This patch adds the following helper structure and routines into
badblocks.h,
- struct bad_context
  This structure is used in improved badblocks code for bad table
  iteration.
- BB_END()
  The macro to culculate end LBA of a bad range record from bad
  table.
- badblocks_full() and badblocks_empty()
  The inline routines to check whether bad table is full or empty.
- set_changed() and clear_changed()
  The inline routines to set and clear 'changed' tag from struct
  badblocks.

These new helper structure and routines can help to make the code more
clear, they will be used in the improved badblocks code in following
patches.

Signed-off-by: Coly Li <redacted>
---
 include/linux/badblocks.h | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/include/linux/badblocks.h b/include/linux/badblocks.h
index 2426276b9bd3..166161842d1f 100644
--- a/include/linux/badblocks.h
+++ b/include/linux/badblocks.h

@@ -15,6 +15,7 @@
 #define BB_OFFSET(x)	(((x) & BB_OFFSET_MASK) >> 9)
 #define BB_LEN(x)	(((x) & BB_LEN_MASK) + 1)
 #define BB_ACK(x)	(!!((x) & BB_ACK_MASK))
+#define BB_END(x)	(BB_OFFSET(x) + BB_LEN(x))
 #define BB_MAKE(a, l, ack) (((a)<<9) | ((l)-1) | ((u64)(!!(ack)) << 63))
 
 /* Bad block numbers are stored sorted in a single page.

@@ -41,6 +42,14 @@ struct badblocks {
 	sector_t size;		/* in sectors */
 };
 
+struct bad_context {
+	sector_t	start;
+	sector_t	len;
+	int		ack;
+	sector_t	orig_start;
+	sector_t	orig_len;
+};
+