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 | |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 26 | static unsigned int num_base_meta_blocks(struct super_block *sb, |
| 27 | ext4_group_t block_group); |
| 28 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 29 | /* |
| 30 | * balloc.c contains the blocks allocation and deallocation routines |
| 31 | */ |
| 32 | |
| 33 | /* |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 34 | * Calculate the block group number and offset, given a block number |
| 35 | */ |
| 36 | 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] | 37 | ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp) |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 38 | { |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 39 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 40 | ext4_grpblk_t offset; |
| 41 | |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 42 | blocknr = blocknr - le32_to_cpu(es->s_first_data_block); |
Andrew Morton | f4e5bc2 | 2006-10-11 01:21:19 -0700 | [diff] [blame] | 43 | offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)); |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 44 | if (offsetp) |
| 45 | *offsetp = offset; |
| 46 | if (blockgrpp) |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 47 | *blockgrpp = blocknr; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 48 | |
| 49 | } |
| 50 | |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 51 | static int ext4_block_in_group(struct super_block *sb, ext4_fsblk_t block, |
| 52 | ext4_group_t block_group) |
| 53 | { |
| 54 | ext4_group_t actual_group; |
Aneesh Kumar K.V | 7477827 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 55 | ext4_get_group_no_and_offset(sb, block, &actual_group, NULL); |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 56 | if (actual_group == block_group) |
| 57 | return 1; |
| 58 | return 0; |
| 59 | } |
| 60 | |
| 61 | static int ext4_group_used_meta_blocks(struct super_block *sb, |
Theodore Ts'o | e187c65 | 2009-02-06 16:23:37 -0500 | [diff] [blame] | 62 | ext4_group_t block_group, |
| 63 | struct ext4_group_desc *gdp) |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 64 | { |
| 65 | ext4_fsblk_t tmp; |
| 66 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 67 | /* block bitmap, inode bitmap, and inode table blocks */ |
| 68 | int used_blocks = sbi->s_itb_per_group + 2; |
| 69 | |
| 70 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 71 | if (!ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), |
| 72 | block_group)) |
| 73 | used_blocks--; |
| 74 | |
| 75 | if (!ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), |
| 76 | block_group)) |
| 77 | used_blocks--; |
| 78 | |
| 79 | tmp = ext4_inode_table(sb, gdp); |
| 80 | for (; tmp < ext4_inode_table(sb, gdp) + |
| 81 | sbi->s_itb_per_group; tmp++) { |
| 82 | if (!ext4_block_in_group(sb, tmp, block_group)) |
| 83 | used_blocks -= 1; |
| 84 | } |
| 85 | } |
| 86 | return used_blocks; |
| 87 | } |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 88 | |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 89 | static unsigned int num_blocks_in_group(struct super_block *sb, |
| 90 | ext4_group_t block_group) |
| 91 | { |
| 92 | if (block_group == ext4_get_groups_count(sb) - 1) { |
| 93 | /* |
| 94 | * Even though mke2fs always initializes the first and |
| 95 | * last group, just in case some other tool was used, |
| 96 | * we need to make sure we calculate the right free |
| 97 | * blocks. |
| 98 | */ |
| 99 | return ext4_blocks_count(EXT4_SB(sb)->s_es) - |
| 100 | ext4_group_first_block_no(sb, block_group); |
| 101 | } else |
| 102 | return EXT4_BLOCKS_PER_GROUP(sb); |
| 103 | } |
| 104 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 105 | /* Initializes an uninitialized block bitmap */ |
| 106 | void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, |
| 107 | ext4_group_t block_group, |
| 108 | struct ext4_group_desc *gdp) |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 109 | { |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 110 | unsigned int bit, bit_max = num_base_meta_blocks(sb, block_group); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 111 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 112 | ext4_fsblk_t start, tmp; |
| 113 | int flex_bg = 0; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 114 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 115 | J_ASSERT_BH(bh, buffer_locked(bh)); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 116 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 117 | /* If checksum is bad mark all blocks used to prevent allocation |
| 118 | * essentially implementing a per-group read-only flag. */ |
| 119 | if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { |
| 120 | ext4_error(sb, "Checksum bad for group %u", block_group); |
| 121 | ext4_free_blks_set(sb, gdp, 0); |
| 122 | ext4_free_inodes_set(sb, gdp, 0); |
| 123 | ext4_itable_unused_set(sb, gdp, 0); |
| 124 | memset(bh->b_data, 0xff, sb->s_blocksize); |
| 125 | return; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 126 | } |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 127 | memset(bh->b_data, 0, sb->s_blocksize); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 128 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 129 | for (bit = 0; bit < bit_max; bit++) |
| 130 | ext4_set_bit(bit, bh->b_data); |
Akinobu Mita | d00a6d7 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 131 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 132 | start = ext4_group_first_block_no(sb, block_group); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 133 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 134 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) |
| 135 | flex_bg = 1; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 136 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 137 | /* Set bits for block and inode bitmaps, and inode table */ |
| 138 | tmp = ext4_block_bitmap(sb, gdp); |
| 139 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
| 140 | ext4_set_bit(tmp - start, bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 141 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 142 | tmp = ext4_inode_bitmap(sb, gdp); |
| 143 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
| 144 | ext4_set_bit(tmp - start, bh->b_data); |
| 145 | |
| 146 | tmp = ext4_inode_table(sb, gdp); |
| 147 | for (; tmp < ext4_inode_table(sb, gdp) + |
| 148 | sbi->s_itb_per_group; tmp++) { |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 149 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
| 150 | ext4_set_bit(tmp - start, bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 151 | } |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 152 | /* |
| 153 | * Also if the number of blocks within the group is less than |
| 154 | * the blocksize * 8 ( which is the size of bitmap ), set rest |
| 155 | * of the block bitmap to 1 |
| 156 | */ |
| 157 | ext4_mark_bitmap_end(num_blocks_in_group(sb, block_group), |
| 158 | sb->s_blocksize * 8, bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 159 | } |
| 160 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame^] | 161 | /* Return the number of free blocks in a block group. It is used when |
| 162 | * the block bitmap is uninitialized, so we can't just count the bits |
| 163 | * in the bitmap. */ |
| 164 | unsigned ext4_free_blocks_after_init(struct super_block *sb, |
| 165 | ext4_group_t block_group, |
| 166 | struct ext4_group_desc *gdp) |
| 167 | { |
| 168 | return num_blocks_in_group(sb, block_group) - |
| 169 | num_base_meta_blocks(sb, block_group) - |
| 170 | ext4_group_used_meta_blocks(sb, block_group, gdp); |
| 171 | } |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 172 | |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 173 | /* |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 174 | * The free blocks are managed by bitmaps. A file system contains several |
| 175 | * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap |
| 176 | * block for inodes, N blocks for the inode table and data blocks. |
| 177 | * |
| 178 | * The file system contains group descriptors which are located after the |
| 179 | * super block. Each descriptor contains the number of the bitmap block and |
| 180 | * 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] | 181 | * when a file system is mounted (see ext4_fill_super). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 182 | */ |
| 183 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 184 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 185 | * ext4_get_group_desc() -- load group descriptor from disk |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 186 | * @sb: super block |
| 187 | * @block_group: given block group |
| 188 | * @bh: pointer to the buffer head to store the block |
| 189 | * group descriptor |
| 190 | */ |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 191 | struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 192 | ext4_group_t block_group, |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 193 | struct buffer_head **bh) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 194 | { |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 195 | unsigned int group_desc; |
| 196 | unsigned int offset; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 197 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 198 | struct ext4_group_desc *desc; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 199 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 200 | |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 201 | if (block_group >= ngroups) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 202 | ext4_error(sb, "block_group >= groups_count - block_group = %u," |
| 203 | " groups_count = %u", block_group, ngroups); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 204 | |
| 205 | return NULL; |
| 206 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 207 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 208 | group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); |
| 209 | offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 210 | if (!sbi->s_group_desc[group_desc]) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 211 | ext4_error(sb, "Group descriptor not loaded - " |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 212 | "block_group = %u, group_desc = %u, desc = %u", |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 213 | block_group, group_desc, offset); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 214 | return NULL; |
| 215 | } |
| 216 | |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 217 | desc = (struct ext4_group_desc *)( |
| 218 | (__u8 *)sbi->s_group_desc[group_desc]->b_data + |
| 219 | offset * EXT4_DESC_SIZE(sb)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 220 | if (bh) |
| 221 | *bh = sbi->s_group_desc[group_desc]; |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 222 | return desc; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 223 | } |
| 224 | |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 225 | static int ext4_valid_block_bitmap(struct super_block *sb, |
| 226 | struct ext4_group_desc *desc, |
| 227 | unsigned int block_group, |
| 228 | struct buffer_head *bh) |
| 229 | { |
| 230 | ext4_grpblk_t offset; |
| 231 | ext4_grpblk_t next_zero_bit; |
| 232 | ext4_fsblk_t bitmap_blk; |
| 233 | ext4_fsblk_t group_first_block; |
| 234 | |
| 235 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { |
| 236 | /* with FLEX_BG, the inode/block bitmaps and itable |
| 237 | * blocks may not be in the group at all |
| 238 | * so the bitmap validation will be skipped for those groups |
| 239 | * or it has to also read the block group where the bitmaps |
| 240 | * are located to verify they are set. |
| 241 | */ |
| 242 | return 1; |
| 243 | } |
| 244 | group_first_block = ext4_group_first_block_no(sb, block_group); |
| 245 | |
| 246 | /* check whether block bitmap block number is set */ |
| 247 | bitmap_blk = ext4_block_bitmap(sb, desc); |
| 248 | offset = bitmap_blk - group_first_block; |
| 249 | if (!ext4_test_bit(offset, bh->b_data)) |
| 250 | /* bad block bitmap */ |
| 251 | goto err_out; |
| 252 | |
| 253 | /* check whether the inode bitmap block number is set */ |
| 254 | bitmap_blk = ext4_inode_bitmap(sb, desc); |
| 255 | offset = bitmap_blk - group_first_block; |
| 256 | if (!ext4_test_bit(offset, bh->b_data)) |
| 257 | /* bad block bitmap */ |
| 258 | goto err_out; |
| 259 | |
| 260 | /* check whether the inode table block number is set */ |
| 261 | bitmap_blk = ext4_inode_table(sb, desc); |
| 262 | offset = bitmap_blk - group_first_block; |
| 263 | next_zero_bit = ext4_find_next_zero_bit(bh->b_data, |
| 264 | offset + EXT4_SB(sb)->s_itb_per_group, |
| 265 | offset); |
| 266 | if (next_zero_bit >= offset + EXT4_SB(sb)->s_itb_per_group) |
| 267 | /* good bitmap for inode tables */ |
| 268 | return 1; |
| 269 | |
| 270 | err_out: |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 271 | 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] | 272 | block_group, bitmap_blk); |
| 273 | return 0; |
| 274 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 275 | /** |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 276 | * ext4_read_block_bitmap() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 277 | * @sb: super block |
| 278 | * @block_group: given block group |
| 279 | * |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 280 | * Read the bitmap for a given block_group,and validate the |
| 281 | * bits for block/inode/inode tables are set in the bitmaps |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 282 | * |
| 283 | * Return buffer_head on success or NULL in case of failure. |
| 284 | */ |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 285 | struct buffer_head * |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 286 | 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] | 287 | { |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 288 | struct ext4_group_desc *desc; |
| 289 | struct buffer_head *bh = NULL; |
Aneesh Kumar K.V | 7c9e69f | 2007-10-16 23:27:02 -0700 | [diff] [blame] | 290 | ext4_fsblk_t bitmap_blk; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 291 | |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 292 | desc = ext4_get_group_desc(sb, block_group, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 293 | if (!desc) |
Aneesh Kumar K.V | 7c9e69f | 2007-10-16 23:27:02 -0700 | [diff] [blame] | 294 | return NULL; |
| 295 | bitmap_blk = ext4_block_bitmap(sb, desc); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 296 | bh = sb_getblk(sb, bitmap_blk); |
| 297 | if (unlikely(!bh)) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 298 | ext4_error(sb, "Cannot read block bitmap - " |
Theodore Ts'o | a9df9a4 | 2009-01-05 22:18:16 -0500 | [diff] [blame] | 299 | "block_group = %u, block_bitmap = %llu", |
Eric Sandeen | e29d1cd | 2008-08-02 21:21:02 -0400 | [diff] [blame] | 300 | block_group, bitmap_blk); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 301 | return NULL; |
| 302 | } |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 303 | |
| 304 | if (bitmap_uptodate(bh)) |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 305 | return bh; |
| 306 | |
Frederic Bohe | c806e68 | 2008-10-10 08:09:18 -0400 | [diff] [blame] | 307 | lock_buffer(bh); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 308 | if (bitmap_uptodate(bh)) { |
| 309 | unlock_buffer(bh); |
| 310 | return bh; |
| 311 | } |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 312 | ext4_lock_group(sb, block_group); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 313 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { |
| 314 | ext4_init_block_bitmap(sb, bh, block_group, desc); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 315 | set_bitmap_uptodate(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 316 | set_buffer_uptodate(bh); |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 317 | ext4_unlock_group(sb, block_group); |
Aneesh Kumar K.V | 3300bed | 2009-01-03 22:33:39 -0500 | [diff] [blame] | 318 | unlock_buffer(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 319 | return bh; |
| 320 | } |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 321 | ext4_unlock_group(sb, block_group); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 322 | if (buffer_uptodate(bh)) { |
| 323 | /* |
| 324 | * if not uninit if bh is uptodate, |
| 325 | * bitmap is also uptodate |
| 326 | */ |
| 327 | set_bitmap_uptodate(bh); |
| 328 | unlock_buffer(bh); |
| 329 | return bh; |
| 330 | } |
| 331 | /* |
| 332 | * submit the buffer_head for read. We can |
| 333 | * safely mark the bitmap as uptodate now. |
| 334 | * We do it here so the bitmap uptodate bit |
| 335 | * get set with buffer lock held. |
| 336 | */ |
Jiaying Zhang | 0562e0b | 2011-03-21 21:38:05 -0400 | [diff] [blame] | 337 | trace_ext4_read_block_bitmap_load(sb, block_group); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 338 | set_bitmap_uptodate(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 339 | if (bh_submit_read(bh) < 0) { |
| 340 | put_bh(bh); |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 341 | ext4_error(sb, "Cannot read block bitmap - " |
Theodore Ts'o | a9df9a4 | 2009-01-05 22:18:16 -0500 | [diff] [blame] | 342 | "block_group = %u, block_bitmap = %llu", |
Eric Sandeen | e29d1cd | 2008-08-02 21:21:02 -0400 | [diff] [blame] | 343 | block_group, bitmap_blk); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 344 | return NULL; |
| 345 | } |
Aneesh Kumar K.V | 519deca0 | 2008-05-15 14:43:20 -0400 | [diff] [blame] | 346 | ext4_valid_block_bitmap(sb, desc, block_group, bh); |
| 347 | /* |
| 348 | * file system mounted not to panic on error, |
| 349 | * continue with corrupt bitmap |
| 350 | */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 351 | return bh; |
| 352 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 353 | |
| 354 | /** |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 355 | * ext4_has_free_blocks() |
| 356 | * @sbi: in-core super block structure. |
| 357 | * @nblocks: number of needed blocks |
| 358 | * |
| 359 | * Check if filesystem has nblocks free & available for allocation. |
| 360 | * On success return 1, return 0 on failure. |
| 361 | */ |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 362 | static int ext4_has_free_blocks(struct ext4_sb_info *sbi, |
| 363 | s64 nblocks, unsigned int flags) |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 364 | { |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 365 | s64 free_blocks, dirty_blocks, root_blocks; |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 366 | struct percpu_counter *fbc = &sbi->s_freeblocks_counter; |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 367 | struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter; |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 368 | |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 369 | free_blocks = percpu_counter_read_positive(fbc); |
| 370 | dirty_blocks = percpu_counter_read_positive(dbc); |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 371 | root_blocks = ext4_r_blocks_count(sbi->s_es); |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 372 | |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 373 | if (free_blocks - (nblocks + root_blocks + dirty_blocks) < |
| 374 | EXT4_FREEBLOCKS_WATERMARK) { |
Andrew Morton | 02d2116 | 2008-12-09 13:14:14 -0800 | [diff] [blame] | 375 | free_blocks = percpu_counter_sum_positive(fbc); |
| 376 | dirty_blocks = percpu_counter_sum_positive(dbc); |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 377 | } |
| 378 | /* Check whether we have space after |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 379 | * accounting for current dirty blocks & root reserved blocks. |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 380 | */ |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 381 | if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks)) |
| 382 | return 1; |
Aneesh Kumar K.V | 5c79161 | 2008-10-08 23:12:24 -0400 | [diff] [blame] | 383 | |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 384 | /* Hm, nope. Are (enough) root reserved blocks available? */ |
David Howells | 4c9c544 | 2008-11-14 10:38:51 +1100 | [diff] [blame] | 385 | if (sbi->s_resuid == current_fsuid() || |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 386 | ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) || |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 387 | capable(CAP_SYS_RESOURCE) || |
| 388 | (flags & EXT4_MB_USE_ROOT_BLOCKS)) { |
| 389 | |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 390 | if (free_blocks >= (nblocks + dirty_blocks)) |
| 391 | return 1; |
| 392 | } |
| 393 | |
| 394 | return 0; |
Aneesh Kumar K.V | a30d542a | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 395 | } |
Mingming Cao | 0703143 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 396 | |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 397 | int ext4_claim_free_blocks(struct ext4_sb_info *sbi, |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 398 | s64 nblocks, unsigned int flags) |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 399 | { |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 400 | if (ext4_has_free_blocks(sbi, nblocks, flags)) { |
Eric Sandeen | 8c3bf8a0 | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 401 | percpu_counter_add(&sbi->s_dirtyblocks_counter, nblocks); |
| 402 | return 0; |
| 403 | } else |
| 404 | return -ENOSPC; |
| 405 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 406 | |
| 407 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 408 | * ext4_should_retry_alloc() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 409 | * @sb: super block |
| 410 | * @retries number of attemps has been made |
| 411 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 412 | * ext4_should_retry_alloc() is called when ENOSPC is returned, and if |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 413 | * it is profitable to retry the operation, this function will wait |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 414 | * for the current or committing transaction to complete, and then |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 415 | * return TRUE. |
| 416 | * |
| 417 | * if the total number of retries exceed three times, return FALSE. |
| 418 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 419 | int ext4_should_retry_alloc(struct super_block *sb, int *retries) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 420 | { |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 421 | if (!ext4_has_free_blocks(EXT4_SB(sb), 1, 0) || |
Eric Sandeen | 8f64b32 | 2009-02-26 00:57:35 -0500 | [diff] [blame] | 422 | (*retries)++ > 3 || |
| 423 | !EXT4_SB(sb)->s_journal) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 424 | return 0; |
| 425 | |
| 426 | jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id); |
| 427 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 428 | return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 429 | } |
| 430 | |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 431 | /* |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 432 | * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks |
| 433 | * |
| 434 | * @handle: handle to this transaction |
| 435 | * @inode: file inode |
| 436 | * @goal: given target block(filesystem wide) |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 437 | * @count: pointer to total number of blocks needed |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 438 | * @errp: error code |
| 439 | * |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 440 | * 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] | 441 | * error stores in errp pointer |
| 442 | */ |
| 443 | 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] | 444 | ext4_fsblk_t goal, unsigned int flags, |
| 445 | unsigned long *count, int *errp) |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 446 | { |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 447 | struct ext4_allocation_request ar; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 448 | ext4_fsblk_t ret; |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 449 | |
| 450 | memset(&ar, 0, sizeof(ar)); |
| 451 | /* Fill with neighbour allocated blocks */ |
| 452 | ar.inode = inode; |
| 453 | ar.goal = goal; |
| 454 | ar.len = count ? *count : 1; |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 455 | ar.flags = flags; |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 456 | |
| 457 | ret = ext4_mb_new_blocks(handle, &ar, errp); |
| 458 | if (count) |
| 459 | *count = ar.len; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 460 | /* |
Eric Sandeen | 72b8ab9 | 2010-05-16 11:00:00 -0400 | [diff] [blame] | 461 | * Account for the allocated meta blocks. We will never |
| 462 | * fail EDQUOT for metdata, but we do account for it. |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 463 | */ |
Theodore Ts'o | f232109 | 2011-01-10 12:12:36 -0500 | [diff] [blame] | 464 | if (!(*errp) && |
| 465 | ext4_test_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED)) { |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 466 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 467 | EXT4_I(inode)->i_allocated_meta_blocks += ar.len; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 468 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
Eric Sandeen | 72b8ab9 | 2010-05-16 11:00:00 -0400 | [diff] [blame] | 469 | dquot_alloc_block_nofail(inode, ar.len); |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 470 | } |
| 471 | return ret; |
| 472 | } |
| 473 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 474 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 475 | * ext4_count_free_blocks() -- count filesystem free blocks |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 476 | * @sb: superblock |
| 477 | * |
| 478 | * Adds up the number of free blocks from each block group. |
| 479 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 480 | ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 481 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 482 | ext4_fsblk_t desc_count; |
| 483 | struct ext4_group_desc *gdp; |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 484 | ext4_group_t i; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 485 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 486 | #ifdef EXT4FS_DEBUG |
| 487 | struct ext4_super_block *es; |
| 488 | ext4_fsblk_t bitmap_count; |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 489 | unsigned int x; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 490 | struct buffer_head *bitmap_bh = NULL; |
| 491 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 492 | es = EXT4_SB(sb)->s_es; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 493 | desc_count = 0; |
| 494 | bitmap_count = 0; |
| 495 | gdp = NULL; |
| 496 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 497 | for (i = 0; i < ngroups; i++) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 498 | gdp = ext4_get_group_desc(sb, i, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 499 | if (!gdp) |
| 500 | continue; |
Thadeu Lima de Souza Cascardo | 9fd9784 | 2009-01-26 19:26:26 -0500 | [diff] [blame] | 501 | desc_count += ext4_free_blks_count(sb, gdp); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 502 | brelse(bitmap_bh); |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 503 | bitmap_bh = ext4_read_block_bitmap(sb, i); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 504 | if (bitmap_bh == NULL) |
| 505 | continue; |
| 506 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 507 | x = ext4_count_free(bitmap_bh, sb->s_blocksize); |
Thadeu Lima de Souza Cascardo | 9fd9784 | 2009-01-26 19:26:26 -0500 | [diff] [blame] | 508 | printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n", |
| 509 | i, ext4_free_blks_count(sb, gdp), x); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 510 | bitmap_count += x; |
| 511 | } |
| 512 | brelse(bitmap_bh); |
Theodore Ts'o | 4776004f | 2008-09-08 23:00:52 -0400 | [diff] [blame] | 513 | printk(KERN_DEBUG "ext4_count_free_blocks: stored = %llu" |
| 514 | ", computed = %llu, %llu\n", ext4_free_blocks_count(es), |
| 515 | desc_count, bitmap_count); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 516 | return bitmap_count; |
| 517 | #else |
| 518 | desc_count = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 519 | for (i = 0; i < ngroups; i++) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 520 | gdp = ext4_get_group_desc(sb, i, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 521 | if (!gdp) |
| 522 | continue; |
Aneesh Kumar K.V | 560671a | 2009-01-05 22:20:24 -0500 | [diff] [blame] | 523 | desc_count += ext4_free_blks_count(sb, gdp); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 524 | } |
| 525 | |
| 526 | return desc_count; |
| 527 | #endif |
| 528 | } |
| 529 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 530 | static inline int test_root(ext4_group_t a, int b) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 531 | { |
| 532 | int num = b; |
| 533 | |
| 534 | while (a > num) |
| 535 | num *= b; |
| 536 | return num == a; |
| 537 | } |
| 538 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 539 | static int ext4_group_sparse(ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 540 | { |
| 541 | if (group <= 1) |
| 542 | return 1; |
| 543 | if (!(group & 1)) |
| 544 | return 0; |
| 545 | return (test_root(group, 7) || test_root(group, 5) || |
| 546 | test_root(group, 3)); |
| 547 | } |
| 548 | |
| 549 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 550 | * 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] | 551 | * @sb: superblock for filesystem |
| 552 | * @group: group number to check |
| 553 | * |
| 554 | * Return the number of blocks used by the superblock (primary or backup) |
| 555 | * in this group. Currently this will be only 0 or 1. |
| 556 | */ |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 557 | 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] | 558 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 559 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, |
| 560 | EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) && |
| 561 | !ext4_group_sparse(group)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 562 | return 0; |
| 563 | return 1; |
| 564 | } |
| 565 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 566 | static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, |
| 567 | 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 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 570 | ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb); |
| 571 | ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 572 | |
| 573 | if (group == first || group == first + 1 || group == last) |
| 574 | return 1; |
| 575 | return 0; |
| 576 | } |
| 577 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 578 | static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, |
| 579 | ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 580 | { |
Theodore Ts'o | 8dadb19 | 2009-11-23 07:24:38 -0500 | [diff] [blame] | 581 | if (!ext4_bg_has_super(sb, group)) |
| 582 | return 0; |
| 583 | |
| 584 | if (EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG)) |
| 585 | return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
| 586 | else |
| 587 | return EXT4_SB(sb)->s_gdb_count; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 588 | } |
| 589 | |
| 590 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 591 | * 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] | 592 | * @sb: superblock for filesystem |
| 593 | * @group: group number to check |
| 594 | * |
| 595 | * Return the number of blocks used by the group descriptor table |
| 596 | * (primary or backup) in this group. In the future there may be a |
| 597 | * different number of descriptor blocks in each group. |
| 598 | */ |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 599 | 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] | 600 | { |
| 601 | unsigned long first_meta_bg = |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 602 | le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
| 603 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 604 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 605 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) || |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 606 | metagroup < first_meta_bg) |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 607 | return ext4_bg_num_gdb_nometa(sb, group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 608 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 609 | return ext4_bg_num_gdb_meta(sb,group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 610 | |
| 611 | } |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 612 | |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 613 | /* |
| 614 | * This function returns the number of file system metadata blocks at |
| 615 | * the beginning of a block group, including the reserved gdt blocks. |
| 616 | */ |
| 617 | static unsigned int num_base_meta_blocks(struct super_block *sb, |
| 618 | ext4_group_t block_group) |
| 619 | { |
| 620 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 621 | int num; |
| 622 | |
| 623 | /* Check for superblock and gdt backups in this group */ |
| 624 | num = ext4_bg_has_super(sb, block_group); |
| 625 | |
| 626 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) || |
| 627 | block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) * |
| 628 | sbi->s_desc_per_block) { |
| 629 | if (num) { |
| 630 | num += ext4_bg_num_gdb(sb, block_group); |
| 631 | num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks); |
| 632 | } |
| 633 | } else { /* For META_BG_BLOCK_GROUPS */ |
| 634 | num += ext4_bg_num_gdb(sb, block_group); |
| 635 | } |
| 636 | return num; |
| 637 | } |
Eric Sandeen | f86186b | 2011-06-28 10:01:31 -0400 | [diff] [blame] | 638 | /** |
| 639 | * ext4_inode_to_goal_block - return a hint for block allocation |
| 640 | * @inode: inode for block allocation |
| 641 | * |
| 642 | * Return the ideal location to start allocating blocks for a |
| 643 | * newly created inode. |
| 644 | */ |
| 645 | ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode) |
| 646 | { |
| 647 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 648 | ext4_group_t block_group; |
| 649 | ext4_grpblk_t colour; |
| 650 | int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); |
| 651 | ext4_fsblk_t bg_start; |
| 652 | ext4_fsblk_t last_block; |
| 653 | |
| 654 | block_group = ei->i_block_group; |
| 655 | if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { |
| 656 | /* |
| 657 | * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME |
| 658 | * block groups per flexgroup, reserve the first block |
| 659 | * group for directories and special files. Regular |
| 660 | * files will start at the second block group. This |
| 661 | * tends to speed up directory access and improves |
| 662 | * fsck times. |
| 663 | */ |
| 664 | block_group &= ~(flex_size-1); |
| 665 | if (S_ISREG(inode->i_mode)) |
| 666 | block_group++; |
| 667 | } |
| 668 | bg_start = ext4_group_first_block_no(inode->i_sb, block_group); |
| 669 | last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; |
| 670 | |
| 671 | /* |
| 672 | * If we are doing delayed allocation, we don't need take |
| 673 | * colour into account. |
| 674 | */ |
| 675 | if (test_opt(inode->i_sb, DELALLOC)) |
| 676 | return bg_start; |
| 677 | |
| 678 | if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) |
| 679 | colour = (current->pid % 16) * |
| 680 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
| 681 | else |
| 682 | colour = (current->pid % 16) * ((last_block - bg_start) / 16); |
| 683 | return bg_start + colour; |
| 684 | } |
| 685 | |