diff options
| author | Moger, Babu <Babu.Moger@lsi.com> | 2011-04-08 19:39:30 +0200 |
|---|---|---|
| committer | James Bottomley <James.Bottomley@suse.de> | 2011-05-01 17:47:41 +0200 |
| commit | 3425fbfe2293244abba72c80b215d09ead32d1ad (patch) | |
| tree | a0d9107f9d4fe3a235ad2cb24decd243114c4e1f /drivers/scsi/device_handler | |
| parent | [SCSI] scsi_dh_rdac : Detect the different RDAC operating modes (diff) | |
| download | linux-3425fbfe2293244abba72c80b215d09ead32d1ad.tar.xz linux-3425fbfe2293244abba72c80b215d09ead32d1ad.zip | |
[SCSI] scsi_dh_rdac : decide whether to send mode select based on operating mode
Based on the operating modes, handler decides whether to send mode
select or not. Purpose here is to reduce io-shipping as much as
possible whenever there is an option.
Signed-off-by: Babu Moger <babu.moger@lsi.com>
Reviewed-by: Yanling Qi <yanling.qi@lsi.com>
Reviewed-by: Sudhir Dachepalli <Sudhir.Dachepalli@lis.com>
Reviewed-by: Somasundaram Krishnasamy <Somasundaram.Krishnasamy@lsi.com>
Reviewed-by: Bob Stankey <Robert.Stankey@lsi.com>
Reviewed-by: Vijay Chauhan <Vijay.Chauhan@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Diffstat (limited to 'drivers/scsi/device_handler')
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh_rdac.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c index 4efe638036f6..e7fc70d6b478 100644 --- a/drivers/scsi/device_handler/scsi_dh_rdac.c +++ b/drivers/scsi/device_handler/scsi_dh_rdac.c @@ -670,12 +670,27 @@ static int rdac_activate(struct scsi_device *sdev, { struct rdac_dh_data *h = get_rdac_data(sdev); int err = SCSI_DH_OK; + int act = 0; err = check_ownership(sdev, h); if (err != SCSI_DH_OK) goto done; - if (h->lun_state == RDAC_LUN_UNOWNED) { + switch (h->mode) { + case RDAC_MODE: + if (h->lun_state == RDAC_LUN_UNOWNED) + act = 1; + break; + case RDAC_MODE_IOSHIP: + if ((h->lun_state == RDAC_LUN_UNOWNED) && + (h->preferred == RDAC_PREFERRED)) + act = 1; + break; + default: + break; + } + + if (act) { err = queue_mode_select(sdev, fn, data); if (err == SCSI_DH_OK) return 0; |