[XFS] Make buffer error checking consistent, add a value range check.

SGI Modid: xfs-linux:xfs-kern:169542a

fs/xfs/linux/xfs_buf.c

@@ -1151,9 +1151,10 @@ pagebuf_iodone(
 void
 pagebuf_ioerror(			/* mark/clear buffer error flag */
 	xfs_buf_t		*pb,	/* buffer to mark		*/
-	unsigned int		error)	/* error to store (0 if none)	*/
+	int			error)	/* error to store (0 if none)	*/
 {
-	pb->pb_error = error;
+	ASSERT(error >= 0 && error <= 0xffff);
+	pb->pb_error = (unsigned short)error;
 	PB_TRACE(pb, "ioerror", (unsigned long)error);
 }
 

fs/xfs/linux/xfs_buf.h

@@ -250,7 +250,7 @@ extern void pagebuf_iodone(		/* mark buffer I/O complete	*/
 
 extern void pagebuf_ioerror(		/* mark buffer in error	(or not) */
 		xfs_buf_t *,		/* buffer to mark		*/
-		unsigned int);		/* error to store (0 if none)	*/
+		int);			/* error to store (0 if none)	*/
 
 extern int pagebuf_iostart(		/* start I/O on a buffer	*/
 		xfs_buf_t *,		/* buffer to start		*/