[ 168/171] libceph: Unlock unprocessed pages in start_read() error path

Greg Kroah-Hartman
2013-01-15T23:17:24Z

From: David Zafman <david.zafman@inktank.com>

Function start_read() can get an error before processing all pages.
It must not only release the remaining pages, but unlock them too.

This fixes http://tracker.newdream.net/issues/3370

Signed-off-by: David Zafman <david.zafman@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
(cherry picked from commit 8884d53dd63b1d9315b343564fcbe1ede004a99e)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ceph/addr.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -267,6 +267,14 @@ static void finish_read(struct ceph_osd_
kfree(req->r_pages);
}

+static void ceph_unlock_page_vector(struct page **pages, int num_pages)
+{
+ int i;
+
+ for (i = 0; i < num_pages; i++)
+ unlock_page(pages[i]);
+}
+
/*
* start an async read(ahead) operation. return nr_pages we submitted
* a read for on success, or negative error code.
@@ -347,6 +355,7 @@ static int start_read(struct inode *inod
return nr_pages;

out_pages:
+ ceph_unlock_page_vector(pages, nr_pages);
ceph_release_page_vector(pages, nr_pages);
out:
ceph_osdc_put_request(req);