From 663db5a55486017ab6564b7014f0db97432598a0 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Thu, 15 Feb 2024 22:50:42 -0500 Subject: [PATCH] bcachefs: bch2_check_subvolume_structure() Now that we've got bch_subvolume.fs_path_parent, it's easy to write subvolume Signed-off-by: Kent Overstreet --- fs/bcachefs/fsck.c | 160 +++++++++++++++++++++++++++++------ fs/bcachefs/fsck.h | 1 + fs/bcachefs/recovery_types.h | 1 + 3 files changed, 135 insertions(+), 27 deletions(-) diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c index 797a5711216c..388f181eb0f2 100644 --- a/fs/bcachefs/fsck.c +++ b/fs/bcachefs/fsck.c @@ -342,6 +342,27 @@ static int remove_backpointer(struct btree_trans *trans, return ret; } +static int reattach_subvol(struct btree_trans *trans, struct bkey_s_c_subvolume s) +{ + struct bch_fs *c = trans->c; + + struct bch_inode_unpacked inode; + int ret = bch2_inode_find_by_inum_trans(trans, + (subvol_inum) { s.k->p.offset, le64_to_cpu(s.v->inode) }, + &inode); + if (ret) + return ret; + + ret = remove_backpointer(trans, &inode); + bch_err_msg(c, ret, "removing dirent"); + if (ret) + return ret; + + ret = reattach_inode(trans, &inode, le32_to_cpu(s.v->snapshot)); + bch_err_msg(c, ret, "reattaching inode %llu", inode.bi_inum); + return ret; +} + struct snapshots_seen_entry { u32 id; u32 equiv; @@ -2108,6 +2129,107 @@ int bch2_check_root(struct bch_fs *c) return ret; } +typedef DARRAY(u32) darray_u32; + +static bool darray_u32_has(darray_u32 *d, u32 v) +{ + darray_for_each(*d, i) + if (*i == v) + return true; + return false; +} + +/* + * We've checked that inode backpointers point to valid dirents; here, it's + * sufficient to check that the subvolume root has a dirent: + */ +static int subvol_has_dirent(struct btree_trans *trans, struct bkey_s_c_subvolume s) +{ + struct bch_inode_unpacked inode; + int ret = bch2_inode_find_by_inum_trans(trans, + (subvol_inum) { s.k->p.offset, le64_to_cpu(s.v->inode) }, + &inode); + if (ret) + return ret; + + return inode.bi_dir != 0; +} + +static int check_subvol_path(struct btree_trans *trans, struct btree_iter *iter, struct bkey_s_c k) +{ + struct bch_fs *c = trans->c; + struct btree_iter parent_iter = {}; + darray_u32 subvol_path = {}; + struct printbuf buf = PRINTBUF; + int ret = 0; + + if (k.k->type != KEY_TYPE_subvolume) + return 0; + + while (k.k->p.offset != BCACHEFS_ROOT_SUBVOL) { + ret = darray_push(&subvol_path, k.k->p.offset); + if (ret) + goto err; + + struct bkey_s_c_subvolume s = bkey_s_c_to_subvolume(k); + + ret = subvol_has_dirent(trans, s); + if (ret < 0) + break; + + if (fsck_err_on(!ret, + c, subvol_unreachable, + "unreachable subvolume %s", + (bch2_bkey_val_to_text(&buf, c, s.s_c), + buf.buf))) { + ret = reattach_subvol(trans, s); + break; + } + + u32 parent = le32_to_cpu(s.v->fs_path_parent); + + if (darray_u32_has(&subvol_path, parent)) { + if (fsck_err(c, subvol_loop, "subvolume loop")) + ret = reattach_subvol(trans, s); + break; + } + + bch2_trans_iter_exit(trans, &parent_iter); + bch2_trans_iter_init(trans, &parent_iter, + BTREE_ID_subvolumes, POS(0, parent), 0); + k = bch2_btree_iter_peek_slot(&parent_iter); + ret = bkey_err(k); + if (ret) + goto err; + + if (fsck_err_on(k.k->type != KEY_TYPE_subvolume, + c, subvol_unreachable, + "unreachable subvolume %s", + (bch2_bkey_val_to_text(&buf, c, s.s_c), + buf.buf))) { + ret = reattach_subvol(trans, s); + break; + } + } +fsck_err: +err: + printbuf_exit(&buf); + darray_exit(&subvol_path); + bch2_trans_iter_exit(trans, &parent_iter); + return ret; +} + +int bch2_check_subvolume_structure(struct bch_fs *c) +{ + int ret = bch2_trans_run(c, + for_each_btree_key_commit(trans, iter, + BTREE_ID_subvolumes, POS_MIN, BTREE_ITER_PREFETCH, k, + NULL, NULL, BCH_TRANS_COMMIT_no_enospc, + check_subvol_path(trans, &iter, k))); + bch_err_fn(c, ret); + return ret; +} + struct pathbuf_entry { u64 inum; u32 snapshot; @@ -2124,20 +2246,6 @@ static bool path_is_dup(pathbuf *p, u64 inum, u32 snapshot) return false; } -static int path_down(struct bch_fs *c, pathbuf *p, - u64 inum, u32 snapshot) -{ - int ret = darray_push(p, ((struct pathbuf_entry) { - .inum = inum, - .snapshot = snapshot, - })); - - if (ret) - bch_err(c, "fsck: error allocating memory for pathbuf, size %zu", - p->size); - return ret; -} - /* * Check that a given inode is reachable from the root: * @@ -2188,11 +2296,12 @@ static int check_path(struct btree_trans *trans, pathbuf *p, struct bkey_s_c ino if (!S_ISDIR(inode.bi_mode)) break; - ret = path_down(c, p, inode.bi_inum, snapshot); - if (ret) { - bch_err(c, "memory allocation failure"); + ret = darray_push(p, ((struct pathbuf_entry) { + .inum = inode.bi_inum, + .snapshot = snapshot, + })); + if (ret) return ret; - } snapshot = parent_snapshot; @@ -2219,18 +2328,15 @@ static int check_path(struct btree_trans *trans, pathbuf *p, struct bkey_s_c ino pr_err("%llu:%u", i->inum, i->snapshot); pr_err("%llu:%u", inode.bi_inum, snapshot); - if (!fsck_err(c, dir_loop, "directory structure loop")) - return 0; - - ret = remove_backpointer(trans, &inode); - if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart)) + if (fsck_err(c, dir_loop, "directory structure loop")) { + ret = remove_backpointer(trans, &inode); bch_err_msg(c, ret, "removing dirent"); - if (ret) - break; + if (ret) + break; - ret = reattach_inode(trans, &inode, snapshot); - if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart)) + ret = reattach_inode(trans, &inode, snapshot); bch_err_msg(c, ret, "reattaching inode %llu", inode.bi_inum); + } break; } } diff --git a/fs/bcachefs/fsck.h b/fs/bcachefs/fsck.h index da991e8cf27e..a4ef94271784 100644 --- a/fs/bcachefs/fsck.h +++ b/fs/bcachefs/fsck.h @@ -8,6 +8,7 @@ int bch2_check_indirect_extents(struct bch_fs *); int bch2_check_dirents(struct bch_fs *); int bch2_check_xattrs(struct bch_fs *); int bch2_check_root(struct bch_fs *); +int bch2_check_subvolume_structure(struct bch_fs *); int bch2_check_directory_structure(struct bch_fs *); int bch2_check_nlinks(struct bch_fs *); int bch2_fix_reflink_p(struct bch_fs *); diff --git a/fs/bcachefs/recovery_types.h b/fs/bcachefs/recovery_types.h index f0fc1dbb7239..1361e34d4e64 100644 --- a/fs/bcachefs/recovery_types.h +++ b/fs/bcachefs/recovery_types.h @@ -44,6 +44,7 @@ x(check_dirents, 27, PASS_FSCK) \ x(check_xattrs, 28, PASS_FSCK) \ x(check_root, 29, PASS_ONLINE|PASS_FSCK) \ + x(check_subvolume_structure, 36, PASS_ONLINE|PASS_FSCK) \ x(check_directory_structure, 30, PASS_ONLINE|PASS_FSCK) \ x(check_nlinks, 31, PASS_FSCK) \ x(delete_dead_inodes, 32, PASS_FSCK|PASS_UNCLEAN) \