From: Stefan Weinhuber Date: Wed, 5 Jan 2011 11:48:04 +0000 (+0100) Subject: [S390] dasd: Improve handling of stolen DASD reservation X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=5a27e60dec59a95bd7f8ae9a19ae2ede4f76395b;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git [S390] dasd: Improve handling of stolen DASD reservation If a DASD device has been reserved by a Linux system, and later this reservation is ‘stolen’ by a second system by means of an unconditional reserve, then the first system receives a notification about this fact. With this patch such an event can be either ignored, as before, or it can be used to let the device fail all I/O request, so that the device will not block anymore. Signed-off-by: Stefan Weinhuber Signed-off-by: Martin Schwidefsky --- diff --git a/arch/s390/include/asm/dasd.h b/arch/s390/include/asm/dasd.h index b604a9186f8e..47fcdada5d25 100644 --- a/arch/s390/include/asm/dasd.h +++ b/arch/s390/include/asm/dasd.h @@ -80,6 +80,7 @@ typedef struct dasd_information2_t { #define DASD_FEATURE_INITIAL_ONLINE 0x04 #define DASD_FEATURE_ERPLOG 0x08 #define DASD_FEATURE_FAILFAST 0x10 +#define DASD_FEATURE_FAILONSLCK 0x20 #define DASD_PARTN_BITS 2 diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 8f2067bc88c0..f16afe74464f 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -902,6 +902,16 @@ int dasd_start_IO(struct dasd_ccw_req *cqr) return rc; } device = (struct dasd_device *) cqr->startdev; + if (((cqr->block && + test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) || + test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) && + !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { + DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p " + "because of stolen lock", cqr); + cqr->status = DASD_CQR_ERROR; + cqr->intrc = -EPERM; + return -EPERM; + } if (cqr->retries < 0) { /* internal error 14 - start_IO run out of retries */ sprintf(errorstring, "14 %p", cqr); @@ -1115,16 +1125,11 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, } now = get_clock(); - - /* check for unsolicited interrupts */ cqr = (struct dasd_ccw_req *) intparm; - if (!cqr || ((scsw_cc(&irb->scsw) == 1) && - (scsw_fctl(&irb->scsw) & SCSW_FCTL_START_FUNC) && - ((scsw_stctl(&irb->scsw) == SCSW_STCTL_STATUS_PEND) || - (scsw_stctl(&irb->scsw) == (SCSW_STCTL_STATUS_PEND | - SCSW_STCTL_ALERT_STATUS))))) { - if (cqr && cqr->status == DASD_CQR_IN_IO) - cqr->status = DASD_CQR_QUEUED; + /* check for conditions that should be handled immediately */ + if (!cqr || + !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) && + scsw_cstat(&irb->scsw) == 0)) { if (cqr) memcpy(&cqr->irb, irb, sizeof(*irb)); device = dasd_device_from_cdev_locked(cdev); @@ -1135,17 +1140,14 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, dasd_put_device(device); return; } - device->discipline->dump_sense_dbf(device, irb, - "unsolicited"); - if ((device->features & DASD_FEATURE_ERPLOG)) - device->discipline->dump_sense(device, cqr, - irb); - dasd_device_clear_timer(device); - device->discipline->handle_unsolicited_interrupt(device, - irb); + device->discipline->dump_sense_dbf(device, irb, "int"); + if (device->features & DASD_FEATURE_ERPLOG) + device->discipline->dump_sense(device, cqr, irb); + device->discipline->check_for_device_change(device, cqr, irb); dasd_put_device(device); - return; } + if (!cqr) + return; device = (struct dasd_device *) cqr->startdev; if (!device || @@ -1185,13 +1187,6 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, struct dasd_ccw_req, devlist); } } else { /* error */ - memcpy(&cqr->irb, irb, sizeof(struct irb)); - /* log sense for every failed I/O to s390 debugfeature */ - dasd_log_sense_dbf(cqr, irb); - if (device->features & DASD_FEATURE_ERPLOG) { - dasd_log_sense(cqr, irb); - } - /* * If we don't want complex ERP for this request, then just * reset this and retry it in the fastpath @@ -1232,13 +1227,13 @@ enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb) goto out; if (test_bit(DASD_FLAG_OFFLINE, &device->flags) || device->state != device->target || - !device->discipline->handle_unsolicited_interrupt){ + !device->discipline->check_for_device_change){ dasd_put_device(device); goto out; } - - dasd_device_clear_timer(device); - device->discipline->handle_unsolicited_interrupt(device, irb); + if (device->discipline->dump_sense_dbf) + device->discipline->dump_sense_dbf(device, irb, "uc"); + device->discipline->check_for_device_change(device, NULL, irb); dasd_put_device(device); out: return UC_TODO_RETRY; @@ -1659,7 +1654,12 @@ static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible) continue; if (cqr->status != DASD_CQR_FILLED) /* could be failed */ continue; - + if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && + !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { + cqr->status = DASD_CQR_FAILED; + cqr->intrc = -EPERM; + continue; + } /* Non-temporary stop condition will trigger fail fast */ if (device->stopped & ~DASD_STOPPED_PENDING && test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && @@ -1667,7 +1667,6 @@ static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible) cqr->status = DASD_CQR_FAILED; continue; } - /* Don't try to start requests if device is stopped */ if (interruptible) { rc = wait_event_interruptible( @@ -1752,13 +1751,18 @@ int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr) int rc; device = cqr->startdev; + if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && + !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { + cqr->status = DASD_CQR_FAILED; + cqr->intrc = -EPERM; + return -EIO; + } spin_lock_irq(get_ccwdev_lock(device->cdev)); rc = _dasd_term_running_cqr(device); if (rc) { spin_unlock_irq(get_ccwdev_lock(device->cdev)); return rc; } - cqr->callback = dasd_wakeup_cb; cqr->callback_data = DASD_SLEEPON_START_TAG; cqr->status = DASD_CQR_QUEUED; @@ -2062,6 +2066,13 @@ static void __dasd_block_start_head(struct dasd_block *block) list_for_each_entry(cqr, &block->ccw_queue, blocklist) { if (cqr->status != DASD_CQR_FILLED) continue; + if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) && + !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { + cqr->status = DASD_CQR_FAILED; + cqr->intrc = -EPERM; + dasd_schedule_block_bh(block); + continue; + } /* Non-temporary stop condition will trigger fail fast */ if (block->base->stopped & ~DASD_STOPPED_PENDING && test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index 0001df8ad3e6..47fc88692494 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -1127,6 +1127,103 @@ dasd_expires_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store); +static ssize_t dasd_reservation_policy_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct dasd_devmap *devmap; + int rc = 0; + + devmap = dasd_find_busid(dev_name(dev)); + if (IS_ERR(devmap)) { + rc = snprintf(buf, PAGE_SIZE, "ignore\n"); + } else { + spin_lock(&dasd_devmap_lock); + if (devmap->features & DASD_FEATURE_FAILONSLCK) + rc = snprintf(buf, PAGE_SIZE, "fail\n"); + else + rc = snprintf(buf, PAGE_SIZE, "ignore\n"); + spin_unlock(&dasd_devmap_lock); + } + return rc; +} + +static ssize_t dasd_reservation_policy_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct dasd_devmap *devmap; + int rc; + + devmap = dasd_devmap_from_cdev(to_ccwdev(dev)); + if (IS_ERR(devmap)) + return PTR_ERR(devmap); + rc = 0; + spin_lock(&dasd_devmap_lock); + if (sysfs_streq("ignore", buf)) + devmap->features &= ~DASD_FEATURE_FAILONSLCK; + else if (sysfs_streq("fail", buf)) + devmap->features |= DASD_FEATURE_FAILONSLCK; + else + rc = -EINVAL; + if (devmap->device) + devmap->device->features = devmap->features; + spin_unlock(&dasd_devmap_lock); + if (rc) + return rc; + else + return count; +} + +static DEVICE_ATTR(reservation_policy, 0644, + dasd_reservation_policy_show, dasd_reservation_policy_store); + +static ssize_t dasd_reservation_state_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct dasd_device *device; + int rc = 0; + + device = dasd_device_from_cdev(to_ccwdev(dev)); + if (IS_ERR(device)) + return snprintf(buf, PAGE_SIZE, "none\n"); + + if (test_bit(DASD_FLAG_IS_RESERVED, &device->flags)) + rc = snprintf(buf, PAGE_SIZE, "reserved\n"); + else if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) + rc = snprintf(buf, PAGE_SIZE, "lost\n"); + else + rc = snprintf(buf, PAGE_SIZE, "none\n"); + dasd_put_device(device); + return rc; +} + +static ssize_t dasd_reservation_state_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct dasd_device *device; + int rc = 0; + + device = dasd_device_from_cdev(to_ccwdev(dev)); + if (IS_ERR(device)) + return -ENODEV; + if (sysfs_streq("reset", buf)) + clear_bit(DASD_FLAG_LOCK_STOLEN, &device->flags); + else + rc = -EINVAL; + dasd_put_device(device); + + if (rc) + return rc; + else + return count; +} + +static DEVICE_ATTR(last_known_reservation_state, 0644, + dasd_reservation_state_show, dasd_reservation_state_store); + static struct attribute * dasd_attrs[] = { &dev_attr_readonly.attr, &dev_attr_discipline.attr, @@ -1139,6 +1236,8 @@ static struct attribute * dasd_attrs[] = { &dev_attr_erplog.attr, &dev_attr_failfast.attr, &dev_attr_expires.attr, + &dev_attr_reservation_policy.attr, + &dev_attr_last_known_reservation_state.attr, NULL, }; diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index a1ebf5722ae5..46eafce3a0a6 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -817,6 +817,7 @@ static int dasd_eckd_read_conf_immediately(struct dasd_device *device, dasd_eckd_fill_rcd_cqr(device, cqr, rcd_buffer, lpm); clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); + set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags); cqr->retries = 5; rc = dasd_sleep_on_immediatly(cqr); return rc; @@ -1947,9 +1948,9 @@ dasd_eckd_erp_postaction(struct dasd_ccw_req * cqr) return dasd_default_erp_postaction; } - -static void dasd_eckd_handle_unsolicited_interrupt(struct dasd_device *device, - struct irb *irb) +static void dasd_eckd_check_for_device_change(struct dasd_device *device, + struct dasd_ccw_req *cqr, + struct irb *irb) { char mask; char *sense = NULL; @@ -1973,40 +1974,41 @@ static void dasd_eckd_handle_unsolicited_interrupt(struct dasd_device *device, /* schedule worker to reload device */ dasd_reload_device(device); } - dasd_generic_handle_state_change(device); return; } - /* summary unit check */ sense = dasd_get_sense(irb); - if (sense && (sense[7] == 0x0D) && + if (!sense) + return; + + /* summary unit check */ + if ((sense[7] == 0x0D) && (scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK)) { dasd_alias_handle_summary_unit_check(device, irb); return; } /* service information message SIM */ - if (sense && !(sense[27] & DASD_SENSE_BIT_0) && + if (!cqr && !(sense[27] & DASD_SENSE_BIT_0) && ((sense[6] & DASD_SIM_SENSE) == DASD_SIM_SENSE)) { dasd_3990_erp_handle_sim(device, sense); - dasd_schedule_device_bh(device); return; } - if ((scsw_cc(&irb->scsw) == 1) && !sense && - (scsw_fctl(&irb->scsw) == SCSW_FCTL_START_FUNC) && - (scsw_actl(&irb->scsw) == SCSW_ACTL_START_PEND) && - (scsw_stctl(&irb->scsw) == SCSW_STCTL_STATUS_PEND)) { - /* fake irb do nothing, they are handled elsewhere */ - dasd_schedule_device_bh(device); - return; + /* loss of device reservation is handled via base devices only + * as alias devices may be used with several bases + */ + if (device->block && (sense[7] == 0x3F) && + (scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) && + test_bit(DASD_FLAG_IS_RESERVED, &device->flags)) { + if (device->features & DASD_FEATURE_FAILONSLCK) + set_bit(DASD_FLAG_LOCK_STOLEN, &device->flags); + clear_bit(DASD_FLAG_IS_RESERVED, &device->flags); + dev_err(&device->cdev->dev, + "The device reservation was lost\n"); } - - dasd_schedule_device_bh(device); - return; -}; - +} static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single( struct dasd_device *startdev, @@ -2931,6 +2933,8 @@ dasd_eckd_release(struct dasd_device *device) cqr->status = DASD_CQR_FILLED; rc = dasd_sleep_on_immediatly(cqr); + if (!rc) + clear_bit(DASD_FLAG_IS_RESERVED, &device->flags); if (useglobal) mutex_unlock(&dasd_reserve_mutex); @@ -2984,6 +2988,8 @@ dasd_eckd_reserve(struct dasd_device *device) cqr->status = DASD_CQR_FILLED; rc = dasd_sleep_on_immediatly(cqr); + if (!rc) + set_bit(DASD_FLAG_IS_RESERVED, &device->flags); if (useglobal) mutex_unlock(&dasd_reserve_mutex); @@ -3036,6 +3042,8 @@ dasd_eckd_steal_lock(struct dasd_device *device) cqr->status = DASD_CQR_FILLED; rc = dasd_sleep_on_immediatly(cqr); + if (!rc) + set_bit(DASD_FLAG_IS_RESERVED, &device->flags); if (useglobal) mutex_unlock(&dasd_reserve_mutex); @@ -3088,6 +3096,7 @@ static int dasd_eckd_snid(struct dasd_device *device, cqr->memdev = device; clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); + set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags); cqr->retries = 5; cqr->expires = 10 * HZ; cqr->buildclk = get_clock(); @@ -3832,7 +3841,7 @@ static struct dasd_discipline dasd_eckd_discipline = { .format_device = dasd_eckd_format_device, .erp_action = dasd_eckd_erp_action, .erp_postaction = dasd_eckd_erp_postaction, - .handle_unsolicited_interrupt = dasd_eckd_handle_unsolicited_interrupt, + .check_for_device_change = dasd_eckd_check_for_device_change, .build_cp = dasd_eckd_build_alias_cp, .free_cp = dasd_eckd_free_alias_cp, .dump_sense = dasd_eckd_dump_sense, diff --git a/drivers/s390/block/dasd_eer.c b/drivers/s390/block/dasd_eer.c index 83b4615a3b62..77f778b7b070 100644 --- a/drivers/s390/block/dasd_eer.c +++ b/drivers/s390/block/dasd_eer.c @@ -473,6 +473,7 @@ int dasd_eer_enable(struct dasd_device *device) cqr->retries = 255; cqr->expires = 10 * HZ; clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); + set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags); ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_SNSS; diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c index 86bacda2c5f6..be89b3a893da 100644 --- a/drivers/s390/block/dasd_fba.c +++ b/drivers/s390/block/dasd_fba.c @@ -233,24 +233,16 @@ dasd_fba_erp_postaction(struct dasd_ccw_req * cqr) return NULL; } -static void dasd_fba_handle_unsolicited_interrupt(struct dasd_device *device, - struct irb *irb) +static void dasd_fba_check_for_device_change(struct dasd_device *device, + struct dasd_ccw_req *cqr, + struct irb *irb) { char mask; /* first of all check for state change pending interrupt */ mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP; - if ((irb->scsw.cmd.dstat & mask) == mask) { + if ((irb->scsw.cmd.dstat & mask) == mask) dasd_generic_handle_state_change(device); - return; - } - - /* check for unsolicited interrupts */ - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "unsolicited interrupt received"); - device->discipline->dump_sense_dbf(device, irb, "unsolicited"); - dasd_schedule_device_bh(device); - return; }; static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev, @@ -605,7 +597,7 @@ static struct dasd_discipline dasd_fba_discipline = { .handle_terminated_request = dasd_fba_handle_terminated_request, .erp_action = dasd_fba_erp_action, .erp_postaction = dasd_fba_erp_postaction, - .handle_unsolicited_interrupt = dasd_fba_handle_unsolicited_interrupt, + .check_for_device_change = dasd_fba_check_for_device_change, .build_cp = dasd_fba_build_cp, .free_cp = dasd_fba_free_cp, .dump_sense = dasd_fba_dump_sense, diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h index ba038ef57606..df9f6999411d 100644 --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -232,6 +232,10 @@ struct dasd_ccw_req { #define DASD_CQR_FLAGS_USE_ERP 0 /* use ERP for this request */ #define DASD_CQR_FLAGS_FAILFAST 1 /* FAILFAST */ #define DASD_CQR_VERIFY_PATH 2 /* path verification request */ +#define DASD_CQR_ALLOW_SLOCK 3 /* Try this request even when lock was + * stolen. Should not be combined with + * DASD_CQR_FLAGS_USE_ERP + */ /* Signature for error recovery functions. */ typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *); @@ -334,9 +338,9 @@ struct dasd_discipline { void (*dump_sense) (struct dasd_device *, struct dasd_ccw_req *, struct irb *); void (*dump_sense_dbf) (struct dasd_device *, struct irb *, char *); - - void (*handle_unsolicited_interrupt) (struct dasd_device *, - struct irb *); + void (*check_for_device_change) (struct dasd_device *, + struct dasd_ccw_req *, + struct irb *); /* i/o control functions. */ int (*fill_geometry) (struct dasd_block *, struct hd_geometry *); @@ -473,6 +477,9 @@ struct dasd_block { * confuse this with the user specified * read-only feature. */ +#define DASD_FLAG_IS_RESERVED 7 /* The device is reserved */ +#define DASD_FLAG_LOCK_STOLEN 8 /* The device lock was stolen */ + void dasd_put_device_wake(struct dasd_device *);