From f8c9e74ff0832f2244d7991d2aea13851b20a622 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 21 May 2012 09:28:33 +1000 Subject: [PATCH] md/raid10: Introduce 'prev' geometry to support reshape. When RAID10 supports reshape it will need a 'previous' and a 'current' geometry, so introduce that here. Use the 'prev' geometry when before the reshape_position, and the current 'geo' when beyond it. At other times, use both as appropriate. For now, both are identical (And reshape_position is never set). When we use the 'prev' geometry, we must use the old data_offset. When we use the current (And a reshape is happening) we must use the new_data_offset. Signed-off-by: NeilBrown --- drivers/md/raid10.c | 107 +++++++++++++++++++++++++++++++++++--------- drivers/md/raid10.h | 8 +++- 2 files changed, 92 insertions(+), 23 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 36f445f9e11d..1c90005ab343 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -504,15 +504,13 @@ static void raid10_end_write_request(struct bio *bio, int error) * sector offset to a virtual address */ -static void raid10_find_phys(struct r10conf *conf, struct r10bio *r10bio) +static void __raid10_find_phys(struct geom *geo, struct r10bio *r10bio) { int n,f; sector_t sector; sector_t chunk; sector_t stripe; int dev; - struct geom *geo = &conf->geo; - int slot = 0; /* now calculate first sector/dev */ @@ -550,12 +548,29 @@ static void raid10_find_phys(struct r10conf *conf, struct r10bio *r10bio) sector += (geo->chunk_mask + 1); } } - BUG_ON(slot != conf->copies); +} + +static void raid10_find_phys(struct r10conf *conf, struct r10bio *r10bio) +{ + struct geom *geo = &conf->geo; + + if (conf->reshape_progress != MaxSector && + ((r10bio->sector >= conf->reshape_progress) != + conf->mddev->reshape_backwards)) { + set_bit(R10BIO_Previous, &r10bio->state); + geo = &conf->prev; + } else + clear_bit(R10BIO_Previous, &r10bio->state); + + __raid10_find_phys(geo, r10bio); } static sector_t raid10_find_virt(struct r10conf *conf, sector_t sector, int dev) { sector_t offset, chunk, vchunk; + /* Never use conf->prev as this is only called during resync + * or recovery, so reshape isn't happening + */ struct geom *geo = &conf->geo; offset = sector & geo->chunk_mask; @@ -603,6 +618,11 @@ static int raid10_mergeable_bvec(struct request_queue *q, unsigned int bio_sectors = bvm->bi_size >> 9; struct geom *geo = &conf->geo; + if (conf->reshape_progress != MaxSector && + ((sector >= conf->reshape_progress) != + conf->mddev->reshape_backwards)) + geo = &conf->prev; + if (geo->near_copies < geo->raid_disks) { max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; @@ -617,6 +637,12 @@ static int raid10_mergeable_bvec(struct request_queue *q, if (mddev->merge_check_needed) { struct r10bio r10_bio; int s; + if (conf->reshape_progress != MaxSector) { + /* Cannot give any guidance during reshape */ + if (max <= biovec->bv_len && bio_sectors == 0) + return biovec->bv_len; + return 0; + } r10_bio.sector = sector; raid10_find_phys(conf, &r10_bio); rcu_read_lock(); @@ -816,7 +842,10 @@ static int raid10_congested(void *data, int bits) if (mddev_congested(mddev, bits)) return 1; rcu_read_lock(); - for (i = 0; i < conf->geo.raid_disks && ret == 0; i++) { + for (i = 0; + (i < conf->geo.raid_disks || i < conf->prev.raid_disks) + && ret == 0; + 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); @@ -977,13 +1006,23 @@ static void unfreeze_array(struct r10conf *conf) spin_unlock_irq(&conf->resync_lock); } +static sector_t choose_data_offset(struct r10bio *r10_bio, + struct md_rdev *rdev) +{ + if (!test_bit(MD_RECOVERY_RESHAPE, &rdev->mddev->recovery) || + test_bit(R10BIO_Previous, &r10_bio->state)) + return rdev->data_offset; + else + return rdev->new_data_offset; +} + static void make_request(struct mddev *mddev, struct bio * bio) { struct r10conf *conf = mddev->private; struct r10bio *r10_bio; struct bio *read_bio; int i; - sector_t chunk_mask = conf->geo.chunk_mask; + sector_t chunk_mask = (conf->geo.chunk_mask & conf->prev.chunk_mask); int chunk_sects = chunk_mask + 1; const int rw = bio_data_dir(bio); const unsigned long do_sync = (bio->bi_rw & REQ_SYNC); @@ -1004,7 +1043,8 @@ static void make_request(struct mddev *mddev, struct bio * bio) */ if (unlikely((bio->bi_sector & chunk_mask) + (bio->bi_size >> 9) > chunk_sects - && conf->geo.near_copies < conf->geo.raid_disks)) { + && (conf->geo.near_copies < conf->geo.raid_disks + || conf->prev.near_copies < conf->prev.raid_disks))) { struct bio_pair *bp; /* Sanity check -- queue functions should prevent this happening */ if (bio->bi_vcnt != 1 || @@ -1098,7 +1138,7 @@ read_again: r10_bio->devs[slot].rdev = rdev; read_bio->bi_sector = r10_bio->devs[slot].addr + - rdev->data_offset; + choose_data_offset(r10_bio, rdev); read_bio->bi_bdev = rdev->bdev; read_bio->bi_end_io = raid10_end_read_request; read_bio->bi_rw = READ | do_sync; @@ -1302,7 +1342,8 @@ retry_write: r10_bio->devs[i].bio = mbio; mbio->bi_sector = (r10_bio->devs[i].addr+ - conf->mirrors[d].rdev->data_offset); + choose_data_offset(r10_bio, + conf->mirrors[d].rdev)); mbio->bi_bdev = conf->mirrors[d].rdev->bdev; mbio->bi_end_io = raid10_end_write_request; mbio->bi_rw = WRITE | do_sync | do_fua; @@ -1326,8 +1367,10 @@ retry_write: * so it cannot disappear, so the replacement cannot * become NULL here */ - mbio->bi_sector = (r10_bio->devs[i].addr+ - conf->mirrors[d].replacement->data_offset); + mbio->bi_sector = (r10_bio->devs[i].addr + + choose_data_offset( + r10_bio, + conf->mirrors[d].replacement)); mbio->bi_bdev = conf->mirrors[d].replacement->bdev; mbio->bi_end_io = raid10_end_write_request; mbio->bi_rw = WRITE | do_sync | do_fua; @@ -1397,7 +1440,7 @@ static void status(struct seq_file *seq, struct mddev *mddev) * Don't consider the device numbered 'ignore' * as we might be about to remove it. */ -static int enough(struct r10conf *conf, int ignore) +static int _enough(struct r10conf *conf, struct geom *geo, int ignore) { int first = 0; @@ -1408,7 +1451,7 @@ static int enough(struct r10conf *conf, int ignore) if (conf->mirrors[first].rdev && first != ignore) cnt++; - first = (first+1) % conf->geo.raid_disks; + first = (first+1) % geo->raid_disks; } if (cnt == 0) return 0; @@ -1416,6 +1459,12 @@ static int enough(struct r10conf *conf, int ignore) return 1; } +static int enough(struct r10conf *conf, int ignore) +{ + return _enough(conf, &conf->geo, ignore) && + _enough(conf, &conf->prev, ignore); +} + static void error(struct mddev *mddev, struct md_rdev *rdev) { char b[BDEVNAME_SIZE]; @@ -1548,7 +1597,7 @@ static int raid10_add_disk(struct mddev *mddev, struct md_rdev *rdev) * very different from resync */ return -EBUSY; - if (rdev->saved_raid_disk < 0 && !enough(conf, -1)) + if (rdev->saved_raid_disk < 0 && !_enough(conf, &conf->prev, -1)) return -EINVAL; if (rdev->raid_disk >= 0) @@ -2223,7 +2272,9 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 " (%d sectors at %llu on %s)\n", mdname(mddev), s, (unsigned long long)( - sect + rdev->data_offset), + sect + + choose_data_offset(r10_bio, + rdev)), bdevname(rdev->bdev, b)); printk(KERN_NOTICE "md/raid10:%s: %s: failing " "drive\n", @@ -2261,7 +2312,8 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 " (%d sectors at %llu on %s)\n", mdname(mddev), s, (unsigned long long)( - sect + rdev->data_offset), + sect + + choose_data_offset(r10_bio, rdev)), bdevname(rdev->bdev, b)); printk(KERN_NOTICE "md/raid10:%s: %s: failing " "drive\n", @@ -2274,7 +2326,8 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 " (%d sectors at %llu on %s)\n", mdname(mddev), s, (unsigned long long)( - sect + rdev->data_offset), + sect + + choose_data_offset(r10_bio, rdev)), bdevname(rdev->bdev, b)); atomic_add(s, &rdev->corrected_errors); } @@ -2348,7 +2401,7 @@ static int narrow_write_error(struct r10bio *r10_bio, int i) wbio = bio_clone_mddev(bio, GFP_NOIO, mddev); md_trim_bio(wbio, sector - bio->bi_sector, sectors); wbio->bi_sector = (r10_bio->devs[i].addr+ - rdev->data_offset+ + choose_data_offset(r10_bio, rdev) + (sector - r10_bio->sector)); wbio->bi_bdev = rdev->bdev; if (submit_bio_wait(WRITE, wbio) == 0) @@ -2425,7 +2478,7 @@ read_more: r10_bio->devs[slot].bio = bio; r10_bio->devs[slot].rdev = rdev; bio->bi_sector = r10_bio->devs[slot].addr - + rdev->data_offset; + + choose_data_offset(r10_bio, rdev); bio->bi_bdev = rdev->bdev; bio->bi_rw = READ | do_sync; bio->bi_private = r10_bio; @@ -3254,6 +3307,8 @@ static struct r10conf *setup_conf(struct mddev *mddev) goto out; calc_sectors(conf, mddev->dev_sectors); + conf->prev = conf->geo; + conf->reshape_progress = MaxSector; spin_lock_init(&conf->device_lock); INIT_LIST_HEAD(&conf->retry_list); @@ -3319,8 +3374,10 @@ static int run(struct mddev *mddev) rdev_for_each(rdev, mddev) { disk_idx = rdev->raid_disk; - if (disk_idx >= conf->geo.raid_disks - || disk_idx < 0) + if (disk_idx < 0) + continue; + if (disk_idx >= conf->geo.raid_disks && + disk_idx >= conf->prev.raid_disks) continue; disk = conf->mirrors + disk_idx; @@ -3347,7 +3404,10 @@ static int run(struct mddev *mddev) } mddev->degraded = 0; - for (i = 0; i < conf->geo.raid_disks; i++) { + for (i = 0; + i < conf->geo.raid_disks + || i < conf->prev.raid_disks; + i++) { disk = conf->mirrors + i; @@ -3466,6 +3526,9 @@ static int raid10_resize(struct mddev *mddev, sector_t sectors) struct r10conf *conf = mddev->private; sector_t oldsize, size; + if (mddev->reshape_position != MaxSector) + return -EBUSY; + if (conf->geo.far_copies > 1 && !conf->geo.far_offset) return -EINVAL; diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h index 4c4942ac46fc..37509d7134aa 100644 --- a/drivers/md/raid10.h +++ b/drivers/md/raid10.h @@ -34,13 +34,14 @@ struct r10conf { */ int chunk_shift; /* shift from chunks to sectors */ sector_t chunk_mask; - } geo; + } prev, geo; int copies; /* near_copies * far_copies. * must be <= raid_disks */ sector_t dev_sectors; /* temp copy of * mddev->dev_sectors */ + sector_t reshape_progress; struct list_head retry_list; /* queue pending writes and submit them on unplug */ @@ -147,5 +148,10 @@ enum r10bio_state { */ R10BIO_MadeGood, R10BIO_WriteError, +/* During a reshape we might be performing IO on the + * 'previous' part of the array, in which case this + * flag is set + */ + R10BIO_Previous, }; #endif -- 2.39.2