[PATCH 3.17 081/141] nfs: fix pnfs direct write memory leak

Greg Kroah-Hartman
2014-11-19T22:19:44Z

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

commit 8c393f9a721c30a030049a680e1bf896669bb279 upstream.

For pNFS direct writes, layout driver may dynamically allocate ds_cinfo.buckets.
So we need to take care to free them when freeing dreq.

Ideally this needs to be done inside layout driver where ds_cinfo.buckets
are allocated. But buckets are attached to dreq and reused across LD IO iterations.
So I feel it's OK to free them in the generic layer.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/nfs/direct.c | 1 +
include/linux/nfs_xdr.h | 11 +++++++++++
2 files changed, 12 insertions(+)

--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -270,6 +270,7 @@ static void nfs_direct_req_free(struct k
{
struct nfs_direct_req *dreq = container_of(kref, struct nfs_direct_req, kref);

+ nfs_free_pnfs_ds_cinfo(&dreq->ds_cinfo);
if (dreq->l_ctx != NULL)
nfs_put_lock_context(dreq->l_ctx);
if (dreq->ctx != NULL)
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1232,11 +1232,22 @@ struct nfs41_free_stateid_res {
unsigned int status;
};

+static inline void
+nfs_free_pnfs_ds_cinfo(struct pnfs_ds_commit_info *cinfo)
+{
+ kfree(cinfo->buckets);
+}
+
#else

struct pnfs_ds_commit_info {
};

+static inline void
+nfs_free_pnfs_ds_cinfo(struct pnfs_ds_commit_info *cinfo)
+{
+}
+
#endif /* CONFIG_NFS_V4_1 */

struct nfs_page;