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| author |   Dan Williams <dan.j.williams@intel.com> | 2014-02-06 12:23:15 -0800 |
|---|---|---|
| committer |   James Bottomley <JBottomley@Parallels.com> | 2014-03-15 10:18:53 -0700 |
| commit | 2193b1b16cc7c690f74f917c50004dd00c99088e (patch) | |
| tree | 3cc6191d585038c9515574a0efdca51117955b20 /drivers/scsi/isci | |
| parent | [SCSI] libsas: introduce scmd_dbg() to quiet false positive "timeout" messages (diff) | |
| download | linux-dev-2193b1b16cc7c690f74f917c50004dd00c99088e.tar.xz linux-dev-2193b1b16cc7c690f74f917c50004dd00c99088e.zip | |
[SCSI] isci: fix needless ata reset escalations
isci is needlessly tying libata's hands by returning
SAM_STAT_CHECK_CONDITION to some ata errors. Instead, prefer
SAS_PROTO_RESPONSE to let libata (via sas_ata_task_done()) disposition
the device-to-host fis.
For example isci is triggering an HSM Violation where AHCI is showing a
simple media error for the same bus condition:
isci:
ata7.00: failed command: READ VERIFY SECTOR(S)
ata7.00: cmd 40/00:01:00:00:00/00:00:00:00:00/e0 tag 0
res 01/04:00:00:00:00/00:00:00:00:00/e0 Emask 0x3 (HSM violation)
ahci:
ata6.00: failed command: READ VERIFY SECTOR(S)
ata6.00: cmd 40/00:01:00:00:00/00:00:00:00:00/e0 tag 0
res 51/40:01:00:00:00/00:00:00:00:00/e0 Emask 0x9 (media error)
Note that the isci response matches this from sas_ata_task_done():
/* We saw a SAS error. Send a vague error. */
[..]
dev->sata_dev.fis[3] = 0x04; /* status err */
dev->sata_dev.fis[2] = ATA_ERR;
The end effect is that isci is needlessly triggering hard resets when
they are not necessary.
Reported-by: Xun Ni <xun.ni@intel.com>
Tested-by: Nelson Cheng <nelson.cheng@intel.com>
Acked-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/isci')
| -rw-r--r-- | drivers/scsi/isci/request.c | 8 |
1 files changed, 2 insertions, 6 deletions
diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c index 99d2930b18c8..56e38096f0c4 100644 --- a/drivers/scsi/isci/request.c +++ b/drivers/scsi/isci/request.c @@ -2723,13 +2723,9 @@ static void isci_process_stp_response(struct sas_task *task, struct dev_to_host_ memcpy(resp->ending_fis, fis, sizeof(*fis)); ts->buf_valid_size = sizeof(*resp); - /* If the device fault bit is set in the status register, then - * set the sense data and return. - */ - if (fis->status & ATA_DF) + /* If an error is flagged let libata decode the fis */ + if (ac_err_mask(fis->status)) ts->stat = SAS_PROTO_RESPONSE; - else if (fis->status & ATA_ERR) - ts->stat = SAM_STAT_CHECK_CONDITION; else ts->stat = SAM_STAT_GOOD; |