From: Sage Weil <sage@newdream.net>
Date: Sat, 11 Sep 2010 17:55:25 +0000 (-0700)
Subject: ceph: fix file offset wrapping at 4GB on 32-bit archs
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=a77d9f7dce7600058d56f0670ed29d77abffcde2;p=openwrt%2Fstaging%2Fblogic.git

ceph: fix file offset wrapping at 4GB on 32-bit archs

Cast the value before shifting so that we don't run out of bits with a
32-bit unsigned long.  This fixes wrapping of high file offsets into the
low 4GB of a file on disk, and the subsequent data corruption for large
files.

Signed-off-by: Sage Weil <sage@newdream.net>
---

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 4cfce1ee31fa..50461b8c23a4 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -766,7 +766,8 @@ get_more_pages:
 			/* ok */
 			if (locked_pages == 0) {
 				/* prepare async write request */
-				offset = page->index << PAGE_CACHE_SHIFT;
+				offset = (unsigned long long)page->index
+					<< PAGE_CACHE_SHIFT;
 				len = wsize;
 				req = ceph_osdc_new_request(&client->osdc,
 					    &ci->i_layout,