(fs->io, old_blk,
fs->inode_blocks_per_group,
rfs->itable_buf);
if (retval)
goto errout;
/*
* The end of the inode table segment often contains
* all zeros, and we're often only moving the inode
* table down a block or two. If so, we can optimize
* things by not rewriting blocks that we know to be zero
* already.
*/
for (cp = rfs->itable_buf+size, n=0; n < size; n++, cp--)
if (*cp)
break;
n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
printf("%d blocks of zeros...\n", n);
#endif
num = fs->inode_blocks_per_group;
if (n > diff)
num -= n;
retval = io_channel_write_blk(fs->io, new_blk,
num, rfs->itable_buf);
if (retval) {
io_channel_write_blk(fs->io, old_blk,
num, rfs->itable_buf);
goto errout;
}
if (n > diff) {
retval = io_channel_write_blk(fs->io,
old_blk + fs->inode_blocks_per_group,
diff, (rfs->itable_buf +
(fs->inode_blocks_per_group - diff) *
fs->blocksize));
if (retval)
goto errout;
}
rfs->old_fs->group_desc[i].bg_inode_table = new_blk;
ext2fs_mark_super_dirty(rfs->old_fs);
if (rfs->progress) {
ext2fs_flush(rfs->old_fs);
retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
++moved, to_move);
if (retval)
goto errout;
}
}
ext2fs_flush(fs);
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
printf("Inode table move finished.\n");
#endif
return 0;
errout:
return retval;
}
/*
* Finally, recalculate the summary information
*/
static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
{
blk_t blk;
ino_t ino;
int group = 0;
int count = 0;
int total_free = 0;
int group_free = 0;
/*
* First calculate the block statistics
*/
for (blk = fs->super->s_first_data_block;
blk < fs->super->s_blocks_count; blk++) {
if (!ext2fs_fast_test_block_bitmap(fs->block_map, blk)) {
group_free++;
total_free++;
}
count++;
if ((count == fs->super->s_blocks_per_group) ||
(blk == fs->super->s_blocks_count-1)) {
fs->group_desc[group++].bg_free_blocks_count =
group_free;
count = 0;
group_free = 0;
}
}
fs->super->s_free_blocks_count = total_free;
/*
* Next, calculate the inode statistics
*/
group_free = 0;
total_free = 0;
count = 0;
group = 0;
for (ino = 1; ino <= fs->super->s_inodes_count; ino++) {
if (!ext2fs_fast_test_inode_bitmap(fs->inode_map, ino)) {
group_free++;
total_free++;
}
count++;
if ((count == fs->super->s_inodes_per_group) ||
(ino == fs->super->s_inodes_count)) {
fs->group_desc[group++].bg_free_inodes_count =
group_free;
count = 0;
group_free = 0;
}
}
fs->super->s_free_inodes_count = total_free;
ext2fs_mark_super_dirty(fs);
return 0;
}
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