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 | /* |
Theodore Ts'o | 3212a80 | 2011-09-09 18:46:51 -0400 | [diff] [blame] | 31 | * Calculate the block group number and offset into the block/cluster |
| 32 | * allocation bitmap, given a block number |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 33 | */ |
| 34 | 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] | 35 | ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp) |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 36 | { |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 37 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 38 | ext4_grpblk_t offset; |
| 39 | |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 40 | blocknr = blocknr - le32_to_cpu(es->s_first_data_block); |
Theodore Ts'o | 3212a80 | 2011-09-09 18:46:51 -0400 | [diff] [blame] | 41 | offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)) >> |
| 42 | EXT4_SB(sb)->s_cluster_bits; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 43 | if (offsetp) |
| 44 | *offsetp = offset; |
| 45 | if (blockgrpp) |
Dave Kleikamp | 8c55e20 | 2007-05-24 13:04:54 -0400 | [diff] [blame] | 46 | *blockgrpp = blocknr; |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 47 | |
| 48 | } |
| 49 | |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 50 | static int ext4_block_in_group(struct super_block *sb, ext4_fsblk_t block, |
| 51 | ext4_group_t block_group) |
| 52 | { |
| 53 | ext4_group_t actual_group; |
Aneesh Kumar K.V | 7477827 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 54 | ext4_get_group_no_and_offset(sb, block, &actual_group, NULL); |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 55 | if (actual_group == block_group) |
| 56 | return 1; |
| 57 | return 0; |
| 58 | } |
| 59 | |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 60 | /* Return the number of clusters used for file system metadata; this |
| 61 | * represents the overhead needed by the file system. |
| 62 | */ |
| 63 | unsigned ext4_num_overhead_clusters(struct super_block *sb, |
| 64 | ext4_group_t block_group, |
| 65 | struct ext4_group_desc *gdp) |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 66 | { |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 67 | unsigned num_clusters; |
| 68 | int block_cluster = -1, inode_cluster = -1, itbl_cluster = -1, i, c; |
| 69 | ext4_fsblk_t start = ext4_group_first_block_no(sb, block_group); |
| 70 | ext4_fsblk_t itbl_blk; |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 71 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 72 | |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 73 | /* This is the number of clusters used by the superblock, |
| 74 | * block group descriptors, and reserved block group |
| 75 | * descriptor blocks */ |
| 76 | num_clusters = ext4_num_base_meta_clusters(sb, block_group); |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 77 | |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 78 | /* |
| 79 | * For the allocation bitmaps and inode table, we first need |
| 80 | * to check to see if the block is in the block group. If it |
| 81 | * is, then check to see if the cluster is already accounted |
| 82 | * for in the clusters used for the base metadata cluster, or |
| 83 | * if we can increment the base metadata cluster to include |
| 84 | * that block. Otherwise, we will have to track the cluster |
| 85 | * used for the allocation bitmap or inode table explicitly. |
| 86 | * Normally all of these blocks are contiguous, so the special |
| 87 | * case handling shouldn't be necessary except for *very* |
| 88 | * unusual file system layouts. |
| 89 | */ |
| 90 | if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) { |
| 91 | block_cluster = EXT4_B2C(sbi, (start - |
| 92 | ext4_block_bitmap(sb, gdp))); |
| 93 | if (block_cluster < num_clusters) |
| 94 | block_cluster = -1; |
| 95 | else if (block_cluster == num_clusters) { |
| 96 | num_clusters++; |
| 97 | block_cluster = -1; |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 98 | } |
| 99 | } |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 100 | |
| 101 | if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) { |
| 102 | inode_cluster = EXT4_B2C(sbi, |
| 103 | start - ext4_inode_bitmap(sb, gdp)); |
| 104 | if (inode_cluster < num_clusters) |
| 105 | inode_cluster = -1; |
| 106 | else if (inode_cluster == num_clusters) { |
| 107 | num_clusters++; |
| 108 | inode_cluster = -1; |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | itbl_blk = ext4_inode_table(sb, gdp); |
| 113 | for (i = 0; i < sbi->s_itb_per_group; i++) { |
| 114 | if (ext4_block_in_group(sb, itbl_blk + i, block_group)) { |
| 115 | c = EXT4_B2C(sbi, start - itbl_blk + i); |
| 116 | if ((c < num_clusters) || (c == inode_cluster) || |
| 117 | (c == block_cluster) || (c == itbl_cluster)) |
| 118 | continue; |
| 119 | if (c == num_clusters) { |
| 120 | num_clusters++; |
| 121 | continue; |
| 122 | } |
| 123 | num_clusters++; |
| 124 | itbl_cluster = c; |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | if (block_cluster != -1) |
| 129 | num_clusters++; |
| 130 | if (inode_cluster != -1) |
| 131 | num_clusters++; |
| 132 | |
| 133 | return num_clusters; |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 134 | } |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 135 | |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 136 | static unsigned int num_clusters_in_group(struct super_block *sb, |
| 137 | ext4_group_t block_group) |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 138 | { |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 139 | unsigned int blocks; |
| 140 | |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 141 | if (block_group == ext4_get_groups_count(sb) - 1) { |
| 142 | /* |
| 143 | * Even though mke2fs always initializes the first and |
| 144 | * last group, just in case some other tool was used, |
| 145 | * we need to make sure we calculate the right free |
| 146 | * blocks. |
| 147 | */ |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 148 | blocks = ext4_blocks_count(EXT4_SB(sb)->s_es) - |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 149 | ext4_group_first_block_no(sb, block_group); |
| 150 | } else |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 151 | blocks = EXT4_BLOCKS_PER_GROUP(sb); |
| 152 | return EXT4_NUM_B2C(EXT4_SB(sb), blocks); |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 153 | } |
| 154 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 155 | /* Initializes an uninitialized block bitmap */ |
| 156 | void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, |
| 157 | ext4_group_t block_group, |
| 158 | struct ext4_group_desc *gdp) |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 159 | { |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 160 | unsigned int bit, bit_max; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 161 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 162 | ext4_fsblk_t start, tmp; |
| 163 | int flex_bg = 0; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 164 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 165 | J_ASSERT_BH(bh, buffer_locked(bh)); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 166 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 167 | /* If checksum is bad mark all blocks used to prevent allocation |
| 168 | * essentially implementing a per-group read-only flag. */ |
| 169 | if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { |
| 170 | ext4_error(sb, "Checksum bad for group %u", block_group); |
Theodore Ts'o | 021b65b | 2011-09-09 19:08:51 -0400 | [diff] [blame] | 171 | ext4_free_group_clusters_set(sb, gdp, 0); |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 172 | ext4_free_inodes_set(sb, gdp, 0); |
| 173 | ext4_itable_unused_set(sb, gdp, 0); |
| 174 | memset(bh->b_data, 0xff, sb->s_blocksize); |
| 175 | return; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 176 | } |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 177 | memset(bh->b_data, 0, sb->s_blocksize); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 178 | |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 179 | bit_max = ext4_num_base_meta_clusters(sb, block_group); |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 180 | for (bit = 0; bit < bit_max; bit++) |
| 181 | ext4_set_bit(bit, bh->b_data); |
Akinobu Mita | d00a6d7 | 2008-04-17 10:38:59 -0400 | [diff] [blame] | 182 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 183 | start = ext4_group_first_block_no(sb, block_group); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 184 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 185 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) |
| 186 | flex_bg = 1; |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 187 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 188 | /* Set bits for block and inode bitmaps, and inode table */ |
| 189 | tmp = ext4_block_bitmap(sb, gdp); |
| 190 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 191 | ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 192 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 193 | tmp = ext4_inode_bitmap(sb, gdp); |
| 194 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 195 | ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 196 | |
| 197 | tmp = ext4_inode_table(sb, gdp); |
| 198 | for (; tmp < ext4_inode_table(sb, gdp) + |
| 199 | sbi->s_itb_per_group; tmp++) { |
Jose R. Santos | 0bf7e83 | 2008-06-03 14:07:29 -0400 | [diff] [blame] | 200 | if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 201 | ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 202 | } |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 203 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 204 | /* |
| 205 | * Also if the number of blocks within the group is less than |
| 206 | * the blocksize * 8 ( which is the size of bitmap ), set rest |
| 207 | * of the block bitmap to 1 |
| 208 | */ |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 209 | ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group), |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 210 | sb->s_blocksize * 8, bh->b_data); |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 211 | } |
| 212 | |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 213 | /* Return the number of free blocks in a block group. It is used when |
| 214 | * the block bitmap is uninitialized, so we can't just count the bits |
| 215 | * in the bitmap. */ |
| 216 | unsigned ext4_free_blocks_after_init(struct super_block *sb, |
| 217 | ext4_group_t block_group, |
| 218 | struct ext4_group_desc *gdp) |
| 219 | { |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 220 | return num_clusters_in_group(sb, block_group) - |
| 221 | ext4_num_overhead_clusters(sb, block_group, gdp); |
Theodore Ts'o | fd034a8 | 2011-09-09 18:42:51 -0400 | [diff] [blame] | 222 | } |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 223 | |
Andrew Morton | 72b64b5 | 2006-10-11 01:21:18 -0700 | [diff] [blame] | 224 | /* |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 225 | * The free blocks are managed by bitmaps. A file system contains several |
| 226 | * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap |
| 227 | * block for inodes, N blocks for the inode table and data blocks. |
| 228 | * |
| 229 | * The file system contains group descriptors which are located after the |
| 230 | * super block. Each descriptor contains the number of the bitmap block and |
| 231 | * 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] | 232 | * when a file system is mounted (see ext4_fill_super). |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 233 | */ |
| 234 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 235 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 236 | * ext4_get_group_desc() -- load group descriptor from disk |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 237 | * @sb: super block |
| 238 | * @block_group: given block group |
| 239 | * @bh: pointer to the buffer head to store the block |
| 240 | * group descriptor |
| 241 | */ |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 242 | struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 243 | ext4_group_t block_group, |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 244 | struct buffer_head **bh) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 245 | { |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 246 | unsigned int group_desc; |
| 247 | unsigned int offset; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 248 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 249 | struct ext4_group_desc *desc; |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 250 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 251 | |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 252 | if (block_group >= ngroups) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 253 | ext4_error(sb, "block_group >= groups_count - block_group = %u," |
| 254 | " groups_count = %u", block_group, ngroups); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 255 | |
| 256 | return NULL; |
| 257 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 258 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 259 | group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); |
| 260 | offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 261 | if (!sbi->s_group_desc[group_desc]) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 262 | ext4_error(sb, "Group descriptor not loaded - " |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 263 | "block_group = %u, group_desc = %u, desc = %u", |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 264 | block_group, group_desc, offset); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 265 | return NULL; |
| 266 | } |
| 267 | |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 268 | desc = (struct ext4_group_desc *)( |
| 269 | (__u8 *)sbi->s_group_desc[group_desc]->b_data + |
| 270 | offset * EXT4_DESC_SIZE(sb)); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 271 | if (bh) |
| 272 | *bh = sbi->s_group_desc[group_desc]; |
Alexandre Ratchov | 0d1ee42 | 2006-10-11 01:21:14 -0700 | [diff] [blame] | 273 | return desc; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 274 | } |
| 275 | |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 276 | static int ext4_valid_block_bitmap(struct super_block *sb, |
| 277 | struct ext4_group_desc *desc, |
| 278 | unsigned int block_group, |
| 279 | struct buffer_head *bh) |
| 280 | { |
| 281 | ext4_grpblk_t offset; |
| 282 | ext4_grpblk_t next_zero_bit; |
| 283 | ext4_fsblk_t bitmap_blk; |
| 284 | ext4_fsblk_t group_first_block; |
| 285 | |
| 286 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { |
| 287 | /* with FLEX_BG, the inode/block bitmaps and itable |
| 288 | * blocks may not be in the group at all |
| 289 | * so the bitmap validation will be skipped for those groups |
| 290 | * or it has to also read the block group where the bitmaps |
| 291 | * are located to verify they are set. |
| 292 | */ |
| 293 | return 1; |
| 294 | } |
| 295 | group_first_block = ext4_group_first_block_no(sb, block_group); |
| 296 | |
| 297 | /* check whether block bitmap block number is set */ |
| 298 | bitmap_blk = ext4_block_bitmap(sb, desc); |
| 299 | offset = bitmap_blk - group_first_block; |
| 300 | if (!ext4_test_bit(offset, bh->b_data)) |
| 301 | /* bad block bitmap */ |
| 302 | goto err_out; |
| 303 | |
| 304 | /* check whether the inode bitmap block number is set */ |
| 305 | bitmap_blk = ext4_inode_bitmap(sb, desc); |
| 306 | offset = bitmap_blk - group_first_block; |
| 307 | if (!ext4_test_bit(offset, bh->b_data)) |
| 308 | /* bad block bitmap */ |
| 309 | goto err_out; |
| 310 | |
| 311 | /* check whether the inode table block number is set */ |
| 312 | bitmap_blk = ext4_inode_table(sb, desc); |
| 313 | offset = bitmap_blk - group_first_block; |
| 314 | next_zero_bit = ext4_find_next_zero_bit(bh->b_data, |
| 315 | offset + EXT4_SB(sb)->s_itb_per_group, |
| 316 | offset); |
| 317 | if (next_zero_bit >= offset + EXT4_SB(sb)->s_itb_per_group) |
| 318 | /* good bitmap for inode tables */ |
| 319 | return 1; |
| 320 | |
| 321 | err_out: |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 322 | 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] | 323 | block_group, bitmap_blk); |
| 324 | return 0; |
| 325 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 326 | /** |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 327 | * ext4_read_block_bitmap() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 328 | * @sb: super block |
| 329 | * @block_group: given block group |
| 330 | * |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 331 | * Read the bitmap for a given block_group,and validate the |
| 332 | * bits for block/inode/inode tables are set in the bitmaps |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 333 | * |
| 334 | * Return buffer_head on success or NULL in case of failure. |
| 335 | */ |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 336 | struct buffer_head * |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 337 | 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] | 338 | { |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 339 | struct ext4_group_desc *desc; |
| 340 | struct buffer_head *bh = NULL; |
Aneesh Kumar K.V | 7c9e69f | 2007-10-16 23:27:02 -0700 | [diff] [blame] | 341 | ext4_fsblk_t bitmap_blk; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 342 | |
Andreas Dilger | 717d50e | 2007-10-16 18:38:25 -0400 | [diff] [blame] | 343 | desc = ext4_get_group_desc(sb, block_group, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 344 | if (!desc) |
Aneesh Kumar K.V | 7c9e69f | 2007-10-16 23:27:02 -0700 | [diff] [blame] | 345 | return NULL; |
| 346 | bitmap_blk = ext4_block_bitmap(sb, desc); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 347 | bh = sb_getblk(sb, bitmap_blk); |
| 348 | if (unlikely(!bh)) { |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 349 | ext4_error(sb, "Cannot read block bitmap - " |
Theodore Ts'o | a9df9a4 | 2009-01-05 22:18:16 -0500 | [diff] [blame] | 350 | "block_group = %u, block_bitmap = %llu", |
Eric Sandeen | e29d1cd | 2008-08-02 21:21:02 -0400 | [diff] [blame] | 351 | block_group, bitmap_blk); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 352 | return NULL; |
| 353 | } |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 354 | |
| 355 | if (bitmap_uptodate(bh)) |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 356 | return bh; |
| 357 | |
Frederic Bohe | c806e68 | 2008-10-10 08:09:18 -0400 | [diff] [blame] | 358 | lock_buffer(bh); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 359 | if (bitmap_uptodate(bh)) { |
| 360 | unlock_buffer(bh); |
| 361 | return bh; |
| 362 | } |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 363 | ext4_lock_group(sb, block_group); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 364 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { |
| 365 | ext4_init_block_bitmap(sb, bh, block_group, desc); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 366 | set_bitmap_uptodate(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 367 | set_buffer_uptodate(bh); |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 368 | ext4_unlock_group(sb, block_group); |
Aneesh Kumar K.V | 3300bed | 2009-01-03 22:33:39 -0500 | [diff] [blame] | 369 | unlock_buffer(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 370 | return bh; |
| 371 | } |
Aneesh Kumar K.V | 955ce5f | 2009-05-02 20:35:09 -0400 | [diff] [blame] | 372 | ext4_unlock_group(sb, block_group); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 373 | if (buffer_uptodate(bh)) { |
| 374 | /* |
| 375 | * if not uninit if bh is uptodate, |
| 376 | * bitmap is also uptodate |
| 377 | */ |
| 378 | set_bitmap_uptodate(bh); |
| 379 | unlock_buffer(bh); |
| 380 | return bh; |
| 381 | } |
| 382 | /* |
| 383 | * submit the buffer_head for read. We can |
| 384 | * safely mark the bitmap as uptodate now. |
| 385 | * We do it here so the bitmap uptodate bit |
| 386 | * get set with buffer lock held. |
| 387 | */ |
Jiaying Zhang | 0562e0b | 2011-03-21 21:38:05 -0400 | [diff] [blame] | 388 | trace_ext4_read_block_bitmap_load(sb, block_group); |
Aneesh Kumar K.V | 2ccb5fb | 2009-01-05 21:49:55 -0500 | [diff] [blame] | 389 | set_bitmap_uptodate(bh); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 390 | if (bh_submit_read(bh) < 0) { |
| 391 | put_bh(bh); |
Eric Sandeen | 12062dd | 2010-02-15 14:19:27 -0500 | [diff] [blame] | 392 | ext4_error(sb, "Cannot read block bitmap - " |
Theodore Ts'o | a9df9a4 | 2009-01-05 22:18:16 -0500 | [diff] [blame] | 393 | "block_group = %u, block_bitmap = %llu", |
Eric Sandeen | e29d1cd | 2008-08-02 21:21:02 -0400 | [diff] [blame] | 394 | block_group, bitmap_blk); |
Aneesh Kumar K.V | abcb294 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 395 | return NULL; |
| 396 | } |
Aneesh Kumar K.V | 519deca | 2008-05-15 14:43:20 -0400 | [diff] [blame] | 397 | ext4_valid_block_bitmap(sb, desc, block_group, bh); |
| 398 | /* |
| 399 | * file system mounted not to panic on error, |
| 400 | * continue with corrupt bitmap |
| 401 | */ |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 402 | return bh; |
| 403 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 404 | |
| 405 | /** |
Eric Sandeen | 8c3bf8a | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 406 | * ext4_has_free_blocks() |
| 407 | * @sbi: in-core super block structure. |
| 408 | * @nblocks: number of needed blocks |
| 409 | * |
| 410 | * Check if filesystem has nblocks free & available for allocation. |
| 411 | * On success return 1, return 0 on failure. |
| 412 | */ |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 413 | static int ext4_has_free_blocks(struct ext4_sb_info *sbi, |
| 414 | s64 nblocks, unsigned int flags) |
Aneesh Kumar K.V | a30d542 | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 415 | { |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 416 | s64 free_blocks, dirty_blocks, root_blocks; |
Theodore Ts'o | 5704265 | 2011-09-09 18:56:51 -0400 | [diff] [blame] | 417 | struct percpu_counter *fcc = &sbi->s_freeclusters_counter; |
| 418 | struct percpu_counter *dbc = &sbi->s_dirtyclusters_counter; |
Aneesh Kumar K.V | a30d542 | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 419 | |
Theodore Ts'o | 5704265 | 2011-09-09 18:56:51 -0400 | [diff] [blame] | 420 | free_blocks = percpu_counter_read_positive(fcc); |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 421 | dirty_blocks = percpu_counter_read_positive(dbc); |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 422 | root_blocks = ext4_r_blocks_count(sbi->s_es); |
Aneesh Kumar K.V | a30d542 | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 423 | |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 424 | if (free_blocks - (nblocks + root_blocks + dirty_blocks) < |
| 425 | EXT4_FREEBLOCKS_WATERMARK) { |
Theodore Ts'o | 5704265 | 2011-09-09 18:56:51 -0400 | [diff] [blame] | 426 | free_blocks = EXT4_C2B(sbi, percpu_counter_sum_positive(fcc)); |
Andrew Morton | 02d2116 | 2008-12-09 13:14:14 -0800 | [diff] [blame] | 427 | dirty_blocks = percpu_counter_sum_positive(dbc); |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 428 | } |
| 429 | /* Check whether we have space after |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 430 | * accounting for current dirty blocks & root reserved blocks. |
Aneesh Kumar K.V | 6bc6e63 | 2008-10-10 09:39:00 -0400 | [diff] [blame] | 431 | */ |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 432 | if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks)) |
| 433 | return 1; |
Aneesh Kumar K.V | 5c79161 | 2008-10-08 23:12:24 -0400 | [diff] [blame] | 434 | |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 435 | /* Hm, nope. Are (enough) root reserved blocks available? */ |
David Howells | 4c9c544 | 2008-11-14 10:38:51 +1100 | [diff] [blame] | 436 | if (sbi->s_resuid == current_fsuid() || |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 437 | ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) || |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 438 | capable(CAP_SYS_RESOURCE) || |
| 439 | (flags & EXT4_MB_USE_ROOT_BLOCKS)) { |
| 440 | |
Eric Sandeen | a996031 | 2008-10-28 00:08:17 -0400 | [diff] [blame] | 441 | if (free_blocks >= (nblocks + dirty_blocks)) |
| 442 | return 1; |
| 443 | } |
| 444 | |
| 445 | return 0; |
Aneesh Kumar K.V | a30d542 | 2008-10-09 10:56:23 -0400 | [diff] [blame] | 446 | } |
Mingming Cao | 0703143 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 447 | |
Eric Sandeen | 8c3bf8a | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 448 | int ext4_claim_free_blocks(struct ext4_sb_info *sbi, |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 449 | s64 nblocks, unsigned int flags) |
Eric Sandeen | 8c3bf8a | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 450 | { |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 451 | if (ext4_has_free_blocks(sbi, nblocks, flags)) { |
Theodore Ts'o | 5704265 | 2011-09-09 18:56:51 -0400 | [diff] [blame] | 452 | percpu_counter_add(&sbi->s_dirtyclusters_counter, nblocks); |
Eric Sandeen | 8c3bf8a | 2008-10-28 00:08:12 -0400 | [diff] [blame] | 453 | return 0; |
| 454 | } else |
| 455 | return -ENOSPC; |
| 456 | } |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 457 | |
| 458 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 459 | * ext4_should_retry_alloc() |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 460 | * @sb: super block |
| 461 | * @retries number of attemps has been made |
| 462 | * |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 463 | * ext4_should_retry_alloc() is called when ENOSPC is returned, and if |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 464 | * it is profitable to retry the operation, this function will wait |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 465 | * for the current or committing transaction to complete, and then |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 466 | * return TRUE. |
| 467 | * |
| 468 | * if the total number of retries exceed three times, return FALSE. |
| 469 | */ |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 470 | int ext4_should_retry_alloc(struct super_block *sb, int *retries) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 471 | { |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 472 | if (!ext4_has_free_blocks(EXT4_SB(sb), 1, 0) || |
Eric Sandeen | 8f64b32 | 2009-02-26 00:57:35 -0500 | [diff] [blame] | 473 | (*retries)++ > 3 || |
| 474 | !EXT4_SB(sb)->s_journal) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 475 | return 0; |
| 476 | |
| 477 | jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id); |
| 478 | |
Mingming Cao | dab291a | 2006-10-11 01:21:01 -0700 | [diff] [blame] | 479 | return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 480 | } |
| 481 | |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 482 | /* |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 483 | * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks |
| 484 | * |
| 485 | * @handle: handle to this transaction |
| 486 | * @inode: file inode |
| 487 | * @goal: given target block(filesystem wide) |
Aditya Kali | 7b415bf | 2011-09-09 19:04:51 -0400 | [diff] [blame] | 488 | * @count: pointer to total number of clusters needed |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 489 | * @errp: error code |
| 490 | * |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 491 | * 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] | 492 | * error stores in errp pointer |
| 493 | */ |
| 494 | 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] | 495 | ext4_fsblk_t goal, unsigned int flags, |
| 496 | unsigned long *count, int *errp) |
Aneesh Kumar K.V | 654b490 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 497 | { |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 498 | struct ext4_allocation_request ar; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 499 | ext4_fsblk_t ret; |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 500 | |
| 501 | memset(&ar, 0, sizeof(ar)); |
| 502 | /* Fill with neighbour allocated blocks */ |
| 503 | ar.inode = inode; |
| 504 | ar.goal = goal; |
| 505 | ar.len = count ? *count : 1; |
Allison Henderson | 55f020d | 2011-05-25 07:41:26 -0400 | [diff] [blame] | 506 | ar.flags = flags; |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 507 | |
| 508 | ret = ext4_mb_new_blocks(handle, &ar, errp); |
| 509 | if (count) |
| 510 | *count = ar.len; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 511 | /* |
Eric Sandeen | 72b8ab9 | 2010-05-16 11:00:00 -0400 | [diff] [blame] | 512 | * Account for the allocated meta blocks. We will never |
| 513 | * fail EDQUOT for metdata, but we do account for it. |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 514 | */ |
Theodore Ts'o | f232109 | 2011-01-10 12:12:36 -0500 | [diff] [blame] | 515 | if (!(*errp) && |
| 516 | ext4_test_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED)) { |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 517 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
Theodore Ts'o | 97df5d1 | 2008-12-12 12:41:28 -0500 | [diff] [blame] | 518 | EXT4_I(inode)->i_allocated_meta_blocks += ar.len; |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 519 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
Aditya Kali | 7b415bf | 2011-09-09 19:04:51 -0400 | [diff] [blame] | 520 | dquot_alloc_block_nofail(inode, |
| 521 | EXT4_C2B(EXT4_SB(inode->i_sb), ar.len)); |
Mingming Cao | d2a1763 | 2008-07-14 17:52:37 -0400 | [diff] [blame] | 522 | } |
| 523 | return ret; |
| 524 | } |
| 525 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 526 | /** |
Theodore Ts'o | 5dee543 | 2011-09-09 19:10:51 -0400 | [diff] [blame^] | 527 | * ext4_count_free_clusters() -- count filesystem free clusters |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 528 | * @sb: superblock |
| 529 | * |
Theodore Ts'o | 5dee543 | 2011-09-09 19:10:51 -0400 | [diff] [blame^] | 530 | * Adds up the number of free clusters from each block group. |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 531 | */ |
Theodore Ts'o | 5dee543 | 2011-09-09 19:10:51 -0400 | [diff] [blame^] | 532 | ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 533 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 534 | ext4_fsblk_t desc_count; |
| 535 | struct ext4_group_desc *gdp; |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 536 | ext4_group_t i; |
Theodore Ts'o | 8df9675 | 2009-05-01 08:50:38 -0400 | [diff] [blame] | 537 | ext4_group_t ngroups = ext4_get_groups_count(sb); |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 538 | #ifdef EXT4FS_DEBUG |
| 539 | struct ext4_super_block *es; |
| 540 | ext4_fsblk_t bitmap_count; |
Theodore Ts'o | 498e5f2 | 2008-11-05 00:14:04 -0500 | [diff] [blame] | 541 | unsigned int x; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 542 | struct buffer_head *bitmap_bh = NULL; |
| 543 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 544 | es = EXT4_SB(sb)->s_es; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 545 | desc_count = 0; |
| 546 | bitmap_count = 0; |
| 547 | gdp = NULL; |
| 548 | |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 549 | for (i = 0; i < ngroups; i++) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 550 | gdp = ext4_get_group_desc(sb, i, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 551 | if (!gdp) |
| 552 | continue; |
Theodore Ts'o | 021b65b | 2011-09-09 19:08:51 -0400 | [diff] [blame] | 553 | desc_count += ext4_free_group_clusters(sb, gdp); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 554 | brelse(bitmap_bh); |
Theodore Ts'o | 574ca17 | 2008-07-11 19:27:31 -0400 | [diff] [blame] | 555 | bitmap_bh = ext4_read_block_bitmap(sb, i); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 556 | if (bitmap_bh == NULL) |
| 557 | continue; |
| 558 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 559 | x = ext4_count_free(bitmap_bh, sb->s_blocksize); |
Thadeu Lima de Souza Cascardo | 9fd9784 | 2009-01-26 19:26:26 -0500 | [diff] [blame] | 560 | printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n", |
Theodore Ts'o | 021b65b | 2011-09-09 19:08:51 -0400 | [diff] [blame] | 561 | i, ext4_free_group_clusters(sb, gdp), x); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 562 | bitmap_count += x; |
| 563 | } |
| 564 | brelse(bitmap_bh); |
Theodore Ts'o | 5dee543 | 2011-09-09 19:10:51 -0400 | [diff] [blame^] | 565 | printk(KERN_DEBUG "ext4_count_free_clusters: stored = %llu" |
| 566 | ", computed = %llu, %llu\n", |
| 567 | EXT4_B2C(sbi, ext4_free_blocks_count(es)), |
Theodore Ts'o | 4776004 | 2008-09-08 23:00:52 -0400 | [diff] [blame] | 568 | desc_count, bitmap_count); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 569 | return bitmap_count; |
| 570 | #else |
| 571 | desc_count = 0; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 572 | for (i = 0; i < ngroups; i++) { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 573 | gdp = ext4_get_group_desc(sb, i, NULL); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 574 | if (!gdp) |
| 575 | continue; |
Theodore Ts'o | 021b65b | 2011-09-09 19:08:51 -0400 | [diff] [blame] | 576 | desc_count += ext4_free_group_clusters(sb, gdp); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 577 | } |
| 578 | |
| 579 | return desc_count; |
| 580 | #endif |
| 581 | } |
| 582 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 583 | static inline int test_root(ext4_group_t a, int b) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 584 | { |
| 585 | int num = b; |
| 586 | |
| 587 | while (a > num) |
| 588 | num *= b; |
| 589 | return num == a; |
| 590 | } |
| 591 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 592 | static int ext4_group_sparse(ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 593 | { |
| 594 | if (group <= 1) |
| 595 | return 1; |
| 596 | if (!(group & 1)) |
| 597 | return 0; |
| 598 | return (test_root(group, 7) || test_root(group, 5) || |
| 599 | test_root(group, 3)); |
| 600 | } |
| 601 | |
| 602 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 603 | * 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] | 604 | * @sb: superblock for filesystem |
| 605 | * @group: group number to check |
| 606 | * |
| 607 | * Return the number of blocks used by the superblock (primary or backup) |
| 608 | * in this group. Currently this will be only 0 or 1. |
| 609 | */ |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 610 | 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] | 611 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 612 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, |
| 613 | EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) && |
| 614 | !ext4_group_sparse(group)) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 615 | return 0; |
| 616 | return 1; |
| 617 | } |
| 618 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 619 | static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, |
| 620 | ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 621 | { |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 622 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 623 | ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb); |
| 624 | ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 625 | |
| 626 | if (group == first || group == first + 1 || group == last) |
| 627 | return 1; |
| 628 | return 0; |
| 629 | } |
| 630 | |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 631 | static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, |
| 632 | ext4_group_t group) |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 633 | { |
Theodore Ts'o | 8dadb19 | 2009-11-23 07:24:38 -0500 | [diff] [blame] | 634 | if (!ext4_bg_has_super(sb, group)) |
| 635 | return 0; |
| 636 | |
| 637 | if (EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG)) |
| 638 | return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
| 639 | else |
| 640 | return EXT4_SB(sb)->s_gdb_count; |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 641 | } |
| 642 | |
| 643 | /** |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 644 | * 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] | 645 | * @sb: superblock for filesystem |
| 646 | * @group: group number to check |
| 647 | * |
| 648 | * Return the number of blocks used by the group descriptor table |
| 649 | * (primary or backup) in this group. In the future there may be a |
| 650 | * different number of descriptor blocks in each group. |
| 651 | */ |
Avantika Mathur | fd2d429 | 2008-01-28 23:58:27 -0500 | [diff] [blame] | 652 | 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] | 653 | { |
| 654 | unsigned long first_meta_bg = |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 655 | le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); |
| 656 | unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 657 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 658 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) || |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 659 | metagroup < first_meta_bg) |
Theodore Ts'o | af5bc92 | 2008-09-08 22:25:24 -0400 | [diff] [blame] | 660 | return ext4_bg_num_gdb_nometa(sb, group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 661 | |
Mingming Cao | 617ba13 | 2006-10-11 01:20:53 -0700 | [diff] [blame] | 662 | return ext4_bg_num_gdb_meta(sb,group); |
Dave Kleikamp | ac27a0e | 2006-10-11 01:20:50 -0700 | [diff] [blame] | 663 | |
| 664 | } |
Theodore Ts'o | c2ea3fd | 2008-10-10 09:40:52 -0400 | [diff] [blame] | 665 | |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 666 | /* |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 667 | * This function returns the number of file system metadata clusters at |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 668 | * the beginning of a block group, including the reserved gdt blocks. |
| 669 | */ |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 670 | unsigned ext4_num_base_meta_clusters(struct super_block *sb, |
| 671 | ext4_group_t block_group) |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 672 | { |
| 673 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 674 | unsigned num; |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 675 | |
| 676 | /* Check for superblock and gdt backups in this group */ |
| 677 | num = ext4_bg_has_super(sb, block_group); |
| 678 | |
| 679 | if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) || |
| 680 | block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) * |
| 681 | sbi->s_desc_per_block) { |
| 682 | if (num) { |
| 683 | num += ext4_bg_num_gdb(sb, block_group); |
| 684 | num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks); |
| 685 | } |
| 686 | } else { /* For META_BG_BLOCK_GROUPS */ |
| 687 | num += ext4_bg_num_gdb(sb, block_group); |
| 688 | } |
Theodore Ts'o | d5b8f31 | 2011-09-09 18:44:51 -0400 | [diff] [blame] | 689 | return EXT4_NUM_B2C(sbi, num); |
Theodore Ts'o | 49f7f9a | 2011-09-09 18:40:51 -0400 | [diff] [blame] | 690 | } |
Eric Sandeen | f86186b | 2011-06-28 10:01:31 -0400 | [diff] [blame] | 691 | /** |
| 692 | * ext4_inode_to_goal_block - return a hint for block allocation |
| 693 | * @inode: inode for block allocation |
| 694 | * |
| 695 | * Return the ideal location to start allocating blocks for a |
| 696 | * newly created inode. |
| 697 | */ |
| 698 | ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode) |
| 699 | { |
| 700 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 701 | ext4_group_t block_group; |
| 702 | ext4_grpblk_t colour; |
| 703 | int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); |
| 704 | ext4_fsblk_t bg_start; |
| 705 | ext4_fsblk_t last_block; |
| 706 | |
| 707 | block_group = ei->i_block_group; |
| 708 | if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { |
| 709 | /* |
| 710 | * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME |
| 711 | * block groups per flexgroup, reserve the first block |
| 712 | * group for directories and special files. Regular |
| 713 | * files will start at the second block group. This |
| 714 | * tends to speed up directory access and improves |
| 715 | * fsck times. |
| 716 | */ |
| 717 | block_group &= ~(flex_size-1); |
| 718 | if (S_ISREG(inode->i_mode)) |
| 719 | block_group++; |
| 720 | } |
| 721 | bg_start = ext4_group_first_block_no(inode->i_sb, block_group); |
| 722 | last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; |
| 723 | |
| 724 | /* |
| 725 | * If we are doing delayed allocation, we don't need take |
| 726 | * colour into account. |
| 727 | */ |
| 728 | if (test_opt(inode->i_sb, DELALLOC)) |
| 729 | return bg_start; |
| 730 | |
| 731 | if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) |
| 732 | colour = (current->pid % 16) * |
| 733 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
| 734 | else |
| 735 | colour = (current->pid % 16) * ((last_block - bg_start) / 16); |
| 736 | return bg_start + colour; |
| 737 | } |
| 738 | |