NFSv4/pnfs: Fix a page lock leak in nfs_pageio_resend()

If the attempt to resend the pages fails, we need to ensure that we
clean up those pages that were not transmitted.

Fixes: d600ad1f2bdb ("NFS41: pop some layoutget errors to application")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.5+

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index ed4e1b0..15c2547 100644 (file)
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -1251,20 +1251,22 @@ static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc,
 int nfs_pageio_resend(struct nfs_pageio_descriptor *desc,
                      struct nfs_pgio_header *hdr)
 {
-       LIST_HEAD(failed);
+       LIST_HEAD(pages);
 
        desc->pg_io_completion = hdr->io_completion;
        desc->pg_dreq = hdr->dreq;
-       while (!list_empty(&hdr->pages)) {
-               struct nfs_page *req = nfs_list_entry(hdr->pages.next);
+       list_splice_init(&hdr->pages, &pages);
+       while (!list_empty(&pages)) {
+               struct nfs_page *req = nfs_list_entry(pages.next);
 
                if (!nfs_pageio_add_request(desc, req))
-                       nfs_list_move_request(req, &failed);
+                       break;
        }
        nfs_pageio_complete(desc);
-       if (!list_empty(&failed)) {
-               list_move(&failed, &hdr->pages);
-               return desc->pg_error < 0 ? desc->pg_error : -EIO;
+       if (!list_empty(&pages)) {
+               int err = desc->pg_error < 0 ? desc->pg_error : -EIO;
+               hdr->completion_ops->error_cleanup(&pages, err);
+               return err;
        }
        return 0;
 }