From c5e298ae53dc2eb69f2f7153be03454c8a33c658 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sun, 21 Jun 2015 01:25:29 -0400 Subject: [PATCH] ext4: prevent ext4_quota_write() from failing due to ENOSPC In order to prevent quota block tracking to be inaccurate when ext4_quota_write() fails with ENOSPC, we make two changes. The quota file can now use the reserved block (since the quota file is arguably file system metadata), and ext4_quota_write() now uses ext4_should_retry_alloc() to retry the block allocation after a commit has completed and released some blocks for allocation. This fixes failures of xfstests generic/270: Quota error (device vdc): write_blk: dquota write failed Quota error (device vdc): qtree_write_dquot: Error -28 occurred while creating quota Signed-off-by: Theodore Ts'o --- fs/ext4/extents.c | 2 ++ fs/ext4/indirect.c | 2 ++ fs/ext4/inode.c | 10 +++++----- fs/ext4/namei.c | 2 +- fs/ext4/super.c | 8 +++++++- 5 files changed, 17 insertions(+), 7 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 1ba8b4ab03a8..d86d2622f826 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4456,6 +4456,8 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, ar.flags |= EXT4_MB_HINT_NOPREALLOC; if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) ar.flags |= EXT4_MB_DELALLOC_RESERVED; + if (flags & EXT4_GET_BLOCKS_METADATA_NOFAIL) + ar.flags |= EXT4_MB_USE_RESERVED; newblock = ext4_mb_new_blocks(handle, &ar, &err); if (!newblock) goto out2; diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c index 958824019509..9962d577bad5 100644 --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -576,6 +576,8 @@ int ext4_ind_map_blocks(handle_t *handle, struct inode *inode, ar.flags = EXT4_MB_HINT_DATA; if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) ar.flags |= EXT4_MB_DELALLOC_RESERVED; + if (flags & EXT4_GET_BLOCKS_METADATA_NOFAIL) + ar.flags |= EXT4_MB_USE_RESERVED; ar.goal = ext4_find_goal(inode, map->m_lblk, partial); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 263a46c488c7..e8a67b8ba90c 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -731,18 +731,18 @@ int ext4_get_block(struct inode *inode, sector_t iblock, * `handle' can be NULL if create is zero */ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, - ext4_lblk_t block, int create) + ext4_lblk_t block, int map_flags) { struct ext4_map_blocks map; struct buffer_head *bh; + int create = map_flags & EXT4_GET_BLOCKS_CREATE; int err; J_ASSERT(handle != NULL || create == 0); map.m_lblk = block; map.m_len = 1; - err = ext4_map_blocks(handle, inode, &map, - create ? EXT4_GET_BLOCKS_CREATE : 0); + err = ext4_map_blocks(handle, inode, &map, map_flags); if (err == 0) return create ? ERR_PTR(-ENOSPC) : NULL; @@ -788,11 +788,11 @@ errout: } struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, - ext4_lblk_t block, int create) + ext4_lblk_t block, int map_flags) { struct buffer_head *bh; - bh = ext4_getblk(handle, inode, block, create); + bh = ext4_getblk(handle, inode, block, map_flags); if (IS_ERR(bh)) return bh; if (!bh || buffer_uptodate(bh)) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 5e7676f1e82f..e230b31251f7 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -61,7 +61,7 @@ static struct buffer_head *ext4_append(handle_t *handle, *block = inode->i_size >> inode->i_sb->s_blocksize_bits; - bh = ext4_bread(handle, inode, *block, 1); + bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); if (IS_ERR(bh)) return bh; inode->i_size += inode->i_sb->s_blocksize; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 2858ac09f5a3..bd4df9d379b2 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5438,6 +5438,7 @@ static ssize_t ext4_quota_write(struct super_block *sb, int type, struct inode *inode = sb_dqopt(sb)->files[type]; ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb); int err, offset = off & (sb->s_blocksize - 1); + int retries = 0; struct buffer_head *bh; handle_t *handle = journal_current_handle(); @@ -5458,7 +5459,12 @@ static ssize_t ext4_quota_write(struct super_block *sb, int type, return -EIO; } - bh = ext4_bread(handle, inode, blk, 1); + do { + bh = ext4_bread(handle, inode, blk, + EXT4_GET_BLOCKS_CREATE | + EXT4_GET_BLOCKS_METADATA_NOFAIL); + } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) && + ext4_should_retry_alloc(inode->i_sb, &retries)); if (IS_ERR(bh)) return PTR_ERR(bh); if (!bh)