blob: cd6ea29be6457b52b442ec0a159e5732fad9563f [file] [log] [blame]
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001/*
Mingming Cao617ba132006-10-11 01:20:53 -07002 * linux/fs/ext4/balloc.c
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003 *
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>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070017#include <linux/quotaops.h>
18#include <linux/buffer_head.h>
Christoph Hellwig3dcf5452008-04-29 18:13:32 -040019#include "ext4.h"
20#include "ext4_jbd2.h"
Aneesh Kumar K.Ve21675d2009-01-05 21:36:02 -050021#include "mballoc.h"
Christoph Hellwig3dcf5452008-04-29 18:13:32 -040022
Jiaying Zhang0562e0b2011-03-21 21:38:05 -040023#include <trace/events/ext4.h>
24
Eric Sandeen5f163cc2012-01-04 22:33:28 -050025static unsigned ext4_num_base_meta_clusters(struct super_block *sb,
26 ext4_group_t block_group);
Dave Kleikampac27a0e2006-10-11 01:20:50 -070027/*
28 * balloc.c contains the blocks allocation and deallocation routines
29 */
30
31/*
Lukas Czernerbd862982013-04-03 23:32:34 -040032 * Calculate block group number for a given block number
33 */
34ext4_group_t ext4_get_group_number(struct super_block *sb,
35 ext4_fsblk_t block)
36{
37 ext4_group_t group;
38
39 if (test_opt2(sb, STD_GROUP_SIZE))
Theodore Ts'o960fd8562013-07-05 23:11:16 -040040 group = (block -
41 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) >>
Lukas Czernerbd862982013-04-03 23:32:34 -040042 (EXT4_BLOCK_SIZE_BITS(sb) + EXT4_CLUSTER_BITS(sb) + 3);
43 else
44 ext4_get_group_no_and_offset(sb, block, &group, NULL);
45 return group;
46}
47
48/*
Theodore Ts'o3212a802011-09-09 18:46:51 -040049 * Calculate the block group number and offset into the block/cluster
50 * allocation bitmap, given a block number
Andrew Morton72b64b52006-10-11 01:21:18 -070051 */
52void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
Avantika Mathurfd2d4292008-01-28 23:58:27 -050053 ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp)
Andrew Morton72b64b52006-10-11 01:21:18 -070054{
Dave Kleikamp8c55e202007-05-24 13:04:54 -040055 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
Andrew Morton72b64b52006-10-11 01:21:18 -070056 ext4_grpblk_t offset;
57
Dave Kleikamp8c55e202007-05-24 13:04:54 -040058 blocknr = blocknr - le32_to_cpu(es->s_first_data_block);
Theodore Ts'o3212a802011-09-09 18:46:51 -040059 offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)) >>
60 EXT4_SB(sb)->s_cluster_bits;
Andrew Morton72b64b52006-10-11 01:21:18 -070061 if (offsetp)
62 *offsetp = offset;
63 if (blockgrpp)
Dave Kleikamp8c55e202007-05-24 13:04:54 -040064 *blockgrpp = blocknr;
Andrew Morton72b64b52006-10-11 01:21:18 -070065
66}
67
Lukas Czerner68911002013-04-03 22:12:52 -040068/*
69 * Check whether the 'block' lives within the 'block_group'. Returns 1 if so
70 * and 0 otherwise.
71 */
72static inline int ext4_block_in_group(struct super_block *sb,
73 ext4_fsblk_t block,
74 ext4_group_t block_group)
Jose R. Santos0bf7e832008-06-03 14:07:29 -040075{
76 ext4_group_t actual_group;
Lukas Czerner68911002013-04-03 22:12:52 -040077
Lukas Czernerbd862982013-04-03 23:32:34 -040078 actual_group = ext4_get_group_number(sb, block);
Lukas Czerner68911002013-04-03 22:12:52 -040079 return (actual_group == block_group) ? 1 : 0;
Jose R. Santos0bf7e832008-06-03 14:07:29 -040080}
81
Theodore Ts'od5b8f312011-09-09 18:44:51 -040082/* Return the number of clusters used for file system metadata; this
83 * represents the overhead needed by the file system.
84 */
Stephen Hemmingerc1978552014-05-12 10:50:23 -040085static unsigned ext4_num_overhead_clusters(struct super_block *sb,
86 ext4_group_t block_group,
87 struct ext4_group_desc *gdp)
Jose R. Santos0bf7e832008-06-03 14:07:29 -040088{
Theodore Ts'od5b8f312011-09-09 18:44:51 -040089 unsigned num_clusters;
90 int block_cluster = -1, inode_cluster = -1, itbl_cluster = -1, i, c;
91 ext4_fsblk_t start = ext4_group_first_block_no(sb, block_group);
92 ext4_fsblk_t itbl_blk;
Jose R. Santos0bf7e832008-06-03 14:07:29 -040093 struct ext4_sb_info *sbi = EXT4_SB(sb);
Jose R. Santos0bf7e832008-06-03 14:07:29 -040094
Theodore Ts'od5b8f312011-09-09 18:44:51 -040095 /* This is the number of clusters used by the superblock,
96 * block group descriptors, and reserved block group
97 * descriptor blocks */
98 num_clusters = ext4_num_base_meta_clusters(sb, block_group);
Jose R. Santos0bf7e832008-06-03 14:07:29 -040099
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400100 /*
101 * For the allocation bitmaps and inode table, we first need
102 * to check to see if the block is in the block group. If it
103 * is, then check to see if the cluster is already accounted
104 * for in the clusters used for the base metadata cluster, or
105 * if we can increment the base metadata cluster to include
106 * that block. Otherwise, we will have to track the cluster
107 * used for the allocation bitmap or inode table explicitly.
108 * Normally all of these blocks are contiguous, so the special
109 * case handling shouldn't be necessary except for *very*
110 * unusual file system layouts.
111 */
112 if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) {
Theodore Ts'ob0dd6b72012-06-07 18:56:06 -0400113 block_cluster = EXT4_B2C(sbi,
114 ext4_block_bitmap(sb, gdp) - start);
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400115 if (block_cluster < num_clusters)
116 block_cluster = -1;
117 else if (block_cluster == num_clusters) {
118 num_clusters++;
119 block_cluster = -1;
Jose R. Santos0bf7e832008-06-03 14:07:29 -0400120 }
121 }
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400122
123 if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) {
124 inode_cluster = EXT4_B2C(sbi,
Theodore Ts'ob0dd6b72012-06-07 18:56:06 -0400125 ext4_inode_bitmap(sb, gdp) - start);
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400126 if (inode_cluster < num_clusters)
127 inode_cluster = -1;
128 else if (inode_cluster == num_clusters) {
129 num_clusters++;
130 inode_cluster = -1;
131 }
132 }
133
134 itbl_blk = ext4_inode_table(sb, gdp);
135 for (i = 0; i < sbi->s_itb_per_group; i++) {
136 if (ext4_block_in_group(sb, itbl_blk + i, block_group)) {
Theodore Ts'ob0dd6b72012-06-07 18:56:06 -0400137 c = EXT4_B2C(sbi, itbl_blk + i - start);
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400138 if ((c < num_clusters) || (c == inode_cluster) ||
139 (c == block_cluster) || (c == itbl_cluster))
140 continue;
141 if (c == num_clusters) {
142 num_clusters++;
143 continue;
144 }
145 num_clusters++;
146 itbl_cluster = c;
147 }
148 }
149
150 if (block_cluster != -1)
151 num_clusters++;
152 if (inode_cluster != -1)
153 num_clusters++;
154
155 return num_clusters;
Jose R. Santos0bf7e832008-06-03 14:07:29 -0400156}
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -0400157
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400158static unsigned int num_clusters_in_group(struct super_block *sb,
159 ext4_group_t block_group)
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400160{
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400161 unsigned int blocks;
162
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400163 if (block_group == ext4_get_groups_count(sb) - 1) {
164 /*
165 * Even though mke2fs always initializes the first and
166 * last group, just in case some other tool was used,
167 * we need to make sure we calculate the right free
168 * blocks.
169 */
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400170 blocks = ext4_blocks_count(EXT4_SB(sb)->s_es) -
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400171 ext4_group_first_block_no(sb, block_group);
172 } else
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400173 blocks = EXT4_BLOCKS_PER_GROUP(sb);
174 return EXT4_NUM_B2C(EXT4_SB(sb), blocks);
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400175}
176
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400177/* Initializes an uninitialized block bitmap */
Dmitry Monakhovaef48852014-10-13 03:42:12 -0400178static int ext4_init_block_bitmap(struct super_block *sb,
Stephen Hemmingerc1978552014-05-12 10:50:23 -0400179 struct buffer_head *bh,
180 ext4_group_t block_group,
181 struct ext4_group_desc *gdp)
Andreas Dilger717d50e2007-10-16 18:38:25 -0400182{
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400183 unsigned int bit, bit_max;
Andreas Dilger717d50e2007-10-16 18:38:25 -0400184 struct ext4_sb_info *sbi = EXT4_SB(sb);
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400185 ext4_fsblk_t start, tmp;
186 int flex_bg = 0;
Darrick J. Wongbdfb6ff2013-08-28 18:46:56 -0400187 struct ext4_group_info *grp;
Andreas Dilger717d50e2007-10-16 18:38:25 -0400188
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400189 J_ASSERT_BH(bh, buffer_locked(bh));
Andreas Dilger717d50e2007-10-16 18:38:25 -0400190
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400191 /* If checksum is bad mark all blocks used to prevent allocation
192 * essentially implementing a per-group read-only flag. */
Darrick J. Wongfeb0ab32012-04-29 18:45:10 -0400193 if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
Darrick J. Wongbdfb6ff2013-08-28 18:46:56 -0400194 grp = ext4_get_group_info(sb, block_group);
Namjae Jeone43bb4e2014-06-26 10:11:53 -0400195 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
196 percpu_counter_sub(&sbi->s_freeclusters_counter,
197 grp->bb_free);
Darrick J. Wongbdfb6ff2013-08-28 18:46:56 -0400198 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
Namjae Jeone43bb4e2014-06-26 10:11:53 -0400199 if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
200 int count;
201 count = ext4_free_inodes_count(sb, gdp);
202 percpu_counter_sub(&sbi->s_freeinodes_counter,
203 count);
204 }
Darrick J. Wongbdfb6ff2013-08-28 18:46:56 -0400205 set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
Dmitry Monakhovaef48852014-10-13 03:42:12 -0400206 return -EIO;
Andreas Dilger717d50e2007-10-16 18:38:25 -0400207 }
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400208 memset(bh->b_data, 0, sb->s_blocksize);
Andreas Dilger717d50e2007-10-16 18:38:25 -0400209
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400210 bit_max = ext4_num_base_meta_clusters(sb, block_group);
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400211 for (bit = 0; bit < bit_max; bit++)
212 ext4_set_bit(bit, bh->b_data);
Akinobu Mitad00a6d72008-04-17 10:38:59 -0400213
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400214 start = ext4_group_first_block_no(sb, block_group);
Andreas Dilger717d50e2007-10-16 18:38:25 -0400215
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400216 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
217 flex_bg = 1;
Andreas Dilger717d50e2007-10-16 18:38:25 -0400218
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400219 /* Set bits for block and inode bitmaps, and inode table */
220 tmp = ext4_block_bitmap(sb, gdp);
221 if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400222 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
Andreas Dilger717d50e2007-10-16 18:38:25 -0400223
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400224 tmp = ext4_inode_bitmap(sb, gdp);
225 if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400226 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400227
228 tmp = ext4_inode_table(sb, gdp);
229 for (; tmp < ext4_inode_table(sb, gdp) +
230 sbi->s_itb_per_group; tmp++) {
Jose R. Santos0bf7e832008-06-03 14:07:29 -0400231 if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400232 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
Andreas Dilger717d50e2007-10-16 18:38:25 -0400233 }
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400234
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400235 /*
236 * Also if the number of blocks within the group is less than
237 * the blocksize * 8 ( which is the size of bitmap ), set rest
238 * of the block bitmap to 1
239 */
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400240 ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group),
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400241 sb->s_blocksize * 8, bh->b_data);
Tao Ma79f1ba42012-10-22 00:34:32 -0400242 ext4_block_bitmap_csum_set(sb, block_group, gdp, bh);
Darrick J. Wongfeb0ab32012-04-29 18:45:10 -0400243 ext4_group_desc_csum_set(sb, block_group, gdp);
Dmitry Monakhovaef48852014-10-13 03:42:12 -0400244 return 0;
Andreas Dilger717d50e2007-10-16 18:38:25 -0400245}
246
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400247/* Return the number of free blocks in a block group. It is used when
248 * the block bitmap is uninitialized, so we can't just count the bits
249 * in the bitmap. */
Theodore Ts'ocff1dfd72011-09-09 19:12:51 -0400250unsigned ext4_free_clusters_after_init(struct super_block *sb,
251 ext4_group_t block_group,
252 struct ext4_group_desc *gdp)
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400253{
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400254 return num_clusters_in_group(sb, block_group) -
255 ext4_num_overhead_clusters(sb, block_group, gdp);
Theodore Ts'ofd034a82011-09-09 18:42:51 -0400256}
Andreas Dilger717d50e2007-10-16 18:38:25 -0400257
Andrew Morton72b64b52006-10-11 01:21:18 -0700258/*
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700259 * The free blocks are managed by bitmaps. A file system contains several
260 * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
261 * block for inodes, N blocks for the inode table and data blocks.
262 *
263 * The file system contains group descriptors which are located after the
264 * super block. Each descriptor contains the number of the bitmap block and
265 * the free blocks count in the block. The descriptors are loaded in memory
Aneesh Kumar K.Ve6274322007-02-20 13:57:58 -0800266 * when a file system is mounted (see ext4_fill_super).
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700267 */
268
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700269/**
Mingming Cao617ba132006-10-11 01:20:53 -0700270 * ext4_get_group_desc() -- load group descriptor from disk
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700271 * @sb: super block
272 * @block_group: given block group
273 * @bh: pointer to the buffer head to store the block
274 * group descriptor
275 */
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400276struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb,
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500277 ext4_group_t block_group,
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400278 struct buffer_head **bh)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700279{
Theodore Ts'o498e5f22008-11-05 00:14:04 -0500280 unsigned int group_desc;
281 unsigned int offset;
Theodore Ts'o8df96752009-05-01 08:50:38 -0400282 ext4_group_t ngroups = ext4_get_groups_count(sb);
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400283 struct ext4_group_desc *desc;
Mingming Cao617ba132006-10-11 01:20:53 -0700284 struct ext4_sb_info *sbi = EXT4_SB(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700285
Theodore Ts'o8df96752009-05-01 08:50:38 -0400286 if (block_group >= ngroups) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500287 ext4_error(sb, "block_group >= groups_count - block_group = %u,"
288 " groups_count = %u", block_group, ngroups);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700289
290 return NULL;
291 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700292
Mingming Cao617ba132006-10-11 01:20:53 -0700293 group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
294 offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700295 if (!sbi->s_group_desc[group_desc]) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500296 ext4_error(sb, "Group descriptor not loaded - "
Theodore Ts'o498e5f22008-11-05 00:14:04 -0500297 "block_group = %u, group_desc = %u, desc = %u",
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400298 block_group, group_desc, offset);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700299 return NULL;
300 }
301
Alexandre Ratchov0d1ee422006-10-11 01:21:14 -0700302 desc = (struct ext4_group_desc *)(
303 (__u8 *)sbi->s_group_desc[group_desc]->b_data +
304 offset * EXT4_DESC_SIZE(sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700305 if (bh)
306 *bh = sbi->s_group_desc[group_desc];
Alexandre Ratchov0d1ee422006-10-11 01:21:14 -0700307 return desc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700308}
309
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400310/*
311 * Return the block number which was discovered to be invalid, or 0 if
312 * the block bitmap is valid.
313 */
314static ext4_fsblk_t ext4_valid_block_bitmap(struct super_block *sb,
315 struct ext4_group_desc *desc,
Darrick J. Wongdbde0ab2013-08-28 15:59:51 -0400316 ext4_group_t block_group,
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400317 struct buffer_head *bh)
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500318{
Darrick J. Wonge674e5c2014-05-12 10:17:55 -0400319 struct ext4_sb_info *sbi = EXT4_SB(sb);
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500320 ext4_grpblk_t offset;
321 ext4_grpblk_t next_zero_bit;
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400322 ext4_fsblk_t blk;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500323 ext4_fsblk_t group_first_block;
324
325 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) {
326 /* with FLEX_BG, the inode/block bitmaps and itable
327 * blocks may not be in the group at all
328 * so the bitmap validation will be skipped for those groups
329 * or it has to also read the block group where the bitmaps
330 * are located to verify they are set.
331 */
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400332 return 0;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500333 }
334 group_first_block = ext4_group_first_block_no(sb, block_group);
335
336 /* check whether block bitmap block number is set */
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400337 blk = ext4_block_bitmap(sb, desc);
338 offset = blk - group_first_block;
Darrick J. Wonge674e5c2014-05-12 10:17:55 -0400339 if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500340 /* bad block bitmap */
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400341 return blk;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500342
343 /* check whether the inode bitmap block number is set */
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400344 blk = ext4_inode_bitmap(sb, desc);
345 offset = blk - group_first_block;
Darrick J. Wonge674e5c2014-05-12 10:17:55 -0400346 if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500347 /* bad block bitmap */
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400348 return blk;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500349
350 /* check whether the inode table block number is set */
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400351 blk = ext4_inode_table(sb, desc);
352 offset = blk - group_first_block;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500353 next_zero_bit = ext4_find_next_zero_bit(bh->b_data,
Darrick J. Wonge674e5c2014-05-12 10:17:55 -0400354 EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group),
355 EXT4_B2C(sbi, offset));
356 if (next_zero_bit <
357 EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group))
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400358 /* bad bitmap for inode tables */
359 return blk;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500360 return 0;
361}
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400362
Stephen Hemmingerc1978552014-05-12 10:50:23 -0400363static void ext4_validate_block_bitmap(struct super_block *sb,
364 struct ext4_group_desc *desc,
365 ext4_group_t block_group,
366 struct buffer_head *bh)
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400367{
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400368 ext4_fsblk_t blk;
Darrick J. Wong163a2032013-08-28 17:35:51 -0400369 struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
Namjae Jeone43bb4e2014-06-26 10:11:53 -0400370 struct ext4_sb_info *sbi = EXT4_SB(sb);
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400371
Lukas Czerner41e5b7e2015-06-08 11:18:52 -0400372 if (buffer_verified(bh) || EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400373 return;
374
375 ext4_lock_group(sb, block_group);
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400376 blk = ext4_valid_block_bitmap(sb, desc, block_group, bh);
377 if (unlikely(blk != 0)) {
378 ext4_unlock_group(sb, block_group);
379 ext4_error(sb, "bg %u: block %llu: invalid block bitmap",
380 block_group, blk);
Namjae Jeone43bb4e2014-06-26 10:11:53 -0400381 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
382 percpu_counter_sub(&sbi->s_freeclusters_counter,
383 grp->bb_free);
Darrick J. Wong163a2032013-08-28 17:35:51 -0400384 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400385 return;
386 }
387 if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group,
Tao Ma79f1ba42012-10-22 00:34:32 -0400388 desc, bh))) {
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400389 ext4_unlock_group(sb, block_group);
390 ext4_error(sb, "bg %u: bad block bitmap checksum", block_group);
Namjae Jeone43bb4e2014-06-26 10:11:53 -0400391 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
392 percpu_counter_sub(&sbi->s_freeclusters_counter,
393 grp->bb_free);
Darrick J. Wong163a2032013-08-28 17:35:51 -0400394 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
Theodore Ts'o7a4c5de2012-08-10 13:57:52 -0400395 return;
396 }
397 set_buffer_verified(bh);
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400398 ext4_unlock_group(sb, block_group);
399}
400
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700401/**
Eryu Guan15b49132013-01-12 16:33:25 -0500402 * ext4_read_block_bitmap_nowait()
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700403 * @sb: super block
404 * @block_group: given block group
405 *
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500406 * Read the bitmap for a given block_group,and validate the
407 * bits for block/inode/inode tables are set in the bitmaps
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700408 *
409 * Return buffer_head on success or NULL in case of failure.
410 */
Andreas Dilger717d50e2007-10-16 18:38:25 -0400411struct buffer_head *
Theodore Ts'o813e5722012-02-20 17:52:46 -0500412ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700413{
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400414 struct ext4_group_desc *desc;
Theodore Ts'o813e5722012-02-20 17:52:46 -0500415 struct buffer_head *bh;
Aneesh Kumar K.V7c9e69f2007-10-16 23:27:02 -0700416 ext4_fsblk_t bitmap_blk;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700417
Andreas Dilger717d50e2007-10-16 18:38:25 -0400418 desc = ext4_get_group_desc(sb, block_group, NULL);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700419 if (!desc)
Aneesh Kumar K.V7c9e69f2007-10-16 23:27:02 -0700420 return NULL;
421 bitmap_blk = ext4_block_bitmap(sb, desc);
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500422 bh = sb_getblk(sb, bitmap_blk);
423 if (unlikely(!bh)) {
Theodore Ts'o813e5722012-02-20 17:52:46 -0500424 ext4_error(sb, "Cannot get buffer for block bitmap - "
425 "block_group = %u, block_bitmap = %llu",
426 block_group, bitmap_blk);
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500427 return NULL;
428 }
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500429
430 if (bitmap_uptodate(bh))
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400431 goto verify;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500432
Frederic Bohec806e682008-10-10 08:09:18 -0400433 lock_buffer(bh);
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500434 if (bitmap_uptodate(bh)) {
435 unlock_buffer(bh);
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400436 goto verify;
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500437 }
Aneesh Kumar K.V955ce5f2009-05-02 20:35:09 -0400438 ext4_lock_group(sb, block_group);
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500439 if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
Dmitry Monakhovaef48852014-10-13 03:42:12 -0400440 int err;
441
442 err = ext4_init_block_bitmap(sb, bh, block_group, desc);
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500443 set_bitmap_uptodate(bh);
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500444 set_buffer_uptodate(bh);
Aneesh Kumar K.V955ce5f2009-05-02 20:35:09 -0400445 ext4_unlock_group(sb, block_group);
Aneesh Kumar K.V3300bed2009-01-03 22:33:39 -0500446 unlock_buffer(bh);
Dmitry Monakhovaef48852014-10-13 03:42:12 -0400447 if (err)
448 ext4_error(sb, "Checksum bad for grp %u", block_group);
Lukas Czerner41e5b7e2015-06-08 11:18:52 -0400449 goto verify;
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500450 }
Aneesh Kumar K.V955ce5f2009-05-02 20:35:09 -0400451 ext4_unlock_group(sb, block_group);
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500452 if (buffer_uptodate(bh)) {
453 /*
454 * if not uninit if bh is uptodate,
455 * bitmap is also uptodate
456 */
457 set_bitmap_uptodate(bh);
458 unlock_buffer(bh);
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400459 goto verify;
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500460 }
461 /*
Theodore Ts'o813e5722012-02-20 17:52:46 -0500462 * submit the buffer_head for reading
Aneesh Kumar K.V2ccb5fb2009-01-05 21:49:55 -0500463 */
Theodore Ts'o813e5722012-02-20 17:52:46 -0500464 set_buffer_new(bh);
Jiaying Zhang0562e0b2011-03-21 21:38:05 -0400465 trace_ext4_read_block_bitmap_load(sb, block_group);
Theodore Ts'o813e5722012-02-20 17:52:46 -0500466 bh->b_end_io = ext4_end_bitmap_read;
467 get_bh(bh);
Theodore Ts'o9f203502013-04-20 15:46:17 -0400468 submit_bh(READ | REQ_META | REQ_PRIO, bh);
Theodore Ts'o813e5722012-02-20 17:52:46 -0500469 return bh;
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400470verify:
471 ext4_validate_block_bitmap(sb, desc, block_group, bh);
Darrick J. Wong48d9eb92013-08-28 15:35:27 -0400472 if (buffer_verified(bh))
473 return bh;
474 put_bh(bh);
475 return NULL;
Theodore Ts'o813e5722012-02-20 17:52:46 -0500476}
477
478/* Returns 0 on success, 1 on error */
479int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group,
480 struct buffer_head *bh)
481{
482 struct ext4_group_desc *desc;
483
484 if (!buffer_new(bh))
485 return 0;
486 desc = ext4_get_group_desc(sb, block_group, NULL);
487 if (!desc)
488 return 1;
489 wait_on_buffer(bh);
490 if (!buffer_uptodate(bh)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500491 ext4_error(sb, "Cannot read block bitmap - "
Theodore Ts'o813e5722012-02-20 17:52:46 -0500492 "block_group = %u, block_bitmap = %llu",
Heiko Carstensd4dc4622012-02-20 17:57:24 -0500493 block_group, (unsigned long long) bh->b_blocknr);
Theodore Ts'o813e5722012-02-20 17:52:46 -0500494 return 1;
495 }
496 clear_buffer_new(bh);
497 /* Panic or remount fs read-only if block bitmap is invalid */
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -0400498 ext4_validate_block_bitmap(sb, desc, block_group, bh);
Darrick J. Wong48d9eb92013-08-28 15:35:27 -0400499 /* ...but check for error just in case errors=continue. */
500 return !buffer_verified(bh);
Theodore Ts'o813e5722012-02-20 17:52:46 -0500501}
502
503struct buffer_head *
504ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
505{
506 struct buffer_head *bh;
507
508 bh = ext4_read_block_bitmap_nowait(sb, block_group);
Eryu Guan15b49132013-01-12 16:33:25 -0500509 if (!bh)
510 return NULL;
Theodore Ts'o813e5722012-02-20 17:52:46 -0500511 if (ext4_wait_block_bitmap(sb, block_group, bh)) {
512 put_bh(bh);
Aneesh Kumar K.Vabcb2942008-01-28 23:58:27 -0500513 return NULL;
514 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700515 return bh;
516}
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700517
518/**
Theodore Ts'odf55c992011-09-09 19:16:51 -0400519 * ext4_has_free_clusters()
Eric Sandeen8c3bf8a02008-10-28 00:08:12 -0400520 * @sbi: in-core super block structure.
Theodore Ts'odf55c992011-09-09 19:16:51 -0400521 * @nclusters: number of needed blocks
522 * @flags: flags from ext4_mb_new_blocks()
Eric Sandeen8c3bf8a02008-10-28 00:08:12 -0400523 *
Theodore Ts'odf55c992011-09-09 19:16:51 -0400524 * Check if filesystem has nclusters free & available for allocation.
Eric Sandeen8c3bf8a02008-10-28 00:08:12 -0400525 * On success return 1, return 0 on failure.
526 */
Theodore Ts'odf55c992011-09-09 19:16:51 -0400527static int ext4_has_free_clusters(struct ext4_sb_info *sbi,
528 s64 nclusters, unsigned int flags)
Aneesh Kumar K.Va30d542a2008-10-09 10:56:23 -0400529{
Lukas Czerner27dd4382013-04-09 22:11:22 -0400530 s64 free_clusters, dirty_clusters, rsv, resv_clusters;
Theodore Ts'o57042652011-09-09 18:56:51 -0400531 struct percpu_counter *fcc = &sbi->s_freeclusters_counter;
Theodore Ts'odf55c992011-09-09 19:16:51 -0400532 struct percpu_counter *dcc = &sbi->s_dirtyclusters_counter;
Aneesh Kumar K.Va30d542a2008-10-09 10:56:23 -0400533
Theodore Ts'odf55c992011-09-09 19:16:51 -0400534 free_clusters = percpu_counter_read_positive(fcc);
535 dirty_clusters = percpu_counter_read_positive(dcc);
Lukas Czerner27dd4382013-04-09 22:11:22 -0400536 resv_clusters = atomic64_read(&sbi->s_resv_clusters);
Lukas Czerner304e2202013-02-22 15:27:52 -0500537
538 /*
539 * r_blocks_count should always be multiple of the cluster ratio so
540 * we are safe to do a plane bit shift only.
541 */
Lukas Czerner27dd4382013-04-09 22:11:22 -0400542 rsv = (ext4_r_blocks_count(sbi->s_es) >> sbi->s_cluster_bits) +
543 resv_clusters;
Aneesh Kumar K.Va30d542a2008-10-09 10:56:23 -0400544
Lukas Czerner27dd4382013-04-09 22:11:22 -0400545 if (free_clusters - (nclusters + rsv + dirty_clusters) <
Theodore Ts'odf55c992011-09-09 19:16:51 -0400546 EXT4_FREECLUSTERS_WATERMARK) {
Lukas Czerner304e2202013-02-22 15:27:52 -0500547 free_clusters = percpu_counter_sum_positive(fcc);
Theodore Ts'odf55c992011-09-09 19:16:51 -0400548 dirty_clusters = percpu_counter_sum_positive(dcc);
Aneesh Kumar K.V6bc6e632008-10-10 09:39:00 -0400549 }
Theodore Ts'odf55c992011-09-09 19:16:51 -0400550 /* Check whether we have space after accounting for current
551 * dirty clusters & root reserved clusters.
Aneesh Kumar K.V6bc6e632008-10-10 09:39:00 -0400552 */
Lukas Czerner27dd4382013-04-09 22:11:22 -0400553 if (free_clusters >= (rsv + nclusters + dirty_clusters))
Eric Sandeena9960312008-10-28 00:08:17 -0400554 return 1;
Aneesh Kumar K.V5c791612008-10-08 23:12:24 -0400555
Theodore Ts'odf55c992011-09-09 19:16:51 -0400556 /* Hm, nope. Are (enough) root reserved clusters available? */
Eric W. Biederman08cefc72012-02-07 15:41:49 -0800557 if (uid_eq(sbi->s_resuid, current_fsuid()) ||
558 (!gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) && in_group_p(sbi->s_resgid)) ||
Allison Henderson55f020d2011-05-25 07:41:26 -0400559 capable(CAP_SYS_RESOURCE) ||
Lukas Czerner27dd4382013-04-09 22:11:22 -0400560 (flags & EXT4_MB_USE_ROOT_BLOCKS)) {
Allison Henderson55f020d2011-05-25 07:41:26 -0400561
Lukas Czerner27dd4382013-04-09 22:11:22 -0400562 if (free_clusters >= (nclusters + dirty_clusters +
563 resv_clusters))
564 return 1;
565 }
566 /* No free blocks. Let's see if we can dip into reserved pool */
567 if (flags & EXT4_MB_USE_RESERVED) {
Theodore Ts'odf55c992011-09-09 19:16:51 -0400568 if (free_clusters >= (nclusters + dirty_clusters))
Eric Sandeena9960312008-10-28 00:08:17 -0400569 return 1;
570 }
571
572 return 0;
Aneesh Kumar K.Va30d542a2008-10-09 10:56:23 -0400573}
Mingming Cao07031432008-07-11 19:27:31 -0400574
Theodore Ts'oe7d5f312011-09-09 19:14:51 -0400575int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
576 s64 nclusters, unsigned int flags)
Eric Sandeen8c3bf8a02008-10-28 00:08:12 -0400577{
Theodore Ts'odf55c992011-09-09 19:16:51 -0400578 if (ext4_has_free_clusters(sbi, nclusters, flags)) {
Theodore Ts'oe7d5f312011-09-09 19:14:51 -0400579 percpu_counter_add(&sbi->s_dirtyclusters_counter, nclusters);
Eric Sandeen8c3bf8a02008-10-28 00:08:12 -0400580 return 0;
581 } else
582 return -ENOSPC;
583}
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700584
585/**
Mingming Cao617ba132006-10-11 01:20:53 -0700586 * ext4_should_retry_alloc()
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700587 * @sb: super block
588 * @retries number of attemps has been made
589 *
Mingming Cao617ba132006-10-11 01:20:53 -0700590 * ext4_should_retry_alloc() is called when ENOSPC is returned, and if
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700591 * it is profitable to retry the operation, this function will wait
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300592 * for the current or committing transaction to complete, and then
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700593 * return TRUE.
594 *
595 * if the total number of retries exceed three times, return FALSE.
596 */
Mingming Cao617ba132006-10-11 01:20:53 -0700597int ext4_should_retry_alloc(struct super_block *sb, int *retries)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700598{
Theodore Ts'odf55c992011-09-09 19:16:51 -0400599 if (!ext4_has_free_clusters(EXT4_SB(sb), 1, 0) ||
Eric Sandeen8f64b322009-02-26 00:57:35 -0500600 (*retries)++ > 3 ||
601 !EXT4_SB(sb)->s_journal)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700602 return 0;
603
604 jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
605
Mingming Caodab291a2006-10-11 01:21:01 -0700606 return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700607}
608
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400609/*
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400610 * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks
611 *
612 * @handle: handle to this transaction
613 * @inode: file inode
614 * @goal: given target block(filesystem wide)
Aditya Kali7b415bf2011-09-09 19:04:51 -0400615 * @count: pointer to total number of clusters needed
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400616 * @errp: error code
617 *
Theodore Ts'o97df5d12008-12-12 12:41:28 -0500618 * Return 1st allocated block number on success, *count stores total account
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400619 * error stores in errp pointer
620 */
621ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
Allison Henderson55f020d2011-05-25 07:41:26 -0400622 ext4_fsblk_t goal, unsigned int flags,
623 unsigned long *count, int *errp)
Aneesh Kumar K.V654b4902008-07-11 19:27:31 -0400624{
Theodore Ts'o97df5d12008-12-12 12:41:28 -0500625 struct ext4_allocation_request ar;
Mingming Caod2a17632008-07-14 17:52:37 -0400626 ext4_fsblk_t ret;
Theodore Ts'o97df5d12008-12-12 12:41:28 -0500627
628 memset(&ar, 0, sizeof(ar));
629 /* Fill with neighbour allocated blocks */
630 ar.inode = inode;
631 ar.goal = goal;
632 ar.len = count ? *count : 1;
Allison Henderson55f020d2011-05-25 07:41:26 -0400633 ar.flags = flags;
Theodore Ts'o97df5d12008-12-12 12:41:28 -0500634
635 ret = ext4_mb_new_blocks(handle, &ar, errp);
636 if (count)
637 *count = ar.len;
Mingming Caod2a17632008-07-14 17:52:37 -0400638 /*
Eric Sandeen72b8ab92010-05-16 11:00:00 -0400639 * Account for the allocated meta blocks. We will never
640 * fail EDQUOT for metdata, but we do account for it.
Mingming Caod2a17632008-07-14 17:52:37 -0400641 */
Theodore Ts'oe3cf5d52014-09-04 18:07:25 -0400642 if (!(*errp) && (flags & EXT4_MB_DELALLOC_RESERVED)) {
Aditya Kali7b415bf2011-09-09 19:04:51 -0400643 dquot_alloc_block_nofail(inode,
644 EXT4_C2B(EXT4_SB(inode->i_sb), ar.len));
Mingming Caod2a17632008-07-14 17:52:37 -0400645 }
646 return ret;
647}
648
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700649/**
Theodore Ts'o5dee5432011-09-09 19:10:51 -0400650 * ext4_count_free_clusters() -- count filesystem free clusters
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700651 * @sb: superblock
652 *
Theodore Ts'o5dee5432011-09-09 19:10:51 -0400653 * Adds up the number of free clusters from each block group.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700654 */
Theodore Ts'o5dee5432011-09-09 19:10:51 -0400655ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700656{
Mingming Cao617ba132006-10-11 01:20:53 -0700657 ext4_fsblk_t desc_count;
658 struct ext4_group_desc *gdp;
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500659 ext4_group_t i;
Theodore Ts'o8df96752009-05-01 08:50:38 -0400660 ext4_group_t ngroups = ext4_get_groups_count(sb);
Darrick J. Wong2746f7a2013-10-31 11:46:31 -0400661 struct ext4_group_info *grp;
Mingming Cao617ba132006-10-11 01:20:53 -0700662#ifdef EXT4FS_DEBUG
663 struct ext4_super_block *es;
664 ext4_fsblk_t bitmap_count;
Theodore Ts'o498e5f22008-11-05 00:14:04 -0500665 unsigned int x;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700666 struct buffer_head *bitmap_bh = NULL;
667
Mingming Cao617ba132006-10-11 01:20:53 -0700668 es = EXT4_SB(sb)->s_es;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700669 desc_count = 0;
670 bitmap_count = 0;
671 gdp = NULL;
672
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700673 for (i = 0; i < ngroups; i++) {
Mingming Cao617ba132006-10-11 01:20:53 -0700674 gdp = ext4_get_group_desc(sb, i, NULL);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700675 if (!gdp)
676 continue;
Darrick J. Wong2746f7a2013-10-31 11:46:31 -0400677 grp = NULL;
678 if (EXT4_SB(sb)->s_group_info)
679 grp = ext4_get_group_info(sb, i);
680 if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
681 desc_count += ext4_free_group_clusters(sb, gdp);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700682 brelse(bitmap_bh);
Theodore Ts'o574ca172008-07-11 19:27:31 -0400683 bitmap_bh = ext4_read_block_bitmap(sb, i);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700684 if (bitmap_bh == NULL)
685 continue;
686
Theodore Ts'of6fb99c2012-06-30 19:14:57 -0400687 x = ext4_count_free(bitmap_bh->b_data,
Azat Khuzhin036acea2014-04-14 23:36:15 -0400688 EXT4_CLUSTERS_PER_GROUP(sb) / 8);
Thadeu Lima de Souza Cascardo9fd97842009-01-26 19:26:26 -0500689 printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n",
Theodore Ts'o021b65b2011-09-09 19:08:51 -0400690 i, ext4_free_group_clusters(sb, gdp), x);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700691 bitmap_count += x;
692 }
693 brelse(bitmap_bh);
Theodore Ts'o5dee5432011-09-09 19:10:51 -0400694 printk(KERN_DEBUG "ext4_count_free_clusters: stored = %llu"
695 ", computed = %llu, %llu\n",
Lukas Czerner810da242013-03-02 17:18:58 -0500696 EXT4_NUM_B2C(EXT4_SB(sb), ext4_free_blocks_count(es)),
Theodore Ts'o4776004f2008-09-08 23:00:52 -0400697 desc_count, bitmap_count);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700698 return bitmap_count;
699#else
700 desc_count = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700701 for (i = 0; i < ngroups; i++) {
Mingming Cao617ba132006-10-11 01:20:53 -0700702 gdp = ext4_get_group_desc(sb, i, NULL);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700703 if (!gdp)
704 continue;
Darrick J. Wong2746f7a2013-10-31 11:46:31 -0400705 grp = NULL;
706 if (EXT4_SB(sb)->s_group_info)
707 grp = ext4_get_group_info(sb, i);
708 if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
709 desc_count += ext4_free_group_clusters(sb, gdp);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700710 }
711
712 return desc_count;
713#endif
714}
715
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500716static inline int test_root(ext4_group_t a, int b)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700717{
Theodore Ts'of4afb4f2013-06-06 11:40:37 -0400718 while (1) {
719 if (a < b)
720 return 0;
721 if (a == b)
722 return 1;
723 if ((a % b) != 0)
724 return 0;
725 a = a / b;
726 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700727}
728
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700729/**
Mingming Cao617ba132006-10-11 01:20:53 -0700730 * ext4_bg_has_super - number of blocks used by the superblock in group
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700731 * @sb: superblock for filesystem
732 * @group: group number to check
733 *
734 * Return the number of blocks used by the superblock (primary or backup)
735 * in this group. Currently this will be only 0 or 1.
736 */
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500737int ext4_bg_has_super(struct super_block *sb, ext4_group_t group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700738{
Darrick J. Wong1beeef12014-05-12 10:16:06 -0400739 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
740
741 if (group == 0)
742 return 1;
743 if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_SPARSE_SUPER2)) {
744 if (group == le32_to_cpu(es->s_backup_bgs[0]) ||
745 group == le32_to_cpu(es->s_backup_bgs[1]))
746 return 1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700747 return 0;
Darrick J. Wong1beeef12014-05-12 10:16:06 -0400748 }
749 if ((group <= 1) || !EXT4_HAS_RO_COMPAT_FEATURE(sb,
750 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER))
751 return 1;
752 if (!(group & 1))
753 return 0;
754 if (test_root(group, 3) || (test_root(group, 5)) ||
755 test_root(group, 7))
756 return 1;
757
758 return 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700759}
760
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500761static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb,
762 ext4_group_t group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700763{
Mingming Cao617ba132006-10-11 01:20:53 -0700764 unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500765 ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb);
766 ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700767
768 if (group == first || group == first + 1 || group == last)
769 return 1;
770 return 0;
771}
772
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500773static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb,
774 ext4_group_t group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700775{
Theodore Ts'o8dadb192009-11-23 07:24:38 -0500776 if (!ext4_bg_has_super(sb, group))
777 return 0;
778
779 if (EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG))
780 return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
781 else
782 return EXT4_SB(sb)->s_gdb_count;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700783}
784
785/**
Mingming Cao617ba132006-10-11 01:20:53 -0700786 * ext4_bg_num_gdb - number of blocks used by the group table in group
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700787 * @sb: superblock for filesystem
788 * @group: group number to check
789 *
790 * Return the number of blocks used by the group descriptor table
791 * (primary or backup) in this group. In the future there may be a
792 * different number of descriptor blocks in each group.
793 */
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500794unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700795{
796 unsigned long first_meta_bg =
Mingming Cao617ba132006-10-11 01:20:53 -0700797 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
798 unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700799
Mingming Cao617ba132006-10-11 01:20:53 -0700800 if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) ||
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700801 metagroup < first_meta_bg)
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400802 return ext4_bg_num_gdb_nometa(sb, group);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700803
Mingming Cao617ba132006-10-11 01:20:53 -0700804 return ext4_bg_num_gdb_meta(sb,group);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700805
806}
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -0400807
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400808/*
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400809 * This function returns the number of file system metadata clusters at
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400810 * the beginning of a block group, including the reserved gdt blocks.
811 */
Eric Sandeen5f163cc2012-01-04 22:33:28 -0500812static unsigned ext4_num_base_meta_clusters(struct super_block *sb,
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400813 ext4_group_t block_group)
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400814{
815 struct ext4_sb_info *sbi = EXT4_SB(sb);
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400816 unsigned num;
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400817
818 /* Check for superblock and gdt backups in this group */
819 num = ext4_bg_has_super(sb, block_group);
820
821 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
822 block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) *
823 sbi->s_desc_per_block) {
824 if (num) {
825 num += ext4_bg_num_gdb(sb, block_group);
826 num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks);
827 }
828 } else { /* For META_BG_BLOCK_GROUPS */
829 num += ext4_bg_num_gdb(sb, block_group);
830 }
Theodore Ts'od5b8f312011-09-09 18:44:51 -0400831 return EXT4_NUM_B2C(sbi, num);
Theodore Ts'o49f7f9a2011-09-09 18:40:51 -0400832}
Eric Sandeenf86186b2011-06-28 10:01:31 -0400833/**
834 * ext4_inode_to_goal_block - return a hint for block allocation
835 * @inode: inode for block allocation
836 *
837 * Return the ideal location to start allocating blocks for a
838 * newly created inode.
839 */
840ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode)
841{
842 struct ext4_inode_info *ei = EXT4_I(inode);
843 ext4_group_t block_group;
844 ext4_grpblk_t colour;
845 int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
846 ext4_fsblk_t bg_start;
847 ext4_fsblk_t last_block;
848
849 block_group = ei->i_block_group;
850 if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
851 /*
852 * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
853 * block groups per flexgroup, reserve the first block
854 * group for directories and special files. Regular
855 * files will start at the second block group. This
856 * tends to speed up directory access and improves
857 * fsck times.
858 */
859 block_group &= ~(flex_size-1);
860 if (S_ISREG(inode->i_mode))
861 block_group++;
862 }
863 bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
864 last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
865
866 /*
867 * If we are doing delayed allocation, we don't need take
868 * colour into account.
869 */
870 if (test_opt(inode->i_sb, DELALLOC))
871 return bg_start;
872
873 if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
874 colour = (current->pid % 16) *
875 (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
876 else
877 colour = (current->pid % 16) * ((last_block - bg_start) / 16);
878 return bg_start + colour;
879}
880