X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=block%2Fblk-timeout.c;h=1ba7e0aca8781b55ce14fa54491da8f81505b747;hb=9e845abfc8a8973373821aa05302794fd254514b;hp=b36d07bf0afb965b2a90528606c09ecb920c45e7;hpb=242f9dcb8ba6f68fcd217a119a7648a4f69290e9;p=safe%2Fjmp%2Flinux-2.6 diff --git a/block/blk-timeout.c b/block/blk-timeout.c index b36d07bf..1ba7e0a 100644 --- a/block/blk-timeout.c +++ b/block/blk-timeout.c @@ -4,9 +4,68 @@ #include #include #include +#include #include "blk.h" +#ifdef CONFIG_FAIL_IO_TIMEOUT + +static DECLARE_FAULT_ATTR(fail_io_timeout); + +static int __init setup_fail_io_timeout(char *str) +{ + return setup_fault_attr(&fail_io_timeout, str); +} +__setup("fail_io_timeout=", setup_fail_io_timeout); + +int blk_should_fake_timeout(struct request_queue *q) +{ + if (!test_bit(QUEUE_FLAG_FAIL_IO, &q->queue_flags)) + return 0; + + return should_fail(&fail_io_timeout, 1); +} + +static int __init fail_io_timeout_debugfs(void) +{ + return init_fault_attr_dentries(&fail_io_timeout, "fail_io_timeout"); +} + +late_initcall(fail_io_timeout_debugfs); + +ssize_t part_timeout_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + int set = test_bit(QUEUE_FLAG_FAIL_IO, &disk->queue->queue_flags); + + return sprintf(buf, "%d\n", set != 0); +} + +ssize_t part_timeout_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct gendisk *disk = dev_to_disk(dev); + int val; + + if (count) { + struct request_queue *q = disk->queue; + char *p = (char *) buf; + + val = simple_strtoul(p, &p, 10); + spin_lock_irq(q->queue_lock); + if (val) + queue_flag_set(QUEUE_FLAG_FAIL_IO, q); + else + queue_flag_clear(QUEUE_FLAG_FAIL_IO, q); + spin_unlock_irq(q->queue_lock); + } + + return count; +} + +#endif /* CONFIG_FAIL_IO_TIMEOUT */ + /* * blk_delete_timer - Delete/cancel timer for a given function. * @req: request that we are canceling timer for @@ -14,18 +73,7 @@ */ void blk_delete_timer(struct request *req) { - struct request_queue *q = req->q; - - /* - * Nothing to detach - */ - if (!q->rq_timed_out_fn || !req->deadline) - return; - list_del_init(&req->timeout_list); - - if (list_empty(&q->timeout_list)) - del_timer(&q->timeout); } static void blk_rq_timed_out(struct request *req) @@ -59,7 +107,7 @@ static void blk_rq_timed_out(struct request *req) void blk_rq_timed_out_timer(unsigned long data) { struct request_queue *q = (struct request_queue *) data; - unsigned long flags, uninitialized_var(next), next_set = 0; + unsigned long flags, next = 0; struct request *rq, *tmp; spin_lock_irqsave(q->queue_lock, flags); @@ -74,16 +122,17 @@ void blk_rq_timed_out_timer(unsigned long data) if (blk_mark_rq_complete(rq)) continue; blk_rq_timed_out(rq); - } - if (!next_set) { - next = rq->deadline; - next_set = 1; - } else if (time_after(next, rq->deadline)) + } else if (!next || time_after(next, rq->deadline)) next = rq->deadline; } - if (next_set && !list_empty(&q->timeout_list)) - mod_timer(&q->timeout, round_jiffies(next)); + /* + * next can never be 0 here with the list non-empty, since we always + * bump ->deadline to 1 so we can detect if the timer was ever added + * or not. See comment in blk_add_timer() + */ + if (next) + mod_timer(&q->timeout, round_jiffies_up(next)); spin_unlock_irqrestore(q->queue_lock, flags); } @@ -99,6 +148,8 @@ void blk_rq_timed_out_timer(unsigned long data) */ void blk_abort_request(struct request *req) { + if (blk_mark_rq_complete(req)) + return; blk_delete_timer(req); blk_rq_timed_out(req); } @@ -123,33 +174,66 @@ void blk_add_timer(struct request *req) BUG_ON(!list_empty(&req->timeout_list)); BUG_ON(test_bit(REQ_ATOM_COMPLETE, &req->atomic_flags)); - if (req->timeout) - req->deadline = jiffies + req->timeout; - else { - req->deadline = jiffies + q->rq_timeout; - /* - * Some LLDs, like scsi, peek at the timeout to prevent - * a command from being retried forever. - */ + /* + * Some LLDs, like scsi, peek at the timeout to prevent a + * command from being retried forever. + */ + if (!req->timeout) req->timeout = q->rq_timeout; - } + + req->deadline = jiffies + req->timeout; list_add_tail(&req->timeout_list, &q->timeout_list); /* * If the timer isn't already pending or this timeout is earlier - * than an existing one, modify the timer. Round to next nearest + * than an existing one, modify the timer. Round up to next nearest * second. */ - expiry = round_jiffies(req->deadline); - - /* - * We use ->deadline == 0 to detect whether a timer was added or - * not, so just increase to next jiffy for that specific case - */ - if (unlikely(!req->deadline)) - req->deadline = 1; + expiry = round_jiffies_up(req->deadline); if (!timer_pending(&q->timeout) || time_before(expiry, q->timeout.expires)) mod_timer(&q->timeout, expiry); } + +/** + * blk_abort_queue -- Abort all request on given queue + * @queue: pointer to queue + * + */ +void blk_abort_queue(struct request_queue *q) +{ + unsigned long flags; + struct request *rq, *tmp; + LIST_HEAD(list); + + /* + * Not a request based block device, nothing to abort + */ + if (!q->request_fn) + return; + + spin_lock_irqsave(q->queue_lock, flags); + + elv_abort_queue(q); + + /* + * Splice entries to local list, to avoid deadlocking if entries + * get readded to the timeout list by error handling + */ + list_splice_init(&q->timeout_list, &list); + + list_for_each_entry_safe(rq, tmp, &list, timeout_list) + blk_abort_request(rq); + + /* + * Occasionally, blk_abort_request() will return without + * deleting the element from the list. Make sure we add those back + * instead of leaving them on the local stack list. + */ + list_splice(&list, &q->timeout_list); + + spin_unlock_irqrestore(q->queue_lock, flags); + +} +EXPORT_SYMBOL_GPL(blk_abort_queue);