[Skiboot] [PATCH V6 20/21] core/pldm: Add file io write request

[Frederic Barrat]

On 13/09/2022 12:27, Christophe Lombard wrote:
> Send/receive a PLDM WriteFile request message.
> 
> Due to maximum transfer size for PLDM protocol, we have to send several
> write requests, if necessary.
> 
> Signed-off-by: Christophe Lombard <clombard at linux.vnet.ibm.com>
> ---
>   core/pldm/pldm-file-io-requests.c | 123 ++++++++++++++++++++++++++++++
>   core/pldm/pldm.h                  |   2 +
>   2 files changed, 125 insertions(+)
> 
> diff --git a/core/pldm/pldm-file-io-requests.c b/core/pldm/pldm-file-io-requests.c
> index 48b00ef2..0665a679 100644
> --- a/core/pldm/pldm-file-io-requests.c
> +++ b/core/pldm/pldm-file-io-requests.c
> @@ -162,6 +162,129 @@ int pldm_file_io_read_file(uint32_t file_handle, uint32_t file_length,
>   	return read_file_req(file_handle, file_length, buf, offset, size);
>   }
>   
> +/*
> + * Send/receive a PLDM WriteFile request message.
> + */
> +static int write_file_req(uint32_t file_handle, const void *buf,
> +			  uint32_t offset, uint64_t size)
> +{


Unlike the read API, we don't have the file_size of the lid. Expected? 
Can we "grow" the file? what happens if we go over?


> +	void *response_msg, *current_ptr, *payload_data;
> +	uint32_t total_write, resp_length, request_length;
> +	size_t response_len, payload_len;
> +	uint8_t completion_code;
> +	int num_transfers;
> +	char *request_msg;
> +	int rc, i;
> +
> +	struct pldm_write_file_req file_req = {
> +		.file_handle = file_handle,
> +		.offset = offset,
> +		.length = size
> +	};
> +
> +	if (!size)
> +		return OPAL_PARAMETER;
> +
> +	if ((offset) && (offset > size))
> +		return OPAL_PARAMETER;
> +
> +	request_length = sizeof(struct pldm_msg_hdr) +
> +			 sizeof(struct pldm_write_file_req) +
> +			 size;
> +	request_msg = malloc(request_length);


zalloc()? (it's actually in the next patch)
We should check for a failed allocation.


> +
> +	payload_data = ((struct pldm_msg *)request_msg)->payload
> +			+ sizeof(file_req.file_handle)
> +			+ sizeof(file_req.offset)
> +			+ sizeof(file_req.length);


We could use offsetof(struct pldm_write_file_req, file_data)


> +	memcpy(payload_data, buf, size);
> +	current_ptr = payload_data;
> +	num_transfers = 1;
> +	total_write = 0;
> +
> +	if (size > MAX_TRANSFER_SIZE_BYTES) {
> +		num_transfers = (size + MAX_TRANSFER_SIZE_BYTES - 1) /
> +				MAX_TRANSFER_SIZE_BYTES;
> +		file_req.length = MAX_TRANSFER_SIZE_BYTES;
> +	}
> +
> +	prlog(PR_TRACE, "%s - file_handle: %d, offset: 0x%x, size: 0x%x, num_transfers: %d\n",
> +			__func__, file_handle, file_req.offset,
> +			file_req.length, num_transfers);
> +
> +	for (i = 0; i < num_transfers; i++) {
> +		file_req.offset = offset + (i * MAX_TRANSFER_SIZE_BYTES);
> +


I don't understand how it works when num_transfers > 1. Seems like we 
never update the content being sent over.


> +		/* Encode the file request */
> +		rc = encode_write_file_req(
> +				DEFAULT_INSTANCE_ID,
> +				file_req.file_handle,
> +				file_req.offset,
> +				file_req.length,
> +				(struct pldm_msg *)request_msg);
> +		if (rc != PLDM_SUCCESS) {
> +			prlog(PR_ERR, "Encode WriteFileReq Error, rc: %d\n", rc);
> +			free(request_msg);
> +			return OPAL_PARAMETER;
> +		}
> +
> +		/* Send and get the response message bytes */
> +		rc = pldm_requester_queue_and_wait(
> +					request_msg, request_length - 1,
> +					&response_msg, &response_len);
> +		if (rc) {
> +			prlog(PR_ERR, "Communication Error, req: WriteFileReq, rc: %d\n", rc);
> +			free(request_msg);
> +			return rc;
> +		}
> +
> +		/* Decode the message */
> +		payload_len = response_len - sizeof(struct pldm_msg_hdr);
> +		rc = decode_write_file_resp(
> +				response_msg,
> +				payload_len,
> +				&completion_code,
> +				&resp_length);
> +		if (rc != PLDM_SUCCESS || completion_code != PLDM_SUCCESS) {
> +			prlog(PR_ERR, "Decode WriteFileResp Error, rc: %d, cc: %d\n",
> +				      rc, completion_code);
> +			free(request_msg);
> +			free(response_msg);
> +			return OPAL_PARAMETER;
> +		}
> +
> +		if (resp_length == 0) {
> +			free(response_msg);
> +			break;
> +		}
> +
> +		total_write += resp_length;
> +		current_ptr += resp_length;
> +		free(response_msg);
> +
> +		if (total_write == size)
> +			break;
> +		else if (resp_length != file_req.length) {
> +			/* end of file */
> +			break;
> +		} else if (MAX_TRANSFER_SIZE_BYTES > (size - total_write))
> +			file_req.length = size - total_write;
> +	}
> +
> +	free(request_msg);
> +
> +	return OPAL_SUCCESS;
> +}
> +
> +int pldm_file_io_write_file(uint32_t file_handle, const void *buf,
> +			    uint32_t offset, uint64_t size)
> +{
> +	if (!file_io_ready)
> +		return OPAL_PARAMETER;
> +
> +	return write_file_req(file_handle, buf, offset, size);
> +}
> +
>   /*
>    * Send/receive a PLDM GetFileTable request message.
>    * The file table contains the list of files available and
> diff --git a/core/pldm/pldm.h b/core/pldm/pldm.h
> index 2b2a979d..688c7996 100644
> --- a/core/pldm/pldm.h
> +++ b/core/pldm/pldm.h
> @@ -49,6 +49,8 @@ int pldm_responder_init(void);
>   /* Requester support */
>   int pldm_file_io_read_file(uint32_t file_handle, uint32_t file_length,
>   			   void *buf, uint32_t offset, uint64_t size);
> +int pldm_file_io_write_file(uint32_t file_handle, const void *buf,
> +			    uint32_t offset, uint64_t size);
>   int pldm_file_io_init(void);
>   
>   int pldm_fru_get_bmc_version(void *bv);