^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Functions related to generic timeout handling of requests.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/blkdev.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/fault-inject.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include "blk.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include "blk-mq.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #ifdef CONFIG_FAIL_IO_TIMEOUT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) static DECLARE_FAULT_ATTR(fail_io_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) static int __init setup_fail_io_timeout(char *str)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) return setup_fault_attr(&fail_io_timeout, str);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) __setup("fail_io_timeout=", setup_fail_io_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) bool __blk_should_fake_timeout(struct request_queue *q)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) return should_fail(&fail_io_timeout, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) EXPORT_SYMBOL_GPL(__blk_should_fake_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) static int __init fail_io_timeout_debugfs(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) struct dentry *dir = fault_create_debugfs_attr("fail_io_timeout",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) NULL, &fail_io_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) return PTR_ERR_OR_ZERO(dir);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) late_initcall(fail_io_timeout_debugfs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) ssize_t part_timeout_show(struct device *dev, struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) struct gendisk *disk = dev_to_disk(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) int set = test_bit(QUEUE_FLAG_FAIL_IO, &disk->queue->queue_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) return sprintf(buf, "%d\n", set != 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) ssize_t part_timeout_store(struct device *dev, struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) const char *buf, size_t count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) struct gendisk *disk = dev_to_disk(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) int val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) if (count) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct request_queue *q = disk->queue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) char *p = (char *) buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) val = simple_strtoul(p, &p, 10);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) if (val)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) blk_queue_flag_set(QUEUE_FLAG_FAIL_IO, q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) blk_queue_flag_clear(QUEUE_FLAG_FAIL_IO, q);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) #endif /* CONFIG_FAIL_IO_TIMEOUT */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) * blk_abort_request - Request recovery for the specified command
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) * @req: pointer to the request of interest
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) * This function requests that the block layer start recovery for the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) * request by deleting the timer and calling the q's timeout function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) * LLDDs who implement their own error recovery MAY ignore the timeout
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) * event if they generated blk_abort_request.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) void blk_abort_request(struct request *req)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) * All we need to ensure is that timeout scan takes place
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) * immediately and that scan sees the new timeout value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) * No need for fancy synchronizations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) WRITE_ONCE(req->deadline, jiffies);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) kblockd_schedule_work(&req->q->timeout_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) EXPORT_SYMBOL_GPL(blk_abort_request);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) static unsigned long blk_timeout_mask __read_mostly;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) static int __init blk_timeout_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) blk_timeout_mask = roundup_pow_of_two(HZ) - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) late_initcall(blk_timeout_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) * Just a rough estimate, we don't care about specific values for timeouts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static inline unsigned long blk_round_jiffies(unsigned long j)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) return (j + blk_timeout_mask) + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) unsigned long blk_rq_timeout(unsigned long timeout)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) unsigned long maxt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) maxt = blk_round_jiffies(jiffies + BLK_MAX_TIMEOUT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) if (time_after(timeout, maxt))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) timeout = maxt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) return timeout;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * blk_add_timer - Start timeout timer for a single request
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * @req: request that is about to start running.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) * Notes:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) * Each request has its own timer, and as it is added to the queue, we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) * set up the timer. When the request completes, we cancel the timer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) void blk_add_timer(struct request *req)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) struct request_queue *q = req->q;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) unsigned long expiry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) * Some LLDs, like scsi, peek at the timeout to prevent a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) * command from being retried forever.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) if (!req->timeout)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) req->timeout = q->rq_timeout;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) req->rq_flags &= ~RQF_TIMED_OUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) expiry = jiffies + req->timeout;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) WRITE_ONCE(req->deadline, expiry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) * If the timer isn't already pending or this timeout is earlier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) * than an existing one, modify the timer. Round up to next nearest
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) * second.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) expiry = blk_rq_timeout(blk_round_jiffies(expiry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) if (!timer_pending(&q->timeout) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) time_before(expiry, q->timeout.expires)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) unsigned long diff = q->timeout.expires - expiry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) * Due to added timer slack to group timers, the timer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) * will often be a little in front of what we asked for.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) * So apply some tolerance here too, otherwise we keep
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) * modifying the timer because expires for value X
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) * will be X + something.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) if (!timer_pending(&q->timeout) || (diff >= HZ / 2))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) mod_timer(&q->timeout, expiry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags