nvmet: use IOCB_NOWAIT only if the filesystem supports it

Submit I/O requests with the IOCB_NOWAIT flag set only if
the underlying filesystem supports it.

Fixes: 50a909db36f2 ("nvmet: use IOCB_NOWAIT for file-ns buffered I/O")
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index 6aa30f3..6be6e59 100644 (file)
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -8,6 +8,7 @@
 #include <linux/uio.h>
 #include <linux/falloc.h>
 #include <linux/file.h>
+#include <linux/fs.h>
 #include "nvmet.h"
 
 #define NVMET_MAX_MPOOL_BVEC           16
@@ -266,7 +267,8 @@ static void nvmet_file_execute_rw(struct nvmet_req *req)
 
        if (req->ns->buffered_io) {
                if (likely(!req->f.mpool_alloc) &&
-                               nvmet_file_execute_io(req, IOCB_NOWAIT))
+                   (req->ns->file->f_mode & FMODE_NOWAIT) &&
+                   nvmet_file_execute_io(req, IOCB_NOWAIT))
                        return;
                nvmet_file_submit_buffered_io(req);
        } else