xfs: reflow the tail end of xfs_rtallocate_extent_block

Change polarity of a check so that the successful case of being able to
allocate an extent is in the main path of the function and error handling
is on a branch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>

fs/xfs/xfs_rtalloc.c

@@ -289,16 +289,24 @@ xfs_rtallocate_extent_block(
 		if (error)
 			return error;
 	}
+
 	/*
 	 * Searched the whole thing & didn't find a maxlen free extent.
 	 */
-	if (minlen <= maxlen && besti != -1) {
-		xfs_rtxlen_t	p;	/* amount to trim length by */
+	if (minlen > maxlen || besti == -1) {
+		/*
+		 * Allocation failed.  Set *nextp to the next block to try.
+		 */
+		*nextp = next;
+		return -ENOSPC;
+	}
 
 	/*
 	 * If size should be a multiple of prod, make that so.
 	 */
 	if (prod > 1) {
+		xfs_rtxlen_t	p;	/* amount to trim length by */
+
 		div_u64_rem(bestlen, prod, &p);
 		if (p)
 			bestlen -= p;
@@ -313,12 +321,6 @@ xfs_rtallocate_extent_block(
 	*len = bestlen;
 	*rtx = besti;
 	return 0;
-	}
-	/*
-	 * Allocation failed.  Set *nextp to the next block to try.
-	 */
-	*nextp = next;
-	return -ENOSPC;
 }
 
 /*