io_uring: fix issue with io_write() not always undoing sb_start_write()

This is actually an older issue, but we never used to hit the -EAGAIN
path before having done sb_start_write(). Make sure that we always call
kiocb_end_write() if we need to retry the write, so that we keep the
calls to sb_start_write() etc balanced.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/rw.c b/io_uring/rw.c
index 4d4ca63..1f4a8ff 100644 (file)
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -945,6 +945,8 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags)
                        if (rw)
                                rw->bytes_done += ret2;
 
+                       if (kiocb->ki_flags & IOCB_WRITE)
+                               kiocb_end_write(req);
                        return ret ? ret : -EAGAIN;
                }
 done:
@@ -953,7 +955,12 @@ done:
 copy_iov:
                iov_iter_restore(&s->iter, &s->iter_state);
                ret = io_setup_async_rw(req, iovec, s, false);
-               return ret ?: -EAGAIN;
+               if (!ret) {
+                       if (kiocb->ki_flags & IOCB_WRITE)
+                               kiocb_end_write(req);
+                       return -EAGAIN;
+               }
+               return ret;
        }
        /* it's reportedly faster than delegating the null check to kfree() */
        if (iovec)