nilfs2: add routines to save and restore bmap state
This adds routines to save and restore the state of bmap structure.
The bmap state is stored in a given nilfs_bmap_store object.
These routines will be used to roll back the state of dat inode
without using gcdat inode.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/bmap.c b/fs/nilfs2/bmap.c
index 3dbdc1d..0024440 100644
--- a/fs/nilfs2/bmap.c
+++ b/fs/nilfs2/bmap.c
@@ -548,3 +548,21 @@
lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
}
+
+void nilfs_bmap_save(const struct nilfs_bmap *bmap,
+ struct nilfs_bmap_store *store)
+{
+ memcpy(store->data, bmap->b_u.u_data, sizeof(store->data));
+ store->last_allocated_key = bmap->b_last_allocated_key;
+ store->last_allocated_ptr = bmap->b_last_allocated_ptr;
+ store->state = bmap->b_state;
+}
+
+void nilfs_bmap_restore(struct nilfs_bmap *bmap,
+ const struct nilfs_bmap_store *store)
+{
+ memcpy(bmap->b_u.u_data, store->data, sizeof(store->data));
+ bmap->b_last_allocated_key = store->last_allocated_key;
+ bmap->b_last_allocated_ptr = store->last_allocated_ptr;
+ bmap->b_state = store->state;
+}