[PATCH v6 13/42] nvme: add support for the asynchronous event request command

[Klaus Jensen <its@irrelevant.dk>]

From: Klaus Jensen <k.jensen@samsung.com>

Required for compliance with NVMe revision 1.2.1. See NVM Express 1.2.1,
Section 5.2 ("Asynchronous Event Request command").

Mostly imported from Keith's qemu-nvme tree. Modified with a max number
of queued events (controllable with the aer_max_queued device
parameter). The spec states that the controller *should* retain
events, so we do best effort here.

Signed-off-by: Klaus Jensen <klaus.jensen@cnexlabs.com>
Acked-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 hw/block/nvme.c       | 178 ++++++++++++++++++++++++++++++++++++++++--
 hw/block/nvme.h       |  14 +++-
 hw/block/trace-events |   9 +++
 include/block/nvme.h  |   8 +-
 4 files changed, 199 insertions(+), 10 deletions(-)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 83ff3fbfb463..ff8975cd6667 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -325,6 +325,85 @@ static void nvme_enqueue_req_completion(NvmeCQueue *cq, NvmeRequest *req)
     timer_mod(cq->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 500);
 }
 
+static void nvme_process_aers(void *opaque)
+{
+    NvmeCtrl *n = opaque;
+    NvmeAsyncEvent *event, *next;
+
+    trace_nvme_dev_process_aers(n->aer_queued);
+
+    QTAILQ_FOREACH_SAFE(event, &n->aer_queue, entry, next) {
+        NvmeRequest *req;
+        NvmeAerResult *result;
+
+        /* can't post cqe if there is nothing to complete */
+        if (!n->outstanding_aers) {
+            trace_nvme_dev_no_outstanding_aers();
+            break;
+        }
+
+        /* ignore if masked (cqe posted, but event not cleared) */
+        if (n->aer_mask & (1 << event->result.event_type)) {
+            trace_nvme_dev_aer_masked(event->result.event_type, n->aer_mask);
+            continue;
+        }
+
+        QTAILQ_REMOVE(&n->aer_queue, event, entry);
+        n->aer_queued--;
+
+        n->aer_mask |= 1 << event->result.event_type;
+        n->outstanding_aers--;
+
+        req = n->aer_reqs[n->outstanding_aers];
+
+        result = (NvmeAerResult *) &req->cqe.result;
+        result->event_type = event->result.event_type;
+        result->event_info = event->result.event_info;
+        result->log_page = event->result.log_page;
+        g_free(event);
+
+        req->status = NVME_SUCCESS;
+
+        trace_nvme_dev_aer_post_cqe(result->event_type, result->event_info,
+                                    result->log_page);
+
+        nvme_enqueue_req_completion(&n->admin_cq, req);
+    }
+}
+
+static void nvme_enqueue_event(NvmeCtrl *n, uint8_t event_type,
+                               uint8_t event_info, uint8_t log_page)
+{
+    NvmeAsyncEvent *event;
+
+    trace_nvme_dev_enqueue_event(event_type, event_info, log_page);
+
+    if (n->aer_queued == n->params.aer_max_queued) {
+        trace_nvme_dev_enqueue_event_noqueue(n->aer_queued);
+        return;
+    }
+
+    event = g_new(NvmeAsyncEvent, 1);
+    event->result = (NvmeAerResult) {
+        .event_type = event_type,
+        .event_info = event_info,
+        .log_page   = log_page,
+    };
+
+    QTAILQ_INSERT_TAIL(&n->aer_queue, event, entry);
+    n->aer_queued++;
+
+    nvme_process_aers(n);
+}
+
+static void nvme_clear_events(NvmeCtrl *n, uint8_t event_type)
+{
+    n->aer_mask &= ~(1 << event_type);
+    if (!QTAILQ_EMPTY(&n->aer_queue)) {
+        nvme_process_aers(n);
+    }
+}
+
 static void nvme_rw_cb(void *opaque, int ret)
 {
     NvmeRequest *req = opaque;
@@ -569,8 +648,9 @@ static uint16_t nvme_create_sq(NvmeCtrl *n, NvmeCmd *cmd)
     return NVME_SUCCESS;
 }
 
-static uint16_t nvme_smart_info(NvmeCtrl *n, NvmeCmd *cmd, uint32_t buf_len,
-                                uint64_t off, NvmeRequest *req)
+static uint16_t nvme_smart_info(NvmeCtrl *n, NvmeCmd *cmd, uint8_t rae,
+                                uint32_t buf_len, uint64_t off,
+                                NvmeRequest *req)
 {
     uint64_t prp1 = le64_to_cpu(cmd->dptr.prp1);
     uint64_t prp2 = le64_to_cpu(cmd->dptr.prp2);
@@ -619,6 +699,10 @@ static uint16_t nvme_smart_info(NvmeCtrl *n, NvmeCmd *cmd, uint32_t buf_len,
     smart.power_on_hours[0] =
         cpu_to_le64((((current_ms - n->starttime_ms) / 1000) / 60) / 60);
 
+    if (!rae) {
+        nvme_clear_events(n, NVME_AER_TYPE_SMART);
+    }
+
     return nvme_dma_read_prp(n, (uint8_t *) &smart + off, trans_len, prp1,
                              prp2);
 }
@@ -643,14 +727,19 @@ static uint16_t nvme_fw_log_info(NvmeCtrl *n, NvmeCmd *cmd, uint32_t buf_len,
                              prp2);
 }
 
-static uint16_t nvme_error_info(NvmeCtrl *n, NvmeCmd *cmd, uint32_t buf_len,
-                                uint64_t off, NvmeRequest *req)
+static uint16_t nvme_error_info(NvmeCtrl *n, NvmeCmd *cmd, uint8_t rae,
+                                uint32_t buf_len, uint64_t off,
+                                NvmeRequest *req)
 {
     uint32_t trans_len;
     uint64_t prp1 = le64_to_cpu(cmd->dptr.prp1);
     uint64_t prp2 = le64_to_cpu(cmd->dptr.prp2);
     uint8_t errlog[64];
 
+    if (!rae) {
+        nvme_clear_events(n, NVME_AER_TYPE_ERROR);
+    }
+
     if (off > sizeof(errlog)) {
         return NVME_INVALID_FIELD | NVME_DNR;
     }
@@ -690,9 +779,9 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 
     switch (lid) {
     case NVME_LOG_ERROR_INFO:
-        return nvme_error_info(n, cmd, len, off, req);
+        return nvme_error_info(n, cmd, rae, len, off, req);
     case NVME_LOG_SMART_INFO:
-        return nvme_smart_info(n, cmd, len, off, req);
+        return nvme_smart_info(n, cmd, rae, len, off, req);
     case NVME_LOG_FW_SLOT_INFO:
         return nvme_fw_log_info(n, cmd, len, off, req);
     default:
@@ -969,6 +1058,9 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
         break;
     case NVME_TIMESTAMP:
         return nvme_get_feature_timestamp(n, cmd);
+    case NVME_ASYNCHRONOUS_EVENT_CONF:
+        result = cpu_to_le32(n->features.async_config);
+        break;
     default:
         trace_nvme_dev_err_invalid_getfeat(dw10);
         return NVME_INVALID_FIELD | NVME_DNR;
@@ -1018,6 +1110,14 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
             return NVME_INVALID_FIELD | NVME_DNR;
         }
 
+        if (((n->temperature > n->features.temp_thresh_hi) ||
+            (n->temperature < n->features.temp_thresh_low)) &&
+            NVME_AEC_SMART(n->features.async_config) & NVME_SMART_TEMPERATURE) {
+            nvme_enqueue_event(n, NVME_AER_TYPE_SMART,
+                               NVME_AER_INFO_SMART_TEMP_THRESH,
+                               NVME_LOG_SMART_INFO);
+        }
+
         break;
     case NVME_VOLATILE_WRITE_CACHE:
         blk_set_enable_write_cache(n->conf.blk, dw11 & 1);
@@ -1032,6 +1132,9 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
         break;
     case NVME_TIMESTAMP:
         return nvme_set_feature_timestamp(n, cmd);
+    case NVME_ASYNCHRONOUS_EVENT_CONF:
+        n->features.async_config = dw11;
+        break;
     default:
         trace_nvme_dev_err_invalid_setfeat(dw10);
         return NVME_INVALID_FIELD | NVME_DNR;
@@ -1039,6 +1142,25 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
     return NVME_SUCCESS;
 }
 
+static uint16_t nvme_aer(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
+{
+    trace_nvme_dev_aer(nvme_cid(req));
+
+    if (n->outstanding_aers > n->params.aerl) {
+        trace_nvme_dev_aer_aerl_exceeded();
+        return NVME_AER_LIMIT_EXCEEDED;
+    }
+
+    n->aer_reqs[n->outstanding_aers] = req;
+    n->outstanding_aers++;
+
+    if (!QTAILQ_EMPTY(&n->aer_queue)) {
+        nvme_process_aers(n);
+    }
+
+    return NVME_NO_COMPLETE;
+}
+
 static uint16_t nvme_admin_cmd(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
     switch (cmd->opcode) {
@@ -1060,6 +1182,8 @@ static uint16_t nvme_admin_cmd(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
         return nvme_set_feature(n, cmd, req);
     case NVME_ADM_CMD_GET_FEATURES:
         return nvme_get_feature(n, cmd, req);
+    case NVME_ADM_CMD_ASYNC_EV_REQ:
+        return nvme_aer(n, cmd, req);
     default:
         trace_nvme_dev_err_invalid_admin_opc(cmd->opcode);
         return NVME_INVALID_OPCODE | NVME_DNR;
@@ -1114,6 +1238,15 @@ static void nvme_clear_ctrl(NvmeCtrl *n)
         }
     }
 
+    while (!QTAILQ_EMPTY(&n->aer_queue)) {
+        NvmeAsyncEvent *event = QTAILQ_FIRST(&n->aer_queue);
+        QTAILQ_REMOVE(&n->aer_queue, event, entry);
+        g_free(event);
+    }
+
+    n->aer_queued = 0;
+    n->outstanding_aers = 0;
+
     blk_flush(n->conf.blk);
     n->bar.cc = 0;
 }
@@ -1210,6 +1343,8 @@ static int nvme_start_ctrl(NvmeCtrl *n)
 
     nvme_set_timestamp(n, 0ULL);
 
+    QTAILQ_INIT(&n->aer_queue);
+
     return 0;
 }
 
@@ -1402,6 +1537,13 @@ static void nvme_process_db(NvmeCtrl *n, hwaddr addr, int val)
                            "completion queue doorbell write"
                            " for nonexistent queue,"
                            " sqid=%"PRIu32", ignoring", qid);
+
+            if (n->outstanding_aers) {
+                nvme_enqueue_event(n, NVME_AER_TYPE_ERROR,
+                                   NVME_AER_INFO_ERR_INVALID_DB_REGISTER,
+                                   NVME_LOG_ERROR_INFO);
+            }
+
             return;
         }
 
@@ -1412,6 +1554,13 @@ static void nvme_process_db(NvmeCtrl *n, hwaddr addr, int val)
                            " beyond queue size, sqid=%"PRIu32","
                            " new_head=%"PRIu16", ignoring",
                            qid, new_head);
+
+            if (n->outstanding_aers) {
+                nvme_enqueue_event(n, NVME_AER_TYPE_ERROR,
+                                   NVME_AER_INFO_ERR_INVALID_DB_VALUE,
+                                   NVME_LOG_ERROR_INFO);
+            }
+
             return;
         }
 
@@ -1440,6 +1589,13 @@ static void nvme_process_db(NvmeCtrl *n, hwaddr addr, int val)
                            "submission queue doorbell write"
                            " for nonexistent queue,"
                            " sqid=%"PRIu32", ignoring", qid);
+
+            if (n->outstanding_aers) {
+                nvme_enqueue_event(n, NVME_AER_TYPE_ERROR,
+                                   NVME_AER_INFO_ERR_INVALID_DB_REGISTER,
+                                   NVME_LOG_ERROR_INFO);
+            }
+
             return;
         }
 
@@ -1450,6 +1606,13 @@ static void nvme_process_db(NvmeCtrl *n, hwaddr addr, int val)
                            " beyond queue size, sqid=%"PRIu32","
                            " new_tail=%"PRIu16", ignoring",
                            qid, new_tail);
+
+            if (n->outstanding_aers) {
+                nvme_enqueue_event(n, NVME_AER_TYPE_ERROR,
+                                   NVME_AER_INFO_ERR_INVALID_DB_VALUE,
+                                   NVME_LOG_ERROR_INFO);
+            }
+
             return;
         }
 
@@ -1553,6 +1716,7 @@ static void nvme_init_state(NvmeCtrl *n)
     n->temperature = NVME_TEMPERATURE;
     n->features.temp_thresh_hi = NVME_TEMPERATURE_WARNING;
     n->starttime_ms = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
+    n->aer_reqs = g_new0(NvmeRequest *, n->params.aerl + 1);
 }
 
 static void nvme_init_cmb(NvmeCtrl *n, PCIDevice *pci_dev)
@@ -1628,6 +1792,7 @@ static void nvme_init_ctrl(NvmeCtrl *n)
      * inconsequential.
      */
     id->acl = 3;
+    id->aerl = n->params.aerl;
     id->frmw = 7 << 1;
     id->lpa = 1 << 2;
 
@@ -1713,6 +1878,7 @@ static void nvme_exit(PCIDevice *pci_dev)
     g_free(n->namespaces);
     g_free(n->cq);
     g_free(n->sq);
+    g_free(n->aer_reqs);
 
     if (n->params.cmb_size_mb) {
         g_free(n->cmbuf);
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index ebeee2edc4f4..b709a8bb8d40 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -7,17 +7,21 @@
     DEFINE_PROP_STRING("serial", _state, _props.serial), \
     DEFINE_PROP_UINT32("cmb_size_mb", _state, _props.cmb_size_mb, 0), \
     DEFINE_PROP_UINT32("num_queues", _state, _props.num_queues, 0), \
-    DEFINE_PROP_UINT32("max_ioqpairs", _state, _props.max_ioqpairs, 64)
+    DEFINE_PROP_UINT32("max_ioqpairs", _state, _props.max_ioqpairs, 64), \
+    DEFINE_PROP_UINT8("aerl", _state, _props.aerl, 3), \
+    DEFINE_PROP_UINT32("aer_max_queued", _state, _props.aer_max_queued, 64)
 
 typedef struct NvmeParams {
     char     *serial;
     uint32_t num_queues;
     uint32_t max_ioqpairs;
     uint32_t cmb_size_mb;
+    uint8_t  aerl;
+    uint32_t aer_max_queued;
 } NvmeParams;
 
 typedef struct NvmeAsyncEvent {
-    QSIMPLEQ_ENTRY(NvmeAsyncEvent) entry;
+    QTAILQ_ENTRY(NvmeAsyncEvent) entry;
     NvmeAerResult result;
 } NvmeAsyncEvent;
 
@@ -104,6 +108,7 @@ typedef struct NvmeCtrl {
     uint32_t    num_namespaces;
     uint32_t    max_q_ents;
     uint64_t    ns_size;
+    uint8_t     outstanding_aers;
     uint8_t     *cmbuf;
     uint64_t    irq_status;
     uint64_t    host_timestamp;                 /* Timestamp sent by the host */
@@ -111,6 +116,11 @@ typedef struct NvmeCtrl {
     uint16_t    temperature;
     uint64_t    starttime_ms;
 
+    uint8_t     aer_mask;
+    NvmeRequest **aer_reqs;
+    QTAILQ_HEAD(, NvmeAsyncEvent) aer_queue;
+    int         aer_queued;
+
     NvmeNamespace   *namespaces;
     NvmeSQueue      **sq;
     NvmeCQueue      **cq;
diff --git a/hw/block/trace-events b/hw/block/trace-events
index 7da088479f39..3952c36774cf 100644
--- a/hw/block/trace-events
+++ b/hw/block/trace-events
@@ -47,6 +47,15 @@ nvme_dev_setfeat_numq(int reqcq, int reqsq, int gotcq, int gotsq) "requested cq_
 nvme_dev_setfeat_timestamp(uint64_t ts) "set feature timestamp = 0x%"PRIx64""
 nvme_dev_getfeat_timestamp(uint64_t ts) "get feature timestamp = 0x%"PRIx64""
 nvme_dev_get_log(uint16_t cid, uint8_t lid, uint8_t rae, uint32_t len, uint64_t off) "cid %"PRIu16" lid 0x%"PRIx8" rae 0x%"PRIx8" len %"PRIu32" off %"PRIu64""
+nvme_dev_process_aers(int queued) "queued %d"
+nvme_dev_aer(uint16_t cid) "cid %"PRIu16""
+nvme_dev_aer_aerl_exceeded(void) "aerl exceeded"
+nvme_dev_aer_masked(uint8_t type, uint8_t mask) "type 0x%"PRIx8" mask 0x%"PRIx8""
+nvme_dev_aer_post_cqe(uint8_t typ, uint8_t info, uint8_t log_page) "type 0x%"PRIx8" info 0x%"PRIx8" lid 0x%"PRIx8""
+nvme_dev_enqueue_event(uint8_t typ, uint8_t info, uint8_t log_page) "type 0x%"PRIx8" info 0x%"PRIx8" lid 0x%"PRIx8""
+nvme_dev_enqueue_event_noqueue(int queued) "queued %d"
+nvme_dev_enqueue_event_masked(uint8_t typ) "type 0x%"PRIx8""
+nvme_dev_no_outstanding_aers(void) "ignoring event; no outstanding AERs"
 nvme_dev_mmio_intm_set(uint64_t data, uint64_t new_mask) "wrote MMIO, interrupt mask set, data=0x%"PRIx64", new_mask=0x%"PRIx64""
 nvme_dev_mmio_intm_clr(uint64_t data, uint64_t new_mask) "wrote MMIO, interrupt mask clr, data=0x%"PRIx64", new_mask=0x%"PRIx64""
 nvme_dev_mmio_cfg(uint64_t data) "wrote MMIO, config controller config=0x%"PRIx64""
diff --git a/include/block/nvme.h b/include/block/nvme.h
index 91fc4738a3e0..f2a8b07c0f2f 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -425,8 +425,8 @@ enum NvmeAsyncEventRequest {
     NVME_AER_TYPE_SMART                     = 1,
     NVME_AER_TYPE_IO_SPECIFIC               = 6,
     NVME_AER_TYPE_VENDOR_SPECIFIC           = 7,
-    NVME_AER_INFO_ERR_INVALID_SQ            = 0,
-    NVME_AER_INFO_ERR_INVALID_DB            = 1,
+    NVME_AER_INFO_ERR_INVALID_DB_REGISTER   = 0,
+    NVME_AER_INFO_ERR_INVALID_DB_VALUE      = 1,
     NVME_AER_INFO_ERR_DIAG_FAIL             = 2,
     NVME_AER_INFO_ERR_PERS_INTERNAL_ERR     = 3,
     NVME_AER_INFO_ERR_TRANS_INTERNAL_ERR    = 4,
@@ -717,6 +717,10 @@ typedef struct NvmeFeatureVal {
 #define NVME_TEMP_TMPSEL(temp) ((temp >> 16) & 0xf)
 #define NVME_TEMP_TMPTH(temp)  ((temp >>  0) & 0xffff)
 
+#define NVME_AEC_SMART(aec)         (aec & 0xff)
+#define NVME_AEC_NS_ATTR(aec)       ((aec >> 8) & 0x1)
+#define NVME_AEC_FW_ACTIVATION(aec) ((aec >> 9) & 0x1)
+
 enum NvmeFeatureIds {
     NVME_ARBITRATION                = 0x1,
     NVME_POWER_MANAGEMENT           = 0x2,
-- 
2.25.1