diff options
| -rw-r--r-- | fs/cifs/cifsfs.c | 24 | ||||
| -rw-r--r-- | fs/cifs/cifsfs.h | 4 | ||||
| -rw-r--r-- | fs/cifs/file.c | 6 |
3 files changed, 33 insertions, 1 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 1a052c0eee8..054b90b682a 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) { diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index 7163419cecd..0e32c3446ce 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -41,6 +41,10 @@ extern struct file_system_type cifs_fs_type; extern const struct address_space_operations cifs_addr_ops; extern const struct address_space_operations cifs_addr_ops_smallbuf; +/* Functions related to super block operations */ +extern void cifs_sb_active(struct super_block *sb); +extern void cifs_sb_deactive(struct super_block *sb); + /* Functions related to inodes */ extern const struct inode_operations cifs_dir_inode_ops; extern struct inode *cifs_root_iget(struct super_block *); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 8c0d8557731..7a0dd99e450 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -300,6 +300,8 @@ cifs_new_fileinfo(struct cifs_fid *fid, struct file *file, INIT_WORK(&cfile->oplock_break, cifs_oplock_break); mutex_init(&cfile->fh_mutex); + cifs_sb_active(inode->i_sb); + /* * If the server returned a read oplock and we have mandatory brlocks, * set oplock level to None. @@ -349,7 +351,8 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file) struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink); struct TCP_Server_Info *server = tcon->ses->server; struct cifsInodeInfo *cifsi = CIFS_I(inode); - struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); + struct super_block *sb = inode->i_sb; + struct cifs_sb_info *cifs_sb = CIFS_SB(sb); struct cifsLockInfo *li, *tmp; struct cifs_fid fid; struct cifs_pending_open open; @@ -414,6 +417,7 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file) cifs_put_tlink(cifs_file->tlink); dput(cifs_file->dentry); + cifs_sb_deactive(sb); kfree(cifs_file); } |