[PATCH RFC 1/8] nvme: Add CDQ command definitions for contiguous PRPs

[Joel Granados <joel.granados@kernel.org>]

Add nvme_cdq to the nvme_command union that handles creation and
deletion operations. NVME_FEAT_CDQ is added to the feature flags with a
value of 0x21. nvme_admin_cdq is added to the NVME opcodes with a value
of 0x45. Add support for contiguous PRPs only; the non-contiguous case
described in the NVME spec can be added later.

Signed-off-by: Joel Granados <joel.granados@kernel.org>
---
 drivers/nvme/host/core.c |  1 +
 include/linux/nvme.h     | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 6b04473c0ab73c61e208bb8fc230c2f9b65c69bc..7be6b42a1adcc3fdb3cec2e2d0e73fcf74244590 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -5133,6 +5133,7 @@ static inline void _nvme_check_size(void)
 	BUILD_BUG_ON(sizeof(struct nvme_rotational_media_log) != 512);
 	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_directive_cmd) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_cdq) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_feat_host_behavior) != 512);
 }
 
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 2479ed10f53e37055973ea3c899060913923fa62..a2012ec00e60c2f0de1b06599ba39481eebe4263 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -1240,6 +1240,7 @@ enum nvme_admin_opcode {
 	nvme_admin_virtual_mgmt		= 0x1c,
 	nvme_admin_nvme_mi_send		= 0x1d,
 	nvme_admin_nvme_mi_recv		= 0x1e,
+	nvme_admin_cdq			= 0x45,
 	nvme_admin_dbbuf		= 0x7C,
 	nvme_admin_format_nvm		= 0x80,
 	nvme_admin_security_send	= 0x81,
@@ -1309,6 +1310,7 @@ enum {
 	NVME_FEAT_PLM_WINDOW	= 0x14,
 	NVME_FEAT_HOST_BEHAVIOR	= 0x16,
 	NVME_FEAT_SANITIZE	= 0x17,
+	NVME_FEAT_CDQ		= 0x21,
 	NVME_FEAT_SW_PROGRESS	= 0x80,
 	NVME_FEAT_HOST_ID	= 0x81,
 	NVME_FEAT_RESV_MASK	= 0x82,
@@ -1514,6 +1516,33 @@ struct nvme_directive_cmd {
 	__u32			rsvd16[3];
 };
 
+struct nvme_cdq {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[5];
+	__le64			prp1;
+	__u32			rsvd8[2];
+#define NVME_CDQ_SEL_CREATE_CDQ	0x0
+#define NVME_CDQ_SEL_DELETE_CDQ	0x1
+	__u8			sel;
+	__u8			rsvd10;
+	__le16			mos;
+	union {
+		struct {
+#define NVME_CDQ_CFG_PC_CONT	(1 << 0)
+			__le16	cdq_flags;
+			__le16	cqs;
+		} create;
+		struct {
+			__le16	cdqid;
+			__le16	rsvd;
+		} delete;
+	};
+	__le32			cdqsize;
+	__u32			rsvd13[2];
+};
+
 /*
  * Fabrics subcommands.
  */
@@ -1923,6 +1952,7 @@ struct nvme_command {
 		struct nvmf_auth_receive_command auth_receive;
 		struct nvme_dbbuf dbbuf;
 		struct nvme_directive_cmd directive;
+		struct nvme_cdq cdq;
 	};
 };
 

-- 
2.47.2