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;
+}
diff --git a/fs/nilfs2/bmap.h b/fs/nilfs2/bmap.h
index a20569b..5f3339e 100644
--- a/fs/nilfs2/bmap.h
+++ b/fs/nilfs2/bmap.h
@@ -135,6 +135,12 @@
/* state */
#define NILFS_BMAP_DIRTY 0x00000001
+struct nilfs_bmap_store {
+ __le64 data[NILFS_BMAP_SIZE / sizeof(__le64)];
+ __u64 last_allocated_key;
+ __u64 last_allocated_ptr;
+ int state;
+};
int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *);
int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);
@@ -156,6 +162,8 @@
void nilfs_bmap_init_gcdat(struct nilfs_bmap *, struct nilfs_bmap *);
void nilfs_bmap_commit_gcdat(struct nilfs_bmap *, struct nilfs_bmap *);
+void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *);
+void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *);
static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key,
__u64 *ptr)