[PATCH RFC v3 10/12] hw/block/nvme: add non-mdts command size limit for verify

[Klaus Jensen <its@irrelevant.dk>]

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

Verify is not subject to MDTS, so a single Verify command may result in
excessive amounts of allocated memory. Impose a limit on the data size
by adding support for TP 4040 ("Non-MDTS Command Size Limits").

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 hw/block/nvme.h      |  1 +
 include/block/nvme.h |  5 +++++
 hw/block/nvme.c      | 50 +++++++++++++++++++++++++++++++++-----------
 3 files changed, 44 insertions(+), 12 deletions(-)

diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index 3b8ed73d2a04..d1b09ece1985 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -19,6 +19,7 @@ typedef struct NvmeParams {
     uint8_t  aerl;
     uint32_t aer_max_queued;
     uint8_t  mdts;
+    uint8_t  vsl;
     bool     use_intel_id;
     uint32_t zasl_bs;
     bool     legacy_cmb;
diff --git a/include/block/nvme.h b/include/block/nvme.h
index c2fd7e817e5d..ec5262d17e12 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -1042,6 +1042,11 @@ typedef struct QEMU_PACKED NvmeIdCtrl {
     uint8_t     vs[1024];
 } NvmeIdCtrl;
 
+typedef struct NvmeIdCtrlNvm {
+    uint8_t     vsl;
+    uint8_t     rsvd1[4095];
+} NvmeIdCtrlNvm;
+
 typedef struct NvmeIdCtrlZoned {
     uint8_t     zasl;
     uint8_t     rsvd1[4095];
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 7b366f979a1c..e5832ce2a69e 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -22,7 +22,8 @@
  *              [pmrdev=<mem_backend_file_id>,] \
  *              max_ioqpairs=<N[optional]>, \
  *              aerl=<N[optional]>, aer_max_queued=<N[optional]>, \
- *              mdts=<N[optional]>,zoned.append_size_limit=<N[optional]>, \
+ *              mdts=<N[optional]>,vsl=<N[optional]>, \
+ *              zoned.append_size_limit=<N[optional]>, \
  *              subsys=<subsys_id> \
  *      -device nvme-ns,drive=<drive_id>,bus=<bus_name>,nsid=<nsid>,\
  *              zoned=<true|false[optional]>, \
@@ -63,6 +64,18 @@
  *   completion when there are no outstanding AERs. When the maximum number of
  *   enqueued events are reached, subsequent events will be dropped.
  *
+ * - `mdts`
+ *   Indicates the maximum data transfer size for a command that transfers data
+ *   between host-accessible memory and the controller. The value is specified
+ *   as a power of two (2^n) and is in units of the minimum memory page size
+ *   (CAP.MPSMIN). The default value is 7 (i.e. 512 KiB).
+ *
+ * - `vsl`
+ *   Indicates the maximum data size limit for the Verify command. Like `mdts`,
+ *   this value is specified as a power of two (2^n) and is in units of the
+ *   minimum memory page size (CAP.MPSMIN). The default value is 7 (i.e. 512
+ *   KiB).
+ *
  * - `zoned.append_size_limit`
  *   The maximum I/O size in bytes that is allowed in Zone Append command.
  *   The default is 128KiB. Since internally this this value is maintained as
@@ -2866,6 +2879,10 @@ static uint16_t nvme_verify(NvmeCtrl *n, NvmeRequest *req)
         }
     }
 
+    if (len > n->page_size << n->params.vsl) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+
     status = nvme_check_bounds(ns, slba, nlb);
     if (status) {
         trace_pci_nvme_err_invalid_lba_range(slba, nlb, ns->id_ns.nsze);
@@ -4551,20 +4568,24 @@ static uint16_t nvme_identify_ctrl(NvmeCtrl *n, NvmeRequest *req)
 static uint16_t nvme_identify_ctrl_csi(NvmeCtrl *n, NvmeRequest *req)
 {
     NvmeIdentify *c = (NvmeIdentify *)&req->cmd;
-    NvmeIdCtrlZoned id = {};
+    uint8_t id[NVME_IDENTIFY_DATA_SIZE] = {};
 
     trace_pci_nvme_identify_ctrl_csi(c->csi);
 
-    if (c->csi == NVME_CSI_NVM) {
-        return nvme_rpt_empty_id_struct(n, req);
-    } else if (c->csi == NVME_CSI_ZONED) {
-        if (n->params.zasl_bs) {
-            id.zasl = n->zasl;
-        }
-        return nvme_c2h(n, (uint8_t *)&id, sizeof(id), req);
+    switch (c->csi) {
+    case NVME_CSI_NVM:
+        ((NvmeIdCtrlNvm *)&id)->vsl = n->params.vsl;
+        break;
+
+    case NVME_CSI_ZONED:
+        ((NvmeIdCtrlZoned *)&id)->zasl = n->zasl;
+        break;
+
+    default:
+        return NVME_INVALID_FIELD | NVME_DNR;
     }
 
-    return NVME_INVALID_FIELD | NVME_DNR;
+    return nvme_c2h(n, id, sizeof(id), req);
 }
 
 static uint16_t nvme_identify_ns(NvmeCtrl *n, NvmeRequest *req)
@@ -5968,6 +5989,11 @@ static void nvme_check_constraints(NvmeCtrl *n, Error **errp)
             return;
         }
     }
+
+    if (!n->params.vsl) {
+        error_setg(errp, "vsl must be non-zero");
+        return;
+    }
 }
 
 static void nvme_init_state(NvmeCtrl *n)
@@ -6190,8 +6216,7 @@ static void nvme_init_ctrl(NvmeCtrl *n, PCIDevice *pci_dev)
     id->nn = cpu_to_le32(n->num_namespaces);
     id->oncs = cpu_to_le16(NVME_ONCS_WRITE_ZEROES | NVME_ONCS_TIMESTAMP |
                            NVME_ONCS_FEATURES | NVME_ONCS_DSM |
-                           NVME_ONCS_COMPARE | NVME_ONCS_COPY |
-                           NVME_ONCS_VERIFY);
+                           NVME_ONCS_COMPARE | NVME_ONCS_COPY);
 
     /*
      * NOTE: If this device ever supports a command set that does NOT use 0x0
@@ -6334,6 +6359,7 @@ static Property nvme_props[] = {
     DEFINE_PROP_UINT8("aerl", NvmeCtrl, params.aerl, 3),
     DEFINE_PROP_UINT32("aer_max_queued", NvmeCtrl, params.aer_max_queued, 64),
     DEFINE_PROP_UINT8("mdts", NvmeCtrl, params.mdts, 7),
+    DEFINE_PROP_UINT8("vsl", NvmeCtrl, params.vsl, 7),
     DEFINE_PROP_BOOL("use-intel-id", NvmeCtrl, params.use_intel_id, false),
     DEFINE_PROP_BOOL("legacy-cmb", NvmeCtrl, params.legacy_cmb, false),
     DEFINE_PROP_SIZE32("zoned.append_size_limit", NvmeCtrl, params.zasl_bs,
-- 
2.30.0