[PATCH 3.16.y-ckt 048/216] nfs41: fix nfs4_proc_layoutget error handling

Luis Henriques
2015-01-12T18:28:22Z

From: Peng Tao <tao.peng@primarydata.com>

commit 4bd5a980de87d2b5af417485bde97b8eb3d6cf6a upstream.

nfs4_layoutget_release() drops layout hdr refcnt. Grab the refcnt
early so that it is safe to call .release in case nfs4_alloc_pages
fails.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Fixes: a47970ff78147 ("NFSv4.1: Hold reference to layout hdr in layoutget")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
fs/nfs/nfs4proc.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2768d382a4d1..c401b4de6b01 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7581,6 +7581,9 @@ nfs4_proc_layoutget(struct nfs4_layoutget *lgp, gfp_t gfp_flags)

dprintk("--> %s\n", __func__);

+ /* nfs4_layoutget_release calls pnfs_put_layout_hdr */
+ pnfs_get_layout_hdr(NFS_I(inode)->layout);
+
lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
if (!lgp->args.layout.pages) {
nfs4_layoutget_release(lgp);
@@ -7593,9 +7596,6 @@ nfs4_proc_layoutget(struct nfs4_layoutget *lgp, gfp_t gfp_flags)
lgp->res.seq_res.sr_slot = NULL;
nfs4_init_sequence(&lgp->args.seq_args, &lgp->res.seq_res, 0);

- /* nfs4_layoutget_release calls pnfs_put_layout_hdr */
- pnfs_get_layout_hdr(NFS_I(inode)->layout);
-
task = rpc_run_task(&task_setup_data);
if (IS_ERR(task))
return ERR_CAST(task);
--
2.1.4