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Commit | Line | Data |
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ac27a0ec | 1 | /* |
617ba13b | 2 | * linux/fs/ext4/balloc.c |
ac27a0ec DK |
3 | * |
4 | * Copyright (C) 1992, 1993, 1994, 1995 | |
5 | * Remy Card (card@masi.ibp.fr) | |
6 | * Laboratoire MASI - Institut Blaise Pascal | |
7 | * Universite Pierre et Marie Curie (Paris VI) | |
8 | * | |
9 | * Enhanced block allocation by Stephen Tweedie (sct@redhat.com), 1993 | |
10 | * Big-endian to little-endian byte-swapping/bitmaps by | |
11 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
12 | */ | |
13 | ||
14 | #include <linux/time.h> | |
15 | #include <linux/capability.h> | |
16 | #include <linux/fs.h> | |
dab291af | 17 | #include <linux/jbd2.h> |
ac27a0ec DK |
18 | #include <linux/quotaops.h> |
19 | #include <linux/buffer_head.h> | |
3dcf5451 CH |
20 | #include "ext4.h" |
21 | #include "ext4_jbd2.h" | |
717d50e4 | 22 | #include "group.h" |
e21675d4 | 23 | #include "mballoc.h" |
3dcf5451 | 24 | |
ac27a0ec DK |
25 | /* |
26 | * balloc.c contains the blocks allocation and deallocation routines | |
27 | */ | |
28 | ||
72b64b59 AM |
29 | /* |
30 | * Calculate the block group number and offset, given a block number | |
31 | */ | |
32 | void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr, | |
fd2d4291 | 33 | ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp) |
72b64b59 | 34 | { |
8c55e204 | 35 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
72b64b59 AM |
36 | ext4_grpblk_t offset; |
37 | ||
8c55e204 | 38 | blocknr = blocknr - le32_to_cpu(es->s_first_data_block); |
f4e5bc24 | 39 | offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)); |
72b64b59 AM |
40 | if (offsetp) |
41 | *offsetp = offset; | |
42 | if (blockgrpp) | |
8c55e204 | 43 | *blockgrpp = blocknr; |
72b64b59 AM |
44 | |
45 | } | |
46 | ||
0bf7e837 JS |
47 | static int ext4_block_in_group(struct super_block *sb, ext4_fsblk_t block, |
48 | ext4_group_t block_group) | |
49 | { | |
50 | ext4_group_t actual_group; | |
7477827f | 51 | ext4_get_group_no_and_offset(sb, block, &actual_group, NULL); |
0bf7e837 JS |
52 | if (actual_group == block_group) |
53 | return 1; | |
54 | return 0; | |
55 | } | |
56 | ||
57 | static int ext4_group_used_meta_blocks(struct super_block *sb, | |
58 | ext4_group_t block_group) | |
59 | { | |
60 | ext4_fsblk_t tmp; | |
61 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
62 | /* block bitmap, inode bitmap, and inode table blocks */ | |
63 | int used_blocks = sbi->s_itb_per_group + 2; | |
64 | ||
65 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { | |
66 | struct ext4_group_desc *gdp; | |
67 | struct buffer_head *bh; | |
68 | ||
69 | gdp = ext4_get_group_desc(sb, block_group, &bh); | |
70 | if (!ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), | |
71 | block_group)) | |
72 | used_blocks--; | |
73 | ||
74 | if (!ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), | |
75 | block_group)) | |
76 | used_blocks--; | |
77 | ||
78 | tmp = ext4_inode_table(sb, gdp); | |
79 | for (; tmp < ext4_inode_table(sb, gdp) + | |
80 | sbi->s_itb_per_group; tmp++) { | |
81 | if (!ext4_block_in_group(sb, tmp, block_group)) | |
82 | used_blocks -= 1; | |
83 | } | |
84 | } | |
85 | return used_blocks; | |
86 | } | |
c2ea3fde | 87 | |
717d50e4 AD |
88 | /* Initializes an uninitialized block bitmap if given, and returns the |
89 | * number of blocks free in the group. */ | |
90 | unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, | |
fd2d4291 | 91 | ext4_group_t block_group, struct ext4_group_desc *gdp) |
717d50e4 | 92 | { |
717d50e4 AD |
93 | int bit, bit_max; |
94 | unsigned free_blocks, group_blocks; | |
95 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
96 | ||
97 | if (bh) { | |
98 | J_ASSERT_BH(bh, buffer_locked(bh)); | |
99 | ||
100 | /* If checksum is bad mark all blocks used to prevent allocation | |
101 | * essentially implementing a per-group read-only flag. */ | |
102 | if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { | |
46e665e9 | 103 | ext4_error(sb, __func__, |
a9df9a49 | 104 | "Checksum bad for group %u", block_group); |
560671a0 AK |
105 | ext4_free_blks_set(sb, gdp, 0); |
106 | ext4_free_inodes_set(sb, gdp, 0); | |
107 | ext4_itable_unused_set(sb, gdp, 0); | |
717d50e4 AD |
108 | memset(bh->b_data, 0xff, sb->s_blocksize); |
109 | return 0; | |
110 | } | |
111 | memset(bh->b_data, 0, sb->s_blocksize); | |
112 | } | |
113 | ||
114 | /* Check for superblock and gdt backups in this group */ | |
115 | bit_max = ext4_bg_has_super(sb, block_group); | |
116 | ||
117 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) || | |
118 | block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) * | |
119 | sbi->s_desc_per_block) { | |
120 | if (bit_max) { | |
121 | bit_max += ext4_bg_num_gdb(sb, block_group); | |
122 | bit_max += | |
123 | le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks); | |
124 | } | |
125 | } else { /* For META_BG_BLOCK_GROUPS */ | |
6afd6707 | 126 | bit_max += ext4_bg_num_gdb(sb, block_group); |
717d50e4 AD |
127 | } |
128 | ||
129 | if (block_group == sbi->s_groups_count - 1) { | |
130 | /* | |
131 | * Even though mke2fs always initialize first and last group | |
132 | * if some other tool enabled the EXT4_BG_BLOCK_UNINIT we need | |
133 | * to make sure we calculate the right free blocks | |
134 | */ | |
135 | group_blocks = ext4_blocks_count(sbi->s_es) - | |
136 | le32_to_cpu(sbi->s_es->s_first_data_block) - | |
af5bc92d | 137 | (EXT4_BLOCKS_PER_GROUP(sb) * (sbi->s_groups_count - 1)); |
717d50e4 AD |
138 | } else { |
139 | group_blocks = EXT4_BLOCKS_PER_GROUP(sb); | |
140 | } | |
141 | ||
142 | free_blocks = group_blocks - bit_max; | |
143 | ||
144 | if (bh) { | |
0bf7e837 JS |
145 | ext4_fsblk_t start, tmp; |
146 | int flex_bg = 0; | |
d00a6d7b | 147 | |
717d50e4 AD |
148 | for (bit = 0; bit < bit_max; bit++) |
149 | ext4_set_bit(bit, bh->b_data); | |
150 | ||
d00a6d7b | 151 | start = ext4_group_first_block_no(sb, block_group); |
717d50e4 | 152 | |
0bf7e837 JS |
153 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, |
154 | EXT4_FEATURE_INCOMPAT_FLEX_BG)) | |
155 | flex_bg = 1; | |
717d50e4 | 156 | |
0bf7e837 JS |
157 | /* Set bits for block and inode bitmaps, and inode table */ |
158 | tmp = ext4_block_bitmap(sb, gdp); | |
159 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) | |
160 | ext4_set_bit(tmp - start, bh->b_data); | |
161 | ||
162 | tmp = ext4_inode_bitmap(sb, gdp); | |
163 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) | |
164 | ext4_set_bit(tmp - start, bh->b_data); | |
165 | ||
166 | tmp = ext4_inode_table(sb, gdp); | |
167 | for (; tmp < ext4_inode_table(sb, gdp) + | |
168 | sbi->s_itb_per_group; tmp++) { | |
169 | if (!flex_bg || | |
170 | ext4_block_in_group(sb, tmp, block_group)) | |
171 | ext4_set_bit(tmp - start, bh->b_data); | |
172 | } | |
717d50e4 AD |
173 | /* |
174 | * Also if the number of blocks within the group is | |
175 | * less than the blocksize * 8 ( which is the size | |
176 | * of bitmap ), set rest of the block bitmap to 1 | |
177 | */ | |
178 | mark_bitmap_end(group_blocks, sb->s_blocksize * 8, bh->b_data); | |
179 | } | |
0bf7e837 | 180 | return free_blocks - ext4_group_used_meta_blocks(sb, block_group); |
717d50e4 AD |
181 | } |
182 | ||
183 | ||
ac27a0ec DK |
184 | /* |
185 | * The free blocks are managed by bitmaps. A file system contains several | |
186 | * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap | |
187 | * block for inodes, N blocks for the inode table and data blocks. | |
188 | * | |
189 | * The file system contains group descriptors which are located after the | |
190 | * super block. Each descriptor contains the number of the bitmap block and | |
191 | * the free blocks count in the block. The descriptors are loaded in memory | |
e627432c | 192 | * when a file system is mounted (see ext4_fill_super). |
ac27a0ec DK |
193 | */ |
194 | ||
195 | ||
196 | #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1) | |
197 | ||
198 | /** | |
617ba13b | 199 | * ext4_get_group_desc() -- load group descriptor from disk |
ac27a0ec DK |
200 | * @sb: super block |
201 | * @block_group: given block group | |
202 | * @bh: pointer to the buffer head to store the block | |
203 | * group descriptor | |
204 | */ | |
af5bc92d | 205 | struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, |
fd2d4291 | 206 | ext4_group_t block_group, |
af5bc92d | 207 | struct buffer_head **bh) |
ac27a0ec | 208 | { |
498e5f24 TT |
209 | unsigned int group_desc; |
210 | unsigned int offset; | |
af5bc92d | 211 | struct ext4_group_desc *desc; |
617ba13b | 212 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
ac27a0ec DK |
213 | |
214 | if (block_group >= sbi->s_groups_count) { | |
af5bc92d TT |
215 | ext4_error(sb, "ext4_get_group_desc", |
216 | "block_group >= groups_count - " | |
a9df9a49 | 217 | "block_group = %u, groups_count = %u", |
af5bc92d | 218 | block_group, sbi->s_groups_count); |
ac27a0ec DK |
219 | |
220 | return NULL; | |
221 | } | |
222 | smp_rmb(); | |
223 | ||
617ba13b MC |
224 | group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); |
225 | offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); | |
ac27a0ec | 226 | if (!sbi->s_group_desc[group_desc]) { |
af5bc92d TT |
227 | ext4_error(sb, "ext4_get_group_desc", |
228 | "Group descriptor not loaded - " | |
498e5f24 | 229 | "block_group = %u, group_desc = %u, desc = %u", |
af5bc92d | 230 | block_group, group_desc, offset); |
ac27a0ec DK |
231 | return NULL; |
232 | } | |
233 | ||
0d1ee42f AR |
234 | desc = (struct ext4_group_desc *)( |
235 | (__u8 *)sbi->s_group_desc[group_desc]->b_data + | |
236 | offset * EXT4_DESC_SIZE(sb)); | |
ac27a0ec DK |
237 | if (bh) |
238 | *bh = sbi->s_group_desc[group_desc]; | |
0d1ee42f | 239 | return desc; |
ac27a0ec DK |
240 | } |
241 | ||
abcb2947 AK |
242 | static int ext4_valid_block_bitmap(struct super_block *sb, |
243 | struct ext4_group_desc *desc, | |
244 | unsigned int block_group, | |
245 | struct buffer_head *bh) | |
246 | { | |
247 | ext4_grpblk_t offset; | |
248 | ext4_grpblk_t next_zero_bit; | |
249 | ext4_fsblk_t bitmap_blk; | |
250 | ext4_fsblk_t group_first_block; | |
251 | ||
252 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { | |
253 | /* with FLEX_BG, the inode/block bitmaps and itable | |
254 | * blocks may not be in the group at all | |
255 | * so the bitmap validation will be skipped for those groups | |
256 | * or it has to also read the block group where the bitmaps | |
257 | * are located to verify they are set. | |
258 | */ | |
259 | return 1; | |
260 | } | |
261 | group_first_block = ext4_group_first_block_no(sb, block_group); | |
262 | ||
263 | /* check whether block bitmap block number is set */ | |
264 | bitmap_blk = ext4_block_bitmap(sb, desc); | |
265 | offset = bitmap_blk - group_first_block; | |
266 | if (!ext4_test_bit(offset, bh->b_data)) | |
267 | /* bad block bitmap */ | |
268 | goto err_out; | |
269 | ||
270 | /* check whether the inode bitmap block number is set */ | |
271 | bitmap_blk = ext4_inode_bitmap(sb, desc); | |
272 | offset = bitmap_blk - group_first_block; | |
273 | if (!ext4_test_bit(offset, bh->b_data)) | |
274 | /* bad block bitmap */ | |
275 | goto err_out; | |
276 | ||
277 | /* check whether the inode table block number is set */ | |
278 | bitmap_blk = ext4_inode_table(sb, desc); | |
279 | offset = bitmap_blk - group_first_block; | |
280 | next_zero_bit = ext4_find_next_zero_bit(bh->b_data, | |
281 | offset + EXT4_SB(sb)->s_itb_per_group, | |
282 | offset); | |
283 | if (next_zero_bit >= offset + EXT4_SB(sb)->s_itb_per_group) | |
284 | /* good bitmap for inode tables */ | |
285 | return 1; | |
286 | ||
287 | err_out: | |
46e665e9 | 288 | ext4_error(sb, __func__, |
abcb2947 AK |
289 | "Invalid block bitmap - " |
290 | "block_group = %d, block = %llu", | |
291 | block_group, bitmap_blk); | |
292 | return 0; | |
293 | } | |
ac27a0ec | 294 | /** |
574ca174 | 295 | * ext4_read_block_bitmap() |
ac27a0ec DK |
296 | * @sb: super block |
297 | * @block_group: given block group | |
298 | * | |
abcb2947 AK |
299 | * Read the bitmap for a given block_group,and validate the |
300 | * bits for block/inode/inode tables are set in the bitmaps | |
ac27a0ec DK |
301 | * |
302 | * Return buffer_head on success or NULL in case of failure. | |
303 | */ | |
717d50e4 | 304 | struct buffer_head * |
574ca174 | 305 | ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group) |
ac27a0ec | 306 | { |
af5bc92d TT |
307 | struct ext4_group_desc *desc; |
308 | struct buffer_head *bh = NULL; | |
7c9e69fa | 309 | ext4_fsblk_t bitmap_blk; |
ac27a0ec | 310 | |
717d50e4 | 311 | desc = ext4_get_group_desc(sb, block_group, NULL); |
ac27a0ec | 312 | if (!desc) |
7c9e69fa AK |
313 | return NULL; |
314 | bitmap_blk = ext4_block_bitmap(sb, desc); | |
abcb2947 AK |
315 | bh = sb_getblk(sb, bitmap_blk); |
316 | if (unlikely(!bh)) { | |
46e665e9 | 317 | ext4_error(sb, __func__, |
abcb2947 | 318 | "Cannot read block bitmap - " |
a9df9a49 | 319 | "block_group = %u, block_bitmap = %llu", |
e29d1cde | 320 | block_group, bitmap_blk); |
abcb2947 AK |
321 | return NULL; |
322 | } | |
c806e68f FB |
323 | if (buffer_uptodate(bh) && |
324 | !(desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) | |
abcb2947 AK |
325 | return bh; |
326 | ||
c806e68f | 327 | lock_buffer(bh); |
b5f10eed | 328 | spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group)); |
717d50e4 | 329 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { |
abcb2947 AK |
330 | ext4_init_block_bitmap(sb, bh, block_group, desc); |
331 | set_buffer_uptodate(bh); | |
b5f10eed | 332 | spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); |
3300beda | 333 | unlock_buffer(bh); |
abcb2947 | 334 | return bh; |
717d50e4 | 335 | } |
b5f10eed | 336 | spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); |
abcb2947 AK |
337 | if (bh_submit_read(bh) < 0) { |
338 | put_bh(bh); | |
46e665e9 | 339 | ext4_error(sb, __func__, |
ac27a0ec | 340 | "Cannot read block bitmap - " |
a9df9a49 | 341 | "block_group = %u, block_bitmap = %llu", |
e29d1cde | 342 | block_group, bitmap_blk); |
abcb2947 AK |
343 | return NULL; |
344 | } | |
519deca0 AK |
345 | ext4_valid_block_bitmap(sb, desc, block_group, bh); |
346 | /* | |
347 | * file system mounted not to panic on error, | |
348 | * continue with corrupt bitmap | |
349 | */ | |
ac27a0ec DK |
350 | return bh; |
351 | } | |
ac27a0ec DK |
352 | |
353 | /** | |
e21675d4 | 354 | * ext4_add_groupblocks() -- Add given blocks to an existing group |
ac27a0ec DK |
355 | * @handle: handle to this transaction |
356 | * @sb: super block | |
e21675d4 | 357 | * @block: start physcial block to add to the block group |
ac27a0ec | 358 | * @count: number of blocks to free |
c2ea3fde | 359 | * |
e21675d4 AK |
360 | * This marks the blocks as free in the bitmap. We ask the |
361 | * mballoc to reload the buddy after this by setting group | |
362 | * EXT4_GROUP_INFO_NEED_INIT_BIT flag | |
ac27a0ec | 363 | */ |
e21675d4 AK |
364 | void ext4_add_groupblocks(handle_t *handle, struct super_block *sb, |
365 | ext4_fsblk_t block, unsigned long count) | |
ac27a0ec DK |
366 | { |
367 | struct buffer_head *bitmap_bh = NULL; | |
368 | struct buffer_head *gd_bh; | |
fd2d4291 | 369 | ext4_group_t block_group; |
617ba13b | 370 | ext4_grpblk_t bit; |
498e5f24 | 371 | unsigned int i; |
af5bc92d TT |
372 | struct ext4_group_desc *desc; |
373 | struct ext4_super_block *es; | |
617ba13b | 374 | struct ext4_sb_info *sbi; |
560671a0 | 375 | int err = 0, ret, blk_free_count; |
e21675d4 AK |
376 | ext4_grpblk_t blocks_freed; |
377 | struct ext4_group_info *grp; | |
ac27a0ec | 378 | |
617ba13b | 379 | sbi = EXT4_SB(sb); |
ac27a0ec | 380 | es = sbi->s_es; |
e21675d4 | 381 | ext4_debug("Adding block(s) %llu-%llu\n", block, block + count - 1); |
ac27a0ec | 382 | |
3a5b2ecd | 383 | ext4_get_group_no_and_offset(sb, block, &block_group, &bit); |
920313a7 | 384 | grp = ext4_get_group_info(sb, block_group); |
ac27a0ec DK |
385 | /* |
386 | * Check to see if we are freeing blocks across a group | |
387 | * boundary. | |
388 | */ | |
617ba13b | 389 | if (bit + count > EXT4_BLOCKS_PER_GROUP(sb)) { |
e21675d4 | 390 | goto error_return; |
ac27a0ec | 391 | } |
574ca174 | 392 | bitmap_bh = ext4_read_block_bitmap(sb, block_group); |
ac27a0ec DK |
393 | if (!bitmap_bh) |
394 | goto error_return; | |
af5bc92d | 395 | desc = ext4_get_group_desc(sb, block_group, &gd_bh); |
ac27a0ec DK |
396 | if (!desc) |
397 | goto error_return; | |
398 | ||
8fadc143 AR |
399 | if (in_range(ext4_block_bitmap(sb, desc), block, count) || |
400 | in_range(ext4_inode_bitmap(sb, desc), block, count) || | |
401 | in_range(block, ext4_inode_table(sb, desc), sbi->s_itb_per_group) || | |
402 | in_range(block + count - 1, ext4_inode_table(sb, desc), | |
cb47dce7 | 403 | sbi->s_itb_per_group)) { |
e21675d4 AK |
404 | ext4_error(sb, __func__, |
405 | "Adding blocks in system zones - " | |
af5bc92d TT |
406 | "Block = %llu, count = %lu", |
407 | block, count); | |
cb47dce7 AK |
408 | goto error_return; |
409 | } | |
ac27a0ec DK |
410 | |
411 | /* | |
e21675d4 | 412 | * We are about to add blocks to the bitmap, |
ac27a0ec DK |
413 | * so we need undo access. |
414 | */ | |
ac27a0ec | 415 | BUFFER_TRACE(bitmap_bh, "getting undo access"); |
617ba13b | 416 | err = ext4_journal_get_undo_access(handle, bitmap_bh); |
ac27a0ec DK |
417 | if (err) |
418 | goto error_return; | |
419 | ||
420 | /* | |
421 | * We are about to modify some metadata. Call the journal APIs | |
422 | * to unshare ->b_data if a currently-committing transaction is | |
423 | * using it | |
424 | */ | |
425 | BUFFER_TRACE(gd_bh, "get_write_access"); | |
617ba13b | 426 | err = ext4_journal_get_write_access(handle, gd_bh); |
ac27a0ec DK |
427 | if (err) |
428 | goto error_return; | |
920313a7 AK |
429 | /* |
430 | * make sure we don't allow a parallel init on other groups in the | |
431 | * same buddy cache | |
432 | */ | |
433 | down_write(&grp->alloc_sem); | |
e21675d4 | 434 | for (i = 0, blocks_freed = 0; i < count; i++) { |
ac27a0ec | 435 | BUFFER_TRACE(bitmap_bh, "clear bit"); |
617ba13b | 436 | if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group), |
ac27a0ec | 437 | bit + i, bitmap_bh->b_data)) { |
46e665e9 | 438 | ext4_error(sb, __func__, |
2ae02107 | 439 | "bit already cleared for block %llu", |
bd81d8ee | 440 | (ext4_fsblk_t)(block + i)); |
ac27a0ec DK |
441 | BUFFER_TRACE(bitmap_bh, "bit already cleared"); |
442 | } else { | |
e21675d4 | 443 | blocks_freed++; |
ac27a0ec DK |
444 | } |
445 | } | |
ac27a0ec | 446 | spin_lock(sb_bgl_lock(sbi, block_group)); |
560671a0 AK |
447 | blk_free_count = blocks_freed + ext4_free_blks_count(sb, desc); |
448 | ext4_free_blks_set(sb, desc, blk_free_count); | |
717d50e4 | 449 | desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc); |
ac27a0ec | 450 | spin_unlock(sb_bgl_lock(sbi, block_group)); |
e21675d4 | 451 | percpu_counter_add(&sbi->s_freeblocks_counter, blocks_freed); |
ac27a0ec | 452 | |
772cb7c8 JS |
453 | if (sbi->s_log_groups_per_flex) { |
454 | ext4_group_t flex_group = ext4_flex_group(sbi, block_group); | |
455 | spin_lock(sb_bgl_lock(sbi, flex_group)); | |
e21675d4 | 456 | sbi->s_flex_groups[flex_group].free_blocks += blocks_freed; |
772cb7c8 JS |
457 | spin_unlock(sb_bgl_lock(sbi, flex_group)); |
458 | } | |
920313a7 AK |
459 | /* |
460 | * request to reload the buddy with the | |
461 | * new bitmap information | |
462 | */ | |
463 | set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &(grp->bb_state)); | |
464 | ext4_mb_update_group_info(grp, blocks_freed); | |
465 | up_write(&grp->alloc_sem); | |
772cb7c8 | 466 | |
ac27a0ec DK |
467 | /* We dirtied the bitmap block */ |
468 | BUFFER_TRACE(bitmap_bh, "dirtied bitmap block"); | |
0390131b | 469 | err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh); |
ac27a0ec DK |
470 | |
471 | /* And the group descriptor block */ | |
472 | BUFFER_TRACE(gd_bh, "dirtied group descriptor block"); | |
0390131b | 473 | ret = ext4_handle_dirty_metadata(handle, NULL, gd_bh); |
e21675d4 AK |
474 | if (!err) |
475 | err = ret; | |
ac27a0ec | 476 | sb->s_dirt = 1; |
e21675d4 | 477 | |
ac27a0ec DK |
478 | error_return: |
479 | brelse(bitmap_bh); | |
617ba13b | 480 | ext4_std_error(sb, err); |
ac27a0ec DK |
481 | return; |
482 | } | |
483 | ||
484 | /** | |
617ba13b | 485 | * ext4_free_blocks() -- Free given blocks and update quota |
ac27a0ec DK |
486 | * @handle: handle for this transaction |
487 | * @inode: inode | |
488 | * @block: start physical block to free | |
489 | * @count: number of blocks to count | |
c9de560d | 490 | * @metadata: Are these metadata blocks |
ac27a0ec | 491 | */ |
617ba13b | 492 | void ext4_free_blocks(handle_t *handle, struct inode *inode, |
c9de560d AT |
493 | ext4_fsblk_t block, unsigned long count, |
494 | int metadata) | |
ac27a0ec | 495 | { |
af5bc92d | 496 | struct super_block *sb; |
ac27a0ec DK |
497 | unsigned long dquot_freed_blocks; |
498 | ||
c9de560d AT |
499 | /* this isn't the right place to decide whether block is metadata |
500 | * inode.c/extents.c knows better, but for safety ... */ | |
a1aebc1e AK |
501 | if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) |
502 | metadata = 1; | |
503 | ||
504 | /* We need to make sure we don't reuse | |
505 | * block released untill the transaction commit. | |
506 | * writeback mode have weak data consistency so | |
507 | * don't force data as metadata when freeing block | |
508 | * for writeback mode. | |
509 | */ | |
510 | if (metadata == 0 && !ext4_should_writeback_data(inode)) | |
c9de560d AT |
511 | metadata = 1; |
512 | ||
ac27a0ec | 513 | sb = inode->i_sb; |
c9de560d | 514 | |
c2ea3fde TT |
515 | ext4_mb_free_blocks(handle, inode, block, count, |
516 | metadata, &dquot_freed_blocks); | |
ac27a0ec DK |
517 | if (dquot_freed_blocks) |
518 | DQUOT_FREE_BLOCK(inode, dquot_freed_blocks); | |
519 | return; | |
520 | } | |
521 | ||
8c3bf8a0 ES |
522 | /** |
523 | * ext4_has_free_blocks() | |
524 | * @sbi: in-core super block structure. | |
525 | * @nblocks: number of needed blocks | |
526 | * | |
527 | * Check if filesystem has nblocks free & available for allocation. | |
528 | * On success return 1, return 0 on failure. | |
529 | */ | |
530 | int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks) | |
a30d542a | 531 | { |
a996031c | 532 | s64 free_blocks, dirty_blocks, root_blocks; |
a30d542a | 533 | struct percpu_counter *fbc = &sbi->s_freeblocks_counter; |
6bc6e63f | 534 | struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter; |
a30d542a | 535 | |
6bc6e63f AK |
536 | free_blocks = percpu_counter_read_positive(fbc); |
537 | dirty_blocks = percpu_counter_read_positive(dbc); | |
a996031c | 538 | root_blocks = ext4_r_blocks_count(sbi->s_es); |
a30d542a | 539 | |
6bc6e63f AK |
540 | if (free_blocks - (nblocks + root_blocks + dirty_blocks) < |
541 | EXT4_FREEBLOCKS_WATERMARK) { | |
02d21168 AM |
542 | free_blocks = percpu_counter_sum_positive(fbc); |
543 | dirty_blocks = percpu_counter_sum_positive(dbc); | |
6bc6e63f AK |
544 | if (dirty_blocks < 0) { |
545 | printk(KERN_CRIT "Dirty block accounting " | |
546 | "went wrong %lld\n", | |
8f72fbdf | 547 | (long long)dirty_blocks); |
6bc6e63f AK |
548 | } |
549 | } | |
550 | /* Check whether we have space after | |
a996031c | 551 | * accounting for current dirty blocks & root reserved blocks. |
6bc6e63f | 552 | */ |
a996031c ES |
553 | if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks)) |
554 | return 1; | |
a30d542a | 555 | |
a996031c | 556 | /* Hm, nope. Are (enough) root reserved blocks available? */ |
4c9c544e | 557 | if (sbi->s_resuid == current_fsuid() || |
a996031c ES |
558 | ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) || |
559 | capable(CAP_SYS_RESOURCE)) { | |
560 | if (free_blocks >= (nblocks + dirty_blocks)) | |
561 | return 1; | |
562 | } | |
563 | ||
564 | return 0; | |
a30d542a AK |
565 | } |
566 | ||
8c3bf8a0 | 567 | int ext4_claim_free_blocks(struct ext4_sb_info *sbi, |
5c791616 | 568 | s64 nblocks) |
ac27a0ec | 569 | { |
8c3bf8a0 ES |
570 | if (ext4_has_free_blocks(sbi, nblocks)) { |
571 | percpu_counter_add(&sbi->s_dirtyblocks_counter, nblocks); | |
16eb7295 | 572 | return 0; |
8c3bf8a0 ES |
573 | } else |
574 | return -ENOSPC; | |
a30d542a | 575 | } |
07031431 | 576 | |
ac27a0ec | 577 | /** |
617ba13b | 578 | * ext4_should_retry_alloc() |
ac27a0ec DK |
579 | * @sb: super block |
580 | * @retries number of attemps has been made | |
581 | * | |
617ba13b | 582 | * ext4_should_retry_alloc() is called when ENOSPC is returned, and if |
ac27a0ec DK |
583 | * it is profitable to retry the operation, this function will wait |
584 | * for the current or commiting transaction to complete, and then | |
585 | * return TRUE. | |
586 | * | |
587 | * if the total number of retries exceed three times, return FALSE. | |
588 | */ | |
617ba13b | 589 | int ext4_should_retry_alloc(struct super_block *sb, int *retries) |
ac27a0ec | 590 | { |
07031431 | 591 | if (!ext4_has_free_blocks(EXT4_SB(sb), 1) || (*retries)++ > 3) |
ac27a0ec DK |
592 | return 0; |
593 | ||
594 | jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id); | |
595 | ||
dab291af | 596 | return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal); |
ac27a0ec DK |
597 | } |
598 | ||
654b4908 | 599 | /* |
d2a17637 | 600 | * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks |
654b4908 AK |
601 | * |
602 | * @handle: handle to this transaction | |
603 | * @inode: file inode | |
604 | * @goal: given target block(filesystem wide) | |
97df5d15 | 605 | * @count: pointer to total number of blocks needed |
654b4908 AK |
606 | * @errp: error code |
607 | * | |
97df5d15 | 608 | * Return 1st allocated block number on success, *count stores total account |
d2a17637 | 609 | * error stores in errp pointer |
654b4908 | 610 | */ |
d2a17637 MC |
611 | ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode, |
612 | ext4_fsblk_t goal, unsigned long *count, int *errp) | |
654b4908 | 613 | { |
97df5d15 | 614 | struct ext4_allocation_request ar; |
d2a17637 | 615 | ext4_fsblk_t ret; |
97df5d15 TT |
616 | |
617 | memset(&ar, 0, sizeof(ar)); | |
618 | /* Fill with neighbour allocated blocks */ | |
619 | ar.inode = inode; | |
620 | ar.goal = goal; | |
621 | ar.len = count ? *count : 1; | |
622 | ||
623 | ret = ext4_mb_new_blocks(handle, &ar, errp); | |
624 | if (count) | |
625 | *count = ar.len; | |
626 | ||
d2a17637 MC |
627 | /* |
628 | * Account for the allocated meta blocks | |
629 | */ | |
166348dd | 630 | if (!(*errp) && EXT4_I(inode)->i_delalloc_reserved_flag) { |
d2a17637 | 631 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
97df5d15 | 632 | EXT4_I(inode)->i_allocated_meta_blocks += ar.len; |
d2a17637 MC |
633 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
634 | } | |
635 | return ret; | |
654b4908 AK |
636 | } |
637 | ||
ac27a0ec | 638 | /** |
617ba13b | 639 | * ext4_count_free_blocks() -- count filesystem free blocks |
ac27a0ec DK |
640 | * @sb: superblock |
641 | * | |
642 | * Adds up the number of free blocks from each block group. | |
643 | */ | |
617ba13b | 644 | ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb) |
ac27a0ec | 645 | { |
617ba13b MC |
646 | ext4_fsblk_t desc_count; |
647 | struct ext4_group_desc *gdp; | |
fd2d4291 AM |
648 | ext4_group_t i; |
649 | ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count; | |
617ba13b MC |
650 | #ifdef EXT4FS_DEBUG |
651 | struct ext4_super_block *es; | |
652 | ext4_fsblk_t bitmap_count; | |
498e5f24 | 653 | unsigned int x; |
ac27a0ec DK |
654 | struct buffer_head *bitmap_bh = NULL; |
655 | ||
617ba13b | 656 | es = EXT4_SB(sb)->s_es; |
ac27a0ec DK |
657 | desc_count = 0; |
658 | bitmap_count = 0; | |
659 | gdp = NULL; | |
660 | ||
661 | smp_rmb(); | |
662 | for (i = 0; i < ngroups; i++) { | |
617ba13b | 663 | gdp = ext4_get_group_desc(sb, i, NULL); |
ac27a0ec DK |
664 | if (!gdp) |
665 | continue; | |
666 | desc_count += le16_to_cpu(gdp->bg_free_blocks_count); | |
667 | brelse(bitmap_bh); | |
574ca174 | 668 | bitmap_bh = ext4_read_block_bitmap(sb, i); |
ac27a0ec DK |
669 | if (bitmap_bh == NULL) |
670 | continue; | |
671 | ||
617ba13b | 672 | x = ext4_count_free(bitmap_bh, sb->s_blocksize); |
498e5f24 | 673 | printk(KERN_DEBUG "group %lu: stored = %d, counted = %u\n", |
ac27a0ec DK |
674 | i, le16_to_cpu(gdp->bg_free_blocks_count), x); |
675 | bitmap_count += x; | |
676 | } | |
677 | brelse(bitmap_bh); | |
4776004f TT |
678 | printk(KERN_DEBUG "ext4_count_free_blocks: stored = %llu" |
679 | ", computed = %llu, %llu\n", ext4_free_blocks_count(es), | |
680 | desc_count, bitmap_count); | |
ac27a0ec DK |
681 | return bitmap_count; |
682 | #else | |
683 | desc_count = 0; | |
684 | smp_rmb(); | |
685 | for (i = 0; i < ngroups; i++) { | |
617ba13b | 686 | gdp = ext4_get_group_desc(sb, i, NULL); |
ac27a0ec DK |
687 | if (!gdp) |
688 | continue; | |
560671a0 | 689 | desc_count += ext4_free_blks_count(sb, gdp); |
ac27a0ec DK |
690 | } |
691 | ||
692 | return desc_count; | |
693 | #endif | |
694 | } | |
695 | ||
fd2d4291 | 696 | static inline int test_root(ext4_group_t a, int b) |
ac27a0ec DK |
697 | { |
698 | int num = b; | |
699 | ||
700 | while (a > num) | |
701 | num *= b; | |
702 | return num == a; | |
703 | } | |
704 | ||
fd2d4291 | 705 | static int ext4_group_sparse(ext4_group_t group) |
ac27a0ec DK |
706 | { |
707 | if (group <= 1) | |
708 | return 1; | |
709 | if (!(group & 1)) | |
710 | return 0; | |
711 | return (test_root(group, 7) || test_root(group, 5) || | |
712 | test_root(group, 3)); | |
713 | } | |
714 | ||
715 | /** | |
617ba13b | 716 | * ext4_bg_has_super - number of blocks used by the superblock in group |
ac27a0ec DK |
717 | * @sb: superblock for filesystem |
718 | * @group: group number to check | |
719 | * | |
720 | * Return the number of blocks used by the superblock (primary or backup) | |
721 | * in this group. Currently this will be only 0 or 1. | |
722 | */ | |
fd2d4291 | 723 | int ext4_bg_has_super(struct super_block *sb, ext4_group_t group) |
ac27a0ec | 724 | { |
617ba13b MC |
725 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, |
726 | EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) && | |
727 | !ext4_group_sparse(group)) | |
ac27a0ec DK |
728 | return 0; |
729 | return 1; | |
730 | } | |
731 | ||
fd2d4291 AM |
732 | static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, |
733 | ext4_group_t group) | |
ac27a0ec | 734 | { |
617ba13b | 735 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
fd2d4291 AM |
736 | ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb); |
737 | ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1; | |
ac27a0ec DK |
738 | |
739 | if (group == first || group == first + 1 || group == last) | |
740 | return 1; | |
741 | return 0; | |
742 | } | |
743 | ||
fd2d4291 AM |
744 | static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, |
745 | ext4_group_t group) | |
ac27a0ec | 746 | { |
859cb936 | 747 | return ext4_bg_has_super(sb, group) ? EXT4_SB(sb)->s_gdb_count : 0; |
ac27a0ec DK |
748 | } |
749 | ||
750 | /** | |
617ba13b | 751 | * ext4_bg_num_gdb - number of blocks used by the group table in group |
ac27a0ec DK |
752 | * @sb: superblock for filesystem |
753 | * @group: group number to check | |
754 | * | |
755 | * Return the number of blocks used by the group descriptor table | |
756 | * (primary or backup) in this group. In the future there may be a | |
757 | * different number of descriptor blocks in each group. | |
758 | */ | |
fd2d4291 | 759 | unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group) |
ac27a0ec DK |
760 | { |
761 | unsigned long first_meta_bg = | |
617ba13b MC |
762 | le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
763 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); | |
ac27a0ec | 764 | |
617ba13b | 765 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) || |
ac27a0ec | 766 | metagroup < first_meta_bg) |
af5bc92d | 767 | return ext4_bg_num_gdb_nometa(sb, group); |
ac27a0ec | 768 | |
617ba13b | 769 | return ext4_bg_num_gdb_meta(sb,group); |
ac27a0ec DK |
770 | |
771 | } | |
c2ea3fde | 772 |