2 * resize2fs.c --- ext2 main routine
4 * Copyright (C) 1997, 1998 by Theodore Ts'o and
7 * Copyright (C) 1999, 2000 by Theosore Ts'o
10 * This file may be redistributed under the terms of the GNU Public
16 * Resizing a filesystem consists of the following phases:
18 * 1. Adjust superblock and write out new parts of the inode
20 * 2. Determine blocks which need to be relocated, and copy the
21 * contents of blocks from their old locations to the new ones.
22 * 3. Scan the inode table, doing the following:
23 * a. If blocks have been moved, update the block
24 * pointers in the inodes and indirect blocks to
25 * point at the new block locations.
26 * b. If parts of the inode table need to be evacuated,
27 * copy inodes from their old locations to their
29 * c. If (b) needs to be done, note which blocks contain
30 * directory information, since we will need to
31 * update the directory information.
32 * 4. Update the directory blocks with the new inode locations.
33 * 5. Move the inode tables, if necessary.
37 #include "resize2fs.h"
40 #ifdef __linux__ /* Kludge for debugging */
41 #define RESIZE2FS_DEBUG
44 static void fix_uninit_block_bitmaps(ext2_filsys fs);
45 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
46 static errcode_t blocks_to_move(ext2_resize_t rfs);
47 static errcode_t block_mover(ext2_resize_t rfs);
48 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
49 static errcode_t inode_ref_fix(ext2_resize_t rfs);
50 static errcode_t move_itables(ext2_resize_t rfs);
51 static errcode_t fix_resize_inode(ext2_filsys fs);
52 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
53 static errcode_t fix_sb_journal_backup(ext2_filsys fs);
54 static errcode_t mark_table_blocks(ext2_filsys fs,
55 ext2fs_block_bitmap bmap);
56 static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs);
57 static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
58 ext2fs_block_bitmap meta_bmap);
61 * Some helper CPP macros
63 #define IS_BLOCK_BM(fs, i, blk) ((blk) == ext2fs_block_bitmap_loc((fs),(i)))
64 #define IS_INODE_BM(fs, i, blk) ((blk) == ext2fs_inode_bitmap_loc((fs),(i)))
66 #define IS_INODE_TB(fs, i, blk) (((blk) >= ext2fs_inode_table_loc((fs), (i))) && \
67 ((blk) < (ext2fs_inode_table_loc((fs), (i)) + \
68 (fs)->inode_blocks_per_group)))
70 /* Some bigalloc helper macros which are more succint... */
71 #define B2C(x) EXT2FS_B2C(fs, (x))
72 #define C2B(x) EXT2FS_C2B(fs, (x))
73 #define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
74 #define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
75 #define LT_CLSTR(x, y) (B2C(x) < B2C(y))
76 #define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
77 #define GT_CLSTR(x, y) (B2C(x) > B2C(y))
79 static int lazy_itable_init;
82 * This is the top-level routine which does the dirty deed....
84 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
85 errcode_t (*progress)(ext2_resize_t rfs, int pass,
87 unsigned long max_val))
91 struct resource_track rtrack, overall_track;
94 * Create the data structure
96 retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
100 memset(rfs, 0, sizeof(struct ext2_resize_struct));
105 rfs->progress = progress;
107 init_resource_track(&overall_track, "overall resize2fs", fs->io);
108 init_resource_track(&rtrack, "read_bitmaps", fs->io);
109 retval = ext2fs_read_bitmaps(fs);
112 print_resource_track(rfs, &rtrack, fs->io);
114 fs->super->s_state |= EXT2_ERROR_FS;
115 ext2fs_mark_super_dirty(fs);
118 init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
119 fix_uninit_block_bitmaps(fs);
120 print_resource_track(rfs, &rtrack, fs->io);
121 retval = ext2fs_dup_handle(fs, &rfs->new_fs);
125 init_resource_track(&rtrack, "adjust_superblock", fs->io);
126 retval = adjust_superblock(rfs, *new_size);
129 print_resource_track(rfs, &rtrack, fs->io);
132 init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
133 fix_uninit_block_bitmaps(rfs->new_fs);
134 print_resource_track(rfs, &rtrack, fs->io);
135 /* Clear the block bitmap uninit flag for the last block group */
136 ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
137 EXT2_BG_BLOCK_UNINIT);
139 *new_size = ext2fs_blocks_count(rfs->new_fs->super);
141 init_resource_track(&rtrack, "blocks_to_move", fs->io);
142 retval = blocks_to_move(rfs);
145 print_resource_track(rfs, &rtrack, fs->io);
147 #ifdef RESIZE2FS_DEBUG
148 if (rfs->flags & RESIZE_DEBUG_BMOVE)
149 printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
150 ext2fs_free_blocks_count(rfs->old_fs->super),
151 ext2fs_free_blocks_count(rfs->new_fs->super),
155 init_resource_track(&rtrack, "block_mover", fs->io);
156 retval = block_mover(rfs);
159 print_resource_track(rfs, &rtrack, fs->io);
161 init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
162 retval = inode_scan_and_fix(rfs);
165 print_resource_track(rfs, &rtrack, fs->io);
167 init_resource_track(&rtrack, "inode_ref_fix", fs->io);
168 retval = inode_ref_fix(rfs);
171 print_resource_track(rfs, &rtrack, fs->io);
173 init_resource_track(&rtrack, "move_itables", fs->io);
174 retval = move_itables(rfs);
177 print_resource_track(rfs, &rtrack, fs->io);
179 init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
180 retval = ext2fs_calculate_summary_stats(rfs->new_fs);
183 print_resource_track(rfs, &rtrack, fs->io);
185 init_resource_track(&rtrack, "fix_resize_inode", fs->io);
186 retval = fix_resize_inode(rfs->new_fs);
189 print_resource_track(rfs, &rtrack, fs->io);
191 init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
192 retval = fix_sb_journal_backup(rfs->new_fs);
195 print_resource_track(rfs, &rtrack, fs->io);
197 retval = clear_sparse_super2_last_group(rfs);
201 rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
202 rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
204 print_resource_track(rfs, &overall_track, fs->io);
205 retval = ext2fs_close_free(&rfs->new_fs);
211 ext2fs_free(rfs->old_fs);
214 ext2fs_free_mem(&rfs->itable_buf);
215 if (rfs->reserve_blocks)
216 ext2fs_free_block_bitmap(rfs->reserve_blocks);
217 if (rfs->move_blocks)
218 ext2fs_free_block_bitmap(rfs->move_blocks);
219 ext2fs_free_mem(&rfs);
225 ext2fs_free(rfs->new_fs);
229 ext2fs_free_mem(&rfs->itable_buf);
230 ext2fs_free_mem(&rfs);
235 * Clean up the bitmaps for unitialized bitmaps
237 static void fix_uninit_block_bitmaps(ext2_filsys fs)
243 if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
244 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
247 for (g=0; g < fs->group_desc_count; g++) {
248 if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
251 blk = ext2fs_group_first_block2(fs, g);
252 lblk = ext2fs_group_last_block2(fs, g);
253 ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
256 ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
257 ext2fs_mark_block_bitmap2(fs->block_map,
258 ext2fs_block_bitmap_loc(fs, g));
259 ext2fs_mark_block_bitmap2(fs->block_map,
260 ext2fs_inode_bitmap_loc(fs, g));
261 for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
262 i < (unsigned int) fs->inode_blocks_per_group;
264 ext2fs_mark_block_bitmap2(fs->block_map, blk);
268 /* --------------------------------------------------------------------
270 * Resize processing, phase 1.
272 * In this phase we adjust the in-memory superblock information, and
273 * initialize any new parts of the inode table. The new parts of the
274 * inode table are created in virgin disk space, so we can abort here
275 * without any side effects.
276 * --------------------------------------------------------------------
280 * If the group descriptor's bitmap and inode table blocks are valid,
281 * release them in the new filesystem data structure, and mark them as
282 * reserved so the old inode table blocks don't get overwritten.
284 static errcode_t free_gdp_blocks(ext2_filsys fs,
285 ext2fs_block_bitmap reserve_blocks,
292 ext2fs_block_bitmap bg_map = NULL;
293 errcode_t retval = 0;
294 dgrp_t count = old_fs->group_desc_count - fs->group_desc_count;
296 /* If bigalloc, don't free metadata living in the same cluster */
297 if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
298 retval = ext2fs_allocate_block_bitmap(fs, "bgdata", &bg_map);
302 retval = mark_table_blocks(fs, bg_map);
307 for (i = group; i < group + count; i++) {
308 blk = ext2fs_block_bitmap_loc(old_fs, i);
310 (blk < ext2fs_blocks_count(fs->super)) &&
311 !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
312 ext2fs_block_alloc_stats2(fs, blk, -1);
313 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
316 blk = ext2fs_inode_bitmap_loc(old_fs, i);
318 (blk < ext2fs_blocks_count(fs->super)) &&
319 !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
320 ext2fs_block_alloc_stats2(fs, blk, -1);
321 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
324 blk = ext2fs_inode_table_loc(old_fs, i);
326 j < fs->inode_blocks_per_group; j++, blk++) {
327 if (blk >= ext2fs_blocks_count(fs->super) ||
328 (bg_map && ext2fs_test_block_bitmap2(bg_map, blk)))
330 ext2fs_block_alloc_stats2(fs, blk, -1);
331 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
337 ext2fs_free_block_bitmap(bg_map);
342 * This routine is shared by the online and offline resize routines.
343 * All of the information which is adjusted in memory is done here.
345 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
346 ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
349 blk64_t overhead = 0;
351 blk64_t blk, group_block;
353 blk64_t old_numblocks, numblocks, adjblocks;
354 unsigned long i, j, old_desc_blocks;
355 unsigned int meta_bg, meta_bg_size;
356 int has_super, csum_flag;
357 unsigned long long new_inodes; /* u64 to check for overflow */
360 ext2fs_blocks_count_set(fs->super, new_size);
363 fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
364 fs->super->s_first_data_block,
365 EXT2_BLOCKS_PER_GROUP(fs->super));
366 if (fs->group_desc_count == 0)
367 return EXT2_ET_TOOSMALL;
368 fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
369 EXT2_DESC_PER_BLOCK(fs->super));
372 * Overhead is the number of bookkeeping blocks per group. It
373 * includes the superblock backup, the group descriptor
374 * backups, the inode bitmap, the block bitmap, and the inode
377 overhead = (int) (2 + fs->inode_blocks_per_group);
379 if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
380 overhead += 1 + fs->desc_blocks +
381 fs->super->s_reserved_gdt_blocks;
384 * See if the last group is big enough to support the
385 * necessary data structures. If not, we need to get rid of
388 rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
389 fs->super->s_blocks_per_group;
390 if ((fs->group_desc_count == 1) && rem && (rem < overhead))
391 return EXT2_ET_TOOSMALL;
392 if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
393 ext2fs_blocks_count_set(fs->super,
394 ext2fs_blocks_count(fs->super) - rem);
398 * Adjust the number of inodes
400 new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
401 if (new_inodes > ~0U) {
402 fprintf(stderr, _("inodes (%llu) must be less than %u"),
404 return EXT2_ET_TOO_MANY_INODES;
406 fs->super->s_inodes_count = fs->super->s_inodes_per_group *
407 fs->group_desc_count;
410 * Adjust the number of free blocks
412 blk = ext2fs_blocks_count(old_fs->super);
413 if (blk > ext2fs_blocks_count(fs->super))
414 ext2fs_free_blocks_count_set(fs->super,
415 ext2fs_free_blocks_count(fs->super) -
416 (blk - ext2fs_blocks_count(fs->super)));
418 ext2fs_free_blocks_count_set(fs->super,
419 ext2fs_free_blocks_count(fs->super) +
420 (ext2fs_blocks_count(fs->super) - blk));
423 * Adjust the number of reserved blocks
425 percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
426 ext2fs_blocks_count(old_fs->super);
427 ext2fs_r_blocks_count_set(fs->super,
428 (percent * ext2fs_blocks_count(fs->super) /
432 * Adjust the bitmaps for size
434 retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
435 fs->super->s_inodes_count,
437 if (retval) goto errout;
439 real_end = EXT2_GROUPS_TO_BLOCKS(fs->super, fs->group_desc_count) - 1 +
440 fs->super->s_first_data_block;
441 retval = ext2fs_resize_block_bitmap2(new_size - 1,
442 real_end, fs->block_map);
443 if (retval) goto errout;
446 * If we are growing the file system, also grow the size of
447 * the reserve_blocks bitmap
449 if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
450 retval = ext2fs_resize_block_bitmap2(new_size - 1,
451 real_end, reserve_blocks);
452 if (retval) goto errout;
456 * Reallocate the group descriptors as necessary.
458 if (old_fs->desc_blocks != fs->desc_blocks) {
459 retval = ext2fs_resize_mem(old_fs->desc_blocks *
461 fs->desc_blocks * fs->blocksize,
465 if (fs->desc_blocks > old_fs->desc_blocks)
466 memset((char *) fs->group_desc +
467 (old_fs->desc_blocks * fs->blocksize), 0,
468 (fs->desc_blocks - old_fs->desc_blocks) *
473 * If the resize_inode feature is set, and we are changing the
474 * number of descriptor blocks, then adjust
475 * s_reserved_gdt_blocks if possible to avoid needing to move
476 * the inode table either now or in the future.
478 if ((fs->super->s_feature_compat &
479 EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
480 (old_fs->desc_blocks != fs->desc_blocks)) {
483 new = ((int) fs->super->s_reserved_gdt_blocks) +
484 (old_fs->desc_blocks - fs->desc_blocks);
487 if (new > (int) fs->blocksize/4)
488 new = fs->blocksize/4;
489 fs->super->s_reserved_gdt_blocks = new;
492 if ((fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) &&
493 (fs->super->s_first_meta_bg > fs->desc_blocks)) {
494 fs->super->s_feature_incompat &=
495 ~EXT2_FEATURE_INCOMPAT_META_BG;
496 fs->super->s_first_meta_bg = 0;
500 * Update the location of the backup superblocks if the
501 * sparse_super2 feature is enabled.
503 if (fs->super->s_feature_compat & EXT4_FEATURE_COMPAT_SPARSE_SUPER2) {
504 dgrp_t last_bg = fs->group_desc_count - 1;
505 dgrp_t old_last_bg = old_fs->group_desc_count - 1;
507 if (last_bg > old_last_bg) {
508 if (old_fs->group_desc_count == 1)
509 fs->super->s_backup_bgs[0] = 1;
510 if (old_fs->group_desc_count == 1 &&
511 fs->super->s_backup_bgs[0])
512 fs->super->s_backup_bgs[0] = last_bg;
513 else if (fs->super->s_backup_bgs[1])
514 fs->super->s_backup_bgs[1] = last_bg;
515 } else if (last_bg < old_last_bg) {
516 if (fs->super->s_backup_bgs[0] > last_bg)
517 fs->super->s_backup_bgs[0] = 0;
518 if (fs->super->s_backup_bgs[1] > last_bg)
519 fs->super->s_backup_bgs[1] = 0;
521 old_fs->super->s_backup_bgs[1] == old_last_bg)
522 fs->super->s_backup_bgs[1] = last_bg;
527 * If we are shrinking the number of block groups, we're done
530 if (old_fs->group_desc_count > fs->group_desc_count) {
532 * Check the block groups that we are chopping off
533 * and free any blocks associated with their metadata
535 retval = free_gdp_blocks(fs, reserve_blocks, old_fs,
536 fs->group_desc_count);
541 * Fix the count of the last (old) block group
543 old_numblocks = (ext2fs_blocks_count(old_fs->super) -
544 old_fs->super->s_first_data_block) %
545 old_fs->super->s_blocks_per_group;
547 old_numblocks = old_fs->super->s_blocks_per_group;
548 if (old_fs->group_desc_count == fs->group_desc_count) {
549 numblocks = (ext2fs_blocks_count(fs->super) -
550 fs->super->s_first_data_block) %
551 fs->super->s_blocks_per_group;
553 numblocks = fs->super->s_blocks_per_group;
555 numblocks = fs->super->s_blocks_per_group;
556 i = old_fs->group_desc_count - 1;
557 ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
558 ext2fs_group_desc_csum_set(fs, i);
561 * If the number of block groups is staying the same, we're
562 * done and can exit now. (If the number block groups is
563 * shrinking, we had exited earlier.)
565 if (old_fs->group_desc_count >= fs->group_desc_count) {
571 * Initialize the new block group descriptors
573 group_block = ext2fs_group_first_block2(fs,
574 old_fs->group_desc_count);
575 csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
576 EXT4_FEATURE_RO_COMPAT_GDT_CSUM);
577 if (access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0)
578 lazy_itable_init = 1;
579 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
580 old_desc_blocks = fs->super->s_first_meta_bg;
582 old_desc_blocks = fs->desc_blocks +
583 fs->super->s_reserved_gdt_blocks;
586 * If we changed the number of block_group descriptor blocks,
587 * we need to make sure they are all marked as reserved in the
588 * file systems's block allocation map.
590 for (i = 0; i < old_fs->group_desc_count; i++)
591 ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
593 for (i = old_fs->group_desc_count;
594 i < fs->group_desc_count; i++) {
595 memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
596 sizeof(struct ext2_group_desc));
599 ext2fs_bg_flags_zap(fs, i);
601 ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
602 if (!lazy_itable_init)
603 ext2fs_bg_flags_set(fs, i,
604 EXT2_BG_INODE_ZEROED);
605 ext2fs_bg_itable_unused_set(fs, i,
606 fs->super->s_inodes_per_group);
609 numblocks = ext2fs_group_blocks_count(fs, i);
610 if ((i < fs->group_desc_count - 1) && csum_flag)
611 ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
613 has_super = ext2fs_bg_has_super(fs, i);
615 ext2fs_block_alloc_stats2(fs, group_block, +1);
618 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
619 meta_bg = i / meta_bg_size;
620 if (!(fs->super->s_feature_incompat &
621 EXT2_FEATURE_INCOMPAT_META_BG) ||
622 (meta_bg < fs->super->s_first_meta_bg)) {
624 for (j=0; j < old_desc_blocks; j++)
625 ext2fs_block_alloc_stats2(fs,
626 group_block + 1 + j, +1);
627 adjblocks += old_desc_blocks;
632 if (((i % meta_bg_size) == 0) ||
633 ((i % meta_bg_size) == 1) ||
634 ((i % meta_bg_size) == (meta_bg_size-1)))
635 ext2fs_block_alloc_stats2(fs,
636 group_block + has_super, +1);
639 adjblocks += 2 + fs->inode_blocks_per_group;
641 numblocks -= adjblocks;
642 ext2fs_free_blocks_count_set(fs->super,
643 ext2fs_free_blocks_count(fs->super) - adjblocks);
644 fs->super->s_free_inodes_count +=
645 fs->super->s_inodes_per_group;
646 ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
647 ext2fs_bg_free_inodes_count_set(fs, i,
648 fs->super->s_inodes_per_group);
649 ext2fs_bg_used_dirs_count_set(fs, i, 0);
650 ext2fs_group_desc_csum_set(fs, i);
652 retval = ext2fs_allocate_group_table(fs, i, 0);
653 if (retval) goto errout;
655 group_block += fs->super->s_blocks_per_group;
660 * Mark all of the metadata blocks as reserved so they won't
661 * get allocated by the call to ext2fs_allocate_group_table()
662 * in blocks_to_move(), where we allocate new blocks to
663 * replace those allocation bitmap and inode table blocks
664 * which have to get relocated to make space for an increased
665 * number of the block group descriptors.
668 mark_table_blocks(fs, reserve_blocks);
675 * This routine adjusts the superblock and other data structures, both
676 * in disk as well as in memory...
678 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
680 ext2_filsys fs = rfs->new_fs;
685 unsigned long max_group;
687 ext2fs_mark_super_dirty(fs);
688 ext2fs_mark_bb_dirty(fs);
689 ext2fs_mark_ib_dirty(fs);
691 retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
692 &rfs->reserve_blocks);
696 retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
701 * Check to make sure there are enough inodes
703 if ((rfs->old_fs->super->s_inodes_count -
704 rfs->old_fs->super->s_free_inodes_count) >
705 rfs->new_fs->super->s_inodes_count) {
711 * If we are shrinking the number block groups, we're done and
714 if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
720 * If the number of block groups is staying the same, we're
721 * done and can exit now. (If the number block groups is
722 * shrinking, we had exited earlier.)
724 if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
730 * If we are using uninit_bg (aka GDT_CSUM) and the kernel
731 * supports lazy inode initialization, we can skip
732 * initializing the inode table.
734 if (lazy_itable_init &&
735 EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
736 EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
742 * Initialize the inode table
744 retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
749 memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
750 group_block = ext2fs_group_first_block2(fs,
751 rfs->old_fs->group_desc_count);
752 adj = rfs->old_fs->group_desc_count;
753 max_group = fs->group_desc_count - adj;
755 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
760 for (i = rfs->old_fs->group_desc_count;
761 i < fs->group_desc_count; i++) {
763 * Write out the new inode table
765 retval = io_channel_write_blk64(fs->io,
766 ext2fs_inode_table_loc(fs, i),
767 fs->inode_blocks_per_group,
769 if (retval) goto errout;
771 io_channel_flush(fs->io);
773 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
774 i - adj + 1, max_group);
778 group_block += fs->super->s_blocks_per_group;
780 io_channel_flush(fs->io);
787 /* --------------------------------------------------------------------
789 * Resize processing, phase 2.
791 * In this phase we adjust determine which blocks need to be moved, in
792 * blocks_to_move(). We then copy the blocks to their ultimate new
793 * destinations using block_mover(). Since we are copying blocks to
794 * their new locations, again during this pass we can abort without
796 * --------------------------------------------------------------------
800 * This helper function creates a block bitmap with all of the
801 * filesystem meta-data blocks.
803 static errcode_t mark_table_blocks(ext2_filsys fs,
804 ext2fs_block_bitmap bmap)
809 for (i = 0; i < fs->group_desc_count; i++) {
810 ext2fs_reserve_super_and_bgd(fs, i, bmap);
813 * Mark the blocks used for the inode table
815 blk = ext2fs_inode_table_loc(fs, i);
817 ext2fs_mark_block_bitmap_range2(bmap, blk,
818 fs->inode_blocks_per_group);
821 * Mark block used for the block bitmap
823 blk = ext2fs_block_bitmap_loc(fs, i);
825 ext2fs_mark_block_bitmap2(bmap, blk);
828 * Mark block used for the inode bitmap
830 blk = ext2fs_inode_bitmap_loc(fs, i);
832 ext2fs_mark_block_bitmap2(bmap, blk);
838 * This function checks to see if a particular block (either a
839 * superblock or a block group descriptor) overlaps with an inode or
840 * block bitmap block, or with the inode table.
842 static void mark_fs_metablock(ext2_resize_t rfs,
843 ext2fs_block_bitmap meta_bmap,
844 int group, blk64_t blk)
846 ext2_filsys fs = rfs->new_fs;
848 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
849 ext2fs_block_alloc_stats2(fs, blk, +1);
852 * Check to see if we overlap with the inode or block bitmap,
853 * or the inode tables. If not, and the block is in use, then
854 * mark it as a block to be moved.
856 if (IS_BLOCK_BM(fs, group, blk)) {
857 ext2fs_block_bitmap_loc_set(fs, group, 0);
858 rfs->needed_blocks++;
861 if (IS_INODE_BM(fs, group, blk)) {
862 ext2fs_inode_bitmap_loc_set(fs, group, 0);
863 rfs->needed_blocks++;
866 if (IS_INODE_TB(fs, group, blk)) {
867 ext2fs_inode_table_loc_set(fs, group, 0);
868 rfs->needed_blocks++;
871 if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
874 for (i=0; i < rfs->old_fs->group_desc_count; i++) {
875 if (IS_BLOCK_BM(fs, i, blk)) {
876 ext2fs_block_bitmap_loc_set(fs, i, 0);
877 rfs->needed_blocks++;
880 if (IS_INODE_BM(fs, i, blk)) {
881 ext2fs_inode_bitmap_loc_set(fs, i, 0);
882 rfs->needed_blocks++;
885 if (IS_INODE_TB(fs, i, blk)) {
886 ext2fs_inode_table_loc_set(fs, i, 0);
887 rfs->needed_blocks++;
892 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
893 EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
894 (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
896 * If the block bitmap is uninitialized, which means
897 * nothing other than standard metadata in use.
900 } else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
901 !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
902 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
903 rfs->needed_blocks++;
909 * This routine marks and unmarks reserved blocks in the new block
910 * bitmap. It also determines which blocks need to be moved and
911 * places this information into the move_blocks bitmap.
913 static errcode_t blocks_to_move(ext2_resize_t rfs)
916 dgrp_t i, max_groups, g;
917 blk64_t blk, group_blk;
918 blk64_t old_blocks, new_blocks, group_end, cluster_freed;
920 unsigned int meta_bg, meta_bg_size;
922 ext2_filsys fs, old_fs;
923 ext2fs_block_bitmap meta_bmap, new_meta_bmap = NULL;
927 old_fs = rfs->old_fs;
928 if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
931 retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
936 retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
941 retval = mark_table_blocks(old_fs, meta_bmap);
948 * If we're shrinking the filesystem, we need to move any
949 * group's metadata blocks (either allocation bitmaps or the
950 * inode table) which are beyond the end of the new
953 new_size = ext2fs_blocks_count(fs->super);
954 if (new_size < ext2fs_blocks_count(old_fs->super)) {
955 for (g = 0; g < fs->group_desc_count; g++) {
958 * ext2fs_allocate_group_table will re-allocate any
959 * metadata blocks whose location is set to zero.
961 if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
962 ext2fs_block_bitmap_loc_set(fs, g, 0);
965 if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
966 ext2fs_inode_bitmap_loc_set(fs, g, 0);
969 if ((ext2fs_inode_table_loc(fs, g) +
970 fs->inode_blocks_per_group) > new_size) {
971 ext2fs_inode_table_loc_set(fs, g, 0);
976 retval = ext2fs_allocate_group_table(fs, g, 0);
984 * If we're shrinking the filesystem, we need to move all of
985 * the blocks that don't fit any more
987 for (blk = ext2fs_blocks_count(fs->super);
988 blk < ext2fs_blocks_count(old_fs->super); blk++) {
989 g = ext2fs_group_of_blk2(fs, blk);
990 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
991 EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
992 ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
994 * The block bitmap is uninitialized, so skip
995 * to the next block group.
997 blk = ext2fs_group_first_block2(fs, g+1) - 1;
1000 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1001 !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
1002 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
1003 rfs->needed_blocks++;
1005 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1008 if (old_fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1009 old_blocks = old_fs->super->s_first_meta_bg;
1011 old_blocks = old_fs->desc_blocks +
1012 old_fs->super->s_reserved_gdt_blocks;
1013 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1014 new_blocks = fs->super->s_first_meta_bg;
1016 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
1018 retval = reserve_sparse_super2_last_group(rfs, meta_bmap);
1022 if (old_blocks == new_blocks) {
1027 max_groups = fs->group_desc_count;
1028 if (max_groups > old_fs->group_desc_count)
1029 max_groups = old_fs->group_desc_count;
1030 group_blk = old_fs->super->s_first_data_block;
1032 * If we're reducing the number of descriptor blocks, this
1033 * makes life easy. :-) We just have to mark some extra
1036 if (old_blocks > new_blocks) {
1037 if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
1038 retval = ext2fs_allocate_block_bitmap(fs,
1039 _("new meta blocks"),
1044 retval = mark_table_blocks(fs, new_meta_bmap);
1049 for (i = 0; i < max_groups; i++) {
1050 if (!ext2fs_bg_has_super(fs, i)) {
1051 group_blk += fs->super->s_blocks_per_group;
1054 group_end = group_blk + 1 + old_blocks;
1055 for (blk = group_blk + 1 + new_blocks;
1057 if (new_meta_bmap == NULL ||
1058 !ext2fs_test_block_bitmap2(new_meta_bmap,
1061 EXT2FS_CLUSTER_RATIO(fs) -
1063 EXT2FS_CLUSTER_MASK(fs));
1064 if (cluster_freed > group_end - blk)
1065 cluster_freed = group_end - blk;
1066 ext2fs_block_alloc_stats2(fs, blk, -1);
1067 blk += EXT2FS_CLUSTER_RATIO(fs);
1068 rfs->needed_blocks -= cluster_freed;
1071 rfs->needed_blocks--;
1074 group_blk += fs->super->s_blocks_per_group;
1080 * If we're increasing the number of descriptor blocks, life
1081 * gets interesting....
1083 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
1084 flex_bg = fs->super->s_feature_incompat &
1085 EXT4_FEATURE_INCOMPAT_FLEX_BG;
1086 /* first reserve all of the existing fs meta blocks */
1087 for (i = 0; i < max_groups; i++) {
1088 has_super = ext2fs_bg_has_super(fs, i);
1090 mark_fs_metablock(rfs, meta_bmap, i, group_blk);
1092 meta_bg = i / meta_bg_size;
1093 if (!(fs->super->s_feature_incompat &
1094 EXT2_FEATURE_INCOMPAT_META_BG) ||
1095 (meta_bg < fs->super->s_first_meta_bg)) {
1097 for (blk = group_blk+1;
1098 blk < group_blk + 1 + new_blocks; blk++)
1099 mark_fs_metablock(rfs, meta_bmap,
1105 if (((i % meta_bg_size) == 0) ||
1106 ((i % meta_bg_size) == 1) ||
1107 ((i % meta_bg_size) == (meta_bg_size-1)))
1108 mark_fs_metablock(rfs, meta_bmap, i,
1109 group_blk + has_super);
1113 * Reserve the existing meta blocks that we know
1114 * aren't to be moved.
1116 * For flex_bg file systems, in order to avoid
1117 * overwriting fs metadata (especially inode table
1118 * blocks) belonging to a different block group when
1119 * we are relocating the inode tables, we need to
1120 * reserve all existing fs metadata blocks.
1122 if (ext2fs_block_bitmap_loc(fs, i))
1123 ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1124 ext2fs_block_bitmap_loc(fs, i));
1125 else if (flex_bg && i < old_fs->group_desc_count)
1126 ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1127 ext2fs_block_bitmap_loc(old_fs, i));
1129 if (ext2fs_inode_bitmap_loc(fs, i))
1130 ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1131 ext2fs_inode_bitmap_loc(fs, i));
1132 else if (flex_bg && i < old_fs->group_desc_count)
1133 ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1134 ext2fs_inode_bitmap_loc(old_fs, i));
1136 if (ext2fs_inode_table_loc(fs, i))
1137 ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1138 ext2fs_inode_table_loc(fs, i),
1139 fs->inode_blocks_per_group);
1140 else if (flex_bg && i < old_fs->group_desc_count)
1141 ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1142 ext2fs_inode_table_loc(old_fs, i),
1143 old_fs->inode_blocks_per_group);
1145 group_blk += rfs->new_fs->super->s_blocks_per_group;
1148 /* Allocate the missing data structures */
1149 for (i = 0; i < max_groups; i++) {
1150 if (ext2fs_inode_table_loc(fs, i) &&
1151 ext2fs_inode_bitmap_loc(fs, i) &&
1152 ext2fs_block_bitmap_loc(fs, i))
1155 retval = ext2fs_allocate_group_table(fs, i,
1156 rfs->reserve_blocks);
1161 * For those structures that have changed, we need to
1164 if (ext2fs_block_bitmap_loc(old_fs, i) !=
1165 (blk = ext2fs_block_bitmap_loc(fs, i))) {
1166 ext2fs_block_alloc_stats2(fs, blk, +1);
1167 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1168 !ext2fs_test_block_bitmap2(meta_bmap, blk))
1169 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1172 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1173 (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1174 ext2fs_block_alloc_stats2(fs, blk, +1);
1175 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1176 !ext2fs_test_block_bitmap2(meta_bmap, blk))
1177 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1182 * The inode table, if we need to relocate it, is
1183 * handled specially. We have to reserve the blocks
1184 * for both the old and the new inode table, since we
1185 * can't have the inode table be destroyed during the
1186 * block relocation phase.
1188 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1189 continue; /* inode table not moved */
1191 rfs->needed_blocks += fs->inode_blocks_per_group;
1194 * Mark the new inode table as in use in the new block
1195 * allocation bitmap, and move any blocks that might
1198 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1199 j < fs->inode_blocks_per_group ; j++, blk++) {
1200 ext2fs_block_alloc_stats2(fs, blk, +1);
1201 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1202 !ext2fs_test_block_bitmap2(meta_bmap, blk))
1203 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1208 * Make sure the old inode table is reserved in the
1209 * block reservation bitmap.
1211 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1212 j < fs->inode_blocks_per_group ; j++, blk++)
1213 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1219 ext2fs_free_block_bitmap(new_meta_bmap);
1221 ext2fs_free_block_bitmap(meta_bmap);
1227 * This helper function tries to allocate a new block. We try to
1228 * avoid hitting the original group descriptor blocks at least at
1229 * first, since we want to make it possible to recover from a badly
1230 * aborted resize operation as much as possible.
1232 * In the future, I may further modify this routine to balance out
1233 * where we get the new blocks across the various block groups.
1234 * Ideally we would allocate blocks that corresponded with the block
1235 * group of the containing inode, and keep contiguous blocks
1236 * together. However, this very difficult to do efficiently, since we
1237 * don't have the necessary information up front.
1241 #define DESPERATION 2
1243 static void init_block_alloc(ext2_resize_t rfs)
1245 rfs->alloc_state = AVOID_OLD;
1246 rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1248 /* HACK for testing */
1249 if (ext2fs_blocks_count(rfs->new_fs->super) >
1250 ext2fs_blocks_count(rfs->old_fs->super))
1251 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1255 static blk64_t get_new_block(ext2_resize_t rfs)
1257 ext2_filsys fs = rfs->new_fs;
1260 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1261 if (rfs->alloc_state == DESPERATION)
1264 #ifdef RESIZE2FS_DEBUG
1265 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1266 printf("Going into desperation mode "
1267 "for block allocations\n");
1269 rfs->alloc_state = DESPERATION;
1270 rfs->new_blk = fs->super->s_first_data_block;
1273 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1274 ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1276 ((rfs->alloc_state == AVOID_OLD) &&
1277 (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1278 ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1283 return rfs->new_blk;
1287 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
1290 ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1293 blk = get_new_block(rfs);
1297 #ifdef RESIZE2FS_DEBUG
1298 if (rfs->flags & 0xF)
1299 printf("get_alloc_block allocating %llu\n", blk);
1302 ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1303 ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1304 *ret = (blk64_t) blk;
1308 static errcode_t block_mover(ext2_resize_t rfs)
1310 blk64_t blk, old_blk, new_blk;
1311 ext2_filsys fs = rfs->new_fs;
1312 ext2_filsys old_fs = rfs->old_fs;
1317 ext2_badblocks_list badblock_list = 0;
1318 int bb_modified = 0;
1320 fs->get_alloc_block = resize2fs_get_alloc_block;
1321 old_fs->get_alloc_block = resize2fs_get_alloc_block;
1323 retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1327 new_blk = fs->super->s_first_data_block;
1328 if (!rfs->itable_buf) {
1329 retval = ext2fs_get_array(fs->blocksize,
1330 fs->inode_blocks_per_group,
1335 retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1340 * The first step is to figure out where all of the blocks
1343 to_move = moved = 0;
1344 init_block_alloc(rfs);
1345 for (blk = B2C(old_fs->super->s_first_data_block);
1346 blk < ext2fs_blocks_count(old_fs->super);
1347 blk += EXT2FS_CLUSTER_RATIO(fs)) {
1348 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1350 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1352 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1353 ext2fs_badblocks_list_del(badblock_list, blk);
1358 new_blk = get_new_block(rfs);
1363 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1364 ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1370 ext2fs_free_extent_table(rfs->bmap);
1378 * Step two is to actually move the blocks
1380 retval = ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1381 if (retval) goto errout;
1383 if (rfs->progress) {
1384 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1390 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1391 if (retval) goto errout;
1394 old_blk = C2B(old_blk);
1395 new_blk = C2B(new_blk);
1397 #ifdef RESIZE2FS_DEBUG
1398 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1399 printf("Moving %llu blocks %llu->%llu\n",
1400 size, old_blk, new_blk);
1404 if (c > fs->inode_blocks_per_group)
1405 c = fs->inode_blocks_per_group;
1406 retval = io_channel_read_blk64(fs->io, old_blk, c,
1408 if (retval) goto errout;
1409 retval = io_channel_write_blk64(fs->io, new_blk, c,
1411 if (retval) goto errout;
1416 if (rfs->progress) {
1417 io_channel_flush(fs->io);
1418 retval = (rfs->progress)(rfs,
1419 E2_RSZ_BLOCK_RELOC_PASS,
1425 io_channel_flush(fs->io);
1429 if (badblock_list) {
1430 if (!retval && bb_modified)
1431 retval = ext2fs_update_bb_inode(old_fs,
1433 ext2fs_badblocks_list_free(badblock_list);
1439 /* --------------------------------------------------------------------
1441 * Resize processing, phase 3
1443 * --------------------------------------------------------------------
1448 * The extent translation table is stored in clusters so we need to
1449 * take special care when mapping a source block number to its
1450 * destination block number.
1452 static __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1454 __u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1457 new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1461 struct process_block_struct {
1464 struct ext2_inode * inode;
1470 static int process_block(ext2_filsys fs, blk64_t *block_nr,
1471 e2_blkcnt_t blockcnt,
1472 blk64_t ref_block EXT2FS_ATTR((unused)),
1473 int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1475 struct process_block_struct *pb;
1477 blk64_t block, new_block;
1480 pb = (struct process_block_struct *) priv_data;
1482 if (pb->rfs->bmap) {
1483 new_block = extent_translate(fs, pb->rfs->bmap, block);
1485 *block_nr = new_block;
1486 ret |= BLOCK_CHANGED;
1488 #ifdef RESIZE2FS_DEBUG
1489 if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1490 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1491 pb->ino, blockcnt, block, new_block);
1497 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1498 block, (int) blockcnt);
1510 static errcode_t progress_callback(ext2_filsys fs,
1511 ext2_inode_scan scan EXT2FS_ATTR((unused)),
1512 dgrp_t group, void * priv_data)
1514 ext2_resize_t rfs = (ext2_resize_t) priv_data;
1518 * This check is to protect against old ext2 libraries. It
1519 * shouldn't be needed against new libraries.
1524 if (rfs->progress) {
1525 io_channel_flush(fs->io);
1526 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1527 group+1, fs->group_desc_count);
1535 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1537 struct process_block_struct pb;
1538 ext2_ino_t ino, new_inode;
1539 struct ext2_inode *inode = NULL;
1540 ext2_inode_scan scan = NULL;
1542 char *block_buf = 0;
1543 ext2_ino_t start_to_move;
1548 if ((rfs->old_fs->group_desc_count <=
1549 rfs->new_fs->group_desc_count) &&
1554 * Save the original size of the old filesystem, and
1555 * temporarily set the size to be the new size if the new size
1556 * is larger. We need to do this to avoid catching an error
1557 * by the block iterator routines
1559 orig_size = ext2fs_blocks_count(rfs->old_fs->super);
1560 if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
1561 ext2fs_blocks_count_set(rfs->old_fs->super,
1562 ext2fs_blocks_count(rfs->new_fs->super));
1564 retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1565 if (retval) goto errout;
1567 retval = ext2fs_init_dblist(rfs->old_fs, 0);
1568 if (retval) goto errout;
1569 retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
1570 if (retval) goto errout;
1572 start_to_move = (rfs->new_fs->group_desc_count *
1573 rfs->new_fs->super->s_inodes_per_group);
1575 if (rfs->progress) {
1576 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1577 0, rfs->old_fs->group_desc_count);
1581 ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1585 new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1586 inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
1587 inode = malloc(inode_size);
1593 * First, copy all of the inodes that need to be moved
1594 * elsewhere in the inode table
1597 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
1598 if (retval) goto errout;
1602 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
1603 continue; /* inode not in use */
1605 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
1608 if (ext2fs_file_acl_block(rfs->old_fs, inode) && rfs->bmap) {
1609 new_block = extent_translate(rfs->old_fs, rfs->bmap,
1610 ext2fs_file_acl_block(rfs->old_fs, inode));
1612 ext2fs_file_acl_block_set(rfs->old_fs, inode,
1614 retval = ext2fs_write_inode_full(rfs->old_fs,
1615 ino, inode, inode_size);
1616 if (retval) goto errout;
1620 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
1621 (rfs->bmap || pb.is_dir)) {
1623 retval = ext2fs_block_iterate3(rfs->old_fs,
1625 process_block, &pb);
1634 if (ino <= start_to_move)
1635 continue; /* Don't need to move it. */
1640 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
1644 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
1647 /* Get the new version of the inode */
1648 retval = ext2fs_read_inode_full(rfs->old_fs, ino,
1650 if (retval) goto errout;
1652 inode->i_ctime = time(0);
1653 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
1655 if (retval) goto errout;
1657 #ifdef RESIZE2FS_DEBUG
1658 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1659 printf("Inode moved %u->%u\n", ino, new_inode);
1662 retval = ext2fs_create_extent_table(&rfs->imap, 0);
1666 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1668 io_channel_flush(rfs->old_fs->io);
1671 ext2fs_blocks_count_set(rfs->old_fs->super, orig_size);
1673 ext2fs_free_extent_table(rfs->bmap);
1677 ext2fs_close_inode_scan(scan);
1679 ext2fs_free_mem(&block_buf);
1684 /* --------------------------------------------------------------------
1686 * Resize processing, phase 4.
1688 * --------------------------------------------------------------------
1694 unsigned int max_dirs;
1698 static int check_and_change_inodes(ext2_ino_t dir,
1699 int entry EXT2FS_ATTR((unused)),
1700 struct ext2_dir_entry *dirent, int offset,
1701 int blocksize EXT2FS_ATTR((unused)),
1702 char *buf EXT2FS_ATTR((unused)),
1705 struct istruct *is = (struct istruct *) priv_data;
1706 struct ext2_inode inode;
1707 ext2_ino_t new_inode;
1710 if (is->rfs->progress && offset == 0) {
1711 io_channel_flush(is->rfs->old_fs->io);
1712 is->err = (is->rfs->progress)(is->rfs,
1713 E2_RSZ_INODE_REF_UPD_PASS,
1714 ++is->num, is->max_dirs);
1716 return DIRENT_ABORT;
1722 new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1726 #ifdef RESIZE2FS_DEBUG
1727 if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1728 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1729 dir, dirent->name_len&0xFF, dirent->name,
1730 dirent->inode, new_inode);
1733 dirent->inode = new_inode;
1735 /* Update the directory mtime and ctime */
1736 retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1738 inode.i_mtime = inode.i_ctime = time(0);
1739 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1741 return DIRENT_ABORT;
1744 return DIRENT_CHANGED;
1747 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1756 * Now, we iterate over all of the directories to update the
1760 is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
1764 if (rfs->progress) {
1765 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1771 retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1772 DIRENT_FLAG_INCLUDE_EMPTY, 0,
1773 check_and_change_inodes, &is);
1781 if (rfs->progress && (is.num < is.max_dirs))
1782 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1783 is.max_dirs, is.max_dirs);
1786 ext2fs_free_extent_table(rfs->imap);
1792 /* --------------------------------------------------------------------
1794 * Resize processing, phase 5.
1796 * In this phase we actually move the inode table around, and then
1797 * update the summary statistics. This is scary, since aborting here
1798 * will potentially scramble the filesystem. (We are moving the
1799 * inode tables around in place, and so the potential for lost data,
1800 * or at the very least scrambling the mapping between filenames and
1801 * inode numbers is very high in case of a power failure here.)
1802 * --------------------------------------------------------------------
1807 * A very scary routine --- this one moves the inode table around!!!
1809 * After this you have to use the rfs->new_fs file handle to read and
1812 static errcode_t move_itables(ext2_resize_t rfs)
1816 dgrp_t i, max_groups;
1817 ext2_filsys fs = rfs->new_fs;
1819 blk64_t old_blk, new_blk, blk, cluster_freed;
1821 int j, to_move, moved;
1822 ext2fs_block_bitmap new_bmap = NULL;
1824 max_groups = fs->group_desc_count;
1825 if (max_groups > rfs->old_fs->group_desc_count)
1826 max_groups = rfs->old_fs->group_desc_count;
1828 size = fs->blocksize * fs->inode_blocks_per_group;
1829 if (!rfs->itable_buf) {
1830 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1835 if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
1836 retval = ext2fs_allocate_block_bitmap(fs, _("new meta blocks"),
1841 retval = mark_table_blocks(fs, new_bmap);
1847 * Figure out how many inode tables we need to move
1849 to_move = moved = 0;
1850 for (i=0; i < max_groups; i++)
1851 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
1852 ext2fs_inode_table_loc(fs, i))
1860 if (rfs->progress) {
1861 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1867 rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1869 for (i=0; i < max_groups; i++) {
1870 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
1871 new_blk = ext2fs_inode_table_loc(fs, i);
1872 diff = new_blk - old_blk;
1874 #ifdef RESIZE2FS_DEBUG
1875 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1876 printf("Itable move group %d block %llu->%llu (diff %lld)\n",
1877 i, old_blk, new_blk, diff);
1885 retval = io_channel_read_blk64(fs->io, old_blk,
1886 fs->inode_blocks_per_group,
1891 * The end of the inode table segment often contains
1892 * all zeros, and we're often only moving the inode
1893 * table down a block or two. If so, we can optimize
1894 * things by not rewriting blocks that we know to be zero
1897 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1900 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1901 #ifdef RESIZE2FS_DEBUG
1902 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1903 printf("%d blocks of zeros...\n", n);
1905 num = fs->inode_blocks_per_group;
1909 retval = io_channel_write_blk64(fs->io, new_blk,
1910 num, rfs->itable_buf);
1912 io_channel_write_blk64(fs->io, old_blk,
1913 num, rfs->itable_buf);
1917 retval = io_channel_write_blk64(fs->io,
1918 old_blk + fs->inode_blocks_per_group,
1919 diff, (rfs->itable_buf +
1920 (fs->inode_blocks_per_group - diff) *
1926 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1927 j < fs->inode_blocks_per_group;) {
1928 if (new_bmap == NULL ||
1929 !ext2fs_test_block_bitmap2(new_bmap, blk)) {
1930 ext2fs_block_alloc_stats2(fs, blk, -1);
1931 cluster_freed = EXT2FS_CLUSTER_RATIO(fs) -
1932 (blk & EXT2FS_CLUSTER_MASK(fs));
1933 blk += cluster_freed;
1941 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
1942 ext2fs_group_desc_csum_set(rfs->old_fs, i);
1943 ext2fs_mark_super_dirty(rfs->old_fs);
1944 ext2fs_flush(rfs->old_fs);
1946 if (rfs->progress) {
1947 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1953 mark_table_blocks(fs, fs->block_map);
1955 #ifdef RESIZE2FS_DEBUG
1956 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1957 printf("Inode table move finished.\n");
1963 ext2fs_free_block_bitmap(new_bmap);
1968 * This function is used when expanding a file system. It frees the
1969 * superblock and block group descriptor blocks from the block group
1970 * which is no longer the last block group.
1972 static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs)
1974 ext2_filsys fs = rfs->new_fs;
1975 ext2_filsys old_fs = rfs->old_fs;
1977 dgrp_t old_last_bg = rfs->old_fs->group_desc_count - 1;
1978 dgrp_t last_bg = fs->group_desc_count - 1;
1979 blk64_t sb, old_desc;
1982 if (!(fs->super->s_feature_compat & EXT4_FEATURE_COMPAT_SPARSE_SUPER2))
1985 if (last_bg <= old_last_bg)
1988 if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
1989 fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
1992 if (old_fs->super->s_backup_bgs[0] != old_last_bg &&
1993 old_fs->super->s_backup_bgs[1] != old_last_bg)
1996 if (fs->super->s_backup_bgs[0] == old_last_bg ||
1997 fs->super->s_backup_bgs[1] == old_last_bg)
2000 retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, old_last_bg,
2001 &sb, &old_desc, NULL, &num);
2006 ext2fs_unmark_block_bitmap2(fs->block_map, sb);
2008 ext2fs_unmark_block_bitmap_range2(fs->block_map, old_desc, num);
2013 * This function is used when shrinking a file system. We need to
2014 * utilize blocks from what will be the new last block group for the
2015 * backup superblock and block group descriptor blocks.
2016 * Unfortunately, those blocks may be used by other files or fs
2017 * metadata blocks. We need to mark them as being in use.
2019 static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
2020 ext2fs_block_bitmap meta_bmap)
2022 ext2_filsys fs = rfs->new_fs;
2023 ext2_filsys old_fs = rfs->old_fs;
2025 dgrp_t old_last_bg = rfs->old_fs->group_desc_count - 1;
2026 dgrp_t last_bg = fs->group_desc_count - 1;
2028 blk64_t blk, sb, old_desc;
2032 if (!(fs->super->s_feature_compat & EXT4_FEATURE_COMPAT_SPARSE_SUPER2))
2035 if (last_bg >= old_last_bg)
2038 if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
2039 fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
2042 if (fs->super->s_backup_bgs[0] != last_bg &&
2043 fs->super->s_backup_bgs[1] != last_bg)
2046 if (old_fs->super->s_backup_bgs[0] == last_bg ||
2047 old_fs->super->s_backup_bgs[1] == last_bg)
2050 retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, last_bg,
2051 &sb, &old_desc, NULL, &num);
2056 fputs(_("Should never happen! No sb in last super_sparse bg?\n"),
2060 if (old_desc && old_desc != sb+1) {
2061 fputs(_("Should never happen! Unexpected old_desc in "
2062 "super_sparse bg?\n"),
2066 num = (old_desc) ? num : 1;
2068 /* Reserve the backup blocks */
2069 ext2fs_mark_block_bitmap_range2(fs->block_map, sb, num);
2071 for (g = 0; g < fs->group_desc_count; g++) {
2074 mb = ext2fs_block_bitmap_loc(fs, g);
2075 if ((mb >= sb) && (mb < sb + num)) {
2076 ext2fs_block_bitmap_loc_set(fs, g, 0);
2079 mb = ext2fs_inode_bitmap_loc(fs, g);
2080 if ((mb >= sb) && (mb < sb + num)) {
2081 ext2fs_inode_bitmap_loc_set(fs, g, 0);
2084 mb = ext2fs_inode_table_loc(fs, g);
2085 if ((mb < sb + num) &&
2086 (sb < mb + fs->inode_blocks_per_group)) {
2087 ext2fs_inode_table_loc_set(fs, g, 0);
2091 retval = ext2fs_allocate_group_table(fs, g, 0);
2097 for (blk = sb, i = 0; i < num; blk++, i++) {
2098 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
2099 !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
2100 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
2101 rfs->needed_blocks++;
2103 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
2109 * Fix the resize inode
2111 static errcode_t fix_resize_inode(ext2_filsys fs)
2113 struct ext2_inode inode;
2115 char *block_buf = NULL;
2117 if (!(fs->super->s_feature_compat &
2118 EXT2_FEATURE_COMPAT_RESIZE_INODE))
2121 retval = ext2fs_get_mem(fs->blocksize, &block_buf);
2122 if (retval) goto errout;
2124 retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
2125 if (retval) goto errout;
2127 ext2fs_iblk_set(fs, &inode, 1);
2129 retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
2130 if (retval) goto errout;
2132 if (!inode.i_block[EXT2_DIND_BLOCK]) {
2134 * Avoid zeroing out block #0; that's rude. This
2135 * should never happen anyway since the filesystem
2136 * should be fsck'ed and we assume it is consistent.
2138 fprintf(stderr, "%s",
2139 _("Should never happen: resize inode corrupt!\n"));
2143 memset(block_buf, 0, fs->blocksize);
2145 retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
2147 if (retval) goto errout;
2149 retval = ext2fs_create_resize_inode(fs);
2155 ext2fs_free_mem(&block_buf);
2160 * Finally, recalculate the summary information
2162 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
2166 unsigned int group = 0;
2167 unsigned int count = 0;
2168 blk64_t total_blocks_free = 0;
2169 int total_inodes_free = 0;
2172 blk64_t super_blk, old_desc_blk, new_desc_blk;
2173 int old_desc_blocks;
2176 * First calculate the block statistics
2178 uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
2179 ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
2181 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
2182 old_desc_blocks = fs->super->s_first_meta_bg;
2184 old_desc_blocks = fs->desc_blocks +
2185 fs->super->s_reserved_gdt_blocks;
2186 for (blk = B2C(fs->super->s_first_data_block);
2187 blk < ext2fs_blocks_count(fs->super);
2188 blk += EXT2FS_CLUSTER_RATIO(fs)) {
2190 !(EQ_CLSTR(blk, super_blk) ||
2191 ((old_desc_blk && old_desc_blocks &&
2192 GE_CLSTR(blk, old_desc_blk) &&
2193 LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
2194 ((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
2195 EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
2196 EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
2197 ((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
2198 LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
2199 + fs->inode_blocks_per_group))))) ||
2200 (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
2202 total_blocks_free++;
2205 if ((count == fs->super->s_clusters_per_group) ||
2206 EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
2207 ext2fs_bg_free_blocks_count_set(fs, group, group_free);
2208 ext2fs_group_desc_csum_set(fs, group);
2210 if (group >= fs->group_desc_count)
2214 uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
2215 ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
2218 if (fs->super->s_feature_incompat &
2219 EXT2_FEATURE_INCOMPAT_META_BG)
2220 old_desc_blocks = fs->super->s_first_meta_bg;
2222 old_desc_blocks = fs->desc_blocks +
2223 fs->super->s_reserved_gdt_blocks;
2226 total_blocks_free = C2B(total_blocks_free);
2227 ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
2230 * Next, calculate the inode statistics
2236 /* Protect loop from wrap-around if s_inodes_count maxed */
2237 uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
2238 for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
2240 !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
2242 total_inodes_free++;
2245 if ((count == fs->super->s_inodes_per_group) ||
2246 (ino == fs->super->s_inodes_count)) {
2247 ext2fs_bg_free_inodes_count_set(fs, group, group_free);
2248 ext2fs_group_desc_csum_set(fs, group);
2250 if (group >= fs->group_desc_count)
2254 uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
2257 fs->super->s_free_inodes_count = total_inodes_free;
2258 ext2fs_mark_super_dirty(fs);
2263 * Journal may have been relocated; update the backup journal blocks
2264 * in the superblock.
2266 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
2269 struct ext2_inode inode;
2271 if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
2274 /* External journal? Nothing to do. */
2275 if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
2278 retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
2281 memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
2282 fs->super->s_jnl_blocks[15] = inode.i_size_high;
2283 fs->super->s_jnl_blocks[16] = inode.i_size;
2284 fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
2285 ext2fs_mark_super_dirty(fs);
2289 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
2290 int old_desc_blocks)
2292 blk64_t super_blk, old_desc_blk, new_desc_blk;
2295 /* inode table blocks plus allocation bitmaps */
2296 overhead = fs->inode_blocks_per_group + 2;
2298 ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
2299 &old_desc_blk, &new_desc_blk, 0);
2300 if ((grp == 0) || super_blk)
2303 overhead += old_desc_blocks;
2304 else if (new_desc_blk)
2311 * calcluate the minimum number of blocks the given fs can be resized to
2313 blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
2315 ext2_ino_t inode_count;
2316 dgrp_t groups, flex_groups;
2317 blk64_t blks_needed, data_blocks;
2318 blk64_t grp, data_needed, last_start;
2319 blk64_t overhead = 0;
2320 int old_desc_blocks;
2321 int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
2324 * first figure out how many group descriptors we need to
2325 * handle the number of inodes we have
2327 inode_count = fs->super->s_inodes_count -
2328 fs->super->s_free_inodes_count;
2329 blks_needed = ext2fs_div_ceil(inode_count,
2330 fs->super->s_inodes_per_group) *
2331 (blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super);
2332 groups = ext2fs_div64_ceil(blks_needed,
2333 EXT2_BLOCKS_PER_GROUP(fs->super));
2334 #ifdef RESIZE2FS_DEBUG
2335 if (flags & RESIZE_DEBUG_MIN_CALC)
2336 printf("fs has %d inodes, %d groups required.\n",
2337 inode_count, groups);
2341 * number of old-style block group descriptor blocks
2343 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
2344 old_desc_blocks = fs->super->s_first_meta_bg;
2346 old_desc_blocks = fs->desc_blocks +
2347 fs->super->s_reserved_gdt_blocks;
2349 /* calculate how many blocks are needed for data */
2350 data_needed = ext2fs_blocks_count(fs->super) -
2351 ext2fs_free_blocks_count(fs->super);
2353 for (grp = 0; grp < fs->group_desc_count; grp++)
2354 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
2355 #ifdef RESIZE2FS_DEBUG
2356 if (flags & RESIZE_DEBUG_MIN_CALC)
2357 printf("fs requires %llu data blocks.\n", data_needed);
2361 * For ext4 we need to allow for up to a flex_bg worth of
2362 * inode tables of slack space so the resize operation can be
2363 * guaranteed to finish.
2365 flex_groups = groups;
2366 if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
2367 dgrp_t remainder = groups & (flexbg_size - 1);
2369 flex_groups += flexbg_size - remainder;
2370 if (flex_groups > fs->group_desc_count)
2371 flex_groups = fs->group_desc_count;
2375 * figure out how many data blocks we have given the number of groups
2376 * we need for our inodes
2378 data_blocks = EXT2_GROUPS_TO_BLOCKS(fs->super, groups);
2380 for (grp = 0; grp < flex_groups; grp++) {
2381 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
2384 * we want to keep track of how much data we can store in
2385 * the groups leading up to the last group so we can determine
2386 * how big the last group needs to be
2388 if (grp < (groups - 1))
2389 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
2392 if (data_blocks > overhead)
2393 data_blocks -= overhead;
2397 #ifdef RESIZE2FS_DEBUG
2398 if (flags & RESIZE_DEBUG_MIN_CALC)
2399 printf("With %d group(s), we have %llu blocks available.\n",
2400 groups, data_blocks);
2404 * if we need more group descriptors in order to accomodate our data
2405 * then we need to add them here
2407 blks_needed = data_needed;
2408 while (blks_needed > data_blocks) {
2409 blk64_t remainder = blks_needed - data_blocks;
2412 /* figure out how many more groups we need for the data */
2413 extra_grps = ext2fs_div64_ceil(remainder,
2414 EXT2_BLOCKS_PER_GROUP(fs->super));
2416 data_blocks += EXT2_GROUPS_TO_BLOCKS(fs->super, extra_grps);
2418 /* ok we have to account for the last group */
2419 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2420 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
2423 groups += extra_grps;
2424 if (!(fs->super->s_feature_incompat &
2425 EXT4_FEATURE_INCOMPAT_FLEX_BG))
2426 flex_groups = groups;
2427 else if (groups > flex_groups) {
2428 dgrp_t r = groups & (flexbg_size - 1);
2430 flex_groups = groups + flexbg_size - r;
2431 if (flex_groups > fs->group_desc_count)
2432 flex_groups = fs->group_desc_count;
2435 for (; grp < flex_groups; grp++) {
2436 overhead = calc_group_overhead(fs, grp,
2440 * again, we need to see how much data we cram into
2441 * all of the groups leading up to the last group
2443 if (grp < groups - 1)
2444 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
2447 data_blocks -= overhead;
2450 #ifdef RESIZE2FS_DEBUG
2451 if (flags & RESIZE_DEBUG_MIN_CALC)
2452 printf("Added %d extra group(s), "
2453 "blks_needed %llu, data_blocks %llu, "
2454 "last_start %llu\n", extra_grps, blks_needed,
2455 data_blocks, last_start);
2459 /* now for the fun voodoo */
2461 if ((fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
2462 (grp & ~(flexbg_size - 1)) == 0)
2463 grp = grp & ~(flexbg_size - 1);
2465 for (; grp < flex_groups; grp++)
2466 overhead += calc_group_overhead(fs, grp, old_desc_blocks);
2468 #ifdef RESIZE2FS_DEBUG
2469 if (flags & RESIZE_DEBUG_MIN_CALC)
2470 printf("Last group's overhead is %llu\n", overhead);
2474 * if this is the case then the last group is going to have data in it
2475 * so we need to adjust the size of the last group accordingly
2477 if (last_start < blks_needed) {
2478 blk64_t remainder = blks_needed - last_start;
2480 #ifdef RESIZE2FS_DEBUG
2481 if (flags & RESIZE_DEBUG_MIN_CALC)
2482 printf("Need %llu data blocks in last group\n",
2486 * 50 is a magic number that mkfs/resize uses to see if its
2487 * even worth making/resizing the fs. basically you need to
2488 * have at least 50 blocks in addition to the blocks needed
2489 * for the metadata in the last group
2492 overhead += remainder;
2498 overhead += fs->super->s_first_data_block;
2499 #ifdef RESIZE2FS_DEBUG
2500 if (flags & RESIZE_DEBUG_MIN_CALC)
2501 printf("Final size of last group is %lld\n", overhead);
2504 /* Add extra slack for bigalloc file systems */
2505 if (EXT2FS_CLUSTER_RATIO(fs) > 1)
2506 overhead += EXT2FS_CLUSTER_RATIO(fs) * 2;
2509 * since our last group doesn't have to be BLOCKS_PER_GROUP
2510 * large, we only do groups-1, and then add the number of
2511 * blocks needed to handle the group descriptor metadata+data
2514 blks_needed = EXT2_GROUPS_TO_BLOCKS(fs->super, groups - 1);
2515 blks_needed += overhead;
2518 * Make sure blks_needed covers the end of the inode table in
2519 * the last block group.
2521 overhead = ext2fs_inode_table_loc(fs, groups-1) +
2522 fs->inode_blocks_per_group;
2523 if (blks_needed < overhead)
2524 blks_needed = overhead;
2526 #ifdef RESIZE2FS_DEBUG
2527 if (flags & RESIZE_DEBUG_MIN_CALC)
2528 printf("Estimated blocks needed: %llu\n", blks_needed);
2532 * If at this point we've already added up more "needed" than
2533 * the current size, just return current size as minimum.
2535 if (blks_needed >= ext2fs_blocks_count(fs->super))
2536 return ext2fs_blocks_count(fs->super);
2538 * We need to reserve a few extra blocks if extents are
2539 * enabled, in case we need to grow the extent tree. The more
2540 * we shrink the file system, the more space we need.
2542 * The absolute worst case is every single data block is in
2543 * the part of the file system that needs to be evacuated,
2544 * with each data block needs to be in its own extent, and
2545 * with each inode needing at least one extent block.
2547 if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS) {
2548 blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
2550 unsigned int exts_per_blk = (fs->blocksize /
2551 sizeof(struct ext3_extent)) - 1;
2552 blk64_t worst_case = ((data_needed + exts_per_blk - 1) /
2555 if (worst_case < inode_count)
2556 worst_case = inode_count;
2558 if (safe_margin > worst_case)
2559 safe_margin = worst_case;
2561 #ifdef RESIZE2FS_DEBUG
2562 if (flags & RESIZE_DEBUG_MIN_CALC)
2563 printf("Extents safety margin: %llu\n", safe_margin);
2565 blks_needed += safe_margin;