diff options
Diffstat (limited to 'drivers/md/raid1.c')
| -rw-r--r-- | drivers/md/raid1.c | 267 |
1 files changed, 139 insertions, 128 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index a1f3fbed9100..14422407e520 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1066,17 +1066,107 @@ static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule) kfree(plug); } -static void raid1_make_request(struct mddev *mddev, struct bio * bio) +static void raid1_read_request(struct mddev *mddev, struct bio *bio, + struct r1bio *r1_bio) { struct r1conf *conf = mddev->private; struct raid1_info *mirror; - struct r1bio *r1_bio; struct bio *read_bio; + struct bitmap *bitmap = mddev->bitmap; + const int op = bio_op(bio); + const unsigned long do_sync = (bio->bi_opf & REQ_SYNC); + int sectors_handled; + int max_sectors; + int rdisk; + + wait_barrier(conf, bio); + +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' + */ + raid1_log(mddev, "wait behind writes"); + 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; + bio_set_op_attrs(read_bio, op, do_sync); + if (test_bit(FailFast, &mirror->rdev->flags) && + test_bit(R1BIO_FailFast, &r1_bio->state)) + read_bio->bi_opf |= MD_FAILFAST; + read_bio->bi_private = r1_bio; + + if (mddev->gendisk) + trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev), + read_bio, disk_devt(mddev->gendisk), + r1_bio->sector); + + 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); +} + +static void raid1_write_request(struct mddev *mddev, struct bio *bio, + struct r1bio *r1_bio) +{ + struct r1conf *conf = mddev->private; int i, disks; - struct bitmap *bitmap; + struct bitmap *bitmap = mddev->bitmap; unsigned long flags; const int op = bio_op(bio); - const int rw = bio_data_dir(bio); const unsigned long do_sync = (bio->bi_opf & REQ_SYNC); const unsigned long do_flush_fua = (bio->bi_opf & (REQ_PREFLUSH | REQ_FUA)); @@ -1096,15 +1186,15 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio) md_write_start(mddev, bio); /* wait on superblock update early */ - if (bio_data_dir(bio) == WRITE && - ((bio_end_sector(bio) > mddev->suspend_lo && + 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))))) { - /* As the suspend_* range is controlled by - * userspace, we want an interruptible - * wait. + 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 (;;) { @@ -1115,128 +1205,15 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio) 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)))) + bio->bi_iter.bi_sector, + bio_end_sector(bio)))) break; schedule(); } finish_wait(&conf->wait_barrier, &w); } - start_next_window = wait_barrier(conf, bio); - bitmap = mddev->bitmap; - - /* - * make_request() can abort the operation when read-ahead 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' - */ - raid1_log(mddev, "wait behind writes"); - 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; - bio_set_op_attrs(read_bio, op, do_sync); - if (test_bit(FailFast, &mirror->rdev->flags) && - test_bit(R1BIO_FailFast, &r1_bio->state)) - read_bio->bi_opf |= MD_FAILFAST; - read_bio->bi_private = r1_bio; - - if (mddev->gendisk) - trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev), - read_bio, disk_devt(mddev->gendisk), - r1_bio->sector); - - 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); raid1_log(mddev, "wait queued"); @@ -1280,8 +1257,7 @@ read_again: int bad_sectors; int is_bad; - is_bad = is_badblock(rdev, r1_bio->sector, - max_sectors, + 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 @@ -1370,7 +1346,8 @@ read_again: continue; mbio = bio_clone_mddev(bio, GFP_NOIO, mddev); - bio_trim(mbio, r1_bio->sector - bio->bi_iter.bi_sector, max_sectors); + bio_trim(mbio, r1_bio->sector - bio->bi_iter.bi_sector, + max_sectors); if (first_clone) { /* do behind I/O ? @@ -1464,6 +1441,40 @@ read_again: wake_up(&conf->wait_barrier); } +static void raid1_make_request(struct mddev *mddev, struct bio *bio) +{ + struct r1conf *conf = mddev->private; + struct r1bio *r1_bio; + + /* + * make_request() can abort the operation when read-ahead 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 (bio_data_dir(bio) == READ) + raid1_read_request(mddev, bio, r1_bio); + else + raid1_write_request(mddev, bio, r1_bio); +} + static void raid1_status(struct seq_file *seq, struct mddev *mddev) { struct r1conf *conf = mddev->private; |
