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gerrit-public.fairphone.software / platform / external / e2fsprogs / abbf95c739cfad7990a67ce73d01f4b6626cb5fc / . / resize / resize2fs.c
blob: 5f9f16b1e3f2d9505683d4b6ffab7a36625297d6 [file] [log] [blame]
/*
* resize2fs.c --- ext2 main routine
*
* Copyright (C) 1997, 1998 by Theodore Ts'o and
* PowerQuest, Inc.
*
* Copyright (C) 1999, 2000 by Theosore Ts'o
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %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 "config.h"
#include "resize2fs.h"
#include <time.h>
#ifdef __linux__ /* Kludge for debugging */
#define RESIZE2FS_DEBUG
#endif
static void fix_uninit_block_bitmaps(ext2_filsys fs);
static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_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 fix_resize_inode(ext2_filsys fs);
static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
static errcode_t fix_sb_journal_backup(ext2_filsys fs);
static errcode_t mark_table_blocks(ext2_filsys fs,
ext2fs_block_bitmap bmap);
/*
* Some helper CPP macros
*/
#define IS_BLOCK_BM(fs, i, blk) ((blk) == ext2fs_block_bitmap_loc((fs),(i)))
#define IS_INODE_BM(fs, i, blk) ((blk) == ext2fs_inode_bitmap_loc((fs),(i)))
#define IS_INODE_TB(fs, i, blk) (((blk) >= ext2fs_inode_table_loc((fs), (i))) && \
((blk) < (ext2fs_inode_table_loc((fs), (i)) + \
(fs)->inode_blocks_per_group)))
/* Some bigalloc helper macros which are more succint... */
#define B2C(x) EXT2FS_B2C(fs, (x))
#define C2B(x) EXT2FS_C2B(fs, (x))
#define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
#define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
#define LT_CLSTR(x, y) (B2C(x) < B2C(y))
#define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
#define GT_CLSTR(x, y) (B2C(x) > B2C(y))
static int lazy_itable_init;
/*
* This is the top-level routine which does the dirty deed....
*/
errcode_t resize_fs(ext2_filsys fs, blk64_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;
struct resource_track rtrack, overall_track;
/*
* Create the data structure
*/
retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
if (retval)
return retval;
memset(rfs, 0, sizeof(struct ext2_resize_struct));
fs->priv_data = rfs;
rfs->old_fs = fs;
rfs->flags = flags;
rfs->itable_buf = 0;
rfs->progress = progress;
init_resource_track(&overall_track, "overall resize2fs", fs->io);
init_resource_track(&rtrack, "read_bitmaps", fs->io);
retval = ext2fs_read_bitmaps(fs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
fs->super->s_state |= EXT2_ERROR_FS;
ext2fs_mark_super_dirty(fs);
ext2fs_flush(fs);
init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
fix_uninit_block_bitmaps(fs);
print_resource_track(rfs, &rtrack, fs->io);
retval = ext2fs_dup_handle(fs, &rfs->new_fs);
if (retval)
goto errout;
init_resource_track(&rtrack, "adjust_superblock", fs->io);
retval = adjust_superblock(rfs, *new_size);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
fix_uninit_block_bitmaps(rfs->new_fs);
print_resource_track(rfs, &rtrack, fs->io);
/* Clear the block bitmap uninit flag for the last block group */
ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
EXT2_BG_BLOCK_UNINIT);
*new_size = ext2fs_blocks_count(rfs->new_fs->super);
init_resource_track(&rtrack, "blocks_to_move", fs->io);
retval = blocks_to_move(rfs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_BMOVE)
printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
ext2fs_free_blocks_count(rfs->old_fs->super),
ext2fs_free_blocks_count(rfs->new_fs->super),
rfs->needed_blocks);
#endif
init_resource_track(&rtrack, "block_mover", fs->io);
retval = block_mover(rfs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
retval = inode_scan_and_fix(rfs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "inode_ref_fix", fs->io);
retval = inode_ref_fix(rfs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "move_itables", fs->io);
retval = move_itables(rfs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
retval = ext2fs_calculate_summary_stats(rfs->new_fs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "fix_resize_inode", fs->io);
retval = fix_resize_inode(rfs->new_fs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
retval = fix_sb_journal_backup(rfs->new_fs);
if (retval)
goto errout;
print_resource_track(rfs, &rtrack, fs->io);
rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
print_resource_track(rfs, &overall_track, fs->io);
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(&rfs->itable_buf);
if (rfs->reserve_blocks)
ext2fs_free_block_bitmap(rfs->reserve_blocks);
if (rfs->move_blocks)
ext2fs_free_block_bitmap(rfs->move_blocks);
ext2fs_free_mem(&rfs);
return 0;
errout:
if (rfs->new_fs)
ext2fs_free(rfs->new_fs);
if (rfs->itable_buf)
ext2fs_free_mem(&rfs->itable_buf);
ext2fs_free_mem(&rfs);
return retval;
}
/*
* Clean up the bitmaps for unitialized bitmaps
*/
static void fix_uninit_block_bitmaps(ext2_filsys fs)
{
blk64_t blk, lblk;
dgrp_t g;
int i;
if (!ext2fs_has_group_desc_csum(fs))
return;
for (g=0; g < fs->group_desc_count; g++) {
if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
continue;
blk = ext2fs_group_first_block2(fs, g);
lblk = ext2fs_group_last_block2(fs, g);
ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
lblk - blk + 1);
ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
ext2fs_mark_block_bitmap2(fs->block_map,
ext2fs_block_bitmap_loc(fs, g));
ext2fs_mark_block_bitmap2(fs->block_map,
ext2fs_inode_bitmap_loc(fs, g));
for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
i < (unsigned int) fs->inode_blocks_per_group;
i++, blk++)
ext2fs_mark_block_bitmap2(fs->block_map, blk);
}
}
/* --------------------------------------------------------------------
*
* 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.
* --------------------------------------------------------------------
*/
/*
* If the group descriptor's bitmap and inode table blocks are valid,
* release them in the new filesystem data structure, and mark them as
* reserved so the old inode table blocks don't get overwritten.
*/
static void free_gdp_blocks(ext2_filsys fs,
ext2fs_block_bitmap reserve_blocks,
ext2_filsys old_fs,
dgrp_t group)
{
blk64_t blk;
int j;
blk = ext2fs_block_bitmap_loc(old_fs, group);
if (blk &&
(blk < ext2fs_blocks_count(fs->super))) {
ext2fs_block_alloc_stats2(fs, blk, -1);
ext2fs_mark_block_bitmap2(reserve_blocks, blk);
}
blk = ext2fs_inode_bitmap_loc(old_fs, group);
if (blk &&
(blk < ext2fs_blocks_count(fs->super))) {
ext2fs_block_alloc_stats2(fs, blk, -1);
ext2fs_mark_block_bitmap2(reserve_blocks, blk);
}
blk = ext2fs_inode_table_loc(old_fs, group);
if (blk == 0 ||
(blk >= ext2fs_blocks_count(fs->super)))
return;
for (j = 0;
j < fs->inode_blocks_per_group; j++, blk++) {
if (blk >= ext2fs_blocks_count(fs->super))
break;
ext2fs_block_alloc_stats2(fs, blk, -1);
ext2fs_mark_block_bitmap2(reserve_blocks, blk);
}
}
/*
* This routine is shared by the online and offline resize routines.
* All of the information which is adjusted in memory is done here.
*/
errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
{
errcode_t retval;
blk64_t overhead = 0;
blk64_t rem;
blk64_t blk, group_block;
blk64_t real_end;
blk64_t old_numblocks, numblocks, adjblocks;
unsigned long i, j, old_desc_blocks;
unsigned int meta_bg, meta_bg_size;
int has_super, csum_flag;
unsigned long long new_inodes; /* u64 to check for overflow */
double percent;
ext2fs_blocks_count_set(fs->super, new_size);
retry:
fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
fs->super->s_first_data_block,
EXT2_BLOCKS_PER_GROUP(fs->super));
if (fs->group_desc_count == 0)
return EXT2_ET_TOOSMALL;
fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
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.
*/
overhead = (int) (2 + fs->inode_blocks_per_group);
if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
overhead += 1 + fs->desc_blocks +
fs->super->s_reserved_gdt_blocks;
/*
* See if the last group is big enough to support the
* necessary data structures. If not, we need to get rid of
* it.
*/
rem = (ext2fs_blocks_count(fs->super) - 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 ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
ext2fs_blocks_count_set(fs->super,
ext2fs_blocks_count(fs->super) - rem);
goto retry;
}
/*
* Adjust the number of inodes
*/
new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
if (new_inodes > ~0U) {
fprintf(stderr, _("inodes (%llu) must be less than %u"),
new_inodes, ~0U);
return EXT2_ET_TOO_MANY_INODES;
}
fs->super->s_inodes_count = fs->super->s_inodes_per_group *
fs->group_desc_count;
/*
* Adjust the number of free blocks
*/
blk = ext2fs_blocks_count(old_fs->super);
if (blk > ext2fs_blocks_count(fs->super))
ext2fs_free_blocks_count_set(fs->super,
ext2fs_free_blocks_count(fs->super) -
(blk - ext2fs_blocks_count(fs->super)));
else
ext2fs_free_blocks_count_set(fs->super,
ext2fs_free_blocks_count(fs->super) +
(ext2fs_blocks_count(fs->super) - blk));
/*
* Adjust the number of reserved blocks
*/
percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
ext2fs_blocks_count(old_fs->super);
ext2fs_r_blocks_count_set(fs->super,
(percent * ext2fs_blocks_count(fs->super) /
100.0));
/*
* Adjust the bitmaps for size
*/
retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
fs->super->s_inodes_count,
fs->inode_map);
if (retval) goto errout;
real_end = (((blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super) *
fs->group_desc_count)) - 1 +
fs->super->s_first_data_block;
retval = ext2fs_resize_block_bitmap2(new_size - 1,
real_end, fs->block_map);
if (retval) goto errout;
/*
* If we are growing the file system, also grow the size of
* the reserve_blocks bitmap
*/
if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
retval = ext2fs_resize_block_bitmap2(new_size - 1,
real_end, reserve_blocks);
if (retval) goto errout;
}
/*
* Reallocate the group descriptors as necessary.
*/
if (old_fs->desc_blocks != fs->desc_blocks) {
retval = ext2fs_resize_mem(old_fs->desc_blocks *
fs->blocksize,
fs->desc_blocks * fs->blocksize,
&fs->group_desc);
if (retval)
goto errout;
if (fs->desc_blocks > old_fs->desc_blocks)
memset((char *) fs->group_desc +
(old_fs->desc_blocks * fs->blocksize), 0,
(fs->desc_blocks - old_fs->desc_blocks) *
fs->blocksize);
}
/*
* If the resize_inode feature is set, and we are changing the
* number of descriptor blocks, then adjust
* s_reserved_gdt_blocks if possible to avoid needing to move
* the inode table either now or in the future.
*/
if ((fs->super->s_feature_compat &
EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
(old_fs->desc_blocks != fs->desc_blocks)) {
int new;
new = ((int) fs->super->s_reserved_gdt_blocks) +
(old_fs->desc_blocks - fs->desc_blocks);
if (new < 0)
new = 0;
if (new > (int) fs->blocksize/4)
new = fs->blocksize/4;
fs->super->s_reserved_gdt_blocks = new;
}
/*
* If we are shrinking the number of block groups, we're done
* and can exit now.
*/
if (old_fs->group_desc_count > fs->group_desc_count) {
/*
* Check the block groups that we are chopping off
* and free any blocks associated with their metadata
*/
for (i = fs->group_desc_count;
i < old_fs->group_desc_count; i++)
free_gdp_blocks(fs, reserve_blocks, old_fs, i);
retval = 0;
goto errout;
}
/*
* Fix the count of the last (old) block group
*/
old_numblocks = (ext2fs_blocks_count(old_fs->super) -
old_fs->super->s_first_data_block) %
old_fs->super->s_blocks_per_group;
if (!old_numblocks)
old_numblocks = old_fs->super->s_blocks_per_group;
if (old_fs->group_desc_count == fs->group_desc_count) {
numblocks = (ext2fs_blocks_count(fs->super) -
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;
i = old_fs->group_desc_count - 1;
ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
ext2fs_group_desc_csum_set(fs, i);
/*
* 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 (old_fs->group_desc_count >= fs->group_desc_count) {
retval = 0;
goto errout;
}
/*
* Initialize the new block group descriptors
*/
group_block = ext2fs_group_first_block2(fs,
old_fs->group_desc_count);
csum_flag = ext2fs_has_group_desc_csum(fs);
if (access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0)
lazy_itable_init = 1;
if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
old_desc_blocks = fs->super->s_first_meta_bg;
else
old_desc_blocks = fs->desc_blocks +
fs->super->s_reserved_gdt_blocks;
/*
* If we changed the number of block_group descriptor blocks,
* we need to make sure they are all marked as reserved in the
* file systems's block allocation map.
*/
for (i = 0; i < old_fs->group_desc_count; i++)
ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
for (i = old_fs->group_desc_count;
i < fs->group_desc_count; i++) {
memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
sizeof(struct ext2_group_desc));
adjblocks = 0;
ext2fs_bg_flags_zap(fs, i);
if (csum_flag) {
ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
if (!lazy_itable_init)
ext2fs_bg_flags_set(fs, i,
EXT2_BG_INODE_ZEROED);
ext2fs_bg_itable_unused_set(fs, i,
fs->super->s_inodes_per_group);
}
numblocks = ext2fs_group_blocks_count(fs, i);
if ((i < fs->group_desc_count - 1) && csum_flag)
ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
has_super = ext2fs_bg_has_super(fs, i);
if (has_super) {
ext2fs_block_alloc_stats2(fs, group_block, +1);
adjblocks++;
}
meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
meta_bg = i / meta_bg_size;
if (!(fs->super->s_feature_incompat &
EXT2_FEATURE_INCOMPAT_META_BG) ||
(meta_bg < fs->super->s_first_meta_bg)) {
if (has_super) {
for (j=0; j < old_desc_blocks; j++)
ext2fs_block_alloc_stats2(fs,
group_block + 1 + j, +1);
adjblocks += old_desc_blocks;
}
} else {
if (has_super)
has_super = 1;
if (((i % meta_bg_size) == 0) ||
((i % meta_bg_size) == 1) ||
((i % meta_bg_size) == (meta_bg_size-1)))
ext2fs_block_alloc_stats2(fs,
group_block + has_super, +1);
}
adjblocks += 2 + fs->inode_blocks_per_group;
numblocks -= adjblocks;
ext2fs_free_blocks_count_set(fs->super,
ext2fs_free_blocks_count(fs->super) - adjblocks);
fs->super->s_free_inodes_count +=
fs->super->s_inodes_per_group;
ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
ext2fs_bg_free_inodes_count_set(fs, i,
fs->super->s_inodes_per_group);
ext2fs_bg_used_dirs_count_set(fs, i, 0);
ext2fs_group_desc_csum_set(fs, i);
retval = ext2fs_allocate_group_table(fs, i, 0);
if (retval) goto errout;
group_block += fs->super->s_blocks_per_group;
}
retval = 0;
/*
* Mark all of the metadata blocks as reserved so they won't
* get allocated by the call to ext2fs_allocate_group_table()
* in blocks_to_move(), where we allocate new blocks to
* replace those allocation bitmap and inode table blocks
* which have to get relocated to make space for an increased
* number of the block group descriptors.
*/
if (reserve_blocks)
mark_table_blocks(fs, reserve_blocks);
errout:
return (retval);
}
/*
* This routine adjusts the superblock and other data structures, both
* in disk as well as in memory...
*/
static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
{
ext2_filsys fs;
int adj = 0;
errcode_t retval;
blk64_t group_block;
unsigned long i;
unsigned long max_group;
fs = rfs->new_fs;
ext2fs_mark_super_dirty(fs);
ext2fs_mark_bb_dirty(fs);
ext2fs_mark_ib_dirty(fs);
retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
&rfs->reserve_blocks);
if (retval)
return retval;
retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
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;
}
/*
* 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;
}
/*
* If we are using uninit_bg (aka GDT_CSUM) and the kernel
* supports lazy inode initialization, we can skip
* initializing the inode table.
*/
if (lazy_itable_init && ext2fs_has_group_desc_csum(fs)) {
retval = 0;
goto errout;
}
/*
* Initialize the inode table
*/
retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
&rfs->itable_buf);
if (retval)
goto errout;
memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
group_block = ext2fs_group_first_block2(fs,
rfs->old_fs->group_desc_count);
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++) {
/*
* Write out the new inode table
*/
retval = io_channel_write_blk64(fs->io,
ext2fs_inode_table_loc(fs, i),
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 bmap)
{
dgrp_t i;
blk64_t blk;
for (i = 0; i < fs->group_desc_count; i++) {
ext2fs_reserve_super_and_bgd(fs, i, bmap);
/*
* Mark the blocks used for the inode table
*/
blk = ext2fs_inode_table_loc(fs, i);
if (blk)
ext2fs_mark_block_bitmap_range2(bmap, blk,
fs->inode_blocks_per_group);
/*
* Mark block used for the block bitmap
*/
blk = ext2fs_block_bitmap_loc(fs, i);
if (blk)
ext2fs_mark_block_bitmap2(bmap, blk);
/*
* Mark block used for the inode bitmap
*/
blk = ext2fs_inode_bitmap_loc(fs, i);
if (blk)
ext2fs_mark_block_bitmap2(bmap, blk);
}
return 0;
}
/*
* This function checks to see if a particular block (either a
* superblock or a block group descriptor) overlaps with an inode or
* block bitmap block, or with the inode table.
*/
static void mark_fs_metablock(ext2_resize_t rfs,
ext2fs_block_bitmap meta_bmap,
int group, blk64_t blk)
{
ext2_filsys fs = rfs->new_fs;
ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
ext2fs_block_alloc_stats2(fs, blk, +1);
/*
* 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, group, blk)) {
ext2fs_block_bitmap_loc_set(fs, group, 0);
rfs->needed_blocks++;
return;
}
if (IS_INODE_BM(fs, group, blk)) {
ext2fs_inode_bitmap_loc_set(fs, group, 0);
rfs->needed_blocks++;
return;
}
if (IS_INODE_TB(fs, group, blk)) {
ext2fs_inode_table_loc_set(fs, group, 0);
rfs->needed_blocks++;
return;
}
if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
dgrp_t i;
for (i=0; i < rfs->old_fs->group_desc_count; i++) {
if (IS_BLOCK_BM(fs, i, blk)) {
ext2fs_block_bitmap_loc_set(fs, i, 0);
rfs->needed_blocks++;
return;
}
if (IS_INODE_BM(fs, i, blk)) {
ext2fs_inode_bitmap_loc_set(fs, i, 0);
rfs->needed_blocks++;
return;
}
if (IS_INODE_TB(fs, i, blk)) {
ext2fs_inode_table_loc_set(fs, i, 0);
rfs->needed_blocks++;
return;
}
}
}
if (ext2fs_has_group_desc_csum(fs) &&
(ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
/*
* If the block bitmap is uninitialized, which means
* nothing other than standard metadata in use.
*/
return;
} else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap2(meta_bmap, blk)) {
ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
rfs->needed_blocks++;
}
}
/*
* 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 j, has_super;
dgrp_t i, max_groups, g;
blk64_t blk, group_blk;
blk64_t old_blocks, new_blocks;
blk64_t new_size;
unsigned int meta_bg, meta_bg_size;
errcode_t retval;
ext2_filsys fs, old_fs;
ext2fs_block_bitmap meta_bmap;
int flex_bg;
fs = rfs->new_fs;
old_fs = rfs->old_fs;
if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
fs = rfs->old_fs;
retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
&rfs->move_blocks);
if (retval)
return retval;
retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
&meta_bmap);
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 any
* group's metadata blocks (either allocation bitmaps or the
* inode table) which are beyond the end of the new
* filesystem.
*/
new_size = ext2fs_blocks_count(fs->super);
if (new_size < ext2fs_blocks_count(old_fs->super)) {
for (g = 0; g < fs->group_desc_count; g++) {
int realloc = 0;
/*
* ext2fs_allocate_group_table will re-allocate any
* metadata blocks whose location is set to zero.
*/
if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
ext2fs_block_bitmap_loc_set(fs, g, 0);
realloc = 1;
}
if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
ext2fs_inode_bitmap_loc_set(fs, g, 0);
realloc = 1;
}
if ((ext2fs_inode_table_loc(fs, g) +
fs->inode_blocks_per_group) > new_size) {
ext2fs_inode_table_loc_set(fs, g, 0);
realloc = 1;
}
if (realloc) {
retval = ext2fs_allocate_group_table(fs, g, 0);
if (retval)
return retval;
}
}
}
/*
* If we're shrinking the filesystem, we need to move all of
* the blocks that don't fit any more
*/
for (blk = ext2fs_blocks_count(fs->super);
blk < ext2fs_blocks_count(old_fs->super); blk++) {
g = ext2fs_group_of_blk2(fs, blk);
if (ext2fs_has_group_desc_csum(fs) &&
ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
/*
* The block bitmap is uninitialized, so skip
* to the next block group.
*/
blk = ext2fs_group_first_block2(fs, g+1) - 1;
continue;
}
if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap2(meta_bmap, blk)) {
ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
rfs->needed_blocks++;
}
ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
}
if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
old_blocks = old_fs->super->s_first_meta_bg;
new_blocks = fs->super->s_first_meta_bg;
} else {
old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_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_block_alloc_stats2(fs, blk, -1);
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....
*/
meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
flex_bg = fs->super->s_feature_incompat &
EXT4_FEATURE_INCOMPAT_FLEX_BG;
/* first reserve all of the existing fs meta blocks */
for (i = 0; i < max_groups; i++) {
has_super = ext2fs_bg_has_super(fs, i);
if (has_super)
mark_fs_metablock(rfs, meta_bmap, i, group_blk);
meta_bg = i / meta_bg_size;
if (!(fs->super->s_feature_incompat &
EXT2_FEATURE_INCOMPAT_META_BG) ||
(meta_bg < fs->super->s_first_meta_bg)) {
if (has_super) {
for (blk = group_blk+1;
blk < group_blk + 1 + new_blocks; blk++)
mark_fs_metablock(rfs, meta_bmap,
i, blk);
}
} else {
if (has_super)
has_super = 1;
if (((i % meta_bg_size) == 0) ||
((i % meta_bg_size) == 1) ||
((i % meta_bg_size) == (meta_bg_size-1)))
mark_fs_metablock(rfs, meta_bmap, i,
group_blk + has_super);
}
/*
* Reserve the existing meta blocks that we know
* aren't to be moved.
*
* For flex_bg file systems, in order to avoid
* overwriting fs metadata (especially inode table
* blocks) belonging to a different block group when
* we are relocating the inode tables, we need to
* reserve all existing fs metadata blocks.
*/
if (ext2fs_block_bitmap_loc(fs, i))
ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
ext2fs_block_bitmap_loc(fs, i));
else if (flex_bg && i < old_fs->group_desc_count)
ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
ext2fs_block_bitmap_loc(old_fs, i));
if (ext2fs_inode_bitmap_loc(fs, i))
ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
ext2fs_inode_bitmap_loc(fs, i));
else if (flex_bg && i < old_fs->group_desc_count)
ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
ext2fs_inode_bitmap_loc(old_fs, i));
if (ext2fs_inode_table_loc(fs, i))
ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
ext2fs_inode_table_loc(fs, i),
fs->inode_blocks_per_group);
else if (flex_bg && i < old_fs->group_desc_count)
ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
ext2fs_inode_table_loc(old_fs, i),
old_fs->inode_blocks_per_group);
group_blk += rfs->new_fs->super->s_blocks_per_group;
}
/* Allocate the missing data structures */
for (i = 0; i < max_groups; i++) {
if (ext2fs_inode_table_loc(fs, i) &&
ext2fs_inode_bitmap_loc(fs, i) &&
ext2fs_block_bitmap_loc(fs, i))
continue;
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 (ext2fs_block_bitmap_loc(old_fs, i) !=
(blk = ext2fs_block_bitmap_loc(fs, i))) {
ext2fs_block_alloc_stats2(fs, blk, +1);
if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap2(meta_bmap, blk))
ext2fs_mark_block_bitmap2(rfs->move_blocks,
blk);
}
if (ext2fs_inode_bitmap_loc(old_fs, i) !=
(blk = ext2fs_inode_bitmap_loc(fs, i))) {
ext2fs_block_alloc_stats2(fs, blk, +1);
if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap2(meta_bmap, blk))
ext2fs_mark_block_bitmap2(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 (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
continue; /* 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 = ext2fs_inode_table_loc(fs, i), j=0;
j < fs->inode_blocks_per_group ; j++, blk++) {
ext2fs_block_alloc_stats2(fs, blk, +1);
if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
!ext2fs_test_block_bitmap2(meta_bmap, blk))
ext2fs_mark_block_bitmap2(rfs->move_blocks,
blk);
}
/*
* Make sure the old inode table is reserved in the
* block reservation bitmap.
*/
for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
j < fs->inode_blocks_per_group ; j++, blk++)
ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
}
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 (ext2fs_blocks_count(rfs->new_fs->super) >
ext2fs_blocks_count(rfs->old_fs->super))
rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
#endif
}
static blk64_t get_new_block(ext2_resize_t rfs)
{
ext2_filsys fs = rfs->new_fs;
while (1) {
if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
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_bitmap2(fs->block_map, rfs->new_blk) ||
ext2fs_test_block_bitmap2(rfs->reserve_blocks,
rfs->new_blk) ||
((rfs->alloc_state == AVOID_OLD) &&
(rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
rfs->new_blk))) {
rfs->new_blk++;
continue;
}
return rfs->new_blk;
}
}
static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
blk64_t *ret)
{
ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
blk64_t blk;
blk = get_new_block(rfs);
if (!blk)
return ENOSPC;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & 0xF)
printf("get_alloc_block allocating %llu\n", blk);
#endif
ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
*ret = (blk64_t) blk;
return 0;
}
static errcode_t block_mover(ext2_resize_t rfs)
{
blk64_t blk, old_blk, new_blk;
ext2_filsys fs = rfs->new_fs;
ext2_filsys old_fs = rfs->old_fs;
errcode_t retval;
__u64 size;
int c;
int to_move, moved;
ext2_badblocks_list badblock_list = 0;
int bb_modified = 0;
fs->get_alloc_block = resize2fs_get_alloc_block;
old_fs->get_alloc_block = resize2fs_get_alloc_block;
retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
if (retval)
return retval;
new_blk = fs->super->s_first_data_block;
if (!rfs->itable_buf) {
retval = ext2fs_get_array(fs->blocksize,
fs->inode_blocks_per_group,
&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 = B2C(old_fs->super->s_first_data_block);
blk < ext2fs_blocks_count(old_fs->super);
blk += EXT2FS_CLUSTER_RATIO(fs)) {
if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
continue;
if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
continue;
if (ext2fs_badblocks_list_test(badblock_list, blk)) {
ext2fs_badblocks_list_del(badblock_list, blk);
bb_modified++;
continue;
}
new_blk = get_new_block(rfs);
if (!new_blk) {
retval = ENOSPC;
goto errout;
}
ext2fs_block_alloc_stats2(fs, new_blk, +1);
ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
to_move++;
}
if (to_move == 0) {
if (rfs->bmap) {
ext2fs_free_extent_table(rfs->bmap);
rfs->bmap = 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;
old_blk = C2B(old_blk);
new_blk = C2B(new_blk);
size = C2B(size);
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_BMOVE)
printf("Moving %llu blocks %llu->%llu\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_blk64(fs->io, old_blk, c,
rfs->itable_buf);
if (retval) goto errout;
retval = io_channel_write_blk64(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:
if (badblock_list) {
if (!retval && bb_modified)
retval = ext2fs_update_bb_inode(old_fs,
badblock_list);
ext2fs_badblocks_list_free(badblock_list);
}
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 3
*
* --------------------------------------------------------------------
*/
/*
* The extent translation table is stored in clusters so we need to
* take special care when mapping a source block number to its
* destination block number.
*/
static __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
{
__u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
if (new_block != 0)
new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
return new_block;
}
struct process_block_struct {
ext2_resize_t rfs;
ext2_ino_t ino;
ext2_ino_t old_ino;
struct ext2_inode * inode;
errcode_t error;
int is_dir;
int changed;
int has_extents;
};
static int process_block(ext2_filsys fs, blk64_t *block_nr,
e2_blkcnt_t blockcnt,
blk64_t ref_block EXT2FS_ATTR((unused)),
int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
{
struct process_block_struct *pb;
errcode_t retval;
blk64_t block, new_block;
int ret = 0;
pb = (struct process_block_struct *) priv_data;
block = *block_nr;
if (pb->rfs->bmap) {
new_block = extent_translate(fs, 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=%u, blockcnt=%lld, %llu->%llu\n",
pb->old_ino, blockcnt, block,
new_block);
#endif
block = new_block;
}
}
/*
* If we moved inodes and metadata_csum is enabled, we must force the
* extent block to be rewritten with new checksum.
*/
if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
pb->has_extents &&
pb->old_ino != pb->ino)
ret |= BLOCK_CHANGED;
if (pb->is_dir) {
retval = ext2fs_add_dir_block2(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 EXT2FS_ATTR((unused)),
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 migrate_ea_block(ext2_resize_t rfs, ext2_ino_t ino,
struct ext2_inode *inode, int *changed)
{
char *buf;
blk64_t new_block;
errcode_t err = 0;
/* No EA block or no remapping? Quit early. */
if (ext2fs_file_acl_block(rfs->old_fs, inode) == 0 && !rfs->bmap)
return 0;
new_block = extent_translate(rfs->old_fs, rfs->bmap,
ext2fs_file_acl_block(rfs->old_fs, inode));
if (new_block == 0)
return 0;
/* Set the new ACL block */
ext2fs_file_acl_block_set(rfs->old_fs, inode, new_block);
/* Update checksum */
if (EXT2_HAS_RO_COMPAT_FEATURE(rfs->new_fs->super,
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
err = ext2fs_get_mem(rfs->old_fs->blocksize, &buf);
if (err)
return err;
rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
err = ext2fs_read_ext_attr3(rfs->old_fs, new_block, buf, ino);
rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
if (err)
goto out;
err = ext2fs_write_ext_attr3(rfs->old_fs, new_block, buf, ino);
if (err)
goto out;
}
*changed = 1;
out:
ext2fs_free_mem(&buf);
return err;
}
static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
{
struct process_block_struct pb;
ext2_ino_t ino, new_inode;
struct ext2_inode *inode = NULL;
ext2_inode_scan scan = NULL;
errcode_t retval;
char *block_buf = 0;
ext2_ino_t start_to_move;
blk64_t orig_size;
int inode_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 = ext2fs_blocks_count(rfs->old_fs->super);
if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
ext2fs_blocks_count_set(rfs->old_fs->super,
ext2fs_blocks_count(rfs->new_fs->super));
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_array(rfs->old_fs->blocksize, 3, &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);
inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
inode = malloc(inode_size);
if (!inode) {
retval = ENOMEM;
goto errout;
}
/*
* First, copy all of the inodes that need to be moved
* elsewhere in the inode table
*/
while (1) {
retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
if (retval) goto errout;
if (!ino)
break;
if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
continue; /* inode not in use */
pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
pb.changed = 0;
/* Remap EA block */
retval = migrate_ea_block(rfs, ino, inode, &pb.changed);
if (retval)
goto errout;
new_inode = ino;
if (ino <= start_to_move)
goto remap_blocks; /* Don't need to move inode. */
/*
* Find a new inode. Now that extents and directory blocks
* are tied to the inode number through the checksum, we must
* set up the new inode before we start rewriting blocks.
*/
retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
if (retval)
goto errout;
ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
pb.is_dir);
inode->i_ctime = time(0);
retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
inode, inode_size);
if (retval)
goto errout;
pb.changed = 0;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_INODEMAP)
printf("Inode moved %u->%u\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);
remap_blocks:
if (pb.changed)
retval = ext2fs_write_inode_full(rfs->old_fs,
new_inode,
inode, inode_size);
if (retval)
goto errout;
/*
* Update inodes to point to new blocks; schedule directory
* blocks for inode remapping. Need to write out dir blocks
* with new inode numbers if we have metadata_csum enabled.
*/
if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
(rfs->bmap || pb.is_dir)) {
pb.ino = new_inode;
pb.old_ino = ino;
pb.has_extents = inode->i_flags & EXT4_EXTENTS_FL;
rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
retval = ext2fs_block_iterate3(rfs->old_fs,
new_inode, 0, block_buf,
process_block, &pb);
rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
if (retval)
goto errout;
if (pb.error) {
retval = pb.error;
goto errout;
}
}
}
io_channel_flush(rfs->old_fs->io);
errout:
ext2fs_blocks_count_set(rfs->old_fs->super, 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(&block_buf);
free(inode);
return retval;
}
/* --------------------------------------------------------------------
*
* Resize processing, phase 4.
*
* --------------------------------------------------------------------
*/
struct istruct {
ext2_resize_t rfs;
errcode_t err;
unsigned int max_dirs;
unsigned int num;
};
static int check_and_change_inodes(ext2_ino_t dir,
int entry EXT2FS_ATTR((unused)),
struct ext2_dir_entry *dirent, int offset,
int blocksize EXT2FS_ATTR((unused)),
char *buf EXT2FS_ATTR((unused)),
void *priv_data)
{
struct istruct *is = (struct istruct *) priv_data;
struct ext2_inode inode;
ext2_ino_t new_inode;
errcode_t retval;
int ret = 0;
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 we have checksums enabled and the inode wasn't present in the
* old fs, then we must rewrite all dir blocks with new checksums.
*/
if (EXT2_HAS_RO_COMPAT_FEATURE(is->rfs->old_fs->super,
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
!ext2fs_test_inode_bitmap2(is->rfs->old_fs->inode_map, dir))
ret |= DIRENT_CHANGED;
if (!dirent->inode)
return ret;
new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
if (!new_inode)
return ret;
#ifdef RESIZE2FS_DEBUG
if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
dir, ext2fs_dirent_name_len(dirent), dirent->name,
dirent->inode, new_inode);
#endif
dirent->inode = new_inode;
/* Update the directory mtime and ctime */
retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
if (retval == 0) {
inode.i_mtime = inode.i_ctime = time(0);
is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
if (is->err)
return ret | DIRENT_ABORT;
}
return ret | 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_count2(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;
}
rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
DIRENT_FLAG_INCLUDE_EMPTY, 0,
check_and_change_inodes, &is);
rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
if (retval)
goto errout;
if (is.err) {
retval = is.err;
goto errout;
}
if (rfs->progress && (is.num < is.max_dirs))
(rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
is.max_dirs, is.max_dirs);
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 n, num, size;
long long diff;
dgrp_t i, max_groups;
ext2_filsys fs = rfs->new_fs;
char *cp;
blk64_t old_blk, new_blk, blk;
errcode_t retval;
int j, 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, &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 (ext2fs_inode_table_loc(rfs->old_fs, i) !=
ext2fs_inode_table_loc(fs, i))
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 = ext2fs_inode_table_loc(rfs->old_fs, i);
new_blk = ext2fs_inode_table_loc(fs, i);
diff = new_blk - old_blk;
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
printf("Itable move group %d block %llu->%llu (diff %lld)\n",
i, old_blk, new_blk, diff);
#endif
if (!diff)
continue;
retval = io_channel_read_blk64(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-1, 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_blk64(fs->io, new_blk,
num, rfs->itable_buf);
if (retval) {
io_channel_write_blk64(fs->io, old_blk,
num, rfs->itable_buf);
goto errout;
}
if (n > diff) {
retval = io_channel_write_blk64(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;
}
for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
j < fs->inode_blocks_per_group ; j++, blk++)
ext2fs_block_alloc_stats2(fs, blk, -1);
ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
ext2fs_group_desc_csum_set(rfs->old_fs, i);
ext2fs_mark_super_dirty(rfs->old_fs);
ext2fs_flush(rfs->old_fs);
if (rfs->progress) {
retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
++moved, to_move);
if (retval)
goto errout;
}
}
mark_table_blocks(fs, fs->block_map);
ext2fs_flush(fs);
#ifdef RESIZE2FS_DEBUG
if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
printf("Inode table move finished.\n");
#endif
return 0;
errout:
return retval;
}
/*
* Fix the resize inode
*/
static errcode_t fix_resize_inode(ext2_filsys fs)
{
struct ext2_inode inode;
errcode_t retval;
char *block_buf = NULL;
if (!(fs->super->s_feature_compat &
EXT2_FEATURE_COMPAT_RESIZE_INODE))
return 0;
retval = ext2fs_get_mem(fs->blocksize, &block_buf);
if (retval) goto errout;
retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
if (retval) goto errout;
ext2fs_iblk_set(fs, &inode, 1);
retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
if (retval) goto errout;
if (!inode.i_block[EXT2_DIND_BLOCK]) {
/*
* Avoid zeroing out block #0; that's rude. This
* should never happen anyway since the filesystem
* should be fsck'ed and we assume it is consistent.
*/
fprintf(stderr, "%s",
_("Should never happen: resize inode corrupt!\n"));
exit(1);
}
memset(block_buf, 0, fs->blocksize);
retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1, block_buf);
if (retval) goto errout;
retval = ext2fs_create_resize_inode(fs);
if (retval)
goto errout;
errout:
if (block_buf)
ext2fs_free_mem(&block_buf);
return retval;
}
/*
* Finally, recalculate the summary information
*/
static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
{
blk64_t blk;
ext2_ino_t ino;
unsigned int group = 0;
unsigned int count = 0;
blk64_t total_blocks_free = 0;
int total_inodes_free = 0;
int group_free = 0;
int uninit = 0;
blk64_t super_blk, old_desc_blk, new_desc_blk;
int old_desc_blocks;
/*
* First calculate the block statistics
*/
uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
&new_desc_blk, 0);
if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
old_desc_blocks = fs->super->s_first_meta_bg;
else
old_desc_blocks = fs->desc_blocks +
fs->super->s_reserved_gdt_blocks;
for (blk = B2C(fs->super->s_first_data_block);
blk < ext2fs_blocks_count(fs->super);
blk += EXT2FS_CLUSTER_RATIO(fs)) {
if ((uninit &&
!(EQ_CLSTR(blk, super_blk) ||
((old_desc_blk && old_desc_blocks &&
GE_CLSTR(blk, old_desc_blk) &&
LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
+ fs->inode_blocks_per_group))))) ||
(!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
group_free++;
total_blocks_free++;
}
count++;
if ((count == fs->super->s_clusters_per_group) ||
EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
ext2fs_bg_free_blocks_count_set(fs, group, group_free);
ext2fs_group_desc_csum_set(fs, group);
group++;
if (group >= fs->group_desc_count)
break;
count = 0;
group_free = 0;
uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
&old_desc_blk,
&new_desc_blk, 0);
if (fs->super->s_feature_incompat &
EXT2_FEATURE_INCOMPAT_META_BG)
old_desc_blocks = fs->super->s_first_meta_bg;
else
old_desc_blocks = fs->desc_blocks +
fs->super->s_reserved_gdt_blocks;
}
}
total_blocks_free = C2B(total_blocks_free);
ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
/*
* Next, calculate the inode statistics
*/
group_free = 0;
count = 0;
group = 0;
/* Protect loop from wrap-around if s_inodes_count maxed */
uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
if (uninit ||
!ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
group_free++;
total_inodes_free++;
}
count++;
if ((count == fs->super->s_inodes_per_group) ||
(ino == fs->super->s_inodes_count)) {
ext2fs_bg_free_inodes_count_set(fs, group, group_free);
ext2fs_group_desc_csum_set(fs, group);
group++;
if (group >= fs->group_desc_count)
break;
count = 0;
group_free = 0;
uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
}
}
fs->super->s_free_inodes_count = total_inodes_free;
ext2fs_mark_super_dirty(fs);
return 0;
}
/*
* Journal may have been relocated; update the backup journal blocks
* in the superblock.
*/
static errcode_t fix_sb_journal_backup(ext2_filsys fs)
{
errcode_t retval;
struct ext2_inode inode;
if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
return 0;
/* External journal? Nothing to do. */
if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
return 0;
retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
if (retval)
return retval;
memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
fs->super->s_jnl_blocks[15] = inode.i_size_high;
fs->super->s_jnl_blocks[16] = inode.i_size;
fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
ext2fs_mark_super_dirty(fs);
return 0;
}
static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
int old_desc_blocks)
{
blk64_t super_blk, old_desc_blk, new_desc_blk;
int overhead;
/* inode table blocks plus allocation bitmaps */
overhead = fs->inode_blocks_per_group + 2;
ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
&old_desc_blk, &new_desc_blk, 0);
if ((grp == 0) || super_blk)
overhead++;
if (old_desc_blk)
overhead += old_desc_blocks;
else if (new_desc_blk)
overhead++;
return overhead;
}
/*
* calcluate the minimum number of blocks the given fs can be resized to
*/
blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
{
ext2_ino_t inode_count;
dgrp_t groups;
blk64_t blks_needed, data_blocks;
blk64_t grp, data_needed, last_start;
blk64_t overhead = 0;
int old_desc_blocks;
int extra_groups = 0;
int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
/*
* first figure out how many group descriptors we need to
* handle the number of inodes we have
*/
inode_count = fs->super->s_inodes_count -
fs->super->s_free_inodes_count;
blks_needed = ext2fs_div_ceil(inode_count,
fs->super->s_inodes_per_group) *
EXT2_BLOCKS_PER_GROUP(fs->super);
groups = ext2fs_div64_ceil(blks_needed,
EXT2_BLOCKS_PER_GROUP(fs->super));
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("fs has %d inodes, %d groups required.\n",
inode_count, groups);
#endif
/*
* number of old-style block group descriptor blocks
*/
if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
old_desc_blocks = fs->super->s_first_meta_bg;
else
old_desc_blocks = fs->desc_blocks +
fs->super->s_reserved_gdt_blocks;
/* calculate how many blocks are needed for data */
data_needed = ext2fs_blocks_count(fs->super) -
ext2fs_free_blocks_count(fs->super);
for (grp = 0; grp < fs->group_desc_count; grp++)
data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("fs requires %llu data blocks.\n", data_needed);
#endif
/*
* For ext4 we need to allow for up to a flex_bg worth of
* inode tables of slack space so the resize operation can be
* guaranteed to finish.
*/
if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
extra_groups = flexbg_size - (groups & (flexbg_size - 1));
data_needed += fs->inode_blocks_per_group * extra_groups;
extra_groups = groups % flexbg_size;
}
/*
* figure out how many data blocks we have given the number of groups
* we need for our inodes
*/
data_blocks = groups * EXT2_BLOCKS_PER_GROUP(fs->super);
last_start = 0;
for (grp = 0; grp < groups; grp++) {
overhead = calc_group_overhead(fs, grp, old_desc_blocks);
/*
* we want to keep track of how much data we can store in
* the groups leading up to the last group so we can determine
* how big the last group needs to be
*/
if (grp != (groups - 1))
last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
overhead;
data_blocks -= overhead;
}
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("With %d group(s), we have %llu blocks available.\n",
groups, data_blocks);
#endif
/*
* if we need more group descriptors in order to accomodate our data
* then we need to add them here
*/
while (data_needed > data_blocks) {
blk64_t remainder = data_needed - data_blocks;
dgrp_t extra_grps;
/* figure out how many more groups we need for the data */
extra_grps = ext2fs_div64_ceil(remainder,
EXT2_BLOCKS_PER_GROUP(fs->super));
data_blocks += extra_grps * EXT2_BLOCKS_PER_GROUP(fs->super);
/* ok we have to account for the last group */
overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
for (grp = groups; grp < groups+extra_grps; grp++) {
overhead = calc_group_overhead(fs, grp,
old_desc_blocks);
/*
* again, we need to see how much data we cram into
* all of the groups leading up to the last group
*/
if (grp != (groups + extra_grps - 1))
last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
- overhead;
data_blocks -= overhead;
}
groups += extra_grps;
extra_groups += extra_grps;
if (fs->super->s_feature_incompat
& EXT4_FEATURE_INCOMPAT_FLEX_BG
&& extra_groups > flexbg_size) {
/*
* For ext4 we need to allow for up to a flex_bg worth
* of inode tables of slack space so the resize
* operation can be guaranteed to finish.
*/
extra_groups = flexbg_size -
(groups & (flexbg_size - 1));
data_needed += (fs->inode_blocks_per_group *
extra_groups);
extra_groups = groups % flexbg_size;
}
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("Added %d extra group(s), "
"data_needed %llu, data_blocks %llu, "
"last_start %llu\n",
extra_grps, data_needed, data_blocks,
last_start);
#endif
}
/* now for the fun voodoo */
overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("Last group's overhead is %llu\n", overhead);
#endif
/*
* if this is the case then the last group is going to have data in it
* so we need to adjust the size of the last group accordingly
*/
if (last_start < data_needed) {
blk64_t remainder = data_needed - last_start;
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("Need %llu data blocks in last group\n",
remainder);
#endif
/*
* 50 is a magic number that mkfs/resize uses to see if its
* even worth making/resizing the fs. basically you need to
* have at least 50 blocks in addition to the blocks needed
* for the metadata in the last group
*/
if (remainder > 50)
overhead += remainder;
else
overhead += 50;
} else
overhead += 50;
overhead += fs->super->s_first_data_block;
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("Final size of last group is %lld\n", overhead);
#endif
/*
* since our last group doesn't have to be BLOCKS_PER_GROUP large, we
* only do groups-1, and then add the number of blocks needed to
* handle the group descriptor metadata+data that we need
*/
blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
blks_needed += overhead;
/*
* Make sure blks_needed covers the end of the inode table in
* the last block group.
*/
overhead = ext2fs_inode_table_loc(fs, groups-1) +
fs->inode_blocks_per_group;
if (blks_needed < overhead)
blks_needed = overhead;
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("Estimated blocks needed: %llu\n", blks_needed);
#endif
/*
* If at this point we've already added up more "needed" than
* the current size, just return current size as minimum.
*/
if (blks_needed >= ext2fs_blocks_count(fs->super))
return ext2fs_blocks_count(fs->super);
/*
* We need to reserve a few extra blocks if extents are
* enabled, in case we need to grow the extent tree. The more
* we shrink the file system, the more space we need.
*/
if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS) {
blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
blks_needed)/500;
#ifdef RESIZE2FS_DEBUG
if (flags & RESIZE_DEBUG_MIN_CALC)
printf("Extents safety margin: %llu\n", safe_margin);
#endif
blks_needed += safe_margin;
}
return blks_needed;
}