static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
u64 root_objectid, u32 generation)
{
struct btrfs_root *root;
struct inode *inode;
struct btrfs_key key;
key.objectid = root_objectid;
btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
key.offset = (u64)-1;
root = btrfs_read_fs_root_no_name(btrfs_sb(sb)->fs_info, &key);
if (IS_ERR(root))
return ERR_CAST(root);
key.objectid = objectid;
btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
key.offset = 0;
inode = btrfs_iget(sb, &key, root, NULL);
if (IS_ERR(inode))
return (void *)inode;
if (generation != inode->i_generation) {
iput(inode);
return ERR_PTR(-ESTALE);
}
return d_obtain_alias(inode);
}
static struct dentry *btrfs_get_parent(struct dentry *child)
{
struct inode *dir = child->d_inode;
struct btrfs_root *root = BTRFS_I(dir)->root;
struct btrfs_key key;
struct btrfs_path *path;
struct extent_buffer *leaf;
int slot;
u64 objectid;
int ret;
path = btrfs_alloc_path();
key.objectid = dir->i_ino;
btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0) {
/* Error */
btrfs_free_path(path);
return ERR_PTR(ret);
}
leaf = path->nodes[0];
slot = path->slots[0];
if (ret) {
/* btrfs_search_slot() returns the slot where we'd want to
insert a backref for parent inode #0xFFFFFFFFFFFFFFFF.
The _real_ backref, telling us what the parent inode
_actually_ is, will be in the slot _before_ the one
that btrfs_search_slot() returns. */
if (!slot) {
/* Unless there is _no_ key in the tree before... */
btrfs_free_path(path);
return ERR_PTR(-EIO);
}
slot--;
}
btrfs_item_key_to_cpu(leaf, &key, slot);
btrfs_free_path(path);
if (key.objectid != dir->i_ino || key.type != BTRFS_INODE_REF_KEY)
return ERR_PTR(-EINVAL);
objectid = key.offset;
/* If we are already at the root of a subvol, return the real root */
if (objectid == dir->i_ino)
return dget(dir->i_sb->s_root);
/* Build a new key for the inode item */
key.objectid = objectid;
btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
key.offset = 0;
return d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root, NULL));
}
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;
}
static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
u64 root_objectid, u32 generation,
int check_generation)
{
struct btrfs_fs_info *fs_info = btrfs_sb(sb);
struct btrfs_root *root;
struct inode *inode;
struct btrfs_key key;
int index;
int err = 0;
if (objectid < BTRFS_FIRST_FREE_OBJECTID)
return ERR_PTR(-ESTALE);
key.objectid = root_objectid;
btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
key.offset = (u64)-1;
index = srcu_read_lock(&fs_info->subvol_srcu);
root = btrfs_read_fs_root_no_name(fs_info, &key);
if (IS_ERR(root)) {
err = PTR_ERR(root);
goto fail;
}
if (btrfs_root_refs(&root->root_item) == 0) {
err = -ENOENT;
goto fail;
}
key.objectid = objectid;
btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
key.offset = 0;
inode = btrfs_iget(sb, &key, root, NULL);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto fail;
}
srcu_read_unlock(&fs_info->subvol_srcu, index);
if (check_generation && generation != inode->i_generation) {
iput(inode);
return ERR_PTR(-ESTALE);
}
return d_obtain_alias(inode);
fail:
srcu_read_unlock(&fs_info->subvol_srcu, index);
return ERR_PTR(err);
}
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);
}
static int add_directory_items(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
ino_t parent_inum, const char *name,
struct stat *st, int *dir_index_cnt)
{
int ret;
int name_len;
struct btrfs_key location;
u8 filetype = 0;
name_len = strlen(name);
location.objectid = objectid;
location.offset = 0;
btrfs_set_key_type(&location, BTRFS_INODE_ITEM_KEY);
if (S_ISDIR(st->st_mode))
filetype = BTRFS_FT_DIR;
if (S_ISREG(st->st_mode))
filetype = BTRFS_FT_REG_FILE;
if (S_ISLNK(st->st_mode))
filetype = BTRFS_FT_SYMLINK;
ret = btrfs_insert_dir_item(trans, root, name, name_len,
parent_inum, &location,
filetype, index_cnt);
*dir_index_cnt = index_cnt;
index_cnt++;
return ret;
}
int btrfs_del_orphan_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 offset)
{
struct btrfs_path *path;
struct btrfs_key key;
int ret = 0;
key.objectid = BTRFS_ORPHAN_OBJECTID;
btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
key.offset = offset;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret)
goto out;
ret = btrfs_del_item(trans, root, path);
out:
btrfs_free_path(path);
return ret;
}
static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
*root, u64 blocknr)
{
struct btrfs_path path;
int ret;
struct btrfs_key key;
struct btrfs_leaf *l;
struct btrfs_extent_item *item;
struct btrfs_key ins;
u32 refs;
find_free_extent(trans, root->fs_info->extent_root, 0, 0, (u64)-1,
&ins);
btrfs_init_path(&path);
key.objectid = blocknr;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
key.offset = 1;
ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, &path,
0, 1);
if (ret != 0)
BUG();
BUG_ON(ret != 0);
l = &path.nodes[0]->leaf;
item = btrfs_item_ptr(l, path.slots[0], struct btrfs_extent_item);
refs = btrfs_extent_refs(item);
btrfs_set_extent_refs(item, refs + 1);
BUG_ON(list_empty(&path.nodes[0]->dirty));
btrfs_release_path(root->fs_info->extent_root, &path);
finish_current_insert(trans, root->fs_info->extent_root);
run_pending(trans, root->fs_info->extent_root);
return 0;
}
static int finish_current_insert(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root)
{
struct btrfs_key ins;
struct btrfs_extent_item extent_item;
unsigned int i;
int ret;
u64 super_blocks_used;
struct btrfs_fs_info *info = extent_root->fs_info;
btrfs_set_extent_refs(&extent_item, 1);
btrfs_set_extent_owner(&extent_item, extent_root->root_key.objectid);
ins.offset = 1;
ins.flags = 0;
btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
for (i = 0; i < extent_root->fs_info->current_insert.flags; i++) {
ins.objectid = extent_root->fs_info->current_insert.objectid +
i;
super_blocks_used = btrfs_super_blocks_used(info->disk_super);
btrfs_set_super_blocks_used(info->disk_super,
super_blocks_used + 1);
ret = btrfs_insert_item(trans, extent_root, &ins, &extent_item,
sizeof(extent_item));
if (ret) {
btrfs_print_tree(extent_root, extent_root->node);
}
BUG_ON(ret);
}
extent_root->fs_info->current_insert.offset = 0;
return 0;
}
/*
* remove an extent from the root, returns 0 on success
*/
static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
*root, u64 blocknr, u64 num_blocks, int pin)
{
struct btrfs_path path;
struct btrfs_key key;
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_root *extent_root = info->extent_root;
int ret;
struct btrfs_extent_item *ei;
struct btrfs_key ins;
u32 refs;
BUG_ON(pin && num_blocks != 1);
key.objectid = blocknr;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
key.offset = num_blocks;
find_free_extent(trans, root, 0, 0, (u64)-1, &ins);
btrfs_init_path(&path);
ret = btrfs_search_slot(trans, extent_root, &key, &path, -1, 1);
if (ret) {
btrfs_print_tree(extent_root, extent_root->node);
printf("failed to find %llu\n",
(u64)key.objectid);
BUG();
}
ei = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0],
struct btrfs_extent_item);
BUG_ON(ei->refs == 0);
refs = btrfs_extent_refs(ei) - 1;
btrfs_set_extent_refs(ei, refs);
if (refs == 0) {
u64 super_blocks_used;
if (pin) {
int err;
unsigned long bl = blocknr;
radix_tree_preload(GFP_KERNEL);
err = radix_tree_insert(&info->pinned_radix,
blocknr, (void *)bl);
BUG_ON(err);
radix_tree_preload_end();
}
super_blocks_used = btrfs_super_blocks_used(info->disk_super);
btrfs_set_super_blocks_used(info->disk_super,
super_blocks_used - num_blocks);
ret = btrfs_del_item(trans, extent_root, &path);
if (!pin && extent_root->fs_info->last_insert.objectid >
blocknr)
extent_root->fs_info->last_insert.objectid = blocknr;
if (ret)
BUG();
ret = update_block_group(trans, root, blocknr, num_blocks, 0);
BUG_ON(ret);
}
btrfs_release_path(extent_root, &path);
finish_current_insert(trans, extent_root);
return ret;
}
int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
const char *name, int name_len,
u64 inode_objectid, u64 ref_objectid, u64 *index)
{
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_inode_ref *ref;
struct extent_buffer *leaf;
unsigned long ptr;
unsigned long item_start;
u32 item_size;
u32 sub_item_len;
int ret;
int del_len = name_len + sizeof(*ref);
key.objectid = inode_objectid;
key.offset = ref_objectid;
btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->leave_spinning = 1;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0) {
ret = -ENOENT;
goto out;
} else if (ret < 0) {
goto out;
}
if (!find_name_in_backref(path, name, name_len, &ref)) {
ret = -ENOENT;
goto out;
}
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
if (index)
*index = btrfs_inode_ref_index(leaf, ref);
if (del_len == item_size) {
ret = btrfs_del_item(trans, root, path);
goto out;
}
ptr = (unsigned long)ref;
sub_item_len = name_len + sizeof(*ref);
item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
item_size - (ptr + sub_item_len - item_start));
btrfs_truncate_item(trans, root, path,
item_size - sub_item_len, 1);
out:
btrfs_free_path(path);
return ret;
}
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;
}
/*
* new snapshots need to be created at a very specific time in the
* transaction commit. This does the actual creation
*/
static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_pending_snapshot *pending)
{
struct btrfs_key key;
struct btrfs_root_item *new_root_item;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *root = pending->root;
struct extent_buffer *tmp;
struct extent_buffer *old;
int ret;
u64 objectid;
new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
if (!new_root_item) {
ret = -ENOMEM;
goto fail;
}
ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid);
if (ret)
goto fail;
record_root_in_trans(trans, root);
btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
key.objectid = objectid;
/* record when the snapshot was created in key.offset */
key.offset = trans->transid;
btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
old = btrfs_lock_root_node(root);
btrfs_cow_block(trans, root, old, NULL, 0, &old);
btrfs_set_lock_blocking(old);
btrfs_copy_root(trans, root, old, &tmp, objectid);
btrfs_tree_unlock(old);
free_extent_buffer(old);
btrfs_set_root_node(new_root_item, tmp);
ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
new_root_item);
btrfs_tree_unlock(tmp);
free_extent_buffer(tmp);
if (ret)
goto fail;
key.offset = (u64)-1;
memcpy(&pending->root_key, &key, sizeof(key));
fail:
kfree(new_root_item);
btrfs_unreserve_metadata_space(root, 6);
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_read_block_groups(struct btrfs_root *root)
{
struct btrfs_path path;
int ret;
int err = 0;
struct btrfs_block_group_item *bi;
struct btrfs_block_group_cache *cache;
struct btrfs_key key;
struct btrfs_key found_key;
struct btrfs_leaf *leaf;
u64 group_size_blocks = BTRFS_BLOCK_GROUP_SIZE / root->blocksize;
root = root->fs_info->extent_root;
key.objectid = 0;
key.offset = group_size_blocks;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
btrfs_init_path(&path);
while(1) {
ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
&key, &path, 0, 0);
if (ret != 0) {
err = ret;
break;
}
leaf = &path.nodes[0]->leaf;
btrfs_disk_key_to_cpu(&found_key,
&leaf->items[path.slots[0]].key);
cache = malloc(sizeof(*cache));
if (!cache) {
err = -1;
break;
}
bi = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_block_group_item);
memcpy(&cache->item, bi, sizeof(*bi));
memcpy(&cache->key, &found_key, sizeof(found_key));
key.objectid = found_key.objectid + found_key.offset;
btrfs_release_path(root, &path);
ret = radix_tree_insert(&root->fs_info->block_group_radix,
found_key.objectid +
found_key.offset - 1, (void *)cache);
BUG_ON(ret);
if (key.objectid >=
btrfs_super_total_blocks(root->fs_info->disk_super))
break;
}
btrfs_release_path(root, &path);
return 0;
}
static struct btrfs_csum_item *
btrfs_lookup_csum(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, int cow)
{
int ret;
struct btrfs_key file_key;
struct btrfs_key found_key;
struct btrfs_csum_item *item;
struct extent_buffer *leaf;
u64 csum_offset = 0;
u16 csum_size =
btrfs_super_csum_size(root->fs_info->super_copy);
int csums_in_item;
file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
file_key.offset = bytenr;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_CSUM_KEY);
ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
if (ret < 0)
goto fail;
leaf = path->nodes[0];
if (ret > 0) {
ret = 1;
if (path->slots[0] == 0)
goto fail;
path->slots[0]--;
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (btrfs_key_type(&found_key) != BTRFS_EXTENT_CSUM_KEY)
goto fail;
csum_offset = (bytenr - found_key.offset) / root->sectorsize;
csums_in_item = btrfs_item_size_nr(leaf, path->slots[0]);
csums_in_item /= csum_size;
if (csum_offset >= csums_in_item) {
ret = -EFBIG;
goto fail;
}
}
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
item = (struct btrfs_csum_item *)((unsigned char *)item +
csum_offset * csum_size);
return item;
fail:
if (ret > 0)
ret = -ENOENT;
return ERR_PTR(ret);
}
int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 objectid,
u64 offset, int mod)
{
int ret;
struct btrfs_key file_key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
file_key.objectid = objectid;
file_key.offset = offset;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
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 btrfs_insert_inline_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
u64 offset, char *buffer, size_t size)
{
struct btrfs_key key;
struct btrfs_path *path;
struct extent_buffer *leaf;
unsigned long ptr;
struct btrfs_file_extent_item *ei;
u32 datasize;
int err = 0;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = objectid;
key.offset = offset;
btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
datasize = btrfs_file_extent_calc_inline_size(size);
ret = btrfs_insert_empty_item(trans, root, path, &key, datasize);
if (ret) {
err = ret;
goto fail;
}
leaf = path->nodes[0];
ei = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
btrfs_set_file_extent_generation(leaf, ei, trans->transid);
btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
btrfs_set_file_extent_ram_bytes(leaf, ei, size);
btrfs_set_file_extent_compression(leaf, ei, 0);
btrfs_set_file_extent_encryption(leaf, ei, 0);
btrfs_set_file_extent_other_encoding(leaf, ei, 0);
ptr = btrfs_file_extent_inline_start(ei) + offset - key.offset;
write_extent_buffer(leaf, buffer, ptr, size);
btrfs_mark_buffer_dirty(leaf);
fail:
btrfs_free_path(path);
return err;
}
int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 objectid, u64 pos,
u64 disk_offset, u64 disk_num_bytes,
u64 num_bytes, u64 offset, u64 ram_bytes,
u8 compression, u8 encryption, u16 other_encoding)
{
int ret = 0;
struct btrfs_file_extent_item *item;
struct btrfs_key file_key;
struct btrfs_path *path;
struct extent_buffer *leaf;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
file_key.objectid = objectid;
file_key.offset = pos;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
path->leave_spinning = 1;
ret = btrfs_insert_empty_item(trans, root, path, &file_key,
sizeof(*item));
if (ret < 0)
goto out;
BUG_ON(ret); /* Can't happen */
leaf = path->nodes[0];
item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
btrfs_set_file_extent_disk_bytenr(leaf, item, disk_offset);
btrfs_set_file_extent_disk_num_bytes(leaf, item, disk_num_bytes);
btrfs_set_file_extent_offset(leaf, item, offset);
btrfs_set_file_extent_num_bytes(leaf, item, num_bytes);
btrfs_set_file_extent_ram_bytes(leaf, item, ram_bytes);
btrfs_set_file_extent_generation(leaf, item, trans->transid);
btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
btrfs_set_file_extent_compression(leaf, item, compression);
btrfs_set_file_extent_encryption(leaf, item, encryption);
btrfs_set_file_extent_other_encoding(leaf, item, other_encoding);
btrfs_mark_buffer_dirty(leaf);
out:
btrfs_free_path(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,
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;
BUG_ON(name_len + data_len > BTRFS_MAX_XATTR_SIZE(root));
key.objectid = objectid;
btrfs_set_key_type(&key, 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;
}
static struct btrfs_csum_item *
btrfs_lookup_csum(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, int cow)
{
int ret;
struct btrfs_key file_key;
struct btrfs_key found_key;
struct btrfs_csum_item *item;
struct extent_buffer *leaf;
u64 csum_offset = 0;
u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
int csums_in_item;
file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
file_key.offset = bytenr;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_CSUM_KEY);
ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
if (ret < 0)
goto fail;
leaf = path->nodes[0];
if (ret > 0) {
ret = 1;
if (path->slots[0] == 0)
goto fail;
path->slots[0]--;
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (btrfs_key_type(&found_key) != BTRFS_EXTENT_CSUM_KEY)
goto fail;
csum_offset = (bytenr - found_key.offset) >>
root->fs_info->sb->s_blocksize_bits;
csums_in_item = btrfs_item_size_nr(leaf, path->slots[0]);
csums_in_item /= csum_size;
if (csum_offset == csums_in_item) {
ret = -EFBIG;
goto fail;
} else if (csum_offset > csums_in_item) {
goto fail;
}
}
int btrfs_insert_orphan_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 offset)
{
struct btrfs_path *path;
struct btrfs_key key;
int ret = 0;
key.objectid = BTRFS_ORPHAN_OBJECTID;
btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
key.offset = offset;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
btrfs_free_path(path);
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);
}
static int add_inode_items(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct stat *st, char *name,
u64 self_objectid, ino_t parent_inum,
int dir_index_cnt, struct btrfs_inode_item *inode_ret)
{
int ret;
struct btrfs_key inode_key;
struct btrfs_inode_item btrfs_inode;
u64 objectid;
u64 inode_size = 0;
int name_len;
name_len = strlen(name);
fill_inode_item(trans, root, &btrfs_inode, st);
objectid = self_objectid;
if (S_ISDIR(st->st_mode)) {
inode_size = calculate_dir_inode_size(name);
btrfs_set_stack_inode_size(&btrfs_inode, inode_size);
}
inode_key.objectid = objectid;
inode_key.offset = 0;
btrfs_set_key_type(&inode_key, BTRFS_INODE_ITEM_KEY);
ret = btrfs_insert_inode(trans, root, objectid, &btrfs_inode);
if (ret)
goto fail;
ret = btrfs_insert_inode_ref(trans, root, name, name_len,
objectid, parent_inum, dir_index_cnt);
if (ret)
goto fail;
*inode_ret = btrfs_inode;
fail:
return ret;
}
int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
const char *name, int name_len,
u64 inode_objectid, u64 ref_objectid, u64 index)
{
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_inode_ref *ref;
unsigned long ptr;
int ret;
int ins_len = name_len + sizeof(*ref);
key.objectid = inode_objectid;
key.offset = ref_objectid;
btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_insert_empty_item(trans, root, path, &key,
ins_len);
if (ret == -EEXIST) {
u32 old_size;
if (find_name_in_backref(path, name, name_len, &ref))
goto out;
old_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
ret = btrfs_extend_item(trans, root, path, ins_len);
BUG_ON(ret);
ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_inode_ref);
ref = (struct btrfs_inode_ref *)((unsigned long)ref + old_size);
btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
btrfs_set_inode_ref_index(path->nodes[0], ref, index);
ptr = (unsigned long)(ref + 1);
ret = 0;
} else if (ret < 0) {
static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
*root, u64 blocknr, u32 *refs)
{
struct btrfs_path path;
int ret;
struct btrfs_key key;
struct btrfs_leaf *l;
struct btrfs_extent_item *item;
btrfs_init_path(&path);
key.objectid = blocknr;
key.offset = 1;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, &path,
0, 0);
if (ret != 0)
BUG();
l = &path.nodes[0]->leaf;
item = btrfs_item_ptr(l, path.slots[0], struct btrfs_extent_item);
*refs = btrfs_extent_refs(item);
btrfs_release_path(root->fs_info->extent_root, &path);
return 0;
}
/*
* lookup a directory item based on index. 'dir' is the objectid
* we're searching in, and 'mod' tells us if you plan on deleting the
* item (use mod < 0) or changing the options (use mod > 0)
*
* The name is used to make sure the index really points to the name you were
* looking for.
*/
struct btrfs_dir_item *
btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
u64 objectid, const 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;
btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
key.offset = objectid;
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0)
return ERR_PTR(-ENOENT);
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;
}
ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
struct btrfs_key key, found_key;
struct inode *inode = dentry->d_inode;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_dir_item *di;
int ret = 0, slot;
size_t total_size = 0, size_left = size;
unsigned long name_ptr;
size_t name_len;
/*
* ok we want all objects associated with this id.
* NOTE: we set key.offset = 0; because we want to start with the
* first xattr that we find and walk forward
*/
key.objectid = btrfs_ino(inode);
btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY);
key.offset = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 2;
/* search for our xattrs */
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto err;
while (1) {
leaf = path->nodes[0];
slot = path->slots[0];
/* this is where we start walking through the path */
if (slot >= btrfs_header_nritems(leaf)) {
/*
* if we've reached the last slot in this leaf we need
* to go to the next leaf and reset everything
*/
ret = btrfs_next_leaf(root, path);
if (ret < 0)
goto err;
else if (ret > 0)
break;
continue;
}
btrfs_item_key_to_cpu(leaf, &found_key, slot);
/* check to make sure this item is what we want */
if (found_key.objectid != key.objectid)
break;
if (btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY)
break;
di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
if (verify_dir_item(root, leaf, di))
continue;
name_len = btrfs_dir_name_len(leaf, di);
total_size += name_len + 1;
/* we are just looking for how big our buffer needs to be */
if (!size)
goto next;
if (!buffer || (name_len + 1) > size_left) {
ret = -ERANGE;
goto err;
}
name_ptr = (unsigned long)(di + 1);
read_extent_buffer(leaf, buffer, name_ptr, name_len);
buffer[name_len] = '\0';
size_left -= name_len + 1;
buffer += name_len + 1;
next:
path->slots[0]++;
}
ret = total_size;
err:
btrfs_free_path(path);
return ret;
}
