* Unlike inode.c in kernel, which can use most of the kernel infrastructure
* like inode/dentry things, in user-land, we can only use inode number to
* do directly operation on extent buffer, which may cause extra searching,
- * but should not be a huge problem since progs is less performence sensitive.
+ * but should not be a huge problem since progs is less performance sensitive.
*/
#include <sys/stat.h>
#include "transaction.h"
#include "disk-io.h"
#include "time.h"
+#include "messages.h"
/*
* Find a free inode index for later btrfs_add_link().
*/
int btrfs_add_link(struct btrfs_trans_handle *trans, struct btrfs_root *root,
u64 ino, u64 parent_ino, char *name, int namelen,
- u8 type, u64 *index, int add_backref)
+ u8 type, u64 *index, int add_backref, int ignore_existed)
{
struct btrfs_path *path;
struct btrfs_key key;
}
ret = check_dir_conflict(root, name, namelen, parent_ino, ret_index);
- if (ret < 0)
+ if (ret < 0 && !(ignore_existed && ret == -EEXIST))
goto out;
/* Add inode ref */
if (add_backref) {
ret = btrfs_insert_inode_ref(trans, root, name, namelen,
ino, parent_ino, ret_index);
- if (ret < 0)
+ if (ret < 0 && !(ignore_existed && ret == -EEXIST))
goto out;
- /* Update nlinks for the inode */
- key.objectid = ino;
- key.type = BTRFS_INODE_ITEM_KEY;
- key.offset = 0;
- ret = btrfs_search_slot(trans, root, &key, path, 1, 1);
- if (ret) {
- if (ret > 0)
- ret = -ENOENT;
- goto out;
+ /* do not update nlinks if existed */
+ if (!ret) {
+ /* Update nlinks for the inode */
+ key.objectid = ino;
+ key.type = BTRFS_INODE_ITEM_KEY;
+ key.offset = 0;
+ ret = btrfs_search_slot(trans, root, &key, path, 1, 1);
+ if (ret) {
+ if (ret > 0)
+ ret = -ENOENT;
+ goto out;
+ }
+ inode_item = btrfs_item_ptr(path->nodes[0],
+ path->slots[0], struct btrfs_inode_item);
+ nlink = btrfs_inode_nlink(path->nodes[0], inode_item);
+ nlink++;
+ btrfs_set_inode_nlink(path->nodes[0], inode_item,
+ nlink);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+ btrfs_release_path(path);
}
- inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
- struct btrfs_inode_item);
- nlink = btrfs_inode_nlink(path->nodes[0], inode_item);
- nlink++;
- btrfs_set_inode_nlink(path->nodes[0], inode_item, nlink);
- btrfs_mark_buffer_dirty(path->nodes[0]);
- btrfs_release_path(path);
}
/* Add dir_item and dir_index */
* dir_item if any of them exists.
*
* If an inode's nlink is reduced to 0 and 'add_orphan' is true, it will be
- * added to orphan inode and wairing to be deleted by next kernel mount.
+ * added to orphan inode and waiting to be deleted by next kernel mount.
*/
int btrfs_unlink(struct btrfs_trans_handle *trans, struct btrfs_root *root,
u64 ino, u64 parent_ino, u64 index, const char *name,
/* check the ref and backref exists */
inode_ref = btrfs_lookup_inode_ref(trans, root, path, name, namelen,
- ino, parent_ino, index, 0);
+ ino, parent_ino, 0);
if (IS_ERR(inode_ref)) {
ret = PTR_ERR(inode_ref);
goto out;
/* For nlinks == 0, add it to orphan list if needed */
if (nlinks == 0 && add_orphan) {
ret = btrfs_add_orphan_item(trans, root, path, ino);
+ if (ret < 0)
+ goto out;
btrfs_mark_buffer_dirty(path->nodes[0]);
btrfs_release_path(path);
}
btrfs_free_path(path);
return ret;
}
+
+/* Fill inode item with 'mode'. Uid/gid to root/root */
+static void fill_inode_item(struct btrfs_trans_handle *trans,
+ struct btrfs_inode_item *inode_item,
+ u32 mode, u32 nlink)
+{
+ time_t now = time(NULL);
+
+ btrfs_set_stack_inode_generation(inode_item, trans->transid);
+ btrfs_set_stack_inode_uid(inode_item, 0);
+ btrfs_set_stack_inode_gid(inode_item, 0);
+ btrfs_set_stack_inode_size(inode_item, 0);
+ btrfs_set_stack_inode_mode(inode_item, mode);
+ btrfs_set_stack_inode_nlink(inode_item, nlink);
+ btrfs_set_stack_timespec_sec(&inode_item->atime, now);
+ btrfs_set_stack_timespec_nsec(&inode_item->atime, 0);
+ btrfs_set_stack_timespec_sec(&inode_item->mtime, now);
+ btrfs_set_stack_timespec_nsec(&inode_item->mtime, 0);
+ btrfs_set_stack_timespec_sec(&inode_item->ctime, now);
+ btrfs_set_stack_timespec_nsec(&inode_item->ctime, 0);
+}
+
+/*
+ * Unlike kernel btrfs_new_inode(), we only create the INODE_ITEM, without
+ * its backref.
+ * The backref is added by btrfs_add_link().
+ */
+int btrfs_new_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+ u64 ino, u32 mode)
+{
+ struct btrfs_inode_item inode_item = {0};
+ int ret = 0;
+
+ fill_inode_item(trans, &inode_item, mode, 0);
+ ret = btrfs_insert_inode(trans, root, ino, &inode_item);
+ return ret;
+}
+
+/*
+ * Change inode flags to given value
+ */
+int btrfs_change_inode_flags(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 ino, u64 flags)
+{
+ struct btrfs_inode_item *item;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = ino;
+ key.type = BTRFS_INODE_ITEM_KEY;
+ key.offset = 0;
+
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+ if (ret < 0)
+ goto out;
+
+ item = btrfs_item_ptr(path->nodes[0], path->slots[0],
+ struct btrfs_inode_item);
+ btrfs_set_inode_flags(path->nodes[0], item, flags);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * Make a dir under the parent inode 'parent_ino' with 'name'
+ * and 'mode', The owner will be root/root.
+ */
+int btrfs_mkdir(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+ char *name, int namelen, u64 parent_ino, u64 *ino, int mode)
+{
+ struct btrfs_dir_item *dir_item;
+ struct btrfs_path *path;
+ u64 ret_ino = 0;
+ int ret = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ if (ino && *ino)
+ ret_ino = *ino;
+
+ dir_item = btrfs_lookup_dir_item(NULL, root, path, parent_ino,
+ name, namelen, 0);
+ if (IS_ERR(dir_item)) {
+ ret = PTR_ERR(dir_item);
+ goto out;
+ }
+
+ if (dir_item) {
+ struct btrfs_key found_key;
+
+ /*
+ * Already have conflicting name, check if it is a dir.
+ * Either way, no need to continue.
+ */
+ btrfs_dir_item_key_to_cpu(path->nodes[0], dir_item, &found_key);
+ ret_ino = found_key.objectid;
+ if (btrfs_dir_type(path->nodes[0], dir_item) != BTRFS_FT_DIR)
+ ret = -EEXIST;
+ goto out;
+ }
+
+ if (!ret_ino)
+ /*
+ * This is *UNSAFE* if some leaf is corrupted,
+ * only used as a fallback method. Caller should either
+ * ensure the fs is OK or pass ino with unused inode number.
+ */
+ ret = btrfs_find_free_objectid(NULL, root, parent_ino,
+ &ret_ino);
+ if (ret)
+ goto out;
+ ret = btrfs_new_inode(trans, root, ret_ino, mode | S_IFDIR);
+ if (ret)
+ goto out;
+ ret = btrfs_add_link(trans, root, ret_ino, parent_ino, name, namelen,
+ BTRFS_FT_DIR, NULL, 1, 0);
+ if (ret)
+ goto out;
+out:
+ btrfs_free_path(path);
+ if (ret == 0 && ino)
+ *ino = ret_ino;
+ return ret;
+}
+
+struct btrfs_root *btrfs_mksubvol(struct btrfs_root *root,
+ const char *base, u64 root_objectid,
+ bool convert)
+{
+ 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);
+ if (convert) {
+ 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;
+ }
+ }
+ } else {
+ ret = btrfs_insert_dir_item(trans, root, buf, len, dirid, &key,
+ BTRFS_FT_DIR, index);
+ }
+ 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;
+}