NVMe: Implement doorbell stride capability

The doorbell stride allows devices to spread out their doorbells instead
of packing them tightly.  This feature was added as part of ECN 003.

This patch also enables support for more than 512 queues :-)

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index c96ab0f5ef6f..2a2c535c8345 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -36,6 +36,7 @@ struct nvme_bar {
 };
 
 #define NVME_CAP_TIMEOUT(cap)   (((cap) >> 24) & 0xff)
+#define NVME_CAP_STRIDE(cap)    (((cap) >> 32) & 0xf)
 
 enum {
         NVME_CC_ENABLE          = 1 << 0,