nvme: determine io_queue_size at startup

Add a transport callback to return the maximum queue size, and enforce
it in the generic nvme_ctrlr layer.

This allows the user to tell what io_queue_size was actually selected by
the transport via the ctrlr_opts returned during attach_cb.

Change-Id: I8a51332cc01c6655e2a3a171bb92877fe48ea267
Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>

lib/nvme/nvme_ctrlr.c

@@ -1307,9 +1307,14 @@ nvme_ctrlr_construct(struct spdk_nvme_ctrlr *ctrlr)
 void
 nvme_ctrlr_init_cap(struct spdk_nvme_ctrlr *ctrlr, const union spdk_nvme_cap_register *cap)
 {
+	uint32_t max_io_queue_size = nvme_transport_ctrlr_get_max_io_queue_size(ctrlr);
+
 	ctrlr->cap = *cap;
 
 	ctrlr->min_page_size = 1u << (12 + ctrlr->cap.bits.mpsmin);
+
+	ctrlr->opts.io_queue_size = nvme_min(ctrlr->opts.io_queue_size, ctrlr->cap.bits.mqes + 1u);
+	ctrlr->opts.io_queue_size = nvme_min(ctrlr->opts.io_queue_size, max_io_queue_size);
 }
 
 void

lib/nvme/nvme_internal.h

@@ -577,6 +577,7 @@ void	nvme_qpair_print_completion(struct spdk_nvme_qpair *qpair, struct spdk_nvme
 	int nvme_ ## name ## _ctrlr_get_reg_4(struct spdk_nvme_ctrlr *ctrlr, uint32_t offset, uint32_t *value); \
 	int nvme_ ## name ## _ctrlr_get_reg_8(struct spdk_nvme_ctrlr *ctrlr, uint32_t offset, uint64_t *value); \
 	uint32_t nvme_ ## name ## _ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr); \
+	uint32_t nvme_ ## name ## _ctrlr_get_max_io_queue_size(struct spdk_nvme_ctrlr *ctrlr); \
 	struct spdk_nvme_qpair *nvme_ ## name ## _ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid, enum spdk_nvme_qprio qprio); \
 	int nvme_ ## name ## _ctrlr_delete_io_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair); \
 	int nvme_ ## name ## _ctrlr_reinit_io_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair); \

lib/nvme/nvme_pcie.c

@@ -359,6 +359,12 @@ nvme_pcie_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
 	return NVME_MAX_XFER_SIZE;
 }
 
+uint32_t
+nvme_pcie_ctrlr_get_max_io_queue_size(struct spdk_nvme_ctrlr *ctrlr)
+{
+	return NVME_IO_ENTRIES;
+}
+
 static void
 nvme_pcie_ctrlr_map_cmb(struct nvme_pcie_ctrlr *pctrlr)
 {
@@ -1321,7 +1327,6 @@ nvme_pcie_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
 {
 	struct nvme_pcie_qpair *pqpair;
 	struct spdk_nvme_qpair *qpair;
-	uint32_t num_entries;
 	int rc;
 
 	assert(ctrlr != NULL);
@@ -1333,15 +1338,7 @@ nvme_pcie_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
 
 	qpair = &pqpair->qpair;
 
-	/*
+	rc = nvme_qpair_construct(qpair, qid, ctrlr->opts.io_queue_size, ctrlr, qprio);
-	 * NVMe spec sets a hard limit of 64K max entries, but
-	 *  devices may specify a smaller limit, so we need to check
-	 *  the MQES field in the capabilities register.
-	 */
-	num_entries = nvme_min(NVME_IO_ENTRIES, ctrlr->cap.bits.mqes + 1);
-	num_entries = nvme_min(num_entries, ctrlr->opts.io_queue_size);
-
-	rc = nvme_qpair_construct(qpair, qid, num_entries, ctrlr, qprio);
 	if (rc != 0) {
 		nvme_pcie_qpair_destroy(qpair);
 		return NULL;

lib/nvme/nvme_rdma.c

@@ -970,12 +970,9 @@ nvme_rdma_ctrlr_create_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
 {
 	struct nvme_rdma_qpair *rqpair;
 	struct spdk_nvme_qpair *qpair;
-	struct nvme_rdma_ctrlr *rctrlr;
 	uint32_t num_entries;
 	int rc;
 
-	rctrlr = nvme_rdma_ctrlr(ctrlr);
-
 	rqpair = calloc(1, sizeof(struct nvme_rdma_qpair));
 	if (!rqpair) {
 		SPDK_ERRLOG("failed to get create rqpair\n");
@@ -989,9 +986,7 @@ nvme_rdma_ctrlr_create_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
 		num_entries = SPDK_NVMF_MIN_ADMIN_QUEUE_ENTRIES;
 		ctrlr->adminq = qpair;
 	} else {
-		num_entries = nvme_min(NVME_HOST_MAX_ENTRIES_PER_QUEUE,
+		num_entries = ctrlr->opts.io_queue_size;
-				       ctrlr->cap.bits.mqes + 1);
-		num_entries = nvme_min(num_entries, rctrlr->ctrlr.opts.io_queue_size);
 	}
 
 	rc = nvme_qpair_construct(qpair, qid, num_entries, ctrlr, qprio);
@@ -1510,3 +1505,9 @@ nvme_rdma_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
 	/* Todo, which should get from the NVMF target */
 	return NVME_RDMA_RW_BUFFER_SIZE;
 }
+
+uint32_t
+nvme_rdma_ctrlr_get_max_io_queue_size(struct spdk_nvme_ctrlr *ctrlr)
+{
+	return NVME_HOST_MAX_ENTRIES_PER_QUEUE;
+}

lib/nvme/nvme_transport.c

@@ -153,6 +153,12 @@ nvme_transport_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
 	NVME_TRANSPORT_CALL(ctrlr->trid.trtype, ctrlr_get_max_xfer_size, (ctrlr));
 }
 
+uint32_t
+nvme_transport_ctrlr_get_max_io_queue_size(struct spdk_nvme_ctrlr *ctrlr)
+{
+	NVME_TRANSPORT_CALL(ctrlr->trid.trtype, ctrlr_get_max_io_queue_size, (ctrlr));
+}
+
 struct spdk_nvme_qpair *
 nvme_transport_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
 				     enum spdk_nvme_qprio qprio)

test/lib/nvme/unit/nvme_ctrlr_c/nvme_ctrlr_ut.c

@@ -123,6 +123,12 @@ nvme_transport_ctrlr_get_max_xfer_size(struct spdk_nvme_ctrlr *ctrlr)
 	return UINT32_MAX;
 }
 
+uint32_t
+nvme_transport_ctrlr_get_max_io_queue_size(struct spdk_nvme_ctrlr *ctrlr)
+{
+	return SPDK_NVME_IO_QUEUE_MAX_ENTRIES;
+}
+
 struct spdk_nvme_qpair *
 nvme_transport_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr, uint16_t qid,
 				     enum spdk_nvme_qprio qprio)