fs: Introduce IOMAP_NOWAIT
IOCB_NOWAIT translates to IOMAP_NOWAIT for iomaps.
This is used by XFS in the XFS patch.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/iomap.c b/fs/iomap.c
index 18f2f2b..c71a64b 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -881,6 +881,14 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
flags |= IOMAP_WRITE;
}
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (filemap_range_has_page(mapping, start, end)) {
+ ret = -EAGAIN;
+ goto out_free_dio;
+ }
+ flags |= IOMAP_NOWAIT;
+ }
+
ret = filemap_write_and_wait_range(mapping, start, end);
if (ret)
goto out_free_dio;
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index f753e78..69f4e94 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -52,6 +52,7 @@ struct iomap {
#define IOMAP_REPORT (1 << 2) /* report extent status, e.g. FIEMAP */
#define IOMAP_FAULT (1 << 3) /* mapping for page fault */
#define IOMAP_DIRECT (1 << 4) /* direct I/O */
+#define IOMAP_NOWAIT (1 << 5) /* Don't wait for writeback */
struct iomap_ops {
/*
