diff options
| author |   Moger, Babu <Babu.Moger@netapp.com> | 2012-03-27 20:56:08 +0000 |
|---|---|---|
| committer |   James Bottomley <JBottomley@Parallels.com> | 2012-04-23 19:28:13 +0100 |
| commit | dcd3a754b8c811441326d68574598fb3b4976ff4 (patch) | |
| tree | bad1efd7f910d4f84760e733626b2edd84098822 /drivers/scsi/device_handler | |
| parent | [SCSI] scsi_dh_alua: Inroduce the set_params interface scsi_dh_alua handler (diff) | |
| download | linux-dev-dcd3a754b8c811441326d68574598fb3b4976ff4.tar.xz linux-dev-dcd3a754b8c811441326d68574598fb3b4976ff4.zip | |
[SCSI] scsi_dh_alua: Store the PREF bit from RTPG
PREF bit indicates preferred target port group for accessing a logical
unit. This bit is used to optimize the STPG command handling.
Signed-off-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/device_handler')
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh_alua.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 506206ae5755..4865a99d9c38 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -63,6 +63,7 @@ struct alua_dh_data { int rel_port; int tpgs; int state; + int pref; unsigned flags; /* used for optimizing STPG */ unsigned char inq[ALUA_INQUIRY_SIZE]; unsigned char *buff; @@ -558,14 +559,16 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) for (k = 4, ucp = h->buff + 4; k < len; k += off, ucp += off) { if (h->group_id == (ucp[2] << 8) + ucp[3]) { h->state = ucp[0] & 0x0f; + h->pref = ucp[0] >> 7; valid_states = ucp[1]; } off = 8 + (ucp[7] * 4); } sdev_printk(KERN_INFO, sdev, - "%s: port group %02x state %c supports %c%c%c%c%c%c%c\n", + "%s: port group %02x state %c %s supports %c%c%c%c%c%c%c\n", ALUA_DH_NAME, h->group_id, print_alua_state(h->state), + h->pref ? "preferred" : "non-preferred", valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', |