block: simplify direct io validity check

The block layer checks all the segments for validity later, so no need
for an early check. Just reduce it to a simple position and total length
check, and defer the more invasive segment checks to the block layer.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/fops.c b/block/fops.c
index d136fb5f6b6ab7e1d5fefd6fd741fe9cf3437b2a..19814bddd77e2703eb177513f46b954e263cf8ca 100644 (file)
--- a/block/fops.c
+++ b/block/fops.c
@@ -38,8 +38,8 @@ static blk_opf_t dio_bio_write_op(struct kiocb *iocb)
 static bool blkdev_dio_invalid(struct block_device *bdev, struct kiocb *iocb,
                                struct iov_iter *iter)
 {
-       return iocb->ki_pos & (bdev_logical_block_size(bdev) - 1) ||
-               !bdev_iter_is_aligned(bdev, iter);
+       return (iocb->ki_pos | iov_iter_count(iter)) &
+                       (bdev_logical_block_size(bdev) - 1);
 }
 
 #define DIO_INLINE_BIO_VECS 4