xfs: split freemap from xchk_xattr_buf.buf

Move the free space bitmap from somewhere in xchk_xattr_buf.buf[] to an
explicit pointer.  This is the start of removing the complex overloaded
memory buffer that is the source of weird memory misuse bugs.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

1 files changed, 4 insertions, 11 deletions

diff --git a/fs/xfs/scrub/attr.h b/fs/xfs/scrub/attr.h
index daf354a581bb..341855b3201b 100644
--- a/fs/xfs/scrub/attr.h
+++ b/fs/xfs/scrub/attr.h
@@ -10,6 +10,9 @@
  * Temporary storage for online scrub and repair of extended attributes.
  */
 struct xchk_xattr_buf {
+	/* Bitmap of free space in xattr leaf blocks. */
+	unsigned long		*freemap;
+
 	/* Size of @buf, in bytes. */
 	size_t			sz;
 
@@ -20,8 +23,7 @@ struct xchk_xattr_buf {
 	 *
 	 * Each bitmap contains enough bits to track every byte in an attr
 	 * block (rounded up to the size of an unsigned long).  The attr block
-	 * used space bitmap starts at the beginning of the buffer; the free
-	 * space bitmap follows immediately after.
+	 * used space bitmap starts at the beginning of the buffer.
 	 */
 	uint8_t			buf[];
 };
@@ -46,13 +48,4 @@ xchk_xattr_usedmap(
 	return (unsigned long *)ab->buf;
 }
 
-/* A bitmap of free space computed by walking attr leaf block free info. */
-static inline unsigned long *
-xchk_xattr_freemap(
-	struct xfs_scrub	*sc)
-{
-	return xchk_xattr_usedmap(sc) +
-			BITS_TO_LONGS(sc->mp->m_attr_geo->blksize);
-}
-
 #endif	/* __XFS_SCRUB_ATTR_H__ */