Btrfs: check for a null fs root when writing to the backup root log

During log replay, can commit the transaction before the fs_root
pointers are setup, so we have to make sure they are not null before
trying to use them.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2011-11-06 18:50:56 -05:00
parent d43317dcd0
commit 7c7e82a77f

View File

@ -1754,11 +1754,18 @@ static void backup_super_roots(struct btrfs_fs_info *info)
btrfs_set_backup_extent_root_level(root_backup,
btrfs_header_level(info->extent_root->node));
btrfs_set_backup_fs_root(root_backup, info->fs_root->node->start);
btrfs_set_backup_fs_root_gen(root_backup,
/*
* we might commit during log recovery, which happens before we set
* the fs_root. Make sure it is valid before we fill it in.
*/
if (info->fs_root && info->fs_root->node) {
btrfs_set_backup_fs_root(root_backup,
info->fs_root->node->start);
btrfs_set_backup_fs_root_gen(root_backup,
btrfs_header_generation(info->fs_root->node));
btrfs_set_backup_fs_root_level(root_backup,
btrfs_set_backup_fs_root_level(root_backup,
btrfs_header_level(info->fs_root->node));
}
btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
btrfs_set_backup_dev_root_gen(root_backup,