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_balloc.h"
43 #include "ext4_super.h"
44 #include "ext4_crc32c.h"
45 #include "ext4_block_group.h"
47 #include "ext4_bitmap.h"
48 #include "ext4_inode.h"
50 /**@brief Compute number of block group from block address.
51 * @param sb superblock pointer.
52 * @param baddr Absolute address of block.
53 * @return Block group index
55 uint32_t ext4_balloc_get_bgid_of_block(struct ext4_sblock *s,
58 if (ext4_get32(s, first_data_block) && baddr)
61 return baddr / ext4_get32(s, blocks_per_group);
64 /**@brief Compute the starting block address of a block group
65 * @param sb superblock pointer.
66 * @param bgid block group index
67 * @return Block address
69 uint64_t ext4_balloc_get_block_of_bgid(struct ext4_sblock *s,
73 if (ext4_get32(s, first_data_block))
76 baddr += bgid * ext4_get32(s, blocks_per_group);
80 #if CONFIG_META_CSUM_ENABLE
81 static uint32_t ext4_balloc_bitmap_csum(struct ext4_sblock *sb,
84 uint32_t checksum = 0;
85 if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM)) {
86 uint32_t blocks_per_group = ext4_get32(sb, blocks_per_group);
88 /* First calculate crc32 checksum against fs uuid */
89 checksum = ext4_crc32c(EXT4_CRC32_INIT, sb->uuid,
91 /* Then calculate crc32 checksum against block_group_desc */
92 checksum = ext4_crc32c(checksum, bitmap, blocks_per_group / 8);
97 #define ext4_balloc_bitmap_csum(...) 0
100 void ext4_balloc_set_bitmap_csum(struct ext4_sblock *sb,
101 struct ext4_bgroup *bg,
102 void *bitmap __unused)
104 int desc_size = ext4_sb_get_desc_size(sb);
105 uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
106 uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
107 hi_checksum = to_le16(checksum >> 16);
109 if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
112 /* See if we need to assign a 32bit checksum */
113 bg->block_bitmap_csum_lo = lo_checksum;
114 if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
115 bg->block_bitmap_csum_hi = hi_checksum;
119 #if CONFIG_META_CSUM_ENABLE
121 ext4_balloc_verify_bitmap_csum(struct ext4_sblock *sb,
122 struct ext4_bgroup *bg,
123 void *bitmap __unused)
125 int desc_size = ext4_sb_get_desc_size(sb);
126 uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
127 uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
128 hi_checksum = to_le16(checksum >> 16);
130 if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
133 if (bg->block_bitmap_csum_lo != lo_checksum)
136 if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
137 if (bg->block_bitmap_csum_hi != hi_checksum)
143 #define ext4_balloc_verify_bitmap_csum(...) true
146 int ext4_balloc_free_block(struct ext4_inode_ref *inode_ref, ext4_fsblk_t baddr)
148 struct ext4_fs *fs = inode_ref->fs;
149 struct ext4_sblock *sb = &fs->sb;
151 uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, baddr);
152 uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
154 /* Load block group reference */
155 struct ext4_block_group_ref bg_ref;
156 int rc = ext4_fs_get_block_group_ref(fs, bg_id, &bg_ref);
160 struct ext4_bgroup *bg = bg_ref.block_group;
162 /* Load block with bitmap */
163 ext4_fsblk_t bitmap_block_addr =
164 ext4_bg_get_block_bitmap(bg, sb);
166 struct ext4_block bitmap_block;
168 rc = ext4_block_get(fs->bdev, &bitmap_block, bitmap_block_addr);
170 ext4_fs_put_block_group_ref(&bg_ref);
174 if (!ext4_balloc_verify_bitmap_csum(sb, bg, bitmap_block.data)) {
175 ext4_dbg(DEBUG_BALLOC,
176 DBG_WARN "Bitmap checksum failed."
177 "Group: %" PRIu32"\n",
182 ext4_bmap_bit_clr(bitmap_block.data, index_in_group);
183 ext4_balloc_set_bitmap_csum(sb, bg, bitmap_block.data);
184 ext4_bcache_set_dirty(bitmap_block.buf);
186 /* Release block with bitmap */
187 rc = ext4_block_set(fs->bdev, &bitmap_block);
189 /* Error in saving bitmap */
190 ext4_fs_put_block_group_ref(&bg_ref);
194 uint32_t block_size = ext4_sb_get_block_size(sb);
196 /* Update superblock free blocks count */
197 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
199 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
201 /* Update inode blocks count */
202 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
203 ino_blocks -= block_size / EXT4_INODE_BLOCK_SIZE;
204 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
205 inode_ref->dirty = true;
207 /* Update block group free blocks count */
208 uint32_t free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
210 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
214 /* Release block group reference */
215 return ext4_fs_put_block_group_ref(&bg_ref);
218 int ext4_balloc_free_blocks(struct ext4_inode_ref *inode_ref,
219 ext4_fsblk_t first, uint32_t count)
222 struct ext4_fs *fs = inode_ref->fs;
223 struct ext4_sblock *sb = &fs->sb;
225 /* Compute indexes */
226 uint32_t bg_first = ext4_balloc_get_bgid_of_block(sb, first);
228 /* Compute indexes */
229 uint32_t bg_last = ext4_balloc_get_bgid_of_block(sb, first + count - 1);
231 if (!ext4_sb_feature_incom(sb, EXT4_FINCOM_FLEX_BG)) {
232 /*It is not possible without flex_bg that blocks are continuous
233 * and and last block belongs to other bg.*/
234 if (bg_last != bg_first) {
235 ext4_dbg(DEBUG_BALLOC, DBG_WARN "FLEX_BG: disabled & "
236 "bg_last: %"PRIu32" bg_first: %"PRIu32"\n",
241 /* Load block group reference */
242 struct ext4_block_group_ref bg_ref;
243 while (bg_first <= bg_last) {
245 rc = ext4_fs_get_block_group_ref(fs, bg_first, &bg_ref);
249 struct ext4_bgroup *bg = bg_ref.block_group;
251 uint32_t idx_in_bg_first;
252 idx_in_bg_first = ext4_fs_addr_to_idx_bg(sb, first);
254 /* Load block with bitmap */
255 ext4_fsblk_t bitmap_blk = ext4_bg_get_block_bitmap(bg, sb);
257 struct ext4_block blk;
258 rc = ext4_block_get(fs->bdev, &blk, bitmap_blk);
260 ext4_fs_put_block_group_ref(&bg_ref);
264 if (!ext4_balloc_verify_bitmap_csum(sb, bg, blk.data)) {
265 ext4_dbg(DEBUG_BALLOC,
266 DBG_WARN "Bitmap checksum failed."
267 "Group: %" PRIu32"\n",
271 free_cnt = ext4_sb_get_block_size(sb) * 8 - idx_in_bg_first;
273 /*If last block, free only count blocks*/
274 free_cnt = count > free_cnt ? free_cnt : count;
277 ext4_bmap_bits_free(blk.data, idx_in_bg_first, free_cnt);
278 ext4_balloc_set_bitmap_csum(sb, bg, blk.data);
279 ext4_bcache_set_dirty(blk.buf);
284 /* Release block with bitmap */
285 rc = ext4_block_set(fs->bdev, &blk);
287 ext4_fs_put_block_group_ref(&bg_ref);
291 uint32_t block_size = ext4_sb_get_block_size(sb);
293 /* Update superblock free blocks count */
294 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
295 sb_free_blocks += free_cnt;
296 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
298 /* Update inode blocks count */
300 ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
301 ino_blocks -= free_cnt * (block_size / EXT4_INODE_BLOCK_SIZE);
302 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
303 inode_ref->dirty = true;
305 /* Update block group free blocks count */
306 uint32_t free_blocks;
307 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
308 free_blocks += free_cnt;
309 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
312 /* Release block group reference */
313 rc = ext4_fs_put_block_group_ref(&bg_ref);
320 /*All blocks should be released*/
321 ext4_assert(count == 0);
325 int ext4_balloc_alloc_block(struct ext4_inode_ref *inode_ref,
327 ext4_fsblk_t *fblock)
329 ext4_fsblk_t alloc = 0;
330 ext4_fsblk_t bmp_blk_adr;
331 uint32_t rel_blk_idx = 0;
332 uint64_t free_blocks;
334 struct ext4_sblock *sb = &inode_ref->fs->sb;
336 /* Load block group number for goal and relative index */
337 uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, goal);
338 uint32_t idx_in_bg = ext4_fs_addr_to_idx_bg(sb, goal);
341 struct ext4_block_group_ref bg_ref;
343 /* Load block group reference */
344 r = ext4_fs_get_block_group_ref(inode_ref->fs, bg_id, &bg_ref);
348 struct ext4_bgroup *bg = bg_ref.block_group;
350 free_blocks = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
351 if (free_blocks == 0) {
352 /* This group has no free blocks */
356 /* Compute indexes */
357 ext4_fsblk_t first_in_bg;
358 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bg_ref.index);
360 uint32_t first_in_bg_index;
361 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
363 if (idx_in_bg < first_in_bg_index)
364 idx_in_bg = first_in_bg_index;
366 /* Load block with bitmap */
367 bmp_blk_adr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
369 r = ext4_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
371 ext4_fs_put_block_group_ref(&bg_ref);
375 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
376 ext4_dbg(DEBUG_BALLOC,
377 DBG_WARN "Bitmap checksum failed."
378 "Group: %" PRIu32"\n",
382 /* Check if goal is free */
383 if (ext4_bmap_is_bit_clr(b.data, idx_in_bg)) {
384 ext4_bmap_bit_set(b.data, idx_in_bg);
385 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group,
387 ext4_bcache_set_dirty(b.buf);
388 r = ext4_block_set(inode_ref->fs->bdev, &b);
390 ext4_fs_put_block_group_ref(&bg_ref);
394 alloc = ext4_fs_bg_idx_to_addr(sb, idx_in_bg, bg_id);
398 uint32_t blk_in_bg = ext4_blocks_in_group_cnt(sb, bg_id);
400 uint32_t end_idx = (idx_in_bg + 63) & ~63;
401 if (end_idx > blk_in_bg)
404 /* Try to find free block near to goal */
406 for (tmp_idx = idx_in_bg + 1; tmp_idx < end_idx; ++tmp_idx) {
407 if (ext4_bmap_is_bit_clr(b.data, tmp_idx)) {
408 ext4_bmap_bit_set(b.data, tmp_idx);
410 ext4_balloc_set_bitmap_csum(sb, bg, b.data);
411 ext4_bcache_set_dirty(b.buf);
412 r = ext4_block_set(inode_ref->fs->bdev, &b);
416 alloc = ext4_fs_bg_idx_to_addr(sb, tmp_idx, bg_id);
421 /* Find free bit in bitmap */
422 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg, &rel_blk_idx);
424 ext4_bmap_bit_set(b.data, rel_blk_idx);
425 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
426 ext4_bcache_set_dirty(b.buf);
427 r = ext4_block_set(inode_ref->fs->bdev, &b);
431 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bg_id);
435 /* No free block found yet */
436 r = ext4_block_set(inode_ref->fs->bdev, &b);
438 ext4_fs_put_block_group_ref(&bg_ref);
444 r = ext4_fs_put_block_group_ref(&bg_ref);
448 /* Try other block groups */
449 uint32_t block_group_count = ext4_block_group_cnt(sb);
450 uint32_t bgid = (bg_id + 1) % block_group_count;
451 uint32_t count = block_group_count;
454 r = ext4_fs_get_block_group_ref(inode_ref->fs, bgid, &bg_ref);
458 struct ext4_bgroup *bg = bg_ref.block_group;
459 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
460 if (free_blocks == 0) {
461 /* This group has no free blocks */
465 /* Load block with bitmap */
466 bmp_blk_adr = ext4_bg_get_block_bitmap(bg, sb);
467 r = ext4_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
469 ext4_fs_put_block_group_ref(&bg_ref);
473 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
474 ext4_dbg(DEBUG_BALLOC,
475 DBG_WARN "Bitmap checksum failed."
476 "Group: %" PRIu32"\n",
480 /* Compute indexes */
481 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bgid);
482 idx_in_bg = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
483 blk_in_bg = ext4_blocks_in_group_cnt(sb, bgid);
484 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
486 if (idx_in_bg < first_in_bg_index)
487 idx_in_bg = first_in_bg_index;
489 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg,
492 ext4_bmap_bit_set(b.data, rel_blk_idx);
493 ext4_balloc_set_bitmap_csum(sb, bg, b.data);
494 ext4_bcache_set_dirty(b.buf);
495 r = ext4_block_set(inode_ref->fs->bdev, &b);
497 ext4_fs_put_block_group_ref(&bg_ref);
501 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bgid);
505 r = ext4_block_set(inode_ref->fs->bdev, &b);
507 ext4_fs_put_block_group_ref(&bg_ref);
512 r = ext4_fs_put_block_group_ref(&bg_ref);
517 /* Goto next group */
518 bgid = (bgid + 1) % block_group_count;
525 /* Empty command - because of syntax */
528 uint32_t block_size = ext4_sb_get_block_size(sb);
530 /* Update superblock free blocks count */
531 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
533 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
535 /* Update inode blocks (different block size!) count */
536 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
537 ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
538 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
539 inode_ref->dirty = true;
541 /* Update block group free blocks count */
543 uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
545 ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
548 r = ext4_fs_put_block_group_ref(&bg_ref);
554 int ext4_balloc_try_alloc_block(struct ext4_inode_ref *inode_ref,
555 ext4_fsblk_t baddr, bool *free)
559 struct ext4_fs *fs = inode_ref->fs;
560 struct ext4_sblock *sb = &fs->sb;
562 /* Compute indexes */
563 uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, baddr);
564 uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
566 /* Load block group reference */
567 struct ext4_block_group_ref bg_ref;
568 rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
572 /* Load block with bitmap */
573 ext4_fsblk_t bmp_blk_addr;
574 bmp_blk_addr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
577 rc = ext4_block_get(fs->bdev, &b, bmp_blk_addr);
579 ext4_fs_put_block_group_ref(&bg_ref);
583 if (!ext4_balloc_verify_bitmap_csum(sb, bg_ref.block_group, b.data)) {
584 ext4_dbg(DEBUG_BALLOC,
585 DBG_WARN "Bitmap checksum failed."
586 "Group: %" PRIu32"\n",
590 /* Check if block is free */
591 *free = ext4_bmap_is_bit_clr(b.data, index_in_group);
593 /* Allocate block if possible */
595 ext4_bmap_bit_set(b.data, index_in_group);
596 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
597 ext4_bcache_set_dirty(b.buf);
600 /* Release block with bitmap */
601 rc = ext4_block_set(fs->bdev, &b);
603 /* Error in saving bitmap */
604 ext4_fs_put_block_group_ref(&bg_ref);
608 /* If block is not free, return */
612 uint32_t block_size = ext4_sb_get_block_size(sb);
614 /* Update superblock free blocks count */
615 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
617 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
619 /* Update inode blocks count */
620 uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
621 ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
622 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
623 inode_ref->dirty = true;
625 /* Update block group free blocks count */
626 uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
628 ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
633 return ext4_fs_put_block_group_ref(&bg_ref);