From 03aba2f79594ca94d159c8bab454de9bcc385b76 Mon Sep 17 00:00:00 2001 From: Luben Tuikov Date: Fri, 23 Jun 2006 09:39:09 -0700 Subject: [SCSI] sd/scsi_lib simplify sd_rw_intr and scsi_io_completion This patch simplifies "good_bytes" computation in sd_rw_intr(). sd: "good_bytes" computation is always done in terms of the resolution of the device's medium, since after that it is the number of good bytes we pass around and other layers/contexts (as opposed ot sd) can translate that to their own resolution (block layer:512). It also makes scsi_io_completion() processing more straightforward, eliminating the 3rd argument to the function. It also fixes a couple of bugs like not checking return value, using "break" instead of "return;", etc. I've been running with this patch for some time now on a test (do-it-all) system. Signed-off-by: Luben Tuikov Signed-off-by: James Bottomley --- drivers/scsi/sd.c | 143 +++++++++++++++++++++++------------------------------- 1 file changed, 62 insertions(+), 81 deletions(-) (limited to 'drivers/scsi/sd.c') diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 35419901124..f899ff0cf00 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -891,11 +891,10 @@ static struct block_device_operations sd_fops = { static void sd_rw_intr(struct scsi_cmnd * SCpnt) { int result = SCpnt->result; - int this_count = SCpnt->request_bufflen; - int good_bytes = (result == 0 ? this_count : 0); - sector_t block_sectors = 1; - u64 first_err_block; - sector_t error_sector; + unsigned int xfer_size = SCpnt->request_bufflen; + unsigned int good_bytes = result ? 0 : xfer_size; + u64 start_lba = SCpnt->request->sector; + u64 bad_lba; struct scsi_sense_hdr sshdr; int sense_valid = 0; int sense_deferred = 0; @@ -906,7 +905,6 @@ static void sd_rw_intr(struct scsi_cmnd * SCpnt) if (sense_valid) sense_deferred = scsi_sense_is_deferred(&sshdr); } - #ifdef CONFIG_SCSI_LOGGING SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: %s: res=0x%x\n", SCpnt->request->rq_disk->disk_name, result)); @@ -916,89 +914,72 @@ static void sd_rw_intr(struct scsi_cmnd * SCpnt) sshdr.sense_key, sshdr.asc, sshdr.ascq)); } #endif - /* - Handle MEDIUM ERRORs that indicate partial success. Since this is a - relatively rare error condition, no care is taken to avoid - unnecessary additional work such as memcpy's that could be avoided. - */ - if (driver_byte(result) != 0 && - sense_valid && !sense_deferred) { - switch (sshdr.sense_key) { - case MEDIUM_ERROR: - if (!blk_fs_request(SCpnt->request)) - break; - info_valid = scsi_get_sense_info_fld( - SCpnt->sense_buffer, SCSI_SENSE_BUFFERSIZE, - &first_err_block); - /* - * May want to warn and skip if following cast results - * in actual truncation (if sector_t < 64 bits) - */ - error_sector = (sector_t)first_err_block; - if (SCpnt->request->bio != NULL) - block_sectors = bio_sectors(SCpnt->request->bio); - switch (SCpnt->device->sector_size) { - case 1024: - error_sector <<= 1; - if (block_sectors < 2) - block_sectors = 2; - break; - case 2048: - error_sector <<= 2; - if (block_sectors < 4) - block_sectors = 4; - break; - case 4096: - error_sector <<=3; - if (block_sectors < 8) - block_sectors = 8; - break; - case 256: - error_sector >>= 1; - break; - default: - break; - } + if (driver_byte(result) != DRIVER_SENSE && + (!sense_valid || sense_deferred)) + goto out; - error_sector &= ~(block_sectors - 1); - good_bytes = (error_sector - SCpnt->request->sector) << 9; - if (good_bytes < 0 || good_bytes >= this_count) - good_bytes = 0; + switch (sshdr.sense_key) { + case HARDWARE_ERROR: + case MEDIUM_ERROR: + if (!blk_fs_request(SCpnt->request)) + goto out; + info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer, + SCSI_SENSE_BUFFERSIZE, + &bad_lba); + if (!info_valid) + goto out; + if (xfer_size <= SCpnt->device->sector_size) + goto out; + switch (SCpnt->device->sector_size) { + case 256: + start_lba <<= 1; break; - - case RECOVERED_ERROR: /* an error occurred, but it recovered */ - case NO_SENSE: /* LLDD got sense data */ - /* - * Inform the user, but make sure that it's not treated - * as a hard error. - */ - scsi_print_sense("sd", SCpnt); - SCpnt->result = 0; - memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); - good_bytes = this_count; + case 512: break; - - case ILLEGAL_REQUEST: - if (SCpnt->device->use_10_for_rw && - (SCpnt->cmnd[0] == READ_10 || - SCpnt->cmnd[0] == WRITE_10)) - SCpnt->device->use_10_for_rw = 0; - if (SCpnt->device->use_10_for_ms && - (SCpnt->cmnd[0] == MODE_SENSE_10 || - SCpnt->cmnd[0] == MODE_SELECT_10)) - SCpnt->device->use_10_for_ms = 0; + case 1024: + start_lba >>= 1; + break; + case 2048: + start_lba >>= 2; + break; + case 4096: + start_lba >>= 3; break; - default: + /* Print something here with limiting frequency. */ + goto out; break; } + /* This computation should always be done in terms of + * the resolution of the device's medium. + */ + good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size; + break; + case RECOVERED_ERROR: + case NO_SENSE: + /* Inform the user, but make sure that it's not treated + * as a hard error. + */ + scsi_print_sense("sd", SCpnt); + SCpnt->result = 0; + memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); + good_bytes = xfer_size; + break; + case ILLEGAL_REQUEST: + if (SCpnt->device->use_10_for_rw && + (SCpnt->cmnd[0] == READ_10 || + SCpnt->cmnd[0] == WRITE_10)) + SCpnt->device->use_10_for_rw = 0; + if (SCpnt->device->use_10_for_ms && + (SCpnt->cmnd[0] == MODE_SENSE_10 || + SCpnt->cmnd[0] == MODE_SELECT_10)) + SCpnt->device->use_10_for_ms = 0; + break; + default: + break; } - /* - * This calls the generic completion function, now that we know - * how many actual sectors finished, and how many sectors we need - * to say have failed. - */ - scsi_io_completion(SCpnt, good_bytes, block_sectors << 9); + out: + scsi_io_completion(SCpnt, good_bytes); } static int media_not_present(struct scsi_disk *sdkp, -- cgit v1.2.3