staging: lustre: llite: reduce indent in ll_dir_read

Instead of making a large chunk of code conditional
based on if a page is valid we reverse the page
validity test and exit the loop if the page is invalid
instead. This allows a section of code to reduce its
indentation one level.
Signed-off-by: wang di <di.wang@intel.com>
Reviewed-on: http://review.whamcloud.com/10761
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4906Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/dir.c

@@ -508,15 +508,15 @@ int ll_dir_read(struct inode *inode, struct md_op_data *op_data,
 	while (rc == 0 && !done) {
 		struct lu_dirpage *dp;
 		struct lu_dirent  *ent;
-
-		if (!IS_ERR(page)) {
-			/*
-			 * If page is empty (end of directory is reached),
-			 * use this value.
-			 */
-			__u64 hash = MDS_DIR_END_OFF;
+		__u64 hash;
 		__u64 next;
 
+		if (IS_ERR(page)) {
+			rc = PTR_ERR(page);
+			break;
+		}
+
+		hash = MDS_DIR_END_OFF;
 		dp = page_address(page);
 		for (ent = lu_dirent_start(dp); ent && !done;
 		     ent = lu_dirent_next(ent)) {
@@ -593,9 +593,6 @@ int ll_dir_read(struct inode *inode, struct md_op_data *op_data,
 			pos = hash;
 			ll_release_page(page, 0);
 		}
-		} else {
-			rc = PTR_ERR(page);
-		}
 	}
 
 	ctx->pos = pos;