[Qemu-devel] [Qemu-block][PATCH] qemu-block: add support HMB with feature commands.

[Minwoo Im <minwoo.im.dev@gmail.com>]

Add support HMB(Host Memory Block) with feature commands(Get Feature, Set Feature).
nvme-4.14 tree supports HMB features.
This patch will make nvme controller to return 32MiB preferred size of HMB to host via identify command.
Set Feature, Get Feature implemented for HMB.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
---
 hw/block/nvme.c | 35 +++++++++++++++++++++++++++++++++++
 hw/block/nvme.h | 21 ++++++++++++++++++++-
 2 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 6071dc1..d351781 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -605,6 +605,23 @@ static uint16_t nvme_identify(NvmeCtrl *n, NvmeCmd *cmd)
     }
 }
 
+static uint32_t nvme_get_feature_hmb(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    uint32_t result = n->hmb_flag.flag;
+    uint64_t prp1 = le64_to_cpu(cmd->prp1);
+    uint64_t prp2 = le64_to_cpu(cmd->prp2);
+    NvmeHmbAttr attr = {0, };
+
+    attr.hsize = cpu_to_le32(n->hmb_attr.hsize);
+    attr.hmdlal = cpu_to_le32(n->hmb_attr.hmdlal);
+    attr.hmdlau = cpu_to_le32(n->hmb_attr.hmdlau);
+    attr.hmdlec = cpu_to_le32(n->hmb_attr.hmdlec);
+
+    nvme_dma_read_prp(n, (uint8_t *)&attr, sizeof(attr), prp1, prp2);
+
+    return result;
+}
+
 static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
     uint32_t dw10 = le32_to_cpu(cmd->cdw10);
@@ -617,6 +634,9 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
     case NVME_NUMBER_OF_QUEUES:
         result = cpu_to_le32((n->num_queues - 1) | ((n->num_queues - 1) << 16));
         break;
+    case NVME_HOST_MEMORY_BUFFER:
+        result = nvme_get_feature_hmb(n, cmd);
+        break;
     default:
         return NVME_INVALID_FIELD | NVME_DNR;
     }
@@ -625,6 +645,16 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
     return NVME_SUCCESS;
 }
 
+static void nvme_set_feature_hmb(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    n->hmb_flag.flag = le32_to_cpu(cmd->cdw11);
+
+    n->hmb_attr.hsize = le32_to_cpu(cmd->cdw12);
+    n->hmb_attr.hmdlal = le32_to_cpu(cmd->cdw13);
+    n->hmb_attr.hmdlau = le32_to_cpu(cmd->cdw14);
+    n->hmb_attr.hmdlec = le32_to_cpu(cmd->cdw15);
+}
+
 static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
     uint32_t dw10 = le32_to_cpu(cmd->cdw10);
@@ -638,6 +668,9 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
         req->cqe.result =
             cpu_to_le32((n->num_queues - 1) | ((n->num_queues - 1) << 16));
         break;
+    case NVME_HOST_MEMORY_BUFFER:
+        nvme_set_feature_hmb(n, cmd);
+        break;
     default:
         return NVME_INVALID_FIELD | NVME_DNR;
     }
@@ -985,6 +1018,8 @@ static int nvme_init(PCIDevice *pci_dev)
     id->oacs = cpu_to_le16(0);
     id->frmw = 7 << 1;
     id->lpa = 1 << 0;
+    id->hmpre = 0x2000;
+    id->hmmin = 0x0;
     id->sqes = (0x6 << 4) | 0x6;
     id->cqes = (0x4 << 4) | 0x4;
     id->nn = cpu_to_le32(n->num_namespaces);
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index 6aab338..fab748b 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -552,7 +552,10 @@ typedef struct NvmeIdCtrl {
     uint8_t     lpa;
     uint8_t     elpe;
     uint8_t     npss;
-    uint8_t     rsvd511[248];
+    uint8_t     rsvd271[8];
+    uint32_t    hmpre;
+    uint32_t    hmmin;
+    uint8_t     rsvd511[232];
     uint8_t     sqes;
     uint8_t     cqes;
     uint16_t    rsvd515;
@@ -623,9 +626,22 @@ enum NvmeFeatureIds {
     NVME_INTERRUPT_VECTOR_CONF      = 0x9,
     NVME_WRITE_ATOMICITY            = 0xa,
     NVME_ASYNCHRONOUS_EVENT_CONF    = 0xb,
+    NVME_HOST_MEMORY_BUFFER         = 0xd,
     NVME_SOFTWARE_PROGRESS_MARKER   = 0x80
 };
 
+typedef struct NvmeHmbFlag {
+    uint32_t    flag;
+} NvmeHmbFlag;
+
+typedef struct NvmeHmbAttr {
+    uint32_t    hsize;
+    uint32_t    hmdlal;
+    uint32_t    hmdlau;
+    uint32_t    hmdlec;
+    uint8_t     rsvd4095[4080];
+} NvmeHmbAttr;
+
 typedef struct NvmeRangeType {
     uint8_t     type;
     uint8_t     attributes;
@@ -776,6 +792,9 @@ typedef struct NvmeCtrl {
     uint32_t    cmbloc;
     uint8_t     *cmbuf;
 
+    NvmeHmbFlag hmb_flag;
+    NvmeHmbAttr hmb_attr;
+
     char            *serial;
     NvmeNamespace   *namespaces;
     NvmeSQueue      **sq;
-- 
2.7.4