btrfs-progs: image: use on-stack path buffer in create_metadump

We don't need to conserve stack space too much unlike kernel, also
remove one error condition.

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

diff --git a/btrfs-image.c b/btrfs-image.c
index 0b915c6..81baeea 100644 (file)
--- a/btrfs-image.c
+++ b/btrfs-image.c
@@ -1328,7 +1328,7 @@ static int create_metadump(const char *input, FILE *out, int num_threads,
                           int compress_level, int sanitize, int walk_trees)
 {
        struct btrfs_root *root;
-       struct btrfs_path *path = NULL;
+       struct btrfs_path path;
        struct metadump_struct metadump;
        int ret;
        int err = 0;
@@ -1355,12 +1355,7 @@ static int create_metadump(const char *input, FILE *out, int num_threads,
                goto out;
        }
 
-       path = btrfs_alloc_path();
-       if (!path) {
-               error("not enough memory to allocate path");
-               err = -ENOMEM;
-               goto out;
-       }
+       btrfs_init_path(&path);
 
        if (walk_trees) {
                ret = copy_tree_blocks(root, root->fs_info->chunk_root->node,
@@ -1377,20 +1372,20 @@ static int create_metadump(const char *input, FILE *out, int num_threads,
                        goto out;
                }
        } else {
-               ret = copy_from_extent_tree(&metadump, path);
+               ret = copy_from_extent_tree(&metadump, &path);
                if (ret) {
                        err = ret;
                        goto out;
                }
        }
 
-       ret = copy_log_trees(root, &metadump, path);
+       ret = copy_log_trees(root, &metadump, &path);
        if (ret) {
                err = ret;
                goto out;
        }
 
-       ret = copy_space_cache(root, &metadump, path);
+       ret = copy_space_cache(root, &metadump, &path);
 out:
        ret = flush_pending(&metadump, 1);
        if (ret) {
@@ -1401,7 +1396,7 @@ out:
 
        metadump_destroy(&metadump, num_threads);
 
-       btrfs_free_path(path);
+       btrfs_release_path(&path);
        ret = close_ctree(root);
        return err ? err : ret;
 }