[PATCH 5/5] nvmet: implement copy support for bdev backed target

[Christoph Hellwig]

On Wed, May 21, 2025 at 03:31:07PM -0700, Keith Busch wrote:
> From: Keith Busch <kbusch at kernel.org>
> 
> The nvme block device target type does not have any particular limits on
> copy commands, so all the settings are the protocol's max.

I need this additional bit so that the host code actually see the
copy support:

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index c7317299078d..355cb67a8b74 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -734,7 +734,8 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
 	id->mnan = cpu_to_le32(NVMET_MAX_NAMESPACES);
 	id->oncs = cpu_to_le16(NVME_CTRL_ONCS_DSM |
 			NVME_CTRL_ONCS_WRITE_ZEROES |
-			NVME_CTRL_ONCS_RESERVATIONS);
+			NVME_CTRL_ONCS_RESERVATIONS |
+			NVME_CTRL_ONCS_NVMCPYS);
 
 	/* XXX: don't report vwc if the underlying device is write through */
 	id->vwc = NVME_CTRL_VWC_PRESENT;