diff options
Diffstat (limited to 'fs/ext4/balloc.c')
| -rw-r--r-- | fs/ext4/balloc.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 0b202e00d93f..8fd0b3cdab4c 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -270,6 +270,7 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, ext4_group_t ngroups = ext4_get_groups_count(sb); struct ext4_group_desc *desc; struct ext4_sb_info *sbi = EXT4_SB(sb); + struct buffer_head *bh_p; if (block_group >= ngroups) { ext4_error(sb, "block_group >= groups_count - block_group = %u," @@ -280,7 +281,14 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); - if (!sbi->s_group_desc[group_desc]) { + bh_p = sbi_array_rcu_deref(sbi, s_group_desc, group_desc); + /* + * sbi_array_rcu_deref returns with rcu unlocked, this is ok since + * the pointer being dereferenced won't be dereferenced again. By + * looking at the usage in add_new_gdb() the value isn't modified, + * just the pointer, and so it remains valid. + */ + if (!bh_p) { ext4_error(sb, "Group descriptor not loaded - " "block_group = %u, group_desc = %u, desc = %u", block_group, group_desc, offset); @@ -288,10 +296,10 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, } desc = (struct ext4_group_desc *)( - (__u8 *)sbi->s_group_desc[group_desc]->b_data + + (__u8 *)bh_p->b_data + offset * EXT4_DESC_SIZE(sb)); if (bh) - *bh = sbi->s_group_desc[group_desc]; + *bh = bh_p; return desc; } @@ -371,7 +379,8 @@ static int ext4_validate_block_bitmap(struct super_block *sb, if (buffer_verified(bh)) goto verified; if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group, - desc, bh))) { + desc, bh) || + ext4_simulate_fail(sb, EXT4_SIM_BBITMAP_CRC))) { ext4_unlock_group(sb, block_group); ext4_error(sb, "bg %u: bad block bitmap checksum", block_group); ext4_mark_group_bitmap_corrupted(sb, block_group, @@ -505,7 +514,9 @@ int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group, if (!desc) return -EFSCORRUPTED; wait_on_buffer(bh); + ext4_simulate_fail_bh(sb, bh, EXT4_SIM_BBITMAP_EIO); if (!buffer_uptodate(bh)) { + ext4_set_errno(sb, EIO); ext4_error(sb, "Cannot read block bitmap - " "block_group = %u, block_bitmap = %llu", block_group, (unsigned long long) bh->b_blocknr); |