2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
6 * Copyright (c) 2012 Martin Sucha
7 * Copyright (c) 2012 Frantisek Princ
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
14 * - Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * - Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * - The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 /** @addtogroup lwext4
39 * @brief Physical block allocator.
42 #include "ext4_config.h"
43 #include "ext4_balloc.h"
44 #include "ext4_super.h"
45 #include "ext4_crc32c.h"
46 #include "ext4_block_group.h"
48 #include "ext4_bitmap.h"
49 #include "ext4_inode.h"
51 /**@brief Compute number of block group from block address.
52 * @param sb superblock pointer.
53 * @param baddr Absolute address of block.
54 * @return Block group index
56 uint32_t ext4_balloc_get_bgid_of_block(struct ext4_sblock *s,
59 if (ext4_get32(s, first_data_block) && baddr)
62 return baddr / ext4_get32(s, blocks_per_group);
65 /**@brief Compute the starting block address of a block group
66 * @param sb superblock pointer.
67 * @param bgid block group index
68 * @return Block address
70 uint64_t ext4_balloc_get_block_of_bgid(struct ext4_sblock *s,
74 if (ext4_get32(s, first_data_block))
77 baddr += bgid * ext4_get32(s, blocks_per_group);
81 #if CONFIG_META_CSUM_ENABLE
82 static uint32_t ext4_balloc_bitmap_csum(struct ext4_sblock *sb,
85 uint32_t checksum = 0;
86 if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM)) {
87 uint32_t blocks_per_group = ext4_get32(sb, blocks_per_group);
89 /* First calculate crc32 checksum against fs uuid */
90 checksum = ext4_crc32c(EXT4_CRC32_INIT, sb->uuid,
92 /* Then calculate crc32 checksum against block_group_desc */
93 checksum = ext4_crc32c(checksum, bitmap, blocks_per_group / 8);
98 #define ext4_balloc_bitmap_csum(...) 0
101 void ext4_balloc_set_bitmap_csum(struct ext4_sblock *sb,
102 struct ext4_bgroup *bg,
103 void *bitmap __unused)
105 int desc_size = ext4_sb_get_desc_size(sb);
106 uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
107 uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
108 hi_checksum = to_le16(checksum >> 16);
110 if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
113 /* See if we need to assign a 32bit checksum */
114 bg->block_bitmap_csum_lo = lo_checksum;
115 if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
116 bg->block_bitmap_csum_hi = hi_checksum;
120 #if CONFIG_META_CSUM_ENABLE
122 ext4_balloc_verify_bitmap_csum(struct ext4_sblock *sb,
123 struct ext4_bgroup *bg,
124 void *bitmap __unused)
126 int desc_size = ext4_sb_get_desc_size(sb);
127 uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
128 uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
129 hi_checksum = to_le16(checksum >> 16);
131 if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
134 if (bg->block_bitmap_csum_lo != lo_checksum)
137 if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
138 if (bg->block_bitmap_csum_hi != hi_checksum)
144 #define ext4_balloc_verify_bitmap_csum(...) true
147 int ext4_balloc_free_block(struct ext4_inode_ref *inode_ref, ext4_fsblk_t baddr)
149 struct ext4_fs *fs = inode_ref->fs;
150 struct ext4_sblock *sb = &fs->sb;
152 uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, baddr);
153 uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
155 /* Load block group reference */
156 struct ext4_block_group_ref bg_ref;
157 int rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
161 struct ext4_bgroup *bg = bg_ref.block_group;
163 /* Load block with bitmap */
164 ext4_fsblk_t bitmap_block_addr =
165 ext4_bg_get_block_bitmap(bg, sb);
167 struct ext4_block bitmap_block;
169 rc = ext4_block_get(fs->bdev, &bitmap_block, bitmap_block_addr);
171 ext4_fs_put_block_group_ref(&bg_ref);
175 if (!ext4_balloc_verify_bitmap_csum(sb, bg, bitmap_block.data)) {
176 ext4_dbg(DEBUG_BALLOC,
177 DBG_WARN "Bitmap checksum failed."
178 "Group: %" PRIu32"\n",
183 ext4_bmap_bit_clr(bitmap_block.data, index_in_group);
184 ext4_balloc_set_bitmap_csum(sb, bg, bitmap_block.data);
185 bitmap_block.dirty = true;
187 /* Release block with bitmap */
188 rc = ext4_block_set(fs->bdev, &bitmap_block);
190 /* Error in saving bitmap */
191 ext4_fs_put_block_group_ref(&bg_ref);
195 uint32_t block_size = ext4_sb_get_block_size(sb);
197 /* Update superblock free blocks count */
198 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
200 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
202 /* Update inode blocks count */
203 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
204 ino_blocks -= block_size / EXT4_INODE_BLOCK_SIZE;
205 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
206 inode_ref->dirty = true;
208 /* Update block group free blocks count */
209 uint32_t free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
211 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
215 /* Release block group reference */
216 return ext4_fs_put_block_group_ref(&bg_ref);
219 int ext4_balloc_free_blocks(struct ext4_inode_ref *inode_ref, ext4_fsblk_t first,
223 struct ext4_fs *fs = inode_ref->fs;
224 struct ext4_sblock *sb = &fs->sb;
226 /* Compute indexes */
227 uint32_t bg_first = ext4_balloc_get_bgid_of_block(sb, first);
229 /* Compute indexes */
230 uint32_t bg_last = ext4_balloc_get_bgid_of_block(sb, first + count - 1);
232 if (!ext4_sb_feature_incom(sb, EXT4_FINCOM_FLEX_BG)) {
233 /*It is not possible without flex_bg that blocks are continuous
234 * and and last block belongs to other bg.*/
235 if (bg_last != bg_first) {
236 ext4_dbg(DEBUG_BALLOC, DBG_WARN "FLEX_BG: disabled & "
237 "bg_last: %"PRIu32" bg_first: %"PRIu32"\n",
242 /* Load block group reference */
243 struct ext4_block_group_ref bg_ref;
244 while (bg_first <= bg_last) {
246 rc = ext4_fs_get_block_group_ref(fs, bg_first, &bg_ref);
250 struct ext4_bgroup *bg = bg_ref.block_group;
252 uint32_t idx_in_bg_first;
253 idx_in_bg_first = ext4_fs_addr_to_idx_bg(sb, first);
255 /* Load block with bitmap */
256 ext4_fsblk_t bitmap_blk = ext4_bg_get_block_bitmap(bg, sb);
258 struct ext4_block blk;
259 rc = ext4_block_get(fs->bdev, &blk, bitmap_blk);
261 ext4_fs_put_block_group_ref(&bg_ref);
265 if (!ext4_balloc_verify_bitmap_csum(sb, bg, blk.data)) {
266 ext4_dbg(DEBUG_BALLOC,
267 DBG_WARN "Bitmap checksum failed."
268 "Group: %" PRIu32"\n",
272 free_cnt = ext4_sb_get_block_size(sb) * 8 - idx_in_bg_first;
274 /*If last block, free only count blocks*/
275 free_cnt = count > free_cnt ? free_cnt : count;
278 ext4_bmap_bits_free(blk.data, idx_in_bg_first, free_cnt);
279 ext4_balloc_set_bitmap_csum(sb, bg, blk.data);
285 /* Release block with bitmap */
286 rc = ext4_block_set(fs->bdev, &blk);
288 ext4_fs_put_block_group_ref(&bg_ref);
292 uint32_t block_size = ext4_sb_get_block_size(sb);
294 /* Update superblock free blocks count */
295 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
296 sb_free_blocks += free_cnt;
297 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
299 /* Update inode blocks count */
301 ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
302 ino_blocks -= free_cnt * (block_size / EXT4_INODE_BLOCK_SIZE);
303 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
304 inode_ref->dirty = true;
306 /* Update block group free blocks count */
307 uint32_t free_blocks;
308 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
309 free_blocks += free_cnt;
310 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
313 /* Release block group reference */
314 rc = ext4_fs_put_block_group_ref(&bg_ref);
321 /*All blocks should be released*/
322 ext4_assert(count == 0);
326 int ext4_balloc_alloc_block(struct ext4_inode_ref *inode_ref,
328 ext4_fsblk_t *fblock)
330 ext4_fsblk_t alloc = 0;
331 ext4_fsblk_t bmp_blk_adr;
332 uint32_t rel_blk_idx = 0;
333 uint64_t free_blocks;
335 struct ext4_sblock *sb = &inode_ref->fs->sb;
337 /* Load block group number for goal and relative index */
338 uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, goal);
339 uint32_t idx_in_bg = ext4_fs_addr_to_idx_bg(sb, goal);
342 struct ext4_block_group_ref bg_ref;
344 /* Load block group reference */
345 r = ext4_fs_get_block_group_ref(inode_ref->fs, block_group, &bg_ref);
349 struct ext4_bgroup *bg = bg_ref.block_group;
351 free_blocks = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
352 if (free_blocks == 0) {
353 /* This group has no free blocks */
357 /* Compute indexes */
358 ext4_fsblk_t first_in_bg;
359 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bg_ref.index);
361 uint32_t first_in_bg_index;
362 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
364 if (idx_in_bg < first_in_bg_index)
365 idx_in_bg = first_in_bg_index;
367 /* Load block with bitmap */
368 bmp_blk_adr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
370 r = ext4_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
372 ext4_fs_put_block_group_ref(&bg_ref);
376 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
377 ext4_dbg(DEBUG_BALLOC,
378 DBG_WARN "Bitmap checksum failed."
379 "Group: %" PRIu32"\n",
383 /* Check if goal is free */
384 if (ext4_bmap_is_bit_clr(b.data, idx_in_bg)) {
385 ext4_bmap_bit_set(b.data, idx_in_bg);
386 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group,
389 r = ext4_block_set(inode_ref->fs->bdev, &b);
391 ext4_fs_put_block_group_ref(&bg_ref);
395 alloc = ext4_fs_bg_idx_to_addr(sb, idx_in_bg, block_group);
399 uint32_t blk_in_bg = ext4_blocks_in_group_cnt(sb, block_group);
401 uint32_t end_idx = (idx_in_bg + 63) & ~63;
402 if (end_idx > blk_in_bg)
405 /* Try to find free block near to goal */
407 for (tmp_idx = idx_in_bg + 1; tmp_idx < end_idx; ++tmp_idx) {
408 if (ext4_bmap_is_bit_clr(b.data, tmp_idx)) {
409 ext4_bmap_bit_set(b.data, tmp_idx);
411 ext4_balloc_set_bitmap_csum(sb, bg, b.data);
413 r = ext4_block_set(inode_ref->fs->bdev, &b);
417 alloc = ext4_fs_bg_idx_to_addr(sb, tmp_idx, block_group);
422 /* Find free bit in bitmap */
423 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg, &rel_blk_idx);
425 ext4_bmap_bit_set(b.data, rel_blk_idx);
426 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
428 r = ext4_block_set(inode_ref->fs->bdev, &b);
432 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, block_group);
436 /* No free block found yet */
437 r = ext4_block_set(inode_ref->fs->bdev, &b);
439 ext4_fs_put_block_group_ref(&bg_ref);
445 r = ext4_fs_put_block_group_ref(&bg_ref);
449 /* Try other block groups */
450 uint32_t block_group_count = ext4_block_group_cnt(sb);
451 uint32_t bgid = (block_group + 1) % block_group_count;
452 uint32_t count = block_group_count;
455 r = ext4_fs_get_block_group_ref(inode_ref->fs, bgid, &bg_ref);
459 struct ext4_bgroup *bg = bg_ref.block_group;
460 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
461 if (free_blocks == 0) {
462 /* This group has no free blocks */
466 /* Load block with bitmap */
467 bmp_blk_adr = ext4_bg_get_block_bitmap(bg, sb);
468 r = ext4_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
470 ext4_fs_put_block_group_ref(&bg_ref);
474 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
475 ext4_dbg(DEBUG_BALLOC,
476 DBG_WARN "Bitmap checksum failed."
477 "Group: %" PRIu32"\n",
481 /* Compute indexes */
482 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bgid);
483 idx_in_bg = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
484 blk_in_bg = ext4_blocks_in_group_cnt(sb, bgid);
485 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
487 if (idx_in_bg < first_in_bg_index)
488 idx_in_bg = first_in_bg_index;
490 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg,
493 ext4_bmap_bit_set(b.data, rel_blk_idx);
494 ext4_balloc_set_bitmap_csum(sb, bg, b.data);
496 r = ext4_block_set(inode_ref->fs->bdev, &b);
498 ext4_fs_put_block_group_ref(&bg_ref);
502 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bgid);
506 r = ext4_block_set(inode_ref->fs->bdev, &b);
508 ext4_fs_put_block_group_ref(&bg_ref);
513 r = ext4_fs_put_block_group_ref(&bg_ref);
518 /* Goto next group */
519 bgid = (bgid + 1) % block_group_count;
526 /* Empty command - because of syntax */
529 uint32_t block_size = ext4_sb_get_block_size(sb);
531 /* Update superblock free blocks count */
532 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
534 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
536 /* Update inode blocks (different block size!) count */
537 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
538 ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
539 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
540 inode_ref->dirty = true;
542 /* Update block group free blocks count */
544 uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
546 ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
549 r = ext4_fs_put_block_group_ref(&bg_ref);
555 int ext4_balloc_try_alloc_block(struct ext4_inode_ref *inode_ref,
556 ext4_fsblk_t baddr, bool *free)
560 struct ext4_fs *fs = inode_ref->fs;
561 struct ext4_sblock *sb = &fs->sb;
563 /* Compute indexes */
564 uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, baddr);
565 uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
567 /* Load block group reference */
568 struct ext4_block_group_ref bg_ref;
569 rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
573 /* Load block with bitmap */
574 ext4_fsblk_t bmp_blk_addr;
575 bmp_blk_addr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
578 rc = ext4_block_get(fs->bdev, &b, bmp_blk_addr);
580 ext4_fs_put_block_group_ref(&bg_ref);
584 if (!ext4_balloc_verify_bitmap_csum(sb, bg_ref.block_group, b.data)) {
585 ext4_dbg(DEBUG_BALLOC,
586 DBG_WARN "Bitmap checksum failed."
587 "Group: %" PRIu32"\n",
591 /* Check if block is free */
592 *free = ext4_bmap_is_bit_clr(b.data, index_in_group);
594 /* Allocate block if possible */
596 ext4_bmap_bit_set(b.data, index_in_group);
597 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
601 /* Release block with bitmap */
602 rc = ext4_block_set(fs->bdev, &b);
604 /* Error in saving bitmap */
605 ext4_fs_put_block_group_ref(&bg_ref);
609 /* If block is not free, return */
613 uint32_t block_size = ext4_sb_get_block_size(sb);
615 /* Update superblock free blocks count */
616 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
618 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
620 /* Update inode blocks count */
621 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
622 ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
623 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
624 inode_ref->dirty = true;
626 /* Update block group free blocks count */
627 uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
629 ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
634 return ext4_fs_put_block_group_ref(&bg_ref);