fuse: fix reserved request wake up

Use wake_up_all instead of wake_up in put_reserved_req(), otherwise it is
possible that the right task is not woken up.

Also create a separate reserved_req_waitq in addition to the blocked_waitq,
since they fulfill totally separate functions.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 7 insertions, 2 deletions

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index ebc36f525eee..9c9e35e42bfd 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -129,7 +129,7 @@ static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
         struct fuse_file *ff = file->private_data;
 
         do {
-                wait_event(fc->blocked_waitq, ff->reserved_req);
+                wait_event(fc->reserved_req_waitq, ff->reserved_req);
                 spin_lock(&fc->lock);
                 if (ff->reserved_req) {
                         req = ff->reserved_req;
@@ -155,7 +155,7 @@ static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
         fuse_request_init(req);
         BUG_ON(ff->reserved_req);
         ff->reserved_req = req;
-        wake_up(&fc->blocked_waitq);
+        wake_up_all(&fc->reserved_req_waitq);
         spin_unlock(&fc->lock);
         fput(file);
 }
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 9f4603beb9e8..95bcb433d1b4 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -289,6 +289,9 @@ struct fuse_conn {
         /** waitq for blocked connection */
         wait_queue_head_t blocked_waitq;
 
+        /** waitq for reserved requests */
+        wait_queue_head_t reserved_req_waitq;
+
         /** The next unique request id */
         u64 reqctr;
 
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 807988445685..95c8a9738ca7 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -232,6 +232,7 @@ static void fuse_put_super(struct super_block *sb)
         kill_fasync(&fc->fasync, SIGIO, POLL_IN);
         wake_up_all(&fc->waitq);
         wake_up_all(&fc->blocked_waitq);
+        wake_up_all(&fc->reserved_req_waitq);
         mutex_lock(&fuse_mutex);
         list_del(&fc->entry);
         fuse_ctl_remove_conn(fc);
@@ -410,6 +411,7 @@ static struct fuse_conn *new_conn(void)
                 atomic_set(&fc->count, 1);
                 init_waitqueue_head(&fc->waitq);
                 init_waitqueue_head(&fc->blocked_waitq);
+                init_waitqueue_head(&fc->reserved_req_waitq);
                 INIT_LIST_HEAD(&fc->pending);
                 INIT_LIST_HEAD(&fc->processing);
                 INIT_LIST_HEAD(&fc->io);