bcachefs: Fsck locking improvements

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/dirent.c

@@ -329,17 +329,18 @@ u64 bch2_dirent_lookup(struct bch_fs *c, u64 dir_inum,
 	return inum;
 }
 
-int bch2_empty_dir(struct bch_fs *c, u64 dir_inum)
+int bch2_empty_dir_trans(struct btree_trans *trans, u64 dir_inum)
 {
-	struct btree_trans trans;
 	struct btree_iter *iter;
 	struct bkey_s_c k;
 	int ret = 0;
 
-	bch2_trans_init(&trans, c);
+	iter = bch2_trans_get_iter(trans, BTREE_ID_DIRENTS,
+				   POS(dir_inum, 0), 0);
+	if (IS_ERR(iter))
+		return PTR_ERR(iter);
 
-	for_each_btree_key(&trans, iter, BTREE_ID_DIRENTS,
-			   POS(dir_inum, 0), 0, k) {
+	for_each_btree_key_continue(iter, 0, k) {
 		if (k.k->p.inode > dir_inum)
 			break;
 
@@ -348,11 +349,17 @@ int bch2_empty_dir(struct bch_fs *c, u64 dir_inum)
 			break;
 		}
 	}
-	bch2_trans_exit(&trans);
+	bch2_trans_iter_put(trans, iter);
 
 	return ret;
 }
 
+int bch2_empty_dir(struct bch_fs *c, u64 dir_inum)
+{
+	return bch2_trans_do(c, NULL, 0,
+		bch2_empty_dir_trans(&trans, dir_inum));
+}
+
 int bch2_readdir(struct bch_fs *c, struct file *file,
 		 struct dir_context *ctx)
 {

fs/bcachefs/dirent.h

@@ -55,6 +55,7 @@ int bch2_dirent_rename(struct btree_trans *,
 u64 bch2_dirent_lookup(struct bch_fs *, u64, const struct bch_hash_info *,
 		       const struct qstr *);
 
+int bch2_empty_dir_trans(struct btree_trans *, u64);
 int bch2_empty_dir(struct bch_fs *, u64);
 int bch2_readdir(struct bch_fs *, struct file *, struct dir_context *);
 

fs/bcachefs/fsck.c

@@ -128,18 +128,21 @@ static struct inode_walker inode_walker_init(void)
 	};
 }
 
-static int walk_inode(struct bch_fs *c, struct inode_walker *w, u64 inum)
+static int walk_inode(struct btree_trans *trans,
+		      struct inode_walker *w, u64 inum)
 {
-	w->first_this_inode	= inum != w->cur_inum;
-	w->cur_inum		= inum;
-
-	if (w->first_this_inode) {
-		int ret = bch2_inode_find_by_inum(c, inum, &w->inode);
+	if (inum != w->cur_inum) {
+		int ret = bch2_inode_find_by_inum_trans(trans, inum,
+							&w->inode);
 
 		if (ret && ret != -ENOENT)
 			return ret;
 
-		w->have_inode = !ret;
+		w->have_inode	= !ret;
+		w->cur_inum	= inum;
+		w->first_this_inode = true;
+	} else {
+		w->first_this_inode = false;
 	}
 
 	return 0;
@@ -445,12 +448,15 @@ static int check_extents(struct bch_fs *c)
 	int ret = 0;
 
 	bch2_trans_init(&trans, c);
+	bch2_trans_preload_iters(&trans);
 
 	bch_verbose(c, "checking extents");
 
-	for_each_btree_key(&trans, iter, BTREE_ID_EXTENTS,
-			   POS(BCACHEFS_ROOT_INO, 0), 0, k) {
-		ret = walk_inode(c, &w, k.k->p.inode);
+	iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
+				   POS(BCACHEFS_ROOT_INO, 0), 0);
+retry:
+	for_each_btree_key_continue(iter, 0, k) {
+		ret = walk_inode(&trans, &w, k.k->p.inode);
 		if (ret)
 			break;
 
@@ -515,6 +521,8 @@ static int check_extents(struct bch_fs *c)
 	}
 err:
 fsck_err:
+	if (ret == -EINTR)
+		goto retry;
 	return bch2_trans_exit(&trans) ?: ret;
 }
 
@@ -537,21 +545,20 @@ static int check_dirents(struct bch_fs *c)
 	bch_verbose(c, "checking dirents");
 
 	bch2_trans_init(&trans, c);
-
 	bch2_trans_preload_iters(&trans);
 
-	iter = bch2_trans_get_iter(&trans, BTREE_ID_DIRENTS,
-				   POS(BCACHEFS_ROOT_INO, 0), 0);
-
 	hash_check_init(&h);
 
+	iter = bch2_trans_get_iter(&trans, BTREE_ID_DIRENTS,
+				   POS(BCACHEFS_ROOT_INO, 0), 0);
+retry:
 	for_each_btree_key_continue(iter, 0, k) {
 		struct bkey_s_c_dirent d;
 		struct bch_inode_unpacked target;
 		bool have_target;
 		u64 d_inum;
 
-		ret = walk_inode(c, &w, k.k->p.inode);
+		ret = walk_inode(&trans, &w, k.k->p.inode);
 		if (ret)
 			break;
 
@@ -620,7 +627,7 @@ static int check_dirents(struct bch_fs *c)
 			continue;
 		}
 
-		ret = bch2_inode_find_by_inum(c, d_inum, &target);
+		ret = bch2_inode_find_by_inum_trans(&trans, d_inum, &target);
 		if (ret && ret != -ENOENT)
 			break;
 
@@ -671,6 +678,9 @@ static int check_dirents(struct bch_fs *c)
 	hash_stop_chain(&trans, &h);
 err:
 fsck_err:
+	if (ret == -EINTR)
+		goto retry;
+
 	return bch2_trans_exit(&trans) ?: ret;
 }
 
@@ -689,17 +699,16 @@ static int check_xattrs(struct bch_fs *c)
 
 	bch_verbose(c, "checking xattrs");
 
-	bch2_trans_init(&trans, c);
+	hash_check_init(&h);
 
+	bch2_trans_init(&trans, c);
 	bch2_trans_preload_iters(&trans);
 
 	iter = bch2_trans_get_iter(&trans, BTREE_ID_XATTRS,
 				   POS(BCACHEFS_ROOT_INO, 0), 0);
-
-	hash_check_init(&h);
-
+retry:
 	for_each_btree_key_continue(iter, 0, k) {
-		ret = walk_inode(c, &w, k.k->p.inode);
+		ret = walk_inode(&trans, &w, k.k->p.inode);
 		if (ret)
 			break;
 
@@ -722,6 +731,8 @@ static int check_xattrs(struct bch_fs *c)
 	}
 err:
 fsck_err:
+	if (ret == -EINTR)
+		goto retry;
 	return bch2_trans_exit(&trans) ?: ret;
 }
 
@@ -905,6 +916,7 @@ static int check_directory_structure(struct bch_fs *c,
 	int ret = 0;
 
 	bch2_trans_init(&trans, c);
+	bch2_trans_preload_iters(&trans);
 
 	bch_verbose(c, "checking directory structure");
 
@@ -919,9 +931,8 @@ static int check_directory_structure(struct bch_fs *c,
 	}
 
 	ret = path_down(&path, BCACHEFS_ROOT_INO);
-	if (ret) {
-		return ret;
-	}
+	if (ret)
+		goto err;
 
 	while (path.nr) {
 next:
@@ -983,14 +994,19 @@ static int check_directory_structure(struct bch_fs *c,
 		path.nr--;
 	}
 
-	for_each_btree_key(&trans, iter, BTREE_ID_INODES, POS_MIN, 0, k) {
+	iter = bch2_trans_get_iter(&trans, BTREE_ID_INODES, POS_MIN, 0);
+retry:
+	for_each_btree_key_continue(iter, 0, k) {
 		if (k.k->type != KEY_TYPE_inode)
 			continue;
 
 		if (!S_ISDIR(le16_to_cpu(bkey_s_c_to_inode(k).v->bi_mode)))
 			continue;
 
-		if (!bch2_empty_dir(c, k.k->p.inode))
+		ret = bch2_empty_dir_trans(&trans, k.k->p.inode);
+		if (ret == -EINTR)
+			goto retry;
+		if (!ret)
 			continue;
 
 		if (fsck_err_on(!inode_bitmap_test(&dirs_done, k.k->p.inode), c,
@@ -1018,15 +1034,12 @@ static int check_directory_structure(struct bch_fs *c,
 		memset(&path, 0, sizeof(path));
 		goto restart_dfs;
 	}
-
-out:
-	kfree(dirs_done.bits);
-	kfree(path.entries);
-	return ret;
 err:
 fsck_err:
 	ret = bch2_trans_exit(&trans) ?: ret;
-	goto out;
+	kfree(dirs_done.bits);
+	kfree(path.entries);
+	return ret;
 }
 
 struct nlink {
@@ -1070,6 +1083,7 @@ static int bch2_gc_walk_dirents(struct bch_fs *c, nlink_table *links,
 	int ret;
 
 	bch2_trans_init(&trans, c);
+	bch2_trans_preload_iters(&trans);
 
 	inc_link(c, links, range_start, range_end, BCACHEFS_ROOT_INO, false);
 
@@ -1327,6 +1341,7 @@ static int bch2_gc_walk_inodes(struct bch_fs *c,
 	u64 nlinks_pos;
 
 	bch2_trans_init(&trans, c);
+	bch2_trans_preload_iters(&trans);
 
 	iter = bch2_trans_get_iter(&trans, BTREE_ID_INODES,
 				   POS(range_start, 0), 0);
@@ -1426,6 +1441,7 @@ static int check_inodes_fast(struct bch_fs *c)
 	int ret = 0, ret2;
 
 	bch2_trans_init(&trans, c);
+	bch2_trans_preload_iters(&trans);
 
 	iter = bch2_trans_get_iter(&trans, BTREE_ID_INODES,
 				   POS_MIN, 0);

fs/bcachefs/inode.c

@@ -444,31 +444,32 @@ int bch2_inode_rm(struct bch_fs *c, u64 inode_nr)
 	return ret;
 }
 
-int bch2_inode_find_by_inum(struct bch_fs *c, u64 inode_nr,
-			    struct bch_inode_unpacked *inode)
+int bch2_inode_find_by_inum_trans(struct btree_trans *trans, u64 inode_nr,
+				  struct bch_inode_unpacked *inode)
 {
-	struct btree_trans trans;
 	struct btree_iter *iter;
 	struct bkey_s_c k;
 	int ret = -ENOENT;
 
-	bch2_trans_init(&trans, c);
+	iter = bch2_trans_get_iter(trans, BTREE_ID_INODES,
+			POS(inode_nr, 0), BTREE_ITER_SLOTS);
+	if (IS_ERR(iter))
+		return PTR_ERR(iter);
 
-	for_each_btree_key(&trans, iter, BTREE_ID_INODES,
-			   POS(inode_nr, 0), BTREE_ITER_SLOTS, k) {
-		switch (k.k->type) {
-		case KEY_TYPE_inode:
-			ret = bch2_inode_unpack(bkey_s_c_to_inode(k), inode);
-			break;
-		default:
-			/* hole, not found */
-			break;
-		}
+	k = bch2_btree_iter_peek_slot(iter);
+	if (k.k->type == KEY_TYPE_inode)
+		ret = bch2_inode_unpack(bkey_s_c_to_inode(k), inode);
 
-		break;
-	}
+	bch2_trans_iter_put(trans, iter);
 
-	return bch2_trans_exit(&trans) ?: ret;
+	return ret;
+}
+
+int bch2_inode_find_by_inum(struct bch_fs *c, u64 inode_nr,
+			    struct bch_inode_unpacked *inode)
+{
+	return bch2_trans_do(c, NULL, 0,
+		bch2_inode_find_by_inum_trans(&trans, inode_nr, inode));
 }
 
 #ifdef CONFIG_BCACHEFS_DEBUG

fs/bcachefs/inode.h

@@ -60,8 +60,9 @@ int bch2_inode_create(struct bch_fs *, struct bch_inode_unpacked *,
 
 int bch2_inode_rm(struct bch_fs *, u64);
 
-int bch2_inode_find_by_inum(struct bch_fs *, u64,
-			   struct bch_inode_unpacked *);
+int bch2_inode_find_by_inum_trans(struct btree_trans *, u64,
+				  struct bch_inode_unpacked *);
+int bch2_inode_find_by_inum(struct bch_fs *, u64, struct bch_inode_unpacked *);
 
 static inline struct bch_io_opts bch2_inode_opts_get(struct bch_inode_unpacked *inode)
 {