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 --- This patch applies after "sbp2: delete sbp2scsi_direction_table". drivers/ieee1394/sbp2.c | 355 ++++++++++++++++++++++++------------------------ drivers/ieee1394/sbp2.h | 7 2 files changed, 178 insertions(+), 184 deletions(-) diff -uprN -X linux/Documentation/dontdiff linux/drivers/ieee1394-14.1/sbp2.c linux/drivers/ieee1394/sbp2.c --- linux/drivers/ieee1394-14.1/sbp2.c 2005-12-10 23:51:06.000000000 +0100 +++ linux/drivers/ieee1394/sbp2.c 2005-12-11 01:16:23.000000000 +0100 @@ -1709,26 +1709,184 @@ static int sbp2_agent_reset(struct scsi_ 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.. @@ -1755,186 +1913,29 @@ static int sbp2_create_command_orb(struc 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; } /* diff -uprN -X linux/Documentation/dontdiff linux/drivers/ieee1394-14.1/sbp2.h linux/drivers/ieee1394/sbp2.h --- linux/drivers/ieee1394-14.1/sbp2.h 2005-12-10 23:46:17.000000000 +0100 +++ linux/drivers/ieee1394/sbp2.h 2005-12-11 00:52:07.000000000 +0100 @@ -410,13 +410,6 @@ static int sbp2_logout_device(struct scs static int sbp2_handle_status_write(struct hpsb_host *host, int nodeid, int destid, quadlet_t *data, u64 addr, size_t length, u16 flags); static int sbp2_agent_reset(struct scsi_id_instance_data *scsi_id, int wait); -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 int sbp2_link_orb_command(struct scsi_id_instance_data *scsi_id, struct sbp2_command_info *command); static int sbp2_send_command(struct scsi_id_instance_data *scsi_id,