fuse: fix hang of single threaded fuseblk filesystem
Single threaded NTFS-3G could get stuck if a delayed RELEASE reply
triggered a DESTROY request via path_put().
Fix this by
a) making RELEASE requests synchronous, whenever possible, on fuseblk
filesystems
b) if not possible (triggered by an asynchronous read/write) then do
the path_put() in a separate thread with schedule_work().
Reported-by: Oliver Neukum <oneukum@suse.de>
Cc: stable@kernel.org
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index ae5744a..d428694 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -21,6 +21,7 @@
#include <linux/rwsem.h>
#include <linux/rbtree.h>
#include <linux/poll.h>
+#include <linux/workqueue.h>
/** Max number of pages that can be used in a single read request */
#define FUSE_MAX_PAGES_PER_REQ 32
@@ -262,7 +263,10 @@
/** Data for asynchronous requests */
union {
struct {
- struct fuse_release_in in;
+ union {
+ struct fuse_release_in in;
+ struct work_struct work;
+ };
struct path path;
} release;
struct fuse_init_in init_in;