Fixups are already sync for csum failures, this patch makes them sync for EIO case as well.
Fixups are now sharing pages with the parent sbio - instead of allocating a separate page to do a fixup we grab the page from the sbio buffer. Fixup bios are no longer reused. struct fixup is no longer needed, instead pass [sbio pointer, index]. Originally this was added to look at the possibility of sharing the code between drive swap and scrub, but it actually fixes a serious bug in scrub code where errors that could be corrected were ignored and reported as uncorrectable. Signed-off-by: Ilya Dryomov <[email protected]> --- fs/btrfs/scrub.c | 241 +++++++++++++++--------------------------------------- 1 files changed, 67 insertions(+), 174 deletions(-) diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 7c5eb21..e862167 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -60,7 +60,6 @@ typedef struct work_struct scrub_work_t; struct scrub_bio; struct scrub_page; struct scrub_dev; -struct scrub_fixup; static void scrub_bio_end_io(struct bio *bio, int err); static void scrub_checksum(scrub_work_t *work); static int scrub_checksum_data(struct scrub_dev *sdev, @@ -69,9 +68,11 @@ static int scrub_checksum_tree_block(struct scrub_dev *sdev, struct scrub_page *spag, u64 logical, void *buffer); static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer); -static void scrub_recheck_end_io(struct bio *bio, int err); -static void scrub_fixup_worker(scrub_work_t *work); -static void scrub_fixup(struct scrub_fixup *fixup); +static int scrub_fixup_check(struct scrub_bio *sbio, int ix); +static void scrub_fixup_end_io(struct bio *bio, int err); +static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector, + struct page *page); +static void scrub_fixup(struct scrub_bio *sbio, int ix); #define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */ #define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */ @@ -115,17 +116,6 @@ struct scrub_dev { spinlock_t stat_lock; }; -struct scrub_fixup { - struct scrub_dev *sdev; - struct bio *bio; - u64 logical; - u64 physical; - struct scrub_page spag; - scrub_work_t work; - int err; - int recheck; -}; - static void scrub_free_csums(struct scrub_dev *sdev) { while(!list_empty(&sdev->csum_list)) { @@ -250,108 +240,34 @@ nomem: */ static void scrub_recheck_error(struct scrub_bio *sbio, int ix) { - struct scrub_dev *sdev = sbio->sdev; - struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; - struct bio *bio = NULL; - struct page *page = NULL; - struct scrub_fixup *fixup = NULL; - int ret; - - /* - * while we're in here we do not want the transaction to commit. - * To prevent it, we increment scrubs_running. scrub_pause will - * have to wait until we're finished - * we can safely increment scrubs_running here, because we're - * in the context of the original bio which is still marked in_flight - */ - atomic_inc(&fs_info->scrubs_running); - - fixup = kzalloc(sizeof(*fixup), GFP_NOFS); - if (!fixup) - goto malloc_error; - - fixup->logical = sbio->logical + ix * PAGE_SIZE; - fixup->physical = sbio->physical + ix * PAGE_SIZE; - fixup->spag = sbio->spag[ix]; - fixup->sdev = sdev; - - bio = bio_alloc(GFP_NOFS, 1); - if (!bio) - goto malloc_error; - bio->bi_private = fixup; - bio->bi_size = 0; - bio->bi_bdev = sdev->dev->bdev; - fixup->bio = bio; - fixup->recheck = 0; - - page = alloc_page(GFP_NOFS); - if (!page) - goto malloc_error; - - ret = bio_add_page(bio, page, PAGE_SIZE, 0); - if (!ret) - goto malloc_error; - - if (!sbio->err) { - /* - * shorter path: just a checksum error, go ahead and correct it - */ - scrub_fixup_worker(&fixup->work); - return; + if (sbio->err) { + if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, + (sbio->physical + ix * PAGE_SIZE) >> 9, + sbio->bio->bi_io_vec[ix].bv_page) == 0) { + if (scrub_fixup_check(sbio, ix) == 0) + return; + } } - /* - * an I/O-error occured for one of the blocks in the bio, not - * necessarily for this one, so first try to read it separately - */ - SCRUB_INIT_WORK(&fixup->work, scrub_fixup_worker); - fixup->recheck = 1; - bio->bi_end_io = scrub_recheck_end_io; - bio->bi_sector = fixup->physical >> 9; - bio->bi_bdev = sdev->dev->bdev; - submit_bio(0, bio); - - return; - -malloc_error: - if (bio) - bio_put(bio); - if (page) - __free_page(page); - if (fixup) - kfree(fixup); - spin_lock(&sdev->stat_lock); - ++sdev->stat.malloc_errors; - spin_unlock(&sdev->stat_lock); - atomic_dec(&fs_info->scrubs_running); - wake_up(&fs_info->scrub_pause_wait); -} - -static void scrub_recheck_end_io(struct bio *bio, int err) -{ - struct scrub_fixup *fixup = bio->bi_private; - struct btrfs_fs_info *fs_info = fixup->sdev->dev->dev_root->fs_info; - - fixup->err = err; - SCRUB_QUEUE_WORK(fs_info->scrub_workers, &fixup->work); + scrub_fixup(sbio, ix); } -static int scrub_fixup_check(struct scrub_fixup *fixup) +static int scrub_fixup_check(struct scrub_bio *sbio, int ix) { int ret = 1; struct page *page; void *buffer; - u64 flags = fixup->spag.flags; + u64 flags = sbio->spag[ix].flags; - page = fixup->bio->bi_io_vec[0].bv_page; + page = sbio->bio->bi_io_vec[ix].bv_page; buffer = kmap_atomic(page, KM_USER0); if (flags & BTRFS_EXTENT_FLAG_DATA) { - ret = scrub_checksum_data(fixup->sdev, - &fixup->spag, buffer); + ret = scrub_checksum_data(sbio->sdev, + sbio->spag + ix, buffer); } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { - ret = scrub_checksum_tree_block(fixup->sdev, - &fixup->spag, - fixup->logical, + ret = scrub_checksum_tree_block(sbio->sdev, + sbio->spag + ix, + sbio->logical + ix * PAGE_SIZE, buffer); } else { WARN_ON(1); @@ -361,51 +277,25 @@ static int scrub_fixup_check(struct scrub_fixup *fixup) return ret; } -static void scrub_fixup_worker(scrub_work_t *work) -{ - struct scrub_fixup *fixup; - struct btrfs_fs_info *fs_info; - u64 flags; - int ret = 1; - - fixup = container_of(work, struct scrub_fixup, work); - fs_info = fixup->sdev->dev->dev_root->fs_info; - flags = fixup->spag.flags; - - if (fixup->recheck && fixup->err == 0) - ret = scrub_fixup_check(fixup); - - if (ret || fixup->err) - scrub_fixup(fixup); - - __free_page(fixup->bio->bi_io_vec[0].bv_page); - bio_put(fixup->bio); - - atomic_dec(&fs_info->scrubs_running); - wake_up(&fs_info->scrub_pause_wait); - - kfree(fixup); -} - static void scrub_fixup_end_io(struct bio *bio, int err) { complete((struct completion *)bio->bi_private); } -static void scrub_fixup(struct scrub_fixup *fixup) +static void scrub_fixup(struct scrub_bio *sbio, int ix) { - struct scrub_dev *sdev = fixup->sdev; + struct scrub_dev *sdev = sbio->sdev; struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; struct btrfs_multi_bio *multi = NULL; - struct bio *bio = fixup->bio; + u64 logical = sbio->logical + ix * PAGE_SIZE; u64 length; int i; int ret; DECLARE_COMPLETION_ONSTACK(complete); - if ((fixup->spag.flags & BTRFS_EXTENT_FLAG_DATA) && - (fixup->spag.have_csum == 0)) { + if ((sbio->spag[ix].flags & BTRFS_EXTENT_FLAG_DATA) && + (sbio->spag[ix].have_csum == 0)) { /* * nodatasum, don't try to fix anything * FIXME: we can do better, open the inode and trigger a @@ -415,71 +305,49 @@ static void scrub_fixup(struct scrub_fixup *fixup) } length = PAGE_SIZE; - ret = btrfs_map_block(map_tree, REQ_WRITE, fixup->logical, &length, + ret = btrfs_map_block(map_tree, REQ_WRITE, logical, &length, &multi, 0); if (ret || !multi || length < PAGE_SIZE) { printk(KERN_ERR "scrub_fixup: btrfs_map_block failed us for %llu\n", - (unsigned long long)fixup->logical); + (unsigned long long)logical); WARN_ON(1); return; } - if (multi->num_stripes == 1) { + if (multi->num_stripes == 1) /* there aren't any replicas */ goto uncorrectable; - } /* * first find a good copy */ for (i = 0; i < multi->num_stripes; ++i) { - if (i == fixup->spag.mirror_num) + if (i == sbio->spag[ix].mirror_num) continue; - bio->bi_sector = multi->stripes[i].physical >> 9; - bio->bi_bdev = multi->stripes[i].dev->bdev; - bio->bi_size = PAGE_SIZE; - bio->bi_next = NULL; - bio->bi_flags |= 1 << BIO_UPTODATE; - bio->bi_comp_cpu = -1; - bio->bi_end_io = scrub_fixup_end_io; - bio->bi_private = &complete; - - submit_bio(0, bio); - - wait_for_completion(&complete); - - if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) + if (scrub_fixup_io(READ, multi->stripes[i].dev->bdev, + multi->stripes[i].physical >> 9, + sbio->bio->bi_io_vec[ix].bv_page)) { /* I/O-error, this is not a good copy */ continue; + } - ret = scrub_fixup_check(fixup); - if (ret == 0) + if (scrub_fixup_check(sbio, ix) == 0) break; } if (i == multi->num_stripes) goto uncorrectable; /* - * the bio now contains good data, write it back + * bi_io_vec[ix].bv_page now contains good data, write it back */ - bio->bi_sector = fixup->physical >> 9; - bio->bi_bdev = sdev->dev->bdev; - bio->bi_size = PAGE_SIZE; - bio->bi_next = NULL; - bio->bi_flags |= 1 << BIO_UPTODATE; - bio->bi_comp_cpu = -1; - bio->bi_end_io = scrub_fixup_end_io; - bio->bi_private = &complete; - - submit_bio(REQ_WRITE, bio); - - wait_for_completion(&complete); - - if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) + if (scrub_fixup_io(WRITE, sdev->dev->bdev, + (sbio->physical + ix * PAGE_SIZE) >> 9, + sbio->bio->bi_io_vec[ix].bv_page)) { /* I/O-error, writeback failed, give up */ goto uncorrectable; + } kfree(multi); spin_lock(&sdev->stat_lock); @@ -488,7 +356,7 @@ static void scrub_fixup(struct scrub_fixup *fixup) if (printk_ratelimit()) printk(KERN_ERR "btrfs: fixed up at %llu\n", - (unsigned long long)fixup->logical); + (unsigned long long)logical); return; uncorrectable: @@ -499,7 +367,32 @@ uncorrectable: if (printk_ratelimit()) printk(KERN_ERR "btrfs: unable to fixup at %llu\n", - (unsigned long long)fixup->logical); + (unsigned long long)logical); +} + +static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector, + struct page *page) +{ + struct bio *bio = NULL; + int ret; + DECLARE_COMPLETION_ONSTACK(complete); + + /* we are going to wait on this IO */ + rw |= REQ_SYNC | REQ_UNPLUG; + + bio = bio_alloc(GFP_NOFS, 1); + bio->bi_bdev = bdev; + bio->bi_sector = sector; + bio_add_page(bio, page, PAGE_SIZE, 0); + bio->bi_end_io = scrub_fixup_end_io; + bio->bi_private = &complete; + submit_bio(rw, bio); + + wait_for_completion(&complete); + + ret = !test_bit(BIO_UPTODATE, &bio->bi_flags); + bio_put(bio); + return ret; } static void scrub_bio_end_io(struct bio *bio, int err) -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
