[RFC PATCH v4 3/3] nvme: add simple copy support

[SelvaKumar S]

Add support for  TP 4065a ("Simple Copy Command"), v2020.05.04
("Ratified")

For device supporting native simple copy, this implementation accepts
the payload passed from the block layer and convert payload to form
simple copy command and submit to the device.

Set the device copy limits to queue limits. By default copy_offload
is disabled.

End-to-end protection is done by setting both PRINFOR and PRINFOW
to 0.

Signed-off-by: SelvaKumar S <selvakuma.s1@xxxxxxxxxxx>
Signed-off-by: Kanchan Joshi <joshi.k@xxxxxxxxxxx>
Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx>
Signed-off-by: Javier González <javier.gonz@xxxxxxxxxxx>
---
 drivers/nvme/host/core.c | 87 ++++++++++++++++++++++++++++++++++++++++
 include/linux/nvme.h     | 43 ++++++++++++++++++--
 2 files changed, 127 insertions(+), 3 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index ce1b61519441..ea75af3e865a 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -708,6 +708,63 @@ static inline void nvme_setup_flush(struct nvme_ns *ns,
 	cmnd->common.nsid = cpu_to_le32(ns->head->ns_id);
 }
 
+static inline blk_status_t nvme_setup_copy(struct nvme_ns *ns,
+	       struct request *req, struct nvme_command *cmnd)
+{
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct nvme_copy_range *range = NULL;
+	struct blk_copy_payload *payload;
+	unsigned short nr_range = 0;
+	u16 control = 0, ssrl;
+	u32 dsmgmt = 0;
+	u64 slba;
+	int i;
+
+	payload = bio_data(req->bio);
+	nr_range = payload->copy_range;
+
+	if (req->cmd_flags & REQ_FUA)
+		control |= NVME_RW_FUA;
+
+	if (req->cmd_flags & REQ_FAILFAST_DEV)
+		control |= NVME_RW_LR;
+
+	cmnd->copy.opcode = nvme_cmd_copy;
+	cmnd->copy.nsid = cpu_to_le32(ns->head->ns_id);
+	cmnd->copy.sdlba = cpu_to_le64(blk_rq_pos(req) >> (ns->lba_shift - 9));
+
+	range = kmalloc_array(nr_range, sizeof(*range),
+			GFP_ATOMIC | __GFP_NOWARN);
+	if (!range)
+		return BLK_STS_RESOURCE;
+
+	for (i = 0; i < nr_range; i++) {
+		slba = payload->range[i].src;
+		slba = slba >> (ns->lba_shift - 9);
+
+		ssrl = payload->range[i].len;
+		ssrl = ssrl >> (ns->lba_shift - 9);
+
+		range[i].slba = cpu_to_le64(slba);
+		range[i].nlb = cpu_to_le16(ssrl - 1);
+	}
+
+	cmnd->copy.nr_range = nr_range - 1;
+
+	req->special_vec.bv_page = virt_to_page(range);
+	req->special_vec.bv_offset = offset_in_page(range);
+	req->special_vec.bv_len = sizeof(*range) * nr_range;
+	req->rq_flags |= RQF_SPECIAL_PAYLOAD;
+
+	if (ctrl->nr_streams)
+		nvme_assign_write_stream(ctrl, req, &control, &dsmgmt);
+
+	cmnd->rw.control = cpu_to_le16(control);
+	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
+
+	return BLK_STS_OK;
+}
+
 static blk_status_t nvme_setup_discard(struct nvme_ns *ns, struct request *req,
 		struct nvme_command *cmnd)
 {
@@ -890,6 +947,9 @@ blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
 	case REQ_OP_DISCARD:
 		ret = nvme_setup_discard(ns, req, cmd);
 		break;
+	case REQ_OP_COPY:
+		ret = nvme_setup_copy(ns, req, cmd);
+		break;
 	case REQ_OP_READ:
 		ret = nvme_setup_rw(ns, req, cmd, nvme_cmd_read);
 		break;
@@ -1917,6 +1977,31 @@ static void nvme_config_discard(struct gendisk *disk, struct nvme_ns *ns)
 		blk_queue_max_write_zeroes_sectors(queue, UINT_MAX);
 }
 
+static void nvme_config_copy(struct gendisk *disk, struct nvme_ns *ns,
+				       struct nvme_id_ns *id)
+{
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct request_queue *queue = disk->queue;
+
+	if (!(ctrl->oncs & NVME_CTRL_ONCS_COPY)) {
+		queue->limits.copy_offload = 0;
+		queue->limits.max_copy_sectors = 0;
+		queue->limits.max_copy_range_sectors = 0;
+		queue->limits.max_copy_nr_ranges = 0;
+		blk_queue_flag_clear(QUEUE_FLAG_COPY, queue);
+		return;
+	}
+
+	/* setting copy limits */
+	blk_queue_flag_test_and_set(QUEUE_FLAG_COPY, queue);
+	queue->limits.copy_offload = 0;
+	queue->limits.max_copy_sectors = le64_to_cpu(id->mcl) *
+		(1 << (ns->lba_shift - 9));
+	queue->limits.max_copy_range_sectors = le32_to_cpu(id->mssrl) *
+		(1 << (ns->lba_shift - 9));
+	queue->limits.max_copy_nr_ranges = id->msrc + 1;
+}
+
 static void nvme_config_write_zeroes(struct gendisk *disk, struct nvme_ns *ns)
 {
 	u64 max_blocks;
@@ -2112,6 +2197,7 @@ static void nvme_update_disk_info(struct gendisk *disk,
 	set_capacity_and_notify(disk, capacity);
 
 	nvme_config_discard(disk, ns);
+	nvme_config_copy(disk, ns, id);
 	nvme_config_write_zeroes(disk, ns);
 
 	if ((id->nsattr & NVME_NS_ATTR_RO) ||
@@ -4689,6 +4775,7 @@ static inline void _nvme_check_size(void)
 	BUILD_BUG_ON(sizeof(struct nvme_download_firmware) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_dsm_cmd) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_copy_command) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_write_zeroes_cmd) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
 	BUILD_BUG_ON(sizeof(struct nvme_get_log_page_command) != 64);
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index d92535997687..11ed72a2164d 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -289,7 +289,7 @@ struct nvme_id_ctrl {
 	__u8			nvscc;
 	__u8			nwpc;
 	__le16			acwu;
-	__u8			rsvd534[2];
+	__le16			ocfs;
 	__le32			sgls;
 	__le32			mnan;
 	__u8			rsvd544[224];
@@ -314,6 +314,7 @@ enum {
 	NVME_CTRL_ONCS_WRITE_ZEROES		= 1 << 3,
 	NVME_CTRL_ONCS_RESERVATIONS		= 1 << 5,
 	NVME_CTRL_ONCS_TIMESTAMP		= 1 << 6,
+	NVME_CTRL_ONCS_COPY			= 1 << 8,
 	NVME_CTRL_VWC_PRESENT			= 1 << 0,
 	NVME_CTRL_OACS_SEC_SUPP                 = 1 << 0,
 	NVME_CTRL_OACS_DIRECTIVES		= 1 << 5,
@@ -362,7 +363,10 @@ struct nvme_id_ns {
 	__le16			npdg;
 	__le16			npda;
 	__le16			nows;
-	__u8			rsvd74[18];
+	__le16			mssrl;
+	__le32			mcl;
+	__u8			msrc;
+	__u8			rsvd91[11];
 	__le32			anagrpid;
 	__u8			rsvd96[3];
 	__u8			nsattr;
@@ -673,6 +677,7 @@ enum nvme_opcode {
 	nvme_cmd_resv_report	= 0x0e,
 	nvme_cmd_resv_acquire	= 0x11,
 	nvme_cmd_resv_release	= 0x15,
+	nvme_cmd_copy		= 0x19,
 	nvme_cmd_zone_mgmt_send	= 0x79,
 	nvme_cmd_zone_mgmt_recv	= 0x7a,
 	nvme_cmd_zone_append	= 0x7d,
@@ -691,7 +696,8 @@ enum nvme_opcode {
 		nvme_opcode_name(nvme_cmd_resv_register),	\
 		nvme_opcode_name(nvme_cmd_resv_report),		\
 		nvme_opcode_name(nvme_cmd_resv_acquire),	\
-		nvme_opcode_name(nvme_cmd_resv_release))
+		nvme_opcode_name(nvme_cmd_resv_release),	\
+		nvme_opcode_name(nvme_cmd_copy))
 
 
 /*
@@ -863,6 +869,36 @@ struct nvme_dsm_range {
 	__le64			slba;
 };
 
+struct nvme_copy_command {
+	__u8                    opcode;
+	__u8                    flags;
+	__u16                   command_id;
+	__le32                  nsid;
+	__u64                   rsvd2;
+	__le64                  metadata;
+	union nvme_data_ptr     dptr;
+	__le64                  sdlba;
+	__u8			nr_range;
+	__u8			rsvd12;
+	__le16                  control;
+	__le16                  rsvd13;
+	__le16			dspec;
+	__le32                  ilbrt;
+	__le16                  lbat;
+	__le16                  lbatm;
+};
+
+struct nvme_copy_range {
+	__le64			rsvd0;
+	__le64			slba;
+	__le16			nlb;
+	__le16			rsvd18;
+	__le32			rsvd20;
+	__le32			eilbrt;
+	__le16			elbat;
+	__le16			elbatm;
+};
+
 struct nvme_write_zeroes_cmd {
 	__u8			opcode;
 	__u8			flags;
@@ -1400,6 +1436,7 @@ struct nvme_command {
 		struct nvme_download_firmware dlfw;
 		struct nvme_format_cmd format;
 		struct nvme_dsm_cmd dsm;
+		struct nvme_copy_command copy;
 		struct nvme_write_zeroes_cmd write_zeroes;
 		struct nvme_zone_mgmt_send_cmd zms;
 		struct nvme_zone_mgmt_recv_cmd zmr;
-- 
2.25.1