diff options
Diffstat (limited to 'fs/cifs/cifsfs.c')
| -rw-r--r-- | fs/cifs/cifsfs.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 1a052c0eee8e..054b90b682a7 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -91,6 +91,30 @@ struct workqueue_struct *cifsiod_wq; __u8 cifs_client_guid[SMB2_CLIENT_GUID_SIZE]; #endif +/* + * Bumps refcount for cifs super block. + * Note that it should be only called if a referece to VFS super block is + * already held, e.g. in open-type syscalls context. Otherwise it can race with + * atomic_dec_and_test in deactivate_locked_super. + */ +void +cifs_sb_active(struct super_block *sb) +{ + struct cifs_sb_info *server = CIFS_SB(sb); + + if (atomic_inc_return(&server->active) == 1) + atomic_inc(&sb->s_active); +} + +void +cifs_sb_deactive(struct super_block *sb) +{ + struct cifs_sb_info *server = CIFS_SB(sb); + + if (atomic_dec_and_test(&server->active)) + deactivate_super(sb); +} + static int cifs_read_super(struct super_block *sb) { |