Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 1 | /* |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 2 | * linux/fs/ext4/balloc.c |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 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> |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 17 | #include <linux/jbd2.h> |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 18 | #include <linux/quotaops.h> |
| 19 | #include <linux/buffer_head.h> |
Christoph Hellwig | 3dcf545 | 2008-04-29 18:13:32 -0400 | [diff] [blame] | 20 | #include "ext4.h" |
| 21 | #include "ext4_jbd2.h" |
Aneesh Kumar K.V | e21675d | 2009-01-05 21:36:02 -0500 | [diff] [blame] | 22 | #include "mballoc.h" |
Christoph Hellwig | 3dcf545 | 2008-04-29 18:13:32 -0400 | [diff] [blame] | 23 | |
Jiaying Zhang | 0562e0b | 2011-03-21 21:38:05 -0400 | [diff] [blame] | 24 | #include <trace/events/ext4.h> |
| 25 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 26 | /* |
| 27 | * balloc.c contains the blocks allocation and deallocation routines |
| 28 | */ |
| 29 | |
| 30 | /* |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 31 | * Calculate the block group number and offset, given a block number |
| 32 | */ |
| 33 | void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr, |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 34 | ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp) |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 35 | { |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 36 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 37 | ext4_grpblk_t offset; |
| 38 | |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 39 | blocknr = blocknr - le32_to_cpu(es->s_first_data_block); |
Andrew Morton | f4e5bc2 | 2006-10-11 01:21:19 -0700 | [diff] [blame] | 40 | offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)); |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 41 | if (offsetp) |
| 42 | *offsetp = offset; |
| 43 | if (blockgrpp) |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 44 | *blockgrpp = blocknr; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 45 | |
| 46 | } |
| 47 | |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 48 | static int ext4_block_in_group(struct super_block *sb, ext4_fsblk_t block, |
| 49 | ext4_group_t block_group) |
| 50 | { |
| 51 | ext4_group_t actual_group; |
Aneesh Kumar K.V | 7477827 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 52 | ext4_get_group_no_and_offset(sb, block, &actual_group, NULL); |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 53 | if (actual_group == block_group) |
| 54 | return 1; |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | static int ext4_group_used_meta_blocks(struct super_block *sb, |
Theodore Ts'o | e187c65 | 2009-02-06 16:23:37 -0500 | [diff] [blame] | 59 | ext4_group_t block_group, |
| 60 | struct ext4_group_desc *gdp) |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 61 | { |
| 62 | ext4_fsblk_t tmp; |
| 63 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 64 | /* block bitmap, inode bitmap, and inode table blocks */ |
| 65 | int used_blocks = sbi->s_itb_per_group + 2; |
| 66 | |
| 67 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 68 | if (!ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), |
| 69 | block_group)) |
| 70 | used_blocks--; |
| 71 | |
| 72 | if (!ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), |
| 73 | block_group)) |
| 74 | used_blocks--; |
| 75 | |
| 76 | tmp = ext4_inode_table(sb, gdp); |
| 77 | for (; tmp < ext4_inode_table(sb, gdp) + |
| 78 | sbi->s_itb_per_group; tmp++) { |
| 79 | if (!ext4_block_in_group(sb, tmp, block_group)) |
| 80 | used_blocks -= 1; |
| 81 | } |
| 82 | } |
| 83 | return used_blocks; |
| 84 | } |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 85 | |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 86 | /* Initializes an uninitialized block bitmap if given, and returns the |
| 87 | * number of blocks free in the group. */ |
| 88 | unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 89 | ext4_group_t block_group, struct ext4_group_desc *gdp) |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 90 | { |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 91 | int bit, bit_max; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 92 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 93 | unsigned free_blocks, group_blocks; |
| 94 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 95 | |
| 96 | if (bh) { |
| 97 | J_ASSERT_BH(bh, buffer_locked(bh)); |
| 98 | |
| 99 | /* If checksum is bad mark all blocks used to prevent allocation |
| 100 | * essentially implementing a per-group read-only flag. */ |
| 101 | if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 102 | ext4_error(sb, "Checksum bad for group %u", |
| 103 | block_group); |
Aneesh Kumar K.V | 560671a | 2009-01-05 22:20:24 -0500 | [diff] [blame] | 104 | ext4_free_blks_set(sb, gdp, 0); |
| 105 | ext4_free_inodes_set(sb, gdp, 0); |
| 106 | ext4_itable_unused_set(sb, gdp, 0); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 107 | memset(bh->b_data, 0xff, sb->s_blocksize); |
| 108 | return 0; |
| 109 | } |
| 110 | memset(bh->b_data, 0, sb->s_blocksize); |
| 111 | } |
| 112 | |
| 113 | /* Check for superblock and gdt backups in this group */ |
| 114 | bit_max = ext4_bg_has_super(sb, block_group); |
| 115 | |
| 116 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) || |
| 117 | block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) * |
| 118 | sbi->s_desc_per_block) { |
| 119 | if (bit_max) { |
| 120 | bit_max += ext4_bg_num_gdb(sb, block_group); |
| 121 | bit_max += |
| 122 | le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks); |
| 123 | } |
| 124 | } else { /* For META_BG_BLOCK_GROUPS */ |
Akinobu Mita | 6afd670 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 125 | bit_max += ext4_bg_num_gdb(sb, block_group); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 126 | } |
| 127 | |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 128 | if (block_group == ngroups - 1) { |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 129 | /* |
| 130 | * Even though mke2fs always initialize first and last group |
| 131 | * if some other tool enabled the EXT4_BG_BLOCK_UNINIT we need |
| 132 | * to make sure we calculate the right free blocks |
| 133 | */ |
| 134 | group_blocks = ext4_blocks_count(sbi->s_es) - |
Akinobu Mita | 5661bd6 | 2010-03-03 23:53:39 -0500 | [diff] [blame] | 135 | ext4_group_first_block_no(sb, ngroups - 1); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 136 | } else { |
| 137 | group_blocks = EXT4_BLOCKS_PER_GROUP(sb); |
| 138 | } |
| 139 | |
| 140 | free_blocks = group_blocks - bit_max; |
| 141 | |
| 142 | if (bh) { |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 143 | ext4_fsblk_t start, tmp; |
| 144 | int flex_bg = 0; |
Akinobu Mita | d00a6d7 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 145 | |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 146 | for (bit = 0; bit < bit_max; bit++) |
| 147 | ext4_set_bit(bit, bh->b_data); |
| 148 | |
Akinobu Mita | d00a6d7 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 149 | start = ext4_group_first_block_no(sb, block_group); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 150 | |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 151 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, |
| 152 | EXT4_FEATURE_INCOMPAT_FLEX_BG)) |
| 153 | flex_bg = 1; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 154 | |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 155 | /* Set bits for block and inode bitmaps, and inode table */ |
| 156 | tmp = ext4_block_bitmap(sb, gdp); |
| 157 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
| 158 | ext4_set_bit(tmp - start, bh->b_data); |
| 159 | |
| 160 | tmp = ext4_inode_bitmap(sb, gdp); |
| 161 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
| 162 | ext4_set_bit(tmp - start, bh->b_data); |
| 163 | |
| 164 | tmp = ext4_inode_table(sb, gdp); |
| 165 | for (; tmp < ext4_inode_table(sb, gdp) + |
| 166 | sbi->s_itb_per_group; tmp++) { |
| 167 | if (!flex_bg || |
| 168 | ext4_block_in_group(sb, tmp, block_group)) |
| 169 | ext4_set_bit(tmp - start, bh->b_data); |
| 170 | } |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 171 | /* |
| 172 | * Also if the number of blocks within the group is |
| 173 | * less than the blocksize * 8 ( which is the size |
| 174 | * of bitmap ), set rest of the block bitmap to 1 |
| 175 | */ |
Theodore Ts'o | 61d0867 | 2010-10-27 21:30:15 -0400 | [diff] [blame] | 176 | ext4_mark_bitmap_end(group_blocks, sb->s_blocksize * 8, |
| 177 | bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 178 | } |
Theodore Ts'o | e187c65 | 2009-02-06 16:23:37 -0500 | [diff] [blame] | 179 | return free_blocks - ext4_group_used_meta_blocks(sb, block_group, gdp); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 180 | } |
| 181 | |
| 182 | |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 183 | /* |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 184 | * The free blocks are managed by bitmaps. A file system contains several |
| 185 | * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap |
| 186 | * block for inodes, N blocks for the inode table and data blocks. |
| 187 | * |
| 188 | * The file system contains group descriptors which are located after the |
| 189 | * super block. Each descriptor contains the number of the bitmap block and |
| 190 | * the free blocks count in the block. The descriptors are loaded in memory |
Aneesh Kumar K.V | e627432 | 2007-02-20 13:57:58 -0800 | [diff] [blame] | 191 | * when a file system is mounted (see ext4_fill_super). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 192 | */ |
| 193 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 194 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 195 | * ext4_get_group_desc() -- load group descriptor from disk |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 196 | * @sb: super block |
| 197 | * @block_group: given block group |
| 198 | * @bh: pointer to the buffer head to store the block |
| 199 | * group descriptor |
| 200 | */ |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 201 | struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 202 | ext4_group_t block_group, |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 203 | struct buffer_head **bh) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 204 | { |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 205 | unsigned int group_desc; |
| 206 | unsigned int offset; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 207 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 208 | struct ext4_group_desc *desc; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 209 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 210 | |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 211 | if (block_group >= ngroups) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 212 | ext4_error(sb, "block_group >= groups_count - block_group = %u," |
| 213 | " groups_count = %u", block_group, ngroups); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 214 | |
| 215 | return NULL; |
| 216 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 217 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 218 | group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); |
| 219 | offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 220 | if (!sbi->s_group_desc[group_desc]) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 221 | ext4_error(sb, "Group descriptor not loaded - " |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 222 | "block_group = %u, group_desc = %u, desc = %u", |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 223 | block_group, group_desc, offset); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 224 | return NULL; |
| 225 | } |
| 226 | |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 227 | desc = (struct ext4_group_desc *)( |
| 228 | (__u8 *)sbi->s_group_desc[group_desc]->b_data + |
| 229 | offset * EXT4_DESC_SIZE(sb)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 230 | if (bh) |
| 231 | *bh = sbi->s_group_desc[group_desc]; |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 232 | return desc; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 233 | } |
| 234 | |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 235 | static int ext4_valid_block_bitmap(struct super_block *sb, |
| 236 | struct ext4_group_desc *desc, |
| 237 | unsigned int block_group, |
| 238 | struct buffer_head *bh) |
| 239 | { |
| 240 | ext4_grpblk_t offset; |
| 241 | ext4_grpblk_t next_zero_bit; |
| 242 | ext4_fsblk_t bitmap_blk; |
| 243 | ext4_fsblk_t group_first_block; |
| 244 | |
| 245 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { |
| 246 | /* with FLEX_BG, the inode/block bitmaps and itable |
| 247 | * blocks may not be in the group at all |
| 248 | * so the bitmap validation will be skipped for those groups |
| 249 | * or it has to also read the block group where the bitmaps |
| 250 | * are located to verify they are set. |
| 251 | */ |
| 252 | return 1; |
| 253 | } |
| 254 | group_first_block = ext4_group_first_block_no(sb, block_group); |
| 255 | |
| 256 | /* check whether block bitmap block number is set */ |
| 257 | bitmap_blk = ext4_block_bitmap(sb, desc); |
| 258 | offset = bitmap_blk - group_first_block; |
| 259 | if (!ext4_test_bit(offset, bh->b_data)) |
| 260 | /* bad block bitmap */ |
| 261 | goto err_out; |
| 262 | |
| 263 | /* check whether the inode bitmap block number is set */ |
| 264 | bitmap_blk = ext4_inode_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 table block number is set */ |
| 271 | bitmap_blk = ext4_inode_table(sb, desc); |
| 272 | offset = bitmap_blk - group_first_block; |
| 273 | next_zero_bit = ext4_find_next_zero_bit(bh->b_data, |
| 274 | offset + EXT4_SB(sb)->s_itb_per_group, |
| 275 | offset); |
| 276 | if (next_zero_bit >= offset + EXT4_SB(sb)->s_itb_per_group) |
| 277 | /* good bitmap for inode tables */ |
| 278 | return 1; |
| 279 | |
| 280 | err_out: |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 281 | ext4_error(sb, "Invalid block bitmap - block_group = %d, block = %llu", |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 282 | block_group, bitmap_blk); |
| 283 | return 0; |
| 284 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 285 | /** |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 286 | * ext4_read_block_bitmap() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 287 | * @sb: super block |
| 288 | * @block_group: given block group |
| 289 | * |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 290 | * Read the bitmap for a given block_group,and validate the |
| 291 | * bits for block/inode/inode tables are set in the bitmaps |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 292 | * |
| 293 | * Return buffer_head on success or NULL in case of failure. |
| 294 | */ |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 295 | struct buffer_head * |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 296 | ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 297 | { |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 298 | struct ext4_group_desc *desc; |
| 299 | struct buffer_head *bh = NULL; |
Aneesh Kumar K.V | 7c9e69f | 2007-10-16 23:27:02 -0700 | [diff] [blame] | 300 | ext4_fsblk_t bitmap_blk; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 301 | |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 302 | desc = ext4_get_group_desc(sb, block_group, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 303 | if (!desc) |
Aneesh Kumar K.V | 7c9e69f | 2007-10-16 23:27:02 -0700 | [diff] [blame] | 304 | return NULL; |
| 305 | bitmap_blk = ext4_block_bitmap(sb, desc); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 306 | bh = sb_getblk(sb, bitmap_blk); |
| 307 | if (unlikely(!bh)) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 308 | ext4_error(sb, "Cannot read block bitmap - " |
Theodore Ts'o | a9df9a4 | 2009-01-05 22:18:16 -0500 | [diff] [blame] | 309 | "block_group = %u, block_bitmap = %llu", |
Eric Sandeen | e29d1cd | 2008-08-02 21:21:02 -0400 | [diff] [blame] | 310 | block_group, bitmap_blk); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 311 | return NULL; |
| 312 | } |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 313 | |
| 314 | if (bitmap_uptodate(bh)) |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 315 | return bh; |
| 316 | |
Frederic Bohe | c806e68 | 2008-10-10 08:09:18 -0400 | [diff] [blame] | 317 | lock_buffer(bh); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 318 | if (bitmap_uptodate(bh)) { |
| 319 | unlock_buffer(bh); |
| 320 | return bh; |
| 321 | } |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 322 | ext4_lock_group(sb, block_group); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 323 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { |
| 324 | ext4_init_block_bitmap(sb, bh, block_group, desc); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 325 | set_bitmap_uptodate(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 326 | set_buffer_uptodate(bh); |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 327 | ext4_unlock_group(sb, block_group); |
Aneesh Kumar K.V | 3300bed | 2009-01-03 22:33:39 -0500 | [diff] [blame] | 328 | unlock_buffer(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 329 | return bh; |
| 330 | } |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 331 | ext4_unlock_group(sb, block_group); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 332 | if (buffer_uptodate(bh)) { |
| 333 | /* |
| 334 | * if not uninit if bh is uptodate, |
| 335 | * bitmap is also uptodate |
| 336 | */ |
| 337 | set_bitmap_uptodate(bh); |
| 338 | unlock_buffer(bh); |
| 339 | return bh; |
| 340 | } |
| 341 | /* |
| 342 | * submit the buffer_head for read. We can |
| 343 | * safely mark the bitmap as uptodate now. |
| 344 | * We do it here so the bitmap uptodate bit |
| 345 | * get set with buffer lock held. |
| 346 | */ |
Jiaying Zhang | 0562e0b | 2011-03-21 21:38:05 -0400 | [diff] [blame] | 347 | trace_ext4_read_block_bitmap_load(sb, block_group); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 348 | set_bitmap_uptodate(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 349 | if (bh_submit_read(bh) < 0) { |
| 350 | put_bh(bh); |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 351 | ext4_error(sb, "Cannot read block bitmap - " |
Theodore Ts'o | a9df9a4 | 2009-01-05 22:18:16 -0500 | [diff] [blame] | 352 | "block_group = %u, block_bitmap = %llu", |
Eric Sandeen | e29d1cd | 2008-08-02 21:21:02 -0400 | [diff] [blame] | 353 | block_group, bitmap_blk); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 354 | return NULL; |
| 355 | } |
Aneesh Kumar K.V | 519deca | 2008-05-15 14:43:20 -0400 | [diff] [blame] | 356 | ext4_valid_block_bitmap(sb, desc, block_group, bh); |
| 357 | /* |
| 358 | * file system mounted not to panic on error, |
| 359 | * continue with corrupt bitmap |
| 360 | */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 361 | return bh; |
| 362 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 363 | |
| 364 | /** |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 365 | * ext4_has_free_blocks() |
| 366 | * @sbi: in-core super block structure. |
| 367 | * @nblocks: number of needed blocks |
| 368 | * |
| 369 | * Check if filesystem has nblocks free & available for allocation. |
| 370 | * On success return 1, return 0 on failure. |
| 371 | */ |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 372 | static int ext4_has_free_blocks(struct ext4_sb_info *sbi, |
| 373 | s64 nblocks, unsigned int flags) |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 374 | { |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 375 | s64 free_blocks, dirty_blocks, root_blocks; |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 376 | struct percpu_counter *fbc = &sbi->s_freeblocks_counter; |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 377 | struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter; |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 378 | |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 379 | free_blocks = percpu_counter_read_positive(fbc); |
| 380 | dirty_blocks = percpu_counter_read_positive(dbc); |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 381 | root_blocks = ext4_r_blocks_count(sbi->s_es); |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 382 | |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 383 | if (free_blocks - (nblocks + root_blocks + dirty_blocks) < |
| 384 | EXT4_FREEBLOCKS_WATERMARK) { |
Andrew Morton | 02d2116 | 2008-12-09 13:14:14 -0800 | [diff] [blame] | 385 | free_blocks = percpu_counter_sum_positive(fbc); |
| 386 | dirty_blocks = percpu_counter_sum_positive(dbc); |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 387 | } |
| 388 | /* Check whether we have space after |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 389 | * accounting for current dirty blocks & root reserved blocks. |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 390 | */ |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 391 | if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks)) |
| 392 | return 1; |
Aneesh Kumar K.V | 5c79161 | 2008-10-08 23:12:24 -0400 | [diff] [blame] | 393 | |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 394 | /* Hm, nope. Are (enough) root reserved blocks available? */ |
David Howells | 4c9c544 | 2008-11-14 10:38:51 +1100 | [diff] [blame] | 395 | if (sbi->s_resuid == current_fsuid() || |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 396 | ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) || |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 397 | capable(CAP_SYS_RESOURCE) || |
| 398 | (flags & EXT4_MB_USE_ROOT_BLOCKS)) { |
| 399 | |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 400 | if (free_blocks >= (nblocks + dirty_blocks)) |
| 401 | return 1; |
| 402 | } |
| 403 | |
| 404 | return 0; |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 405 | } |
Mingming Cao | 0703143 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 406 | |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 407 | int ext4_claim_free_blocks(struct ext4_sb_info *sbi, |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 408 | s64 nblocks, unsigned int flags) |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 409 | { |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 410 | if (ext4_has_free_blocks(sbi, nblocks, flags)) { |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 411 | percpu_counter_add(&sbi->s_dirtyblocks_counter, nblocks); |
| 412 | return 0; |
| 413 | } else |
| 414 | return -ENOSPC; |
| 415 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 416 | |
| 417 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 418 | * ext4_should_retry_alloc() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 419 | * @sb: super block |
| 420 | * @retries number of attemps has been made |
| 421 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 422 | * ext4_should_retry_alloc() is called when ENOSPC is returned, and if |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 423 | * it is profitable to retry the operation, this function will wait |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 424 | * for the current or committing transaction to complete, and then |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 425 | * return TRUE. |
| 426 | * |
| 427 | * if the total number of retries exceed three times, return FALSE. |
| 428 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 429 | int ext4_should_retry_alloc(struct super_block *sb, int *retries) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 430 | { |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 431 | if (!ext4_has_free_blocks(EXT4_SB(sb), 1, 0) || |
Eric Sandeen | 8f64b32 | 2009-02-26 00:57:35 -0500 | [diff] [blame] | 432 | (*retries)++ > 3 || |
| 433 | !EXT4_SB(sb)->s_journal) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 434 | return 0; |
| 435 | |
| 436 | jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id); |
| 437 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 438 | return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 439 | } |
| 440 | |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 441 | /* |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 442 | * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks |
| 443 | * |
| 444 | * @handle: handle to this transaction |
| 445 | * @inode: file inode |
| 446 | * @goal: given target block(filesystem wide) |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 447 | * @count: pointer to total number of blocks needed |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 448 | * @errp: error code |
| 449 | * |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 450 | * Return 1st allocated block number on success, *count stores total account |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 451 | * error stores in errp pointer |
| 452 | */ |
| 453 | ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode, |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 454 | ext4_fsblk_t goal, unsigned int flags, |
| 455 | unsigned long *count, int *errp) |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 456 | { |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 457 | struct ext4_allocation_request ar; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 458 | ext4_fsblk_t ret; |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 459 | |
| 460 | memset(&ar, 0, sizeof(ar)); |
| 461 | /* Fill with neighbour allocated blocks */ |
| 462 | ar.inode = inode; |
| 463 | ar.goal = goal; |
| 464 | ar.len = count ? *count : 1; |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 465 | ar.flags = flags; |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 466 | |
| 467 | ret = ext4_mb_new_blocks(handle, &ar, errp); |
| 468 | if (count) |
| 469 | *count = ar.len; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 470 | /* |
Eric Sandeen | 72b8ab9 | 2010-05-16 11:00:00 -0400 | [diff] [blame] | 471 | * Account for the allocated meta blocks. We will never |
| 472 | * fail EDQUOT for metdata, but we do account for it. |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 473 | */ |
Theodore Ts'o | f232109 | 2011-01-10 12:12:36 -0500 | [diff] [blame] | 474 | if (!(*errp) && |
| 475 | ext4_test_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED)) { |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 476 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 477 | EXT4_I(inode)->i_allocated_meta_blocks += ar.len; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 478 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
Eric Sandeen | 72b8ab9 | 2010-05-16 11:00:00 -0400 | [diff] [blame] | 479 | dquot_alloc_block_nofail(inode, ar.len); |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 480 | } |
| 481 | return ret; |
| 482 | } |
| 483 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 484 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 485 | * ext4_count_free_blocks() -- count filesystem free blocks |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 486 | * @sb: superblock |
| 487 | * |
| 488 | * Adds up the number of free blocks from each block group. |
| 489 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 490 | ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 491 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 492 | ext4_fsblk_t desc_count; |
| 493 | struct ext4_group_desc *gdp; |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 494 | ext4_group_t i; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 495 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 496 | #ifdef EXT4FS_DEBUG |
| 497 | struct ext4_super_block *es; |
| 498 | ext4_fsblk_t bitmap_count; |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 499 | unsigned int x; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 500 | struct buffer_head *bitmap_bh = NULL; |
| 501 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 502 | es = EXT4_SB(sb)->s_es; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 503 | desc_count = 0; |
| 504 | bitmap_count = 0; |
| 505 | gdp = NULL; |
| 506 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 507 | for (i = 0; i < ngroups; i++) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 508 | gdp = ext4_get_group_desc(sb, i, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 509 | if (!gdp) |
| 510 | continue; |
Thadeu Lima de Souza Cascardo | 9fd9784 | 2009-01-26 19:26:26 -0500 | [diff] [blame] | 511 | desc_count += ext4_free_blks_count(sb, gdp); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 512 | brelse(bitmap_bh); |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 513 | bitmap_bh = ext4_read_block_bitmap(sb, i); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 514 | if (bitmap_bh == NULL) |
| 515 | continue; |
| 516 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 517 | x = ext4_count_free(bitmap_bh, sb->s_blocksize); |
Thadeu Lima de Souza Cascardo | 9fd9784 | 2009-01-26 19:26:26 -0500 | [diff] [blame] | 518 | printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n", |
| 519 | i, ext4_free_blks_count(sb, gdp), x); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 520 | bitmap_count += x; |
| 521 | } |
| 522 | brelse(bitmap_bh); |
Theodore Ts'o | 4776004f | 2008-09-08 23:00:52 -0400 | [diff] [blame] | 523 | printk(KERN_DEBUG "ext4_count_free_blocks: stored = %llu" |
| 524 | ", computed = %llu, %llu\n", ext4_free_blocks_count(es), |
| 525 | desc_count, bitmap_count); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 526 | return bitmap_count; |
| 527 | #else |
| 528 | desc_count = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 529 | for (i = 0; i < ngroups; i++) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 530 | gdp = ext4_get_group_desc(sb, i, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 531 | if (!gdp) |
| 532 | continue; |
Aneesh Kumar K.V | 560671a | 2009-01-05 22:20:24 -0500 | [diff] [blame] | 533 | desc_count += ext4_free_blks_count(sb, gdp); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 534 | } |
| 535 | |
| 536 | return desc_count; |
| 537 | #endif |
| 538 | } |
| 539 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 540 | static inline int test_root(ext4_group_t a, int b) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 541 | { |
| 542 | int num = b; |
| 543 | |
| 544 | while (a > num) |
| 545 | num *= b; |
| 546 | return num == a; |
| 547 | } |
| 548 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 549 | static int ext4_group_sparse(ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 550 | { |
| 551 | if (group <= 1) |
| 552 | return 1; |
| 553 | if (!(group & 1)) |
| 554 | return 0; |
| 555 | return (test_root(group, 7) || test_root(group, 5) || |
| 556 | test_root(group, 3)); |
| 557 | } |
| 558 | |
| 559 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 560 | * ext4_bg_has_super - number of blocks used by the superblock in group |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 561 | * @sb: superblock for filesystem |
| 562 | * @group: group number to check |
| 563 | * |
| 564 | * Return the number of blocks used by the superblock (primary or backup) |
| 565 | * in this group. Currently this will be only 0 or 1. |
| 566 | */ |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 567 | int ext4_bg_has_super(struct super_block *sb, ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 568 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 569 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, |
| 570 | EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) && |
| 571 | !ext4_group_sparse(group)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 572 | return 0; |
| 573 | return 1; |
| 574 | } |
| 575 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 576 | static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, |
| 577 | ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 578 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 579 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 580 | ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb); |
| 581 | ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 582 | |
| 583 | if (group == first || group == first + 1 || group == last) |
| 584 | return 1; |
| 585 | return 0; |
| 586 | } |
| 587 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 588 | static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, |
| 589 | ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 590 | { |
Theodore Ts'o | 8dadb19 | 2009-11-23 07:24:38 -0500 | [diff] [blame] | 591 | if (!ext4_bg_has_super(sb, group)) |
| 592 | return 0; |
| 593 | |
| 594 | if (EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG)) |
| 595 | return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
| 596 | else |
| 597 | return EXT4_SB(sb)->s_gdb_count; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 598 | } |
| 599 | |
| 600 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 601 | * ext4_bg_num_gdb - number of blocks used by the group table in group |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 602 | * @sb: superblock for filesystem |
| 603 | * @group: group number to check |
| 604 | * |
| 605 | * Return the number of blocks used by the group descriptor table |
| 606 | * (primary or backup) in this group. In the future there may be a |
| 607 | * different number of descriptor blocks in each group. |
| 608 | */ |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 609 | unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 610 | { |
| 611 | unsigned long first_meta_bg = |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 612 | le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
| 613 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 614 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 615 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) || |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 616 | metagroup < first_meta_bg) |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 617 | return ext4_bg_num_gdb_nometa(sb, group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 618 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 619 | return ext4_bg_num_gdb_meta(sb,group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 620 | |
| 621 | } |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 622 | |