ocfs2: New slot map format
The old slot map had a few limitations:
- It was limited to one block, so the maximum slot count was 255.
- Each slot was signed 16bits, limiting node numbers to INT16_MAX.
- An empty slot was marked by the magic 0xFFFF (-1).
The new slot map format provides 32bit node numbers (UINT32_MAX), a
separate space to mark a slot in use, and extra room to grow. The slot
map is now bounded by i_size, not a block.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 95f783d..f78e9ed 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -374,6 +374,13 @@
return (osb->s_feature_incompat & OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT);
}
+static inline int ocfs2_uses_extended_slot_map(struct ocfs2_super *osb)
+{
+ return (osb->s_feature_incompat &
+ OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP);
+}
+
+
#define OCFS2_IS_VALID_DINODE(ptr) \
(!strcmp((ptr)->i_signature, OCFS2_INODE_SIGNATURE))