From 935fe0983e09f4f7331ebf5ea4ae2124f6e9f9e8 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Tue, 10 Oct 2017 17:02:41 -0400 Subject: md: rename some drivers/md/ files to have an "md-" prefix Motivated by the desire to illiminate the imprecise nature of DM-specific patches being unnecessarily sent to both the MD maintainer and mailing-list. Which is born out of the fact that DM files also reside in drivers/md/ Now all MD-specific files in drivers/md/ start with either "raid" or "md-" and the MAINTAINERS file has been updated accordingly. Shaohua: don't change module name Signed-off-by: Mike Snitzer Signed-off-by: Shaohua Li --- drivers/md/multipath.c | 509 ------------------------------------------------- 1 file changed, 509 deletions(-) delete mode 100644 drivers/md/multipath.c (limited to 'drivers/md/multipath.c') diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c deleted file mode 100644 index b68e0666b9b0..000000000000 --- a/drivers/md/multipath.c +++ /dev/null @@ -1,509 +0,0 @@ -/* - * multipath.c : Multiple Devices driver for Linux - * - * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat - * - * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman - * - * MULTIPATH management functions. - * - * derived from raid1.c. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) - * any later version. - * - * You should have received a copy of the GNU General Public License - * (for example /usr/src/linux/COPYING); if not, write to the Free - * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -#include -#include -#include -#include -#include -#include "md.h" -#include "multipath.h" - -#define MAX_WORK_PER_DISK 128 - -#define NR_RESERVED_BUFS 32 - -static int multipath_map (struct mpconf *conf) -{ - int i, disks = conf->raid_disks; - - /* - * Later we do read balancing on the read side - * now we use the first available disk. - */ - - rcu_read_lock(); - for (i = 0; i < disks; i++) { - struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev); - if (rdev && test_bit(In_sync, &rdev->flags) && - !test_bit(Faulty, &rdev->flags)) { - atomic_inc(&rdev->nr_pending); - rcu_read_unlock(); - return i; - } - } - rcu_read_unlock(); - - pr_crit_ratelimited("multipath_map(): no more operational IO paths?\n"); - return (-1); -} - -static void multipath_reschedule_retry (struct multipath_bh *mp_bh) -{ - unsigned long flags; - struct mddev *mddev = mp_bh->mddev; - struct mpconf *conf = mddev->private; - - spin_lock_irqsave(&conf->device_lock, flags); - list_add(&mp_bh->retry_list, &conf->retry_list); - spin_unlock_irqrestore(&conf->device_lock, flags); - md_wakeup_thread(mddev->thread); -} - -/* - * multipath_end_bh_io() is called when we have finished servicing a multipathed - * operation and are ready to return a success/failure code to the buffer - * cache layer. - */ -static void multipath_end_bh_io(struct multipath_bh *mp_bh, blk_status_t status) -{ - struct bio *bio = mp_bh->master_bio; - struct mpconf *conf = mp_bh->mddev->private; - - bio->bi_status = status; - bio_endio(bio); - mempool_free(mp_bh, conf->pool); -} - -static void multipath_end_request(struct bio *bio) -{ - struct multipath_bh *mp_bh = bio->bi_private; - struct mpconf *conf = mp_bh->mddev->private; - struct md_rdev *rdev = conf->multipaths[mp_bh->path].rdev; - - if (!bio->bi_status) - multipath_end_bh_io(mp_bh, 0); - else if (!(bio->bi_opf & REQ_RAHEAD)) { - /* - * oops, IO error: - */ - char b[BDEVNAME_SIZE]; - md_error (mp_bh->mddev, rdev); - pr_info("multipath: %s: rescheduling sector %llu\n", - bdevname(rdev->bdev,b), - (unsigned long long)bio->bi_iter.bi_sector); - multipath_reschedule_retry(mp_bh); - } else - multipath_end_bh_io(mp_bh, bio->bi_status); - rdev_dec_pending(rdev, conf->mddev); -} - -static bool multipath_make_request(struct mddev *mddev, struct bio * bio) -{ - struct mpconf *conf = mddev->private; - struct multipath_bh * mp_bh; - struct multipath_info *multipath; - - if (unlikely(bio->bi_opf & REQ_PREFLUSH)) { - md_flush_request(mddev, bio); - return true; - } - - mp_bh = mempool_alloc(conf->pool, GFP_NOIO); - - mp_bh->master_bio = bio; - mp_bh->mddev = mddev; - - mp_bh->path = multipath_map(conf); - if (mp_bh->path < 0) { - bio_io_error(bio); - mempool_free(mp_bh, conf->pool); - return true; - } - multipath = conf->multipaths + mp_bh->path; - - bio_init(&mp_bh->bio, NULL, 0); - __bio_clone_fast(&mp_bh->bio, bio); - - mp_bh->bio.bi_iter.bi_sector += multipath->rdev->data_offset; - bio_set_dev(&mp_bh->bio, multipath->rdev->bdev); - mp_bh->bio.bi_opf |= REQ_FAILFAST_TRANSPORT; - mp_bh->bio.bi_end_io = multipath_end_request; - mp_bh->bio.bi_private = mp_bh; - mddev_check_writesame(mddev, &mp_bh->bio); - mddev_check_write_zeroes(mddev, &mp_bh->bio); - generic_make_request(&mp_bh->bio); - return true; -} - -static void multipath_status(struct seq_file *seq, struct mddev *mddev) -{ - struct mpconf *conf = mddev->private; - int i; - - seq_printf (seq, " [%d/%d] [", conf->raid_disks, - conf->raid_disks - mddev->degraded); - rcu_read_lock(); - for (i = 0; i < conf->raid_disks; i++) { - struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev); - seq_printf (seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); - } - rcu_read_unlock(); - seq_printf (seq, "]"); -} - -static int multipath_congested(struct mddev *mddev, int bits) -{ - struct mpconf *conf = mddev->private; - int i, ret = 0; - - rcu_read_lock(); - for (i = 0; i < mddev->raid_disks ; i++) { - struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev); - if (rdev && !test_bit(Faulty, &rdev->flags)) { - struct request_queue *q = bdev_get_queue(rdev->bdev); - - ret |= bdi_congested(q->backing_dev_info, bits); - /* Just like multipath_map, we just check the - * first available device - */ - break; - } - } - rcu_read_unlock(); - return ret; -} - -/* - * Careful, this can execute in IRQ contexts as well! - */ -static void multipath_error (struct mddev *mddev, struct md_rdev *rdev) -{ - struct mpconf *conf = mddev->private; - char b[BDEVNAME_SIZE]; - - if (conf->raid_disks - mddev->degraded <= 1) { - /* - * Uh oh, we can do nothing if this is our last path, but - * first check if this is a queued request for a device - * which has just failed. - */ - pr_warn("multipath: only one IO path left and IO error.\n"); - /* leave it active... it's all we have */ - return; - } - /* - * Mark disk as unusable - */ - if (test_and_clear_bit(In_sync, &rdev->flags)) { - unsigned long flags; - spin_lock_irqsave(&conf->device_lock, flags); - mddev->degraded++; - spin_unlock_irqrestore(&conf->device_lock, flags); - } - set_bit(Faulty, &rdev->flags); - set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags); - pr_err("multipath: IO failure on %s, disabling IO path.\n" - "multipath: Operation continuing on %d IO paths.\n", - bdevname(rdev->bdev, b), - conf->raid_disks - mddev->degraded); -} - -static void print_multipath_conf (struct mpconf *conf) -{ - int i; - struct multipath_info *tmp; - - pr_debug("MULTIPATH conf printout:\n"); - if (!conf) { - pr_debug("(conf==NULL)\n"); - return; - } - pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, - conf->raid_disks); - - for (i = 0; i < conf->raid_disks; i++) { - char b[BDEVNAME_SIZE]; - tmp = conf->multipaths + i; - if (tmp->rdev) - pr_debug(" disk%d, o:%d, dev:%s\n", - i,!test_bit(Faulty, &tmp->rdev->flags), - bdevname(tmp->rdev->bdev,b)); - } -} - -static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev) -{ - struct mpconf *conf = mddev->private; - struct request_queue *q; - int err = -EEXIST; - int path; - struct multipath_info *p; - int first = 0; - int last = mddev->raid_disks - 1; - - if (rdev->raid_disk >= 0) - first = last = rdev->raid_disk; - - print_multipath_conf(conf); - - for (path = first; path <= last; path++) - if ((p=conf->multipaths+path)->rdev == NULL) { - q = rdev->bdev->bd_disk->queue; - disk_stack_limits(mddev->gendisk, rdev->bdev, - rdev->data_offset << 9); - - err = md_integrity_add_rdev(rdev, mddev); - if (err) - break; - spin_lock_irq(&conf->device_lock); - mddev->degraded--; - rdev->raid_disk = path; - set_bit(In_sync, &rdev->flags); - spin_unlock_irq(&conf->device_lock); - rcu_assign_pointer(p->rdev, rdev); - err = 0; - break; - } - - print_multipath_conf(conf); - - return err; -} - -static int multipath_remove_disk(struct mddev *mddev, struct md_rdev *rdev) -{ - struct mpconf *conf = mddev->private; - int err = 0; - int number = rdev->raid_disk; - struct multipath_info *p = conf->multipaths + number; - - print_multipath_conf(conf); - - if (rdev == p->rdev) { - if (test_bit(In_sync, &rdev->flags) || - atomic_read(&rdev->nr_pending)) { - pr_warn("hot-remove-disk, slot %d is identified but is still operational!\n", number); - err = -EBUSY; - goto abort; - } - p->rdev = NULL; - if (!test_bit(RemoveSynchronized, &rdev->flags)) { - synchronize_rcu(); - if (atomic_read(&rdev->nr_pending)) { - /* lost the race, try later */ - err = -EBUSY; - p->rdev = rdev; - goto abort; - } - } - err = md_integrity_register(mddev); - } -abort: - - print_multipath_conf(conf); - return err; -} - -/* - * This is a kernel thread which: - * - * 1. Retries failed read operations on working multipaths. - * 2. Updates the raid superblock when problems encounter. - * 3. Performs writes following reads for array syncronising. - */ - -static void multipathd(struct md_thread *thread) -{ - struct mddev *mddev = thread->mddev; - struct multipath_bh *mp_bh; - struct bio *bio; - unsigned long flags; - struct mpconf *conf = mddev->private; - struct list_head *head = &conf->retry_list; - - md_check_recovery(mddev); - for (;;) { - char b[BDEVNAME_SIZE]; - spin_lock_irqsave(&conf->device_lock, flags); - if (list_empty(head)) - break; - mp_bh = list_entry(head->prev, struct multipath_bh, retry_list); - list_del(head->prev); - spin_unlock_irqrestore(&conf->device_lock, flags); - - bio = &mp_bh->bio; - bio->bi_iter.bi_sector = mp_bh->master_bio->bi_iter.bi_sector; - - if ((mp_bh->path = multipath_map (conf))<0) { - pr_err("multipath: %s: unrecoverable IO read error for block %llu\n", - bio_devname(bio, b), - (unsigned long long)bio->bi_iter.bi_sector); - multipath_end_bh_io(mp_bh, BLK_STS_IOERR); - } else { - pr_err("multipath: %s: redirecting sector %llu to another IO path\n", - bio_devname(bio, b), - (unsigned long long)bio->bi_iter.bi_sector); - *bio = *(mp_bh->master_bio); - bio->bi_iter.bi_sector += - conf->multipaths[mp_bh->path].rdev->data_offset; - bio_set_dev(bio, conf->multipaths[mp_bh->path].rdev->bdev); - bio->bi_opf |= REQ_FAILFAST_TRANSPORT; - bio->bi_end_io = multipath_end_request; - bio->bi_private = mp_bh; - generic_make_request(bio); - } - } - spin_unlock_irqrestore(&conf->device_lock, flags); -} - -static sector_t multipath_size(struct mddev *mddev, sector_t sectors, int raid_disks) -{ - WARN_ONCE(sectors || raid_disks, - "%s does not support generic reshape\n", __func__); - - return mddev->dev_sectors; -} - -static int multipath_run (struct mddev *mddev) -{ - struct mpconf *conf; - int disk_idx; - struct multipath_info *disk; - struct md_rdev *rdev; - int working_disks; - - if (md_check_no_bitmap(mddev)) - return -EINVAL; - - if (mddev->level != LEVEL_MULTIPATH) { - pr_warn("multipath: %s: raid level not set to multipath IO (%d)\n", - mdname(mddev), mddev->level); - goto out; - } - /* - * copy the already verified devices into our private MULTIPATH - * bookkeeping area. [whatever we allocate in multipath_run(), - * should be freed in multipath_free()] - */ - - conf = kzalloc(sizeof(struct mpconf), GFP_KERNEL); - mddev->private = conf; - if (!conf) - goto out; - - conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, - GFP_KERNEL); - if (!conf->multipaths) - goto out_free_conf; - - working_disks = 0; - rdev_for_each(rdev, mddev) { - disk_idx = rdev->raid_disk; - if (disk_idx < 0 || - disk_idx >= mddev->raid_disks) - continue; - - disk = conf->multipaths + disk_idx; - disk->rdev = rdev; - disk_stack_limits(mddev->gendisk, rdev->bdev, - rdev->data_offset << 9); - - if (!test_bit(Faulty, &rdev->flags)) - working_disks++; - } - - conf->raid_disks = mddev->raid_disks; - conf->mddev = mddev; - spin_lock_init(&conf->device_lock); - INIT_LIST_HEAD(&conf->retry_list); - - if (!working_disks) { - pr_warn("multipath: no operational IO paths for %s\n", - mdname(mddev)); - goto out_free_conf; - } - mddev->degraded = conf->raid_disks - working_disks; - - conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS, - sizeof(struct multipath_bh)); - if (conf->pool == NULL) - goto out_free_conf; - - mddev->thread = md_register_thread(multipathd, mddev, - "multipath"); - if (!mddev->thread) - goto out_free_conf; - - pr_info("multipath: array %s active with %d out of %d IO paths\n", - mdname(mddev), conf->raid_disks - mddev->degraded, - mddev->raid_disks); - /* - * Ok, everything is just fine now - */ - md_set_array_sectors(mddev, multipath_size(mddev, 0, 0)); - - if (md_integrity_register(mddev)) - goto out_free_conf; - - return 0; - -out_free_conf: - mempool_destroy(conf->pool); - kfree(conf->multipaths); - kfree(conf); - mddev->private = NULL; -out: - return -EIO; -} - -static void multipath_free(struct mddev *mddev, void *priv) -{ - struct mpconf *conf = priv; - - mempool_destroy(conf->pool); - kfree(conf->multipaths); - kfree(conf); -} - -static struct md_personality multipath_personality = -{ - .name = "multipath", - .level = LEVEL_MULTIPATH, - .owner = THIS_MODULE, - .make_request = multipath_make_request, - .run = multipath_run, - .free = multipath_free, - .status = multipath_status, - .error_handler = multipath_error, - .hot_add_disk = multipath_add_disk, - .hot_remove_disk= multipath_remove_disk, - .size = multipath_size, - .congested = multipath_congested, -}; - -static int __init multipath_init (void) -{ - return register_md_personality (&multipath_personality); -} - -static void __exit multipath_exit (void) -{ - unregister_md_personality (&multipath_personality); -} - -module_init(multipath_init); -module_exit(multipath_exit); -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("simple multi-path personality for MD"); -MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ -MODULE_ALIAS("md-multipath"); -MODULE_ALIAS("md-level--4"); -- cgit v1.2.3