struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
const char *name, u16 name_len,
int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
struct btrfs_key found_key;
struct extent_buffer *leaf;
key.objectid = dir;
btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY);
key.offset = btrfs_name_hash(name, name_len);
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0) {
if (path->slots[0] == 0)
return NULL;
path->slots[0]--;
}
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.objectid != dir ||
btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY ||
found_key.offset != key.offset)
return NULL;
return btrfs_match_dir_item_name(root, path, name, name_len);
}
int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
const char *name, int name_len)
{
int ret;
struct btrfs_key key;
struct btrfs_dir_item *di;
int data_size;
struct extent_buffer *leaf;
int slot;
struct btrfs_path *path;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = dir;
btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
key.offset = btrfs_name_hash(name, name_len);
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
/* return back any errors */
if (ret < 0)
goto out;
/* nothing found, we're safe */
if (ret > 0) {
ret = 0;
goto out;
}
/* we found an item, look for our name in the item */
di = btrfs_match_dir_item_name(root, path, name, name_len);
if (di) {
/* our exact name was found */
ret = -EEXIST;
goto out;
}
/*
* see if there is room in the item to insert this
* name
*/
data_size = sizeof(*di) + name_len;
leaf = path->nodes[0];
slot = path->slots[0];
if (data_size + btrfs_item_size_nr(leaf, slot) +
sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root)) {
ret = -EOVERFLOW;
} else {
/* plenty of insertion room */
ret = 0;
}
out:
btrfs_free_path(path);
return ret;
}
int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, char *name, int name_len, u64 dir,
struct btrfs_key *location, u8 type)
{
int ret = 0;
struct btrfs_path path;
struct btrfs_dir_item *dir_item;
char *name_ptr;
struct btrfs_key key;
u32 data_size;
key.objectid = dir;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
if (name_len == 1 && *name == '.')
key.offset = 1;
else if (name_len == 2 && name[0] == '.' && name[1] == '.')
key.offset = 2;
else
ret = btrfs_name_hash(name, name_len, &key.offset);
BUG_ON(ret);
btrfs_init_path(&path);
data_size = sizeof(*dir_item) + name_len;
dir_item = insert_with_overflow(trans, root, &path, &key, data_size);
if (!dir_item) {
ret = -1;
goto out;
}
btrfs_cpu_key_to_disk(&dir_item->location, location);
btrfs_set_dir_type(dir_item, type);
btrfs_set_dir_flags(dir_item, 0);
btrfs_set_dir_name_len(dir_item, name_len);
name_ptr = (char *)(dir_item + 1);
memcpy(name_ptr, name, name_len);
/* FIXME, use some real flag for selecting the extra index */
if (root == root->fs_info->tree_root)
goto out;
btrfs_release_path(root, &path);
btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
key.offset = location->objectid;
dir_item = insert_with_overflow(trans, root, &path, &key, data_size);
if (!dir_item) {
ret = -1;
goto out;
}
btrfs_cpu_key_to_disk(&dir_item->location, location);
btrfs_set_dir_type(dir_item, type);
btrfs_set_dir_flags(dir_item, 0);
btrfs_set_dir_name_len(dir_item, name_len);
name_ptr = (char *)(dir_item + 1);
memcpy(name_ptr, name, name_len);
out:
btrfs_release_path(root, &path);
return ret;
}
/*
* xattrs work a lot like directories, this inserts an xattr item
* into the tree
*/
int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root, const char *name,
u16 name_len, const void *data, u16 data_len,
u64 dir)
{
int ret = 0;
struct btrfs_path *path;
struct btrfs_dir_item *dir_item;
unsigned long name_ptr, data_ptr;
struct btrfs_key key, location;
struct btrfs_disk_key disk_key;
struct extent_buffer *leaf;
u32 data_size;
key.objectid = dir;
btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY);
key.offset = btrfs_name_hash(name, name_len);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
if (name_len + data_len + sizeof(struct btrfs_dir_item) >
BTRFS_LEAF_DATA_SIZE(root) - sizeof(struct btrfs_item))
return -ENOSPC;
data_size = sizeof(*dir_item) + name_len + data_len;
dir_item = insert_with_overflow(trans, root, path, &key, data_size,
name, name_len);
/*
* FIXME: at some point we should handle xattr's that are larger than
* what we can fit in our leaf. We set location to NULL b/c we arent
* pointing at anything else, that will change if we store the xattr
* data in a separate inode.
*/
BUG_ON(IS_ERR(dir_item));
memset(&location, 0, sizeof(location));
leaf = path->nodes[0];
btrfs_cpu_key_to_disk(&disk_key, &location);
btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
btrfs_set_dir_type(leaf, dir_item, BTRFS_FT_XATTR);
btrfs_set_dir_name_len(leaf, dir_item, name_len);
btrfs_set_dir_transid(leaf, dir_item, trans->transid);
btrfs_set_dir_data_len(leaf, dir_item, data_len);
name_ptr = (unsigned long)(dir_item + 1);
data_ptr = (unsigned long)((char *)name_ptr + name_len);
write_extent_buffer(leaf, name, name_ptr, name_len);
write_extent_buffer(leaf, data, data_ptr, data_len);
btrfs_mark_buffer_dirty(path->nodes[0]);
btrfs_free_path(path);
return ret;
}
int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, u64 dir, char *name,
int name_len, int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
key.objectid = dir;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
ret = btrfs_name_hash(name, name_len, &key.offset);
BUG_ON(ret);
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
return ret;
}
int main() {
u64 result;
int ret;
char line[255];
char *p;
while(1) {
p = fgets(line, 255, stdin);
if (!p)
break;
if (strlen(line) == 0)
continue;
if (line[strlen(line)-1] == '\n')
line[strlen(line)-1] = '\0';
result = btrfs_name_hash(line, strlen(line));
printf("hash returns %llu\n", (unsigned long long)result);
}
return 0;
}
/*
* xattrs work a lot like directories, this inserts an xattr item
* into the tree
*/
int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 objectid,
const char *name, u16 name_len,
const void *data, u16 data_len)
{
int ret = 0;
struct btrfs_dir_item *dir_item;
unsigned long name_ptr, data_ptr;
struct btrfs_key key, location;
struct btrfs_disk_key disk_key;
struct extent_buffer *leaf;
u32 data_size;
if (name_len + data_len > BTRFS_MAX_XATTR_SIZE(root->fs_info))
return -ENOSPC;
key.objectid = objectid;
key.type = BTRFS_XATTR_ITEM_KEY;
key.offset = btrfs_name_hash(name, name_len);
data_size = sizeof(*dir_item) + name_len + data_len;
dir_item = insert_with_overflow(trans, root, path, &key, data_size,
name, name_len);
if (IS_ERR(dir_item))
return PTR_ERR(dir_item);
memset(&location, 0, sizeof(location));
leaf = path->nodes[0];
btrfs_cpu_key_to_disk(&disk_key, &location);
btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
btrfs_set_dir_type(leaf, dir_item, BTRFS_FT_XATTR);
btrfs_set_dir_name_len(leaf, dir_item, name_len);
btrfs_set_dir_transid(leaf, dir_item, trans->transid);
btrfs_set_dir_data_len(leaf, dir_item, data_len);
name_ptr = (unsigned long)(dir_item + 1);
data_ptr = (unsigned long)((char *)name_ptr + name_len);
write_extent_buffer(leaf, name, name_ptr, name_len);
write_extent_buffer(leaf, data, data_ptr, data_len);
btrfs_mark_buffer_dirty(path->nodes[0]);
return ret;
}
struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
const char *name, u16 name_len,
int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
key.objectid = dir;
btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY);
key.offset = btrfs_name_hash(name, name_len);
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0)
return NULL;
return btrfs_match_dir_item_name(root, path, name, name_len);
}
/*
* insert a directory item in the tree, doing all the magic for
* both indexes. 'dir' indicates which objectid to insert it into,
* 'location' is the key to stuff into the directory item, 'type' is the
* type of the inode we're pointing to, and 'index' is the sequence number
* to use for the second index (if one is created).
* Will return 0 or -ENOMEM
*/
int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, const char *name, int name_len,
struct inode *dir, struct btrfs_key *location,
u8 type, u64 index)
{
int ret = 0;
int ret2 = 0;
struct btrfs_path *path;
struct btrfs_dir_item *dir_item;
struct extent_buffer *leaf;
unsigned long name_ptr;
struct btrfs_key key;
struct btrfs_disk_key disk_key;
u32 data_size;
key.objectid = btrfs_ino(dir);
btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
key.offset = btrfs_name_hash(name, name_len);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->leave_spinning = 1;
btrfs_cpu_key_to_disk(&disk_key, location);
data_size = sizeof(*dir_item) + name_len;
dir_item = insert_with_overflow(trans, root, path, &key, data_size,
name, name_len);
if (IS_ERR(dir_item)) {
ret = PTR_ERR(dir_item);
if (ret == -EEXIST)
goto second_insert;
goto out_free;
}
leaf = path->nodes[0];
btrfs_set_dir_item_key(leaf, dir_item, &disk_key);
btrfs_set_dir_type(leaf, dir_item, type);
btrfs_set_dir_data_len(leaf, dir_item, 0);
btrfs_set_dir_name_len(leaf, dir_item, name_len);
btrfs_set_dir_transid(leaf, dir_item, trans->transid);
name_ptr = (unsigned long)(dir_item + 1);
write_extent_buffer(leaf, name, name_ptr, name_len);
btrfs_mark_buffer_dirty(leaf);
second_insert:
/* FIXME, use some real flag for selecting the extra index */
if (root == root->fs_info->tree_root) {
ret = 0;
goto out_free;
}
btrfs_release_path(path);
ret2 = btrfs_insert_delayed_dir_index(trans, root, name, name_len, dir,
&disk_key, type, index);
out_free:
btrfs_free_path(path);
if (ret)
return ret;
if (ret2)
return ret2;
return 0;
}
