| /* |
| * raid1.c : Multiple Devices driver for Linux |
| * |
| * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat |
| * |
| * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman |
| * |
| * RAID-1 management functions. |
| * |
| * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000 |
| * |
| * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk> |
| * Various fixes by Neil Brown <neilb@cse.unsw.edu.au> |
| * |
| * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support |
| * bitmapped intelligence in resync: |
| * |
| * - bitmap marked during normal i/o |
| * - bitmap used to skip nondirty blocks during sync |
| * |
| * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology: |
| * - persistent bitmap code |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2, or (at your option) |
| * any later version. |
| * |
| * You should have received a copy of the GNU General Public License |
| * (for example /usr/src/linux/COPYING); if not, write to the Free |
| * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| #include <linux/slab.h> |
| #include <linux/delay.h> |
| #include <linux/blkdev.h> |
| #include <linux/module.h> |
| #include <linux/seq_file.h> |
| #include <linux/ratelimit.h> |
| #include "md.h" |
| #include "raid1.h" |
| #include "bitmap.h" |
| |
| /* |
| * Number of guaranteed r1bios in case of extreme VM load: |
| */ |
| #define NR_RAID1_BIOS 256 |
| |
| /* when we get a read error on a read-only array, we redirect to another |
| * device without failing the first device, or trying to over-write to |
| * correct the read error. To keep track of bad blocks on a per-bio |
| * level, we store IO_BLOCKED in the appropriate 'bios' pointer |
| */ |
| #define IO_BLOCKED ((struct bio *)1) |
| /* When we successfully write to a known bad-block, we need to remove the |
| * bad-block marking which must be done from process context. So we record |
| * the success by setting devs[n].bio to IO_MADE_GOOD |
| */ |
| #define IO_MADE_GOOD ((struct bio *)2) |
| |
| #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2) |
| |
| /* When there are this many requests queue to be written by |
| * the raid1 thread, we become 'congested' to provide back-pressure |
| * for writeback. |
| */ |
| static int max_queued_requests = 1024; |
| |
| static void allow_barrier(struct r1conf *conf, sector_t start_next_window, |
| sector_t bi_sector); |
| static void lower_barrier(struct r1conf *conf); |
| |
| static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data) |
| { |
| struct pool_info *pi = data; |
| int size = offsetof(struct r1bio, bios[pi->raid_disks]); |
| |
| /* allocate a r1bio with room for raid_disks entries in the bios array */ |
| return kzalloc(size, gfp_flags); |
| } |
| |
| static void r1bio_pool_free(void *r1_bio, void *data) |
| { |
| kfree(r1_bio); |
| } |
| |
| #define RESYNC_BLOCK_SIZE (64*1024) |
| #define RESYNC_DEPTH 32 |
| #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9) |
| #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) |
| #define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH) |
| #define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9) |
| #define CLUSTER_RESYNC_WINDOW (16 * RESYNC_WINDOW) |
| #define CLUSTER_RESYNC_WINDOW_SECTORS (CLUSTER_RESYNC_WINDOW >> 9) |
| #define NEXT_NORMALIO_DISTANCE (3 * RESYNC_WINDOW_SECTORS) |
| |
| static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) |
| { |
| struct pool_info *pi = data; |
| struct r1bio *r1_bio; |
| struct bio *bio; |
| int need_pages; |
| int i, j; |
| |
| r1_bio = r1bio_pool_alloc(gfp_flags, pi); |
| if (!r1_bio) |
| return NULL; |
| |
| /* |
| * Allocate bios : 1 for reading, n-1 for writing |
| */ |
| for (j = pi->raid_disks ; j-- ; ) { |
| bio = bio_kmalloc(gfp_flags, RESYNC_PAGES); |
| if (!bio) |
| goto out_free_bio; |
| r1_bio->bios[j] = bio; |
| } |
| /* |
| * Allocate RESYNC_PAGES data pages and attach them to |
| * the first bio. |
| * If this is a user-requested check/repair, allocate |
| * RESYNC_PAGES for each bio. |
| */ |
| if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) |
| need_pages = pi->raid_disks; |
| else |
| need_pages = 1; |
| for (j = 0; j < need_pages; j++) { |
| bio = r1_bio->bios[j]; |
| bio->bi_vcnt = RESYNC_PAGES; |
| |
| if (bio_alloc_pages(bio, gfp_flags)) |
| goto out_free_pages; |
| } |
| /* If not user-requests, copy the page pointers to all bios */ |
| if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) { |
| for (i=0; i<RESYNC_PAGES ; i++) |
| for (j=1; j<pi->raid_disks; j++) |
| r1_bio->bios[j]->bi_io_vec[i].bv_page = |
| r1_bio->bios[0]->bi_io_vec[i].bv_page; |
| } |
| |
| r1_bio->master_bio = NULL; |
| |
| return r1_bio; |
| |
| out_free_pages: |
| while (--j >= 0) { |
| struct bio_vec *bv; |
| |
| bio_for_each_segment_all(bv, r1_bio->bios[j], i) |
| __free_page(bv->bv_page); |
| } |
| |
| out_free_bio: |
| while (++j < pi->raid_disks) |
| bio_put(r1_bio->bios[j]); |
| r1bio_pool_free(r1_bio, data); |
| return NULL; |
| } |
| |
| static void r1buf_pool_free(void *__r1_bio, void *data) |
| { |
| struct pool_info *pi = data; |
| int i,j; |
| struct r1bio *r1bio = __r1_bio; |
| |
| for (i = 0; i < RESYNC_PAGES; i++) |
| for (j = pi->raid_disks; j-- ;) { |
| if (j == 0 || |
| r1bio->bios[j]->bi_io_vec[i].bv_page != |
| r1bio->bios[0]->bi_io_vec[i].bv_page) |
| safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page); |
| } |
| for (i=0 ; i < pi->raid_disks; i++) |
| bio_put(r1bio->bios[i]); |
| |
| r1bio_pool_free(r1bio, data); |
| } |
| |
| static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio) |
| { |
| int i; |
| |
| for (i = 0; i < conf->raid_disks * 2; i++) { |
| struct bio **bio = r1_bio->bios + i; |
| if (!BIO_SPECIAL(*bio)) |
| bio_put(*bio); |
| *bio = NULL; |
| } |
| } |
| |
| static void free_r1bio(struct r1bio *r1_bio) |
| { |
| struct r1conf *conf = r1_bio->mddev->private; |
| |
| put_all_bios(conf, r1_bio); |
| mempool_free(r1_bio, conf->r1bio_pool); |
| } |
| |
| static void put_buf(struct r1bio *r1_bio) |
| { |
| struct r1conf *conf = r1_bio->mddev->private; |
| int i; |
| |
| for (i = 0; i < conf->raid_disks * 2; i++) { |
| struct bio *bio = r1_bio->bios[i]; |
| if (bio->bi_end_io) |
| rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev); |
| } |
| |
| mempool_free(r1_bio, conf->r1buf_pool); |
| |
| lower_barrier(conf); |
| } |
| |
| static void reschedule_retry(struct r1bio *r1_bio) |
| { |
| unsigned long flags; |
| struct mddev *mddev = r1_bio->mddev; |
| struct r1conf *conf = mddev->private; |
| |
| spin_lock_irqsave(&conf->device_lock, flags); |
| list_add(&r1_bio->retry_list, &conf->retry_list); |
| conf->nr_queued ++; |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| |
| wake_up(&conf->wait_barrier); |
| md_wakeup_thread(mddev->thread); |
| } |
| |
| /* |
| * raid_end_bio_io() is called when we have finished servicing a mirrored |
| * operation and are ready to return a success/failure code to the buffer |
| * cache layer. |
| */ |
| static void call_bio_endio(struct r1bio *r1_bio) |
| { |
| struct bio *bio = r1_bio->master_bio; |
| int done; |
| struct r1conf *conf = r1_bio->mddev->private; |
| sector_t start_next_window = r1_bio->start_next_window; |
| sector_t bi_sector = bio->bi_iter.bi_sector; |
| |
| if (bio->bi_phys_segments) { |
| unsigned long flags; |
| spin_lock_irqsave(&conf->device_lock, flags); |
| bio->bi_phys_segments--; |
| done = (bio->bi_phys_segments == 0); |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| /* |
| * make_request() might be waiting for |
| * bi_phys_segments to decrease |
| */ |
| wake_up(&conf->wait_barrier); |
| } else |
| done = 1; |
| |
| if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) |
| bio->bi_error = -EIO; |
| |
| if (done) { |
| bio_endio(bio); |
| /* |
| * Wake up any possible resync thread that waits for the device |
| * to go idle. |
| */ |
| allow_barrier(conf, start_next_window, bi_sector); |
| } |
| } |
| |
| static void raid_end_bio_io(struct r1bio *r1_bio) |
| { |
| struct bio *bio = r1_bio->master_bio; |
| |
| /* if nobody has done the final endio yet, do it now */ |
| if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { |
| pr_debug("raid1: sync end %s on sectors %llu-%llu\n", |
| (bio_data_dir(bio) == WRITE) ? "write" : "read", |
| (unsigned long long) bio->bi_iter.bi_sector, |
| (unsigned long long) bio_end_sector(bio) - 1); |
| |
| call_bio_endio(r1_bio); |
| } |
| free_r1bio(r1_bio); |
| } |
| |
| /* |
| * Update disk head position estimator based on IRQ completion info. |
| */ |
| static inline void update_head_pos(int disk, struct r1bio *r1_bio) |
| { |
| struct r1conf *conf = r1_bio->mddev->private; |
| |
| conf->mirrors[disk].head_position = |
| r1_bio->sector + (r1_bio->sectors); |
| } |
| |
| /* |
| * Find the disk number which triggered given bio |
| */ |
| static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio) |
| { |
| int mirror; |
| struct r1conf *conf = r1_bio->mddev->private; |
| int raid_disks = conf->raid_disks; |
| |
| for (mirror = 0; mirror < raid_disks * 2; mirror++) |
| if (r1_bio->bios[mirror] == bio) |
| break; |
| |
| BUG_ON(mirror == raid_disks * 2); |
| update_head_pos(mirror, r1_bio); |
| |
| return mirror; |
| } |
| |
| static void raid1_end_read_request(struct bio *bio) |
| { |
| int uptodate = !bio->bi_error; |
| struct r1bio *r1_bio = bio->bi_private; |
| int mirror; |
| struct r1conf *conf = r1_bio->mddev->private; |
| |
| mirror = r1_bio->read_disk; |
| /* |
| * this branch is our 'one mirror IO has finished' event handler: |
| */ |
| update_head_pos(mirror, r1_bio); |
| |
| if (uptodate) |
| set_bit(R1BIO_Uptodate, &r1_bio->state); |
| else { |
| /* If all other devices have failed, we want to return |
| * the error upwards rather than fail the last device. |
| * Here we redefine "uptodate" to mean "Don't want to retry" |
| */ |
| unsigned long flags; |
| spin_lock_irqsave(&conf->device_lock, flags); |
| if (r1_bio->mddev->degraded == conf->raid_disks || |
| (r1_bio->mddev->degraded == conf->raid_disks-1 && |
| test_bit(In_sync, &conf->mirrors[mirror].rdev->flags))) |
| uptodate = 1; |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| } |
| |
| if (uptodate) { |
| raid_end_bio_io(r1_bio); |
| rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); |
| } else { |
| /* |
| * oops, read error: |
| */ |
| char b[BDEVNAME_SIZE]; |
| printk_ratelimited( |
| KERN_ERR "md/raid1:%s: %s: " |
| "rescheduling sector %llu\n", |
| mdname(conf->mddev), |
| bdevname(conf->mirrors[mirror].rdev->bdev, |
| b), |
| (unsigned long long)r1_bio->sector); |
| set_bit(R1BIO_ReadError, &r1_bio->state); |
| reschedule_retry(r1_bio); |
| /* don't drop the reference on read_disk yet */ |
| } |
| } |
| |
| static void close_write(struct r1bio *r1_bio) |
| { |
| /* it really is the end of this request */ |
| if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { |
| /* free extra copy of the data pages */ |
| int i = r1_bio->behind_page_count; |
| while (i--) |
| safe_put_page(r1_bio->behind_bvecs[i].bv_page); |
| kfree(r1_bio->behind_bvecs); |
| r1_bio->behind_bvecs = NULL; |
| } |
| /* clear the bitmap if all writes complete successfully */ |
| bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector, |
| r1_bio->sectors, |
| !test_bit(R1BIO_Degraded, &r1_bio->state), |
| test_bit(R1BIO_BehindIO, &r1_bio->state)); |
| md_write_end(r1_bio->mddev); |
| } |
| |
| static void r1_bio_write_done(struct r1bio *r1_bio) |
| { |
| if (!atomic_dec_and_test(&r1_bio->remaining)) |
| return; |
| |
| if (test_bit(R1BIO_WriteError, &r1_bio->state)) |
| reschedule_retry(r1_bio); |
| else { |
| close_write(r1_bio); |
| if (test_bit(R1BIO_MadeGood, &r1_bio->state)) |
| reschedule_retry(r1_bio); |
| else |
| raid_end_bio_io(r1_bio); |
| } |
| } |
| |
| static void raid1_end_write_request(struct bio *bio) |
| { |
| struct r1bio *r1_bio = bio->bi_private; |
| int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state); |
| struct r1conf *conf = r1_bio->mddev->private; |
| struct bio *to_put = NULL; |
| |
| mirror = find_bio_disk(r1_bio, bio); |
| |
| /* |
| * 'one mirror IO has finished' event handler: |
| */ |
| if (bio->bi_error) { |
| set_bit(WriteErrorSeen, |
| &conf->mirrors[mirror].rdev->flags); |
| if (!test_and_set_bit(WantReplacement, |
| &conf->mirrors[mirror].rdev->flags)) |
| set_bit(MD_RECOVERY_NEEDED, & |
| conf->mddev->recovery); |
| |
| set_bit(R1BIO_WriteError, &r1_bio->state); |
| } else { |
| /* |
| * Set R1BIO_Uptodate in our master bio, so that we |
| * will return a good error code for to the higher |
| * levels even if IO on some other mirrored buffer |
| * fails. |
| * |
| * The 'master' represents the composite IO operation |
| * to user-side. So if something waits for IO, then it |
| * will wait for the 'master' bio. |
| */ |
| sector_t first_bad; |
| int bad_sectors; |
| |
| r1_bio->bios[mirror] = NULL; |
| to_put = bio; |
| /* |
| * Do not set R1BIO_Uptodate if the current device is |
| * rebuilding or Faulty. This is because we cannot use |
| * such device for properly reading the data back (we could |
| * potentially use it, if the current write would have felt |
| * before rdev->recovery_offset, but for simplicity we don't |
| * check this here. |
| */ |
| if (test_bit(In_sync, &conf->mirrors[mirror].rdev->flags) && |
| !test_bit(Faulty, &conf->mirrors[mirror].rdev->flags)) |
| set_bit(R1BIO_Uptodate, &r1_bio->state); |
| |
| /* Maybe we can clear some bad blocks. */ |
| if (is_badblock(conf->mirrors[mirror].rdev, |
| r1_bio->sector, r1_bio->sectors, |
| &first_bad, &bad_sectors)) { |
| r1_bio->bios[mirror] = IO_MADE_GOOD; |
| set_bit(R1BIO_MadeGood, &r1_bio->state); |
| } |
| } |
| |
| if (behind) { |
| if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags)) |
| atomic_dec(&r1_bio->behind_remaining); |
| |
| /* |
| * In behind mode, we ACK the master bio once the I/O |
| * has safely reached all non-writemostly |
| * disks. Setting the Returned bit ensures that this |
| * gets done only once -- we don't ever want to return |
| * -EIO here, instead we'll wait |
| */ |
| if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) && |
| test_bit(R1BIO_Uptodate, &r1_bio->state)) { |
| /* Maybe we can return now */ |
| if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { |
| struct bio *mbio = r1_bio->master_bio; |
| pr_debug("raid1: behind end write sectors" |
| " %llu-%llu\n", |
| (unsigned long long) mbio->bi_iter.bi_sector, |
| (unsigned long long) bio_end_sector(mbio) - 1); |
| call_bio_endio(r1_bio); |
| } |
| } |
| } |
| if (r1_bio->bios[mirror] == NULL) |
| rdev_dec_pending(conf->mirrors[mirror].rdev, |
| conf->mddev); |
| |
| /* |
| * Let's see if all mirrored write operations have finished |
| * already. |
| */ |
| r1_bio_write_done(r1_bio); |
| |
| if (to_put) |
| bio_put(to_put); |
| } |
| |
| /* |
| * This routine returns the disk from which the requested read should |
| * be done. There is a per-array 'next expected sequential IO' sector |
| * number - if this matches on the next IO then we use the last disk. |
| * There is also a per-disk 'last know head position' sector that is |
| * maintained from IRQ contexts, both the normal and the resync IO |
| * completion handlers update this position correctly. If there is no |
| * perfect sequential match then we pick the disk whose head is closest. |
| * |
| * If there are 2 mirrors in the same 2 devices, performance degrades |
| * because position is mirror, not device based. |
| * |
| * The rdev for the device selected will have nr_pending incremented. |
| */ |
| static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors) |
| { |
| const sector_t this_sector = r1_bio->sector; |
| int sectors; |
| int best_good_sectors; |
| int best_disk, best_dist_disk, best_pending_disk; |
| int has_nonrot_disk; |
| int disk; |
| sector_t best_dist; |
| unsigned int min_pending; |
| struct md_rdev *rdev; |
| int choose_first; |
| int choose_next_idle; |
| |
| rcu_read_lock(); |
| /* |
| * Check if we can balance. We can balance on the whole |
| * device if no resync is going on, or below the resync window. |
| * We take the first readable disk when above the resync window. |
| */ |
| retry: |
| sectors = r1_bio->sectors; |
| best_disk = -1; |
| best_dist_disk = -1; |
| best_dist = MaxSector; |
| best_pending_disk = -1; |
| min_pending = UINT_MAX; |
| best_good_sectors = 0; |
| has_nonrot_disk = 0; |
| choose_next_idle = 0; |
| |
| if ((conf->mddev->recovery_cp < this_sector + sectors) || |
| (mddev_is_clustered(conf->mddev) && |
| md_cluster_ops->area_resyncing(conf->mddev, READ, this_sector, |
| this_sector + sectors))) |
| choose_first = 1; |
| else |
| choose_first = 0; |
| |
| for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) { |
| sector_t dist; |
| sector_t first_bad; |
| int bad_sectors; |
| unsigned int pending; |
| bool nonrot; |
| |
| rdev = rcu_dereference(conf->mirrors[disk].rdev); |
| if (r1_bio->bios[disk] == IO_BLOCKED |
| || rdev == NULL |
| || test_bit(Faulty, &rdev->flags)) |
| continue; |
| if (!test_bit(In_sync, &rdev->flags) && |
| rdev->recovery_offset < this_sector + sectors) |
| continue; |
| if (test_bit(WriteMostly, &rdev->flags)) { |
| /* Don't balance among write-mostly, just |
| * use the first as a last resort */ |
| if (best_dist_disk < 0) { |
| if (is_badblock(rdev, this_sector, sectors, |
| &first_bad, &bad_sectors)) { |
| if (first_bad <= this_sector) |
| /* Cannot use this */ |
| continue; |
| best_good_sectors = first_bad - this_sector; |
| } else |
| best_good_sectors = sectors; |
| best_dist_disk = disk; |
| best_pending_disk = disk; |
| } |
| continue; |
| } |
| /* This is a reasonable device to use. It might |
| * even be best. |
| */ |
| if (is_badblock(rdev, this_sector, sectors, |
| &first_bad, &bad_sectors)) { |
| if (best_dist < MaxSector) |
| /* already have a better device */ |
| continue; |
| if (first_bad <= this_sector) { |
| /* cannot read here. If this is the 'primary' |
| * device, then we must not read beyond |
| * bad_sectors from another device.. |
| */ |
| bad_sectors -= (this_sector - first_bad); |
| if (choose_first && sectors > bad_sectors) |
| sectors = bad_sectors; |
| if (best_good_sectors > sectors) |
| best_good_sectors = sectors; |
| |
| } else { |
| sector_t good_sectors = first_bad - this_sector; |
| if (good_sectors > best_good_sectors) { |
| best_good_sectors = good_sectors; |
| best_disk = disk; |
| } |
| if (choose_first) |
| break; |
| } |
| continue; |
| } else |
| best_good_sectors = sectors; |
| |
| nonrot = blk_queue_nonrot(bdev_get_queue(rdev->bdev)); |
| has_nonrot_disk |= nonrot; |
| pending = atomic_read(&rdev->nr_pending); |
| dist = abs(this_sector - conf->mirrors[disk].head_position); |
| if (choose_first) { |
| best_disk = disk; |
| break; |
| } |
| /* Don't change to another disk for sequential reads */ |
| if (conf->mirrors[disk].next_seq_sect == this_sector |
| || dist == 0) { |
| int opt_iosize = bdev_io_opt(rdev->bdev) >> 9; |
| struct raid1_info *mirror = &conf->mirrors[disk]; |
| |
| best_disk = disk; |
| /* |
| * If buffered sequential IO size exceeds optimal |
| * iosize, check if there is idle disk. If yes, choose |
| * the idle disk. read_balance could already choose an |
| * idle disk before noticing it's a sequential IO in |
| * this disk. This doesn't matter because this disk |
| * will idle, next time it will be utilized after the |
| * first disk has IO size exceeds optimal iosize. In |
| * this way, iosize of the first disk will be optimal |
| * iosize at least. iosize of the second disk might be |
| * small, but not a big deal since when the second disk |
| * starts IO, the first disk is likely still busy. |
| */ |
| if (nonrot && opt_iosize > 0 && |
| mirror->seq_start != MaxSector && |
| mirror->next_seq_sect > opt_iosize && |
| mirror->next_seq_sect - opt_iosize >= |
| mirror->seq_start) { |
| choose_next_idle = 1; |
| continue; |
| } |
| break; |
| } |
| /* If device is idle, use it */ |
| if (pending == 0) { |
| best_disk = disk; |
| break; |
| } |
| |
| if (choose_next_idle) |
| continue; |
| |
| if (min_pending > pending) { |
| min_pending = pending; |
| best_pending_disk = disk; |
| } |
| |
| if (dist < best_dist) { |
| best_dist = dist; |
| best_dist_disk = disk; |
| } |
| } |
| |
| /* |
| * If all disks are rotational, choose the closest disk. If any disk is |
| * non-rotational, choose the disk with less pending request even the |
| * disk is rotational, which might/might not be optimal for raids with |
| * mixed ratation/non-rotational disks depending on workload. |
| */ |
| if (best_disk == -1) { |
| if (has_nonrot_disk) |
| best_disk = best_pending_disk; |
| else |
| best_disk = best_dist_disk; |
| } |
| |
| if (best_disk >= 0) { |
| rdev = rcu_dereference(conf->mirrors[best_disk].rdev); |
| if (!rdev) |
| goto retry; |
| atomic_inc(&rdev->nr_pending); |
| if (test_bit(Faulty, &rdev->flags)) { |
| /* cannot risk returning a device that failed |
| * before we inc'ed nr_pending |
| */ |
| rdev_dec_pending(rdev, conf->mddev); |
| goto retry; |
| } |
| sectors = best_good_sectors; |
| |
| if (conf->mirrors[best_disk].next_seq_sect != this_sector) |
| conf->mirrors[best_disk].seq_start = this_sector; |
| |
| conf->mirrors[best_disk].next_seq_sect = this_sector + sectors; |
| } |
| rcu_read_unlock(); |
| *max_sectors = sectors; |
| |
| return best_disk; |
| } |
| |
| static int raid1_congested(struct mddev *mddev, int bits) |
| { |
| struct r1conf *conf = mddev->private; |
| int i, ret = 0; |
| |
| if ((bits & (1 << WB_async_congested)) && |
| conf->pending_count >= max_queued_requests) |
| return 1; |
| |
| rcu_read_lock(); |
| for (i = 0; i < conf->raid_disks * 2; i++) { |
| struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
| if (rdev && !test_bit(Faulty, &rdev->flags)) { |
| struct request_queue *q = bdev_get_queue(rdev->bdev); |
| |
| BUG_ON(!q); |
| |
| /* Note the '|| 1' - when read_balance prefers |
| * non-congested targets, it can be removed |
| */ |
| if ((bits & (1 << WB_async_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 void flush_pending_writes(struct r1conf *conf) |
| { |
| /* Any writes that have been queued but are awaiting |
| * bitmap updates get flushed here. |
| */ |
| spin_lock_irq(&conf->device_lock); |
| |
| if (conf->pending_bio_list.head) { |
| struct bio *bio; |
| bio = bio_list_get(&conf->pending_bio_list); |
| conf->pending_count = 0; |
| spin_unlock_irq(&conf->device_lock); |
| /* flush any pending bitmap writes to |
| * disk before proceeding w/ I/O */ |
| bitmap_unplug(conf->mddev->bitmap); |
| wake_up(&conf->wait_barrier); |
| |
| while (bio) { /* submit pending writes */ |
| struct bio *next = bio->bi_next; |
| bio->bi_next = NULL; |
| if (unlikely((bio->bi_rw & REQ_DISCARD) && |
| !blk_queue_discard(bdev_get_queue(bio->bi_bdev)))) |
| /* Just ignore it */ |
| bio_endio(bio); |
| else |
| generic_make_request(bio); |
| bio = next; |
| } |
| } else |
| spin_unlock_irq(&conf->device_lock); |
| } |
| |
| /* 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. |
| */ |
| static void raise_barrier(struct r1conf *conf, sector_t sector_nr) |
| { |
| 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); |
| |
| /* block any new IO from starting */ |
| conf->barrier++; |
| conf->next_resync = sector_nr; |
| |
| /* For these conditions we must wait: |
| * A: while the array is in frozen state |
| * B: while barrier >= RESYNC_DEPTH, meaning resync reach |
| * the max count which allowed. |
| * C: next_resync + RESYNC_SECTORS > start_next_window, meaning |
| * next resync will reach to the window which normal bios are |
| * handling. |
| * D: while there are any active requests in the current window. |
| */ |
| wait_event_lock_irq(conf->wait_barrier, |
| !conf->array_frozen && |
| conf->barrier < RESYNC_DEPTH && |
| conf->current_window_requests == 0 && |
| (conf->start_next_window >= |
| conf->next_resync + RESYNC_SECTORS), |
| conf->resync_lock); |
| |
| conf->nr_pending++; |
| spin_unlock_irq(&conf->resync_lock); |
| } |
| |
| static void lower_barrier(struct r1conf *conf) |
| { |
| unsigned long flags; |
| BUG_ON(conf->barrier <= 0); |
| spin_lock_irqsave(&conf->resync_lock, flags); |
| conf->barrier--; |
| conf->nr_pending--; |
| spin_unlock_irqrestore(&conf->resync_lock, flags); |
| wake_up(&conf->wait_barrier); |
| } |
| |
| static bool need_to_wait_for_sync(struct r1conf *conf, struct bio *bio) |
| { |
| bool wait = false; |
| |
| if (conf->array_frozen || !bio) |
| wait = true; |
| else if (conf->barrier && bio_data_dir(bio) == WRITE) { |
| if ((conf->mddev->curr_resync_completed |
| >= bio_end_sector(bio)) || |
| (conf->next_resync + NEXT_NORMALIO_DISTANCE |
| <= bio->bi_iter.bi_sector)) |
| wait = false; |
| else |
| wait = true; |
| } |
| |
| return wait; |
| } |
| |
| static sector_t wait_barrier(struct r1conf *conf, struct bio *bio) |
| { |
| sector_t sector = 0; |
| |
| spin_lock_irq(&conf->resync_lock); |
| if (need_to_wait_for_sync(conf, bio)) { |
| conf->nr_waiting++; |
| /* Wait for the barrier to drop. |
| * However if there are already pending |
| * requests (preventing the barrier from |
| * rising completely), and the |
| * per-process bio queue isn't empty, |
| * then don't wait, as we need to empty |
| * that queue to allow conf->start_next_window |
| * to increase. |
| */ |
| wait_event_lock_irq(conf->wait_barrier, |
| !conf->array_frozen && |
| (!conf->barrier || |
| ((conf->start_next_window < |
| conf->next_resync + RESYNC_SECTORS) && |
| current->bio_list && |
| (!bio_list_empty(¤t->bio_list[0]) || |
| !bio_list_empty(¤t->bio_list[1])))), |
| conf->resync_lock); |
| conf->nr_waiting--; |
| } |
| |
| if (bio && bio_data_dir(bio) == WRITE) { |
| if (bio->bi_iter.bi_sector >= conf->next_resync) { |
| if (conf->start_next_window == MaxSector) |
| conf->start_next_window = |
| conf->next_resync + |
| NEXT_NORMALIO_DISTANCE; |
| |
| if ((conf->start_next_window + NEXT_NORMALIO_DISTANCE) |
| <= bio->bi_iter.bi_sector) |
| conf->next_window_requests++; |
| else |
| conf->current_window_requests++; |
| sector = conf->start_next_window; |
| } |
| } |
| |
| conf->nr_pending++; |
| spin_unlock_irq(&conf->resync_lock); |
| return sector; |
| } |
| |
| static void allow_barrier(struct r1conf *conf, sector_t start_next_window, |
| sector_t bi_sector) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&conf->resync_lock, flags); |
| conf->nr_pending--; |
| if (start_next_window) { |
| if (start_next_window == conf->start_next_window) { |
| if (conf->start_next_window + NEXT_NORMALIO_DISTANCE |
| <= bi_sector) |
| conf->next_window_requests--; |
| else |
| conf->current_window_requests--; |
| } else |
| conf->current_window_requests--; |
| |
| if (!conf->current_window_requests) { |
| if (conf->next_window_requests) { |
| conf->current_window_requests = |
| conf->next_window_requests; |
| conf->next_window_requests = 0; |
| conf->start_next_window += |
| NEXT_NORMALIO_DISTANCE; |
| } else |
| conf->start_next_window = MaxSector; |
| } |
| } |
| spin_unlock_irqrestore(&conf->resync_lock, flags); |
| wake_up(&conf->wait_barrier); |
| } |
| |
| static void freeze_array(struct r1conf *conf, int extra) |
| { |
| /* stop syncio and normal IO and wait for everything to |
| * go quite. |
| * We wait until nr_pending match nr_queued+extra |
| * 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 (extra) |
| * must match the number of pending IOs (nr_pending) before |
| * we continue. |
| */ |
| spin_lock_irq(&conf->resync_lock); |
| conf->array_frozen = 1; |
| wait_event_lock_irq_cmd(conf->wait_barrier, |
| conf->nr_pending == conf->nr_queued+extra, |
| conf->resync_lock, |
| flush_pending_writes(conf)); |
| spin_unlock_irq(&conf->resync_lock); |
| } |
| static void unfreeze_array(struct r1conf *conf) |
| { |
| /* reverse the effect of the freeze */ |
| spin_lock_irq(&conf->resync_lock); |
| conf->array_frozen = 0; |
| wake_up(&conf->wait_barrier); |
| spin_unlock_irq(&conf->resync_lock); |
| } |
| |
| /* duplicate the data pages for behind I/O |
| */ |
| static void alloc_behind_pages(struct bio *bio, struct r1bio *r1_bio) |
| { |
| int i; |
| struct bio_vec *bvec; |
| struct bio_vec *bvecs = kzalloc(bio->bi_vcnt * sizeof(struct bio_vec), |
| GFP_NOIO); |
| if (unlikely(!bvecs)) |
| return; |
| |
| bio_for_each_segment_all(bvec, bio, i) { |
| bvecs[i] = *bvec; |
| bvecs[i].bv_page = alloc_page(GFP_NOIO); |
| if (unlikely(!bvecs[i].bv_page)) |
| goto do_sync_io; |
| memcpy(kmap(bvecs[i].bv_page) + bvec->bv_offset, |
| kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len); |
| kunmap(bvecs[i].bv_page); |
| kunmap(bvec->bv_page); |
| } |
| r1_bio->behind_bvecs = bvecs; |
| r1_bio->behind_page_count = bio->bi_vcnt; |
| set_bit(R1BIO_BehindIO, &r1_bio->state); |
| return; |
| |
| do_sync_io: |
| for (i = 0; i < bio->bi_vcnt; i++) |
| if (bvecs[i].bv_page) |
| put_page(bvecs[i].bv_page); |
| kfree(bvecs); |
| pr_debug("%dB behind alloc failed, doing sync I/O\n", |
| bio->bi_iter.bi_size); |
| } |
| |
| struct raid1_plug_cb { |
| struct blk_plug_cb cb; |
| struct bio_list pending; |
| int pending_cnt; |
| }; |
| |
| static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule) |
| { |
| struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb, |
| cb); |
| struct mddev *mddev = plug->cb.data; |
| struct r1conf *conf = mddev->private; |
| struct bio *bio; |
| |
| if (from_schedule || current->bio_list) { |
| spin_lock_irq(&conf->device_lock); |
| bio_list_merge(&conf->pending_bio_list, &plug->pending); |
| conf->pending_count += plug->pending_cnt; |
| spin_unlock_irq(&conf->device_lock); |
| wake_up(&conf->wait_barrier); |
| md_wakeup_thread(mddev->thread); |
| kfree(plug); |
| return; |
| } |
| |
| /* we aren't scheduling, so we can do the write-out directly. */ |
| bio = bio_list_get(&plug->pending); |
| bitmap_unplug(mddev->bitmap); |
| wake_up(&conf->wait_barrier); |
| |
| while (bio) { /* submit pending writes */ |
| struct bio *next = bio->bi_next; |
| bio->bi_next = NULL; |
| if (unlikely((bio->bi_rw & REQ_DISCARD) && |
| !blk_queue_discard(bdev_get_queue(bio->bi_bdev)))) |
| /* Just ignore it */ |
| bio_endio(bio); |
| else |
| generic_make_request(bio); |
| bio = next; |
| } |
| kfree(plug); |
| } |
| |
| static void make_request(struct mddev *mddev, struct bio * bio) |
| { |
| struct r1conf *conf = mddev->private; |
| struct raid1_info *mirror; |
| struct r1bio *r1_bio; |
| struct bio *read_bio; |
| int i, disks; |
| struct bitmap *bitmap; |
| unsigned long flags; |
| const int rw = bio_data_dir(bio); |
| const unsigned long do_sync = (bio->bi_rw & REQ_SYNC); |
| const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA)); |
| const unsigned long do_discard = (bio->bi_rw |
| & (REQ_DISCARD | REQ_SECURE)); |
| const unsigned long do_same = (bio->bi_rw & REQ_WRITE_SAME); |
| struct md_rdev *blocked_rdev; |
| struct blk_plug_cb *cb; |
| struct raid1_plug_cb *plug = NULL; |
| int first_clone; |
| int sectors_handled; |
| int max_sectors; |
| sector_t start_next_window; |
| |
| /* |
| * 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. |
| */ |
| |
| md_write_start(mddev, bio); /* wait on superblock update early */ |
| |
| if (bio_data_dir(bio) == WRITE && |
| ((bio_end_sector(bio) > mddev->suspend_lo && |
| bio->bi_iter.bi_sector < mddev->suspend_hi) || |
| (mddev_is_clustered(mddev) && |
| md_cluster_ops->area_resyncing(mddev, WRITE, |
| bio->bi_iter.bi_sector, bio_end_sector(bio))))) { |
| /* As the suspend_* range is controlled by |
| * userspace, we want an interruptible |
| * wait. |
| */ |
| DEFINE_WAIT(w); |
| for (;;) { |
| sigset_t full, old; |
| prepare_to_wait(&conf->wait_barrier, |
| &w, TASK_INTERRUPTIBLE); |
| if (bio_end_sector(bio) <= mddev->suspend_lo || |
| bio->bi_iter.bi_sector >= mddev->suspend_hi || |
| (mddev_is_clustered(mddev) && |
| !md_cluster_ops->area_resyncing(mddev, WRITE, |
| bio->bi_iter.bi_sector, bio_end_sector(bio)))) |
| break; |
| sigfillset(&full); |
| sigprocmask(SIG_BLOCK, &full, &old); |
| schedule(); |
| sigprocmask(SIG_SETMASK, &old, NULL); |
| } |
| finish_wait(&conf->wait_barrier, &w); |
| } |
| |
| start_next_window = wait_barrier(conf, bio); |
| |
| bitmap = mddev->bitmap; |
| |
| /* |
| * 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_sectors(bio); |
| r1_bio->state = 0; |
| r1_bio->mddev = mddev; |
| r1_bio->sector = bio->bi_iter.bi_sector; |
| |
| /* We might need to issue multiple reads to different |
| * devices if there are bad blocks around, so we keep |
| * track of the number of reads in bio->bi_phys_segments. |
| * If this is 0, there is only one r1_bio and no locking |
| * will be needed when requests complete. If it is |
| * non-zero, then it is the number of not-completed requests. |
| */ |
| bio->bi_phys_segments = 0; |
| bio_clear_flag(bio, BIO_SEG_VALID); |
| |
| if (rw == READ) { |
| /* |
| * read balancing logic: |
| */ |
| int rdisk; |
| |
| read_again: |
| rdisk = read_balance(conf, r1_bio, &max_sectors); |
| |
| if (rdisk < 0) { |
| /* couldn't find anywhere to read from */ |
| raid_end_bio_io(r1_bio); |
| return; |
| } |
| mirror = conf->mirrors + rdisk; |
| |
| if (test_bit(WriteMostly, &mirror->rdev->flags) && |
| bitmap) { |
| /* Reading from a write-mostly device must |
| * take care not to over-take any writes |
| * that are 'behind' |
| */ |
| wait_event(bitmap->behind_wait, |
| atomic_read(&bitmap->behind_writes) == 0); |
| } |
| r1_bio->read_disk = rdisk; |
| r1_bio->start_next_window = 0; |
| |
| read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev); |
| bio_trim(read_bio, r1_bio->sector - bio->bi_iter.bi_sector, |
| max_sectors); |
| |
| r1_bio->bios[rdisk] = read_bio; |
| |
| read_bio->bi_iter.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; |
| |
| if (max_sectors < r1_bio->sectors) { |
| /* could not read all from this device, so we will |
| * need another r1_bio. |
| */ |
| |
| sectors_handled = (r1_bio->sector + max_sectors |
| - bio->bi_iter.bi_sector); |
| r1_bio->sectors = max_sectors; |
| spin_lock_irq(&conf->device_lock); |
| if (bio->bi_phys_segments == 0) |
| bio->bi_phys_segments = 2; |
| else |
| bio->bi_phys_segments++; |
| spin_unlock_irq(&conf->device_lock); |
| /* Cannot call generic_make_request directly |
| * as that will be queued in __make_request |
| * and subsequent mempool_alloc might block waiting |
| * for it. So hand bio over to raid1d. |
| */ |
| reschedule_retry(r1_bio); |
| |
| r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
| |
| r1_bio->master_bio = bio; |
| r1_bio->sectors = bio_sectors(bio) - sectors_handled; |
| r1_bio->state = 0; |
| r1_bio->mddev = mddev; |
| r1_bio->sector = bio->bi_iter.bi_sector + |
| sectors_handled; |
| goto read_again; |
| } else |
| generic_make_request(read_bio); |
| return; |
| } |
| |
| /* |
| * WRITE: |
| */ |
| if (conf->pending_count >= max_queued_requests) { |
| md_wakeup_thread(mddev->thread); |
| wait_event(conf->wait_barrier, |
| conf->pending_count < max_queued_requests); |
| } |
| /* first select target devices under rcu_lock and |
| * inc refcount on their rdev. Record them by setting |
| * bios[x] to bio |
| * If there are known/acknowledged bad blocks on any device on |
| * which we have seen a write error, we want to avoid writing those |
| * blocks. |
| * This potentially requires several writes to write around |
| * the bad blocks. Each set of writes gets it's own r1bio |
| * with a set of bios attached. |
| */ |
| |
| disks = conf->raid_disks * 2; |
| retry_write: |
| r1_bio->start_next_window = start_next_window; |
| blocked_rdev = NULL; |
| rcu_read_lock(); |
| max_sectors = r1_bio->sectors; |
| for (i = 0; i < disks; i++) { |
| struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
| if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
| atomic_inc(&rdev->nr_pending); |
| blocked_rdev = rdev; |
| break; |
| } |
| r1_bio->bios[i] = NULL; |
| if (!rdev || test_bit(Faulty, &rdev->flags)) { |
| if (i < conf->raid_disks) |
| set_bit(R1BIO_Degraded, &r1_bio->state); |
| continue; |
| } |
| |
| atomic_inc(&rdev->nr_pending); |
| if (test_bit(WriteErrorSeen, &rdev->flags)) { |
| sector_t first_bad; |
| int bad_sectors; |
| int is_bad; |
| |
| is_bad = is_badblock(rdev, r1_bio->sector, |
| max_sectors, |
| &first_bad, &bad_sectors); |
| if (is_bad < 0) { |
| /* mustn't write here until the bad block is |
| * acknowledged*/ |
| set_bit(BlockedBadBlocks, &rdev->flags); |
| blocked_rdev = rdev; |
| break; |
| } |
| if (is_bad && first_bad <= r1_bio->sector) { |
| /* Cannot write here at all */ |
| bad_sectors -= (r1_bio->sector - first_bad); |
| if (bad_sectors < max_sectors) |
| /* mustn't write more than bad_sectors |
| * to other devices yet |
| */ |
| max_sectors = bad_sectors; |
| rdev_dec_pending(rdev, mddev); |
| /* We don't set R1BIO_Degraded as that |
| * only applies if the disk is |
| * missing, so it might be re-added, |
| * and we want to know to recover this |
| * chunk. |
| * In this case the device is here, |
| * and the fact that this chunk is not |
| * in-sync is recorded in the bad |
| * block log |
| */ |
| continue; |
| } |
| if (is_bad) { |
| int good_sectors = first_bad - r1_bio->sector; |
| if (good_sectors < max_sectors) |
| max_sectors = good_sectors; |
| } |
| } |
| r1_bio->bios[i] = bio; |
| } |
| rcu_read_unlock(); |
| |
| if (unlikely(blocked_rdev)) { |
| /* Wait for this device to become unblocked */ |
| int j; |
| sector_t old = start_next_window; |
| |
| for (j = 0; j < i; j++) |
| if (r1_bio->bios[j]) |
| rdev_dec_pending(conf->mirrors[j].rdev, mddev); |
| r1_bio->state = 0; |
| allow_barrier(conf, start_next_window, bio->bi_iter.bi_sector); |
| md_wait_for_blocked_rdev(blocked_rdev, mddev); |
| start_next_window = wait_barrier(conf, bio); |
| /* |
| * We must make sure the multi r1bios of bio have |
| * the same value of bi_phys_segments |
| */ |
| if (bio->bi_phys_segments && old && |
| old != start_next_window) |
| /* Wait for the former r1bio(s) to complete */ |
| wait_event(conf->wait_barrier, |
| bio->bi_phys_segments == 1); |
| goto retry_write; |
| } |
| |
| if (max_sectors < r1_bio->sectors) { |
| /* We are splitting this write into multiple parts, so |
| * we need to prepare for allocating another r1_bio. |
| */ |
| r1_bio->sectors = max_sectors; |
| spin_lock_irq(&conf->device_lock); |
| if (bio->bi_phys_segments == 0) |
| bio->bi_phys_segments = 2; |
| else |
| bio->bi_phys_segments++; |
| spin_unlock_irq(&conf->device_lock); |
| } |
| sectors_handled = r1_bio->sector + max_sectors - bio->bi_iter.bi_sector; |
| |
| atomic_set(&r1_bio->remaining, 1); |
| atomic_set(&r1_bio->behind_remaining, 0); |
| |
| first_clone = 1; |
| for (i = 0; i < disks; i++) { |
| struct bio *mbio; |
| if (!r1_bio->bios[i]) |
| continue; |
| |
| mbio = bio_clone_mddev(bio, GFP_NOIO, mddev); |
| bio_trim(mbio, r1_bio->sector - bio->bi_iter.bi_sector, max_sectors); |
| |
| if (first_clone) { |
| /* do behind I/O ? |
| * Not if there are too many, or cannot |
| * allocate memory, or a reader on WriteMostly |
| * is waiting for behind writes to flush */ |
| if (bitmap && |
| (atomic_read(&bitmap->behind_writes) |
| < mddev->bitmap_info.max_write_behind) && |
| !waitqueue_active(&bitmap->behind_wait)) |
| alloc_behind_pages(mbio, r1_bio); |
| |
| bitmap_startwrite(bitmap, r1_bio->sector, |
| r1_bio->sectors, |
| test_bit(R1BIO_BehindIO, |
| &r1_bio->state)); |
| first_clone = 0; |
| } |
| if (r1_bio->behind_bvecs) { |
| struct bio_vec *bvec; |
| int j; |
| |
| /* |
| * We trimmed the bio, so _all is legit |
| */ |
| bio_for_each_segment_all(bvec, mbio, j) |
| bvec->bv_page = r1_bio->behind_bvecs[j].bv_page; |
| if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags)) |
| atomic_inc(&r1_bio->behind_remaining); |
| } |
| |
| r1_bio->bios[i] = mbio; |
| |
| mbio->bi_iter.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_flush_fua | do_sync | do_discard | do_same; |
| mbio->bi_private = r1_bio; |
| |
| atomic_inc(&r1_bio->remaining); |
| |
| cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug)); |
| if (cb) |
| plug = container_of(cb, struct raid1_plug_cb, cb); |
| else |
| plug = NULL; |
| spin_lock_irqsave(&conf->device_lock, flags); |
| if (plug) { |
| bio_list_add(&plug->pending, mbio); |
| plug->pending_cnt++; |
| } else { |
| bio_list_add(&conf->pending_bio_list, mbio); |
| conf->pending_count++; |
| } |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| if (!plug) |
| md_wakeup_thread(mddev->thread); |
| } |
| /* Mustn't call r1_bio_write_done before this next test, |
| * as it could result in the bio being freed. |
| */ |
| if (sectors_handled < bio_sectors(bio)) { |
| r1_bio_write_done(r1_bio); |
| /* We need another r1_bio. It has already been counted |
| * in bio->bi_phys_segments |
| */ |
| r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
| r1_bio->master_bio = bio; |
| r1_bio->sectors = bio_sectors(bio) - sectors_handled; |
| r1_bio->state = 0; |
| r1_bio->mddev = mddev; |
| r1_bio->sector = bio->bi_iter.bi_sector + sectors_handled; |
| goto retry_write; |
| } |
| |
| r1_bio_write_done(r1_bio); |
| |
| /* In case raid1d snuck in to freeze_array */ |
| wake_up(&conf->wait_barrier); |
| } |
| |
| static void status(struct seq_file *seq, struct mddev *mddev) |
| { |
| struct r1conf *conf = mddev->private; |
| int i; |
| |
| seq_printf(seq, " [%d/%d] [", conf->raid_disks, |
| conf->raid_disks - mddev->degraded); |
| rcu_read_lock(); |
| for (i = 0; i < conf->raid_disks; i++) { |
| struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
| seq_printf(seq, "%s", |
| rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); |
| } |
| rcu_read_unlock(); |
| seq_printf(seq, "]"); |
| } |
| |
| static void error(struct mddev *mddev, struct md_rdev *rdev) |
| { |
| char b[BDEVNAME_SIZE]; |
| struct r1conf *conf = mddev->private; |
| unsigned long flags; |
| |
| /* |
| * 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. |
| * However don't try a recovery from this drive as |
| * it is very likely to fail. |
| */ |
| conf->recovery_disabled = mddev->recovery_disabled; |
| return; |
| } |
| set_bit(Blocked, &rdev->flags); |
| spin_lock_irqsave(&conf->device_lock, flags); |
| if (test_and_clear_bit(In_sync, &rdev->flags)) { |
| mddev->degraded++; |
| set_bit(Faulty, &rdev->flags); |
| } else |
| 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); |
| set_bit(MD_CHANGE_DEVS, &mddev->flags); |
| set_bit(MD_CHANGE_PENDING, &mddev->flags); |
| printk(KERN_ALERT |
| "md/raid1:%s: Disk failure on %s, disabling device.\n" |
| "md/raid1:%s: Operation continuing on %d devices.\n", |
| mdname(mddev), bdevname(rdev->bdev, b), |
| mdname(mddev), conf->raid_disks - mddev->degraded); |
| } |
| |
| static void print_conf(struct r1conf *conf) |
| { |
| int i; |
| |
| printk(KERN_DEBUG "RAID1 conf printout:\n"); |
| if (!conf) { |
| printk(KERN_DEBUG "(!conf)\n"); |
| return; |
| } |
| printk(KERN_DEBUG " --- 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]; |
| struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
| if (rdev) |
| printk(KERN_DEBUG " 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(struct r1conf *conf) |
| { |
| wait_barrier(conf, NULL); |
| allow_barrier(conf, 0, 0); |
| |
| mempool_destroy(conf->r1buf_pool); |
| conf->r1buf_pool = NULL; |
| |
| spin_lock_irq(&conf->resync_lock); |
| conf->next_resync = MaxSector - 2 * NEXT_NORMALIO_DISTANCE; |
| conf->start_next_window = MaxSector; |
| conf->current_window_requests += |
| conf->next_window_requests; |
| conf->next_window_requests = 0; |
| spin_unlock_irq(&conf->resync_lock); |
| } |
| |
| static int raid1_spare_active(struct mddev *mddev) |
| { |
| int i; |
| struct r1conf *conf = mddev->private; |
| int count = 0; |
| unsigned long flags; |
| |
| /* |
| * Find all failed disks within the RAID1 configuration |
| * and mark them readable. |
| * Called under mddev lock, so rcu protection not needed. |
| * device_lock used to avoid races with raid1_end_read_request |
| * which expects 'In_sync' flags and ->degraded to be consistent. |
| */ |
| spin_lock_irqsave(&conf->device_lock, flags); |
| for (i = 0; i < conf->raid_disks; i++) { |
| struct md_rdev *rdev = conf->mirrors[i].rdev; |
| struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev; |
| if (repl |
| && !test_bit(Candidate, &repl->flags) |
| && repl->recovery_offset == MaxSector |
| && !test_bit(Faulty, &repl->flags) |
| && !test_and_set_bit(In_sync, &repl->flags)) { |
| /* replacement has just become active */ |
| if (!rdev || |
| !test_and_clear_bit(In_sync, &rdev->flags)) |
| count++; |
| if (rdev) { |
| /* Replaced device not technically |
| * faulty, but we need to be sure |
| * it gets removed and never re-added |
| */ |
| set_bit(Faulty, &rdev->flags); |
| sysfs_notify_dirent_safe( |
| rdev->sysfs_state); |
| } |
| } |
| if (rdev |
| && rdev->recovery_offset == MaxSector |
| && !test_bit(Faulty, &rdev->flags) |
| && !test_and_set_bit(In_sync, &rdev->flags)) { |
| count++; |
| sysfs_notify_dirent_safe(rdev->sysfs_state); |
| } |
| } |
| mddev->degraded -= count; |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| |
| print_conf(conf); |
| return count; |
| } |
| |
| static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev) |
| { |
| struct r1conf *conf = mddev->private; |
| int err = -EEXIST; |
| int mirror = 0; |
| struct raid1_info *p; |
| int first = 0; |
| int last = conf->raid_disks - 1; |
| |
| if (mddev->recovery_disabled == conf->recovery_disabled) |
| return -EBUSY; |
| |
| if (md_integrity_add_rdev(rdev, mddev)) |
| return -ENXIO; |
| |
| if (rdev->raid_disk >= 0) |
| first = last = rdev->raid_disk; |
| |
| /* |
| * find the disk ... but prefer rdev->saved_raid_disk |
| * if possible. |
| */ |
| if (rdev->saved_raid_disk >= 0 && |
| rdev->saved_raid_disk >= first && |
| conf->mirrors[rdev->saved_raid_disk].rdev == NULL) |
| first = last = rdev->saved_raid_disk; |
| |
| for (mirror = first; mirror <= last; mirror++) { |
| p = conf->mirrors+mirror; |
| if (!p->rdev) { |
| |
| if (mddev->gendisk) |
| disk_stack_limits(mddev->gendisk, rdev->bdev, |
| rdev->data_offset << 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; |
| } |
| if (test_bit(WantReplacement, &p->rdev->flags) && |
| p[conf->raid_disks].rdev == NULL) { |
| /* Add this device as a replacement */ |
| clear_bit(In_sync, &rdev->flags); |
| set_bit(Replacement, &rdev->flags); |
| rdev->raid_disk = mirror; |
| err = 0; |
| conf->fullsync = 1; |
| rcu_assign_pointer(p[conf->raid_disks].rdev, rdev); |
| break; |
| } |
| } |
| if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev))) |
| queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); |
| print_conf(conf); |
| return err; |
| } |
| |
| static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev) |
| { |
| struct r1conf *conf = mddev->private; |
| int err = 0; |
| int number = rdev->raid_disk; |
| struct raid1_info *p = conf->mirrors + number; |
| |
| if (rdev != p->rdev) |
| p = conf->mirrors + conf->raid_disks + number; |
| |
| print_conf(conf); |
| if (rdev == p->rdev) { |
| if (test_bit(In_sync, &rdev->flags) || |
| atomic_read(&rdev->nr_pending)) { |
| err = -EBUSY; |
| goto abort; |
| } |
| /* Only remove non-faulty devices if recovery |
| * is not possible. |
| */ |
| if (!test_bit(Faulty, &rdev->flags) && |
| mddev->recovery_disabled != conf->recovery_disabled && |
| 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; |
| goto abort; |
| } else if (conf->mirrors[conf->raid_disks + number].rdev) { |
| /* We just removed a device that is being replaced. |
| * Move down the replacement. We drain all IO before |
| * doing this to avoid confusion. |
| */ |
| struct md_rdev *repl = |
| conf->mirrors[conf->raid_disks + number].rdev; |
| freeze_array(conf, 0); |
| if (atomic_read(&repl->nr_pending)) { |
| /* It means that some queued IO of retry_list |
| * hold repl. Thus, we cannot set replacement |
| * as NULL, avoiding rdev NULL pointer |
| * dereference in sync_request_write and |
| * handle_write_finished. |
| */ |
| err = -EBUSY; |
| unfreeze_array(conf); |
| goto abort; |
| } |
| clear_bit(Replacement, &repl->flags); |
| p->rdev = repl; |
| conf->mirrors[conf->raid_disks + number].rdev = NULL; |
| unfreeze_array(conf); |
| clear_bit(WantReplacement, &rdev->flags); |
| } else |
| clear_bit(WantReplacement, &rdev->flags); |
| err = md_integrity_register(mddev); |
| } |
| abort: |
| |
| print_conf(conf); |
| return err; |
| } |
| |
| static void end_sync_read(struct bio *bio) |
| { |
| struct r1bio *r1_bio = bio->bi_private; |
| |
| 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 (!bio->bi_error) |
| 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 uptodate = !bio->bi_error; |
| struct r1bio *r1_bio = bio->bi_private; |
| struct mddev *mddev = r1_bio->mddev; |
| struct r1conf *conf = mddev->private; |
| int mirror=0; |
| sector_t first_bad; |
| int bad_sectors; |
| |
| mirror = find_bio_disk(r1_bio, bio); |
| |
| if (!uptodate) { |
| sector_t 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); |
| set_bit(WriteErrorSeen, |
| &conf->mirrors[mirror].rdev->flags); |
| if (!test_and_set_bit(WantReplacement, |
| &conf->mirrors[mirror].rdev->flags)) |
| set_bit(MD_RECOVERY_NEEDED, & |
| mddev->recovery); |
| set_bit(R1BIO_WriteError, &r1_bio->state); |
| } else if (is_badblock(conf->mirrors[mirror].rdev, |
| r1_bio->sector, |
| r1_bio->sectors, |
| &first_bad, &bad_sectors) && |
| !is_badblock(conf->mirrors[r1_bio->read_disk].rdev, |
| r1_bio->sector, |
| r1_bio->sectors, |
| &first_bad, &bad_sectors) |
| ) |
| set_bit(R1BIO_MadeGood, &r1_bio->state); |
| |
| if (atomic_dec_and_test(&r1_bio->remaining)) { |
| int s = r1_bio->sectors; |
| if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
| test_bit(R1BIO_WriteError, &r1_bio->state)) |
| reschedule_retry(r1_bio); |
| else { |
| put_buf(r1_bio); |
| md_done_sync(mddev, s, uptodate); |
| } |
| } |
| } |
| |
| static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector, |
| int sectors, struct page *page, int rw) |
| { |
| if (sync_page_io(rdev, sector, sectors << 9, page, rw, false)) |
| /* success */ |
| return 1; |
| if (rw == WRITE) { |
| set_bit(WriteErrorSeen, &rdev->flags); |
| if (!test_and_set_bit(WantReplacement, |
| &rdev->flags)) |
| set_bit(MD_RECOVERY_NEEDED, & |
| rdev->mddev->recovery); |
| } |
| /* need to record an error - either for the block or the device */ |
| if (!rdev_set_badblocks(rdev, sector, sectors, 0)) |
| md_error(rdev->mddev, rdev); |
| return 0; |
| } |
| |
| static int fix_sync_read_error(struct r1bio *r1_bio) |
| { |
| /* 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. |
| * We don't need to check is_badblock() again as we |
| * made sure that anything with a bad block in range |
| * will have bi_end_io clear. |
| */ |
| struct mddev *mddev = r1_bio->mddev; |
| struct r1conf *conf = mddev->private; |
| struct bio *bio = r1_bio->bios[r1_bio->read_disk]; |
| 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; |
| struct md_rdev *rdev; |
| int start; |
| |
| 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, sect, s<<9, |
| bio->bi_io_vec[idx].bv_page, |
| READ, false)) { |
| success = 1; |
| break; |
| } |
| } |
| d++; |
| if (d == conf->raid_disks * 2) |
| d = 0; |
| } while (!success && d != r1_bio->read_disk); |
| |
| if (!success) { |
| char b[BDEVNAME_SIZE]; |
| int abort = 0; |
| /* Cannot read from anywhere, this block is lost. |
| * Record a bad block on each device. If that doesn't |
| * work just disable and interrupt the recovery. |
| * Don't fail devices as that won't really help. |
| */ |
| printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error" |
| " for block %llu\n", |
| mdname(mddev), |
| bdevname(bio->bi_bdev, b), |
| (unsigned long long)r1_bio->sector); |
| for (d = 0; d < conf->raid_disks * 2; d++) { |
| rdev = conf->mirrors[d].rdev; |
| if (!rdev || test_bit(Faulty, &rdev->flags)) |
| continue; |
| if (!rdev_set_badblocks(rdev, sect, s, 0)) |
| abort = 1; |
| } |
| if (abort) { |
| conf->recovery_disabled = |
| mddev->recovery_disabled; |
| set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
| md_done_sync(mddev, r1_bio->sectors, 0); |
| put_buf(r1_bio); |
| return 0; |
| } |
| /* Try next page */ |
| sectors -= s; |
| sect += s; |
| idx++; |
| continue; |
| } |
| |
| start = d; |
| /* write it back and re-read */ |
| while (d != r1_bio->read_disk) { |
| if (d == 0) |
| d = conf->raid_disks * 2; |
| d--; |
| if (r1_bio->bios[d]->bi_end_io != end_sync_read) |
| continue; |
| rdev = conf->mirrors[d].rdev; |
| if (r1_sync_page_io(rdev, sect, s, |
| bio->bi_io_vec[idx].bv_page, |
| WRITE) == 0) { |
| r1_bio->bios[d]->bi_end_io = NULL; |
| rdev_dec_pending(rdev, mddev); |
| } |
| } |
| d = start; |
| while (d != r1_bio->read_disk) { |
| if (d == 0) |
| d = conf->raid_disks * 2; |
| d--; |
| if (r1_bio->bios[d]->bi_end_io != end_sync_read) |
| continue; |
| rdev = conf->mirrors[d].rdev; |
| if (r1_sync_page_io(rdev, sect, s, |
| bio->bi_io_vec[idx].bv_page, |
| READ) != 0) |
| atomic_add(s, &rdev->corrected_errors); |
| } |
| sectors -= s; |
| sect += s; |
| idx ++; |
| } |
| set_bit(R1BIO_Uptodate, &r1_bio->state); |
| bio->bi_error = 0; |
| return 1; |
| } |
| |
| static void process_checks(struct r1bio *r1_bio) |
| { |
| /* 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 |
| */ |
| struct mddev *mddev = r1_bio->mddev; |
| struct r1conf *conf = mddev->private; |
| int primary; |
| int i; |
| int vcnt; |
| |
| /* Fix variable parts of all bios */ |
| vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9); |
| for (i = 0; i < conf->raid_disks * 2; i++) { |
| int j; |
| int size; |
| int error; |
| struct bio *b = r1_bio->bios[i]; |
| if (b->bi_end_io != end_sync_read) |
| continue; |
| /* fixup the bio for reuse, but preserve errno */ |
| error = b->bi_error; |
| bio_reset(b); |
| b->bi_error = error; |
| b->bi_vcnt = vcnt; |
| b->bi_iter.bi_size = r1_bio->sectors << 9; |
| b->bi_iter.bi_sector = r1_bio->sector + |
| conf->mirrors[i].rdev->data_offset; |
| b->bi_bdev = conf->mirrors[i].rdev->bdev; |
| b->bi_end_io = end_sync_read; |
| b->bi_private = r1_bio; |
| |
| size = b->bi_iter.bi_size; |
| for (j = 0; j < vcnt ; j++) { |
| struct bio_vec *bi; |
| bi = &b->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; |
| } |
| } |
| for (primary = 0; primary < conf->raid_disks * 2; primary++) |
| if (r1_bio->bios[primary]->bi_end_io == end_sync_read && |
| !r1_bio->bios[primary]->bi_error) { |
| 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 < conf->raid_disks * 2; i++) { |
| int j; |
| struct bio *pbio = r1_bio->bios[primary]; |
| struct bio *sbio = r1_bio->bios[i]; |
| int error = sbio->bi_error; |
| |
| if (sbio->bi_end_io != end_sync_read) |
| continue; |
| /* Now we can 'fixup' the error value */ |
| sbio->bi_error = 0; |
| |
| if (!error) { |
| 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), |
| sbio->bi_io_vec[j].bv_len)) |
| break; |
| } |
| } else |
| j = 0; |
| if (j >= 0) |
| atomic64_add(r1_bio->sectors, &mddev->resync_mismatches); |
| if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) |
| && !error)) { |
| /* No need to write to this device. */ |
| sbio->bi_end_io = NULL; |
| rdev_dec_pending(conf->mirrors[i].rdev, mddev); |
| continue; |
| } |
| |
| bio_copy_data(sbio, pbio); |
| } |
| } |
| |
| static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio) |
| { |
| struct r1conf *conf = mddev->private; |
| int i; |
| int disks = conf->raid_disks * 2; |
| struct bio *bio, *wbio; |
| |
| bio = r1_bio->bios[r1_bio->read_disk]; |
| |
| if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) |
| /* ouch - failed to read all of that. */ |
| if (!fix_sync_read_error(r1_bio)) |
| return; |
| |
| if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) |
| process_checks(r1_bio); |
| |
| /* |
| * 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, bio_sectors(wbio)); |
| |
| generic_make_request(wbio); |
| } |
| |
| if (atomic_dec_and_test(&r1_bio->remaining)) { |
| /* if we're here, all write(s) have completed, so clean up */ |
| int s = r1_bio->sectors; |
| if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
| test_bit(R1BIO_WriteError, &r1_bio->state)) |
| reschedule_retry(r1_bio); |
| else { |
| put_buf(r1_bio); |
| md_done_sync(mddev, s, 1); |
| } |
| } |
| } |
| |
| /* |
| * 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 synchronising. |
| */ |
| |
| static void fix_read_error(struct r1conf *conf, int read_disk, |
| sector_t sect, int sectors) |
| { |
| struct mddev *mddev = conf->mddev; |
| while(sectors) { |
| int s = sectors; |
| int d = read_disk; |
| int success = 0; |
| int start; |
| struct md_rdev *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.... |
| */ |
| sector_t first_bad; |
| int bad_sectors; |
| |
| rdev = conf->mirrors[d].rdev; |
| if (rdev && |
| (test_bit(In_sync, &rdev->flags) || |
| (!test_bit(Faulty, &rdev->flags) && |
| rdev->recovery_offset >= sect + s)) && |
| is_badblock(rdev, sect, s, |
| &first_bad, &bad_sectors) == 0 && |
| sync_page_io(rdev, sect, s<<9, |
| conf->tmppage, READ, false)) |
| success = 1; |
| else { |
| d++; |
| if (d == conf->raid_disks * 2) |
| d = 0; |
| } |
| } while (!success && d != read_disk); |
| |
| if (!success) { |
| /* Cannot read from anywhere - mark it bad */ |
| struct md_rdev *rdev = conf->mirrors[read_disk].rdev; |
| if (!rdev_set_badblocks(rdev, sect, s, 0)) |
| md_error(mddev, rdev); |
| break; |
| } |
| /* write it back and re-read */ |
| start = d; |
| while (d != read_disk) { |
| if (d==0) |
| d = conf->raid_disks * 2; |
| d--; |
| rdev = conf->mirrors[d].rdev; |
| if (rdev && |
| !test_bit(Faulty, &rdev->flags)) |
| r1_sync_page_io(rdev, sect, s, |
| conf->tmppage, WRITE); |
| } |
| d = start; |
| while (d != read_disk) { |
| char b[BDEVNAME_SIZE]; |
| if (d==0) |
| d = conf->raid_disks * 2; |
| d--; |
| rdev = conf->mirrors[d].rdev; |
| if (rdev && |
| !test_bit(Faulty, &rdev->flags)) { |
| if (r1_sync_page_io(rdev, sect, s, |
| conf->tmppage, READ)) { |
| atomic_add(s, &rdev->corrected_errors); |
| printk(KERN_INFO |
| "md/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 int narrow_write_error(struct r1bio *r1_bio, int i) |
| { |
| struct mddev *mddev = r1_bio->mddev; |
| struct r1conf *conf = mddev->private; |
| struct md_rdev *rdev = conf->mirrors[i].rdev; |
| |
| /* bio has the data to be written to device 'i' where |
| * we just recently had a write error. |
| * We repeatedly clone the bio and trim down to one block, |
| * then try the write. Where the write fails we record |
| * a bad block. |
| * It is conceivable that the bio doesn't exactly align with |
| * blocks. We must handle this somehow. |
| * |
| * We currently own a reference on the rdev. |
| */ |
| |
| int block_sectors; |
| sector_t sector; |
| int sectors; |
| int sect_to_write = r1_bio->sectors; |
| int ok = 1; |
| |
| if (rdev->badblocks.shift < 0) |
| return 0; |
| |
| block_sectors = roundup(1 << rdev->badblocks.shift, |
| bdev_logical_block_size(rdev->bdev) >> 9); |
| sector = r1_bio->sector; |
| sectors = ((sector + block_sectors) |
| & ~(sector_t)(block_sectors - 1)) |
| - sector; |
| |
| while (sect_to_write) { |
| struct bio *wbio; |
| if (sectors > sect_to_write) |
| sectors = sect_to_write; |
| /* Write at 'sector' for 'sectors'*/ |
| |
| if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { |
| unsigned vcnt = r1_bio->behind_page_count; |
| struct bio_vec *vec = r1_bio->behind_bvecs; |
| |
| while (!vec->bv_page) { |
| vec++; |
| vcnt--; |
| } |
| |
| wbio = bio_alloc_mddev(GFP_NOIO, vcnt, mddev); |
| memcpy(wbio->bi_io_vec, vec, vcnt * sizeof(struct bio_vec)); |
| |
| wbio->bi_vcnt = vcnt; |
| } else { |
| wbio = bio_clone_mddev(r1_bio->master_bio, GFP_NOIO, mddev); |
| } |
| |
| wbio->bi_rw = WRITE; |
| wbio->bi_iter.bi_sector = r1_bio->sector; |
| wbio->bi_iter.bi_size = r1_bio->sectors << 9; |
| |
| bio_trim(wbio, sector - r1_bio->sector, sectors); |
| wbio->bi_iter.bi_sector += rdev->data_offset; |
| wbio->bi_bdev = rdev->bdev; |
| if (submit_bio_wait(WRITE, wbio) < 0) |
| /* failure! */ |
| ok = rdev_set_badblocks(rdev, sector, |
| sectors, 0) |
| && ok; |
| |
| bio_put(wbio); |
| sect_to_write -= sectors; |
| sector += sectors; |
| sectors = block_sectors; |
| } |
| return ok; |
| } |
| |
| static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio) |
| { |
| int m; |
| int s = r1_bio->sectors; |
| for (m = 0; m < conf->raid_disks * 2 ; m++) { |
| struct md_rdev *rdev = conf->mirrors[m].rdev; |
| struct bio *bio = r1_bio->bios[m]; |
| if (bio->bi_end_io == NULL) |
| continue; |
| if (!bio->bi_error && |
| test_bit(R1BIO_MadeGood, &r1_bio->state)) { |
| rdev_clear_badblocks(rdev, r1_bio->sector, s, 0); |
| } |
| if (bio->bi_error && |
| test_bit(R1BIO_WriteError, &r1_bio->state)) { |
| if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0)) |
| md_error(conf->mddev, rdev); |
| } |
| } |
| put_buf(r1_bio); |
| md_done_sync(conf->mddev, s, 1); |
| } |
| |
| static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio) |
| { |
| int m; |
| bool fail = false; |
| for (m = 0; m < conf->raid_disks * 2 ; m++) |
| if (r1_bio->bios[m] == IO_MADE_GOOD) { |
| struct md_rdev *rdev = conf->mirrors[m].rdev; |
| rdev_clear_badblocks(rdev, |
| r1_bio->sector, |
| r1_bio->sectors, 0); |
| rdev_dec_pending(rdev, conf->mddev); |
| } else if (r1_bio->bios[m] != NULL) { |
| /* This drive got a write error. We need to |
| * narrow down and record precise write |
| * errors. |
| */ |
| fail = true; |
| if (!narrow_write_error(r1_bio, m)) { |
| md_error(conf->mddev, |
| conf->mirrors[m].rdev); |
| /* an I/O failed, we can't clear the bitmap */ |
| set_bit(R1BIO_Degraded, &r1_bio->state); |
| } |
| rdev_dec_pending(conf->mirrors[m].rdev, |
| conf->mddev); |
| } |
| if (fail) { |
| spin_lock_irq(&conf->device_lock); |
| list_add(&r1_bio->retry_list, &conf->bio_end_io_list); |
| conf->nr_queued++; |
| spin_unlock_irq(&conf->device_lock); |
| md_wakeup_thread(conf->mddev->thread); |
| } else { |
| if (test_bit(R1BIO_WriteError, &r1_bio->state)) |
| close_write(r1_bio); |
| raid_end_bio_io(r1_bio); |
| } |
| } |
| |
| static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio) |
| { |
| int disk; |
| int max_sectors; |
| struct mddev *mddev = conf->mddev; |
| struct bio *bio; |
| char b[BDEVNAME_SIZE]; |
| struct md_rdev *rdev; |
| |
| clear_bit(R1BIO_ReadError, &r1_bio->state); |
| /* 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, 1); |
| fix_read_error(conf, r1_bio->read_disk, |
| r1_bio->sector, r1_bio->sectors); |
| unfreeze_array(conf); |
| } else |
| md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); |
| rdev_dec_pending(conf->mirrors[r1_bio->read_disk].rdev, conf->mddev); |
| |
| bio = r1_bio->bios[r1_bio->read_disk]; |
| bdevname(bio->bi_bdev, b); |
| read_more: |
| disk = read_balance(conf, r1_bio, &max_sectors); |
| if (disk == -1) { |
| printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O" |
| " read error for block %llu\n", |
| mdname(mddev), b, (unsigned long long)r1_bio->sector); |
| raid_end_bio_io(r1_bio); |
| } else { |
| const unsigned long do_sync |
| = r1_bio->master_bio->bi_rw & REQ_SYNC; |
| if (bio) { |
| r1_bio->bios[r1_bio->read_disk] = |
| mddev->ro ? IO_BLOCKED : NULL; |
| bio_put(bio); |
| } |
| r1_bio->read_disk = disk; |
| bio = bio_clone_mddev(r1_bio->master_bio, GFP_NOIO, mddev); |
| bio_trim(bio, r1_bio->sector - bio->bi_iter.bi_sector, |
| max_sectors); |
| r1_bio->bios[r1_bio->read_disk] = bio; |
| rdev = conf->mirrors[disk].rdev; |
| printk_ratelimited(KERN_ERR |
| "md/raid1:%s: redirecting sector %llu" |
| " to other mirror: %s\n", |
| mdname(mddev), |
| (unsigned long long)r1_bio->sector, |
| bdevname(rdev->bdev, b)); |
| bio->bi_iter.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; |
| if (max_sectors < r1_bio->sectors) { |
| /* Drat - have to split this up more */ |
| struct bio *mbio = r1_bio->master_bio; |
| int sectors_handled = (r1_bio->sector + max_sectors |
| - mbio->bi_iter.bi_sector); |
| r1_bio->sectors = max_sectors; |
| spin_lock_irq(&conf->device_lock); |
| if (mbio->bi_phys_segments == 0) |
| mbio->bi_phys_segments = 2; |
| else |
| mbio->bi_phys_segments++; |
| spin_unlock_irq(&conf->device_lock); |
| generic_make_request(bio); |
| bio = NULL; |
| |
| r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
| |
| r1_bio->master_bio = mbio; |
| r1_bio->sectors = bio_sectors(mbio) - sectors_handled; |
| r1_bio->state = 0; |
| set_bit(R1BIO_ReadError, &r1_bio->state); |
| r1_bio->mddev = mddev; |
| r1_bio->sector = mbio->bi_iter.bi_sector + |
| sectors_handled; |
| |
| goto read_more; |
| } else |
| generic_make_request(bio); |
| } |
| } |
| |
| static void raid1d(struct md_thread *thread) |
| { |
| struct mddev *mddev = thread->mddev; |
| struct r1bio *r1_bio; |
| unsigned long flags; |
| struct r1conf *conf = mddev->private; |
| struct list_head *head = &conf->retry_list; |
| struct blk_plug plug; |
| |
| md_check_recovery(mddev); |
| |
| if (!list_empty_careful(&conf->bio_end_io_list) && |
| !test_bit(MD_CHANGE_PENDING, &mddev->flags)) { |
| LIST_HEAD(tmp); |
| spin_lock_irqsave(&conf->device_lock, flags); |
| if (!test_bit(MD_CHANGE_PENDING, &mddev->flags)) { |
| while (!list_empty(&conf->bio_end_io_list)) { |
| list_move(conf->bio_end_io_list.prev, &tmp); |
| conf->nr_queued--; |
| } |
| } |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| while (!list_empty(&tmp)) { |
| r1_bio = list_first_entry(&tmp, struct r1bio, |
| retry_list); |
| list_del(&r1_bio->retry_list); |
| if (mddev->degraded) |
| set_bit(R1BIO_Degraded, &r1_bio->state); |
| if (test_bit(R1BIO_WriteError, &r1_bio->state)) |
| close_write(r1_bio); |
| raid_end_bio_io(r1_bio); |
| } |
| } |
| |
| blk_start_plug(&plug); |
| for (;;) { |
| |
| 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, struct r1bio, retry_list); |
| list_del(head->prev); |
| conf->nr_queued--; |
| spin_unlock_irqrestore(&conf->device_lock, flags); |
| |
| mddev = r1_bio->mddev; |
| conf = mddev->private; |
| if (test_bit(R1BIO_IsSync, &r1_bio->state)) { |
| if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
| test_bit(R1BIO_WriteError, &r1_bio->state)) |
| handle_sync_write_finished(conf, r1_bio); |
| else |
| sync_request_write(mddev, r1_bio); |
| } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
| test_bit(R1BIO_WriteError, &r1_bio->state)) |
| handle_write_finished(conf, r1_bio); |
| else if (test_bit(R1BIO_ReadError, &r1_bio->state)) |
| handle_read_error(conf, r1_bio); |
| else |
| /* just a partial read to be scheduled from separate |
| * context |
| */ |
| generic_make_request(r1_bio->bios[r1_bio->read_disk]); |
| |
| cond_resched(); |
| if (mddev->flags & ~(1<<MD_CHANGE_PENDING)) |
| md_check_recovery(mddev); |
| } |
| blk_finish_plug(&plug); |
| } |
| |
| static int init_resync(struct r1conf *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(struct mddev *mddev, sector_t sector_nr, int *skipped) |
| { |
| struct r1conf *conf = mddev->private; |
| struct r1bio *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; |
| sector_t sync_blocks; |
| int still_degraded = 0; |
| int good_sectors = RESYNC_SECTORS; |
| int min_bad = 0; /* number of sectors that are bad in all devices */ |
| |
| if (!conf->r1buf_pool) |
| if (init_resync(conf)) |
| return 0; |
| |
| max_sector = mddev->dev_sectors; |
| 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); |
| |
| if (mddev_is_clustered(mddev)) { |
| conf->cluster_sync_low = 0; |
| conf->cluster_sync_high = 0; |
| } |
| 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; |
| } |
| |
| /* we are incrementing sector_nr below. To be safe, we check against |
| * sector_nr + two times RESYNC_SECTORS |
| */ |
| |
| bitmap_cond_end_sync(mddev->bitmap, sector_nr, |
| mddev_is_clustered(mddev) && (sector_nr + 2 * RESYNC_SECTORS > conf->cluster_sync_high)); |
| r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO); |
| |
| raise_barrier(conf, sector_nr); |
| |
| 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 * 2; i++) { |
| struct md_rdev *rdev; |
| bio = r1_bio->bios[i]; |
| bio_reset(bio); |
| |
| rdev = rcu_dereference(conf->mirrors[i].rdev); |
| if (rdev == NULL || |
| test_bit(Faulty, &rdev->flags)) { |
| if (i < conf->raid_disks) |
| still_degraded = 1; |
| } 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 */ |
| sector_t first_bad = MaxSector; |
| int bad_sectors; |
| |
| if (is_badblock(rdev, sector_nr, good_sectors, |
| &first_bad, &bad_sectors)) { |
| if (first_bad > sector_nr) |
| good_sectors = first_bad - sector_nr; |
| else { |
| bad_sectors -= (sector_nr - first_bad); |
| if (min_bad == 0 || |
| min_bad > bad_sectors) |
| min_bad = bad_sectors; |
| } |
| } |
| if (sector_nr < first_bad) { |
| if (test_bit(WriteMostly, &rdev->flags)) { |
| if (wonly < 0) |
| wonly = i; |
| } else { |
| if (disk < 0) |
| disk = i; |
| } |
| bio->bi_rw = READ; |
| bio->bi_end_io = end_sync_read; |
| read_targets++; |
| } else if (!test_bit(WriteErrorSeen, &rdev->flags) && |
| test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && |
| !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) { |
| /* |
| * The device is suitable for reading (InSync), |
| * but has bad block(s) here. Let's try to correct them, |
| * if we are doing resync or repair. Otherwise, leave |
| * this device alone for this sync request. |
| */ |
| bio->bi_rw = WRITE; |
| bio->bi_end_io = end_sync_write; |
| write_targets++; |
| } |
| } |
| if (bio->bi_end_io) { |
| atomic_inc(&rdev->nr_pending); |
| bio->bi_iter.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 (read_targets == 0 && min_bad > 0) { |
| /* These sectors are bad on all InSync devices, so we |
| * need to mark them bad on all write targets |
| */ |
| int ok = 1; |
| for (i = 0 ; i < conf->raid_disks * 2 ; i++) |
| if (r1_bio->bios[i]->bi_end_io == end_sync_write) { |
| struct md_rdev *rdev = conf->mirrors[i].rdev; |
| ok = rdev_set_badblocks(rdev, sector_nr, |
| min_bad, 0 |
| ) && ok; |
| } |
| set_bit(MD_CHANGE_DEVS, &mddev->flags); |
| *skipped = 1; |
| put_buf(r1_bio); |
| |
| if (!ok) { |
| /* Cannot record the badblocks, so need to |
| * abort the resync. |
| * If there are multiple read targets, could just |
| * fail the really bad ones ??? |
| */ |
| conf->recovery_disabled = mddev->recovery_disabled; |
| set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
| return 0; |
| } else |
| return min_bad; |
| |
| } |
| if (min_bad > 0 && min_bad < good_sectors) { |
| /* only resync enough to reach the next bad->good |
| * transition */ |
| good_sectors = min_bad; |
| } |
| |
| 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; |
| if (min_bad > 0) |
| max_sector = sector_nr + min_bad; |
| 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 */ |
| if (max_sector > sector_nr + good_sectors) |
| max_sector = sector_nr + good_sectors; |
| 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 >> 9) > sync_blocks) |
| len = sync_blocks<<9; |
| } |
| |
| for (i = 0 ; i < conf->raid_disks * 2; 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_iter.bi_size -= len; |
| bio_clear_flag(bio, 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; |
| |
| if (mddev_is_clustered(mddev) && |
| conf->cluster_sync_high < sector_nr + nr_sectors) { |
| conf->cluster_sync_low = mddev->curr_resync_completed; |
| conf->cluster_sync_high = conf->cluster_sync_low + CLUSTER_RESYNC_WINDOW_SECTORS; |
| /* Send resync message */ |
| md_cluster_ops->resync_info_update(mddev, |
| conf->cluster_sync_low, |
| conf->cluster_sync_high); |
| } |
| |
| /* 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 * 2 && read_targets; i++) { |
| bio = r1_bio->bios[i]; |
| if (bio->bi_end_io == end_sync_read) { |
| read_targets--; |
| 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 sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks) |
| { |
| if (sectors) |
| return sectors; |
| |
| return mddev->dev_sectors; |
| } |
| |
| static struct r1conf *setup_conf(struct mddev *mddev) |
| { |
| struct r1conf *conf; |
| int i; |
| struct raid1_info *disk; |
| struct md_rdev *rdev; |
| int err = -ENOMEM; |
| |
| conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL); |
| if (!conf) |
| goto abort; |
| |
| conf->mirrors = kzalloc(sizeof(struct raid1_info) |
| * mddev->raid_disks * 2, |
| GFP_KERNEL); |
| if (!conf->mirrors) |
| goto abort; |
| |
| conf->tmppage = alloc_page(GFP_KERNEL); |
| if (!conf->tmppage) |
| goto abort; |
| |
| conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL); |
| if (!conf->poolinfo) |
| goto abort; |
| conf->poolinfo->raid_disks = mddev->raid_disks * 2; |
| conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, |
| r1bio_pool_free, |
| conf->poolinfo); |
| if (!conf->r1bio_pool) |
| goto abort; |
| |
| conf->poolinfo->mddev = mddev; |
| |
| err = -EINVAL; |
| spin_lock_init(&conf->device_lock); |
| rdev_for_each(rdev, mddev) { |
| struct request_queue *q; |
| int disk_idx = rdev->raid_disk; |
| if (disk_idx >= mddev->raid_disks |
| || disk_idx < 0) |
| continue; |
| if (test_bit(Replacement, &rdev->flags)) |
| disk = conf->mirrors + mddev->raid_disks + disk_idx; |
| else |
| disk = conf->mirrors + disk_idx; |
| |
| if (disk->rdev) |
| goto abort; |
| disk->rdev = rdev; |
| q = bdev_get_queue(rdev->bdev); |
| |
| disk->head_position = 0; |
| disk->seq_start = MaxSector; |
| } |
| conf->raid_disks = mddev->raid_disks; |
| conf->mddev = mddev; |
| INIT_LIST_HEAD(&conf->retry_list); |
| INIT_LIST_HEAD(&conf->bio_end_io_list); |
| |
| spin_lock_init(&conf->resync_lock); |
| init_waitqueue_head(&conf->wait_barrier); |
| |
| bio_list_init(&conf->pending_bio_list); |
| conf->pending_count = 0; |
| conf->recovery_disabled = mddev->recovery_disabled - 1; |
| |
| conf->start_next_window = MaxSector; |
| conf->current_window_requests = conf->next_window_requests = 0; |
| |
| err = -EIO; |
| for (i = 0; i < conf->raid_disks * 2; i++) { |
| |
| disk = conf->mirrors + i; |
| |
| if (i < conf->raid_disks && |
| disk[conf->raid_disks].rdev) { |
| /* This slot has a replacement. */ |
| if (!disk->rdev) { |
| /* No original, just make the replacement |
| * a recovering spare |
| */ |
| disk->rdev = |
| disk[conf->raid_disks].rdev; |
| disk[conf->raid_disks].rdev = NULL; |
| } else if (!test_bit(In_sync, &disk->rdev->flags)) |
| /* Original is not in_sync - bad */ |
| goto abort; |
| } |
| |
| if (!disk->rdev || |
| !test_bit(In_sync, &disk->rdev->flags)) { |
| disk->head_position = 0; |
| if (disk->rdev && |
| (disk->rdev->saved_raid_disk < 0)) |
| conf->fullsync = 1; |
| } |
| } |
| |
| err = -ENOMEM; |
| conf->thread = md_register_thread(raid1d, mddev, "raid1"); |
| if (!conf->thread) { |
| printk(KERN_ERR |
| "md/raid1:%s: couldn't allocate thread\n", |
| mdname(mddev)); |
| goto abort; |
| } |
| |
| return conf; |
| |
| abort: |
| if (conf) { |
| mempool_destroy(conf->r1bio_pool); |
| kfree(conf->mirrors); |
| safe_put_page(conf->tmppage); |
| kfree(conf->poolinfo); |
| kfree(conf); |
| } |
| return ERR_PTR(err); |
| } |
| |
| static void raid1_free(struct mddev *mddev, void *priv); |
| static int run(struct mddev *mddev) |
| { |
| struct r1conf *conf; |
| int i; |
| struct md_rdev *rdev; |
| int ret; |
| bool discard_supported = false; |
| |
| if (mddev->level != 1) { |
| printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n", |
| mdname(mddev), mddev->level); |
| return -EIO; |
| } |
| if (mddev->reshape_position != MaxSector) { |
| printk(KERN_ERR "md/raid1:%s: reshape_position set but not supported\n", |
| mdname(mddev)); |
| return -EIO; |
| } |
| /* |
| * copy the already verified devices into our private RAID1 |
| * bookkeeping area. [whatever we allocate in run(), |
| * should be freed in raid1_free()] |
| */ |
| if (mddev->private == NULL) |
| conf = setup_conf(mddev); |
| else |
| conf = mddev->private; |
| |
| if (IS_ERR(conf)) |
| return PTR_ERR(conf); |
| |
| if (mddev->queue) |
| blk_queue_max_write_same_sectors(mddev->queue, 0); |
| |
| rdev_for_each(rdev, mddev) { |
| if (!mddev->gendisk) |
| continue; |
| disk_stack_limits(mddev->gendisk, rdev->bdev, |
| rdev->data_offset << 9); |
| if (blk_queue_discard(bdev_get_queue(rdev->bdev))) |
| discard_supported = true; |
| } |
| |
| mddev->degraded = 0; |
| for (i=0; i < conf->raid_disks; i++) |
| if (conf->mirrors[i].rdev == NULL || |
| !test_bit(In_sync, &conf->mirrors[i].rdev->flags) || |
| test_bit(Faulty, &conf->mirrors[i].rdev->flags)) |
| mddev->degraded++; |
| |
| if (conf->raid_disks - mddev->degraded == 1) |
| mddev->recovery_cp = MaxSector; |
| |
| if (mddev->recovery_cp != MaxSector) |
| printk(KERN_NOTICE "md/raid1:%s: not clean" |
| " -- starting background reconstruction\n", |
| mdname(mddev)); |
| printk(KERN_INFO |
| "md/raid1:%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->thread = conf->thread; |
| conf->thread = NULL; |
| mddev->private = conf; |
| |
| md_set_array_sectors(mddev, raid1_size(mddev, 0, 0)); |
| |
| if (mddev->queue) { |
| if (discard_supported) |
| queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, |
| mddev->queue); |
| else |
| queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, |
| mddev->queue); |
| } |
| |
| ret = md_integrity_register(mddev); |
| if (ret) { |
| md_unregister_thread(&mddev->thread); |
| raid1_free(mddev, conf); |
| } |
| return ret; |
| } |
| |
| static void raid1_free(struct mddev *mddev, void *priv) |
| { |
| struct r1conf *conf = priv; |
| |
| mempool_destroy(conf->r1bio_pool); |
| kfree(conf->mirrors); |
| safe_put_page(conf->tmppage); |
| kfree(conf->poolinfo); |
| kfree(conf); |
| } |
| |
| static int raid1_resize(struct mddev *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. |
| */ |
| sector_t newsize = raid1_size(mddev, sectors, 0); |
| if (mddev->external_size && |
| mddev->array_sectors > newsize) |
| return -EINVAL; |
| if (mddev->bitmap) { |
| int ret = bitmap_resize(mddev->bitmap, newsize, 0, 0); |
| if (ret) |
| return ret; |
| } |
| md_set_array_sectors(mddev, newsize); |
| set_capacity(mddev->gendisk, mddev->array_sectors); |
| revalidate_disk(mddev->gendisk); |
| if (sectors > mddev->dev_sectors && |
| mddev->recovery_cp > mddev->dev_sectors) { |
| mddev->recovery_cp = mddev->dev_sectors; |
| set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
| } |
| mddev->dev_sectors = sectors; |
| mddev->resync_max_sectors = sectors; |
| return 0; |
| } |
| |
| static int raid1_reshape(struct mddev *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; |
| struct raid1_info *newmirrors; |
| struct r1conf *conf = mddev->private; |
| int cnt, raid_disks; |
| unsigned long flags; |
| int d, d2, err; |
| |
| /* Cannot change chunk_size, layout, or level */ |
| if (mddev->chunk_sectors != mddev->new_chunk_sectors || |
| mddev->layout != mddev->new_layout || |
| mddev->level != mddev->new_level) { |
| mddev->new_chunk_sectors = mddev->chunk_sectors; |
| mddev->new_layout = mddev->layout; |
| mddev->new_level = mddev->level; |
| return -EINVAL; |
| } |
| |
| if (!mddev_is_clustered(mddev)) { |
| 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 * 2; |
| |
| newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, |
| r1bio_pool_free, newpoolinfo); |
| if (!newpool) { |
| kfree(newpoolinfo); |
| return -ENOMEM; |
| } |
| newmirrors = kzalloc(sizeof(struct raid1_info) * raid_disks * 2, |
| GFP_KERNEL); |
| if (!newmirrors) { |
| kfree(newpoolinfo); |
| mempool_destroy(newpool); |
| return -ENOMEM; |
| } |
| |
| freeze_array(conf, 0); |
| |
| /* ok, everything is stopped */ |
| oldpool = conf->r1bio_pool; |
| conf->r1bio_pool = newpool; |
| |
| for (d = d2 = 0; d < conf->raid_disks; d++) { |
| struct md_rdev *rdev = conf->mirrors[d].rdev; |
| if (rdev && rdev->raid_disk != d2) { |
| sysfs_unlink_rdev(mddev, rdev); |
| rdev->raid_disk = d2; |
| sysfs_unlink_rdev(mddev, rdev); |
| if (sysfs_link_rdev(mddev, rdev)) |
| printk(KERN_WARNING |
| "md/raid1:%s: cannot register rd%d\n", |
| mdname(mddev), rdev->raid_disk); |
| } |
| 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; |
| |
| unfreeze_array(conf); |
| |
| set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); |
| set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
| md_wakeup_thread(mddev->thread); |
| |
| mempool_destroy(oldpool); |
| return 0; |
| } |
| |
| static void raid1_quiesce(struct mddev *mddev, int state) |
| { |
| struct r1conf *conf = mddev->private; |
| |
| switch(state) { |
| case 2: /* wake for suspend */ |
| wake_up(&conf->wait_barrier); |
| break; |
| case 1: |
| freeze_array(conf, 0); |
| break; |
| case 0: |
| unfreeze_array(conf); |
| break; |
| } |
| } |
| |
| static void *raid1_takeover(struct mddev *mddev) |
| { |
| /* raid1 can take over: |
| * raid5 with 2 devices, any layout or chunk size |
| */ |
| if (mddev->level == 5 && mddev->raid_disks == 2) { |
| struct r1conf *conf; |
| mddev->new_level = 1; |
| mddev->new_layout = 0; |
| mddev->new_chunk_sectors = 0; |
| conf = setup_conf(mddev); |
| if (!IS_ERR(conf)) |
| /* Array must appear to be quiesced */ |
| conf->array_frozen = 1; |
| return conf; |
| } |
| return ERR_PTR(-EINVAL); |
| } |
| |
| static struct md_personality raid1_personality = |
| { |
| .name = "raid1", |
| .level = 1, |
| .owner = THIS_MODULE, |
| .make_request = make_request, |
| .run = run, |
| .free = raid1_free, |
| .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, |
| .size = raid1_size, |
| .check_reshape = raid1_reshape, |
| .quiesce = raid1_quiesce, |
| .takeover = raid1_takeover, |
| .congested = raid1_congested, |
| }; |
| |
| 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_DESCRIPTION("RAID1 (mirroring) personality for MD"); |
| MODULE_ALIAS("md-personality-3"); /* RAID1 */ |
| MODULE_ALIAS("md-raid1"); |
| MODULE_ALIAS("md-level-1"); |
| |
| module_param(max_queued_requests, int, S_IRUGO|S_IWUSR); |