From: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Date: Fri, 17 Dec 2010 17:55:59 +0000 (-0800)
Subject: ceph: handle partial result from get_user_pages
X-Git-Tag: v3.0~2590^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=361cf40519a491f68b28ad90225e4611c4bf8e12;p=platform%2Fkernel%2Flinux-amlogic.git

ceph: handle partial result from get_user_pages

The get_user_pages() helper can return fewer than the requested pages.
Error out in that case, and clean up the partial result.

Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
---

diff --git a/net/ceph/pagevec.c b/net/ceph/pagevec.c
index 01947a5..1a040e6 100644
--- a/net/ceph/pagevec.c
+++ b/net/ceph/pagevec.c
@@ -26,12 +26,12 @@ struct page **ceph_get_direct_page_vector(const char __user *data,
 	rc = get_user_pages(current, current->mm, (unsigned long)data,
 			    num_pages, write_page, 0, pages, NULL);
 	up_read(&current->mm->mmap_sem);
-	if (rc < 0)
+	if (rc < num_pages)
 		goto fail;
 	return pages;
 
 fail:
-	kfree(pages);
+	ceph_put_page_vector(pages, rc > 0 ? rc : 0, false);
 	return ERR_PTR(rc);
 }
 EXPORT_SYMBOL(ceph_get_direct_page_vector);