linux/block/blk-timeout.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Functions related to generic timeout handling of requests.
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/fault-inject.h>

#include "blk.h"
#include "blk-mq.h"

#ifdef CONFIG_FAIL_IO_TIMEOUT

static DECLARE_FAULT_ATTR(fail_io_timeout);

static int __init setup_fail_io_timeout(char *str)
{ … }
__setup(…);

bool __blk_should_fake_timeout(struct request_queue *q)
{ … }
EXPORT_SYMBOL_GPL(…);

static int __init fail_io_timeout_debugfs(void)
{ … }

late_initcall(fail_io_timeout_debugfs);

ssize_t part_timeout_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{ … }

ssize_t part_timeout_store(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t count)
{ … }

#endif /* CONFIG_FAIL_IO_TIMEOUT */

/**
 * blk_abort_request - Request recovery for the specified command
 * @req:	pointer to the request of interest
 *
 * This function requests that the block layer start recovery for the
 * request by deleting the timer and calling the q's timeout function.
 * LLDDs who implement their own error recovery MAY ignore the timeout
 * event if they generated blk_abort_request.
 */
void blk_abort_request(struct request *req)
{ … }
EXPORT_SYMBOL_GPL(…);

static unsigned long blk_timeout_mask __read_mostly;

static int __init blk_timeout_init(void)
{ … }

late_initcall(blk_timeout_init);

/*
 * Just a rough estimate, we don't care about specific values for timeouts.
 */
static inline unsigned long blk_round_jiffies(unsigned long j)
{ … }

unsigned long blk_rq_timeout(unsigned long timeout)
{ … }

/**
 * blk_add_timer - Start timeout timer for a single request
 * @req:	request that is about to start running.
 *
 * Notes:
 *    Each request has its own timer, and as it is added to the queue, we
 *    set up the timer. When the request completes, we cancel the timer.
 */
void blk_add_timer(struct request *req)
{ … }