int shrink_fs(reiserfs_filsys_t reiserfs, unsigned long blocks)
{
unsigned long n_root_block;
unsigned int bmap_nr_new;
unsigned long int i;
fs = reiserfs;
rs = fs->s_rs;
/* warn about alpha version */
{
int c;
printf(
"You are running BETA version of reiserfs shrinker.\n"
"This version is only for testing or VERY CAREFUL use.\n"
"Backup of you data is recommended.\n\n"
"Do you want to continue? [y/N]:"
);
c = getchar();
if (c != 'y' && c != 'Y')
exit(1);
}
bmap_nr_new = (blocks - 1) / (8 * fs->s_blocksize) + 1;
/* is shrinking possible ? */
if (rs_block_count(rs) - blocks > rs_free_blocks(rs) + rs_bmap_nr(rs) - bmap_nr_new) {
fprintf(stderr, "resize_reiserfs: can\'t shrink fs; too many blocks already allocated\n");
return -1;
}
reiserfs_reopen(fs, O_RDWR);
set_state (fs->s_rs, REISERFS_ERROR_FS);
mark_buffer_uptodate(SB_BUFFER_WITH_SB(fs), 1);
mark_buffer_dirty(SB_BUFFER_WITH_SB(fs));
bwrite(SB_BUFFER_WITH_SB(fs));
/* calculate number of data blocks */
blocks_used =
SB_BLOCK_COUNT(fs)
- SB_FREE_BLOCKS(fs)
- SB_BMAP_NR(fs)
- SB_JOURNAL_SIZE(fs)
- REISERFS_DISK_OFFSET_IN_BYTES / fs->s_blocksize
- 2; /* superblock itself and 1 descriptor after the journal */
bmp = reiserfs_create_bitmap(rs_block_count(rs));
reiserfs_fetch_disk_bitmap(bmp, fs);
unused_block = 1;
if (opt_verbose) {
printf("Processing the tree: ");
fflush(stdout);
}
n_root_block = move_formatted_block(rs_root_block(rs), blocks, 0);
if (n_root_block) {
set_root_block (rs, n_root_block);
}
if (opt_verbose)
printf ("\n\nnodes processed (moved):\n"
"int %lu (%lu),\n"
"leaves %lu (%lu),\n"
"unfm %lu (%lu),\n"
"total %lu (%lu).\n\n",
int_node_cnt, int_moved_cnt,
leaf_node_cnt, leaf_moved_cnt,
unfm_node_cnt, unfm_moved_cnt,
(unsigned long)total_node_cnt, total_moved_cnt);
if (block_count_mismatch) {
fprintf(stderr, "resize_reiserfs: data block count %lu"
" doesn\'t match data block count %lu from super block\n",
(unsigned long)total_node_cnt, blocks_used);
}
#if 0
printf("check for used blocks in truncated region\n");
{
unsigned long l;
for (l = blocks; l < rs_block_count(rs); l++)
if (is_block_used(bmp, l))
printf("<%lu>", l);
printf("\n");
}
#endif /* 0 */
reiserfs_free_bitmap_blocks(fs);
set_free_blocks (rs, rs_free_blocks(rs) - (rs_block_count(rs) - blocks) + (rs_bmap_nr(rs) - bmap_nr_new));
set_block_count (rs, blocks);
set_bmap_nr (rs, bmap_nr_new);
reiserfs_read_bitmap_blocks(fs);
for (i = blocks; i < bmap_nr_new * fs->s_blocksize; i++)
reiserfs_bitmap_set_bit(bmp, i);
#if 0
PUT_SB_FREE_BLOCKS(s, SB_FREE_BLOCKS(s) - (SB_BLOCK_COUNT(s) - blocks) + (SB_BMAP_NR(s) - bmap_nr_new));
PUT_SB_BLOCK_COUNT(s, blocks);
PUT_SB_BMAP_NR(s, bmap_nr_new);
#endif
reiserfs_flush_bitmap(bmp, fs);
return 0;
}
int reiserfs_resize (struct super_block * s, unsigned long block_count_new)
{
struct reiserfs_super_block * sb;
struct reiserfs_bitmap_info *bitmap;
struct buffer_head * bh;
struct reiserfs_transaction_handle th;
unsigned int bmap_nr_new, bmap_nr;
unsigned int block_r_new, block_r;
struct reiserfs_list_bitmap * jb;
struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];
unsigned long int block_count, free_blocks;
int i;
int copy_size ;
sb = SB_DISK_SUPER_BLOCK(s);
if (SB_BLOCK_COUNT(s) >= block_count_new) {
printk("can\'t shrink filesystem on-line\n");
return -EINVAL;
}
/* check the device size */
bh = sb_bread(s, block_count_new - 1);
if (!bh) {
printk("reiserfs_resize: can\'t read last block\n");
return -EINVAL;
}
bforget(bh);
/* old disk layout detection; those partitions can be mounted, but
* cannot be resized */
if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
!= REISERFS_DISK_OFFSET_IN_BYTES ) {
printk("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
return -ENOTSUPP;
}
/* count used bits in last bitmap block */
block_r = SB_BLOCK_COUNT(s) -
(SB_BMAP_NR(s) - 1) * s->s_blocksize * 8;
/* count bitmap blocks in new fs */
bmap_nr_new = block_count_new / ( s->s_blocksize * 8 );
block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
if (block_r_new)
bmap_nr_new++;
else
block_r_new = s->s_blocksize * 8;
/* save old values */
block_count = SB_BLOCK_COUNT(s);
bmap_nr = SB_BMAP_NR(s);
/* resizing of reiserfs bitmaps (journal and real), if needed */
if (bmap_nr_new > bmap_nr) {
/* reallocate journal bitmaps */
if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
printk("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
unlock_super(s) ;
return -ENOMEM ;
}
/* the new journal bitmaps are zero filled, now we copy in the bitmap
** node pointers from the old journal bitmap structs, and then
** transfer the new data structures into the journal struct.
**
** using the copy_size var below allows this code to work for
** both shrinking and expanding the FS.
*/
copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr ;
copy_size = copy_size * sizeof(struct reiserfs_list_bitmap_node *) ;
for (i = 0 ; i < JOURNAL_NUM_BITMAPS ; i++) {
struct reiserfs_bitmap_node **node_tmp ;
jb = SB_JOURNAL(s)->j_list_bitmap + i ;
memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size) ;
/* just in case vfree schedules on us, copy the new
** pointer into the journal struct before freeing the
** old one
*/
node_tmp = jb->bitmaps ;
jb->bitmaps = jbitmap[i].bitmaps ;
vfree(node_tmp) ;
}
/* allocate additional bitmap blocks, reallocate array of bitmap
* block pointers */
bitmap = vmalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
if (!bitmap) {
printk("reiserfs_resize: unable to allocate memory.\n");
return -ENOMEM;
}
memset (bitmap, 0, sizeof (struct reiserfs_bitmap_info) * SB_BMAP_NR(s));
for (i = 0; i < bmap_nr; i++)
bitmap[i] = SB_AP_BITMAP(s)[i];
for (i = bmap_nr; i < bmap_nr_new; i++) {
bitmap[i].bh = sb_getblk(s, i * s->s_blocksize * 8);
memset(bitmap[i].bh->b_data, 0, sb_blocksize(sb));
reiserfs_test_and_set_le_bit(0, bitmap[i].bh->b_data);
set_buffer_uptodate(bitmap[i].bh);
mark_buffer_dirty(bitmap[i].bh) ;
sync_dirty_buffer(bitmap[i].bh);
// update bitmap_info stuff
bitmap[i].first_zero_hint=1;
bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
}
/* free old bitmap blocks array */
vfree(SB_AP_BITMAP(s));
SB_AP_BITMAP(s) = bitmap;
}
/* begin transaction */
journal_begin(&th, s, 10);
/* correct last bitmap blocks in old and new disk layout */
reiserfs_prepare_for_journal(s, SB_AP_BITMAP(s)[bmap_nr - 1].bh, 1);
for (i = block_r; i < s->s_blocksize * 8; i++)
reiserfs_test_and_clear_le_bit(i,
SB_AP_BITMAP(s)[bmap_nr - 1].bh->b_data);
SB_AP_BITMAP(s)[bmap_nr - 1].free_count += s->s_blocksize * 8 - block_r;
if ( !SB_AP_BITMAP(s)[bmap_nr - 1].first_zero_hint)
SB_AP_BITMAP(s)[bmap_nr - 1].first_zero_hint = block_r;
journal_mark_dirty(&th, s, SB_AP_BITMAP(s)[bmap_nr - 1].bh);
reiserfs_prepare_for_journal(s, SB_AP_BITMAP(s)[bmap_nr_new - 1].bh, 1);
for (i = block_r_new; i < s->s_blocksize * 8; i++)
reiserfs_test_and_set_le_bit(i,
SB_AP_BITMAP(s)[bmap_nr_new - 1].bh->b_data);
journal_mark_dirty(&th, s, SB_AP_BITMAP(s)[bmap_nr_new - 1].bh);
SB_AP_BITMAP(s)[bmap_nr_new - 1].free_count -= s->s_blocksize * 8 - block_r_new;
/* Extreme case where last bitmap is the only valid block in itself. */
if ( !SB_AP_BITMAP(s)[bmap_nr_new - 1].free_count )
SB_AP_BITMAP(s)[bmap_nr_new - 1].first_zero_hint = 0;
/* update super */
reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1) ;
free_blocks = SB_FREE_BLOCKS(s);
PUT_SB_FREE_BLOCKS(s, free_blocks + (block_count_new - block_count - (bmap_nr_new - bmap_nr)));
PUT_SB_BLOCK_COUNT(s, block_count_new);
PUT_SB_BMAP_NR(s, bmap_nr_new);
s->s_dirt = 1;
journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
SB_JOURNAL(s)->j_must_wait = 1;
journal_end(&th, s, 10);
return 0;
}
int reiserfs_resize(struct super_block *s, unsigned long block_count_new)
{
int err = 0;
struct reiserfs_super_block *sb;
struct reiserfs_bitmap_info *bitmap;
struct reiserfs_bitmap_info *info;
struct reiserfs_bitmap_info *old_bitmap = SB_AP_BITMAP(s);
struct buffer_head *bh;
struct reiserfs_transaction_handle th;
unsigned int bmap_nr_new, bmap_nr;
unsigned int block_r_new, block_r;
struct reiserfs_list_bitmap *jb;
struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];
unsigned long int block_count, free_blocks;
int i;
int copy_size;
sb = SB_DISK_SUPER_BLOCK(s);
if (SB_BLOCK_COUNT(s) >= block_count_new) {
printk("can\'t shrink filesystem on-line\n");
return -EINVAL;
}
/* check the device size */
bh = sb_bread(s, block_count_new - 1);
if (!bh) {
printk("reiserfs_resize: can\'t read last block\n");
return -EINVAL;
}
bforget(bh);
/* old disk layout detection; those partitions can be mounted, but
* cannot be resized */
if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
!= REISERFS_DISK_OFFSET_IN_BYTES) {
printk
("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
return -ENOTSUPP;
}
/* count used bits in last bitmap block */
block_r = SB_BLOCK_COUNT(s) -
(reiserfs_bmap_count(s) - 1) * s->s_blocksize * 8;
/* count bitmap blocks in new fs */
bmap_nr_new = block_count_new / (s->s_blocksize * 8);
block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
if (block_r_new)
bmap_nr_new++;
else
block_r_new = s->s_blocksize * 8;
/* save old values */
block_count = SB_BLOCK_COUNT(s);
bmap_nr = reiserfs_bmap_count(s);
/* resizing of reiserfs bitmaps (journal and real), if needed */
if (bmap_nr_new > bmap_nr) {
/* reallocate journal bitmaps */
if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
printk
("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
return -ENOMEM;
}
/* the new journal bitmaps are zero filled, now we copy in the bitmap
** node pointers from the old journal bitmap structs, and then
** transfer the new data structures into the journal struct.
**
** using the copy_size var below allows this code to work for
** both shrinking and expanding the FS.
*/
copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr;
copy_size =
copy_size * sizeof(struct reiserfs_list_bitmap_node *);
for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
struct reiserfs_bitmap_node **node_tmp;
jb = SB_JOURNAL(s)->j_list_bitmap + i;
memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size);
/* just in case vfree schedules on us, copy the new
** pointer into the journal struct before freeing the
** old one
*/
node_tmp = jb->bitmaps;
jb->bitmaps = jbitmap[i].bitmaps;
vfree(node_tmp);
}
/* allocate additional bitmap blocks, reallocate array of bitmap
* block pointers */
bitmap =
vzalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
if (!bitmap) {
/* Journal bitmaps are still supersized, but the memory isn't
* leaked, so I guess it's ok */
printk("reiserfs_resize: unable to allocate memory.\n");
return -ENOMEM;
}
for (i = 0; i < bmap_nr; i++)
bitmap[i] = old_bitmap[i];
/* This doesn't go through the journal, but it doesn't have to.
* The changes are still atomic: We're synced up when the journal
* transaction begins, and the new bitmaps don't matter if the
* transaction fails. */
for (i = bmap_nr; i < bmap_nr_new; i++) {
/* don't use read_bitmap_block since it will cache
* the uninitialized bitmap */
bh = sb_bread(s, i * s->s_blocksize * 8);
if (!bh) {
vfree(bitmap);
return -EIO;
}
memset(bh->b_data, 0, sb_blocksize(sb));
reiserfs_set_le_bit(0, bh->b_data);
reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);
set_buffer_uptodate(bh);
mark_buffer_dirty(bh);
reiserfs_write_unlock(s);
sync_dirty_buffer(bh);
reiserfs_write_lock(s);
// update bitmap_info stuff
bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
brelse(bh);
}
/* free old bitmap blocks array */
SB_AP_BITMAP(s) = bitmap;
vfree(old_bitmap);
}
/* begin transaction, if there was an error, it's fine. Yes, we have
* incorrect bitmaps now, but none of it is ever going to touch the
* disk anyway. */
err = journal_begin(&th, s, 10);
if (err)
return err;
/* Extend old last bitmap block - new blocks have been made available */
info = SB_AP_BITMAP(s) + bmap_nr - 1;
bh = reiserfs_read_bitmap_block(s, bmap_nr - 1);
if (!bh) {
int jerr = journal_end(&th, s, 10);
if (jerr)
return jerr;
return -EIO;
}
reiserfs_prepare_for_journal(s, bh, 1);
for (i = block_r; i < s->s_blocksize * 8; i++)
reiserfs_clear_le_bit(i, bh->b_data);
info->free_count += s->s_blocksize * 8 - block_r;
journal_mark_dirty(&th, s, bh);
brelse(bh);
/* Correct new last bitmap block - It may not be full */
info = SB_AP_BITMAP(s) + bmap_nr_new - 1;
bh = reiserfs_read_bitmap_block(s, bmap_nr_new - 1);
if (!bh) {
int jerr = journal_end(&th, s, 10);
if (jerr)
return jerr;
return -EIO;
}
reiserfs_prepare_for_journal(s, bh, 1);
for (i = block_r_new; i < s->s_blocksize * 8; i++)
reiserfs_set_le_bit(i, bh->b_data);
journal_mark_dirty(&th, s, bh);
brelse(bh);
info->free_count -= s->s_blocksize * 8 - block_r_new;
/* update super */
reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
free_blocks = SB_FREE_BLOCKS(s);
PUT_SB_FREE_BLOCKS(s,
free_blocks + (block_count_new - block_count -
(bmap_nr_new - bmap_nr)));
PUT_SB_BLOCK_COUNT(s, block_count_new);
PUT_SB_BMAP_NR(s, bmap_would_wrap(bmap_nr_new) ? : bmap_nr_new);
journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
SB_JOURNAL(s)->j_must_wait = 1;
return journal_end(&th, s, 10);
}
