From b3c000ae15b2004755de6efad16babfb65766a61 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Tue, 22 May 2012 13:55:11 +1000
Subject: [PATCH] --- yaml --- r: 305942 b: refs/heads/master c:
 9b1215c102d4b12f6c815d7fdd35d0628db35b28 h: refs/heads/master v: v3

---
 [refs]                    |  2 +-
 trunk/drivers/md/bitmap.c | 16 +++++++++-------
 trunk/drivers/md/bitmap.h |  2 +-
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/[refs] b/[refs]
index 326bb39eaa78..7654a183086a 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1ec885cdd01a9ad867dbb9fd32a1bfcc0875c486
+refs/heads/master: 9b1215c102d4b12f6c815d7fdd35d0628db35b28
diff --git a/trunk/drivers/md/bitmap.c b/trunk/drivers/md/bitmap.c
index c98f2fee1bd0..7a3be0d4103e 100644
--- a/trunk/drivers/md/bitmap.c
+++ b/trunk/drivers/md/bitmap.c
@@ -203,9 +203,13 @@ static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
 
 		bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
 
-		if (page->index == store->file_pages-1)
-			size = roundup(store->last_page_size,
+		if (page->index == store->file_pages-1) {
+			int last_page_size = store->bytes & (PAGE_SIZE-1);
+			if (last_page_size == 0)
+				last_page_size = PAGE_SIZE;
+			size = roundup(last_page_size,
 				       bdev_logical_block_size(bdev));
+		}
 		/* Just make sure we aren't corrupting data or
 		 * metadata
 		 */
@@ -973,6 +977,8 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
 	if (!bitmap->mddev->bitmap_info.external)
 		bytes += sizeof(bitmap_super_t);
 
+	store->bytes = bytes;
+
 	num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
 
 	if (file && i_size_read(file->f_mapping->host) < bytes) {
@@ -1042,8 +1048,6 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
 
 			oldindex = index;
 
-			store->last_page_size = count;
-
 			if (outofdate) {
 				/*
 				 * if bitmap is out of date, dirty the
@@ -1965,9 +1969,7 @@ space_store(struct mddev *mddev, const char *buf, size_t len)
 		return -EINVAL;
 
 	if (mddev->bitmap &&
-	    sectors  < ((mddev->bitmap->storage.file_pages - 1)
-			      * PAGE_SIZE
-			+ mddev->bitmap->storage.last_page_size + 511) >> 9)
+	    sectors < (mddev->bitmap->storage.bytes + 511) >> 9)
 		return -EFBIG; /* Bitmap is too big for this small space */
 
 	/* could make sure it isn't too big, but that isn't really
diff --git a/trunk/drivers/md/bitmap.h b/trunk/drivers/md/bitmap.h
index 162ab095b866..26689260e179 100644
--- a/trunk/drivers/md/bitmap.h
+++ b/trunk/drivers/md/bitmap.h
@@ -197,7 +197,7 @@ struct bitmap {
 		unsigned long *filemap_attr;	/* attributes associated
 						 * w/ filemap pages */
 		unsigned long file_pages;	/* number of pages in the file*/
-		int last_page_size;		/* bytes in the last page */
+		unsigned long bytes;		/* total bytes in the bitmap */
 	} storage;
 
 	unsigned long flags;