sbp2: split sbp2_create_command_orb() for better readability
sbp2_create_command_orb() code cleanup:
- add two helper functions to reduce nesting depth
- omit the return value which was always ignored
- remove unnecessary declaration from sb2.h
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jody McIntyre <scjody@modernduck.com>
diff --git a/drivers/ieee1394/sbp2.c b/drivers/ieee1394/sbp2.c
index 5b9d03e..14b0c35 100644
--- a/drivers/ieee1394/sbp2.c
+++ b/drivers/ieee1394/sbp2.c
@@ -1707,26 +1707,184 @@
return 0;
}
+static void sbp2_prep_command_orb_sg(struct sbp2_command_orb *orb,
+ struct sbp2scsi_host_info *hi,
+ struct sbp2_command_info *command,
+ unsigned int scsi_use_sg,
+ struct scatterlist *sgpnt,
+ u32 orb_direction,
+ enum dma_data_direction dma_dir)
+{
+ command->dma_dir = dma_dir;
+ orb->data_descriptor_hi = ORB_SET_NODE_ID(hi->host->node_id);
+ orb->misc |= ORB_SET_DIRECTION(orb_direction);
+
+ /* Special case if only one element (and less than 64KB in size) */
+ if ((scsi_use_sg == 1) &&
+ (sgpnt[0].length <= SBP2_MAX_SG_ELEMENT_LENGTH)) {
+
+ SBP2_DEBUG("Only one s/g element");
+ command->dma_size = sgpnt[0].length;
+ command->dma_type = CMD_DMA_PAGE;
+ command->cmd_dma = pci_map_page(hi->host->pdev,
+ sgpnt[0].page,
+ sgpnt[0].offset,
+ command->dma_size,
+ command->dma_dir);
+ SBP2_DMA_ALLOC("single page scatter element");
+
+ orb->data_descriptor_lo = command->cmd_dma;
+ orb->misc |= ORB_SET_DATA_SIZE(command->dma_size);
+
+ } else {
+ struct sbp2_unrestricted_page_table *sg_element =
+ &command->scatter_gather_element[0];
+ u32 sg_count, sg_len;
+ dma_addr_t sg_addr;
+ int i, count = pci_map_sg(hi->host->pdev, sgpnt, scsi_use_sg,
+ dma_dir);
+
+ SBP2_DMA_ALLOC("scatter list");
+
+ command->dma_size = scsi_use_sg;
+ command->sge_buffer = sgpnt;
+
+ /* use page tables (s/g) */
+ orb->misc |= ORB_SET_PAGE_TABLE_PRESENT(0x1);
+ orb->data_descriptor_lo = command->sge_dma;
+
+ /*
+ * Loop through and fill out our sbp-2 page tables
+ * (and split up anything too large)
+ */
+ for (i = 0, sg_count = 0 ; i < count; i++, sgpnt++) {
+ sg_len = sg_dma_len(sgpnt);
+ sg_addr = sg_dma_address(sgpnt);
+ while (sg_len) {
+ sg_element[sg_count].segment_base_lo = sg_addr;
+ if (sg_len > SBP2_MAX_SG_ELEMENT_LENGTH) {
+ sg_element[sg_count].length_segment_base_hi =
+ PAGE_TABLE_SET_SEGMENT_LENGTH(SBP2_MAX_SG_ELEMENT_LENGTH);
+ sg_addr += SBP2_MAX_SG_ELEMENT_LENGTH;
+ sg_len -= SBP2_MAX_SG_ELEMENT_LENGTH;
+ } else {
+ sg_element[sg_count].length_segment_base_hi =
+ PAGE_TABLE_SET_SEGMENT_LENGTH(sg_len);
+ sg_len = 0;
+ }
+ sg_count++;
+ }
+ }
+
+ /* Number of page table (s/g) elements */
+ orb->misc |= ORB_SET_DATA_SIZE(sg_count);
+
+ sbp2util_packet_dump(sg_element,
+ (sizeof(struct sbp2_unrestricted_page_table)) * sg_count,
+ "sbp2 s/g list", command->sge_dma);
+
+ /* Byte swap page tables if necessary */
+ sbp2util_cpu_to_be32_buffer(sg_element,
+ (sizeof(struct sbp2_unrestricted_page_table)) *
+ sg_count);
+ }
+}
+
+static void sbp2_prep_command_orb_no_sg(struct sbp2_command_orb *orb,
+ struct sbp2scsi_host_info *hi,
+ struct sbp2_command_info *command,
+ struct scatterlist *sgpnt,
+ u32 orb_direction,
+ unsigned int scsi_request_bufflen,
+ void *scsi_request_buffer,
+ enum dma_data_direction dma_dir)
+{
+ command->dma_dir = dma_dir;
+ command->dma_size = scsi_request_bufflen;
+ command->dma_type = CMD_DMA_SINGLE;
+ command->cmd_dma = pci_map_single(hi->host->pdev, scsi_request_buffer,
+ command->dma_size, command->dma_dir);
+ orb->data_descriptor_hi = ORB_SET_NODE_ID(hi->host->node_id);
+ orb->misc |= ORB_SET_DIRECTION(orb_direction);
+
+ SBP2_DMA_ALLOC("single bulk");
+
+ /*
+ * Handle case where we get a command w/o s/g enabled (but
+ * check for transfers larger than 64K)
+ */
+ if (scsi_request_bufflen <= SBP2_MAX_SG_ELEMENT_LENGTH) {
+
+ orb->data_descriptor_lo = command->cmd_dma;
+ orb->misc |= ORB_SET_DATA_SIZE(scsi_request_bufflen);
+
+ } else {
+ struct sbp2_unrestricted_page_table *sg_element =
+ &command->scatter_gather_element[0];
+ u32 sg_count, sg_len;
+ dma_addr_t sg_addr;
+
+ /*
+ * Need to turn this into page tables, since the
+ * buffer is too large.
+ */
+ orb->data_descriptor_lo = command->sge_dma;
+
+ /* Use page tables (s/g) */
+ orb->misc |= ORB_SET_PAGE_TABLE_PRESENT(0x1);
+
+ /*
+ * fill out our sbp-2 page tables (and split up
+ * the large buffer)
+ */
+ sg_count = 0;
+ sg_len = scsi_request_bufflen;
+ sg_addr = command->cmd_dma;
+ while (sg_len) {
+ sg_element[sg_count].segment_base_lo = sg_addr;
+ if (sg_len > SBP2_MAX_SG_ELEMENT_LENGTH) {
+ sg_element[sg_count].length_segment_base_hi =
+ PAGE_TABLE_SET_SEGMENT_LENGTH(SBP2_MAX_SG_ELEMENT_LENGTH);
+ sg_addr += SBP2_MAX_SG_ELEMENT_LENGTH;
+ sg_len -= SBP2_MAX_SG_ELEMENT_LENGTH;
+ } else {
+ sg_element[sg_count].length_segment_base_hi =
+ PAGE_TABLE_SET_SEGMENT_LENGTH(sg_len);
+ sg_len = 0;
+ }
+ sg_count++;
+ }
+
+ /* Number of page table (s/g) elements */
+ orb->misc |= ORB_SET_DATA_SIZE(sg_count);
+
+ sbp2util_packet_dump(sg_element,
+ (sizeof(struct sbp2_unrestricted_page_table)) * sg_count,
+ "sbp2 s/g list", command->sge_dma);
+
+ /* Byte swap page tables if necessary */
+ sbp2util_cpu_to_be32_buffer(sg_element,
+ (sizeof(struct sbp2_unrestricted_page_table)) *
+ sg_count);
+ }
+}
+
/*
* This function is called to create the actual command orb and s/g list
* out of the scsi command itself.
*/
-static int sbp2_create_command_orb(struct scsi_id_instance_data *scsi_id,
- struct sbp2_command_info *command,
- unchar *scsi_cmd,
- unsigned int scsi_use_sg,
- unsigned int scsi_request_bufflen,
- void *scsi_request_buffer,
- enum dma_data_direction dma_dir)
+static void sbp2_create_command_orb(struct scsi_id_instance_data *scsi_id,
+ struct sbp2_command_info *command,
+ unchar *scsi_cmd,
+ unsigned int scsi_use_sg,
+ unsigned int scsi_request_bufflen,
+ void *scsi_request_buffer,
+ enum dma_data_direction dma_dir)
{
struct sbp2scsi_host_info *hi = scsi_id->hi;
struct scatterlist *sgpnt = (struct scatterlist *)scsi_request_buffer;
struct sbp2_command_orb *command_orb = &command->command_orb;
- struct sbp2_unrestricted_page_table *scatter_gather_element =
- &command->scatter_gather_element[0];
- u32 sg_count, sg_len, orb_direction;
- dma_addr_t sg_addr;
- int i;
+ u32 orb_direction;
/*
* Set-up our command ORB..
@@ -1753,186 +1911,29 @@
orb_direction = ORB_DIRECTION_NO_DATA_TRANSFER;
}
- /*
- * Set-up our pagetable stuff... unfortunately, this has become
- * messier than I'd like. Need to clean this up a bit. ;-)
- */
+ /* Set-up our pagetable stuff */
if (orb_direction == ORB_DIRECTION_NO_DATA_TRANSFER) {
-
SBP2_DEBUG("No data transfer");
-
- /*
- * Handle no data transfer
- */
command_orb->data_descriptor_hi = 0x0;
command_orb->data_descriptor_lo = 0x0;
command_orb->misc |= ORB_SET_DIRECTION(1);
-
} else if (scsi_use_sg) {
-
SBP2_DEBUG("Use scatter/gather");
-
- /*
- * Special case if only one element (and less than 64KB in size)
- */
- if ((scsi_use_sg == 1) && (sgpnt[0].length <= SBP2_MAX_SG_ELEMENT_LENGTH)) {
-
- SBP2_DEBUG("Only one s/g element");
- command->dma_dir = dma_dir;
- command->dma_size = sgpnt[0].length;
- command->dma_type = CMD_DMA_PAGE;
- command->cmd_dma = pci_map_page(hi->host->pdev,
- sgpnt[0].page,
- sgpnt[0].offset,
- command->dma_size,
- command->dma_dir);
- SBP2_DMA_ALLOC("single page scatter element");
-
- command_orb->data_descriptor_hi = ORB_SET_NODE_ID(hi->host->node_id);
- command_orb->data_descriptor_lo = command->cmd_dma;
- command_orb->misc |= ORB_SET_DATA_SIZE(command->dma_size);
- command_orb->misc |= ORB_SET_DIRECTION(orb_direction);
-
- } else {
- int count = pci_map_sg(hi->host->pdev, sgpnt, scsi_use_sg, dma_dir);
- SBP2_DMA_ALLOC("scatter list");
-
- command->dma_size = scsi_use_sg;
- command->dma_dir = dma_dir;
- command->sge_buffer = sgpnt;
-
- /* use page tables (s/g) */
- command_orb->misc |= ORB_SET_PAGE_TABLE_PRESENT(0x1);
- command_orb->misc |= ORB_SET_DIRECTION(orb_direction);
- command_orb->data_descriptor_hi = ORB_SET_NODE_ID(hi->host->node_id);
- command_orb->data_descriptor_lo = command->sge_dma;
-
- /*
- * Loop through and fill out our sbp-2 page tables
- * (and split up anything too large)
- */
- for (i = 0, sg_count = 0 ; i < count; i++, sgpnt++) {
- sg_len = sg_dma_len(sgpnt);
- sg_addr = sg_dma_address(sgpnt);
- while (sg_len) {
- scatter_gather_element[sg_count].segment_base_lo = sg_addr;
- if (sg_len > SBP2_MAX_SG_ELEMENT_LENGTH) {
- scatter_gather_element[sg_count].length_segment_base_hi =
- PAGE_TABLE_SET_SEGMENT_LENGTH(SBP2_MAX_SG_ELEMENT_LENGTH);
- sg_addr += SBP2_MAX_SG_ELEMENT_LENGTH;
- sg_len -= SBP2_MAX_SG_ELEMENT_LENGTH;
- } else {
- scatter_gather_element[sg_count].length_segment_base_hi =
- PAGE_TABLE_SET_SEGMENT_LENGTH(sg_len);
- sg_len = 0;
- }
- sg_count++;
- }
- }
-
- /* Number of page table (s/g) elements */
- command_orb->misc |= ORB_SET_DATA_SIZE(sg_count);
-
- sbp2util_packet_dump(scatter_gather_element,
- (sizeof(struct sbp2_unrestricted_page_table)) * sg_count,
- "sbp2 s/g list", command->sge_dma);
-
- /*
- * Byte swap page tables if necessary
- */
- sbp2util_cpu_to_be32_buffer(scatter_gather_element,
- (sizeof(struct sbp2_unrestricted_page_table)) *
- sg_count);
-
- }
-
+ sbp2_prep_command_orb_sg(command_orb, hi, command, scsi_use_sg,
+ sgpnt, orb_direction, dma_dir);
} else {
-
SBP2_DEBUG("No scatter/gather");
-
- command->dma_dir = dma_dir;
- command->dma_size = scsi_request_bufflen;
- command->dma_type = CMD_DMA_SINGLE;
- command->cmd_dma =
- pci_map_single(hi->host->pdev, scsi_request_buffer,
- command->dma_size, command->dma_dir);
- SBP2_DMA_ALLOC("single bulk");
-
- /*
- * Handle case where we get a command w/o s/g enabled (but
- * check for transfers larger than 64K)
- */
- if (scsi_request_bufflen <= SBP2_MAX_SG_ELEMENT_LENGTH) {
-
- command_orb->data_descriptor_hi = ORB_SET_NODE_ID(hi->host->node_id);
- command_orb->data_descriptor_lo = command->cmd_dma;
- command_orb->misc |= ORB_SET_DATA_SIZE(scsi_request_bufflen);
- command_orb->misc |= ORB_SET_DIRECTION(orb_direction);
-
- } else {
- /*
- * Need to turn this into page tables, since the
- * buffer is too large.
- */
- command_orb->data_descriptor_hi = ORB_SET_NODE_ID(hi->host->node_id);
- command_orb->data_descriptor_lo = command->sge_dma;
-
- /* Use page tables (s/g) */
- command_orb->misc |= ORB_SET_PAGE_TABLE_PRESENT(0x1);
- command_orb->misc |= ORB_SET_DIRECTION(orb_direction);
-
- /*
- * fill out our sbp-2 page tables (and split up
- * the large buffer)
- */
- sg_count = 0;
- sg_len = scsi_request_bufflen;
- sg_addr = command->cmd_dma;
- while (sg_len) {
- scatter_gather_element[sg_count].segment_base_lo = sg_addr;
- if (sg_len > SBP2_MAX_SG_ELEMENT_LENGTH) {
- scatter_gather_element[sg_count].length_segment_base_hi =
- PAGE_TABLE_SET_SEGMENT_LENGTH(SBP2_MAX_SG_ELEMENT_LENGTH);
- sg_addr += SBP2_MAX_SG_ELEMENT_LENGTH;
- sg_len -= SBP2_MAX_SG_ELEMENT_LENGTH;
- } else {
- scatter_gather_element[sg_count].length_segment_base_hi =
- PAGE_TABLE_SET_SEGMENT_LENGTH(sg_len);
- sg_len = 0;
- }
- sg_count++;
- }
-
- /* Number of page table (s/g) elements */
- command_orb->misc |= ORB_SET_DATA_SIZE(sg_count);
-
- sbp2util_packet_dump(scatter_gather_element,
- (sizeof(struct sbp2_unrestricted_page_table)) * sg_count,
- "sbp2 s/g list", command->sge_dma);
-
- /*
- * Byte swap page tables if necessary
- */
- sbp2util_cpu_to_be32_buffer(scatter_gather_element,
- (sizeof(struct sbp2_unrestricted_page_table)) *
- sg_count);
-
- }
-
+ sbp2_prep_command_orb_no_sg(command_orb, hi, command, sgpnt,
+ orb_direction, scsi_request_bufflen,
+ scsi_request_buffer, dma_dir);
}
- /*
- * Byte swap command ORB if necessary
- */
+ /* Byte swap command ORB if necessary */
sbp2util_cpu_to_be32_buffer(command_orb, sizeof(struct sbp2_command_orb));
- /*
- * Put our scsi command in the command ORB
- */
+ /* Put our scsi command in the command ORB */
memset(command_orb->cdb, 0, 12);
memcpy(command_orb->cdb, scsi_cmd, COMMAND_SIZE(*scsi_cmd));
-
- return 0;
}
/*