UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

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>
This commit is contained in:
Miao Xie 2014-03-06 13:55:03 +08:00 committed by Josef Bacik
parent 31f3d255c6
commit 573bfb72f7
3 changed files with 8 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/btrfs/ctree.h
View File

@ -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

2
fs/btrfs/disk-io.c
View File

@ -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);

4
fs/btrfs/inode.c
View File

@ -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;
}