2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
5 * Copyright (c) 2012 Martin Sucha
6 * Copyright (c) 2012 Frantisek Princ
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * - Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * - Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * - The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 /** @addtogroup lwext4
38 * @brief Physical block allocator.
41 #include <ext4_config.h>
42 #include <ext4_types.h>
43 #include <ext4_misc.h>
44 #include <ext4_errno.h>
45 #include <ext4_debug.h>
47 #include <ext4_trans.h>
48 #include <ext4_balloc.h>
49 #include <ext4_super.h>
50 #include <ext4_crc32.h>
51 #include <ext4_block_group.h>
53 #include <ext4_bitmap.h>
54 #include <ext4_inode.h>
56 /**@brief Compute number of block group from block address.
57 * @param sb superblock pointer.
58 * @param baddr Absolute address of block.
59 * @return Block group index
61 uint32_t ext4_balloc_get_bgid_of_block(struct ext4_sblock *s,
64 if (ext4_get32(s, first_data_block) && baddr)
67 return (uint32_t)(baddr / ext4_get32(s, blocks_per_group));
70 /**@brief Compute the starting block address of a block group
71 * @param sb superblock pointer.
72 * @param bgid block group index
73 * @return Block address
75 uint64_t ext4_balloc_get_block_of_bgid(struct ext4_sblock *s,
79 if (ext4_get32(s, first_data_block))
82 baddr += bgid * ext4_get32(s, blocks_per_group);
86 #if CONFIG_META_CSUM_ENABLE
87 static uint32_t ext4_balloc_bitmap_csum(struct ext4_sblock *sb,
90 uint32_t checksum = 0;
91 if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM)) {
92 uint32_t blocks_per_group = ext4_get32(sb, blocks_per_group);
94 /* First calculate crc32 checksum against fs uuid */
95 checksum = ext4_crc32c(EXT4_CRC32_INIT, sb->uuid,
97 /* Then calculate crc32 checksum against block_group_desc */
98 checksum = ext4_crc32c(checksum, bitmap, blocks_per_group / 8);
103 #define ext4_balloc_bitmap_csum(...) 0
106 void ext4_balloc_set_bitmap_csum(struct ext4_sblock *sb,
107 struct ext4_bgroup *bg,
108 void *bitmap __unused)
110 int desc_size = ext4_sb_get_desc_size(sb);
111 uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
112 uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
113 hi_checksum = to_le16(checksum >> 16);
115 if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
118 /* See if we need to assign a 32bit checksum */
119 bg->block_bitmap_csum_lo = lo_checksum;
120 if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
121 bg->block_bitmap_csum_hi = hi_checksum;
125 #if CONFIG_META_CSUM_ENABLE
127 ext4_balloc_verify_bitmap_csum(struct ext4_sblock *sb,
128 struct ext4_bgroup *bg,
129 void *bitmap __unused)
131 int desc_size = ext4_sb_get_desc_size(sb);
132 uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
133 uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
134 hi_checksum = to_le16(checksum >> 16);
136 if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
139 if (bg->block_bitmap_csum_lo != lo_checksum)
142 if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
143 if (bg->block_bitmap_csum_hi != hi_checksum)
149 #define ext4_balloc_verify_bitmap_csum(...) true
152 int ext4_balloc_free_block(struct ext4_inode_ref *inode_ref, ext4_fsblk_t baddr)
154 struct ext4_fs *fs = inode_ref->fs;
155 struct ext4_sblock *sb = &fs->sb;
157 uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, baddr);
158 uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
160 /* Load block group reference */
161 struct ext4_block_group_ref bg_ref;
162 int rc = ext4_fs_get_block_group_ref(fs, bg_id, &bg_ref);
166 struct ext4_bgroup *bg = bg_ref.block_group;
168 /* Load block with bitmap */
169 ext4_fsblk_t bitmap_block_addr =
170 ext4_bg_get_block_bitmap(bg, sb);
172 struct ext4_block bitmap_block;
174 rc = ext4_trans_block_get(fs->bdev, &bitmap_block, bitmap_block_addr);
176 ext4_fs_put_block_group_ref(&bg_ref);
180 if (!ext4_balloc_verify_bitmap_csum(sb, bg, bitmap_block.data)) {
181 ext4_dbg(DEBUG_BALLOC,
182 DBG_WARN "Bitmap checksum failed."
183 "Group: %" PRIu32"\n",
188 ext4_bmap_bit_clr(bitmap_block.data, index_in_group);
189 ext4_balloc_set_bitmap_csum(sb, bg, bitmap_block.data);
190 ext4_trans_set_block_dirty(bitmap_block.buf);
192 /* Release block with bitmap */
193 rc = ext4_block_set(fs->bdev, &bitmap_block);
195 /* Error in saving bitmap */
196 ext4_fs_put_block_group_ref(&bg_ref);
200 uint32_t block_size = ext4_sb_get_block_size(sb);
202 /* Update superblock free blocks count */
203 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
205 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
207 /* Update inode blocks count */
208 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
209 ino_blocks -= block_size / EXT4_INODE_BLOCK_SIZE;
210 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
211 inode_ref->dirty = true;
213 /* Update block group free blocks count */
214 uint32_t free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
216 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
220 rc = ext4_trans_try_revoke_block(fs->bdev, baddr);
222 bg_ref.dirty = false;
223 ext4_fs_put_block_group_ref(&bg_ref);
226 ext4_bcache_invalidate_lba(fs->bdev->bc, baddr, 1);
227 /* Release block group reference */
228 rc = ext4_fs_put_block_group_ref(&bg_ref);
233 int ext4_balloc_free_blocks(struct ext4_inode_ref *inode_ref,
234 ext4_fsblk_t first, uint32_t count)
237 uint32_t blk_cnt = count;
238 ext4_fsblk_t start_block = first;
239 struct ext4_fs *fs = inode_ref->fs;
240 struct ext4_sblock *sb = &fs->sb;
242 /* Compute indexes */
243 uint32_t bg_first = ext4_balloc_get_bgid_of_block(sb, first);
245 /* Compute indexes */
246 uint32_t bg_last = ext4_balloc_get_bgid_of_block(sb, first + count - 1);
248 if (!ext4_sb_feature_incom(sb, EXT4_FINCOM_FLEX_BG)) {
249 /*It is not possible without flex_bg that blocks are continuous
250 * and and last block belongs to other bg.*/
251 if (bg_last != bg_first) {
252 ext4_dbg(DEBUG_BALLOC, DBG_WARN "FLEX_BG: disabled & "
253 "bg_last: %"PRIu32" bg_first: %"PRIu32"\n",
258 /* Load block group reference */
259 struct ext4_block_group_ref bg_ref;
260 while (bg_first <= bg_last) {
262 rc = ext4_fs_get_block_group_ref(fs, bg_first, &bg_ref);
266 struct ext4_bgroup *bg = bg_ref.block_group;
268 uint32_t idx_in_bg_first;
269 idx_in_bg_first = ext4_fs_addr_to_idx_bg(sb, first);
271 /* Load block with bitmap */
272 ext4_fsblk_t bitmap_blk = ext4_bg_get_block_bitmap(bg, sb);
274 struct ext4_block blk;
275 rc = ext4_trans_block_get(fs->bdev, &blk, bitmap_blk);
277 ext4_fs_put_block_group_ref(&bg_ref);
281 if (!ext4_balloc_verify_bitmap_csum(sb, bg, blk.data)) {
282 ext4_dbg(DEBUG_BALLOC,
283 DBG_WARN "Bitmap checksum failed."
284 "Group: %" PRIu32"\n",
288 free_cnt = ext4_sb_get_block_size(sb) * 8 - idx_in_bg_first;
290 /*If last block, free only count blocks*/
291 free_cnt = count > free_cnt ? free_cnt : count;
294 ext4_bmap_bits_free(blk.data, idx_in_bg_first, free_cnt);
295 ext4_balloc_set_bitmap_csum(sb, bg, blk.data);
296 ext4_trans_set_block_dirty(blk.buf);
301 /* Release block with bitmap */
302 rc = ext4_block_set(fs->bdev, &blk);
304 ext4_fs_put_block_group_ref(&bg_ref);
308 uint32_t block_size = ext4_sb_get_block_size(sb);
310 /* Update superblock free blocks count */
311 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
312 sb_free_blocks += free_cnt;
313 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
315 /* Update inode blocks count */
317 ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
318 ino_blocks -= free_cnt * (block_size / EXT4_INODE_BLOCK_SIZE);
319 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
320 inode_ref->dirty = true;
322 /* Update block group free blocks count */
323 uint32_t free_blocks;
324 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
325 free_blocks += free_cnt;
326 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
329 /* Release block group reference */
330 rc = ext4_fs_put_block_group_ref(&bg_ref);
338 for (i = 0;i < blk_cnt;i++) {
339 rc = ext4_trans_try_revoke_block(fs->bdev, start_block + i);
345 ext4_bcache_invalidate_lba(fs->bdev->bc, start_block, blk_cnt);
346 /*All blocks should be released*/
347 ext4_assert(count == 0);
352 int ext4_balloc_alloc_block(struct ext4_inode_ref *inode_ref,
354 ext4_fsblk_t *fblock)
356 ext4_fsblk_t alloc = 0;
357 ext4_fsblk_t bmp_blk_adr;
358 uint32_t rel_blk_idx = 0;
359 uint64_t free_blocks;
361 struct ext4_sblock *sb = &inode_ref->fs->sb;
363 /* Load block group number for goal and relative index */
364 uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, goal);
365 uint32_t idx_in_bg = ext4_fs_addr_to_idx_bg(sb, goal);
368 struct ext4_block_group_ref bg_ref;
370 /* Load block group reference */
371 r = ext4_fs_get_block_group_ref(inode_ref->fs, bg_id, &bg_ref);
375 struct ext4_bgroup *bg = bg_ref.block_group;
377 free_blocks = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
378 if (free_blocks == 0) {
379 /* This group has no free blocks */
383 /* Compute indexes */
384 ext4_fsblk_t first_in_bg;
385 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bg_ref.index);
387 uint32_t first_in_bg_index;
388 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
390 if (idx_in_bg < first_in_bg_index)
391 idx_in_bg = first_in_bg_index;
393 /* Load block with bitmap */
394 bmp_blk_adr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
396 r = ext4_trans_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
398 ext4_fs_put_block_group_ref(&bg_ref);
402 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
403 ext4_dbg(DEBUG_BALLOC,
404 DBG_WARN "Bitmap checksum failed."
405 "Group: %" PRIu32"\n",
409 /* Check if goal is free */
410 if (ext4_bmap_is_bit_clr(b.data, idx_in_bg)) {
411 ext4_bmap_bit_set(b.data, idx_in_bg);
412 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group,
414 ext4_trans_set_block_dirty(b.buf);
415 r = ext4_block_set(inode_ref->fs->bdev, &b);
417 ext4_fs_put_block_group_ref(&bg_ref);
421 alloc = ext4_fs_bg_idx_to_addr(sb, idx_in_bg, bg_id);
425 uint32_t blk_in_bg = ext4_blocks_in_group_cnt(sb, bg_id);
427 uint32_t end_idx = (idx_in_bg + 63) & ~63;
428 if (end_idx > blk_in_bg)
431 /* Try to find free block near to goal */
433 for (tmp_idx = idx_in_bg + 1; tmp_idx < end_idx; ++tmp_idx) {
434 if (ext4_bmap_is_bit_clr(b.data, tmp_idx)) {
435 ext4_bmap_bit_set(b.data, tmp_idx);
437 ext4_balloc_set_bitmap_csum(sb, bg, b.data);
438 ext4_trans_set_block_dirty(b.buf);
439 r = ext4_block_set(inode_ref->fs->bdev, &b);
443 alloc = ext4_fs_bg_idx_to_addr(sb, tmp_idx, bg_id);
448 /* Find free bit in bitmap */
449 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg, &rel_blk_idx);
451 ext4_bmap_bit_set(b.data, rel_blk_idx);
452 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
453 ext4_trans_set_block_dirty(b.buf);
454 r = ext4_block_set(inode_ref->fs->bdev, &b);
458 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bg_id);
462 /* No free block found yet */
463 r = ext4_block_set(inode_ref->fs->bdev, &b);
465 ext4_fs_put_block_group_ref(&bg_ref);
471 r = ext4_fs_put_block_group_ref(&bg_ref);
475 /* Try other block groups */
476 uint32_t block_group_count = ext4_block_group_cnt(sb);
477 uint32_t bgid = (bg_id + 1) % block_group_count;
478 uint32_t count = block_group_count;
481 r = ext4_fs_get_block_group_ref(inode_ref->fs, bgid, &bg_ref);
485 struct ext4_bgroup *bg = bg_ref.block_group;
486 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
487 if (free_blocks == 0) {
488 /* This group has no free blocks */
492 /* Load block with bitmap */
493 bmp_blk_adr = ext4_bg_get_block_bitmap(bg, sb);
494 r = ext4_trans_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
496 ext4_fs_put_block_group_ref(&bg_ref);
500 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
501 ext4_dbg(DEBUG_BALLOC,
502 DBG_WARN "Bitmap checksum failed."
503 "Group: %" PRIu32"\n",
507 /* Compute indexes */
508 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bgid);
509 idx_in_bg = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
510 blk_in_bg = ext4_blocks_in_group_cnt(sb, bgid);
511 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
513 if (idx_in_bg < first_in_bg_index)
514 idx_in_bg = first_in_bg_index;
516 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg,
519 ext4_bmap_bit_set(b.data, rel_blk_idx);
520 ext4_balloc_set_bitmap_csum(sb, bg, b.data);
521 ext4_trans_set_block_dirty(b.buf);
522 r = ext4_block_set(inode_ref->fs->bdev, &b);
524 ext4_fs_put_block_group_ref(&bg_ref);
528 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bgid);
532 r = ext4_block_set(inode_ref->fs->bdev, &b);
534 ext4_fs_put_block_group_ref(&bg_ref);
539 r = ext4_fs_put_block_group_ref(&bg_ref);
544 /* Goto next group */
545 bgid = (bgid + 1) % block_group_count;
552 /* Empty command - because of syntax */
555 uint32_t block_size = ext4_sb_get_block_size(sb);
557 /* Update superblock free blocks count */
558 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
560 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
562 /* Update inode blocks (different block size!) count */
563 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
564 ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
565 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
566 inode_ref->dirty = true;
568 /* Update block group free blocks count */
570 uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
572 ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
575 r = ext4_fs_put_block_group_ref(&bg_ref);
581 int ext4_balloc_try_alloc_block(struct ext4_inode_ref *inode_ref,
582 ext4_fsblk_t baddr, bool *free)
586 struct ext4_fs *fs = inode_ref->fs;
587 struct ext4_sblock *sb = &fs->sb;
589 /* Compute indexes */
590 uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, baddr);
591 uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
593 /* Load block group reference */
594 struct ext4_block_group_ref bg_ref;
595 rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
599 /* Load block with bitmap */
600 ext4_fsblk_t bmp_blk_addr;
601 bmp_blk_addr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
604 rc = ext4_trans_block_get(fs->bdev, &b, bmp_blk_addr);
606 ext4_fs_put_block_group_ref(&bg_ref);
610 if (!ext4_balloc_verify_bitmap_csum(sb, bg_ref.block_group, b.data)) {
611 ext4_dbg(DEBUG_BALLOC,
612 DBG_WARN "Bitmap checksum failed."
613 "Group: %" PRIu32"\n",
617 /* Check if block is free */
618 *free = ext4_bmap_is_bit_clr(b.data, index_in_group);
620 /* Allocate block if possible */
622 ext4_bmap_bit_set(b.data, index_in_group);
623 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
624 ext4_trans_set_block_dirty(b.buf);
627 /* Release block with bitmap */
628 rc = ext4_block_set(fs->bdev, &b);
630 /* Error in saving bitmap */
631 ext4_fs_put_block_group_ref(&bg_ref);
635 /* If block is not free, return */
639 uint32_t block_size = ext4_sb_get_block_size(sb);
641 /* Update superblock free blocks count */
642 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
644 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
646 /* Update inode blocks count */
647 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
648 ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
649 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
650 inode_ref->dirty = true;
652 /* Update block group free blocks count */
653 uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
655 ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
660 return ext4_fs_put_block_group_ref(&bg_ref);