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Linux/fs/ext4/balloc.c

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Diff markup

Differences between /fs/ext4/balloc.c (Version linux-6.12-rc7) and /fs/ext4/balloc.c (Version linux-4.15.18)


  1 // SPDX-License-Identifier: GPL-2.0                 1 // SPDX-License-Identifier: GPL-2.0
  2 /*                                                  2 /*
  3  *  linux/fs/ext4/balloc.c                          3  *  linux/fs/ext4/balloc.c
  4  *                                                  4  *
  5  * Copyright (C) 1992, 1993, 1994, 1995             5  * Copyright (C) 1992, 1993, 1994, 1995
  6  * Remy Card (card@masi.ibp.fr)                     6  * Remy Card (card@masi.ibp.fr)
  7  * Laboratoire MASI - Institut Blaise Pascal        7  * Laboratoire MASI - Institut Blaise Pascal
  8  * Universite Pierre et Marie Curie (Paris VI)      8  * Universite Pierre et Marie Curie (Paris VI)
  9  *                                                  9  *
 10  *  Enhanced block allocation by Stephen Tweed     10  *  Enhanced block allocation by Stephen Tweedie (sct@redhat.com), 1993
 11  *  Big-endian to little-endian byte-swapping/     11  *  Big-endian to little-endian byte-swapping/bitmaps by
 12  *        David S. Miller (davem@caip.rutgers.     12  *        David S. Miller (davem@caip.rutgers.edu), 1995
 13  */                                                13  */
 14                                                    14 
 15 #include <linux/time.h>                            15 #include <linux/time.h>
 16 #include <linux/capability.h>                      16 #include <linux/capability.h>
 17 #include <linux/fs.h>                              17 #include <linux/fs.h>
 18 #include <linux/quotaops.h>                        18 #include <linux/quotaops.h>
 19 #include <linux/buffer_head.h>                     19 #include <linux/buffer_head.h>
 20 #include "ext4.h"                                  20 #include "ext4.h"
 21 #include "ext4_jbd2.h"                             21 #include "ext4_jbd2.h"
 22 #include "mballoc.h"                               22 #include "mballoc.h"
 23                                                    23 
 24 #include <trace/events/ext4.h>                     24 #include <trace/events/ext4.h>
 25 #include <kunit/static_stub.h>                 << 
 26                                                    25 
 27 static unsigned ext4_num_base_meta_clusters(st     26 static unsigned ext4_num_base_meta_clusters(struct super_block *sb,
 28                                             ex     27                                             ext4_group_t block_group);
 29 /*                                                 28 /*
 30  * balloc.c contains the blocks allocation and     29  * balloc.c contains the blocks allocation and deallocation routines
 31  */                                                30  */
 32                                                    31 
 33 /*                                                 32 /*
 34  * Calculate block group number for a given bl     33  * Calculate block group number for a given block number
 35  */                                                34  */
 36 ext4_group_t ext4_get_group_number(struct supe     35 ext4_group_t ext4_get_group_number(struct super_block *sb,
 37                                    ext4_fsblk_     36                                    ext4_fsblk_t block)
 38 {                                                  37 {
 39         ext4_group_t group;                        38         ext4_group_t group;
 40                                                    39 
 41         if (test_opt2(sb, STD_GROUP_SIZE))         40         if (test_opt2(sb, STD_GROUP_SIZE))
 42                 group = (block -                   41                 group = (block -
 43                          le32_to_cpu(EXT4_SB(s     42                          le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) >>
 44                         (EXT4_BLOCK_SIZE_BITS(     43                         (EXT4_BLOCK_SIZE_BITS(sb) + EXT4_CLUSTER_BITS(sb) + 3);
 45         else                                       44         else
 46                 ext4_get_group_no_and_offset(s     45                 ext4_get_group_no_and_offset(sb, block, &group, NULL);
 47         return group;                              46         return group;
 48 }                                                  47 }
 49                                                    48 
 50 /*                                                 49 /*
 51  * Calculate the block group number and offset     50  * Calculate the block group number and offset into the block/cluster
 52  * allocation bitmap, given a block number         51  * allocation bitmap, given a block number
 53  */                                                52  */
 54 void ext4_get_group_no_and_offset(struct super     53 void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
 55                 ext4_group_t *blockgrpp, ext4_     54                 ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp)
 56 {                                                  55 {
 57         struct ext4_super_block *es = EXT4_SB(     56         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 58         ext4_grpblk_t offset;                      57         ext4_grpblk_t offset;
 59                                                    58 
 60         blocknr = blocknr - le32_to_cpu(es->s_     59         blocknr = blocknr - le32_to_cpu(es->s_first_data_block);
 61         offset = do_div(blocknr, EXT4_BLOCKS_P     60         offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)) >>
 62                 EXT4_SB(sb)->s_cluster_bits;       61                 EXT4_SB(sb)->s_cluster_bits;
 63         if (offsetp)                               62         if (offsetp)
 64                 *offsetp = offset;                 63                 *offsetp = offset;
 65         if (blockgrpp)                             64         if (blockgrpp)
 66                 *blockgrpp = blocknr;              65                 *blockgrpp = blocknr;
 67                                                    66 
 68 }                                                  67 }
 69                                                    68 
 70 /*                                                 69 /*
 71  * Check whether the 'block' lives within the      70  * Check whether the 'block' lives within the 'block_group'. Returns 1 if so
 72  * and 0 otherwise.                                71  * and 0 otherwise.
 73  */                                                72  */
 74 static inline int ext4_block_in_group(struct s     73 static inline int ext4_block_in_group(struct super_block *sb,
 75                                       ext4_fsb     74                                       ext4_fsblk_t block,
 76                                       ext4_gro     75                                       ext4_group_t block_group)
 77 {                                                  76 {
 78         ext4_group_t actual_group;                 77         ext4_group_t actual_group;
 79                                                    78 
 80         actual_group = ext4_get_group_number(s     79         actual_group = ext4_get_group_number(sb, block);
 81         return (actual_group == block_group) ?     80         return (actual_group == block_group) ? 1 : 0;
 82 }                                                  81 }
 83                                                    82 
 84 /*                                             !!  83 /* Return the number of clusters used for file system metadata; this
 85  * Return the number of clusters used for file << 
 86  * represents the overhead needed by the file      84  * represents the overhead needed by the file system.
 87  */                                                85  */
 88 static unsigned ext4_num_overhead_clusters(str     86 static unsigned ext4_num_overhead_clusters(struct super_block *sb,
 89                                            ext     87                                            ext4_group_t block_group,
 90                                            str     88                                            struct ext4_group_desc *gdp)
 91 {                                                  89 {
 92         unsigned base_clusters, num_clusters;  !!  90         unsigned num_clusters;
 93         int block_cluster = -1, inode_cluster; !!  91         int block_cluster = -1, inode_cluster = -1, itbl_cluster = -1, i, c;
 94         int itbl_cluster_start = -1, itbl_clus << 
 95         ext4_fsblk_t start = ext4_group_first_     92         ext4_fsblk_t start = ext4_group_first_block_no(sb, block_group);
 96         ext4_fsblk_t end = start + EXT4_BLOCKS !!  93         ext4_fsblk_t itbl_blk;
 97         ext4_fsblk_t itbl_blk_start, itbl_blk_ << 
 98         struct ext4_sb_info *sbi = EXT4_SB(sb)     94         struct ext4_sb_info *sbi = EXT4_SB(sb);
 99                                                    95 
100         /* This is the number of clusters used     96         /* This is the number of clusters used by the superblock,
101          * block group descriptors, and reserv     97          * block group descriptors, and reserved block group
102          * descriptor blocks */                    98          * descriptor blocks */
103         base_clusters = ext4_num_base_meta_clu !!  99         num_clusters = ext4_num_base_meta_clusters(sb, block_group);
104         num_clusters = base_clusters;          << 
105                                                << 
106         /*                                     << 
107          * Account and record inode table clus << 
108          * is in the block group, or inode tab << 
109          * [-1, -1] and won't overlap with blo << 
110          * accounted below.                    << 
111          */                                    << 
112         itbl_blk_start = ext4_inode_table(sb,  << 
113         itbl_blk_end = itbl_blk_start + sbi->s << 
114         if (itbl_blk_start <= end && itbl_blk_ << 
115                 itbl_blk_start = max(itbl_blk_ << 
116                 itbl_blk_end = min(itbl_blk_en << 
117                                                << 
118                 itbl_cluster_start = EXT4_B2C( << 
119                 itbl_cluster_end = EXT4_B2C(sb << 
120                                                << 
121                 num_clusters += itbl_cluster_e << 
122                 /* check if border cluster is  << 
123                 if (itbl_cluster_start == base << 
124                         num_clusters--;        << 
125         }                                      << 
126                                                   100 
127         /*                                        101         /*
128          * For the allocation bitmaps, we firs !! 102          * For the allocation bitmaps and inode table, we first need
129          * if the block is in the block group. !! 103          * to check to see if the block is in the block group.  If it
130          * to see if the cluster is already ac !! 104          * is, then check to see if the cluster is already accounted
131          * used for the base metadata cluster  !! 105          * for in the clusters used for the base metadata cluster, or
                                                   >> 106          * if we can increment the base metadata cluster to include
                                                   >> 107          * that block.  Otherwise, we will have to track the cluster
                                                   >> 108          * used for the allocation bitmap or inode table explicitly.
132          * Normally all of these blocks are co    109          * Normally all of these blocks are contiguous, so the special
133          * case handling shouldn't be necessar    110          * case handling shouldn't be necessary except for *very*
134          * unusual file system layouts.           111          * unusual file system layouts.
135          */                                       112          */
136         if (ext4_block_in_group(sb, ext4_block    113         if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) {
137                 block_cluster = EXT4_B2C(sbi,     114                 block_cluster = EXT4_B2C(sbi,
138                                          ext4_    115                                          ext4_block_bitmap(sb, gdp) - start);
139                 if (block_cluster >= base_clus !! 116                 if (block_cluster < num_clusters)
140                     (block_cluster < itbl_clus !! 117                         block_cluster = -1;
141                     block_cluster > itbl_clust !! 118                 else if (block_cluster == num_clusters) {
142                         num_clusters++;           119                         num_clusters++;
                                                   >> 120                         block_cluster = -1;
                                                   >> 121                 }
143         }                                         122         }
144                                                   123 
145         if (ext4_block_in_group(sb, ext4_inode    124         if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) {
146                 inode_cluster = EXT4_B2C(sbi,     125                 inode_cluster = EXT4_B2C(sbi,
147                                          ext4_    126                                          ext4_inode_bitmap(sb, gdp) - start);
148                 /*                             !! 127                 if (inode_cluster < num_clusters)
149                  * Additional check if inode b !! 128                         inode_cluster = -1;
150                  * block_cluster               !! 129                 else if (inode_cluster == num_clusters) {
151                  */                            !! 130                         num_clusters++;
152                 if (inode_cluster != block_clu !! 131                         inode_cluster = -1;
153                     inode_cluster >= base_clus !! 132                 }
154                     (inode_cluster < itbl_clus !! 133         }
155                     inode_cluster > itbl_clust !! 134 
                                                   >> 135         itbl_blk = ext4_inode_table(sb, gdp);
                                                   >> 136         for (i = 0; i < sbi->s_itb_per_group; i++) {
                                                   >> 137                 if (ext4_block_in_group(sb, itbl_blk + i, block_group)) {
                                                   >> 138                         c = EXT4_B2C(sbi, itbl_blk + i - start);
                                                   >> 139                         if ((c < num_clusters) || (c == inode_cluster) ||
                                                   >> 140                             (c == block_cluster) || (c == itbl_cluster))
                                                   >> 141                                 continue;
                                                   >> 142                         if (c == num_clusters) {
                                                   >> 143                                 num_clusters++;
                                                   >> 144                                 continue;
                                                   >> 145                         }
156                         num_clusters++;           146                         num_clusters++;
                                                   >> 147                         itbl_cluster = c;
                                                   >> 148                 }
157         }                                         149         }
158                                                   150 
                                                   >> 151         if (block_cluster != -1)
                                                   >> 152                 num_clusters++;
                                                   >> 153         if (inode_cluster != -1)
                                                   >> 154                 num_clusters++;
                                                   >> 155 
159         return num_clusters;                      156         return num_clusters;
160 }                                                 157 }
161                                                   158 
162 static unsigned int num_clusters_in_group(stru    159 static unsigned int num_clusters_in_group(struct super_block *sb,
163                                           ext4    160                                           ext4_group_t block_group)
164 {                                                 161 {
165         unsigned int blocks;                      162         unsigned int blocks;
166                                                   163 
167         if (block_group == ext4_get_groups_cou    164         if (block_group == ext4_get_groups_count(sb) - 1) {
168                 /*                                165                 /*
169                  * Even though mke2fs always i    166                  * Even though mke2fs always initializes the first and
170                  * last group, just in case so    167                  * last group, just in case some other tool was used,
171                  * we need to make sure we cal    168                  * we need to make sure we calculate the right free
172                  * blocks.                        169                  * blocks.
173                  */                               170                  */
174                 blocks = ext4_blocks_count(EXT    171                 blocks = ext4_blocks_count(EXT4_SB(sb)->s_es) -
175                         ext4_group_first_block    172                         ext4_group_first_block_no(sb, block_group);
176         } else                                    173         } else
177                 blocks = EXT4_BLOCKS_PER_GROUP    174                 blocks = EXT4_BLOCKS_PER_GROUP(sb);
178         return EXT4_NUM_B2C(EXT4_SB(sb), block    175         return EXT4_NUM_B2C(EXT4_SB(sb), blocks);
179 }                                                 176 }
180                                                   177 
181 /* Initializes an uninitialized block bitmap *    178 /* Initializes an uninitialized block bitmap */
182 static int ext4_init_block_bitmap(struct super    179 static int ext4_init_block_bitmap(struct super_block *sb,
183                                    struct buff    180                                    struct buffer_head *bh,
184                                    ext4_group_    181                                    ext4_group_t block_group,
185                                    struct ext4    182                                    struct ext4_group_desc *gdp)
186 {                                                 183 {
187         unsigned int bit, bit_max;                184         unsigned int bit, bit_max;
188         struct ext4_sb_info *sbi = EXT4_SB(sb)    185         struct ext4_sb_info *sbi = EXT4_SB(sb);
189         ext4_fsblk_t start, tmp;                  186         ext4_fsblk_t start, tmp;
                                                   >> 187         int flex_bg = 0;
                                                   >> 188         struct ext4_group_info *grp;
190                                                   189 
191         ASSERT(buffer_locked(bh));             !! 190         J_ASSERT_BH(bh, buffer_locked(bh));
192                                                   191 
                                                   >> 192         /* If checksum is bad mark all blocks used to prevent allocation
                                                   >> 193          * essentially implementing a per-group read-only flag. */
193         if (!ext4_group_desc_csum_verify(sb, b    194         if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
194                 ext4_mark_group_bitmap_corrupt !! 195                 grp = ext4_get_group_info(sb, block_group);
195                                         EXT4_G !! 196                 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
196                                         EXT4_G !! 197                         percpu_counter_sub(&sbi->s_freeclusters_counter,
                                                   >> 198                                            grp->bb_free);
                                                   >> 199                 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
                                                   >> 200                 if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
                                                   >> 201                         int count;
                                                   >> 202                         count = ext4_free_inodes_count(sb, gdp);
                                                   >> 203                         percpu_counter_sub(&sbi->s_freeinodes_counter,
                                                   >> 204                                            count);
                                                   >> 205                 }
                                                   >> 206                 set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state);
197                 return -EFSBADCRC;                207                 return -EFSBADCRC;
198         }                                         208         }
199         memset(bh->b_data, 0, sb->s_blocksize)    209         memset(bh->b_data, 0, sb->s_blocksize);
200                                                   210 
201         bit_max = ext4_num_base_meta_clusters(    211         bit_max = ext4_num_base_meta_clusters(sb, block_group);
202         if ((bit_max >> 3) >= bh->b_size)         212         if ((bit_max >> 3) >= bh->b_size)
203                 return -EFSCORRUPTED;             213                 return -EFSCORRUPTED;
204                                                   214 
205         for (bit = 0; bit < bit_max; bit++)       215         for (bit = 0; bit < bit_max; bit++)
206                 ext4_set_bit(bit, bh->b_data);    216                 ext4_set_bit(bit, bh->b_data);
207                                                   217 
208         start = ext4_group_first_block_no(sb,     218         start = ext4_group_first_block_no(sb, block_group);
209                                                   219 
                                                   >> 220         if (ext4_has_feature_flex_bg(sb))
                                                   >> 221                 flex_bg = 1;
                                                   >> 222 
210         /* Set bits for block and inode bitmap    223         /* Set bits for block and inode bitmaps, and inode table */
211         tmp = ext4_block_bitmap(sb, gdp);         224         tmp = ext4_block_bitmap(sb, gdp);
212         if (ext4_block_in_group(sb, tmp, block !! 225         if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
213                 ext4_set_bit(EXT4_B2C(sbi, tmp    226                 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
214                                                   227 
215         tmp = ext4_inode_bitmap(sb, gdp);         228         tmp = ext4_inode_bitmap(sb, gdp);
216         if (ext4_block_in_group(sb, tmp, block !! 229         if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
217                 ext4_set_bit(EXT4_B2C(sbi, tmp    230                 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
218                                                   231 
219         tmp = ext4_inode_table(sb, gdp);          232         tmp = ext4_inode_table(sb, gdp);
220         for (; tmp < ext4_inode_table(sb, gdp)    233         for (; tmp < ext4_inode_table(sb, gdp) +
221                      sbi->s_itb_per_group; tmp    234                      sbi->s_itb_per_group; tmp++) {
222                 if (ext4_block_in_group(sb, tm !! 235                 if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
223                         ext4_set_bit(EXT4_B2C(    236                         ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
224         }                                         237         }
225                                                   238 
226         /*                                        239         /*
227          * Also if the number of blocks within    240          * Also if the number of blocks within the group is less than
228          * the blocksize * 8 ( which is the si    241          * the blocksize * 8 ( which is the size of bitmap ), set rest
229          * of the block bitmap to 1               242          * of the block bitmap to 1
230          */                                       243          */
231         ext4_mark_bitmap_end(num_clusters_in_g    244         ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group),
232                              sb->s_blocksize *    245                              sb->s_blocksize * 8, bh->b_data);
                                                   >> 246         ext4_block_bitmap_csum_set(sb, block_group, gdp, bh);
                                                   >> 247         ext4_group_desc_csum_set(sb, block_group, gdp);
233         return 0;                                 248         return 0;
234 }                                                 249 }
235                                                   250 
236 /* Return the number of free blocks in a block    251 /* Return the number of free blocks in a block group.  It is used when
237  * the block bitmap is uninitialized, so we ca    252  * the block bitmap is uninitialized, so we can't just count the bits
238  * in the bitmap. */                              253  * in the bitmap. */
239 unsigned ext4_free_clusters_after_init(struct     254 unsigned ext4_free_clusters_after_init(struct super_block *sb,
240                                        ext4_gr    255                                        ext4_group_t block_group,
241                                        struct     256                                        struct ext4_group_desc *gdp)
242 {                                                 257 {
243         return num_clusters_in_group(sb, block !! 258         return num_clusters_in_group(sb, block_group) - 
244                 ext4_num_overhead_clusters(sb,    259                 ext4_num_overhead_clusters(sb, block_group, gdp);
245 }                                                 260 }
246                                                   261 
247 /*                                                262 /*
248  * The free blocks are managed by bitmaps.  A     263  * The free blocks are managed by bitmaps.  A file system contains several
249  * blocks groups.  Each group contains 1 bitma    264  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
250  * block for inodes, N blocks for the inode ta    265  * block for inodes, N blocks for the inode table and data blocks.
251  *                                                266  *
252  * The file system contains group descriptors     267  * The file system contains group descriptors which are located after the
253  * super block.  Each descriptor contains the     268  * super block.  Each descriptor contains the number of the bitmap block and
254  * the free blocks count in the block.  The de    269  * the free blocks count in the block.  The descriptors are loaded in memory
255  * when a file system is mounted (see ext4_fil    270  * when a file system is mounted (see ext4_fill_super).
256  */                                               271  */
257                                                   272 
258 /**                                               273 /**
259  * ext4_get_group_desc() -- load group descrip    274  * ext4_get_group_desc() -- load group descriptor from disk
260  * @sb:                 super block               275  * @sb:                 super block
261  * @block_group:        given block group         276  * @block_group:        given block group
262  * @bh:                 pointer to the buffer     277  * @bh:                 pointer to the buffer head to store the block
263  *                      group descriptor          278  *                      group descriptor
264  */                                               279  */
265 struct ext4_group_desc * ext4_get_group_desc(s    280 struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb,
266                                              e    281                                              ext4_group_t block_group,
267                                              s    282                                              struct buffer_head **bh)
268 {                                                 283 {
269         unsigned int group_desc;                  284         unsigned int group_desc;
270         unsigned int offset;                      285         unsigned int offset;
271         ext4_group_t ngroups = ext4_get_groups    286         ext4_group_t ngroups = ext4_get_groups_count(sb);
272         struct ext4_group_desc *desc;             287         struct ext4_group_desc *desc;
273         struct ext4_sb_info *sbi = EXT4_SB(sb)    288         struct ext4_sb_info *sbi = EXT4_SB(sb);
274         struct buffer_head *bh_p;              << 
275                                                << 
276         KUNIT_STATIC_STUB_REDIRECT(ext4_get_gr << 
277                                    sb, block_g << 
278                                                   289 
279         if (block_group >= ngroups) {             290         if (block_group >= ngroups) {
280                 ext4_error(sb, "block_group >=    291                 ext4_error(sb, "block_group >= groups_count - block_group = %u,"
281                            " groups_count = %u    292                            " groups_count = %u", block_group, ngroups);
282                                                   293 
283                 return NULL;                      294                 return NULL;
284         }                                         295         }
285                                                   296 
286         group_desc = block_group >> EXT4_DESC_    297         group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
287         offset = block_group & (EXT4_DESC_PER_    298         offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
288         bh_p = sbi_array_rcu_deref(sbi, s_grou !! 299         if (!sbi->s_group_desc[group_desc]) {
289         /*                                     << 
290          * sbi_array_rcu_deref returns with rc << 
291          * the pointer being dereferenced won' << 
292          * looking at the usage in add_new_gdb << 
293          * just the pointer, and so it remains << 
294          */                                    << 
295         if (!bh_p) {                           << 
296                 ext4_error(sb, "Group descript    300                 ext4_error(sb, "Group descriptor not loaded - "
297                            "block_group = %u,     301                            "block_group = %u, group_desc = %u, desc = %u",
298                            block_group, group_    302                            block_group, group_desc, offset);
299                 return NULL;                      303                 return NULL;
300         }                                         304         }
301                                                   305 
302         desc = (struct ext4_group_desc *)(        306         desc = (struct ext4_group_desc *)(
303                 (__u8 *)bh_p->b_data +         !! 307                 (__u8 *)sbi->s_group_desc[group_desc]->b_data +
304                 offset * EXT4_DESC_SIZE(sb));     308                 offset * EXT4_DESC_SIZE(sb));
305         if (bh)                                   309         if (bh)
306                 *bh = bh_p;                    !! 310                 *bh = sbi->s_group_desc[group_desc];
307         return desc;                              311         return desc;
308 }                                                 312 }
309                                                   313 
310 static ext4_fsblk_t ext4_valid_block_bitmap_pa << 
311                                                << 
312                                                << 
313 {                                              << 
314         ext4_grpblk_t next_zero_bit;           << 
315         unsigned long bitmap_size = sb->s_bloc << 
316         unsigned int offset = num_clusters_in_ << 
317                                                << 
318         if (bitmap_size <= offset)             << 
319                 return 0;                      << 
320                                                << 
321         next_zero_bit = ext4_find_next_zero_bi << 
322                                                << 
323         return (next_zero_bit < bitmap_size ?  << 
324 }                                              << 
325                                                << 
326 struct ext4_group_info *ext4_get_group_info(st << 
327                                             ex << 
328 {                                              << 
329         struct ext4_group_info **grp_info;     << 
330         long indexv, indexh;                   << 
331                                                << 
332         if (unlikely(group >= EXT4_SB(sb)->s_g << 
333                 return NULL;                   << 
334         indexv = group >> (EXT4_DESC_PER_BLOCK << 
335         indexh = group & ((EXT4_DESC_PER_BLOCK << 
336         grp_info = sbi_array_rcu_deref(EXT4_SB << 
337         return grp_info[indexh];               << 
338 }                                              << 
339                                                << 
340 /*                                                314 /*
341  * Return the block number which was discovere    315  * Return the block number which was discovered to be invalid, or 0 if
342  * the block bitmap is valid.                     316  * the block bitmap is valid.
343  */                                               317  */
344 static ext4_fsblk_t ext4_valid_block_bitmap(st    318 static ext4_fsblk_t ext4_valid_block_bitmap(struct super_block *sb,
345                                             st    319                                             struct ext4_group_desc *desc,
346                                             ex    320                                             ext4_group_t block_group,
347                                             st    321                                             struct buffer_head *bh)
348 {                                                 322 {
349         struct ext4_sb_info *sbi = EXT4_SB(sb)    323         struct ext4_sb_info *sbi = EXT4_SB(sb);
350         ext4_grpblk_t offset;                     324         ext4_grpblk_t offset;
351         ext4_grpblk_t next_zero_bit;              325         ext4_grpblk_t next_zero_bit;
352         ext4_grpblk_t max_bit = EXT4_CLUSTERS_ << 
353         ext4_fsblk_t blk;                         326         ext4_fsblk_t blk;
354         ext4_fsblk_t group_first_block;           327         ext4_fsblk_t group_first_block;
355                                                   328 
356         if (ext4_has_feature_flex_bg(sb)) {       329         if (ext4_has_feature_flex_bg(sb)) {
357                 /* with FLEX_BG, the inode/blo    330                 /* with FLEX_BG, the inode/block bitmaps and itable
358                  * blocks may not be in the gr    331                  * blocks may not be in the group at all
359                  * so the bitmap validation wi    332                  * so the bitmap validation will be skipped for those groups
360                  * or it has to also read the     333                  * or it has to also read the block group where the bitmaps
361                  * are located to verify they     334                  * are located to verify they are set.
362                  */                               335                  */
363                 return 0;                         336                 return 0;
364         }                                         337         }
365         group_first_block = ext4_group_first_b    338         group_first_block = ext4_group_first_block_no(sb, block_group);
366                                                   339 
367         /* check whether block bitmap block nu    340         /* check whether block bitmap block number is set */
368         blk = ext4_block_bitmap(sb, desc);        341         blk = ext4_block_bitmap(sb, desc);
369         offset = blk - group_first_block;         342         offset = blk - group_first_block;
370         if (offset < 0 || EXT4_B2C(sbi, offset !! 343         if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
371             !ext4_test_bit(EXT4_B2C(sbi, offse << 
372                 /* bad block bitmap */            344                 /* bad block bitmap */
373                 return blk;                       345                 return blk;
374                                                   346 
375         /* check whether the inode bitmap bloc    347         /* check whether the inode bitmap block number is set */
376         blk = ext4_inode_bitmap(sb, desc);        348         blk = ext4_inode_bitmap(sb, desc);
377         offset = blk - group_first_block;         349         offset = blk - group_first_block;
378         if (offset < 0 || EXT4_B2C(sbi, offset !! 350         if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
379             !ext4_test_bit(EXT4_B2C(sbi, offse << 
380                 /* bad block bitmap */            351                 /* bad block bitmap */
381                 return blk;                       352                 return blk;
382                                                   353 
383         /* check whether the inode table block    354         /* check whether the inode table block number is set */
384         blk = ext4_inode_table(sb, desc);         355         blk = ext4_inode_table(sb, desc);
385         offset = blk - group_first_block;         356         offset = blk - group_first_block;
386         if (offset < 0 || EXT4_B2C(sbi, offset << 
387             EXT4_B2C(sbi, offset + sbi->s_itb_ << 
388                 return blk;                    << 
389         next_zero_bit = ext4_find_next_zero_bi    357         next_zero_bit = ext4_find_next_zero_bit(bh->b_data,
390                         EXT4_B2C(sbi, offset + !! 358                         EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group),
391                         EXT4_B2C(sbi, offset))    359                         EXT4_B2C(sbi, offset));
392         if (next_zero_bit <                       360         if (next_zero_bit <
393             EXT4_B2C(sbi, offset + sbi->s_itb_ !! 361             EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group))
394                 /* bad bitmap for inode tables    362                 /* bad bitmap for inode tables */
395                 return blk;                       363                 return blk;
396         return 0;                                 364         return 0;
397 }                                                 365 }
398                                                   366 
399 static int ext4_validate_block_bitmap(struct s    367 static int ext4_validate_block_bitmap(struct super_block *sb,
400                                       struct e    368                                       struct ext4_group_desc *desc,
401                                       ext4_gro    369                                       ext4_group_t block_group,
402                                       struct b    370                                       struct buffer_head *bh)
403 {                                                 371 {
404         ext4_fsblk_t    blk;                      372         ext4_fsblk_t    blk;
405         struct ext4_group_info *grp;           !! 373         struct ext4_group_info *grp = ext4_get_group_info(sb, block_group);
406                                                !! 374         struct ext4_sb_info *sbi = EXT4_SB(sb);
407         if (EXT4_SB(sb)->s_mount_state & EXT4_ << 
408                 return 0;                      << 
409                                                << 
410         grp = ext4_get_group_info(sb, block_gr << 
411                                                   375 
412         if (buffer_verified(bh))                  376         if (buffer_verified(bh))
413                 return 0;                         377                 return 0;
414         if (!grp || EXT4_MB_GRP_BBITMAP_CORRUP !! 378         if (EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
415                 return -EFSCORRUPTED;             379                 return -EFSCORRUPTED;
416                                                   380 
417         ext4_lock_group(sb, block_group);         381         ext4_lock_group(sb, block_group);
418         if (buffer_verified(bh))               !! 382         if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group,
419                 goto verified;                 !! 383                         desc, bh))) {
420         if (unlikely(!ext4_block_bitmap_csum_v << 
421                      ext4_simulate_fail(sb, EX << 
422                 ext4_unlock_group(sb, block_gr    384                 ext4_unlock_group(sb, block_group);
423                 ext4_error(sb, "bg %u: bad blo    385                 ext4_error(sb, "bg %u: bad block bitmap checksum", block_group);
424                 ext4_mark_group_bitmap_corrupt !! 386                 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
425                                         EXT4_G !! 387                         percpu_counter_sub(&sbi->s_freeclusters_counter,
                                                   >> 388                                            grp->bb_free);
                                                   >> 389                 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
426                 return -EFSBADCRC;                390                 return -EFSBADCRC;
427         }                                         391         }
428         blk = ext4_valid_block_bitmap(sb, desc    392         blk = ext4_valid_block_bitmap(sb, desc, block_group, bh);
429         if (unlikely(blk != 0)) {                 393         if (unlikely(blk != 0)) {
430                 ext4_unlock_group(sb, block_gr    394                 ext4_unlock_group(sb, block_group);
431                 ext4_error(sb, "bg %u: block %    395                 ext4_error(sb, "bg %u: block %llu: invalid block bitmap",
432                            block_group, blk);     396                            block_group, blk);
433                 ext4_mark_group_bitmap_corrupt !! 397                 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
434                                         EXT4_G !! 398                         percpu_counter_sub(&sbi->s_freeclusters_counter,
435                 return -EFSCORRUPTED;          !! 399                                            grp->bb_free);
436         }                                      !! 400                 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state);
437         blk = ext4_valid_block_bitmap_padding( << 
438         if (unlikely(blk != 0)) {              << 
439                 ext4_unlock_group(sb, block_gr << 
440                 ext4_error(sb, "bg %u: block % << 
441                            block_group, blk);  << 
442                 ext4_mark_group_bitmap_corrupt << 
443                                                << 
444                 return -EFSCORRUPTED;             401                 return -EFSCORRUPTED;
445         }                                         402         }
446         set_buffer_verified(bh);                  403         set_buffer_verified(bh);
447 verified:                                      << 
448         ext4_unlock_group(sb, block_group);       404         ext4_unlock_group(sb, block_group);
449         return 0;                                 405         return 0;
450 }                                                 406 }
451                                                   407 
452 /**                                               408 /**
453  * ext4_read_block_bitmap_nowait()                409  * ext4_read_block_bitmap_nowait()
454  * @sb:                 super block               410  * @sb:                 super block
455  * @block_group:        given block group         411  * @block_group:        given block group
456  * @ignore_locked:      ignore locked buffers  << 
457  *                                                412  *
458  * Read the bitmap for a given block_group,and    413  * Read the bitmap for a given block_group,and validate the
459  * bits for block/inode/inode tables are set i    414  * bits for block/inode/inode tables are set in the bitmaps
460  *                                                415  *
461  * Return buffer_head on success or an ERR_PTR !! 416  * Return buffer_head on success or NULL in case of failure.
462  */                                               417  */
463 struct buffer_head *                              418 struct buffer_head *
464 ext4_read_block_bitmap_nowait(struct super_blo !! 419 ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group)
465                               bool ignore_lock << 
466 {                                                 420 {
467         struct ext4_group_desc *desc;             421         struct ext4_group_desc *desc;
468         struct ext4_sb_info *sbi = EXT4_SB(sb) << 
469         struct buffer_head *bh;                   422         struct buffer_head *bh;
470         ext4_fsblk_t bitmap_blk;                  423         ext4_fsblk_t bitmap_blk;
471         int err;                                  424         int err;
472                                                   425 
473         KUNIT_STATIC_STUB_REDIRECT(ext4_read_b << 
474                                    sb, block_g << 
475                                                << 
476         desc = ext4_get_group_desc(sb, block_g    426         desc = ext4_get_group_desc(sb, block_group, NULL);
477         if (!desc)                                427         if (!desc)
478                 return ERR_PTR(-EFSCORRUPTED);    428                 return ERR_PTR(-EFSCORRUPTED);
479         bitmap_blk = ext4_block_bitmap(sb, des    429         bitmap_blk = ext4_block_bitmap(sb, desc);
480         if ((bitmap_blk <= le32_to_cpu(sbi->s_ << 
481             (bitmap_blk >= ext4_blocks_count(s << 
482                 ext4_error(sb, "Invalid block  << 
483                            "block_group %u", b << 
484                 ext4_mark_group_bitmap_corrupt << 
485                                         EXT4_G << 
486                 return ERR_PTR(-EFSCORRUPTED); << 
487         }                                      << 
488         bh = sb_getblk(sb, bitmap_blk);           430         bh = sb_getblk(sb, bitmap_blk);
489         if (unlikely(!bh)) {                      431         if (unlikely(!bh)) {
490                 ext4_warning(sb, "Cannot get b !! 432                 ext4_error(sb, "Cannot get buffer for block bitmap - "
491                              "block_group = %u !! 433                            "block_group = %u, block_bitmap = %llu",
492                              block_group, bitm !! 434                            block_group, bitmap_blk);
493                 return ERR_PTR(-ENOMEM);          435                 return ERR_PTR(-ENOMEM);
494         }                                         436         }
495                                                   437 
496         if (ignore_locked && buffer_locked(bh) << 
497                 /* buffer under IO already, re << 
498                 put_bh(bh);                    << 
499                 return NULL;                   << 
500         }                                      << 
501                                                << 
502         if (bitmap_uptodate(bh))                  438         if (bitmap_uptodate(bh))
503                 goto verify;                      439                 goto verify;
504                                                   440 
505         lock_buffer(bh);                          441         lock_buffer(bh);
506         if (bitmap_uptodate(bh)) {                442         if (bitmap_uptodate(bh)) {
507                 unlock_buffer(bh);                443                 unlock_buffer(bh);
508                 goto verify;                      444                 goto verify;
509         }                                         445         }
510         ext4_lock_group(sb, block_group);         446         ext4_lock_group(sb, block_group);
511         if (ext4_has_group_desc_csum(sb) &&    !! 447         if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
512             (desc->bg_flags & cpu_to_le16(EXT4 << 
513                 if (block_group == 0) {        << 
514                         ext4_unlock_group(sb,  << 
515                         unlock_buffer(bh);     << 
516                         ext4_error(sb, "Block  << 
517                                    "uninitiali << 
518                         err = -EFSCORRUPTED;   << 
519                         goto out;              << 
520                 }                              << 
521                 err = ext4_init_block_bitmap(s    448                 err = ext4_init_block_bitmap(sb, bh, block_group, desc);
                                                   >> 449                 set_bitmap_uptodate(bh);
                                                   >> 450                 set_buffer_uptodate(bh);
                                                   >> 451                 ext4_unlock_group(sb, block_group);
                                                   >> 452                 unlock_buffer(bh);
522                 if (err) {                        453                 if (err) {
523                         ext4_unlock_group(sb,  << 
524                         unlock_buffer(bh);     << 
525                         ext4_error(sb, "Failed    454                         ext4_error(sb, "Failed to init block bitmap for group "
526                                    "%u: %d", b    455                                    "%u: %d", block_group, err);
527                         goto out;                 456                         goto out;
528                 }                                 457                 }
529                 set_bitmap_uptodate(bh);       !! 458                 goto verify;
530                 set_buffer_uptodate(bh);       << 
531                 set_buffer_verified(bh);       << 
532                 ext4_unlock_group(sb, block_gr << 
533                 unlock_buffer(bh);             << 
534                 return bh;                     << 
535         }                                         459         }
536         ext4_unlock_group(sb, block_group);       460         ext4_unlock_group(sb, block_group);
537         if (buffer_uptodate(bh)) {                461         if (buffer_uptodate(bh)) {
538                 /*                                462                 /*
539                  * if not uninit if bh is upto    463                  * if not uninit if bh is uptodate,
540                  * bitmap is also uptodate        464                  * bitmap is also uptodate
541                  */                               465                  */
542                 set_bitmap_uptodate(bh);          466                 set_bitmap_uptodate(bh);
543                 unlock_buffer(bh);                467                 unlock_buffer(bh);
544                 goto verify;                      468                 goto verify;
545         }                                         469         }
546         /*                                        470         /*
547          * submit the buffer_head for reading     471          * submit the buffer_head for reading
548          */                                       472          */
549         set_buffer_new(bh);                       473         set_buffer_new(bh);
550         trace_ext4_read_block_bitmap_load(sb,  !! 474         trace_ext4_read_block_bitmap_load(sb, block_group);
551         ext4_read_bh_nowait(bh, REQ_META | REQ !! 475         bh->b_end_io = ext4_end_bitmap_read;
552                             (ignore_locked ? R !! 476         get_bh(bh);
553                             ext4_end_bitmap_re !! 477         submit_bh(REQ_OP_READ, REQ_META | REQ_PRIO, bh);
554         return bh;                                478         return bh;
555 verify:                                           479 verify:
556         err = ext4_validate_block_bitmap(sb, d    480         err = ext4_validate_block_bitmap(sb, desc, block_group, bh);
557         if (err)                                  481         if (err)
558                 goto out;                         482                 goto out;
559         return bh;                                483         return bh;
560 out:                                              484 out:
561         put_bh(bh);                               485         put_bh(bh);
562         return ERR_PTR(err);                      486         return ERR_PTR(err);
563 }                                                 487 }
564                                                   488 
565 /* Returns 0 on success, -errno on error */    !! 489 /* Returns 0 on success, 1 on error */
566 int ext4_wait_block_bitmap(struct super_block     490 int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group,
567                            struct buffer_head     491                            struct buffer_head *bh)
568 {                                                 492 {
569         struct ext4_group_desc *desc;             493         struct ext4_group_desc *desc;
570                                                   494 
571         KUNIT_STATIC_STUB_REDIRECT(ext4_wait_b << 
572                                    sb, block_g << 
573                                                << 
574         if (!buffer_new(bh))                      495         if (!buffer_new(bh))
575                 return 0;                         496                 return 0;
576         desc = ext4_get_group_desc(sb, block_g    497         desc = ext4_get_group_desc(sb, block_group, NULL);
577         if (!desc)                                498         if (!desc)
578                 return -EFSCORRUPTED;             499                 return -EFSCORRUPTED;
579         wait_on_buffer(bh);                       500         wait_on_buffer(bh);
580         ext4_simulate_fail_bh(sb, bh, EXT4_SIM << 
581         if (!buffer_uptodate(bh)) {               501         if (!buffer_uptodate(bh)) {
582                 ext4_error_err(sb, EIO, "Canno !! 502                 ext4_error(sb, "Cannot read block bitmap - "
583                                "block_group =  !! 503                            "block_group = %u, block_bitmap = %llu",
584                                block_group, (u !! 504                            block_group, (unsigned long long) bh->b_blocknr);
585                 ext4_mark_group_bitmap_corrupt << 
586                                         EXT4_G << 
587                 return -EIO;                      505                 return -EIO;
588         }                                         506         }
589         clear_buffer_new(bh);                     507         clear_buffer_new(bh);
590         /* Panic or remount fs read-only if bl    508         /* Panic or remount fs read-only if block bitmap is invalid */
591         return ext4_validate_block_bitmap(sb,     509         return ext4_validate_block_bitmap(sb, desc, block_group, bh);
592 }                                                 510 }
593                                                   511 
594 struct buffer_head *                              512 struct buffer_head *
595 ext4_read_block_bitmap(struct super_block *sb,    513 ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
596 {                                                 514 {
597         struct buffer_head *bh;                   515         struct buffer_head *bh;
598         int err;                                  516         int err;
599                                                   517 
600         bh = ext4_read_block_bitmap_nowait(sb, !! 518         bh = ext4_read_block_bitmap_nowait(sb, block_group);
601         if (IS_ERR(bh))                           519         if (IS_ERR(bh))
602                 return bh;                        520                 return bh;
603         err = ext4_wait_block_bitmap(sb, block    521         err = ext4_wait_block_bitmap(sb, block_group, bh);
604         if (err) {                                522         if (err) {
605                 put_bh(bh);                       523                 put_bh(bh);
606                 return ERR_PTR(err);              524                 return ERR_PTR(err);
607         }                                         525         }
608         return bh;                                526         return bh;
609 }                                                 527 }
610                                                   528 
611 /**                                               529 /**
612  * ext4_has_free_clusters()                       530  * ext4_has_free_clusters()
613  * @sbi:        in-core super block structure.    531  * @sbi:        in-core super block structure.
614  * @nclusters:  number of needed blocks           532  * @nclusters:  number of needed blocks
615  * @flags:      flags from ext4_mb_new_blocks(    533  * @flags:      flags from ext4_mb_new_blocks()
616  *                                                534  *
617  * Check if filesystem has nclusters free & av    535  * Check if filesystem has nclusters free & available for allocation.
618  * On success return 1, return 0 on failure.      536  * On success return 1, return 0 on failure.
619  */                                               537  */
620 static int ext4_has_free_clusters(struct ext4_    538 static int ext4_has_free_clusters(struct ext4_sb_info *sbi,
621                                   s64 ncluster    539                                   s64 nclusters, unsigned int flags)
622 {                                                 540 {
623         s64 free_clusters, dirty_clusters, rsv    541         s64 free_clusters, dirty_clusters, rsv, resv_clusters;
624         struct percpu_counter *fcc = &sbi->s_f    542         struct percpu_counter *fcc = &sbi->s_freeclusters_counter;
625         struct percpu_counter *dcc = &sbi->s_d    543         struct percpu_counter *dcc = &sbi->s_dirtyclusters_counter;
626                                                   544 
627         free_clusters  = percpu_counter_read_p    545         free_clusters  = percpu_counter_read_positive(fcc);
628         dirty_clusters = percpu_counter_read_p    546         dirty_clusters = percpu_counter_read_positive(dcc);
629         resv_clusters = atomic64_read(&sbi->s_    547         resv_clusters = atomic64_read(&sbi->s_resv_clusters);
630                                                   548 
631         /*                                        549         /*
632          * r_blocks_count should always be mul    550          * r_blocks_count should always be multiple of the cluster ratio so
633          * we are safe to do a plane bit shift    551          * we are safe to do a plane bit shift only.
634          */                                       552          */
635         rsv = (ext4_r_blocks_count(sbi->s_es)     553         rsv = (ext4_r_blocks_count(sbi->s_es) >> sbi->s_cluster_bits) +
636               resv_clusters;                      554               resv_clusters;
637                                                   555 
638         if (free_clusters - (nclusters + rsv +    556         if (free_clusters - (nclusters + rsv + dirty_clusters) <
639                                         EXT4_F    557                                         EXT4_FREECLUSTERS_WATERMARK) {
640                 free_clusters  = percpu_counte    558                 free_clusters  = percpu_counter_sum_positive(fcc);
641                 dirty_clusters = percpu_counte    559                 dirty_clusters = percpu_counter_sum_positive(dcc);
642         }                                         560         }
643         /* Check whether we have space after a    561         /* Check whether we have space after accounting for current
644          * dirty clusters & root reserved clus    562          * dirty clusters & root reserved clusters.
645          */                                       563          */
646         if (free_clusters >= (rsv + nclusters     564         if (free_clusters >= (rsv + nclusters + dirty_clusters))
647                 return 1;                         565                 return 1;
648                                                   566 
649         /* Hm, nope.  Are (enough) root reserv    567         /* Hm, nope.  Are (enough) root reserved clusters available? */
650         if (uid_eq(sbi->s_resuid, current_fsui    568         if (uid_eq(sbi->s_resuid, current_fsuid()) ||
651             (!gid_eq(sbi->s_resgid, GLOBAL_ROO    569             (!gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) && in_group_p(sbi->s_resgid)) ||
652             capable(CAP_SYS_RESOURCE) ||          570             capable(CAP_SYS_RESOURCE) ||
653             (flags & EXT4_MB_USE_ROOT_BLOCKS))    571             (flags & EXT4_MB_USE_ROOT_BLOCKS)) {
654                                                   572 
655                 if (free_clusters >= (ncluster    573                 if (free_clusters >= (nclusters + dirty_clusters +
656                                       resv_clu    574                                       resv_clusters))
657                         return 1;                 575                         return 1;
658         }                                         576         }
659         /* No free blocks. Let's see if we can    577         /* No free blocks. Let's see if we can dip into reserved pool */
660         if (flags & EXT4_MB_USE_RESERVED) {       578         if (flags & EXT4_MB_USE_RESERVED) {
661                 if (free_clusters >= (ncluster    579                 if (free_clusters >= (nclusters + dirty_clusters))
662                         return 1;                 580                         return 1;
663         }                                         581         }
664                                                   582 
665         return 0;                                 583         return 0;
666 }                                                 584 }
667                                                   585 
668 int ext4_claim_free_clusters(struct ext4_sb_in    586 int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
669                              s64 nclusters, un    587                              s64 nclusters, unsigned int flags)
670 {                                                 588 {
671         if (ext4_has_free_clusters(sbi, nclust    589         if (ext4_has_free_clusters(sbi, nclusters, flags)) {
672                 percpu_counter_add(&sbi->s_dir    590                 percpu_counter_add(&sbi->s_dirtyclusters_counter, nclusters);
673                 return 0;                         591                 return 0;
674         } else                                    592         } else
675                 return -ENOSPC;                   593                 return -ENOSPC;
676 }                                                 594 }
677                                                   595 
678 /**                                               596 /**
679  * ext4_should_retry_alloc() - check if a bloc !! 597  * ext4_should_retry_alloc()
680  * @sb:                 superblock             !! 598  * @sb:                 super block
681  * @retries:            number of retry attemp !! 599  * @retries             number of attemps has been made
682  *                                             !! 600  *
683  * ext4_should_retry_alloc() is called when EN !! 601  * ext4_should_retry_alloc() is called when ENOSPC is returned, and if
684  * attempting to allocate blocks.  If there's  !! 602  * it is profitable to retry the operation, this function will wait
685  * journal transaction might free some space a !! 603  * for the current or committing transaction to complete, and then
686  * succeed, this function will wait for the cu !! 604  * return TRUE.  We will only retry once.
687  * to complete and then return TRUE.           << 
688  */                                               605  */
689 int ext4_should_retry_alloc(struct super_block    606 int ext4_should_retry_alloc(struct super_block *sb, int *retries)
690 {                                                 607 {
691         struct ext4_sb_info *sbi = EXT4_SB(sb) !! 608         if (!ext4_has_free_clusters(EXT4_SB(sb), 1, 0) ||
692                                                !! 609             (*retries)++ > 1 ||
693         if (!sbi->s_journal)                   !! 610             !EXT4_SB(sb)->s_journal)
694                 return 0;                         611                 return 0;
695                                                   612 
696         if (++(*retries) > 3) {                << 
697                 percpu_counter_inc(&sbi->s_sra << 
698                 return 0;                      << 
699         }                                      << 
700                                                << 
701         /*                                     << 
702          * if there's no indication that block << 
703          * possible we just missed a transacti << 
704          */                                    << 
705         smp_mb();                                 613         smp_mb();
706         if (sbi->s_mb_free_pending == 0) {     !! 614         if (EXT4_SB(sb)->s_mb_free_pending == 0)
707                 if (test_opt(sb, DISCARD)) {   !! 615                 return 0;
708                         atomic_inc(&sbi->s_ret << 
709                         flush_work(&sbi->s_dis << 
710                         atomic_dec(&sbi->s_ret << 
711                 }                              << 
712                 return ext4_has_free_clusters( << 
713         }                                      << 
714                                                   616 
715         /*                                     !! 617         jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
716          * it's possible we've just missed a t !! 618         jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal);
717          * so ignore the returned status       << 
718          */                                    << 
719         ext4_debug("%s: retrying operation aft << 
720         (void) jbd2_journal_force_commit_neste << 
721         return 1;                                 619         return 1;
722 }                                                 620 }
723                                                   621 
724 /*                                                622 /*
725  * ext4_new_meta_blocks() -- allocate block fo    623  * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks
726  *                                                624  *
727  * @handle:             handle to this transac    625  * @handle:             handle to this transaction
728  * @inode:              file inode                626  * @inode:              file inode
729  * @goal:               given target block(fil    627  * @goal:               given target block(filesystem wide)
730  * @count:              pointer to total numbe    628  * @count:              pointer to total number of clusters needed
731  * @errp:               error code                629  * @errp:               error code
732  *                                                630  *
733  * Return 1st allocated block number on succes    631  * Return 1st allocated block number on success, *count stores total account
734  * error stores in errp pointer                   632  * error stores in errp pointer
735  */                                               633  */
736 ext4_fsblk_t ext4_new_meta_blocks(handle_t *ha    634 ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
737                                   ext4_fsblk_t    635                                   ext4_fsblk_t goal, unsigned int flags,
738                                   unsigned lon    636                                   unsigned long *count, int *errp)
739 {                                                 637 {
740         struct ext4_allocation_request ar;        638         struct ext4_allocation_request ar;
741         ext4_fsblk_t ret;                         639         ext4_fsblk_t ret;
742                                                   640 
743         memset(&ar, 0, sizeof(ar));               641         memset(&ar, 0, sizeof(ar));
744         /* Fill with neighbour allocated block    642         /* Fill with neighbour allocated blocks */
745         ar.inode = inode;                         643         ar.inode = inode;
746         ar.goal = goal;                           644         ar.goal = goal;
747         ar.len = count ? *count : 1;              645         ar.len = count ? *count : 1;
748         ar.flags = flags;                         646         ar.flags = flags;
749                                                   647 
750         ret = ext4_mb_new_blocks(handle, &ar,     648         ret = ext4_mb_new_blocks(handle, &ar, errp);
751         if (count)                                649         if (count)
752                 *count = ar.len;                  650                 *count = ar.len;
753         /*                                        651         /*
754          * Account for the allocated meta bloc    652          * Account for the allocated meta blocks.  We will never
755          * fail EDQUOT for metdata, but we do     653          * fail EDQUOT for metdata, but we do account for it.
756          */                                       654          */
757         if (!(*errp) && (flags & EXT4_MB_DELAL    655         if (!(*errp) && (flags & EXT4_MB_DELALLOC_RESERVED)) {
758                 dquot_alloc_block_nofail(inode    656                 dquot_alloc_block_nofail(inode,
759                                 EXT4_C2B(EXT4_    657                                 EXT4_C2B(EXT4_SB(inode->i_sb), ar.len));
760         }                                         658         }
761         return ret;                               659         return ret;
762 }                                                 660 }
763                                                   661 
764 /**                                               662 /**
765  * ext4_count_free_clusters() -- count filesys    663  * ext4_count_free_clusters() -- count filesystem free clusters
766  * @sb:         superblock                        664  * @sb:         superblock
767  *                                                665  *
768  * Adds up the number of free clusters from ea    666  * Adds up the number of free clusters from each block group.
769  */                                               667  */
770 ext4_fsblk_t ext4_count_free_clusters(struct s    668 ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb)
771 {                                                 669 {
772         ext4_fsblk_t desc_count;                  670         ext4_fsblk_t desc_count;
773         struct ext4_group_desc *gdp;              671         struct ext4_group_desc *gdp;
774         ext4_group_t i;                           672         ext4_group_t i;
775         ext4_group_t ngroups = ext4_get_groups    673         ext4_group_t ngroups = ext4_get_groups_count(sb);
776         struct ext4_group_info *grp;              674         struct ext4_group_info *grp;
777 #ifdef EXT4FS_DEBUG                               675 #ifdef EXT4FS_DEBUG
778         struct ext4_super_block *es;              676         struct ext4_super_block *es;
779         ext4_fsblk_t bitmap_count;                677         ext4_fsblk_t bitmap_count;
780         unsigned int x;                           678         unsigned int x;
781         struct buffer_head *bitmap_bh = NULL;     679         struct buffer_head *bitmap_bh = NULL;
782                                                   680 
783         es = EXT4_SB(sb)->s_es;                   681         es = EXT4_SB(sb)->s_es;
784         desc_count = 0;                           682         desc_count = 0;
785         bitmap_count = 0;                         683         bitmap_count = 0;
786         gdp = NULL;                               684         gdp = NULL;
787                                                   685 
788         for (i = 0; i < ngroups; i++) {           686         for (i = 0; i < ngroups; i++) {
789                 gdp = ext4_get_group_desc(sb,     687                 gdp = ext4_get_group_desc(sb, i, NULL);
790                 if (!gdp)                         688                 if (!gdp)
791                         continue;                 689                         continue;
792                 grp = NULL;                       690                 grp = NULL;
793                 if (EXT4_SB(sb)->s_group_info)    691                 if (EXT4_SB(sb)->s_group_info)
794                         grp = ext4_get_group_i    692                         grp = ext4_get_group_info(sb, i);
795                 if (!grp || !EXT4_MB_GRP_BBITM    693                 if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
796                         desc_count += ext4_fre    694                         desc_count += ext4_free_group_clusters(sb, gdp);
797                 brelse(bitmap_bh);                695                 brelse(bitmap_bh);
798                 bitmap_bh = ext4_read_block_bi    696                 bitmap_bh = ext4_read_block_bitmap(sb, i);
799                 if (IS_ERR(bitmap_bh)) {          697                 if (IS_ERR(bitmap_bh)) {
800                         bitmap_bh = NULL;         698                         bitmap_bh = NULL;
801                         continue;                 699                         continue;
802                 }                                 700                 }
803                                                   701 
804                 x = ext4_count_free(bitmap_bh-    702                 x = ext4_count_free(bitmap_bh->b_data,
805                                     EXT4_CLUST    703                                     EXT4_CLUSTERS_PER_GROUP(sb) / 8);
806                 printk(KERN_DEBUG "group %u: s    704                 printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n",
807                         i, ext4_free_group_clu    705                         i, ext4_free_group_clusters(sb, gdp), x);
808                 bitmap_count += x;                706                 bitmap_count += x;
809         }                                         707         }
810         brelse(bitmap_bh);                        708         brelse(bitmap_bh);
811         printk(KERN_DEBUG "ext4_count_free_clu    709         printk(KERN_DEBUG "ext4_count_free_clusters: stored = %llu"
812                ", computed = %llu, %llu\n",       710                ", computed = %llu, %llu\n",
813                EXT4_NUM_B2C(EXT4_SB(sb), ext4_    711                EXT4_NUM_B2C(EXT4_SB(sb), ext4_free_blocks_count(es)),
814                desc_count, bitmap_count);         712                desc_count, bitmap_count);
815         return bitmap_count;                      713         return bitmap_count;
816 #else                                             714 #else
817         desc_count = 0;                           715         desc_count = 0;
818         for (i = 0; i < ngroups; i++) {           716         for (i = 0; i < ngroups; i++) {
819                 gdp = ext4_get_group_desc(sb,     717                 gdp = ext4_get_group_desc(sb, i, NULL);
820                 if (!gdp)                         718                 if (!gdp)
821                         continue;                 719                         continue;
822                 grp = NULL;                       720                 grp = NULL;
823                 if (EXT4_SB(sb)->s_group_info)    721                 if (EXT4_SB(sb)->s_group_info)
824                         grp = ext4_get_group_i    722                         grp = ext4_get_group_info(sb, i);
825                 if (!grp || !EXT4_MB_GRP_BBITM    723                 if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
826                         desc_count += ext4_fre    724                         desc_count += ext4_free_group_clusters(sb, gdp);
827         }                                         725         }
828                                                   726 
829         return desc_count;                        727         return desc_count;
830 #endif                                            728 #endif
831 }                                                 729 }
832                                                   730 
833 static inline int test_root(ext4_group_t a, in    731 static inline int test_root(ext4_group_t a, int b)
834 {                                                 732 {
835         while (1) {                               733         while (1) {
836                 if (a < b)                        734                 if (a < b)
837                         return 0;                 735                         return 0;
838                 if (a == b)                       736                 if (a == b)
839                         return 1;                 737                         return 1;
840                 if ((a % b) != 0)                 738                 if ((a % b) != 0)
841                         return 0;                 739                         return 0;
842                 a = a / b;                        740                 a = a / b;
843         }                                         741         }
844 }                                                 742 }
845                                                   743 
846 /**                                               744 /**
847  *      ext4_bg_has_super - number of blocks u    745  *      ext4_bg_has_super - number of blocks used by the superblock in group
848  *      @sb: superblock for filesystem            746  *      @sb: superblock for filesystem
849  *      @group: group number to check             747  *      @group: group number to check
850  *                                                748  *
851  *      Return the number of blocks used by th    749  *      Return the number of blocks used by the superblock (primary or backup)
852  *      in this group.  Currently this will be    750  *      in this group.  Currently this will be only 0 or 1.
853  */                                               751  */
854 int ext4_bg_has_super(struct super_block *sb,     752 int ext4_bg_has_super(struct super_block *sb, ext4_group_t group)
855 {                                                 753 {
856         struct ext4_super_block *es = EXT4_SB(    754         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
857                                                   755 
858         if (group == 0)                           756         if (group == 0)
859                 return 1;                         757                 return 1;
860         if (ext4_has_feature_sparse_super2(sb)    758         if (ext4_has_feature_sparse_super2(sb)) {
861                 if (group == le32_to_cpu(es->s    759                 if (group == le32_to_cpu(es->s_backup_bgs[0]) ||
862                     group == le32_to_cpu(es->s    760                     group == le32_to_cpu(es->s_backup_bgs[1]))
863                         return 1;                 761                         return 1;
864                 return 0;                         762                 return 0;
865         }                                         763         }
866         if ((group <= 1) || !ext4_has_feature_    764         if ((group <= 1) || !ext4_has_feature_sparse_super(sb))
867                 return 1;                         765                 return 1;
868         if (!(group & 1))                         766         if (!(group & 1))
869                 return 0;                         767                 return 0;
870         if (test_root(group, 3) || (test_root(    768         if (test_root(group, 3) || (test_root(group, 5)) ||
871             test_root(group, 7))                  769             test_root(group, 7))
872                 return 1;                         770                 return 1;
873                                                   771 
874         return 0;                                 772         return 0;
875 }                                                 773 }
876                                                   774 
877 static unsigned long ext4_bg_num_gdb_meta(stru    775 static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb,
878                                         ext4_g    776                                         ext4_group_t group)
879 {                                                 777 {
880         unsigned long metagroup = group / EXT4    778         unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
881         ext4_group_t first = metagroup * EXT4_    779         ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb);
882         ext4_group_t last = first + EXT4_DESC_    780         ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1;
883                                                   781 
884         if (group == first || group == first +    782         if (group == first || group == first + 1 || group == last)
885                 return 1;                         783                 return 1;
886         return 0;                                 784         return 0;
887 }                                                 785 }
888                                                   786 
889 static unsigned long ext4_bg_num_gdb_nometa(st    787 static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb,
890                                         ext4_g    788                                         ext4_group_t group)
891 {                                                 789 {
892         if (!ext4_bg_has_super(sb, group))        790         if (!ext4_bg_has_super(sb, group))
893                 return 0;                         791                 return 0;
894                                                   792 
895         if (ext4_has_feature_meta_bg(sb))         793         if (ext4_has_feature_meta_bg(sb))
896                 return le32_to_cpu(EXT4_SB(sb)    794                 return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
897         else                                      795         else
898                 return EXT4_SB(sb)->s_gdb_coun    796                 return EXT4_SB(sb)->s_gdb_count;
899 }                                                 797 }
900                                                   798 
901 /**                                               799 /**
902  *      ext4_bg_num_gdb - number of blocks use    800  *      ext4_bg_num_gdb - number of blocks used by the group table in group
903  *      @sb: superblock for filesystem            801  *      @sb: superblock for filesystem
904  *      @group: group number to check             802  *      @group: group number to check
905  *                                                803  *
906  *      Return the number of blocks used by th    804  *      Return the number of blocks used by the group descriptor table
907  *      (primary or backup) in this group.  In    805  *      (primary or backup) in this group.  In the future there may be a
908  *      different number of descriptor blocks     806  *      different number of descriptor blocks in each group.
909  */                                               807  */
910 unsigned long ext4_bg_num_gdb(struct super_blo    808 unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
911 {                                                 809 {
912         unsigned long first_meta_bg =             810         unsigned long first_meta_bg =
913                         le32_to_cpu(EXT4_SB(sb    811                         le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
914         unsigned long metagroup = group / EXT4    812         unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
915                                                   813 
916         if (!ext4_has_feature_meta_bg(sb) || m    814         if (!ext4_has_feature_meta_bg(sb) || metagroup < first_meta_bg)
917                 return ext4_bg_num_gdb_nometa(    815                 return ext4_bg_num_gdb_nometa(sb, group);
918                                                   816 
919         return ext4_bg_num_gdb_meta(sb,group);    817         return ext4_bg_num_gdb_meta(sb,group);
920                                                   818 
921 }                                                 819 }
922                                                   820 
923 /*                                                821 /*
924  * This function returns the number of file sy !! 822  * This function returns the number of file system metadata clusters at
925  * the beginning of a block group, including t    823  * the beginning of a block group, including the reserved gdt blocks.
926  */                                               824  */
927 unsigned int ext4_num_base_meta_blocks(struct  !! 825 static unsigned ext4_num_base_meta_clusters(struct super_block *sb,
928                                        ext4_gr !! 826                                      ext4_group_t block_group)
929 {                                                 827 {
930         struct ext4_sb_info *sbi = EXT4_SB(sb)    828         struct ext4_sb_info *sbi = EXT4_SB(sb);
931         unsigned num;                             829         unsigned num;
932                                                   830 
933         /* Check for superblock and gdt backup    831         /* Check for superblock and gdt backups in this group */
934         num = ext4_bg_has_super(sb, block_grou    832         num = ext4_bg_has_super(sb, block_group);
935                                                   833 
936         if (!ext4_has_feature_meta_bg(sb) ||      834         if (!ext4_has_feature_meta_bg(sb) ||
937             block_group < le32_to_cpu(sbi->s_e    835             block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) *
938                           sbi->s_desc_per_bloc    836                           sbi->s_desc_per_block) {
939                 if (num) {                        837                 if (num) {
940                         num += ext4_bg_num_gdb !! 838                         num += ext4_bg_num_gdb(sb, block_group);
941                         num += le16_to_cpu(sbi    839                         num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks);
942                 }                                 840                 }
943         } else { /* For META_BG_BLOCK_GROUPS *    841         } else { /* For META_BG_BLOCK_GROUPS */
944                 num += ext4_bg_num_gdb_meta(sb !! 842                 num += ext4_bg_num_gdb(sb, block_group);
945         }                                         843         }
946         return num;                            !! 844         return EXT4_NUM_B2C(sbi, num);
947 }                                                 845 }
948                                                << 
949 static unsigned int ext4_num_base_meta_cluster << 
950                                                << 
951 {                                              << 
952         return EXT4_NUM_B2C(EXT4_SB(sb), ext4_ << 
953 }                                              << 
954                                                << 
955 /**                                               846 /**
956  *      ext4_inode_to_goal_block - return a hi    847  *      ext4_inode_to_goal_block - return a hint for block allocation
957  *      @inode: inode for block allocation        848  *      @inode: inode for block allocation
958  *                                                849  *
959  *      Return the ideal location to start all    850  *      Return the ideal location to start allocating blocks for a
960  *      newly created inode.                      851  *      newly created inode.
961  */                                               852  */
962 ext4_fsblk_t ext4_inode_to_goal_block(struct i    853 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode)
963 {                                                 854 {
964         struct ext4_inode_info *ei = EXT4_I(in    855         struct ext4_inode_info *ei = EXT4_I(inode);
965         ext4_group_t block_group;                 856         ext4_group_t block_group;
966         ext4_grpblk_t colour;                     857         ext4_grpblk_t colour;
967         int flex_size = ext4_flex_bg_size(EXT4    858         int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
968         ext4_fsblk_t bg_start;                    859         ext4_fsblk_t bg_start;
969         ext4_fsblk_t last_block;                  860         ext4_fsblk_t last_block;
970                                                   861 
971         block_group = ei->i_block_group;          862         block_group = ei->i_block_group;
972         if (flex_size >= EXT4_FLEX_SIZE_DIR_AL    863         if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
973                 /*                                864                 /*
974                  * If there are at least EXT4_    865                  * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
975                  * block groups per flexgroup,    866                  * block groups per flexgroup, reserve the first block
976                  * group for directories and s    867                  * group for directories and special files.  Regular
977                  * files will start at the sec    868                  * files will start at the second block group.  This
978                  * tends to speed up directory    869                  * tends to speed up directory access and improves
979                  * fsck times.                    870                  * fsck times.
980                  */                               871                  */
981                 block_group &= ~(flex_size-1);    872                 block_group &= ~(flex_size-1);
982                 if (S_ISREG(inode->i_mode))       873                 if (S_ISREG(inode->i_mode))
983                         block_group++;            874                         block_group++;
984         }                                         875         }
985         bg_start = ext4_group_first_block_no(i    876         bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
986         last_block = ext4_blocks_count(EXT4_SB    877         last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
987                                                   878 
988         /*                                        879         /*
989          * If we are doing delayed allocation,    880          * If we are doing delayed allocation, we don't need take
990          * colour into account.                   881          * colour into account.
991          */                                       882          */
992         if (test_opt(inode->i_sb, DELALLOC))      883         if (test_opt(inode->i_sb, DELALLOC))
993                 return bg_start;                  884                 return bg_start;
994                                                   885 
995         if (bg_start + EXT4_BLOCKS_PER_GROUP(i    886         if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
996                 colour = (task_pid_nr(current) !! 887                 colour = (current->pid % 16) *
997                         (EXT4_BLOCKS_PER_GROUP    888                         (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
998         else                                      889         else
999                 colour = (task_pid_nr(current) !! 890                 colour = (current->pid % 16) * ((last_block - bg_start) / 16);
1000                         ((last_block - bg_sta << 
1001         return bg_start + colour;                891         return bg_start + colour;
1002 }                                                892 }
1003                                                  893 
1004                                                  894 

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