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![Josef Bacik](/assets/img/avatar_default.png)
If our space cache is wrong, we do the right thing and free up everything that we loaded, however we don't reset the total_bitmaps counter or the thresholds or anything. So in btrfs_remove_free_space_cache make sure to call free_bitmap() if it's a bitmap, this will keep us from panicing when we check to make sure we don't have too many bitmaps. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2344 lines
58 KiB
C
2344 lines
58 KiB
C
/*
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* Copyright (C) 2008 Red Hat. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <linux/pagemap.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/math64.h>
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#include "ctree.h"
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#include "free-space-cache.h"
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#include "transaction.h"
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#include "disk-io.h"
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#include "extent_io.h"
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#define BITS_PER_BITMAP (PAGE_CACHE_SIZE * 8)
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#define MAX_CACHE_BYTES_PER_GIG (32 * 1024)
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static void recalculate_thresholds(struct btrfs_block_group_cache
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*block_group);
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static int link_free_space(struct btrfs_block_group_cache *block_group,
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struct btrfs_free_space *info);
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struct inode *lookup_free_space_inode(struct btrfs_root *root,
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struct btrfs_block_group_cache
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*block_group, struct btrfs_path *path)
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{
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struct btrfs_key key;
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struct btrfs_key location;
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struct btrfs_disk_key disk_key;
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struct btrfs_free_space_header *header;
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struct extent_buffer *leaf;
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struct inode *inode = NULL;
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int ret;
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spin_lock(&block_group->lock);
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if (block_group->inode)
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inode = igrab(block_group->inode);
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spin_unlock(&block_group->lock);
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if (inode)
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return inode;
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key.objectid = BTRFS_FREE_SPACE_OBJECTID;
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key.offset = block_group->key.objectid;
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key.type = 0;
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ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
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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_release_path(root, path);
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return ERR_PTR(-ENOENT);
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}
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leaf = path->nodes[0];
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header = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_free_space_header);
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btrfs_free_space_key(leaf, header, &disk_key);
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btrfs_disk_key_to_cpu(&location, &disk_key);
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btrfs_release_path(root, path);
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inode = btrfs_iget(root->fs_info->sb, &location, root, NULL);
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if (!inode)
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return ERR_PTR(-ENOENT);
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if (IS_ERR(inode))
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return inode;
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if (is_bad_inode(inode)) {
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iput(inode);
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return ERR_PTR(-ENOENT);
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}
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inode->i_mapping->flags &= ~__GFP_FS;
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spin_lock(&block_group->lock);
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if (!root->fs_info->closing) {
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block_group->inode = igrab(inode);
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block_group->iref = 1;
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}
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spin_unlock(&block_group->lock);
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return inode;
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}
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int create_free_space_inode(struct btrfs_root *root,
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struct btrfs_trans_handle *trans,
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struct btrfs_block_group_cache *block_group,
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struct btrfs_path *path)
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{
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struct btrfs_key key;
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struct btrfs_disk_key disk_key;
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struct btrfs_free_space_header *header;
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struct btrfs_inode_item *inode_item;
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struct extent_buffer *leaf;
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u64 objectid;
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int ret;
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ret = btrfs_find_free_objectid(trans, root, 0, &objectid);
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if (ret < 0)
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return ret;
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ret = btrfs_insert_empty_inode(trans, root, path, objectid);
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if (ret)
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return ret;
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leaf = path->nodes[0];
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inode_item = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_inode_item);
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btrfs_item_key(leaf, &disk_key, path->slots[0]);
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memset_extent_buffer(leaf, 0, (unsigned long)inode_item,
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sizeof(*inode_item));
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btrfs_set_inode_generation(leaf, inode_item, trans->transid);
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btrfs_set_inode_size(leaf, inode_item, 0);
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btrfs_set_inode_nbytes(leaf, inode_item, 0);
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btrfs_set_inode_uid(leaf, inode_item, 0);
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btrfs_set_inode_gid(leaf, inode_item, 0);
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btrfs_set_inode_mode(leaf, inode_item, S_IFREG | 0600);
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btrfs_set_inode_flags(leaf, inode_item, BTRFS_INODE_NOCOMPRESS |
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BTRFS_INODE_PREALLOC | BTRFS_INODE_NODATASUM);
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btrfs_set_inode_nlink(leaf, inode_item, 1);
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btrfs_set_inode_transid(leaf, inode_item, trans->transid);
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btrfs_set_inode_block_group(leaf, inode_item,
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block_group->key.objectid);
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btrfs_mark_buffer_dirty(leaf);
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btrfs_release_path(root, path);
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key.objectid = BTRFS_FREE_SPACE_OBJECTID;
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key.offset = block_group->key.objectid;
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key.type = 0;
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ret = btrfs_insert_empty_item(trans, root, path, &key,
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sizeof(struct btrfs_free_space_header));
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if (ret < 0) {
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btrfs_release_path(root, path);
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return ret;
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}
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leaf = path->nodes[0];
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header = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_free_space_header);
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memset_extent_buffer(leaf, 0, (unsigned long)header, sizeof(*header));
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btrfs_set_free_space_key(leaf, header, &disk_key);
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btrfs_mark_buffer_dirty(leaf);
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btrfs_release_path(root, path);
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return 0;
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}
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int btrfs_truncate_free_space_cache(struct btrfs_root *root,
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struct btrfs_trans_handle *trans,
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struct btrfs_path *path,
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struct inode *inode)
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{
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loff_t oldsize;
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int ret = 0;
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trans->block_rsv = root->orphan_block_rsv;
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ret = btrfs_block_rsv_check(trans, root,
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root->orphan_block_rsv,
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0, 5);
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if (ret)
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return ret;
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oldsize = i_size_read(inode);
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btrfs_i_size_write(inode, 0);
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truncate_pagecache(inode, oldsize, 0);
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/*
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* We don't need an orphan item because truncating the free space cache
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* will never be split across transactions.
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*/
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ret = btrfs_truncate_inode_items(trans, root, inode,
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0, BTRFS_EXTENT_DATA_KEY);
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if (ret) {
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WARN_ON(1);
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return ret;
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}
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return btrfs_update_inode(trans, root, inode);
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}
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static int readahead_cache(struct inode *inode)
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{
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struct file_ra_state *ra;
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unsigned long last_index;
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ra = kzalloc(sizeof(*ra), GFP_NOFS);
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if (!ra)
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return -ENOMEM;
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file_ra_state_init(ra, inode->i_mapping);
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last_index = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
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page_cache_sync_readahead(inode->i_mapping, ra, NULL, 0, last_index);
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kfree(ra);
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return 0;
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}
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int load_free_space_cache(struct btrfs_fs_info *fs_info,
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struct btrfs_block_group_cache *block_group)
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{
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struct btrfs_root *root = fs_info->tree_root;
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struct inode *inode;
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struct btrfs_free_space_header *header;
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struct extent_buffer *leaf;
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struct page *page;
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struct btrfs_path *path;
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u32 *checksums = NULL, *crc;
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char *disk_crcs = NULL;
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struct btrfs_key key;
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struct list_head bitmaps;
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u64 num_entries;
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u64 num_bitmaps;
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u64 generation;
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u64 used = btrfs_block_group_used(&block_group->item);
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u32 cur_crc = ~(u32)0;
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pgoff_t index = 0;
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unsigned long first_page_offset;
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int num_checksums;
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int ret = 0;
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/*
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* If we're unmounting then just return, since this does a search on the
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* normal root and not the commit root and we could deadlock.
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*/
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smp_mb();
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if (fs_info->closing)
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return 0;
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/*
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* If this block group has been marked to be cleared for one reason or
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* another then we can't trust the on disk cache, so just return.
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*/
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spin_lock(&block_group->lock);
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if (block_group->disk_cache_state != BTRFS_DC_WRITTEN) {
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spin_unlock(&block_group->lock);
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return 0;
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}
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spin_unlock(&block_group->lock);
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INIT_LIST_HEAD(&bitmaps);
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path = btrfs_alloc_path();
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if (!path)
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return 0;
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inode = lookup_free_space_inode(root, block_group, path);
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if (IS_ERR(inode)) {
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btrfs_free_path(path);
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return 0;
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}
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/* Nothing in the space cache, goodbye */
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if (!i_size_read(inode)) {
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btrfs_free_path(path);
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goto out;
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}
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key.objectid = BTRFS_FREE_SPACE_OBJECTID;
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key.offset = block_group->key.objectid;
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key.type = 0;
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ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
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if (ret) {
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btrfs_free_path(path);
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goto out;
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}
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leaf = path->nodes[0];
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header = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_free_space_header);
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num_entries = btrfs_free_space_entries(leaf, header);
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num_bitmaps = btrfs_free_space_bitmaps(leaf, header);
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generation = btrfs_free_space_generation(leaf, header);
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btrfs_free_path(path);
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if (BTRFS_I(inode)->generation != generation) {
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printk(KERN_ERR "btrfs: free space inode generation (%llu) did"
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" not match free space cache generation (%llu) for "
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"block group %llu\n",
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(unsigned long long)BTRFS_I(inode)->generation,
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(unsigned long long)generation,
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(unsigned long long)block_group->key.objectid);
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goto free_cache;
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}
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if (!num_entries)
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goto out;
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/* Setup everything for doing checksumming */
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num_checksums = i_size_read(inode) / PAGE_CACHE_SIZE;
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checksums = crc = kzalloc(sizeof(u32) * num_checksums, GFP_NOFS);
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if (!checksums)
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goto out;
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first_page_offset = (sizeof(u32) * num_checksums) + sizeof(u64);
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disk_crcs = kzalloc(first_page_offset, GFP_NOFS);
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if (!disk_crcs)
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goto out;
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ret = readahead_cache(inode);
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if (ret) {
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ret = 0;
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goto out;
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}
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while (1) {
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struct btrfs_free_space_entry *entry;
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struct btrfs_free_space *e;
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void *addr;
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unsigned long offset = 0;
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unsigned long start_offset = 0;
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int need_loop = 0;
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if (!num_entries && !num_bitmaps)
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break;
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if (index == 0) {
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start_offset = first_page_offset;
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offset = start_offset;
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}
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page = grab_cache_page(inode->i_mapping, index);
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if (!page) {
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ret = 0;
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goto free_cache;
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}
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if (!PageUptodate(page)) {
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btrfs_readpage(NULL, page);
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lock_page(page);
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if (!PageUptodate(page)) {
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unlock_page(page);
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page_cache_release(page);
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printk(KERN_ERR "btrfs: error reading free "
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"space cache: %llu\n",
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(unsigned long long)
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block_group->key.objectid);
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goto free_cache;
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}
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}
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addr = kmap(page);
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if (index == 0) {
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u64 *gen;
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memcpy(disk_crcs, addr, first_page_offset);
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gen = addr + (sizeof(u32) * num_checksums);
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if (*gen != BTRFS_I(inode)->generation) {
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printk(KERN_ERR "btrfs: space cache generation"
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" (%llu) does not match inode (%llu) "
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"for block group %llu\n",
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(unsigned long long)*gen,
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(unsigned long long)
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BTRFS_I(inode)->generation,
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(unsigned long long)
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block_group->key.objectid);
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kunmap(page);
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unlock_page(page);
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page_cache_release(page);
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goto free_cache;
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}
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crc = (u32 *)disk_crcs;
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}
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entry = addr + start_offset;
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|
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/* First lets check our crc before we do anything fun */
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cur_crc = ~(u32)0;
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cur_crc = btrfs_csum_data(root, addr + start_offset, cur_crc,
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PAGE_CACHE_SIZE - start_offset);
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btrfs_csum_final(cur_crc, (char *)&cur_crc);
|
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if (cur_crc != *crc) {
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printk(KERN_ERR "btrfs: crc mismatch for page %lu in "
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"block group %llu\n", index,
|
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(unsigned long long)block_group->key.objectid);
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kunmap(page);
|
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unlock_page(page);
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page_cache_release(page);
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goto free_cache;
|
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}
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crc++;
|
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|
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while (1) {
|
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if (!num_entries)
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break;
|
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|
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need_loop = 1;
|
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e = kmem_cache_zalloc(btrfs_free_space_cachep,
|
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GFP_NOFS);
|
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if (!e) {
|
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kunmap(page);
|
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unlock_page(page);
|
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page_cache_release(page);
|
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goto free_cache;
|
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}
|
|
|
|
e->offset = le64_to_cpu(entry->offset);
|
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e->bytes = le64_to_cpu(entry->bytes);
|
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if (!e->bytes) {
|
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kunmap(page);
|
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kmem_cache_free(btrfs_free_space_cachep, e);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
goto free_cache;
|
|
}
|
|
|
|
if (entry->type == BTRFS_FREE_SPACE_EXTENT) {
|
|
spin_lock(&block_group->tree_lock);
|
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ret = link_free_space(block_group, e);
|
|
spin_unlock(&block_group->tree_lock);
|
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BUG_ON(ret);
|
|
} else {
|
|
e->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS);
|
|
if (!e->bitmap) {
|
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kunmap(page);
|
|
kmem_cache_free(
|
|
btrfs_free_space_cachep, e);
|
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unlock_page(page);
|
|
page_cache_release(page);
|
|
goto free_cache;
|
|
}
|
|
spin_lock(&block_group->tree_lock);
|
|
ret = link_free_space(block_group, e);
|
|
block_group->total_bitmaps++;
|
|
recalculate_thresholds(block_group);
|
|
spin_unlock(&block_group->tree_lock);
|
|
list_add_tail(&e->list, &bitmaps);
|
|
}
|
|
|
|
num_entries--;
|
|
offset += sizeof(struct btrfs_free_space_entry);
|
|
if (offset + sizeof(struct btrfs_free_space_entry) >=
|
|
PAGE_CACHE_SIZE)
|
|
break;
|
|
entry++;
|
|
}
|
|
|
|
/*
|
|
* We read an entry out of this page, we need to move on to the
|
|
* next page.
|
|
*/
|
|
if (need_loop) {
|
|
kunmap(page);
|
|
goto next;
|
|
}
|
|
|
|
/*
|
|
* We add the bitmaps at the end of the entries in order that
|
|
* the bitmap entries are added to the cache.
|
|
*/
|
|
e = list_entry(bitmaps.next, struct btrfs_free_space, list);
|
|
list_del_init(&e->list);
|
|
memcpy(e->bitmap, addr, PAGE_CACHE_SIZE);
|
|
kunmap(page);
|
|
num_bitmaps--;
|
|
next:
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
index++;
|
|
}
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
if (block_group->free_space != (block_group->key.offset - used -
|
|
block_group->bytes_super)) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
printk(KERN_ERR "block group %llu has an wrong amount of free "
|
|
"space\n", block_group->key.objectid);
|
|
ret = 0;
|
|
goto free_cache;
|
|
}
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
ret = 1;
|
|
out:
|
|
kfree(checksums);
|
|
kfree(disk_crcs);
|
|
iput(inode);
|
|
return ret;
|
|
|
|
free_cache:
|
|
/* This cache is bogus, make sure it gets cleared */
|
|
spin_lock(&block_group->lock);
|
|
block_group->disk_cache_state = BTRFS_DC_CLEAR;
|
|
spin_unlock(&block_group->lock);
|
|
btrfs_remove_free_space_cache(block_group);
|
|
goto out;
|
|
}
|
|
|
|
int btrfs_write_out_cache(struct btrfs_root *root,
|
|
struct btrfs_trans_handle *trans,
|
|
struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_path *path)
|
|
{
|
|
struct btrfs_free_space_header *header;
|
|
struct extent_buffer *leaf;
|
|
struct inode *inode;
|
|
struct rb_node *node;
|
|
struct list_head *pos, *n;
|
|
struct page **pages;
|
|
struct page *page;
|
|
struct extent_state *cached_state = NULL;
|
|
struct btrfs_free_cluster *cluster = NULL;
|
|
struct extent_io_tree *unpin = NULL;
|
|
struct list_head bitmap_list;
|
|
struct btrfs_key key;
|
|
u64 start, end, len;
|
|
u64 bytes = 0;
|
|
u32 *crc, *checksums;
|
|
unsigned long first_page_offset;
|
|
int index = 0, num_pages = 0;
|
|
int entries = 0;
|
|
int bitmaps = 0;
|
|
int ret = 0;
|
|
bool next_page = false;
|
|
bool out_of_space = false;
|
|
|
|
root = root->fs_info->tree_root;
|
|
|
|
INIT_LIST_HEAD(&bitmap_list);
|
|
|
|
spin_lock(&block_group->lock);
|
|
if (block_group->disk_cache_state < BTRFS_DC_SETUP) {
|
|
spin_unlock(&block_group->lock);
|
|
return 0;
|
|
}
|
|
spin_unlock(&block_group->lock);
|
|
|
|
inode = lookup_free_space_inode(root, block_group, path);
|
|
if (IS_ERR(inode))
|
|
return 0;
|
|
|
|
if (!i_size_read(inode)) {
|
|
iput(inode);
|
|
return 0;
|
|
}
|
|
|
|
node = rb_first(&block_group->free_space_offset);
|
|
if (!node) {
|
|
iput(inode);
|
|
return 0;
|
|
}
|
|
|
|
num_pages = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
|
|
PAGE_CACHE_SHIFT;
|
|
filemap_write_and_wait(inode->i_mapping);
|
|
btrfs_wait_ordered_range(inode, inode->i_size &
|
|
~(root->sectorsize - 1), (u64)-1);
|
|
|
|
/* We need a checksum per page. */
|
|
crc = checksums = kzalloc(sizeof(u32) * num_pages, GFP_NOFS);
|
|
if (!crc) {
|
|
iput(inode);
|
|
return 0;
|
|
}
|
|
|
|
pages = kzalloc(sizeof(struct page *) * num_pages, GFP_NOFS);
|
|
if (!pages) {
|
|
kfree(crc);
|
|
iput(inode);
|
|
return 0;
|
|
}
|
|
|
|
/* Since the first page has all of our checksums and our generation we
|
|
* need to calculate the offset into the page that we can start writing
|
|
* our entries.
|
|
*/
|
|
first_page_offset = (sizeof(u32) * num_pages) + sizeof(u64);
|
|
|
|
/* Get the cluster for this block_group if it exists */
|
|
if (!list_empty(&block_group->cluster_list))
|
|
cluster = list_entry(block_group->cluster_list.next,
|
|
struct btrfs_free_cluster,
|
|
block_group_list);
|
|
|
|
/*
|
|
* We shouldn't have switched the pinned extents yet so this is the
|
|
* right one
|
|
*/
|
|
unpin = root->fs_info->pinned_extents;
|
|
|
|
/*
|
|
* Lock all pages first so we can lock the extent safely.
|
|
*
|
|
* NOTE: Because we hold the ref the entire time we're going to write to
|
|
* the page find_get_page should never fail, so we don't do a check
|
|
* after find_get_page at this point. Just putting this here so people
|
|
* know and don't freak out.
|
|
*/
|
|
while (index < num_pages) {
|
|
page = grab_cache_page(inode->i_mapping, index);
|
|
if (!page) {
|
|
int i;
|
|
|
|
for (i = 0; i < num_pages; i++) {
|
|
unlock_page(pages[i]);
|
|
page_cache_release(pages[i]);
|
|
}
|
|
goto out_free;
|
|
}
|
|
pages[index] = page;
|
|
index++;
|
|
}
|
|
|
|
index = 0;
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1,
|
|
0, &cached_state, GFP_NOFS);
|
|
|
|
/*
|
|
* When searching for pinned extents, we need to start at our start
|
|
* offset.
|
|
*/
|
|
start = block_group->key.objectid;
|
|
|
|
/* Write out the extent entries */
|
|
do {
|
|
struct btrfs_free_space_entry *entry;
|
|
void *addr;
|
|
unsigned long offset = 0;
|
|
unsigned long start_offset = 0;
|
|
|
|
next_page = false;
|
|
|
|
if (index == 0) {
|
|
start_offset = first_page_offset;
|
|
offset = start_offset;
|
|
}
|
|
|
|
if (index >= num_pages) {
|
|
out_of_space = true;
|
|
break;
|
|
}
|
|
|
|
page = pages[index];
|
|
|
|
addr = kmap(page);
|
|
entry = addr + start_offset;
|
|
|
|
memset(addr, 0, PAGE_CACHE_SIZE);
|
|
while (node && !next_page) {
|
|
struct btrfs_free_space *e;
|
|
|
|
e = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
entries++;
|
|
|
|
entry->offset = cpu_to_le64(e->offset);
|
|
entry->bytes = cpu_to_le64(e->bytes);
|
|
if (e->bitmap) {
|
|
entry->type = BTRFS_FREE_SPACE_BITMAP;
|
|
list_add_tail(&e->list, &bitmap_list);
|
|
bitmaps++;
|
|
} else {
|
|
entry->type = BTRFS_FREE_SPACE_EXTENT;
|
|
}
|
|
node = rb_next(node);
|
|
if (!node && cluster) {
|
|
node = rb_first(&cluster->root);
|
|
cluster = NULL;
|
|
}
|
|
offset += sizeof(struct btrfs_free_space_entry);
|
|
if (offset + sizeof(struct btrfs_free_space_entry) >=
|
|
PAGE_CACHE_SIZE)
|
|
next_page = true;
|
|
entry++;
|
|
}
|
|
|
|
/*
|
|
* We want to add any pinned extents to our free space cache
|
|
* so we don't leak the space
|
|
*/
|
|
while (!next_page && (start < block_group->key.objectid +
|
|
block_group->key.offset)) {
|
|
ret = find_first_extent_bit(unpin, start, &start, &end,
|
|
EXTENT_DIRTY);
|
|
if (ret) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
|
|
/* This pinned extent is out of our range */
|
|
if (start >= block_group->key.objectid +
|
|
block_group->key.offset)
|
|
break;
|
|
|
|
len = block_group->key.objectid +
|
|
block_group->key.offset - start;
|
|
len = min(len, end + 1 - start);
|
|
|
|
entries++;
|
|
entry->offset = cpu_to_le64(start);
|
|
entry->bytes = cpu_to_le64(len);
|
|
entry->type = BTRFS_FREE_SPACE_EXTENT;
|
|
|
|
start = end + 1;
|
|
offset += sizeof(struct btrfs_free_space_entry);
|
|
if (offset + sizeof(struct btrfs_free_space_entry) >=
|
|
PAGE_CACHE_SIZE)
|
|
next_page = true;
|
|
entry++;
|
|
}
|
|
*crc = ~(u32)0;
|
|
*crc = btrfs_csum_data(root, addr + start_offset, *crc,
|
|
PAGE_CACHE_SIZE - start_offset);
|
|
kunmap(page);
|
|
|
|
btrfs_csum_final(*crc, (char *)crc);
|
|
crc++;
|
|
|
|
bytes += PAGE_CACHE_SIZE;
|
|
|
|
index++;
|
|
} while (node || next_page);
|
|
|
|
/* Write out the bitmaps */
|
|
list_for_each_safe(pos, n, &bitmap_list) {
|
|
void *addr;
|
|
struct btrfs_free_space *entry =
|
|
list_entry(pos, struct btrfs_free_space, list);
|
|
|
|
if (index >= num_pages) {
|
|
out_of_space = true;
|
|
break;
|
|
}
|
|
page = pages[index];
|
|
|
|
addr = kmap(page);
|
|
memcpy(addr, entry->bitmap, PAGE_CACHE_SIZE);
|
|
*crc = ~(u32)0;
|
|
*crc = btrfs_csum_data(root, addr, *crc, PAGE_CACHE_SIZE);
|
|
kunmap(page);
|
|
btrfs_csum_final(*crc, (char *)crc);
|
|
crc++;
|
|
bytes += PAGE_CACHE_SIZE;
|
|
|
|
list_del_init(&entry->list);
|
|
index++;
|
|
}
|
|
|
|
if (out_of_space) {
|
|
btrfs_drop_pages(pages, num_pages);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0,
|
|
i_size_read(inode) - 1, &cached_state,
|
|
GFP_NOFS);
|
|
ret = 0;
|
|
goto out_free;
|
|
}
|
|
|
|
/* Zero out the rest of the pages just to make sure */
|
|
while (index < num_pages) {
|
|
void *addr;
|
|
|
|
page = pages[index];
|
|
addr = kmap(page);
|
|
memset(addr, 0, PAGE_CACHE_SIZE);
|
|
kunmap(page);
|
|
bytes += PAGE_CACHE_SIZE;
|
|
index++;
|
|
}
|
|
|
|
/* Write the checksums and trans id to the first page */
|
|
{
|
|
void *addr;
|
|
u64 *gen;
|
|
|
|
page = pages[0];
|
|
|
|
addr = kmap(page);
|
|
memcpy(addr, checksums, sizeof(u32) * num_pages);
|
|
gen = addr + (sizeof(u32) * num_pages);
|
|
*gen = trans->transid;
|
|
kunmap(page);
|
|
}
|
|
|
|
ret = btrfs_dirty_pages(root, inode, pages, num_pages, 0,
|
|
bytes, &cached_state);
|
|
btrfs_drop_pages(pages, num_pages);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0,
|
|
i_size_read(inode) - 1, &cached_state, GFP_NOFS);
|
|
|
|
if (ret) {
|
|
ret = 0;
|
|
goto out_free;
|
|
}
|
|
|
|
BTRFS_I(inode)->generation = trans->transid;
|
|
|
|
filemap_write_and_wait(inode->i_mapping);
|
|
|
|
key.objectid = BTRFS_FREE_SPACE_OBJECTID;
|
|
key.offset = block_group->key.objectid;
|
|
key.type = 0;
|
|
|
|
ret = btrfs_search_slot(trans, root, &key, path, 1, 1);
|
|
if (ret < 0) {
|
|
ret = 0;
|
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1,
|
|
EXTENT_DIRTY | EXTENT_DELALLOC |
|
|
EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS);
|
|
goto out_free;
|
|
}
|
|
leaf = path->nodes[0];
|
|
if (ret > 0) {
|
|
struct btrfs_key found_key;
|
|
BUG_ON(!path->slots[0]);
|
|
path->slots[0]--;
|
|
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
|
|
if (found_key.objectid != BTRFS_FREE_SPACE_OBJECTID ||
|
|
found_key.offset != block_group->key.objectid) {
|
|
ret = 0;
|
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1,
|
|
EXTENT_DIRTY | EXTENT_DELALLOC |
|
|
EXTENT_DO_ACCOUNTING, 0, 0, NULL,
|
|
GFP_NOFS);
|
|
btrfs_release_path(root, path);
|
|
goto out_free;
|
|
}
|
|
}
|
|
header = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_free_space_header);
|
|
btrfs_set_free_space_entries(leaf, header, entries);
|
|
btrfs_set_free_space_bitmaps(leaf, header, bitmaps);
|
|
btrfs_set_free_space_generation(leaf, header, trans->transid);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
btrfs_release_path(root, path);
|
|
|
|
ret = 1;
|
|
|
|
out_free:
|
|
if (ret == 0) {
|
|
invalidate_inode_pages2_range(inode->i_mapping, 0, index);
|
|
spin_lock(&block_group->lock);
|
|
block_group->disk_cache_state = BTRFS_DC_ERROR;
|
|
spin_unlock(&block_group->lock);
|
|
BTRFS_I(inode)->generation = 0;
|
|
}
|
|
kfree(checksums);
|
|
kfree(pages);
|
|
btrfs_update_inode(trans, root, inode);
|
|
iput(inode);
|
|
return ret;
|
|
}
|
|
|
|
static inline unsigned long offset_to_bit(u64 bitmap_start, u64 sectorsize,
|
|
u64 offset)
|
|
{
|
|
BUG_ON(offset < bitmap_start);
|
|
offset -= bitmap_start;
|
|
return (unsigned long)(div64_u64(offset, sectorsize));
|
|
}
|
|
|
|
static inline unsigned long bytes_to_bits(u64 bytes, u64 sectorsize)
|
|
{
|
|
return (unsigned long)(div64_u64(bytes, sectorsize));
|
|
}
|
|
|
|
static inline u64 offset_to_bitmap(struct btrfs_block_group_cache *block_group,
|
|
u64 offset)
|
|
{
|
|
u64 bitmap_start;
|
|
u64 bytes_per_bitmap;
|
|
|
|
bytes_per_bitmap = BITS_PER_BITMAP * block_group->sectorsize;
|
|
bitmap_start = offset - block_group->key.objectid;
|
|
bitmap_start = div64_u64(bitmap_start, bytes_per_bitmap);
|
|
bitmap_start *= bytes_per_bitmap;
|
|
bitmap_start += block_group->key.objectid;
|
|
|
|
return bitmap_start;
|
|
}
|
|
|
|
static int tree_insert_offset(struct rb_root *root, u64 offset,
|
|
struct rb_node *node, int bitmap)
|
|
{
|
|
struct rb_node **p = &root->rb_node;
|
|
struct rb_node *parent = NULL;
|
|
struct btrfs_free_space *info;
|
|
|
|
while (*p) {
|
|
parent = *p;
|
|
info = rb_entry(parent, struct btrfs_free_space, offset_index);
|
|
|
|
if (offset < info->offset) {
|
|
p = &(*p)->rb_left;
|
|
} else if (offset > info->offset) {
|
|
p = &(*p)->rb_right;
|
|
} else {
|
|
/*
|
|
* we could have a bitmap entry and an extent entry
|
|
* share the same offset. If this is the case, we want
|
|
* the extent entry to always be found first if we do a
|
|
* linear search through the tree, since we want to have
|
|
* the quickest allocation time, and allocating from an
|
|
* extent is faster than allocating from a bitmap. So
|
|
* if we're inserting a bitmap and we find an entry at
|
|
* this offset, we want to go right, or after this entry
|
|
* logically. If we are inserting an extent and we've
|
|
* found a bitmap, we want to go left, or before
|
|
* logically.
|
|
*/
|
|
if (bitmap) {
|
|
WARN_ON(info->bitmap);
|
|
p = &(*p)->rb_right;
|
|
} else {
|
|
WARN_ON(!info->bitmap);
|
|
p = &(*p)->rb_left;
|
|
}
|
|
}
|
|
}
|
|
|
|
rb_link_node(node, parent, p);
|
|
rb_insert_color(node, root);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* searches the tree for the given offset.
|
|
*
|
|
* fuzzy - If this is set, then we are trying to make an allocation, and we just
|
|
* want a section that has at least bytes size and comes at or after the given
|
|
* offset.
|
|
*/
|
|
static struct btrfs_free_space *
|
|
tree_search_offset(struct btrfs_block_group_cache *block_group,
|
|
u64 offset, int bitmap_only, int fuzzy)
|
|
{
|
|
struct rb_node *n = block_group->free_space_offset.rb_node;
|
|
struct btrfs_free_space *entry, *prev = NULL;
|
|
|
|
/* find entry that is closest to the 'offset' */
|
|
while (1) {
|
|
if (!n) {
|
|
entry = NULL;
|
|
break;
|
|
}
|
|
|
|
entry = rb_entry(n, struct btrfs_free_space, offset_index);
|
|
prev = entry;
|
|
|
|
if (offset < entry->offset)
|
|
n = n->rb_left;
|
|
else if (offset > entry->offset)
|
|
n = n->rb_right;
|
|
else
|
|
break;
|
|
}
|
|
|
|
if (bitmap_only) {
|
|
if (!entry)
|
|
return NULL;
|
|
if (entry->bitmap)
|
|
return entry;
|
|
|
|
/*
|
|
* bitmap entry and extent entry may share same offset,
|
|
* in that case, bitmap entry comes after extent entry.
|
|
*/
|
|
n = rb_next(n);
|
|
if (!n)
|
|
return NULL;
|
|
entry = rb_entry(n, struct btrfs_free_space, offset_index);
|
|
if (entry->offset != offset)
|
|
return NULL;
|
|
|
|
WARN_ON(!entry->bitmap);
|
|
return entry;
|
|
} else if (entry) {
|
|
if (entry->bitmap) {
|
|
/*
|
|
* if previous extent entry covers the offset,
|
|
* we should return it instead of the bitmap entry
|
|
*/
|
|
n = &entry->offset_index;
|
|
while (1) {
|
|
n = rb_prev(n);
|
|
if (!n)
|
|
break;
|
|
prev = rb_entry(n, struct btrfs_free_space,
|
|
offset_index);
|
|
if (!prev->bitmap) {
|
|
if (prev->offset + prev->bytes > offset)
|
|
entry = prev;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return entry;
|
|
}
|
|
|
|
if (!prev)
|
|
return NULL;
|
|
|
|
/* find last entry before the 'offset' */
|
|
entry = prev;
|
|
if (entry->offset > offset) {
|
|
n = rb_prev(&entry->offset_index);
|
|
if (n) {
|
|
entry = rb_entry(n, struct btrfs_free_space,
|
|
offset_index);
|
|
BUG_ON(entry->offset > offset);
|
|
} else {
|
|
if (fuzzy)
|
|
return entry;
|
|
else
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
if (entry->bitmap) {
|
|
n = &entry->offset_index;
|
|
while (1) {
|
|
n = rb_prev(n);
|
|
if (!n)
|
|
break;
|
|
prev = rb_entry(n, struct btrfs_free_space,
|
|
offset_index);
|
|
if (!prev->bitmap) {
|
|
if (prev->offset + prev->bytes > offset)
|
|
return prev;
|
|
break;
|
|
}
|
|
}
|
|
if (entry->offset + BITS_PER_BITMAP *
|
|
block_group->sectorsize > offset)
|
|
return entry;
|
|
} else if (entry->offset + entry->bytes > offset)
|
|
return entry;
|
|
|
|
if (!fuzzy)
|
|
return NULL;
|
|
|
|
while (1) {
|
|
if (entry->bitmap) {
|
|
if (entry->offset + BITS_PER_BITMAP *
|
|
block_group->sectorsize > offset)
|
|
break;
|
|
} else {
|
|
if (entry->offset + entry->bytes > offset)
|
|
break;
|
|
}
|
|
|
|
n = rb_next(&entry->offset_index);
|
|
if (!n)
|
|
return NULL;
|
|
entry = rb_entry(n, struct btrfs_free_space, offset_index);
|
|
}
|
|
return entry;
|
|
}
|
|
|
|
static inline void
|
|
__unlink_free_space(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info)
|
|
{
|
|
rb_erase(&info->offset_index, &block_group->free_space_offset);
|
|
block_group->free_extents--;
|
|
}
|
|
|
|
static void unlink_free_space(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info)
|
|
{
|
|
__unlink_free_space(block_group, info);
|
|
block_group->free_space -= info->bytes;
|
|
}
|
|
|
|
static int link_free_space(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info)
|
|
{
|
|
int ret = 0;
|
|
|
|
BUG_ON(!info->bitmap && !info->bytes);
|
|
ret = tree_insert_offset(&block_group->free_space_offset, info->offset,
|
|
&info->offset_index, (info->bitmap != NULL));
|
|
if (ret)
|
|
return ret;
|
|
|
|
block_group->free_space += info->bytes;
|
|
block_group->free_extents++;
|
|
return ret;
|
|
}
|
|
|
|
static void recalculate_thresholds(struct btrfs_block_group_cache *block_group)
|
|
{
|
|
u64 max_bytes;
|
|
u64 bitmap_bytes;
|
|
u64 extent_bytes;
|
|
u64 size = block_group->key.offset;
|
|
|
|
/*
|
|
* The goal is to keep the total amount of memory used per 1gb of space
|
|
* at or below 32k, so we need to adjust how much memory we allow to be
|
|
* used by extent based free space tracking
|
|
*/
|
|
if (size < 1024 * 1024 * 1024)
|
|
max_bytes = MAX_CACHE_BYTES_PER_GIG;
|
|
else
|
|
max_bytes = MAX_CACHE_BYTES_PER_GIG *
|
|
div64_u64(size, 1024 * 1024 * 1024);
|
|
|
|
/*
|
|
* we want to account for 1 more bitmap than what we have so we can make
|
|
* sure we don't go over our overall goal of MAX_CACHE_BYTES_PER_GIG as
|
|
* we add more bitmaps.
|
|
*/
|
|
bitmap_bytes = (block_group->total_bitmaps + 1) * PAGE_CACHE_SIZE;
|
|
|
|
if (bitmap_bytes >= max_bytes) {
|
|
block_group->extents_thresh = 0;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* we want the extent entry threshold to always be at most 1/2 the maxw
|
|
* bytes we can have, or whatever is less than that.
|
|
*/
|
|
extent_bytes = max_bytes - bitmap_bytes;
|
|
extent_bytes = min_t(u64, extent_bytes, div64_u64(max_bytes, 2));
|
|
|
|
block_group->extents_thresh =
|
|
div64_u64(extent_bytes, (sizeof(struct btrfs_free_space)));
|
|
}
|
|
|
|
static void bitmap_clear_bits(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info, u64 offset,
|
|
u64 bytes)
|
|
{
|
|
unsigned long start, end;
|
|
unsigned long i;
|
|
|
|
start = offset_to_bit(info->offset, block_group->sectorsize, offset);
|
|
end = start + bytes_to_bits(bytes, block_group->sectorsize);
|
|
BUG_ON(end > BITS_PER_BITMAP);
|
|
|
|
for (i = start; i < end; i++)
|
|
clear_bit(i, info->bitmap);
|
|
|
|
info->bytes -= bytes;
|
|
block_group->free_space -= bytes;
|
|
}
|
|
|
|
static void bitmap_set_bits(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info, u64 offset,
|
|
u64 bytes)
|
|
{
|
|
unsigned long start, end;
|
|
unsigned long i;
|
|
|
|
start = offset_to_bit(info->offset, block_group->sectorsize, offset);
|
|
end = start + bytes_to_bits(bytes, block_group->sectorsize);
|
|
BUG_ON(end > BITS_PER_BITMAP);
|
|
|
|
for (i = start; i < end; i++)
|
|
set_bit(i, info->bitmap);
|
|
|
|
info->bytes += bytes;
|
|
block_group->free_space += bytes;
|
|
}
|
|
|
|
static int search_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *bitmap_info, u64 *offset,
|
|
u64 *bytes)
|
|
{
|
|
unsigned long found_bits = 0;
|
|
unsigned long bits, i;
|
|
unsigned long next_zero;
|
|
|
|
i = offset_to_bit(bitmap_info->offset, block_group->sectorsize,
|
|
max_t(u64, *offset, bitmap_info->offset));
|
|
bits = bytes_to_bits(*bytes, block_group->sectorsize);
|
|
|
|
for (i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i);
|
|
i < BITS_PER_BITMAP;
|
|
i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i + 1)) {
|
|
next_zero = find_next_zero_bit(bitmap_info->bitmap,
|
|
BITS_PER_BITMAP, i);
|
|
if ((next_zero - i) >= bits) {
|
|
found_bits = next_zero - i;
|
|
break;
|
|
}
|
|
i = next_zero;
|
|
}
|
|
|
|
if (found_bits) {
|
|
*offset = (u64)(i * block_group->sectorsize) +
|
|
bitmap_info->offset;
|
|
*bytes = (u64)(found_bits) * block_group->sectorsize;
|
|
return 0;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
static struct btrfs_free_space *find_free_space(struct btrfs_block_group_cache
|
|
*block_group, u64 *offset,
|
|
u64 *bytes, int debug)
|
|
{
|
|
struct btrfs_free_space *entry;
|
|
struct rb_node *node;
|
|
int ret;
|
|
|
|
if (!block_group->free_space_offset.rb_node)
|
|
return NULL;
|
|
|
|
entry = tree_search_offset(block_group,
|
|
offset_to_bitmap(block_group, *offset),
|
|
0, 1);
|
|
if (!entry)
|
|
return NULL;
|
|
|
|
for (node = &entry->offset_index; node; node = rb_next(node)) {
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
if (entry->bytes < *bytes)
|
|
continue;
|
|
|
|
if (entry->bitmap) {
|
|
ret = search_bitmap(block_group, entry, offset, bytes);
|
|
if (!ret)
|
|
return entry;
|
|
continue;
|
|
}
|
|
|
|
*offset = entry->offset;
|
|
*bytes = entry->bytes;
|
|
return entry;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void add_new_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info, u64 offset)
|
|
{
|
|
u64 bytes_per_bg = BITS_PER_BITMAP * block_group->sectorsize;
|
|
int max_bitmaps = (int)div64_u64(block_group->key.offset +
|
|
bytes_per_bg - 1, bytes_per_bg);
|
|
BUG_ON(block_group->total_bitmaps >= max_bitmaps);
|
|
|
|
info->offset = offset_to_bitmap(block_group, offset);
|
|
info->bytes = 0;
|
|
link_free_space(block_group, info);
|
|
block_group->total_bitmaps++;
|
|
|
|
recalculate_thresholds(block_group);
|
|
}
|
|
|
|
static void free_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *bitmap_info)
|
|
{
|
|
unlink_free_space(block_group, bitmap_info);
|
|
kfree(bitmap_info->bitmap);
|
|
kmem_cache_free(btrfs_free_space_cachep, bitmap_info);
|
|
block_group->total_bitmaps--;
|
|
recalculate_thresholds(block_group);
|
|
}
|
|
|
|
static noinline int remove_from_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *bitmap_info,
|
|
u64 *offset, u64 *bytes)
|
|
{
|
|
u64 end;
|
|
u64 search_start, search_bytes;
|
|
int ret;
|
|
|
|
again:
|
|
end = bitmap_info->offset +
|
|
(u64)(BITS_PER_BITMAP * block_group->sectorsize) - 1;
|
|
|
|
/*
|
|
* XXX - this can go away after a few releases.
|
|
*
|
|
* since the only user of btrfs_remove_free_space is the tree logging
|
|
* stuff, and the only way to test that is under crash conditions, we
|
|
* want to have this debug stuff here just in case somethings not
|
|
* working. Search the bitmap for the space we are trying to use to
|
|
* make sure its actually there. If its not there then we need to stop
|
|
* because something has gone wrong.
|
|
*/
|
|
search_start = *offset;
|
|
search_bytes = *bytes;
|
|
search_bytes = min(search_bytes, end - search_start + 1);
|
|
ret = search_bitmap(block_group, bitmap_info, &search_start,
|
|
&search_bytes);
|
|
BUG_ON(ret < 0 || search_start != *offset);
|
|
|
|
if (*offset > bitmap_info->offset && *offset + *bytes > end) {
|
|
bitmap_clear_bits(block_group, bitmap_info, *offset,
|
|
end - *offset + 1);
|
|
*bytes -= end - *offset + 1;
|
|
*offset = end + 1;
|
|
} else if (*offset >= bitmap_info->offset && *offset + *bytes <= end) {
|
|
bitmap_clear_bits(block_group, bitmap_info, *offset, *bytes);
|
|
*bytes = 0;
|
|
}
|
|
|
|
if (*bytes) {
|
|
struct rb_node *next = rb_next(&bitmap_info->offset_index);
|
|
if (!bitmap_info->bytes)
|
|
free_bitmap(block_group, bitmap_info);
|
|
|
|
/*
|
|
* no entry after this bitmap, but we still have bytes to
|
|
* remove, so something has gone wrong.
|
|
*/
|
|
if (!next)
|
|
return -EINVAL;
|
|
|
|
bitmap_info = rb_entry(next, struct btrfs_free_space,
|
|
offset_index);
|
|
|
|
/*
|
|
* if the next entry isn't a bitmap we need to return to let the
|
|
* extent stuff do its work.
|
|
*/
|
|
if (!bitmap_info->bitmap)
|
|
return -EAGAIN;
|
|
|
|
/*
|
|
* Ok the next item is a bitmap, but it may not actually hold
|
|
* the information for the rest of this free space stuff, so
|
|
* look for it, and if we don't find it return so we can try
|
|
* everything over again.
|
|
*/
|
|
search_start = *offset;
|
|
search_bytes = *bytes;
|
|
ret = search_bitmap(block_group, bitmap_info, &search_start,
|
|
&search_bytes);
|
|
if (ret < 0 || search_start != *offset)
|
|
return -EAGAIN;
|
|
|
|
goto again;
|
|
} else if (!bitmap_info->bytes)
|
|
free_bitmap(block_group, bitmap_info);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int insert_into_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info)
|
|
{
|
|
struct btrfs_free_space *bitmap_info;
|
|
int added = 0;
|
|
u64 bytes, offset, end;
|
|
int ret;
|
|
|
|
/*
|
|
* If we are below the extents threshold then we can add this as an
|
|
* extent, and don't have to deal with the bitmap
|
|
*/
|
|
if (block_group->free_extents < block_group->extents_thresh) {
|
|
/*
|
|
* If this block group has some small extents we don't want to
|
|
* use up all of our free slots in the cache with them, we want
|
|
* to reserve them to larger extents, however if we have plent
|
|
* of cache left then go ahead an dadd them, no sense in adding
|
|
* the overhead of a bitmap if we don't have to.
|
|
*/
|
|
if (info->bytes <= block_group->sectorsize * 4) {
|
|
if (block_group->free_extents * 2 <=
|
|
block_group->extents_thresh)
|
|
return 0;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* some block groups are so tiny they can't be enveloped by a bitmap, so
|
|
* don't even bother to create a bitmap for this
|
|
*/
|
|
if (BITS_PER_BITMAP * block_group->sectorsize >
|
|
block_group->key.offset)
|
|
return 0;
|
|
|
|
bytes = info->bytes;
|
|
offset = info->offset;
|
|
|
|
again:
|
|
bitmap_info = tree_search_offset(block_group,
|
|
offset_to_bitmap(block_group, offset),
|
|
1, 0);
|
|
if (!bitmap_info) {
|
|
BUG_ON(added);
|
|
goto new_bitmap;
|
|
}
|
|
|
|
end = bitmap_info->offset +
|
|
(u64)(BITS_PER_BITMAP * block_group->sectorsize);
|
|
|
|
if (offset >= bitmap_info->offset && offset + bytes > end) {
|
|
bitmap_set_bits(block_group, bitmap_info, offset,
|
|
end - offset);
|
|
bytes -= end - offset;
|
|
offset = end;
|
|
added = 0;
|
|
} else if (offset >= bitmap_info->offset && offset + bytes <= end) {
|
|
bitmap_set_bits(block_group, bitmap_info, offset, bytes);
|
|
bytes = 0;
|
|
} else {
|
|
BUG();
|
|
}
|
|
|
|
if (!bytes) {
|
|
ret = 1;
|
|
goto out;
|
|
} else
|
|
goto again;
|
|
|
|
new_bitmap:
|
|
if (info && info->bitmap) {
|
|
add_new_bitmap(block_group, info, offset);
|
|
added = 1;
|
|
info = NULL;
|
|
goto again;
|
|
} else {
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
/* no pre-allocated info, allocate a new one */
|
|
if (!info) {
|
|
info = kmem_cache_zalloc(btrfs_free_space_cachep,
|
|
GFP_NOFS);
|
|
if (!info) {
|
|
spin_lock(&block_group->tree_lock);
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* allocate the bitmap */
|
|
info->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS);
|
|
spin_lock(&block_group->tree_lock);
|
|
if (!info->bitmap) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
goto again;
|
|
}
|
|
|
|
out:
|
|
if (info) {
|
|
if (info->bitmap)
|
|
kfree(info->bitmap);
|
|
kmem_cache_free(btrfs_free_space_cachep, info);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
bool try_merge_free_space(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *info, bool update_stat)
|
|
{
|
|
struct btrfs_free_space *left_info;
|
|
struct btrfs_free_space *right_info;
|
|
bool merged = false;
|
|
u64 offset = info->offset;
|
|
u64 bytes = info->bytes;
|
|
|
|
/*
|
|
* first we want to see if there is free space adjacent to the range we
|
|
* are adding, if there is remove that struct and add a new one to
|
|
* cover the entire range
|
|
*/
|
|
right_info = tree_search_offset(block_group, offset + bytes, 0, 0);
|
|
if (right_info && rb_prev(&right_info->offset_index))
|
|
left_info = rb_entry(rb_prev(&right_info->offset_index),
|
|
struct btrfs_free_space, offset_index);
|
|
else
|
|
left_info = tree_search_offset(block_group, offset - 1, 0, 0);
|
|
|
|
if (right_info && !right_info->bitmap) {
|
|
if (update_stat)
|
|
unlink_free_space(block_group, right_info);
|
|
else
|
|
__unlink_free_space(block_group, right_info);
|
|
info->bytes += right_info->bytes;
|
|
kmem_cache_free(btrfs_free_space_cachep, right_info);
|
|
merged = true;
|
|
}
|
|
|
|
if (left_info && !left_info->bitmap &&
|
|
left_info->offset + left_info->bytes == offset) {
|
|
if (update_stat)
|
|
unlink_free_space(block_group, left_info);
|
|
else
|
|
__unlink_free_space(block_group, left_info);
|
|
info->offset = left_info->offset;
|
|
info->bytes += left_info->bytes;
|
|
kmem_cache_free(btrfs_free_space_cachep, left_info);
|
|
merged = true;
|
|
}
|
|
|
|
return merged;
|
|
}
|
|
|
|
int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
|
|
u64 offset, u64 bytes)
|
|
{
|
|
struct btrfs_free_space *info;
|
|
int ret = 0;
|
|
|
|
info = kmem_cache_zalloc(btrfs_free_space_cachep, GFP_NOFS);
|
|
if (!info)
|
|
return -ENOMEM;
|
|
|
|
info->offset = offset;
|
|
info->bytes = bytes;
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
|
|
if (try_merge_free_space(block_group, info, true))
|
|
goto link;
|
|
|
|
/*
|
|
* There was no extent directly to the left or right of this new
|
|
* extent then we know we're going to have to allocate a new extent, so
|
|
* before we do that see if we need to drop this into a bitmap
|
|
*/
|
|
ret = insert_into_bitmap(block_group, info);
|
|
if (ret < 0) {
|
|
goto out;
|
|
} else if (ret) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
link:
|
|
ret = link_free_space(block_group, info);
|
|
if (ret)
|
|
kmem_cache_free(btrfs_free_space_cachep, info);
|
|
out:
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
if (ret) {
|
|
printk(KERN_CRIT "btrfs: unable to add free space :%d\n", ret);
|
|
BUG_ON(ret == -EEXIST);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
|
|
u64 offset, u64 bytes)
|
|
{
|
|
struct btrfs_free_space *info;
|
|
struct btrfs_free_space *next_info = NULL;
|
|
int ret = 0;
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
|
|
again:
|
|
info = tree_search_offset(block_group, offset, 0, 0);
|
|
if (!info) {
|
|
/*
|
|
* oops didn't find an extent that matched the space we wanted
|
|
* to remove, look for a bitmap instead
|
|
*/
|
|
info = tree_search_offset(block_group,
|
|
offset_to_bitmap(block_group, offset),
|
|
1, 0);
|
|
if (!info) {
|
|
WARN_ON(1);
|
|
goto out_lock;
|
|
}
|
|
}
|
|
|
|
if (info->bytes < bytes && rb_next(&info->offset_index)) {
|
|
u64 end;
|
|
next_info = rb_entry(rb_next(&info->offset_index),
|
|
struct btrfs_free_space,
|
|
offset_index);
|
|
|
|
if (next_info->bitmap)
|
|
end = next_info->offset + BITS_PER_BITMAP *
|
|
block_group->sectorsize - 1;
|
|
else
|
|
end = next_info->offset + next_info->bytes;
|
|
|
|
if (next_info->bytes < bytes ||
|
|
next_info->offset > offset || offset > end) {
|
|
printk(KERN_CRIT "Found free space at %llu, size %llu,"
|
|
" trying to use %llu\n",
|
|
(unsigned long long)info->offset,
|
|
(unsigned long long)info->bytes,
|
|
(unsigned long long)bytes);
|
|
WARN_ON(1);
|
|
ret = -EINVAL;
|
|
goto out_lock;
|
|
}
|
|
|
|
info = next_info;
|
|
}
|
|
|
|
if (info->bytes == bytes) {
|
|
unlink_free_space(block_group, info);
|
|
if (info->bitmap) {
|
|
kfree(info->bitmap);
|
|
block_group->total_bitmaps--;
|
|
}
|
|
kmem_cache_free(btrfs_free_space_cachep, info);
|
|
goto out_lock;
|
|
}
|
|
|
|
if (!info->bitmap && info->offset == offset) {
|
|
unlink_free_space(block_group, info);
|
|
info->offset += bytes;
|
|
info->bytes -= bytes;
|
|
link_free_space(block_group, info);
|
|
goto out_lock;
|
|
}
|
|
|
|
if (!info->bitmap && info->offset <= offset &&
|
|
info->offset + info->bytes >= offset + bytes) {
|
|
u64 old_start = info->offset;
|
|
/*
|
|
* we're freeing space in the middle of the info,
|
|
* this can happen during tree log replay
|
|
*
|
|
* first unlink the old info and then
|
|
* insert it again after the hole we're creating
|
|
*/
|
|
unlink_free_space(block_group, info);
|
|
if (offset + bytes < info->offset + info->bytes) {
|
|
u64 old_end = info->offset + info->bytes;
|
|
|
|
info->offset = offset + bytes;
|
|
info->bytes = old_end - info->offset;
|
|
ret = link_free_space(block_group, info);
|
|
WARN_ON(ret);
|
|
if (ret)
|
|
goto out_lock;
|
|
} else {
|
|
/* the hole we're creating ends at the end
|
|
* of the info struct, just free the info
|
|
*/
|
|
kmem_cache_free(btrfs_free_space_cachep, info);
|
|
}
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
/* step two, insert a new info struct to cover
|
|
* anything before the hole
|
|
*/
|
|
ret = btrfs_add_free_space(block_group, old_start,
|
|
offset - old_start);
|
|
WARN_ON(ret);
|
|
goto out;
|
|
}
|
|
|
|
ret = remove_from_bitmap(block_group, info, &offset, &bytes);
|
|
if (ret == -EAGAIN)
|
|
goto again;
|
|
BUG_ON(ret);
|
|
out_lock:
|
|
spin_unlock(&block_group->tree_lock);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group,
|
|
u64 bytes)
|
|
{
|
|
struct btrfs_free_space *info;
|
|
struct rb_node *n;
|
|
int count = 0;
|
|
|
|
for (n = rb_first(&block_group->free_space_offset); n; n = rb_next(n)) {
|
|
info = rb_entry(n, struct btrfs_free_space, offset_index);
|
|
if (info->bytes >= bytes)
|
|
count++;
|
|
printk(KERN_CRIT "entry offset %llu, bytes %llu, bitmap %s\n",
|
|
(unsigned long long)info->offset,
|
|
(unsigned long long)info->bytes,
|
|
(info->bitmap) ? "yes" : "no");
|
|
}
|
|
printk(KERN_INFO "block group has cluster?: %s\n",
|
|
list_empty(&block_group->cluster_list) ? "no" : "yes");
|
|
printk(KERN_INFO "%d blocks of free space at or bigger than bytes is"
|
|
"\n", count);
|
|
}
|
|
|
|
u64 btrfs_block_group_free_space(struct btrfs_block_group_cache *block_group)
|
|
{
|
|
struct btrfs_free_space *info;
|
|
struct rb_node *n;
|
|
u64 ret = 0;
|
|
|
|
for (n = rb_first(&block_group->free_space_offset); n;
|
|
n = rb_next(n)) {
|
|
info = rb_entry(n, struct btrfs_free_space, offset_index);
|
|
ret += info->bytes;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* for a given cluster, put all of its extents back into the free
|
|
* space cache. If the block group passed doesn't match the block group
|
|
* pointed to by the cluster, someone else raced in and freed the
|
|
* cluster already. In that case, we just return without changing anything
|
|
*/
|
|
static int
|
|
__btrfs_return_cluster_to_free_space(
|
|
struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster)
|
|
{
|
|
struct btrfs_free_space *entry;
|
|
struct rb_node *node;
|
|
|
|
spin_lock(&cluster->lock);
|
|
if (cluster->block_group != block_group)
|
|
goto out;
|
|
|
|
cluster->block_group = NULL;
|
|
cluster->window_start = 0;
|
|
list_del_init(&cluster->block_group_list);
|
|
|
|
node = rb_first(&cluster->root);
|
|
while (node) {
|
|
bool bitmap;
|
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
node = rb_next(&entry->offset_index);
|
|
rb_erase(&entry->offset_index, &cluster->root);
|
|
|
|
bitmap = (entry->bitmap != NULL);
|
|
if (!bitmap)
|
|
try_merge_free_space(block_group, entry, false);
|
|
tree_insert_offset(&block_group->free_space_offset,
|
|
entry->offset, &entry->offset_index, bitmap);
|
|
}
|
|
cluster->root = RB_ROOT;
|
|
|
|
out:
|
|
spin_unlock(&cluster->lock);
|
|
btrfs_put_block_group(block_group);
|
|
return 0;
|
|
}
|
|
|
|
void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group)
|
|
{
|
|
struct btrfs_free_space *info;
|
|
struct rb_node *node;
|
|
struct btrfs_free_cluster *cluster;
|
|
struct list_head *head;
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
while ((head = block_group->cluster_list.next) !=
|
|
&block_group->cluster_list) {
|
|
cluster = list_entry(head, struct btrfs_free_cluster,
|
|
block_group_list);
|
|
|
|
WARN_ON(cluster->block_group != block_group);
|
|
__btrfs_return_cluster_to_free_space(block_group, cluster);
|
|
if (need_resched()) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
cond_resched();
|
|
spin_lock(&block_group->tree_lock);
|
|
}
|
|
}
|
|
|
|
while ((node = rb_last(&block_group->free_space_offset)) != NULL) {
|
|
info = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
if (!info->bitmap) {
|
|
unlink_free_space(block_group, info);
|
|
kmem_cache_free(btrfs_free_space_cachep, info);
|
|
} else {
|
|
free_bitmap(block_group, info);
|
|
}
|
|
|
|
if (need_resched()) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
cond_resched();
|
|
spin_lock(&block_group->tree_lock);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&block_group->tree_lock);
|
|
}
|
|
|
|
u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
|
|
u64 offset, u64 bytes, u64 empty_size)
|
|
{
|
|
struct btrfs_free_space *entry = NULL;
|
|
u64 bytes_search = bytes + empty_size;
|
|
u64 ret = 0;
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
entry = find_free_space(block_group, &offset, &bytes_search, 0);
|
|
if (!entry)
|
|
goto out;
|
|
|
|
ret = offset;
|
|
if (entry->bitmap) {
|
|
bitmap_clear_bits(block_group, entry, offset, bytes);
|
|
if (!entry->bytes)
|
|
free_bitmap(block_group, entry);
|
|
} else {
|
|
unlink_free_space(block_group, entry);
|
|
entry->offset += bytes;
|
|
entry->bytes -= bytes;
|
|
if (!entry->bytes)
|
|
kmem_cache_free(btrfs_free_space_cachep, entry);
|
|
else
|
|
link_free_space(block_group, entry);
|
|
}
|
|
|
|
out:
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* given a cluster, put all of its extents back into the free space
|
|
* cache. If a block group is passed, this function will only free
|
|
* a cluster that belongs to the passed block group.
|
|
*
|
|
* Otherwise, it'll get a reference on the block group pointed to by the
|
|
* cluster and remove the cluster from it.
|
|
*/
|
|
int btrfs_return_cluster_to_free_space(
|
|
struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster)
|
|
{
|
|
int ret;
|
|
|
|
/* first, get a safe pointer to the block group */
|
|
spin_lock(&cluster->lock);
|
|
if (!block_group) {
|
|
block_group = cluster->block_group;
|
|
if (!block_group) {
|
|
spin_unlock(&cluster->lock);
|
|
return 0;
|
|
}
|
|
} else if (cluster->block_group != block_group) {
|
|
/* someone else has already freed it don't redo their work */
|
|
spin_unlock(&cluster->lock);
|
|
return 0;
|
|
}
|
|
atomic_inc(&block_group->count);
|
|
spin_unlock(&cluster->lock);
|
|
|
|
/* now return any extents the cluster had on it */
|
|
spin_lock(&block_group->tree_lock);
|
|
ret = __btrfs_return_cluster_to_free_space(block_group, cluster);
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
/* finally drop our ref */
|
|
btrfs_put_block_group(block_group);
|
|
return ret;
|
|
}
|
|
|
|
static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster,
|
|
struct btrfs_free_space *entry,
|
|
u64 bytes, u64 min_start)
|
|
{
|
|
int err;
|
|
u64 search_start = cluster->window_start;
|
|
u64 search_bytes = bytes;
|
|
u64 ret = 0;
|
|
|
|
search_start = min_start;
|
|
search_bytes = bytes;
|
|
|
|
err = search_bitmap(block_group, entry, &search_start,
|
|
&search_bytes);
|
|
if (err)
|
|
return 0;
|
|
|
|
ret = search_start;
|
|
bitmap_clear_bits(block_group, entry, ret, bytes);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* given a cluster, try to allocate 'bytes' from it, returns 0
|
|
* if it couldn't find anything suitably large, or a logical disk offset
|
|
* if things worked out
|
|
*/
|
|
u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster, u64 bytes,
|
|
u64 min_start)
|
|
{
|
|
struct btrfs_free_space *entry = NULL;
|
|
struct rb_node *node;
|
|
u64 ret = 0;
|
|
|
|
spin_lock(&cluster->lock);
|
|
if (bytes > cluster->max_size)
|
|
goto out;
|
|
|
|
if (cluster->block_group != block_group)
|
|
goto out;
|
|
|
|
node = rb_first(&cluster->root);
|
|
if (!node)
|
|
goto out;
|
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
while(1) {
|
|
if (entry->bytes < bytes ||
|
|
(!entry->bitmap && entry->offset < min_start)) {
|
|
struct rb_node *node;
|
|
|
|
node = rb_next(&entry->offset_index);
|
|
if (!node)
|
|
break;
|
|
entry = rb_entry(node, struct btrfs_free_space,
|
|
offset_index);
|
|
continue;
|
|
}
|
|
|
|
if (entry->bitmap) {
|
|
ret = btrfs_alloc_from_bitmap(block_group,
|
|
cluster, entry, bytes,
|
|
min_start);
|
|
if (ret == 0) {
|
|
struct rb_node *node;
|
|
node = rb_next(&entry->offset_index);
|
|
if (!node)
|
|
break;
|
|
entry = rb_entry(node, struct btrfs_free_space,
|
|
offset_index);
|
|
continue;
|
|
}
|
|
} else {
|
|
|
|
ret = entry->offset;
|
|
|
|
entry->offset += bytes;
|
|
entry->bytes -= bytes;
|
|
}
|
|
|
|
if (entry->bytes == 0)
|
|
rb_erase(&entry->offset_index, &cluster->root);
|
|
break;
|
|
}
|
|
out:
|
|
spin_unlock(&cluster->lock);
|
|
|
|
if (!ret)
|
|
return 0;
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
|
|
block_group->free_space -= bytes;
|
|
if (entry->bytes == 0) {
|
|
block_group->free_extents--;
|
|
if (entry->bitmap) {
|
|
kfree(entry->bitmap);
|
|
block_group->total_bitmaps--;
|
|
recalculate_thresholds(block_group);
|
|
}
|
|
kmem_cache_free(btrfs_free_space_cachep, entry);
|
|
}
|
|
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int btrfs_bitmap_cluster(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_space *entry,
|
|
struct btrfs_free_cluster *cluster,
|
|
u64 offset, u64 bytes, u64 min_bytes)
|
|
{
|
|
unsigned long next_zero;
|
|
unsigned long i;
|
|
unsigned long search_bits;
|
|
unsigned long total_bits;
|
|
unsigned long found_bits;
|
|
unsigned long start = 0;
|
|
unsigned long total_found = 0;
|
|
int ret;
|
|
bool found = false;
|
|
|
|
i = offset_to_bit(entry->offset, block_group->sectorsize,
|
|
max_t(u64, offset, entry->offset));
|
|
search_bits = bytes_to_bits(bytes, block_group->sectorsize);
|
|
total_bits = bytes_to_bits(min_bytes, block_group->sectorsize);
|
|
|
|
again:
|
|
found_bits = 0;
|
|
for (i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i);
|
|
i < BITS_PER_BITMAP;
|
|
i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i + 1)) {
|
|
next_zero = find_next_zero_bit(entry->bitmap,
|
|
BITS_PER_BITMAP, i);
|
|
if (next_zero - i >= search_bits) {
|
|
found_bits = next_zero - i;
|
|
break;
|
|
}
|
|
i = next_zero;
|
|
}
|
|
|
|
if (!found_bits)
|
|
return -ENOSPC;
|
|
|
|
if (!found) {
|
|
start = i;
|
|
found = true;
|
|
}
|
|
|
|
total_found += found_bits;
|
|
|
|
if (cluster->max_size < found_bits * block_group->sectorsize)
|
|
cluster->max_size = found_bits * block_group->sectorsize;
|
|
|
|
if (total_found < total_bits) {
|
|
i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, next_zero);
|
|
if (i - start > total_bits * 2) {
|
|
total_found = 0;
|
|
cluster->max_size = 0;
|
|
found = false;
|
|
}
|
|
goto again;
|
|
}
|
|
|
|
cluster->window_start = start * block_group->sectorsize +
|
|
entry->offset;
|
|
rb_erase(&entry->offset_index, &block_group->free_space_offset);
|
|
ret = tree_insert_offset(&cluster->root, entry->offset,
|
|
&entry->offset_index, 1);
|
|
BUG_ON(ret);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This searches the block group for just extents to fill the cluster with.
|
|
*/
|
|
static int setup_cluster_no_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster,
|
|
u64 offset, u64 bytes, u64 min_bytes)
|
|
{
|
|
struct btrfs_free_space *first = NULL;
|
|
struct btrfs_free_space *entry = NULL;
|
|
struct btrfs_free_space *prev = NULL;
|
|
struct btrfs_free_space *last;
|
|
struct rb_node *node;
|
|
u64 window_start;
|
|
u64 window_free;
|
|
u64 max_extent;
|
|
u64 max_gap = 128 * 1024;
|
|
|
|
entry = tree_search_offset(block_group, offset, 0, 1);
|
|
if (!entry)
|
|
return -ENOSPC;
|
|
|
|
/*
|
|
* We don't want bitmaps, so just move along until we find a normal
|
|
* extent entry.
|
|
*/
|
|
while (entry->bitmap) {
|
|
node = rb_next(&entry->offset_index);
|
|
if (!node)
|
|
return -ENOSPC;
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
}
|
|
|
|
window_start = entry->offset;
|
|
window_free = entry->bytes;
|
|
max_extent = entry->bytes;
|
|
first = entry;
|
|
last = entry;
|
|
prev = entry;
|
|
|
|
while (window_free <= min_bytes) {
|
|
node = rb_next(&entry->offset_index);
|
|
if (!node)
|
|
return -ENOSPC;
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
|
|
if (entry->bitmap)
|
|
continue;
|
|
/*
|
|
* we haven't filled the empty size and the window is
|
|
* very large. reset and try again
|
|
*/
|
|
if (entry->offset - (prev->offset + prev->bytes) > max_gap ||
|
|
entry->offset - window_start > (min_bytes * 2)) {
|
|
first = entry;
|
|
window_start = entry->offset;
|
|
window_free = entry->bytes;
|
|
last = entry;
|
|
max_extent = entry->bytes;
|
|
} else {
|
|
last = entry;
|
|
window_free += entry->bytes;
|
|
if (entry->bytes > max_extent)
|
|
max_extent = entry->bytes;
|
|
}
|
|
prev = entry;
|
|
}
|
|
|
|
cluster->window_start = first->offset;
|
|
|
|
node = &first->offset_index;
|
|
|
|
/*
|
|
* now we've found our entries, pull them out of the free space
|
|
* cache and put them into the cluster rbtree
|
|
*/
|
|
do {
|
|
int ret;
|
|
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
node = rb_next(&entry->offset_index);
|
|
if (entry->bitmap)
|
|
continue;
|
|
|
|
rb_erase(&entry->offset_index, &block_group->free_space_offset);
|
|
ret = tree_insert_offset(&cluster->root, entry->offset,
|
|
&entry->offset_index, 0);
|
|
BUG_ON(ret);
|
|
} while (node && entry != last);
|
|
|
|
cluster->max_size = max_extent;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This specifically looks for bitmaps that may work in the cluster, we assume
|
|
* that we have already failed to find extents that will work.
|
|
*/
|
|
static int setup_cluster_bitmap(struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster,
|
|
u64 offset, u64 bytes, u64 min_bytes)
|
|
{
|
|
struct btrfs_free_space *entry;
|
|
struct rb_node *node;
|
|
int ret = -ENOSPC;
|
|
|
|
if (block_group->total_bitmaps == 0)
|
|
return -ENOSPC;
|
|
|
|
entry = tree_search_offset(block_group,
|
|
offset_to_bitmap(block_group, offset),
|
|
0, 1);
|
|
if (!entry)
|
|
return -ENOSPC;
|
|
|
|
node = &entry->offset_index;
|
|
do {
|
|
entry = rb_entry(node, struct btrfs_free_space, offset_index);
|
|
node = rb_next(&entry->offset_index);
|
|
if (!entry->bitmap)
|
|
continue;
|
|
if (entry->bytes < min_bytes)
|
|
continue;
|
|
ret = btrfs_bitmap_cluster(block_group, entry, cluster, offset,
|
|
bytes, min_bytes);
|
|
} while (ret && node);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* here we try to find a cluster of blocks in a block group. The goal
|
|
* is to find at least bytes free and up to empty_size + bytes free.
|
|
* We might not find them all in one contiguous area.
|
|
*
|
|
* returns zero and sets up cluster if things worked out, otherwise
|
|
* it returns -enospc
|
|
*/
|
|
int btrfs_find_space_cluster(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root,
|
|
struct btrfs_block_group_cache *block_group,
|
|
struct btrfs_free_cluster *cluster,
|
|
u64 offset, u64 bytes, u64 empty_size)
|
|
{
|
|
u64 min_bytes;
|
|
int ret;
|
|
|
|
/* for metadata, allow allocates with more holes */
|
|
if (btrfs_test_opt(root, SSD_SPREAD)) {
|
|
min_bytes = bytes + empty_size;
|
|
} else if (block_group->flags & BTRFS_BLOCK_GROUP_METADATA) {
|
|
/*
|
|
* we want to do larger allocations when we are
|
|
* flushing out the delayed refs, it helps prevent
|
|
* making more work as we go along.
|
|
*/
|
|
if (trans->transaction->delayed_refs.flushing)
|
|
min_bytes = max(bytes, (bytes + empty_size) >> 1);
|
|
else
|
|
min_bytes = max(bytes, (bytes + empty_size) >> 4);
|
|
} else
|
|
min_bytes = max(bytes, (bytes + empty_size) >> 2);
|
|
|
|
spin_lock(&block_group->tree_lock);
|
|
|
|
/*
|
|
* If we know we don't have enough space to make a cluster don't even
|
|
* bother doing all the work to try and find one.
|
|
*/
|
|
if (block_group->free_space < min_bytes) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
return -ENOSPC;
|
|
}
|
|
|
|
spin_lock(&cluster->lock);
|
|
|
|
/* someone already found a cluster, hooray */
|
|
if (cluster->block_group) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
ret = setup_cluster_no_bitmap(block_group, cluster, offset, bytes,
|
|
min_bytes);
|
|
if (ret)
|
|
ret = setup_cluster_bitmap(block_group, cluster, offset,
|
|
bytes, min_bytes);
|
|
|
|
if (!ret) {
|
|
atomic_inc(&block_group->count);
|
|
list_add_tail(&cluster->block_group_list,
|
|
&block_group->cluster_list);
|
|
cluster->block_group = block_group;
|
|
}
|
|
out:
|
|
spin_unlock(&cluster->lock);
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* simple code to zero out a cluster
|
|
*/
|
|
void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster)
|
|
{
|
|
spin_lock_init(&cluster->lock);
|
|
spin_lock_init(&cluster->refill_lock);
|
|
cluster->root = RB_ROOT;
|
|
cluster->max_size = 0;
|
|
INIT_LIST_HEAD(&cluster->block_group_list);
|
|
cluster->block_group = NULL;
|
|
}
|
|
|
|
int btrfs_trim_block_group(struct btrfs_block_group_cache *block_group,
|
|
u64 *trimmed, u64 start, u64 end, u64 minlen)
|
|
{
|
|
struct btrfs_free_space *entry = NULL;
|
|
struct btrfs_fs_info *fs_info = block_group->fs_info;
|
|
u64 bytes = 0;
|
|
u64 actually_trimmed;
|
|
int ret = 0;
|
|
|
|
*trimmed = 0;
|
|
|
|
while (start < end) {
|
|
spin_lock(&block_group->tree_lock);
|
|
|
|
if (block_group->free_space < minlen) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
break;
|
|
}
|
|
|
|
entry = tree_search_offset(block_group, start, 0, 1);
|
|
if (!entry)
|
|
entry = tree_search_offset(block_group,
|
|
offset_to_bitmap(block_group,
|
|
start),
|
|
1, 1);
|
|
|
|
if (!entry || entry->offset >= end) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
break;
|
|
}
|
|
|
|
if (entry->bitmap) {
|
|
ret = search_bitmap(block_group, entry, &start, &bytes);
|
|
if (!ret) {
|
|
if (start >= end) {
|
|
spin_unlock(&block_group->tree_lock);
|
|
break;
|
|
}
|
|
bytes = min(bytes, end - start);
|
|
bitmap_clear_bits(block_group, entry,
|
|
start, bytes);
|
|
if (entry->bytes == 0)
|
|
free_bitmap(block_group, entry);
|
|
} else {
|
|
start = entry->offset + BITS_PER_BITMAP *
|
|
block_group->sectorsize;
|
|
spin_unlock(&block_group->tree_lock);
|
|
ret = 0;
|
|
continue;
|
|
}
|
|
} else {
|
|
start = entry->offset;
|
|
bytes = min(entry->bytes, end - start);
|
|
unlink_free_space(block_group, entry);
|
|
kmem_cache_free(btrfs_free_space_cachep, entry);
|
|
}
|
|
|
|
spin_unlock(&block_group->tree_lock);
|
|
|
|
if (bytes >= minlen) {
|
|
int update_ret;
|
|
update_ret = btrfs_update_reserved_bytes(block_group,
|
|
bytes, 1, 1);
|
|
|
|
ret = btrfs_error_discard_extent(fs_info->extent_root,
|
|
start,
|
|
bytes,
|
|
&actually_trimmed);
|
|
|
|
btrfs_add_free_space(block_group,
|
|
start, bytes);
|
|
if (!update_ret)
|
|
btrfs_update_reserved_bytes(block_group,
|
|
bytes, 0, 1);
|
|
|
|
if (ret)
|
|
break;
|
|
*trimmed += actually_trimmed;
|
|
}
|
|
start += bytes;
|
|
bytes = 0;
|
|
|
|
if (fatal_signal_pending(current)) {
|
|
ret = -ERESTARTSYS;
|
|
break;
|
|
}
|
|
|
|
cond_resched();
|
|
}
|
|
|
|
return ret;
|
|
}
|