[PATCH] libxfs: don't return cnt as failure from XFS_BUF_SET_PTR

[Eric Sandeen <sandeen@redhat.com>]

We must not get here very often, because any test of an error
from XFS_BUF_SET_PTR will fail because it  returns whatever
is sent in as cnt.  Fix the macro to return 0 so that
"error = XFS_BUF_SET_PTR()" works as expected.

Should probably make this xfs_buf_associate_memory() to be
more like kernelspace, but for now just fix up the bug.

Found this via xfs_logprint failing for no good reason.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h
index 81d2804..0ae7a28 100644
--- a/libxfs/libxfs_io.h
+++ b/libxfs/libxfs_io.h
@@ -105,6 +105,7 @@ enum xfs_buf_flags_t {	/* b_flags bits */
 #define XFS_BUF_SET_PTR(bp,p,cnt)	({	\
 	(bp)->b_addr = (char *)(p);		\
 	XFS_BUF_SET_COUNT(bp,cnt);		\
+	0;					\
 })
 
 #define XFS_BUF_SET_ADDR(bp,blk)	((bp)->b_bn = (blk))