static int remove_extent_ref(struct btrfs_root *root, u64 bytenr,
u64 num_bytes, u64 parent, u64 root_objectid)
{
struct btrfs_trans_handle trans;
struct btrfs_extent_item *item;
struct btrfs_path *path;
struct btrfs_key key;
u64 refs;
int ret;
btrfs_init_dummy_trans(&trans);
key.objectid = bytenr;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
path = btrfs_alloc_path();
if (!path) {
test_msg("Couldn't allocate path\n");
return -ENOMEM;
}
path->leave_spinning = 1;
ret = btrfs_search_slot(&trans, root, &key, path, 0, 1);
if (ret) {
test_msg("Couldn't find extent ref\n");
btrfs_free_path(path);
return ret;
}
item = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_extent_item);
refs = btrfs_extent_refs(path->nodes[0], item);
btrfs_set_extent_refs(path->nodes[0], item, refs - 1);
btrfs_release_path(path);
key.objectid = bytenr;
if (parent) {
key.type = BTRFS_SHARED_BLOCK_REF_KEY;
key.offset = parent;
} else {
key.type = BTRFS_TREE_BLOCK_REF_KEY;
key.offset = root_objectid;
}
ret = btrfs_search_slot(&trans, root, &key, path, -1, 1);
if (ret) {
test_msg("Couldn't find backref %d\n", ret);
btrfs_free_path(path);
return ret;
}
btrfs_del_item(&trans, root, path);
btrfs_free_path(path);
return ret;
}
int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_root_item
*item)
{
struct btrfs_path *path;
struct extent_buffer *l;
int ret;
int slot;
unsigned long ptr;
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
if (ret < 0)
goto out;
BUG_ON(ret != 0);
l = path->nodes[0];
slot = path->slots[0];
ptr = btrfs_item_ptr_offset(l, slot);
write_extent_buffer(l, item, ptr, sizeof(*item));
btrfs_mark_buffer_dirty(path->nodes[0]);
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
return ret;
}
static int write_one_cache_group(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_block_group_cache *cache)
{
int ret;
int pending_ret;
struct btrfs_root *extent_root = root->fs_info->extent_root;
struct btrfs_block_group_item *bi;
struct btrfs_key ins;
ret = find_free_extent(trans, root, 0, 0, (u64)-1, &ins);
if (ret)
return ret;
ret = btrfs_search_slot(trans, root->fs_info->extent_root,
&cache->key, path, 0, 1);
BUG_ON(ret);
bi = btrfs_item_ptr(&path->nodes[0]->leaf, path->slots[0],
struct btrfs_block_group_item);
memcpy(bi, &cache->item, sizeof(*bi));
dirty_tree_block(trans, extent_root, path->nodes[0]);
btrfs_release_path(extent_root, path);
finish_current_insert(trans, root);
pending_ret = run_pending(trans, root);
if (ret)
return ret;
if (pending_ret)
return pending_ret;
return 0;
}
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 remove_extent_item(struct btrfs_root *root, u64 bytenr,
u64 num_bytes)
{
struct btrfs_trans_handle trans;
struct btrfs_key key;
struct btrfs_path *path;
int ret;
btrfs_init_dummy_trans(&trans);
key.objectid = bytenr;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
path = btrfs_alloc_path();
if (!path) {
test_msg("Couldn't allocate path\n");
return -ENOMEM;
}
path->leave_spinning = 1;
ret = btrfs_search_slot(&trans, root, &key, path, -1, 1);
if (ret) {
test_msg("Didn't find our key %d\n", ret);
btrfs_free_path(path);
return ret;
}
btrfs_del_item(&trans, root, path);
btrfs_free_path(path);
return 0;
}
/* drop the root item for 'key' from 'root' */
int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_key *key)
{
struct btrfs_path *path;
int ret;
u32 refs;
struct btrfs_root_item *ri;
struct extent_buffer *leaf;
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(trans, root, key, path, -1, 1);
if (ret < 0)
goto out;
BUG_ON(ret != 0);
leaf = path->nodes[0];
ri = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_item);
refs = btrfs_disk_root_refs(leaf, ri);
BUG_ON(refs != 0);
ret = btrfs_del_item(trans, root, path);
out:
btrfs_free_path(path);
return ret;
}
static int change_devices_uuid(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_path path;
struct btrfs_key key = {0, 0, 0};
int ret = 0;
btrfs_init_path(&path);
/* No transaction again */
ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
if (ret < 0)
goto out;
while (1) {
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
if (key.type != BTRFS_DEV_ITEM_KEY ||
key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
goto next;
ret = change_device_uuid(root, path.nodes[0], path.slots[0]);
if (ret < 0)
goto out;
next:
ret = btrfs_next_item(root, &path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
goto out;
}
}
out:
btrfs_release_path(&path);
return ret;
}
int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
{
struct btrfs_path *path;
int ret;
struct extent_buffer *l;
struct btrfs_key search_key;
struct btrfs_key found_key;
int slot;
path = btrfs_alloc_path();
BUG_ON(!path);
search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
search_key.type = -1;
search_key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
if (ret < 0)
goto error;
BUG_ON(ret == 0);
if (path->slots[0] > 0) {
slot = path->slots[0] - 1;
l = path->nodes[0];
btrfs_item_key_to_cpu(l, &found_key, slot);
*objectid = found_key.objectid;
} else {
*objectid = BTRFS_FIRST_FREE_OBJECTID;
}
ret = 0;
error:
btrfs_free_path(path);
return ret;
}
/*
* this makes the path point to (logical EXTENT_ITEM *)
* returns BTRFS_EXTENT_FLAG_DATA for data, BTRFS_EXTENT_FLAG_TREE_BLOCK for
* tree blocks and <0 on error.
*/
int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
struct btrfs_path *path, struct btrfs_key *found_key,
u64 *flags_ret)
{
int ret;
u64 flags;
u32 item_size;
struct extent_buffer *eb;
struct btrfs_extent_item *ei;
struct btrfs_key key;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.objectid = logical;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
if (ret < 0)
return ret;
ret = btrfs_previous_item(fs_info->extent_root, path,
0, BTRFS_EXTENT_ITEM_KEY);
if (ret < 0)
return ret;
btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]);
if (found_key->type != BTRFS_EXTENT_ITEM_KEY ||
found_key->objectid > logical ||
found_key->objectid + found_key->offset <= logical) {
pr_debug("logical %llu is not within any extent\n",
(unsigned long long)logical);
return -ENOENT;
}
eb = path->nodes[0];
item_size = btrfs_item_size_nr(eb, path->slots[0]);
BUG_ON(item_size < sizeof(*ei));
ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
flags = btrfs_extent_flags(eb, ei);
pr_debug("logical %llu is at position %llu within the extent (%llu "
"EXTENT_ITEM %llu) flags %#llx size %u\n",
(unsigned long long)logical,
(unsigned long long)(logical - found_key->objectid),
(unsigned long long)found_key->objectid,
(unsigned long long)found_key->offset,
(unsigned long long)flags, item_size);
WARN_ON(!flags_ret);
if (flags_ret) {
if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
*flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK;
else if (flags & BTRFS_EXTENT_FLAG_DATA)
*flags_ret = BTRFS_EXTENT_FLAG_DATA;
else
BUG_ON(1);
return 0;
}
return -EIO;
}
/*
* copy the data in 'item' into the btree
*/
int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_root_item
*item)
{
struct btrfs_path *path;
struct extent_buffer *l;
int ret;
int slot;
unsigned long ptr;
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
if (ret < 0)
goto out;
if (ret != 0) {
btrfs_print_leaf(root, path->nodes[0]);
printk(KERN_CRIT "unable to update root key %llu %u %llu\n",
(unsigned long long)key->objectid, key->type,
(unsigned long long)key->offset);
BUG_ON(1);
}
l = path->nodes[0];
slot = path->slots[0];
ptr = btrfs_item_ptr_offset(l, slot);
write_extent_buffer(l, item, ptr, sizeof(*item));
btrfs_mark_buffer_dirty(path->nodes[0]);
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;
}
int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_key *key)
{
struct btrfs_path *path;
int ret;
u32 refs;
struct btrfs_root_item *ri;
struct extent_buffer *leaf;
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(trans, root, key, path, -1, 1);
if (ret < 0)
goto out;
if (ret) {
btrfs_print_leaf(root, path->nodes[0]);
printk("failed to del %llu %u %llu\n",
(unsigned long long)key->objectid,
key->type,
(unsigned long long)key->offset);
}
BUG_ON(ret != 0);
leaf = path->nodes[0];
ri = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_item);
refs = btrfs_disk_root_refs(leaf, ri);
BUG_ON(refs != 0);
ret = btrfs_del_item(trans, root, path);
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
return ret;
}
static int __inode_info(u64 inum, u64 ioff, u8 key_type,
struct btrfs_root *fs_root, struct btrfs_path *path,
struct btrfs_key *found_key)
{
int ret;
struct btrfs_key key;
struct extent_buffer *eb;
key.type = key_type;
key.objectid = inum;
key.offset = ioff;
ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
if (ret < 0)
return ret;
eb = path->nodes[0];
if (ret && path->slots[0] >= btrfs_header_nritems(eb)) {
ret = btrfs_next_leaf(fs_root, path);
if (ret)
return ret;
eb = path->nodes[0];
}
btrfs_item_key_to_cpu(eb, found_key, path->slots[0]);
if (found_key->type != key.type || found_key->objectid != key.objectid)
return 1;
return 0;
}
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 change_extents_uuid(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root = fs_info->extent_root;
struct btrfs_path path;
struct btrfs_key key = {0, 0, 0};
int ret = 0;
btrfs_init_path(&path);
/*
* Here we don't use transaction as it will takes a lot of reserve
* space, and that will make a near-full btrfs unable to change uuid
*/
ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
if (ret < 0)
goto out;
while (1) {
struct btrfs_extent_item *ei;
struct extent_buffer *eb;
u64 flags;
u64 bytenr;
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
if (key.type != BTRFS_EXTENT_ITEM_KEY &&
key.type != BTRFS_METADATA_ITEM_KEY)
goto next;
ei = btrfs_item_ptr(path.nodes[0], path.slots[0],
struct btrfs_extent_item);
flags = btrfs_extent_flags(path.nodes[0], ei);
if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
goto next;
bytenr = key.objectid;
eb = read_tree_block(root, bytenr, root->nodesize, 0);
if (IS_ERR(eb)) {
error("failed to read tree block: %llu", bytenr);
ret = PTR_ERR(eb);
goto out;
}
ret = change_header_uuid(root, eb);
free_extent_buffer(eb);
if (ret < 0) {
error("failed to change uuid of tree block: %llu",
bytenr);
goto out;
}
next:
ret = btrfs_next_item(root, &path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
goto out;
}
}
out:
btrfs_release_path(&path);
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;
}
struct btrfs_free_space_info *
search_free_space_info(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_block_group_cache *block_group,
struct btrfs_path *path, int cow)
{
struct btrfs_root *root = fs_info->free_space_root;
struct btrfs_key key;
int ret;
key.objectid = block_group->key.objectid;
key.type = BTRFS_FREE_SPACE_INFO_KEY;
key.offset = block_group->key.offset;
ret = btrfs_search_slot(trans, root, &key, path, 0, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret != 0) {
btrfs_warn(fs_info, "missing free space info for %llu\n",
block_group->key.objectid);
ASSERT(0);
return ERR_PTR(-ENOENT);
}
return btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_free_space_info);
}
struct btrfs_inode_ref *
btrfs_lookup_inode_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
const char *name, int name_len,
u64 inode_objectid, u64 ref_objectid, int mod)
{
struct btrfs_key key;
struct btrfs_inode_ref *ref;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
int ret;
key.objectid = inode_objectid;
key.type = BTRFS_INODE_REF_KEY;
key.offset = ref_objectid;
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0)
return NULL;
if (!find_name_in_backref(path, name, name_len, &ref))
return NULL;
return ref;
}
struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
struct btrfs_key *location)
{
struct btrfs_root *root;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_path *path;
struct extent_buffer *l;
u64 generation;
u32 blocksize;
int ret = 0;
root = malloc(sizeof(*root));
if (!root)
return ERR_PTR(-ENOMEM);
memset(root, 0, sizeof(*root));
if (location->offset == (u64)-1) {
ret = find_and_setup_root(tree_root, fs_info,
location->objectid, root);
if (ret) {
free(root);
return ERR_PTR(ret);
}
goto insert;
}
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
root, fs_info, location->objectid);
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
if (ret != 0) {
if (ret > 0)
ret = -ENOENT;
goto out;
}
l = path->nodes[0];
read_extent_buffer(l, &root->root_item,
btrfs_item_ptr_offset(l, path->slots[0]),
sizeof(root->root_item));
memcpy(&root->root_key, location, sizeof(*location));
ret = 0;
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
if (ret) {
free(root);
return ERR_PTR(ret);
}
generation = btrfs_root_generation(&root->root_item);
blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
blocksize, generation);
BUG_ON(!root->node);
insert:
root->ref_cows = 1;
return root;
}
/*
* 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;
}
/* return -ENOENT for !found, < 0 for errors, or 0 if an item was found */
static int btrfs_uuid_tree_lookup(struct btrfs_root *uuid_root, u8 *uuid,
u8 type, u64 subid)
{
int ret;
struct btrfs_path *path = NULL;
struct extent_buffer *eb;
int slot;
u32 item_size;
unsigned long offset;
struct btrfs_key key;
if (WARN_ON_ONCE(!uuid_root)) {
ret = -ENOENT;
goto out;
}
path = btrfs_alloc_path();
if (!path) {
ret = -ENOMEM;
goto out;
}
btrfs_uuid_to_key(uuid, type, &key);
ret = btrfs_search_slot(NULL, uuid_root, &key, path, 0, 0);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = -ENOENT;
goto out;
}
eb = path->nodes[0];
slot = path->slots[0];
item_size = btrfs_item_size_nr(eb, slot);
offset = btrfs_item_ptr_offset(eb, slot);
ret = -ENOENT;
if (!IS_ALIGNED(item_size, sizeof(u64))) {
btrfs_warn(uuid_root->fs_info,
"uuid item with illegal size %lu!",
(unsigned long)item_size);
goto out;
}
while (item_size) {
__le64 data;
read_extent_buffer(eb, &data, offset, sizeof(data));
if (le64_to_cpu(data) == subid) {
ret = 0;
break;
}
offset += sizeof(data);
item_size -= sizeof(data);
}
out:
btrfs_free_path(path);
return ret;
}
static int map_one_extent(struct btrfs_fs_info *fs_info,
u64 *logical_ret, u64 *len_ret, int search_forward)
{
struct btrfs_path *path;
struct btrfs_key key;
u64 logical;
u64 len = 0;
int ret = 0;
BUG_ON(!logical_ret);
logical = *logical_ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = logical;
key.type = 0;
key.offset = 0;
ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path,
0, 0);
if (ret < 0)
goto out;
BUG_ON(ret == 0);
ret = 0;
again:
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if ((search_forward && key.objectid < logical) ||
(!search_forward && key.objectid > logical) ||
(key.type != BTRFS_EXTENT_ITEM_KEY &&
key.type != BTRFS_METADATA_ITEM_KEY)) {
if (!search_forward)
ret = btrfs_previous_extent_item(fs_info->extent_root,
path, 0);
else
ret = btrfs_next_extent_item(fs_info->extent_root,
path, 0);
if (ret)
goto out;
goto again;
}
logical = key.objectid;
if (key.type == BTRFS_METADATA_ITEM_KEY)
len = fs_info->nodesize;
else
len = key.offset;
out:
btrfs_free_path(path);
if (!ret) {
*logical_ret = logical;
if (len_ret)
*len_ret = len;
}
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;
}
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));
}
/*
* resolve an indirect backref in the form (root_id, key, level)
* to a logical address
*/
static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, u64 time_seq,
struct __prelim_ref *ref,
struct ulist *parents,
const u64 *extent_item_pos, u64 total_refs)
{
struct btrfs_root *root;
struct btrfs_key root_key;
struct extent_buffer *eb;
int ret = 0;
int root_level;
int level = ref->level;
root_key.objectid = ref->root_id;
root_key.type = BTRFS_ROOT_ITEM_KEY;
root_key.offset = (u64)-1;
root = btrfs_read_fs_root(fs_info, &root_key);
if (IS_ERR(root)) {
ret = PTR_ERR(root);
goto out;
}
root_level = btrfs_root_level(&root->root_item);
if (root_level + 1 == level)
goto out;
path->lowest_level = level;
ret = btrfs_search_slot(NULL, root, &ref->key_for_search, path, 0, 0);
pr_debug("search slot in root %llu (level %d, ref count %d) returned "
"%d for key (%llu %u %llu)\n",
ref->root_id, level, ref->count, ret,
ref->key_for_search.objectid, ref->key_for_search.type,
ref->key_for_search.offset);
if (ret < 0)
goto out;
eb = path->nodes[level];
while (!eb) {
if (!level) {
ret = 1;
WARN_ON(1);
goto out;
}
level--;
eb = path->nodes[level];
}
ret = add_all_parents(root, path, parents, ref, level, time_seq,
extent_item_pos, total_refs);
out:
path->lowest_level = 0;
btrfs_release_path(path);
return ret;
}
int btrfs_find_orphan_roots(struct btrfs_root *tree_root)
{
struct extent_buffer *leaf;
struct btrfs_path *path;
struct btrfs_key key;
int err = 0;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_ORPHAN_OBJECTID;
key.type = BTRFS_ORPHAN_ITEM_KEY;
key.offset = 0;
while (1) {
ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
if (ret < 0) {
err = ret;
break;
}
leaf = path->nodes[0];
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(tree_root, path);
if (ret < 0)
err = ret;
if (ret != 0)
break;
leaf = path->nodes[0];
}
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
btrfs_release_path(tree_root, path);
if (key.objectid != BTRFS_ORPHAN_OBJECTID ||
key.type != BTRFS_ORPHAN_ITEM_KEY)
break;
ret = btrfs_find_dead_roots(tree_root, key.offset);
if (ret) {
err = ret;
break;
}
key.offset++;
}
btrfs_free_path(path);
return err;
}
/*
* Find a free inode index for later btrfs_add_link().
* Currently just search from the largest dir_index and +1.
*/
static int btrfs_find_free_dir_index(struct btrfs_root *root, u64 dir_ino,
u64 *ret_ino)
{
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_key found_key;
u64 ret_val = 2;
int ret = 0;
if (!ret_ino)
return 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = dir_ino;
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
ret = 0;
if (path->slots[0] == 0) {
ret = btrfs_prev_leaf(root, path);
if (ret < 0)
goto out;
if (ret > 0) {
/*
* This shouldn't happen since there must be a leaf
* containing the DIR_ITEM.
* Can only happen when the previous leaf is corrupted.
*/
ret = -EIO;
goto out;
}
} else {
path->slots[0]--;
}
btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
if (found_key.objectid != dir_ino ||
found_key.type != BTRFS_DIR_INDEX_KEY)
goto out;
ret_val = found_key.offset + 1;
out:
btrfs_free_path(path);
if (ret == 0)
*ret_ino = ret_val;
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 dentry *btrfs_get_parent(struct dentry *child)
{
struct inode *dir = d_inode(child);
struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
struct btrfs_root *root = BTRFS_I(dir)->root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_root_ref *ref;
struct btrfs_key key;
struct btrfs_key found_key;
int ret;
path = btrfs_alloc_path();
if (!path)
return ERR_PTR(-ENOMEM);
if (btrfs_ino(BTRFS_I(dir)) == BTRFS_FIRST_FREE_OBJECTID) {
key.objectid = root->root_key.objectid;
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = (u64)-1;
root = fs_info->tree_root;
} else {
key.objectid = btrfs_ino(BTRFS_I(dir));
key.type = BTRFS_INODE_REF_KEY;
key.offset = (u64)-1;
}
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto fail;
BUG_ON(ret == 0); /* Key with offset of -1 found */
if (path->slots[0] == 0) {
ret = -ENOENT;
goto fail;
}
path->slots[0]--;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.objectid != key.objectid || found_key.type != key.type) {
ret = -ENOENT;
goto fail;
}
if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_root_ref);
key.objectid = btrfs_root_ref_dirid(leaf, ref);
} else {
