From a68e58703575b9c03d610a818e0241564fc17f68 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 11 May 2011 14:40:44 +1000 Subject: [PATCH] md/raid1: split out two sub-functions from sync_request_write sync_request_write is too big and too deep. So split out two self-contains bits of functionality into separate function. Signed-off-by: NeilBrown --- drivers/md/raid1.c | 365 ++++++++++++++++++++++++--------------------- 1 file changed, 192 insertions(+), 173 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index f0b0c79b3899..7fd7a4d6f5c7 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1181,194 +1181,213 @@ 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; + struct bio *bio = r1_bio->bios[r1_bio->read_disk]; + sector_t sect = r1_bio->sector; + int sectors = r1_bio->sectors; + int idx = 0; - bio = r1_bio->bios[r1_bio->read_disk]; - - - if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { - /* We have read all readable devices. If we haven't - * got the block, then there is no hope left. - * If we have, then we want to do a comparison - * and skip the write if everything is the same. - * If any blocks failed to read, then we need to - * attempt an over-write - */ - int primary; - if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { - for (i=0; iraid_disks; i++) - if (r1_bio->bios[i]->bi_end_io == end_sync_read) - md_error(mddev, conf->mirrors[i].rdev); + while(sectors) { + int s = sectors; + int d = r1_bio->read_disk; + int success = 0; + mdk_rdev_t *rdev; - md_done_sync(mddev, r1_bio->sectors, 1); + 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; + return 0; } - for (primary=0; primaryraid_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; + sectors -= s; + sect += s; + idx ++; + } + 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; + + if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { for (i=0; iraid_disks; i++) - if (r1_bio->bios[i]->bi_end_io == end_sync_read) { - int j; - int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9); - struct bio *pbio = r1_bio->bios[primary]; - struct bio *sbio = r1_bio->bios[i]; - - if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { - for (j = vcnt; j-- ; ) { - struct page *p, *s; - p = pbio->bi_io_vec[j].bv_page; - s = sbio->bi_io_vec[j].bv_page; - if (memcmp(page_address(p), - page_address(s), - PAGE_SIZE)) - break; - } - } else - j = 0; - if (j >= 0) - mddev->resync_mismatches += r1_bio->sectors; - if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) - && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { - sbio->bi_end_io = NULL; - rdev_dec_pending(conf->mirrors[i].rdev, mddev); - } else { - /* fixup the bio for reuse */ - int size; - sbio->bi_vcnt = vcnt; - sbio->bi_size = r1_bio->sectors << 9; - sbio->bi_idx = 0; - sbio->bi_phys_segments = 0; - sbio->bi_flags &= ~(BIO_POOL_MASK - 1); - sbio->bi_flags |= 1 << BIO_UPTODATE; - sbio->bi_next = NULL; - sbio->bi_sector = r1_bio->sector + - conf->mirrors[i].rdev->data_offset; - sbio->bi_bdev = conf->mirrors[i].rdev->bdev; - size = sbio->bi_size; - for (j = 0; j < vcnt ; j++) { - struct bio_vec *bi; - bi = &sbio->bi_io_vec[j]; - bi->bv_offset = 0; - if (size > PAGE_SIZE) - bi->bv_len = PAGE_SIZE; - else - bi->bv_len = size; - size -= PAGE_SIZE; - memcpy(page_address(bi->bv_page), - page_address(pbio->bi_io_vec[j].bv_page), - PAGE_SIZE); - } + if (r1_bio->bios[i]->bi_end_io == end_sync_read) + md_error(mddev, conf->mirrors[i].rdev); - } - } + md_done_sync(mddev, r1_bio->sectors, 1); + put_buf(r1_bio); + return -1; } - 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; + for (primary=0; primaryraid_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; iraid_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; - } - } - 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 + 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 { - 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; + /* 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); + } + } - sectors -= s; - sect += s; - idx ++; } - } + 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(MD_RECOVERY_REQUESTED, &mddev->recovery)) + if (process_checks(r1_bio) < 0) + return; + + if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) + /* ouch - failed to read all of that. */ + if (!fix_sync_read_error(r1_bio)) + return; /* * schedule writes */ -- 2.20.1