From 3d71ad32167c9124d5621b54c37a74ef38aa93b0 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Wed, 30 Jan 2013 09:26:18 +0000 Subject: s390/dasd: Add 'timeout' attribute This patch adds a 'timeout' attibute to the DASD driver. When set to non-zero, the blk_timeout function will be enabled with the timeout specified in the attribute. Setting 'timeout' to '0' will disable block timeouts. Signed-off-by: Hannes Reinecke Signed-off-by: Stefan Weinhuber Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd.c | 2 ++ drivers/s390/block/dasd_devmap.c | 56 ++++++++++++++++++++++++++++++++++++++++ drivers/s390/block/dasd_int.h | 4 +++ 3 files changed, 62 insertions(+) (limited to 'drivers/s390') diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index b97624bf183..54f4bb8060c 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -2894,6 +2894,8 @@ enum blk_eh_timer_return dasd_times_out(struct request *req) return BLK_EH_NOT_HANDLED; device = cqr->startdev ? cqr->startdev : block->base; + if (!device->blk_timeout) + return BLK_EH_RESET_TIMER; DBF_DEV_EVENT(DBF_WARNING, device, " dasd_times_out cqr %p status %x", cqr, cqr->status); diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index bc3e7afac18..58bc6eb49de 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -1280,6 +1280,61 @@ dasd_retries_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR(retries, 0644, dasd_retries_show, dasd_retries_store); +static ssize_t +dasd_timeout_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct dasd_device *device; + int len; + + device = dasd_device_from_cdev(to_ccwdev(dev)); + if (IS_ERR(device)) + return -ENODEV; + len = snprintf(buf, PAGE_SIZE, "%lu\n", device->blk_timeout); + dasd_put_device(device); + return len; +} + +static ssize_t +dasd_timeout_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct dasd_device *device; + struct request_queue *q; + unsigned long val, flags; + + device = dasd_device_from_cdev(to_ccwdev(dev)); + if (IS_ERR(device) || !device->block) + return -ENODEV; + + if ((strict_strtoul(buf, 10, &val) != 0) || + val > UINT_MAX / HZ) { + dasd_put_device(device); + return -EINVAL; + } + q = device->block->request_queue; + if (!q) { + dasd_put_device(device); + return -ENODEV; + } + spin_lock_irqsave(&device->block->request_queue_lock, flags); + if (!val) + blk_queue_rq_timed_out(q, NULL); + else + blk_queue_rq_timed_out(q, dasd_times_out); + + device->blk_timeout = val; + + blk_queue_rq_timeout(q, device->blk_timeout * HZ); + spin_unlock_irqrestore(&device->block->request_queue_lock, flags); + + dasd_put_device(device); + return count; +} + +static DEVICE_ATTR(timeout, 0644, + dasd_timeout_show, dasd_timeout_store); + static ssize_t dasd_reservation_policy_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -1391,6 +1446,7 @@ static struct attribute * dasd_attrs[] = { &dev_attr_failfast.attr, &dev_attr_expires.attr, &dev_attr_retries.attr, + &dev_attr_timeout.attr, &dev_attr_reservation_policy.attr, &dev_attr_last_known_reservation_state.attr, &dev_attr_safe_offline.attr, diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h index ad42075868c..2bd03f45a72 100644 --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -470,6 +470,8 @@ struct dasd_device { unsigned long default_expires; unsigned long default_retries; + unsigned long blk_timeout; + struct dentry *debugfs_dentry; struct dasd_profile profile; }; @@ -663,6 +665,8 @@ void dasd_free_device(struct dasd_device *); struct dasd_block *dasd_alloc_block(void); void dasd_free_block(struct dasd_block *); +enum blk_eh_timer_return dasd_times_out(struct request *req); + void dasd_enable_device(struct dasd_device *); void dasd_set_target_state(struct dasd_device *, int); void dasd_kick_device(struct dasd_device *); -- cgit v1.2.3