diff options
| -rw-r--r-- | fs/btrfs/scrub.c | 92 |
1 files changed, 67 insertions, 25 deletions
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 97142a218f0a..eba42e5fd5fd 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -24,6 +24,7 @@ #include "ordered-data.h" #include "transaction.h" #include "backref.h" +#include "extent_io.h" /* * This is only the first step towards a full-features scrub. It reads all @@ -360,13 +361,13 @@ out: static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx) { - struct page *page; + struct page *page = NULL; unsigned long index; struct scrub_fixup_nodatasum *fixup = ctx; int ret; - int corrected; + int corrected = 0; struct btrfs_key key; - struct inode *inode; + struct inode *inode = NULL; u64 end = offset + PAGE_SIZE - 1; struct btrfs_root *local_root; @@ -384,34 +385,75 @@ static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx) if (IS_ERR(inode)) return PTR_ERR(inode); - ret = set_extent_bit(&BTRFS_I(inode)->io_tree, offset, end, - EXTENT_DAMAGED, 0, NULL, NULL, GFP_NOFS); - - /* set_extent_bit should either succeed or give proper error */ - WARN_ON(ret > 0); - if (ret) - return ret < 0 ? ret : -EFAULT; - index = offset >> PAGE_CACHE_SHIFT; page = find_or_create_page(inode->i_mapping, index, GFP_NOFS); - if (!page) - return -ENOMEM; + if (!page) { + ret = -ENOMEM; + goto out; + } + + if (PageUptodate(page)) { + struct btrfs_mapping_tree *map_tree; + if (PageDirty(page)) { + /* + * we need to write the data to the defect sector. the + * data that was in that sector is not in memory, + * because the page was modified. we must not write the + * modified page to that sector. + * + * TODO: what could be done here: wait for the delalloc + * runner to write out that page (might involve + * COW) and see whether the sector is still + * referenced afterwards. + * + * For the meantime, we'll treat this error + * incorrectable, although there is a chance that a + * later scrub will find the bad sector again and that + * there's no dirty page in memory, then. + */ + ret = -EIO; + goto out; + } + map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree; + ret = repair_io_failure(map_tree, offset, PAGE_SIZE, + fixup->logical, page, + fixup->mirror_num); + unlock_page(page); + corrected = !ret; + } else { + /* + * we need to get good data first. the general readpage path + * will call repair_io_failure for us, we just have to make + * sure we read the bad mirror. + */ + ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end, + EXTENT_DAMAGED, GFP_NOFS); + if (ret) { + /* set_extent_bits should give proper error */ + WARN_ON(ret > 0); + if (ret > 0) + ret = -EFAULT; + goto out; + } - ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page, - btrfs_get_extent, fixup->mirror_num); - wait_on_page_locked(page); - corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset, end, - EXTENT_DAMAGED, 0, NULL); + ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page, + btrfs_get_extent, + fixup->mirror_num); + wait_on_page_locked(page); - if (corrected) - WARN_ON(!PageUptodate(page)); - else - clear_extent_bit(&BTRFS_I(inode)->io_tree, offset, end, - EXTENT_DAMAGED, 0, 0, NULL, GFP_NOFS); + corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset, + end, EXTENT_DAMAGED, 0, NULL); + if (!corrected) + clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end, + EXTENT_DAMAGED, GFP_NOFS); + } - put_page(page); - iput(inode); +out: + if (page) + put_page(page); + if (inode) + iput(inode); if (ret < 0) return ret; |