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btrfs-progs/extent-tree.c
Qu Wenruo 516f1e963a btrfs-progs: block-group: rename write_one_cache_group() 
The name of this function contains the word "cache", which is left from
the era where btrfs_block_group is called btrfs_block_group_cache.

Now this "cache" doesn't match anything, and we have better namings for
functions like read/insert/remove_block_group_item().

Rename it to update_block_group_item().

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-05-11 21:31:48 +02:00

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/*
* 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 <math.h>
#include "kerncompat.h"
#include "kernel-lib/radix-tree.h"
#include "kernel-lib/rbtree.h"
#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
#include "transaction.h"
#include "crypto/crc32c.h"
#include "volumes.h"
#include "free-space-cache.h"
#include "kernel-shared/free-space-tree.h"
#include "common/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 __free_extent(struct btrfs_trans_handle *trans,
u64 bytenr, u64 num_bytes, u64 parent,
u64 root_objectid, u64 owner_objectid,
u64 owner_offset, int refs_to_drop);
static struct btrfs_block_group *
btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group
*hint, u64 search_start, int data, int owner);
static int remove_sb_from_cache(struct btrfs_root *root,
struct btrfs_block_group *cache)
{
u64 bytenr;
u64 *logical;
int stripe_len;
int i, nr, ret;
struct btrfs_fs_info *fs_info = root->fs_info;
struct extent_io_tree *free_space_cache;
free_space_cache = &fs_info->free_space_cache;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
ret = btrfs_rmap_block(fs_info, cache->start, bytenr,
&logical, &nr, &stripe_len);
BUG_ON(ret);
while (nr--) {
clear_extent_dirty(free_space_cache, logical[nr],
logical[nr] + stripe_len - 1);
}
kfree(logical);
}
return 0;
}
static int cache_block_group(struct btrfs_root *root,
struct btrfs_block_group *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 = READA_FORWARD;
last = max_t(u64, block_group->start, 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->start) {
goto next;
}
if (key.objectid >= block_group->start + block_group->length) {
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);
}
if (key.type == BTRFS_METADATA_ITEM_KEY)
last = key.objectid + root->fs_info->nodesize;
else
last = key.objectid + key.offset;
}
next:
path->slots[0]++;
}
if (block_group->start + block_group->length > last) {
hole_size = block_group->start + block_group->length - last;
set_extent_dirty(free_space_cache, last, last + hole_size - 1);
}
remove_sb_from_cache(root, block_group);
block_group->cached = 1;
err:
btrfs_free_path(path);
return 0;
}
/*
* This adds the block group to the fs_info rb tree for the block group cache
*/
static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
struct btrfs_block_group *block_group)
{
struct rb_node **p;
struct rb_node *parent = NULL;
struct btrfs_block_group *cache;
ASSERT(block_group->length != 0);
p = &info->block_group_cache_tree.rb_node;
while (*p) {
parent = *p;
cache = rb_entry(parent, struct btrfs_block_group,
cache_node);
if (block_group->start < cache->start)
p = &(*p)->rb_left;
else if (block_group->start > cache->start)
p = &(*p)->rb_right;
else
return -EEXIST;
}
rb_link_node(&block_group->cache_node, parent, p);
rb_insert_color(&block_group->cache_node,
&info->block_group_cache_tree);
return 0;
}
/*
* This will return the block group which contains @bytenr if it exists.
* If found nothing, the return depends on @next.
*
* @next:
* if 0, return NULL if there's no block group containing the bytenr.
* if 1, return the block group which starts after @bytenr.
*/
static struct btrfs_block_group *block_group_cache_tree_search(
struct btrfs_fs_info *info, u64 bytenr, int next)
{
struct btrfs_block_group *cache, *ret = NULL;
struct rb_node *n;
u64 end, start;
n = info->block_group_cache_tree.rb_node;
while (n) {
cache = rb_entry(n, struct btrfs_block_group,
cache_node);
end = cache->start + cache->length - 1;
start = cache->start;
if (bytenr < start) {
if (next && (!ret || start < ret->start))
ret = cache;
n = n->rb_left;
} else if (bytenr > start) {
if (bytenr <= end) {
ret = cache;
break;
}
n = n->rb_right;
} else {
ret = cache;
break;
}
}
return ret;
}
/*
* Return the block group that contains @bytenr, otherwise return the next one
* that starts after @bytenr
*/
struct btrfs_block_group *btrfs_lookup_first_block_group(
struct btrfs_fs_info *info, u64 bytenr)
{
return block_group_cache_tree_search(info, bytenr, 1);
}
/*
* Return the block group that contains the given bytenr
*/
struct btrfs_block_group *btrfs_lookup_block_group(
struct btrfs_fs_info *info, u64 bytenr)
{
return block_group_cache_tree_search(info, bytenr, 0);
}
static int block_group_bits(struct btrfs_block_group *cache, u64 bits)
{
return (cache->flags & bits) == bits;
}
static int noinline find_search_start(struct btrfs_root *root,
struct btrfs_block_group **cache_ret,
u64 *start_ret, int num, int data)
{
int ret;
struct btrfs_block_group *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->start);
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->start + cache->length) {
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);
return -ENOENT;
}
return -ENOSPC;
new_group:
last = cache->start + cache->length;
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 struct btrfs_block_group *
btrfs_find_block_group(struct btrfs_root *root, struct btrfs_block_group
*hint, u64 search_start, int data, int owner)
{
struct btrfs_block_group *cache;
struct btrfs_block_group *found_group = NULL;
struct btrfs_fs_info *info = root->fs_info;
u64 used;
u64 last = 0;
u64 hint_last;
u64 free_check;
int full_search = 0;
int factor = 10;
if (!owner)
factor = 10;
if (search_start) {
struct btrfs_block_group *shint;
shint = btrfs_lookup_block_group(info, search_start);
if (shint && !shint->ro && block_group_bits(shint, data)) {
used = shint->used;
if (used + shint->pinned <
div_factor(shint->length, factor)) {
return shint;
}
}
}
if (hint && !hint->ro && block_group_bits(hint, data)) {
used = hint->used;
if (used + hint->pinned <
div_factor(hint->length, factor)) {
return hint;
}
last = hint->start + hint->length;
hint_last = last;
} else {
if (hint)
hint_last = max(hint->start , search_start);
else
hint_last = search_start;
last = hint_last;
}
again:
while(1) {
cache = btrfs_lookup_first_block_group(info, last);
if (!cache)
break;
last = cache->start + cache->length;
used = cache->used;
if (!cache->ro && block_group_bits(cache, data)) {
if (full_search)
free_check = cache->length;
else
free_check = div_factor(cache->length, 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.
*/
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;
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);
} 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);
btrfs_mark_buffer_dirty(leaf);
}
return ret;
}
static noinline u32 extent_data_ref_count(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);
} 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;
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, 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) {
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]);
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(leaf);
return -EINVAL;
}
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_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(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(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(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;
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);
/* 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);
BUG_ON(err);
return err;
}
int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, 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(fs_info, SKINNY_METADATA)) {
offset = fs_info->nodesize;
metadata = 0;
}
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
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, 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 == fs_info->nodesize)
ret = 0;
}
if (ret) {
btrfs_release_path(path);
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = fs_info->nodesize;
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 {
BUG();
}
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, u64 bytenr,
int level, u64 flags)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
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(fs_info, SKINNY_METADATA);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = bytenr;
if (skinny_metadata) {
key.offset = level;
key.type = BTRFS_METADATA_ITEM_KEY;
} else {
key.offset = fs_info->nodesize;
key.type = BTRFS_EXTENT_ITEM_KEY;
}
again:
ret = btrfs_search_slot(trans, 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 == fs_info->nodesize &&
key.type == BTRFS_EXTENT_ITEM_KEY)
ret = 0;
}
if (ret) {
btrfs_release_path(path);
key.offset = fs_info->nodesize;
key.type = BTRFS_EXTENT_ITEM_KEY;
goto again;
}
}
if (ret != 0) {
btrfs_print_leaf(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]);
if (item_size < sizeof(*item)) {
error(
"unsupported or corrupted extent item, item size=%u expect minimal size=%zu",
item_size, sizeof(*item));
ret = -EUCLEAN;
goto out;
}
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);
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 (key.type != 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 = root->fs_info->nodesize;
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 update_block_group_item(struct btrfs_trans_handle *trans,
struct btrfs_path *path,
struct btrfs_block_group *cache)
{
int ret;
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root = fs_info->extent_root;
unsigned long bi;
struct btrfs_block_group_item bgi;
struct extent_buffer *leaf;
struct btrfs_key key;
key.objectid = cache->start;
key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
key.offset = cache->length;
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
if (ret > 0)
ret = -ENOENT;
if (ret < 0)
goto fail;
leaf = path->nodes[0];
bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
btrfs_set_stack_block_group_used(&bgi, cache->used);
btrfs_set_stack_block_group_flags(&bgi, cache->flags);
btrfs_set_stack_block_group_chunk_objectid(&bgi,
BTRFS_FIRST_CHUNK_TREE_OBJECTID);
write_extent_buffer(leaf, &bgi, bi, sizeof(bgi));
btrfs_mark_buffer_dirty(leaf);
fail:
btrfs_release_path(path);
return ret;
}
int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans)
{
struct btrfs_block_group *cache;
struct btrfs_path *path;
int ret = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
while (!list_empty(&trans->dirty_bgs)) {
cache = list_first_entry(&trans->dirty_bgs,
struct btrfs_block_group, dirty_list);
list_del_init(&cache->dirty_list);
ret = update_block_group_item(trans, path, cache);
if (ret)
break;
}
btrfs_free_path(path);
return ret;
}
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;
}
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->bytes_reserved = 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_RAID1C3 |
BTRFS_BLOCK_GROUP_RAID1C4 |
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_fs_info *fs_info, 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(fs_info, flags);
if (!space_info) {
ret = update_space_info(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 +
space_info->bytes_reserved + alloc_bytes) < thresh)
return 0;
/*
* Avoid allocating given chunk type
*/
if (fs_info->avoid_meta_chunk_alloc &&
(flags & BTRFS_BLOCK_GROUP_METADATA))
return 0;
if (fs_info->avoid_sys_chunk_alloc &&
(flags & BTRFS_BLOCK_GROUP_SYSTEM))
return 0;
/*
* We're going to allocate new chunk, during the process, we will
* allocate new tree blocks, which can trigger new chunk allocation
* again. Avoid the recursion.
*/
if (trans->allocating_chunk)
return 0;
trans->allocating_chunk = 1;
ret = btrfs_alloc_chunk(trans, fs_info, &start, &num_bytes,
space_info->flags);
if (ret == -ENOSPC) {
space_info->full = 1;
trans->allocating_chunk = 0;
return 0;
}
BUG_ON(ret);
ret = btrfs_make_block_group(trans, fs_info, 0, space_info->flags,
start, num_bytes);
BUG_ON(ret);
trans->allocating_chunk = 0;
return 0;
}
static int update_block_group(struct btrfs_trans_handle *trans, u64 bytenr,
u64 num_bytes, int alloc, int mark_free)
{
struct btrfs_fs_info *info = trans->fs_info;
struct btrfs_block_group *cache;
u64 total = num_bytes;
u64 old_val;
u64 byte_in_group;
/* 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);
while(total) {
cache = btrfs_lookup_block_group(info, bytenr);
if (!cache) {
return -1;
}
byte_in_group = bytenr - cache->start;
WARN_ON(byte_in_group > cache->length);
if (list_empty(&cache->dirty_list))
list_add_tail(&cache->dirty_list, &trans->dirty_bgs);
old_val = cache->used;
num_bytes = min(total, cache->length- 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);
}
}
cache->used = old_val;
total -= num_bytes;
bytenr += num_bytes;
}
return 0;
}
static int update_pinned_extents(struct btrfs_fs_info *fs_info,
u64 bytenr, u64 num, int pin)
{
u64 len;
struct btrfs_block_group *cache;
if (pin) {
set_extent_dirty(&fs_info->pinned_extents,
bytenr, bytenr + num - 1);
} else {
clear_extent_dirty(&fs_info->pinned_extents,
bytenr, bytenr + num - 1);
}
while (num > 0) {
cache = btrfs_lookup_block_group(fs_info, bytenr);
if (!cache) {
len = min((u64)fs_info->sectorsize, num);
goto next;
}
WARN_ON(!cache);
len = min(num, cache->length - (bytenr - cache->start));
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;
}
void btrfs_finish_extent_commit(struct btrfs_trans_handle *trans)
{
u64 start;
u64 end;
int ret;
struct btrfs_fs_info *fs_info = trans->fs_info;
struct extent_io_tree *free_space_cache = &fs_info->free_space_cache;
struct extent_io_tree *pinned_extents = &fs_info->pinned_extents;
while(1) {
ret = find_first_extent_bit(pinned_extents, 0, &start, &end,
EXTENT_DIRTY);
if (ret)
break;
update_pinned_extents(trans->fs_info, start, end + 1 - start,
0);
clear_extent_dirty(pinned_extents, start, end);
set_extent_dirty(free_space_cache, start, end);
}
}
static int pin_down_bytes(struct btrfs_trans_handle *trans, 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(trans->fs_info, 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(buf);
free_extent_buffer(buf);
return 1;
}
}
free_extent_buffer(buf);
pinit:
update_pinned_extents(trans->fs_info, 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, bytenr, num_bytes, 1);
}
void btrfs_unpin_extent(struct btrfs_fs_info *fs_info,
u64 bytenr, u64 num_bytes)
{
update_pinned_extents(fs_info, bytenr, num_bytes, 0);
}
/*
* remove an extent from the root, returns 0 on success
*/
static int __free_extent(struct btrfs_trans_handle *trans,
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_root *extent_root = trans->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, SKINNY_METADATA);
if (trans->fs_info->free_extent_hook) {
trans->fs_info->free_extent_hook(trans->fs_info, bytenr, num_bytes,
parent, root_objectid, owner_objectid,
owner_offset, refs_to_drop);
}
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
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--;
}
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(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);
printf("path->slots[0]: %d path->nodes[0]:\n", path->slots[0]);
btrfs_print_leaf(path->nodes[0]);
ret = -EIO;
goto fail;
}
leaf = path->nodes[0];
item_size = btrfs_item_size_nr(leaf, extent_slot);
if (item_size < sizeof(*ei)) {
error(
"unsupported or corrupted extent item, item size=%u expect minimal size=%zu",
item_size, sizeof(*ei));
ret = -EUCLEAN;
goto fail;
}
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;
if (found_extent) {
BUG_ON(is_data && refs_to_drop !=
extent_data_ref_count(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;
}
}
ret = pin_down_bytes(trans, 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, bytenr, num_bytes);
BUG_ON(ret);
}
ret = add_to_free_space_tree(trans, bytenr, num_bytes);
if (ret) {
goto fail;
}
update_block_group(trans, bytenr, num_bytes, 0, mark_free);
}
fail:
btrfs_free_path(path);
return ret;
}
int btrfs_free_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
u64 parent, int last_ref)
{
return btrfs_free_extent(trans, root, buf->start, buf->len, parent,
root->root_key.objectid,
btrfs_header_level(buf), 0);
}
/*
* 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)
{
int ret;
WARN_ON(num_bytes < root->fs_info->sectorsize);
/*
* tree log blocks never actually go into the extent allocation
* tree, just update pinning info and exit early.
*/
if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
printf("PINNING EXTENTS IN LOG TREE\n");
WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
btrfs_pin_extent(trans->fs_info, bytenr, num_bytes);
ret = 0;
} else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
BUG_ON(offset);
ret = btrfs_add_delayed_tree_ref(trans->fs_info, trans,
bytenr, num_bytes, parent,
root_objectid, (int)owner,
BTRFS_DROP_DELAYED_REF,
NULL, NULL, NULL);
} else {
ret = __free_extent(trans, bytenr, num_bytes, parent,
root_objectid, owner, offset, 1);
}
return ret;
}
static u64 stripe_align(struct btrfs_root *root, u64 val)
{
return round_up(val, (u64)root->fs_info->stripesize);
}
/*
* 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 *block_group;
int full_scan = 0;
int wrapped = 0;
WARN_ON(num_bytes < info->sectorsize);
ins->type = 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->start + block_group->length) {
search_start = block_group->start + block_group->length;
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(info, ins->objectid, num_bytes)) {
struct btrfs_block_group *bg_cache;
u64 bg_offset;
bg_cache = btrfs_lookup_block_group(info, ins->objectid);
if (!bg_cache)
goto no_bg_cache;
bg_offset = ins->objectid - bg_cache->start;
search_start = round_up(
bg_offset + num_bytes, BTRFS_STRIPE_LEN) +
bg_cache->start;
goto new_group;
}
no_bg_cache:
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, bool is_data)
{
int ret;
u64 search_start = 0;
u64 alloc_profile;
u64 profile;
struct btrfs_fs_info *info = root->fs_info;
if (is_data) {
alloc_profile = info->avail_data_alloc_bits &
info->data_alloc_profile;
profile = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
} else if (info->system_allocs == 1 || root == info->chunk_root) {
alloc_profile = info->avail_system_alloc_bits &
info->system_alloc_profile;
profile = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
} else {
alloc_profile = info->avail_metadata_alloc_bits &
info->metadata_alloc_profile;
profile = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
}
/*
* Also preallocate metadata for csum tree and fs trees (root->ref_cows
* already set), as they can consume a lot of metadata space.
* Pre-allocate to avoid unexpected ENOSPC.
*/
if (root->ref_cows ||
root->root_key.objectid == BTRFS_CSUM_TREE_OBJECTID) {
if (!(profile & BTRFS_BLOCK_GROUP_METADATA)) {
ret = do_chunk_alloc(trans, info,
num_bytes,
BTRFS_BLOCK_GROUP_METADATA);
BUG_ON(ret);
}
ret = do_chunk_alloc(trans, info,
num_bytes + SZ_2M, profile);
BUG_ON(ret);
}
WARN_ON(num_bytes < info->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, profile);
if (ret < 0)
return ret;
clear_extent_dirty(&info->free_space_cache,
ins->objectid, ins->objectid + ins->offset - 1);
return ret;
}
static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_delayed_ref_node *node,
struct btrfs_delayed_extent_op *extent_op)
{
struct btrfs_delayed_tree_ref *ref = btrfs_delayed_node_to_tree_ref(node);
bool skinny_metadata = btrfs_fs_incompat(trans->fs_info, SKINNY_METADATA);
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_extent_item *extent_item;
struct btrfs_extent_inline_ref *iref;
struct btrfs_space_info *sinfo;
struct extent_buffer *leaf;
struct btrfs_path *path;
struct btrfs_key ins;
u32 size = sizeof(*extent_item) + sizeof(*iref);
u64 start, end;
int ret;
sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
ASSERT(sinfo);
ins.objectid = node->bytenr;
if (skinny_metadata) {
ins.offset = ref->level;
ins.type = BTRFS_METADATA_ITEM_KEY;
} else {
ins.offset = node->num_bytes;
ins.type = BTRFS_EXTENT_ITEM_KEY;
size += sizeof(struct btrfs_tree_block_info);
}
if (ref->root == BTRFS_EXTENT_TREE_OBJECTID) {
ret = find_first_extent_bit(&trans->fs_info->extent_ins,
node->bytenr, &start, &end,
EXTENT_LOCKED);
ASSERT(!ret);
ASSERT(start == node->bytenr);
ASSERT(end == node->bytenr + node->num_bytes - 1);
}
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
&ins, size);
if (ret)
return ret;
leaf = path->nodes[0];
extent_item = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_item);
btrfs_set_extent_refs(leaf, extent_item, 1);
btrfs_set_extent_generation(leaf, extent_item, trans->transid);
btrfs_set_extent_flags(leaf, extent_item,
extent_op->flags_to_set |
BTRFS_EXTENT_FLAG_TREE_BLOCK);
if (skinny_metadata) {
iref = (struct btrfs_extent_inline_ref *)(extent_item + 1);
} else {
struct btrfs_tree_block_info *block_info;
block_info = (struct btrfs_tree_block_info *)(extent_item + 1);
btrfs_set_tree_block_key(leaf, block_info, &extent_op->key);
btrfs_set_tree_block_level(leaf, block_info, ref->level);
iref = (struct btrfs_extent_inline_ref *)(block_info + 1);
}
btrfs_set_extent_inline_ref_type(leaf, iref, BTRFS_TREE_BLOCK_REF_KEY);
btrfs_set_extent_inline_ref_offset(leaf, iref, ref->root);
btrfs_mark_buffer_dirty(leaf);
btrfs_free_path(path);
ret = remove_from_free_space_tree(trans, ins.objectid, fs_info->nodesize);
if (ret)
return ret;
ret = update_block_group(trans, ins.objectid, fs_info->nodesize, 1, 0);
if (sinfo) {
if (fs_info->nodesize > sinfo->bytes_reserved) {
WARN_ON(1);
sinfo->bytes_reserved = 0;
} else {
sinfo->bytes_reserved -= fs_info->nodesize;
}
}
if (ref->root == BTRFS_EXTENT_TREE_OBJECTID) {
clear_extent_bits(&trans->fs_info->extent_ins, start, end,
EXTENT_LOCKED);
}
return ret;
}
static int alloc_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 num_bytes,
u64 root_objectid, u64 generation,
u64 flags, struct btrfs_disk_key *key,
int level, u64 empty_size, u64 hint_byte,
u64 search_end, struct btrfs_key *ins)
{
int ret;
u64 extent_size;
struct btrfs_delayed_extent_op *extent_op;
struct btrfs_space_info *sinfo;
struct btrfs_fs_info *fs_info = root->fs_info;
bool skinny_metadata = btrfs_fs_incompat(root->fs_info,
SKINNY_METADATA);
extent_op = btrfs_alloc_delayed_extent_op();
if (!extent_op)
return -ENOMEM;
sinfo = __find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
if (!sinfo) {
error("Corrupted fs, no valid METADATA block group found");
return -EUCLEAN;
}
ret = btrfs_reserve_extent(trans, root, num_bytes, empty_size,
hint_byte, search_end, ins, 0);
if (ret < 0)
return ret;
if (key)
memcpy(&extent_op->key, key, sizeof(extent_op->key));
else
memset(&extent_op->key, 0, sizeof(extent_op->key));
extent_op->flags_to_set = flags;
extent_op->update_key = skinny_metadata ? false : true;
extent_op->update_flags = true;
extent_op->is_data = false;
extent_op->level = level;
extent_size = ins->offset;
if (btrfs_fs_incompat(root->fs_info, SKINNY_METADATA)) {
ins->offset = level;
ins->type = BTRFS_METADATA_ITEM_KEY;
}
/* Ensure this reserved extent is not found by the allocator */
if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID) {
ret = set_extent_bits(&trans->fs_info->extent_ins,
ins->objectid,
ins->objectid + extent_size - 1,
EXTENT_LOCKED);
BUG_ON(ret);
}
sinfo->bytes_reserved += extent_size;
ret = btrfs_add_delayed_tree_ref(root->fs_info, trans, ins->objectid,
extent_size, 0, root_objectid,
level, BTRFS_ADD_DELAYED_EXTENT,
extent_op, NULL, NULL);
return ret;
}
/*
* helper function to allocate a block for a given tree
* returns the tree buffer or NULL.
*/
struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u32 blocksize, u64 root_objectid,
struct btrfs_disk_key *key, int level,
u64 hint, u64 empty_size)
{
struct btrfs_key ins;
int ret;
struct extent_buffer *buf;
ret = alloc_tree_block(trans, root, blocksize, root_objectid,
trans->transid, 0, key, level,
empty_size, hint, (u64)-1, &ins);
if (ret) {
BUG_ON(ret > 0);
return ERR_PTR(ret);
}
buf = btrfs_find_create_tree_block(root->fs_info, ins.objectid);
if (!buf) {
btrfs_free_extent(trans, root, ins.objectid, ins.offset,
0, root->root_key.objectid, level, 0);
BUG_ON(1);
return ERR_PTR(-ENOMEM);
}
btrfs_set_buffer_uptodate(buf);
trans->blocks_used++;
return buf;
}
int btrfs_free_block_groups(struct btrfs_fs_info *info)
{
struct btrfs_space_info *sinfo;
struct btrfs_block_group *cache, *next;
u64 start;
u64 end;
int ret;
rbtree_postorder_for_each_entry_safe(cache, next,
&info->block_group_cache_tree, cache_node) {
if (!list_empty(&cache->dirty_list))
list_del_init(&cache->dirty_list);
RB_CLEAR_NODE(&cache->cache_node);
if (cache->free_space_ctl) {
btrfs_remove_free_space_cache(cache);
kfree(cache->free_space_ctl);
}
kfree(cache);
}
while(1) {
ret = find_first_extent_bit(&info->free_space_cache, 0,
&start, &end, EXTENT_DIRTY);
if (ret)
break;
clear_extent_dirty(&info->free_space_cache, start, end);
}
while (!list_empty(&info->space_info)) {
sinfo = list_entry(info->space_info.next,
struct btrfs_space_info, list);
list_del_init(&sinfo->list);
if (sinfo->bytes_reserved)
warning(
"reserved space leaked, flag=0x%llx bytes_reserved=%llu",
sinfo->flags, sinfo->bytes_reserved);
kfree(sinfo);
}
return 0;
}
/*
* Find a block group which starts >= @key->objectid in extent tree.
*
* Return 0 for found
* Return >0 for not found
* Return <0 for error
*/
static int find_first_block_group(struct btrfs_root *root,
struct btrfs_path *path, struct btrfs_key *key)
{
int ret;
struct btrfs_key found_key;
struct extent_buffer *leaf;
int slot;
ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
if (ret < 0)
return ret;
while(1) {
slot = path->slots[0];
leaf = path->nodes[0];
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
if (ret < 0)
goto error;
break;
}
btrfs_item_key_to_cpu(leaf, &found_key, slot);
if (found_key.objectid >= key->objectid &&
found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY)
return 0;
path->slots[0]++;
}
ret = 1;
error:
return ret;
}
static int read_block_group_item(struct btrfs_block_group *cache,
struct btrfs_path *path,
const struct btrfs_key *key)
{
struct extent_buffer *leaf = path->nodes[0];
struct btrfs_block_group_item bgi;
int slot = path->slots[0];
ASSERT(key->type == BTRFS_BLOCK_GROUP_ITEM_KEY);
cache->start = key->objectid;
cache->length = key->offset;
read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
sizeof(bgi));
cache->used = btrfs_stack_block_group_used(&bgi);
cache->flags = btrfs_stack_block_group_flags(&bgi);
return 0;
}
/*
* Read out one BLOCK_GROUP_ITEM and insert it into block group cache.
*
* Return 0 if nothing wrong (either insert the bg cache or skip 0 sized bg)
* Return <0 for error.
*/
static int read_one_block_group(struct btrfs_fs_info *fs_info,
struct btrfs_path *path)
{
struct extent_buffer *leaf = path->nodes[0];
struct btrfs_space_info *space_info;
struct btrfs_block_group *cache;
struct btrfs_key key;
int slot = path->slots[0];
int ret;
btrfs_item_key_to_cpu(leaf, &key, slot);
ASSERT(key.type == BTRFS_BLOCK_GROUP_ITEM_KEY);
/*
* Skip 0 sized block group, don't insert them into block group cache
* tree, as its length is 0, it won't get freed at close_ctree() time.
*/
if (key.offset == 0)
return 0;
cache = kzalloc(sizeof(*cache), GFP_NOFS);
if (!cache)
return -ENOMEM;
ret = read_block_group_item(cache, path, &key);
if (ret < 0) {
free(cache);
return ret;
}
INIT_LIST_HEAD(&cache->dirty_list);
set_avail_alloc_bits(fs_info, cache->flags);
ret = btrfs_chunk_readonly(fs_info, cache->start);
if (ret < 0) {
free(cache);
return ret;
}
if (ret)
cache->ro = 1;
exclude_super_stripes(fs_info, cache);
ret = update_space_info(fs_info, cache->flags, cache->length,
cache->used, &space_info);
if (ret < 0) {
free(cache);
return ret;
}
cache->space_info = space_info;
btrfs_add_block_group_cache(fs_info, cache);
return 0;
}
int btrfs_read_block_groups(struct btrfs_fs_info *fs_info)
{
struct btrfs_path path;
struct btrfs_root *root;
int ret;
struct btrfs_key key;
root = fs_info->extent_root;
key.objectid = 0;
key.offset = 0;
key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
btrfs_init_path(&path);
while(1) {
ret = find_first_block_group(root, &path, &key);
if (ret > 0) {
ret = 0;
goto error;
}
if (ret != 0) {
goto error;
}
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
ret = read_one_block_group(fs_info, &path);
if (ret < 0 && ret != -ENOENT)
goto error;
if (key.offset == 0)
key.objectid++;
else
key.objectid = key.objectid + key.offset;
key.offset = 0;
btrfs_release_path(&path);
}
ret = 0;
error:
btrfs_release_path(&path);
return ret;
}
struct btrfs_block_group *
btrfs_add_block_group(struct btrfs_fs_info *fs_info, u64 bytes_used, u64 type,
u64 chunk_offset, u64 size)
{
int ret;
struct btrfs_block_group *cache;
cache = kzalloc(sizeof(*cache), GFP_NOFS);
BUG_ON(!cache);
cache->start = chunk_offset;
cache->length = size;
cache->used = bytes_used;
cache->flags = type;
INIT_LIST_HEAD(&cache->dirty_list);
exclude_super_stripes(fs_info, cache);
ret = update_space_info(fs_info, cache->flags, size, bytes_used,
&cache->space_info);
BUG_ON(ret);
ret = btrfs_add_block_group_cache(fs_info, cache);
BUG_ON(ret);
set_avail_alloc_bits(fs_info, type);
return cache;
}
int btrfs_make_block_group(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytes_used,
u64 type, u64 chunk_offset, u64 size)
{
int ret;
struct btrfs_root *extent_root = fs_info->extent_root;
struct btrfs_block_group *cache;
struct btrfs_block_group_item bgi;
struct btrfs_key key;
cache = btrfs_add_block_group(fs_info, bytes_used, type, chunk_offset,
size);
btrfs_set_stack_block_group_used(&bgi, cache->used);
btrfs_set_stack_block_group_flags(&bgi, cache->flags);
btrfs_set_stack_block_group_chunk_objectid(&bgi,
BTRFS_FIRST_CHUNK_TREE_OBJECTID);
key.objectid = cache->start;
key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
key.offset = cache->length;
ret = btrfs_insert_item(trans, extent_root, &key, &bgi, sizeof(bgi));
BUG_ON(ret);
return 0;
}
static int insert_block_group_item(struct btrfs_trans_handle *trans,
struct btrfs_block_group *block_group)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_block_group_item bgi;
struct btrfs_root *root;
struct btrfs_key key;
btrfs_set_stack_block_group_used(&bgi, block_group->used);
btrfs_set_stack_block_group_chunk_objectid(&bgi,
BTRFS_FIRST_CHUNK_TREE_OBJECTID);
btrfs_set_stack_block_group_flags(&bgi, block_group->flags);
key.objectid = block_group->start;
key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
key.offset = block_group->length;
root = fs_info->extent_root;
return btrfs_insert_item(trans, root, &key, &bgi, sizeof(bgi));
}
/*
* This is for converter use only.
*
* In that case, we don't know where are free blocks located.
* Therefore all block group cache entries must be setup properly
* before doing any block allocation.
*/
int btrfs_make_block_groups(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
u64 total_bytes;
u64 cur_start;
u64 group_type;
u64 group_size;
u64 group_align;
u64 total_data = 0;
u64 total_metadata = 0;
int ret;
struct btrfs_block_group *cache;
total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
group_align = 64 * fs_info->sectorsize;
cur_start = 0;
while (cur_start < total_bytes) {
group_size = total_bytes / 12;
group_size = min_t(u64, group_size, total_bytes - cur_start);
if (cur_start == 0) {
group_type = BTRFS_BLOCK_GROUP_SYSTEM;
group_size /= 4;
group_size &= ~(group_align - 1);
group_size = max_t(u64, group_size, SZ_8M);
group_size = min_t(u64, group_size, SZ_32M);
} else {
group_size &= ~(group_align - 1);
if (total_data >= total_metadata * 2) {
group_type = BTRFS_BLOCK_GROUP_METADATA;
group_size = min_t(u64, group_size, SZ_1G);
total_metadata += group_size;
} else {
group_type = BTRFS_BLOCK_GROUP_DATA;
group_size = min_t(u64, group_size,
5ULL * SZ_1G);
total_data += group_size;
}
if ((total_bytes - cur_start) * 4 < group_size * 5)
group_size = total_bytes - cur_start;
}
cache = kzalloc(sizeof(*cache), GFP_NOFS);
BUG_ON(!cache);
cache->start = cur_start;
cache->length = group_size;
cache->used = 0;
cache->flags = group_type;
INIT_LIST_HEAD(&cache->dirty_list);
ret = update_space_info(fs_info, group_type, group_size,
0, &cache->space_info);
BUG_ON(ret);
set_avail_alloc_bits(fs_info, group_type);
btrfs_add_block_group_cache(fs_info, cache);
cur_start += group_size;
}
/* then insert all the items */
cur_start = 0;
while(cur_start < total_bytes) {
cache = btrfs_lookup_block_group(fs_info, cur_start);
BUG_ON(!cache);
ret = insert_block_group_item(trans, cache);
BUG_ON(ret);
cur_start = cache->start + cache->length;
}
return 0;
}
int btrfs_update_block_group(struct btrfs_trans_handle *trans,
u64 bytenr, u64 num_bytes, int alloc,
int mark_free)
{
return update_block_group(trans, bytenr, num_bytes, alloc, mark_free);
}
/*
* Just remove a block group item in extent tree
* Caller should ensure the block group is empty and all space is pinned.
* Or new tree block/data may be allocated into it.
*/
static int remove_block_group_item(struct btrfs_trans_handle *trans,
struct btrfs_path *path,
struct btrfs_block_group *block_group)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_key key;
struct btrfs_root *root = fs_info->extent_root;
int ret = 0;
key.objectid = block_group->start;
key.offset = block_group->length;
key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0)
ret = -ENOENT;
if (ret < 0)
return ret;
return btrfs_del_item(trans, root, path);
}
static int free_dev_extent_item(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
u64 devid, u64 dev_offset)
{
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_path *path;
struct btrfs_key key;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = devid;
key.type = BTRFS_DEV_EXTENT_KEY;
key.offset = dev_offset;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret < 0)
goto out;
if (ret > 0) {
ret = -ENOENT;
goto out;
}
ret = btrfs_del_item(trans, root, path);
out:
btrfs_free_path(path);
return ret;
}
static int free_chunk_dev_extent_items(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
u64 chunk_offset)
{
struct btrfs_chunk *chunk = NULL;
struct btrfs_root *root= fs_info->chunk_root;
struct btrfs_path *path;
struct btrfs_key key;
u16 num_stripes;
int i;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.type = BTRFS_CHUNK_ITEM_KEY;
key.offset = chunk_offset;
ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
if (ret < 0)
goto out;
if (ret > 0) {
ret = -ENOENT;
goto out;
}
chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_chunk);
num_stripes = btrfs_chunk_num_stripes(path->nodes[0], chunk);
for (i = 0; i < num_stripes; i++) {
ret = free_dev_extent_item(trans, fs_info,
btrfs_stripe_devid_nr(path->nodes[0], chunk, i),
btrfs_stripe_offset_nr(path->nodes[0], chunk, i));
if (ret < 0)
goto out;
}
out:
btrfs_free_path(path);
return ret;
}
static int free_system_chunk_item(struct btrfs_super_block *super,
struct btrfs_key *key)
{
struct btrfs_disk_key *disk_key;
struct btrfs_key cpu_key;
u32 array_size = btrfs_super_sys_array_size(super);
char *ptr = (char *)super->sys_chunk_array;
int cur = 0;
int ret = -ENOENT;
while (cur < btrfs_super_sys_array_size(super)) {
struct btrfs_chunk *chunk;
u32 num_stripes;
u32 chunk_len;
disk_key = (struct btrfs_disk_key *)(ptr + cur);
btrfs_disk_key_to_cpu(&cpu_key, disk_key);
if (cpu_key.type != BTRFS_CHUNK_ITEM_KEY) {
/* just in case */
ret = -EIO;
goto out;
}
chunk = (struct btrfs_chunk *)(ptr + cur + sizeof(*disk_key));
num_stripes = btrfs_stack_chunk_num_stripes(chunk);
chunk_len = btrfs_chunk_item_size(num_stripes) +
sizeof(*disk_key);
if (key->objectid == cpu_key.objectid &&
key->offset == cpu_key.offset &&
key->type == cpu_key.type) {
memmove(ptr + cur, ptr + cur + chunk_len,
array_size - cur - chunk_len);
array_size -= chunk_len;
btrfs_set_super_sys_array_size(super, array_size);
ret = 0;
goto out;
}
cur += chunk_len;
}
out:
return ret;
}
static int free_chunk_item(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
u64 bytenr)
{
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_chunk *chunk;
u64 chunk_type;
int ret;
key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
key.offset = bytenr;
key.type = BTRFS_CHUNK_ITEM_KEY;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0) {
ret = -ENOENT;
goto out;
}
if (ret < 0)
goto out;
chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_chunk);
chunk_type = btrfs_chunk_type(path->nodes[0], chunk);
ret = btrfs_del_item(trans, root, path);
if (ret < 0)
goto out;
if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
ret = free_system_chunk_item(fs_info->super_copy, &key);
out:
btrfs_free_path(path);
return ret;
}
static u64 get_dev_extent_len(struct map_lookup *map)
{
int div;
switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case 0: /* Single */
case BTRFS_BLOCK_GROUP_DUP:
case BTRFS_BLOCK_GROUP_RAID1:
case BTRFS_BLOCK_GROUP_RAID1C3:
case BTRFS_BLOCK_GROUP_RAID1C4:
div = 1;
break;
case BTRFS_BLOCK_GROUP_RAID5:
div = (map->num_stripes - 1);
break;
case BTRFS_BLOCK_GROUP_RAID6:
div = (map->num_stripes - 2);
break;
case BTRFS_BLOCK_GROUP_RAID10:
div = (map->num_stripes / map->sub_stripes);
break;
default:
/* normally, read chunk security hook should handled it */
BUG_ON(1);
}
return map->ce.size / div;
}
/* free block group/chunk related caches */
static int free_block_group_cache(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
u64 bytenr, u64 len)
{
struct btrfs_block_group *cache;
struct cache_extent *ce;
struct map_lookup *map;
int ret;
int i;
u64 flags;
/* Free block group cache first */
cache = btrfs_lookup_block_group(fs_info, bytenr);
if (!cache)
return -ENOENT;
flags = cache->flags;
if (cache->free_space_ctl) {
btrfs_remove_free_space_cache(cache);
kfree(cache->free_space_ctl);
}
if (!list_empty(&cache->dirty_list))
list_del(&cache->dirty_list);
rb_erase(&cache->cache_node, &fs_info->block_group_cache_tree);
ret = free_space_info(fs_info, flags, len, 0, NULL);
if (ret < 0)
goto out;
kfree(cache);
/* Then free mapping info and dev usage info */
ce = search_cache_extent(&fs_info->mapping_tree.cache_tree, bytenr);
if (!ce || ce->start != bytenr) {
ret = -ENOENT;
goto out;
}
map = container_of(ce, struct map_lookup, ce);
for (i = 0; i < map->num_stripes; i++) {
struct btrfs_device *device;
device = map->stripes[i].dev;
device->bytes_used -= get_dev_extent_len(map);
ret = btrfs_update_device(trans, device);
if (ret < 0)
goto out;
}
remove_cache_extent(&fs_info->mapping_tree.cache_tree, ce);
free(map);
out:
return ret;
}
int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
u64 bytenr, u64 len)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_block_group *block_group;
struct btrfs_path path;
int ret = 0;
block_group = btrfs_lookup_block_group(fs_info, bytenr);
if (!block_group || block_group->start != bytenr ||
block_group->length != len)
return -ENOENT;
/* Double check the block group to ensure it's empty */
if (block_group->used) {
fprintf(stderr,
"WARNING: block group [%llu,%llu) is not empty\n",
bytenr, bytenr + len);
return -EUCLEAN;
}
/*
* Now pin all space in the block group, to prevent further transaction
* allocate space from it.
* Every operation needs a transaction must be in the range.
*/
btrfs_pin_extent(fs_info, bytenr, len);
btrfs_init_path(&path);
/* delete block group item and chunk item */
ret = remove_block_group_item(trans, &path, block_group);
btrfs_release_path(&path);
if (ret < 0) {
fprintf(stderr,
"failed to free block group item for [%llu,%llu)\n",
bytenr, bytenr + len);
btrfs_unpin_extent(fs_info, bytenr, len);
return ret;
}
ret = free_chunk_dev_extent_items(trans, fs_info, bytenr);
if (ret < 0) {
fprintf(stderr,
"failed to dev extents belongs to [%llu,%llu)\n",
bytenr, bytenr + len);
btrfs_unpin_extent(fs_info, bytenr, len);
return ret;
}
ret = free_chunk_item(trans, fs_info, bytenr);
if (ret < 0) {
fprintf(stderr,
"failed to free chunk for [%llu,%llu)\n",
bytenr, bytenr + len);
btrfs_unpin_extent(fs_info, bytenr, len);
return ret;
}
/* Now release the block_group_cache */
ret = free_block_group_cache(trans, fs_info, bytenr, len);
btrfs_unpin_extent(fs_info, bytenr, len);
return ret;
}
/*
* Fixup block accounting. The initial block accounting created by
* make_block_groups isn't accuracy in this case.
*/
int btrfs_fix_block_accounting(struct btrfs_trans_handle *trans)
{
int ret = 0;
int slot;
u64 start = 0;
u64 bytes_used = 0;
struct btrfs_path path;
struct btrfs_key key;
struct extent_buffer *leaf;
struct btrfs_block_group *cache;
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_root *root = fs_info->extent_root;
ret = btrfs_run_delayed_refs(trans, -1);
if (ret)
return ret;
while(1) {
cache = btrfs_lookup_first_block_group(fs_info, start);
if (!cache)
break;
start = cache->start + cache->length;
cache->used = 0;
cache->space_info->bytes_used = 0;
if (list_empty(&cache->dirty_list))
list_add_tail(&cache->dirty_list, &trans->dirty_bgs);
}
btrfs_init_path(&path);
key.offset = 0;
key.objectid = 0;
key.type = BTRFS_EXTENT_ITEM_KEY;
ret = btrfs_search_slot(trans, root->fs_info->extent_root,
&key, &path, 0, 0);
if (ret < 0)
return ret;
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)
return ret;
if (ret > 0)
break;
leaf = path.nodes[0];
slot = path.slots[0];
}
btrfs_item_key_to_cpu(leaf, &key, slot);
if (key.type == BTRFS_EXTENT_ITEM_KEY) {
bytes_used += key.offset;
ret = btrfs_update_block_group(trans,
key.objectid, key.offset, 1, 0);
BUG_ON(ret);
} else if (key.type == BTRFS_METADATA_ITEM_KEY) {
bytes_used += fs_info->nodesize;
ret = btrfs_update_block_group(trans,
key.objectid, fs_info->nodesize, 1, 0);
if (ret)
goto out;
}
path.slots[0]++;
}
btrfs_set_super_bytes_used(root->fs_info->super_copy, bytes_used);
ret = 0;
out:
btrfs_release_path(&path);
return ret;
}
static void __get_extent_size(struct btrfs_root *root, struct btrfs_path *path,
u64 *start, u64 *len)
{
struct btrfs_key key;
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
BUG_ON(!(key.type == BTRFS_EXTENT_ITEM_KEY ||
key.type == BTRFS_METADATA_ITEM_KEY));
*start = key.objectid;
if (key.type == BTRFS_EXTENT_ITEM_KEY)
*len = key.offset;
else
*len = root->fs_info->nodesize;
}
/*
* Find first overlap extent for range [bytenr, bytenr + len)
* Return 0 for found and point path to it.
* Return >0 for not found.
* Return <0 for err
*/
static int btrfs_search_overlap_extent(struct btrfs_root *root,
struct btrfs_path *path, u64 bytenr, u64 len)
{
struct btrfs_key key;
u64 cur_start;
u64 cur_len;
int ret;
key.objectid = bytenr;
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
return ret;
BUG_ON(ret == 0);
ret = btrfs_previous_extent_item(root, path, 0);
if (ret < 0)
return ret;
/* no previous, check next extent */
if (ret > 0)
goto next;
__get_extent_size(root, path, &cur_start, &cur_len);
/* Tail overlap */
if (cur_start + cur_len > bytenr)
return 1;
next:
ret = btrfs_next_extent_item(root, path, bytenr + len);
if (ret < 0)
return ret;
/* No next, prev already checked, no overlap */
if (ret > 0)
return 0;
__get_extent_size(root, path, &cur_start, &cur_len);
/* head overlap*/
if (cur_start < bytenr + len)
return 1;
return 0;
}
static int __btrfs_record_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *inode,
u64 file_pos, u64 disk_bytenr,
u64 *ret_num_bytes)
{
int ret;
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_root *extent_root = info->extent_root;
struct extent_buffer *leaf;
struct btrfs_file_extent_item *fi;
struct btrfs_key ins_key;
struct btrfs_path *path;
struct btrfs_extent_item *ei;
u64 nbytes;
u64 extent_num_bytes;
u64 extent_bytenr;
u64 extent_offset;
u64 num_bytes = *ret_num_bytes;
/*
* All supported file system should not use its 0 extent.
* As it's for hole
*
* And hole extent has no size limit, no need to loop.
*/
if (disk_bytenr == 0) {
ret = btrfs_insert_file_extent(trans, root, objectid,
file_pos, disk_bytenr,
num_bytes, num_bytes);
return ret;
}
num_bytes = min_t(u64, num_bytes, BTRFS_MAX_EXTENT_SIZE);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
/* First to check extent overlap */
ret = btrfs_search_overlap_extent(extent_root, path, disk_bytenr,
num_bytes);
if (ret < 0)
goto fail;
if (ret > 0) {
/* Found overlap */
u64 cur_start;
u64 cur_len;
__get_extent_size(extent_root, path, &cur_start, &cur_len);
/*
* For convert case, this extent should be a subset of
* existing one.
*/
BUG_ON(disk_bytenr < cur_start);
extent_bytenr = cur_start;
extent_num_bytes = cur_len;
extent_offset = disk_bytenr - extent_bytenr;
} else {
/* No overlap, create new extent */
btrfs_release_path(path);
ins_key.objectid = disk_bytenr;
ins_key.offset = num_bytes;
ins_key.type = BTRFS_EXTENT_ITEM_KEY;
ret = btrfs_insert_empty_item(trans, extent_root, path,
&ins_key, sizeof(*ei));
if (ret == 0) {
leaf = path->nodes[0];
ei = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_extent_item);
btrfs_set_extent_refs(leaf, ei, 0);
btrfs_set_extent_generation(leaf, ei, 0);
btrfs_set_extent_flags(leaf, ei,
BTRFS_EXTENT_FLAG_DATA);
btrfs_mark_buffer_dirty(leaf);
ret = btrfs_update_block_group(trans, disk_bytenr,
num_bytes, 1, 0);
if (ret)
goto fail;
} else if (ret != -EEXIST) {
goto fail;
}
btrfs_run_delayed_refs(trans, -1);
extent_bytenr = disk_bytenr;
extent_num_bytes = num_bytes;
extent_offset = 0;
}
btrfs_release_path(path);
ins_key.objectid = objectid;
ins_key.offset = file_pos;
ins_key.type = BTRFS_EXTENT_DATA_KEY;
ret = btrfs_insert_empty_item(trans, root, path, &ins_key,
sizeof(*fi));
if (ret)
goto fail;
leaf = path->nodes[0];
fi = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_file_extent_item);
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG);
btrfs_set_file_extent_disk_bytenr(leaf, fi, extent_bytenr);
btrfs_set_file_extent_disk_num_bytes(leaf, fi, extent_num_bytes);
btrfs_set_file_extent_offset(leaf, fi, extent_offset);
btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
btrfs_set_file_extent_ram_bytes(leaf, fi, extent_num_bytes);
btrfs_set_file_extent_compression(leaf, fi, 0);
btrfs_set_file_extent_encryption(leaf, fi, 0);
btrfs_set_file_extent_other_encoding(leaf, fi, 0);
btrfs_mark_buffer_dirty(leaf);
nbytes = btrfs_stack_inode_nbytes(inode) + num_bytes;
btrfs_set_stack_inode_nbytes(inode, nbytes);
btrfs_release_path(path);
ret = btrfs_inc_extent_ref(trans, root, extent_bytenr, extent_num_bytes,
0, root->root_key.objectid, objectid,
file_pos - extent_offset);
if (ret)
goto fail;
ret = 0;
*ret_num_bytes = min(extent_num_bytes - extent_offset, num_bytes);
fail:
btrfs_free_path(path);
return ret;
}
/*
* Record a file extent. Do all the required works, such as inserting
* file extent item, inserting extent item and backref item into extent
* tree and updating block accounting.
*/
int btrfs_record_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid,
struct btrfs_inode_item *inode,
u64 file_pos, u64 disk_bytenr,
u64 num_bytes)
{
u64 cur_disk_bytenr = disk_bytenr;
u64 cur_file_pos = file_pos;
u64 cur_num_bytes = num_bytes;
int ret = 0;
while (num_bytes > 0) {
ret = __btrfs_record_file_extent(trans, root, objectid,
inode, cur_file_pos,
cur_disk_bytenr,
&cur_num_bytes);
if (ret < 0)
break;
cur_disk_bytenr += cur_num_bytes;
cur_file_pos += cur_num_bytes;
num_bytes -= cur_num_bytes;
}
return ret;
}
static int add_excluded_extent(struct btrfs_fs_info *fs_info,
u64 start, u64 num_bytes)
{
u64 end = start + num_bytes - 1;
set_extent_bits(&fs_info->pinned_extents,
start, end, EXTENT_UPTODATE);
return 0;
}
void free_excluded_extents(struct btrfs_fs_info *fs_info,
struct btrfs_block_group *cache)
{
u64 start, end;
start = cache->start;
end = start + cache->length - 1;
clear_extent_bits(&fs_info->pinned_extents,
start, end, EXTENT_UPTODATE);
}
int exclude_super_stripes(struct btrfs_fs_info *fs_info,
struct btrfs_block_group *cache)
{
u64 bytenr;
u64 *logical;
int stripe_len;
int i, nr, ret;
if (cache->start < BTRFS_SUPER_INFO_OFFSET) {
stripe_len = BTRFS_SUPER_INFO_OFFSET - cache->start;
cache->bytes_super += stripe_len;
ret = add_excluded_extent(fs_info, cache->start, stripe_len);
if (ret)
return ret;
}
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
ret = btrfs_rmap_block(fs_info, cache->start, bytenr,
&logical, &nr, &stripe_len);
if (ret)
return ret;
while (nr--) {
u64 start, len;
if (logical[nr] >= cache->start + cache->length)
continue;
if (logical[nr] + stripe_len <= cache->start)
continue;
start = logical[nr];
if (start < cache->start) {
start = cache->start;
len = (logical[nr] + stripe_len) - start;
} else {
len = min_t(u64, stripe_len, cache->start +
cache->length - start);
}
cache->bytes_super += len;
ret = add_excluded_extent(fs_info, start, len);
if (ret) {
kfree(logical);
return ret;
}
}
kfree(logical);
}
return 0;
}
u64 add_new_free_space(struct btrfs_block_group *block_group,
struct btrfs_fs_info *info, u64 start, u64 end)
{
u64 extent_start, extent_end, size, total_added = 0;
int ret;
while (start < end) {
ret = find_first_extent_bit(&info->pinned_extents, start,
&extent_start, &extent_end,
EXTENT_DIRTY | EXTENT_UPTODATE);
if (ret)
break;
if (extent_start <= start) {
start = extent_end + 1;
} else if (extent_start > start && extent_start < end) {
size = extent_start - start;
total_added += size;
ret = btrfs_add_free_space(block_group->free_space_ctl,
start, size);
BUG_ON(ret); /* -ENOMEM or logic error */
start = extent_end + 1;
} else {
break;
}
}
if (start < end) {
size = end - start;
total_added += size;
ret = btrfs_add_free_space(block_group->free_space_ctl, start,
size);
BUG_ON(ret); /* -ENOMEM or logic error */
}
return total_added;
}
static void cleanup_extent_op(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_head *head)
{
struct btrfs_delayed_extent_op *extent_op = head->extent_op;
if (!extent_op)
return;
head->extent_op = NULL;
btrfs_free_delayed_extent_op(extent_op);
}
static void unselect_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
struct btrfs_delayed_ref_head *head)
{
head->processing = 0;
delayed_refs->num_heads_ready++;
}
int cleanup_ref_head(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_head *head)
{
struct btrfs_delayed_ref_root *delayed_refs;
delayed_refs = &trans->delayed_refs;
cleanup_extent_op(trans, fs_info, head);
/*
* Need to drop our head ref lock and re-acquire the delayed ref lock
* and then re-check to make sure nobody got added.
*/
if (!RB_EMPTY_ROOT(&head->ref_tree) || head->extent_op)
return 1;
delayed_refs->num_heads--;
rb_erase(&head->href_node, &delayed_refs->href_root);
RB_CLEAR_NODE(&head->href_node);
if (head->must_insert_reserved) {
btrfs_pin_extent(fs_info, head->bytenr, head->num_bytes);
if (!head->is_data) {
struct btrfs_space_info *sinfo;
sinfo = __find_space_info(trans->fs_info,
BTRFS_BLOCK_GROUP_METADATA);
ASSERT(sinfo);
sinfo->bytes_reserved -= head->num_bytes;
}
}
btrfs_put_delayed_ref_head(head);
return 0;
}
static inline struct btrfs_delayed_ref_node *
select_delayed_ref(struct btrfs_delayed_ref_head *head)
{
struct btrfs_delayed_ref_node *ref;
if (RB_EMPTY_ROOT(&head->ref_tree))
return NULL;
/*
* Select a delayed ref of type BTRFS_ADD_DELAYED_REF first.
* This is to prevent a ref count from going down to zero, which deletes
* the extent item from the extent tree, when there still are references
* to add, which would fail because they would not find the extent item.
*/
if (!list_empty(&head->ref_add_list))
return list_first_entry(&head->ref_add_list,
struct btrfs_delayed_ref_node,
add_list);
ref = rb_entry(rb_first(&head->ref_tree),
struct btrfs_delayed_ref_node, ref_node);
ASSERT(list_empty(&ref->add_list));
return ref;
}
static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_node *node,
struct btrfs_delayed_extent_op *extent_op,
int insert_reserved)
{
int ret = 0;
struct btrfs_delayed_tree_ref *ref;
u64 parent = 0;
u64 ref_root = 0;
ref = btrfs_delayed_node_to_tree_ref(node);
if (node->type == BTRFS_SHARED_BLOCK_REF_KEY)
parent = ref->parent;
ref_root = ref->root;
if (node->ref_mod != 1) {
printf("btree block(%llu) has %d references rather than 1: action %u ref_root %llu parent %llu",
node->bytenr, node->ref_mod, node->action, ref_root,
parent);
return -EIO;
}
if (node->action == BTRFS_ADD_DELAYED_REF && insert_reserved) {
BUG_ON(!extent_op || !extent_op->update_flags);
ret = alloc_reserved_tree_block(trans, node, extent_op);
} else if (node->action == BTRFS_DROP_DELAYED_REF) {
struct btrfs_delayed_tree_ref *ref = btrfs_delayed_node_to_tree_ref(node);
ret = __free_extent(trans, node->bytenr, node->num_bytes,
ref->parent, ref->root, ref->level, 0, 1);
} else {
BUG();
}
return ret;
}
/* helper function to actually process a single delayed ref entry */
static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_node *node,
struct btrfs_delayed_extent_op *extent_op,
int insert_reserved)
{
int ret = 0;
if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
node->type == BTRFS_SHARED_BLOCK_REF_KEY) {
ret = run_delayed_tree_ref(trans, fs_info, node, extent_op,
insert_reserved);
} else
BUG();
return ret;
}
int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans, unsigned long nr)
{
struct btrfs_fs_info *fs_info = trans->fs_info;
struct btrfs_delayed_ref_root *delayed_refs;
struct btrfs_delayed_ref_node *ref;
struct btrfs_delayed_ref_head *locked_ref = NULL;
struct btrfs_delayed_extent_op *extent_op;
int ret;
int must_insert_reserved = 0;
delayed_refs = &trans->delayed_refs;
while (1) {
if (!locked_ref) {
locked_ref = btrfs_select_ref_head(trans);
if (!locked_ref)
break;
}
/*
* We need to try and merge add/drops of the same ref since we
* can run into issues with relocate dropping the implicit ref
* and then it being added back again before the drop can
* finish. If we merged anything we need to re-loop so we can
* get a good ref.
* Or we can get node references of the same type that weren't
* merged when created due to bumps in the tree mod seq, and
* we need to merge them to prevent adding an inline extent
* backref before dropping it (triggering a BUG_ON at
* insert_inline_extent_backref()).
*/
btrfs_merge_delayed_refs(trans, delayed_refs, locked_ref);
ref = select_delayed_ref(locked_ref);
/*
* We're done processing refs in this ref_head, clean everything
* up and move on to the next ref_head.
*/
if (!ref) {
ret = cleanup_ref_head(trans, fs_info, locked_ref);
if (ret > 0 ) {
/* We dropped our lock, we need to loop. */
ret = 0;
continue;
}
locked_ref = NULL;
continue;
}
ref->in_tree = 0;
rb_erase(&ref->ref_node, &locked_ref->ref_tree);
RB_CLEAR_NODE(&ref->ref_node);
if (!list_empty(&ref->add_list))
list_del(&ref->add_list);
/*
* When we play the delayed ref, also correct the ref_mod on
* head
*/
switch (ref->action) {
case BTRFS_ADD_DELAYED_REF:
case BTRFS_ADD_DELAYED_EXTENT:
locked_ref->ref_mod -= ref->ref_mod;
break;
case BTRFS_DROP_DELAYED_REF:
locked_ref->ref_mod += ref->ref_mod;
break;
default:
WARN_ON(1);
}
/*
* Record the must-insert_reserved flag before we drop the spin
* lock.
*/
must_insert_reserved = locked_ref->must_insert_reserved;
locked_ref->must_insert_reserved = 0;
extent_op = locked_ref->extent_op;
locked_ref->extent_op = NULL;
ret = run_one_delayed_ref(trans, fs_info, ref, extent_op,
must_insert_reserved);
btrfs_free_delayed_extent_op(extent_op);
/*
* If we are re-initing extent tree in this transaction
* failure in freeing old roots are expected (because we don't
* have the old extent tree, hence backref resolution will
* return -EIO).
*/
if (ret && (!trans->reinit_extent_tree ||
ref->action != BTRFS_DROP_DELAYED_REF)) {
unselect_delayed_ref_head(delayed_refs, locked_ref);
btrfs_put_delayed_ref(ref);
return ret;
}
btrfs_put_delayed_ref(ref);
}
return 0;
}
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