diff options
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh_alua.c | 65 |
1 files changed, 38 insertions, 27 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 1a970a76b1b9..6b729324b8d3 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -1,7 +1,7 @@ /* * Generic SCSI-3 ALUA SCSI Device Handler * - * Copyright (C) 2007, 2008 Hannes Reinecke, SUSE Linux Products GmbH. + * Copyright (C) 2007-2010 Hannes Reinecke, SUSE Linux Products GmbH. * All rights reserved. * * This program is free software; you can redistribute it and/or modify @@ -20,17 +20,19 @@ * */ #include <linux/slab.h> +#include <linux/delay.h> #include <scsi/scsi.h> #include <scsi/scsi_eh.h> #include <scsi/scsi_dh.h> #define ALUA_DH_NAME "alua" -#define ALUA_DH_VER "1.2" +#define ALUA_DH_VER "1.3" #define TPGS_STATE_OPTIMIZED 0x0 #define TPGS_STATE_NONOPTIMIZED 0x1 #define TPGS_STATE_STANDBY 0x2 #define TPGS_STATE_UNAVAILABLE 0x3 +#define TPGS_STATE_LBA_DEPENDENT 0x4 #define TPGS_STATE_OFFLINE 0xe #define TPGS_STATE_TRANSITIONING 0xf @@ -39,6 +41,7 @@ #define TPGS_SUPPORT_NONOPTIMIZED 0x02 #define TPGS_SUPPORT_STANDBY 0x04 #define TPGS_SUPPORT_UNAVAILABLE 0x08 +#define TPGS_SUPPORT_LBA_DEPENDENT 0x10 #define TPGS_SUPPORT_OFFLINE 0x40 #define TPGS_SUPPORT_TRANSITION 0x80 @@ -460,6 +463,8 @@ static char print_alua_state(int state) return 'S'; case TPGS_STATE_UNAVAILABLE: return 'U'; + case TPGS_STATE_LBA_DEPENDENT: + return 'L'; case TPGS_STATE_OFFLINE: return 'O'; case TPGS_STATE_TRANSITIONING: @@ -542,7 +547,9 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) int len, k, off, valid_states = 0; char *ucp; unsigned err; + unsigned long expiry, interval = 10; + expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT); retry: err = submit_rtpg(sdev, h); @@ -553,7 +560,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) return SCSI_DH_IO; err = alua_check_sense(sdev, &sense_hdr); - if (err == ADD_TO_MLQUEUE) + if (err == ADD_TO_MLQUEUE && time_before(jiffies, expiry)) goto retry; sdev_printk(KERN_INFO, sdev, "%s: rtpg sense code %02x/%02x/%02x\n", @@ -587,38 +594,37 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) } sdev_printk(KERN_INFO, sdev, - "%s: port group %02x state %c supports %c%c%c%c%c%c\n", + "%s: port group %02x state %c supports %c%c%c%c%c%c%c\n", ALUA_DH_NAME, h->group_id, print_alua_state(h->state), valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', + valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', valid_states&TPGS_SUPPORT_UNAVAILABLE?'U':'u', valid_states&TPGS_SUPPORT_STANDBY?'S':'s', valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); - if (h->tpgs & TPGS_MODE_EXPLICIT) { - switch (h->state) { - case TPGS_STATE_TRANSITIONING: + switch (h->state) { + case TPGS_STATE_TRANSITIONING: + if (time_before(jiffies, expiry)) { /* State transition, retry */ + interval *= 10; + msleep(interval); goto retry; - break; - case TPGS_STATE_OFFLINE: - /* Path is offline, fail */ - err = SCSI_DH_DEV_OFFLINED; - break; - default: - break; } - } else { - /* Only Implicit ALUA support */ - if (h->state == TPGS_STATE_OPTIMIZED || - h->state == TPGS_STATE_NONOPTIMIZED || - h->state == TPGS_STATE_STANDBY) - /* Useable path if active */ - err = SCSI_DH_OK; - else - /* Path unuseable for unavailable/offline */ - err = SCSI_DH_DEV_OFFLINED; + /* Transitioning time exceeded, set port to standby */ + err = SCSI_DH_RETRY; + h->state = TPGS_STATE_STANDBY; + break; + case TPGS_STATE_OFFLINE: + case TPGS_STATE_UNAVAILABLE: + /* Path unuseable for unavailable/offline */ + err = SCSI_DH_DEV_OFFLINED; + break; + default: + /* Useable path if active */ + err = SCSI_DH_OK; + break; } return err; } @@ -672,7 +678,9 @@ static int alua_activate(struct scsi_device *sdev, goto out; } - if (h->tpgs & TPGS_MODE_EXPLICIT && h->state != TPGS_STATE_OPTIMIZED) { + if (h->tpgs & TPGS_MODE_EXPLICIT && + h->state != TPGS_STATE_OPTIMIZED && + h->state != TPGS_STATE_LBA_DEPENDENT) { h->callback_fn = fn; h->callback_data = data; err = submit_stpg(h); @@ -698,8 +706,11 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req) struct alua_dh_data *h = get_alua_data(sdev); int ret = BLKPREP_OK; - if (h->state != TPGS_STATE_OPTIMIZED && - h->state != TPGS_STATE_NONOPTIMIZED) { + if (h->state == TPGS_STATE_TRANSITIONING) + ret = BLKPREP_DEFER; + else if (h->state != TPGS_STATE_OPTIMIZED && + h->state != TPGS_STATE_NONOPTIMIZED && + h->state != TPGS_STATE_LBA_DEPENDENT) { ret = BLKPREP_KILL; req->cmd_flags |= REQ_QUIET; } |