X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=include%2Flinux%2Fblkdev_compat.h;h=0a7c985d8ad58fcdf5598a5b2d9ee2506e32c287;hb=86f35f34f419f6eaff53b25f463c13f72186b103;hp=d2e80ec88f6123283255ba4f0c80a561474386b7;hpb=45066d1f20a582fc8229776503b1cdd554d7fde4;p=zfs.git

diff --git a/include/linux/blkdev_compat.h b/include/linux/blkdev_compat.h
index d2e80ec..0a7c985 100644
--- a/include/linux/blkdev_compat.h
+++ b/include/linux/blkdev_compat.h
@@ -172,6 +172,17 @@ __blk_rq_bytes(struct request *req)
 #define blk_fs_request(rq)	((rq)->cmd_type == REQ_TYPE_FS)
 #endif
 
+/*
+ * 2.6.27 API change,
+ * The blk_queue_stackable() queue flag was added in 2.6.27 to handle dm
+ * stacking drivers.  Prior to this request stacking drivers were detected
+ * by checking (q->request_fn == NULL), for earlier kernels we revert to
+ * this legacy behavior.
+ */
+#ifndef blk_queue_stackable
+#define blk_queue_stackable(q)	((q)->request_fn == NULL)
+#endif
+
 #ifndef HAVE_GET_DISK_RO
 static inline int
 get_disk_ro(struct gendisk *disk)
@@ -328,6 +339,20 @@ bio_set_flags_failfast(struct block_device *bdev, int *flags)
 #endif
 
 /*
+ * 2.6.37 API change
+ * The WRITE_FLUSH, WRITE_FUA, and WRITE_FLUSH_FUA flags have been
+ * introduced as a replacement for WRITE_BARRIER.  This was done to
+ * allow richer semantics to be expressed to the block layer.  It is
+ * the block layers responsibility to choose the correct way to
+ * implement these semantics.
+ */
+#ifdef WRITE_FLUSH_FUA
+# define VDEV_WRITE_FLUSH_FUA		WRITE_FLUSH_FUA
+#else
+# define VDEV_WRITE_FLUSH_FUA		WRITE_BARRIER
+#endif
+
+/*
  * Default Linux IO Scheduler,
  * Setting the scheduler to noop will allow the Linux IO scheduler to
  * still perform front and back merging, while leaving the request