From a6508079b1b6b231d16c438c384d718d3508573c Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Mon, 23 Sep 2024 22:22:00 -0400 Subject: [PATCH] bcachefs: dirent_points_to_inode() now warns on mismatch if an inode backpointer points to a dirent that doesn't point back, that's an error we should warn about. Signed-off-by: Kent Overstreet --- fs/bcachefs/fsck.c | 84 ++++++++++++++++++++++++++++++---------------- 1 file changed, 56 insertions(+), 28 deletions(-) diff --git a/fs/bcachefs/fsck.c b/fs/bcachefs/fsck.c index 9c10eeeb0bcb..0e397d0ef3dd 100644 --- a/fs/bcachefs/fsck.c +++ b/fs/bcachefs/fsck.c @@ -21,6 +21,49 @@ #include #include /* struct qstr */ +static bool inode_points_to_dirent(struct bch_inode_unpacked *inode, + struct bkey_s_c_dirent d) +{ + return inode->bi_dir == d.k->p.inode && + inode->bi_dir_offset == d.k->p.offset; +} + +static bool dirent_points_to_inode_nowarn(struct bkey_s_c_dirent d, + struct bch_inode_unpacked *inode) +{ + if (d.v->d_type == DT_SUBVOL + ? le32_to_cpu(d.v->d_child_subvol) == inode->bi_subvol + : le64_to_cpu(d.v->d_inum) == inode->bi_inum) + return 0; + return -BCH_ERR_ENOENT_dirent_doesnt_match_inode; +} + +static void dirent_inode_mismatch_msg(struct printbuf *out, + struct bch_fs *c, + struct bkey_s_c_dirent dirent, + struct bch_inode_unpacked *inode) +{ + prt_str(out, "inode points to dirent that does not point back:"); + prt_newline(out); + bch2_bkey_val_to_text(out, c, dirent.s_c); + prt_newline(out); + bch2_inode_unpacked_to_text(out, inode); +} + +static int dirent_points_to_inode(struct bch_fs *c, + struct bkey_s_c_dirent dirent, + struct bch_inode_unpacked *inode) +{ + int ret = dirent_points_to_inode_nowarn(dirent, inode); + if (ret) { + struct printbuf buf = PRINTBUF; + dirent_inode_mismatch_msg(&buf, c, dirent, inode); + bch_warn(c, "%s", buf.buf); + printbuf_exit(&buf); + } + return ret; +} + /* * XXX: this is handling transaction restarts without returning * -BCH_ERR_transaction_restart_nested, this is not how we do things anymore: @@ -371,7 +414,8 @@ static int reattach_subvol(struct btree_trans *trans, struct bkey_s_c_subvolume return ret; ret = remove_backpointer(trans, &inode); - bch_err_msg(c, ret, "removing dirent"); + if (!bch2_err_matches(ret, ENOENT)) + bch_err_msg(c, ret, "removing dirent"); if (ret) return ret; @@ -900,21 +944,6 @@ static struct bkey_s_c_dirent inode_get_dirent(struct btree_trans *trans, return dirent_get_by_pos(trans, iter, SPOS(inode->bi_dir, inode->bi_dir_offset, *snapshot)); } -static bool inode_points_to_dirent(struct bch_inode_unpacked *inode, - struct bkey_s_c_dirent d) -{ - return inode->bi_dir == d.k->p.inode && - inode->bi_dir_offset == d.k->p.offset; -} - -static bool dirent_points_to_inode(struct bkey_s_c_dirent d, - struct bch_inode_unpacked *inode) -{ - return d.v->d_type == DT_SUBVOL - ? le32_to_cpu(d.v->d_child_subvol) == inode->bi_subvol - : le64_to_cpu(d.v->d_inum) == inode->bi_inum; -} - static int check_inode_deleted_list(struct btree_trans *trans, struct bpos p) { struct btree_iter iter; @@ -924,13 +953,14 @@ static int check_inode_deleted_list(struct btree_trans *trans, struct bpos p) return ret; } -static int check_inode_dirent_inode(struct btree_trans *trans, struct bkey_s_c inode_k, +static int check_inode_dirent_inode(struct btree_trans *trans, struct bch_inode_unpacked *inode, - u32 inode_snapshot, bool *write_inode) + bool *write_inode) { struct bch_fs *c = trans->c; struct printbuf buf = PRINTBUF; + u32 inode_snapshot = inode->bi_snapshot; struct btree_iter dirent_iter = {}; struct bkey_s_c_dirent d = inode_get_dirent(trans, &dirent_iter, inode, &inode_snapshot); int ret = bkey_err(d); @@ -940,13 +970,13 @@ static int check_inode_dirent_inode(struct btree_trans *trans, struct bkey_s_c i if (fsck_err_on(ret, trans, inode_points_to_missing_dirent, "inode points to missing dirent\n%s", - (bch2_bkey_val_to_text(&buf, c, inode_k), buf.buf)) || - fsck_err_on(!ret && !dirent_points_to_inode(d, inode), + (bch2_inode_unpacked_to_text(&buf, inode), buf.buf)) || + fsck_err_on(!ret && dirent_points_to_inode_nowarn(d, inode), trans, inode_points_to_wrong_dirent, - "inode points to dirent that does not point back:\n%s", - (bch2_bkey_val_to_text(&buf, c, inode_k), - prt_newline(&buf), - bch2_bkey_val_to_text(&buf, c, d.s_c), buf.buf))) { + "%s", + (printbuf_reset(&buf), + dirent_inode_mismatch_msg(&buf, c, d, inode), + buf.buf))) { /* * We just clear the backpointer fields for now. If we find a * dirent that points to this inode in check_dirents(), we'll @@ -1145,7 +1175,7 @@ static int check_inode(struct btree_trans *trans, } if (u.bi_dir || u.bi_dir_offset) { - ret = check_inode_dirent_inode(trans, k, &u, k.k->p.snapshot, &do_update); + ret = check_inode_dirent_inode(trans, &u, &do_update); if (ret) goto err; } @@ -2474,10 +2504,8 @@ static int check_path(struct btree_trans *trans, pathbuf *p, struct bkey_s_c ino if (ret && !bch2_err_matches(ret, ENOENT)) break; - if (!ret && !dirent_points_to_inode(d, &inode)) { + if (!ret && (ret = dirent_points_to_inode(c, d, &inode))) bch2_trans_iter_exit(trans, &dirent_iter); - ret = -BCH_ERR_ENOENT_dirent_doesnt_match_inode; - } if (bch2_err_matches(ret, ENOENT)) { ret = 0; -- 2.25.1