Re: [PATCH v13 16/18] cxl/mbox: Add support for PERFORM_MAINTENANCE mailbox command

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

On Wed, 9 Oct 2024 13:41:17 +0100
<shiju.jose@huawei.com> wrote:

> From: Shiju Jose <shiju.jose@huawei.com>
> 
> Add support for PERFORM_MAINTENANCE mailbox command.
> 
> CXL spec 3.1 section 8.2.9.7.1 describes the Perform Maintenance command.
> This command requests the device to execute the maintenance operation
> specified by the maintenance operation class and the maintenance operation
> subclass.
> 
> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
One trivial comment. With that tidied up
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/cxl/core/mbox.c | 40 ++++++++++++++++++++++++++++++++++++++++
>  drivers/cxl/cxlmem.h    | 17 +++++++++++++++++
>  2 files changed, 57 insertions(+)
> 
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 30c44ab11347..a6f69864c504 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -1084,6 +1084,46 @@ int cxl_set_feature(struct cxl_memdev_state *mds,
>  }
>  EXPORT_SYMBOL_NS_GPL(cxl_set_feature, CXL);
>  
> +int cxl_do_maintenance(struct cxl_memdev_state *mds,
> +		       u8 class, u8 subclass,
> +		       void *data_in, size_t data_in_size)
> +{
> +	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
> +	struct cxl_memdev_maintenance_pi {
> +		struct cxl_mbox_do_maintenance_hdr hdr;
> +		u8 data[];
> +	}  __packed;
> +	struct cxl_mbox_cmd mbox_cmd;
> +	size_t hdr_size;
> +	int rc = 0;
Always set, so no need to init.

> +
> +	struct cxl_memdev_maintenance_pi *pi __free(kfree) =
> +					kmalloc(cxl_mbox->payload_size, GFP_KERNEL);
> +	pi->hdr.op_class = class;
> +	pi->hdr.op_subclass = subclass;
> +	hdr_size = sizeof(pi->hdr);
> +	/*
> +	 * Check minimum mbox payload size is available for
> +	 * the maintenance data transfer.
> +	 */
> +	if (hdr_size + data_in_size > cxl_mbox->payload_size)
> +		return -ENOMEM;
> +
> +	memcpy(pi->data, data_in, data_in_size);
> +	mbox_cmd = (struct cxl_mbox_cmd) {
> +		.opcode = CXL_MBOX_OP_DO_MAINTENANCE,
> +		.size_in = hdr_size + data_in_size,
> +		.payload_in = pi,
> +	};
> +
> +	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
> +	if (rc < 0)
> +		return rc;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_do_maintenance, CXL);