btrfs: use a structure to pass arguments to backref walking functions

The public backref walking functions have quite a lot of arguments that
are passed down the call stack to find_parent_nodes(), the core function
of the backref walking code.

The next patches in series will need to add even arguments to these
functions that should be passed not only to find_parent_nodes(), but also
to other functions used by the later (directly or even lower in the call
stack).

So create a structure to hold all these arguments and state used by the
main backref walking function, find_parent_nodes(), and use it as the
argument for the public backref walking functions iterate_extent_inodes(),
btrfs_find_all_leafs() and btrfs_find_all_roots().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 40 insertions, 10 deletions

diff --git a/fs/btrfs/tests/qgroup-tests.c b/fs/btrfs/tests/qgroup-tests.c
index 65b65d55d1f6..3fc8dc3fd980 100644
--- a/fs/btrfs/tests/qgroup-tests.c
+++ b/fs/btrfs/tests/qgroup-tests.c
@@ -205,6 +205,7 @@ static int remove_extent_ref(struct btrfs_root *root, u64 bytenr,
 static int test_no_shared_qgroup(struct btrfs_root *root,
 		u32 sectorsize, u32 nodesize)
 {
+	struct btrfs_backref_walk_ctx ctx = { 0 };
 	struct btrfs_trans_handle trans;
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct ulist *old_roots = NULL;
@@ -220,16 +221,22 @@ static int test_no_shared_qgroup(struct btrfs_root *root,
 		return ret;
 	}
 
+	ctx.bytenr = nodesize;
+	ctx.trans = &trans;
+	ctx.fs_info = fs_info;
+
 	/*
 	 * Since the test trans doesn't have the complicated delayed refs,
 	 * we can only call btrfs_qgroup_account_extent() directly to test
 	 * quota.
 	 */
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	old_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = insert_normal_tree_ref(root, nodesize, nodesize, 0,
 				BTRFS_FS_TREE_OBJECTID);
@@ -238,12 +245,14 @@ static int test_no_shared_qgroup(struct btrfs_root *root,
 		return ret;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		ulist_free(old_roots);
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	new_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = btrfs_qgroup_account_extent(&trans, nodesize, nodesize, old_roots,
 					  new_roots);
@@ -262,11 +271,13 @@ static int test_no_shared_qgroup(struct btrfs_root *root,
 		return -EINVAL;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	old_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = remove_extent_item(root, nodesize, nodesize);
 	if (ret) {
@@ -274,12 +285,14 @@ static int test_no_shared_qgroup(struct btrfs_root *root,
 		return -EINVAL;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		ulist_free(old_roots);
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	new_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = btrfs_qgroup_account_extent(&trans, nodesize, nodesize, old_roots,
 					  new_roots);
@@ -304,6 +317,7 @@ static int test_no_shared_qgroup(struct btrfs_root *root,
 static int test_multiple_refs(struct btrfs_root *root,
 		u32 sectorsize, u32 nodesize)
 {
+	struct btrfs_backref_walk_ctx ctx = { 0 };
 	struct btrfs_trans_handle trans;
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct ulist *old_roots = NULL;
@@ -324,11 +338,17 @@ static int test_multiple_refs(struct btrfs_root *root,
 		return ret;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, false);
+	ctx.bytenr = nodesize;
+	ctx.trans = &trans;
+	ctx.fs_info = fs_info;
+
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	old_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = insert_normal_tree_ref(root, nodesize, nodesize, 0,
 				BTRFS_FS_TREE_OBJECTID);
@@ -337,12 +357,14 @@ static int test_multiple_refs(struct btrfs_root *root,
 		return ret;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		ulist_free(old_roots);
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	new_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = btrfs_qgroup_account_extent(&trans, nodesize, nodesize, old_roots,
 					  new_roots);
@@ -357,11 +379,13 @@ static int test_multiple_refs(struct btrfs_root *root,
 		return -EINVAL;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	old_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = add_tree_ref(root, nodesize, nodesize, 0,
 			BTRFS_FIRST_FREE_OBJECTID);
@@ -370,12 +394,14 @@ static int test_multiple_refs(struct btrfs_root *root,
 		return ret;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		ulist_free(old_roots);
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	new_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = btrfs_qgroup_account_extent(&trans, nodesize, nodesize, old_roots,
 					  new_roots);
@@ -396,11 +422,13 @@ static int test_multiple_refs(struct btrfs_root *root,
 		return -EINVAL;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	old_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = remove_extent_ref(root, nodesize, nodesize, 0,
 				BTRFS_FIRST_FREE_OBJECTID);
@@ -409,12 +437,14 @@ static int test_multiple_refs(struct btrfs_root *root,
 		return ret;
 	}
 
-	ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, false);
+	ret = btrfs_find_all_roots(&ctx, false);
 	if (ret) {
 		ulist_free(old_roots);
 		test_err("couldn't find old roots: %d", ret);
 		return ret;
 	}
+	new_roots = ctx.roots;
+	ctx.roots = NULL;
 
 	ret = btrfs_qgroup_account_extent(&trans, nodesize, nodesize, old_roots,
 					  new_roots);