diff options
| author | Miao Xie <miaox@cn.fujitsu.com> | 2014-03-06 13:55:03 +0800 |
|---|---|---|
| committer | Josef Bacik <jbacik@fb.com> | 2014-03-10 15:17:29 -0400 |
| commit | 573bfb72f7608eb7097d2dd036a714a6ab20cffe (patch) | |
| tree | 5434c2e82299cf22af4470fef31d3890d209a0b9 | |
| parent | 31f3d255c677073f83daa1e0671bbf2157bf8edc (diff) | |
Btrfs: fix possible empty list access when flushing the delalloc inodes
We didn't have a lock to protect the access to the delalloc inodes list, that is
we might access a empty delalloc inodes list if someone start flushing delalloc
inodes because the delalloc inodes were moved into a other list temporarily.
Fix it by wrapping the access with a lock.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
| -rw-r--r-- | fs/btrfs/ctree.h | 2 | ||||
| -rw-r--r-- | fs/btrfs/disk-io.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 4 |
3 files changed, 8 insertions, 0 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 5f4921554f0a..2a9d32e193a5 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1490,6 +1490,7 @@ struct btrfs_fs_info { */ struct list_head ordered_roots; + struct mutex delalloc_root_mutex; spinlock_t delalloc_root_lock; /* all fs/file tree roots that have delalloc inodes. */ struct list_head delalloc_roots; @@ -1805,6 +1806,7 @@ struct btrfs_root { spinlock_t root_item_lock; atomic_t refs; + struct mutex delalloc_mutex; spinlock_t delalloc_lock; /* * all of the inodes that have delalloc bytes. It is possible for diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 237b5b5a2200..d9698fda2d12 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1221,6 +1221,7 @@ static void __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize, mutex_init(&root->objectid_mutex); mutex_init(&root->log_mutex); mutex_init(&root->ordered_extent_mutex); + mutex_init(&root->delalloc_mutex); init_waitqueue_head(&root->log_writer_wait); init_waitqueue_head(&root->log_commit_wait[0]); init_waitqueue_head(&root->log_commit_wait[1]); @@ -2209,6 +2210,7 @@ int open_ctree(struct super_block *sb, spin_lock_init(&fs_info->buffer_lock); rwlock_init(&fs_info->tree_mod_log_lock); mutex_init(&fs_info->reloc_mutex); + mutex_init(&fs_info->delalloc_root_mutex); seqlock_init(&fs_info->profiles_lock); init_completion(&fs_info->kobj_unregister); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index fbaf1ac3941b..0ec876657923 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8450,6 +8450,7 @@ static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput, INIT_LIST_HEAD(&works); INIT_LIST_HEAD(&splice); + mutex_lock(&root->delalloc_mutex); spin_lock(&root->delalloc_lock); list_splice_init(&root->delalloc_inodes, &splice); while (!list_empty(&splice)) { @@ -8495,6 +8496,7 @@ static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput, list_splice_tail(&splice, &root->delalloc_inodes); spin_unlock(&root->delalloc_lock); } + mutex_unlock(&root->delalloc_mutex); return ret; } @@ -8536,6 +8538,7 @@ int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput, INIT_LIST_HEAD(&splice); + mutex_lock(&fs_info->delalloc_root_mutex); spin_lock(&fs_info->delalloc_root_lock); list_splice_init(&fs_info->delalloc_roots, &splice); while (!list_empty(&splice) && nr) { @@ -8575,6 +8578,7 @@ out: list_splice_tail(&splice, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); } + mutex_unlock(&fs_info->delalloc_root_mutex); return ret; } |