Commit 736ec496 authored by Daniel Verkamp's avatar Daniel Verkamp Committed by Gerrit Code Review
Browse files

nvme: refactor _nvme_ns_cmd_rw() 



Pull the almost-identical request splitting code for driver-assisted
striping and maximum I/O size into its own function,
_nvme_ns_cmd_split_request().

Change-Id: I3c15ac2073f8f5aec721c427199c8fb1a5d6a1fc
Signed-off-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent 766afaaa

lib/nvme/nvme_ns_cmd.c

+40 −34
Original line number Diff line number Diff line
@@ -38,6 +38,41 @@ 
 *

 */



static struct nvme_request *

_nvme_ns_cmd_rw(struct nvme_namespace *ns, void *payload, uint64_t lba,

		uint32_t lba_count, nvme_cb_fn_t cb_fn, void *cb_arg,

		uint32_t opc);



static struct nvme_request *

_nvme_ns_cmd_split_request(struct nvme_namespace *ns, void *payload,

			   uint64_t lba, uint32_t lba_count,

			   nvme_cb_fn_t cb_fn, void *cb_arg, uint32_t opc,

			   struct nvme_request *req,

			   uint32_t sectors_per_max_io, uint32_t sector_mask)

{

	uint32_t		sector_size = ns->sector_size;

	uint32_t		remaining_lba_count = lba_count;

	struct nvme_request	*child;



	while (remaining_lba_count > 0) {

		lba_count = sectors_per_max_io - (lba & sector_mask);

		lba_count = nvme_min(remaining_lba_count, lba_count);



		child = _nvme_ns_cmd_rw(ns, payload, lba, lba_count, cb_fn,

					cb_arg, opc);

		if (child == NULL) {

			nvme_free_request(req);

			return NULL;

		}

		nvme_request_add_child(req, child);

		remaining_lba_count -= lba_count;

		lba += lba_count;

		payload = (void *)((uintptr_t)payload + (lba_count * sector_size));

	}



	return req;

}



static struct nvme_request *

_nvme_ns_cmd_rw(struct nvme_namespace *ns, void *payload, uint64_t lba,

		uint32_t lba_count, nvme_cb_fn_t cb_fn, void *cb_arg,
@@ -67,41 +102,12 @@ _nvme_ns_cmd_rw(struct nvme_namespace *ns, void *payload, uint64_t lba, 
	 */

	if (sectors_per_stripe > 0 &&

	    (((lba & (sectors_per_stripe - 1)) + lba_count) > sectors_per_stripe)) {

		uint64_t		remaining_lba_count = lba_count;

		struct nvme_request	*child;



		while (remaining_lba_count > 0) {

			lba_count = sectors_per_stripe - (lba & (sectors_per_stripe - 1));

			lba_count = nvme_min(remaining_lba_count, lba_count);



			child = _nvme_ns_cmd_rw(ns, payload, lba, lba_count, cb_fn,

						cb_arg, opc);

			if (child == NULL) {

				nvme_free_request(req);

				return NULL;

			}

			nvme_request_add_child(req, child);

			remaining_lba_count -= lba_count;

			lba += lba_count;

			payload = (void *)((uintptr_t)payload + (lba_count * sector_size));

		}

		return _nvme_ns_cmd_split_request(ns, payload, lba, lba_count, cb_fn, cb_arg, opc,

						  req, sectors_per_stripe, sectors_per_stripe - 1);

	} else if (lba_count > sectors_per_max_io) {

		uint64_t		remaining_lba_count = lba_count;

		struct nvme_request	*child;



		while (remaining_lba_count > 0) {

			lba_count = nvme_min(remaining_lba_count, sectors_per_max_io);

			child = _nvme_ns_cmd_rw(ns, payload, lba, lba_count, cb_fn,

						cb_arg, opc);

			if (child == NULL) {

				nvme_free_request(req);

				return NULL;

			}

			nvme_request_add_child(req, child);

			remaining_lba_count -= lba_count;

			lba += lba_count;

			payload = (void *)((uintptr_t)payload + (lba_count * sector_size));

		}

		return _nvme_ns_cmd_split_request(ns, payload, lba, lba_count, cb_fn, cb_arg, opc,

						  req, sectors_per_max_io, 0);

	} else {

		cmd = &req->cmd;

		cmd->opc = opc;