kexec: return error number directly

This is a cleanup patch to make kexec more clear to return error number
directly.  The variable result is useless, because there is no other
function's return value assignes to it.  So remove it.

Link: http://lkml.kernel.org/r/1464179273-57668-1-git-send-email-mnghuan@gmail.com
Signed-off-by: Minfei Huang <mnghuan@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/kexec_core.c

@@ -147,7 +147,7 @@ static struct page *kimage_alloc_page(struct kimage *image,
 
 int sanity_check_segment_list(struct kimage *image)
 {
-	int result, i;
+	int i;
 	unsigned long nr_segments = image->nr_segments;
 
 	/*
@@ -163,16 +163,15 @@ int sanity_check_segment_list(struct kimage *image)
 	 * simply because addresses are changed to page size
 	 * granularity.
 	 */
-	result = -EADDRNOTAVAIL;
 	for (i = 0; i < nr_segments; i++) {
 		unsigned long mstart, mend;
 
 		mstart = image->segment[i].mem;
 		mend   = mstart + image->segment[i].memsz;
 		if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
-			return result;
+			return -EADDRNOTAVAIL;
 		if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
-			return result;
+			return -EADDRNOTAVAIL;
 	}
 
 	/* Verify our destination addresses do not overlap.
@@ -180,7 +179,6 @@ int sanity_check_segment_list(struct kimage *image)
 	 * through very weird things can happen with no
 	 * easy explanation as one segment stops on another.
 	 */
-	result = -EINVAL;
 	for (i = 0; i < nr_segments; i++) {
 		unsigned long mstart, mend;
 		unsigned long j;
@@ -194,7 +192,7 @@ int sanity_check_segment_list(struct kimage *image)
 			pend   = pstart + image->segment[j].memsz;
 			/* Do the segments overlap ? */
 			if ((mend > pstart) && (mstart < pend))
-				return result;
+				return -EINVAL;
 		}
 	}
 
@@ -203,10 +201,9 @@ int sanity_check_segment_list(struct kimage *image)
 	 * and it is easier to check up front than to be surprised
 	 * later on.
 	 */
-	result = -EINVAL;
 	for (i = 0; i < nr_segments; i++) {
 		if (image->segment[i].bufsz > image->segment[i].memsz)
-			return result;
+			return -EINVAL;
 	}
 
 	/*
@@ -220,7 +217,6 @@ int sanity_check_segment_list(struct kimage *image)
 	 */
 
 	if (image->type == KEXEC_TYPE_CRASH) {
-		result = -EADDRNOTAVAIL;
 		for (i = 0; i < nr_segments; i++) {
 			unsigned long mstart, mend;
 
@@ -229,7 +225,7 @@ int sanity_check_segment_list(struct kimage *image)
 			/* Ensure we are within the crash kernel limits */
 			if ((mstart < crashk_res.start) ||
 			    (mend > crashk_res.end))
-				return result;
+				return -EADDRNOTAVAIL;
 		}
 	}