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scsi: sd: Have midlayer retry read_capacity_10() errors

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This has read_capacity_10() have the SCSI midlayer retry errors instead of
driving them itself.

There are 2 behavior changes with this patch:

 1. There is one behavior change where we no longer retry when
    scsi_execute_cmd() returns < 0, but we should be ok. We don't need to
    retry for failures like the queue being removed, and for the case where
    there are no tags/reqs since the block layer waits/retries for us. For
    possible memory allocation failures from blk_rq_map_kern() we use
    GFP_NOIO, so retrying will probably not help.

 2. For the specific UAs we checked for and retried, we would get
    READ_CAPACITY_RETRIES_ON_RESET retries plus whatever retries were left
    from the main loop's retries. Each UA now gets
    READ_CAPACITY_RETRIES_ON_RESET retries, and the other errors get up to
    3 retries. This is most likely ok, because
    READ_CAPACITY_RETRIES_ON_RESET is already 10 and is not based on
    anything specific like a spec or device, so the extra 3 we got from the
    main loop was probably just an accident and is not going to help.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20240123002220.129141-16-michael.christie@oracle.com
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Mike Christie 2024-01-22 18:22:16 -06:00 committed by Martin K. Petersen
parent eea6ef3792
commit 0f11328f2f
1 changed files with 39 additions and 23 deletions
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62
drivers/scsi/sd.c
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@ -2588,42 +2588,58 @@ static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
unsigned char *buffer)
{
unsigned char cmd[16];
static const u8 cmd[10] = { READ_CAPACITY };
struct scsi_sense_hdr sshdr;
struct scsi_failure failure_defs[] = {
/* Do not retry Medium Not Present */
{
.sense = UNIT_ATTENTION,
.asc = 0x3A,
.result = SAM_STAT_CHECK_CONDITION,
},
{
.sense = NOT_READY,
.asc = 0x3A,
.result = SAM_STAT_CHECK_CONDITION,
},
/* Device reset might occur several times so retry a lot */
{
.sense = UNIT_ATTENTION,
.asc = 0x29,
.allowed = READ_CAPACITY_RETRIES_ON_RESET,
.result = SAM_STAT_CHECK_CONDITION,
},
/* Any other error not listed above retry 3 times */
{
.result = SCMD_FAILURE_RESULT_ANY,
.allowed = 3,
},
{}
};
struct scsi_failures failures = {
.failure_definitions = failure_defs,
};
const struct scsi_exec_args exec_args = {
.sshdr = &sshdr,
.failures = &failures,
};
int sense_valid = 0;
int the_result;
int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
sector_t lba;
unsigned sector_size;
do {
cmd[0] = READ_CAPACITY;
memset(&cmd[1], 0, 9);
memset(buffer, 0, 8);
memset(buffer, 0, 8);
the_result = scsi_execute_cmd(sdp, cmd, REQ_OP_DRV_IN, buffer,
8, SD_TIMEOUT, sdkp->max_retries,
&exec_args);
the_result = scsi_execute_cmd(sdp, cmd, REQ_OP_DRV_IN, buffer,
8, SD_TIMEOUT, sdkp->max_retries,
&exec_args);
if (the_result > 0) {
sense_valid = scsi_sense_valid(&sshdr);
if (media_not_present(sdkp, &sshdr))
return -ENODEV;
if (the_result > 0) {
sense_valid = scsi_sense_valid(&sshdr);
if (sense_valid &&
sshdr.sense_key == UNIT_ATTENTION &&
sshdr.asc == 0x29 && sshdr.ascq == 0x00)
/* Device reset might occur several times,
* give it one more chance */
if (--reset_retries > 0)
continue;
}
retries--;
} while (the_result && retries);
}
if (the_result) {
sd_print_result(sdkp, "Read Capacity(10) failed", the_result);