Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2)  * Copyright (C) 2005-2007 Red Hat GmbH
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * A target that delays reads and/or writes and can send
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * them to different devices.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  * This file is released under the GPL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/blkdev.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/bio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/device-mapper.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #define DM_MSG_PREFIX "delay"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) struct delay_class {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 	struct dm_dev *dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	sector_t start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	unsigned delay;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	unsigned ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) struct delay_c {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	struct timer_list delay_timer;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	struct mutex timer_lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	struct workqueue_struct *kdelayd_wq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	struct work_struct flush_expired_bios;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	struct list_head delayed_bios;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	atomic_t may_delay;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	struct delay_class read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	struct delay_class write;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	struct delay_class flush;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	int argc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) struct dm_delay_info {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	struct delay_c *context;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	struct delay_class *class;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	struct list_head list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	unsigned long expires;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) static DEFINE_MUTEX(delayed_bios_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) static void handle_delayed_timer(struct timer_list *t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	struct delay_c *dc = from_timer(dc, t, delay_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	queue_work(dc->kdelayd_wq, &dc->flush_expired_bios);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) static void queue_timeout(struct delay_c *dc, unsigned long expires)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	mutex_lock(&dc->timer_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	if (!timer_pending(&dc->delay_timer) || expires < dc->delay_timer.expires)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 		mod_timer(&dc->delay_timer, expires);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	mutex_unlock(&dc->timer_lock);
^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) static void flush_bios(struct bio *bio)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	struct bio *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	while (bio) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		n = bio->bi_next;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 		bio->bi_next = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		submit_bio_noacct(bio);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 		bio = n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) static struct bio *flush_delayed_bios(struct delay_c *dc, int flush_all)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	struct dm_delay_info *delayed, *next;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	unsigned long next_expires = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	unsigned long start_timer = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	struct bio_list flush_bios = { };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	mutex_lock(&delayed_bios_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	list_for_each_entry_safe(delayed, next, &dc->delayed_bios, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 		if (flush_all || time_after_eq(jiffies, delayed->expires)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 			struct bio *bio = dm_bio_from_per_bio_data(delayed,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 						sizeof(struct dm_delay_info));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 			list_del(&delayed->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 			bio_list_add(&flush_bios, bio);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 			delayed->class->ops--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		if (!start_timer) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 			start_timer = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 			next_expires = delayed->expires;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		} else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 			next_expires = min(next_expires, delayed->expires);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	mutex_unlock(&delayed_bios_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	if (start_timer)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 		queue_timeout(dc, next_expires);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	return bio_list_get(&flush_bios);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) static void flush_expired_bios(struct work_struct *work)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	struct delay_c *dc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	dc = container_of(work, struct delay_c, flush_expired_bios);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	flush_bios(flush_delayed_bios(dc, 0));
^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) static void delay_dtr(struct dm_target *ti)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	struct delay_c *dc = ti->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	if (dc->kdelayd_wq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 		destroy_workqueue(dc->kdelayd_wq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	if (dc->read.dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 		dm_put_device(ti, dc->read.dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	if (dc->write.dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 		dm_put_device(ti, dc->write.dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	if (dc->flush.dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 		dm_put_device(ti, dc->flush.dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	mutex_destroy(&dc->timer_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	kfree(dc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) static int delay_class_ctr(struct dm_target *ti, struct delay_class *c, char **argv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	unsigned long long tmpll;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	char dummy;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	if (sscanf(argv[1], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 		ti->error = "Invalid device sector";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	c->start = tmpll;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	if (sscanf(argv[2], "%u%c", &c->delay, &dummy) != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 		ti->error = "Invalid delay";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	ret = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &c->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 		ti->error = "Device lookup failed";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 		return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166)  * Mapping parameters:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)  *    <device> <offset> <delay> [<write_device> <write_offset> <write_delay>]
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)  * With separate write parameters, the first set is only used for reads.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)  * Offsets are specified in sectors.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)  * Delays are specified in milliseconds.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) static int delay_ctr(struct dm_target *ti, unsigned int argc, char **argv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	struct delay_c *dc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	if (argc != 3 && argc != 6 && argc != 9) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		ti->error = "Requires exactly 3, 6 or 9 arguments";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	dc = kzalloc(sizeof(*dc), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	if (!dc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 		ti->error = "Cannot allocate context";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	ti->private = dc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	timer_setup(&dc->delay_timer, handle_delayed_timer, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	INIT_WORK(&dc->flush_expired_bios, flush_expired_bios);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	INIT_LIST_HEAD(&dc->delayed_bios);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	mutex_init(&dc->timer_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	atomic_set(&dc->may_delay, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 	dc->argc = argc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	ret = delay_class_ctr(ti, &dc->read, argv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 		goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 	if (argc == 3) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 		ret = delay_class_ctr(ti, &dc->write, argv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 			goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 		ret = delay_class_ctr(ti, &dc->flush, argv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 			goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 	ret = delay_class_ctr(ti, &dc->write, argv + 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 		goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 	if (argc == 6) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 		ret = delay_class_ctr(ti, &dc->flush, argv + 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 			goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 	ret = delay_class_ctr(ti, &dc->flush, argv + 6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 		goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 	dc->kdelayd_wq = alloc_workqueue("kdelayd", WQ_MEM_RECLAIM, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 	if (!dc->kdelayd_wq) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 		ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 		DMERR("Couldn't start kdelayd");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 		goto bad;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 	ti->num_flush_bios = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 	ti->num_discard_bios = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 	ti->per_io_data_size = sizeof(struct dm_delay_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) bad:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 	delay_dtr(ti);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) static int delay_bio(struct delay_c *dc, struct delay_class *c, struct bio *bio)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	struct dm_delay_info *delayed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 	unsigned long expires = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	if (!c->delay || !atomic_read(&dc->may_delay))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 		return DM_MAPIO_REMAPPED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 	delayed = dm_per_bio_data(bio, sizeof(struct dm_delay_info));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 	delayed->context = dc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 	delayed->expires = expires = jiffies + msecs_to_jiffies(c->delay);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 	mutex_lock(&delayed_bios_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 	c->ops++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 	list_add_tail(&delayed->list, &dc->delayed_bios);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) 	mutex_unlock(&delayed_bios_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	queue_timeout(dc, expires);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 	return DM_MAPIO_SUBMITTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) static void delay_presuspend(struct dm_target *ti)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 	struct delay_c *dc = ti->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 	atomic_set(&dc->may_delay, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	del_timer_sync(&dc->delay_timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 	flush_bios(flush_delayed_bios(dc, 1));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) static void delay_resume(struct dm_target *ti)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 	struct delay_c *dc = ti->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 	atomic_set(&dc->may_delay, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) static int delay_map(struct dm_target *ti, struct bio *bio)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 	struct delay_c *dc = ti->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 	struct delay_class *c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 	struct dm_delay_info *delayed = dm_per_bio_data(bio, sizeof(struct dm_delay_info));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 	if (bio_data_dir(bio) == WRITE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 		if (unlikely(bio->bi_opf & REQ_PREFLUSH))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 			c = &dc->flush;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 		else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 			c = &dc->write;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 		c = &dc->read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) 	delayed->class = c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) 	bio_set_dev(bio, c->dev->bdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 	if (bio_sectors(bio))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) 		bio->bi_iter.bi_sector = c->start + dm_target_offset(ti, bio->bi_iter.bi_sector);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) 	return delay_bio(dc, c, bio);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) #define DMEMIT_DELAY_CLASS(c) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 	DMEMIT("%s %llu %u", (c)->dev->name, (unsigned long long)(c)->start, (c)->delay)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) static void delay_status(struct dm_target *ti, status_type_t type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 			 unsigned status_flags, char *result, unsigned maxlen)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 	struct delay_c *dc = ti->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	int sz = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 	switch (type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 	case STATUSTYPE_INFO:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 		DMEMIT("%u %u %u", dc->read.ops, dc->write.ops, dc->flush.ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 	case STATUSTYPE_TABLE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) 		DMEMIT_DELAY_CLASS(&dc->read);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) 		if (dc->argc >= 6) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 			DMEMIT(" ");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 			DMEMIT_DELAY_CLASS(&dc->write);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 		if (dc->argc >= 9) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 			DMEMIT(" ");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 			DMEMIT_DELAY_CLASS(&dc->flush);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) static int delay_iterate_devices(struct dm_target *ti,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 				 iterate_devices_callout_fn fn, void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 	struct delay_c *dc = ti->private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 	int ret = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) 	ret = fn(ti, dc->read.dev, dc->read.start, ti->len, data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) 	ret = fn(ti, dc->write.dev, dc->write.start, ti->len, data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) 	ret = fn(ti, dc->flush.dev, dc->flush.start, ti->len, data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) static struct target_type delay_target = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) 	.name	     = "delay",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) 	.version     = {1, 2, 1},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) 	.features    = DM_TARGET_PASSES_INTEGRITY,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) 	.module      = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) 	.ctr	     = delay_ctr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) 	.dtr	     = delay_dtr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) 	.map	     = delay_map,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) 	.presuspend  = delay_presuspend,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) 	.resume	     = delay_resume,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) 	.status	     = delay_status,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) 	.iterate_devices = delay_iterate_devices,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) static int __init dm_delay_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) 	int r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) 	r = dm_register_target(&delay_target);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) 	if (r < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) 		DMERR("register failed %d", r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) 		goto bad_register;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) bad_register:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) 	return r;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) static void __exit dm_delay_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) 	dm_unregister_target(&delay_target);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) /* Module hooks */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) module_init(dm_delay_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) module_exit(dm_delay_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) MODULE_DESCRIPTION(DM_NAME " delay target");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) MODULE_AUTHOR("Heinz Mauelshagen <mauelshagen@redhat.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) MODULE_LICENSE("GPL");