2 * linux/fs/ext3/resize.c
4 * Support for resizing an ext3 filesystem while it is mounted.
6 * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com>
8 * This could probably be made into a module, because it is not often in use.
11 #include <linux/config.h>
15 #include <linux/sched.h>
16 #include <linux/smp_lock.h>
17 #include <linux/ext3_jbd.h>
19 #include <linux/errno.h>
20 #include <linux/slab.h>
23 #define outside(b, first, last) ((b) < (first) || (b) >= (last))
24 #define inside(b, first, last) ((b) >= (first) && (b) < (last))
26 static int verify_group_input(struct super_block *sb,
27 struct ext3_new_group_data *input)
29 struct ext3_sb_info *sbi = EXT3_SB(sb);
30 struct ext3_super_block *es = sbi->s_es;
31 unsigned start = le32_to_cpu(es->s_blocks_count);
32 unsigned end = start + input->blocks_count;
33 unsigned group = input->group;
34 unsigned itend = input->inode_table + EXT3_SB(sb)->s_itb_per_group;
35 unsigned overhead = ext3_bg_has_super(sb, group) ?
36 (1 + ext3_bg_num_gdb(sb, group) +
37 le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
38 unsigned metaend = start + overhead;
39 struct buffer_head *bh;
40 int free_blocks_count;
43 input->free_blocks_count = free_blocks_count =
44 input->blocks_count - 2 - overhead - sbi->s_itb_per_group;
46 if (test_opt(sb, DEBUG))
47 printk("EXT3-fs: adding %s group %u: %u blocks "
48 "(%d free, %u reserved)\n",
49 ext3_bg_has_super(sb, input->group) ? "normal" :
50 "no-super", input->group, input->blocks_count,
51 free_blocks_count, input->reserved_blocks);
53 if (group != sbi->s_groups_count)
54 ext3_warning(sb, __FUNCTION__,
55 "Cannot add at group %u (only %lu groups)",
56 input->group, sbi->s_groups_count);
57 else if ((start - le32_to_cpu(es->s_first_data_block)) %
58 EXT3_BLOCKS_PER_GROUP(sb))
59 ext3_warning(sb, __FUNCTION__, "Last group not full");
60 else if (input->reserved_blocks > input->blocks_count / 5)
61 ext3_warning(sb, __FUNCTION__, "Reserved blocks too high (%u)",
62 input->reserved_blocks);
63 else if (free_blocks_count < 0)
64 ext3_warning(sb, __FUNCTION__, "Bad blocks count %u",
66 else if (!(bh = sb_bread(sb, end - 1)))
67 ext3_warning(sb, __FUNCTION__, "Cannot read last block (%u)",
69 else if (outside(input->block_bitmap, start, end))
70 ext3_warning(sb, __FUNCTION__,
71 "Block bitmap not in group (block %u)",
73 else if (outside(input->inode_bitmap, start, end))
74 ext3_warning(sb, __FUNCTION__,
75 "Inode bitmap not in group (block %u)",
77 else if (outside(input->inode_table, start, end) ||
78 outside(itend - 1, start, end))
79 ext3_warning(sb, __FUNCTION__,
80 "Inode table not in group (blocks %u-%u)",
81 input->inode_table, itend - 1);
82 else if (input->inode_bitmap == input->block_bitmap)
83 ext3_warning(sb, __FUNCTION__,
84 "Block bitmap same as inode bitmap (%u)",
86 else if (inside(input->block_bitmap, input->inode_table, itend))
87 ext3_warning(sb, __FUNCTION__,
88 "Block bitmap (%u) in inode table (%u-%u)",
89 input->block_bitmap, input->inode_table, itend-1);
90 else if (inside(input->inode_bitmap, input->inode_table, itend))
91 ext3_warning(sb, __FUNCTION__,
92 "Inode bitmap (%u) in inode table (%u-%u)",
93 input->inode_bitmap, input->inode_table, itend-1);
94 else if (inside(input->block_bitmap, start, metaend))
95 ext3_warning(sb, __FUNCTION__,
96 "Block bitmap (%u) in GDT table (%u-%u)",
97 input->block_bitmap, start, metaend - 1);
98 else if (inside(input->inode_bitmap, start, metaend))
99 ext3_warning(sb, __FUNCTION__,
100 "Inode bitmap (%u) in GDT table (%u-%u)",
101 input->inode_bitmap, start, metaend - 1);
102 else if (inside(input->inode_table, start, metaend) ||
103 inside(itend - 1, start, metaend))
104 ext3_warning(sb, __FUNCTION__,
105 "Inode table (%u-%u) overlaps GDT table (%u-%u)",
106 input->inode_table, itend - 1, start, metaend - 1);
115 static struct buffer_head *bclean(handle_t *handle, struct super_block *sb,
118 struct buffer_head *bh;
121 bh = sb_getblk(sb, blk);
122 set_buffer_uptodate(bh);
123 if ((err = ext3_journal_get_write_access(handle, bh))) {
127 memset(bh->b_data, 0, sb->s_blocksize);
133 * To avoid calling the atomic setbit hundreds or thousands of times, we only
134 * need to use it within a single byte (to ensure we get endianness right).
135 * We can use memset for the rest of the bitmap as there are no other users.
137 static void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
141 if (start_bit >= end_bit)
144 ext3_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
145 for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
146 ext3_set_bit(i, bitmap);
148 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
152 * Set up the block and inode bitmaps, and the inode table for the new group.
153 * This doesn't need to be part of the main transaction, since we are only
154 * changing blocks outside the actual filesystem. We still do journaling to
155 * ensure the recovery is correct in case of a failure just after resize.
156 * If any part of this fails, we simply abort the resize.
158 * We only pass inode because of the ext3 journal wrappers.
160 static int setup_new_group_blocks(struct super_block *sb, struct inode *inode,
161 struct ext3_new_group_data *input)
163 struct ext3_sb_info *sbi = EXT3_SB(sb);
164 unsigned long start = input->group * sbi->s_blocks_per_group +
165 le32_to_cpu(sbi->s_es->s_first_data_block);
166 int reserved_gdb = ext3_bg_has_super(sb, input->group) ?
167 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0;
168 unsigned long gdblocks = ext3_bg_num_gdb(sb, input->group);
169 struct buffer_head *bh;
176 handle = ext3_journal_start(inode, reserved_gdb + gdblocks +
177 2 + sbi->s_itb_per_group);
179 return PTR_ERR(handle);
182 if (input->group != sbi->s_groups_count) {
187 if (IS_ERR(bh = bclean(handle, sb, input->block_bitmap))) {
192 if (ext3_bg_has_super(sb, input->group)) {
193 ext3_debug("mark backup superblock %#04lx (+0)\n", start);
194 ext3_set_bit(0, bh->b_data);
197 /* Copy all of the GDT blocks into the backup in this group */
198 for (i = 0, bit = 1, block = start + 1;
199 i < gdblocks; i++, block++, bit++) {
200 struct buffer_head *gdb;
202 ext3_debug("update backup group %#04lx (+%d)\n", block, bit);
204 gdb = sb_getblk(sb, block);
205 set_buffer_uptodate(gdb);
206 if ((err = ext3_journal_get_write_access(handle, gdb))) {
210 memcpy(gdb->b_data, sbi->s_group_desc[i], bh->b_size);
211 ext3_journal_dirty_metadata(handle, gdb);
212 ext3_set_bit(bit, bh->b_data);
216 /* Zero out all of the reserved backup group descriptor table blocks */
217 for (i = 0, bit = gdblocks + 1, block = start + bit;
218 i < reserved_gdb; i++, block++, bit++) {
219 struct buffer_head *gdb;
221 ext3_debug("clear reserved block %#04lx (+%d)\n", block, bit);
223 if (IS_ERR(gdb = bclean(handle, sb, block))) {
227 ext3_journal_dirty_metadata(handle, gdb);
228 ext3_set_bit(bit, bh->b_data);
231 ext3_debug("mark block bitmap %#04x (+%ld)\n", input->block_bitmap,
232 input->block_bitmap - start);
233 ext3_set_bit(input->block_bitmap - start, bh->b_data);
234 ext3_debug("mark inode bitmap %#04x (+%ld)\n", input->inode_bitmap,
235 input->inode_bitmap - start);
236 ext3_set_bit(input->inode_bitmap - start, bh->b_data);
238 /* Zero out all of the inode table blocks */
239 for (i = 0, block = input->inode_table, bit = block - start;
240 i < sbi->s_itb_per_group; i++, bit++, block++) {
241 struct buffer_head *it;
243 ext3_debug("clear inode block %#04x (+%ld)\n", block, bit);
244 if (IS_ERR(it = bclean(handle, sb, block))) {
248 ext3_journal_dirty_metadata(handle, it);
250 ext3_set_bit(bit, bh->b_data);
252 mark_bitmap_end(input->blocks_count, EXT3_BLOCKS_PER_GROUP(sb),
254 ext3_journal_dirty_metadata(handle, bh);
257 /* Mark unused entries in inode bitmap used */
258 ext3_debug("clear inode bitmap %#04x (+%ld)\n",
259 input->inode_bitmap, input->inode_bitmap - start);
260 if (IS_ERR(bh = bclean(handle, sb, input->inode_bitmap))) {
265 mark_bitmap_end(EXT3_INODES_PER_GROUP(sb), EXT3_BLOCKS_PER_GROUP(sb),
267 ext3_journal_dirty_metadata(handle, bh);
273 if ((err2 = ext3_journal_stop(handle)) && !err)
280 * Iterate through the groups which hold BACKUP superblock/GDT copies in an
281 * ext3 filesystem. The counters should be initialized to 1, 5, and 7 before
282 * calling this for the first time. In a sparse filesystem it will be the
283 * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
284 * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
286 unsigned ext3_list_backups(struct super_block *sb, unsigned *three,
287 unsigned *five, unsigned *seven)
289 unsigned *min = three;
293 if (!EXT3_HAS_RO_COMPAT_FEATURE(sb,
294 EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
316 * Check that all of the backup GDT blocks are held in the primary GDT block.
317 * It is assumed that they are stored in group order. Returns the number of
318 * groups in current filesystem that have BACKUPS, or -ve error code.
320 static int verify_reserved_gdb(struct super_block *sb,
321 struct buffer_head *primary)
323 const unsigned long blk = primary->b_blocknr;
324 const unsigned long end = EXT3_SB(sb)->s_groups_count;
329 __u32 *p = (__u32 *)primary->b_data;
332 while ((grp = ext3_list_backups(sb, &three, &five, &seven)) < end) {
333 if (le32_to_cpu(*p++) != grp * EXT3_BLOCKS_PER_GROUP(sb) + blk){
334 ext3_warning(sb, __FUNCTION__,
335 "reserved GDT %ld missing grp %d (%ld)\n",
337 grp * EXT3_BLOCKS_PER_GROUP(sb) + blk);
340 if (++gdbackups > EXT3_ADDR_PER_BLOCK(sb))
348 * Called when we need to bring a reserved group descriptor table block into
349 * use from the resize inode. The primary copy of the new GDT block currently
350 * is an indirect block (under the double indirect block in the resize inode).
351 * The new backup GDT blocks will be stored as leaf blocks in this indirect
352 * block, in group order. Even though we know all the block numbers we need,
353 * we check to ensure that the resize inode has actually reserved these blocks.
355 * Don't need to update the block bitmaps because the blocks are still in use.
357 * We get all of the error cases out of the way, so that we are sure to not
358 * fail once we start modifying the data on disk, because JBD has no rollback.
360 static int add_new_gdb(handle_t *handle, struct inode *inode,
361 struct ext3_new_group_data *input,
362 struct buffer_head **primary)
364 struct super_block *sb = inode->i_sb;
365 struct ext3_super_block *es = EXT3_SB(sb)->s_es;
366 unsigned long gdb_num = input->group / EXT3_DESC_PER_BLOCK(sb);
367 unsigned long gdb_off = input->group % EXT3_DESC_PER_BLOCK(sb);
368 unsigned long gdblock = EXT3_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num;
369 struct buffer_head **o_group_desc, **n_group_desc;
370 struct buffer_head *dind;
372 struct ext3_iloc iloc;
376 if (test_opt(sb, DEBUG))
377 printk("EXT3-fs: ext3_add_new_gdb: adding group block %lu\n",
381 * If we are not using the primary superblock/GDT copy don't resize,
382 * because the user tools have no way of handling this. Probably a
383 * bad time to do it anyways.
385 if (EXT3_SB(sb)->s_sbh->b_blocknr !=
386 le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block)) {
387 ext3_warning(sb, __FUNCTION__,
388 "won't resize using backup superblock at %lu\n",
389 EXT3_SB(sb)->s_sbh->b_blocknr);
393 *primary = sb_bread(sb, gdblock);
397 if ((gdbackups = verify_reserved_gdb(sb, *primary)) < 0) {
402 data = EXT3_I(inode)->i_data + EXT3_DIND_BLOCK;
403 dind = sb_bread(sb, le32_to_cpu(*data));
409 data = (__u32 *)dind->b_data;
410 if (le32_to_cpu(data[gdb_num % EXT3_ADDR_PER_BLOCK(sb)]) != gdblock) {
411 ext3_warning(sb, __FUNCTION__,
412 "new group %u GDT block %lu not reserved\n",
413 input->group, gdblock);
418 if ((err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh)))
421 if ((err = ext3_journal_get_write_access(handle, *primary)))
424 if ((err = ext3_journal_get_write_access(handle, dind)))
427 /* ext3_reserve_inode_write() gets a reference on the iloc */
428 if ((err = ext3_reserve_inode_write(handle, inode, &iloc)))
431 n_group_desc = (struct buffer_head **)kmalloc((gdb_num + 1) *
432 sizeof(struct buffer_head *), GFP_KERNEL);
435 ext3_warning (sb, __FUNCTION__,
436 "not enough memory for %lu groups", gdb_num + 1);
441 * Finally, we have all of the possible failures behind us...
443 * Remove new GDT block from inode double-indirect block and clear out
444 * the new GDT block for use (which also "frees" the backup GDT blocks
445 * from the reserved inode). We don't need to change the bitmaps for
446 * these blocks, because they are marked as in-use from being in the
447 * reserved inode, and will become GDT blocks (primary and backup).
450 printk("removing block %d = %ld from dindir %ld[%ld]\n",
451 ((__u32 *)(dind->b_data))[gdb_off], gdblock, dind->b_blocknr,
453 data[gdb_num % EXT3_ADDR_PER_BLOCK(sb)] = 0;
454 ext3_journal_dirty_metadata(handle, dind);
456 inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9;
457 ext3_mark_iloc_dirty(handle, inode, &iloc);
458 memset((*primary)->b_data, 0, sb->s_blocksize);
459 ext3_journal_dirty_metadata(handle, *primary);
461 o_group_desc = EXT3_SB(sb)->s_group_desc;
462 memcpy(n_group_desc, o_group_desc,
463 EXT3_SB(sb)->s_gdb_count * sizeof(struct buffer_head *));
464 n_group_desc[gdb_num] = *primary;
465 EXT3_SB(sb)->s_group_desc = n_group_desc;
466 EXT3_SB(sb)->s_gdb_count++;
469 es->s_reserved_gdt_blocks =
470 cpu_to_le16(le16_to_cpu(es->s_reserved_gdt_blocks) - 1);
471 ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
476 //ext3_journal_release_buffer(handle, iloc.bh);
479 //ext3_journal_release_buffer(handle, dind);
481 //ext3_journal_release_buffer(handle, *primary);
483 //ext3_journal_release_buffer(handle, *primary);
489 ext3_debug("leaving with error %d\n", err);
494 * Called when we are adding a new group which has a backup copy of each of
495 * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks.
496 * We need to add these reserved backup GDT blocks to the resize inode, so
497 * that they are kept for future resizing and not allocated to files.
499 * Each reserved backup GDT block will go into a different indirect block.
500 * The indirect blocks are actually the primary reserved GDT blocks,
501 * so we know in advance what their block numbers are. We only get the
502 * double-indirect block to verify it is pointing to the primary reserved
503 * GDT blocks so we don't overwrite a data block by accident. The reserved
504 * backup GDT blocks are stored in their reserved primary GDT block.
506 static int reserve_backup_gdb(handle_t *handle, struct inode *inode,
507 struct ext3_new_group_data *input)
509 struct super_block *sb = inode->i_sb;
510 int reserved_gdb =le16_to_cpu(EXT3_SB(sb)->s_es->s_reserved_gdt_blocks);
511 struct buffer_head **primary;
512 struct buffer_head *dind;
513 struct ext3_iloc iloc;
520 primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_KERNEL);
524 data = EXT3_I(inode)->i_data + EXT3_DIND_BLOCK;
525 dind = sb_bread(sb, le32_to_cpu(*data));
531 blk = EXT3_SB(sb)->s_sbh->b_blocknr + 1 + EXT3_SB(sb)->s_gdb_count;
532 data = (__u32 *)dind->b_data + EXT3_SB(sb)->s_gdb_count;
533 end = (__u32 *)dind->b_data + EXT3_ADDR_PER_BLOCK(sb);
535 /* Get each reserved primary GDT block and verify it holds backups */
536 for (res = 0; res < reserved_gdb; res++, blk++) {
537 if (le32_to_cpu(*data) != blk) {
538 ext3_warning(sb, __FUNCTION__,
539 "reserved block %lu not at offset %ld\n",
540 blk, (long)(data - (__u32 *)dind->b_data));
544 primary[res] = sb_bread(sb, blk);
549 if ((gdbackups = verify_reserved_gdb(sb, primary[res])) < 0) {
550 brelse(primary[res]);
555 data = (__u32 *)dind->b_data;
558 for (i = 0; i < reserved_gdb; i++) {
559 if ((err = ext3_journal_get_write_access(handle, primary[i]))) {
562 for (j = 0; j < i; j++)
563 ext3_journal_release_buffer(handle, primary[j]);
569 if ((err = ext3_reserve_inode_write(handle, inode, &iloc)))
573 * Finally we can add each of the reserved backup GDT blocks from
574 * the new group to its reserved primary GDT block.
576 blk = input->group * EXT3_BLOCKS_PER_GROUP(sb);
577 for (i = 0; i < reserved_gdb; i++) {
579 data = (__u32 *)primary[i]->b_data;
580 /* printk("reserving backup %lu[%u] = %lu\n",
581 primary[i]->b_blocknr, gdbackups,
582 blk + primary[i]->b_blocknr); */
583 data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr);
584 err2 = ext3_journal_dirty_metadata(handle, primary[i]);
588 inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9;
589 ext3_mark_iloc_dirty(handle, inode, &iloc);
593 brelse(primary[res]);
603 * Update the backup copies of the ext3 metadata. These don't need to be part
604 * of the main resize transaction, because e2fsck will re-write them if there
605 * is a problem (basically only OOM will cause a problem). However, we
606 * _should_ update the backups if possible, in case the primary gets trashed
607 * for some reason and we need to run e2fsck from a backup superblock. The
608 * important part is that the new block and inode counts are in the backup
609 * superblocks, and the location of the new group metadata in the GDT backups.
611 * We do not need lock_super() for this, because these blocks are not
612 * otherwise touched by the filesystem code when it is mounted. We don't
613 * need to worry about last changing from sbi->s_groups_count, because the
614 * worst that can happen is that we do not copy the full number of backups
615 * at this time. The resize which changed s_groups_count will backup again.
617 * We only pass inode because of the ext3 journal wrappers.
619 static void update_backups(struct super_block *sb, struct inode *inode,
620 int blk_off, char *data, int size)
622 struct ext3_sb_info *sbi = EXT3_SB(sb);
623 const unsigned long last = sbi->s_groups_count;
624 const int bpg = EXT3_BLOCKS_PER_GROUP(sb);
629 int rest = sb->s_blocksize - size;
633 handle = ext3_journal_start(inode, EXT3_MAX_TRANS_DATA);
634 if (IS_ERR(handle)) {
636 err = PTR_ERR(handle);
640 while ((group = ext3_list_backups(sb, &three, &five, &seven)) < last) {
641 struct buffer_head *bh;
643 /* Out of journal space, and can't get more - abort - so sad */
644 if (handle->h_buffer_credits == 0 &&
645 ext3_journal_extend(handle, EXT3_MAX_TRANS_DATA) &&
646 (err = ext3_journal_restart(handle, EXT3_MAX_TRANS_DATA)))
649 bh = sb_getblk(sb, group * bpg + blk_off);
650 set_buffer_uptodate(bh);
651 ext3_debug(sb, __FUNCTION__, "update metadata backup %#04lx\n",
653 if ((err = ext3_journal_get_write_access(handle, bh)))
655 memcpy(bh->b_data, data, size);
657 memset(bh->b_data + size, 0, rest);
658 ext3_journal_dirty_metadata(handle, bh);
661 if ((err2 = ext3_journal_stop(handle)) && !err)
665 * Ugh! Need to have e2fsck write the backup copies. It is too
666 * late to revert the resize, we shouldn't fail just because of
667 * the backup copies (they are only needed in case of corruption).
669 * However, if we got here we have a journal problem too, so we
670 * can't really start a transaction to mark the superblock.
671 * Chicken out and just set the flag on the hope it will be written
672 * to disk, and if not - we will simply wait until next fsck.
676 ext3_warning(sb, __FUNCTION__,
677 "can't update backup for group %d (err %d), "
678 "forcing fsck on next reboot\n", group, err);
679 sbi->s_mount_state &= ~EXT3_VALID_FS;
680 sbi->s_es->s_state &= ~cpu_to_le16(EXT3_VALID_FS);
681 mark_buffer_dirty(sbi->s_sbh);
685 /* Add group descriptor data to an existing or new group descriptor block.
686 * Ensure we handle all possible error conditions _before_ we start modifying
687 * the filesystem, because we cannot abort the transaction and not have it
688 * write the data to disk.
690 * If we are on a GDT block boundary, we need to get the reserved GDT block.
691 * Otherwise, we may need to add backup GDT blocks for a sparse group.
693 * We only need to hold the superblock lock while we are actually adding
694 * in the new group's counts to the superblock. Prior to that we have
695 * not really "added" the group at all. We re-check that we are still
696 * adding in the last group in case things have changed since verifying.
698 int ext3_group_add(struct super_block *sb, struct ext3_new_group_data *input)
700 struct ext3_sb_info *sbi = EXT3_SB(sb);
701 struct ext3_super_block *es = sbi->s_es;
702 int reserved_gdb = ext3_bg_has_super(sb, input->group) ?
703 le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
704 struct buffer_head *primary = NULL;
705 struct ext3_group_desc *gdp;
706 struct inode *inode = NULL;
709 int gdb_off, gdb_num;
712 gdb_num = input->group / EXT3_DESC_PER_BLOCK(sb);
713 gdb_off = input->group % EXT3_DESC_PER_BLOCK(sb);
715 if (gdb_off == 0 && !EXT3_HAS_RO_COMPAT_FEATURE(sb,
716 EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
717 ext3_warning(sb, __FUNCTION__,
718 "Can't resize non-sparse filesystem further\n");
722 if (reserved_gdb || gdb_off == 0) {
723 if (!EXT3_HAS_COMPAT_FEATURE(sb,
724 EXT3_FEATURE_COMPAT_RESIZE_INODE)){
725 ext3_warning(sb, __FUNCTION__,
726 "No reserved GDT blocks, can't resize\n");
729 inode = iget(sb, EXT3_RESIZE_INO);
730 if (!inode || is_bad_inode(inode)) {
731 ext3_warning(sb, __FUNCTION__,
732 "Error opening resize inode\n");
737 /* Used only for ext3 journal wrapper functions to get sb */
742 if ((err = verify_group_input(sb, input)))
745 if ((err = setup_new_group_blocks(sb, inode, input)))
749 * We will always be modifying at least the superblock and a GDT
750 * block. If we are adding a group past the last current GDT block,
751 * we will also modify the inode and the dindirect block. If we
752 * are adding a group with superblock/GDT backups we will also
753 * modify each of the reserved GDT dindirect blocks.
755 handle = ext3_journal_start(inode, ext3_bg_has_super(sb, input->group) ?
756 3 + reserved_gdb : 4);
757 if (IS_ERR(handle)) {
758 err = PTR_ERR(handle);
763 if (input->group != EXT3_SB(sb)->s_groups_count) {
764 ext3_warning(sb, __FUNCTION__,
765 "multiple resizers run on filesystem!\n");
769 if ((err = ext3_journal_get_write_access(handle, sbi->s_sbh)))
773 * We will only either add reserved group blocks to a backup group
774 * or remove reserved blocks for the first group in a new group block.
775 * Doing both would be mean more complex code, and sane people don't
776 * use non-sparse filesystems anymore. This is already checked above.
779 primary = sbi->s_group_desc[gdb_num];
780 if ((err = ext3_journal_get_write_access(handle, primary)))
783 if (reserved_gdb && ext3_bg_num_gdb(sb, input->group) &&
784 (err = reserve_backup_gdb(handle, inode, input)))
786 } else if ((err = add_new_gdb(handle, inode, input, &primary)))
789 /* Finally update group descriptor block for new group */
790 gdp = (struct ext3_group_desc *)primary->b_data + gdb_off;
792 gdp->bg_block_bitmap = cpu_to_le32(input->block_bitmap);
793 gdp->bg_inode_bitmap = cpu_to_le32(input->inode_bitmap);
794 gdp->bg_inode_table = cpu_to_le32(input->inode_table);
795 gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count);
796 gdp->bg_free_inodes_count = cpu_to_le16(EXT3_INODES_PER_GROUP(sb));
798 EXT3_SB(sb)->s_groups_count++;
799 ext3_journal_dirty_metadata(handle, primary);
801 /* Update superblock with new block counts */
802 es->s_blocks_count = cpu_to_le32(le32_to_cpu(es->s_blocks_count) +
803 input->blocks_count);
804 es->s_free_blocks_count =
805 cpu_to_le32(le32_to_cpu(es->s_free_blocks_count) +
806 input->free_blocks_count);
807 es->s_r_blocks_count = cpu_to_le32(le32_to_cpu(es->s_r_blocks_count) +
808 input->reserved_blocks);
809 es->s_inodes_count = cpu_to_le32(le32_to_cpu(es->s_inodes_count) +
810 EXT3_INODES_PER_GROUP(sb));
811 es->s_free_inodes_count =
812 cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) +
813 EXT3_INODES_PER_GROUP(sb));
814 ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
820 if ((err2 = ext3_journal_stop(handle)) && !err)
823 update_backups(sb, inode, sbi->s_sbh->b_blocknr, (char *)es,
824 sizeof(struct ext3_super_block));
825 update_backups(sb, inode, primary->b_blocknr, primary->b_data,
832 } /* ext3_group_add */
834 /* Extend the filesystem to the new number of blocks specified. This entry
835 * point is only used to extend the current filesystem to the end of the last
836 * existing group. It can be accessed via ioctl, or by "remount,resize=<size>"
837 * for emergencies (because it has no dependencies on reserved blocks).
839 * If we _really_ wanted, we could use default values to call ext3_group_add()
840 * allow the "remount" trick to work for arbitrary resizing, assuming enough
841 * GDT blocks are reserved to grow to the desired size.
843 int ext3_group_extend(struct super_block *sb, struct ext3_super_block *es,
844 unsigned long n_blocks_count)
846 unsigned long o_blocks_count;
847 unsigned long o_groups_count;
851 struct buffer_head * bh;
855 o_blocks_count = le32_to_cpu(es->s_blocks_count);
856 o_groups_count = EXT3_SB(sb)->s_groups_count;
858 if (test_opt(sb, DEBUG))
859 printk("EXT3-fs: extending last group from %lu to %lu blocks\n",
860 o_blocks_count, n_blocks_count);
862 if (n_blocks_count == 0 || n_blocks_count == o_blocks_count)
865 if (n_blocks_count < o_blocks_count) {
866 ext3_warning(sb, __FUNCTION__,
867 "can't shrink FS - resize aborted");
871 /* Handle the remaining blocks in the last group only. */
872 last = (o_blocks_count - le32_to_cpu(es->s_first_data_block)) %
873 EXT3_BLOCKS_PER_GROUP(sb);
876 ext3_warning(sb, __FUNCTION__,
877 "need to use ext2online to resize further\n");
881 add = EXT3_BLOCKS_PER_GROUP(sb) - last;
883 if (o_blocks_count + add > n_blocks_count)
884 add = n_blocks_count - o_blocks_count;
886 if (o_blocks_count + add < n_blocks_count)
887 ext3_warning(sb, __FUNCTION__,
888 "will only finish group (%lu blocks, %u new)",
889 o_blocks_count + add, add);
891 /* See if the device is actually as big as what was requested */
892 bh = sb_bread(sb, o_blocks_count + add -1);
894 ext3_warning(sb, __FUNCTION__,
895 "can't read last block, resize aborted");
900 /* Get a bogus inode to "free" the new blocks in this group. */
901 if (!(inode = new_inode(sb))) {
902 ext3_warning(sb, __FUNCTION__,
903 "error getting dummy resize inode");
908 EXT3_I(inode)->i_state = EXT3_STATE_RESIZE;
910 /* We will update the superblock, one block bitmap, and
911 * one group descriptor via ext3_free_blocks().
913 handle = ext3_journal_start(inode, 3);
914 if (IS_ERR(handle)) {
915 err = PTR_ERR(handle);
916 ext3_warning(sb, __FUNCTION__, "error %d on journal start",err);
921 if (o_blocks_count != le32_to_cpu(es->s_blocks_count)) {
922 ext3_warning(sb, __FUNCTION__,
923 "multiple resizers run on filesystem!\n");
928 if ((err = ext3_journal_get_write_access(handle,
929 EXT3_SB(sb)->s_sbh))) {
930 ext3_warning(sb, __FUNCTION__,
931 "error %d on journal write access", err);
933 ext3_journal_stop(handle);
936 es->s_blocks_count = cpu_to_le32(o_blocks_count + add);
937 ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
940 ext3_debug("freeing blocks %ld through %ld\n", o_blocks_count,
941 o_blocks_count + add);
942 ext3_free_blocks(handle, inode, o_blocks_count, add);
943 ext3_debug("freed blocks %ld through %ld\n", o_blocks_count,
944 o_blocks_count + add);
945 if ((err = ext3_journal_stop(handle)))
947 if (test_opt(sb, DEBUG))
948 printk("EXT3-fs: extended group to %u blocks\n",
949 le32_to_cpu(es->s_blocks_count));
950 update_backups(sb, inode, EXT3_SB(sb)->s_sbh->b_blocknr, (char *)es,
951 sizeof(struct ext3_super_block));
956 } /* ext3_group_extend */