diff options
| author | Namjae Jeon <namjae.jeon@samsung.com> | 2012-07-07 23:05:08 -0400 |
|---|---|---|
| committer | James Bottomley <JBottomley@Parallels.com> | 2012-07-20 08:59:00 +0100 |
| commit | b81478d82e389dd0961760f5ff6f56b50d29db6d (patch) | |
| tree | 28729e5443db79591b693dea481b23d5511f37d1 | |
| parent | 365a7150094114a0f8ef0b6164e6b04b519039e8 (diff) | |
[SCSI] set to WCE if usb cache quirk is present.
Make use of USB quirk method to identify such HDD while reading
the cache status in sd_probe(). If cache quirk is present for
the HDD, lets assume that cache is enabled and make WCE bit
equal to 1.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
| -rw-r--r-- | drivers/scsi/sd.c | 9 | ||||
| -rw-r--r-- | include/scsi/scsi_device.h | 1 |
2 files changed, 8 insertions, 2 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 6e26db11250a..4df73e52a4f9 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2261,8 +2261,13 @@ bad_sense: sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n"); defaults: - sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n"); - sdkp->WCE = 0; + if (sdp->wce_default_on) { + sd_printk(KERN_NOTICE, sdkp, "Assuming drive cache: write back\n"); + sdkp->WCE = 1; + } else { + sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n"); + sdkp->WCE = 0; + } sdkp->RCD = 0; sdkp->DPOFUA = 0; } diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index bd1a14d89009..7539f52a33c9 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -154,6 +154,7 @@ struct scsi_device { unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */ unsigned try_rc_10_first:1; /* Try READ_CAPACACITY_10 first */ unsigned is_visible:1; /* is the device visible in sysfs */ + unsigned wce_default_on:1; /* Cache is ON by default */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ struct list_head event_list; /* asserted events */ |