btrfs-progs: mkfs/rootdir: Introduce function to get end position of last device...

[platform/upstream/btrfs-progs.git] / mkfs / rootdir.c

diff --git a/mkfs/rootdir.c b/mkfs/rootdir.c
index 83a3191..0eb3f8f 100644 (file)
--- a/mkfs/rootdir.c
+++ b/mkfs/rootdir.c
@@ -26,6 +26,7 @@
 #include <fcntl.h>
 #include <ftw.h>
 #include "ctree.h"
+#include "volumes.h"
 #include "internal.h"
 #include "disk-io.h"
 #include "messages.h"
@@ -733,3 +734,46 @@ u64 btrfs_mkfs_size_dir(const char *dir_name, u64 sectorsize,
        *size_of_data_ret = num_of_data_chunks * default_chunk_size;
        return total_size;
 }
+
+/*
+ * Get the end position of the last device extent for given @devid;
+ * @size_ret is exclsuive (means it should be aligned to sectorsize)
+ */
+static int get_device_extent_end(struct btrfs_fs_info *fs_info,
+                                u64 devid, u64 *size_ret)
+{
+       struct btrfs_root *dev_root = fs_info->dev_root;
+       struct btrfs_key key;
+       struct btrfs_path path;
+       struct btrfs_dev_extent *de;
+       int ret;
+
+       key.objectid = devid;
+       key.type = BTRFS_DEV_EXTENT_KEY;
+       key.offset = (u64)-1;
+
+       btrfs_init_path(&path);
+       ret = btrfs_search_slot(NULL, dev_root, &key, &path, 0, 0);
+       /* Not really possible */
+       BUG_ON(ret == 0);
+
+       ret = btrfs_previous_item(dev_root, &path, devid, BTRFS_DEV_EXTENT_KEY);
+       if (ret < 0)
+               goto out;
+
+       /* No dev_extent at all, not really possible for rootdir case */
+       if (ret > 0) {
+               *size_ret = 0;
+               ret = -EUCLEAN;
+               goto out;
+       }
+
+       btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+       de = btrfs_item_ptr(path.nodes[0], path.slots[0],
+                           struct btrfs_dev_extent);
+       *size_ret = key.offset + btrfs_dev_extent_length(path.nodes[0], de);
+out:
+       btrfs_release_path(&path);
+
+       return ret;
+}