From 020bf042e5b397479c1174081b935d0ff15d1a64 Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Tue, 15 Dec 2015 10:16:43 +0100 Subject: s390/dasd: prevent incorrect length error under z/VM after PAV changes The channel checks the specified length and the provided amount of data for CCWs and provides an incorrect length error if the size does not match. Under z/VM with simulation activated the length may get changed. Having the suppress length indication bit set is stated as good CCW coding practice and avoids errors under z/VM. Cc: stable@vger.kernel.org Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd_alias.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/s390/block/dasd_alias.c b/drivers/s390/block/dasd_alias.c index 184b1dbeb554..4ff914c0f13c 100644 --- a/drivers/s390/block/dasd_alias.c +++ b/drivers/s390/block/dasd_alias.c @@ -723,7 +723,7 @@ static int reset_summary_unit_check(struct alias_lcu *lcu, ASCEBC((char *) &cqr->magic, 4); ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_RSCK; - ccw->flags = 0 ; + ccw->flags = CCW_FLAG_SLI; ccw->count = 16; ccw->cda = (__u32)(addr_t) cqr->data; ((char *)cqr->data)[0] = reason; -- cgit v1.2.3 From 9d862ababb609439c5d6987f6d3ddd09e703aa0b Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Tue, 15 Dec 2015 10:45:05 +0100 Subject: s390/dasd: fix refcount for PAV reassignment Add refcount to the DASD device when a summary unit check worker is scheduled. This prevents that the device is set offline with worker in place. Cc: stable@vger.kernel.org Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd_alias.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'drivers') diff --git a/drivers/s390/block/dasd_alias.c b/drivers/s390/block/dasd_alias.c index 4ff914c0f13c..286782c60da4 100644 --- a/drivers/s390/block/dasd_alias.c +++ b/drivers/s390/block/dasd_alias.c @@ -264,8 +264,10 @@ void dasd_alias_disconnect_device_from_lcu(struct dasd_device *device) spin_unlock_irqrestore(&lcu->lock, flags); cancel_work_sync(&lcu->suc_data.worker); spin_lock_irqsave(&lcu->lock, flags); - if (device == lcu->suc_data.device) + if (device == lcu->suc_data.device) { + dasd_put_device(device); lcu->suc_data.device = NULL; + } } was_pending = 0; if (device == lcu->ruac_data.device) { @@ -273,8 +275,10 @@ void dasd_alias_disconnect_device_from_lcu(struct dasd_device *device) was_pending = 1; cancel_delayed_work_sync(&lcu->ruac_data.dwork); spin_lock_irqsave(&lcu->lock, flags); - if (device == lcu->ruac_data.device) + if (device == lcu->ruac_data.device) { + dasd_put_device(device); lcu->ruac_data.device = NULL; + } } private->lcu = NULL; spin_unlock_irqrestore(&lcu->lock, flags); @@ -549,8 +553,10 @@ static void lcu_update_work(struct work_struct *work) if ((rc && (rc != -EOPNOTSUPP)) || (lcu->flags & NEED_UAC_UPDATE)) { DBF_DEV_EVENT(DBF_WARNING, device, "could not update" " alias data in lcu (rc = %d), retry later", rc); - schedule_delayed_work(&lcu->ruac_data.dwork, 30*HZ); + if (!schedule_delayed_work(&lcu->ruac_data.dwork, 30*HZ)) + dasd_put_device(device); } else { + dasd_put_device(device); lcu->ruac_data.device = NULL; lcu->flags &= ~UPDATE_PENDING; } @@ -593,8 +599,10 @@ static int _schedule_lcu_update(struct alias_lcu *lcu, */ if (!usedev) return -EINVAL; + dasd_get_device(usedev); lcu->ruac_data.device = usedev; - schedule_delayed_work(&lcu->ruac_data.dwork, 0); + if (!schedule_delayed_work(&lcu->ruac_data.dwork, 0)) + dasd_put_device(usedev); return 0; } @@ -930,6 +938,7 @@ static void summary_unit_check_handling_work(struct work_struct *work) /* 3. read new alias configuration */ _schedule_lcu_update(lcu, device); lcu->suc_data.device = NULL; + dasd_put_device(device); spin_unlock_irqrestore(&lcu->lock, flags); } @@ -989,6 +998,8 @@ void dasd_alias_handle_summary_unit_check(struct dasd_device *device, } lcu->suc_data.reason = reason; lcu->suc_data.device = device; + dasd_get_device(device); spin_unlock(&lcu->lock); - schedule_work(&lcu->suc_data.worker); + if (!schedule_work(&lcu->suc_data.worker)) + dasd_put_device(device); }; -- cgit v1.2.3 From 12d319b920fa673a4d5e7c1785c5dc82dcd15257 Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Fri, 12 Feb 2016 14:50:52 +0100 Subject: s390/dasd: fix performance drop Commit ca369d51b ("sd: Fix device-imposed transfer length limits") introduced a new queue limit max_dev_sectors which limits the maximum sectors for requests. The default value leads to small dasd requests and therefor to a performance drop. Set the max_dev_sectors value to the same value as the max_hw_sectors to use the maximum available request size for DASD devices. Signed-off-by: Stefan Haberland Cc: stable@vger.kernel.org # 4.4+ Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers') diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 41605dac8309..c78db05e75b1 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -3035,6 +3035,7 @@ static void dasd_setup_queue(struct dasd_block *block) max = block->base->discipline->max_blocks << block->s2b_shift; } queue_flag_set_unlocked(QUEUE_FLAG_NONROT, block->request_queue); + block->request_queue->limits.max_dev_sectors = max; blk_queue_logical_block_size(block->request_queue, block->bp_block); blk_queue_max_hw_sectors(block->request_queue, max); -- cgit v1.2.3