/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/crc32c.h>
#include <linux/scatterlist.h>
#include <linux/swap.h>
#include <linux/radix-tree.h>
#include <linux/writeback.h>
#include <linux/buffer_head.h> // for block_sync_page
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.h"
#if 0
static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
{
if (extent_buffer_blocknr(buf) != btrfs_header_blocknr(buf)) {
printk(KERN_CRIT "buf blocknr(buf) is %llu, header is %llu\n",
(unsigned long long)extent_buffer_blocknr(buf),
(unsigned long long)btrfs_header_blocknr(buf));
return 1;
}
return 0;
}
#endif
struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
u64 blocknr)
{
struct inode *btree_inode = root->fs_info->btree_inode;
struct extent_buffer *eb;
eb = find_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
blocknr * root->sectorsize,
root->sectorsize, GFP_NOFS);
if (eb)
eb->alloc_addr = (unsigned long)__builtin_return_address(0);
return eb;
}
struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
u64 blocknr)
{
struct inode *btree_inode = root->fs_info->btree_inode;
struct extent_buffer *eb;
eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
blocknr * root->sectorsize,
root->sectorsize, GFP_NOFS);
eb->alloc_addr = (unsigned long)__builtin_return_address(0);
return eb;
}
struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
size_t page_offset, u64 start, u64 end,
int create)
{
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
struct extent_map *em;
int ret;
again:
em = lookup_extent_mapping(em_tree, start, end);
if (em) {
goto out;
}
em = alloc_extent_map(GFP_NOFS);
if (!em) {
em = ERR_PTR(-ENOMEM);
goto out;
}
em->start = 0;
em->end = (i_size_read(inode) & ~((u64)PAGE_CACHE_SIZE -1)) - 1;
em->block_start = 0;
em->block_end = em->end;
em->bdev = inode->i_sb->s_bdev;
ret = add_extent_mapping(em_tree, em);
if (ret == -EEXIST) {
free_extent_map(em);
em = NULL;
goto again;
} else if (ret) {
em = ERR_PTR(ret);
}
out:
return em;
}
static int btree_writepage(struct page *page, struct writeback_control *wbc)
{
struct extent_map_tree *tree;
tree = &BTRFS_I(page->mapping->host)->extent_tree;
return extent_write_full_page(tree, page, btree_get_extent, wbc);
}
int btree_readpage(struct file *file, struct page *page)
{
struct extent_map_tree *tree;
tree = &BTRFS_I(page->mapping->host)->extent_tree;
return extent_read_full_page(tree, page, btree_get_extent);
}
static int btree_releasepage(struct page *page, gfp_t unused_gfp_flags)
{
struct extent_map_tree *tree;
int ret;
BUG_ON(page->private != 1);
tree = &BTRFS_I(page->mapping->host)->extent_tree;
ret = try_release_extent_mapping(tree, page);
if (ret == 1) {
ClearPagePrivate(page);
set_page_private(page, 0);
page_cache_release(page);
}
return ret;
}
static void btree_invalidatepage(struct page *page, unsigned long offset)
{
struct extent_map_tree *tree;
tree = &BTRFS_I(page->mapping->host)->extent_tree;
extent_invalidatepage(tree, page, offset);
btree_releasepage(page, GFP_NOFS);
}
int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
char *result)
{
return 0;
#if 0
u32 crc;
crc = crc32c(0, data, len);
memcpy(result, &crc, BTRFS_CRC32_SIZE);
return 0;
#endif
}
#if 0
static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
int verify)
{
return 0;
char result[BTRFS_CRC32_SIZE];
int ret;
struct btrfs_node *node;
ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
bh->b_size - BTRFS_CSUM_SIZE, result);
if (ret)
return ret;
if (verify) {
if (memcmp(bh->b_data, result, BTRFS_CRC32_SIZE)) {
printk("btrfs: %s checksum verify failed on %llu\n",
root->fs_info->sb->s_id,
(unsigned long long)bh_blocknr(bh));
return 1;
}
} else {
node = btrfs_buffer_node(bh);
memcpy(node->header.csum, result, BTRFS_CRC32_SIZE);
}
return 0;
}
#endif
#if 0
static int btree_writepage(struct page *page, struct writeback_control *wbc)
{
struct buffer_head *bh;
struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
struct buffer_head *head;
if (!page_has_buffers(page)) {
create_empty_buffers(page, root->fs_info->sb->s_blocksize,
(1 << BH_Dirty)|(1 << BH_Uptodate));
}
head = page_buffers(page);
bh = head;
do {
if (buffer_dirty(bh))
csum_tree_block(root, bh, 0);
bh = bh->b_this_page;
} while (bh != head);
return block_write_full_page(page, btree_get_block, wbc);
}
#endif
static struct address_space_operations btree_aops = {
.readpage = btree_readpage,
.writepage = btree_writepage,
.releasepage = btree_releasepage,
.invalidatepage = btree_invalidatepage,
.sync_page = block_sync_page,
};
int readahead_tree_block(struct btrfs_root *root, u64 blocknr)
{
struct extent_buffer *buf = NULL;
struct inode *btree_inode = root->fs_info->btree_inode;
int ret = 0;
buf = btrfs_find_create_tree_block(root, blocknr);
if (!buf)
return 0;
read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
buf, 0);
free_extent_buffer(buf);
return ret;
}
struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
{
struct extent_buffer *buf = NULL;
struct inode *btree_inode = root->fs_info->btree_inode;
buf = btrfs_find_create_tree_block(root, blocknr);
if (!buf)
return NULL;
read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
buf, 1);
buf->alloc_addr = (unsigned long)__builtin_return_address(0);
return buf;
}
int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf)
{
struct inode *btree_inode = root->fs_info->btree_inode;
clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
return 0;
}
int wait_on_tree_block_writeback(struct btrfs_root *root,
struct extent_buffer *buf)
{
struct inode *btree_inode = root->fs_info->btree_inode;
wait_on_extent_buffer_writeback(&BTRFS_I(btree_inode)->extent_tree,
buf);
return 0;
}
int set_tree_block_dirty(struct btrfs_root *root, struct extent_buffer *buf)
{
struct inode *btree_inode = root->fs_info->btree_inode;
set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
return 0;
}
static int __setup_root(int blocksize,
struct btrfs_root *root,
struct btrfs_fs_info *fs_info,
u64 objectid)
{
root->node = NULL;
root->inode = NULL;
root->commit_root = NULL;
root->sectorsize = blocksize;
root->nodesize = blocksize;
root->leafsize = blocksize;
root->ref_cows = 0;
root->fs_info = fs_info;
root->objectid = objectid;
root->last_trans = 0;
root->highest_inode = 0;
root->last_inode_alloc = 0;
root->name = NULL;
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
memset(&root->root_kobj, 0, sizeof(root->root_kobj));
init_completion(&root->kobj_unregister);
init_rwsem(&root->snap_sem);
root->defrag_running = 0;
root->defrag_level = 0;
root->root_key.objectid = objectid;
return 0;
}
static int find_and_setup_root(int blocksize,
struct btrfs_root *tree_root,
struct btrfs_fs_info *fs_info,
u64 objectid,
struct btrfs_root *root)
{
int ret;
__setup_root(blocksize, root, fs_info, objectid);
ret = btrfs_find_last_root(tree_root, objectid,
&root->root_item, &root->root_key);
BUG_ON(ret);
root->node = read_tree_block(root,
btrfs_root_blocknr(&root->root_item));
BUG_ON(!root->node);
return 0;
}
struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
struct btrfs_key *location)
{
struct btrfs_root *root;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_path *path;
struct extent_buffer *l;
u64 highest_inode;
int ret = 0;
root = kzalloc(sizeof(*root), GFP_NOFS);
if (!root)
return ERR_PTR(-ENOMEM);
if (location->offset == (u64)-1) {
ret = find_and_setup_root(fs_info->sb->s_blocksize,
fs_info->tree_root, fs_info,
location->objectid, root);
if (ret) {
kfree(root);
return ERR_PTR(ret);
}
goto insert;
}
__setup_root(fs_info->sb->s_blocksize, root, fs_info,
location->objectid);
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
if (ret != 0) {
if (ret > 0)
ret = -ENOENT;
goto out;
}
l = path->nodes[0];
read_extent_buffer(l, &root->root_item,
btrfs_item_ptr_offset(l, path->slots[0]),
sizeof(root->root_item));
ret = 0;
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
if (ret) {
kfree(root);
return ERR_PTR(ret);
}
root->node = read_tree_block(root,
btrfs_root_blocknr(&root->root_item));
BUG_ON(!root->node);
insert:
root->ref_cows = 1;
ret = btrfs_find_highest_inode(root, &highest_inode);
if (ret == 0) {
root->highest_inode = highest_inode;
root->last_inode_alloc = highest_inode;
}
return root;
}
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
struct btrfs_key *location,
const char *name, int namelen)
{
struct btrfs_root *root;
int ret;
root = radix_tree_lookup(&fs_info->fs_roots_radix,
(unsigned long)location->objectid);
if (root)
return root;
root = btrfs_read_fs_root_no_radix(fs_info, location);
if (IS_ERR(root))
return root;
ret = radix_tree_insert(&fs_info->fs_roots_radix,
(unsigned long)root->root_key.objectid,
root);
if (ret) {
free_extent_buffer(root->node);
kfree(root);
return ERR_PTR(ret);
}
ret = btrfs_set_root_name(root, name, namelen);
if (ret) {
free_extent_buffer(root->node);
kfree(root);
return ERR_PTR(ret);
}
ret = btrfs_sysfs_add_root(root);
if (ret) {
free_extent_buffer(root->node);
kfree(root->name);
kfree(root);
return ERR_PTR(ret);
}
ret = btrfs_find_dead_roots(fs_info->tree_root,
root->root_key.objectid, root);
BUG_ON(ret);
return root;
}
struct btrfs_root *open_ctree(struct super_block *sb)
{
struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
GFP_NOFS);
struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
GFP_NOFS);
struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
GFP_NOFS);
int ret;
int err = -EIO;
struct btrfs_super_block *disk_super;
if (!extent_root || !tree_root || !fs_info) {
err = -ENOMEM;
goto fail;
}
INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
INIT_LIST_HEAD(&fs_info->trans_list);
INIT_LIST_HEAD(&fs_info->dead_roots);
memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
init_completion(&fs_info->kobj_unregister);
sb_set_blocksize(sb, 4096);
fs_info->running_transaction = NULL;
fs_info->last_trans_committed = 0;
fs_info->tree_root = tree_root;
fs_info->extent_root = extent_root;
fs_info->sb = sb;
fs_info->btree_inode = new_inode(sb);
fs_info->btree_inode->i_ino = 1;
fs_info->btree_inode->i_nlink = 1;
fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
fs_info->btree_inode->i_mapping,
GFP_NOFS);
extent_map_tree_init(&fs_info->free_space_cache,
fs_info->btree_inode->i_mapping, GFP_NOFS);
extent_map_tree_init(&fs_info->block_group_cache,
fs_info->btree_inode->i_mapping, GFP_NOFS);
extent_map_tree_init(&fs_info->pinned_extents,
fs_info->btree_inode->i_mapping, GFP_NOFS);
extent_map_tree_init(&fs_info->pending_del,
fs_info->btree_inode->i_mapping, GFP_NOFS);
extent_map_tree_init(&fs_info->extent_ins,
fs_info->btree_inode->i_mapping, GFP_NOFS);
fs_info->do_barriers = 1;
fs_info->closing = 0;
INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
BTRFS_I(fs_info->btree_inode)->root = tree_root;
memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
sizeof(struct btrfs_key));
insert_inode_hash(fs_info->btree_inode);
mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
mutex_init(&fs_info->trans_mutex);
mutex_init(&fs_info->fs_mutex);
__setup_root(sb->s_blocksize, tree_root,
fs_info, BTRFS_ROOT_TREE_OBJECTID);
fs_info->sb_buffer = read_tree_block(tree_root,
BTRFS_SUPER_INFO_OFFSET /
sb->s_blocksize);
if (!fs_info->sb_buffer)
goto fail_iput;
read_extent_buffer(fs_info->sb_buffer, &fs_info->super_copy, 0,
sizeof(fs_info->super_copy));
read_extent_buffer(fs_info->sb_buffer, fs_info->fsid,
(unsigned long)btrfs_super_fsid(fs_info->sb_buffer),
BTRFS_FSID_SIZE);
disk_super = &fs_info->super_copy;
if (!btrfs_super_root(disk_super))
goto fail_sb_buffer;
i_size_write(fs_info->btree_inode,
btrfs_super_total_blocks(disk_super) <<
fs_info->btree_inode->i_blkbits);
if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
sizeof(disk_super->magic))) {
printk("btrfs: valid FS not found on %s\n", sb->s_id);
goto fail_sb_buffer;
}
tree_root->node = read_tree_block(tree_root,
btrfs_super_root(disk_super));
if (!tree_root->node)
goto fail_sb_buffer;
mutex_lock(&fs_info->fs_mutex);
ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
BTRFS_EXTENT_TREE_OBJECTID, extent_root);
if (ret) {
mutex_unlock(&fs_info->fs_mutex);
goto fail_tree_root;
}
btrfs_read_block_groups(extent_root);
fs_info->generation = btrfs_super_generation(disk_super) + 1;
mutex_unlock(&fs_info->fs_mutex);
return tree_root;
fail_tree_root:
free_extent_buffer(tree_root->node);
fail_sb_buffer:
free_extent_buffer(fs_info->sb_buffer);
fail_iput:
iput(fs_info->btree_inode);
fail:
kfree(extent_root);
kfree(tree_root);
kfree(fs_info);
return ERR_PTR(err);
}
int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
*root)
{
int ret;
struct extent_buffer *super = root->fs_info->sb_buffer;
struct inode *btree_inode = root->fs_info->btree_inode;
set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, super);
ret = sync_page_range_nolock(btree_inode, btree_inode->i_mapping,
super->start, super->len);
return ret;
}
int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
{
radix_tree_delete(&fs_info->fs_roots_radix,
(unsigned long)root->root_key.objectid);
btrfs_sysfs_del_root(root);
if (root->inode)
iput(root->inode);
if (root->node)
free_extent_buffer(root->node);
if (root->commit_root)
free_extent_buffer(root->commit_root);
if (root->name)
kfree(root->name);
kfree(root);
return 0;
}
static int del_fs_roots(struct btrfs_fs_info *fs_info)
{
int ret;
struct btrfs_root *gang[8];
int i;
while(1) {
ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
(void **)gang, 0,
ARRAY_SIZE(gang));
if (!ret)
break;
for (i = 0; i < ret; i++)
btrfs_free_fs_root(fs_info, gang[i]);
}
return 0;
}
int close_ctree(struct btrfs_root *root)
{
int ret;
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *fs_info = root->fs_info;
fs_info->closing = 1;
btrfs_transaction_flush_work(root);
mutex_lock(&fs_info->fs_mutex);
btrfs_defrag_dirty_roots(root->fs_info);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
/* run commit again to drop the original snapshot */
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
ret = btrfs_write_and_wait_transaction(NULL, root);
BUG_ON(ret);
write_ctree_super(NULL, root);
mutex_unlock(&fs_info->fs_mutex);
if (fs_info->extent_root->node)
free_extent_buffer(fs_info->extent_root->node);
if (fs_info->tree_root->node)
free_extent_buffer(fs_info->tree_root->node);
free_extent_buffer(fs_info->sb_buffer);
truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
iput(fs_info->btree_inode);
btrfs_free_block_groups(root->fs_info);
del_fs_roots(fs_info);
kfree(fs_info->extent_root);
kfree(fs_info->tree_root);
return 0;
}
int btrfs_buffer_uptodate(struct extent_buffer *buf)
{
struct inode *btree_inode = buf->first_page->mapping->host;
return extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree, buf);
}
int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
{
struct inode *btree_inode = buf->first_page->mapping->host;
return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree,
buf);
}
void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
{
struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
u64 transid = btrfs_header_generation(buf);
struct inode *btree_inode = root->fs_info->btree_inode;
if (transid != root->fs_info->generation) {
printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
(unsigned long long)extent_buffer_blocknr(buf),
transid, root->fs_info->generation);
WARN_ON(1);
}
set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
}
void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
{
balance_dirty_pages_ratelimited_nr(
root->fs_info->btree_inode->i_mapping, nr);
}
