Commit 1a22bc4b authored by Don Brace's avatar Don Brace Committed by Martin K. Petersen
Browse files

scsi: smartpqi: Refactor scatterlist code 

Factor out code common to all scatter-gather list building to prepare for
new AIO functionality. AIO (Accelerated I/O) requests go directly to disk

No functional changes.

Link: https://lore.kernel.org/r/161549372147.25025.9706613054649682229.stgit@brunhilda


Reviewed-by: default avatarScott Benesh <scott.benesh@microchip.com>
Reviewed-by: default avatarMike McGowen <mike.mcgowen@microchip.com>
Reviewed-by: default avatarScott Teel <scott.teel@microchip.com>
Reviewed-by: default avatarKevin Barnett <kevin.barnett@microchip.com>
Reviewed-by: default avatarMartin Wilck <mwilck@suse.com>
Signed-off-by: default avatarDon Brace <don.brace@microchip.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 281a817f

drivers/scsi/smartpqi/smartpqi_init.c

+42 −59
Original line number Diff line number Diff line
@@ -4857,16 +4857,52 @@ static inline void pqi_set_sg_descriptor( 
	put_unaligned_le32(0, &sg_descriptor->flags);

}



static unsigned int pqi_build_sg_list(struct pqi_sg_descriptor *sg_descriptor,

	struct scatterlist *sg, int sg_count, struct pqi_io_request *io_request,

	int max_sg_per_iu, bool *chained)

{

	int i;

	unsigned int num_sg_in_iu;



	*chained = false;

	i = 0;

	num_sg_in_iu = 0;

	max_sg_per_iu--;	/* Subtract 1 to leave room for chain marker. */



	while (1) {

		pqi_set_sg_descriptor(sg_descriptor, sg);

		if (!*chained)

			num_sg_in_iu++;

		i++;

		if (i == sg_count)

			break;

		sg_descriptor++;

		if (i == max_sg_per_iu) {

			put_unaligned_le64((u64)io_request->sg_chain_buffer_dma_handle,

				&sg_descriptor->address);

			put_unaligned_le32((sg_count - num_sg_in_iu) * sizeof(*sg_descriptor),

				&sg_descriptor->length);

			put_unaligned_le32(CISS_SG_CHAIN, &sg_descriptor->flags);

			*chained = true;

			num_sg_in_iu++;

			sg_descriptor = io_request->sg_chain_buffer;

		}

		sg = sg_next(sg);

	}



	put_unaligned_le32(CISS_SG_LAST, &sg_descriptor->flags);



	return num_sg_in_iu;

}



static int pqi_build_raid_sg_list(struct pqi_ctrl_info *ctrl_info,

	struct pqi_raid_path_request *request, struct scsi_cmnd *scmd,

	struct pqi_io_request *io_request)

{

	int i;

	u16 iu_length;

	int sg_count;

	bool chained;

	unsigned int num_sg_in_iu;

	unsigned int max_sg_per_iu;

	struct scatterlist *sg;

	struct pqi_sg_descriptor *sg_descriptor;
@@ -4882,36 +4918,10 @@ static int pqi_build_raid_sg_list(struct pqi_ctrl_info *ctrl_info, 


	sg = scsi_sglist(scmd);

	sg_descriptor = request->sg_descriptors;

	max_sg_per_iu = ctrl_info->max_sg_per_iu - 1;

	chained = false;

	num_sg_in_iu = 0;

	i = 0;



	while (1) {

		pqi_set_sg_descriptor(sg_descriptor, sg);

		if (!chained)

			num_sg_in_iu++;

		i++;

		if (i == sg_count)

			break;

		sg_descriptor++;

		if (i == max_sg_per_iu) {

			put_unaligned_le64(

				(u64)io_request->sg_chain_buffer_dma_handle,

				&sg_descriptor->address);

			put_unaligned_le32((sg_count - num_sg_in_iu)

				* sizeof(*sg_descriptor),

				&sg_descriptor->length);

			put_unaligned_le32(CISS_SG_CHAIN,

				&sg_descriptor->flags);

			chained = true;

			num_sg_in_iu++;

			sg_descriptor = io_request->sg_chain_buffer;

		}

		sg = sg_next(sg);

	}

	num_sg_in_iu = pqi_build_sg_list(sg_descriptor, sg, sg_count, io_request,

		ctrl_info->max_sg_per_iu, &chained);



	put_unaligned_le32(CISS_SG_LAST, &sg_descriptor->flags);

	request->partial = chained;

	iu_length += num_sg_in_iu * sizeof(*sg_descriptor);
@@ -4925,12 +4935,10 @@ static int pqi_build_aio_sg_list(struct pqi_ctrl_info *ctrl_info, 
	struct pqi_aio_path_request *request, struct scsi_cmnd *scmd,

	struct pqi_io_request *io_request)

{

	int i;

	u16 iu_length;

	int sg_count;

	bool chained;

	unsigned int num_sg_in_iu;

	unsigned int max_sg_per_iu;

	struct scatterlist *sg;

	struct pqi_sg_descriptor *sg_descriptor;
@@ -4947,35 +4955,10 @@ static int pqi_build_aio_sg_list(struct pqi_ctrl_info *ctrl_info, 


	sg = scsi_sglist(scmd);

	sg_descriptor = request->sg_descriptors;

	max_sg_per_iu = ctrl_info->max_sg_per_iu - 1;

	chained = false;

	i = 0;



	while (1) {

		pqi_set_sg_descriptor(sg_descriptor, sg);

		if (!chained)

			num_sg_in_iu++;

		i++;

		if (i == sg_count)

			break;

		sg_descriptor++;

		if (i == max_sg_per_iu) {

			put_unaligned_le64(

				(u64)io_request->sg_chain_buffer_dma_handle,

				&sg_descriptor->address);

			put_unaligned_le32((sg_count - num_sg_in_iu)

				* sizeof(*sg_descriptor),

				&sg_descriptor->length);

			put_unaligned_le32(CISS_SG_CHAIN,

				&sg_descriptor->flags);

			chained = true;

			num_sg_in_iu++;

			sg_descriptor = io_request->sg_chain_buffer;

		}

		sg = sg_next(sg);

	}

	num_sg_in_iu = pqi_build_sg_list(sg_descriptor, sg, sg_count, io_request,

		ctrl_info->max_sg_per_iu, &chained);



	put_unaligned_le32(CISS_SG_LAST, &sg_descriptor->flags);

	request->partial = chained;

	iu_length += num_sg_in_iu * sizeof(*sg_descriptor);