Re: [PATCH v2 3/6] tools/testing/cxl: Mock the Inject Poison mailbox command

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Wed, 18 Jan 2023 21:00:18 -0800
alison.schofield@intel.com wrote:

> From: Alison Schofield <alison.schofield@intel.com>
> 
> Mock the injection of poison by storing the device:address entries in
> mock_poison_list[]. Enforce a limit of 8 poison injections per memdev
> device and 128 total entries for the cxl_test mock driver.
> 
> Introducing the mock_poison[] list here, makes it available for use in
> the mock of Clear Poison, and the mock of Get Poison List.
> 
> Signed-off-by: Alison Schofield <alison.schofield@intel.com>

I'm not that keen on the global nature of the list, but maybe that's
enough for this test for now at least. Nothing stops us making it more
flexible later.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  tools/testing/cxl/test/mem.c | 77 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 77 insertions(+)
> 
> diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
> index 09dc358bb33b..b0ecdc4e7c87 100644
> --- a/tools/testing/cxl/test/mem.c
> +++ b/tools/testing/cxl/test/mem.c
> @@ -14,6 +14,9 @@
>  #define DEV_SIZE SZ_2G
>  #define EFFECT(x) (1U << x)
>  
> +#define MOCK_INJECT_DEV_MAX 8
> +#define MOCK_INJECT_TEST_MAX 128
> +
>  static struct cxl_cel_entry mock_cel[] = {
>  	{
>  		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_SUPPORTED_LOGS),
> @@ -43,6 +46,10 @@ static struct cxl_cel_entry mock_cel[] = {
>  		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_POISON),
>  		.effect = cpu_to_le16(0),
>  	},
> +	{
> +		.opcode = cpu_to_le16(CXL_MBOX_OP_INJECT_POISON),
> +		.effect = cpu_to_le16(0),
> +	},
>  };
>  
>  /* See CXL 2.0 Table 181 Get Health Info Output Payload */
> @@ -144,6 +151,7 @@ static int mock_id(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
>  			cpu_to_le64(SZ_256M / CXL_CAPACITY_MULTIPLIER),
>  		.total_capacity =
>  			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
> +		.inject_poison_limit = cpu_to_le16(MOCK_INJECT_DEV_MAX),
>  	};
>  
>  	put_unaligned_le24(CXL_POISON_LIST_MAX, id.poison_list_max_mer);
> @@ -565,6 +573,11 @@ static int mock_health_info(struct cxl_dev_state *cxlds,
>  	return 0;
>  }
>  
> +static struct mock_poison {
> +	struct cxl_dev_state *cxlds;
> +	u64 dpa;
> +} mock_poison_list[MOCK_INJECT_TEST_MAX];
> +
>  static int mock_get_poison(struct cxl_dev_state *cxlds,
>  			   struct cxl_mbox_cmd *cmd)
>  {
> @@ -593,6 +606,67 @@ static int mock_get_poison(struct cxl_dev_state *cxlds,
>  	return 0;
>  }
>  
> +static bool mock_poison_dev_max_injected(struct cxl_dev_state *cxlds)
> +{
> +	int count = 0;
> +
> +	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
> +		if (mock_poison_list[i].cxlds == cxlds)
> +			count++;
> +	}
> +	return (count >= MOCK_INJECT_DEV_MAX);
> +}
> +
> +static bool mock_poison_add(struct cxl_dev_state *cxlds, u64 dpa)
> +{
> +	if (mock_poison_dev_max_injected(cxlds)) {
> +		dev_dbg(cxlds->dev,
> +			"Device poison injection limit has been reached: %d\n",
> +			MOCK_INJECT_DEV_MAX);
> +		return false;
> +	}
> +
> +	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
> +		if (!mock_poison_list[i].cxlds) {
> +			mock_poison_list[i].cxlds = cxlds;
> +			mock_poison_list[i].dpa = dpa;
> +			return true;
> +		}
> +	}
> +	dev_dbg(cxlds->dev,
> +		"Mock test poison injection limit has been reached: %d\n",
> +		MOCK_INJECT_TEST_MAX);
> +
> +	return false;
> +}
> +
> +static bool mock_poison_found(struct cxl_dev_state *cxlds, u64 dpa)
> +{
> +	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
> +		if (mock_poison_list[i].cxlds == cxlds &&
> +		    mock_poison_list[i].dpa == dpa)
> +			return true;
> +	}
> +	return false;
> +}
> +
> +static int mock_inject_poison(struct cxl_dev_state *cxlds,
> +			      struct cxl_mbox_cmd *cmd)
> +{
> +	struct cxl_mbox_inject_poison *pi = cmd->payload_in;
> +	u64 dpa = le64_to_cpu(pi->address);
> +
> +	if (mock_poison_found(cxlds, dpa)) {
> +		/* Not an error to inject poison if already poisoned */
> +		dev_dbg(cxlds->dev, "DPA: 0x%llx already poisoned\n", dpa);
> +		return 0;
> +	}
> +	if (!mock_poison_add(cxlds, dpa))
> +		return -ENXIO;
> +
> +	return 0;
> +}
> +
>  static int cxl_mock_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
>  {
>  	struct device *dev = cxlds->dev;
> @@ -644,6 +718,9 @@ static int cxl_mock_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *
>  	case CXL_MBOX_OP_GET_POISON:
>  		rc = mock_get_poison(cxlds, cmd);
>  		break;
> +	case CXL_MBOX_OP_INJECT_POISON:
> +		rc = mock_inject_poison(cxlds, cmd);
> +		break;
>  	default:
>  		break;
>  	}