From 888ba4a1f1884e95384b6e28a9f0afed952ee0b2 Mon Sep 17 00:00:00 2001 From: Arne Jansen Date: Fri, 11 Nov 2011 08:17:10 -0500 Subject: [PATCH] Btrfs: handle bio_add_page failure gracefully in scrub Currently scrub fails with ENOMEM when bio_add_page fails. Unfortunately dm based targets accept only one page per bio, thus making scrub always fails. This patch just submits the current bio when an error is encountered and starts a new one. Signed-off-by: Arne Jansen Signed-off-by: Chris Mason --- fs/btrfs/scrub.c | 64 ++++++++++++++++++++++-------------------------- 1 file changed, 29 insertions(+), 35 deletions(-) diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index ed11d3866afde..f4190f22edfb2 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -944,50 +944,18 @@ static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer) static int scrub_submit(struct scrub_dev *sdev) { struct scrub_bio *sbio; - struct bio *bio; - int i; if (sdev->curr == -1) return 0; sbio = sdev->bios[sdev->curr]; - - bio = bio_alloc(GFP_NOFS, sbio->count); - if (!bio) - goto nomem; - - bio->bi_private = sbio; - bio->bi_end_io = scrub_bio_end_io; - bio->bi_bdev = sdev->dev->bdev; - bio->bi_sector = sbio->physical >> 9; - - for (i = 0; i < sbio->count; ++i) { - struct page *page; - int ret; - - page = alloc_page(GFP_NOFS); - if (!page) - goto nomem; - - ret = bio_add_page(bio, page, PAGE_SIZE, 0); - if (!ret) { - __free_page(page); - goto nomem; - } - } - sbio->err = 0; sdev->curr = -1; atomic_inc(&sdev->in_flight); - submit_bio(READ, bio); + submit_bio(READ, sbio->bio); return 0; - -nomem: - scrub_free_bio(bio); - - return -ENOMEM; } static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len, @@ -995,6 +963,8 @@ static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len, u8 *csum, int force) { struct scrub_bio *sbio; + struct page *page; + int ret; again: /* @@ -1015,12 +985,22 @@ again: } sbio = sdev->bios[sdev->curr]; if (sbio->count == 0) { + struct bio *bio; + sbio->physical = physical; sbio->logical = logical; + bio = bio_alloc(GFP_NOFS, SCRUB_PAGES_PER_BIO); + if (!bio) + return -ENOMEM; + + bio->bi_private = sbio; + bio->bi_end_io = scrub_bio_end_io; + bio->bi_bdev = sdev->dev->bdev; + bio->bi_sector = sbio->physical >> 9; + sbio->err = 0; + sbio->bio = bio; } else if (sbio->physical + sbio->count * PAGE_SIZE != physical || sbio->logical + sbio->count * PAGE_SIZE != logical) { - int ret; - ret = scrub_submit(sdev); if (ret) return ret; @@ -1030,6 +1010,20 @@ again: sbio->spag[sbio->count].generation = gen; sbio->spag[sbio->count].have_csum = 0; sbio->spag[sbio->count].mirror_num = mirror_num; + + page = alloc_page(GFP_NOFS); + if (!page) + return -ENOMEM; + + ret = bio_add_page(sbio->bio, page, PAGE_SIZE, 0); + if (!ret) { + __free_page(page); + ret = scrub_submit(sdev); + if (ret) + return ret; + goto again; + } + if (csum) { sbio->spag[sbio->count].have_csum = 1; memcpy(sbio->spag[sbio->count].csum, csum, sdev->csum_size); -- 2.39.5