From 5a27e60dec59a95bd7f8ae9a19ae2ede4f76395b Mon Sep 17 00:00:00 2001 From: Stefan Weinhuber Date: Wed, 5 Jan 2011 12:48:04 +0100 Subject: [S390] dasd: Improve handling of stolen DASD reservation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- drivers/s390/block/dasd_eckd.c | 51 +++++++++++++++++++++++++----------------- 1 file changed, 30 insertions(+), 21 deletions(-) (limited to 'drivers/s390/block/dasd_eckd.c') 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, -- cgit v1.2.3