Commit 21ea2901 authored by Ben Walker's avatar Ben Walker Committed by Daniel Verkamp
Browse files

nvmf: cntlid is now only unique within a subsystem 



Previously we made cntlid globally unique as part of
a strategy for scaling connections that never panned
out. Now, we have a new strategy and don't need cntlid
to be globally unique, so relax the restrictions
and simplify the code.

Change-Id: I167772f5e7d37183715bf9967b0102529144bb2b
Signed-off-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-on: https://review.gerrithub.io/376250


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent b0a80710

lib/nvmf/ctrlr.c

+2 −2
Original line number Diff line number Diff line
@@ -80,8 +80,8 @@ spdk_nvmf_ctrlr_create(struct spdk_nvmf_subsystem *subsystem, 
		return NULL;

	}



	ctrlr->cntlid = spdk_nvmf_tgt_gen_cntlid(tgt);

	if (ctrlr->cntlid == 0) {

	ctrlr->cntlid = spdk_nvmf_subsystem_gen_cntlid(subsystem);

	if (ctrlr->cntlid == 0xFFFF) {

		/* Unable to get a cntlid */

		SPDK_ERRLOG("Reached max simultaneous ctrlrs\n");

		spdk_nvmf_poll_group_destroy(ctrlr->group);

lib/nvmf/nvmf.c

+0 −42
Original line number Diff line number Diff line
@@ -164,48 +164,6 @@ spdk_nvmf_tgt_find_subsystem(struct spdk_nvmf_tgt *tgt, const char *subnqn) 
	return NULL;

}



uint16_t

spdk_nvmf_tgt_gen_cntlid(struct spdk_nvmf_tgt *tgt)

{

	struct spdk_nvmf_subsystem *subsystem;

	struct spdk_nvmf_ctrlr *ctrlr;

	uint16_t count;



	/*

	 * In the worst case, we might have to try all CNTLID values between 1 and 0xFFF0 - 1

	 * before we find one that is unused (or find that all values are in use).

	 */

	count = 0xFFF0 - 1;

	do {

		tgt->next_cntlid++;

		if (tgt->next_cntlid >= 0xFFF0) {

			/* The spec reserves cntlid values in the range FFF0h to FFFFh. */

			tgt->next_cntlid = 1;

		}



		/* Check if a subsystem with this cntlid currently exists. This could

		 * happen for a very long-lived ctrlr on a target with many short-lived

		 * ctrlrs, where cntlid wraps around.

		 */

		TAILQ_FOREACH(subsystem, &tgt->subsystems, entries) {

			TAILQ_FOREACH(ctrlr, &subsystem->ctrlrs, link) {

				if (ctrlr->cntlid == tgt->next_cntlid) {

					break;

				}

			}

		}



		count--;



	} while (subsystem != NULL && count > 0);



	if (count == 0) {

		return 0;

	}



	return tgt->next_cntlid;

}



struct spdk_nvmf_transport *

spdk_nvmf_tgt_get_transport(struct spdk_nvmf_tgt *tgt, enum spdk_nvme_transport_type type)

{

lib/nvmf/nvmf_internal.h

+2 −2
Original line number Diff line number Diff line
@@ -50,7 +50,6 @@ struct spdk_nvmf_tgt { 


	struct spdk_thread			*master_thread;



	uint16_t				next_cntlid;

	uint64_t				discovery_genctr;

	TAILQ_HEAD(, spdk_nvmf_subsystem)	subsystems;

	struct spdk_nvmf_discovery_log_page	*discovery_log_page;
@@ -176,6 +175,7 @@ struct spdk_nvmf_subsystem { 
	uint32_t id;

	char subnqn[SPDK_NVMF_NQN_MAX_LEN + 1];

	enum spdk_nvmf_subtype subtype;

	uint16_t next_cntlid;

	bool allow_any_host;



	struct spdk_nvmf_tgt			*tgt;
@@ -196,7 +196,6 @@ struct spdk_nvmf_subsystem { 
	TAILQ_ENTRY(spdk_nvmf_subsystem)	entries;

};



uint16_t spdk_nvmf_tgt_gen_cntlid(struct spdk_nvmf_tgt *tgt);

struct spdk_nvmf_transport *spdk_nvmf_tgt_get_transport(struct spdk_nvmf_tgt *tgt,

		enum spdk_nvme_transport_type);
@@ -241,6 +240,7 @@ int spdk_nvmf_bdev_ctrlr_identify_ns(struct spdk_bdev *bdev, struct spdk_nvme_ns 


int spdk_nvmf_subsystem_bdev_attach(struct spdk_nvmf_subsystem *subsystem);

void spdk_nvmf_subsystem_bdev_detach(struct spdk_nvmf_subsystem *subsystem);

uint16_t spdk_nvmf_subsystem_gen_cntlid(struct spdk_nvmf_subsystem *subsystem);



static inline struct spdk_nvmf_ns *

_spdk_nvmf_subsystem_get_ns(struct spdk_nvmf_subsystem *subsystem, uint32_t nsid)

lib/nvmf/subsystem.c

+40 −0
Original line number Diff line number Diff line
@@ -117,6 +117,7 @@ spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt, 
	subsystem->subtype = type;

	subsystem->max_nsid = num_ns;

	subsystem->num_allocated_nsid = 0;

	subsystem->next_cntlid = 0;

	snprintf(subsystem->subnqn, sizeof(subsystem->subnqn), "%s", nqn);

	TAILQ_INIT(&subsystem->listeners);

	TAILQ_INIT(&subsystem->hosts);
@@ -495,3 +496,42 @@ spdk_nvmf_subsystem_get_type(struct spdk_nvmf_subsystem *subsystem) 
{

	return subsystem->subtype;

}



uint16_t

spdk_nvmf_subsystem_gen_cntlid(struct spdk_nvmf_subsystem *subsystem)

{

	struct spdk_nvmf_ctrlr *ctrlr;

	uint16_t count;

	bool in_use = true;



	/*

	 * In the worst case, we might have to try all CNTLID values between 1 and 0xFFF0 - 1

	 * before we find one that is unused (or find that all values are in use).

	 */

	count = 0xFFF0 - 1;

	do {

		subsystem->next_cntlid++;

		if (subsystem->next_cntlid >= 0xFFF0) {

			/* The spec reserves cntlid values in the range FFF0h to FFFFh. */

			subsystem->next_cntlid = 1;

		}



		/* Check if a controller with this cntlid currently exists. */

		in_use = false;

		TAILQ_FOREACH(ctrlr, &subsystem->ctrlrs, link) {

			if (ctrlr->cntlid == subsystem->next_cntlid) {

				in_use = true;

				break;

			}

		}



		count--;

	} while (in_use && count > 0);



	if (count == 0) {

		/* All valid cntlid values are in use. */

		return 0xFFFF;

	}



	return subsystem->next_cntlid;

}

test/unit/lib/nvmf/ctrlr.c/ctrlr_ut.c

+6 −6
Original line number Diff line number Diff line
@@ -45,12 +45,6 @@ spdk_nvmf_tgt_find_subsystem(struct spdk_nvmf_tgt *tgt, const char *subnqn) 
	return NULL;

}



uint16_t

spdk_nvmf_tgt_gen_cntlid(struct spdk_nvmf_tgt *tgt)

{

	return 0;

}



const struct spdk_nvme_ctrlr_data *

spdk_nvme_ctrlr_get_data(struct spdk_nvme_ctrlr *ctrlr)

{
@@ -121,6 +115,12 @@ spdk_nvmf_subsystem_get_next_ns(struct spdk_nvmf_subsystem *subsystem, struct sp 
	return NULL;

}



uint16_t

spdk_nvmf_subsystem_gen_cntlid(struct spdk_nvmf_subsystem *subsystem)

{

	return 0;

}



bool

spdk_nvmf_ctrlr_dsm_supported(struct spdk_nvmf_ctrlr *ctrlr)

{