Use the new dev extent based shrink method for rootdir option.
Signed-off-by: Qu Wenruo <w...@suse.com>
---
mkfs/main.c | 5 +++
mkfs/rootdir.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
mkfs/rootdir.h | 1 +
3 files changed, 117 insertions(+)
diff --git a/mkfs/main.c b/mkfs/main.c
index 7b78cfe3550e..0866e40d155f 100644
--- a/mkfs/main.c
+++ b/mkfs/main.c
@@ -1154,6 +1154,11 @@ raid_groups:
error("error wihle filling filesystem: %d", ret);
goto out;
}
+ ret = btrfs_mkfs_shrink_fs(fs_info, NULL);
+ if (ret < 0) {
+ error("error while shrinking filesystem: %d", ret);
+ goto out;
+ }
}
if (verbose) {
diff --git a/mkfs/rootdir.c b/mkfs/rootdir.c
index 1ca37996a3b3..9593bbc25b39 100644
--- a/mkfs/rootdir.c
+++ b/mkfs/rootdir.c
@@ -821,3 +821,114 @@ out:
btrfs_release_path(&path);
return ret;
}
+
+/*
+ * Set device size to @new_size.
+ *
+ * Only used for --rootdir option.
+ * We will need to reset the following values:
+ * 1) dev item in chunk tree
+ * 2) super->dev_item
+ * 3) super->total_bytes
+ */
+static int set_device_size(struct btrfs_fs_info *fs_info,
+ struct btrfs_device *device, u64 new_size)
+{
+ struct btrfs_root *chunk_root = fs_info->chunk_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_dev_item *di;
+ struct btrfs_path path;
+ struct btrfs_key key;
+ int ret;
+
+ /*
+ * Update in-meory device->total_bytes, so that at trans commit time,
+ * it super->dev_item will also get updated
+ */
+ device->total_bytes = new_size;
+ btrfs_init_path(&path);
+
+ /* Update device item in chunk tree */
+ trans = btrfs_start_transaction(chunk_root, 1);
+ if (IS_ERR(trans)) {
+ ret = PTR_ERR(trans);
+ error("failed to start transaction: %d (%s)", ret,
+ strerror(-ret));
+ return ret;
+ }
+ key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+ key.type = BTRFS_DEV_ITEM_KEY;
+ key.offset = device->devid;
+
+ ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1);
+ if (ret < 0)
+ goto err;
+ if (ret > 0)
+ ret = -ENOENT;
+ di = btrfs_item_ptr(path.nodes[0], path.slots[0],
+ struct btrfs_dev_item);
+ btrfs_set_device_total_bytes(path.nodes[0], di, new_size);
+ btrfs_mark_buffer_dirty(path.nodes[0]);
+
+ /*
+ * Update super->total_bytes, since it's only used for --rootdir,
+ * there is only one device, just use the @new_size.
+ */
+ btrfs_set_super_total_bytes(fs_info->super_copy, new_size);
+
+ /*
+ * Commit transaction to reflect the updated super->total_bytes and
+ * super->dev_item
+ */
+ ret = btrfs_commit_transaction(trans, chunk_root);
+ if (ret < 0)
+ error("failed to commit current transaction: %d (%s)",
+ ret, strerror(-ret));
+ btrfs_release_path(&path);
+ return ret;
+
+err:
+ btrfs_release_path(&path);
+ /*
+ * Commit trans here won't cause problem since the fs still has
+ * bad magic, and something wrong already happened, we don't
+ * care the return value anyway.
+ */
+ btrfs_commit_transaction(trans, chunk_root);
+ return ret;
+}
+
+int btrfs_mkfs_shrink_fs(struct btrfs_fs_info *fs_info, u64 *new_size_ret)
+{
+ u64 new_size;
+ struct btrfs_device *device;
+ struct list_head *cur;
+ int nr_devs = 0;
+ int ret;
+
+ list_for_each(cur, &fs_info->fs_devices->devices)
+ nr_devs++;
+
+ if (nr_devs > 1) {
+ error("cannot shrink fs with more than 1 device");
+ return -ENOTTY;
+ }
+
+ ret = get_device_extent_end(fs_info, 1, &new_size);
+ if (ret < 0) {
+ error("failed to get minimal device size: %d (%s)",
+ ret, strerror(-ret));
+ return ret;
+ }
+
+ BUG_ON(!IS_ALIGNED(new_size, fs_info->sectorsize));
+
+ device = list_entry(fs_info->fs_devices->devices.next,
+ struct btrfs_device, dev_list);
+ ret = set_device_size(fs_info, device, new_size);
+ if (ret < 0)
+ return ret;
+ if (new_size_ret)
+ *new_size_ret = new_size;
+ return ret;
+}
diff --git a/mkfs/rootdir.h b/mkfs/rootdir.h
index 75169f37e026..e5b739ede48a 100644
--- a/mkfs/rootdir.h
+++ b/mkfs/rootdir.h
@@ -29,4 +29,5 @@ int btrfs_mkfs_fill_dir(const char *source_dir, struct
btrfs_root *root,
bool verbose);
u64 btrfs_mkfs_size_dir(const char *dir_name, u32 sectorsize, u64 min_dev_size,
u64 meta_profile, u64 data_profile);
+int btrfs_mkfs_shrink_fs(struct btrfs_fs_info *fs_info, u64 *new_size_ret);
#endif
--
2.14.2
--
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