afs: don't use PREPARE_WORK

PREPARE_[DELAYED_]WORK() are being phased out.  They have few users
and a nasty surprise in terms of reentrancy guarantee as workqueue
considers work items to be different if they don't have the same work
function.

afs_call->async_work is multiplexed with multiple work functions.
Introduce afs_async_workfn() which invokes afs_call->async_workfn and
always use it as the work function and update the users to set the
->async_workfn field instead of overriding the work function using
PREPARE_WORK().

It would probably be best to route this with other related updates
through the workqueue tree.

Compile tested.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-afs@lists.infradead.org

diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 6621f800812287f6f0fc27cdc7f71a2a32287af2..be75b500005d0d4f68b2d6e3855e71660016353d 100644 (file)
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -75,6 +75,7 @@ struct afs_call {
        const struct afs_call_type *type;       /* type of call */
        const struct afs_wait_mode *wait_mode;  /* completion wait mode */
        wait_queue_head_t       waitq;          /* processes awaiting completion */
+       work_func_t             async_workfn;
        struct work_struct      async_work;     /* asynchronous work processor */
        struct work_struct      work;           /* actual work processor */
        struct sk_buff_head     rx_queue;       /* received packets */

diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 8ad8c2a0703a120c2dde7f425225f1d515b13f0c..ef943df73b8cdee2c6964439b81417a9c1110b12 100644 (file)
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -644,7 +644,7 @@ static void afs_process_async_call(struct work_struct *work)
 
                /* we can't just delete the call because the work item may be
                 * queued */
-               PREPARE_WORK(&call->async_work, afs_delete_async_call);
+               call->async_workfn = afs_delete_async_call;
                queue_work(afs_async_calls, &call->async_work);
        }
 
@@ -663,6 +663,13 @@ void afs_transfer_reply(struct afs_call *call, struct sk_buff *skb)
        call->reply_size += len;
 }
 
+static void afs_async_workfn(struct work_struct *work)
+{
+       struct afs_call *call = container_of(work, struct afs_call, async_work);
+
+       call->async_workfn(work);
+}
+
 /*
  * accept the backlog of incoming calls
  */
@@ -685,7 +692,8 @@ static void afs_collect_incoming_call(struct work_struct *work)
                                return;
                        }
 
-                       INIT_WORK(&call->async_work, afs_process_async_call);
+                       call->async_workfn = afs_process_async_call;
+                       INIT_WORK(&call->async_work, afs_async_workfn);
                        call->wait_mode = &afs_async_incoming_call;
                        call->type = &afs_RXCMxxxx;
                        init_waitqueue_head(&call->waitq);