From f7dcd31885cbe801cac95536a279bbc7e55af4f6 Mon Sep 17 00:00:00 2001
From: Klaus Jensen <k.jensen@samsung.com>
Date: Sun, 14 Feb 2021 19:09:27 +0100
Subject: [PATCH] hw/block/nvme: add non-mdts command size limit for verify

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>
Reviewed-by: Keith Busch <kbusch@kernel.org>
---
 hw/block/nvme.c | 34 ++++++++++++++++++++++++++++++----
 hw/block/nvme.h |  1 +
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index d754bd8e04..64cb966ab6 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -23,7 +23,8 @@
  *              [pmrdev=<mem_backend_file_id>,] \
  *              max_ioqpairs=<N[optional]>, \
  *              aerl=<N[optional]>,aer_max_queued=<N[optional]>, \
- *              mdts=<N[optional]>,zoned.zasl=<N[optional]>, \
+ *              mdts=<N[optional]>,vsl=<N[optional]>, \
+ *              zoned.zasl=<N[optional]>, \
  *              subsys=<subsys_id>
  *      -device nvme-ns,drive=<drive_id>,bus=<bus_name>,nsid=<nsid>,\
  *              zoned=<true|false[optional]>, \
@@ -78,12 +79,26 @@
  *   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.zasl`
  *   Indicates the maximum data transfer size for the Zone Append command. Like
  *   `mdts`, 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 0 (i.e.
  *   defaulting to the value of `mdts`).
  *
+ * - `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
+ *   ZASL = log2(<maximum append size> / <page size>), some values assigned
+ *   to this property may be rounded down and result in a lower maximum ZA
+ *   data size being in effect. By setting this property to 0, users can make
+ *   ZASL to be equal to MDTS. This property only affects zoned namespaces.
+ *
  * nvme namespace device parameters
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  * - `subsys`
@@ -2544,6 +2559,10 @@ 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);
@@ -4109,12 +4128,14 @@ static uint16_t nvme_identify_ctrl_csi(NvmeCtrl *n, NvmeRequest *req)
 {
     NvmeIdentify *c = (NvmeIdentify *)&req->cmd;
     uint8_t id[NVME_IDENTIFY_DATA_SIZE] = {};
+    NvmeIdCtrlNvm *id_nvm = (NvmeIdCtrlNvm *)&id;
 
     trace_pci_nvme_identify_ctrl_csi(c->csi);
 
     switch (c->csi) {
     case NVME_CSI_NVM:
-        ((NvmeIdCtrlNvm *)&id)->dmrsl = cpu_to_le32(n->dmrsl);
+        id_nvm->vsl = n->params.vsl;
+        id_nvm->dmrsl = cpu_to_le32(n->dmrsl);
         break;
 
     case NVME_CSI_ZONED:
@@ -5657,6 +5678,11 @@ static void nvme_check_constraints(NvmeCtrl *n, Error **errp)
                    "than or equal to mdts (Maximum Data Transfer Size)");
         return;
     }
+
+    if (!n->params.vsl) {
+        error_setg(errp, "vsl must be non-zero");
+        return;
+    }
 }
 
 static void nvme_init_state(NvmeCtrl *n)
@@ -5914,8 +5940,7 @@ 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
@@ -6058,6 +6083,7 @@ 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_UINT8("zoned.zasl", NvmeCtrl, params.zasl, 0),
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index 11c7fcc317..7b082212db 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -26,6 +26,7 @@ typedef struct NvmeParams {
     uint8_t  aerl;
     uint32_t aer_max_queued;
     uint8_t  mdts;
+    uint8_t  vsl;
     bool     use_intel_id;
     uint8_t  zasl;
     bool     legacy_cmb;