lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[SCSI] sd/scsi_lib simplify sd_rw_intr and scsi_io_completion

Browse Source 
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 <ltuikov@yahoo.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This commit is contained in:
Luben Tuikov
2006-06-23 09:39:09 -07:00
committed by James Bottomley
parent f89d0a4e1d
commit 03aba2f795
4 changed files with 106 additions and 149 deletions
Download Patch File Download Diff File Expand all files Collapse all files

143
drivers/scsi/sd.c
View File

@@ -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,