diff options
Diffstat (limited to 'drivers/md/raid1.c')
-rw-r--r-- | drivers/md/raid1.c | 506 |
1 files changed, 252 insertions, 254 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 2b7a7ff401d..5d096096f95 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -297,23 +297,24 @@ static void raid1_end_read_request(struct bio *bio, int error) rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); } -static void r1_bio_write_done(r1bio_t *r1_bio, int vcnt, struct bio_vec *bv, - int behind) +static void r1_bio_write_done(r1bio_t *r1_bio) { if (atomic_dec_and_test(&r1_bio->remaining)) { /* 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 = vcnt; + int i = r1_bio->behind_page_count; while (i--) - safe_put_page(bv[i].bv_page); + safe_put_page(r1_bio->behind_pages[i]); + kfree(r1_bio->behind_pages); + r1_bio->behind_pages = 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), - behind); + test_bit(R1BIO_BehindIO, &r1_bio->state)); md_write_end(r1_bio->mddev); raid_end_bio_io(r1_bio); } @@ -386,7 +387,7 @@ static void raid1_end_write_request(struct bio *bio, int error) * Let's see if all mirrored write operations have finished * already. */ - r1_bio_write_done(r1_bio, bio->bi_vcnt, bio->bi_io_vec, behind); + r1_bio_write_done(r1_bio); if (to_put) bio_put(to_put); @@ -411,10 +412,10 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) { const sector_t this_sector = r1_bio->sector; const int sectors = r1_bio->sectors; - int new_disk = -1; int start_disk; + int best_disk; int i; - sector_t new_distance, current_distance; + sector_t best_dist; mdk_rdev_t *rdev; int choose_first; @@ -425,6 +426,8 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) * We take the first readable disk when above the resync window. */ retry: + best_disk = -1; + best_dist = MaxSector; if (conf->mddev->recovery_cp < MaxSector && (this_sector + sectors >= conf->next_resync)) { choose_first = 1; @@ -434,8 +437,8 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) start_disk = conf->last_used; } - /* make sure the disk is operational */ for (i = 0 ; i < conf->raid_disks ; i++) { + sector_t dist; int disk = start_disk + i; if (disk >= conf->raid_disks) disk -= conf->raid_disks; @@ -443,60 +446,43 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) rdev = rcu_dereference(conf->mirrors[disk].rdev); if (r1_bio->bios[disk] == IO_BLOCKED || rdev == NULL - || !test_bit(In_sync, &rdev->flags)) + || test_bit(Faulty, &rdev->flags)) continue; - - new_disk = disk; - if (!test_bit(WriteMostly, &rdev->flags)) - break; - } - - if (new_disk < 0 || choose_first) - goto rb_out; - - /* - * Don't change to another disk for sequential reads: - */ - if (conf->next_seq_sect == this_sector) - goto rb_out; - if (this_sector == conf->mirrors[new_disk].head_position) - goto rb_out; - - current_distance = abs(this_sector - - conf->mirrors[new_disk].head_position); - - /* look for a better disk - i.e. head is closer */ - start_disk = new_disk; - for (i = 1; i < conf->raid_disks; i++) { - int disk = start_disk + 1; - if (disk >= conf->raid_disks) - disk -= conf->raid_disks; - - rdev = rcu_dereference(conf->mirrors[disk].rdev); - if (r1_bio->bios[disk] == IO_BLOCKED - || rdev == NULL - || !test_bit(In_sync, &rdev->flags) - || test_bit(WriteMostly, &rdev->flags)) + if (!test_bit(In_sync, &rdev->flags) && + rdev->recovery_offset < this_sector + sectors) continue; - - if (!atomic_read(&rdev->nr_pending)) { - new_disk = disk; + if (test_bit(WriteMostly, &rdev->flags)) { + /* Don't balance among write-mostly, just + * use the first as a last resort */ + if (best_disk < 0) + best_disk = disk; + continue; + } + /* This is a reasonable device to use. It might + * even be best. + */ + dist = abs(this_sector - conf->mirrors[disk].head_position); + if (choose_first + /* Don't change to another disk for sequential reads */ + || conf->next_seq_sect == this_sector + || dist == 0 + /* If device is idle, use it */ + || atomic_read(&rdev->nr_pending) == 0) { + best_disk = disk; break; } - new_distance = abs(this_sector - conf->mirrors[disk].head_position); - if (new_distance < current_distance) { - current_distance = new_distance; - new_disk = disk; + if (dist < best_dist) { + best_dist = dist; + best_disk = disk; } } - rb_out: - if (new_disk >= 0) { - rdev = rcu_dereference(conf->mirrors[new_disk].rdev); + if (best_disk >= 0) { + rdev = rcu_dereference(conf->mirrors[best_disk].rdev); if (!rdev) goto retry; atomic_inc(&rdev->nr_pending); - if (!test_bit(In_sync, &rdev->flags)) { + if (test_bit(Faulty, &rdev->flags)) { /* cannot risk returning a device that failed * before we inc'ed nr_pending */ @@ -504,11 +490,11 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) goto retry; } conf->next_seq_sect = this_sector + sectors; - conf->last_used = new_disk; + conf->last_used = best_disk; } rcu_read_unlock(); - return new_disk; + return best_disk; } static int raid1_congested(void *data, int bits) @@ -675,37 +661,36 @@ static void unfreeze_array(conf_t *conf) /* duplicate the data pages for behind I/O - * We return a list of bio_vec rather than just page pointers - * as it makes freeing easier */ -static struct bio_vec *alloc_behind_pages(struct bio *bio) +static void alloc_behind_pages(struct bio *bio, r1bio_t *r1_bio) { int i; struct bio_vec *bvec; - struct bio_vec *pages = kzalloc(bio->bi_vcnt * sizeof(struct bio_vec), + struct page **pages = kzalloc(bio->bi_vcnt * sizeof(struct page*), GFP_NOIO); if (unlikely(!pages)) - goto do_sync_io; + return; bio_for_each_segment(bvec, bio, i) { - pages[i].bv_page = alloc_page(GFP_NOIO); - if (unlikely(!pages[i].bv_page)) + pages[i] = alloc_page(GFP_NOIO); + if (unlikely(!pages[i])) goto do_sync_io; - memcpy(kmap(pages[i].bv_page) + bvec->bv_offset, + memcpy(kmap(pages[i]) + bvec->bv_offset, kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len); - kunmap(pages[i].bv_page); + kunmap(pages[i]); kunmap(bvec->bv_page); } - - return pages; + r1_bio->behind_pages = pages; + r1_bio->behind_page_count = bio->bi_vcnt; + set_bit(R1BIO_BehindIO, &r1_bio->state); + return; do_sync_io: - if (pages) - for (i = 0; i < bio->bi_vcnt && pages[i].bv_page; i++) - put_page(pages[i].bv_page); + for (i = 0; i < bio->bi_vcnt; i++) + if (pages[i]) + put_page(pages[i]); kfree(pages); PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size); - return NULL; } static int make_request(mddev_t *mddev, struct bio * bio) @@ -717,7 +702,6 @@ static int make_request(mddev_t *mddev, struct bio * bio) int i, targets = 0, disks; struct bitmap *bitmap; unsigned long flags; - struct bio_vec *behind_pages = NULL; 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)); @@ -870,9 +854,8 @@ static int make_request(mddev_t *mddev, struct bio * bio) if (bitmap && (atomic_read(&bitmap->behind_writes) < mddev->bitmap_info.max_write_behind) && - !waitqueue_active(&bitmap->behind_wait) && - (behind_pages = alloc_behind_pages(bio)) != NULL) - set_bit(R1BIO_BehindIO, &r1_bio->state); + !waitqueue_active(&bitmap->behind_wait)) + alloc_behind_pages(bio, r1_bio); atomic_set(&r1_bio->remaining, 1); atomic_set(&r1_bio->behind_remaining, 0); @@ -893,7 +876,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) mbio->bi_rw = WRITE | do_flush_fua | do_sync; mbio->bi_private = r1_bio; - if (behind_pages) { + if (r1_bio->behind_pages) { struct bio_vec *bvec; int j; @@ -905,7 +888,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) * them all */ __bio_for_each_segment(bvec, mbio, j, 0) - bvec->bv_page = behind_pages[j].bv_page; + bvec->bv_page = r1_bio->behind_pages[j]; if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags)) atomic_inc(&r1_bio->behind_remaining); } @@ -915,8 +898,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) bio_list_add(&conf->pending_bio_list, mbio); spin_unlock_irqrestore(&conf->device_lock, flags); } - r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL); - kfree(behind_pages); /* the behind pages are attached to the bios now */ + r1_bio_write_done(r1_bio); /* In case raid1d snuck in to freeze_array */ wake_up(&conf->wait_barrier); @@ -1196,194 +1178,210 @@ static void end_sync_write(struct bio *bio, int error) } } -static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) +static int fix_sync_read_error(r1bio_t *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. + */ + mddev_t *mddev = r1_bio->mddev; conf_t *conf = mddev->private; - int i; - int disks = conf->raid_disks; - struct bio *bio, *wbio; - - bio = r1_bio->bios[r1_bio->read_disk]; + 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; + mdk_rdev_t *rdev; + int start; - if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { - /* We have read all readable devices. If we haven't - * got the block, then there is no hope left. - * If we have, then we want to do a comparison - * and skip the write if everything is the same. - * If any blocks failed to read, then we need to - * attempt an over-write - */ - int primary; - if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { - for (i=0; i<mddev->raid_disks; i++) - if (r1_bio->bios[i]->bi_end_io == end_sync_read) - md_error(mddev, conf->mirrors[i].rdev); + 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) + d = 0; + } while (!success && d != r1_bio->read_disk); - md_done_sync(mddev, r1_bio->sectors, 1); + if (!success) { + char b[BDEVNAME_SIZE]; + /* Cannot read from anywhere, array is toast */ + md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); + 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); + md_done_sync(mddev, r1_bio->sectors, 0); put_buf(r1_bio); - return; + return 0; } - for (primary=0; primary<mddev->raid_disks; primary++) - if (r1_bio->bios[primary]->bi_end_io == end_sync_read && - test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) { - r1_bio->bios[primary]->bi_end_io = NULL; - rdev_dec_pending(conf->mirrors[primary].rdev, mddev); - break; - } - r1_bio->read_disk = primary; - for (i=0; i<mddev->raid_disks; i++) - if (r1_bio->bios[i]->bi_end_io == end_sync_read) { - int j; - int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9); - struct bio *pbio = r1_bio->bios[primary]; - struct bio *sbio = r1_bio->bios[i]; - - if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { - for (j = vcnt; j-- ; ) { - struct page *p, *s; - p = pbio->bi_io_vec[j].bv_page; - s = sbio->bi_io_vec[j].bv_page; - if (memcmp(page_address(p), - page_address(s), - PAGE_SIZE)) - break; - } - } else - j = 0; - if (j >= 0) - mddev->resync_mismatches += r1_bio->sectors; - if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) - && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { - sbio->bi_end_io = NULL; - rdev_dec_pending(conf->mirrors[i].rdev, mddev); - } else { - /* fixup the bio for reuse */ - int size; - sbio->bi_vcnt = vcnt; - sbio->bi_size = r1_bio->sectors << 9; - sbio->bi_idx = 0; - sbio->bi_phys_segments = 0; - sbio->bi_flags &= ~(BIO_POOL_MASK - 1); - sbio->bi_flags |= 1 << BIO_UPTODATE; - sbio->bi_next = NULL; - sbio->bi_sector = r1_bio->sector + - conf->mirrors[i].rdev->data_offset; - sbio->bi_bdev = conf->mirrors[i].rdev->bdev; - size = sbio->bi_size; - for (j = 0; j < vcnt ; j++) { - struct bio_vec *bi; - bi = &sbio->bi_io_vec[j]; - bi->bv_offset = 0; - if (size > PAGE_SIZE) - bi->bv_len = PAGE_SIZE; - else - bi->bv_len = size; - size -= PAGE_SIZE; - memcpy(page_address(bi->bv_page), - page_address(pbio->bi_io_vec[j].bv_page), - PAGE_SIZE); - } - } - } + start = d; + /* write it back and re-read */ + while (d != r1_bio->read_disk) { + if (d == 0) + d = conf->raid_disks; + d--; + if (r1_bio->bios[d]->bi_end_io != end_sync_read) + continue; + rdev = conf->mirrors[d].rdev; + if (sync_page_io(rdev, + sect, + s<<9, + bio->bi_io_vec[idx].bv_page, + WRITE, false) == 0) { + r1_bio->bios[d]->bi_end_io = NULL; + rdev_dec_pending(rdev, mddev); + md_error(mddev, rdev); + } else + atomic_add(s, &rdev->corrected_errors); + } + d = start; + while (d != r1_bio->read_disk) { + if (d == 0) + d = conf->raid_disks; + d--; + if (r1_bio->bios[d]->bi_end_io != end_sync_read) + continue; + rdev = conf->mirrors[d].rdev; + if (sync_page_io(rdev, + sect, + s<<9, + bio->bi_io_vec[idx].bv_page, + READ, false) == 0) + md_error(mddev, rdev); + } + sectors -= s; + sect += s; + idx ++; } - if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { - /* ouch - failed to read all of that. - * Try some synchronous reads of other devices to get - * good data, much like with normal read errors. Only - * read into the pages we already have so we don't - * need to re-issue the read request. - * We don't need to freeze the array, because being in an - * active sync request, there is no normal IO, and - * no overlapping syncs. - */ - sector_t sect = r1_bio->sector; - int sectors = r1_bio->sectors; - int idx = 0; - - while(sectors) { - int s = sectors; - int d = r1_bio->read_disk; - int success = 0; - mdk_rdev_t *rdev; - - if (s > (PAGE_SIZE>>9)) - s = PAGE_SIZE >> 9; - do { - if (r1_bio->bios[d]->bi_end_io == end_sync_read) { - /* No rcu protection needed here devices - * can only be removed when no resync is - * active, and resync is currently active - */ - rdev = conf->mirrors[d].rdev; - if (sync_page_io(rdev, - sect, - s<<9, - bio->bi_io_vec[idx].bv_page, - READ, false)) { - success = 1; - break; - } - } - d++; - if (d == conf->raid_disks) - d = 0; - } while (!success && d != r1_bio->read_disk); - - if (success) { - int start = d; - /* write it back and re-read */ - set_bit(R1BIO_Uptodate, &r1_bio->state); - while (d != r1_bio->read_disk) { - if (d == 0) - d = conf->raid_disks; - d--; - if (r1_bio->bios[d]->bi_end_io != end_sync_read) - continue; - rdev = conf->mirrors[d].rdev; - atomic_add(s, &rdev->corrected_errors); - if (sync_page_io(rdev, - sect, - s<<9, - bio->bi_io_vec[idx].bv_page, - WRITE, false) == 0) - md_error(mddev, rdev); - } - d = start; - while (d != r1_bio->read_disk) { - if (d == 0) - d = conf->raid_disks; - d--; - if (r1_bio->bios[d]->bi_end_io != end_sync_read) - continue; - rdev = conf->mirrors[d].rdev; - if (sync_page_io(rdev, - sect, - s<<9, - bio->bi_io_vec[idx].bv_page, - READ, false) == 0) - md_error(mddev, rdev); - } - } else { - char b[BDEVNAME_SIZE]; - /* Cannot read from anywhere, array is toast */ - md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); - printk(KERN_ALERT "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); - md_done_sync(mddev, r1_bio->sectors, 0); - put_buf(r1_bio); - return; + set_bit(R1BIO_Uptodate, &r1_bio->state); + set_bit(BIO_UPTODATE, &bio->bi_flags); + return 1; +} + +static int process_checks(r1bio_t *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 + */ + mddev_t *mddev = r1_bio->mddev; + conf_t *conf = mddev->private; + int primary; + int i; + + for (primary = 0; primary < conf->raid_disks; primary++) + if (r1_bio->bios[primary]->bi_end_io == end_sync_read && + test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) { + r1_bio->bios[primary]->bi_end_io = NULL; + rdev_dec_pending(conf->mirrors[primary].rdev, mddev); + break; + } + r1_bio->read_disk = primary; + for (i = 0; i < conf->raid_disks; i++) { + int j; + int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9); + struct bio *pbio = r1_bio->bios[primary]; + struct bio *sbio = r1_bio->bios[i]; + int size; + + if (r1_bio->bios[i]->bi_end_io != end_sync_read) + continue; + + if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { + for (j = vcnt; j-- ; ) { + struct page *p, *s; + p = pbio->bi_io_vec[j].bv_page; + s = sbio->bi_io_vec[j].bv_page; + if (memcmp(page_address(p), + page_address(s), + PAGE_SIZE)) + break; } - sectors -= s; - sect += s; - idx ++; + } else + j = 0; + if (j >= 0) + mddev->resync_mismatches += r1_bio->sectors; + if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) + && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { + /* No need to write to this device. */ + sbio->bi_end_io = NULL; + rdev_dec_pending(conf->mirrors[i].rdev, mddev); + continue; + } + /* fixup the bio for reuse */ + sbio->bi_vcnt = vcnt; + sbio->bi_size = r1_bio->sectors << 9; + sbio->bi_idx = 0; + sbio->bi_phys_segments = 0; + sbio->bi_flags &= ~(BIO_POOL_MASK - 1); + sbio->bi_flags |= 1 << BIO_UPTODATE; + sbio->bi_next = NULL; + sbio->bi_sector = r1_bio->sector + + conf->mirrors[i].rdev->data_offset; + sbio->bi_bdev = conf->mirrors[i].rdev->bdev; + size = sbio->bi_size; + for (j = 0; j < vcnt ; j++) { + struct bio_vec *bi; + bi = &sbio->bi_io_vec[j]; + bi->bv_offset = 0; + if (size > PAGE_SIZE) + bi->bv_len = PAGE_SIZE; + else + bi->bv_len = size; + size -= PAGE_SIZE; + memcpy(page_address(bi->bv_page), + page_address(pbio->bi_io_vec[j].bv_page), + PAGE_SIZE); } } + return 0; +} +static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) +{ + conf_t *conf = mddev->private; + int i; + int disks = conf->raid_disks; + 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)) + if (process_checks(r1_bio) < 0) + return; /* * schedule writes */ @@ -2063,7 +2061,7 @@ static int raid1_resize(mddev_t *mddev, sector_t sectors) set_capacity(mddev->gendisk, mddev->array_sectors); revalidate_disk(mddev->gendisk); if (sectors > mddev->dev_sectors && - mddev->recovery_cp == MaxSector) { + mddev->recovery_cp > mddev->dev_sectors) { mddev->recovery_cp = mddev->dev_sectors; set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); } |