From 43394c67f8d6bb2f452ac25332ca0b271b344d81 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Fri, 19 Feb 2016 09:17:04 +0100 Subject: [PATCH] scsi_dh_alua: Use separate alua_port_group structure The port group needs to be a separate structure as several LUNs might belong to the same group. Reviewed-by: Christoph Hellwig Reviewed-by: Ewan Milne Signed-off-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- drivers/scsi/device_handler/scsi_dh_alua.c | 181 +++++++++++++++------ include/scsi/scsi_dh.h | 1 + 2 files changed, 129 insertions(+), 53 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index af5acc133f72..e9fb76000750 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -64,14 +64,24 @@ #define ALUA_OPTIMIZE_STPG 1 #define ALUA_RTPG_EXT_HDR_UNSUPP 2 -struct alua_dh_data { +static LIST_HEAD(port_group_list); +static DEFINE_SPINLOCK(port_group_lock); + +struct alua_port_group { + struct kref kref; + struct list_head node; int group_id; - int rel_port; int tpgs; int state; int pref; unsigned flags; /* used for optimizing STPG */ unsigned char transition_tmo; +}; + +struct alua_dh_data { + struct alua_port_group *pg; + int group_id; + int rel_port; struct scsi_device *sdev; activate_complete callback_fn; void *callback_data; @@ -82,6 +92,17 @@ struct alua_dh_data { static char print_alua_state(int); +static void release_port_group(struct kref *kref) +{ + struct alua_port_group *pg; + + pg = container_of(kref, struct alua_port_group, kref); + spin_lock(&port_group_lock); + list_del(&pg->node); + spin_unlock(&port_group_lock); + kfree(pg); +} + /* * submit_rtpg - Issue a REPORT TARGET GROUP STATES command * @sdev: sdev the command should be sent to @@ -141,6 +162,35 @@ static int submit_stpg(struct scsi_device *sdev, int group_id, ALUA_FAILOVER_RETRIES, NULL, req_flags); } +/* + * alua_alloc_pg - Allocate a new port_group structure + * @sdev: scsi device + * @h: alua device_handler data + * @group_id: port group id + * + * Allocate a new port_group structure for a given + * device. + */ +struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev, + int group_id, int tpgs) +{ + struct alua_port_group *pg; + + pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL); + if (!pg) + return NULL; + + pg->group_id = group_id; + pg->tpgs = tpgs; + pg->state = TPGS_STATE_OPTIMIZED; + kref_init(&pg->kref); + spin_lock(&port_group_lock); + list_add(&pg->node, &port_group_list); + spin_unlock(&port_group_lock); + + return pg; +} + /* * alua_check_tpgs - Evaluate TPGS setting * @sdev: device to be checked @@ -216,7 +266,6 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h) ALUA_DH_NAME); return SCSI_DH_DEV_UNSUPP; } - h->state = TPGS_STATE_OPTIMIZED; h->group_id = group_id; sdev_printk(KERN_INFO, sdev, @@ -312,7 +361,7 @@ static int alua_check_sense(struct scsi_device *sdev, * 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, int wait_for_transition) +static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int wait_for_transition) { struct scsi_sense_hdr sense_hdr; int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE; @@ -322,17 +371,17 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ unsigned int tpg_desc_tbl_off; unsigned char orig_transition_tmo; - if (!h->transition_tmo) + if (!pg->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 + pg->transition_tmo * HZ); buff = kzalloc(bufflen, GFP_KERNEL); if (!buff) return SCSI_DH_DEV_TEMP_BUSY; retry: - retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, h->flags); + retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, pg->flags); if (retval) { if (!scsi_sense_valid(&sense_hdr)) { @@ -353,10 +402,10 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ * The retry without rtpg_ext_hdr_req set * handles this. */ - if (!(h->flags & ALUA_RTPG_EXT_HDR_UNSUPP) && + if (!(pg->flags & ALUA_RTPG_EXT_HDR_UNSUPP) && sense_hdr.sense_key == ILLEGAL_REQUEST && sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) { - h->flags |= ALUA_RTPG_EXT_HDR_UNSUPP; + pg->flags |= ALUA_RTPG_EXT_HDR_UNSUPP; goto retry; } /* @@ -397,18 +446,18 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ goto retry; } - orig_transition_tmo = h->transition_tmo; + orig_transition_tmo = pg->transition_tmo; if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0) - h->transition_tmo = buff[5]; + pg->transition_tmo = buff[5]; else - h->transition_tmo = ALUA_FAILOVER_TIMEOUT; + pg->transition_tmo = ALUA_FAILOVER_TIMEOUT; if (wait_for_transition && - (orig_transition_tmo != h->transition_tmo)) { + (orig_transition_tmo != pg->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; + ALUA_DH_NAME, pg->transition_tmo); + expiry = jiffies + pg->transition_tmo * HZ; } if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR) @@ -420,9 +469,9 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ k < len; k += off, ucp += off) { - if (h->group_id == get_unaligned_be16(&ucp[2])) { - h->state = ucp[0] & 0x0f; - h->pref = ucp[0] >> 7; + if (pg->group_id == get_unaligned_be16(&ucp[2])) { + pg->state = ucp[0] & 0x0f; + pg->pref = ucp[0] >> 7; valid_states = ucp[1]; } off = 8 + (ucp[7] * 4); @@ -430,8 +479,8 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ sdev_printk(KERN_INFO, sdev, "%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", + ALUA_DH_NAME, pg->group_id, print_alua_state(pg->state), + pg->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', @@ -440,7 +489,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); - switch (h->state) { + switch (pg->state) { case TPGS_STATE_TRANSITIONING: if (wait_for_transition) { if (time_before(jiffies, expiry)) { @@ -455,7 +504,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ } /* Transitioning time exceeded, set port to standby */ - h->state = TPGS_STATE_STANDBY; + pg->state = TPGS_STATE_STANDBY; break; case TPGS_STATE_OFFLINE: /* Path unusable */ @@ -478,22 +527,22 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ * a re-evaluation of the target group state or SCSI_DH_OK * if no further action needs to be taken. */ -static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) +static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg) { int retval; struct scsi_sense_hdr sense_hdr; - if (!(h->tpgs & TPGS_MODE_EXPLICIT)) { + if (!(pg->tpgs & TPGS_MODE_EXPLICIT)) { /* Only implicit ALUA supported, retry */ return SCSI_DH_RETRY; } - switch (h->state) { + switch (pg->state) { case TPGS_STATE_OPTIMIZED: return SCSI_DH_OK; case TPGS_STATE_NONOPTIMIZED: - if ((h->flags & ALUA_OPTIMIZE_STPG) && - !h->pref && - (h->tpgs & TPGS_MODE_IMPLICIT)) + if ((pg->flags & ALUA_OPTIMIZE_STPG) && + !pg->pref && + (pg->tpgs & TPGS_MODE_IMPLICIT)) return SCSI_DH_OK; break; case TPGS_STATE_STANDBY: @@ -506,10 +555,10 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) default: sdev_printk(KERN_INFO, sdev, "%s: stpg failed, unhandled TPGS state %d", - ALUA_DH_NAME, h->state); + ALUA_DH_NAME, pg->state); return SCSI_DH_NOSYS; } - retval = submit_stpg(sdev, h->group_id, &sense_hdr); + retval = submit_stpg(sdev, pg->group_id, &sense_hdr); if (retval) { if (!scsi_sense_valid(&sense_hdr)) { @@ -519,7 +568,7 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) if (driver_byte(retval) == DRIVER_ERROR) return SCSI_DH_DEV_TEMP_BUSY; } else { - sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n", + sdev_printk(KERN_INFO, sdev, "%s: stpg failed\n", ALUA_DH_NAME); scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); } @@ -537,20 +586,24 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) */ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) { - int err = SCSI_DH_DEV_UNSUPP; + int err = SCSI_DH_DEV_UNSUPP, tpgs; - h->tpgs = alua_check_tpgs(sdev); - if (h->tpgs == TPGS_MODE_NONE) + tpgs = alua_check_tpgs(sdev); + if (tpgs == TPGS_MODE_NONE) goto out; err = alua_check_vpd(sdev, h); if (err != SCSI_DH_OK) goto out; - err = alua_rtpg(sdev, h, 0); - if (err != SCSI_DH_OK) + h->pg = alua_alloc_pg(sdev, h->group_id, tpgs); + if (!h->pg) { + err = SCSI_DH_NOMEM; goto out; - + } + kref_get(&h->pg->kref); + err = alua_rtpg(sdev, h->pg, 0); + kref_put(&h->pg->kref, release_port_group); out: return err; } @@ -566,6 +619,7 @@ out: static int alua_set_params(struct scsi_device *sdev, const char *params) { struct alua_dh_data *h = sdev->handler_data; + struct alua_port_group *pg = NULL; unsigned int optimize = 0, argc; const char *p = params; int result = SCSI_DH_OK; @@ -578,10 +632,14 @@ static int alua_set_params(struct scsi_device *sdev, const char *params) if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1)) return -EINVAL; + pg = h->pg; + if (!pg) + return -ENXIO; + if (optimize) - h->flags |= ALUA_OPTIMIZE_STPG; + pg->flags |= ALUA_OPTIMIZE_STPG; else - h->flags &= ~ALUA_OPTIMIZE_STPG; + pg->flags &= ~ALUA_OPTIMIZE_STPG; return result; } @@ -606,16 +664,23 @@ static int alua_activate(struct scsi_device *sdev, struct alua_dh_data *h = sdev->handler_data; int err = SCSI_DH_OK; - err = alua_rtpg(sdev, h, 1); - if (err != SCSI_DH_OK) + if (!h->pg) goto out; + kref_get(&h->pg->kref); + if (optimize_stpg) - h->flags |= ALUA_OPTIMIZE_STPG; + h->pg->flags |= ALUA_OPTIMIZE_STPG; - err = alua_stpg(sdev, h); + err = alua_rtpg(sdev, h->pg, 1); + if (err != SCSI_DH_OK) { + kref_put(&h->pg->kref, release_port_group); + goto out; + } + err = alua_stpg(sdev, h->pg); if (err == SCSI_DH_RETRY) - err = alua_rtpg(sdev, h, 1); + err = alua_rtpg(sdev, h->pg, 1); + kref_put(&h->pg->kref, release_port_group); out: if (fn) fn(data, err); @@ -631,13 +696,19 @@ out: static int alua_prep_fn(struct scsi_device *sdev, struct request *req) { struct alua_dh_data *h = sdev->handler_data; + int state; int ret = BLKPREP_OK; - if (h->state == TPGS_STATE_TRANSITIONING) + if (!h->pg) + return ret; + kref_get(&h->pg->kref); + state = h->pg->state; + kref_put(&h->pg->kref, release_port_group); + if (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) { + else if (state != TPGS_STATE_OPTIMIZED && + state != TPGS_STATE_NONOPTIMIZED && + state != TPGS_STATE_LBA_DEPENDENT) { ret = BLKPREP_KILL; req->cmd_flags |= REQ_QUIET; } @@ -652,18 +723,18 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req) static int alua_bus_attach(struct scsi_device *sdev) { struct alua_dh_data *h; - int err; + int err, ret = -EINVAL; h = kzalloc(sizeof(*h) , GFP_KERNEL); if (!h) return -ENOMEM; - h->tpgs = TPGS_MODE_UNINITIALIZED; - h->state = TPGS_STATE_OPTIMIZED; - h->group_id = -1; + h->pg = NULL; h->rel_port = -1; h->sdev = sdev; err = alua_initialize(sdev, h); + if (err == SCSI_DH_NOMEM) + ret = -ENOMEM; if (err != SCSI_DH_OK && err != SCSI_DH_DEV_OFFLINED) goto failed; @@ -671,7 +742,7 @@ static int alua_bus_attach(struct scsi_device *sdev) return 0; failed: kfree(h); - return -EINVAL; + return ret; } /* @@ -682,6 +753,10 @@ static void alua_bus_detach(struct scsi_device *sdev) { struct alua_dh_data *h = sdev->handler_data; + if (h->pg) { + kref_put(&h->pg->kref, release_port_group); + h->pg = NULL; + } sdev->handler_data = NULL; kfree(h); } diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h index 85d731746834..7e184c6ebe5e 100644 --- a/include/scsi/scsi_dh.h +++ b/include/scsi/scsi_dh.h @@ -52,6 +52,7 @@ enum { SCSI_DH_TIMED_OUT, SCSI_DH_RES_TEMP_UNAVAIL, SCSI_DH_DEV_OFFLINED, + SCSI_DH_NOMEM, SCSI_DH_NOSYS, SCSI_DH_DRIVER_MAX, }; -- 2.39.5