fuse: no abort on interrupt

Don't set 'aborted' flag on a request if it's interrupted.  We have to wait
for the answer anyway, and this would only a very little time while copying
the reply.

This means, that write() on the fuse device will not return -ENOENT during
normal operation, only if the filesystem is aborted by a forced umount or
through the fusectl interface.

This could simplify userspace code somewhat when backward compatibility with
earlier kernel versions is not required.

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>

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index c78f60e..cc6c290 100644 (file)
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -273,28 +273,41 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
                        queue_interrupt(fc, req);
        }
 
-       if (req->force) {
-               spin_unlock(&fc->lock);
-               wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
-               spin_lock(&fc->lock);
-       } else {
+       if (!req->force) {
                sigset_t oldset;
 
                /* Only fatal signals may interrupt this */
                block_sigs(&oldset);
                wait_answer_interruptible(fc, req);
                restore_sigs(&oldset);
+
+               if (req->aborted)
+                       goto aborted;
+               if (req->state == FUSE_REQ_FINISHED)
+                       return;
+
+               /* Request is not yet in userspace, bail out */
+               if (req->state == FUSE_REQ_PENDING) {
+                       list_del(&req->list);
+                       __fuse_put_request(req);
+                       req->out.h.error = -EINTR;
+                       return;
+               }
        }
 
-       if (req->aborted)
-               goto aborted;
-       if (req->state == FUSE_REQ_FINISHED)
-               return;
+       /*
+        * Either request is already in userspace, or it was forced.
+        * Wait it out.
+        */
+       spin_unlock(&fc->lock);
+       wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
+       spin_lock(&fc->lock);
 
-       req->out.h.error = -EINTR;
-       req->aborted = 1;
+       if (!req->aborted)
+               return;
 
  aborted:
+       BUG_ON(req->state != FUSE_REQ_FINISHED);
        if (req->locked) {
                /* This is uninterruptible sleep, because data is
                   being copied to/from the buffers of req.  During
@@ -305,14 +318,6 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
                wait_event(req->waitq, !req->locked);
                spin_lock(&fc->lock);
        }
-       if (req->state == FUSE_REQ_PENDING) {
-               list_del(&req->list);
-               __fuse_put_request(req);
-       } else if (req->state == FUSE_REQ_SENT) {
-               spin_unlock(&fc->lock);
-               wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
-               spin_lock(&fc->lock);
-       }
 }
 
 static unsigned len_args(unsigned numargs, struct fuse_arg *args)