diff options
author | Miao Xie <miaox@cn.fujitsu.com> | 2011-03-27 08:07:36 (GMT) |
---|---|---|
committer | root <Chris Mason chris.mason@oracle.com> | 2011-03-28 09:37:58 (GMT) |
commit | 1561deda687eef0e95065f1268d680ddc5976ee7 (patch) | |
tree | 3ad8a8305fc3ca960cf7ef472f64d9cfef246ffd /fs/btrfs/inode.c | |
parent | c055e99eea6e4f614267632fac546e7896c0227b (diff) | |
download | linux-1561deda687eef0e95065f1268d680ddc5976ee7.tar.xz |
btrfs: fix possible deadlock by clearing __GFP_FS flag
Using the GFP_HIGHUSER_MOVABLE flag to allocate the metadata's page may cause
deadlock.
Task1
open()
...
btrfs_search_slot()
...
btrfs_cow_block()
...
alloc_page()
wait for reclaiming
shrink_slab()
...
shrink_icache_memory()
...
btrfs_evict_inode()
...
btrfs_search_slot()
If the path is locked by task1, the deadlock happens.
So the btree's page cache is different with the file's page cache, it can not
allocate pages by GFP_HIGHUSER_MOVABLE flag, we must clear __GFP_FS flag in
GFP_HIGHUSER_MOVABLE flag.
Reported-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/inode.c')
-rw-r--r-- | fs/btrfs/inode.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 04babaf..0627418 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2536,6 +2536,8 @@ static void btrfs_read_locked_inode(struct inode *inode) BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); alloc_group_block = btrfs_inode_block_group(leaf, inode_item); + if (location.objectid == BTRFS_FREE_SPACE_OBJECTID) + inode->i_mapping->flags &= ~__GFP_FS; /* * try to precache a NULL acl entry for files that don't have @@ -4084,7 +4086,6 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, BTRFS_I(inode)->root = root; memcpy(&BTRFS_I(inode)->location, location, sizeof(*location)); btrfs_read_locked_inode(inode); - inode_tree_add(inode); unlock_new_inode(inode); if (new) |