fuse: add req flag for private list

When an unlocked request is aborted, it is moved from fpq->io to a private
list.  Then, after unlocking fpq->lock, the private list is processed and
the requests are finished off.

To protect the private list, we need to mark the request with a flag, so if
in the meantime the request is unlocked the list is not corrupted.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 32e0e74e8f4d50833855e6827e2552478148c466..7f37e55edc0e9f23425d37c9c1c4fae9a12860bb 100644 (file)
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1328,7 +1328,8 @@ static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
        return reqsize;
 
 out_end:
-       list_del_init(&req->list);
+       if (!test_bit(FR_PRIVATE, &req->flags))
+               list_del_init(&req->list);
        spin_unlock(&fpq->lock);
        request_end(fc, req);
        return err;
@@ -1945,7 +1946,8 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
                err = -ENOENT;
        else if (err)
                req->out.h.error = -EIO;
-       list_del_init(&req->list);
+       if (!test_bit(FR_PRIVATE, &req->flags))
+               list_del_init(&req->list);
        spin_unlock(&fpq->lock);
        request_end(fc, req);
 
@@ -2149,8 +2151,10 @@ void fuse_abort_conn(struct fuse_conn *fc)
                        req->out.h.error = -ECONNABORTED;
                        spin_lock(&req->waitq.lock);
                        set_bit(FR_ABORTED, &req->flags);
-                       if (!test_bit(FR_LOCKED, &req->flags))
+                       if (!test_bit(FR_LOCKED, &req->flags)) {
+                               set_bit(FR_PRIVATE, &req->flags);
                                list_move(&req->list, &to_end1);
+                       }
                        spin_unlock(&req->waitq.lock);
                }
                list_splice_init(&fpq->processing, &to_end2);

diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index ad3799e57efd8519d2a162d04143ea026da1bc60..a9507fd97d5e118ea227d1e0eff4e4bec77cbfac 100644 (file)
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -269,6 +269,7 @@ struct fuse_io_priv {
  * FR_PENDING:         request is not yet in userspace
  * FR_SENT:            request is in userspace, waiting for an answer
  * FR_FINISHED:                request is finished
+ * FR_PRIVATE:         request is on private list
  */
 enum fuse_req_flag {
        FR_ISREPLY,
@@ -281,6 +282,7 @@ enum fuse_req_flag {
        FR_PENDING,
        FR_SENT,
        FR_FINISHED,
+       FR_PRIVATE,
 };
 
 /**