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![Filipe Manana](/assets/img/avatar_default.png)
Since add_new_free_space() is exported, used outside block-group.c, rename it to include the 'btrfs_' prefix. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
1666 lines
42 KiB
C
1666 lines
42 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2015 Facebook. All rights reserved.
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*/
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#include <linux/kernel.h>
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#include <linux/sched/mm.h>
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#include "messages.h"
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#include "ctree.h"
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#include "disk-io.h"
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#include "locking.h"
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#include "free-space-tree.h"
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#include "transaction.h"
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#include "block-group.h"
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#include "fs.h"
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#include "accessors.h"
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#include "extent-tree.h"
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#include "root-tree.h"
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static int __add_block_group_free_space(struct btrfs_trans_handle *trans,
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struct btrfs_block_group *block_group,
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struct btrfs_path *path);
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static struct btrfs_root *btrfs_free_space_root(
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struct btrfs_block_group *block_group)
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{
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struct btrfs_key key = {
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.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID,
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.type = BTRFS_ROOT_ITEM_KEY,
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.offset = 0,
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};
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if (btrfs_fs_incompat(block_group->fs_info, EXTENT_TREE_V2))
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key.offset = block_group->global_root_id;
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return btrfs_global_root(block_group->fs_info, &key);
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}
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void set_free_space_tree_thresholds(struct btrfs_block_group *cache)
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{
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u32 bitmap_range;
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size_t bitmap_size;
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u64 num_bitmaps, total_bitmap_size;
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if (WARN_ON(cache->length == 0))
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btrfs_warn(cache->fs_info, "block group %llu length is zero",
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cache->start);
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/*
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* We convert to bitmaps when the disk space required for using extents
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* exceeds that required for using bitmaps.
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*/
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bitmap_range = cache->fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS;
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num_bitmaps = div_u64(cache->length + bitmap_range - 1, bitmap_range);
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bitmap_size = sizeof(struct btrfs_item) + BTRFS_FREE_SPACE_BITMAP_SIZE;
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total_bitmap_size = num_bitmaps * bitmap_size;
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cache->bitmap_high_thresh = div_u64(total_bitmap_size,
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sizeof(struct btrfs_item));
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/*
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* We allow for a small buffer between the high threshold and low
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* threshold to avoid thrashing back and forth between the two formats.
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*/
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if (cache->bitmap_high_thresh > 100)
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cache->bitmap_low_thresh = cache->bitmap_high_thresh - 100;
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else
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cache->bitmap_low_thresh = 0;
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}
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static int add_new_free_space_info(struct btrfs_trans_handle *trans,
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struct btrfs_block_group *block_group,
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struct btrfs_path *path)
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{
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struct btrfs_root *root = btrfs_free_space_root(block_group);
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struct btrfs_free_space_info *info;
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struct btrfs_key key;
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struct extent_buffer *leaf;
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int ret;
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key.objectid = block_group->start;
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key.type = BTRFS_FREE_SPACE_INFO_KEY;
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key.offset = block_group->length;
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ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*info));
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if (ret)
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goto out;
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leaf = path->nodes[0];
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info = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_free_space_info);
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btrfs_set_free_space_extent_count(leaf, info, 0);
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btrfs_set_free_space_flags(leaf, info, 0);
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btrfs_mark_buffer_dirty(leaf);
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ret = 0;
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out:
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btrfs_release_path(path);
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return ret;
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}
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EXPORT_FOR_TESTS
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struct btrfs_free_space_info *search_free_space_info(
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struct btrfs_trans_handle *trans,
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struct btrfs_block_group *block_group,
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struct btrfs_path *path, int cow)
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{
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struct btrfs_fs_info *fs_info = block_group->fs_info;
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struct btrfs_root *root = btrfs_free_space_root(block_group);
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struct btrfs_key key;
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int ret;
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key.objectid = block_group->start;
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key.type = BTRFS_FREE_SPACE_INFO_KEY;
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key.offset = block_group->length;
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ret = btrfs_search_slot(trans, root, &key, path, 0, cow);
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if (ret < 0)
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return ERR_PTR(ret);
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if (ret != 0) {
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btrfs_warn(fs_info, "missing free space info for %llu",
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block_group->start);
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ASSERT(0);
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return ERR_PTR(-ENOENT);
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}
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return btrfs_item_ptr(path->nodes[0], path->slots[0],
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struct btrfs_free_space_info);
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}
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/*
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* btrfs_search_slot() but we're looking for the greatest key less than the
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* passed key.
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*/
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static int btrfs_search_prev_slot(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct btrfs_key *key, struct btrfs_path *p,
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int ins_len, int cow)
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{
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int ret;
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ret = btrfs_search_slot(trans, root, key, p, ins_len, cow);
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if (ret < 0)
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return ret;
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if (ret == 0) {
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ASSERT(0);
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return -EIO;
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}
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if (p->slots[0] == 0) {
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ASSERT(0);
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return -EIO;
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}
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p->slots[0]--;
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return 0;
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}
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static inline u32 free_space_bitmap_size(const struct btrfs_fs_info *fs_info,
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u64 size)
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{
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return DIV_ROUND_UP(size >> fs_info->sectorsize_bits, BITS_PER_BYTE);
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}
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static unsigned long *alloc_bitmap(u32 bitmap_size)
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{
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unsigned long *ret;
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unsigned int nofs_flag;
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u32 bitmap_rounded_size = round_up(bitmap_size, sizeof(unsigned long));
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/*
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* GFP_NOFS doesn't work with kvmalloc(), but we really can't recurse
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* into the filesystem as the free space bitmap can be modified in the
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* critical section of a transaction commit.
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*
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* TODO: push the memalloc_nofs_{save,restore}() to the caller where we
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* know that recursion is unsafe.
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*/
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nofs_flag = memalloc_nofs_save();
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ret = kvzalloc(bitmap_rounded_size, GFP_KERNEL);
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memalloc_nofs_restore(nofs_flag);
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return ret;
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}
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static void le_bitmap_set(unsigned long *map, unsigned int start, int len)
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{
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u8 *p = ((u8 *)map) + BIT_BYTE(start);
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const unsigned int size = start + len;
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int bits_to_set = BITS_PER_BYTE - (start % BITS_PER_BYTE);
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u8 mask_to_set = BITMAP_FIRST_BYTE_MASK(start);
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while (len - bits_to_set >= 0) {
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*p |= mask_to_set;
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len -= bits_to_set;
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bits_to_set = BITS_PER_BYTE;
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mask_to_set = ~0;
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p++;
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}
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if (len) {
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mask_to_set &= BITMAP_LAST_BYTE_MASK(size);
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*p |= mask_to_set;
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}
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}
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EXPORT_FOR_TESTS
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int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans,
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struct btrfs_block_group *block_group,
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struct btrfs_path *path)
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{
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struct btrfs_fs_info *fs_info = trans->fs_info;
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struct btrfs_root *root = btrfs_free_space_root(block_group);
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struct btrfs_free_space_info *info;
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struct btrfs_key key, found_key;
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struct extent_buffer *leaf;
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unsigned long *bitmap;
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char *bitmap_cursor;
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u64 start, end;
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u64 bitmap_range, i;
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u32 bitmap_size, flags, expected_extent_count;
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u32 extent_count = 0;
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int done = 0, nr;
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int ret;
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bitmap_size = free_space_bitmap_size(fs_info, block_group->length);
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bitmap = alloc_bitmap(bitmap_size);
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if (!bitmap) {
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ret = -ENOMEM;
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goto out;
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}
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start = block_group->start;
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end = block_group->start + block_group->length;
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key.objectid = end - 1;
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key.type = (u8)-1;
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key.offset = (u64)-1;
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while (!done) {
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ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1);
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if (ret)
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goto out;
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leaf = path->nodes[0];
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nr = 0;
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path->slots[0]++;
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while (path->slots[0] > 0) {
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btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1);
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if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) {
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ASSERT(found_key.objectid == block_group->start);
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ASSERT(found_key.offset == block_group->length);
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done = 1;
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break;
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} else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY) {
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u64 first, last;
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ASSERT(found_key.objectid >= start);
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ASSERT(found_key.objectid < end);
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ASSERT(found_key.objectid + found_key.offset <= end);
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first = div_u64(found_key.objectid - start,
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fs_info->sectorsize);
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last = div_u64(found_key.objectid + found_key.offset - start,
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fs_info->sectorsize);
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le_bitmap_set(bitmap, first, last - first);
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extent_count++;
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nr++;
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path->slots[0]--;
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} else {
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ASSERT(0);
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}
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}
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ret = btrfs_del_items(trans, root, path, path->slots[0], nr);
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if (ret)
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goto out;
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btrfs_release_path(path);
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}
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info = search_free_space_info(trans, block_group, path, 1);
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if (IS_ERR(info)) {
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ret = PTR_ERR(info);
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goto out;
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}
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leaf = path->nodes[0];
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flags = btrfs_free_space_flags(leaf, info);
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flags |= BTRFS_FREE_SPACE_USING_BITMAPS;
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btrfs_set_free_space_flags(leaf, info, flags);
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expected_extent_count = btrfs_free_space_extent_count(leaf, info);
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btrfs_mark_buffer_dirty(leaf);
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btrfs_release_path(path);
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if (extent_count != expected_extent_count) {
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btrfs_err(fs_info,
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"incorrect extent count for %llu; counted %u, expected %u",
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block_group->start, extent_count,
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expected_extent_count);
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ASSERT(0);
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ret = -EIO;
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goto out;
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}
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bitmap_cursor = (char *)bitmap;
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bitmap_range = fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS;
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i = start;
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while (i < end) {
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unsigned long ptr;
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u64 extent_size;
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u32 data_size;
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extent_size = min(end - i, bitmap_range);
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data_size = free_space_bitmap_size(fs_info, extent_size);
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key.objectid = i;
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key.type = BTRFS_FREE_SPACE_BITMAP_KEY;
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key.offset = extent_size;
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ret = btrfs_insert_empty_item(trans, root, path, &key,
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data_size);
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if (ret)
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goto out;
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leaf = path->nodes[0];
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ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
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write_extent_buffer(leaf, bitmap_cursor, ptr,
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data_size);
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btrfs_mark_buffer_dirty(leaf);
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btrfs_release_path(path);
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i += extent_size;
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bitmap_cursor += data_size;
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}
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ret = 0;
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out:
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kvfree(bitmap);
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if (ret)
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btrfs_abort_transaction(trans, ret);
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return ret;
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}
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EXPORT_FOR_TESTS
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int convert_free_space_to_extents(struct btrfs_trans_handle *trans,
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struct btrfs_block_group *block_group,
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struct btrfs_path *path)
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{
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struct btrfs_fs_info *fs_info = trans->fs_info;
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struct btrfs_root *root = btrfs_free_space_root(block_group);
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struct btrfs_free_space_info *info;
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struct btrfs_key key, found_key;
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struct extent_buffer *leaf;
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unsigned long *bitmap;
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u64 start, end;
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u32 bitmap_size, flags, expected_extent_count;
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unsigned long nrbits, start_bit, end_bit;
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u32 extent_count = 0;
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int done = 0, nr;
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int ret;
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bitmap_size = free_space_bitmap_size(fs_info, block_group->length);
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bitmap = alloc_bitmap(bitmap_size);
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if (!bitmap) {
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ret = -ENOMEM;
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goto out;
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}
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start = block_group->start;
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end = block_group->start + block_group->length;
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key.objectid = end - 1;
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key.type = (u8)-1;
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key.offset = (u64)-1;
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while (!done) {
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ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1);
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if (ret)
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goto out;
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leaf = path->nodes[0];
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nr = 0;
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path->slots[0]++;
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while (path->slots[0] > 0) {
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btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1);
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if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) {
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ASSERT(found_key.objectid == block_group->start);
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ASSERT(found_key.offset == block_group->length);
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done = 1;
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break;
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} else if (found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) {
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unsigned long ptr;
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char *bitmap_cursor;
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u32 bitmap_pos, data_size;
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ASSERT(found_key.objectid >= start);
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ASSERT(found_key.objectid < end);
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ASSERT(found_key.objectid + found_key.offset <= end);
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bitmap_pos = div_u64(found_key.objectid - start,
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fs_info->sectorsize *
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BITS_PER_BYTE);
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bitmap_cursor = ((char *)bitmap) + bitmap_pos;
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data_size = free_space_bitmap_size(fs_info,
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found_key.offset);
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ptr = btrfs_item_ptr_offset(leaf, path->slots[0] - 1);
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read_extent_buffer(leaf, bitmap_cursor, ptr,
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data_size);
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nr++;
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path->slots[0]--;
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} else {
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ASSERT(0);
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}
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}
|
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ret = btrfs_del_items(trans, root, path, path->slots[0], nr);
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if (ret)
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goto out;
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btrfs_release_path(path);
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}
|
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info = search_free_space_info(trans, block_group, path, 1);
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if (IS_ERR(info)) {
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ret = PTR_ERR(info);
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goto out;
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}
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leaf = path->nodes[0];
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flags = btrfs_free_space_flags(leaf, info);
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flags &= ~BTRFS_FREE_SPACE_USING_BITMAPS;
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btrfs_set_free_space_flags(leaf, info, flags);
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expected_extent_count = btrfs_free_space_extent_count(leaf, info);
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btrfs_mark_buffer_dirty(leaf);
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btrfs_release_path(path);
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|
|
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nrbits = block_group->length >> block_group->fs_info->sectorsize_bits;
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start_bit = find_next_bit_le(bitmap, nrbits, 0);
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|
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while (start_bit < nrbits) {
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end_bit = find_next_zero_bit_le(bitmap, nrbits, start_bit);
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ASSERT(start_bit < end_bit);
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|
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key.objectid = start + start_bit * block_group->fs_info->sectorsize;
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key.type = BTRFS_FREE_SPACE_EXTENT_KEY;
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key.offset = (end_bit - start_bit) * block_group->fs_info->sectorsize;
|
|
|
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ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
|
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if (ret)
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goto out;
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|
btrfs_release_path(path);
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|
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extent_count++;
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|
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start_bit = find_next_bit_le(bitmap, nrbits, end_bit);
|
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}
|
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|
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if (extent_count != expected_extent_count) {
|
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btrfs_err(fs_info,
|
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"incorrect extent count for %llu; counted %u, expected %u",
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block_group->start, extent_count,
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expected_extent_count);
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ASSERT(0);
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ret = -EIO;
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goto out;
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}
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|
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ret = 0;
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out:
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kvfree(bitmap);
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if (ret)
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btrfs_abort_transaction(trans, ret);
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return ret;
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}
|
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|
|
static int update_free_space_extent_count(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path,
|
|
int new_extents)
|
|
{
|
|
struct btrfs_free_space_info *info;
|
|
u32 flags;
|
|
u32 extent_count;
|
|
int ret = 0;
|
|
|
|
if (new_extents == 0)
|
|
return 0;
|
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|
|
info = search_free_space_info(trans, block_group, path, 1);
|
|
if (IS_ERR(info)) {
|
|
ret = PTR_ERR(info);
|
|
goto out;
|
|
}
|
|
flags = btrfs_free_space_flags(path->nodes[0], info);
|
|
extent_count = btrfs_free_space_extent_count(path->nodes[0], info);
|
|
|
|
extent_count += new_extents;
|
|
btrfs_set_free_space_extent_count(path->nodes[0], info, extent_count);
|
|
btrfs_mark_buffer_dirty(path->nodes[0]);
|
|
btrfs_release_path(path);
|
|
|
|
if (!(flags & BTRFS_FREE_SPACE_USING_BITMAPS) &&
|
|
extent_count > block_group->bitmap_high_thresh) {
|
|
ret = convert_free_space_to_bitmaps(trans, block_group, path);
|
|
} else if ((flags & BTRFS_FREE_SPACE_USING_BITMAPS) &&
|
|
extent_count < block_group->bitmap_low_thresh) {
|
|
ret = convert_free_space_to_extents(trans, block_group, path);
|
|
}
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
EXPORT_FOR_TESTS
|
|
int free_space_test_bit(struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path, u64 offset)
|
|
{
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_key key;
|
|
u64 found_start, found_end;
|
|
unsigned long ptr, i;
|
|
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY);
|
|
|
|
found_start = key.objectid;
|
|
found_end = key.objectid + key.offset;
|
|
ASSERT(offset >= found_start && offset < found_end);
|
|
|
|
ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
|
|
i = div_u64(offset - found_start,
|
|
block_group->fs_info->sectorsize);
|
|
return !!extent_buffer_test_bit(leaf, ptr, i);
|
|
}
|
|
|
|
static void free_space_set_bits(struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path, u64 *start, u64 *size,
|
|
int bit)
|
|
{
|
|
struct btrfs_fs_info *fs_info = block_group->fs_info;
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_key key;
|
|
u64 end = *start + *size;
|
|
u64 found_start, found_end;
|
|
unsigned long ptr, first, last;
|
|
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY);
|
|
|
|
found_start = key.objectid;
|
|
found_end = key.objectid + key.offset;
|
|
ASSERT(*start >= found_start && *start < found_end);
|
|
ASSERT(end > found_start);
|
|
|
|
if (end > found_end)
|
|
end = found_end;
|
|
|
|
ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
|
|
first = (*start - found_start) >> fs_info->sectorsize_bits;
|
|
last = (end - found_start) >> fs_info->sectorsize_bits;
|
|
if (bit)
|
|
extent_buffer_bitmap_set(leaf, ptr, first, last - first);
|
|
else
|
|
extent_buffer_bitmap_clear(leaf, ptr, first, last - first);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
*size -= end - *start;
|
|
*start = end;
|
|
}
|
|
|
|
/*
|
|
* We can't use btrfs_next_item() in modify_free_space_bitmap() because
|
|
* btrfs_next_leaf() doesn't get the path for writing. We can forgo the fancy
|
|
* tree walking in btrfs_next_leaf() anyways because we know exactly what we're
|
|
* looking for.
|
|
*/
|
|
static int free_space_next_bitmap(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root, struct btrfs_path *p)
|
|
{
|
|
struct btrfs_key key;
|
|
|
|
if (p->slots[0] + 1 < btrfs_header_nritems(p->nodes[0])) {
|
|
p->slots[0]++;
|
|
return 0;
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(p->nodes[0], &key, p->slots[0]);
|
|
btrfs_release_path(p);
|
|
|
|
key.objectid += key.offset;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
return btrfs_search_prev_slot(trans, root, &key, p, 0, 1);
|
|
}
|
|
|
|
/*
|
|
* If remove is 1, then we are removing free space, thus clearing bits in the
|
|
* bitmap. If remove is 0, then we are adding free space, thus setting bits in
|
|
* the bitmap.
|
|
*/
|
|
static int modify_free_space_bitmap(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path,
|
|
u64 start, u64 size, int remove)
|
|
{
|
|
struct btrfs_root *root = btrfs_free_space_root(block_group);
|
|
struct btrfs_key key;
|
|
u64 end = start + size;
|
|
u64 cur_start, cur_size;
|
|
int prev_bit, next_bit;
|
|
int new_extents;
|
|
int ret;
|
|
|
|
/*
|
|
* Read the bit for the block immediately before the extent of space if
|
|
* that block is within the block group.
|
|
*/
|
|
if (start > block_group->start) {
|
|
u64 prev_block = start - block_group->fs_info->sectorsize;
|
|
|
|
key.objectid = prev_block;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1);
|
|
if (ret)
|
|
goto out;
|
|
|
|
prev_bit = free_space_test_bit(block_group, path, prev_block);
|
|
|
|
/* The previous block may have been in the previous bitmap. */
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
if (start >= key.objectid + key.offset) {
|
|
ret = free_space_next_bitmap(trans, root, path);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
} else {
|
|
key.objectid = start;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1);
|
|
if (ret)
|
|
goto out;
|
|
|
|
prev_bit = -1;
|
|
}
|
|
|
|
/*
|
|
* Iterate over all of the bitmaps overlapped by the extent of space,
|
|
* clearing/setting bits as required.
|
|
*/
|
|
cur_start = start;
|
|
cur_size = size;
|
|
while (1) {
|
|
free_space_set_bits(block_group, path, &cur_start, &cur_size,
|
|
!remove);
|
|
if (cur_size == 0)
|
|
break;
|
|
ret = free_space_next_bitmap(trans, root, path);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Read the bit for the block immediately after the extent of space if
|
|
* that block is within the block group.
|
|
*/
|
|
if (end < block_group->start + block_group->length) {
|
|
/* The next block may be in the next bitmap. */
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
if (end >= key.objectid + key.offset) {
|
|
ret = free_space_next_bitmap(trans, root, path);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
next_bit = free_space_test_bit(block_group, path, end);
|
|
} else {
|
|
next_bit = -1;
|
|
}
|
|
|
|
if (remove) {
|
|
new_extents = -1;
|
|
if (prev_bit == 1) {
|
|
/* Leftover on the left. */
|
|
new_extents++;
|
|
}
|
|
if (next_bit == 1) {
|
|
/* Leftover on the right. */
|
|
new_extents++;
|
|
}
|
|
} else {
|
|
new_extents = 1;
|
|
if (prev_bit == 1) {
|
|
/* Merging with neighbor on the left. */
|
|
new_extents--;
|
|
}
|
|
if (next_bit == 1) {
|
|
/* Merging with neighbor on the right. */
|
|
new_extents--;
|
|
}
|
|
}
|
|
|
|
btrfs_release_path(path);
|
|
ret = update_free_space_extent_count(trans, block_group, path,
|
|
new_extents);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static int remove_free_space_extent(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path,
|
|
u64 start, u64 size)
|
|
{
|
|
struct btrfs_root *root = btrfs_free_space_root(block_group);
|
|
struct btrfs_key key;
|
|
u64 found_start, found_end;
|
|
u64 end = start + size;
|
|
int new_extents = -1;
|
|
int ret;
|
|
|
|
key.objectid = start;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1);
|
|
if (ret)
|
|
goto out;
|
|
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY);
|
|
|
|
found_start = key.objectid;
|
|
found_end = key.objectid + key.offset;
|
|
ASSERT(start >= found_start && end <= found_end);
|
|
|
|
/*
|
|
* Okay, now that we've found the free space extent which contains the
|
|
* free space that we are removing, there are four cases:
|
|
*
|
|
* 1. We're using the whole extent: delete the key we found and
|
|
* decrement the free space extent count.
|
|
* 2. We are using part of the extent starting at the beginning: delete
|
|
* the key we found and insert a new key representing the leftover at
|
|
* the end. There is no net change in the number of extents.
|
|
* 3. We are using part of the extent ending at the end: delete the key
|
|
* we found and insert a new key representing the leftover at the
|
|
* beginning. There is no net change in the number of extents.
|
|
* 4. We are using part of the extent in the middle: delete the key we
|
|
* found and insert two new keys representing the leftovers on each
|
|
* side. Where we used to have one extent, we now have two, so increment
|
|
* the extent count. We may need to convert the block group to bitmaps
|
|
* as a result.
|
|
*/
|
|
|
|
/* Delete the existing key (cases 1-4). */
|
|
ret = btrfs_del_item(trans, root, path);
|
|
if (ret)
|
|
goto out;
|
|
|
|
/* Add a key for leftovers at the beginning (cases 3 and 4). */
|
|
if (start > found_start) {
|
|
key.objectid = found_start;
|
|
key.type = BTRFS_FREE_SPACE_EXTENT_KEY;
|
|
key.offset = start - found_start;
|
|
|
|
btrfs_release_path(path);
|
|
ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
|
|
if (ret)
|
|
goto out;
|
|
new_extents++;
|
|
}
|
|
|
|
/* Add a key for leftovers at the end (cases 2 and 4). */
|
|
if (end < found_end) {
|
|
key.objectid = end;
|
|
key.type = BTRFS_FREE_SPACE_EXTENT_KEY;
|
|
key.offset = found_end - end;
|
|
|
|
btrfs_release_path(path);
|
|
ret = btrfs_insert_empty_item(trans, root, path, &key, 0);
|
|
if (ret)
|
|
goto out;
|
|
new_extents++;
|
|
}
|
|
|
|
btrfs_release_path(path);
|
|
ret = update_free_space_extent_count(trans, block_group, path,
|
|
new_extents);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
EXPORT_FOR_TESTS
|
|
int __remove_from_free_space_tree(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path, u64 start, u64 size)
|
|
{
|
|
struct btrfs_free_space_info *info;
|
|
u32 flags;
|
|
int ret;
|
|
|
|
if (test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) {
|
|
ret = __add_block_group_free_space(trans, block_group, path);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
info = search_free_space_info(NULL, block_group, path, 0);
|
|
if (IS_ERR(info))
|
|
return PTR_ERR(info);
|
|
flags = btrfs_free_space_flags(path->nodes[0], info);
|
|
btrfs_release_path(path);
|
|
|
|
if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) {
|
|
return modify_free_space_bitmap(trans, block_group, path,
|
|
start, size, 1);
|
|
} else {
|
|
return remove_free_space_extent(trans, block_group, path,
|
|
start, size);
|
|
}
|
|
}
|
|
|
|
int remove_from_free_space_tree(struct btrfs_trans_handle *trans,
|
|
u64 start, u64 size)
|
|
{
|
|
struct btrfs_block_group *block_group;
|
|
struct btrfs_path *path;
|
|
int ret;
|
|
|
|
if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE))
|
|
return 0;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
block_group = btrfs_lookup_block_group(trans->fs_info, start);
|
|
if (!block_group) {
|
|
ASSERT(0);
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
mutex_lock(&block_group->free_space_lock);
|
|
ret = __remove_from_free_space_tree(trans, block_group, path, start,
|
|
size);
|
|
mutex_unlock(&block_group->free_space_lock);
|
|
|
|
btrfs_put_block_group(block_group);
|
|
out:
|
|
btrfs_free_path(path);
|
|
if (ret)
|
|
btrfs_abort_transaction(trans, ret);
|
|
return ret;
|
|
}
|
|
|
|
static int add_free_space_extent(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path,
|
|
u64 start, u64 size)
|
|
{
|
|
struct btrfs_root *root = btrfs_free_space_root(block_group);
|
|
struct btrfs_key key, new_key;
|
|
u64 found_start, found_end;
|
|
u64 end = start + size;
|
|
int new_extents = 1;
|
|
int ret;
|
|
|
|
/*
|
|
* We are adding a new extent of free space, but we need to merge
|
|
* extents. There are four cases here:
|
|
*
|
|
* 1. The new extent does not have any immediate neighbors to merge
|
|
* with: add the new key and increment the free space extent count. We
|
|
* may need to convert the block group to bitmaps as a result.
|
|
* 2. The new extent has an immediate neighbor before it: remove the
|
|
* previous key and insert a new key combining both of them. There is no
|
|
* net change in the number of extents.
|
|
* 3. The new extent has an immediate neighbor after it: remove the next
|
|
* key and insert a new key combining both of them. There is no net
|
|
* change in the number of extents.
|
|
* 4. The new extent has immediate neighbors on both sides: remove both
|
|
* of the keys and insert a new key combining all of them. Where we used
|
|
* to have two extents, we now have one, so decrement the extent count.
|
|
*/
|
|
|
|
new_key.objectid = start;
|
|
new_key.type = BTRFS_FREE_SPACE_EXTENT_KEY;
|
|
new_key.offset = size;
|
|
|
|
/* Search for a neighbor on the left. */
|
|
if (start == block_group->start)
|
|
goto right;
|
|
key.objectid = start - 1;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1);
|
|
if (ret)
|
|
goto out;
|
|
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
|
|
if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) {
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY);
|
|
btrfs_release_path(path);
|
|
goto right;
|
|
}
|
|
|
|
found_start = key.objectid;
|
|
found_end = key.objectid + key.offset;
|
|
ASSERT(found_start >= block_group->start &&
|
|
found_end > block_group->start);
|
|
ASSERT(found_start < start && found_end <= start);
|
|
|
|
/*
|
|
* Delete the neighbor on the left and absorb it into the new key (cases
|
|
* 2 and 4).
|
|
*/
|
|
if (found_end == start) {
|
|
ret = btrfs_del_item(trans, root, path);
|
|
if (ret)
|
|
goto out;
|
|
new_key.objectid = found_start;
|
|
new_key.offset += key.offset;
|
|
new_extents--;
|
|
}
|
|
btrfs_release_path(path);
|
|
|
|
right:
|
|
/* Search for a neighbor on the right. */
|
|
if (end == block_group->start + block_group->length)
|
|
goto insert;
|
|
key.objectid = end;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1);
|
|
if (ret)
|
|
goto out;
|
|
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
|
|
if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) {
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY);
|
|
btrfs_release_path(path);
|
|
goto insert;
|
|
}
|
|
|
|
found_start = key.objectid;
|
|
found_end = key.objectid + key.offset;
|
|
ASSERT(found_start >= block_group->start &&
|
|
found_end > block_group->start);
|
|
ASSERT((found_start < start && found_end <= start) ||
|
|
(found_start >= end && found_end > end));
|
|
|
|
/*
|
|
* Delete the neighbor on the right and absorb it into the new key
|
|
* (cases 3 and 4).
|
|
*/
|
|
if (found_start == end) {
|
|
ret = btrfs_del_item(trans, root, path);
|
|
if (ret)
|
|
goto out;
|
|
new_key.offset += key.offset;
|
|
new_extents--;
|
|
}
|
|
btrfs_release_path(path);
|
|
|
|
insert:
|
|
/* Insert the new key (cases 1-4). */
|
|
ret = btrfs_insert_empty_item(trans, root, path, &new_key, 0);
|
|
if (ret)
|
|
goto out;
|
|
|
|
btrfs_release_path(path);
|
|
ret = update_free_space_extent_count(trans, block_group, path,
|
|
new_extents);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
EXPORT_FOR_TESTS
|
|
int __add_to_free_space_tree(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path, u64 start, u64 size)
|
|
{
|
|
struct btrfs_free_space_info *info;
|
|
u32 flags;
|
|
int ret;
|
|
|
|
if (test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) {
|
|
ret = __add_block_group_free_space(trans, block_group, path);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
info = search_free_space_info(NULL, block_group, path, 0);
|
|
if (IS_ERR(info))
|
|
return PTR_ERR(info);
|
|
flags = btrfs_free_space_flags(path->nodes[0], info);
|
|
btrfs_release_path(path);
|
|
|
|
if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) {
|
|
return modify_free_space_bitmap(trans, block_group, path,
|
|
start, size, 0);
|
|
} else {
|
|
return add_free_space_extent(trans, block_group, path, start,
|
|
size);
|
|
}
|
|
}
|
|
|
|
int add_to_free_space_tree(struct btrfs_trans_handle *trans,
|
|
u64 start, u64 size)
|
|
{
|
|
struct btrfs_block_group *block_group;
|
|
struct btrfs_path *path;
|
|
int ret;
|
|
|
|
if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE))
|
|
return 0;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
block_group = btrfs_lookup_block_group(trans->fs_info, start);
|
|
if (!block_group) {
|
|
ASSERT(0);
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
mutex_lock(&block_group->free_space_lock);
|
|
ret = __add_to_free_space_tree(trans, block_group, path, start, size);
|
|
mutex_unlock(&block_group->free_space_lock);
|
|
|
|
btrfs_put_block_group(block_group);
|
|
out:
|
|
btrfs_free_path(path);
|
|
if (ret)
|
|
btrfs_abort_transaction(trans, ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Populate the free space tree by walking the extent tree. Operations on the
|
|
* extent tree that happen as a result of writes to the free space tree will go
|
|
* through the normal add/remove hooks.
|
|
*/
|
|
static int populate_free_space_tree(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group)
|
|
{
|
|
struct btrfs_root *extent_root;
|
|
struct btrfs_path *path, *path2;
|
|
struct btrfs_key key;
|
|
u64 start, end;
|
|
int ret;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
path->reada = READA_FORWARD;
|
|
|
|
path2 = btrfs_alloc_path();
|
|
if (!path2) {
|
|
btrfs_free_path(path);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
ret = add_new_free_space_info(trans, block_group, path2);
|
|
if (ret)
|
|
goto out;
|
|
|
|
mutex_lock(&block_group->free_space_lock);
|
|
|
|
/*
|
|
* Iterate through all of the extent and metadata items in this block
|
|
* group, adding the free space between them and the free space at the
|
|
* end. Note that EXTENT_ITEM and METADATA_ITEM are less than
|
|
* BLOCK_GROUP_ITEM, so an extent may precede the block group that it's
|
|
* contained in.
|
|
*/
|
|
key.objectid = block_group->start;
|
|
key.type = BTRFS_EXTENT_ITEM_KEY;
|
|
key.offset = 0;
|
|
|
|
extent_root = btrfs_extent_root(trans->fs_info, key.objectid);
|
|
ret = btrfs_search_slot_for_read(extent_root, &key, path, 1, 0);
|
|
if (ret < 0)
|
|
goto out_locked;
|
|
ASSERT(ret == 0);
|
|
|
|
start = block_group->start;
|
|
end = block_group->start + block_group->length;
|
|
while (1) {
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
|
|
if (key.type == BTRFS_EXTENT_ITEM_KEY ||
|
|
key.type == BTRFS_METADATA_ITEM_KEY) {
|
|
if (key.objectid >= end)
|
|
break;
|
|
|
|
if (start < key.objectid) {
|
|
ret = __add_to_free_space_tree(trans,
|
|
block_group,
|
|
path2, start,
|
|
key.objectid -
|
|
start);
|
|
if (ret)
|
|
goto out_locked;
|
|
}
|
|
start = key.objectid;
|
|
if (key.type == BTRFS_METADATA_ITEM_KEY)
|
|
start += trans->fs_info->nodesize;
|
|
else
|
|
start += key.offset;
|
|
} else if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
|
|
if (key.objectid != block_group->start)
|
|
break;
|
|
}
|
|
|
|
ret = btrfs_next_item(extent_root, path);
|
|
if (ret < 0)
|
|
goto out_locked;
|
|
if (ret)
|
|
break;
|
|
}
|
|
if (start < end) {
|
|
ret = __add_to_free_space_tree(trans, block_group, path2,
|
|
start, end - start);
|
|
if (ret)
|
|
goto out_locked;
|
|
}
|
|
|
|
ret = 0;
|
|
out_locked:
|
|
mutex_unlock(&block_group->free_space_lock);
|
|
out:
|
|
btrfs_free_path(path2);
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_root *tree_root = fs_info->tree_root;
|
|
struct btrfs_root *free_space_root;
|
|
struct btrfs_block_group *block_group;
|
|
struct rb_node *node;
|
|
int ret;
|
|
|
|
trans = btrfs_start_transaction(tree_root, 0);
|
|
if (IS_ERR(trans))
|
|
return PTR_ERR(trans);
|
|
|
|
set_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
|
|
set_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags);
|
|
free_space_root = btrfs_create_tree(trans,
|
|
BTRFS_FREE_SPACE_TREE_OBJECTID);
|
|
if (IS_ERR(free_space_root)) {
|
|
ret = PTR_ERR(free_space_root);
|
|
goto abort;
|
|
}
|
|
ret = btrfs_global_root_insert(free_space_root);
|
|
if (ret) {
|
|
btrfs_put_root(free_space_root);
|
|
goto abort;
|
|
}
|
|
|
|
node = rb_first_cached(&fs_info->block_group_cache_tree);
|
|
while (node) {
|
|
block_group = rb_entry(node, struct btrfs_block_group,
|
|
cache_node);
|
|
ret = populate_free_space_tree(trans, block_group);
|
|
if (ret)
|
|
goto abort;
|
|
node = rb_next(node);
|
|
}
|
|
|
|
btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE);
|
|
btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID);
|
|
clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
|
|
ret = btrfs_commit_transaction(trans);
|
|
|
|
/*
|
|
* Now that we've committed the transaction any reading of our commit
|
|
* root will be safe, so we can cache from the free space tree now.
|
|
*/
|
|
clear_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags);
|
|
return ret;
|
|
|
|
abort:
|
|
clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
|
|
clear_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags);
|
|
btrfs_abort_transaction(trans, ret);
|
|
btrfs_end_transaction(trans);
|
|
return ret;
|
|
}
|
|
|
|
static int clear_free_space_tree(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root)
|
|
{
|
|
struct btrfs_path *path;
|
|
struct btrfs_key key;
|
|
int nr;
|
|
int ret;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
|
|
key.objectid = 0;
|
|
key.type = 0;
|
|
key.offset = 0;
|
|
|
|
while (1) {
|
|
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
|
|
if (ret < 0)
|
|
goto out;
|
|
|
|
nr = btrfs_header_nritems(path->nodes[0]);
|
|
if (!nr)
|
|
break;
|
|
|
|
path->slots[0] = 0;
|
|
ret = btrfs_del_items(trans, root, path, 0, nr);
|
|
if (ret)
|
|
goto out;
|
|
|
|
btrfs_release_path(path);
|
|
}
|
|
|
|
ret = 0;
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_delete_free_space_tree(struct btrfs_fs_info *fs_info)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_root *tree_root = fs_info->tree_root;
|
|
struct btrfs_key key = {
|
|
.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID,
|
|
.type = BTRFS_ROOT_ITEM_KEY,
|
|
.offset = 0,
|
|
};
|
|
struct btrfs_root *free_space_root = btrfs_global_root(fs_info, &key);
|
|
int ret;
|
|
|
|
trans = btrfs_start_transaction(tree_root, 0);
|
|
if (IS_ERR(trans))
|
|
return PTR_ERR(trans);
|
|
|
|
btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE);
|
|
btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID);
|
|
|
|
ret = clear_free_space_tree(trans, free_space_root);
|
|
if (ret)
|
|
goto abort;
|
|
|
|
ret = btrfs_del_root(trans, &free_space_root->root_key);
|
|
if (ret)
|
|
goto abort;
|
|
|
|
btrfs_global_root_delete(free_space_root);
|
|
|
|
spin_lock(&fs_info->trans_lock);
|
|
list_del(&free_space_root->dirty_list);
|
|
spin_unlock(&fs_info->trans_lock);
|
|
|
|
btrfs_tree_lock(free_space_root->node);
|
|
btrfs_clear_buffer_dirty(trans, free_space_root->node);
|
|
btrfs_tree_unlock(free_space_root->node);
|
|
btrfs_free_tree_block(trans, btrfs_root_id(free_space_root),
|
|
free_space_root->node, 0, 1);
|
|
|
|
btrfs_put_root(free_space_root);
|
|
|
|
return btrfs_commit_transaction(trans);
|
|
|
|
abort:
|
|
btrfs_abort_transaction(trans, ret);
|
|
btrfs_end_transaction(trans);
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_rebuild_free_space_tree(struct btrfs_fs_info *fs_info)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_key key = {
|
|
.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID,
|
|
.type = BTRFS_ROOT_ITEM_KEY,
|
|
.offset = 0,
|
|
};
|
|
struct btrfs_root *free_space_root = btrfs_global_root(fs_info, &key);
|
|
struct rb_node *node;
|
|
int ret;
|
|
|
|
trans = btrfs_start_transaction(free_space_root, 1);
|
|
if (IS_ERR(trans))
|
|
return PTR_ERR(trans);
|
|
|
|
set_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
|
|
set_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags);
|
|
|
|
ret = clear_free_space_tree(trans, free_space_root);
|
|
if (ret)
|
|
goto abort;
|
|
|
|
node = rb_first_cached(&fs_info->block_group_cache_tree);
|
|
while (node) {
|
|
struct btrfs_block_group *block_group;
|
|
|
|
block_group = rb_entry(node, struct btrfs_block_group,
|
|
cache_node);
|
|
ret = populate_free_space_tree(trans, block_group);
|
|
if (ret)
|
|
goto abort;
|
|
node = rb_next(node);
|
|
}
|
|
|
|
btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE);
|
|
btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID);
|
|
clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags);
|
|
|
|
ret = btrfs_commit_transaction(trans);
|
|
clear_bit(BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED, &fs_info->flags);
|
|
return ret;
|
|
abort:
|
|
btrfs_abort_transaction(trans, ret);
|
|
btrfs_end_transaction(trans);
|
|
return ret;
|
|
}
|
|
|
|
static int __add_block_group_free_space(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group,
|
|
struct btrfs_path *path)
|
|
{
|
|
int ret;
|
|
|
|
clear_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags);
|
|
|
|
ret = add_new_free_space_info(trans, block_group, path);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return __add_to_free_space_tree(trans, block_group, path,
|
|
block_group->start,
|
|
block_group->length);
|
|
}
|
|
|
|
int add_block_group_free_space(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group)
|
|
{
|
|
struct btrfs_fs_info *fs_info = trans->fs_info;
|
|
struct btrfs_path *path = NULL;
|
|
int ret = 0;
|
|
|
|
if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE))
|
|
return 0;
|
|
|
|
mutex_lock(&block_group->free_space_lock);
|
|
if (!test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags))
|
|
goto out;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
ret = __add_block_group_free_space(trans, block_group, path);
|
|
|
|
out:
|
|
btrfs_free_path(path);
|
|
mutex_unlock(&block_group->free_space_lock);
|
|
if (ret)
|
|
btrfs_abort_transaction(trans, ret);
|
|
return ret;
|
|
}
|
|
|
|
int remove_block_group_free_space(struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group *block_group)
|
|
{
|
|
struct btrfs_root *root = btrfs_free_space_root(block_group);
|
|
struct btrfs_path *path;
|
|
struct btrfs_key key, found_key;
|
|
struct extent_buffer *leaf;
|
|
u64 start, end;
|
|
int done = 0, nr;
|
|
int ret;
|
|
|
|
if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE))
|
|
return 0;
|
|
|
|
if (test_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &block_group->runtime_flags)) {
|
|
/* We never added this block group to the free space tree. */
|
|
return 0;
|
|
}
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
start = block_group->start;
|
|
end = block_group->start + block_group->length;
|
|
|
|
key.objectid = end - 1;
|
|
key.type = (u8)-1;
|
|
key.offset = (u64)-1;
|
|
|
|
while (!done) {
|
|
ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1);
|
|
if (ret)
|
|
goto out;
|
|
|
|
leaf = path->nodes[0];
|
|
nr = 0;
|
|
path->slots[0]++;
|
|
while (path->slots[0] > 0) {
|
|
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1);
|
|
|
|
if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) {
|
|
ASSERT(found_key.objectid == block_group->start);
|
|
ASSERT(found_key.offset == block_group->length);
|
|
done = 1;
|
|
nr++;
|
|
path->slots[0]--;
|
|
break;
|
|
} else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY ||
|
|
found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) {
|
|
ASSERT(found_key.objectid >= start);
|
|
ASSERT(found_key.objectid < end);
|
|
ASSERT(found_key.objectid + found_key.offset <= end);
|
|
nr++;
|
|
path->slots[0]--;
|
|
} else {
|
|
ASSERT(0);
|
|
}
|
|
}
|
|
|
|
ret = btrfs_del_items(trans, root, path, path->slots[0], nr);
|
|
if (ret)
|
|
goto out;
|
|
btrfs_release_path(path);
|
|
}
|
|
|
|
ret = 0;
|
|
out:
|
|
btrfs_free_path(path);
|
|
if (ret)
|
|
btrfs_abort_transaction(trans, ret);
|
|
return ret;
|
|
}
|
|
|
|
static int load_free_space_bitmaps(struct btrfs_caching_control *caching_ctl,
|
|
struct btrfs_path *path,
|
|
u32 expected_extent_count)
|
|
{
|
|
struct btrfs_block_group *block_group;
|
|
struct btrfs_fs_info *fs_info;
|
|
struct btrfs_root *root;
|
|
struct btrfs_key key;
|
|
int prev_bit = 0, bit;
|
|
/* Initialize to silence GCC. */
|
|
u64 extent_start = 0;
|
|
u64 end, offset;
|
|
u64 total_found = 0;
|
|
u32 extent_count = 0;
|
|
int ret;
|
|
|
|
block_group = caching_ctl->block_group;
|
|
fs_info = block_group->fs_info;
|
|
root = btrfs_free_space_root(block_group);
|
|
|
|
end = block_group->start + block_group->length;
|
|
|
|
while (1) {
|
|
ret = btrfs_next_item(root, path);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret)
|
|
break;
|
|
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
|
|
if (key.type == BTRFS_FREE_SPACE_INFO_KEY)
|
|
break;
|
|
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY);
|
|
ASSERT(key.objectid < end && key.objectid + key.offset <= end);
|
|
|
|
offset = key.objectid;
|
|
while (offset < key.objectid + key.offset) {
|
|
bit = free_space_test_bit(block_group, path, offset);
|
|
if (prev_bit == 0 && bit == 1) {
|
|
extent_start = offset;
|
|
} else if (prev_bit == 1 && bit == 0) {
|
|
u64 space_added;
|
|
|
|
ret = btrfs_add_new_free_space(block_group,
|
|
extent_start,
|
|
offset,
|
|
&space_added);
|
|
if (ret)
|
|
goto out;
|
|
total_found += space_added;
|
|
if (total_found > CACHING_CTL_WAKE_UP) {
|
|
total_found = 0;
|
|
wake_up(&caching_ctl->wait);
|
|
}
|
|
extent_count++;
|
|
}
|
|
prev_bit = bit;
|
|
offset += fs_info->sectorsize;
|
|
}
|
|
}
|
|
if (prev_bit == 1) {
|
|
ret = btrfs_add_new_free_space(block_group, extent_start, end, NULL);
|
|
if (ret)
|
|
goto out;
|
|
extent_count++;
|
|
}
|
|
|
|
if (extent_count != expected_extent_count) {
|
|
btrfs_err(fs_info,
|
|
"incorrect extent count for %llu; counted %u, expected %u",
|
|
block_group->start, extent_count,
|
|
expected_extent_count);
|
|
ASSERT(0);
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static int load_free_space_extents(struct btrfs_caching_control *caching_ctl,
|
|
struct btrfs_path *path,
|
|
u32 expected_extent_count)
|
|
{
|
|
struct btrfs_block_group *block_group;
|
|
struct btrfs_fs_info *fs_info;
|
|
struct btrfs_root *root;
|
|
struct btrfs_key key;
|
|
u64 end;
|
|
u64 total_found = 0;
|
|
u32 extent_count = 0;
|
|
int ret;
|
|
|
|
block_group = caching_ctl->block_group;
|
|
fs_info = block_group->fs_info;
|
|
root = btrfs_free_space_root(block_group);
|
|
|
|
end = block_group->start + block_group->length;
|
|
|
|
while (1) {
|
|
u64 space_added;
|
|
|
|
ret = btrfs_next_item(root, path);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret)
|
|
break;
|
|
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
|
|
|
|
if (key.type == BTRFS_FREE_SPACE_INFO_KEY)
|
|
break;
|
|
|
|
ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY);
|
|
ASSERT(key.objectid < end && key.objectid + key.offset <= end);
|
|
|
|
ret = btrfs_add_new_free_space(block_group, key.objectid,
|
|
key.objectid + key.offset,
|
|
&space_added);
|
|
if (ret)
|
|
goto out;
|
|
total_found += space_added;
|
|
if (total_found > CACHING_CTL_WAKE_UP) {
|
|
total_found = 0;
|
|
wake_up(&caching_ctl->wait);
|
|
}
|
|
extent_count++;
|
|
}
|
|
|
|
if (extent_count != expected_extent_count) {
|
|
btrfs_err(fs_info,
|
|
"incorrect extent count for %llu; counted %u, expected %u",
|
|
block_group->start, extent_count,
|
|
expected_extent_count);
|
|
ASSERT(0);
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
int load_free_space_tree(struct btrfs_caching_control *caching_ctl)
|
|
{
|
|
struct btrfs_block_group *block_group;
|
|
struct btrfs_free_space_info *info;
|
|
struct btrfs_path *path;
|
|
u32 extent_count, flags;
|
|
int ret;
|
|
|
|
block_group = caching_ctl->block_group;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
|
|
/*
|
|
* Just like caching_thread() doesn't want to deadlock on the extent
|
|
* tree, we don't want to deadlock on the free space tree.
|
|
*/
|
|
path->skip_locking = 1;
|
|
path->search_commit_root = 1;
|
|
path->reada = READA_FORWARD;
|
|
|
|
info = search_free_space_info(NULL, block_group, path, 0);
|
|
if (IS_ERR(info)) {
|
|
ret = PTR_ERR(info);
|
|
goto out;
|
|
}
|
|
extent_count = btrfs_free_space_extent_count(path->nodes[0], info);
|
|
flags = btrfs_free_space_flags(path->nodes[0], info);
|
|
|
|
/*
|
|
* We left path pointing to the free space info item, so now
|
|
* load_free_space_foo can just iterate through the free space tree from
|
|
* there.
|
|
*/
|
|
if (flags & BTRFS_FREE_SPACE_USING_BITMAPS)
|
|
ret = load_free_space_bitmaps(caching_ctl, path, extent_count);
|
|
else
|
|
ret = load_free_space_extents(caching_ctl, path, extent_count);
|
|
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|