blob: 0c8152a336b171ab5981f79db6a5dc530fd04fa5 [file] [log] [blame]
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
#include "transaction.h"
#include "crc32c.h"
#include "volumes.h"
#include "free-space-cache.h"
#include "math.h"
#include "utils.h"
#define PENDING_EXTENT_INSERT 0
#define PENDING_EXTENT_DELETE 1
#define PENDING_BACKREF_UPDATE 2
struct pending_extent_op {
int type;
u64 bytenr;
u64 num_bytes;
u64 flags;
struct btrfs_disk_key key;
int level;
};
static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 root_objectid, u64 generation,
u64 flags, struct btrfs_disk_key *key,
int level, struct btrfs_key *ins);
static int __free_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner_objectid,
u64 owner_offset, int refs_to_drop);
static int finish_current_insert(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root);
static int del_pending_extents(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root);
static struct btrfs_block_group_cache *
btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group_cache
*hint, u64 search_start, int data, int owner);
static int remove_sb_from_cache(struct btrfs_root *root,
struct btrfs_block_group_cache *cache)
{
u64 bytenr;
u64 *logical;
int stripe_len;
int i, nr, ret;
struct extent_io_tree *free_space_cache;
free_space_cache = &root->fs_info->free_space_cache;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
cache->key.objectid, bytenr, 0,
&logical, &nr, &stripe_len);
BUG_ON(ret);
while (nr--) {
clear_extent_dirty(free_space_cache, logical[nr],
logical[nr] + stripe_len - 1, GFP_NOFS);
}
kfree(logical);
}
return 0;
}
static int cache_block_group(struct btrfs_root *root,
struct btrfs_block_group_cache *block_group)
{
struct btrfs_path *path;
int ret;
struct btrfs_key key;
struct extent_buffer *leaf;
struct extent_io_tree *free_space_cache;
int slot;
u64 last;
u64 hole_size;
if (!block_group)
return 0;
root = root->fs_info->extent_root;
free_space_cache = &root->fs_info->free_space_cache;
if (block_group->cached)
return 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 2;
last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
key.objectid = last;
key.offset = 0;
key.type = 0;
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];
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret < 0)
goto err;
if (ret == 0) {
continue;
} else {
break;
}
}
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.objectid < block_group->key.objectid) {
goto next;
}
if (key.objectid >= block_group->key.objectid +
block_group->key.offset) {
break;
}
if (key.type == BTRFS_EXTENT_ITEM_KEY ||
key.type == BTRFS_METADATA_ITEM_KEY) {
if (key.objectid > last) {
hole_size = key.objectid - last;
set_extent_dirty(free_space_cache, last,
last + hole_size - 1,
GFP_NOFS);
}
if (key.type == BTRFS_METADATA_ITEM_KEY)
last = key.objectid + root->leafsize;
else
last = key.objectid + key.offset;
}
next:
path->slots[0]++;
}
if (block_group->key.objectid +
block_group->key.offset > last) {
hole_size = block_group->key.objectid +
block_group->key.offset - last;
set_extent_dirty(free_space_cache, last,
last + hole_size - 1, GFP_NOFS);
}
remove_sb_from_cache(root, block_group);
block_group->cached = 1;
err:
btrfs_free_path(path);
return 0;
}
struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
btrfs_fs_info *info,
u64 bytenr)
{
struct extent_io_tree *block_group_cache;
struct btrfs_block_group_cache *block_group = NULL;
u64 ptr;
u64 start;
u64 end;
int ret;
bytenr = max_t(u64, bytenr,
BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
block_group_cache = &info->block_group_cache;
ret = find_first_extent_bit(block_group_cache,
bytenr, &start, &end,
BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
BLOCK_GROUP_SYSTEM);
if (ret) {
return NULL;
}
ret = get_state_private(block_group_cache, start, &ptr);
if (ret)
return NULL;
block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
return block_group;
}
struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
btrfs_fs_info *info,
u64 bytenr)
{
struct extent_io_tree *block_group_cache;
struct btrfs_block_group_cache *block_group = NULL;
u64 ptr;
u64 start;
u64 end;
int ret;
block_group_cache = &info->block_group_cache;
ret = find_first_extent_bit(block_group_cache,
bytenr, &start, &end,
BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
BLOCK_GROUP_SYSTEM);
if (ret) {
return NULL;
}
ret = get_state_private(block_group_cache, start, &ptr);
if (ret)
return NULL;
block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
if (block_group->key.objectid <= bytenr && bytenr <
block_group->key.objectid + block_group->key.offset)
return block_group;
return NULL;
}
static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
{
return (cache->flags & bits) == bits;
}
static int noinline find_search_start(struct btrfs_root *root,
struct btrfs_block_group_cache **cache_ret,
u64 *start_ret, int num, int data)
{
int ret;
struct btrfs_block_group_cache *cache = *cache_ret;
u64 last = *start_ret;
u64 start = 0;
u64 end = 0;
u64 search_start = *start_ret;
int wrapped = 0;
if (!cache)
goto out;
again:
ret = cache_block_group(root, cache);
if (ret)
goto out;
last = max(search_start, cache->key.objectid);
if (cache->ro || !block_group_bits(cache, data))
goto new_group;
while(1) {
ret = find_first_extent_bit(&root->fs_info->free_space_cache,
last, &start, &end, EXTENT_DIRTY);
if (ret) {
goto new_group;
}
start = max(last, start);
last = end + 1;
if (last - start < num) {
continue;
}
if (start + num > cache->key.objectid + cache->key.offset) {
goto new_group;
}
*start_ret = start;
return 0;
}
out:
*start_ret = last;
cache = btrfs_lookup_block_group(root->fs_info, search_start);
if (!cache) {
printk("Unable to find block group for %llu\n",
(unsigned long long)search_start);
WARN_ON(1);
}
return -ENOSPC;
new_group:
last = cache->key.objectid + cache->key.offset;
wrapped:
cache = btrfs_lookup_first_block_group(root->fs_info, last);
if (!cache) {
if (!wrapped) {
wrapped = 1;
last = search_start;
goto wrapped;
}
goto out;
}
*cache_ret = cache;
goto again;
}
static int block_group_state_bits(u64 flags)
{
int bits = 0;
if (flags & BTRFS_BLOCK_GROUP_DATA)
bits |= BLOCK_GROUP_DATA;
if (flags & BTRFS_BLOCK_GROUP_METADATA)
bits |= BLOCK_GROUP_METADATA;
if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
bits |= BLOCK_GROUP_SYSTEM;
return bits;
}
static struct btrfs_block_group_cache *
btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group_cache
*hint, u64 search_start, int data, int owner)
{
struct btrfs_block_group_cache *cache;
struct extent_io_tree *block_group_cache;
struct btrfs_block_group_cache *found_group = NULL;
struct btrfs_fs_info *info = root->fs_info;
u64 used;
u64 last = 0;
u64 hint_last;
u64 start;
u64 end;
u64 free_check;
u64 ptr;
int bit;
int ret;
int full_search = 0;
int factor = 10;
block_group_cache = &info->block_group_cache;
if (!owner)
factor = 10;
bit = block_group_state_bits(data);
if (search_start) {
struct btrfs_block_group_cache *shint;
shint = btrfs_lookup_block_group(info, search_start);
if (shint && !shint->ro && block_group_bits(shint, data)) {
used = btrfs_block_group_used(&shint->item);
if (used + shint->pinned <
div_factor(shint->key.offset, factor)) {
return shint;
}
}
}
if (hint && !hint->ro && block_group_bits(hint, data)) {
used = btrfs_block_group_used(&hint->item);
if (used + hint->pinned <
div_factor(hint->key.offset, factor)) {
return hint;
}
last = hint->key.objectid + hint->key.offset;
hint_last = last;
} else {
if (hint)
hint_last = max(hint->key.objectid, search_start);
else
hint_last = search_start;
last = hint_last;
}
again:
while(1) {
ret = find_first_extent_bit(block_group_cache, last,
&start, &end, bit);
if (ret)
break;
ret = get_state_private(block_group_cache, start, &ptr);
if (ret)
break;
cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
last = cache->key.objectid + cache->key.offset;
used = btrfs_block_group_used(&cache->item);
if (!cache->ro && block_group_bits(cache, data)) {
if (full_search)
free_check = cache->key.offset;
else
free_check = div_factor(cache->key.offset,
factor);
if (used + cache->pinned < free_check) {
found_group = cache;
goto found;
}
}
cond_resched();
}
if (!full_search) {
last = search_start;
full_search = 1;
goto again;
}
found:
return found_group;
}
/*
* Back reference rules. Back refs have three main goals:
*
* 1) differentiate between all holders of references to an extent so that
* when a reference is dropped we can make sure it was a valid reference
* before freeing the extent.
*
* 2) Provide enough information to quickly find the holders of an extent
* if we notice a given block is corrupted or bad.
*
* 3) Make it easy to migrate blocks for FS shrinking or storage pool
* maintenance. This is actually the same as #2, but with a slightly
* different use case.
*
* There are two kinds of back refs. The implicit back refs is optimized
* for pointers in non-shared tree blocks. For a given pointer in a block,
* back refs of this kind provide information about the block's owner tree
* and the pointer's key. These information allow us to find the block by
* b-tree searching. The full back refs is for pointers in tree blocks not
* referenced by their owner trees. The location of tree block is recorded
* in the back refs. Actually the full back refs is generic, and can be
* used in all cases the implicit back refs is used. The major shortcoming
* of the full back refs is its overhead. Every time a tree block gets
* COWed, we have to update back refs entry for all pointers in it.
*
* For a newly allocated tree block, we use implicit back refs for
* pointers in it. This means most tree related operations only involve
* implicit back refs. For a tree block created in old transaction, the
* only way to drop a reference to it is COW it. So we can detect the
* event that tree block loses its owner tree's reference and do the
* back refs conversion.
*
* When a tree block is COW'd through a tree, there are four cases:
*
* The reference count of the block is one and the tree is the block's
* owner tree. Nothing to do in this case.
*
* The reference count of the block is one and the tree is not the
* block's owner tree. In this case, full back refs is used for pointers
* in the block. Remove these full back refs, add implicit back refs for
* every pointers in the new block.
*
* The reference count of the block is greater than one and the tree is
* the block's owner tree. In this case, implicit back refs is used for
* pointers in the block. Add full back refs for every pointers in the
* block, increase lower level extents' reference counts. The original
* implicit back refs are entailed to the new block.
*
* The reference count of the block is greater than one and the tree is
* not the block's owner tree. Add implicit back refs for every pointer in
* the new block, increase lower level extents' reference count.
*
* Back Reference Key composing:
*
* The key objectid corresponds to the first byte in the extent,
* The key type is used to differentiate between types of back refs.
* There are different meanings of the key offset for different types
* of back refs.
*
* File extents can be referenced by:
*
* - multiple snapshots, subvolumes, or different generations in one subvol
* - different files inside a single subvolume
* - different offsets inside a file (bookend extents in file.c)
*
* The extent ref structure for the implicit back refs has fields for:
*
* - Objectid of the subvolume root
* - objectid of the file holding the reference
* - original offset in the file
* - how many bookend extents
*
* The key offset for the implicit back refs is hash of the first
* three fields.
*
* The extent ref structure for the full back refs has field for:
*
* - number of pointers in the tree leaf
*
* The key offset for the implicit back refs is the first byte of
* the tree leaf
*
* When a file extent is allocated, The implicit back refs is used.
* the fields are filled in:
*
* (root_key.objectid, inode objectid, offset in file, 1)
*
* When a file extent is removed file truncation, we find the
* corresponding implicit back refs and check the following fields:
*
* (btrfs_header_owner(leaf), inode objectid, offset in file)
*
* Btree extents can be referenced by:
*
* - Different subvolumes
*
* Both the implicit back refs and the full back refs for tree blocks
* only consist of key. The key offset for the implicit back refs is
* objectid of block's owner tree. The key offset for the full back refs
* is the first byte of parent block.
*
* When implicit back refs is used, information about the lowest key and
* level of the tree block are required. These information are stored in
* tree block info structure.
*/
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
static int convert_extent_item_v0(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 owner, u32 extra_size)
{
struct btrfs_extent_item *item;
struct btrfs_extent_item_v0 *ei0;
struct btrfs_extent_ref_v0 *ref0;
struct btrfs_tree_block_info *bi;
struct extent_buffer *leaf;
struct btrfs_key key;
struct btrfs_key found_key;
u32 new_size = sizeof(*item);
u64 refs;
int ret;
leaf = path->nodes[0];
BUG_ON(btrfs_item_size_nr(leaf, path->slots[0]) != sizeof(*ei0));
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
ei0 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_item_v0);
refs = btrfs_extent_refs_v0(leaf, ei0);
if (owner == (u64)-1) {
while (1) {
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret < 0)
return ret;
BUG_ON(ret > 0);
leaf = path->nodes[0];
}
btrfs_item_key_to_cpu(leaf, &found_key,
path->slots[0]);
BUG_ON(key.objectid != found_key.objectid);
if (found_key.type != BTRFS_EXTENT_REF_V0_KEY) {
path->slots[0]++;
continue;
}
ref0 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_ref_v0);
owner = btrfs_ref_objectid_v0(leaf, ref0);
break;
}
}
btrfs_release_path(path);
if (owner < BTRFS_FIRST_FREE_OBJECTID)
new_size += sizeof(*bi);
new_size -= sizeof(*ei0);
ret = btrfs_search_slot(trans, root, &key, path, new_size, 1);
if (ret < 0)
return ret;
BUG_ON(ret);
ret = btrfs_extend_item(trans, root, path, new_size);
BUG_ON(ret);
leaf = path->nodes[0];
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
btrfs_set_extent_refs(leaf, item, refs);
/* FIXME: get real generation */
btrfs_set_extent_generation(leaf, item, 0);
if (owner < BTRFS_FIRST_FREE_OBJECTID) {
btrfs_set_extent_flags(leaf, item,
BTRFS_EXTENT_FLAG_TREE_BLOCK |
BTRFS_BLOCK_FLAG_FULL_BACKREF);
bi = (struct btrfs_tree_block_info *)(item + 1);
/* FIXME: get first key of the block */
memset_extent_buffer(leaf, 0, (unsigned long)bi, sizeof(*bi));
btrfs_set_tree_block_level(leaf, bi, (int)owner);
} else {
btrfs_set_extent_flags(leaf, item, BTRFS_EXTENT_FLAG_DATA);
}
btrfs_mark_buffer_dirty(leaf);
return 0;
}
#endif
static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset)
{
u32 high_crc = ~(u32)0;
u32 low_crc = ~(u32)0;
__le64 lenum;
lenum = cpu_to_le64(root_objectid);
high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
lenum = cpu_to_le64(owner);
low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
lenum = cpu_to_le64(offset);
low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
return ((u64)high_crc << 31) ^ (u64)low_crc;
}
static u64 hash_extent_data_ref_item(struct extent_buffer *leaf,
struct btrfs_extent_data_ref *ref)
{
return hash_extent_data_ref(btrfs_extent_data_ref_root(leaf, ref),
btrfs_extent_data_ref_objectid(leaf, ref),
btrfs_extent_data_ref_offset(leaf, ref));
}
static int match_extent_data_ref(struct extent_buffer *leaf,
struct btrfs_extent_data_ref *ref,
u64 root_objectid, u64 owner, u64 offset)
{
if (btrfs_extent_data_ref_root(leaf, ref) != root_objectid ||
btrfs_extent_data_ref_objectid(leaf, ref) != owner ||
btrfs_extent_data_ref_offset(leaf, ref) != offset)
return 0;
return 1;
}
static noinline int lookup_extent_data_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, u64 parent,
u64 root_objectid,
u64 owner, u64 offset)
{
struct btrfs_key key;
struct btrfs_extent_data_ref *ref;
struct extent_buffer *leaf;
u32 nritems;
int ret;
int recow;
int err = -ENOENT;
key.objectid = bytenr;
if (parent) {
key.type = BTRFS_SHARED_DATA_REF_KEY;
key.offset = parent;
} else {
key.type = BTRFS_EXTENT_DATA_REF_KEY;
key.offset = hash_extent_data_ref(root_objectid,
owner, offset);
}
again:
recow = 0;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0) {
err = ret;
goto fail;
}
if (parent) {
if (!ret)
return 0;
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
key.type = BTRFS_EXTENT_REF_V0_KEY;
btrfs_release_path(path);
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0) {
err = ret;
goto fail;
}
if (!ret)
return 0;
#endif
goto fail;
}
leaf = path->nodes[0];
nritems = btrfs_header_nritems(leaf);
while (1) {
if (path->slots[0] >= nritems) {
ret = btrfs_next_leaf(root, path);
if (ret < 0)
err = ret;
if (ret)
goto fail;
leaf = path->nodes[0];
nritems = btrfs_header_nritems(leaf);
recow = 1;
}
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.objectid != bytenr ||
key.type != BTRFS_EXTENT_DATA_REF_KEY)
goto fail;
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_data_ref);
if (match_extent_data_ref(leaf, ref, root_objectid,
owner, offset)) {
if (recow) {
btrfs_release_path(path);
goto again;
}
err = 0;
break;
}
path->slots[0]++;
}
fail:
return err;
}
static noinline int insert_extent_data_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, u64 parent,
u64 root_objectid, u64 owner,
u64 offset, int refs_to_add)
{
struct btrfs_key key;
struct extent_buffer *leaf;
u32 size;
u32 num_refs;
int ret;
key.objectid = bytenr;
if (parent) {
key.type = BTRFS_SHARED_DATA_REF_KEY;
key.offset = parent;
size = sizeof(struct btrfs_shared_data_ref);
} else {
key.type = BTRFS_EXTENT_DATA_REF_KEY;
key.offset = hash_extent_data_ref(root_objectid,
owner, offset);
size = sizeof(struct btrfs_extent_data_ref);
}
ret = btrfs_insert_empty_item(trans, root, path, &key, size);
if (ret && ret != -EEXIST)
goto fail;
leaf = path->nodes[0];
if (parent) {
struct btrfs_shared_data_ref *ref;
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_shared_data_ref);
if (ret == 0) {
btrfs_set_shared_data_ref_count(leaf, ref, refs_to_add);
} else {
num_refs = btrfs_shared_data_ref_count(leaf, ref);
num_refs += refs_to_add;
btrfs_set_shared_data_ref_count(leaf, ref, num_refs);
}
} else {
struct btrfs_extent_data_ref *ref;
while (ret == -EEXIST) {
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_data_ref);
if (match_extent_data_ref(leaf, ref, root_objectid,
owner, offset))
break;
btrfs_release_path(path);
key.offset++;
ret = btrfs_insert_empty_item(trans, root, path, &key,
size);
if (ret && ret != -EEXIST)
goto fail;
leaf = path->nodes[0];
}
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_data_ref);
if (ret == 0) {
btrfs_set_extent_data_ref_root(leaf, ref,
root_objectid);
btrfs_set_extent_data_ref_objectid(leaf, ref, owner);
btrfs_set_extent_data_ref_offset(leaf, ref, offset);
btrfs_set_extent_data_ref_count(leaf, ref, refs_to_add);
} else {
num_refs = btrfs_extent_data_ref_count(leaf, ref);
num_refs += refs_to_add;
btrfs_set_extent_data_ref_count(leaf, ref, num_refs);
}
}
btrfs_mark_buffer_dirty(leaf);
ret = 0;
fail:
btrfs_release_path(path);
return ret;
}
static noinline int remove_extent_data_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
int refs_to_drop)
{
struct btrfs_key key;
struct btrfs_extent_data_ref *ref1 = NULL;
struct btrfs_shared_data_ref *ref2 = NULL;
struct extent_buffer *leaf;
u32 num_refs = 0;
int ret = 0;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
ref1 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_data_ref);
num_refs = btrfs_extent_data_ref_count(leaf, ref1);
} else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
ref2 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_shared_data_ref);
num_refs = btrfs_shared_data_ref_count(leaf, ref2);
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
} else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
struct btrfs_extent_ref_v0 *ref0;
ref0 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_ref_v0);
num_refs = btrfs_ref_count_v0(leaf, ref0);
#endif
} else {
BUG();
}
BUG_ON(num_refs < refs_to_drop);
num_refs -= refs_to_drop;
if (num_refs == 0) {
ret = btrfs_del_item(trans, root, path);
} else {
if (key.type == BTRFS_EXTENT_DATA_REF_KEY)
btrfs_set_extent_data_ref_count(leaf, ref1, num_refs);
else if (key.type == BTRFS_SHARED_DATA_REF_KEY)
btrfs_set_shared_data_ref_count(leaf, ref2, num_refs);
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
else {
struct btrfs_extent_ref_v0 *ref0;
ref0 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_ref_v0);
btrfs_set_ref_count_v0(leaf, ref0, num_refs);
}
#endif
btrfs_mark_buffer_dirty(leaf);
}
return ret;
}
static noinline u32 extent_data_ref_count(struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_extent_inline_ref *iref)
{
struct btrfs_key key;
struct extent_buffer *leaf;
struct btrfs_extent_data_ref *ref1;
struct btrfs_shared_data_ref *ref2;
u32 num_refs = 0;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (iref) {
if (btrfs_extent_inline_ref_type(leaf, iref) ==
BTRFS_EXTENT_DATA_REF_KEY) {
ref1 = (struct btrfs_extent_data_ref *)(&iref->offset);
num_refs = btrfs_extent_data_ref_count(leaf, ref1);
} else {
ref2 = (struct btrfs_shared_data_ref *)(iref + 1);
num_refs = btrfs_shared_data_ref_count(leaf, ref2);
}
} else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
ref1 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_data_ref);
num_refs = btrfs_extent_data_ref_count(leaf, ref1);
} else if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
ref2 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_shared_data_ref);
num_refs = btrfs_shared_data_ref_count(leaf, ref2);
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
} else if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
struct btrfs_extent_ref_v0 *ref0;
ref0 = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_ref_v0);
num_refs = btrfs_ref_count_v0(leaf, ref0);
#endif
} else {
BUG();
}
return num_refs;
}
static noinline int lookup_tree_block_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, u64 parent,
u64 root_objectid)
{
struct btrfs_key key;
int ret;
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 > 0)
ret = -ENOENT;
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
if (ret == -ENOENT && parent) {
btrfs_release_path(path);
key.type = BTRFS_EXTENT_REF_V0_KEY;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0)
ret = -ENOENT;
}
#endif
return ret;
}
static noinline int insert_tree_block_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, u64 parent,
u64 root_objectid)
{
struct btrfs_key key;
int ret;
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_insert_empty_item(trans, root, path, &key, 0);
btrfs_release_path(path);
return ret;
}
static inline int extent_ref_type(u64 parent, u64 owner)
{
int type;
if (owner < BTRFS_FIRST_FREE_OBJECTID) {
if (parent > 0)
type = BTRFS_SHARED_BLOCK_REF_KEY;
else
type = BTRFS_TREE_BLOCK_REF_KEY;
} else {
if (parent > 0)
type = BTRFS_SHARED_DATA_REF_KEY;
else
type = BTRFS_EXTENT_DATA_REF_KEY;
}
return type;
}
static int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_extent_inline_ref **ref_ret,
u64 bytenr, u64 num_bytes,
u64 parent, u64 root_objectid,
u64 owner, u64 offset, int insert)
{
struct btrfs_key key;
struct extent_buffer *leaf;
struct btrfs_extent_item *ei;
struct btrfs_extent_inline_ref *iref;
u64 flags;
u32 item_size;
unsigned long ptr;
unsigned long end;
int extra_size;
int type;
int want;
int ret;
int err = 0;
int skinny_metadata =
btrfs_fs_incompat(root->fs_info,
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
key.objectid = bytenr;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
want = extent_ref_type(parent, owner);
if (insert)
extra_size = btrfs_extent_inline_ref_size(want);
else
extra_size = -1;
if (owner < BTRFS_FIRST_FREE_OBJECTID && skinny_metadata) {
skinny_metadata = 1;
key.type = BTRFS_METADATA_ITEM_KEY;
key.offset = owner;
} else if (skinny_metadata) {
skinny_metadata = 0;
}
again:
ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
if (ret < 0) {
err = ret;
goto out;
}
/*
* We may be a newly converted file system which still has the old fat
* extent entries for metadata, so try and see if we have one of those.
*/
if (ret > 0 && skinny_metadata) {
skinny_metadata = 0;
if (path->slots[0]) {
path->slots[0]--;
btrfs_item_key_to_cpu(path->nodes[0], &key,
path->slots[0]);
if (key.objectid == bytenr &&
key.type == BTRFS_EXTENT_ITEM_KEY &&
key.offset == num_bytes)
ret = 0;
}
if (ret) {
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
btrfs_release_path(path);
goto again;
}
}
if (ret) {
printf("Failed to find [%llu, %u, %llu]\n", key.objectid, key.type, key.offset);
return -ENOENT;
}
BUG_ON(ret);
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
if (item_size < sizeof(*ei)) {
if (!insert) {
err = -ENOENT;
goto out;
}
ret = convert_extent_item_v0(trans, root, path, owner,
extra_size);
if (ret < 0) {
err = ret;
goto out;
}
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
}
#endif
if (item_size < sizeof(*ei)) {
printf("Size is %u, needs to be %u, slot %d\n",
(unsigned)item_size,
(unsigned)sizeof(*ei), path->slots[0]);
btrfs_print_leaf(root, leaf);
return -EINVAL;
}
BUG_ON(item_size < sizeof(*ei));
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
flags = btrfs_extent_flags(leaf, ei);
ptr = (unsigned long)(ei + 1);
end = (unsigned long)ei + item_size;
if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !skinny_metadata) {
ptr += sizeof(struct btrfs_tree_block_info);
BUG_ON(ptr > end);
} else if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
if (!(flags & BTRFS_EXTENT_FLAG_DATA)) {
return -EIO;
}
}
err = -ENOENT;
while (1) {
if (ptr >= end) {
WARN_ON(ptr > end);
break;
}
iref = (struct btrfs_extent_inline_ref *)ptr;
type = btrfs_extent_inline_ref_type(leaf, iref);
if (want < type)
break;
if (want > type) {
ptr += btrfs_extent_inline_ref_size(type);
continue;
}
if (type == BTRFS_EXTENT_DATA_REF_KEY) {
struct btrfs_extent_data_ref *dref;
dref = (struct btrfs_extent_data_ref *)(&iref->offset);
if (match_extent_data_ref(leaf, dref, root_objectid,
owner, offset)) {
err = 0;
break;
}
if (hash_extent_data_ref_item(leaf, dref) <
hash_extent_data_ref(root_objectid, owner, offset))
break;
} else {
u64 ref_offset;
ref_offset = btrfs_extent_inline_ref_offset(leaf, iref);
if (parent > 0) {
if (parent == ref_offset) {
err = 0;
break;
}
if (ref_offset < parent)
break;
} else {
if (root_objectid == ref_offset) {
err = 0;
break;
}
if (ref_offset < root_objectid)
break;
}
}
ptr += btrfs_extent_inline_ref_size(type);
}
if (err == -ENOENT && insert) {
if (item_size + extra_size >=
BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
err = -EAGAIN;
goto out;
}
/*
* To add new inline back ref, we have to make sure
* there is no corresponding back ref item.
* For simplicity, we just do not add new inline back
* ref if there is any back ref item.
*/
if (find_next_key(path, &key) == 0 && key.objectid == bytenr &&
key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
err = -EAGAIN;
goto out;
}
}
*ref_ret = (struct btrfs_extent_inline_ref *)ptr;
out:
return err;
}
static int setup_inline_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_extent_inline_ref *iref,
u64 parent, u64 root_objectid,
u64 owner, u64 offset, int refs_to_add)
{
struct extent_buffer *leaf;
struct btrfs_extent_item *ei;
unsigned long ptr;
unsigned long end;
unsigned long item_offset;
u64 refs;
int size;
int type;
int ret;
leaf = path->nodes[0];
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
item_offset = (unsigned long)iref - (unsigned long)ei;
type = extent_ref_type(parent, owner);
size = btrfs_extent_inline_ref_size(type);
ret = btrfs_extend_item(trans, root, path, size);
BUG_ON(ret);
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
refs = btrfs_extent_refs(leaf, ei);
refs += refs_to_add;
btrfs_set_extent_refs(leaf, ei, refs);
ptr = (unsigned long)ei + item_offset;
end = (unsigned long)ei + btrfs_item_size_nr(leaf, path->slots[0]);
if (ptr < end - size)
memmove_extent_buffer(leaf, ptr + size, ptr,
end - size - ptr);
iref = (struct btrfs_extent_inline_ref *)ptr;
btrfs_set_extent_inline_ref_type(leaf, iref, type);
if (type == BTRFS_EXTENT_DATA_REF_KEY) {
struct btrfs_extent_data_ref *dref;
dref = (struct btrfs_extent_data_ref *)(&iref->offset);
btrfs_set_extent_data_ref_root(leaf, dref, root_objectid);
btrfs_set_extent_data_ref_objectid(leaf, dref, owner);
btrfs_set_extent_data_ref_offset(leaf, dref, offset);
btrfs_set_extent_data_ref_count(leaf, dref, refs_to_add);
} else if (type == BTRFS_SHARED_DATA_REF_KEY) {
struct btrfs_shared_data_ref *sref;
sref = (struct btrfs_shared_data_ref *)(iref + 1);
btrfs_set_shared_data_ref_count(leaf, sref, refs_to_add);
btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
} else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
btrfs_set_extent_inline_ref_offset(leaf, iref, parent);
} else {
btrfs_set_extent_inline_ref_offset(leaf, iref, root_objectid);
}
btrfs_mark_buffer_dirty(leaf);
return 0;
}
static int lookup_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_extent_inline_ref **ref_ret,
u64 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner, u64 offset)
{
int ret;
ret = lookup_inline_extent_backref(trans, root, path, ref_ret,
bytenr, num_bytes, parent,
root_objectid, owner, offset, 0);
if (ret != -ENOENT)
return ret;
btrfs_release_path(path);
*ref_ret = NULL;
if (owner < BTRFS_FIRST_FREE_OBJECTID) {
ret = lookup_tree_block_ref(trans, root, path, bytenr, parent,
root_objectid);
} else {
ret = lookup_extent_data_ref(trans, root, path, bytenr, parent,
root_objectid, owner, offset);
}
return ret;
}
static int update_inline_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_extent_inline_ref *iref,
int refs_to_mod)
{
struct extent_buffer *leaf;
struct btrfs_extent_item *ei;
struct btrfs_extent_data_ref *dref = NULL;
struct btrfs_shared_data_ref *sref = NULL;
unsigned long ptr;
unsigned long end;
u32 item_size;
int size;
int type;
int ret;
u64 refs;
leaf = path->nodes[0];
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
refs = btrfs_extent_refs(leaf, ei);
WARN_ON(refs_to_mod < 0 && refs + refs_to_mod <= 0);
refs += refs_to_mod;
btrfs_set_extent_refs(leaf, ei, refs);
type = btrfs_extent_inline_ref_type(leaf, iref);
if (type == BTRFS_EXTENT_DATA_REF_KEY) {
dref = (struct btrfs_extent_data_ref *)(&iref->offset);
refs = btrfs_extent_data_ref_count(leaf, dref);
} else if (type == BTRFS_SHARED_DATA_REF_KEY) {
sref = (struct btrfs_shared_data_ref *)(iref + 1);
refs = btrfs_shared_data_ref_count(leaf, sref);
} else {
refs = 1;
BUG_ON(refs_to_mod != -1);
}
BUG_ON(refs_to_mod < 0 && refs < -refs_to_mod);
refs += refs_to_mod;
if (refs > 0) {
if (type == BTRFS_EXTENT_DATA_REF_KEY)
btrfs_set_extent_data_ref_count(leaf, dref, refs);
else
btrfs_set_shared_data_ref_count(leaf, sref, refs);
} else {
size = btrfs_extent_inline_ref_size(type);
item_size = btrfs_item_size_nr(leaf, path->slots[0]);
ptr = (unsigned long)iref;
end = (unsigned long)ei + item_size;
if (ptr + size < end)
memmove_extent_buffer(leaf, ptr, ptr + size,
end - ptr - size);
item_size -= size;
ret = btrfs_truncate_item(trans, root, path, item_size, 1);
BUG_ON(ret);
}
btrfs_mark_buffer_dirty(leaf);
return 0;
}
static int insert_inline_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner,
u64 offset, int refs_to_add)
{
struct btrfs_extent_inline_ref *iref;
int ret;
ret = lookup_inline_extent_backref(trans, root, path, &iref,
bytenr, num_bytes, parent,
root_objectid, owner, offset, 1);
if (ret == 0) {
BUG_ON(owner < BTRFS_FIRST_FREE_OBJECTID);
ret = update_inline_extent_backref(trans, root, path, iref,
refs_to_add);
} else if (ret == -ENOENT) {
ret = setup_inline_extent_backref(trans, root, path, iref,
parent, root_objectid,
owner, offset, refs_to_add);
}
return ret;
}
static int insert_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
u64 bytenr, u64 parent, u64 root_objectid,
u64 owner, u64 offset, int refs_to_add)
{
int ret;
if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
ret = insert_extent_data_ref(trans, root, path, bytenr,
parent, root_objectid,
owner, offset, refs_to_add);
} else {
BUG_ON(refs_to_add != 1);
ret = insert_tree_block_ref(trans, root, path, bytenr,
parent, root_objectid);
}
return ret;
}
static int remove_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_extent_inline_ref *iref,
int refs_to_drop, int is_data)
{
int ret;
BUG_ON(!is_data && refs_to_drop != 1);
if (iref) {
ret = update_inline_extent_backref(trans, root, path, iref,
-refs_to_drop);
} else if (is_data) {
ret = remove_extent_data_ref(trans, root, path, refs_to_drop);
} else {
ret = btrfs_del_item(trans, root, path);
}
return ret;
}
int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner, u64 offset)
{
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_extent_item *item;
u64 refs;
int ret;
int err = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 1;
ret = insert_inline_extent_backref(trans, root->fs_info->extent_root,
path, bytenr, num_bytes, parent,
root_objectid, owner, offset, 1);
if (ret == 0)
goto out;
if (ret != -EAGAIN) {
err = ret;
goto out;
}
leaf = path->nodes[0];
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
refs = btrfs_extent_refs(leaf, item);
btrfs_set_extent_refs(leaf, item, refs + 1);
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(path);
path->reada = 1;
/* now insert the actual backref */
ret = insert_extent_backref(trans, root->fs_info->extent_root,
path, bytenr, parent, root_objectid,
owner, offset, 1);
if (ret)
err = ret;
out:
btrfs_free_path(path);
finish_current_insert(trans, root->fs_info->extent_root);
del_pending_extents(trans, root->fs_info->extent_root);
BUG_ON(err);
return err;
}
int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
finish_current_insert(trans, root->fs_info->extent_root);
del_pending_extents(trans, root->fs_info->extent_root);
return 0;
}
int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 bytenr,
u64 offset, int metadata, u64 *refs, u64 *flags)
{
struct btrfs_path *path;
int ret;
struct btrfs_key key;
struct extent_buffer *l;
struct btrfs_extent_item *item;
u32 item_size;
u64 num_refs;
u64 extent_flags;
if (metadata &&
!btrfs_fs_incompat(root->fs_info,
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA)) {
offset = root->leafsize;
metadata = 0;
}
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 1;
key.objectid = bytenr;
key.offset = offset;
if (metadata)
key.type = BTRFS_METADATA_ITEM_KEY;
else
key.type = BTRFS_EXTENT_ITEM_KEY;
again:
ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
0, 0);
if (ret < 0)
goto out;
/*
* Deal with the fact that we may have mixed SKINNY and normal refs. If
* we didn't find what we wanted check and see if we have a normal ref
* right next to us, or re-search if we are on the edge of the leaf just
* to make sure.
*/
if (ret > 0 && metadata) {
if (path->slots[0]) {
path->slots[0]--;
btrfs_item_key_to_cpu(path->nodes[0], &key,
path->slots[0]);
if (key.objectid == bytenr &&
key.type == BTRFS_EXTENT_ITEM_KEY &&
key.offset == root->leafsize)
ret = 0;
}
if (ret) {
btrfs_release_path(path);
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = root->leafsize;
metadata = 0;
goto again;
}
}
if (ret != 0) {
ret = -EIO;
goto out;
}
l = path->nodes[0];
item_size = btrfs_item_size_nr(l, path->slots[0]);
if (item_size >= sizeof(*item)) {
item = btrfs_item_ptr(l, path->slots[0],
struct btrfs_extent_item);
num_refs = btrfs_extent_refs(l, item);
extent_flags = btrfs_extent_flags(l, item);
} else {
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
struct btrfs_extent_item_v0 *ei0;
BUG_ON(item_size != sizeof(*ei0));
ei0 = btrfs_item_ptr(l, path->slots[0],
struct btrfs_extent_item_v0);
num_refs = btrfs_extent_refs_v0(l, ei0);
/* FIXME: this isn't correct for data */
extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
#else
BUG();
#endif
}
item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
if (refs)
*refs = num_refs;
if (flags)
*flags = extent_flags;
out:
btrfs_free_path(path);
return ret;
}
int btrfs_set_block_flags(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, int level, u64 flags)
{
struct btrfs_path *path;
int ret;
struct btrfs_key key;
struct extent_buffer *l;
struct btrfs_extent_item *item;
u32 item_size;
int skinny_metadata =
btrfs_fs_incompat(root->fs_info,
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 1;
key.objectid = bytenr;
if (skinny_metadata) {
key.offset = level;
key.type = BTRFS_METADATA_ITEM_KEY;
} else {
key.offset = root->leafsize;
key.type = BTRFS_EXTENT_ITEM_KEY;
}
again:
ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
0, 0);
if (ret < 0)
goto out;
if (ret > 0 && skinny_metadata) {
skinny_metadata = 0;
if (path->slots[0]) {
path->slots[0]--;
btrfs_item_key_to_cpu(path->nodes[0], &key,
path->slots[0]);
if (key.objectid == bytenr &&
key.offset == root->leafsize &&
key.type == BTRFS_EXTENT_ITEM_KEY)
ret = 0;
}
if (ret) {
btrfs_release_path(path);
key.offset = root->leafsize;
key.type = BTRFS_EXTENT_ITEM_KEY;
goto again;
}
}
if (ret != 0) {
btrfs_print_leaf(root, path->nodes[0]);
printk("failed to find block number %Lu\n",
(unsigned long long)bytenr);
BUG();
}
l = path->nodes[0];
item_size = btrfs_item_size_nr(l, path->slots[0]);
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
if (item_size < sizeof(*item)) {
ret = convert_extent_item_v0(trans, root->fs_info->extent_root,
path, (u64)-1, 0);
if (ret < 0)
goto out;
l = path->nodes[0];
item_size = btrfs_item_size_nr(l, path->slots[0]);
}
#endif
BUG_ON(item_size < sizeof(*item));
item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
flags |= btrfs_extent_flags(l, item);
btrfs_set_extent_flags(l, item, flags);
out:
btrfs_free_path(path);
finish_current_insert(trans, root->fs_info->extent_root);
del_pending_extents(trans, root->fs_info->extent_root);
return ret;
}
static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
int record_parent, int inc)
{
u64 bytenr;
u64 num_bytes;
u64 parent;
u64 ref_root;
u32 nritems;
struct btrfs_key key;
struct btrfs_file_extent_item *fi;
int i;
int level;
int ret = 0;
int (*process_func)(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64, u64, u64, u64, u64, u64);
ref_root = btrfs_header_owner(buf);
nritems = btrfs_header_nritems(buf);
level = btrfs_header_level(buf);
if (!root->ref_cows && level == 0)
return 0;
if (inc)
process_func = btrfs_inc_extent_ref;
else
process_func = btrfs_free_extent;
if (record_parent)
parent = buf->start;
else
parent = 0;
for (i = 0; i < nritems; i++) {
cond_resched();
if (level == 0) {
btrfs_item_key_to_cpu(buf, &key, i);
if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
continue;
fi = btrfs_item_ptr(buf, i,
struct btrfs_file_extent_item);
if (btrfs_file_extent_type(buf, fi) ==
BTRFS_FILE_EXTENT_INLINE)
continue;
bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
if (bytenr == 0)
continue;
num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
key.offset -= btrfs_file_extent_offset(buf, fi);
ret = process_func(trans, root, bytenr, num_bytes,
parent, ref_root, key.objectid,
key.offset);
if (ret) {
WARN_ON(1);
goto fail;
}
} else {
bytenr = btrfs_node_blockptr(buf, i);
num_bytes = btrfs_level_size(root, level - 1);
ret = process_func(trans, root, bytenr, num_bytes,
parent, ref_root, level - 1, 0);
if (ret) {
WARN_ON(1);
goto fail;
}
}
}
return 0;
fail:
WARN_ON(1);
return ret;
}
int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf, int record_parent)
{
return __btrfs_mod_ref(trans, root, buf, record_parent, 1);
}
int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf, int record_parent)
{
return __btrfs_mod_ref(trans, root, buf, record_parent, 0);
}
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;
unsigned long bi;
struct extent_buffer *leaf;
ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
if (ret < 0)
goto fail;
BUG_ON(ret);
leaf = path->nodes[0];
bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
btrfs_mark_buffer_dirty(leaf);
btrfs_release_path(path);
fail:
finish_current_insert(trans, extent_root);
pending_ret = del_pending_extents(trans, extent_root);
if (ret)
return ret;
if (pending_ret)
return pending_ret;
return 0;
}
int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct extent_io_tree *block_group_cache;
struct btrfs_block_group_cache *cache;
int ret;
struct btrfs_path *path;
u64 last = 0;
u64 start;
u64 end;
u64 ptr;
block_group_cache = &root->fs_info->block_group_cache;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
while(1) {
ret = find_first_extent_bit(block_group_cache, last,
&start, &end, BLOCK_GROUP_DIRTY);
if (ret) {
if (last == 0)
break;
last = 0;
continue;
}
last = end + 1;
ret = get_state_private(block_group_cache, start, &ptr);
BUG_ON(ret);
clear_extent_bits(block_group_cache, start, end,
BLOCK_GROUP_DIRTY, GFP_NOFS);
cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
ret = write_one_cache_group(trans, root, path, cache);
}
btrfs_free_path(path);
return 0;
}
static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
u64 flags)
{
struct btrfs_space_info *found;
flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
list_for_each_entry(found, &info->space_info, list) {
if (found->flags & flags)
return found;
}
return NULL;
}
static int free_space_info(struct btrfs_fs_info *fs_info, u64 flags,
u64 total_bytes, u64 bytes_used,
struct btrfs_space_info **space_info)
{
struct btrfs_space_info *found;
/* only support free block group which is empty */
if (bytes_used)
return -ENOTEMPTY;
found = __find_space_info(fs_info, flags);
if (!found)
return -ENOENT;
if (found->total_bytes < total_bytes) {
fprintf(stderr,
"WARNING: bad space info to free %llu only have %llu\n",
total_bytes, found->total_bytes);
return -EINVAL;
}
found->total_bytes -= total_bytes;
if (space_info)
*space_info = found;
return 0;
}
static int update_space_info(struct btrfs_fs_info *info, u64 flags,
u64 total_bytes, u64 bytes_used,
struct btrfs_space_info **space_info)
{
struct btrfs_space_info *found;
found = __find_space_info(info, flags);
if (found) {
found->total_bytes += total_bytes;
found->bytes_used += bytes_used;
if (found->total_bytes < found->bytes_used) {
fprintf(stderr, "warning, bad space info total_bytes "
"%llu used %llu\n",
(unsigned long long)found->total_bytes,
(unsigned long long)found->bytes_used);
}
*space_info = found;
return 0;
}
found = kmalloc(sizeof(*found), GFP_NOFS);
if (!found)
return -ENOMEM;
list_add(&found->list, &info->space_info);
found->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
found->total_bytes = total_bytes;
found->bytes_used = bytes_used;
found->bytes_pinned = 0;
found->full = 0;
*space_info = found;
return 0;
}
static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
{
u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID1 |
BTRFS_BLOCK_GROUP_RAID10 |
BTRFS_BLOCK_GROUP_RAID5 |
BTRFS_BLOCK_GROUP_RAID6 |
BTRFS_BLOCK_GROUP_DUP);
if (extra_flags) {
if (flags & BTRFS_BLOCK_GROUP_DATA)
fs_info->avail_data_alloc_bits |= extra_flags;
if (flags & BTRFS_BLOCK_GROUP_METADATA)
fs_info->avail_metadata_alloc_bits |= extra_flags;
if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
fs_info->avail_system_alloc_bits |= extra_flags;
}
}
static int do_chunk_alloc(struct btrfs_trans_handle *trans,
struct btrfs_root *extent_root, u64 alloc_bytes,
u64 flags)
{
struct btrfs_space_info *space_info;
u64 thresh;
u64 start;
u64 num_bytes;
int ret;
space_info = __find_space_info(extent_root->fs_info, flags);
if (!space_info) {
ret = update_space_info(extent_root->fs_info, flags,
0, 0, &space_info);
BUG_ON(ret);
}
BUG_ON(!space_info);
if (space_info->full)
return 0;
thresh = div_factor(space_info->total_bytes, 7);
if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
thresh)
return 0;
ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes,
space_info->flags);
if (ret == -ENOSPC) {
space_info->full = 1;
return 0;
}
BUG_ON(ret);
ret = btrfs_make_block_group(trans, extent_root, 0, space_info->flags,
BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
BUG_ON(ret);
return 0;
}
static int update_block_group(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, int alloc,
int mark_free)
{
struct btrfs_block_group_cache *cache;
struct btrfs_fs_info *info = root->fs_info;
u64 total = num_bytes;
u64 old_val;
u64 byte_in_group;
u64 start;
u64 end;
/* block accounting for super block */
old_val = btrfs_super_bytes_used(info->super_copy);
if (alloc)
old_val += num_bytes;
else
old_val -= num_bytes;
btrfs_set_super_bytes_used(info->super_copy, old_val);
/* block accounting for root item */
old_val = btrfs_root_used(&root->root_item);
if (alloc)
old_val += num_bytes;
else
old_val -= num_bytes;
btrfs_set_root_used(&root->root_item, old_val);
while(total) {
cache = btrfs_lookup_block_group(info, bytenr);
if (!cache) {
return -1;
}
byte_in_group = bytenr - cache->key.objectid;
WARN_ON(byte_in_group > cache->key.offset);
start = cache->key.objectid;
end = start + cache->key.offset - 1;
set_extent_bits(&info->block_group_cache, start, end,
BLOCK_GROUP_DIRTY, GFP_NOFS);
old_val = btrfs_block_group_used(&cache->item);
num_bytes = min(total, cache->key.offset - byte_in_group);
if (alloc) {
old_val += num_bytes;
cache->space_info->bytes_used += num_bytes;
} else {
old_val -= num_bytes;
cache->space_info->bytes_used -= num_bytes;
if (mark_free) {
set_extent_dirty(&info->free_space_cache,
bytenr, bytenr + num_bytes - 1,
GFP_NOFS);
}
}
btrfs_set_block_group_used(&cache->item, old_val);
total -= num_bytes;
bytenr += num_bytes;
}
return 0;
}
static int update_pinned_extents(struct btrfs_root *root,
u64 bytenr, u64 num, int pin)
{
u64 len;
struct btrfs_block_group_cache *cache;
struct btrfs_fs_info *fs_info = root->fs_info;
if (pin) {
set_extent_dirty(&fs_info->pinned_extents,
bytenr, bytenr + num - 1, GFP_NOFS);
} else {
clear_extent_dirty(&fs_info->pinned_extents,
bytenr, bytenr + num - 1, GFP_NOFS);
}
while (num > 0) {
cache = btrfs_lookup_block_group(fs_info, bytenr);
if (!cache) {
len = min((u64)root->sectorsize, num);
goto next;
}
WARN_ON(!cache);
len = min(num, cache->key.offset -
(bytenr - cache->key.objectid));
if (pin) {
cache->pinned += len;
cache->space_info->bytes_pinned += len;
fs_info->total_pinned += len;
} else {
cache->pinned -= len;
cache->space_info->bytes_pinned -= len;
fs_info->total_pinned -= len;
}
next:
bytenr += len;
num -= len;
}
return 0;
}
int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_io_tree *unpin)
{
u64 start;
u64 end;
int ret;
struct extent_io_tree *free_space_cache;
free_space_cache = &root->fs_info->free_space_cache;
while(1) {
ret = find_first_extent_bit(unpin, 0, &start, &end,
EXTENT_DIRTY);
if (ret)
break;
update_pinned_extents(root, start, end + 1 - start, 0);
clear_extent_dirty(unpin, start, end, GFP_NOFS);
set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
}
return 0;
}
static int extent_root_pending_ops(struct btrfs_fs_info *info)
{
u64 start;
u64 end;
int ret;
ret = find_first_extent_bit(&info->extent_ins, 0, &start,
&end, EXTENT_LOCKED);
if (!ret) {
ret = find_first_extent_bit(&info->pending_del, 0, &start, &end,
EXTENT_LOCKED);
}
return ret == 0;
}
static int finish_current_insert(struct btrfs_trans_handle *trans,
struct btrfs_root *extent_root)
{
u64 start;
u64 end;
u64 priv;
struct btrfs_fs_info *info = extent_root->fs_info;
struct pending_extent_op *extent_op;
struct btrfs_key key;
int ret;
int skinny_metadata =
btrfs_fs_incompat(extent_root->fs_info,
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
while(1) {
ret = find_first_extent_bit(&info->extent_ins, 0, &start,
&end, EXTENT_LOCKED);
if (ret)
break;
ret = get_state_private(&info->extent_ins, start, &priv);
BUG_ON(ret);
extent_op = (struct pending_extent_op *)(unsigned long)priv;
if (extent_op->type == PENDING_EXTENT_INSERT) {
key.objectid = start;
if (skinny_metadata) {
key.offset = extent_op->level;
key.type = BTRFS_METADATA_ITEM_KEY;
} else {
key.offset = extent_op->num_bytes;
key.type = BTRFS_EXTENT_ITEM_KEY;
}
ret = alloc_reserved_tree_block(trans, extent_root,
extent_root->root_key.objectid,
trans->transid,
extent_op->flags,
&extent_op->key,
extent_op->level, &key);
BUG_ON(ret);
} else {
BUG_ON(1);
}
clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
GFP_NOFS);
kfree(extent_op);
}
return 0;
}
static int pin_down_bytes(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, int is_data)
{
int err = 0;
struct extent_buffer *buf;
if (is_data)
goto pinit;
buf = btrfs_find_tree_block(root, bytenr, num_bytes);
if (!buf)
goto pinit;
/* we can reuse a block if it hasn't been written
* and it is from this transaction. We can't
* reuse anything from the tree log root because
* it has tiny sub-transactions.
*/
if (btrfs_buffer_uptodate(buf, 0)) {
u64 header_owner = btrfs_header_owner(buf);
u64 header_transid = btrfs_header_generation(buf);
if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
header_transid == trans->transid &&
!btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
clean_tree_block(NULL, root, buf);
free_extent_buffer(buf);
return 1;
}
}
free_extent_buffer(buf);
pinit:
update_pinned_extents(root, bytenr, num_bytes, 1);
BUG_ON(err < 0);
return 0;
}
void btrfs_pin_extent(struct btrfs_fs_info *fs_info,
u64 bytenr, u64 num_bytes)
{
update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 1);
}
void btrfs_unpin_extent(struct btrfs_fs_info *fs_info,
u64 bytenr, u64 num_bytes)
{
update_pinned_extents(fs_info->extent_root, bytenr, num_bytes, 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 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner_objectid,
u64 owner_offset, int refs_to_drop)
{
struct btrfs_key key;
struct btrfs_path *path;
struct btrfs_extent_ops *ops = root->fs_info->extent_ops;
struct btrfs_root *extent_root = root->fs_info->extent_root;
struct extent_buffer *leaf;
struct btrfs_extent_item *ei;
struct btrfs_extent_inline_ref *iref;
int ret;
int is_data;
int extent_slot = 0;
int found_extent = 0;
int num_to_del = 1;
u32 item_size;
u64 refs;
int skinny_metadata =
btrfs_fs_incompat(extent_root->fs_info,
BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA);
if (root->fs_info->free_extent_hook) {
root->fs_info->free_extent_hook(trans, root, bytenr, num_bytes,
parent, root_objectid, owner_objectid,
owner_offset, refs_to_drop);
}
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 1;
is_data = owner_objectid >= BTRFS_FIRST_FREE_OBJECTID;
if (is_data)
skinny_metadata = 0;
BUG_ON(!is_data && refs_to_drop != 1);
ret = lookup_extent_backref(trans, extent_root, path, &iref,
bytenr, num_bytes, parent,
root_objectid, owner_objectid,
owner_offset);
if (ret == 0) {
extent_slot = path->slots[0];
while (extent_slot >= 0) {
btrfs_item_key_to_cpu(path->nodes[0], &key,
extent_slot);
if (key.objectid != bytenr)
break;
if (key.type == BTRFS_EXTENT_ITEM_KEY &&
key.offset == num_bytes) {
found_extent = 1;
break;
}
if (key.type == BTRFS_METADATA_ITEM_KEY &&
key.offset == owner_objectid) {
found_extent = 1;
break;
}
if (path->slots[0] - extent_slot > 5)
break;
extent_slot--;
}
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
item_size = btrfs_item_size_nr(path->nodes[0], extent_slot);
if (found_extent && item_size < sizeof(*ei))
found_extent = 0;
#endif
if (!found_extent) {
BUG_ON(iref);
ret = remove_extent_backref(trans, extent_root, path,
NULL, refs_to_drop,
is_data);
BUG_ON(ret);
btrfs_release_path(path);
key.objectid = bytenr;
if (skinny_metadata) {
key.type = BTRFS_METADATA_ITEM_KEY;
key.offset = owner_objectid;
} else {
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
}
ret = btrfs_search_slot(trans, extent_root,
&key, path, -1, 1);
if (ret > 0 && skinny_metadata && path->slots[0]) {
path->slots[0]--;
btrfs_item_key_to_cpu(path->nodes[0],
&key,
path->slots[0]);
if (key.objectid == bytenr &&
key.type == BTRFS_EXTENT_ITEM_KEY &&
key.offset == num_bytes)
ret = 0;
}
if (ret > 0 && skinny_metadata) {
skinny_metadata = 0;
btrfs_release_path(path);
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
ret = btrfs_search_slot(trans, extent_root,
&key, path, -1, 1);
}
if (ret) {
printk(KERN_ERR "umm, got %d back from search"
", was looking for %llu\n", ret,
(unsigned long long)bytenr);
btrfs_print_leaf(extent_root, path->nodes[0]);
}
BUG_ON(ret);
extent_slot = path->slots[0];
}
} else {
printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
"parent %llu root %llu owner %llu offset %llu\n",
(unsigned long long)bytenr,
(unsigned long long)parent,
(unsigned long long)root_objectid,
(unsigned long long)owner_objectid,
(unsigned long long)owner_offset);
ret = -EIO;
goto fail;
}
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, extent_slot);
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
if (item_size < sizeof(*ei)) {
BUG_ON(found_extent || extent_slot != path->slots[0]);
ret = convert_extent_item_v0(trans, extent_root, path,
owner_objectid, 0);
BUG_ON(ret < 0);
btrfs_release_path(path);
key.objectid = bytenr;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = num_bytes;
ret = btrfs_search_slot(trans, extent_root, &key, path,
-1, 1);
if (ret) {
printk(KERN_ERR "umm, got %d back from search"
", was looking for %llu\n", ret,
(unsigned long long)bytenr);
btrfs_print_leaf(extent_root, path->nodes[0]);
}
BUG_ON(ret);
extent_slot = path->slots[0];
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, extent_slot);
}
#endif
BUG_ON(item_size < sizeof(*ei));
ei = btrfs_item_ptr(leaf, extent_slot,
struct btrfs_extent_item);
if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID &&
key.type == BTRFS_EXTENT_ITEM_KEY) {
struct btrfs_tree_block_info *bi;
BUG_ON(item_size < sizeof(*ei) + sizeof(*bi));
bi = (struct btrfs_tree_block_info *)(ei + 1);
WARN_ON(owner_objectid != btrfs_tree_block_level(leaf, bi));
}
refs = btrfs_extent_refs(leaf, ei);
BUG_ON(refs < refs_to_drop);
refs -= refs_to_drop;
if (refs > 0) {
/*
* In the case of inline back ref, reference count will
* be updated by remove_extent_backref
*/
if (iref) {
BUG_ON(!found_extent);
} else {
btrfs_set_extent_refs(leaf, ei, refs);
btrfs_mark_buffer_dirty(leaf);
}
if (found_extent) {
ret = remove_extent_backref(trans, extent_root, path,
iref, refs_to_drop,
is_data);
BUG_ON(ret);
}
} else {
int mark_free = 0;
int pin = 1;
if (found_extent) {
BUG_ON(is_data && refs_to_drop !=
extent_data_ref_count(root, path, iref));
if (iref) {
BUG_ON(path->slots[0] != extent_slot);
} else {
BUG_ON(path->slots[0] != extent_slot + 1);
path->slots[0] = extent_slot;
num_to_del = 2;
}
}
if (ops && ops->free_extent) {
ret = ops->free_extent(root, bytenr, num_bytes);
if (ret > 0) {
pin = 0;
mark_free = 0;
}
}
if (pin) {
ret = pin_down_bytes(trans, root, bytenr, num_bytes,
is_data);
if (ret > 0)
mark_free = 1;
BUG_ON(ret < 0);
}
ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
num_to_del);
BUG_ON(ret);
btrfs_release_path(path);
if (is_data) {
ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
BUG_ON(ret);
}
update_block_group(trans, root, bytenr, num_bytes, 0, mark_free);
}
fail:
btrfs_free_path(path);
finish_current_insert(trans, extent_root);
return ret;
}
/*
* find all the blocks marked as pending in the radix tree and remove
* them from the extent map
*/
static int del_pending_extents(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root)
{
int ret;
int err = 0;
u64 start;
u64 end;
u64 priv;
struct extent_io_tree *pending_del;
struct extent_io_tree *extent_ins;
struct pending_extent_op *extent_op;
extent_ins = &extent_root->fs_info->extent_ins;
pending_del = &extent_root->fs_info->pending_del;
while(1) {
ret = find_first_extent_bit(pending_del, 0, &start, &end,
EXTENT_LOCKED);
if (ret)
break;
ret = get_state_private(pending_del, start, &priv);
BUG_ON(ret);
extent_op = (struct pending_extent_op *)(unsigned long)priv;
clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
GFP_NOFS);
if (!test_range_bit(extent_ins, start, end,
EXTENT_LOCKED, 0)) {
ret = __free_extent(trans, extent_root,
start, end + 1 - start, 0,
extent_root->root_key.objectid,
extent_op->level, 0, 1);
kfree(extent_op);
} else {
kfree(extent_op);
ret = get_state_private(extent_ins, start, &priv);
BUG_ON(ret);
extent_op = (struct pending_extent_op *)
(unsigned long)priv;
clear_extent_bits(extent_ins, start, end,
EXTENT_LOCKED, GFP_NOFS);
if (extent_op->type == PENDING_BACKREF_UPDATE)
BUG_ON(1);
kfree(extent_op);
}
if (ret)
err = ret;
}
return err;
}
/*
* remove an extent from the root, returns 0 on success
*/
int btrfs_free_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner, u64 offset)
{
struct btrfs_root *extent_root = root->fs_info->extent_root;
int pending_ret;
int ret;
WARN_ON(num_bytes < root->sectorsize);
if (root == extent_root) {
struct pending_extent_op *extent_op;
extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
BUG_ON(!extent_op);
extent_op->type = PENDING_EXTENT_DELETE;
extent_op->bytenr = bytenr;
extent_op->num_bytes = num_bytes;
extent_op->level = (int)owner;
set_extent_bits(&root->fs_info->pending_del,
bytenr, bytenr + num_bytes - 1,
EXTENT_LOCKED, GFP_NOFS);
set_state_private(&root->fs_info->pending_del,
bytenr, (unsigned long)extent_op);
return 0;
}
ret = __free_extent(trans, root, bytenr, num_bytes, parent,
root_objectid, owner, offset, 1);
pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
return ret ? ret : pending_ret;
}
static u64 stripe_align(struct btrfs_root *root, u64 val)
{
u64 mask = ((u64)root->stripesize - 1);
u64 ret = (val + mask) & ~mask;
return ret;
}
/*
* walks the btree of allocated extents and find a hole of a given size.
* The key ins is changed to record the hole:
* ins->objectid == block start
* ins->flags = BTRFS_EXTENT_ITEM_KEY
* ins->offset == number of blocks
* Any available blocks before search_start are skipped.
*/
static int noinline find_free_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *orig_root,
u64 num_bytes, u64 empty_size,
u64 search_start, u64 search_end,
u64 hint_byte, struct btrfs_key *ins,
u64 exclude_start, u64 exclude_nr,
int data)
{
int ret;
u64 orig_search_start = search_start;
struct btrfs_root * root = orig_root->fs_info->extent_root;
struct btrfs_fs_info *info = root->fs_info;
u64 total_needed = num_bytes;
struct btrfs_block_group_cache *block_group;
int full_scan = 0;
int wrapped = 0;
WARN_ON(num_bytes < root->sectorsize);
btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
search_start = stripe_align(root, search_start);
if (hint_byte) {
block_group = btrfs_lookup_first_block_group(info, hint_byte);
if (!block_group)
hint_byte = search_start;
block_group = btrfs_find_block_group(root, block_group,
hint_byte, data, 1);
} else {
block_group = btrfs_find_block_group(root,
trans->block_group,
search_start, data, 1);
}
total_needed += empty_size;
check_failed:
search_start = stripe_align(root, search_start);
if (!block_group) {
block_group = btrfs_lookup_first_block_group(info,
search_start);
if (!block_group)
block_group = btrfs_lookup_first_block_group(info,
orig_search_start);
}
ret = find_search_start(root, &block_group, &search_start,
total_needed, data);
if (ret)
goto new_group;
ins->objectid = search_start;
ins->offset = num_bytes;
if (ins->objectid + num_bytes >
block_group->key.objectid + block_group->key.offset) {
search_start = block_group->key.objectid +
block_group->key.offset;
goto new_group;
}
if (test_range_bit(&info->extent_ins, ins->objectid,
ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
search_start = ins->objectid + num_bytes;
goto new_group;
}
if (test_range_bit(&info->pinned_extents, ins->objectid,
ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
search_start = ins->objectid + num_bytes;
goto new_group;
}
if (info->excluded_extents &&
test_range_bit(info->excluded_extents, ins->objectid,
ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
search_start = ins->objectid + num_bytes;
goto new_group;
}
if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
ins->objectid < exclude_start + exclude_nr)) {
search_start = exclude_start + exclude_nr;
goto new_group;
}
if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
if (check_crossing_stripes(ins->objectid, num_bytes)) {
search_start = round_down(ins->objectid + num_bytes,
BTRFS_STRIPE_LEN);
goto new_group;
}
block_group = btrfs_lookup_block_group(info, ins->objectid);
if (block_group)
trans->block_group = block_group;
}
ins->offset = num_bytes;
return 0;
new_group:
block_group = btrfs_lookup_first_block_group(info, search_start);
if (!block_group) {
search_start = orig_search_start;
if (full_scan) {
ret = -ENOSPC;
goto error;
}
if (wrapped) {
if (!full_scan)
total_needed -= empty_size;
full_scan = 1;
} else
wrapped = 1;
}
cond_resched();
block_group = btrfs_find_block_group(root, block_group,
search_start, data, 0);
goto check_failed;
error:
return ret;
}
int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 num_bytes, u64 empty_size,
u64 hint_byte, u64 search_end,
struct btrfs_key *ins, int data)
{
int ret;
u64 search_start = 0;
u64 alloc_profile;
struct btrfs_fs_info *info = root->fs_info;
if (info->extent_ops) {
struct btrfs_extent_ops *ops = info->extent_ops;
ret = ops->alloc_extent(root, num_bytes, hint_byte, ins, !data);
BUG_ON(ret);
goto found;
}
if (data) {
alloc_profile = info->avail_data_alloc_bits &
info->data_alloc_profile;
data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
} else if ((info->system_allocs > 0 || root == info->chunk_root) &&
info->system_allocs >= 0) {
alloc_profile = info->avail_system_alloc_bits &
info->system_alloc_profile;
data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
} else {
alloc_profile = info->avail_metadata_alloc_bits &
info->metadata_alloc_profile;
data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
}
if (root->ref_cows) {
if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
ret = do_chunk_alloc(trans, root->fs_info->extent_root,
num_bytes,
BTRFS_BLOCK_GROUP_METADATA);
BUG_ON(ret);
}
ret = do_chunk_alloc(trans, root->fs_info->extent_root,
num_bytes + 2 * 1024 * 1024, data);
BUG_ON(ret);
}
WARN_ON(num_bytes < root->sectorsize);
ret = find_free_extent(trans, root, num_bytes, empty_size,
search_start, search_end, hint_byte, ins,
trans->alloc_exclude_start,
trans->alloc_exclude_nr, data);
BUG_ON(ret);
found:
clear_extent_dirty(&root->fs_info->free_space_cache,
ins->objectid, ins->objectid + ins->offset - 1,
GFP_NOFS);
return ret;
}