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* Copyright (C) 2008 Red Hat. All rights reserved.
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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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* 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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* 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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#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 <linux/ratelimit.h>
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#include "free-space-cache.h"
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#include "transaction.h"
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#include "extent_io.h"
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#include "inode-map.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 int link_free_space(struct btrfs_free_space_ctl *ctl,
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struct btrfs_free_space *info);
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static struct inode *__lookup_free_space_inode(struct btrfs_root *root,
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struct btrfs_path *path,
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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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key.objectid = BTRFS_FREE_SPACE_OBJECTID;
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ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
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btrfs_release_path(path);
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return ERR_PTR(-ENOENT);
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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(path);
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inode = btrfs_iget(root->fs_info->sb, &location, root, NULL);
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return ERR_PTR(-ENOENT);
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if (is_bad_inode(inode)) {
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return ERR_PTR(-ENOENT);
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inode->i_mapping->flags &= ~__GFP_FS;
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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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struct inode *inode = NULL;
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u32 flags = BTRFS_INODE_NODATASUM | BTRFS_INODE_NODATACOW;
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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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inode = __lookup_free_space_inode(root, path,
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block_group->key.objectid);
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spin_lock(&block_group->lock);
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if (!((BTRFS_I(inode)->flags & flags) == flags)) {
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printk(KERN_INFO "Old style space inode found, converting.\n");
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BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM |
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BTRFS_INODE_NODATACOW;
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block_group->disk_cache_state = BTRFS_DC_CLEAR;
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if (!block_group->iref) {
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block_group->inode = igrab(inode);
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block_group->iref = 1;
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spin_unlock(&block_group->lock);
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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_path *path, u64 ino, u64 offset)
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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 flags = BTRFS_INODE_NOCOMPRESS | BTRFS_INODE_PREALLOC;
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ret = btrfs_insert_empty_inode(trans, root, path, ino);
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/* We inline crc's for the free disk space cache */
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if (ino != BTRFS_FREE_INO_OBJECTID)
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flags |= BTRFS_INODE_NODATASUM | BTRFS_INODE_NODATACOW;
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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, flags);
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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, offset);
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btrfs_mark_buffer_dirty(leaf);
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btrfs_release_path(path);
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key.objectid = BTRFS_FREE_SPACE_OBJECTID;
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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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btrfs_release_path(path);
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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(path);
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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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ret = btrfs_find_free_objectid(root, &ino);
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return __create_free_space_inode(root, trans, path, ino,
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block_group->key.objectid);
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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 btrfs_block_rsv *rsv;
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rsv = trans->block_rsv;
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trans->block_rsv = &root->fs_info->global_block_rsv;
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/* 1 for slack space, 1 for updating the inode */
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needed_bytes = btrfs_calc_trunc_metadata_size(root, 1) +
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btrfs_calc_trans_metadata_size(root, 1);
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spin_lock(&trans->block_rsv->lock);
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if (trans->block_rsv->reserved < needed_bytes) {
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spin_unlock(&trans->block_rsv->lock);
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trans->block_rsv = rsv;
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spin_unlock(&trans->block_rsv->lock);
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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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* We don't need an orphan item because truncating the free space cache
226
* will never be split across transactions.
228
ret = btrfs_truncate_inode_items(trans, root, inode,
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0, BTRFS_EXTENT_DATA_KEY);
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trans->block_rsv = rsv;
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ret = btrfs_update_inode(trans, root, inode);
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trans->block_rsv = rsv;
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static int readahead_cache(struct inode *inode)
245
struct file_ra_state *ra;
246
unsigned long last_index;
248
ra = kzalloc(sizeof(*ra), GFP_NOFS);
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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);
266
struct btrfs_root *root;
270
unsigned check_crcs:1;
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static int io_ctl_init(struct io_ctl *io_ctl, struct inode *inode,
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struct btrfs_root *root)
276
memset(io_ctl, 0, sizeof(struct io_ctl));
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io_ctl->num_pages = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
279
io_ctl->pages = kzalloc(sizeof(struct page *) * io_ctl->num_pages,
284
if (btrfs_ino(inode) != BTRFS_FREE_INO_OBJECTID)
285
io_ctl->check_crcs = 1;
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static void io_ctl_free(struct io_ctl *io_ctl)
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kfree(io_ctl->pages);
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static void io_ctl_unmap_page(struct io_ctl *io_ctl)
297
kunmap(io_ctl->page);
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static void io_ctl_map_page(struct io_ctl *io_ctl, int clear)
305
WARN_ON(io_ctl->cur);
306
BUG_ON(io_ctl->index >= io_ctl->num_pages);
307
io_ctl->page = io_ctl->pages[io_ctl->index++];
308
io_ctl->cur = kmap(io_ctl->page);
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io_ctl->orig = io_ctl->cur;
310
io_ctl->size = PAGE_CACHE_SIZE;
312
memset(io_ctl->cur, 0, PAGE_CACHE_SIZE);
315
static void io_ctl_drop_pages(struct io_ctl *io_ctl)
319
io_ctl_unmap_page(io_ctl);
321
for (i = 0; i < io_ctl->num_pages; i++) {
322
ClearPageChecked(io_ctl->pages[i]);
323
unlock_page(io_ctl->pages[i]);
324
page_cache_release(io_ctl->pages[i]);
328
static int io_ctl_prepare_pages(struct io_ctl *io_ctl, struct inode *inode,
332
gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
335
for (i = 0; i < io_ctl->num_pages; i++) {
336
page = find_or_create_page(inode->i_mapping, i, mask);
338
io_ctl_drop_pages(io_ctl);
341
io_ctl->pages[i] = page;
342
if (uptodate && !PageUptodate(page)) {
343
btrfs_readpage(NULL, page);
345
if (!PageUptodate(page)) {
346
printk(KERN_ERR "btrfs: error reading free "
348
io_ctl_drop_pages(io_ctl);
354
for (i = 0; i < io_ctl->num_pages; i++) {
355
clear_page_dirty_for_io(io_ctl->pages[i]);
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set_page_extent_mapped(io_ctl->pages[i]);
362
static void io_ctl_set_generation(struct io_ctl *io_ctl, u64 generation)
366
io_ctl_map_page(io_ctl, 1);
369
* Skip the csum areas. If we don't check crcs then we just have a
370
* 64bit chunk at the front of the first page.
372
if (io_ctl->check_crcs) {
373
io_ctl->cur += (sizeof(u32) * io_ctl->num_pages);
374
io_ctl->size -= sizeof(u64) + (sizeof(u32) * io_ctl->num_pages);
376
io_ctl->cur += sizeof(u64);
377
io_ctl->size -= sizeof(u64) * 2;
381
*val = cpu_to_le64(generation);
382
io_ctl->cur += sizeof(u64);
385
static int io_ctl_check_generation(struct io_ctl *io_ctl, u64 generation)
390
* Skip the crc area. If we don't check crcs then we just have a 64bit
391
* chunk at the front of the first page.
393
if (io_ctl->check_crcs) {
394
io_ctl->cur += sizeof(u32) * io_ctl->num_pages;
395
io_ctl->size -= sizeof(u64) +
396
(sizeof(u32) * io_ctl->num_pages);
398
io_ctl->cur += sizeof(u64);
399
io_ctl->size -= sizeof(u64) * 2;
403
if (le64_to_cpu(*gen) != generation) {
404
printk_ratelimited(KERN_ERR "btrfs: space cache generation "
405
"(%Lu) does not match inode (%Lu)\n", *gen,
407
io_ctl_unmap_page(io_ctl);
410
io_ctl->cur += sizeof(u64);
414
static void io_ctl_set_crc(struct io_ctl *io_ctl, int index)
420
if (!io_ctl->check_crcs) {
421
io_ctl_unmap_page(io_ctl);
426
offset = sizeof(u32) * io_ctl->num_pages;;
428
crc = btrfs_csum_data(io_ctl->root, io_ctl->orig + offset, crc,
429
PAGE_CACHE_SIZE - offset);
430
btrfs_csum_final(crc, (char *)&crc);
431
io_ctl_unmap_page(io_ctl);
432
tmp = kmap(io_ctl->pages[0]);
435
kunmap(io_ctl->pages[0]);
438
static int io_ctl_check_crc(struct io_ctl *io_ctl, int index)
444
if (!io_ctl->check_crcs) {
445
io_ctl_map_page(io_ctl, 0);
450
offset = sizeof(u32) * io_ctl->num_pages;
452
tmp = kmap(io_ctl->pages[0]);
455
kunmap(io_ctl->pages[0]);
457
io_ctl_map_page(io_ctl, 0);
458
crc = btrfs_csum_data(io_ctl->root, io_ctl->orig + offset, crc,
459
PAGE_CACHE_SIZE - offset);
460
btrfs_csum_final(crc, (char *)&crc);
462
printk_ratelimited(KERN_ERR "btrfs: csum mismatch on free "
464
io_ctl_unmap_page(io_ctl);
471
static int io_ctl_add_entry(struct io_ctl *io_ctl, u64 offset, u64 bytes,
474
struct btrfs_free_space_entry *entry;
480
entry->offset = cpu_to_le64(offset);
481
entry->bytes = cpu_to_le64(bytes);
482
entry->type = (bitmap) ? BTRFS_FREE_SPACE_BITMAP :
483
BTRFS_FREE_SPACE_EXTENT;
484
io_ctl->cur += sizeof(struct btrfs_free_space_entry);
485
io_ctl->size -= sizeof(struct btrfs_free_space_entry);
487
if (io_ctl->size >= sizeof(struct btrfs_free_space_entry))
490
io_ctl_set_crc(io_ctl, io_ctl->index - 1);
492
/* No more pages to map */
493
if (io_ctl->index >= io_ctl->num_pages)
496
/* map the next page */
497
io_ctl_map_page(io_ctl, 1);
501
static int io_ctl_add_bitmap(struct io_ctl *io_ctl, void *bitmap)
507
* If we aren't at the start of the current page, unmap this one and
508
* map the next one if there is any left.
510
if (io_ctl->cur != io_ctl->orig) {
511
io_ctl_set_crc(io_ctl, io_ctl->index - 1);
512
if (io_ctl->index >= io_ctl->num_pages)
514
io_ctl_map_page(io_ctl, 0);
517
memcpy(io_ctl->cur, bitmap, PAGE_CACHE_SIZE);
518
io_ctl_set_crc(io_ctl, io_ctl->index - 1);
519
if (io_ctl->index < io_ctl->num_pages)
520
io_ctl_map_page(io_ctl, 0);
524
static void io_ctl_zero_remaining_pages(struct io_ctl *io_ctl)
527
* If we're not on the boundary we know we've modified the page and we
528
* need to crc the page.
530
if (io_ctl->cur != io_ctl->orig)
531
io_ctl_set_crc(io_ctl, io_ctl->index - 1);
533
io_ctl_unmap_page(io_ctl);
535
while (io_ctl->index < io_ctl->num_pages) {
536
io_ctl_map_page(io_ctl, 1);
537
io_ctl_set_crc(io_ctl, io_ctl->index - 1);
541
static int io_ctl_read_entry(struct io_ctl *io_ctl,
542
struct btrfs_free_space *entry, u8 *type)
544
struct btrfs_free_space_entry *e;
548
ret = io_ctl_check_crc(io_ctl, io_ctl->index);
554
entry->offset = le64_to_cpu(e->offset);
555
entry->bytes = le64_to_cpu(e->bytes);
557
io_ctl->cur += sizeof(struct btrfs_free_space_entry);
558
io_ctl->size -= sizeof(struct btrfs_free_space_entry);
560
if (io_ctl->size >= sizeof(struct btrfs_free_space_entry))
563
io_ctl_unmap_page(io_ctl);
568
static int io_ctl_read_bitmap(struct io_ctl *io_ctl,
569
struct btrfs_free_space *entry)
573
ret = io_ctl_check_crc(io_ctl, io_ctl->index);
577
memcpy(entry->bitmap, io_ctl->cur, PAGE_CACHE_SIZE);
578
io_ctl_unmap_page(io_ctl);
583
int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
584
struct btrfs_free_space_ctl *ctl,
585
struct btrfs_path *path, u64 offset)
587
struct btrfs_free_space_header *header;
588
struct extent_buffer *leaf;
589
struct io_ctl io_ctl;
590
struct btrfs_key key;
591
struct btrfs_free_space *e, *n;
592
struct list_head bitmaps;
599
INIT_LIST_HEAD(&bitmaps);
601
/* Nothing in the space cache, goodbye */
602
if (!i_size_read(inode))
605
key.objectid = BTRFS_FREE_SPACE_OBJECTID;
609
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
613
btrfs_release_path(path);
619
leaf = path->nodes[0];
620
header = btrfs_item_ptr(leaf, path->slots[0],
621
struct btrfs_free_space_header);
622
num_entries = btrfs_free_space_entries(leaf, header);
623
num_bitmaps = btrfs_free_space_bitmaps(leaf, header);
624
generation = btrfs_free_space_generation(leaf, header);
625
btrfs_release_path(path);
627
if (BTRFS_I(inode)->generation != generation) {
628
printk(KERN_ERR "btrfs: free space inode generation (%llu) did"
629
" not match free space cache generation (%llu)\n",
630
(unsigned long long)BTRFS_I(inode)->generation,
631
(unsigned long long)generation);
638
io_ctl_init(&io_ctl, inode, root);
639
ret = readahead_cache(inode);
643
ret = io_ctl_prepare_pages(&io_ctl, inode, 1);
647
ret = io_ctl_check_crc(&io_ctl, 0);
651
ret = io_ctl_check_generation(&io_ctl, generation);
655
while (num_entries) {
656
e = kmem_cache_zalloc(btrfs_free_space_cachep,
661
ret = io_ctl_read_entry(&io_ctl, e, &type);
663
kmem_cache_free(btrfs_free_space_cachep, e);
668
kmem_cache_free(btrfs_free_space_cachep, e);
672
if (type == BTRFS_FREE_SPACE_EXTENT) {
673
spin_lock(&ctl->tree_lock);
674
ret = link_free_space(ctl, e);
675
spin_unlock(&ctl->tree_lock);
677
printk(KERN_ERR "Duplicate entries in "
678
"free space cache, dumping\n");
679
kmem_cache_free(btrfs_free_space_cachep, e);
683
BUG_ON(!num_bitmaps);
685
e->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS);
688
btrfs_free_space_cachep, e);
691
spin_lock(&ctl->tree_lock);
692
ret = link_free_space(ctl, e);
693
ctl->total_bitmaps++;
694
ctl->op->recalc_thresholds(ctl);
695
spin_unlock(&ctl->tree_lock);
697
printk(KERN_ERR "Duplicate entries in "
698
"free space cache, dumping\n");
699
kmem_cache_free(btrfs_free_space_cachep, e);
702
list_add_tail(&e->list, &bitmaps);
708
io_ctl_unmap_page(&io_ctl);
711
* We add the bitmaps at the end of the entries in order that
712
* the bitmap entries are added to the cache.
714
list_for_each_entry_safe(e, n, &bitmaps, list) {
715
list_del_init(&e->list);
716
ret = io_ctl_read_bitmap(&io_ctl, e);
721
io_ctl_drop_pages(&io_ctl);
724
io_ctl_free(&io_ctl);
727
io_ctl_drop_pages(&io_ctl);
728
__btrfs_remove_free_space_cache(ctl);
732
int load_free_space_cache(struct btrfs_fs_info *fs_info,
733
struct btrfs_block_group_cache *block_group)
735
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
736
struct btrfs_root *root = fs_info->tree_root;
738
struct btrfs_path *path;
741
u64 used = btrfs_block_group_used(&block_group->item);
744
* If we're unmounting then just return, since this does a search on the
745
* normal root and not the commit root and we could deadlock.
747
if (btrfs_fs_closing(fs_info))
751
* If this block group has been marked to be cleared for one reason or
752
* another then we can't trust the on disk cache, so just return.
754
spin_lock(&block_group->lock);
755
if (block_group->disk_cache_state != BTRFS_DC_WRITTEN) {
756
spin_unlock(&block_group->lock);
759
spin_unlock(&block_group->lock);
761
path = btrfs_alloc_path();
765
inode = lookup_free_space_inode(root, block_group, path);
767
btrfs_free_path(path);
771
/* We may have converted the inode and made the cache invalid. */
772
spin_lock(&block_group->lock);
773
if (block_group->disk_cache_state != BTRFS_DC_WRITTEN) {
774
spin_unlock(&block_group->lock);
777
spin_unlock(&block_group->lock);
779
ret = __load_free_space_cache(fs_info->tree_root, inode, ctl,
780
path, block_group->key.objectid);
781
btrfs_free_path(path);
785
spin_lock(&ctl->tree_lock);
786
matched = (ctl->free_space == (block_group->key.offset - used -
787
block_group->bytes_super));
788
spin_unlock(&ctl->tree_lock);
791
__btrfs_remove_free_space_cache(ctl);
792
printk(KERN_ERR "block group %llu has an wrong amount of free "
793
"space\n", block_group->key.objectid);
798
/* This cache is bogus, make sure it gets cleared */
799
spin_lock(&block_group->lock);
800
block_group->disk_cache_state = BTRFS_DC_CLEAR;
801
spin_unlock(&block_group->lock);
804
printk(KERN_ERR "btrfs: failed to load free space cache "
805
"for block group %llu\n", block_group->key.objectid);
813
* __btrfs_write_out_cache - write out cached info to an inode
814
* @root - the root the inode belongs to
815
* @ctl - the free space cache we are going to write out
816
* @block_group - the block_group for this cache if it belongs to a block_group
817
* @trans - the trans handle
818
* @path - the path to use
819
* @offset - the offset for the key we'll insert
821
* This function writes out a free space cache struct to disk for quick recovery
822
* on mount. This will return 0 if it was successfull in writing the cache out,
823
* and -1 if it was not.
825
int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
826
struct btrfs_free_space_ctl *ctl,
827
struct btrfs_block_group_cache *block_group,
828
struct btrfs_trans_handle *trans,
829
struct btrfs_path *path, u64 offset)
831
struct btrfs_free_space_header *header;
832
struct extent_buffer *leaf;
833
struct rb_node *node;
834
struct list_head *pos, *n;
835
struct extent_state *cached_state = NULL;
836
struct btrfs_free_cluster *cluster = NULL;
837
struct extent_io_tree *unpin = NULL;
838
struct io_ctl io_ctl;
839
struct list_head bitmap_list;
840
struct btrfs_key key;
847
INIT_LIST_HEAD(&bitmap_list);
849
if (!i_size_read(inode))
852
io_ctl_init(&io_ctl, inode, root);
854
/* Get the cluster for this block_group if it exists */
855
if (block_group && !list_empty(&block_group->cluster_list))
856
cluster = list_entry(block_group->cluster_list.next,
857
struct btrfs_free_cluster,
861
* We shouldn't have switched the pinned extents yet so this is the
864
unpin = root->fs_info->pinned_extents;
866
/* Lock all pages first so we can lock the extent safely. */
867
io_ctl_prepare_pages(&io_ctl, inode, 0);
869
lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1,
870
0, &cached_state, GFP_NOFS);
873
* When searching for pinned extents, we need to start at our start
877
start = block_group->key.objectid;
879
node = rb_first(&ctl->free_space_offset);
880
if (!node && cluster) {
881
node = rb_first(&cluster->root);
885
/* Make sure we can fit our crcs into the first page */
886
if (io_ctl.check_crcs &&
887
(io_ctl.num_pages * sizeof(u32)) >= PAGE_CACHE_SIZE) {
892
io_ctl_set_generation(&io_ctl, trans->transid);
894
/* Write out the extent entries */
896
struct btrfs_free_space *e;
898
e = rb_entry(node, struct btrfs_free_space, offset_index);
901
ret = io_ctl_add_entry(&io_ctl, e->offset, e->bytes,
907
list_add_tail(&e->list, &bitmap_list);
910
node = rb_next(node);
911
if (!node && cluster) {
912
node = rb_first(&cluster->root);
918
* We want to add any pinned extents to our free space cache
919
* so we don't leak the space
921
while (block_group && (start < block_group->key.objectid +
922
block_group->key.offset)) {
923
ret = find_first_extent_bit(unpin, start, &start, &end,
930
/* This pinned extent is out of our range */
931
if (start >= block_group->key.objectid +
932
block_group->key.offset)
935
len = block_group->key.objectid +
936
block_group->key.offset - start;
937
len = min(len, end + 1 - start);
940
ret = io_ctl_add_entry(&io_ctl, start, len, NULL);
947
/* Write out the bitmaps */
948
list_for_each_safe(pos, n, &bitmap_list) {
949
struct btrfs_free_space *entry =
950
list_entry(pos, struct btrfs_free_space, list);
952
ret = io_ctl_add_bitmap(&io_ctl, entry->bitmap);
955
list_del_init(&entry->list);
958
/* Zero out the rest of the pages just to make sure */
959
io_ctl_zero_remaining_pages(&io_ctl);
961
ret = btrfs_dirty_pages(root, inode, io_ctl.pages, io_ctl.num_pages,
962
0, i_size_read(inode), &cached_state);
963
io_ctl_drop_pages(&io_ctl);
964
unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0,
965
i_size_read(inode) - 1, &cached_state, GFP_NOFS);
971
ret = filemap_write_and_wait(inode->i_mapping);
975
key.objectid = BTRFS_FREE_SPACE_OBJECTID;
979
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
981
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, inode->i_size - 1,
982
EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, NULL,
986
leaf = path->nodes[0];
988
struct btrfs_key found_key;
989
BUG_ON(!path->slots[0]);
991
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
992
if (found_key.objectid != BTRFS_FREE_SPACE_OBJECTID ||
993
found_key.offset != offset) {
994
clear_extent_bit(&BTRFS_I(inode)->io_tree, 0,
996
EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0,
998
btrfs_release_path(path);
1003
BTRFS_I(inode)->generation = trans->transid;
1004
header = btrfs_item_ptr(leaf, path->slots[0],
1005
struct btrfs_free_space_header);
1006
btrfs_set_free_space_entries(leaf, header, entries);
1007
btrfs_set_free_space_bitmaps(leaf, header, bitmaps);
1008
btrfs_set_free_space_generation(leaf, header, trans->transid);
1009
btrfs_mark_buffer_dirty(leaf);
1010
btrfs_release_path(path);
1014
io_ctl_free(&io_ctl);
1016
invalidate_inode_pages2(inode->i_mapping);
1017
BTRFS_I(inode)->generation = 0;
1019
btrfs_update_inode(trans, root, inode);
1023
list_for_each_safe(pos, n, &bitmap_list) {
1024
struct btrfs_free_space *entry =
1025
list_entry(pos, struct btrfs_free_space, list);
1026
list_del_init(&entry->list);
1028
io_ctl_drop_pages(&io_ctl);
1029
unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0,
1030
i_size_read(inode) - 1, &cached_state, GFP_NOFS);
1034
int btrfs_write_out_cache(struct btrfs_root *root,
1035
struct btrfs_trans_handle *trans,
1036
struct btrfs_block_group_cache *block_group,
1037
struct btrfs_path *path)
1039
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
1040
struct inode *inode;
1043
root = root->fs_info->tree_root;
1045
spin_lock(&block_group->lock);
1046
if (block_group->disk_cache_state < BTRFS_DC_SETUP) {
1047
spin_unlock(&block_group->lock);
1050
spin_unlock(&block_group->lock);
1052
inode = lookup_free_space_inode(root, block_group, path);
1056
ret = __btrfs_write_out_cache(root, inode, ctl, block_group, trans,
1057
path, block_group->key.objectid);
1059
spin_lock(&block_group->lock);
1060
block_group->disk_cache_state = BTRFS_DC_ERROR;
1061
spin_unlock(&block_group->lock);
1064
printk(KERN_ERR "btrfs: failed to write free space cace "
1065
"for block group %llu\n", block_group->key.objectid);
1073
static inline unsigned long offset_to_bit(u64 bitmap_start, u32 unit,
1076
BUG_ON(offset < bitmap_start);
1077
offset -= bitmap_start;
1078
return (unsigned long)(div_u64(offset, unit));
1081
static inline unsigned long bytes_to_bits(u64 bytes, u32 unit)
1083
return (unsigned long)(div_u64(bytes, unit));
1086
static inline u64 offset_to_bitmap(struct btrfs_free_space_ctl *ctl,
1090
u64 bytes_per_bitmap;
1092
bytes_per_bitmap = BITS_PER_BITMAP * ctl->unit;
1093
bitmap_start = offset - ctl->start;
1094
bitmap_start = div64_u64(bitmap_start, bytes_per_bitmap);
1095
bitmap_start *= bytes_per_bitmap;
1096
bitmap_start += ctl->start;
1098
return bitmap_start;
1101
static int tree_insert_offset(struct rb_root *root, u64 offset,
1102
struct rb_node *node, int bitmap)
1104
struct rb_node **p = &root->rb_node;
1105
struct rb_node *parent = NULL;
1106
struct btrfs_free_space *info;
1110
info = rb_entry(parent, struct btrfs_free_space, offset_index);
1112
if (offset < info->offset) {
1114
} else if (offset > info->offset) {
1115
p = &(*p)->rb_right;
1118
* we could have a bitmap entry and an extent entry
1119
* share the same offset. If this is the case, we want
1120
* the extent entry to always be found first if we do a
1121
* linear search through the tree, since we want to have
1122
* the quickest allocation time, and allocating from an
1123
* extent is faster than allocating from a bitmap. So
1124
* if we're inserting a bitmap and we find an entry at
1125
* this offset, we want to go right, or after this entry
1126
* logically. If we are inserting an extent and we've
1127
* found a bitmap, we want to go left, or before
1135
p = &(*p)->rb_right;
1137
if (!info->bitmap) {
1146
rb_link_node(node, parent, p);
1147
rb_insert_color(node, root);
1153
* searches the tree for the given offset.
1155
* fuzzy - If this is set, then we are trying to make an allocation, and we just
1156
* want a section that has at least bytes size and comes at or after the given
1159
static struct btrfs_free_space *
1160
tree_search_offset(struct btrfs_free_space_ctl *ctl,
1161
u64 offset, int bitmap_only, int fuzzy)
1163
struct rb_node *n = ctl->free_space_offset.rb_node;
1164
struct btrfs_free_space *entry, *prev = NULL;
1166
/* find entry that is closest to the 'offset' */
1173
entry = rb_entry(n, struct btrfs_free_space, offset_index);
1176
if (offset < entry->offset)
1178
else if (offset > entry->offset)
1191
* bitmap entry and extent entry may share same offset,
1192
* in that case, bitmap entry comes after extent entry.
1197
entry = rb_entry(n, struct btrfs_free_space, offset_index);
1198
if (entry->offset != offset)
1201
WARN_ON(!entry->bitmap);
1204
if (entry->bitmap) {
1206
* if previous extent entry covers the offset,
1207
* we should return it instead of the bitmap entry
1209
n = &entry->offset_index;
1214
prev = rb_entry(n, struct btrfs_free_space,
1216
if (!prev->bitmap) {
1217
if (prev->offset + prev->bytes > offset)
1229
/* find last entry before the 'offset' */
1231
if (entry->offset > offset) {
1232
n = rb_prev(&entry->offset_index);
1234
entry = rb_entry(n, struct btrfs_free_space,
1236
BUG_ON(entry->offset > offset);
1245
if (entry->bitmap) {
1246
n = &entry->offset_index;
1251
prev = rb_entry(n, struct btrfs_free_space,
1253
if (!prev->bitmap) {
1254
if (prev->offset + prev->bytes > offset)
1259
if (entry->offset + BITS_PER_BITMAP * ctl->unit > offset)
1261
} else if (entry->offset + entry->bytes > offset)
1268
if (entry->bitmap) {
1269
if (entry->offset + BITS_PER_BITMAP *
1273
if (entry->offset + entry->bytes > offset)
1277
n = rb_next(&entry->offset_index);
1280
entry = rb_entry(n, struct btrfs_free_space, offset_index);
1286
__unlink_free_space(struct btrfs_free_space_ctl *ctl,
1287
struct btrfs_free_space *info)
1289
rb_erase(&info->offset_index, &ctl->free_space_offset);
1290
ctl->free_extents--;
1293
static void unlink_free_space(struct btrfs_free_space_ctl *ctl,
1294
struct btrfs_free_space *info)
1296
__unlink_free_space(ctl, info);
1297
ctl->free_space -= info->bytes;
1300
static int link_free_space(struct btrfs_free_space_ctl *ctl,
1301
struct btrfs_free_space *info)
1305
BUG_ON(!info->bitmap && !info->bytes);
1306
ret = tree_insert_offset(&ctl->free_space_offset, info->offset,
1307
&info->offset_index, (info->bitmap != NULL));
1311
ctl->free_space += info->bytes;
1312
ctl->free_extents++;
1316
static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)
1318
struct btrfs_block_group_cache *block_group = ctl->private;
1322
u64 size = block_group->key.offset;
1323
u64 bytes_per_bg = BITS_PER_BITMAP * block_group->sectorsize;
1324
int max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg);
1326
BUG_ON(ctl->total_bitmaps > max_bitmaps);
1329
* The goal is to keep the total amount of memory used per 1gb of space
1330
* at or below 32k, so we need to adjust how much memory we allow to be
1331
* used by extent based free space tracking
1333
if (size < 1024 * 1024 * 1024)
1334
max_bytes = MAX_CACHE_BYTES_PER_GIG;
1336
max_bytes = MAX_CACHE_BYTES_PER_GIG *
1337
div64_u64(size, 1024 * 1024 * 1024);
1340
* we want to account for 1 more bitmap than what we have so we can make
1341
* sure we don't go over our overall goal of MAX_CACHE_BYTES_PER_GIG as
1342
* we add more bitmaps.
1344
bitmap_bytes = (ctl->total_bitmaps + 1) * PAGE_CACHE_SIZE;
1346
if (bitmap_bytes >= max_bytes) {
1347
ctl->extents_thresh = 0;
1352
* we want the extent entry threshold to always be at most 1/2 the maxw
1353
* bytes we can have, or whatever is less than that.
1355
extent_bytes = max_bytes - bitmap_bytes;
1356
extent_bytes = min_t(u64, extent_bytes, div64_u64(max_bytes, 2));
1358
ctl->extents_thresh =
1359
div64_u64(extent_bytes, (sizeof(struct btrfs_free_space)));
1362
static inline void __bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
1363
struct btrfs_free_space *info,
1364
u64 offset, u64 bytes)
1366
unsigned long start, count;
1368
start = offset_to_bit(info->offset, ctl->unit, offset);
1369
count = bytes_to_bits(bytes, ctl->unit);
1370
BUG_ON(start + count > BITS_PER_BITMAP);
1372
bitmap_clear(info->bitmap, start, count);
1374
info->bytes -= bytes;
1377
static void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
1378
struct btrfs_free_space *info, u64 offset,
1381
__bitmap_clear_bits(ctl, info, offset, bytes);
1382
ctl->free_space -= bytes;
1385
static void bitmap_set_bits(struct btrfs_free_space_ctl *ctl,
1386
struct btrfs_free_space *info, u64 offset,
1389
unsigned long start, count;
1391
start = offset_to_bit(info->offset, ctl->unit, offset);
1392
count = bytes_to_bits(bytes, ctl->unit);
1393
BUG_ON(start + count > BITS_PER_BITMAP);
1395
bitmap_set(info->bitmap, start, count);
1397
info->bytes += bytes;
1398
ctl->free_space += bytes;
1401
static int search_bitmap(struct btrfs_free_space_ctl *ctl,
1402
struct btrfs_free_space *bitmap_info, u64 *offset,
1405
unsigned long found_bits = 0;
1406
unsigned long bits, i;
1407
unsigned long next_zero;
1409
i = offset_to_bit(bitmap_info->offset, ctl->unit,
1410
max_t(u64, *offset, bitmap_info->offset));
1411
bits = bytes_to_bits(*bytes, ctl->unit);
1413
for (i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i);
1414
i < BITS_PER_BITMAP;
1415
i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i + 1)) {
1416
next_zero = find_next_zero_bit(bitmap_info->bitmap,
1417
BITS_PER_BITMAP, i);
1418
if ((next_zero - i) >= bits) {
1419
found_bits = next_zero - i;
1426
*offset = (u64)(i * ctl->unit) + bitmap_info->offset;
1427
*bytes = (u64)(found_bits) * ctl->unit;
1434
static struct btrfs_free_space *
1435
find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes)
1437
struct btrfs_free_space *entry;
1438
struct rb_node *node;
1441
if (!ctl->free_space_offset.rb_node)
1444
entry = tree_search_offset(ctl, offset_to_bitmap(ctl, *offset), 0, 1);
1448
for (node = &entry->offset_index; node; node = rb_next(node)) {
1449
entry = rb_entry(node, struct btrfs_free_space, offset_index);
1450
if (entry->bytes < *bytes)
1453
if (entry->bitmap) {
1454
ret = search_bitmap(ctl, entry, offset, bytes);
1460
*offset = entry->offset;
1461
*bytes = entry->bytes;
1468
static void add_new_bitmap(struct btrfs_free_space_ctl *ctl,
1469
struct btrfs_free_space *info, u64 offset)
1471
info->offset = offset_to_bitmap(ctl, offset);
1473
INIT_LIST_HEAD(&info->list);
1474
link_free_space(ctl, info);
1475
ctl->total_bitmaps++;
1477
ctl->op->recalc_thresholds(ctl);
1480
static void free_bitmap(struct btrfs_free_space_ctl *ctl,
1481
struct btrfs_free_space *bitmap_info)
1483
unlink_free_space(ctl, bitmap_info);
1484
kfree(bitmap_info->bitmap);
1485
kmem_cache_free(btrfs_free_space_cachep, bitmap_info);
1486
ctl->total_bitmaps--;
1487
ctl->op->recalc_thresholds(ctl);
1490
static noinline int remove_from_bitmap(struct btrfs_free_space_ctl *ctl,
1491
struct btrfs_free_space *bitmap_info,
1492
u64 *offset, u64 *bytes)
1495
u64 search_start, search_bytes;
1499
end = bitmap_info->offset + (u64)(BITS_PER_BITMAP * ctl->unit) - 1;
1502
* XXX - this can go away after a few releases.
1504
* since the only user of btrfs_remove_free_space is the tree logging
1505
* stuff, and the only way to test that is under crash conditions, we
1506
* want to have this debug stuff here just in case somethings not
1507
* working. Search the bitmap for the space we are trying to use to
1508
* make sure its actually there. If its not there then we need to stop
1509
* because something has gone wrong.
1511
search_start = *offset;
1512
search_bytes = *bytes;
1513
search_bytes = min(search_bytes, end - search_start + 1);
1514
ret = search_bitmap(ctl, bitmap_info, &search_start, &search_bytes);
1515
BUG_ON(ret < 0 || search_start != *offset);
1517
if (*offset > bitmap_info->offset && *offset + *bytes > end) {
1518
bitmap_clear_bits(ctl, bitmap_info, *offset, end - *offset + 1);
1519
*bytes -= end - *offset + 1;
1521
} else if (*offset >= bitmap_info->offset && *offset + *bytes <= end) {
1522
bitmap_clear_bits(ctl, bitmap_info, *offset, *bytes);
1527
struct rb_node *next = rb_next(&bitmap_info->offset_index);
1528
if (!bitmap_info->bytes)
1529
free_bitmap(ctl, bitmap_info);
1532
* no entry after this bitmap, but we still have bytes to
1533
* remove, so something has gone wrong.
1538
bitmap_info = rb_entry(next, struct btrfs_free_space,
1542
* if the next entry isn't a bitmap we need to return to let the
1543
* extent stuff do its work.
1545
if (!bitmap_info->bitmap)
1549
* Ok the next item is a bitmap, but it may not actually hold
1550
* the information for the rest of this free space stuff, so
1551
* look for it, and if we don't find it return so we can try
1552
* everything over again.
1554
search_start = *offset;
1555
search_bytes = *bytes;
1556
ret = search_bitmap(ctl, bitmap_info, &search_start,
1558
if (ret < 0 || search_start != *offset)
1562
} else if (!bitmap_info->bytes)
1563
free_bitmap(ctl, bitmap_info);
1568
static u64 add_bytes_to_bitmap(struct btrfs_free_space_ctl *ctl,
1569
struct btrfs_free_space *info, u64 offset,
1572
u64 bytes_to_set = 0;
1575
end = info->offset + (u64)(BITS_PER_BITMAP * ctl->unit);
1577
bytes_to_set = min(end - offset, bytes);
1579
bitmap_set_bits(ctl, info, offset, bytes_to_set);
1581
return bytes_to_set;
1585
static bool use_bitmap(struct btrfs_free_space_ctl *ctl,
1586
struct btrfs_free_space *info)
1588
struct btrfs_block_group_cache *block_group = ctl->private;
1591
* If we are below the extents threshold then we can add this as an
1592
* extent, and don't have to deal with the bitmap
1594
if (ctl->free_extents < ctl->extents_thresh) {
1596
* If this block group has some small extents we don't want to
1597
* use up all of our free slots in the cache with them, we want
1598
* to reserve them to larger extents, however if we have plent
1599
* of cache left then go ahead an dadd them, no sense in adding
1600
* the overhead of a bitmap if we don't have to.
1602
if (info->bytes <= block_group->sectorsize * 4) {
1603
if (ctl->free_extents * 2 <= ctl->extents_thresh)
1611
* some block groups are so tiny they can't be enveloped by a bitmap, so
1612
* don't even bother to create a bitmap for this
1614
if (BITS_PER_BITMAP * block_group->sectorsize >
1615
block_group->key.offset)
1621
static struct btrfs_free_space_op free_space_op = {
1622
.recalc_thresholds = recalculate_thresholds,
1623
.use_bitmap = use_bitmap,
1626
static int insert_into_bitmap(struct btrfs_free_space_ctl *ctl,
1627
struct btrfs_free_space *info)
1629
struct btrfs_free_space *bitmap_info;
1630
struct btrfs_block_group_cache *block_group = NULL;
1632
u64 bytes, offset, bytes_added;
1635
bytes = info->bytes;
1636
offset = info->offset;
1638
if (!ctl->op->use_bitmap(ctl, info))
1641
if (ctl->op == &free_space_op)
1642
block_group = ctl->private;
1645
* Since we link bitmaps right into the cluster we need to see if we
1646
* have a cluster here, and if so and it has our bitmap we need to add
1647
* the free space to that bitmap.
1649
if (block_group && !list_empty(&block_group->cluster_list)) {
1650
struct btrfs_free_cluster *cluster;
1651
struct rb_node *node;
1652
struct btrfs_free_space *entry;
1654
cluster = list_entry(block_group->cluster_list.next,
1655
struct btrfs_free_cluster,
1657
spin_lock(&cluster->lock);
1658
node = rb_first(&cluster->root);
1660
spin_unlock(&cluster->lock);
1661
goto no_cluster_bitmap;
1664
entry = rb_entry(node, struct btrfs_free_space, offset_index);
1665
if (!entry->bitmap) {
1666
spin_unlock(&cluster->lock);
1667
goto no_cluster_bitmap;
1670
if (entry->offset == offset_to_bitmap(ctl, offset)) {
1671
bytes_added = add_bytes_to_bitmap(ctl, entry,
1673
bytes -= bytes_added;
1674
offset += bytes_added;
1676
spin_unlock(&cluster->lock);
1684
bitmap_info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset),
1691
bytes_added = add_bytes_to_bitmap(ctl, bitmap_info, offset, bytes);
1692
bytes -= bytes_added;
1693
offset += bytes_added;
1703
if (info && info->bitmap) {
1704
add_new_bitmap(ctl, info, offset);
1709
spin_unlock(&ctl->tree_lock);
1711
/* no pre-allocated info, allocate a new one */
1713
info = kmem_cache_zalloc(btrfs_free_space_cachep,
1716
spin_lock(&ctl->tree_lock);
1722
/* allocate the bitmap */
1723
info->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS);
1724
spin_lock(&ctl->tree_lock);
1725
if (!info->bitmap) {
1735
kfree(info->bitmap);
1736
kmem_cache_free(btrfs_free_space_cachep, info);
1742
static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl,
1743
struct btrfs_free_space *info, bool update_stat)
1745
struct btrfs_free_space *left_info;
1746
struct btrfs_free_space *right_info;
1747
bool merged = false;
1748
u64 offset = info->offset;
1749
u64 bytes = info->bytes;
1752
* first we want to see if there is free space adjacent to the range we
1753
* are adding, if there is remove that struct and add a new one to
1754
* cover the entire range
1756
right_info = tree_search_offset(ctl, offset + bytes, 0, 0);
1757
if (right_info && rb_prev(&right_info->offset_index))
1758
left_info = rb_entry(rb_prev(&right_info->offset_index),
1759
struct btrfs_free_space, offset_index);
1761
left_info = tree_search_offset(ctl, offset - 1, 0, 0);
1763
if (right_info && !right_info->bitmap) {
1765
unlink_free_space(ctl, right_info);
1767
__unlink_free_space(ctl, right_info);
1768
info->bytes += right_info->bytes;
1769
kmem_cache_free(btrfs_free_space_cachep, right_info);
1773
if (left_info && !left_info->bitmap &&
1774
left_info->offset + left_info->bytes == offset) {
1776
unlink_free_space(ctl, left_info);
1778
__unlink_free_space(ctl, left_info);
1779
info->offset = left_info->offset;
1780
info->bytes += left_info->bytes;
1781
kmem_cache_free(btrfs_free_space_cachep, left_info);
1788
int __btrfs_add_free_space(struct btrfs_free_space_ctl *ctl,
1789
u64 offset, u64 bytes)
1791
struct btrfs_free_space *info;
1794
info = kmem_cache_zalloc(btrfs_free_space_cachep, GFP_NOFS);
1798
info->offset = offset;
1799
info->bytes = bytes;
1801
spin_lock(&ctl->tree_lock);
1803
if (try_merge_free_space(ctl, info, true))
1807
* There was no extent directly to the left or right of this new
1808
* extent then we know we're going to have to allocate a new extent, so
1809
* before we do that see if we need to drop this into a bitmap
1811
ret = insert_into_bitmap(ctl, info);
1819
ret = link_free_space(ctl, info);
1821
kmem_cache_free(btrfs_free_space_cachep, info);
1823
spin_unlock(&ctl->tree_lock);
1826
printk(KERN_CRIT "btrfs: unable to add free space :%d\n", ret);
1827
BUG_ON(ret == -EEXIST);
1833
int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
1834
u64 offset, u64 bytes)
1836
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
1837
struct btrfs_free_space *info;
1838
struct btrfs_free_space *next_info = NULL;
1841
spin_lock(&ctl->tree_lock);
1844
info = tree_search_offset(ctl, offset, 0, 0);
1847
* oops didn't find an extent that matched the space we wanted
1848
* to remove, look for a bitmap instead
1850
info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset),
1853
/* the tree logging code might be calling us before we
1854
* have fully loaded the free space rbtree for this
1855
* block group. So it is possible the entry won't
1856
* be in the rbtree yet at all. The caching code
1857
* will make sure not to put it in the rbtree if
1858
* the logging code has pinned it.
1864
if (info->bytes < bytes && rb_next(&info->offset_index)) {
1866
next_info = rb_entry(rb_next(&info->offset_index),
1867
struct btrfs_free_space,
1870
if (next_info->bitmap)
1871
end = next_info->offset +
1872
BITS_PER_BITMAP * ctl->unit - 1;
1874
end = next_info->offset + next_info->bytes;
1876
if (next_info->bytes < bytes ||
1877
next_info->offset > offset || offset > end) {
1878
printk(KERN_CRIT "Found free space at %llu, size %llu,"
1879
" trying to use %llu\n",
1880
(unsigned long long)info->offset,
1881
(unsigned long long)info->bytes,
1882
(unsigned long long)bytes);
1891
if (info->bytes == bytes) {
1892
unlink_free_space(ctl, info);
1894
kfree(info->bitmap);
1895
ctl->total_bitmaps--;
1897
kmem_cache_free(btrfs_free_space_cachep, info);
1902
if (!info->bitmap && info->offset == offset) {
1903
unlink_free_space(ctl, info);
1904
info->offset += bytes;
1905
info->bytes -= bytes;
1906
ret = link_free_space(ctl, info);
1911
if (!info->bitmap && info->offset <= offset &&
1912
info->offset + info->bytes >= offset + bytes) {
1913
u64 old_start = info->offset;
1915
* we're freeing space in the middle of the info,
1916
* this can happen during tree log replay
1918
* first unlink the old info and then
1919
* insert it again after the hole we're creating
1921
unlink_free_space(ctl, info);
1922
if (offset + bytes < info->offset + info->bytes) {
1923
u64 old_end = info->offset + info->bytes;
1925
info->offset = offset + bytes;
1926
info->bytes = old_end - info->offset;
1927
ret = link_free_space(ctl, info);
1932
/* the hole we're creating ends at the end
1933
* of the info struct, just free the info
1935
kmem_cache_free(btrfs_free_space_cachep, info);
1937
spin_unlock(&ctl->tree_lock);
1939
/* step two, insert a new info struct to cover
1940
* anything before the hole
1942
ret = btrfs_add_free_space(block_group, old_start,
1943
offset - old_start);
1948
ret = remove_from_bitmap(ctl, info, &offset, &bytes);
1953
spin_unlock(&ctl->tree_lock);
1958
void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group,
1961
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
1962
struct btrfs_free_space *info;
1966
for (n = rb_first(&ctl->free_space_offset); n; n = rb_next(n)) {
1967
info = rb_entry(n, struct btrfs_free_space, offset_index);
1968
if (info->bytes >= bytes)
1970
printk(KERN_CRIT "entry offset %llu, bytes %llu, bitmap %s\n",
1971
(unsigned long long)info->offset,
1972
(unsigned long long)info->bytes,
1973
(info->bitmap) ? "yes" : "no");
1975
printk(KERN_INFO "block group has cluster?: %s\n",
1976
list_empty(&block_group->cluster_list) ? "no" : "yes");
1977
printk(KERN_INFO "%d blocks of free space at or bigger than bytes is"
1981
void btrfs_init_free_space_ctl(struct btrfs_block_group_cache *block_group)
1983
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
1985
spin_lock_init(&ctl->tree_lock);
1986
ctl->unit = block_group->sectorsize;
1987
ctl->start = block_group->key.objectid;
1988
ctl->private = block_group;
1989
ctl->op = &free_space_op;
1992
* we only want to have 32k of ram per block group for keeping
1993
* track of free space, and if we pass 1/2 of that we want to
1994
* start converting things over to using bitmaps
1996
ctl->extents_thresh = ((1024 * 32) / 2) /
1997
sizeof(struct btrfs_free_space);
2001
* for a given cluster, put all of its extents back into the free
2002
* space cache. If the block group passed doesn't match the block group
2003
* pointed to by the cluster, someone else raced in and freed the
2004
* cluster already. In that case, we just return without changing anything
2007
__btrfs_return_cluster_to_free_space(
2008
struct btrfs_block_group_cache *block_group,
2009
struct btrfs_free_cluster *cluster)
2011
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2012
struct btrfs_free_space *entry;
2013
struct rb_node *node;
2015
spin_lock(&cluster->lock);
2016
if (cluster->block_group != block_group)
2019
cluster->block_group = NULL;
2020
cluster->window_start = 0;
2021
list_del_init(&cluster->block_group_list);
2023
node = rb_first(&cluster->root);
2027
entry = rb_entry(node, struct btrfs_free_space, offset_index);
2028
node = rb_next(&entry->offset_index);
2029
rb_erase(&entry->offset_index, &cluster->root);
2031
bitmap = (entry->bitmap != NULL);
2033
try_merge_free_space(ctl, entry, false);
2034
tree_insert_offset(&ctl->free_space_offset,
2035
entry->offset, &entry->offset_index, bitmap);
2037
cluster->root = RB_ROOT;
2040
spin_unlock(&cluster->lock);
2041
btrfs_put_block_group(block_group);
2045
void __btrfs_remove_free_space_cache_locked(struct btrfs_free_space_ctl *ctl)
2047
struct btrfs_free_space *info;
2048
struct rb_node *node;
2050
while ((node = rb_last(&ctl->free_space_offset)) != NULL) {
2051
info = rb_entry(node, struct btrfs_free_space, offset_index);
2052
if (!info->bitmap) {
2053
unlink_free_space(ctl, info);
2054
kmem_cache_free(btrfs_free_space_cachep, info);
2056
free_bitmap(ctl, info);
2058
if (need_resched()) {
2059
spin_unlock(&ctl->tree_lock);
2061
spin_lock(&ctl->tree_lock);
2066
void __btrfs_remove_free_space_cache(struct btrfs_free_space_ctl *ctl)
2068
spin_lock(&ctl->tree_lock);
2069
__btrfs_remove_free_space_cache_locked(ctl);
2070
spin_unlock(&ctl->tree_lock);
2073
void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group)
2075
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2076
struct btrfs_free_cluster *cluster;
2077
struct list_head *head;
2079
spin_lock(&ctl->tree_lock);
2080
while ((head = block_group->cluster_list.next) !=
2081
&block_group->cluster_list) {
2082
cluster = list_entry(head, struct btrfs_free_cluster,
2085
WARN_ON(cluster->block_group != block_group);
2086
__btrfs_return_cluster_to_free_space(block_group, cluster);
2087
if (need_resched()) {
2088
spin_unlock(&ctl->tree_lock);
2090
spin_lock(&ctl->tree_lock);
2093
__btrfs_remove_free_space_cache_locked(ctl);
2094
spin_unlock(&ctl->tree_lock);
2098
u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
2099
u64 offset, u64 bytes, u64 empty_size)
2101
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2102
struct btrfs_free_space *entry = NULL;
2103
u64 bytes_search = bytes + empty_size;
2106
spin_lock(&ctl->tree_lock);
2107
entry = find_free_space(ctl, &offset, &bytes_search);
2112
if (entry->bitmap) {
2113
bitmap_clear_bits(ctl, entry, offset, bytes);
2115
free_bitmap(ctl, entry);
2117
unlink_free_space(ctl, entry);
2118
entry->offset += bytes;
2119
entry->bytes -= bytes;
2121
kmem_cache_free(btrfs_free_space_cachep, entry);
2123
link_free_space(ctl, entry);
2127
spin_unlock(&ctl->tree_lock);
2133
* given a cluster, put all of its extents back into the free space
2134
* cache. If a block group is passed, this function will only free
2135
* a cluster that belongs to the passed block group.
2137
* Otherwise, it'll get a reference on the block group pointed to by the
2138
* cluster and remove the cluster from it.
2140
int btrfs_return_cluster_to_free_space(
2141
struct btrfs_block_group_cache *block_group,
2142
struct btrfs_free_cluster *cluster)
2144
struct btrfs_free_space_ctl *ctl;
2147
/* first, get a safe pointer to the block group */
2148
spin_lock(&cluster->lock);
2150
block_group = cluster->block_group;
2152
spin_unlock(&cluster->lock);
2155
} else if (cluster->block_group != block_group) {
2156
/* someone else has already freed it don't redo their work */
2157
spin_unlock(&cluster->lock);
2160
atomic_inc(&block_group->count);
2161
spin_unlock(&cluster->lock);
2163
ctl = block_group->free_space_ctl;
2165
/* now return any extents the cluster had on it */
2166
spin_lock(&ctl->tree_lock);
2167
ret = __btrfs_return_cluster_to_free_space(block_group, cluster);
2168
spin_unlock(&ctl->tree_lock);
2170
/* finally drop our ref */
2171
btrfs_put_block_group(block_group);
2175
static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group,
2176
struct btrfs_free_cluster *cluster,
2177
struct btrfs_free_space *entry,
2178
u64 bytes, u64 min_start)
2180
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2182
u64 search_start = cluster->window_start;
2183
u64 search_bytes = bytes;
2186
search_start = min_start;
2187
search_bytes = bytes;
2189
err = search_bitmap(ctl, entry, &search_start, &search_bytes);
2194
__bitmap_clear_bits(ctl, entry, ret, bytes);
2200
* given a cluster, try to allocate 'bytes' from it, returns 0
2201
* if it couldn't find anything suitably large, or a logical disk offset
2202
* if things worked out
2204
u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
2205
struct btrfs_free_cluster *cluster, u64 bytes,
2208
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2209
struct btrfs_free_space *entry = NULL;
2210
struct rb_node *node;
2213
spin_lock(&cluster->lock);
2214
if (bytes > cluster->max_size)
2217
if (cluster->block_group != block_group)
2220
node = rb_first(&cluster->root);
2224
entry = rb_entry(node, struct btrfs_free_space, offset_index);
2226
if (entry->bytes < bytes ||
2227
(!entry->bitmap && entry->offset < min_start)) {
2228
node = rb_next(&entry->offset_index);
2231
entry = rb_entry(node, struct btrfs_free_space,
2236
if (entry->bitmap) {
2237
ret = btrfs_alloc_from_bitmap(block_group,
2238
cluster, entry, bytes,
2241
node = rb_next(&entry->offset_index);
2244
entry = rb_entry(node, struct btrfs_free_space,
2249
ret = entry->offset;
2251
entry->offset += bytes;
2252
entry->bytes -= bytes;
2255
if (entry->bytes == 0)
2256
rb_erase(&entry->offset_index, &cluster->root);
2260
spin_unlock(&cluster->lock);
2265
spin_lock(&ctl->tree_lock);
2267
ctl->free_space -= bytes;
2268
if (entry->bytes == 0) {
2269
ctl->free_extents--;
2270
if (entry->bitmap) {
2271
kfree(entry->bitmap);
2272
ctl->total_bitmaps--;
2273
ctl->op->recalc_thresholds(ctl);
2275
kmem_cache_free(btrfs_free_space_cachep, entry);
2278
spin_unlock(&ctl->tree_lock);
2283
static int btrfs_bitmap_cluster(struct btrfs_block_group_cache *block_group,
2284
struct btrfs_free_space *entry,
2285
struct btrfs_free_cluster *cluster,
2286
u64 offset, u64 bytes, u64 min_bytes)
2288
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2289
unsigned long next_zero;
2291
unsigned long search_bits;
2292
unsigned long total_bits;
2293
unsigned long found_bits;
2294
unsigned long start = 0;
2295
unsigned long total_found = 0;
2299
i = offset_to_bit(entry->offset, block_group->sectorsize,
2300
max_t(u64, offset, entry->offset));
2301
search_bits = bytes_to_bits(bytes, block_group->sectorsize);
2302
total_bits = bytes_to_bits(min_bytes, block_group->sectorsize);
2306
for (i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i);
2307
i < BITS_PER_BITMAP;
2308
i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i + 1)) {
2309
next_zero = find_next_zero_bit(entry->bitmap,
2310
BITS_PER_BITMAP, i);
2311
if (next_zero - i >= search_bits) {
2312
found_bits = next_zero - i;
2323
cluster->max_size = 0;
2327
total_found += found_bits;
2329
if (cluster->max_size < found_bits * block_group->sectorsize)
2330
cluster->max_size = found_bits * block_group->sectorsize;
2332
if (total_found < total_bits) {
2333
i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, next_zero);
2334
if (i - start > total_bits * 2) {
2336
cluster->max_size = 0;
2342
cluster->window_start = start * block_group->sectorsize +
2344
rb_erase(&entry->offset_index, &ctl->free_space_offset);
2345
ret = tree_insert_offset(&cluster->root, entry->offset,
2346
&entry->offset_index, 1);
2353
* This searches the block group for just extents to fill the cluster with.
2356
setup_cluster_no_bitmap(struct btrfs_block_group_cache *block_group,
2357
struct btrfs_free_cluster *cluster,
2358
struct list_head *bitmaps, u64 offset, u64 bytes,
2361
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2362
struct btrfs_free_space *first = NULL;
2363
struct btrfs_free_space *entry = NULL;
2364
struct btrfs_free_space *prev = NULL;
2365
struct btrfs_free_space *last;
2366
struct rb_node *node;
2370
u64 max_gap = 128 * 1024;
2372
entry = tree_search_offset(ctl, offset, 0, 1);
2377
* We don't want bitmaps, so just move along until we find a normal
2380
while (entry->bitmap) {
2381
if (list_empty(&entry->list))
2382
list_add_tail(&entry->list, bitmaps);
2383
node = rb_next(&entry->offset_index);
2386
entry = rb_entry(node, struct btrfs_free_space, offset_index);
2389
window_start = entry->offset;
2390
window_free = entry->bytes;
2391
max_extent = entry->bytes;
2396
while (window_free <= min_bytes) {
2397
node = rb_next(&entry->offset_index);
2400
entry = rb_entry(node, struct btrfs_free_space, offset_index);
2402
if (entry->bitmap) {
2403
if (list_empty(&entry->list))
2404
list_add_tail(&entry->list, bitmaps);
2409
* we haven't filled the empty size and the window is
2410
* very large. reset and try again
2412
if (entry->offset - (prev->offset + prev->bytes) > max_gap ||
2413
entry->offset - window_start > (min_bytes * 2)) {
2415
window_start = entry->offset;
2416
window_free = entry->bytes;
2418
max_extent = entry->bytes;
2421
window_free += entry->bytes;
2422
if (entry->bytes > max_extent)
2423
max_extent = entry->bytes;
2428
cluster->window_start = first->offset;
2430
node = &first->offset_index;
2433
* now we've found our entries, pull them out of the free space
2434
* cache and put them into the cluster rbtree
2439
entry = rb_entry(node, struct btrfs_free_space, offset_index);
2440
node = rb_next(&entry->offset_index);
2444
rb_erase(&entry->offset_index, &ctl->free_space_offset);
2445
ret = tree_insert_offset(&cluster->root, entry->offset,
2446
&entry->offset_index, 0);
2448
} while (node && entry != last);
2450
cluster->max_size = max_extent;
2456
* This specifically looks for bitmaps that may work in the cluster, we assume
2457
* that we have already failed to find extents that will work.
2460
setup_cluster_bitmap(struct btrfs_block_group_cache *block_group,
2461
struct btrfs_free_cluster *cluster,
2462
struct list_head *bitmaps, u64 offset, u64 bytes,
2465
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2466
struct btrfs_free_space *entry;
2468
u64 bitmap_offset = offset_to_bitmap(ctl, offset);
2470
if (ctl->total_bitmaps == 0)
2474
* The bitmap that covers offset won't be in the list unless offset
2475
* is just its start offset.
2477
entry = list_first_entry(bitmaps, struct btrfs_free_space, list);
2478
if (entry->offset != bitmap_offset) {
2479
entry = tree_search_offset(ctl, bitmap_offset, 1, 0);
2480
if (entry && list_empty(&entry->list))
2481
list_add(&entry->list, bitmaps);
2484
list_for_each_entry(entry, bitmaps, list) {
2485
if (entry->bytes < min_bytes)
2487
ret = btrfs_bitmap_cluster(block_group, entry, cluster, offset,
2494
* The bitmaps list has all the bitmaps that record free space
2495
* starting after offset, so no more search is required.
2501
* here we try to find a cluster of blocks in a block group. The goal
2502
* is to find at least bytes free and up to empty_size + bytes free.
2503
* We might not find them all in one contiguous area.
2505
* returns zero and sets up cluster if things worked out, otherwise
2506
* it returns -enospc
2508
int btrfs_find_space_cluster(struct btrfs_trans_handle *trans,
2509
struct btrfs_root *root,
2510
struct btrfs_block_group_cache *block_group,
2511
struct btrfs_free_cluster *cluster,
2512
u64 offset, u64 bytes, u64 empty_size)
2514
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2515
struct btrfs_free_space *entry, *tmp;
2520
/* for metadata, allow allocates with more holes */
2521
if (btrfs_test_opt(root, SSD_SPREAD)) {
2522
min_bytes = bytes + empty_size;
2523
} else if (block_group->flags & BTRFS_BLOCK_GROUP_METADATA) {
2525
* we want to do larger allocations when we are
2526
* flushing out the delayed refs, it helps prevent
2527
* making more work as we go along.
2529
if (trans->transaction->delayed_refs.flushing)
2530
min_bytes = max(bytes, (bytes + empty_size) >> 1);
2532
min_bytes = max(bytes, (bytes + empty_size) >> 4);
2534
min_bytes = max(bytes, (bytes + empty_size) >> 2);
2536
spin_lock(&ctl->tree_lock);
2539
* If we know we don't have enough space to make a cluster don't even
2540
* bother doing all the work to try and find one.
2542
if (ctl->free_space < min_bytes) {
2543
spin_unlock(&ctl->tree_lock);
2547
spin_lock(&cluster->lock);
2549
/* someone already found a cluster, hooray */
2550
if (cluster->block_group) {
2555
ret = setup_cluster_no_bitmap(block_group, cluster, &bitmaps, offset,
2558
ret = setup_cluster_bitmap(block_group, cluster, &bitmaps,
2559
offset, bytes, min_bytes);
2561
/* Clear our temporary list */
2562
list_for_each_entry_safe(entry, tmp, &bitmaps, list)
2563
list_del_init(&entry->list);
2566
atomic_inc(&block_group->count);
2567
list_add_tail(&cluster->block_group_list,
2568
&block_group->cluster_list);
2569
cluster->block_group = block_group;
2572
spin_unlock(&cluster->lock);
2573
spin_unlock(&ctl->tree_lock);
2579
* simple code to zero out a cluster
2581
void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster)
2583
spin_lock_init(&cluster->lock);
2584
spin_lock_init(&cluster->refill_lock);
2585
cluster->root = RB_ROOT;
2586
cluster->max_size = 0;
2587
INIT_LIST_HEAD(&cluster->block_group_list);
2588
cluster->block_group = NULL;
2591
int btrfs_trim_block_group(struct btrfs_block_group_cache *block_group,
2592
u64 *trimmed, u64 start, u64 end, u64 minlen)
2594
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
2595
struct btrfs_free_space *entry = NULL;
2596
struct btrfs_fs_info *fs_info = block_group->fs_info;
2598
u64 actually_trimmed;
2603
while (start < end) {
2604
spin_lock(&ctl->tree_lock);
2606
if (ctl->free_space < minlen) {
2607
spin_unlock(&ctl->tree_lock);
2611
entry = tree_search_offset(ctl, start, 0, 1);
2613
entry = tree_search_offset(ctl,
2614
offset_to_bitmap(ctl, start),
2617
if (!entry || entry->offset >= end) {
2618
spin_unlock(&ctl->tree_lock);
2622
if (entry->bitmap) {
2623
ret = search_bitmap(ctl, entry, &start, &bytes);
2626
spin_unlock(&ctl->tree_lock);
2629
bytes = min(bytes, end - start);
2630
bitmap_clear_bits(ctl, entry, start, bytes);
2631
if (entry->bytes == 0)
2632
free_bitmap(ctl, entry);
2634
start = entry->offset + BITS_PER_BITMAP *
2635
block_group->sectorsize;
2636
spin_unlock(&ctl->tree_lock);
2641
start = entry->offset;
2642
bytes = min(entry->bytes, end - start);
2643
unlink_free_space(ctl, entry);
2644
kmem_cache_free(btrfs_free_space_cachep, entry);
2647
spin_unlock(&ctl->tree_lock);
2649
if (bytes >= minlen) {
2650
struct btrfs_space_info *space_info;
2653
space_info = block_group->space_info;
2654
spin_lock(&space_info->lock);
2655
spin_lock(&block_group->lock);
2656
if (!block_group->ro) {
2657
block_group->reserved += bytes;
2658
space_info->bytes_reserved += bytes;
2661
spin_unlock(&block_group->lock);
2662
spin_unlock(&space_info->lock);
2664
ret = btrfs_error_discard_extent(fs_info->extent_root,
2669
btrfs_add_free_space(block_group, start, bytes);
2671
spin_lock(&space_info->lock);
2672
spin_lock(&block_group->lock);
2673
if (block_group->ro)
2674
space_info->bytes_readonly += bytes;
2675
block_group->reserved -= bytes;
2676
space_info->bytes_reserved -= bytes;
2677
spin_unlock(&space_info->lock);
2678
spin_unlock(&block_group->lock);
2683
*trimmed += actually_trimmed;
2688
if (fatal_signal_pending(current)) {
2700
* Find the left-most item in the cache tree, and then return the
2701
* smallest inode number in the item.
2703
* Note: the returned inode number may not be the smallest one in
2704
* the tree, if the left-most item is a bitmap.
2706
u64 btrfs_find_ino_for_alloc(struct btrfs_root *fs_root)
2708
struct btrfs_free_space_ctl *ctl = fs_root->free_ino_ctl;
2709
struct btrfs_free_space *entry = NULL;
2712
spin_lock(&ctl->tree_lock);
2714
if (RB_EMPTY_ROOT(&ctl->free_space_offset))
2717
entry = rb_entry(rb_first(&ctl->free_space_offset),
2718
struct btrfs_free_space, offset_index);
2720
if (!entry->bitmap) {
2721
ino = entry->offset;
2723
unlink_free_space(ctl, entry);
2727
kmem_cache_free(btrfs_free_space_cachep, entry);
2729
link_free_space(ctl, entry);
2735
ret = search_bitmap(ctl, entry, &offset, &count);
2739
bitmap_clear_bits(ctl, entry, offset, 1);
2740
if (entry->bytes == 0)
2741
free_bitmap(ctl, entry);
2744
spin_unlock(&ctl->tree_lock);
2749
struct inode *lookup_free_ino_inode(struct btrfs_root *root,
2750
struct btrfs_path *path)
2752
struct inode *inode = NULL;
2754
spin_lock(&root->cache_lock);
2755
if (root->cache_inode)
2756
inode = igrab(root->cache_inode);
2757
spin_unlock(&root->cache_lock);
2761
inode = __lookup_free_space_inode(root, path, 0);
2765
spin_lock(&root->cache_lock);
2766
if (!btrfs_fs_closing(root->fs_info))
2767
root->cache_inode = igrab(inode);
2768
spin_unlock(&root->cache_lock);
2773
int create_free_ino_inode(struct btrfs_root *root,
2774
struct btrfs_trans_handle *trans,
2775
struct btrfs_path *path)
2777
return __create_free_space_inode(root, trans, path,
2778
BTRFS_FREE_INO_OBJECTID, 0);
2781
int load_free_ino_cache(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
2783
struct btrfs_free_space_ctl *ctl = root->free_ino_ctl;
2784
struct btrfs_path *path;
2785
struct inode *inode;
2787
u64 root_gen = btrfs_root_generation(&root->root_item);
2789
if (!btrfs_test_opt(root, INODE_MAP_CACHE))
2793
* If we're unmounting then just return, since this does a search on the
2794
* normal root and not the commit root and we could deadlock.
2796
if (btrfs_fs_closing(fs_info))
2799
path = btrfs_alloc_path();
2803
inode = lookup_free_ino_inode(root, path);
2807
if (root_gen != BTRFS_I(inode)->generation)
2810
ret = __load_free_space_cache(root, inode, ctl, path, 0);
2813
printk(KERN_ERR "btrfs: failed to load free ino cache for "
2814
"root %llu\n", root->root_key.objectid);
2818
btrfs_free_path(path);
2822
int btrfs_write_out_ino_cache(struct btrfs_root *root,
2823
struct btrfs_trans_handle *trans,
2824
struct btrfs_path *path)
2826
struct btrfs_free_space_ctl *ctl = root->free_ino_ctl;
2827
struct inode *inode;
2830
if (!btrfs_test_opt(root, INODE_MAP_CACHE))
2833
inode = lookup_free_ino_inode(root, path);
2837
ret = __btrfs_write_out_cache(root, inode, ctl, NULL, trans, path, 0);
2839
btrfs_delalloc_release_metadata(inode, inode->i_size);
2841
printk(KERN_ERR "btrfs: failed to write free ino cache "
2842
"for root %llu\n", root->root_key.objectid);