static int __commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
u64 start;
u64 end;
struct extent_buffer *eb;
struct extent_io_tree *tree = &root->fs_info->extent_cache;
int ret;
while(1) {
ret = find_first_extent_bit(tree, 0, &start, &end,
EXTENT_DIRTY);
if (ret)
break;
while(start <= end) {
eb = find_first_extent_buffer(tree, start);
BUG_ON(!eb || eb->start != start);
ret = write_tree_block(trans, root, eb);
BUG_ON(ret);
start += eb->len;
clear_extent_buffer_dirty(eb);
free_extent_buffer(eb);
}
}
return 0;
}
static int custom_alloc_extent(struct btrfs_root *root, u64 num_bytes,
u64 hint_byte, struct btrfs_key *ins)
{
u64 start;
u64 end;
u64 last = hint_byte;
int ret;
int wrapped = 0;
struct btrfs_block_group_cache *cache;
while (1) {
ret = find_first_extent_bit(&root->fs_info->free_space_cache,
last, &start, &end, EXTENT_DIRTY);
if (ret) {
if (wrapped++ == 0) {
last = 0;
continue;
} else {
goto fail;
}
}
start = max(last, start);
last = end + 1;
if (last - start < num_bytes)
continue;
last = start + num_bytes;
if (test_range_bit(&root->fs_info->pinned_extents,
start, last - 1, EXTENT_DIRTY, 0))
continue;
cache = btrfs_lookup_block_group(root->fs_info, start);
BUG_ON(!cache);
if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM ||
last > cache->key.objectid + cache->key.offset) {
last = cache->key.objectid + cache->key.offset;
continue;
}
if (cache->flags & (BTRFS_BLOCK_GROUP_SYSTEM |
BTRFS_BLOCK_GROUP_METADATA)) {
last = cache->key.objectid + cache->key.offset;
continue;
}
clear_extent_dirty(&root->fs_info->free_space_cache,
start, start + num_bytes - 1, 0);
ins->objectid = start;
ins->offset = num_bytes;
ins->type = BTRFS_EXTENT_ITEM_KEY;
return 0;
}
fail:
fprintf(stderr, "not enough free space\n");
return -ENOSPC;
}
int btrfs_write_marked_extents(struct btrfs_root *root,
struct extent_io_tree *dirty_pages, int mark)
{
int ret;
int err = 0;
int werr = 0;
struct page *page;
struct inode *btree_inode = root->fs_info->btree_inode;
u64 start = 0;
u64 end;
unsigned long index;
while (1) {
ret = find_first_extent_bit(dirty_pages, start, &start, &end,
mark);
if (ret)
break;
while (start <= end) {
cond_resched();
index = start >> PAGE_CACHE_SHIFT;
start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
page = find_get_page(btree_inode->i_mapping, index);
if (!page)
continue;
btree_lock_page_hook(page);
if (!page->mapping) {
unlock_page(page);
page_cache_release(page);
continue;
}
if (PageWriteback(page)) {
if (PageDirty(page))
wait_on_page_writeback(page);
else {
unlock_page(page);
page_cache_release(page);
continue;
}
}
err = write_one_page(page, 0);
if (err)
werr = err;
page_cache_release(page);
}
}
if (err)
werr = err;
return werr;
}