diff options
Diffstat (limited to 'drivers/scsi/device_handler/scsi_dh_alua.c')
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh_alua.c | 188 |
1 files changed, 160 insertions, 28 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 04c5cea47a2..7bcf67eec92 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -46,23 +46,32 @@ #define TPGS_SUPPORT_OFFLINE 0x40 #define TPGS_SUPPORT_TRANSITION 0x80 +#define RTPG_FMT_MASK 0x70 +#define RTPG_FMT_EXT_HDR 0x10 + #define TPGS_MODE_UNINITIALIZED -1 #define TPGS_MODE_NONE 0x0 #define TPGS_MODE_IMPLICIT 0x1 #define TPGS_MODE_EXPLICIT 0x2 #define ALUA_INQUIRY_SIZE 36 -#define ALUA_FAILOVER_TIMEOUT (60 * HZ) +#define ALUA_FAILOVER_TIMEOUT 60 #define ALUA_FAILOVER_RETRIES 5 +/* flags passed from user level */ +#define ALUA_OPTIMIZE_STPG 1 + struct alua_dh_data { int group_id; int rel_port; int tpgs; int state; + int pref; + unsigned flags; /* used for optimizing STPG */ unsigned char inq[ALUA_INQUIRY_SIZE]; unsigned char *buff; int bufflen; + unsigned char transition_tmo; unsigned char sense[SCSI_SENSE_BUFFERSIZE]; int senselen; struct scsi_device *sdev; @@ -111,6 +120,7 @@ static struct request *get_alua_req(struct scsi_device *sdev, "%s: blk_get_request failed\n", __func__); return NULL; } + blk_rq_set_block_pc(rq); if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) { blk_put_request(rq); @@ -119,11 +129,10 @@ static struct request *get_alua_req(struct scsi_device *sdev, return NULL; } - rq->cmd_type = REQ_TYPE_BLOCK_PC; rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER; rq->retries = ALUA_FAILOVER_RETRIES; - rq->timeout = ALUA_FAILOVER_TIMEOUT; + rq->timeout = ALUA_FAILOVER_TIMEOUT * HZ; return rq; } @@ -169,7 +178,8 @@ done: * submit_rtpg - Issue a REPORT TARGET GROUP STATES command * @sdev: sdev the command should be sent to */ -static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) +static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, + bool rtpg_ext_hdr_req) { struct request *rq; int err = SCSI_DH_RES_TEMP_UNAVAIL; @@ -180,7 +190,10 @@ static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) /* Prepare the command. */ rq->cmd[0] = MAINTENANCE_IN; - rq->cmd[1] = MI_REPORT_TARGET_PGS; + if (rtpg_ext_hdr_req) + rq->cmd[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT; + else + rq->cmd[1] = MI_REPORT_TARGET_PGS; rq->cmd[6] = (h->bufflen >> 24) & 0xff; rq->cmd[7] = (h->bufflen >> 16) & 0xff; rq->cmd[8] = (h->bufflen >> 8) & 0xff; @@ -219,13 +232,13 @@ static void stpg_endio(struct request *req, int error) struct scsi_sense_hdr sense_hdr; unsigned err = SCSI_DH_OK; - if (error || host_byte(req->errors) != DID_OK || - msg_byte(req->errors) != COMMAND_COMPLETE) { + if (host_byte(req->errors) != DID_OK || + msg_byte(req->errors) != COMMAND_COMPLETE) { err = SCSI_DH_IO; goto done; } - if (h->senselen > 0) { + if (req->sense_len > 0) { err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, &sense_hdr); if (!err) { @@ -242,7 +255,9 @@ static void stpg_endio(struct request *req, int error) ALUA_DH_NAME, sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq); err = SCSI_DH_IO; - } + } else if (error) + err = SCSI_DH_IO; + if (err == SCSI_DH_OK) { h->state = TPGS_STATE_OPTIMIZED; sdev_printk(KERN_INFO, h->sdev, @@ -466,6 +481,11 @@ static int alua_check_sense(struct scsi_device *sdev, * Power On, Reset, or Bus Device Reset, just retry. */ return ADD_TO_MLQUEUE; + if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04) + /* + * Device internal reset + */ + return ADD_TO_MLQUEUE; if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01) /* * Mode Parameters Changed @@ -502,22 +522,30 @@ static int alua_check_sense(struct scsi_device *sdev, /* * alua_rtpg - Evaluate REPORT TARGET GROUP STATES * @sdev: the device to be evaluated. + * @wait_for_transition: if nonzero, wait ALUA_FAILOVER_TIMEOUT seconds for device to exit transitioning state * * Evaluate the Target Port Group State. * Returns SCSI_DH_DEV_OFFLINED if the path is * found to be unusable. */ -static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) +static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_for_transition) { struct scsi_sense_hdr sense_hdr; int len, k, off, valid_states = 0; unsigned char *ucp; unsigned err; - unsigned long expiry, interval = 1000; + bool rtpg_ext_hdr_req = 1; + unsigned long expiry, interval = 0; + unsigned int tpg_desc_tbl_off; + unsigned char orig_transition_tmo; + + if (!h->transition_tmo) + expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT * HZ); + else + expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ); - expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT); retry: - err = submit_rtpg(sdev, h); + err = submit_rtpg(sdev, h, rtpg_ext_hdr_req); if (err == SCSI_DH_IO && h->senselen > 0) { err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, @@ -525,6 +553,21 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) if (!err) return SCSI_DH_IO; + /* + * submit_rtpg() has failed on existing arrays + * when requesting extended header info, and + * the array doesn't support extended headers, + * even though it shouldn't according to T10. + * The retry without rtpg_ext_hdr_req set + * handles this. + */ + if (rtpg_ext_hdr_req == 1 && + sense_hdr.sense_key == ILLEGAL_REQUEST && + sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) { + rtpg_ext_hdr_req = 0; + goto retry; + } + err = alua_check_sense(sdev, &sense_hdr); if (err == ADD_TO_MLQUEUE && time_before(jiffies, expiry)) goto retry; @@ -551,17 +594,40 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) goto retry; } - for (k = 4, ucp = h->buff + 4; k < len; k += off, ucp += off) { + orig_transition_tmo = h->transition_tmo; + if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && h->buff[5] != 0) + h->transition_tmo = h->buff[5]; + else + h->transition_tmo = ALUA_FAILOVER_TIMEOUT; + + if (wait_for_transition && (orig_transition_tmo != h->transition_tmo)) { + sdev_printk(KERN_INFO, sdev, + "%s: transition timeout set to %d seconds\n", + ALUA_DH_NAME, h->transition_tmo); + expiry = jiffies + h->transition_tmo * HZ; + } + + if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR) + tpg_desc_tbl_off = 8; + else + tpg_desc_tbl_off = 4; + + for (k = tpg_desc_tbl_off, ucp = h->buff + tpg_desc_tbl_off; + 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', @@ -572,19 +638,23 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) switch (h->state) { case TPGS_STATE_TRANSITIONING: - if (time_before(jiffies, expiry)) { - /* State transition, retry */ - interval *= 2; - msleep(interval); - goto retry; + if (wait_for_transition) { + if (time_before(jiffies, expiry)) { + /* State transition, retry */ + interval += 2000; + msleep(interval); + goto retry; + } + err = SCSI_DH_RETRY; + } else { + err = SCSI_DH_OK; } + /* 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 unusable for unavailable/offline */ + /* Path unusable */ err = SCSI_DH_DEV_OFFLINED; break; default: @@ -614,13 +684,48 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) if (err != SCSI_DH_OK) goto out; - err = alua_rtpg(sdev, h); + err = alua_rtpg(sdev, h, 0); if (err != SCSI_DH_OK) goto out; out: return err; } +/* + * alua_set_params - set/unset the optimize flag + * @sdev: device on the path to be activated + * params - parameters in the following format + * "no_of_params\0param1\0param2\0param3\0...\0" + * For example, to set the flag pass the following parameters + * from multipath.conf + * hardware_handler "2 alua 1" + */ +static int alua_set_params(struct scsi_device *sdev, const char *params) +{ + struct alua_dh_data *h = get_alua_data(sdev); + unsigned int optimize = 0, argc; + const char *p = params; + int result = SCSI_DH_OK; + + if ((sscanf(params, "%u", &argc) != 1) || (argc != 1)) + return -EINVAL; + + while (*p++) + ; + if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1)) + return -EINVAL; + + if (optimize) + h->flags |= ALUA_OPTIMIZE_STPG; + else + h->flags &= ~ALUA_OPTIMIZE_STPG; + + return result; +} + +static uint optimize_stpg; +module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR); +MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than sending a STPG, when implicit TPGS is supported (0=No,1=Yes). Default is 0."); /* * alua_activate - activate a path @@ -637,14 +742,40 @@ static int alua_activate(struct scsi_device *sdev, { struct alua_dh_data *h = get_alua_data(sdev); int err = SCSI_DH_OK; + int stpg = 0; - err = alua_rtpg(sdev, h); + err = alua_rtpg(sdev, h, 1); if (err != SCSI_DH_OK) goto out; - if (h->tpgs & TPGS_MODE_EXPLICIT && - h->state != TPGS_STATE_OPTIMIZED && - h->state != TPGS_STATE_LBA_DEPENDENT) { + if (optimize_stpg) + h->flags |= ALUA_OPTIMIZE_STPG; + + if (h->tpgs & TPGS_MODE_EXPLICIT) { + switch (h->state) { + case TPGS_STATE_NONOPTIMIZED: + stpg = 1; + if ((h->flags & ALUA_OPTIMIZE_STPG) && + (!h->pref) && + (h->tpgs & TPGS_MODE_IMPLICIT)) + stpg = 0; + break; + case TPGS_STATE_STANDBY: + case TPGS_STATE_UNAVAILABLE: + stpg = 1; + break; + case TPGS_STATE_OFFLINE: + err = SCSI_DH_IO; + break; + case TPGS_STATE_TRANSITIONING: + err = SCSI_DH_RETRY; + break; + default: + break; + } + } + + if (stpg) { h->callback_fn = fn; h->callback_data = data; err = submit_stpg(h); @@ -698,6 +829,7 @@ static struct scsi_device_handler alua_dh = { .prep_fn = alua_prep_fn, .check_sense = alua_check_sense, .activate = alua_activate, + .set_params = alua_set_params, .match = alua_match, }; |