[PATCH v7 32/48] nvme: add check for mdts

[Klaus Jensen]

From: Klaus Jensen <address@hidden>

Add 'mdts' device parameter to control the Maximum Data Transfer Size of
the controller and check that it is respected.

Signed-off-by: Klaus Jensen <address@hidden>
Reviewed-by: Maxim Levitsky <address@hidden>
---
 hw/block/nvme.c       | 29 ++++++++++++++++++++++++++++-
 hw/block/nvme.h       |  4 +++-
 hw/block/trace-events |  1 +
 3 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 7528d75905d4..d8edd071b261 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -19,7 +19,8 @@
  *      -drive file=<file>,if=none,id=<drive_id>
  *      -device nvme,drive=<drive_id>,serial=<serial>,id=<id[optional]>, \
  *              cmb_size_mb=<cmb_size_mb[optional]>, \
- *              max_ioqpairs=<N[optional]>
+ *              max_ioqpairs=<N[optional]>, \
+ *              mdts=<mdts[optional]>
  *
  * Note cmb_size_mb denotes size of CMB in MB. CMB is assumed to be at
  * offset 0 in BAR2 and supports only WDS, RDS and SQS for now.
@@ -499,6 +500,19 @@ static void nvme_clear_events(NvmeCtrl *n, uint8_t 
event_type)
     }
 }
 
+static inline uint16_t nvme_check_mdts(NvmeCtrl *n, size_t len,
+                                       NvmeRequest *req)
+{
+    uint8_t mdts = n->params.mdts;
+
+    if (mdts && len > n->page_size << mdts) {
+        trace_nvme_dev_err_mdts(nvme_cid(req), n->page_size << mdts, len);
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+
+    return NVME_SUCCESS;
+}
+
 static inline uint16_t nvme_check_bounds(NvmeCtrl *n, NvmeNamespace *ns,
                                          uint64_t slba, uint32_t nlb,
                                          NvmeRequest *req)
@@ -593,6 +607,12 @@ static uint16_t nvme_rw(NvmeCtrl *n, NvmeNamespace *ns, 
NvmeCmd *cmd,
 
     trace_nvme_dev_rw(is_write ? "write" : "read", nlb, data_size, slba);
 
+    status = nvme_check_mdts(n, data_size, req);
+    if (status) {
+        block_acct_invalid(blk_get_stats(n->conf.blk), acct);
+        return status;
+    }
+
     status = nvme_check_bounds(n, ns, slba, nlb, req);
     if (status) {
         block_acct_invalid(blk_get_stats(n->conf.blk), acct);
@@ -884,6 +904,7 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeCmd *cmd, 
NvmeRequest *req)
     uint32_t numdl, numdu;
     uint64_t off, lpol, lpou;
     size_t   len;
+    uint16_t status;
 
     numdl = (dw10 >> 16);
     numdu = (dw11 & 0xffff);
@@ -899,6 +920,11 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeCmd *cmd, 
NvmeRequest *req)
 
     trace_nvme_dev_get_log(nvme_cid(req), lid, lsp, rae, len, off);
 
+    status = nvme_check_mdts(n, len, req);
+    if (status) {
+        return status;
+    }
+
     switch (lid) {
     case NVME_LOG_ERROR_INFO:
         return nvme_error_info(n, cmd, rae, len, off, req);
@@ -2033,6 +2059,7 @@ static void nvme_init_ctrl(NvmeCtrl *n)
     id->ieee[0] = 0x00;
     id->ieee[1] = 0x02;
     id->ieee[2] = 0xb3;
+    id->mdts = params->mdts;
     id->ver = cpu_to_le32(NVME_SPEC_VER);
     id->oacs = cpu_to_le16(0);
 
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index a946ae88d817..a25568723d0d 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -9,7 +9,8 @@
     DEFINE_PROP_UINT32("num_queues", _state, _props.num_queues, 0), \
     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)
+    DEFINE_PROP_UINT32("aer_max_queued", _state, _props.aer_max_queued, 64), \
+    DEFINE_PROP_UINT8("mdts", _state, _props.mdts, 7)
 
 typedef struct NvmeParams {
     char     *serial;
@@ -18,6 +19,7 @@ typedef struct NvmeParams {
     uint32_t cmb_size_mb;
     uint8_t  aerl;
     uint32_t aer_max_queued;
+    uint8_t  mdts;
 } NvmeParams;
 
 typedef struct NvmeAsyncEvent {
diff --git a/hw/block/trace-events b/hw/block/trace-events
index e050af87ece4..291422a5b77d 100644
--- a/hw/block/trace-events
+++ b/hw/block/trace-events
@@ -83,6 +83,7 @@ nvme_dev_mmio_doorbell_cq(uint16_t cqid, uint16_t new_head) 
"cqid %"PRIu16" new_
 nvme_dev_mmio_doorbell_sq(uint16_t sqid, uint16_t new_tail) "cqid %"PRIu16" 
new_tail %"PRIu16""
 
 # nvme traces for error conditions
+nvme_dev_err_mdts(uint16_t cid, size_t mdts, size_t len) "cid %"PRIu16" mdts 
%"PRIu64" len %"PRIu64""
 nvme_dev_err_invalid_dma(void) "PRP/SGL is too small for transfer size"
 nvme_dev_err_invalid_prplist_ent(uint64_t prplist) "PRP list entry is null or 
not page aligned: 0x%"PRIx64""
 nvme_dev_err_invalid_prp2_align(uint64_t prp2) "PRP2 is not page aligned: 
0x%"PRIx64""
-- 
2.26.0