Merge tag 'for-5.9/io_uring-20200802' of git://git.kernel.dk/linux-block

[linux-2.6-microblaze.git] / fs / io_uring.c

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 6fd0b0f..2a3af95 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2962,9 +2962,12 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
 
        wpq = container_of(wait, struct wait_page_queue, wait);
 
-       ret = wake_page_match(wpq, key);
-       if (ret != 1)
-               return ret;
+       if (!wake_page_match(wpq, key))
+               return 0;
+
+       /* Stop waking things up if the page is locked again */
+       if (test_bit(key->bit_nr, &key->page->flags))
+               return -1;
 
        list_del_init(&wait->entry);
 
@@ -2984,6 +2987,28 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
        return 1;
 }
 
+static inline int kiocb_wait_page_queue_init(struct kiocb *kiocb,
+                                            struct wait_page_queue *wait,
+                                            wait_queue_func_t func,
+                                            void *data)
+{
+       /* Can't support async wakeup with polled IO */
+       if (kiocb->ki_flags & IOCB_HIPRI)
+               return -EINVAL;
+       if (kiocb->ki_filp->f_mode & FMODE_BUF_RASYNC) {
+               wait->wait.func = func;
+               wait->wait.private = data;
+               wait->wait.flags = 0;
+               INIT_LIST_HEAD(&wait->wait.entry);
+               kiocb->ki_flags |= IOCB_WAITQ;
+               kiocb->ki_waitq = wait;
+               return 0;
+       }
+
+       return -EOPNOTSUPP;
+}
+
+
 static bool io_rw_should_retry(struct io_kiocb *req)
 {
        struct kiocb *kiocb = &req->rw.kiocb;