From 8a820b57656c1a062c6445f872a9169fa0d9b381 Mon Sep 17 00:00:00 2001 From: Yingyi Luo Date: Fri, 15 Sep 2017 10:49:21 -0700 Subject: btrfs-progs: convert: move link_subvol out of main link_subvol() is moved to inode.c and renamed as btrfs_mksubvol(). The change cascades down to the callchain. Signed-off-by: Yingyi Luo Signed-off-by: David Sterba --- inode.c | 124 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) (limited to 'inode.c') diff --git a/inode.c b/inode.c index 6b8bf40f..5dd816bf 100644 --- a/inode.c +++ b/inode.c @@ -28,6 +28,7 @@ #include "transaction.h" #include "disk-io.h" #include "time.h" +#include "messages.h" /* * Find a free inode index for later btrfs_add_link(). @@ -570,3 +571,126 @@ out: *ino = ret_ino; return ret; } + +struct btrfs_root *btrfs_mksubvol(struct btrfs_root *root, + const char *base, u64 root_objectid) +{ + struct btrfs_trans_handle *trans; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_root *new_root = NULL; + struct btrfs_path path; + struct btrfs_inode_item *inode_item; + struct extent_buffer *leaf; + struct btrfs_key key; + u64 dirid = btrfs_root_dirid(&root->root_item); + u64 index = 2; + char buf[BTRFS_NAME_LEN + 1]; /* for snprintf null */ + int len; + int i; + int ret; + + len = strlen(base); + if (len == 0 || len > BTRFS_NAME_LEN) + return NULL; + + btrfs_init_path(&path); + key.objectid = dirid; + key.type = BTRFS_DIR_INDEX_KEY; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0); + if (ret <= 0) { + error("search for DIR_INDEX dirid %llu failed: %d", + (unsigned long long)dirid, ret); + goto fail; + } + + if (path.slots[0] > 0) { + path.slots[0]--; + btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); + if (key.objectid == dirid && key.type == BTRFS_DIR_INDEX_KEY) + index = key.offset + 1; + } + btrfs_release_path(&path); + + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + error("unable to start transaction"); + goto fail; + } + + key.objectid = dirid; + key.offset = 0; + key.type = BTRFS_INODE_ITEM_KEY; + + ret = btrfs_lookup_inode(trans, root, &path, &key, 1); + if (ret) { + error("search for INODE_ITEM %llu failed: %d", + (unsigned long long)dirid, ret); + goto fail; + } + leaf = path.nodes[0]; + inode_item = btrfs_item_ptr(leaf, path.slots[0], + struct btrfs_inode_item); + + key.objectid = root_objectid; + key.offset = (u64)-1; + key.type = BTRFS_ROOT_ITEM_KEY; + + memcpy(buf, base, len); + for (i = 0; i < 1024; i++) { + ret = btrfs_insert_dir_item(trans, root, buf, len, + dirid, &key, BTRFS_FT_DIR, index); + if (ret != -EEXIST) + break; + len = snprintf(buf, ARRAY_SIZE(buf), "%s%d", base, i); + if (len < 1 || len > BTRFS_NAME_LEN) { + ret = -EINVAL; + break; + } + } + if (ret) + goto fail; + + btrfs_set_inode_size(leaf, inode_item, len * 2 + + btrfs_inode_size(leaf, inode_item)); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(&path); + + /* add the backref first */ + ret = btrfs_add_root_ref(trans, tree_root, root_objectid, + BTRFS_ROOT_BACKREF_KEY, + root->root_key.objectid, + dirid, index, buf, len); + if (ret) { + error("unable to add root backref for %llu: %d", + root->root_key.objectid, ret); + goto fail; + } + + /* now add the forward ref */ + ret = btrfs_add_root_ref(trans, tree_root, root->root_key.objectid, + BTRFS_ROOT_REF_KEY, root_objectid, + dirid, index, buf, len); + if (ret) { + error("unable to add root ref for %llu: %d", + root->root_key.objectid, ret); + goto fail; + } + + ret = btrfs_commit_transaction(trans, root); + if (ret) { + error("transaction commit failed: %d", ret); + goto fail; + } + + new_root = btrfs_read_fs_root(fs_info, &key); + if (IS_ERR(new_root)) { + error("unable to fs read root: %lu", PTR_ERR(new_root)); + new_root = NULL; + } +fail: + btrfs_init_path(&path); + return new_root; +} -- cgit v1.2.3