text: /*-
   *   BSD LICENSE
   *
   *   Copyright (c) Intel Corporation. All rights reserved.
   *   Copyright (c) 2019, 2020 Mellanox Technologies LTD. All rights reserved.
   *
   *   Redistribution and use in source and binary forms, with or without
   *   modification, are permitted provided that the following conditions
   *   are met:
   *
   *     * Redistributions of source code must retain the above copyright
   *       notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions and the following disclaimer in
   *       the documentation and/or other materials provided with the
   *       distribution.
   *     * Neither the name of Intel Corporation nor the names of its
   *       contributors may be used to endorse or promote products derived
   *       from this software without specific prior written permission.
   *
   *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "spdk/stdinc.h"
  
  #include "nvme_internal.h"
  #include "nvme_io_msg.h"
  
  #include "spdk/env.h"
  #include "spdk/string.h"
  
  struct nvme_active_ns_ctx;
  
  static void nvme_ctrlr_destruct_namespaces(struct spdk_nvme_ctrlr *ctrlr);
  static int nvme_ctrlr_construct_and_submit_aer(struct spdk_nvme_ctrlr *ctrlr,
  		struct nvme_async_event_request *aer);
  static void nvme_ctrlr_identify_active_ns_async(struct nvme_active_ns_ctx *ctx);
  static int nvme_ctrlr_identify_ns_async(struct spdk_nvme_ns *ns);
  static int nvme_ctrlr_identify_id_desc_async(struct spdk_nvme_ns *ns);
  
  static int
  nvme_ctrlr_get_cc(struct spdk_nvme_ctrlr *ctrlr, union spdk_nvme_cc_register *cc)
  {
  	return nvme_transport_ctrlr_get_reg_4(ctrlr, offsetof(struct spdk_nvme_registers, cc.raw),
  					      &cc->raw);
  }
  
  static int
  nvme_ctrlr_get_csts(struct spdk_nvme_ctrlr *ctrlr, union spdk_nvme_csts_register *csts)
  {
  	return nvme_transport_ctrlr_get_reg_4(ctrlr, offsetof(struct spdk_nvme_registers, csts.raw),
  					      &csts->raw);
  }
  
  int
  nvme_ctrlr_get_cap(struct spdk_nvme_ctrlr *ctrlr, union spdk_nvme_cap_register *cap)
  {
  	return nvme_transport_ctrlr_get_reg_8(ctrlr, offsetof(struct spdk_nvme_registers, cap.raw),
  					      &cap->raw);
  }
  
  int
  nvme_ctrlr_get_vs(struct spdk_nvme_ctrlr *ctrlr, union spdk_nvme_vs_register *vs)
  {
  	return nvme_transport_ctrlr_get_reg_4(ctrlr, offsetof(struct spdk_nvme_registers, vs.raw),
  					      &vs->raw);
  }
  
  static int
  nvme_ctrlr_set_cc(struct spdk_nvme_ctrlr *ctrlr, const union spdk_nvme_cc_register *cc)
  {
  	return nvme_transport_ctrlr_set_reg_4(ctrlr, offsetof(struct spdk_nvme_registers, cc.raw),
  					      cc->raw);
  }
  
  int
  nvme_ctrlr_get_cmbsz(struct spdk_nvme_ctrlr *ctrlr, union spdk_nvme_cmbsz_register *cmbsz)
  {
  	return nvme_transport_ctrlr_get_reg_4(ctrlr, offsetof(struct spdk_nvme_registers, cmbsz.raw),
  					      &cmbsz->raw);
  }
  
  void
  spdk_nvme_ctrlr_get_default_ctrlr_opts(struct spdk_nvme_ctrlr_opts *opts, size_t opts_size)
  {
  	char host_id_str[SPDK_UUID_STRING_LEN];
  
  	assert(opts);
  
  	memset(opts, 0, opts_size);
  
  #define FIELD_OK(field) \
  	offsetof(struct spdk_nvme_ctrlr_opts, field) + sizeof(opts->field) <= opts_size
  
  	if (FIELD_OK(num_io_queues)) {
  		opts->num_io_queues = DEFAULT_MAX_IO_QUEUES;
  	}
  
  	if (FIELD_OK(use_cmb_sqs)) {
  		opts->use_cmb_sqs = true;
  	}
  
  	if (FIELD_OK(no_shn_notification)) {
  		opts->no_shn_notification = false;
  	}
  
  	if (FIELD_OK(arb_mechanism)) {
  		opts->arb_mechanism = SPDK_NVME_CC_AMS_RR;
  	}
  
  	if (FIELD_OK(keep_alive_timeout_ms)) {
  		opts->keep_alive_timeout_ms = MIN_KEEP_ALIVE_TIMEOUT_IN_MS;
  	}
  
  	if (FIELD_OK(transport_retry_count)) {
  		opts->transport_retry_count = SPDK_NVME_DEFAULT_RETRY_COUNT;
  	}
  
  	if (FIELD_OK(io_queue_size)) {
  		opts->io_queue_size = DEFAULT_IO_QUEUE_SIZE;
  	}
  
  	if (FIELD_OK(io_queue_requests)) {
  		opts->io_queue_requests = DEFAULT_IO_QUEUE_REQUESTS;
  	}
  
  	if (FIELD_OK(host_id)) {
  		memset(opts->host_id, 0, sizeof(opts->host_id));
  	}
  
  	if (nvme_driver_init() == 0) {
  		if (FIELD_OK(extended_host_id)) {
  			memcpy(opts->extended_host_id, &g_spdk_nvme_driver->default_extended_host_id,
  			       sizeof(opts->extended_host_id));
  		}
  
  		if (FIELD_OK(hostnqn)) {
  			spdk_uuid_fmt_lower(host_id_str, sizeof(host_id_str),
  					    &g_spdk_nvme_driver->default_extended_host_id);
  			snprintf(opts->hostnqn, sizeof(opts->hostnqn), "2014-08.org.nvmexpress:uuid:%s", host_id_str);
  		}
  	}
  
  	if (FIELD_OK(src_addr)) {
  		memset(opts->src_addr, 0, sizeof(opts->src_addr));
  	}
  
  	if (FIELD_OK(src_svcid)) {
  		memset(opts->src_svcid, 0, sizeof(opts->src_svcid));
  	}
  
  	if (FIELD_OK(command_set)) {
  		opts->command_set = SPDK_NVME_CC_CSS_NVM;
  	}
  
  	if (FIELD_OK(admin_timeout_ms)) {
  		opts->admin_timeout_ms = NVME_MAX_ADMIN_TIMEOUT_IN_SECS * 1000;
  	}
  
  	if (FIELD_OK(header_digest)) {
  		opts->header_digest = false;
  	}
  
  	if (FIELD_OK(data_digest)) {
  		opts->data_digest = false;
  	}
  
  	if (FIELD_OK(disable_error_logging)) {
  		opts->disable_error_logging = false;
  	}
  
  	if (FIELD_OK(transport_ack_timeout)) {
  		opts->transport_ack_timeout = SPDK_NVME_DEFAULT_TRANSPORT_ACK_TIMEOUT;
  	}
  
  	if (FIELD_OK(admin_queue_size)) {
  		opts->admin_queue_size = DEFAULT_ADMIN_QUEUE_SIZE;
  	}
  #undef FIELD_OK
  }
  
  /**
   * This function will be called when the process allocates the IO qpair.
   * Note: the ctrlr_lock must be held when calling this function.
   */
  static void
  nvme_ctrlr_proc_add_io_qpair(struct spdk_nvme_qpair *qpair)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  	struct spdk_nvme_ctrlr		*ctrlr = qpair->ctrlr;
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc) {
  		TAILQ_INSERT_TAIL(&active_proc->allocated_io_qpairs, qpair, per_process_tailq);
  		qpair->active_proc = active_proc;
  	}
  }
  
  /**
   * This function will be called when the process frees the IO qpair.
   * Note: the ctrlr_lock must be held when calling this function.
   */
  static void
  nvme_ctrlr_proc_remove_io_qpair(struct spdk_nvme_qpair *qpair)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  	struct spdk_nvme_ctrlr		*ctrlr = qpair->ctrlr;
  	struct spdk_nvme_qpair          *active_qpair, *tmp_qpair;
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (!active_proc) {
  		return;
  	}
  
  	TAILQ_FOREACH_SAFE(active_qpair, &active_proc->allocated_io_qpairs,
  			   per_process_tailq, tmp_qpair) {
  		if (active_qpair == qpair) {
  			TAILQ_REMOVE(&active_proc->allocated_io_qpairs,
  				     active_qpair, per_process_tailq);
  
  			break;
  		}
  	}
  }
  
  void
  spdk_nvme_ctrlr_get_default_io_qpair_opts(struct spdk_nvme_ctrlr *ctrlr,
  		struct spdk_nvme_io_qpair_opts *opts,
  		size_t opts_size)
  {
  	assert(ctrlr);
  
  	assert(opts);
  
  	memset(opts, 0, opts_size);
  
  #define FIELD_OK(field) \
  	offsetof(struct spdk_nvme_io_qpair_opts, field) + sizeof(opts->field) <= opts_size
  
  	if (FIELD_OK(qprio)) {
  		opts->qprio = SPDK_NVME_QPRIO_URGENT;
  	}
  
  	if (FIELD_OK(io_queue_size)) {
  		opts->io_queue_size = ctrlr->opts.io_queue_size;
  	}
  
  	if (FIELD_OK(io_queue_requests)) {
  		opts->io_queue_requests = ctrlr->opts.io_queue_requests;
  	}
  
  	if (FIELD_OK(delay_cmd_submit)) {
  		opts->delay_cmd_submit = false;
  	}
  
  	if (FIELD_OK(sq.vaddr)) {
  		opts->sq.vaddr = NULL;
  	}
  
  	if (FIELD_OK(sq.paddr)) {
  		opts->sq.paddr = 0;
  	}
  
  	if (FIELD_OK(sq.buffer_size)) {
  		opts->sq.buffer_size = 0;
  	}
  
  	if (FIELD_OK(cq.vaddr)) {
  		opts->cq.vaddr = NULL;
  	}
  
  	if (FIELD_OK(cq.paddr)) {
  		opts->cq.paddr = 0;
  	}
  
  	if (FIELD_OK(cq.buffer_size)) {
  		opts->cq.buffer_size = 0;
  	}
  
  	if (FIELD_OK(create_only)) {
  		opts->create_only = false;
  	}
  
  #undef FIELD_OK
  }
  
  static struct spdk_nvme_qpair *
  nvme_ctrlr_create_io_qpair(struct spdk_nvme_ctrlr *ctrlr,
  			   const struct spdk_nvme_io_qpair_opts *opts)
  {
  	uint32_t				qid;
  	struct spdk_nvme_qpair			*qpair;
  	union spdk_nvme_cc_register		cc;
  
  	if (!ctrlr) {
  		return NULL;
  	}
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	if (nvme_ctrlr_get_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("get_cc failed\n");
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return NULL;
  	}
  
  	if (opts->qprio & ~SPDK_NVME_CREATE_IO_SQ_QPRIO_MASK) {
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return NULL;
  	}
  
  	/*
  	 * Only value SPDK_NVME_QPRIO_URGENT(0) is valid for the
  	 * default round robin arbitration method.
  	 */
  	if ((cc.bits.ams == SPDK_NVME_CC_AMS_RR) && (opts->qprio != SPDK_NVME_QPRIO_URGENT)) {
  		SPDK_ERRLOG("invalid queue priority for default round robin arbitration method\n");
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return NULL;
  	}
  
  	/*
  	 * Get the first available I/O queue ID.
  	 */
  	qid = spdk_bit_array_find_first_set(ctrlr->free_io_qids, 1);
  	if (qid > ctrlr->opts.num_io_queues) {
  		SPDK_ERRLOG("No free I/O queue IDs\n");
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return NULL;
  	}
  
  	qpair = nvme_transport_ctrlr_create_io_qpair(ctrlr, qid, opts);
  	if (qpair == NULL) {
  		SPDK_ERRLOG("nvme_transport_ctrlr_create_io_qpair() failed\n");
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return NULL;
  	}
  
  	spdk_bit_array_clear(ctrlr->free_io_qids, qid);
  	TAILQ_INSERT_TAIL(&ctrlr->active_io_qpairs, qpair, tailq);
  
  	nvme_ctrlr_proc_add_io_qpair(qpair);
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	return qpair;
  }
  
  int
  spdk_nvme_ctrlr_connect_io_qpair(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_qpair *qpair)
  {
  	int rc;
  
  	if (nvme_qpair_get_state(qpair) != NVME_QPAIR_DISABLED) {
  		return -EISCONN;
  	}
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	rc = nvme_transport_ctrlr_connect_qpair(ctrlr, qpair);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	if (ctrlr->quirks & NVME_QUIRK_DELAY_AFTER_QUEUE_ALLOC) {
  		spdk_delay_us(100);
  	}
  
  	return rc;
  }
  
  void
  spdk_nvme_ctrlr_disconnect_io_qpair(struct spdk_nvme_qpair *qpair)
  {
  	struct spdk_nvme_ctrlr *ctrlr = qpair->ctrlr;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	nvme_transport_ctrlr_disconnect_qpair(ctrlr, qpair);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  struct spdk_nvme_qpair *
  spdk_nvme_ctrlr_alloc_io_qpair(struct spdk_nvme_ctrlr *ctrlr,
  			       const struct spdk_nvme_io_qpair_opts *user_opts,
  			       size_t opts_size)
  {
  
  	struct spdk_nvme_qpair		*qpair;
  	struct spdk_nvme_io_qpair_opts	opts;
  	int				rc;
  
  	/*
  	 * Get the default options, then overwrite them with the user-provided options
  	 * up to opts_size.
  	 *
  	 * This allows for extensions of the opts structure without breaking
  	 * ABI compatibility.
  	 */
  	spdk_nvme_ctrlr_get_default_io_qpair_opts(ctrlr, &opts, sizeof(opts));
  	if (user_opts) {
  		memcpy(&opts, user_opts, spdk_min(sizeof(opts), opts_size));
  
  		/* If user passes buffers, make sure they're big enough for the requested queue size */
  		if (opts.sq.vaddr) {
  			if (opts.sq.buffer_size < (opts.io_queue_size * sizeof(struct spdk_nvme_cmd))) {
  				SPDK_ERRLOG("sq buffer size %lx is too small for sq size %lx\n",
  					    opts.sq.buffer_size, (opts.io_queue_size * sizeof(struct spdk_nvme_cmd)));
  				return NULL;
  			}
  		}
  		if (opts.cq.vaddr) {
  			if (opts.cq.buffer_size < (opts.io_queue_size * sizeof(struct spdk_nvme_cpl))) {
  				SPDK_ERRLOG("cq buffer size %lx is too small for cq size %lx\n",
  					    opts.cq.buffer_size, (opts.io_queue_size * sizeof(struct spdk_nvme_cpl)));
  				return NULL;
  			}
  		}
  	}
  
  	qpair = nvme_ctrlr_create_io_qpair(ctrlr, &opts);
  
  	if (qpair == NULL || opts.create_only == true) {
  		return qpair;
  	}
  
  	rc = spdk_nvme_ctrlr_connect_io_qpair(ctrlr, qpair);
  	if (rc != 0) {
  		SPDK_ERRLOG("nvme_transport_ctrlr_connect_io_qpair() failed\n");
  		nvme_transport_ctrlr_delete_io_qpair(ctrlr, qpair);
  		return NULL;
  	}
  
  	return qpair;
  }
  
  int
  spdk_nvme_ctrlr_reconnect_io_qpair(struct spdk_nvme_qpair *qpair)
  {
  	struct spdk_nvme_ctrlr *ctrlr;
  	int rc;
  
  	assert(qpair != NULL);
  	assert(nvme_qpair_is_admin_queue(qpair) == false);
  	assert(qpair->ctrlr != NULL);
  
  	ctrlr = qpair->ctrlr;
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	if (ctrlr->is_removed) {
  		rc = -ENODEV;
  		goto out;
  	}
  
  	if (ctrlr->is_resetting) {
  		rc = -EAGAIN;
  		goto out;
  	}
  
  	if (ctrlr->is_failed) {
  		rc = -ENXIO;
  		goto out;
  	}
  
  	if (nvme_qpair_get_state(qpair) != NVME_QPAIR_DISABLED) {
  		rc = 0;
  		goto out;
  	}
  
  	/* We have to confirm that any old memory is cleaned up. */
  	nvme_transport_ctrlr_disconnect_qpair(ctrlr, qpair);
  
  	rc = nvme_transport_ctrlr_connect_qpair(ctrlr, qpair);
  	if (rc) {
  		rc = -EAGAIN;
  		goto out;
  	}
  
  out:
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  	return rc;
  }
  
  spdk_nvme_qp_failure_reason
  spdk_nvme_ctrlr_get_admin_qp_failure_reason(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->adminq->transport_failure_reason;
  }
  
  /*
   * This internal function will attempt to take the controller
   * lock before calling disconnect on a controller qpair.
   * Functions already holding the controller lock should
   * call nvme_transport_ctrlr_disconnect_qpair directly.
   */
  void
  nvme_ctrlr_disconnect_qpair(struct spdk_nvme_qpair *qpair)
  {
  	struct spdk_nvme_ctrlr *ctrlr = qpair->ctrlr;
  
  	assert(ctrlr != NULL);
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	nvme_transport_ctrlr_disconnect_qpair(ctrlr, qpair);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  int
  spdk_nvme_ctrlr_free_io_qpair(struct spdk_nvme_qpair *qpair)
  {
  	struct spdk_nvme_ctrlr *ctrlr;
  
  	if (qpair == NULL) {
  		return 0;
  	}
  
  	ctrlr = qpair->ctrlr;
  
  	if (qpair->in_completion_context) {
  		/*
  		 * There are many cases where it is convenient to delete an io qpair in the context
  		 *  of that qpair's completion routine.  To handle this properly, set a flag here
  		 *  so that the completion routine will perform an actual delete after the context
  		 *  unwinds.
  		 */
  		qpair->delete_after_completion_context = 1;
  		return 0;
  	}
  
  	if (qpair->poll_group) {
  		spdk_nvme_poll_group_remove(qpair->poll_group->group, qpair);
  	}
  
  	/* Do not retry. */
  	nvme_qpair_abort_reqs(qpair, 1);
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	nvme_ctrlr_proc_remove_io_qpair(qpair);
  
  	TAILQ_REMOVE(&ctrlr->active_io_qpairs, qpair, tailq);
  	spdk_bit_array_set(ctrlr->free_io_qids, qpair->id);
  
  	if (nvme_transport_ctrlr_delete_io_qpair(ctrlr, qpair)) {
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return -1;
  	}
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  	return 0;
  }
  
  static void
  nvme_ctrlr_construct_intel_support_log_page_list(struct spdk_nvme_ctrlr *ctrlr,
  		struct spdk_nvme_intel_log_page_directory *log_page_directory)
  {
  	if (log_page_directory == NULL) {
  		return;
  	}
  
  	if (ctrlr->cdata.vid != SPDK_PCI_VID_INTEL) {
  		return;
  	}
  
  	ctrlr->log_page_supported[SPDK_NVME_INTEL_LOG_PAGE_DIRECTORY] = true;
  
  	if (log_page_directory->read_latency_log_len ||
  	    (ctrlr->quirks & NVME_INTEL_QUIRK_READ_LATENCY)) {
  		ctrlr->log_page_supported[SPDK_NVME_INTEL_LOG_READ_CMD_LATENCY] = true;
  	}
  	if (log_page_directory->write_latency_log_len ||
  	    (ctrlr->quirks & NVME_INTEL_QUIRK_WRITE_LATENCY)) {
  		ctrlr->log_page_supported[SPDK_NVME_INTEL_LOG_WRITE_CMD_LATENCY] = true;
  	}
  	if (log_page_directory->temperature_statistics_log_len) {
  		ctrlr->log_page_supported[SPDK_NVME_INTEL_LOG_TEMPERATURE] = true;
  	}
  	if (log_page_directory->smart_log_len) {
  		ctrlr->log_page_supported[SPDK_NVME_INTEL_LOG_SMART] = true;
  	}
  	if (log_page_directory->marketing_description_log_len) {
  		ctrlr->log_page_supported[SPDK_NVME_INTEL_MARKETING_DESCRIPTION] = true;
  	}
  }
  
  static int nvme_ctrlr_set_intel_support_log_pages(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc = 0;
  	struct nvme_completion_poll_status	*status;
  	struct spdk_nvme_intel_log_page_directory *log_page_directory;
  
  	log_page_directory = spdk_zmalloc(sizeof(struct spdk_nvme_intel_log_page_directory),
  					  64, NULL, SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_DMA);
  	if (log_page_directory == NULL) {
  		SPDK_ERRLOG("could not allocate log_page_directory\n");
  		return -ENXIO;
  	}
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		spdk_free(log_page_directory);
  		return -ENOMEM;
  	}
  
  	rc = spdk_nvme_ctrlr_cmd_get_log_page(ctrlr, SPDK_NVME_INTEL_LOG_PAGE_DIRECTORY,
  					      SPDK_NVME_GLOBAL_NS_TAG, log_page_directory,
  					      sizeof(struct spdk_nvme_intel_log_page_directory),
  					      0, nvme_completion_poll_cb, status);
  	if (rc != 0) {
  		spdk_free(log_page_directory);
  		free(status);
  		return rc;
  	}
  
  	if (spdk_nvme_wait_for_completion_timeout(ctrlr->adminq, status,
  			ctrlr->opts.admin_timeout_ms / 1000)) {
  		spdk_free(log_page_directory);
  		SPDK_WARNLOG("Intel log pages not supported on Intel drive!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return 0;
  	}
  
  	nvme_ctrlr_construct_intel_support_log_page_list(ctrlr, log_page_directory);
  	spdk_free(log_page_directory);
  	free(status);
  	return 0;
  }
  
  static int
  nvme_ctrlr_set_supported_log_pages(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int	rc = 0;
  
  	memset(ctrlr->log_page_supported, 0, sizeof(ctrlr->log_page_supported));
  	/* Mandatory pages */
  	ctrlr->log_page_supported[SPDK_NVME_LOG_ERROR] = true;
  	ctrlr->log_page_supported[SPDK_NVME_LOG_HEALTH_INFORMATION] = true;
  	ctrlr->log_page_supported[SPDK_NVME_LOG_FIRMWARE_SLOT] = true;
  	if (ctrlr->cdata.lpa.celp) {
  		ctrlr->log_page_supported[SPDK_NVME_LOG_COMMAND_EFFECTS_LOG] = true;
  	}
  	if (ctrlr->cdata.vid == SPDK_PCI_VID_INTEL && !(ctrlr->quirks & NVME_INTEL_QUIRK_NO_LOG_PAGES)) {
  		rc = nvme_ctrlr_set_intel_support_log_pages(ctrlr);
  	}
  
  	return rc;
  }
  
  static void
  nvme_ctrlr_set_intel_supported_features(struct spdk_nvme_ctrlr *ctrlr)
  {
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_MAX_LBA] = true;
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_NATIVE_MAX_LBA] = true;
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_POWER_GOVERNOR_SETTING] = true;
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_SMBUS_ADDRESS] = true;
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_LED_PATTERN] = true;
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_RESET_TIMED_WORKLOAD_COUNTERS] = true;
  	ctrlr->feature_supported[SPDK_NVME_INTEL_FEAT_LATENCY_TRACKING] = true;
  }
  
  static void
  nvme_ctrlr_set_arbitration_feature(struct spdk_nvme_ctrlr *ctrlr)
  {
  	uint32_t cdw11;
  	struct nvme_completion_poll_status *status;
  
  	if (ctrlr->opts.arbitration_burst == 0) {
  		return;
  	}
  
  	if (ctrlr->opts.arbitration_burst > 7) {
  		SPDK_WARNLOG("Valid arbitration burst values is from 0-7\n");
  		return;
  	}
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return;
  	}
  
  	cdw11 = ctrlr->opts.arbitration_burst;
  
  	if (spdk_nvme_ctrlr_get_flags(ctrlr) & SPDK_NVME_CTRLR_WRR_SUPPORTED) {
  		cdw11 |= (uint32_t)ctrlr->opts.low_priority_weight << 8;
  		cdw11 |= (uint32_t)ctrlr->opts.medium_priority_weight << 16;
  		cdw11 |= (uint32_t)ctrlr->opts.high_priority_weight << 24;
  	}
  
  	if (spdk_nvme_ctrlr_cmd_set_feature(ctrlr, SPDK_NVME_FEAT_ARBITRATION,
  					    cdw11, 0, NULL, 0,
  					    nvme_completion_poll_cb, status) < 0) {
  		SPDK_ERRLOG("Set arbitration feature failed\n");
  		free(status);
  		return;
  	}
  
  	if (spdk_nvme_wait_for_completion_timeout(ctrlr->adminq, status,
  			ctrlr->opts.admin_timeout_ms / 1000)) {
  		SPDK_ERRLOG("Timeout to set arbitration feature\n");
  	}
  
  	if (!status->timed_out) {
  		free(status);
  	}
  }
  
  static void
  nvme_ctrlr_set_supported_features(struct spdk_nvme_ctrlr *ctrlr)
  {
  	memset(ctrlr->feature_supported, 0, sizeof(ctrlr->feature_supported));
  	/* Mandatory features */
  	ctrlr->feature_supported[SPDK_NVME_FEAT_ARBITRATION] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_POWER_MANAGEMENT] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_TEMPERATURE_THRESHOLD] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_ERROR_RECOVERY] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_NUMBER_OF_QUEUES] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_INTERRUPT_COALESCING] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_INTERRUPT_VECTOR_CONFIGURATION] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_WRITE_ATOMICITY] = true;
  	ctrlr->feature_supported[SPDK_NVME_FEAT_ASYNC_EVENT_CONFIGURATION] = true;
  	/* Optional features */
  	if (ctrlr->cdata.vwc.present) {
  		ctrlr->feature_supported[SPDK_NVME_FEAT_VOLATILE_WRITE_CACHE] = true;
  	}
  	if (ctrlr->cdata.apsta.supported) {
  		ctrlr->feature_supported[SPDK_NVME_FEAT_AUTONOMOUS_POWER_STATE_TRANSITION] = true;
  	}
  	if (ctrlr->cdata.hmpre) {
  		ctrlr->feature_supported[SPDK_NVME_FEAT_HOST_MEM_BUFFER] = true;
  	}
  	if (ctrlr->cdata.vid == SPDK_PCI_VID_INTEL) {
  		nvme_ctrlr_set_intel_supported_features(ctrlr);
  	}
  
  	nvme_ctrlr_set_arbitration_feature(ctrlr);
  }
  
  bool
  spdk_nvme_ctrlr_is_failed(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->is_failed;
  }
  
  void
  nvme_ctrlr_fail(struct spdk_nvme_ctrlr *ctrlr, bool hot_remove)
  {
  	/*
  	 * Set the flag here and leave the work failure of qpairs to
  	 * spdk_nvme_qpair_process_completions().
  	 */
  	if (hot_remove) {
  		ctrlr->is_removed = true;
  	}
  	ctrlr->is_failed = true;
  	SPDK_ERRLOG("ctrlr %s in failed state.\n", ctrlr->trid.traddr);
  }
  
  /**
   * This public API function will try to take the controller lock.
   * Any private functions being called from a thread already holding
   * the ctrlr lock should call nvme_ctrlr_fail directly.
   */
  void
  spdk_nvme_ctrlr_fail(struct spdk_nvme_ctrlr *ctrlr)
  {
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	nvme_ctrlr_fail(ctrlr, false);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  static void
  nvme_ctrlr_shutdown(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_cc_register	cc;
  	union spdk_nvme_csts_register	csts;
  	uint32_t			ms_waited = 0;
  	uint32_t			shutdown_timeout_ms;
  
  	if (ctrlr->is_removed) {
  		return;
  	}
  
  	if (nvme_ctrlr_get_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("get_cc() failed\n");
  		return;
  	}
  
  	cc.bits.shn = SPDK_NVME_SHN_NORMAL;
  
  	if (nvme_ctrlr_set_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("set_cc() failed\n");
  		return;
  	}
  
  	/*
  	 * The NVMe specification defines RTD3E to be the time between
  	 *  setting SHN = 1 until the controller will set SHST = 10b.
  	 * If the device doesn't report RTD3 entry latency, or if it
  	 *  reports RTD3 entry latency less than 10 seconds, pick
  	 *  10 seconds as a reasonable amount of time to
  	 *  wait before proceeding.
  	 */
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "RTD3E = %" PRIu32 " us\n", ctrlr->cdata.rtd3e);
  	shutdown_timeout_ms = (ctrlr->cdata.rtd3e + 999) / 1000;
  	shutdown_timeout_ms = spdk_max(shutdown_timeout_ms, 10000);
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "shutdown timeout = %" PRIu32 " ms\n", shutdown_timeout_ms);
  
  	do {
  		if (nvme_ctrlr_get_csts(ctrlr, &csts)) {
  			SPDK_ERRLOG("get_csts() failed\n");
  			return;
  		}
  
  		if (csts.bits.shst == SPDK_NVME_SHST_COMPLETE) {
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "shutdown complete in %u milliseconds\n",
  				      ms_waited);
  			return;
  		}
  
  		nvme_delay(1000);
  		ms_waited++;
  	} while (ms_waited < shutdown_timeout_ms);
  
  	SPDK_ERRLOG("did not shutdown within %u milliseconds\n", shutdown_timeout_ms);
  	if (ctrlr->quirks & NVME_QUIRK_SHST_COMPLETE) {
  		SPDK_ERRLOG("likely due to shutdown handling in the VMWare emulated NVMe SSD\n");
  	}
  }
  
  static int
  nvme_ctrlr_enable(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_cc_register	cc;
  	int				rc;
  
  	rc = nvme_transport_ctrlr_enable(ctrlr);
  	if (rc != 0) {
  		SPDK_ERRLOG("transport ctrlr_enable failed\n");
  		return rc;
  	}
  
  	if (nvme_ctrlr_get_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("get_cc() failed\n");
  		return -EIO;
  	}
  
  	if (cc.bits.en != 0) {
  		SPDK_ERRLOG("called with CC.EN = 1\n");
  		return -EINVAL;
  	}
  
  	cc.bits.en = 1;
  	cc.bits.css = 0;
  	cc.bits.shn = 0;
  	cc.bits.iosqes = 6; /* SQ entry size == 64 == 2^6 */
  	cc.bits.iocqes = 4; /* CQ entry size == 16 == 2^4 */
  
  	/* Page size is 2 ^ (12 + mps). */
  	cc.bits.mps = spdk_u32log2(ctrlr->page_size) - 12;
  
  	if (ctrlr->cap.bits.css == 0) {
  		SPDK_INFOLOG(SPDK_LOG_NVME,
  			     "Drive reports no command sets supported. Assuming NVM is supported.\n");
  		ctrlr->cap.bits.css = SPDK_NVME_CAP_CSS_NVM;
  	}
  
  	if (!(ctrlr->cap.bits.css & (1u << ctrlr->opts.command_set))) {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Requested I/O command set %u but supported mask is 0x%x\n",
  			      ctrlr->opts.command_set, ctrlr->cap.bits.css);
  		return -EINVAL;
  	}
  
  	cc.bits.css = ctrlr->opts.command_set;
  
  	switch (ctrlr->opts.arb_mechanism) {
  	case SPDK_NVME_CC_AMS_RR:
  		break;
  	case SPDK_NVME_CC_AMS_WRR:
  		if (SPDK_NVME_CAP_AMS_WRR & ctrlr->cap.bits.ams) {
  			break;
  		}
  		return -EINVAL;
  	case SPDK_NVME_CC_AMS_VS:
  		if (SPDK_NVME_CAP_AMS_VS & ctrlr->cap.bits.ams) {
  			break;
  		}
  		return -EINVAL;
  	default:
  		return -EINVAL;
  	}
  
  	cc.bits.ams = ctrlr->opts.arb_mechanism;
  
  	if (nvme_ctrlr_set_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("set_cc() failed\n");
  		return -EIO;
  	}
  
  	return 0;
  }
  
  static int
  nvme_ctrlr_disable(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_cc_register	cc;
  
  	if (nvme_ctrlr_get_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("get_cc() failed\n");
  		return -EIO;
  	}
  
  	if (cc.bits.en == 0) {
  		return 0;
  	}
  
  	cc.bits.en = 0;
  
  	if (nvme_ctrlr_set_cc(ctrlr, &cc)) {
  		SPDK_ERRLOG("set_cc() failed\n");
  		return -EIO;
  	}
  
  	return 0;
  }
  
  #ifdef DEBUG
  static const char *
  nvme_ctrlr_state_string(enum nvme_ctrlr_state state)
  {
  	switch (state) {
  	case NVME_CTRLR_STATE_INIT_DELAY:
  		return "delay init";
  	case NVME_CTRLR_STATE_INIT:
  		return "init";
  	case NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_1:
  		return "disable and wait for CSTS.RDY = 1";
  	case NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_0:
  		return "disable and wait for CSTS.RDY = 0";
  	case NVME_CTRLR_STATE_ENABLE:
  		return "enable controller by writing CC.EN = 1";
  	case NVME_CTRLR_STATE_ENABLE_WAIT_FOR_READY_1:
  		return "wait for CSTS.RDY = 1";
  	case NVME_CTRLR_STATE_RESET_ADMIN_QUEUE:
  		return "reset admin queue";
  	case NVME_CTRLR_STATE_IDENTIFY:
  		return "identify controller";
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY:
  		return "wait for identify controller";
  	case NVME_CTRLR_STATE_SET_NUM_QUEUES:
  		return "set number of queues";
  	case NVME_CTRLR_STATE_WAIT_FOR_SET_NUM_QUEUES:
  		return "wait for set number of queues";
  	case NVME_CTRLR_STATE_CONSTRUCT_NS:
  		return "construct namespaces";
  	case NVME_CTRLR_STATE_IDENTIFY_ACTIVE_NS:
  		return "identify active ns";
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_ACTIVE_NS:
  		return "wait for identify active ns";
  	case NVME_CTRLR_STATE_IDENTIFY_NS:
  		return "identify ns";
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_NS:
  		return "wait for identify ns";
  	case NVME_CTRLR_STATE_IDENTIFY_ID_DESCS:
  		return "identify namespace id descriptors";
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_ID_DESCS:
  		return "wait for identify namespace id descriptors";
  	case NVME_CTRLR_STATE_CONFIGURE_AER:
  		return "configure AER";
  	case NVME_CTRLR_STATE_WAIT_FOR_CONFIGURE_AER:
  		return "wait for configure aer";
  	case NVME_CTRLR_STATE_SET_SUPPORTED_LOG_PAGES:
  		return "set supported log pages";
  	case NVME_CTRLR_STATE_SET_SUPPORTED_FEATURES:
  		return "set supported features";
  	case NVME_CTRLR_STATE_SET_DB_BUF_CFG:
  		return "set doorbell buffer config";
  	case NVME_CTRLR_STATE_WAIT_FOR_DB_BUF_CFG:
  		return "wait for doorbell buffer config";
  	case NVME_CTRLR_STATE_SET_KEEP_ALIVE_TIMEOUT:
  		return "set keep alive timeout";
  	case NVME_CTRLR_STATE_WAIT_FOR_KEEP_ALIVE_TIMEOUT:
  		return "wait for set keep alive timeout";
  	case NVME_CTRLR_STATE_SET_HOST_ID:
  		return "set host ID";
  	case NVME_CTRLR_STATE_WAIT_FOR_HOST_ID:
  		return "wait for set host ID";
  	case NVME_CTRLR_STATE_READY:
  		return "ready";
  	case NVME_CTRLR_STATE_ERROR:
  		return "error";
  	}
  	return "unknown";
  };
  #endif /* DEBUG */
  
  static void
  nvme_ctrlr_set_state(struct spdk_nvme_ctrlr *ctrlr, enum nvme_ctrlr_state state,
  		     uint64_t timeout_in_ms)
  {
  	uint64_t ticks_per_ms, timeout_in_ticks, now_ticks;
  
  	ctrlr->state = state;
  	if (timeout_in_ms == NVME_TIMEOUT_INFINITE) {
  		goto inf;
  	}
  
  	ticks_per_ms = spdk_get_ticks_hz() / 1000;
  	if (timeout_in_ms > UINT64_MAX / ticks_per_ms) {
  		SPDK_ERRLOG("Specified timeout would cause integer overflow. Defaulting to no timeout.\n");
  		goto inf;
  	}
  
  	now_ticks = spdk_get_ticks();
  	timeout_in_ticks = timeout_in_ms * ticks_per_ms;
  	if (timeout_in_ticks > UINT64_MAX - now_ticks) {
  		SPDK_ERRLOG("Specified timeout would cause integer overflow. Defaulting to no timeout.\n");
  		goto inf;
  	}
  
  	ctrlr->state_timeout_tsc = timeout_in_ticks + now_ticks;
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "setting state to %s (timeout %" PRIu64 " ms)\n",
  		      nvme_ctrlr_state_string(ctrlr->state), ctrlr->state_timeout_tsc);
  	return;
  inf:
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "setting state to %s (no timeout)\n",
  		      nvme_ctrlr_state_string(ctrlr->state));
  	ctrlr->state_timeout_tsc = NVME_TIMEOUT_INFINITE;
  }
  
  static void
  nvme_ctrlr_free_doorbell_buffer(struct spdk_nvme_ctrlr *ctrlr)
  {
  	if (ctrlr->shadow_doorbell) {
  		spdk_free(ctrlr->shadow_doorbell);
  		ctrlr->shadow_doorbell = NULL;
  	}
  
  	if (ctrlr->eventidx) {
  		spdk_free(ctrlr->eventidx);
  		ctrlr->eventidx = NULL;
  	}
  }
  
  static void
  nvme_ctrlr_set_doorbell_buffer_config_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct spdk_nvme_ctrlr *ctrlr = (struct spdk_nvme_ctrlr *)arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		SPDK_WARNLOG("Doorbell buffer config failed\n");
  	} else {
  		SPDK_INFOLOG(SPDK_LOG_NVME, "NVMe controller: %s doorbell buffer config enabled\n",
  			     ctrlr->trid.traddr);
  	}
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_KEEP_ALIVE_TIMEOUT,
  			     ctrlr->opts.admin_timeout_ms);
  }
  
  static int
  nvme_ctrlr_set_doorbell_buffer_config(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc = 0;
  	uint64_t prp1, prp2, len;
  
  	if (!ctrlr->cdata.oacs.doorbell_buffer_config) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_KEEP_ALIVE_TIMEOUT,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	if (ctrlr->trid.trtype != SPDK_NVME_TRANSPORT_PCIE) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_KEEP_ALIVE_TIMEOUT,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	/* only 1 page size for doorbell buffer */
  	ctrlr->shadow_doorbell = spdk_zmalloc(ctrlr->page_size, ctrlr->page_size,
  					      NULL, SPDK_ENV_LCORE_ID_ANY,
  					      SPDK_MALLOC_DMA | SPDK_MALLOC_SHARE);
  	if (ctrlr->shadow_doorbell == NULL) {
  		rc = -ENOMEM;
  		goto error;
  	}
  
  	len = ctrlr->page_size;
  	prp1 = spdk_vtophys(ctrlr->shadow_doorbell, &len);
  	if (prp1 == SPDK_VTOPHYS_ERROR || len != ctrlr->page_size) {
  		rc = -EFAULT;
  		goto error;
  	}
  
  	ctrlr->eventidx = spdk_zmalloc(ctrlr->page_size, ctrlr->page_size,
  				       NULL, SPDK_ENV_LCORE_ID_ANY,
  				       SPDK_MALLOC_DMA | SPDK_MALLOC_SHARE);
  	if (ctrlr->eventidx == NULL) {
  		rc = -ENOMEM;
  		goto error;
  	}
  
  	len = ctrlr->page_size;
  	prp2 = spdk_vtophys(ctrlr->eventidx, &len);
  	if (prp2 == SPDK_VTOPHYS_ERROR || len != ctrlr->page_size) {
  		rc = -EFAULT;
  		goto error;
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_DB_BUF_CFG,
  			     ctrlr->opts.admin_timeout_ms);
  
  	rc = nvme_ctrlr_cmd_doorbell_buffer_config(ctrlr, prp1, prp2,
  			nvme_ctrlr_set_doorbell_buffer_config_done, ctrlr);
  	if (rc != 0) {
  		goto error;
  	}
  
  	return 0;
  
  error:
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  	nvme_ctrlr_free_doorbell_buffer(ctrlr);
  	return rc;
  }
  
  int
  spdk_nvme_ctrlr_reset(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc = 0;
  	struct spdk_nvme_qpair	*qpair;
  	struct nvme_request	*req, *tmp;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	if (ctrlr->is_resetting || ctrlr->is_removed) {
  		/*
  		 * Controller is already resetting or has been removed. Return
  		 *  immediately since there is no need to kick off another
  		 *  reset in these cases.
  		 */
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return ctrlr->is_resetting ? 0 : -ENXIO;
  	}
  
  	ctrlr->is_resetting = true;
  	ctrlr->is_failed = false;
  
  	SPDK_NOTICELOG("resetting controller\n");
  
  	/* Free all of the queued abort requests */
  	STAILQ_FOREACH_SAFE(req, &ctrlr->queued_aborts, stailq, tmp) {
  		STAILQ_REMOVE_HEAD(&ctrlr->queued_aborts, stailq);
  		nvme_free_request(req);
  		ctrlr->outstanding_aborts--;
  	}
  
  	nvme_transport_admin_qpair_abort_aers(ctrlr->adminq);
  
  	/* Disable all queues before disabling the controller hardware. */
  	TAILQ_FOREACH(qpair, &ctrlr->active_io_qpairs, tailq) {
  		qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
  		nvme_qpair_set_state(qpair, NVME_QPAIR_DISABLED);
  	}
  	nvme_qpair_set_state(ctrlr->adminq, NVME_QPAIR_DISABLED);
  	nvme_qpair_complete_error_reqs(ctrlr->adminq);
  	nvme_transport_qpair_abort_reqs(ctrlr->adminq, 0 /* retry */);
  	ctrlr->adminq->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
  	nvme_transport_ctrlr_disconnect_qpair(ctrlr, ctrlr->adminq);
  	if (nvme_transport_ctrlr_connect_qpair(ctrlr, ctrlr->adminq) != 0) {
  		SPDK_ERRLOG("Controller reinitialization failed.\n");
  		rc = -1;
  		goto out;
  	}
  
  	/* Doorbell buffer config is invalid during reset */
  	nvme_ctrlr_free_doorbell_buffer(ctrlr);
  
  	/* Set the state back to INIT to cause a full hardware reset. */
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_INIT, NVME_TIMEOUT_INFINITE);
  
  	nvme_qpair_set_state(ctrlr->adminq, NVME_QPAIR_ENABLED);
  	while (ctrlr->state != NVME_CTRLR_STATE_READY) {
  		if (nvme_ctrlr_process_init(ctrlr) != 0) {
  			SPDK_ERRLOG("controller reinitialization failed\n");
  			rc = -1;
  			break;
  		}
  	}
  
  	/*
  	 * For PCIe controllers, the memory locations of the tranpsort qpair
  	 * don't change when the controller is reset. They simply need to be
  	 * re-enabled with admin commands to the controller. For fabric
  	 * controllers we need to disconnect and reconnect the qpair on its
  	 * own thread outside of the context of the reset.
  	 */
  	if (rc == 0 && ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_PCIE) {
  		/* Reinitialize qpairs */
  		TAILQ_FOREACH(qpair, &ctrlr->active_io_qpairs, tailq) {
  			if (nvme_transport_ctrlr_connect_qpair(ctrlr, qpair) != 0) {
  				qpair->transport_failure_reason = SPDK_NVME_QPAIR_FAILURE_LOCAL;
  				rc = -1;
  				continue;
  			}
  		}
  	}
  
  out:
  	if (rc) {
  		nvme_ctrlr_fail(ctrlr, false);
  	}
  	ctrlr->is_resetting = false;
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	return rc;
  }
  
  int
  spdk_nvme_ctrlr_set_trid(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_transport_id *trid)
  {
  	int rc = 0;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	if (ctrlr->is_failed == false) {
  		rc = -EPERM;
  		goto out;
  	}
  
  	if (trid->trtype != ctrlr->trid.trtype) {
  		rc = -EINVAL;
  		goto out;
  	}
  
  	if (strncmp(trid->subnqn, ctrlr->trid.subnqn, SPDK_NVMF_NQN_MAX_LEN)) {
  		rc = -EINVAL;
  		goto out;
  	}
  
  	ctrlr->trid = *trid;
  
  out:
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  	return rc;
  }
  
  static void
  nvme_ctrlr_identify_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct spdk_nvme_ctrlr *ctrlr = (struct spdk_nvme_ctrlr *)arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		SPDK_ERRLOG("nvme_identify_controller failed!\n");
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return;
  	}
  
  	/*
  	 * Use MDTS to ensure our default max_xfer_size doesn't exceed what the
  	 *  controller supports.
  	 */
  	ctrlr->max_xfer_size = nvme_transport_ctrlr_get_max_xfer_size(ctrlr);
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "transport max_xfer_size %u\n", ctrlr->max_xfer_size);
  	if (ctrlr->cdata.mdts > 0) {
  		ctrlr->max_xfer_size = spdk_min(ctrlr->max_xfer_size,
  						ctrlr->min_page_size * (1 << (ctrlr->cdata.mdts)));
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "MDTS max_xfer_size %u\n", ctrlr->max_xfer_size);
  	}
  
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "CNTLID 0x%04" PRIx16 "\n", ctrlr->cdata.cntlid);
  	if (ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_PCIE) {
  		ctrlr->cntlid = ctrlr->cdata.cntlid;
  	} else {
  		/*
  		 * Fabrics controllers should already have CNTLID from the Connect command.
  		 *
  		 * If CNTLID from Connect doesn't match CNTLID in the Identify Controller data,
  		 * trust the one from Connect.
  		 */
  		if (ctrlr->cntlid != ctrlr->cdata.cntlid) {
  			SPDK_DEBUGLOG(SPDK_LOG_NVME,
  				      "Identify CNTLID 0x%04" PRIx16 " != Connect CNTLID 0x%04" PRIx16 "\n",
  				      ctrlr->cdata.cntlid, ctrlr->cntlid);
  		}
  	}
  
  	if (ctrlr->cdata.sgls.supported) {
  		assert(ctrlr->cdata.sgls.supported != 0x3);
  		ctrlr->flags |= SPDK_NVME_CTRLR_SGL_SUPPORTED;
  		if (ctrlr->cdata.sgls.supported == 0x2) {
  			ctrlr->flags |= SPDK_NVME_CTRLR_SGL_REQUIRES_DWORD_ALIGNMENT;
  		}
  		/*
  		 * Use MSDBD to ensure our max_sges doesn't exceed what the
  		 *  controller supports.
  		 */
  		ctrlr->max_sges = nvme_transport_ctrlr_get_max_sges(ctrlr);
  		if (ctrlr->cdata.nvmf_specific.msdbd != 0) {
  			ctrlr->max_sges = spdk_min(ctrlr->cdata.nvmf_specific.msdbd, ctrlr->max_sges);
  		} else {
  			/* A value 0 indicates no limit. */
  		}
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "transport max_sges %u\n", ctrlr->max_sges);
  	}
  
  	if (ctrlr->cdata.oacs.security) {
  		ctrlr->flags |= SPDK_NVME_CTRLR_SECURITY_SEND_RECV_SUPPORTED;
  	}
  
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "fuses compare and write: %d\n", ctrlr->cdata.fuses.compare_and_write);
  	if (ctrlr->cdata.fuses.compare_and_write) {
  		ctrlr->flags |= SPDK_NVME_CTRLR_COMPARE_AND_WRITE_SUPPORTED;
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_NUM_QUEUES,
  			     ctrlr->opts.admin_timeout_ms);
  }
  
  static int
  nvme_ctrlr_identify(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int	rc;
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY,
  			     ctrlr->opts.admin_timeout_ms);
  
  	rc = nvme_ctrlr_cmd_identify(ctrlr, SPDK_NVME_IDENTIFY_CTRLR, 0, 0,
  				     &ctrlr->cdata, sizeof(ctrlr->cdata),
  				     nvme_ctrlr_identify_done, ctrlr);
  	if (rc != 0) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return rc;
  	}
  
  	return 0;
  }
  
  enum nvme_active_ns_state {
  	NVME_ACTIVE_NS_STATE_IDLE,
  	NVME_ACTIVE_NS_STATE_PROCESSING,
  	NVME_ACTIVE_NS_STATE_DONE,
  	NVME_ACTIVE_NS_STATE_ERROR
  };
  
  typedef void (*nvme_active_ns_ctx_deleter)(struct nvme_active_ns_ctx *);
  
  struct nvme_active_ns_ctx {
  	struct spdk_nvme_ctrlr *ctrlr;
  	uint32_t page;
  	uint32_t num_pages;
  	uint32_t next_nsid;
  	uint32_t *new_ns_list;
  	nvme_active_ns_ctx_deleter deleter;
  
  	enum nvme_active_ns_state state;
  };
  
  static struct nvme_active_ns_ctx *
  nvme_active_ns_ctx_create(struct spdk_nvme_ctrlr *ctrlr, nvme_active_ns_ctx_deleter deleter)
  {
  	struct nvme_active_ns_ctx *ctx;
  	uint32_t num_pages = 0;
  	uint32_t *new_ns_list = NULL;
  
  	ctx = calloc(1, sizeof(*ctx));
  	if (!ctx) {
  		SPDK_ERRLOG("Failed to allocate nvme_active_ns_ctx!\n");
  		return NULL;
  	}
  
  	if (ctrlr->num_ns) {
  		/* The allocated size must be a multiple of sizeof(struct spdk_nvme_ns_list) */
  		num_pages = (ctrlr->num_ns * sizeof(new_ns_list[0]) - 1) / sizeof(struct spdk_nvme_ns_list) + 1;
  		new_ns_list = spdk_zmalloc(num_pages * sizeof(struct spdk_nvme_ns_list), ctrlr->page_size,
  					   NULL, SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA | SPDK_MALLOC_SHARE);
  		if (!new_ns_list) {
  			SPDK_ERRLOG("Failed to allocate active_ns_list!\n");
  			free(ctx);
  			return NULL;
  		}
  	}
  
  	ctx->num_pages = num_pages;
  	ctx->new_ns_list = new_ns_list;
  	ctx->ctrlr = ctrlr;
  	ctx->deleter = deleter;
  
  	return ctx;
  }
  
  static void
  nvme_active_ns_ctx_destroy(struct nvme_active_ns_ctx *ctx)
  {
  	spdk_free(ctx->new_ns_list);
  	free(ctx);
  }
  
  static void
  nvme_ctrlr_identify_active_ns_swap(struct spdk_nvme_ctrlr *ctrlr, uint32_t **new_ns_list)
  {
  	spdk_free(ctrlr->active_ns_list);
  	ctrlr->active_ns_list = *new_ns_list;
  	*new_ns_list = NULL;
  }
  
  static void
  nvme_ctrlr_identify_active_ns_async_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct nvme_active_ns_ctx *ctx = arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		ctx->state = NVME_ACTIVE_NS_STATE_ERROR;
  		goto out;
  	}
  
  	ctx->next_nsid = ctx->new_ns_list[1024 * ctx->page + 1023];
  	if (ctx->next_nsid == 0 || ++ctx->page == ctx->num_pages) {
  		ctx->state = NVME_ACTIVE_NS_STATE_DONE;
  		goto out;
  	}
  
  	nvme_ctrlr_identify_active_ns_async(ctx);
  	return;
  
  out:
  	if (ctx->deleter) {
  		ctx->deleter(ctx);
  	}
  }
  
  static void
  nvme_ctrlr_identify_active_ns_async(struct nvme_active_ns_ctx *ctx)
  {
  	struct spdk_nvme_ctrlr *ctrlr = ctx->ctrlr;
  	uint32_t i;
  	int rc;
  
  	if (ctrlr->num_ns == 0) {
  		ctx->state = NVME_ACTIVE_NS_STATE_DONE;
  		goto out;
  	}
  
  	/*
  	 * If controller doesn't support active ns list CNS 0x02 dummy up
  	 * an active ns list, i.e. all namespaces report as active
  	 */
  	if (ctrlr->vs.raw < SPDK_NVME_VERSION(1, 1, 0) || ctrlr->quirks & NVME_QUIRK_IDENTIFY_CNS) {
  		for (i = 0; i < ctrlr->num_ns; i++) {
  			ctx->new_ns_list[i] = i + 1;
  		}
  
  		ctx->state = NVME_ACTIVE_NS_STATE_DONE;
  		goto out;
  	}
  
  	ctx->state = NVME_ACTIVE_NS_STATE_PROCESSING;
  	rc = nvme_ctrlr_cmd_identify(ctrlr, SPDK_NVME_IDENTIFY_ACTIVE_NS_LIST, 0, ctx->next_nsid,
  				     &ctx->new_ns_list[1024 * ctx->page], sizeof(struct spdk_nvme_ns_list),
  				     nvme_ctrlr_identify_active_ns_async_done, ctx);
  	if (rc != 0) {
  		ctx->state = NVME_ACTIVE_NS_STATE_ERROR;
  		goto out;
  	}
  
  	return;
  
  out:
  	if (ctx->deleter) {
  		ctx->deleter(ctx);
  	}
  }
  
  static void
  _nvme_active_ns_ctx_deleter(struct nvme_active_ns_ctx *ctx)
  {
  	struct spdk_nvme_ctrlr *ctrlr = ctx->ctrlr;
  
  	if (ctx->state == NVME_ACTIVE_NS_STATE_ERROR) {
  		nvme_ctrlr_destruct_namespaces(ctrlr);
  		nvme_active_ns_ctx_destroy(ctx);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return;
  	}
  
  	assert(ctx->state == NVME_ACTIVE_NS_STATE_DONE);
  	nvme_ctrlr_identify_active_ns_swap(ctrlr, &ctx->new_ns_list);
  	nvme_active_ns_ctx_destroy(ctx);
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_IDENTIFY_NS, ctrlr->opts.admin_timeout_ms);
  }
  
  static void
  _nvme_ctrlr_identify_active_ns(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct nvme_active_ns_ctx *ctx;
  
  	ctx = nvme_active_ns_ctx_create(ctrlr, _nvme_active_ns_ctx_deleter);
  	if (!ctx) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return;
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_ACTIVE_NS,
  			     ctrlr->opts.admin_timeout_ms);
  	nvme_ctrlr_identify_active_ns_async(ctx);
  }
  
  int
  nvme_ctrlr_identify_active_ns(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct nvme_active_ns_ctx *ctx;
  	int rc;
  
  	ctx = nvme_active_ns_ctx_create(ctrlr, NULL);
  	if (!ctx) {
  		return -ENOMEM;
  	}
  
  	nvme_ctrlr_identify_active_ns_async(ctx);
  	while (ctx->state == NVME_ACTIVE_NS_STATE_PROCESSING) {
  		rc = spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		if (rc < 0) {
  			ctx->state = NVME_ACTIVE_NS_STATE_ERROR;
  			break;
  		}
  	}
  
  	if (ctx->state == NVME_ACTIVE_NS_STATE_ERROR) {
  		nvme_active_ns_ctx_destroy(ctx);
  		return -ENXIO;
  	}
  
  	assert(ctx->state == NVME_ACTIVE_NS_STATE_DONE);
  	nvme_ctrlr_identify_active_ns_swap(ctrlr, &ctx->new_ns_list);
  	nvme_active_ns_ctx_destroy(ctx);
  
  	return 0;
  }
  
  static void
  nvme_ctrlr_identify_ns_async_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct spdk_nvme_ns *ns = (struct spdk_nvme_ns *)arg;
  	struct spdk_nvme_ctrlr *ctrlr = ns->ctrlr;
  	uint32_t nsid;
  	int rc;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return;
  	} else {
  		nvme_ns_set_identify_data(ns);
  	}
  
  	/* move on to the next active NS */
  	nsid = spdk_nvme_ctrlr_get_next_active_ns(ctrlr, ns->id);
  	ns = spdk_nvme_ctrlr_get_ns(ctrlr, nsid);
  	if (ns == NULL) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_IDENTIFY_ID_DESCS,
  				     ctrlr->opts.admin_timeout_ms);
  		return;
  	}
  	ns->ctrlr = ctrlr;
  	ns->id = nsid;
  
  	rc = nvme_ctrlr_identify_ns_async(ns);
  	if (rc) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  	}
  }
  
  static int
  nvme_ctrlr_identify_ns_async(struct spdk_nvme_ns *ns)
  {
  	struct spdk_nvme_ctrlr *ctrlr = ns->ctrlr;
  	struct spdk_nvme_ns_data *nsdata;
  
  	nsdata = &ctrlr->nsdata[ns->id - 1];
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_NS,
  			     ctrlr->opts.admin_timeout_ms);
  	return nvme_ctrlr_cmd_identify(ns->ctrlr, SPDK_NVME_IDENTIFY_NS, 0, ns->id,
  				       nsdata, sizeof(*nsdata),
  				       nvme_ctrlr_identify_ns_async_done, ns);
  }
  
  static int
  nvme_ctrlr_identify_namespaces(struct spdk_nvme_ctrlr *ctrlr)
  {
  	uint32_t nsid;
  	struct spdk_nvme_ns *ns;
  	int rc;
  
  	nsid = spdk_nvme_ctrlr_get_first_active_ns(ctrlr);
  	ns = spdk_nvme_ctrlr_get_ns(ctrlr, nsid);
  	if (ns == NULL) {
  		/* No active NS, move on to the next state */
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_CONFIGURE_AER,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	ns->ctrlr = ctrlr;
  	ns->id = nsid;
  
  	rc = nvme_ctrlr_identify_ns_async(ns);
  	if (rc) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  	}
  
  	return rc;
  }
  
  static void
  nvme_ctrlr_identify_id_desc_async_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct spdk_nvme_ns *ns = (struct spdk_nvme_ns *)arg;
  	struct spdk_nvme_ctrlr *ctrlr = ns->ctrlr;
  	uint32_t nsid;
  	int rc;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_CONFIGURE_AER,
  				     ctrlr->opts.admin_timeout_ms);
  		return;
  	}
  
  	/* move on to the next active NS */
  	nsid = spdk_nvme_ctrlr_get_next_active_ns(ctrlr, ns->id);
  	ns = spdk_nvme_ctrlr_get_ns(ctrlr, nsid);
  	if (ns == NULL) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_CONFIGURE_AER,
  				     ctrlr->opts.admin_timeout_ms);
  		return;
  	}
  
  	rc = nvme_ctrlr_identify_id_desc_async(ns);
  	if (rc) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  	}
  }
  
  static int
  nvme_ctrlr_identify_id_desc_async(struct spdk_nvme_ns *ns)
  {
  	struct spdk_nvme_ctrlr *ctrlr = ns->ctrlr;
  
  	memset(ns->id_desc_list, 0, sizeof(ns->id_desc_list));
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_ID_DESCS,
  			     ctrlr->opts.admin_timeout_ms);
  	return nvme_ctrlr_cmd_identify(ns->ctrlr, SPDK_NVME_IDENTIFY_NS_ID_DESCRIPTOR_LIST,
  				       0, ns->id, ns->id_desc_list, sizeof(ns->id_desc_list),
  				       nvme_ctrlr_identify_id_desc_async_done, ns);
  }
  
  static int
  nvme_ctrlr_identify_id_desc_namespaces(struct spdk_nvme_ctrlr *ctrlr)
  {
  	uint32_t nsid;
  	struct spdk_nvme_ns *ns;
  	int rc;
  
  	if (ctrlr->vs.raw < SPDK_NVME_VERSION(1, 3, 0) ||
  	    (ctrlr->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Version < 1.3; not attempting to retrieve NS ID Descriptor List\n");
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_CONFIGURE_AER,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	nsid = spdk_nvme_ctrlr_get_first_active_ns(ctrlr);
  	ns = spdk_nvme_ctrlr_get_ns(ctrlr, nsid);
  	if (ns == NULL) {
  		/* No active NS, move on to the next state */
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_CONFIGURE_AER,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	rc = nvme_ctrlr_identify_id_desc_async(ns);
  	if (rc) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  	}
  
  	return rc;
  }
  
  static void
  nvme_ctrlr_update_nvmf_ioccsz(struct spdk_nvme_ctrlr *ctrlr)
  {
  	if (ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_RDMA ||
  	    ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_TCP ||
  	    ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_FC) {
  		if (ctrlr->cdata.nvmf_specific.ioccsz < 4) {
  			SPDK_ERRLOG("Incorrect IOCCSZ %u, the minimum value should be 4\n",
  				    ctrlr->cdata.nvmf_specific.ioccsz);
  			ctrlr->cdata.nvmf_specific.ioccsz = 4;
  			assert(0);
  		}
  		ctrlr->ioccsz_bytes = ctrlr->cdata.nvmf_specific.ioccsz * 16 - sizeof(struct spdk_nvme_cmd);
  		ctrlr->icdoff = ctrlr->cdata.nvmf_specific.icdoff;
  	}
  }
  
  static void
  nvme_ctrlr_set_num_queues_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	uint32_t cq_allocated, sq_allocated, min_allocated, i;
  	struct spdk_nvme_ctrlr *ctrlr = (struct spdk_nvme_ctrlr *)arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		SPDK_ERRLOG("Set Features - Number of Queues failed!\n");
  		ctrlr->opts.num_io_queues = 0;
  	} else {
  		/*
  		 * Data in cdw0 is 0-based.
  		 * Lower 16-bits indicate number of submission queues allocated.
  		 * Upper 16-bits indicate number of completion queues allocated.
  		 */
  		sq_allocated = (cpl->cdw0 & 0xFFFF) + 1;
  		cq_allocated = (cpl->cdw0 >> 16) + 1;
  
  		/*
  		 * For 1:1 queue mapping, set number of allocated queues to be minimum of
  		 * submission and completion queues.
  		 */
  		min_allocated = spdk_min(sq_allocated, cq_allocated);
  
  		/* Set number of queues to be minimum of requested and actually allocated. */
  		ctrlr->opts.num_io_queues = spdk_min(min_allocated, ctrlr->opts.num_io_queues);
  	}
  
  	ctrlr->free_io_qids = spdk_bit_array_create(ctrlr->opts.num_io_queues + 1);
  	if (ctrlr->free_io_qids == NULL) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return;
  	}
  
  	/* Initialize list of free I/O queue IDs. QID 0 is the admin queue. */
  	spdk_bit_array_clear(ctrlr->free_io_qids, 0);
  	for (i = 1; i <= ctrlr->opts.num_io_queues; i++) {
  		spdk_bit_array_set(ctrlr->free_io_qids, i);
  	}
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_CONSTRUCT_NS,
  			     ctrlr->opts.admin_timeout_ms);
  }
  
  static int
  nvme_ctrlr_set_num_queues(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc;
  
  	if (ctrlr->opts.num_io_queues > SPDK_NVME_MAX_IO_QUEUES) {
  		SPDK_NOTICELOG("Limiting requested num_io_queues %u to max %d\n",
  			       ctrlr->opts.num_io_queues, SPDK_NVME_MAX_IO_QUEUES);
  		ctrlr->opts.num_io_queues = SPDK_NVME_MAX_IO_QUEUES;
  	} else if (ctrlr->opts.num_io_queues < 1) {
  		SPDK_NOTICELOG("Requested num_io_queues 0, increasing to 1\n");
  		ctrlr->opts.num_io_queues = 1;
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_SET_NUM_QUEUES,
  			     ctrlr->opts.admin_timeout_ms);
  
  	rc = nvme_ctrlr_cmd_set_num_queues(ctrlr, ctrlr->opts.num_io_queues,
  					   nvme_ctrlr_set_num_queues_done, ctrlr);
  	if (rc != 0) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return rc;
  	}
  
  	return 0;
  }
  
  static void
  nvme_ctrlr_set_keep_alive_timeout_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	uint32_t keep_alive_interval_ms;
  	struct spdk_nvme_ctrlr *ctrlr = (struct spdk_nvme_ctrlr *)arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		SPDK_ERRLOG("Keep alive timeout Get Feature failed: SC %x SCT %x\n",
  			    cpl->status.sc, cpl->status.sct);
  		ctrlr->opts.keep_alive_timeout_ms = 0;
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return;
  	}
  
  	if (ctrlr->opts.keep_alive_timeout_ms != cpl->cdw0) {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Controller adjusted keep alive timeout to %u ms\n",
  			      cpl->cdw0);
  	}
  
  	ctrlr->opts.keep_alive_timeout_ms = cpl->cdw0;
  
  	keep_alive_interval_ms = ctrlr->opts.keep_alive_timeout_ms / 2;
  	if (keep_alive_interval_ms == 0) {
  		keep_alive_interval_ms = 1;
  	}
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "Sending keep alive every %u ms\n", keep_alive_interval_ms);
  
  	ctrlr->keep_alive_interval_ticks = (keep_alive_interval_ms * spdk_get_ticks_hz()) / UINT64_C(1000);
  
  	/* Schedule the first Keep Alive to be sent as soon as possible. */
  	ctrlr->next_keep_alive_tick = spdk_get_ticks();
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_HOST_ID,
  			     ctrlr->opts.admin_timeout_ms);
  }
  
  static int
  nvme_ctrlr_set_keep_alive_timeout(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc;
  
  	if (ctrlr->opts.keep_alive_timeout_ms == 0) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_HOST_ID,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	if (ctrlr->cdata.kas == 0) {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Controller KAS is 0 - not enabling Keep Alive\n");
  		ctrlr->opts.keep_alive_timeout_ms = 0;
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_HOST_ID,
  				     ctrlr->opts.admin_timeout_ms);
  		return 0;
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_KEEP_ALIVE_TIMEOUT,
  			     ctrlr->opts.admin_timeout_ms);
  
  	/* Retrieve actual keep alive timeout, since the controller may have adjusted it. */
  	rc = spdk_nvme_ctrlr_cmd_get_feature(ctrlr, SPDK_NVME_FEAT_KEEP_ALIVE_TIMER, 0, NULL, 0,
  					     nvme_ctrlr_set_keep_alive_timeout_done, ctrlr);
  	if (rc != 0) {
  		SPDK_ERRLOG("Keep alive timeout Get Feature failed: %d\n", rc);
  		ctrlr->opts.keep_alive_timeout_ms = 0;
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return rc;
  	}
  
  	return 0;
  }
  
  static void
  nvme_ctrlr_set_host_id_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct spdk_nvme_ctrlr *ctrlr = (struct spdk_nvme_ctrlr *)arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		/*
  		 * Treat Set Features - Host ID failure as non-fatal, since the Host ID feature
  		 * is optional.
  		 */
  		SPDK_WARNLOG("Set Features - Host ID failed: SC 0x%x SCT 0x%x\n",
  			     cpl->status.sc, cpl->status.sct);
  	} else {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Set Features - Host ID was successful\n");
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_READY, NVME_TIMEOUT_INFINITE);
  }
  
  static int
  nvme_ctrlr_set_host_id(struct spdk_nvme_ctrlr *ctrlr)
  {
  	uint8_t *host_id;
  	uint32_t host_id_size;
  	int rc;
  
  	if (ctrlr->trid.trtype != SPDK_NVME_TRANSPORT_PCIE) {
  		/*
  		 * NVMe-oF sends the host ID during Connect and doesn't allow
  		 * Set Features - Host Identifier after Connect, so we don't need to do anything here.
  		 */
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "NVMe-oF transport - not sending Set Features - Host ID\n");
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_READY, NVME_TIMEOUT_INFINITE);
  		return 0;
  	}
  
  	if (ctrlr->cdata.ctratt.host_id_exhid_supported) {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Using 128-bit extended host identifier\n");
  		host_id = ctrlr->opts.extended_host_id;
  		host_id_size = sizeof(ctrlr->opts.extended_host_id);
  	} else {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Using 64-bit host identifier\n");
  		host_id = ctrlr->opts.host_id;
  		host_id_size = sizeof(ctrlr->opts.host_id);
  	}
  
  	/* If the user specified an all-zeroes host identifier, don't send the command. */
  	if (spdk_mem_all_zero(host_id, host_id_size)) {
  		SPDK_DEBUGLOG(SPDK_LOG_NVME,
  			      "User did not specify host ID - not sending Set Features - Host ID\n");
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_READY, NVME_TIMEOUT_INFINITE);
  		return 0;
  	}
  
  	SPDK_LOGDUMP(SPDK_LOG_NVME, "host_id", host_id, host_id_size);
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_HOST_ID,
  			     ctrlr->opts.admin_timeout_ms);
  
  	rc = nvme_ctrlr_cmd_set_host_id(ctrlr, host_id, host_id_size, nvme_ctrlr_set_host_id_done, ctrlr);
  	if (rc != 0) {
  		SPDK_ERRLOG("Set Features - Host ID failed: %d\n", rc);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return rc;
  	}
  
  	return 0;
  }
  
  static void
  nvme_ctrlr_destruct_namespaces(struct spdk_nvme_ctrlr *ctrlr)
  {
  	if (ctrlr->ns) {
  		uint32_t i, num_ns = ctrlr->num_ns;
  
  		for (i = 0; i < num_ns; i++) {
  			nvme_ns_destruct(&ctrlr->ns[i]);
  		}
  
  		spdk_free(ctrlr->ns);
  		ctrlr->ns = NULL;
  		ctrlr->num_ns = 0;
  	}
  
  	if (ctrlr->nsdata) {
  		spdk_free(ctrlr->nsdata);
  		ctrlr->nsdata = NULL;
  	}
  
  	spdk_free(ctrlr->active_ns_list);
  	ctrlr->active_ns_list = NULL;
  }
  
  static void
  nvme_ctrlr_update_namespaces(struct spdk_nvme_ctrlr *ctrlr)
  {
  	uint32_t i, nn = ctrlr->cdata.nn;
  	struct spdk_nvme_ns_data *nsdata;
  	bool ns_is_active;
  
  	for (i = 0; i < nn; i++) {
  		struct spdk_nvme_ns	*ns = &ctrlr->ns[i];
  		uint32_t		nsid = i + 1;
  
  		nsdata = &ctrlr->nsdata[nsid - 1];
  		ns_is_active = spdk_nvme_ctrlr_is_active_ns(ctrlr, nsid);
  
  		if (nsdata->ncap && ns_is_active) {
  			if (nvme_ns_update(ns) != 0) {
  				SPDK_ERRLOG("Failed to update active NS %u\n", nsid);
  				continue;
  			}
  		}
  
  		if ((nsdata->ncap == 0) && ns_is_active) {
  			if (nvme_ns_construct(ns, nsid, ctrlr) != 0) {
  				continue;
  			}
  		}
  
  		if (nsdata->ncap && !ns_is_active) {
  			nvme_ns_destruct(ns);
  		}
  	}
  }
  
  static int
  nvme_ctrlr_construct_namespaces(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc = 0;
  	uint32_t nn = ctrlr->cdata.nn;
  
  	/* ctrlr->num_ns may be 0 (startup) or a different number of namespaces (reset),
  	 * so check if we need to reallocate.
  	 */
  	if (nn != ctrlr->num_ns) {
  		nvme_ctrlr_destruct_namespaces(ctrlr);
  
  		if (nn == 0) {
  			SPDK_WARNLOG("controller has 0 namespaces\n");
  			return 0;
  		}
  
  		ctrlr->ns = spdk_zmalloc(nn * sizeof(struct spdk_nvme_ns), 64, NULL,
  					 SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_SHARE);
  		if (ctrlr->ns == NULL) {
  			rc = -ENOMEM;
  			goto fail;
  		}
  
  		ctrlr->nsdata = spdk_zmalloc(nn * sizeof(struct spdk_nvme_ns_data), 64,
  					     NULL, SPDK_ENV_SOCKET_ID_ANY,
  					     SPDK_MALLOC_SHARE | SPDK_MALLOC_DMA);
  		if (ctrlr->nsdata == NULL) {
  			rc = -ENOMEM;
  			goto fail;
  		}
  
  		ctrlr->num_ns = nn;
  	}
  
  	return 0;
  
  fail:
  	nvme_ctrlr_destruct_namespaces(ctrlr);
  	return rc;
  }
  
  static void
  nvme_ctrlr_async_event_cb(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct nvme_async_event_request	*aer = arg;
  	struct spdk_nvme_ctrlr		*ctrlr = aer->ctrlr;
  	struct spdk_nvme_ctrlr_process	*active_proc;
  	union spdk_nvme_async_event_completion	event;
  	int					rc;
  
  	if (cpl->status.sct == SPDK_NVME_SCT_GENERIC &&
  	    cpl->status.sc == SPDK_NVME_SC_ABORTED_SQ_DELETION) {
  		/*
  		 *  This is simulated when controller is being shut down, to
  		 *  effectively abort outstanding asynchronous event requests
  		 *  and make sure all memory is freed.  Do not repost the
  		 *  request in this case.
  		 */
  		return;
  	}
  
  	if (cpl->status.sct == SPDK_NVME_SCT_COMMAND_SPECIFIC &&
  	    cpl->status.sc == SPDK_NVME_SC_ASYNC_EVENT_REQUEST_LIMIT_EXCEEDED) {
  		/*
  		 *  SPDK will only send as many AERs as the device says it supports,
  		 *  so this status code indicates an out-of-spec device.  Do not repost
  		 *  the request in this case.
  		 */
  		SPDK_ERRLOG("Controller appears out-of-spec for asynchronous event request\n"
  			    "handling.  Do not repost this AER.\n");
  		return;
  	}
  
  	event.raw = cpl->cdw0;
  	if ((event.bits.async_event_type == SPDK_NVME_ASYNC_EVENT_TYPE_NOTICE) &&
  	    (event.bits.async_event_info == SPDK_NVME_ASYNC_EVENT_NS_ATTR_CHANGED)) {
  		rc = nvme_ctrlr_identify_active_ns(ctrlr);
  		if (rc) {
  			return;
  		}
  		nvme_ctrlr_update_namespaces(ctrlr);
  	}
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc && active_proc->aer_cb_fn) {
  		active_proc->aer_cb_fn(active_proc->aer_cb_arg, cpl);
  	}
  
  	/* If the ctrlr was removed or in the destruct state, we should not send aer again */
  	if (ctrlr->is_removed || ctrlr->is_destructed) {
  		return;
  	}
  
  	/*
  	 * Repost another asynchronous event request to replace the one
  	 *  that just completed.
  	 */
  	if (nvme_ctrlr_construct_and_submit_aer(ctrlr, aer)) {
  		/*
  		 * We can't do anything to recover from a failure here,
  		 * so just print a warning message and leave the AER unsubmitted.
  		 */
  		SPDK_ERRLOG("resubmitting AER failed!\n");
  	}
  }
  
  static int
  nvme_ctrlr_construct_and_submit_aer(struct spdk_nvme_ctrlr *ctrlr,
  				    struct nvme_async_event_request *aer)
  {
  	struct nvme_request *req;
  
  	aer->ctrlr = ctrlr;
  	req = nvme_allocate_request_null(ctrlr->adminq, nvme_ctrlr_async_event_cb, aer);
  	aer->req = req;
  	if (req == NULL) {
  		return -1;
  	}
  
  	req->cmd.opc = SPDK_NVME_OPC_ASYNC_EVENT_REQUEST;
  	return nvme_ctrlr_submit_admin_request(ctrlr, req);
  }
  
  static void
  nvme_ctrlr_configure_aer_done(void *arg, const struct spdk_nvme_cpl *cpl)
  {
  	struct nvme_async_event_request		*aer;
  	int					rc;
  	uint32_t				i;
  	struct spdk_nvme_ctrlr *ctrlr =	(struct spdk_nvme_ctrlr *)arg;
  
  	if (spdk_nvme_cpl_is_error(cpl)) {
  		SPDK_NOTICELOG("nvme_ctrlr_configure_aer failed!\n");
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_SUPPORTED_LOG_PAGES,
  				     ctrlr->opts.admin_timeout_ms);
  		return;
  	}
  
  	/* aerl is a zero-based value, so we need to add 1 here. */
  	ctrlr->num_aers = spdk_min(NVME_MAX_ASYNC_EVENTS, (ctrlr->cdata.aerl + 1));
  
  	for (i = 0; i < ctrlr->num_aers; i++) {
  		aer = &ctrlr->aer[i];
  		rc = nvme_ctrlr_construct_and_submit_aer(ctrlr, aer);
  		if (rc) {
  			SPDK_ERRLOG("nvme_ctrlr_construct_and_submit_aer failed!\n");
  			nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  			return;
  		}
  	}
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_SUPPORTED_LOG_PAGES,
  			     ctrlr->opts.admin_timeout_ms);
  }
  
  static int
  nvme_ctrlr_configure_aer(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_feat_async_event_configuration	config;
  	int						rc;
  
  	config.raw = 0;
  	config.bits.crit_warn.bits.available_spare = 1;
  	config.bits.crit_warn.bits.temperature = 1;
  	config.bits.crit_warn.bits.device_reliability = 1;
  	config.bits.crit_warn.bits.read_only = 1;
  	config.bits.crit_warn.bits.volatile_memory_backup = 1;
  
  	if (ctrlr->vs.raw >= SPDK_NVME_VERSION(1, 2, 0)) {
  		if (ctrlr->cdata.oaes.ns_attribute_notices) {
  			config.bits.ns_attr_notice = 1;
  		}
  		if (ctrlr->cdata.oaes.fw_activation_notices) {
  			config.bits.fw_activation_notice = 1;
  		}
  	}
  	if (ctrlr->vs.raw >= SPDK_NVME_VERSION(1, 3, 0) && ctrlr->cdata.lpa.telemetry) {
  		config.bits.telemetry_log_notice = 1;
  	}
  
  	nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_WAIT_FOR_CONFIGURE_AER,
  			     ctrlr->opts.admin_timeout_ms);
  
  	rc = nvme_ctrlr_cmd_set_async_event_config(ctrlr, config,
  			nvme_ctrlr_configure_aer_done,
  			ctrlr);
  	if (rc != 0) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ERROR, NVME_TIMEOUT_INFINITE);
  		return rc;
  	}
  
  	return 0;
  }
  
  struct spdk_nvme_ctrlr_process *
  spdk_nvme_ctrlr_get_process(struct spdk_nvme_ctrlr *ctrlr, pid_t pid)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  
  	TAILQ_FOREACH(active_proc, &ctrlr->active_procs, tailq) {
  		if (active_proc->pid == pid) {
  			return active_proc;
  		}
  	}
  
  	return NULL;
  }
  
  struct spdk_nvme_ctrlr_process *
  spdk_nvme_ctrlr_get_current_process(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return spdk_nvme_ctrlr_get_process(ctrlr, getpid());
  }
  
  /**
   * This function will be called when a process is using the controller.
   *  1. For the primary process, it is called when constructing the controller.
   *  2. For the secondary process, it is called at probing the controller.
   * Note: will check whether the process is already added for the same process.
   */
  int
  nvme_ctrlr_add_process(struct spdk_nvme_ctrlr *ctrlr, void *devhandle)
  {
  	struct spdk_nvme_ctrlr_process	*ctrlr_proc;
  	pid_t				pid = getpid();
  
  	/* Check whether the process is already added or not */
  	if (spdk_nvme_ctrlr_get_process(ctrlr, pid)) {
  		return 0;
  	}
  
  	/* Initialize the per process properties for this ctrlr */
  	ctrlr_proc = spdk_zmalloc(sizeof(struct spdk_nvme_ctrlr_process),
  				  64, NULL, SPDK_ENV_SOCKET_ID_ANY, SPDK_MALLOC_SHARE);
  	if (ctrlr_proc == NULL) {
  		SPDK_ERRLOG("failed to allocate memory to track the process props\n");
  
  		return -1;
  	}
  
  	ctrlr_proc->is_primary = spdk_process_is_primary();
  	ctrlr_proc->pid = pid;
  	STAILQ_INIT(&ctrlr_proc->active_reqs);
  	ctrlr_proc->devhandle = devhandle;
  	ctrlr_proc->ref = 0;
  	TAILQ_INIT(&ctrlr_proc->allocated_io_qpairs);
  
  	TAILQ_INSERT_TAIL(&ctrlr->active_procs, ctrlr_proc, tailq);
  
  	return 0;
  }
  
  /**
   * This function will be called when the process detaches the controller.
   * Note: the ctrlr_lock must be held when calling this function.
   */
  static void
  nvme_ctrlr_remove_process(struct spdk_nvme_ctrlr *ctrlr,
  			  struct spdk_nvme_ctrlr_process *proc)
  {
  	struct spdk_nvme_qpair	*qpair, *tmp_qpair;
  
  	assert(STAILQ_EMPTY(&proc->active_reqs));
  
  	TAILQ_FOREACH_SAFE(qpair, &proc->allocated_io_qpairs, per_process_tailq, tmp_qpair) {
  		spdk_nvme_ctrlr_free_io_qpair(qpair);
  	}
  
  	TAILQ_REMOVE(&ctrlr->active_procs, proc, tailq);
  
  	if (ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_PCIE) {
  		spdk_pci_device_detach(proc->devhandle);
  	}
  
  	spdk_free(proc);
  }
  
  /**
   * This function will be called when the process exited unexpectedly
   *  in order to free any incomplete nvme request, allocated IO qpairs
   *  and allocated memory.
   * Note: the ctrlr_lock must be held when calling this function.
   */
  static void
  nvme_ctrlr_cleanup_process(struct spdk_nvme_ctrlr_process *proc)
  {
  	struct nvme_request	*req, *tmp_req;
  	struct spdk_nvme_qpair	*qpair, *tmp_qpair;
  
  	STAILQ_FOREACH_SAFE(req, &proc->active_reqs, stailq, tmp_req) {
  		STAILQ_REMOVE(&proc->active_reqs, req, nvme_request, stailq);
  
  		assert(req->pid == proc->pid);
  
  		nvme_free_request(req);
  	}
  
  	TAILQ_FOREACH_SAFE(qpair, &proc->allocated_io_qpairs, per_process_tailq, tmp_qpair) {
  		TAILQ_REMOVE(&proc->allocated_io_qpairs, qpair, per_process_tailq);
  
  		/*
  		 * The process may have been killed while some qpairs were in their
  		 *  completion context.  Clear that flag here to allow these IO
  		 *  qpairs to be deleted.
  		 */
  		qpair->in_completion_context = 0;
  
  		qpair->no_deletion_notification_needed = 1;
  
  		spdk_nvme_ctrlr_free_io_qpair(qpair);
  	}
  
  	spdk_free(proc);
  }
  
  /**
   * This function will be called when destructing the controller.
   *  1. There is no more admin request on this controller.
   *  2. Clean up any left resource allocation when its associated process is gone.
   */
  void
  nvme_ctrlr_free_processes(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc, *tmp;
  
  	/* Free all the processes' properties and make sure no pending admin IOs */
  	TAILQ_FOREACH_SAFE(active_proc, &ctrlr->active_procs, tailq, tmp) {
  		TAILQ_REMOVE(&ctrlr->active_procs, active_proc, tailq);
  
  		assert(STAILQ_EMPTY(&active_proc->active_reqs));
  
  		spdk_free(active_proc);
  	}
  }
  
  /**
   * This function will be called when any other process attaches or
   *  detaches the controller in order to cleanup those unexpectedly
   *  terminated processes.
   * Note: the ctrlr_lock must be held when calling this function.
   */
  static int
  nvme_ctrlr_remove_inactive_proc(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc, *tmp;
  	int				active_proc_count = 0;
  
  	TAILQ_FOREACH_SAFE(active_proc, &ctrlr->active_procs, tailq, tmp) {
  		if ((kill(active_proc->pid, 0) == -1) && (errno == ESRCH)) {
  			SPDK_ERRLOG("process %d terminated unexpected\n", active_proc->pid);
  
  			TAILQ_REMOVE(&ctrlr->active_procs, active_proc, tailq);
  
  			nvme_ctrlr_cleanup_process(active_proc);
  		} else {
  			active_proc_count++;
  		}
  	}
  
  	return active_proc_count;
  }
  
  void
  nvme_ctrlr_proc_get_ref(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	nvme_ctrlr_remove_inactive_proc(ctrlr);
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc) {
  		active_proc->ref++;
  	}
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  void
  nvme_ctrlr_proc_put_ref(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  	int				proc_count;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	proc_count = nvme_ctrlr_remove_inactive_proc(ctrlr);
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc) {
  		active_proc->ref--;
  		assert(active_proc->ref >= 0);
  
  		/*
  		 * The last active process will be removed at the end of
  		 * the destruction of the controller.
  		 */
  		if (active_proc->ref == 0 && proc_count != 1) {
  			nvme_ctrlr_remove_process(ctrlr, active_proc);
  		}
  	}
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  int
  nvme_ctrlr_get_ref_count(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  	int				ref = 0;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	nvme_ctrlr_remove_inactive_proc(ctrlr);
  
  	TAILQ_FOREACH(active_proc, &ctrlr->active_procs, tailq) {
  		ref += active_proc->ref;
  	}
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	return ref;
  }
  
  /**
   *  Get the PCI device handle which is only visible to its associated process.
   */
  struct spdk_pci_device *
  nvme_ctrlr_proc_get_devhandle(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  	struct spdk_pci_device		*devhandle = NULL;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc) {
  		devhandle = active_proc->devhandle;
  	}
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	return devhandle;
  }
  
  /**
   * This function will be called repeatedly during initialization until the controller is ready.
   */
  int
  nvme_ctrlr_process_init(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_cc_register cc;
  	union spdk_nvme_csts_register csts;
  	uint32_t ready_timeout_in_ms;
  	int rc = 0;
  
  	/*
  	 * May need to avoid accessing any register on the target controller
  	 * for a while. Return early without touching the FSM.
  	 * Check sleep_timeout_tsc > 0 for unit test.
  	 */
  	if ((ctrlr->sleep_timeout_tsc > 0) &&
  	    (spdk_get_ticks() <= ctrlr->sleep_timeout_tsc)) {
  		return 0;
  	}
  	ctrlr->sleep_timeout_tsc = 0;
  
  	if (nvme_ctrlr_get_cc(ctrlr, &cc) ||
  	    nvme_ctrlr_get_csts(ctrlr, &csts)) {
  		if (ctrlr->state_timeout_tsc != NVME_TIMEOUT_INFINITE) {
  			/* While a device is resetting, it may be unable to service MMIO reads
  			 * temporarily. Allow for this case.
  			 */
  			SPDK_ERRLOG("Get registers failed while waiting for CSTS.RDY == 0\n");
  			goto init_timeout;
  		}
  		SPDK_ERRLOG("Failed to read CC and CSTS in state %d\n", ctrlr->state);
  		return -EIO;
  	}
  
  	ready_timeout_in_ms = 500 * ctrlr->cap.bits.to;
  
  	/*
  	 * Check if the current initialization step is done or has timed out.
  	 */
  	switch (ctrlr->state) {
  	case NVME_CTRLR_STATE_INIT_DELAY:
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_INIT, ready_timeout_in_ms);
  		if (ctrlr->quirks & NVME_QUIRK_DELAY_BEFORE_INIT) {
  			/*
  			 * Controller may need some delay before it's enabled.
  			 *
  			 * This is a workaround for an issue where the PCIe-attached NVMe controller
  			 * is not ready after VFIO reset. We delay the initialization rather than the
  			 * enabling itself, because this is required only for the very first enabling
  			 * - directly after a VFIO reset.
  			 */
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "Adding 2 second delay before initializing the controller\n");
  			ctrlr->sleep_timeout_tsc = spdk_get_ticks() + (2000 * spdk_get_ticks_hz() / 1000);
  		}
  		break;
  
  	case NVME_CTRLR_STATE_INIT:
  		/* Begin the hardware initialization by making sure the controller is disabled. */
  		if (cc.bits.en) {
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "CC.EN = 1\n");
  			/*
  			 * Controller is currently enabled. We need to disable it to cause a reset.
  			 *
  			 * If CC.EN = 1 && CSTS.RDY = 0, the controller is in the process of becoming ready.
  			 *  Wait for the ready bit to be 1 before disabling the controller.
  			 */
  			if (csts.bits.rdy == 0) {
  				SPDK_DEBUGLOG(SPDK_LOG_NVME, "CC.EN = 1 && CSTS.RDY = 0 - waiting for reset to complete\n");
  				nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_1, ready_timeout_in_ms);
  				return 0;
  			}
  
  			/* CC.EN = 1 && CSTS.RDY == 1, so we can immediately disable the controller. */
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "Setting CC.EN = 0\n");
  			cc.bits.en = 0;
  			if (nvme_ctrlr_set_cc(ctrlr, &cc)) {
  				SPDK_ERRLOG("set_cc() failed\n");
  				return -EIO;
  			}
  			nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_0, ready_timeout_in_ms);
  
  			/*
  			 * Wait 2.5 seconds before accessing PCI registers.
  			 * Not using sleep() to avoid blocking other controller's initialization.
  			 */
  			if (ctrlr->quirks & NVME_QUIRK_DELAY_BEFORE_CHK_RDY) {
  				SPDK_DEBUGLOG(SPDK_LOG_NVME, "Applying quirk: delay 2.5 seconds before reading registers\n");
  				ctrlr->sleep_timeout_tsc = spdk_get_ticks() + (2500 * spdk_get_ticks_hz() / 1000);
  			}
  			return 0;
  		} else {
  			if (csts.bits.rdy == 1) {
  				SPDK_DEBUGLOG(SPDK_LOG_NVME, "CC.EN = 0 && CSTS.RDY = 1 - waiting for shutdown to complete\n");
  			}
  
  			nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_0, ready_timeout_in_ms);
  			return 0;
  		}
  		break;
  
  	case NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_1:
  		if (csts.bits.rdy == 1) {
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "CC.EN = 1 && CSTS.RDY = 1 - disabling controller\n");
  			/* CC.EN = 1 && CSTS.RDY = 1, so we can set CC.EN = 0 now. */
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "Setting CC.EN = 0\n");
  			cc.bits.en = 0;
  			if (nvme_ctrlr_set_cc(ctrlr, &cc)) {
  				SPDK_ERRLOG("set_cc() failed\n");
  				return -EIO;
  			}
  			nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_0, ready_timeout_in_ms);
  			return 0;
  		}
  		break;
  
  	case NVME_CTRLR_STATE_DISABLE_WAIT_FOR_READY_0:
  		if (csts.bits.rdy == 0) {
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "CC.EN = 0 && CSTS.RDY = 0\n");
  			nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ENABLE, ready_timeout_in_ms);
  			/*
  			 * Delay 100us before setting CC.EN = 1.  Some NVMe SSDs miss CC.EN getting
  			 *  set to 1 if it is too soon after CSTS.RDY is reported as 0.
  			 */
  			spdk_delay_us(100);
  			return 0;
  		}
  		break;
  
  	case NVME_CTRLR_STATE_ENABLE:
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Setting CC.EN = 1\n");
  		rc = nvme_ctrlr_enable(ctrlr);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_ENABLE_WAIT_FOR_READY_1, ready_timeout_in_ms);
  		return rc;
  
  	case NVME_CTRLR_STATE_ENABLE_WAIT_FOR_READY_1:
  		if (csts.bits.rdy == 1) {
  			SPDK_DEBUGLOG(SPDK_LOG_NVME, "CC.EN = 1 && CSTS.RDY = 1 - controller is ready\n");
  			/*
  			 * The controller has been enabled.
  			 *  Perform the rest of initialization serially.
  			 */
  			nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_RESET_ADMIN_QUEUE,
  					     ctrlr->opts.admin_timeout_ms);
  			return 0;
  		}
  		break;
  
  	case NVME_CTRLR_STATE_RESET_ADMIN_QUEUE:
  		nvme_transport_qpair_reset(ctrlr->adminq);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_IDENTIFY,
  				     ctrlr->opts.admin_timeout_ms);
  		break;
  
  	case NVME_CTRLR_STATE_IDENTIFY:
  		rc = nvme_ctrlr_identify(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_SET_NUM_QUEUES:
  		nvme_ctrlr_update_nvmf_ioccsz(ctrlr);
  		rc = nvme_ctrlr_set_num_queues(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_SET_NUM_QUEUES:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_CONSTRUCT_NS:
  		rc = nvme_ctrlr_construct_namespaces(ctrlr);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_IDENTIFY_ACTIVE_NS,
  				     ctrlr->opts.admin_timeout_ms);
  		break;
  
  	case NVME_CTRLR_STATE_IDENTIFY_ACTIVE_NS:
  		_nvme_ctrlr_identify_active_ns(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_ACTIVE_NS:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_IDENTIFY_NS:
  		rc = nvme_ctrlr_identify_namespaces(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_NS:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_IDENTIFY_ID_DESCS:
  		rc = nvme_ctrlr_identify_id_desc_namespaces(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_IDENTIFY_ID_DESCS:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_CONFIGURE_AER:
  		rc = nvme_ctrlr_configure_aer(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_CONFIGURE_AER:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_SET_SUPPORTED_LOG_PAGES:
  		rc = nvme_ctrlr_set_supported_log_pages(ctrlr);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_SUPPORTED_FEATURES,
  				     ctrlr->opts.admin_timeout_ms);
  		break;
  
  	case NVME_CTRLR_STATE_SET_SUPPORTED_FEATURES:
  		nvme_ctrlr_set_supported_features(ctrlr);
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_SET_DB_BUF_CFG,
  				     ctrlr->opts.admin_timeout_ms);
  		break;
  
  	case NVME_CTRLR_STATE_SET_DB_BUF_CFG:
  		rc = nvme_ctrlr_set_doorbell_buffer_config(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_DB_BUF_CFG:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_SET_KEEP_ALIVE_TIMEOUT:
  		rc = nvme_ctrlr_set_keep_alive_timeout(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_KEEP_ALIVE_TIMEOUT:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_SET_HOST_ID:
  		rc = nvme_ctrlr_set_host_id(ctrlr);
  		break;
  
  	case NVME_CTRLR_STATE_WAIT_FOR_HOST_ID:
  		spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  		break;
  
  	case NVME_CTRLR_STATE_READY:
  		SPDK_DEBUGLOG(SPDK_LOG_NVME, "Ctrlr already in ready state\n");
  		return 0;
  
  	case NVME_CTRLR_STATE_ERROR:
  		SPDK_ERRLOG("Ctrlr %s is in error state\n", ctrlr->trid.traddr);
  		return -1;
  
  	default:
  		assert(0);
  		return -1;
  	}
  
  init_timeout:
  	if (ctrlr->state_timeout_tsc != NVME_TIMEOUT_INFINITE &&
  	    spdk_get_ticks() > ctrlr->state_timeout_tsc) {
  		SPDK_ERRLOG("Initialization timed out in state %d\n", ctrlr->state);
  		return -1;
  	}
  
  	return rc;
  }
  
  int
  nvme_robust_mutex_init_recursive_shared(pthread_mutex_t *mtx)
  {
  	pthread_mutexattr_t attr;
  	int rc = 0;
  
  	if (pthread_mutexattr_init(&attr)) {
  		return -1;
  	}
  	if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE) ||
  #ifndef __FreeBSD__
  	    pthread_mutexattr_setrobust(&attr, PTHREAD_MUTEX_ROBUST) ||
  	    pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED) ||
  #endif
  	    pthread_mutex_init(mtx, &attr)) {
  		rc = -1;
  	}
  	pthread_mutexattr_destroy(&attr);
  	return rc;
  }
  
  int
  nvme_ctrlr_construct(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc;
  
  	if (ctrlr->trid.trtype == SPDK_NVME_TRANSPORT_PCIE) {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_INIT_DELAY, NVME_TIMEOUT_INFINITE);
  	} else {
  		nvme_ctrlr_set_state(ctrlr, NVME_CTRLR_STATE_INIT, NVME_TIMEOUT_INFINITE);
  	}
  
  	if (ctrlr->opts.admin_queue_size > SPDK_NVME_ADMIN_QUEUE_MAX_ENTRIES) {
  		SPDK_ERRLOG("admin_queue_size %u exceeds max defined by NVMe spec, use max value\n",
  			    ctrlr->opts.admin_queue_size);
  		ctrlr->opts.admin_queue_size = SPDK_NVME_ADMIN_QUEUE_MAX_ENTRIES;
  	}
  
  	if (ctrlr->opts.admin_queue_size < SPDK_NVME_ADMIN_QUEUE_MIN_ENTRIES) {
  		SPDK_ERRLOG("admin_queue_size %u is less than minimum defined by NVMe spec, use min value\n",
  			    ctrlr->opts.admin_queue_size);
  		ctrlr->opts.admin_queue_size = SPDK_NVME_ADMIN_QUEUE_MIN_ENTRIES;
  	}
  
  	ctrlr->flags = 0;
  	ctrlr->free_io_qids = NULL;
  	ctrlr->is_resetting = false;
  	ctrlr->is_failed = false;
  	ctrlr->is_destructed = false;
  
  	TAILQ_INIT(&ctrlr->active_io_qpairs);
  	STAILQ_INIT(&ctrlr->queued_aborts);
  	ctrlr->outstanding_aborts = 0;
  
  	rc = nvme_robust_mutex_init_recursive_shared(&ctrlr->ctrlr_lock);
  	if (rc != 0) {
  		return rc;
  	}
  
  	TAILQ_INIT(&ctrlr->active_procs);
  
  	return rc;
  }
  
  /* This function should be called once at ctrlr initialization to set up constant properties. */
  void
  nvme_ctrlr_init_cap(struct spdk_nvme_ctrlr *ctrlr, const union spdk_nvme_cap_register *cap,
  		    const union spdk_nvme_vs_register *vs)
  {
  	ctrlr->cap = *cap;
  	ctrlr->vs = *vs;
  
  	if (ctrlr->cap.bits.ams & SPDK_NVME_CAP_AMS_WRR) {
  		ctrlr->flags |= SPDK_NVME_CTRLR_WRR_SUPPORTED;
  	}
  
  	ctrlr->min_page_size = 1u << (12 + ctrlr->cap.bits.mpsmin);
  
  	/* For now, always select page_size == min_page_size. */
  	ctrlr->page_size = ctrlr->min_page_size;
  
  	ctrlr->opts.io_queue_size = spdk_max(ctrlr->opts.io_queue_size, SPDK_NVME_IO_QUEUE_MIN_ENTRIES);
  	ctrlr->opts.io_queue_size = spdk_min(ctrlr->opts.io_queue_size, MAX_IO_QUEUE_ENTRIES);
  	ctrlr->opts.io_queue_size = spdk_min(ctrlr->opts.io_queue_size, ctrlr->cap.bits.mqes + 1u);
  
  	ctrlr->opts.io_queue_requests = spdk_max(ctrlr->opts.io_queue_requests, ctrlr->opts.io_queue_size);
  }
  
  void
  nvme_ctrlr_destruct_finish(struct spdk_nvme_ctrlr *ctrlr)
  {
  	pthread_mutex_destroy(&ctrlr->ctrlr_lock);
  }
  
  void
  nvme_ctrlr_destruct(struct spdk_nvme_ctrlr *ctrlr)
  {
  	struct spdk_nvme_qpair *qpair, *tmp;
  
  	SPDK_DEBUGLOG(SPDK_LOG_NVME, "Prepare to destruct SSD: %s\n", ctrlr->trid.traddr);
  
  	ctrlr->is_destructed = true;
  
  	spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  	nvme_transport_admin_qpair_abort_aers(ctrlr->adminq);
  
  	TAILQ_FOREACH_SAFE(qpair, &ctrlr->active_io_qpairs, tailq, tmp) {
  		spdk_nvme_ctrlr_free_io_qpair(qpair);
  	}
  
  	nvme_ctrlr_free_doorbell_buffer(ctrlr);
  
  	if (ctrlr->opts.no_shn_notification) {
  		SPDK_INFOLOG(SPDK_LOG_NVME, "Disable SSD: %s without shutdown notification\n",
  			     ctrlr->trid.traddr);
  		nvme_ctrlr_disable(ctrlr);
  	} else {
  		nvme_ctrlr_shutdown(ctrlr);
  	}
  
  	nvme_ctrlr_destruct_namespaces(ctrlr);
  
  	spdk_bit_array_free(&ctrlr->free_io_qids);
  
  	nvme_transport_ctrlr_destruct(ctrlr);
  }
  
  int
  nvme_ctrlr_submit_admin_request(struct spdk_nvme_ctrlr *ctrlr,
  				struct nvme_request *req)
  {
  	return nvme_qpair_submit_request(ctrlr->adminq, req);
  }
  
  static void
  nvme_keep_alive_completion(void *cb_ctx, const struct spdk_nvme_cpl *cpl)
  {
  	/* Do nothing */
  }
  
  /*
   * Check if we need to send a Keep Alive command.
   * Caller must hold ctrlr->ctrlr_lock.
   */
  static void
  nvme_ctrlr_keep_alive(struct spdk_nvme_ctrlr *ctrlr)
  {
  	uint64_t now;
  	struct nvme_request *req;
  	struct spdk_nvme_cmd *cmd;
  	int rc;
  
  	now = spdk_get_ticks();
  	if (now < ctrlr->next_keep_alive_tick) {
  		return;
  	}
  
  	req = nvme_allocate_request_null(ctrlr->adminq, nvme_keep_alive_completion, NULL);
  	if (req == NULL) {
  		return;
  	}
  
  	cmd = &req->cmd;
  	cmd->opc = SPDK_NVME_OPC_KEEP_ALIVE;
  
  	rc = nvme_ctrlr_submit_admin_request(ctrlr, req);
  	if (rc != 0) {
  		SPDK_ERRLOG("Submitting Keep Alive failed\n");
  	}
  
  	ctrlr->next_keep_alive_tick = now + ctrlr->keep_alive_interval_ticks;
  }
  
  int32_t
  spdk_nvme_ctrlr_process_admin_completions(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int32_t num_completions;
  	int32_t rc;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	if (ctrlr->keep_alive_interval_ticks) {
  		nvme_ctrlr_keep_alive(ctrlr);
  	}
  
  	rc = spdk_nvme_io_msg_process(ctrlr);
  	if (rc < 0) {
  		nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  		return rc;
  	}
  	num_completions = rc;
  
  	rc = spdk_nvme_qpair_process_completions(ctrlr->adminq, 0);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	if (rc < 0) {
  		num_completions = rc;
  	} else {
  		num_completions += rc;
  	}
  
  	return num_completions;
  }
  
  const struct spdk_nvme_ctrlr_data *
  spdk_nvme_ctrlr_get_data(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return &ctrlr->cdata;
  }
  
  union spdk_nvme_csts_register spdk_nvme_ctrlr_get_regs_csts(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_csts_register csts;
  
  	if (nvme_ctrlr_get_csts(ctrlr, &csts)) {
  		csts.raw = 0xFFFFFFFFu;
  	}
  	return csts;
  }
  
  union spdk_nvme_cap_register spdk_nvme_ctrlr_get_regs_cap(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->cap;
  }
  
  union spdk_nvme_vs_register spdk_nvme_ctrlr_get_regs_vs(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->vs;
  }
  
  union spdk_nvme_cmbsz_register spdk_nvme_ctrlr_get_regs_cmbsz(struct spdk_nvme_ctrlr *ctrlr)
  {
  	union spdk_nvme_cmbsz_register cmbsz;
  
  	if (nvme_ctrlr_get_cmbsz(ctrlr, &cmbsz)) {
  		cmbsz.raw = 0;
  	}
  
  	return cmbsz;
  }
  
  uint32_t
  spdk_nvme_ctrlr_get_num_ns(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->num_ns;
  }
  
  static int32_t
  spdk_nvme_ctrlr_active_ns_idx(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid)
  {
  	int32_t result = -1;
  
  	if (ctrlr->active_ns_list == NULL || nsid == 0 || nsid > ctrlr->num_ns) {
  		return result;
  	}
  
  	int32_t lower = 0;
  	int32_t upper = ctrlr->num_ns - 1;
  	int32_t mid;
  
  	while (lower <= upper) {
  		mid = lower + (upper - lower) / 2;
  		if (ctrlr->active_ns_list[mid] == nsid) {
  			result = mid;
  			break;
  		} else {
  			if (ctrlr->active_ns_list[mid] != 0 && ctrlr->active_ns_list[mid] < nsid) {
  				lower = mid + 1;
  			} else {
  				upper = mid - 1;
  			}
  
  		}
  	}
  
  	return result;
  }
  
  bool
  spdk_nvme_ctrlr_is_active_ns(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid)
  {
  	return spdk_nvme_ctrlr_active_ns_idx(ctrlr, nsid) != -1;
  }
  
  uint32_t
  spdk_nvme_ctrlr_get_first_active_ns(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->active_ns_list ? ctrlr->active_ns_list[0] : 0;
  }
  
  uint32_t
  spdk_nvme_ctrlr_get_next_active_ns(struct spdk_nvme_ctrlr *ctrlr, uint32_t prev_nsid)
  {
  	int32_t nsid_idx = spdk_nvme_ctrlr_active_ns_idx(ctrlr, prev_nsid);
  	if (ctrlr->active_ns_list && nsid_idx >= 0 && (uint32_t)nsid_idx < ctrlr->num_ns - 1) {
  		return ctrlr->active_ns_list[nsid_idx + 1];
  	}
  	return 0;
  }
  
  struct spdk_nvme_ns *
  spdk_nvme_ctrlr_get_ns(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid)
  {
  	if (nsid < 1 || nsid > ctrlr->num_ns) {
  		return NULL;
  	}
  
  	return &ctrlr->ns[nsid - 1];
  }
  
  struct spdk_pci_device *
  spdk_nvme_ctrlr_get_pci_device(struct spdk_nvme_ctrlr *ctrlr)
  {
  	if (ctrlr == NULL) {
  		return NULL;
  	}
  
  	if (ctrlr->trid.trtype != SPDK_NVME_TRANSPORT_PCIE) {
  		return NULL;
  	}
  
  	return nvme_ctrlr_proc_get_devhandle(ctrlr);
  }
  
  uint32_t
  spdk_nvme_ctrlr_get_max_xfer_size(const struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->max_xfer_size;
  }
  
  void
  spdk_nvme_ctrlr_register_aer_callback(struct spdk_nvme_ctrlr *ctrlr,
  				      spdk_nvme_aer_cb aer_cb_fn,
  				      void *aer_cb_arg)
  {
  	struct spdk_nvme_ctrlr_process *active_proc;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc) {
  		active_proc->aer_cb_fn = aer_cb_fn;
  		active_proc->aer_cb_arg = aer_cb_arg;
  	}
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  void
  spdk_nvme_ctrlr_register_timeout_callback(struct spdk_nvme_ctrlr *ctrlr,
  		uint64_t timeout_us, spdk_nvme_timeout_cb cb_fn, void *cb_arg)
  {
  	struct spdk_nvme_ctrlr_process	*active_proc;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  
  	active_proc = spdk_nvme_ctrlr_get_current_process(ctrlr);
  	if (active_proc) {
  		active_proc->timeout_ticks = timeout_us * spdk_get_ticks_hz() / 1000000ULL;
  		active_proc->timeout_cb_fn = cb_fn;
  		active_proc->timeout_cb_arg = cb_arg;
  	}
  
  	ctrlr->timeout_enabled = true;
  
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  bool
  spdk_nvme_ctrlr_is_log_page_supported(struct spdk_nvme_ctrlr *ctrlr, uint8_t log_page)
  {
  	/* No bounds check necessary, since log_page is uint8_t and log_page_supported has 256 entries */
  	SPDK_STATIC_ASSERT(sizeof(ctrlr->log_page_supported) == 256, "log_page_supported size mismatch");
  	return ctrlr->log_page_supported[log_page];
  }
  
  bool
  spdk_nvme_ctrlr_is_feature_supported(struct spdk_nvme_ctrlr *ctrlr, uint8_t feature_code)
  {
  	/* No bounds check necessary, since feature_code is uint8_t and feature_supported has 256 entries */
  	SPDK_STATIC_ASSERT(sizeof(ctrlr->feature_supported) == 256, "feature_supported size mismatch");
  	return ctrlr->feature_supported[feature_code];
  }
  
  int
  spdk_nvme_ctrlr_attach_ns(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid,
  			  struct spdk_nvme_ctrlr_list *payload)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  	struct spdk_nvme_ns			*ns;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	res = nvme_ctrlr_cmd_attach_ns(ctrlr, nsid, payload,
  				       nvme_completion_poll_cb, status);
  	if (res) {
  		free(status);
  		return res;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_attach_ns failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return -ENXIO;
  	}
  	free(status);
  
  	res = nvme_ctrlr_identify_active_ns(ctrlr);
  	if (res) {
  		return res;
  	}
  
  	ns = &ctrlr->ns[nsid - 1];
  	return nvme_ns_construct(ns, nsid, ctrlr);
  }
  
  int
  spdk_nvme_ctrlr_detach_ns(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid,
  			  struct spdk_nvme_ctrlr_list *payload)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  	struct spdk_nvme_ns			*ns;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	res = nvme_ctrlr_cmd_detach_ns(ctrlr, nsid, payload,
  				       nvme_completion_poll_cb, status);
  	if (res) {
  		free(status);
  		return res;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_detach_ns failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return -ENXIO;
  	}
  	free(status);
  
  	res = nvme_ctrlr_identify_active_ns(ctrlr);
  	if (res) {
  		return res;
  	}
  
  	ns = &ctrlr->ns[nsid - 1];
  	/* Inactive NS */
  	nvme_ns_destruct(ns);
  
  	return 0;
  }
  
  uint32_t
  spdk_nvme_ctrlr_create_ns(struct spdk_nvme_ctrlr *ctrlr, struct spdk_nvme_ns_data *payload)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  	uint32_t				nsid;
  	struct spdk_nvme_ns			*ns;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return 0;
  	}
  
  	res = nvme_ctrlr_cmd_create_ns(ctrlr, payload, nvme_completion_poll_cb, status);
  	if (res) {
  		free(status);
  		return 0;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_create_ns failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return 0;
  	}
  
  	nsid = status->cpl.cdw0;
  	ns = &ctrlr->ns[nsid - 1];
  	free(status);
  	/* Inactive NS */
  	res = nvme_ns_construct(ns, nsid, ctrlr);
  	if (res) {
  		return 0;
  	}
  
  	/* Return the namespace ID that was created */
  	return nsid;
  }
  
  int
  spdk_nvme_ctrlr_delete_ns(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  	struct spdk_nvme_ns			*ns;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	res = nvme_ctrlr_cmd_delete_ns(ctrlr, nsid, nvme_completion_poll_cb, status);
  	if (res) {
  		free(status);
  		return res;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_delete_ns failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return -ENXIO;
  	}
  	free(status);
  
  	res = nvme_ctrlr_identify_active_ns(ctrlr);
  	if (res) {
  		return res;
  	}
  
  	ns = &ctrlr->ns[nsid - 1];
  	nvme_ns_destruct(ns);
  
  	return 0;
  }
  
  int
  spdk_nvme_ctrlr_format(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid,
  		       struct spdk_nvme_format *format)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	res = nvme_ctrlr_cmd_format(ctrlr, nsid, format, nvme_completion_poll_cb,
  				    status);
  	if (res) {
  		free(status);
  		return res;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_format failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return -ENXIO;
  	}
  	free(status);
  
  	return spdk_nvme_ctrlr_reset(ctrlr);
  }
  
  int
  spdk_nvme_ctrlr_update_firmware(struct spdk_nvme_ctrlr *ctrlr, void *payload, uint32_t size,
  				int slot, enum spdk_nvme_fw_commit_action commit_action, struct spdk_nvme_status *completion_status)
  {
  	struct spdk_nvme_fw_commit		fw_commit;
  	struct nvme_completion_poll_status	*status;
  	int					res;
  	unsigned int				size_remaining;
  	unsigned int				offset;
  	unsigned int				transfer;
  	void					*p;
  
  	if (!completion_status) {
  		return -EINVAL;
  	}
  	memset(completion_status, 0, sizeof(struct spdk_nvme_status));
  	if (size % 4) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_update_firmware invalid size!\n");
  		return -1;
  	}
  
  	/* Current support only for SPDK_NVME_FW_COMMIT_REPLACE_IMG
  	 * and SPDK_NVME_FW_COMMIT_REPLACE_AND_ENABLE_IMG
  	 */
  	if ((commit_action != SPDK_NVME_FW_COMMIT_REPLACE_IMG) &&
  	    (commit_action != SPDK_NVME_FW_COMMIT_REPLACE_AND_ENABLE_IMG)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_update_firmware invalid command!\n");
  		return -1;
  	}
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	/* Firmware download */
  	size_remaining = size;
  	offset = 0;
  	p = payload;
  
  	while (size_remaining > 0) {
  		transfer = spdk_min(size_remaining, ctrlr->min_page_size);
  
  		memset(status, 0, sizeof(*status));
  		res = nvme_ctrlr_cmd_fw_image_download(ctrlr, transfer, offset, p,
  						       nvme_completion_poll_cb,
  						       status);
  		if (res) {
  			free(status);
  			return res;
  		}
  
  		if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  			SPDK_ERRLOG("spdk_nvme_ctrlr_fw_image_download failed!\n");
  			if (!status->timed_out) {
  				free(status);
  			}
  			return -ENXIO;
  		}
  		p += transfer;
  		offset += transfer;
  		size_remaining -= transfer;
  	}
  
  	/* Firmware commit */
  	memset(&fw_commit, 0, sizeof(struct spdk_nvme_fw_commit));
  	fw_commit.fs = slot;
  	fw_commit.ca = commit_action;
  
  	memset(status, 0, sizeof(*status));
  	res = nvme_ctrlr_cmd_fw_commit(ctrlr, &fw_commit, nvme_completion_poll_cb,
  				       status);
  	if (res) {
  		free(status);
  		return res;
  	}
  
  	res = spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock);
  
  	memcpy(completion_status, &status->cpl.status, sizeof(struct spdk_nvme_status));
  
  	if (!status->timed_out) {
  		free(status);
  	}
  
  	if (res) {
  		if (completion_status->sct != SPDK_NVME_SCT_COMMAND_SPECIFIC ||
  		    completion_status->sc != SPDK_NVME_SC_FIRMWARE_REQ_NVM_RESET) {
  			if (completion_status->sct == SPDK_NVME_SCT_COMMAND_SPECIFIC  &&
  			    completion_status->sc == SPDK_NVME_SC_FIRMWARE_REQ_CONVENTIONAL_RESET) {
  				SPDK_NOTICELOG("firmware activation requires conventional reset to be performed. !\n");
  			} else {
  				SPDK_ERRLOG("nvme_ctrlr_cmd_fw_commit failed!\n");
  			}
  			return -ENXIO;
  		}
  	}
  
  	return spdk_nvme_ctrlr_reset(ctrlr);
  }
  
  int
  spdk_nvme_ctrlr_reserve_cmb(struct spdk_nvme_ctrlr *ctrlr)
  {
  	int rc, size;
  	union spdk_nvme_cmbsz_register cmbsz;
  
  	cmbsz = spdk_nvme_ctrlr_get_regs_cmbsz(ctrlr);
  
  	if (cmbsz.bits.rds == 0 || cmbsz.bits.wds == 0) {
  		return -ENOTSUP;
  	}
  
  	size = cmbsz.bits.sz * (0x1000 << (cmbsz.bits.szu * 4));
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	rc = nvme_transport_ctrlr_reserve_cmb(ctrlr);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	if (rc < 0) {
  		return rc;
  	}
  
  	return size;
  }
  
  void *
  spdk_nvme_ctrlr_map_cmb(struct spdk_nvme_ctrlr *ctrlr, size_t *size)
  {
  	void *buf;
  
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	buf = nvme_transport_ctrlr_map_cmb(ctrlr, size);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  
  	return buf;
  }
  
  void
  spdk_nvme_ctrlr_unmap_cmb(struct spdk_nvme_ctrlr *ctrlr)
  {
  	nvme_robust_mutex_lock(&ctrlr->ctrlr_lock);
  	nvme_transport_ctrlr_unmap_cmb(ctrlr);
  	nvme_robust_mutex_unlock(&ctrlr->ctrlr_lock);
  }
  
  bool
  spdk_nvme_ctrlr_is_discovery(struct spdk_nvme_ctrlr *ctrlr)
  {
  	assert(ctrlr);
  
  	return !strncmp(ctrlr->trid.subnqn, SPDK_NVMF_DISCOVERY_NQN,
  			strlen(SPDK_NVMF_DISCOVERY_NQN));
  }
  
  int
  spdk_nvme_ctrlr_security_receive(struct spdk_nvme_ctrlr *ctrlr, uint8_t secp,
  				 uint16_t spsp, uint8_t nssf, void *payload, size_t size)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	res = spdk_nvme_ctrlr_cmd_security_receive(ctrlr, secp, spsp, nssf, payload, size,
  			nvme_completion_poll_cb, status);
  	if (res) {
  		free(status);
  		return res;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_cmd_security_receive failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return -ENXIO;
  	}
  	free(status);
  
  	return 0;
  }
  
  int
  spdk_nvme_ctrlr_security_send(struct spdk_nvme_ctrlr *ctrlr, uint8_t secp,
  			      uint16_t spsp, uint8_t nssf, void *payload, size_t size)
  {
  	struct nvme_completion_poll_status	*status;
  	int					res;
  
  	status = calloc(1, sizeof(*status));
  	if (!status) {
  		SPDK_ERRLOG("Failed to allocate status tracker\n");
  		return -ENOMEM;
  	}
  
  	res = spdk_nvme_ctrlr_cmd_security_send(ctrlr, secp, spsp, nssf, payload, size,
  						nvme_completion_poll_cb,
  						status);
  	if (res) {
  		free(status);
  		return res;
  	}
  	if (spdk_nvme_wait_for_completion_robust_lock(ctrlr->adminq, status, &ctrlr->ctrlr_lock)) {
  		SPDK_ERRLOG("spdk_nvme_ctrlr_cmd_security_send failed!\n");
  		if (!status->timed_out) {
  			free(status);
  		}
  		return -ENXIO;
  	}
  
  	free(status);
  
  	return 0;
  }
  
  uint64_t
  spdk_nvme_ctrlr_get_flags(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return ctrlr->flags;
  }
  
  const struct spdk_nvme_transport_id *
  spdk_nvme_ctrlr_get_transport_id(struct spdk_nvme_ctrlr *ctrlr)
  {
  	return &ctrlr->trid;
  }
  
  /* FIXME need to specify max number of iovs */
  int
  spdk_nvme_map_prps(void *prv, struct spdk_nvme_cmd *cmd, struct iovec *iovs,
  		   uint32_t len, size_t mps,
  		   void *(*gpa_to_vva)(void *prv, uint64_t addr, uint64_t len))
  {
  	uint64_t prp1, prp2;
  	void *vva;
  	uint32_t i;
  	uint32_t residue_len, nents;
  	uint64_t *prp_list;
  	int iovcnt;
  
  	prp1 = cmd->dptr.prp.prp1;
  	prp2 = cmd->dptr.prp.prp2;
  
  	/* PRP1 may started with unaligned page address */
  	residue_len = mps - (prp1 % mps);
  	residue_len = spdk_min(len, residue_len);
  
  	vva = gpa_to_vva(prv, prp1, residue_len);
  	if (spdk_unlikely(vva == NULL)) {
  		SPDK_ERRLOG("GPA to VVA failed\n");
  		return -1;
  	}
  	iovs[0].iov_base = vva;
  	iovs[0].iov_len = residue_len;
  	len -= residue_len;
  
  	if (len) {
  		if (spdk_unlikely(prp2 == 0)) {
  			SPDK_ERRLOG("no PRP2, %d remaining\n", len);
  			return -1;
  		}
  
  		if (len <= mps) {
  			/* 2 PRP used */
  			iovcnt = 2;
  			vva = gpa_to_vva(prv, prp2, len);
  			if (spdk_unlikely(vva == NULL)) {
  				SPDK_ERRLOG("no VVA for %#lx, len%#x\n",
  					    prp2, len);
  				return -1;
  			}
  			iovs[1].iov_base = vva;
  			iovs[1].iov_len = len;
  		} else {
  			/* PRP list used */
  			nents = (len + mps - 1) / mps;
  			vva = gpa_to_vva(prv, prp2, nents * sizeof(*prp_list));
  			if (spdk_unlikely(vva == NULL)) {
  				SPDK_ERRLOG("no VVA for %#lx, nents=%#x\n",
  					    prp2, nents);
  				return -1;
  			}
  			prp_list = vva;
  			i = 0;
  			while (len != 0) {
  				residue_len = spdk_min(len, mps);
  				vva = gpa_to_vva(prv, prp_list[i], residue_len);
  				if (spdk_unlikely(vva == NULL)) {
  					SPDK_ERRLOG("no VVA for %#lx, residue_len=%#x\n",
  						    prp_list[i], residue_len);
  					return -1;
  				}
  				iovs[i + 1].iov_base = vva;
  				iovs[i + 1].iov_len = residue_len;
  				len -= residue_len;
  				i++;
  			}
  			iovcnt = i + 1;
  		}
  	} else {
  		/* 1 PRP used */
  		iovcnt = 1;
  	}
  
  	return iovcnt;
  }
  