Linux 4.8 compat: Fix removal of bio->bi_rw member

All users of bio->bi_rw have been replaced with compatibility wrappers.
This allows the kernel specific logic to be abstracted away, and for
each of the supported cases to be documented with the wrapper.  The
updated interfaces are as follows:

* void blk_queue_set_write_cache(struct request_queue *, bool, bool)
* boolean_t bio_is_flush(struct bio *)
* boolean_t bio_is_fua(struct bio *)
* boolean_t bio_is_discard(struct bio *)
* boolean_t bio_is_secure_erase(struct bio *)
* VDEV_WRITE_FLUSH_FUA

Signed-off-by: Brian Behlendorf <[email protected]>
Signed-off-by: Chunwei Chen <[email protected]>
Closes #4951

1 files changed, 10 insertions, 21 deletions

diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
index c25b243db..bf6d59fba 100644
--- a/module/zfs/zvol.c
+++ b/module/zfs/zvol.c
@@ -707,20 +707,16 @@ zvol_discard(struct bio *bio)
 		return (SET_ERROR(EIO));
 
 	/*
-	 * Align the request to volume block boundaries when REQ_SECURE is
-	 * available, but not requested. If we don't, then this will force
-	 * dnode_free_range() to zero out the unaligned parts, which is slow
-	 * (read-modify-write) and useless since we are not freeing any space
-	 * by doing so. Kernels that do not support REQ_SECURE (2.6.32 through
-	 * 2.6.35) will not receive this optimization.
+	 * Align the request to volume block boundaries when a secure erase is
+	 * not required.  This will prevent dnode_free_range() from zeroing out
+	 * the unaligned parts which is slow (read-modify-write) and useless
+	 * since we are not freeing any space by doing so.
 	 */
-#ifdef REQ_SECURE
-	if (!(bio->bi_rw & REQ_SECURE)) {
+	if (!bio_is_secure_erase(bio)) {
 		start = P2ROUNDUP(start, zv->zv_volblocksize);
 		end = P2ALIGN(end, zv->zv_volblocksize);
 		size = end - start;
 	}
-#endif
 
 	if (start >= end)
 		return (0);
@@ -812,7 +808,7 @@ zvol_request(struct request_queue *q, struct bio *bio)
 			goto out2;
 		}
 
-		if (bio_is_discard(bio)) {
+		if (bio_is_discard(bio) || bio_is_secure_erase(bio)) {
 			error = zvol_discard(bio);
 			goto out2;
 		}
@@ -821,14 +817,14 @@ zvol_request(struct request_queue *q, struct bio *bio)
 		 * Some requests are just for flush and nothing else.
 		 */
 		if (uio.uio_resid == 0) {
-			if (bio->bi_rw & VDEV_REQ_FLUSH)
+			if (bio_is_flush(bio))
 				zil_commit(zv->zv_zilog, ZVOL_OBJ);
 			goto out2;
 		}
 
 		error = zvol_write(zv, &uio,
-		    ((bio->bi_rw & (VDEV_REQ_FUA|VDEV_REQ_FLUSH)) ||
-		    zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS));
+		    bio_is_flush(bio) || bio_is_fua(bio) ||
+		    zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
 	} else
 		error = zvol_read(zv, &uio);
 
@@ -1290,14 +1286,7 @@ zvol_alloc(dev_t dev, const char *name)
 		goto out_kmem;
 
 	blk_queue_make_request(zv->zv_queue, zvol_request);
-
-#ifdef HAVE_BLK_QUEUE_WRITE_CACHE
-	blk_queue_write_cache(zv->zv_queue, B_TRUE, B_TRUE);
-#elif defined(HAVE_BLK_QUEUE_FLUSH)
-	blk_queue_flush(zv->zv_queue, VDEV_REQ_FLUSH | VDEV_REQ_FUA);
-#else
-	blk_queue_ordered(zv->zv_queue, QUEUE_ORDERED_DRAIN, NULL);
-#endif /* HAVE_BLK_QUEUE_FLUSH */
+	blk_queue_set_write_cache(zv->zv_queue, B_TRUE, B_TRUE);
 
 	zv->zv_disk = alloc_disk(ZVOL_MINORS);
 	if (zv->zv_disk == NULL)