From 2868353a572eea5b59bc04596d67fec1828c175b Mon Sep 17 00:00:00 2001
From: Jim Harris <jimharris@FreeBSD.org>
Date: Tue, 26 Mar 2013 21:05:15 +0000
Subject: [PATCH] When an asynchronous event request is completed,
 automatically fetch the specified log page.

This satisfies the spec condition that future async events of the same type
will not be sent until the associated log page is fetched.

Sponsored by:	Intel
Reviewed by:	carl
---
 sys/dev/nvme/nvme_ctrlr.c   | 88 ++++++++++++++++++++++++++++++++-----
 sys/dev/nvme/nvme_private.h |  6 +++
 2 files changed, 84 insertions(+), 10 deletions(-)

diff --git a/sys/dev/nvme/nvme_ctrlr.c b/sys/dev/nvme/nvme_ctrlr.c
index 345be9ca8c7..d4a95742d13 100644
--- a/sys/dev/nvme/nvme_ctrlr.c
+++ b/sys/dev/nvme/nvme_ctrlr.c
@@ -557,10 +557,65 @@ nvme_ctrlr_construct_namespaces(struct nvme_controller *ctrlr)
 	return (0);
 }
 
+static boolean_t
+is_log_page_id_valid(uint8_t page_id)
+{
+
+	switch (page_id) {
+	case NVME_LOG_ERROR:
+	case NVME_LOG_HEALTH_INFORMATION:
+	case NVME_LOG_FIRMWARE_SLOT:
+		return (TRUE);
+	}
+
+	return (FALSE);
+}
+
+static uint32_t
+nvme_ctrlr_get_log_page_size(struct nvme_controller *ctrlr, uint8_t page_id)
+{
+	uint32_t	log_page_size;
+
+	switch (page_id) {
+	case NVME_LOG_ERROR:
+		log_page_size = min(
+		    sizeof(struct nvme_error_information_entry) *
+		    ctrlr->cdata.elpe,
+		    NVME_MAX_AER_LOG_SIZE);
+		break;
+	case NVME_LOG_HEALTH_INFORMATION:
+		log_page_size = sizeof(struct nvme_health_information_page);
+		break;
+	case NVME_LOG_FIRMWARE_SLOT:
+		log_page_size = sizeof(struct nvme_firmware_page);
+		break;
+	default:
+		log_page_size = 0;
+		break;
+	}
+
+	return (log_page_size);
+}
+
+static void
+nvme_ctrlr_async_event_log_page_cb(void *arg, const struct nvme_completion *cpl)
+{
+	struct nvme_async_event_request	*aer = arg;
+
+	nvme_notify_async_consumers(aer->ctrlr, &aer->cpl);
+
+	/*
+	 * Repost another asynchronous event request to replace the one
+	 *  that just completed.
+	 */
+	nvme_ctrlr_construct_and_submit_aer(aer->ctrlr, aer);
+}
+
 static void
 nvme_ctrlr_async_event_cb(void *arg, const struct nvme_completion *cpl)
 {
-	struct nvme_async_event_request *aer = arg;
+	struct nvme_async_event_request	*aer = arg;
+	uint8_t				log_page_id;
 
 	if (cpl->status.sc == NVME_SC_ABORTED_SQ_DELETION) {
 		/*
@@ -572,16 +627,29 @@ nvme_ctrlr_async_event_cb(void *arg, const struct nvme_completion *cpl)
 		return;
 	}
 
-	nvme_notify_async_consumers(aer->ctrlr, cpl);
-
-	/* TODO: decode async event type based on status */
-
-	/*
-	 * Repost another asynchronous event request to replace the one that
-	 *  just completed.
-	 */
 	printf("Asynchronous event occurred.\n");
-	nvme_ctrlr_construct_and_submit_aer(aer->ctrlr, aer);
+
+	/* Associated log page is in bits 23:16 of completion entry dw0. */
+	log_page_id = (cpl->cdw0 & 0xFF0000) >> 16;
+
+	if (is_log_page_id_valid(log_page_id)) {
+		aer->log_page_size = nvme_ctrlr_get_log_page_size(aer->ctrlr,
+		    log_page_id);
+		memcpy(&aer->cpl, cpl, sizeof(*cpl));
+		nvme_ctrlr_cmd_get_log_page(aer->ctrlr, log_page_id,
+		    NVME_GLOBAL_NAMESPACE_TAG, aer->log_page_buffer,
+		    aer->log_page_size, nvme_ctrlr_async_event_log_page_cb,
+		    aer);
+		/* Wait to notify consumers until after log page is fetched. */
+	} else {
+		nvme_notify_async_consumers(aer->ctrlr, cpl);
+
+		/*
+		 * Repost another asynchronous event request to replace the one
+		 *  that just completed.
+		 */
+		nvme_ctrlr_construct_and_submit_aer(aer->ctrlr, aer);
+	}
 }
 
 static void
diff --git a/sys/dev/nvme/nvme_private.h b/sys/dev/nvme/nvme_private.h
index 624ae11dc9f..53d403e5037 100644
--- a/sys/dev/nvme/nvme_private.h
+++ b/sys/dev/nvme/nvme_private.h
@@ -104,6 +104,9 @@ MALLOC_DECLARE(M_NVME);
 #define NVME_MIN_TIMEOUT_PERIOD		(5)
 #define NVME_MAX_TIMEOUT_PERIOD		(120)
 
+/* Maximum log page size to fetch for AERs. */
+#define NVME_MAX_AER_LOG_SIZE		(4096)
+
 #ifndef CACHE_LINE_SIZE
 #define CACHE_LINE_SIZE		(64)
 #endif
@@ -126,6 +129,9 @@ struct nvme_async_event_request {
 
 	struct nvme_controller		*ctrlr;
 	struct nvme_request		*req;
+	struct nvme_completion		cpl;
+	uint32_t			log_page_size;
+	uint8_t				log_page_buffer[NVME_MAX_AER_LOG_SIZE];
 };
 
 struct nvme_tracker {