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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-5.19.17)


  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                                                   100 
106         /*                                        101         /*
107          * Account and record inode table clus !! 102          * For the allocation bitmaps and inode table, we first need
108          * is in the block group, or inode tab !! 103          * to check to see if the block is in the block group.  If it
109          * [-1, -1] and won't overlap with blo !! 104          * is, then check to see if the cluster is already accounted
110          * accounted below.                    !! 105          * for in the clusters used for the base metadata cluster, or
111          */                                    !! 106          * if we can increment the base metadata cluster to include
112         itbl_blk_start = ext4_inode_table(sb,  !! 107          * that block.  Otherwise, we will have to track the cluster
113         itbl_blk_end = itbl_blk_start + sbi->s !! 108          * used for the allocation bitmap or inode table explicitly.
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                                                << 
127         /*                                     << 
128          * For the allocation bitmaps, we firs << 
129          * if the block is in the block group. << 
130          * to see if the cluster is already ac << 
131          * used for the base metadata cluster  << 
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                  */                            << 
152                 if (inode_cluster != block_clu << 
153                     inode_cluster >= base_clus << 
154                     (inode_cluster < itbl_clus << 
155                     inode_cluster > itbl_clust << 
156                         num_clusters++;           130                         num_clusters++;
                                                   >> 131                         inode_cluster = -1;
                                                   >> 132                 }
157         }                                         133         }
158                                                   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                         }
                                                   >> 146                         num_clusters++;
                                                   >> 147                         itbl_cluster = c;
                                                   >> 148                 }
                                                   >> 149         }
                                                   >> 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;
190                                                   187 
191         ASSERT(buffer_locked(bh));                188         ASSERT(buffer_locked(bh));
192                                                   189 
                                                   >> 190         /* If checksum is bad mark all blocks used to prevent allocation
                                                   >> 191          * essentially implementing a per-group read-only flag. */
193         if (!ext4_group_desc_csum_verify(sb, b    192         if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
194                 ext4_mark_group_bitmap_corrupt    193                 ext4_mark_group_bitmap_corrupted(sb, block_group,
195                                         EXT4_G    194                                         EXT4_GROUP_INFO_BBITMAP_CORRUPT |
196                                         EXT4_G    195                                         EXT4_GROUP_INFO_IBITMAP_CORRUPT);
197                 return -EFSBADCRC;                196                 return -EFSBADCRC;
198         }                                         197         }
199         memset(bh->b_data, 0, sb->s_blocksize)    198         memset(bh->b_data, 0, sb->s_blocksize);
200                                                   199 
201         bit_max = ext4_num_base_meta_clusters(    200         bit_max = ext4_num_base_meta_clusters(sb, block_group);
202         if ((bit_max >> 3) >= bh->b_size)         201         if ((bit_max >> 3) >= bh->b_size)
203                 return -EFSCORRUPTED;             202                 return -EFSCORRUPTED;
204                                                   203 
205         for (bit = 0; bit < bit_max; bit++)       204         for (bit = 0; bit < bit_max; bit++)
206                 ext4_set_bit(bit, bh->b_data);    205                 ext4_set_bit(bit, bh->b_data);
207                                                   206 
208         start = ext4_group_first_block_no(sb,     207         start = ext4_group_first_block_no(sb, block_group);
209                                                   208 
210         /* Set bits for block and inode bitmap    209         /* Set bits for block and inode bitmaps, and inode table */
211         tmp = ext4_block_bitmap(sb, gdp);         210         tmp = ext4_block_bitmap(sb, gdp);
212         if (ext4_block_in_group(sb, tmp, block    211         if (ext4_block_in_group(sb, tmp, block_group))
213                 ext4_set_bit(EXT4_B2C(sbi, tmp    212                 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
214                                                   213 
215         tmp = ext4_inode_bitmap(sb, gdp);         214         tmp = ext4_inode_bitmap(sb, gdp);
216         if (ext4_block_in_group(sb, tmp, block    215         if (ext4_block_in_group(sb, tmp, block_group))
217                 ext4_set_bit(EXT4_B2C(sbi, tmp    216                 ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
218                                                   217 
219         tmp = ext4_inode_table(sb, gdp);          218         tmp = ext4_inode_table(sb, gdp);
220         for (; tmp < ext4_inode_table(sb, gdp)    219         for (; tmp < ext4_inode_table(sb, gdp) +
221                      sbi->s_itb_per_group; tmp    220                      sbi->s_itb_per_group; tmp++) {
222                 if (ext4_block_in_group(sb, tm    221                 if (ext4_block_in_group(sb, tmp, block_group))
223                         ext4_set_bit(EXT4_B2C(    222                         ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
224         }                                         223         }
225                                                   224 
226         /*                                        225         /*
227          * Also if the number of blocks within    226          * Also if the number of blocks within the group is less than
228          * the blocksize * 8 ( which is the si    227          * the blocksize * 8 ( which is the size of bitmap ), set rest
229          * of the block bitmap to 1               228          * of the block bitmap to 1
230          */                                       229          */
231         ext4_mark_bitmap_end(num_clusters_in_g    230         ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group),
232                              sb->s_blocksize *    231                              sb->s_blocksize * 8, bh->b_data);
233         return 0;                                 232         return 0;
234 }                                                 233 }
235                                                   234 
236 /* Return the number of free blocks in a block    235 /* Return the number of free blocks in a block group.  It is used when
237  * the block bitmap is uninitialized, so we ca    236  * the block bitmap is uninitialized, so we can't just count the bits
238  * in the bitmap. */                              237  * in the bitmap. */
239 unsigned ext4_free_clusters_after_init(struct     238 unsigned ext4_free_clusters_after_init(struct super_block *sb,
240                                        ext4_gr    239                                        ext4_group_t block_group,
241                                        struct     240                                        struct ext4_group_desc *gdp)
242 {                                                 241 {
243         return num_clusters_in_group(sb, block    242         return num_clusters_in_group(sb, block_group) -
244                 ext4_num_overhead_clusters(sb,    243                 ext4_num_overhead_clusters(sb, block_group, gdp);
245 }                                                 244 }
246                                                   245 
247 /*                                                246 /*
248  * The free blocks are managed by bitmaps.  A     247  * The free blocks are managed by bitmaps.  A file system contains several
249  * blocks groups.  Each group contains 1 bitma    248  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
250  * block for inodes, N blocks for the inode ta    249  * block for inodes, N blocks for the inode table and data blocks.
251  *                                                250  *
252  * The file system contains group descriptors     251  * The file system contains group descriptors which are located after the
253  * super block.  Each descriptor contains the     252  * super block.  Each descriptor contains the number of the bitmap block and
254  * the free blocks count in the block.  The de    253  * the free blocks count in the block.  The descriptors are loaded in memory
255  * when a file system is mounted (see ext4_fil    254  * when a file system is mounted (see ext4_fill_super).
256  */                                               255  */
257                                                   256 
258 /**                                               257 /**
259  * ext4_get_group_desc() -- load group descrip    258  * ext4_get_group_desc() -- load group descriptor from disk
260  * @sb:                 super block               259  * @sb:                 super block
261  * @block_group:        given block group         260  * @block_group:        given block group
262  * @bh:                 pointer to the buffer     261  * @bh:                 pointer to the buffer head to store the block
263  *                      group descriptor          262  *                      group descriptor
264  */                                               263  */
265 struct ext4_group_desc * ext4_get_group_desc(s    264 struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb,
266                                              e    265                                              ext4_group_t block_group,
267                                              s    266                                              struct buffer_head **bh)
268 {                                                 267 {
269         unsigned int group_desc;                  268         unsigned int group_desc;
270         unsigned int offset;                      269         unsigned int offset;
271         ext4_group_t ngroups = ext4_get_groups    270         ext4_group_t ngroups = ext4_get_groups_count(sb);
272         struct ext4_group_desc *desc;             271         struct ext4_group_desc *desc;
273         struct ext4_sb_info *sbi = EXT4_SB(sb)    272         struct ext4_sb_info *sbi = EXT4_SB(sb);
274         struct buffer_head *bh_p;                 273         struct buffer_head *bh_p;
275                                                   274 
276         KUNIT_STATIC_STUB_REDIRECT(ext4_get_gr << 
277                                    sb, block_g << 
278                                                << 
279         if (block_group >= ngroups) {             275         if (block_group >= ngroups) {
280                 ext4_error(sb, "block_group >=    276                 ext4_error(sb, "block_group >= groups_count - block_group = %u,"
281                            " groups_count = %u    277                            " groups_count = %u", block_group, ngroups);
282                                                   278 
283                 return NULL;                      279                 return NULL;
284         }                                         280         }
285                                                   281 
286         group_desc = block_group >> EXT4_DESC_    282         group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
287         offset = block_group & (EXT4_DESC_PER_    283         offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
288         bh_p = sbi_array_rcu_deref(sbi, s_grou    284         bh_p = sbi_array_rcu_deref(sbi, s_group_desc, group_desc);
289         /*                                        285         /*
290          * sbi_array_rcu_deref returns with rc    286          * sbi_array_rcu_deref returns with rcu unlocked, this is ok since
291          * the pointer being dereferenced won'    287          * the pointer being dereferenced won't be dereferenced again. By
292          * looking at the usage in add_new_gdb    288          * looking at the usage in add_new_gdb() the value isn't modified,
293          * just the pointer, and so it remains    289          * just the pointer, and so it remains valid.
294          */                                       290          */
295         if (!bh_p) {                              291         if (!bh_p) {
296                 ext4_error(sb, "Group descript    292                 ext4_error(sb, "Group descriptor not loaded - "
297                            "block_group = %u,     293                            "block_group = %u, group_desc = %u, desc = %u",
298                            block_group, group_    294                            block_group, group_desc, offset);
299                 return NULL;                      295                 return NULL;
300         }                                         296         }
301                                                   297 
302         desc = (struct ext4_group_desc *)(        298         desc = (struct ext4_group_desc *)(
303                 (__u8 *)bh_p->b_data +            299                 (__u8 *)bh_p->b_data +
304                 offset * EXT4_DESC_SIZE(sb));     300                 offset * EXT4_DESC_SIZE(sb));
305         if (bh)                                   301         if (bh)
306                 *bh = bh_p;                       302                 *bh = bh_p;
307         return desc;                              303         return desc;
308 }                                                 304 }
309                                                   305 
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 /*                                                306 /*
341  * Return the block number which was discovere    307  * Return the block number which was discovered to be invalid, or 0 if
342  * the block bitmap is valid.                     308  * the block bitmap is valid.
343  */                                               309  */
344 static ext4_fsblk_t ext4_valid_block_bitmap(st    310 static ext4_fsblk_t ext4_valid_block_bitmap(struct super_block *sb,
345                                             st    311                                             struct ext4_group_desc *desc,
346                                             ex    312                                             ext4_group_t block_group,
347                                             st    313                                             struct buffer_head *bh)
348 {                                                 314 {
349         struct ext4_sb_info *sbi = EXT4_SB(sb)    315         struct ext4_sb_info *sbi = EXT4_SB(sb);
350         ext4_grpblk_t offset;                     316         ext4_grpblk_t offset;
351         ext4_grpblk_t next_zero_bit;              317         ext4_grpblk_t next_zero_bit;
352         ext4_grpblk_t max_bit = EXT4_CLUSTERS_    318         ext4_grpblk_t max_bit = EXT4_CLUSTERS_PER_GROUP(sb);
353         ext4_fsblk_t blk;                         319         ext4_fsblk_t blk;
354         ext4_fsblk_t group_first_block;           320         ext4_fsblk_t group_first_block;
355                                                   321 
356         if (ext4_has_feature_flex_bg(sb)) {       322         if (ext4_has_feature_flex_bg(sb)) {
357                 /* with FLEX_BG, the inode/blo    323                 /* with FLEX_BG, the inode/block bitmaps and itable
358                  * blocks may not be in the gr    324                  * blocks may not be in the group at all
359                  * so the bitmap validation wi    325                  * so the bitmap validation will be skipped for those groups
360                  * or it has to also read the     326                  * or it has to also read the block group where the bitmaps
361                  * are located to verify they     327                  * are located to verify they are set.
362                  */                               328                  */
363                 return 0;                         329                 return 0;
364         }                                         330         }
365         group_first_block = ext4_group_first_b    331         group_first_block = ext4_group_first_block_no(sb, block_group);
366                                                   332 
367         /* check whether block bitmap block nu    333         /* check whether block bitmap block number is set */
368         blk = ext4_block_bitmap(sb, desc);        334         blk = ext4_block_bitmap(sb, desc);
369         offset = blk - group_first_block;         335         offset = blk - group_first_block;
370         if (offset < 0 || EXT4_B2C(sbi, offset    336         if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||
371             !ext4_test_bit(EXT4_B2C(sbi, offse    337             !ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
372                 /* bad block bitmap */            338                 /* bad block bitmap */
373                 return blk;                       339                 return blk;
374                                                   340 
375         /* check whether the inode bitmap bloc    341         /* check whether the inode bitmap block number is set */
376         blk = ext4_inode_bitmap(sb, desc);        342         blk = ext4_inode_bitmap(sb, desc);
377         offset = blk - group_first_block;         343         offset = blk - group_first_block;
378         if (offset < 0 || EXT4_B2C(sbi, offset    344         if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||
379             !ext4_test_bit(EXT4_B2C(sbi, offse    345             !ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data))
380                 /* bad block bitmap */            346                 /* bad block bitmap */
381                 return blk;                       347                 return blk;
382                                                   348 
383         /* check whether the inode table block    349         /* check whether the inode table block number is set */
384         blk = ext4_inode_table(sb, desc);         350         blk = ext4_inode_table(sb, desc);
385         offset = blk - group_first_block;         351         offset = blk - group_first_block;
386         if (offset < 0 || EXT4_B2C(sbi, offset    352         if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||
387             EXT4_B2C(sbi, offset + sbi->s_itb_ !! 353             EXT4_B2C(sbi, offset + sbi->s_itb_per_group) >= max_bit)
388                 return blk;                       354                 return blk;
389         next_zero_bit = ext4_find_next_zero_bi    355         next_zero_bit = ext4_find_next_zero_bit(bh->b_data,
390                         EXT4_B2C(sbi, offset + !! 356                         EXT4_B2C(sbi, offset + sbi->s_itb_per_group),
391                         EXT4_B2C(sbi, offset))    357                         EXT4_B2C(sbi, offset));
392         if (next_zero_bit <                       358         if (next_zero_bit <
393             EXT4_B2C(sbi, offset + sbi->s_itb_ !! 359             EXT4_B2C(sbi, offset + sbi->s_itb_per_group))
394                 /* bad bitmap for inode tables    360                 /* bad bitmap for inode tables */
395                 return blk;                       361                 return blk;
396         return 0;                                 362         return 0;
397 }                                                 363 }
398                                                   364 
399 static int ext4_validate_block_bitmap(struct s    365 static int ext4_validate_block_bitmap(struct super_block *sb,
400                                       struct e    366                                       struct ext4_group_desc *desc,
401                                       ext4_gro    367                                       ext4_group_t block_group,
402                                       struct b    368                                       struct buffer_head *bh)
403 {                                                 369 {
404         ext4_fsblk_t    blk;                      370         ext4_fsblk_t    blk;
405         struct ext4_group_info *grp;              371         struct ext4_group_info *grp;
406                                                   372 
407         if (EXT4_SB(sb)->s_mount_state & EXT4_    373         if (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY)
408                 return 0;                         374                 return 0;
409                                                   375 
410         grp = ext4_get_group_info(sb, block_gr    376         grp = ext4_get_group_info(sb, block_group);
411                                                   377 
412         if (buffer_verified(bh))                  378         if (buffer_verified(bh))
413                 return 0;                         379                 return 0;
414         if (!grp || EXT4_MB_GRP_BBITMAP_CORRUP !! 380         if (EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
415                 return -EFSCORRUPTED;             381                 return -EFSCORRUPTED;
416                                                   382 
417         ext4_lock_group(sb, block_group);         383         ext4_lock_group(sb, block_group);
418         if (buffer_verified(bh))                  384         if (buffer_verified(bh))
419                 goto verified;                    385                 goto verified;
420         if (unlikely(!ext4_block_bitmap_csum_v !! 386         if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group,
                                                   >> 387                                                     desc, bh) ||
421                      ext4_simulate_fail(sb, EX    388                      ext4_simulate_fail(sb, EXT4_SIM_BBITMAP_CRC))) {
422                 ext4_unlock_group(sb, block_gr    389                 ext4_unlock_group(sb, block_group);
423                 ext4_error(sb, "bg %u: bad blo    390                 ext4_error(sb, "bg %u: bad block bitmap checksum", block_group);
424                 ext4_mark_group_bitmap_corrupt    391                 ext4_mark_group_bitmap_corrupted(sb, block_group,
425                                         EXT4_G    392                                         EXT4_GROUP_INFO_BBITMAP_CORRUPT);
426                 return -EFSBADCRC;                393                 return -EFSBADCRC;
427         }                                         394         }
428         blk = ext4_valid_block_bitmap(sb, desc    395         blk = ext4_valid_block_bitmap(sb, desc, block_group, bh);
429         if (unlikely(blk != 0)) {                 396         if (unlikely(blk != 0)) {
430                 ext4_unlock_group(sb, block_gr    397                 ext4_unlock_group(sb, block_group);
431                 ext4_error(sb, "bg %u: block %    398                 ext4_error(sb, "bg %u: block %llu: invalid block bitmap",
432                            block_group, blk);     399                            block_group, blk);
433                 ext4_mark_group_bitmap_corrupt    400                 ext4_mark_group_bitmap_corrupted(sb, block_group,
434                                         EXT4_G    401                                         EXT4_GROUP_INFO_BBITMAP_CORRUPT);
435                 return -EFSCORRUPTED;             402                 return -EFSCORRUPTED;
436         }                                         403         }
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;          << 
445         }                                      << 
446         set_buffer_verified(bh);                  404         set_buffer_verified(bh);
447 verified:                                         405 verified:
448         ext4_unlock_group(sb, block_group);       406         ext4_unlock_group(sb, block_group);
449         return 0;                                 407         return 0;
450 }                                                 408 }
451                                                   409 
452 /**                                               410 /**
453  * ext4_read_block_bitmap_nowait()                411  * ext4_read_block_bitmap_nowait()
454  * @sb:                 super block               412  * @sb:                 super block
455  * @block_group:        given block group         413  * @block_group:        given block group
456  * @ignore_locked:      ignore locked buffers     414  * @ignore_locked:      ignore locked buffers
457  *                                                415  *
458  * Read the bitmap for a given block_group,and    416  * Read the bitmap for a given block_group,and validate the
459  * bits for block/inode/inode tables are set i    417  * bits for block/inode/inode tables are set in the bitmaps
460  *                                                418  *
461  * Return buffer_head on success or an ERR_PTR    419  * Return buffer_head on success or an ERR_PTR in case of failure.
462  */                                               420  */
463 struct buffer_head *                              421 struct buffer_head *
464 ext4_read_block_bitmap_nowait(struct super_blo    422 ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group,
465                               bool ignore_lock    423                               bool ignore_locked)
466 {                                                 424 {
467         struct ext4_group_desc *desc;             425         struct ext4_group_desc *desc;
468         struct ext4_sb_info *sbi = EXT4_SB(sb)    426         struct ext4_sb_info *sbi = EXT4_SB(sb);
469         struct buffer_head *bh;                   427         struct buffer_head *bh;
470         ext4_fsblk_t bitmap_blk;                  428         ext4_fsblk_t bitmap_blk;
471         int err;                                  429         int err;
472                                                   430 
473         KUNIT_STATIC_STUB_REDIRECT(ext4_read_b << 
474                                    sb, block_g << 
475                                                << 
476         desc = ext4_get_group_desc(sb, block_g    431         desc = ext4_get_group_desc(sb, block_group, NULL);
477         if (!desc)                                432         if (!desc)
478                 return ERR_PTR(-EFSCORRUPTED);    433                 return ERR_PTR(-EFSCORRUPTED);
479         bitmap_blk = ext4_block_bitmap(sb, des    434         bitmap_blk = ext4_block_bitmap(sb, desc);
480         if ((bitmap_blk <= le32_to_cpu(sbi->s_    435         if ((bitmap_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
481             (bitmap_blk >= ext4_blocks_count(s    436             (bitmap_blk >= ext4_blocks_count(sbi->s_es))) {
482                 ext4_error(sb, "Invalid block     437                 ext4_error(sb, "Invalid block bitmap block %llu in "
483                            "block_group %u", b    438                            "block_group %u", bitmap_blk, block_group);
484                 ext4_mark_group_bitmap_corrupt    439                 ext4_mark_group_bitmap_corrupted(sb, block_group,
485                                         EXT4_G    440                                         EXT4_GROUP_INFO_BBITMAP_CORRUPT);
486                 return ERR_PTR(-EFSCORRUPTED);    441                 return ERR_PTR(-EFSCORRUPTED);
487         }                                         442         }
488         bh = sb_getblk(sb, bitmap_blk);           443         bh = sb_getblk(sb, bitmap_blk);
489         if (unlikely(!bh)) {                      444         if (unlikely(!bh)) {
490                 ext4_warning(sb, "Cannot get b    445                 ext4_warning(sb, "Cannot get buffer for block bitmap - "
491                              "block_group = %u    446                              "block_group = %u, block_bitmap = %llu",
492                              block_group, bitm    447                              block_group, bitmap_blk);
493                 return ERR_PTR(-ENOMEM);          448                 return ERR_PTR(-ENOMEM);
494         }                                         449         }
495                                                   450 
496         if (ignore_locked && buffer_locked(bh)    451         if (ignore_locked && buffer_locked(bh)) {
497                 /* buffer under IO already, re    452                 /* buffer under IO already, return if called for prefetching */
498                 put_bh(bh);                       453                 put_bh(bh);
499                 return NULL;                      454                 return NULL;
500         }                                         455         }
501                                                   456 
502         if (bitmap_uptodate(bh))                  457         if (bitmap_uptodate(bh))
503                 goto verify;                      458                 goto verify;
504                                                   459 
505         lock_buffer(bh);                          460         lock_buffer(bh);
506         if (bitmap_uptodate(bh)) {                461         if (bitmap_uptodate(bh)) {
507                 unlock_buffer(bh);                462                 unlock_buffer(bh);
508                 goto verify;                      463                 goto verify;
509         }                                         464         }
510         ext4_lock_group(sb, block_group);         465         ext4_lock_group(sb, block_group);
511         if (ext4_has_group_desc_csum(sb) &&       466         if (ext4_has_group_desc_csum(sb) &&
512             (desc->bg_flags & cpu_to_le16(EXT4    467             (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
513                 if (block_group == 0) {           468                 if (block_group == 0) {
514                         ext4_unlock_group(sb,     469                         ext4_unlock_group(sb, block_group);
515                         unlock_buffer(bh);        470                         unlock_buffer(bh);
516                         ext4_error(sb, "Block     471                         ext4_error(sb, "Block bitmap for bg 0 marked "
517                                    "uninitiali    472                                    "uninitialized");
518                         err = -EFSCORRUPTED;      473                         err = -EFSCORRUPTED;
519                         goto out;                 474                         goto out;
520                 }                                 475                 }
521                 err = ext4_init_block_bitmap(s    476                 err = ext4_init_block_bitmap(sb, bh, block_group, desc);
522                 if (err) {                     << 
523                         ext4_unlock_group(sb,  << 
524                         unlock_buffer(bh);     << 
525                         ext4_error(sb, "Failed << 
526                                    "%u: %d", b << 
527                         goto out;              << 
528                 }                              << 
529                 set_bitmap_uptodate(bh);          477                 set_bitmap_uptodate(bh);
530                 set_buffer_uptodate(bh);          478                 set_buffer_uptodate(bh);
531                 set_buffer_verified(bh);          479                 set_buffer_verified(bh);
532                 ext4_unlock_group(sb, block_gr    480                 ext4_unlock_group(sb, block_group);
533                 unlock_buffer(bh);                481                 unlock_buffer(bh);
534                 return bh;                     !! 482                 if (err) {
                                                   >> 483                         ext4_error(sb, "Failed to init block bitmap for group "
                                                   >> 484                                    "%u: %d", block_group, err);
                                                   >> 485                         goto out;
                                                   >> 486                 }
                                                   >> 487                 goto verify;
535         }                                         488         }
536         ext4_unlock_group(sb, block_group);       489         ext4_unlock_group(sb, block_group);
537         if (buffer_uptodate(bh)) {                490         if (buffer_uptodate(bh)) {
538                 /*                                491                 /*
539                  * if not uninit if bh is upto    492                  * if not uninit if bh is uptodate,
540                  * bitmap is also uptodate        493                  * bitmap is also uptodate
541                  */                               494                  */
542                 set_bitmap_uptodate(bh);          495                 set_bitmap_uptodate(bh);
543                 unlock_buffer(bh);                496                 unlock_buffer(bh);
544                 goto verify;                      497                 goto verify;
545         }                                         498         }
546         /*                                        499         /*
547          * submit the buffer_head for reading     500          * submit the buffer_head for reading
548          */                                       501          */
549         set_buffer_new(bh);                       502         set_buffer_new(bh);
550         trace_ext4_read_block_bitmap_load(sb,     503         trace_ext4_read_block_bitmap_load(sb, block_group, ignore_locked);
551         ext4_read_bh_nowait(bh, REQ_META | REQ    504         ext4_read_bh_nowait(bh, REQ_META | REQ_PRIO |
552                             (ignore_locked ? R    505                             (ignore_locked ? REQ_RAHEAD : 0),
553                             ext4_end_bitmap_re    506                             ext4_end_bitmap_read);
554         return bh;                                507         return bh;
555 verify:                                           508 verify:
556         err = ext4_validate_block_bitmap(sb, d    509         err = ext4_validate_block_bitmap(sb, desc, block_group, bh);
557         if (err)                                  510         if (err)
558                 goto out;                         511                 goto out;
559         return bh;                                512         return bh;
560 out:                                              513 out:
561         put_bh(bh);                               514         put_bh(bh);
562         return ERR_PTR(err);                      515         return ERR_PTR(err);
563 }                                                 516 }
564                                                   517 
565 /* Returns 0 on success, -errno on error */       518 /* Returns 0 on success, -errno on error */
566 int ext4_wait_block_bitmap(struct super_block     519 int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group,
567                            struct buffer_head     520                            struct buffer_head *bh)
568 {                                                 521 {
569         struct ext4_group_desc *desc;             522         struct ext4_group_desc *desc;
570                                                   523 
571         KUNIT_STATIC_STUB_REDIRECT(ext4_wait_b << 
572                                    sb, block_g << 
573                                                << 
574         if (!buffer_new(bh))                      524         if (!buffer_new(bh))
575                 return 0;                         525                 return 0;
576         desc = ext4_get_group_desc(sb, block_g    526         desc = ext4_get_group_desc(sb, block_group, NULL);
577         if (!desc)                                527         if (!desc)
578                 return -EFSCORRUPTED;             528                 return -EFSCORRUPTED;
579         wait_on_buffer(bh);                       529         wait_on_buffer(bh);
580         ext4_simulate_fail_bh(sb, bh, EXT4_SIM    530         ext4_simulate_fail_bh(sb, bh, EXT4_SIM_BBITMAP_EIO);
581         if (!buffer_uptodate(bh)) {               531         if (!buffer_uptodate(bh)) {
582                 ext4_error_err(sb, EIO, "Canno    532                 ext4_error_err(sb, EIO, "Cannot read block bitmap - "
583                                "block_group =     533                                "block_group = %u, block_bitmap = %llu",
584                                block_group, (u    534                                block_group, (unsigned long long) bh->b_blocknr);
585                 ext4_mark_group_bitmap_corrupt    535                 ext4_mark_group_bitmap_corrupted(sb, block_group,
586                                         EXT4_G    536                                         EXT4_GROUP_INFO_BBITMAP_CORRUPT);
587                 return -EIO;                      537                 return -EIO;
588         }                                         538         }
589         clear_buffer_new(bh);                     539         clear_buffer_new(bh);
590         /* Panic or remount fs read-only if bl    540         /* Panic or remount fs read-only if block bitmap is invalid */
591         return ext4_validate_block_bitmap(sb,     541         return ext4_validate_block_bitmap(sb, desc, block_group, bh);
592 }                                                 542 }
593                                                   543 
594 struct buffer_head *                              544 struct buffer_head *
595 ext4_read_block_bitmap(struct super_block *sb,    545 ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
596 {                                                 546 {
597         struct buffer_head *bh;                   547         struct buffer_head *bh;
598         int err;                                  548         int err;
599                                                   549 
600         bh = ext4_read_block_bitmap_nowait(sb,    550         bh = ext4_read_block_bitmap_nowait(sb, block_group, false);
601         if (IS_ERR(bh))                           551         if (IS_ERR(bh))
602                 return bh;                        552                 return bh;
603         err = ext4_wait_block_bitmap(sb, block    553         err = ext4_wait_block_bitmap(sb, block_group, bh);
604         if (err) {                                554         if (err) {
605                 put_bh(bh);                       555                 put_bh(bh);
606                 return ERR_PTR(err);              556                 return ERR_PTR(err);
607         }                                         557         }
608         return bh;                                558         return bh;
609 }                                                 559 }
610                                                   560 
611 /**                                               561 /**
612  * ext4_has_free_clusters()                       562  * ext4_has_free_clusters()
613  * @sbi:        in-core super block structure.    563  * @sbi:        in-core super block structure.
614  * @nclusters:  number of needed blocks           564  * @nclusters:  number of needed blocks
615  * @flags:      flags from ext4_mb_new_blocks(    565  * @flags:      flags from ext4_mb_new_blocks()
616  *                                                566  *
617  * Check if filesystem has nclusters free & av    567  * Check if filesystem has nclusters free & available for allocation.
618  * On success return 1, return 0 on failure.      568  * On success return 1, return 0 on failure.
619  */                                               569  */
620 static int ext4_has_free_clusters(struct ext4_    570 static int ext4_has_free_clusters(struct ext4_sb_info *sbi,
621                                   s64 ncluster    571                                   s64 nclusters, unsigned int flags)
622 {                                                 572 {
623         s64 free_clusters, dirty_clusters, rsv    573         s64 free_clusters, dirty_clusters, rsv, resv_clusters;
624         struct percpu_counter *fcc = &sbi->s_f    574         struct percpu_counter *fcc = &sbi->s_freeclusters_counter;
625         struct percpu_counter *dcc = &sbi->s_d    575         struct percpu_counter *dcc = &sbi->s_dirtyclusters_counter;
626                                                   576 
627         free_clusters  = percpu_counter_read_p    577         free_clusters  = percpu_counter_read_positive(fcc);
628         dirty_clusters = percpu_counter_read_p    578         dirty_clusters = percpu_counter_read_positive(dcc);
629         resv_clusters = atomic64_read(&sbi->s_    579         resv_clusters = atomic64_read(&sbi->s_resv_clusters);
630                                                   580 
631         /*                                        581         /*
632          * r_blocks_count should always be mul    582          * r_blocks_count should always be multiple of the cluster ratio so
633          * we are safe to do a plane bit shift    583          * we are safe to do a plane bit shift only.
634          */                                       584          */
635         rsv = (ext4_r_blocks_count(sbi->s_es)     585         rsv = (ext4_r_blocks_count(sbi->s_es) >> sbi->s_cluster_bits) +
636               resv_clusters;                      586               resv_clusters;
637                                                   587 
638         if (free_clusters - (nclusters + rsv +    588         if (free_clusters - (nclusters + rsv + dirty_clusters) <
639                                         EXT4_F    589                                         EXT4_FREECLUSTERS_WATERMARK) {
640                 free_clusters  = percpu_counte    590                 free_clusters  = percpu_counter_sum_positive(fcc);
641                 dirty_clusters = percpu_counte    591                 dirty_clusters = percpu_counter_sum_positive(dcc);
642         }                                         592         }
643         /* Check whether we have space after a    593         /* Check whether we have space after accounting for current
644          * dirty clusters & root reserved clus    594          * dirty clusters & root reserved clusters.
645          */                                       595          */
646         if (free_clusters >= (rsv + nclusters     596         if (free_clusters >= (rsv + nclusters + dirty_clusters))
647                 return 1;                         597                 return 1;
648                                                   598 
649         /* Hm, nope.  Are (enough) root reserv    599         /* Hm, nope.  Are (enough) root reserved clusters available? */
650         if (uid_eq(sbi->s_resuid, current_fsui    600         if (uid_eq(sbi->s_resuid, current_fsuid()) ||
651             (!gid_eq(sbi->s_resgid, GLOBAL_ROO    601             (!gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) && in_group_p(sbi->s_resgid)) ||
652             capable(CAP_SYS_RESOURCE) ||          602             capable(CAP_SYS_RESOURCE) ||
653             (flags & EXT4_MB_USE_ROOT_BLOCKS))    603             (flags & EXT4_MB_USE_ROOT_BLOCKS)) {
654                                                   604 
655                 if (free_clusters >= (ncluster    605                 if (free_clusters >= (nclusters + dirty_clusters +
656                                       resv_clu    606                                       resv_clusters))
657                         return 1;                 607                         return 1;
658         }                                         608         }
659         /* No free blocks. Let's see if we can    609         /* No free blocks. Let's see if we can dip into reserved pool */
660         if (flags & EXT4_MB_USE_RESERVED) {       610         if (flags & EXT4_MB_USE_RESERVED) {
661                 if (free_clusters >= (ncluster    611                 if (free_clusters >= (nclusters + dirty_clusters))
662                         return 1;                 612                         return 1;
663         }                                         613         }
664                                                   614 
665         return 0;                                 615         return 0;
666 }                                                 616 }
667                                                   617 
668 int ext4_claim_free_clusters(struct ext4_sb_in    618 int ext4_claim_free_clusters(struct ext4_sb_info *sbi,
669                              s64 nclusters, un    619                              s64 nclusters, unsigned int flags)
670 {                                                 620 {
671         if (ext4_has_free_clusters(sbi, nclust    621         if (ext4_has_free_clusters(sbi, nclusters, flags)) {
672                 percpu_counter_add(&sbi->s_dir    622                 percpu_counter_add(&sbi->s_dirtyclusters_counter, nclusters);
673                 return 0;                         623                 return 0;
674         } else                                    624         } else
675                 return -ENOSPC;                   625                 return -ENOSPC;
676 }                                                 626 }
677                                                   627 
678 /**                                               628 /**
679  * ext4_should_retry_alloc() - check if a bloc    629  * ext4_should_retry_alloc() - check if a block allocation should be retried
680  * @sb:                 superblock                630  * @sb:                 superblock
681  * @retries:            number of retry attemp    631  * @retries:            number of retry attempts made so far
682  *                                                632  *
683  * ext4_should_retry_alloc() is called when EN    633  * ext4_should_retry_alloc() is called when ENOSPC is returned while
684  * attempting to allocate blocks.  If there's     634  * attempting to allocate blocks.  If there's an indication that a pending
685  * journal transaction might free some space a    635  * journal transaction might free some space and allow another attempt to
686  * succeed, this function will wait for the cu    636  * succeed, this function will wait for the current or committing transaction
687  * to complete and then return TRUE.              637  * to complete and then return TRUE.
688  */                                               638  */
689 int ext4_should_retry_alloc(struct super_block    639 int ext4_should_retry_alloc(struct super_block *sb, int *retries)
690 {                                                 640 {
691         struct ext4_sb_info *sbi = EXT4_SB(sb)    641         struct ext4_sb_info *sbi = EXT4_SB(sb);
692                                                   642 
693         if (!sbi->s_journal)                      643         if (!sbi->s_journal)
694                 return 0;                         644                 return 0;
695                                                   645 
696         if (++(*retries) > 3) {                   646         if (++(*retries) > 3) {
697                 percpu_counter_inc(&sbi->s_sra    647                 percpu_counter_inc(&sbi->s_sra_exceeded_retry_limit);
698                 return 0;                         648                 return 0;
699         }                                         649         }
700                                                   650 
701         /*                                        651         /*
702          * if there's no indication that block    652          * if there's no indication that blocks are about to be freed it's
703          * possible we just missed a transacti    653          * possible we just missed a transaction commit that did so
704          */                                       654          */
705         smp_mb();                                 655         smp_mb();
706         if (sbi->s_mb_free_pending == 0) {        656         if (sbi->s_mb_free_pending == 0) {
707                 if (test_opt(sb, DISCARD)) {      657                 if (test_opt(sb, DISCARD)) {
708                         atomic_inc(&sbi->s_ret    658                         atomic_inc(&sbi->s_retry_alloc_pending);
709                         flush_work(&sbi->s_dis    659                         flush_work(&sbi->s_discard_work);
710                         atomic_dec(&sbi->s_ret    660                         atomic_dec(&sbi->s_retry_alloc_pending);
711                 }                                 661                 }
712                 return ext4_has_free_clusters(    662                 return ext4_has_free_clusters(sbi, 1, 0);
713         }                                         663         }
714                                                   664 
715         /*                                        665         /*
716          * it's possible we've just missed a t    666          * it's possible we've just missed a transaction commit here,
717          * so ignore the returned status          667          * so ignore the returned status
718          */                                       668          */
719         ext4_debug("%s: retrying operation aft !! 669         jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
720         (void) jbd2_journal_force_commit_neste    670         (void) jbd2_journal_force_commit_nested(sbi->s_journal);
721         return 1;                                 671         return 1;
722 }                                                 672 }
723                                                   673 
724 /*                                                674 /*
725  * ext4_new_meta_blocks() -- allocate block fo    675  * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks
726  *                                                676  *
727  * @handle:             handle to this transac    677  * @handle:             handle to this transaction
728  * @inode:              file inode                678  * @inode:              file inode
729  * @goal:               given target block(fil    679  * @goal:               given target block(filesystem wide)
730  * @count:              pointer to total numbe    680  * @count:              pointer to total number of clusters needed
731  * @errp:               error code                681  * @errp:               error code
732  *                                                682  *
733  * Return 1st allocated block number on succes    683  * Return 1st allocated block number on success, *count stores total account
734  * error stores in errp pointer                   684  * error stores in errp pointer
735  */                                               685  */
736 ext4_fsblk_t ext4_new_meta_blocks(handle_t *ha    686 ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
737                                   ext4_fsblk_t    687                                   ext4_fsblk_t goal, unsigned int flags,
738                                   unsigned lon    688                                   unsigned long *count, int *errp)
739 {                                                 689 {
740         struct ext4_allocation_request ar;        690         struct ext4_allocation_request ar;
741         ext4_fsblk_t ret;                         691         ext4_fsblk_t ret;
742                                                   692 
743         memset(&ar, 0, sizeof(ar));               693         memset(&ar, 0, sizeof(ar));
744         /* Fill with neighbour allocated block    694         /* Fill with neighbour allocated blocks */
745         ar.inode = inode;                         695         ar.inode = inode;
746         ar.goal = goal;                           696         ar.goal = goal;
747         ar.len = count ? *count : 1;              697         ar.len = count ? *count : 1;
748         ar.flags = flags;                         698         ar.flags = flags;
749                                                   699 
750         ret = ext4_mb_new_blocks(handle, &ar,     700         ret = ext4_mb_new_blocks(handle, &ar, errp);
751         if (count)                                701         if (count)
752                 *count = ar.len;                  702                 *count = ar.len;
753         /*                                        703         /*
754          * Account for the allocated meta bloc    704          * Account for the allocated meta blocks.  We will never
755          * fail EDQUOT for metdata, but we do     705          * fail EDQUOT for metdata, but we do account for it.
756          */                                       706          */
757         if (!(*errp) && (flags & EXT4_MB_DELAL    707         if (!(*errp) && (flags & EXT4_MB_DELALLOC_RESERVED)) {
758                 dquot_alloc_block_nofail(inode    708                 dquot_alloc_block_nofail(inode,
759                                 EXT4_C2B(EXT4_    709                                 EXT4_C2B(EXT4_SB(inode->i_sb), ar.len));
760         }                                         710         }
761         return ret;                               711         return ret;
762 }                                                 712 }
763                                                   713 
764 /**                                               714 /**
765  * ext4_count_free_clusters() -- count filesys    715  * ext4_count_free_clusters() -- count filesystem free clusters
766  * @sb:         superblock                        716  * @sb:         superblock
767  *                                                717  *
768  * Adds up the number of free clusters from ea    718  * Adds up the number of free clusters from each block group.
769  */                                               719  */
770 ext4_fsblk_t ext4_count_free_clusters(struct s    720 ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb)
771 {                                                 721 {
772         ext4_fsblk_t desc_count;                  722         ext4_fsblk_t desc_count;
773         struct ext4_group_desc *gdp;              723         struct ext4_group_desc *gdp;
774         ext4_group_t i;                           724         ext4_group_t i;
775         ext4_group_t ngroups = ext4_get_groups    725         ext4_group_t ngroups = ext4_get_groups_count(sb);
776         struct ext4_group_info *grp;              726         struct ext4_group_info *grp;
777 #ifdef EXT4FS_DEBUG                               727 #ifdef EXT4FS_DEBUG
778         struct ext4_super_block *es;              728         struct ext4_super_block *es;
779         ext4_fsblk_t bitmap_count;                729         ext4_fsblk_t bitmap_count;
780         unsigned int x;                           730         unsigned int x;
781         struct buffer_head *bitmap_bh = NULL;     731         struct buffer_head *bitmap_bh = NULL;
782                                                   732 
783         es = EXT4_SB(sb)->s_es;                   733         es = EXT4_SB(sb)->s_es;
784         desc_count = 0;                           734         desc_count = 0;
785         bitmap_count = 0;                         735         bitmap_count = 0;
786         gdp = NULL;                               736         gdp = NULL;
787                                                   737 
788         for (i = 0; i < ngroups; i++) {           738         for (i = 0; i < ngroups; i++) {
789                 gdp = ext4_get_group_desc(sb,     739                 gdp = ext4_get_group_desc(sb, i, NULL);
790                 if (!gdp)                         740                 if (!gdp)
791                         continue;                 741                         continue;
792                 grp = NULL;                       742                 grp = NULL;
793                 if (EXT4_SB(sb)->s_group_info)    743                 if (EXT4_SB(sb)->s_group_info)
794                         grp = ext4_get_group_i    744                         grp = ext4_get_group_info(sb, i);
795                 if (!grp || !EXT4_MB_GRP_BBITM    745                 if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
796                         desc_count += ext4_fre    746                         desc_count += ext4_free_group_clusters(sb, gdp);
797                 brelse(bitmap_bh);                747                 brelse(bitmap_bh);
798                 bitmap_bh = ext4_read_block_bi    748                 bitmap_bh = ext4_read_block_bitmap(sb, i);
799                 if (IS_ERR(bitmap_bh)) {          749                 if (IS_ERR(bitmap_bh)) {
800                         bitmap_bh = NULL;         750                         bitmap_bh = NULL;
801                         continue;                 751                         continue;
802                 }                                 752                 }
803                                                   753 
804                 x = ext4_count_free(bitmap_bh-    754                 x = ext4_count_free(bitmap_bh->b_data,
805                                     EXT4_CLUST    755                                     EXT4_CLUSTERS_PER_GROUP(sb) / 8);
806                 printk(KERN_DEBUG "group %u: s    756                 printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n",
807                         i, ext4_free_group_clu    757                         i, ext4_free_group_clusters(sb, gdp), x);
808                 bitmap_count += x;                758                 bitmap_count += x;
809         }                                         759         }
810         brelse(bitmap_bh);                        760         brelse(bitmap_bh);
811         printk(KERN_DEBUG "ext4_count_free_clu    761         printk(KERN_DEBUG "ext4_count_free_clusters: stored = %llu"
812                ", computed = %llu, %llu\n",       762                ", computed = %llu, %llu\n",
813                EXT4_NUM_B2C(EXT4_SB(sb), ext4_    763                EXT4_NUM_B2C(EXT4_SB(sb), ext4_free_blocks_count(es)),
814                desc_count, bitmap_count);         764                desc_count, bitmap_count);
815         return bitmap_count;                      765         return bitmap_count;
816 #else                                             766 #else
817         desc_count = 0;                           767         desc_count = 0;
818         for (i = 0; i < ngroups; i++) {           768         for (i = 0; i < ngroups; i++) {
819                 gdp = ext4_get_group_desc(sb,     769                 gdp = ext4_get_group_desc(sb, i, NULL);
820                 if (!gdp)                         770                 if (!gdp)
821                         continue;                 771                         continue;
822                 grp = NULL;                       772                 grp = NULL;
823                 if (EXT4_SB(sb)->s_group_info)    773                 if (EXT4_SB(sb)->s_group_info)
824                         grp = ext4_get_group_i    774                         grp = ext4_get_group_info(sb, i);
825                 if (!grp || !EXT4_MB_GRP_BBITM    775                 if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp))
826                         desc_count += ext4_fre    776                         desc_count += ext4_free_group_clusters(sb, gdp);
827         }                                         777         }
828                                                   778 
829         return desc_count;                        779         return desc_count;
830 #endif                                            780 #endif
831 }                                                 781 }
832                                                   782 
833 static inline int test_root(ext4_group_t a, in    783 static inline int test_root(ext4_group_t a, int b)
834 {                                                 784 {
835         while (1) {                               785         while (1) {
836                 if (a < b)                        786                 if (a < b)
837                         return 0;                 787                         return 0;
838                 if (a == b)                       788                 if (a == b)
839                         return 1;                 789                         return 1;
840                 if ((a % b) != 0)                 790                 if ((a % b) != 0)
841                         return 0;                 791                         return 0;
842                 a = a / b;                        792                 a = a / b;
843         }                                         793         }
844 }                                                 794 }
845                                                   795 
846 /**                                               796 /**
847  *      ext4_bg_has_super - number of blocks u    797  *      ext4_bg_has_super - number of blocks used by the superblock in group
848  *      @sb: superblock for filesystem            798  *      @sb: superblock for filesystem
849  *      @group: group number to check             799  *      @group: group number to check
850  *                                                800  *
851  *      Return the number of blocks used by th    801  *      Return the number of blocks used by the superblock (primary or backup)
852  *      in this group.  Currently this will be    802  *      in this group.  Currently this will be only 0 or 1.
853  */                                               803  */
854 int ext4_bg_has_super(struct super_block *sb,     804 int ext4_bg_has_super(struct super_block *sb, ext4_group_t group)
855 {                                                 805 {
856         struct ext4_super_block *es = EXT4_SB(    806         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
857                                                   807 
858         if (group == 0)                           808         if (group == 0)
859                 return 1;                         809                 return 1;
860         if (ext4_has_feature_sparse_super2(sb)    810         if (ext4_has_feature_sparse_super2(sb)) {
861                 if (group == le32_to_cpu(es->s    811                 if (group == le32_to_cpu(es->s_backup_bgs[0]) ||
862                     group == le32_to_cpu(es->s    812                     group == le32_to_cpu(es->s_backup_bgs[1]))
863                         return 1;                 813                         return 1;
864                 return 0;                         814                 return 0;
865         }                                         815         }
866         if ((group <= 1) || !ext4_has_feature_    816         if ((group <= 1) || !ext4_has_feature_sparse_super(sb))
867                 return 1;                         817                 return 1;
868         if (!(group & 1))                         818         if (!(group & 1))
869                 return 0;                         819                 return 0;
870         if (test_root(group, 3) || (test_root(    820         if (test_root(group, 3) || (test_root(group, 5)) ||
871             test_root(group, 7))                  821             test_root(group, 7))
872                 return 1;                         822                 return 1;
873                                                   823 
874         return 0;                                 824         return 0;
875 }                                                 825 }
876                                                   826 
877 static unsigned long ext4_bg_num_gdb_meta(stru    827 static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb,
878                                         ext4_g    828                                         ext4_group_t group)
879 {                                                 829 {
880         unsigned long metagroup = group / EXT4    830         unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
881         ext4_group_t first = metagroup * EXT4_    831         ext4_group_t first = metagroup * EXT4_DESC_PER_BLOCK(sb);
882         ext4_group_t last = first + EXT4_DESC_    832         ext4_group_t last = first + EXT4_DESC_PER_BLOCK(sb) - 1;
883                                                   833 
884         if (group == first || group == first +    834         if (group == first || group == first + 1 || group == last)
885                 return 1;                         835                 return 1;
886         return 0;                                 836         return 0;
887 }                                                 837 }
888                                                   838 
889 static unsigned long ext4_bg_num_gdb_nometa(st    839 static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb,
890                                         ext4_g    840                                         ext4_group_t group)
891 {                                                 841 {
892         if (!ext4_bg_has_super(sb, group))        842         if (!ext4_bg_has_super(sb, group))
893                 return 0;                         843                 return 0;
894                                                   844 
895         if (ext4_has_feature_meta_bg(sb))         845         if (ext4_has_feature_meta_bg(sb))
896                 return le32_to_cpu(EXT4_SB(sb)    846                 return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
897         else                                      847         else
898                 return EXT4_SB(sb)->s_gdb_coun    848                 return EXT4_SB(sb)->s_gdb_count;
899 }                                                 849 }
900                                                   850 
901 /**                                               851 /**
902  *      ext4_bg_num_gdb - number of blocks use    852  *      ext4_bg_num_gdb - number of blocks used by the group table in group
903  *      @sb: superblock for filesystem            853  *      @sb: superblock for filesystem
904  *      @group: group number to check             854  *      @group: group number to check
905  *                                                855  *
906  *      Return the number of blocks used by th    856  *      Return the number of blocks used by the group descriptor table
907  *      (primary or backup) in this group.  In    857  *      (primary or backup) in this group.  In the future there may be a
908  *      different number of descriptor blocks     858  *      different number of descriptor blocks in each group.
909  */                                               859  */
910 unsigned long ext4_bg_num_gdb(struct super_blo    860 unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
911 {                                                 861 {
912         unsigned long first_meta_bg =             862         unsigned long first_meta_bg =
913                         le32_to_cpu(EXT4_SB(sb    863                         le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
914         unsigned long metagroup = group / EXT4    864         unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
915                                                   865 
916         if (!ext4_has_feature_meta_bg(sb) || m    866         if (!ext4_has_feature_meta_bg(sb) || metagroup < first_meta_bg)
917                 return ext4_bg_num_gdb_nometa(    867                 return ext4_bg_num_gdb_nometa(sb, group);
918                                                   868 
919         return ext4_bg_num_gdb_meta(sb,group);    869         return ext4_bg_num_gdb_meta(sb,group);
920                                                   870 
921 }                                                 871 }
922                                                   872 
923 /*                                                873 /*
924  * This function returns the number of file sy !! 874  * This function returns the number of file system metadata clusters at
925  * the beginning of a block group, including t    875  * the beginning of a block group, including the reserved gdt blocks.
926  */                                               876  */
927 unsigned int ext4_num_base_meta_blocks(struct  !! 877 static unsigned ext4_num_base_meta_clusters(struct super_block *sb,
928                                        ext4_gr !! 878                                      ext4_group_t block_group)
929 {                                                 879 {
930         struct ext4_sb_info *sbi = EXT4_SB(sb)    880         struct ext4_sb_info *sbi = EXT4_SB(sb);
931         unsigned num;                             881         unsigned num;
932                                                   882 
933         /* Check for superblock and gdt backup    883         /* Check for superblock and gdt backups in this group */
934         num = ext4_bg_has_super(sb, block_grou    884         num = ext4_bg_has_super(sb, block_group);
935                                                   885 
936         if (!ext4_has_feature_meta_bg(sb) ||      886         if (!ext4_has_feature_meta_bg(sb) ||
937             block_group < le32_to_cpu(sbi->s_e    887             block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) *
938                           sbi->s_desc_per_bloc    888                           sbi->s_desc_per_block) {
939                 if (num) {                        889                 if (num) {
940                         num += ext4_bg_num_gdb !! 890                         num += ext4_bg_num_gdb(sb, block_group);
941                         num += le16_to_cpu(sbi    891                         num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks);
942                 }                                 892                 }
943         } else { /* For META_BG_BLOCK_GROUPS *    893         } else { /* For META_BG_BLOCK_GROUPS */
944                 num += ext4_bg_num_gdb_meta(sb !! 894                 num += ext4_bg_num_gdb(sb, block_group);
945         }                                         895         }
946         return num;                            !! 896         return EXT4_NUM_B2C(sbi, num);
947 }                                              << 
948                                                << 
949 static unsigned int ext4_num_base_meta_cluster << 
950                                                << 
951 {                                              << 
952         return EXT4_NUM_B2C(EXT4_SB(sb), ext4_ << 
953 }                                                 897 }
954                                                << 
955 /**                                               898 /**
956  *      ext4_inode_to_goal_block - return a hi    899  *      ext4_inode_to_goal_block - return a hint for block allocation
957  *      @inode: inode for block allocation        900  *      @inode: inode for block allocation
958  *                                                901  *
959  *      Return the ideal location to start all    902  *      Return the ideal location to start allocating blocks for a
960  *      newly created inode.                      903  *      newly created inode.
961  */                                               904  */
962 ext4_fsblk_t ext4_inode_to_goal_block(struct i    905 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode)
963 {                                                 906 {
964         struct ext4_inode_info *ei = EXT4_I(in    907         struct ext4_inode_info *ei = EXT4_I(inode);
965         ext4_group_t block_group;                 908         ext4_group_t block_group;
966         ext4_grpblk_t colour;                     909         ext4_grpblk_t colour;
967         int flex_size = ext4_flex_bg_size(EXT4    910         int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb));
968         ext4_fsblk_t bg_start;                    911         ext4_fsblk_t bg_start;
969         ext4_fsblk_t last_block;                  912         ext4_fsblk_t last_block;
970                                                   913 
971         block_group = ei->i_block_group;          914         block_group = ei->i_block_group;
972         if (flex_size >= EXT4_FLEX_SIZE_DIR_AL    915         if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) {
973                 /*                                916                 /*
974                  * If there are at least EXT4_    917                  * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME
975                  * block groups per flexgroup,    918                  * block groups per flexgroup, reserve the first block
976                  * group for directories and s    919                  * group for directories and special files.  Regular
977                  * files will start at the sec    920                  * files will start at the second block group.  This
978                  * tends to speed up directory    921                  * tends to speed up directory access and improves
979                  * fsck times.                    922                  * fsck times.
980                  */                               923                  */
981                 block_group &= ~(flex_size-1);    924                 block_group &= ~(flex_size-1);
982                 if (S_ISREG(inode->i_mode))       925                 if (S_ISREG(inode->i_mode))
983                         block_group++;            926                         block_group++;
984         }                                         927         }
985         bg_start = ext4_group_first_block_no(i    928         bg_start = ext4_group_first_block_no(inode->i_sb, block_group);
986         last_block = ext4_blocks_count(EXT4_SB    929         last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1;
987                                                   930 
988         /*                                        931         /*
989          * If we are doing delayed allocation,    932          * If we are doing delayed allocation, we don't need take
990          * colour into account.                   933          * colour into account.
991          */                                       934          */
992         if (test_opt(inode->i_sb, DELALLOC))      935         if (test_opt(inode->i_sb, DELALLOC))
993                 return bg_start;                  936                 return bg_start;
994                                                   937 
995         if (bg_start + EXT4_BLOCKS_PER_GROUP(i    938         if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block)
996                 colour = (task_pid_nr(current)    939                 colour = (task_pid_nr(current) % 16) *
997                         (EXT4_BLOCKS_PER_GROUP    940                         (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
998         else                                      941         else
999                 colour = (task_pid_nr(current)    942                 colour = (task_pid_nr(current) % 16) *
1000                         ((last_block - bg_sta    943                         ((last_block - bg_start) / 16);
1001         return bg_start + colour;                944         return bg_start + colour;
1002 }                                                945 }
1003                                                  946 
1004                                                  947 

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