![Tejun Heo](/assets/img/avatar_default.png)
Move stats related fields - stamp, in_flight, dkstats - from disk to part0 and unify stat handling such that... * part_stat_*() now updates part0 together if the specified partition is not part0. ie. part_stat_*() are now essentially all_stat_*(). * {disk|all}_stat_*() are gone. * part_round_stats() is updated similary. It handles part0 stats automatically and disk_round_stats() is killed. * part_{inc|dec}_in_fligh() is implemented which automatically updates part0 stats for parts other than part0. * disk_map_sector_rcu() is updated to return part0 if no part matches. Combined with the above changes, this makes NULL special case handling in callers unnecessary. * Separate stats show code paths for disk are collapsed into part stats show code paths. * Rename disk_stat_lock/unlock() to part_stat_lock/unlock() While at it, reposition stat handling macros a bit and add missing parentheses around macro parameters. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2281 lines
60 KiB
C
2281 lines
60 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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* Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
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* bitmapped intelligence in resync:
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*
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* - bitmap marked during normal i/o
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* - bitmap used to skip nondirty blocks during sync
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*
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* Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
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* - persistent bitmap code
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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 "dm-bio-list.h"
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#include <linux/raid/raid1.h>
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#include <linux/raid/bitmap.h>
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#define DEBUG 0
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#if DEBUG
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#define PRINTK(x...) printk(x)
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#else
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#define PRINTK(x...)
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#endif
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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 void unplug_slaves(mddev_t *mddev);
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static void allow_barrier(conf_t *conf);
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static void lower_barrier(conf_t *conf);
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static void * r1bio_pool_alloc(gfp_t 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 = kzalloc(size, gfp_flags);
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if (!r1_bio)
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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(gfp_t 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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* If this is a user-requested check/repair, allocate
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* RESYNC_PAGES for each bio.
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*/
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if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
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j = pi->raid_disks;
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else
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j = 1;
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while(j--) {
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bio = r1_bio->bios[j];
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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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}
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/* If not user-requests, copy the page pointers to all bios */
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if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) {
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for (i=0; i<RESYNC_PAGES ; i++)
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for (j=1; j<pi->raid_disks; j++)
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r1_bio->bios[j]->bi_io_vec[i].bv_page =
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r1_bio->bios[0]->bi_io_vec[i].bv_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 < RESYNC_PAGES ; i++)
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for (j=0 ; j < pi->raid_disks; j++)
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safe_put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);
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j = -1;
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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,j;
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r1bio_t *r1bio = __r1_bio;
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for (i = 0; i < RESYNC_PAGES; i++)
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for (j = pi->raid_disks; j-- ;) {
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if (j == 0 ||
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r1bio->bios[j]->bi_io_vec[i].bv_page !=
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r1bio->bios[0]->bi_io_vec[i].bv_page)
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safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page);
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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 && *bio != IO_BLOCKED)
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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 void free_r1bio(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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/*
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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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allow_barrier(conf);
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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 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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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->bi_end_io)
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rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
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}
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mempool_free(r1_bio, conf->r1buf_pool);
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lower_barrier(conf);
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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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conf->nr_queued ++;
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spin_unlock_irqrestore(&conf->device_lock, flags);
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wake_up(&conf->wait_barrier);
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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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/* if nobody has done the final endio yet, do it now */
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if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
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PRINTK(KERN_DEBUG "raid1: sync end %s on sectors %llu-%llu\n",
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(bio_data_dir(bio) == WRITE) ? "write" : "read",
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(unsigned long long) bio->bi_sector,
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(unsigned long long) bio->bi_sector +
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(bio->bi_size >> 9) - 1);
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bio_endio(bio,
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test_bit(R1BIO_Uptodate, &r1_bio->state) ? 0 : -EIO);
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}
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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 void raid1_end_read_request(struct bio *bio, 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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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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update_head_pos(mirror, r1_bio);
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if (uptodate)
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set_bit(R1BIO_Uptodate, &r1_bio->state);
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else {
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/* If all other devices have failed, we want to return
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* the error upwards rather than fail the last device.
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* Here we redefine "uptodate" to mean "Don't want to retry"
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*/
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unsigned long flags;
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spin_lock_irqsave(&conf->device_lock, flags);
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if (r1_bio->mddev->degraded == conf->raid_disks ||
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(r1_bio->mddev->degraded == conf->raid_disks-1 &&
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!test_bit(Faulty, &conf->mirrors[mirror].rdev->flags)))
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uptodate = 1;
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spin_unlock_irqrestore(&conf->device_lock, flags);
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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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}
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static void raid1_end_write_request(struct bio *bio, 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, behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
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conf_t *conf = mddev_to_conf(r1_bio->mddev);
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struct bio *to_put = NULL;
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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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if (error == -EOPNOTSUPP && test_bit(R1BIO_Barrier, &r1_bio->state)) {
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set_bit(BarriersNotsupp, &conf->mirrors[mirror].rdev->flags);
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set_bit(R1BIO_BarrierRetry, &r1_bio->state);
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r1_bio->mddev->barriers_work = 0;
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/* Don't rdev_dec_pending in this branch - keep it for the retry */
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} else {
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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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r1_bio->bios[mirror] = NULL;
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to_put = bio;
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if (!uptodate) {
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md_error(r1_bio->mddev, conf->mirrors[mirror].rdev);
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/* an I/O failed, we can't clear the bitmap */
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set_bit(R1BIO_Degraded, &r1_bio->state);
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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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if (behind) {
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if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags))
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atomic_dec(&r1_bio->behind_remaining);
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/* In behind mode, we ACK the master bio once the I/O has safely
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* reached all non-writemostly disks. Setting the Returned bit
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* ensures that this gets done only once -- we don't ever want to
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* return -EIO here, instead we'll wait */
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if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) &&
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test_bit(R1BIO_Uptodate, &r1_bio->state)) {
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/* Maybe we can return now */
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if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
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struct bio *mbio = r1_bio->master_bio;
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PRINTK(KERN_DEBUG "raid1: behind end write sectors %llu-%llu\n",
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(unsigned long long) mbio->bi_sector,
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(unsigned long long) mbio->bi_sector +
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(mbio->bi_size >> 9) - 1);
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bio_endio(mbio, 0);
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}
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}
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}
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rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);
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}
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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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if (test_bit(R1BIO_BarrierRetry, &r1_bio->state))
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reschedule_retry(r1_bio);
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else {
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/* it really is the end of this request */
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if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
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/* free extra copy of the data pages */
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int i = bio->bi_vcnt;
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while (i--)
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safe_put_page(bio->bi_io_vec[i].bv_page);
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}
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/* clear the bitmap if all writes complete successfully */
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bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
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r1_bio->sectors,
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!test_bit(R1BIO_Degraded, &r1_bio->state),
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behind);
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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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}
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if (to_put)
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bio_put(to_put);
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}
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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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int wonly_disk = -1;
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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 *rdev;
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|
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rcu_read_lock();
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/*
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* Check 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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for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
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r1_bio->bios[new_disk] == IO_BLOCKED ||
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!rdev || !test_bit(In_sync, &rdev->flags)
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|| test_bit(WriteMostly, &rdev->flags);
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rdev = rcu_dereference(conf->mirrors[++new_disk].rdev)) {
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if (rdev && test_bit(In_sync, &rdev->flags) &&
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r1_bio->bios[new_disk] != IO_BLOCKED)
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wonly_disk = new_disk;
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|
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if (new_disk == conf->raid_disks - 1) {
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new_disk = wonly_disk;
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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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|
|
|
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/* make sure the disk is operational */
|
|
for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
|
|
r1_bio->bios[new_disk] == IO_BLOCKED ||
|
|
!rdev || !test_bit(In_sync, &rdev->flags) ||
|
|
test_bit(WriteMostly, &rdev->flags);
|
|
rdev = rcu_dereference(conf->mirrors[new_disk].rdev)) {
|
|
|
|
if (rdev && test_bit(In_sync, &rdev->flags) &&
|
|
r1_bio->bios[new_disk] != IO_BLOCKED)
|
|
wonly_disk = new_disk;
|
|
|
|
if (new_disk <= 0)
|
|
new_disk = conf->raid_disks;
|
|
new_disk--;
|
|
if (new_disk == disk) {
|
|
new_disk = wonly_disk;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (new_disk < 0)
|
|
goto rb_out;
|
|
|
|
disk = new_disk;
|
|
/* now disk == new_disk == starting point for search */
|
|
|
|
/*
|
|
* Don't change to another disk for sequential reads:
|
|
*/
|
|
if (conf->next_seq_sect == this_sector)
|
|
goto rb_out;
|
|
if (this_sector == conf->mirrors[new_disk].head_position)
|
|
goto rb_out;
|
|
|
|
current_distance = abs(this_sector - conf->mirrors[disk].head_position);
|
|
|
|
/* Find the disk whose head is closest */
|
|
|
|
do {
|
|
if (disk <= 0)
|
|
disk = conf->raid_disks;
|
|
disk--;
|
|
|
|
rdev = rcu_dereference(conf->mirrors[disk].rdev);
|
|
|
|
if (!rdev || r1_bio->bios[disk] == IO_BLOCKED ||
|
|
!test_bit(In_sync, &rdev->flags) ||
|
|
test_bit(WriteMostly, &rdev->flags))
|
|
continue;
|
|
|
|
if (!atomic_read(&rdev->nr_pending)) {
|
|
new_disk = disk;
|
|
break;
|
|
}
|
|
new_distance = abs(this_sector - conf->mirrors[disk].head_position);
|
|
if (new_distance < current_distance) {
|
|
current_distance = new_distance;
|
|
new_disk = disk;
|
|
}
|
|
} while (disk != conf->last_used);
|
|
|
|
rb_out:
|
|
|
|
|
|
if (new_disk >= 0) {
|
|
rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
|
|
if (!rdev)
|
|
goto retry;
|
|
atomic_inc(&rdev->nr_pending);
|
|
if (!test_bit(In_sync, &rdev->flags)) {
|
|
/* cannot risk returning a device that failed
|
|
* before we inc'ed nr_pending
|
|
*/
|
|
rdev_dec_pending(rdev, conf->mddev);
|
|
goto retry;
|
|
}
|
|
conf->next_seq_sect = this_sector + sectors;
|
|
conf->last_used = new_disk;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return new_disk;
|
|
}
|
|
|
|
static void unplug_slaves(mddev_t *mddev)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
int i;
|
|
|
|
rcu_read_lock();
|
|
for (i=0; i<mddev->raid_disks; i++) {
|
|
mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
|
|
if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
|
|
struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
|
|
|
|
atomic_inc(&rdev->nr_pending);
|
|
rcu_read_unlock();
|
|
|
|
blk_unplug(r_queue);
|
|
|
|
rdev_dec_pending(rdev, mddev);
|
|
rcu_read_lock();
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static void raid1_unplug(struct request_queue *q)
|
|
{
|
|
mddev_t *mddev = q->queuedata;
|
|
|
|
unplug_slaves(mddev);
|
|
md_wakeup_thread(mddev->thread);
|
|
}
|
|
|
|
static int raid1_congested(void *data, int bits)
|
|
{
|
|
mddev_t *mddev = data;
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
int i, ret = 0;
|
|
|
|
rcu_read_lock();
|
|
for (i = 0; i < mddev->raid_disks; i++) {
|
|
mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
|
|
if (rdev && !test_bit(Faulty, &rdev->flags)) {
|
|
struct request_queue *q = bdev_get_queue(rdev->bdev);
|
|
|
|
/* Note the '|| 1' - when read_balance prefers
|
|
* non-congested targets, it can be removed
|
|
*/
|
|
if ((bits & (1<<BDI_write_congested)) || 1)
|
|
ret |= bdi_congested(&q->backing_dev_info, bits);
|
|
else
|
|
ret &= bdi_congested(&q->backing_dev_info, bits);
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
|
|
static int flush_pending_writes(conf_t *conf)
|
|
{
|
|
/* Any writes that have been queued but are awaiting
|
|
* bitmap updates get flushed here.
|
|
* We return 1 if any requests were actually submitted.
|
|
*/
|
|
int rv = 0;
|
|
|
|
spin_lock_irq(&conf->device_lock);
|
|
|
|
if (conf->pending_bio_list.head) {
|
|
struct bio *bio;
|
|
bio = bio_list_get(&conf->pending_bio_list);
|
|
blk_remove_plug(conf->mddev->queue);
|
|
spin_unlock_irq(&conf->device_lock);
|
|
/* flush any pending bitmap writes to
|
|
* disk before proceeding w/ I/O */
|
|
bitmap_unplug(conf->mddev->bitmap);
|
|
|
|
while (bio) { /* submit pending writes */
|
|
struct bio *next = bio->bi_next;
|
|
bio->bi_next = NULL;
|
|
generic_make_request(bio);
|
|
bio = next;
|
|
}
|
|
rv = 1;
|
|
} else
|
|
spin_unlock_irq(&conf->device_lock);
|
|
return rv;
|
|
}
|
|
|
|
/* Barriers....
|
|
* Sometimes we need to suspend IO while we do something else,
|
|
* either some resync/recovery, or reconfigure the array.
|
|
* To do this we raise a 'barrier'.
|
|
* The 'barrier' is a counter that can be raised multiple times
|
|
* to count how many activities are happening which preclude
|
|
* normal IO.
|
|
* We can only raise the barrier if there is no pending IO.
|
|
* i.e. if nr_pending == 0.
|
|
* We choose only to raise the barrier if no-one is waiting for the
|
|
* barrier to go down. This means that as soon as an IO request
|
|
* is ready, no other operations which require a barrier will start
|
|
* until the IO request has had a chance.
|
|
*
|
|
* So: regular IO calls 'wait_barrier'. When that returns there
|
|
* is no backgroup IO happening, It must arrange to call
|
|
* allow_barrier when it has finished its IO.
|
|
* backgroup IO calls must call raise_barrier. Once that returns
|
|
* there is no normal IO happeing. It must arrange to call
|
|
* lower_barrier when the particular background IO completes.
|
|
*/
|
|
#define RESYNC_DEPTH 32
|
|
|
|
static void raise_barrier(conf_t *conf)
|
|
{
|
|
spin_lock_irq(&conf->resync_lock);
|
|
|
|
/* Wait until no block IO is waiting */
|
|
wait_event_lock_irq(conf->wait_barrier, !conf->nr_waiting,
|
|
conf->resync_lock,
|
|
raid1_unplug(conf->mddev->queue));
|
|
|
|
/* block any new IO from starting */
|
|
conf->barrier++;
|
|
|
|
/* No wait for all pending IO to complete */
|
|
wait_event_lock_irq(conf->wait_barrier,
|
|
!conf->nr_pending && conf->barrier < RESYNC_DEPTH,
|
|
conf->resync_lock,
|
|
raid1_unplug(conf->mddev->queue));
|
|
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
}
|
|
|
|
static void lower_barrier(conf_t *conf)
|
|
{
|
|
unsigned long flags;
|
|
spin_lock_irqsave(&conf->resync_lock, flags);
|
|
conf->barrier--;
|
|
spin_unlock_irqrestore(&conf->resync_lock, flags);
|
|
wake_up(&conf->wait_barrier);
|
|
}
|
|
|
|
static void wait_barrier(conf_t *conf)
|
|
{
|
|
spin_lock_irq(&conf->resync_lock);
|
|
if (conf->barrier) {
|
|
conf->nr_waiting++;
|
|
wait_event_lock_irq(conf->wait_barrier, !conf->barrier,
|
|
conf->resync_lock,
|
|
raid1_unplug(conf->mddev->queue));
|
|
conf->nr_waiting--;
|
|
}
|
|
conf->nr_pending++;
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
}
|
|
|
|
static void allow_barrier(conf_t *conf)
|
|
{
|
|
unsigned long flags;
|
|
spin_lock_irqsave(&conf->resync_lock, flags);
|
|
conf->nr_pending--;
|
|
spin_unlock_irqrestore(&conf->resync_lock, flags);
|
|
wake_up(&conf->wait_barrier);
|
|
}
|
|
|
|
static void freeze_array(conf_t *conf)
|
|
{
|
|
/* stop syncio and normal IO and wait for everything to
|
|
* go quite.
|
|
* We increment barrier and nr_waiting, and then
|
|
* wait until nr_pending match nr_queued+1
|
|
* This is called in the context of one normal IO request
|
|
* that has failed. Thus any sync request that might be pending
|
|
* will be blocked by nr_pending, and we need to wait for
|
|
* pending IO requests to complete or be queued for re-try.
|
|
* Thus the number queued (nr_queued) plus this request (1)
|
|
* must match the number of pending IOs (nr_pending) before
|
|
* we continue.
|
|
*/
|
|
spin_lock_irq(&conf->resync_lock);
|
|
conf->barrier++;
|
|
conf->nr_waiting++;
|
|
wait_event_lock_irq(conf->wait_barrier,
|
|
conf->nr_pending == conf->nr_queued+1,
|
|
conf->resync_lock,
|
|
({ flush_pending_writes(conf);
|
|
raid1_unplug(conf->mddev->queue); }));
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
}
|
|
static void unfreeze_array(conf_t *conf)
|
|
{
|
|
/* reverse the effect of the freeze */
|
|
spin_lock_irq(&conf->resync_lock);
|
|
conf->barrier--;
|
|
conf->nr_waiting--;
|
|
wake_up(&conf->wait_barrier);
|
|
spin_unlock_irq(&conf->resync_lock);
|
|
}
|
|
|
|
|
|
/* duplicate the data pages for behind I/O */
|
|
static struct page **alloc_behind_pages(struct bio *bio)
|
|
{
|
|
int i;
|
|
struct bio_vec *bvec;
|
|
struct page **pages = kzalloc(bio->bi_vcnt * sizeof(struct page *),
|
|
GFP_NOIO);
|
|
if (unlikely(!pages))
|
|
goto do_sync_io;
|
|
|
|
bio_for_each_segment(bvec, bio, i) {
|
|
pages[i] = alloc_page(GFP_NOIO);
|
|
if (unlikely(!pages[i]))
|
|
goto do_sync_io;
|
|
memcpy(kmap(pages[i]) + bvec->bv_offset,
|
|
kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len);
|
|
kunmap(pages[i]);
|
|
kunmap(bvec->bv_page);
|
|
}
|
|
|
|
return pages;
|
|
|
|
do_sync_io:
|
|
if (pages)
|
|
for (i = 0; i < bio->bi_vcnt && pages[i]; i++)
|
|
put_page(pages[i]);
|
|
kfree(pages);
|
|
PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size);
|
|
return NULL;
|
|
}
|
|
|
|
static int make_request(struct request_queue *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, targets = 0, disks;
|
|
struct bitmap *bitmap;
|
|
unsigned long flags;
|
|
struct bio_list bl;
|
|
struct page **behind_pages = NULL;
|
|
const int rw = bio_data_dir(bio);
|
|
const int do_sync = bio_sync(bio);
|
|
int cpu, do_barriers;
|
|
mdk_rdev_t *blocked_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.
|
|
* We test barriers_work *after* md_write_start as md_write_start
|
|
* may cause the first superblock write, and that will check out
|
|
* if barriers work.
|
|
*/
|
|
|
|
md_write_start(mddev, bio); /* wait on superblock update early */
|
|
|
|
if (unlikely(!mddev->barriers_work && bio_barrier(bio))) {
|
|
if (rw == WRITE)
|
|
md_write_end(mddev);
|
|
bio_endio(bio, -EOPNOTSUPP);
|
|
return 0;
|
|
}
|
|
|
|
wait_barrier(conf);
|
|
|
|
bitmap = mddev->bitmap;
|
|
|
|
cpu = part_stat_lock();
|
|
part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
|
|
part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw],
|
|
bio_sectors(bio));
|
|
part_stat_unlock();
|
|
|
|
/*
|
|
* 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->state = 0;
|
|
r1_bio->mddev = mddev;
|
|
r1_bio->sector = bio->bi_sector;
|
|
|
|
if (rw == 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 | do_sync;
|
|
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;
|
|
#if 0
|
|
{ static int first=1;
|
|
if (first) printk("First Write sector %llu disks %d\n",
|
|
(unsigned long long)r1_bio->sector, disks);
|
|
first = 0;
|
|
}
|
|
#endif
|
|
retry_write:
|
|
blocked_rdev = NULL;
|
|
rcu_read_lock();
|
|
for (i = 0; i < disks; i++) {
|
|
mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
|
|
if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
|
|
atomic_inc(&rdev->nr_pending);
|
|
blocked_rdev = rdev;
|
|
break;
|
|
}
|
|
if (rdev && !test_bit(Faulty, &rdev->flags)) {
|
|
atomic_inc(&rdev->nr_pending);
|
|
if (test_bit(Faulty, &rdev->flags)) {
|
|
rdev_dec_pending(rdev, mddev);
|
|
r1_bio->bios[i] = NULL;
|
|
} else
|
|
r1_bio->bios[i] = bio;
|
|
targets++;
|
|
} else
|
|
r1_bio->bios[i] = NULL;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (unlikely(blocked_rdev)) {
|
|
/* Wait for this device to become unblocked */
|
|
int j;
|
|
|
|
for (j = 0; j < i; j++)
|
|
if (r1_bio->bios[j])
|
|
rdev_dec_pending(conf->mirrors[j].rdev, mddev);
|
|
|
|
allow_barrier(conf);
|
|
md_wait_for_blocked_rdev(blocked_rdev, mddev);
|
|
wait_barrier(conf);
|
|
goto retry_write;
|
|
}
|
|
|
|
BUG_ON(targets == 0); /* we never fail the last device */
|
|
|
|
if (targets < conf->raid_disks) {
|
|
/* array is degraded, we will not clear the bitmap
|
|
* on I/O completion (see raid1_end_write_request) */
|
|
set_bit(R1BIO_Degraded, &r1_bio->state);
|
|
}
|
|
|
|
/* do behind I/O ? */
|
|
if (bitmap &&
|
|
atomic_read(&bitmap->behind_writes) < bitmap->max_write_behind &&
|
|
(behind_pages = alloc_behind_pages(bio)) != NULL)
|
|
set_bit(R1BIO_BehindIO, &r1_bio->state);
|
|
|
|
atomic_set(&r1_bio->remaining, 0);
|
|
atomic_set(&r1_bio->behind_remaining, 0);
|
|
|
|
do_barriers = bio_barrier(bio);
|
|
if (do_barriers)
|
|
set_bit(R1BIO_Barrier, &r1_bio->state);
|
|
|
|
bio_list_init(&bl);
|
|
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 | do_barriers | do_sync;
|
|
mbio->bi_private = r1_bio;
|
|
|
|
if (behind_pages) {
|
|
struct bio_vec *bvec;
|
|
int j;
|
|
|
|
/* Yes, I really want the '__' version so that
|
|
* we clear any unused pointer in the io_vec, rather
|
|
* than leave them unchanged. This is important
|
|
* because when we come to free the pages, we won't
|
|
* know the originial bi_idx, so we just free
|
|
* them all
|
|
*/
|
|
__bio_for_each_segment(bvec, mbio, j, 0)
|
|
bvec->bv_page = behind_pages[j];
|
|
if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags))
|
|
atomic_inc(&r1_bio->behind_remaining);
|
|
}
|
|
|
|
atomic_inc(&r1_bio->remaining);
|
|
|
|
bio_list_add(&bl, mbio);
|
|
}
|
|
kfree(behind_pages); /* the behind pages are attached to the bios now */
|
|
|
|
bitmap_startwrite(bitmap, bio->bi_sector, r1_bio->sectors,
|
|
test_bit(R1BIO_BehindIO, &r1_bio->state));
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
bio_list_merge(&conf->pending_bio_list, &bl);
|
|
bio_list_init(&bl);
|
|
|
|
blk_plug_device(mddev->queue);
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
|
|
/* In case raid1d snuck into freeze_array */
|
|
wake_up(&conf->wait_barrier);
|
|
|
|
if (do_sync)
|
|
md_wakeup_thread(mddev->thread);
|
|
#if 0
|
|
while ((bio = bio_list_pop(&bl)) != NULL)
|
|
generic_make_request(bio);
|
|
#endif
|
|
|
|
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->raid_disks - mddev->degraded);
|
|
rcu_read_lock();
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
|
|
seq_printf(seq, "%s",
|
|
rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
|
|
}
|
|
rcu_read_unlock();
|
|
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 (test_bit(In_sync, &rdev->flags)
|
|
&& (conf->raid_disks - mddev->degraded) == 1)
|
|
/*
|
|
* Don't fail the drive, act as though we were just a
|
|
* normal single drive
|
|
*/
|
|
return;
|
|
if (test_and_clear_bit(In_sync, &rdev->flags)) {
|
|
unsigned long flags;
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
mddev->degraded++;
|
|
set_bit(Faulty, &rdev->flags);
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
/*
|
|
* if recovery is running, make sure it aborts.
|
|
*/
|
|
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
|
|
} else
|
|
set_bit(Faulty, &rdev->flags);
|
|
set_bit(MD_CHANGE_DEVS, &mddev->flags);
|
|
printk(KERN_ALERT "raid1: Disk failure on %s, disabling device.\n"
|
|
"raid1: Operation continuing on %d devices.\n",
|
|
bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded);
|
|
}
|
|
|
|
static void print_conf(conf_t *conf)
|
|
{
|
|
int i;
|
|
|
|
printk("RAID1 conf printout:\n");
|
|
if (!conf) {
|
|
printk("(!conf)\n");
|
|
return;
|
|
}
|
|
printk(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
|
|
conf->raid_disks);
|
|
|
|
rcu_read_lock();
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
char b[BDEVNAME_SIZE];
|
|
mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
|
|
if (rdev)
|
|
printk(" disk %d, wo:%d, o:%d, dev:%s\n",
|
|
i, !test_bit(In_sync, &rdev->flags),
|
|
!test_bit(Faulty, &rdev->flags),
|
|
bdevname(rdev->bdev,b));
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static void close_sync(conf_t *conf)
|
|
{
|
|
wait_barrier(conf);
|
|
allow_barrier(conf);
|
|
|
|
mempool_destroy(conf->r1buf_pool);
|
|
conf->r1buf_pool = NULL;
|
|
}
|
|
|
|
static int raid1_spare_active(mddev_t *mddev)
|
|
{
|
|
int i;
|
|
conf_t *conf = mddev->private;
|
|
|
|
/*
|
|
* Find all failed disks within the RAID1 configuration
|
|
* and mark them readable.
|
|
* Called under mddev lock, so rcu protection not needed.
|
|
*/
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
mdk_rdev_t *rdev = conf->mirrors[i].rdev;
|
|
if (rdev
|
|
&& !test_bit(Faulty, &rdev->flags)
|
|
&& !test_and_set_bit(In_sync, &rdev->flags)) {
|
|
unsigned long flags;
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
mddev->degraded--;
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
}
|
|
}
|
|
|
|
print_conf(conf);
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
|
|
{
|
|
conf_t *conf = mddev->private;
|
|
int err = -EEXIST;
|
|
int mirror = 0;
|
|
mirror_info_t *p;
|
|
int first = 0;
|
|
int last = mddev->raid_disks - 1;
|
|
|
|
if (rdev->raid_disk >= 0)
|
|
first = last = rdev->raid_disk;
|
|
|
|
for (mirror = first; mirror <= last; 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;
|
|
err = 0;
|
|
/* As all devices are equivalent, we don't need a full recovery
|
|
* if this was recently any drive of the array
|
|
*/
|
|
if (rdev->saved_raid_disk < 0)
|
|
conf->fullsync = 1;
|
|
rcu_assign_pointer(p->rdev, rdev);
|
|
break;
|
|
}
|
|
|
|
print_conf(conf);
|
|
return err;
|
|
}
|
|
|
|
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 (test_bit(In_sync, &rdev->flags) ||
|
|
atomic_read(&rdev->nr_pending)) {
|
|
err = -EBUSY;
|
|
goto abort;
|
|
}
|
|
/* Only remove non-faulty devices is recovery
|
|
* is not possible.
|
|
*/
|
|
if (!test_bit(Faulty, &rdev->flags) &&
|
|
mddev->degraded < conf->raid_disks) {
|
|
err = -EBUSY;
|
|
goto abort;
|
|
}
|
|
p->rdev = NULL;
|
|
synchronize_rcu();
|
|
if (atomic_read(&rdev->nr_pending)) {
|
|
/* lost the race, try later */
|
|
err = -EBUSY;
|
|
p->rdev = rdev;
|
|
}
|
|
}
|
|
abort:
|
|
|
|
print_conf(conf);
|
|
return err;
|
|
}
|
|
|
|
|
|
static void end_sync_read(struct bio *bio, int error)
|
|
{
|
|
r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
|
|
int i;
|
|
|
|
for (i=r1_bio->mddev->raid_disks; i--; )
|
|
if (r1_bio->bios[i] == bio)
|
|
break;
|
|
BUG_ON(i < 0);
|
|
update_head_pos(i, 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 (test_bit(BIO_UPTODATE, &bio->bi_flags))
|
|
set_bit(R1BIO_Uptodate, &r1_bio->state);
|
|
|
|
if (atomic_dec_and_test(&r1_bio->remaining))
|
|
reschedule_retry(r1_bio);
|
|
}
|
|
|
|
static void end_sync_write(struct bio *bio, 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;
|
|
|
|
for (i = 0; i < conf->raid_disks; i++)
|
|
if (r1_bio->bios[i] == bio) {
|
|
mirror = i;
|
|
break;
|
|
}
|
|
if (!uptodate) {
|
|
int sync_blocks = 0;
|
|
sector_t s = r1_bio->sector;
|
|
long sectors_to_go = r1_bio->sectors;
|
|
/* make sure these bits doesn't get cleared. */
|
|
do {
|
|
bitmap_end_sync(mddev->bitmap, s,
|
|
&sync_blocks, 1);
|
|
s += sync_blocks;
|
|
sectors_to_go -= sync_blocks;
|
|
} while (sectors_to_go > 0);
|
|
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);
|
|
}
|
|
}
|
|
|
|
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];
|
|
|
|
|
|
if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
|
|
/* We have read all readable devices. If we haven't
|
|
* got the block, then there is no hope left.
|
|
* If we have, then we want to do a comparison
|
|
* and skip the write if everything is the same.
|
|
* If any blocks failed to read, then we need to
|
|
* attempt an over-write
|
|
*/
|
|
int primary;
|
|
if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
|
|
for (i=0; i<mddev->raid_disks; i++)
|
|
if (r1_bio->bios[i]->bi_end_io == end_sync_read)
|
|
md_error(mddev, conf->mirrors[i].rdev);
|
|
|
|
md_done_sync(mddev, r1_bio->sectors, 1);
|
|
put_buf(r1_bio);
|
|
return;
|
|
}
|
|
for (primary=0; primary<mddev->raid_disks; primary++)
|
|
if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
|
|
test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) {
|
|
r1_bio->bios[primary]->bi_end_io = NULL;
|
|
rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
|
|
break;
|
|
}
|
|
r1_bio->read_disk = primary;
|
|
for (i=0; i<mddev->raid_disks; i++)
|
|
if (r1_bio->bios[i]->bi_end_io == end_sync_read) {
|
|
int j;
|
|
int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);
|
|
struct bio *pbio = r1_bio->bios[primary];
|
|
struct bio *sbio = r1_bio->bios[i];
|
|
|
|
if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) {
|
|
for (j = vcnt; j-- ; ) {
|
|
struct page *p, *s;
|
|
p = pbio->bi_io_vec[j].bv_page;
|
|
s = sbio->bi_io_vec[j].bv_page;
|
|
if (memcmp(page_address(p),
|
|
page_address(s),
|
|
PAGE_SIZE))
|
|
break;
|
|
}
|
|
} else
|
|
j = 0;
|
|
if (j >= 0)
|
|
mddev->resync_mismatches += r1_bio->sectors;
|
|
if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
|
|
&& test_bit(BIO_UPTODATE, &sbio->bi_flags))) {
|
|
sbio->bi_end_io = NULL;
|
|
rdev_dec_pending(conf->mirrors[i].rdev, mddev);
|
|
} else {
|
|
/* fixup the bio for reuse */
|
|
int size;
|
|
sbio->bi_vcnt = vcnt;
|
|
sbio->bi_size = r1_bio->sectors << 9;
|
|
sbio->bi_idx = 0;
|
|
sbio->bi_phys_segments = 0;
|
|
sbio->bi_flags &= ~(BIO_POOL_MASK - 1);
|
|
sbio->bi_flags |= 1 << BIO_UPTODATE;
|
|
sbio->bi_next = NULL;
|
|
sbio->bi_sector = r1_bio->sector +
|
|
conf->mirrors[i].rdev->data_offset;
|
|
sbio->bi_bdev = conf->mirrors[i].rdev->bdev;
|
|
size = sbio->bi_size;
|
|
for (j = 0; j < vcnt ; j++) {
|
|
struct bio_vec *bi;
|
|
bi = &sbio->bi_io_vec[j];
|
|
bi->bv_offset = 0;
|
|
if (size > PAGE_SIZE)
|
|
bi->bv_len = PAGE_SIZE;
|
|
else
|
|
bi->bv_len = size;
|
|
size -= PAGE_SIZE;
|
|
memcpy(page_address(bi->bv_page),
|
|
page_address(pbio->bi_io_vec[j].bv_page),
|
|
PAGE_SIZE);
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
|
|
/* ouch - failed to read all of that.
|
|
* Try some synchronous reads of other devices to get
|
|
* good data, much like with normal read errors. Only
|
|
* read into the pages we already have so we don't
|
|
* need to re-issue the read request.
|
|
* We don't need to freeze the array, because being in an
|
|
* active sync request, there is no normal IO, and
|
|
* no overlapping syncs.
|
|
*/
|
|
sector_t sect = r1_bio->sector;
|
|
int sectors = r1_bio->sectors;
|
|
int idx = 0;
|
|
|
|
while(sectors) {
|
|
int s = sectors;
|
|
int d = r1_bio->read_disk;
|
|
int success = 0;
|
|
mdk_rdev_t *rdev;
|
|
|
|
if (s > (PAGE_SIZE>>9))
|
|
s = PAGE_SIZE >> 9;
|
|
do {
|
|
if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
|
|
/* No rcu protection needed here devices
|
|
* can only be removed when no resync is
|
|
* active, and resync is currently active
|
|
*/
|
|
rdev = conf->mirrors[d].rdev;
|
|
if (sync_page_io(rdev->bdev,
|
|
sect + rdev->data_offset,
|
|
s<<9,
|
|
bio->bi_io_vec[idx].bv_page,
|
|
READ)) {
|
|
success = 1;
|
|
break;
|
|
}
|
|
}
|
|
d++;
|
|
if (d == conf->raid_disks)
|
|
d = 0;
|
|
} while (!success && d != r1_bio->read_disk);
|
|
|
|
if (success) {
|
|
int start = d;
|
|
/* write it back and re-read */
|
|
set_bit(R1BIO_Uptodate, &r1_bio->state);
|
|
while (d != r1_bio->read_disk) {
|
|
if (d == 0)
|
|
d = conf->raid_disks;
|
|
d--;
|
|
if (r1_bio->bios[d]->bi_end_io != end_sync_read)
|
|
continue;
|
|
rdev = conf->mirrors[d].rdev;
|
|
atomic_add(s, &rdev->corrected_errors);
|
|
if (sync_page_io(rdev->bdev,
|
|
sect + rdev->data_offset,
|
|
s<<9,
|
|
bio->bi_io_vec[idx].bv_page,
|
|
WRITE) == 0)
|
|
md_error(mddev, rdev);
|
|
}
|
|
d = start;
|
|
while (d != r1_bio->read_disk) {
|
|
if (d == 0)
|
|
d = conf->raid_disks;
|
|
d--;
|
|
if (r1_bio->bios[d]->bi_end_io != end_sync_read)
|
|
continue;
|
|
rdev = conf->mirrors[d].rdev;
|
|
if (sync_page_io(rdev->bdev,
|
|
sect + rdev->data_offset,
|
|
s<<9,
|
|
bio->bi_io_vec[idx].bv_page,
|
|
READ) == 0)
|
|
md_error(mddev, rdev);
|
|
}
|
|
} else {
|
|
char b[BDEVNAME_SIZE];
|
|
/* Cannot read from anywhere, array is toast */
|
|
md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);
|
|
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;
|
|
}
|
|
sectors -= s;
|
|
sect += s;
|
|
idx ++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* schedule writes
|
|
*/
|
|
atomic_set(&r1_bio->remaining, 1);
|
|
for (i = 0; i < disks ; i++) {
|
|
wbio = r1_bio->bios[i];
|
|
if (wbio->bi_end_io == NULL ||
|
|
(wbio->bi_end_io == end_sync_read &&
|
|
(i == r1_bio->read_disk ||
|
|
!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
|
|
continue;
|
|
|
|
wbio->bi_rw = WRITE;
|
|
wbio->bi_end_io = end_sync_write;
|
|
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)) {
|
|
/* if we're here, all write(s) have completed, so clean up */
|
|
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 fix_read_error(conf_t *conf, int read_disk,
|
|
sector_t sect, int sectors)
|
|
{
|
|
mddev_t *mddev = conf->mddev;
|
|
while(sectors) {
|
|
int s = sectors;
|
|
int d = read_disk;
|
|
int success = 0;
|
|
int start;
|
|
mdk_rdev_t *rdev;
|
|
|
|
if (s > (PAGE_SIZE>>9))
|
|
s = PAGE_SIZE >> 9;
|
|
|
|
do {
|
|
/* Note: no rcu protection needed here
|
|
* as this is synchronous in the raid1d thread
|
|
* which is the thread that might remove
|
|
* a device. If raid1d ever becomes multi-threaded....
|
|
*/
|
|
rdev = conf->mirrors[d].rdev;
|
|
if (rdev &&
|
|
test_bit(In_sync, &rdev->flags) &&
|
|
sync_page_io(rdev->bdev,
|
|
sect + rdev->data_offset,
|
|
s<<9,
|
|
conf->tmppage, READ))
|
|
success = 1;
|
|
else {
|
|
d++;
|
|
if (d == conf->raid_disks)
|
|
d = 0;
|
|
}
|
|
} while (!success && d != read_disk);
|
|
|
|
if (!success) {
|
|
/* Cannot read from anywhere -- bye bye array */
|
|
md_error(mddev, conf->mirrors[read_disk].rdev);
|
|
break;
|
|
}
|
|
/* write it back and re-read */
|
|
start = d;
|
|
while (d != read_disk) {
|
|
if (d==0)
|
|
d = conf->raid_disks;
|
|
d--;
|
|
rdev = conf->mirrors[d].rdev;
|
|
if (rdev &&
|
|
test_bit(In_sync, &rdev->flags)) {
|
|
if (sync_page_io(rdev->bdev,
|
|
sect + rdev->data_offset,
|
|
s<<9, conf->tmppage, WRITE)
|
|
== 0)
|
|
/* Well, this device is dead */
|
|
md_error(mddev, rdev);
|
|
}
|
|
}
|
|
d = start;
|
|
while (d != read_disk) {
|
|
char b[BDEVNAME_SIZE];
|
|
if (d==0)
|
|
d = conf->raid_disks;
|
|
d--;
|
|
rdev = conf->mirrors[d].rdev;
|
|
if (rdev &&
|
|
test_bit(In_sync, &rdev->flags)) {
|
|
if (sync_page_io(rdev->bdev,
|
|
sect + rdev->data_offset,
|
|
s<<9, conf->tmppage, READ)
|
|
== 0)
|
|
/* Well, this device is dead */
|
|
md_error(mddev, rdev);
|
|
else {
|
|
atomic_add(s, &rdev->corrected_errors);
|
|
printk(KERN_INFO
|
|
"raid1:%s: read error corrected "
|
|
"(%d sectors at %llu on %s)\n",
|
|
mdname(mddev), s,
|
|
(unsigned long long)(sect +
|
|
rdev->data_offset),
|
|
bdevname(rdev->bdev, b));
|
|
}
|
|
}
|
|
}
|
|
sectors -= s;
|
|
sect += s;
|
|
}
|
|
}
|
|
|
|
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);
|
|
|
|
for (;;) {
|
|
char b[BDEVNAME_SIZE];
|
|
|
|
unplug += flush_pending_writes(conf);
|
|
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
if (list_empty(head)) {
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
break;
|
|
}
|
|
r1_bio = list_entry(head->prev, r1bio_t, retry_list);
|
|
list_del(head->prev);
|
|
conf->nr_queued--;
|
|
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 if (test_bit(R1BIO_BarrierRetry, &r1_bio->state)) {
|
|
/* some requests in the r1bio were BIO_RW_BARRIER
|
|
* requests which failed with -EOPNOTSUPP. Hohumm..
|
|
* Better resubmit without the barrier.
|
|
* We know which devices to resubmit for, because
|
|
* all others have had their bios[] entry cleared.
|
|
* We already have a nr_pending reference on these rdevs.
|
|
*/
|
|
int i;
|
|
const int do_sync = bio_sync(r1_bio->master_bio);
|
|
clear_bit(R1BIO_BarrierRetry, &r1_bio->state);
|
|
clear_bit(R1BIO_Barrier, &r1_bio->state);
|
|
for (i=0; i < conf->raid_disks; i++)
|
|
if (r1_bio->bios[i])
|
|
atomic_inc(&r1_bio->remaining);
|
|
for (i=0; i < conf->raid_disks; i++)
|
|
if (r1_bio->bios[i]) {
|
|
struct bio_vec *bvec;
|
|
int j;
|
|
|
|
bio = bio_clone(r1_bio->master_bio, GFP_NOIO);
|
|
/* copy pages from the failed bio, as
|
|
* this might be a write-behind device */
|
|
__bio_for_each_segment(bvec, bio, j, 0)
|
|
bvec->bv_page = bio_iovec_idx(r1_bio->bios[i], j)->bv_page;
|
|
bio_put(r1_bio->bios[i]);
|
|
bio->bi_sector = r1_bio->sector +
|
|
conf->mirrors[i].rdev->data_offset;
|
|
bio->bi_bdev = conf->mirrors[i].rdev->bdev;
|
|
bio->bi_end_io = raid1_end_write_request;
|
|
bio->bi_rw = WRITE | do_sync;
|
|
bio->bi_private = r1_bio;
|
|
r1_bio->bios[i] = bio;
|
|
generic_make_request(bio);
|
|
}
|
|
} else {
|
|
int disk;
|
|
|
|
/* we got a read error. Maybe the drive is bad. Maybe just
|
|
* the block and we can fix it.
|
|
* We freeze all other IO, and try reading the block from
|
|
* other devices. When we find one, we re-write
|
|
* and check it that fixes the read error.
|
|
* This is all done synchronously while the array is
|
|
* frozen
|
|
*/
|
|
if (mddev->ro == 0) {
|
|
freeze_array(conf);
|
|
fix_read_error(conf, r1_bio->read_disk,
|
|
r1_bio->sector,
|
|
r1_bio->sectors);
|
|
unfreeze_array(conf);
|
|
}
|
|
|
|
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 {
|
|
const int do_sync = bio_sync(r1_bio->master_bio);
|
|
r1_bio->bios[r1_bio->read_disk] =
|
|
mddev->ro ? IO_BLOCKED : 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 | do_sync;
|
|
bio->bi_private = r1_bio;
|
|
unplug = 1;
|
|
generic_make_request(bio);
|
|
}
|
|
}
|
|
}
|
|
if (unplug)
|
|
unplug_slaves(mddev);
|
|
}
|
|
|
|
|
|
static int init_resync(conf_t *conf)
|
|
{
|
|
int buffs;
|
|
|
|
buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
|
|
BUG_ON(conf->r1buf_pool);
|
|
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 sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
r1bio_t *r1_bio;
|
|
struct bio *bio;
|
|
sector_t max_sector, nr_sectors;
|
|
int disk = -1;
|
|
int i;
|
|
int wonly = -1;
|
|
int write_targets = 0, read_targets = 0;
|
|
int sync_blocks;
|
|
int still_degraded = 0;
|
|
|
|
if (!conf->r1buf_pool)
|
|
{
|
|
/*
|
|
printk("sync start - bitmap %p\n", mddev->bitmap);
|
|
*/
|
|
if (init_resync(conf))
|
|
return 0;
|
|
}
|
|
|
|
max_sector = mddev->size << 1;
|
|
if (sector_nr >= max_sector) {
|
|
/* If we aborted, we need to abort the
|
|
* sync on the 'current' bitmap chunk (there will
|
|
* only be one in raid1 resync.
|
|
* We can find the current addess in mddev->curr_resync
|
|
*/
|
|
if (mddev->curr_resync < max_sector) /* aborted */
|
|
bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
|
|
&sync_blocks, 1);
|
|
else /* completed sync */
|
|
conf->fullsync = 0;
|
|
|
|
bitmap_close_sync(mddev->bitmap);
|
|
close_sync(conf);
|
|
return 0;
|
|
}
|
|
|
|
if (mddev->bitmap == NULL &&
|
|
mddev->recovery_cp == MaxSector &&
|
|
!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
|
|
conf->fullsync == 0) {
|
|
*skipped = 1;
|
|
return max_sector - sector_nr;
|
|
}
|
|
/* before building a request, check if we can skip these blocks..
|
|
* This call the bitmap_start_sync doesn't actually record anything
|
|
*/
|
|
if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
|
|
!conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
|
|
/* We can skip this block, and probably several more */
|
|
*skipped = 1;
|
|
return sync_blocks;
|
|
}
|
|
/*
|
|
* If there is non-resync activity waiting for a turn,
|
|
* and resync is going fast enough,
|
|
* then let it though before starting on this new sync request.
|
|
*/
|
|
if (!go_faster && conf->nr_waiting)
|
|
msleep_interruptible(1000);
|
|
|
|
bitmap_cond_end_sync(mddev->bitmap, sector_nr);
|
|
raise_barrier(conf);
|
|
|
|
conf->next_resync = sector_nr;
|
|
|
|
r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO);
|
|
rcu_read_lock();
|
|
/*
|
|
* If we get a correctably read error during resync or recovery,
|
|
* we might want to read from a different device. So we
|
|
* flag all drives that could conceivably be read from for READ,
|
|
* and any others (which will be non-In_sync devices) for WRITE.
|
|
* If a read fails, we try reading from something else for which READ
|
|
* is OK.
|
|
*/
|
|
|
|
r1_bio->mddev = mddev;
|
|
r1_bio->sector = sector_nr;
|
|
r1_bio->state = 0;
|
|
set_bit(R1BIO_IsSync, &r1_bio->state);
|
|
|
|
for (i=0; i < conf->raid_disks; i++) {
|
|
mdk_rdev_t *rdev;
|
|
bio = r1_bio->bios[i];
|
|
|
|
/* take from bio_init */
|
|
bio->bi_next = NULL;
|
|
bio->bi_flags |= 1 << BIO_UPTODATE;
|
|
bio->bi_rw = READ;
|
|
bio->bi_vcnt = 0;
|
|
bio->bi_idx = 0;
|
|
bio->bi_phys_segments = 0;
|
|
bio->bi_size = 0;
|
|
bio->bi_end_io = NULL;
|
|
bio->bi_private = NULL;
|
|
|
|
rdev = rcu_dereference(conf->mirrors[i].rdev);
|
|
if (rdev == NULL ||
|
|
test_bit(Faulty, &rdev->flags)) {
|
|
still_degraded = 1;
|
|
continue;
|
|
} else if (!test_bit(In_sync, &rdev->flags)) {
|
|
bio->bi_rw = WRITE;
|
|
bio->bi_end_io = end_sync_write;
|
|
write_targets ++;
|
|
} else {
|
|
/* may need to read from here */
|
|
bio->bi_rw = READ;
|
|
bio->bi_end_io = end_sync_read;
|
|
if (test_bit(WriteMostly, &rdev->flags)) {
|
|
if (wonly < 0)
|
|
wonly = i;
|
|
} else {
|
|
if (disk < 0)
|
|
disk = i;
|
|
}
|
|
read_targets++;
|
|
}
|
|
atomic_inc(&rdev->nr_pending);
|
|
bio->bi_sector = sector_nr + rdev->data_offset;
|
|
bio->bi_bdev = rdev->bdev;
|
|
bio->bi_private = r1_bio;
|
|
}
|
|
rcu_read_unlock();
|
|
if (disk < 0)
|
|
disk = wonly;
|
|
r1_bio->read_disk = disk;
|
|
|
|
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
|
|
/* extra read targets are also write targets */
|
|
write_targets += read_targets-1;
|
|
|
|
if (write_targets == 0 || read_targets == 0) {
|
|
/* There is nowhere to write, so all non-sync
|
|
* drives must be failed - so we are finished
|
|
*/
|
|
sector_t rv = max_sector - sector_nr;
|
|
*skipped = 1;
|
|
put_buf(r1_bio);
|
|
return rv;
|
|
}
|
|
|
|
if (max_sector > mddev->resync_max)
|
|
max_sector = mddev->resync_max; /* Don't do IO beyond here */
|
|
nr_sectors = 0;
|
|
sync_blocks = 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;
|
|
if (sync_blocks == 0) {
|
|
if (!bitmap_start_sync(mddev->bitmap, sector_nr,
|
|
&sync_blocks, still_degraded) &&
|
|
!conf->fullsync &&
|
|
!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
|
|
break;
|
|
BUG_ON(sync_blocks < (PAGE_SIZE>>9));
|
|
if (len > (sync_blocks<<9))
|
|
len = sync_blocks<<9;
|
|
}
|
|
|
|
for (i=0 ; i < conf->raid_disks; i++) {
|
|
bio = r1_bio->bios[i];
|
|
if (bio->bi_end_io) {
|
|
page = bio->bi_io_vec[bio->bi_vcnt].bv_page;
|
|
if (bio_add_page(bio, page, len, 0) == 0) {
|
|
/* stop here */
|
|
bio->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;
|
|
sync_blocks -= (len>>9);
|
|
} while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES);
|
|
bio_full:
|
|
r1_bio->sectors = nr_sectors;
|
|
|
|
/* For a user-requested sync, we read all readable devices and do a
|
|
* compare
|
|
*/
|
|
if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
|
|
atomic_set(&r1_bio->remaining, read_targets);
|
|
for (i=0; i<conf->raid_disks; i++) {
|
|
bio = r1_bio->bios[i];
|
|
if (bio->bi_end_io == end_sync_read) {
|
|
md_sync_acct(bio->bi_bdev, nr_sectors);
|
|
generic_make_request(bio);
|
|
}
|
|
}
|
|
} else {
|
|
atomic_set(&r1_bio->remaining, 1);
|
|
bio = r1_bio->bios[r1_bio->read_disk];
|
|
md_sync_acct(bio->bi_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;
|
|
}
|
|
if (mddev->reshape_position != MaxSector) {
|
|
printk("raid1: %s: reshape_position set but not supported\n",
|
|
mdname(mddev));
|
|
goto out;
|
|
}
|
|
/*
|
|
* copy the already verified devices into our private RAID1
|
|
* bookkeeping area. [whatever we allocate in run(),
|
|
* should be freed in stop()]
|
|
*/
|
|
conf = kzalloc(sizeof(conf_t), GFP_KERNEL);
|
|
mddev->private = conf;
|
|
if (!conf)
|
|
goto out_no_mem;
|
|
|
|
conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks,
|
|
GFP_KERNEL);
|
|
if (!conf->mirrors)
|
|
goto out_no_mem;
|
|
|
|
conf->tmppage = alloc_page(GFP_KERNEL);
|
|
if (!conf->tmppage)
|
|
goto out_no_mem;
|
|
|
|
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;
|
|
|
|
spin_lock_init(&conf->device_lock);
|
|
mddev->queue->queue_lock = &conf->device_lock;
|
|
|
|
rdev_for_each(rdev, tmp, mddev) {
|
|
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;
|
|
}
|
|
conf->raid_disks = mddev->raid_disks;
|
|
conf->mddev = mddev;
|
|
INIT_LIST_HEAD(&conf->retry_list);
|
|
|
|
spin_lock_init(&conf->resync_lock);
|
|
init_waitqueue_head(&conf->wait_barrier);
|
|
|
|
bio_list_init(&conf->pending_bio_list);
|
|
bio_list_init(&conf->flushing_bio_list);
|
|
|
|
|
|
mddev->degraded = 0;
|
|
for (i = 0; i < conf->raid_disks; i++) {
|
|
|
|
disk = conf->mirrors + i;
|
|
|
|
if (!disk->rdev ||
|
|
!test_bit(In_sync, &disk->rdev->flags)) {
|
|
disk->head_position = 0;
|
|
mddev->degraded++;
|
|
if (disk->rdev)
|
|
conf->fullsync = 1;
|
|
}
|
|
}
|
|
if (mddev->degraded == conf->raid_disks) {
|
|
printk(KERN_ERR "raid1: no operational mirrors for %s\n",
|
|
mdname(mddev));
|
|
goto out_free_conf;
|
|
}
|
|
if (conf->raid_disks - mddev->degraded == 1)
|
|
mddev->recovery_cp = MaxSector;
|
|
|
|
/*
|
|
* 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 ||
|
|
!test_bit(In_sync, &conf->mirrors[j].rdev->flags)) ; 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_sectors = mddev->size * 2;
|
|
|
|
mddev->queue->unplug_fn = raid1_unplug;
|
|
mddev->queue->backing_dev_info.congested_fn = raid1_congested;
|
|
mddev->queue->backing_dev_info.congested_data = mddev;
|
|
|
|
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);
|
|
kfree(conf->mirrors);
|
|
safe_put_page(conf->tmppage);
|
|
kfree(conf->poolinfo);
|
|
kfree(conf);
|
|
mddev->private = NULL;
|
|
}
|
|
out:
|
|
return -EIO;
|
|
}
|
|
|
|
static int stop(mddev_t *mddev)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
struct bitmap *bitmap = mddev->bitmap;
|
|
int behind_wait = 0;
|
|
|
|
/* wait for behind writes to complete */
|
|
while (bitmap && atomic_read(&bitmap->behind_writes) > 0) {
|
|
behind_wait++;
|
|
printk(KERN_INFO "raid1: behind writes in progress on device %s, waiting to stop (%d)\n", mdname(mddev), behind_wait);
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
schedule_timeout(HZ); /* wait a second */
|
|
/* need to kick something here to make sure I/O goes? */
|
|
}
|
|
|
|
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);
|
|
kfree(conf->mirrors);
|
|
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_sectors = sectors;
|
|
set_capacity(mddev->gendisk, mddev->array_sectors);
|
|
mddev->changed = 1;
|
|
if (mddev->array_sectors / 2 > mddev->size &&
|
|
mddev->recovery_cp == MaxSector) {
|
|
mddev->recovery_cp = mddev->size << 1;
|
|
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
|
|
}
|
|
mddev->size = mddev->array_sectors / 2;
|
|
mddev->resync_max_sectors = sectors;
|
|
return 0;
|
|
}
|
|
|
|
static int raid1_reshape(mddev_t *mddev)
|
|
{
|
|
/* 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.
|
|
*
|
|
* At the same time, we "pack" the devices so that all the missing
|
|
* devices have the higher raid_disk numbers.
|
|
*/
|
|
mempool_t *newpool, *oldpool;
|
|
struct pool_info *newpoolinfo;
|
|
mirror_info_t *newmirrors;
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
int cnt, raid_disks;
|
|
unsigned long flags;
|
|
int d, d2, err;
|
|
|
|
/* Cannot change chunk_size, layout, or level */
|
|
if (mddev->chunk_size != mddev->new_chunk ||
|
|
mddev->layout != mddev->new_layout ||
|
|
mddev->level != mddev->new_level) {
|
|
mddev->new_chunk = mddev->chunk_size;
|
|
mddev->new_layout = mddev->layout;
|
|
mddev->new_level = mddev->level;
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = md_allow_write(mddev);
|
|
if (err)
|
|
return err;
|
|
|
|
raid_disks = mddev->raid_disks + mddev->delta_disks;
|
|
|
|
if (raid_disks < conf->raid_disks) {
|
|
cnt=0;
|
|
for (d= 0; d < conf->raid_disks; d++)
|
|
if (conf->mirrors[d].rdev)
|
|
cnt++;
|
|
if (cnt > raid_disks)
|
|
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 = kzalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL);
|
|
if (!newmirrors) {
|
|
kfree(newpoolinfo);
|
|
mempool_destroy(newpool);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
raise_barrier(conf);
|
|
|
|
/* ok, everything is stopped */
|
|
oldpool = conf->r1bio_pool;
|
|
conf->r1bio_pool = newpool;
|
|
|
|
for (d = d2 = 0; d < conf->raid_disks; d++) {
|
|
mdk_rdev_t *rdev = conf->mirrors[d].rdev;
|
|
if (rdev && rdev->raid_disk != d2) {
|
|
char nm[20];
|
|
sprintf(nm, "rd%d", rdev->raid_disk);
|
|
sysfs_remove_link(&mddev->kobj, nm);
|
|
rdev->raid_disk = d2;
|
|
sprintf(nm, "rd%d", rdev->raid_disk);
|
|
sysfs_remove_link(&mddev->kobj, nm);
|
|
if (sysfs_create_link(&mddev->kobj,
|
|
&rdev->kobj, nm))
|
|
printk(KERN_WARNING
|
|
"md/raid1: cannot register "
|
|
"%s for %s\n",
|
|
nm, mdname(mddev));
|
|
}
|
|
if (rdev)
|
|
newmirrors[d2++].rdev = rdev;
|
|
}
|
|
kfree(conf->mirrors);
|
|
conf->mirrors = newmirrors;
|
|
kfree(conf->poolinfo);
|
|
conf->poolinfo = newpoolinfo;
|
|
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
mddev->degraded += (raid_disks - conf->raid_disks);
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
conf->raid_disks = mddev->raid_disks = raid_disks;
|
|
mddev->delta_disks = 0;
|
|
|
|
conf->last_used = 0; /* just make sure it is in-range */
|
|
lower_barrier(conf);
|
|
|
|
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
|
|
md_wakeup_thread(mddev->thread);
|
|
|
|
mempool_destroy(oldpool);
|
|
return 0;
|
|
}
|
|
|
|
static void raid1_quiesce(mddev_t *mddev, int state)
|
|
{
|
|
conf_t *conf = mddev_to_conf(mddev);
|
|
|
|
switch(state) {
|
|
case 1:
|
|
raise_barrier(conf);
|
|
break;
|
|
case 0:
|
|
lower_barrier(conf);
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
static struct mdk_personality raid1_personality =
|
|
{
|
|
.name = "raid1",
|
|
.level = 1,
|
|
.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,
|
|
.check_reshape = raid1_reshape,
|
|
.quiesce = raid1_quiesce,
|
|
};
|
|
|
|
static int __init raid_init(void)
|
|
{
|
|
return register_md_personality(&raid1_personality);
|
|
}
|
|
|
|
static void raid_exit(void)
|
|
{
|
|
unregister_md_personality(&raid1_personality);
|
|
}
|
|
|
|
module_init(raid_init);
|
|
module_exit(raid_exit);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("md-personality-3"); /* RAID1 */
|
|
MODULE_ALIAS("md-raid1");
|
|
MODULE_ALIAS("md-level-1");
|