![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
1450 lines
35 KiB
C
1450 lines
35 KiB
C
/*
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* raid1.c : Multiple Devices driver for Linux
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*
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* Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
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*
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* Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
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*
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* RAID-1 management functions.
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*
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* Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
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*
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* Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
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* Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2, or (at your option)
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* any later version.
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*
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* You should have received a copy of the GNU General Public License
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* (for example /usr/src/linux/COPYING); if not, write to the Free
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* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <linux/raid/raid1.h>
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/*
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* Number of guaranteed r1bios in case of extreme VM load:
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*/
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#define NR_RAID1_BIOS 256
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static mdk_personality_t raid1_personality;
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static void unplug_slaves(mddev_t *mddev);
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static void * r1bio_pool_alloc(unsigned int __nocast gfp_flags, void *data)
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{
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struct pool_info *pi = data;
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r1bio_t *r1_bio;
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int size = offsetof(r1bio_t, bios[pi->raid_disks]);
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/* allocate a r1bio with room for raid_disks entries in the bios array */
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r1_bio = kmalloc(size, gfp_flags);
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if (r1_bio)
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memset(r1_bio, 0, size);
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else
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unplug_slaves(pi->mddev);
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return r1_bio;
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}
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static void r1bio_pool_free(void *r1_bio, void *data)
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{
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kfree(r1_bio);
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}
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#define RESYNC_BLOCK_SIZE (64*1024)
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//#define RESYNC_BLOCK_SIZE PAGE_SIZE
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#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
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#define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
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#define RESYNC_WINDOW (2048*1024)
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static void * r1buf_pool_alloc(unsigned int __nocast gfp_flags, void *data)
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{
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struct pool_info *pi = data;
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struct page *page;
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r1bio_t *r1_bio;
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struct bio *bio;
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int i, j;
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r1_bio = r1bio_pool_alloc(gfp_flags, pi);
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if (!r1_bio) {
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unplug_slaves(pi->mddev);
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return NULL;
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}
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/*
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* Allocate bios : 1 for reading, n-1 for writing
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*/
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for (j = pi->raid_disks ; j-- ; ) {
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bio = bio_alloc(gfp_flags, RESYNC_PAGES);
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if (!bio)
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goto out_free_bio;
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r1_bio->bios[j] = bio;
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}
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/*
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* Allocate RESYNC_PAGES data pages and attach them to
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* the first bio;
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*/
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bio = r1_bio->bios[0];
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for (i = 0; i < RESYNC_PAGES; i++) {
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page = alloc_page(gfp_flags);
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if (unlikely(!page))
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goto out_free_pages;
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bio->bi_io_vec[i].bv_page = page;
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}
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r1_bio->master_bio = NULL;
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return r1_bio;
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out_free_pages:
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for ( ; i > 0 ; i--)
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__free_page(bio->bi_io_vec[i-1].bv_page);
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out_free_bio:
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while ( ++j < pi->raid_disks )
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bio_put(r1_bio->bios[j]);
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r1bio_pool_free(r1_bio, data);
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return NULL;
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}
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static void r1buf_pool_free(void *__r1_bio, void *data)
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{
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struct pool_info *pi = data;
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int i;
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r1bio_t *r1bio = __r1_bio;
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struct bio *bio = r1bio->bios[0];
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for (i = 0; i < RESYNC_PAGES; i++) {
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__free_page(bio->bi_io_vec[i].bv_page);
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bio->bi_io_vec[i].bv_page = NULL;
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}
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for (i=0 ; i < pi->raid_disks; i++)
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bio_put(r1bio->bios[i]);
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r1bio_pool_free(r1bio, data);
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}
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static void put_all_bios(conf_t *conf, r1bio_t *r1_bio)
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{
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int i;
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for (i = 0; i < conf->raid_disks; i++) {
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struct bio **bio = r1_bio->bios + i;
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if (*bio)
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bio_put(*bio);
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*bio = NULL;
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}
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}
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static inline void free_r1bio(r1bio_t *r1_bio)
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{
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unsigned long flags;
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conf_t *conf = mddev_to_conf(r1_bio->mddev);
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/*
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* Wake up any possible resync thread that waits for the device
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* to go idle.
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*/
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spin_lock_irqsave(&conf->resync_lock, flags);
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if (!--conf->nr_pending) {
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wake_up(&conf->wait_idle);
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wake_up(&conf->wait_resume);
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}
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spin_unlock_irqrestore(&conf->resync_lock, flags);
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put_all_bios(conf, r1_bio);
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mempool_free(r1_bio, conf->r1bio_pool);
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}
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static inline void put_buf(r1bio_t *r1_bio)
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{
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conf_t *conf = mddev_to_conf(r1_bio->mddev);
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unsigned long flags;
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mempool_free(r1_bio, conf->r1buf_pool);
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spin_lock_irqsave(&conf->resync_lock, flags);
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if (!conf->barrier)
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BUG();
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--conf->barrier;
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wake_up(&conf->wait_resume);
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wake_up(&conf->wait_idle);
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if (!--conf->nr_pending) {
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wake_up(&conf->wait_idle);
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wake_up(&conf->wait_resume);
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}
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spin_unlock_irqrestore(&conf->resync_lock, flags);
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}
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static void reschedule_retry(r1bio_t *r1_bio)
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{
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unsigned long flags;
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mddev_t *mddev = r1_bio->mddev;
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conf_t *conf = mddev_to_conf(mddev);
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spin_lock_irqsave(&conf->device_lock, flags);
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list_add(&r1_bio->retry_list, &conf->retry_list);
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spin_unlock_irqrestore(&conf->device_lock, flags);
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md_wakeup_thread(mddev->thread);
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}
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/*
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* raid_end_bio_io() is called when we have finished servicing a mirrored
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* operation and are ready to return a success/failure code to the buffer
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* cache layer.
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*/
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static void raid_end_bio_io(r1bio_t *r1_bio)
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{
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struct bio *bio = r1_bio->master_bio;
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bio_endio(bio, bio->bi_size,
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test_bit(R1BIO_Uptodate, &r1_bio->state) ? 0 : -EIO);
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free_r1bio(r1_bio);
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}
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/*
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* Update disk head position estimator based on IRQ completion info.
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*/
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static inline void update_head_pos(int disk, r1bio_t *r1_bio)
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{
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conf_t *conf = mddev_to_conf(r1_bio->mddev);
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conf->mirrors[disk].head_position =
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r1_bio->sector + (r1_bio->sectors);
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}
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static int raid1_end_read_request(struct bio *bio, unsigned int bytes_done, int error)
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{
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int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
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r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
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int mirror;
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conf_t *conf = mddev_to_conf(r1_bio->mddev);
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if (bio->bi_size)
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return 1;
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mirror = r1_bio->read_disk;
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/*
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* this branch is our 'one mirror IO has finished' event handler:
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*/
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if (!uptodate)
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md_error(r1_bio->mddev, conf->mirrors[mirror].rdev);
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else
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/*
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* Set R1BIO_Uptodate in our master bio, so that
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* we will return a good error code for to the higher
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* levels even if IO on some other mirrored buffer fails.
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*
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* The 'master' represents the composite IO operation to
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* user-side. So if something waits for IO, then it will
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* wait for the 'master' bio.
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*/
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set_bit(R1BIO_Uptodate, &r1_bio->state);
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update_head_pos(mirror, r1_bio);
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/*
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* we have only one bio on the read side
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*/
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if (uptodate)
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raid_end_bio_io(r1_bio);
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else {
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/*
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* oops, read error:
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*/
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char b[BDEVNAME_SIZE];
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if (printk_ratelimit())
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printk(KERN_ERR "raid1: %s: rescheduling sector %llu\n",
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bdevname(conf->mirrors[mirror].rdev->bdev,b), (unsigned long long)r1_bio->sector);
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reschedule_retry(r1_bio);
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}
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rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
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return 0;
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}
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static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int error)
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{
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int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
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r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
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int mirror;
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conf_t *conf = mddev_to_conf(r1_bio->mddev);
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if (bio->bi_size)
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return 1;
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for (mirror = 0; mirror < conf->raid_disks; mirror++)
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if (r1_bio->bios[mirror] == bio)
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break;
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/*
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* this branch is our 'one mirror IO has finished' event handler:
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*/
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if (!uptodate)
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md_error(r1_bio->mddev, conf->mirrors[mirror].rdev);
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else
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/*
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* Set R1BIO_Uptodate in our master bio, so that
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* we will return a good error code for to the higher
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* levels even if IO on some other mirrored buffer fails.
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*
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* The 'master' represents the composite IO operation to
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* user-side. So if something waits for IO, then it will
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* wait for the 'master' bio.
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*/
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set_bit(R1BIO_Uptodate, &r1_bio->state);
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update_head_pos(mirror, r1_bio);
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/*
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*
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* Let's see if all mirrored write operations have finished
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* already.
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*/
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if (atomic_dec_and_test(&r1_bio->remaining)) {
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md_write_end(r1_bio->mddev);
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raid_end_bio_io(r1_bio);
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}
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rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
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return 0;
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}
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/*
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* This routine returns the disk from which the requested read should
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* be done. There is a per-array 'next expected sequential IO' sector
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* number - if this matches on the next IO then we use the last disk.
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* There is also a per-disk 'last know head position' sector that is
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* maintained from IRQ contexts, both the normal and the resync IO
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* completion handlers update this position correctly. If there is no
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* perfect sequential match then we pick the disk whose head is closest.
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*
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* If there are 2 mirrors in the same 2 devices, performance degrades
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* because position is mirror, not device based.
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*
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* The rdev for the device selected will have nr_pending incremented.
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*/
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static int read_balance(conf_t *conf, r1bio_t *r1_bio)
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{
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const unsigned long this_sector = r1_bio->sector;
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int new_disk = conf->last_used, disk = new_disk;
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const int sectors = r1_bio->sectors;
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sector_t new_distance, current_distance;
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mdk_rdev_t *new_rdev, *rdev;
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rcu_read_lock();
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/*
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* Check if it if we can balance. We can balance on the whole
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* device if no resync is going on, or below the resync window.
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* We take the first readable disk when above the resync window.
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*/
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retry:
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if (conf->mddev->recovery_cp < MaxSector &&
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(this_sector + sectors >= conf->next_resync)) {
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/* Choose the first operation device, for consistancy */
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new_disk = 0;
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while ((new_rdev=conf->mirrors[new_disk].rdev) == NULL ||
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!new_rdev->in_sync) {
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new_disk++;
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if (new_disk == conf->raid_disks) {
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new_disk = -1;
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break;
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}
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}
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goto rb_out;
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}
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/* make sure the disk is operational */
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while ((new_rdev=conf->mirrors[new_disk].rdev) == NULL ||
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!new_rdev->in_sync) {
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if (new_disk <= 0)
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new_disk = conf->raid_disks;
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new_disk--;
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if (new_disk == disk) {
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new_disk = -1;
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goto rb_out;
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}
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}
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disk = new_disk;
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/* now disk == new_disk == starting point for search */
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/*
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* Don't change to another disk for sequential reads:
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*/
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if (conf->next_seq_sect == this_sector)
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goto rb_out;
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if (this_sector == conf->mirrors[new_disk].head_position)
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goto rb_out;
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current_distance = abs(this_sector - conf->mirrors[disk].head_position);
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/* Find the disk whose head is closest */
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do {
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if (disk <= 0)
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disk = conf->raid_disks;
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disk--;
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if ((rdev=conf->mirrors[disk].rdev) == NULL ||
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!rdev->in_sync)
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continue;
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if (!atomic_read(&rdev->nr_pending)) {
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new_disk = disk;
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new_rdev = rdev;
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break;
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}
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new_distance = abs(this_sector - conf->mirrors[disk].head_position);
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if (new_distance < current_distance) {
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current_distance = new_distance;
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new_disk = disk;
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new_rdev = rdev;
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}
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} while (disk != conf->last_used);
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rb_out:
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if (new_disk >= 0) {
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conf->next_seq_sect = this_sector + sectors;
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conf->last_used = new_disk;
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atomic_inc(&new_rdev->nr_pending);
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if (!new_rdev->in_sync) {
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/* cannot risk returning a device that failed
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* before we inc'ed nr_pending
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*/
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atomic_dec(&new_rdev->nr_pending);
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goto retry;
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}
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}
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rcu_read_unlock();
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return new_disk;
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}
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static void unplug_slaves(mddev_t *mddev)
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{
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conf_t *conf = mddev_to_conf(mddev);
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int i;
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rcu_read_lock();
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for (i=0; i<mddev->raid_disks; i++) {
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mdk_rdev_t *rdev = conf->mirrors[i].rdev;
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if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
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request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
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atomic_inc(&rdev->nr_pending);
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rcu_read_unlock();
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if (r_queue->unplug_fn)
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r_queue->unplug_fn(r_queue);
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rdev_dec_pending(rdev, mddev);
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rcu_read_lock();
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}
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}
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rcu_read_unlock();
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}
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|
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static void raid1_unplug(request_queue_t *q)
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{
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unplug_slaves(q->queuedata);
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}
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|
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static int raid1_issue_flush(request_queue_t *q, struct gendisk *disk,
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sector_t *error_sector)
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{
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mddev_t *mddev = q->queuedata;
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conf_t *conf = mddev_to_conf(mddev);
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int i, ret = 0;
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rcu_read_lock();
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for (i=0; i<mddev->raid_disks && ret == 0; i++) {
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mdk_rdev_t *rdev = conf->mirrors[i].rdev;
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if (rdev && !rdev->faulty) {
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struct block_device *bdev = rdev->bdev;
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request_queue_t *r_queue = bdev_get_queue(bdev);
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if (!r_queue->issue_flush_fn)
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ret = -EOPNOTSUPP;
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else {
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atomic_inc(&rdev->nr_pending);
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rcu_read_unlock();
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ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
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error_sector);
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rdev_dec_pending(rdev, mddev);
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rcu_read_lock();
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}
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}
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}
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rcu_read_unlock();
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return ret;
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}
|
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|
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/*
|
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* Throttle resync depth, so that we can both get proper overlapping of
|
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* requests, but are still able to handle normal requests quickly.
|
|
*/
|
|
#define RESYNC_DEPTH 32
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|
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static void device_barrier(conf_t *conf, sector_t sect)
|
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{
|
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spin_lock_irq(&conf->resync_lock);
|
|
wait_event_lock_irq(conf->wait_idle, !waitqueue_active(&conf->wait_resume),
|
|
conf->resync_lock, unplug_slaves(conf->mddev));
|
|
|
|
if (!conf->barrier++) {
|
|
wait_event_lock_irq(conf->wait_idle, !conf->nr_pending,
|
|
conf->resync_lock, unplug_slaves(conf->mddev));
|
|
if (conf->nr_pending)
|
|
BUG();
|
|
}
|
|
wait_event_lock_irq(conf->wait_resume, conf->barrier < RESYNC_DEPTH,
|
|
conf->resync_lock, unplug_slaves(conf->mddev));
|
|
conf->next_resync = sect;
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
}
|
|
|
|
static int make_request(request_queue_t *q, struct bio * bio)
|
|
{
|
|
mddev_t *mddev = q->queuedata;
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
mirror_info_t *mirror;
|
|
r1bio_t *r1_bio;
|
|
struct bio *read_bio;
|
|
int i, disks;
|
|
mdk_rdev_t *rdev;
|
|
|
|
/*
|
|
* Register the new request and wait if the reconstruction
|
|
* thread has put up a bar for new requests.
|
|
* Continue immediately if no resync is active currently.
|
|
*/
|
|
spin_lock_irq(&conf->resync_lock);
|
|
wait_event_lock_irq(conf->wait_resume, !conf->barrier, conf->resync_lock, );
|
|
conf->nr_pending++;
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
|
|
if (bio_data_dir(bio)==WRITE) {
|
|
disk_stat_inc(mddev->gendisk, writes);
|
|
disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
|
|
} else {
|
|
disk_stat_inc(mddev->gendisk, reads);
|
|
disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
|
|
}
|
|
|
|
/*
|
|
* make_request() can abort the operation when READA is being
|
|
* used and no empty request is available.
|
|
*
|
|
*/
|
|
r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
|
|
|
|
r1_bio->master_bio = bio;
|
|
r1_bio->sectors = bio->bi_size >> 9;
|
|
|
|
r1_bio->mddev = mddev;
|
|
r1_bio->sector = bio->bi_sector;
|
|
|
|
r1_bio->state = 0;
|
|
|
|
if (bio_data_dir(bio) == READ) {
|
|
/*
|
|
* read balancing logic:
|
|
*/
|
|
int rdisk = read_balance(conf, r1_bio);
|
|
|
|
if (rdisk < 0) {
|
|
/* couldn't find anywhere to read from */
|
|
raid_end_bio_io(r1_bio);
|
|
return 0;
|
|
}
|
|
mirror = conf->mirrors + rdisk;
|
|
|
|
r1_bio->read_disk = rdisk;
|
|
|
|
read_bio = bio_clone(bio, GFP_NOIO);
|
|
|
|
r1_bio->bios[rdisk] = read_bio;
|
|
|
|
read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset;
|
|
read_bio->bi_bdev = mirror->rdev->bdev;
|
|
read_bio->bi_end_io = raid1_end_read_request;
|
|
read_bio->bi_rw = READ;
|
|
read_bio->bi_private = r1_bio;
|
|
|
|
generic_make_request(read_bio);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* WRITE:
|
|
*/
|
|
/* first select target devices under spinlock and
|
|
* inc refcount on their rdev. Record them by setting
|
|
* bios[x] to bio
|
|
*/
|
|
disks = conf->raid_disks;
|
|
rcu_read_lock();
|
|
for (i = 0; i < disks; i++) {
|
|
if ((rdev=conf->mirrors[i].rdev) != NULL &&
|
|
!rdev->faulty) {
|
|
atomic_inc(&rdev->nr_pending);
|
|
if (rdev->faulty) {
|
|
atomic_dec(&rdev->nr_pending);
|
|
r1_bio->bios[i] = NULL;
|
|
} else
|
|
r1_bio->bios[i] = bio;
|
|
} else
|
|
r1_bio->bios[i] = NULL;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
atomic_set(&r1_bio->remaining, 1);
|
|
md_write_start(mddev);
|
|
for (i = 0; i < disks; i++) {
|
|
struct bio *mbio;
|
|
if (!r1_bio->bios[i])
|
|
continue;
|
|
|
|
mbio = bio_clone(bio, GFP_NOIO);
|
|
r1_bio->bios[i] = mbio;
|
|
|
|
mbio->bi_sector = r1_bio->sector + conf->mirrors[i].rdev->data_offset;
|
|
mbio->bi_bdev = conf->mirrors[i].rdev->bdev;
|
|
mbio->bi_end_io = raid1_end_write_request;
|
|
mbio->bi_rw = WRITE;
|
|
mbio->bi_private = r1_bio;
|
|
|
|
atomic_inc(&r1_bio->remaining);
|
|
generic_make_request(mbio);
|
|
}
|
|
|
|
if (atomic_dec_and_test(&r1_bio->remaining)) {
|
|
md_write_end(mddev);
|
|
raid_end_bio_io(r1_bio);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void status(struct seq_file *seq, mddev_t *mddev)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
int i;
|
|
|
|
seq_printf(seq, " [%d/%d] [", conf->raid_disks,
|
|
conf->working_disks);
|
|
for (i = 0; i < conf->raid_disks; i++)
|
|
seq_printf(seq, "%s",
|
|
conf->mirrors[i].rdev &&
|
|
conf->mirrors[i].rdev->in_sync ? "U" : "_");
|
|
seq_printf(seq, "]");
|
|
}
|
|
|
|
|
|
static void error(mddev_t *mddev, mdk_rdev_t *rdev)
|
|
{
|
|
char b[BDEVNAME_SIZE];
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
|
|
/*
|
|
* If it is not operational, then we have already marked it as dead
|
|
* else if it is the last working disks, ignore the error, let the
|
|
* next level up know.
|
|
* else mark the drive as failed
|
|
*/
|
|
if (rdev->in_sync
|
|
&& conf->working_disks == 1)
|
|
/*
|
|
* Don't fail the drive, act as though we were just a
|
|
* normal single drive
|
|
*/
|
|
return;
|
|
if (rdev->in_sync) {
|
|
mddev->degraded++;
|
|
conf->working_disks--;
|
|
/*
|
|
* if recovery is running, make sure it aborts.
|
|
*/
|
|
set_bit(MD_RECOVERY_ERR, &mddev->recovery);
|
|
}
|
|
rdev->in_sync = 0;
|
|
rdev->faulty = 1;
|
|
mddev->sb_dirty = 1;
|
|
printk(KERN_ALERT "raid1: Disk failure on %s, disabling device. \n"
|
|
" Operation continuing on %d devices\n",
|
|
bdevname(rdev->bdev,b), conf->working_disks);
|
|
}
|
|
|
|
static void print_conf(conf_t *conf)
|
|
{
|
|
int i;
|
|
mirror_info_t *tmp;
|
|
|
|
printk("RAID1 conf printout:\n");
|
|
if (!conf) {
|
|
printk("(!conf)\n");
|
|
return;
|
|
}
|
|
printk(" --- wd:%d rd:%d\n", conf->working_disks,
|
|
conf->raid_disks);
|
|
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
char b[BDEVNAME_SIZE];
|
|
tmp = conf->mirrors + i;
|
|
if (tmp->rdev)
|
|
printk(" disk %d, wo:%d, o:%d, dev:%s\n",
|
|
i, !tmp->rdev->in_sync, !tmp->rdev->faulty,
|
|
bdevname(tmp->rdev->bdev,b));
|
|
}
|
|
}
|
|
|
|
static void close_sync(conf_t *conf)
|
|
{
|
|
spin_lock_irq(&conf->resync_lock);
|
|
wait_event_lock_irq(conf->wait_resume, !conf->barrier,
|
|
conf->resync_lock, unplug_slaves(conf->mddev));
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
|
|
if (conf->barrier) BUG();
|
|
if (waitqueue_active(&conf->wait_idle)) BUG();
|
|
|
|
mempool_destroy(conf->r1buf_pool);
|
|
conf->r1buf_pool = NULL;
|
|
}
|
|
|
|
static int raid1_spare_active(mddev_t *mddev)
|
|
{
|
|
int i;
|
|
conf_t *conf = mddev->private;
|
|
mirror_info_t *tmp;
|
|
|
|
/*
|
|
* Find all failed disks within the RAID1 configuration
|
|
* and mark them readable
|
|
*/
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
tmp = conf->mirrors + i;
|
|
if (tmp->rdev
|
|
&& !tmp->rdev->faulty
|
|
&& !tmp->rdev->in_sync) {
|
|
conf->working_disks++;
|
|
mddev->degraded--;
|
|
tmp->rdev->in_sync = 1;
|
|
}
|
|
}
|
|
|
|
print_conf(conf);
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
|
|
{
|
|
conf_t *conf = mddev->private;
|
|
int found = 0;
|
|
int mirror;
|
|
mirror_info_t *p;
|
|
|
|
for (mirror=0; mirror < mddev->raid_disks; mirror++)
|
|
if ( !(p=conf->mirrors+mirror)->rdev) {
|
|
|
|
blk_queue_stack_limits(mddev->queue,
|
|
rdev->bdev->bd_disk->queue);
|
|
/* as we don't honour merge_bvec_fn, we must never risk
|
|
* violating it, so limit ->max_sector to one PAGE, as
|
|
* a one page request is never in violation.
|
|
*/
|
|
if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
|
|
mddev->queue->max_sectors > (PAGE_SIZE>>9))
|
|
blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
|
|
|
|
p->head_position = 0;
|
|
rdev->raid_disk = mirror;
|
|
found = 1;
|
|
p->rdev = rdev;
|
|
break;
|
|
}
|
|
|
|
print_conf(conf);
|
|
return found;
|
|
}
|
|
|
|
static int raid1_remove_disk(mddev_t *mddev, int number)
|
|
{
|
|
conf_t *conf = mddev->private;
|
|
int err = 0;
|
|
mdk_rdev_t *rdev;
|
|
mirror_info_t *p = conf->mirrors+ number;
|
|
|
|
print_conf(conf);
|
|
rdev = p->rdev;
|
|
if (rdev) {
|
|
if (rdev->in_sync ||
|
|
atomic_read(&rdev->nr_pending)) {
|
|
err = -EBUSY;
|
|
goto abort;
|
|
}
|
|
p->rdev = NULL;
|
|
synchronize_kernel();
|
|
if (atomic_read(&rdev->nr_pending)) {
|
|
/* lost the race, try later */
|
|
err = -EBUSY;
|
|
p->rdev = rdev;
|
|
}
|
|
}
|
|
abort:
|
|
|
|
print_conf(conf);
|
|
return err;
|
|
}
|
|
|
|
|
|
static int end_sync_read(struct bio *bio, unsigned int bytes_done, int error)
|
|
{
|
|
int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
|
|
r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
|
|
conf_t *conf = mddev_to_conf(r1_bio->mddev);
|
|
|
|
if (bio->bi_size)
|
|
return 1;
|
|
|
|
if (r1_bio->bios[r1_bio->read_disk] != bio)
|
|
BUG();
|
|
update_head_pos(r1_bio->read_disk, r1_bio);
|
|
/*
|
|
* we have read a block, now it needs to be re-written,
|
|
* or re-read if the read failed.
|
|
* We don't do much here, just schedule handling by raid1d
|
|
*/
|
|
if (!uptodate)
|
|
md_error(r1_bio->mddev,
|
|
conf->mirrors[r1_bio->read_disk].rdev);
|
|
else
|
|
set_bit(R1BIO_Uptodate, &r1_bio->state);
|
|
rdev_dec_pending(conf->mirrors[r1_bio->read_disk].rdev, conf->mddev);
|
|
reschedule_retry(r1_bio);
|
|
return 0;
|
|
}
|
|
|
|
static int end_sync_write(struct bio *bio, unsigned int bytes_done, int error)
|
|
{
|
|
int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
|
|
r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
|
|
mddev_t *mddev = r1_bio->mddev;
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
int i;
|
|
int mirror=0;
|
|
|
|
if (bio->bi_size)
|
|
return 1;
|
|
|
|
for (i = 0; i < conf->raid_disks; i++)
|
|
if (r1_bio->bios[i] == bio) {
|
|
mirror = i;
|
|
break;
|
|
}
|
|
if (!uptodate)
|
|
md_error(mddev, conf->mirrors[mirror].rdev);
|
|
update_head_pos(mirror, r1_bio);
|
|
|
|
if (atomic_dec_and_test(&r1_bio->remaining)) {
|
|
md_done_sync(mddev, r1_bio->sectors, uptodate);
|
|
put_buf(r1_bio);
|
|
}
|
|
rdev_dec_pending(conf->mirrors[mirror].rdev, mddev);
|
|
return 0;
|
|
}
|
|
|
|
static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
int i;
|
|
int disks = conf->raid_disks;
|
|
struct bio *bio, *wbio;
|
|
|
|
bio = r1_bio->bios[r1_bio->read_disk];
|
|
|
|
/*
|
|
* schedule writes
|
|
*/
|
|
if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
|
|
/*
|
|
* There is no point trying a read-for-reconstruct as
|
|
* reconstruct is about to be aborted
|
|
*/
|
|
char b[BDEVNAME_SIZE];
|
|
printk(KERN_ALERT "raid1: %s: unrecoverable I/O read error"
|
|
" for block %llu\n",
|
|
bdevname(bio->bi_bdev,b),
|
|
(unsigned long long)r1_bio->sector);
|
|
md_done_sync(mddev, r1_bio->sectors, 0);
|
|
put_buf(r1_bio);
|
|
return;
|
|
}
|
|
|
|
atomic_set(&r1_bio->remaining, 1);
|
|
for (i = 0; i < disks ; i++) {
|
|
wbio = r1_bio->bios[i];
|
|
if (wbio->bi_end_io != end_sync_write)
|
|
continue;
|
|
|
|
atomic_inc(&conf->mirrors[i].rdev->nr_pending);
|
|
atomic_inc(&r1_bio->remaining);
|
|
md_sync_acct(conf->mirrors[i].rdev->bdev, wbio->bi_size >> 9);
|
|
generic_make_request(wbio);
|
|
}
|
|
|
|
if (atomic_dec_and_test(&r1_bio->remaining)) {
|
|
md_done_sync(mddev, r1_bio->sectors, 1);
|
|
put_buf(r1_bio);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This is a kernel thread which:
|
|
*
|
|
* 1. Retries failed read operations on working mirrors.
|
|
* 2. Updates the raid superblock when problems encounter.
|
|
* 3. Performs writes following reads for array syncronising.
|
|
*/
|
|
|
|
static void raid1d(mddev_t *mddev)
|
|
{
|
|
r1bio_t *r1_bio;
|
|
struct bio *bio;
|
|
unsigned long flags;
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
struct list_head *head = &conf->retry_list;
|
|
int unplug=0;
|
|
mdk_rdev_t *rdev;
|
|
|
|
md_check_recovery(mddev);
|
|
md_handle_safemode(mddev);
|
|
|
|
for (;;) {
|
|
char b[BDEVNAME_SIZE];
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
if (list_empty(head))
|
|
break;
|
|
r1_bio = list_entry(head->prev, r1bio_t, retry_list);
|
|
list_del(head->prev);
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
|
|
mddev = r1_bio->mddev;
|
|
conf = mddev_to_conf(mddev);
|
|
if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
|
|
sync_request_write(mddev, r1_bio);
|
|
unplug = 1;
|
|
} else {
|
|
int disk;
|
|
bio = r1_bio->bios[r1_bio->read_disk];
|
|
if ((disk=read_balance(conf, r1_bio)) == -1) {
|
|
printk(KERN_ALERT "raid1: %s: unrecoverable I/O"
|
|
" read error for block %llu\n",
|
|
bdevname(bio->bi_bdev,b),
|
|
(unsigned long long)r1_bio->sector);
|
|
raid_end_bio_io(r1_bio);
|
|
} else {
|
|
r1_bio->bios[r1_bio->read_disk] = NULL;
|
|
r1_bio->read_disk = disk;
|
|
bio_put(bio);
|
|
bio = bio_clone(r1_bio->master_bio, GFP_NOIO);
|
|
r1_bio->bios[r1_bio->read_disk] = bio;
|
|
rdev = conf->mirrors[disk].rdev;
|
|
if (printk_ratelimit())
|
|
printk(KERN_ERR "raid1: %s: redirecting sector %llu to"
|
|
" another mirror\n",
|
|
bdevname(rdev->bdev,b),
|
|
(unsigned long long)r1_bio->sector);
|
|
bio->bi_sector = r1_bio->sector + rdev->data_offset;
|
|
bio->bi_bdev = rdev->bdev;
|
|
bio->bi_end_io = raid1_end_read_request;
|
|
bio->bi_rw = READ;
|
|
bio->bi_private = r1_bio;
|
|
unplug = 1;
|
|
generic_make_request(bio);
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
if (unplug)
|
|
unplug_slaves(mddev);
|
|
}
|
|
|
|
|
|
static int init_resync(conf_t *conf)
|
|
{
|
|
int buffs;
|
|
|
|
buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
|
|
if (conf->r1buf_pool)
|
|
BUG();
|
|
conf->r1buf_pool = mempool_create(buffs, r1buf_pool_alloc, r1buf_pool_free,
|
|
conf->poolinfo);
|
|
if (!conf->r1buf_pool)
|
|
return -ENOMEM;
|
|
conf->next_resync = 0;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* perform a "sync" on one "block"
|
|
*
|
|
* We need to make sure that no normal I/O request - particularly write
|
|
* requests - conflict with active sync requests.
|
|
*
|
|
* This is achieved by tracking pending requests and a 'barrier' concept
|
|
* that can be installed to exclude normal IO requests.
|
|
*/
|
|
|
|
static int sync_request(mddev_t *mddev, sector_t sector_nr, int go_faster)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
mirror_info_t *mirror;
|
|
r1bio_t *r1_bio;
|
|
struct bio *bio;
|
|
sector_t max_sector, nr_sectors;
|
|
int disk;
|
|
int i;
|
|
int write_targets = 0;
|
|
|
|
if (!conf->r1buf_pool)
|
|
if (init_resync(conf))
|
|
return -ENOMEM;
|
|
|
|
max_sector = mddev->size << 1;
|
|
if (sector_nr >= max_sector) {
|
|
close_sync(conf);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* If there is non-resync activity waiting for us then
|
|
* put in a delay to throttle resync.
|
|
*/
|
|
if (!go_faster && waitqueue_active(&conf->wait_resume))
|
|
msleep_interruptible(1000);
|
|
device_barrier(conf, sector_nr + RESYNC_SECTORS);
|
|
|
|
/*
|
|
* If reconstructing, and >1 working disc,
|
|
* could dedicate one to rebuild and others to
|
|
* service read requests ..
|
|
*/
|
|
disk = conf->last_used;
|
|
/* make sure disk is operational */
|
|
|
|
while (conf->mirrors[disk].rdev == NULL ||
|
|
!conf->mirrors[disk].rdev->in_sync) {
|
|
if (disk <= 0)
|
|
disk = conf->raid_disks;
|
|
disk--;
|
|
if (disk == conf->last_used)
|
|
break;
|
|
}
|
|
conf->last_used = disk;
|
|
atomic_inc(&conf->mirrors[disk].rdev->nr_pending);
|
|
|
|
|
|
mirror = conf->mirrors + disk;
|
|
|
|
r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO);
|
|
|
|
spin_lock_irq(&conf->resync_lock);
|
|
conf->nr_pending++;
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
|
|
r1_bio->mddev = mddev;
|
|
r1_bio->sector = sector_nr;
|
|
set_bit(R1BIO_IsSync, &r1_bio->state);
|
|
r1_bio->read_disk = disk;
|
|
|
|
for (i=0; i < conf->raid_disks; i++) {
|
|
bio = r1_bio->bios[i];
|
|
|
|
/* take from bio_init */
|
|
bio->bi_next = NULL;
|
|
bio->bi_flags |= 1 << BIO_UPTODATE;
|
|
bio->bi_rw = 0;
|
|
bio->bi_vcnt = 0;
|
|
bio->bi_idx = 0;
|
|
bio->bi_phys_segments = 0;
|
|
bio->bi_hw_segments = 0;
|
|
bio->bi_size = 0;
|
|
bio->bi_end_io = NULL;
|
|
bio->bi_private = NULL;
|
|
|
|
if (i == disk) {
|
|
bio->bi_rw = READ;
|
|
bio->bi_end_io = end_sync_read;
|
|
} else if (conf->mirrors[i].rdev &&
|
|
!conf->mirrors[i].rdev->faulty &&
|
|
(!conf->mirrors[i].rdev->in_sync ||
|
|
sector_nr + RESYNC_SECTORS > mddev->recovery_cp)) {
|
|
bio->bi_rw = WRITE;
|
|
bio->bi_end_io = end_sync_write;
|
|
write_targets ++;
|
|
} else
|
|
continue;
|
|
bio->bi_sector = sector_nr + conf->mirrors[i].rdev->data_offset;
|
|
bio->bi_bdev = conf->mirrors[i].rdev->bdev;
|
|
bio->bi_private = r1_bio;
|
|
}
|
|
if (write_targets == 0) {
|
|
/* There is nowhere to write, so all non-sync
|
|
* drives must be failed - so we are finished
|
|
*/
|
|
int rv = max_sector - sector_nr;
|
|
md_done_sync(mddev, rv, 1);
|
|
put_buf(r1_bio);
|
|
rdev_dec_pending(conf->mirrors[disk].rdev, mddev);
|
|
return rv;
|
|
}
|
|
|
|
nr_sectors = 0;
|
|
do {
|
|
struct page *page;
|
|
int len = PAGE_SIZE;
|
|
if (sector_nr + (len>>9) > max_sector)
|
|
len = (max_sector - sector_nr) << 9;
|
|
if (len == 0)
|
|
break;
|
|
for (i=0 ; i < conf->raid_disks; i++) {
|
|
bio = r1_bio->bios[i];
|
|
if (bio->bi_end_io) {
|
|
page = r1_bio->bios[0]->bi_io_vec[bio->bi_vcnt].bv_page;
|
|
if (bio_add_page(bio, page, len, 0) == 0) {
|
|
/* stop here */
|
|
r1_bio->bios[0]->bi_io_vec[bio->bi_vcnt].bv_page = page;
|
|
while (i > 0) {
|
|
i--;
|
|
bio = r1_bio->bios[i];
|
|
if (bio->bi_end_io==NULL) continue;
|
|
/* remove last page from this bio */
|
|
bio->bi_vcnt--;
|
|
bio->bi_size -= len;
|
|
bio->bi_flags &= ~(1<< BIO_SEG_VALID);
|
|
}
|
|
goto bio_full;
|
|
}
|
|
}
|
|
}
|
|
nr_sectors += len>>9;
|
|
sector_nr += len>>9;
|
|
} while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES);
|
|
bio_full:
|
|
bio = r1_bio->bios[disk];
|
|
r1_bio->sectors = nr_sectors;
|
|
|
|
md_sync_acct(mirror->rdev->bdev, nr_sectors);
|
|
|
|
generic_make_request(bio);
|
|
|
|
return nr_sectors;
|
|
}
|
|
|
|
static int run(mddev_t *mddev)
|
|
{
|
|
conf_t *conf;
|
|
int i, j, disk_idx;
|
|
mirror_info_t *disk;
|
|
mdk_rdev_t *rdev;
|
|
struct list_head *tmp;
|
|
|
|
if (mddev->level != 1) {
|
|
printk("raid1: %s: raid level not set to mirroring (%d)\n",
|
|
mdname(mddev), mddev->level);
|
|
goto out;
|
|
}
|
|
/*
|
|
* copy the already verified devices into our private RAID1
|
|
* bookkeeping area. [whatever we allocate in run(),
|
|
* should be freed in stop()]
|
|
*/
|
|
conf = kmalloc(sizeof(conf_t), GFP_KERNEL);
|
|
mddev->private = conf;
|
|
if (!conf)
|
|
goto out_no_mem;
|
|
|
|
memset(conf, 0, sizeof(*conf));
|
|
conf->mirrors = kmalloc(sizeof(struct mirror_info)*mddev->raid_disks,
|
|
GFP_KERNEL);
|
|
if (!conf->mirrors)
|
|
goto out_no_mem;
|
|
|
|
memset(conf->mirrors, 0, sizeof(struct mirror_info)*mddev->raid_disks);
|
|
|
|
conf->poolinfo = kmalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
|
|
if (!conf->poolinfo)
|
|
goto out_no_mem;
|
|
conf->poolinfo->mddev = mddev;
|
|
conf->poolinfo->raid_disks = mddev->raid_disks;
|
|
conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc,
|
|
r1bio_pool_free,
|
|
conf->poolinfo);
|
|
if (!conf->r1bio_pool)
|
|
goto out_no_mem;
|
|
|
|
mddev->queue->unplug_fn = raid1_unplug;
|
|
|
|
mddev->queue->issue_flush_fn = raid1_issue_flush;
|
|
|
|
ITERATE_RDEV(mddev, rdev, tmp) {
|
|
disk_idx = rdev->raid_disk;
|
|
if (disk_idx >= mddev->raid_disks
|
|
|| disk_idx < 0)
|
|
continue;
|
|
disk = conf->mirrors + disk_idx;
|
|
|
|
disk->rdev = rdev;
|
|
|
|
blk_queue_stack_limits(mddev->queue,
|
|
rdev->bdev->bd_disk->queue);
|
|
/* as we don't honour merge_bvec_fn, we must never risk
|
|
* violating it, so limit ->max_sector to one PAGE, as
|
|
* a one page request is never in violation.
|
|
*/
|
|
if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
|
|
mddev->queue->max_sectors > (PAGE_SIZE>>9))
|
|
blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
|
|
|
|
disk->head_position = 0;
|
|
if (!rdev->faulty && rdev->in_sync)
|
|
conf->working_disks++;
|
|
}
|
|
conf->raid_disks = mddev->raid_disks;
|
|
conf->mddev = mddev;
|
|
spin_lock_init(&conf->device_lock);
|
|
INIT_LIST_HEAD(&conf->retry_list);
|
|
if (conf->working_disks == 1)
|
|
mddev->recovery_cp = MaxSector;
|
|
|
|
spin_lock_init(&conf->resync_lock);
|
|
init_waitqueue_head(&conf->wait_idle);
|
|
init_waitqueue_head(&conf->wait_resume);
|
|
|
|
if (!conf->working_disks) {
|
|
printk(KERN_ERR "raid1: no operational mirrors for %s\n",
|
|
mdname(mddev));
|
|
goto out_free_conf;
|
|
}
|
|
|
|
mddev->degraded = 0;
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
|
|
disk = conf->mirrors + i;
|
|
|
|
if (!disk->rdev) {
|
|
disk->head_position = 0;
|
|
mddev->degraded++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* find the first working one and use it as a starting point
|
|
* to read balancing.
|
|
*/
|
|
for (j = 0; j < conf->raid_disks &&
|
|
(!conf->mirrors[j].rdev ||
|
|
!conf->mirrors[j].rdev->in_sync) ; j++)
|
|
/* nothing */;
|
|
conf->last_used = j;
|
|
|
|
|
|
|
|
{
|
|
mddev->thread = md_register_thread(raid1d, mddev, "%s_raid1");
|
|
if (!mddev->thread) {
|
|
printk(KERN_ERR
|
|
"raid1: couldn't allocate thread for %s\n",
|
|
mdname(mddev));
|
|
goto out_free_conf;
|
|
}
|
|
}
|
|
printk(KERN_INFO
|
|
"raid1: raid set %s active with %d out of %d mirrors\n",
|
|
mdname(mddev), mddev->raid_disks - mddev->degraded,
|
|
mddev->raid_disks);
|
|
/*
|
|
* Ok, everything is just fine now
|
|
*/
|
|
mddev->array_size = mddev->size;
|
|
|
|
return 0;
|
|
|
|
out_no_mem:
|
|
printk(KERN_ERR "raid1: couldn't allocate memory for %s\n",
|
|
mdname(mddev));
|
|
|
|
out_free_conf:
|
|
if (conf) {
|
|
if (conf->r1bio_pool)
|
|
mempool_destroy(conf->r1bio_pool);
|
|
if (conf->mirrors)
|
|
kfree(conf->mirrors);
|
|
if (conf->poolinfo)
|
|
kfree(conf->poolinfo);
|
|
kfree(conf);
|
|
mddev->private = NULL;
|
|
}
|
|
out:
|
|
return -EIO;
|
|
}
|
|
|
|
static int stop(mddev_t *mddev)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
|
|
md_unregister_thread(mddev->thread);
|
|
mddev->thread = NULL;
|
|
blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
|
|
if (conf->r1bio_pool)
|
|
mempool_destroy(conf->r1bio_pool);
|
|
if (conf->mirrors)
|
|
kfree(conf->mirrors);
|
|
if (conf->poolinfo)
|
|
kfree(conf->poolinfo);
|
|
kfree(conf);
|
|
mddev->private = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static int raid1_resize(mddev_t *mddev, sector_t sectors)
|
|
{
|
|
/* no resync is happening, and there is enough space
|
|
* on all devices, so we can resize.
|
|
* We need to make sure resync covers any new space.
|
|
* If the array is shrinking we should possibly wait until
|
|
* any io in the removed space completes, but it hardly seems
|
|
* worth it.
|
|
*/
|
|
mddev->array_size = sectors>>1;
|
|
set_capacity(mddev->gendisk, mddev->array_size << 1);
|
|
mddev->changed = 1;
|
|
if (mddev->array_size > mddev->size && mddev->recovery_cp == MaxSector) {
|
|
mddev->recovery_cp = mddev->size << 1;
|
|
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
|
|
}
|
|
mddev->size = mddev->array_size;
|
|
return 0;
|
|
}
|
|
|
|
static int raid1_reshape(mddev_t *mddev, int raid_disks)
|
|
{
|
|
/* We need to:
|
|
* 1/ resize the r1bio_pool
|
|
* 2/ resize conf->mirrors
|
|
*
|
|
* We allocate a new r1bio_pool if we can.
|
|
* Then raise a device barrier and wait until all IO stops.
|
|
* Then resize conf->mirrors and swap in the new r1bio pool.
|
|
*/
|
|
mempool_t *newpool, *oldpool;
|
|
struct pool_info *newpoolinfo;
|
|
mirror_info_t *newmirrors;
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
|
|
int d;
|
|
|
|
for (d= raid_disks; d < conf->raid_disks; d++)
|
|
if (conf->mirrors[d].rdev)
|
|
return -EBUSY;
|
|
|
|
newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
|
|
if (!newpoolinfo)
|
|
return -ENOMEM;
|
|
newpoolinfo->mddev = mddev;
|
|
newpoolinfo->raid_disks = raid_disks;
|
|
|
|
newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc,
|
|
r1bio_pool_free, newpoolinfo);
|
|
if (!newpool) {
|
|
kfree(newpoolinfo);
|
|
return -ENOMEM;
|
|
}
|
|
newmirrors = kmalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL);
|
|
if (!newmirrors) {
|
|
kfree(newpoolinfo);
|
|
mempool_destroy(newpool);
|
|
return -ENOMEM;
|
|
}
|
|
memset(newmirrors, 0, sizeof(struct mirror_info)*raid_disks);
|
|
|
|
spin_lock_irq(&conf->resync_lock);
|
|
conf->barrier++;
|
|
wait_event_lock_irq(conf->wait_idle, !conf->nr_pending,
|
|
conf->resync_lock, unplug_slaves(mddev));
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
|
|
/* ok, everything is stopped */
|
|
oldpool = conf->r1bio_pool;
|
|
conf->r1bio_pool = newpool;
|
|
for (d=0; d < raid_disks && d < conf->raid_disks; d++)
|
|
newmirrors[d] = conf->mirrors[d];
|
|
kfree(conf->mirrors);
|
|
conf->mirrors = newmirrors;
|
|
kfree(conf->poolinfo);
|
|
conf->poolinfo = newpoolinfo;
|
|
|
|
mddev->degraded += (raid_disks - conf->raid_disks);
|
|
conf->raid_disks = mddev->raid_disks = raid_disks;
|
|
|
|
spin_lock_irq(&conf->resync_lock);
|
|
conf->barrier--;
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
wake_up(&conf->wait_resume);
|
|
wake_up(&conf->wait_idle);
|
|
|
|
|
|
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
|
|
md_wakeup_thread(mddev->thread);
|
|
|
|
mempool_destroy(oldpool);
|
|
return 0;
|
|
}
|
|
|
|
|
|
static mdk_personality_t raid1_personality =
|
|
{
|
|
.name = "raid1",
|
|
.owner = THIS_MODULE,
|
|
.make_request = make_request,
|
|
.run = run,
|
|
.stop = stop,
|
|
.status = status,
|
|
.error_handler = error,
|
|
.hot_add_disk = raid1_add_disk,
|
|
.hot_remove_disk= raid1_remove_disk,
|
|
.spare_active = raid1_spare_active,
|
|
.sync_request = sync_request,
|
|
.resize = raid1_resize,
|
|
.reshape = raid1_reshape,
|
|
};
|
|
|
|
static int __init raid_init(void)
|
|
{
|
|
return register_md_personality(RAID1, &raid1_personality);
|
|
}
|
|
|
|
static void raid_exit(void)
|
|
{
|
|
unregister_md_personality(RAID1);
|
|
}
|
|
|
|
module_init(raid_init);
|
|
module_exit(raid_exit);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("md-personality-3"); /* RAID1 */
|