[PATCH RFC V2 3/7] nvme-core: reserve tags for cancel commands

[Maurizio Lombardi]

If the controller supports cancel commands, reserve
NVME_RSV_CANCEL_MAX tags for them.

Signed-off-by: Maurizio Lombardi <mlombard at redhat.com>
---
 drivers/nvme/host/core.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index d1e87d74c48b..60b56404d3fb 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -4569,9 +4569,14 @@ int nvme_alloc_io_tag_set(struct nvme_ctrl *ctrl, struct blk_mq_tag_set *set,
 	 */
 	if (ctrl->quirks & NVME_QUIRK_SHARED_TAGS)
 		set->reserved_tags = NVME_AQ_DEPTH;
-	else if (ctrl->ops->flags & NVME_F_FABRICS)
+	else if (ctrl->ops->flags & NVME_F_FABRICS) {
 		/* Reserved for fabric connect */
 		set->reserved_tags = 1;
+		if (nvme_io_command_supported(ctrl, nvme_cmd_cancel)) {
+			/* Reserved for cancel commands */
+			set->reserved_tags += NVME_RSV_CANCEL_MAX;
+		}
+	}
 	set->numa_node = ctrl->numa_node;
 	set->flags = BLK_MQ_F_SHOULD_MERGE;
 	if (ctrl->ops->flags & NVME_F_BLOCKING)
-- 
2.43.5