[PATCH v12 22/24] nfs: push localio nfsd_file_put call out to client

[Mike Snitzer <snitzer@kernel.org>]

Change nfsd_open_local_fh() to return an nfsd_file, instead of file,
and move associated reference counting to the nfs client's
nfs_local_open_fh().

This is the first step in allowing proper use of nfsd_file for localio
(such that the benefits of nfsd's filecache can be realized).

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
---
 fs/nfs/localio.c           |  7 +++++--
 fs/nfs_common/nfslocalio.c |  2 +-
 fs/nfsd/localio.c          | 11 ++++-------
 fs/nfsd/vfs.h              |  2 +-
 include/linux/nfslocalio.h |  2 +-
 5 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c
index 38303427e0b3..7d63d7e34643 100644
--- a/fs/nfs/localio.c
+++ b/fs/nfs/localio.c
@@ -237,13 +237,14 @@ nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred,
 		  struct nfs_fh *fh, const fmode_t mode)
 {
 	struct file *filp;
+	struct nfsd_file *nf;
 	int status;
 
 	if (mode & ~(FMODE_READ | FMODE_WRITE))
 		return ERR_PTR(-EINVAL);
 
 	status = nfs_to.nfsd_open_local_fh(clp->cl_nfssvc_net, clp->cl_nfssvc_dom,
-					   clp->cl_rpcclient, cred, fh, mode, &filp);
+					   clp->cl_rpcclient, cred, fh, mode, &nf);
 	if (status < 0) {
 		trace_nfs_local_open_fh(fh, mode, status);
 		switch (status) {
@@ -255,8 +256,10 @@ nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred,
 		case -ETIMEDOUT:
 			status = -EAGAIN;
 		}
-		filp = ERR_PTR(status);
+		return ERR_PTR(status);
 	}
+	filp = get_file(nfs_to.nfsd_file_file(nf));
+	nfs_to.nfsd_file_put(nf);
 	return filp;
 }
 EXPORT_SYMBOL_GPL(nfs_local_open_fh);
diff --git a/fs/nfs_common/nfslocalio.c b/fs/nfs_common/nfslocalio.c
index 087649911b52..f59167e596d3 100644
--- a/fs/nfs_common/nfslocalio.c
+++ b/fs/nfs_common/nfslocalio.c
@@ -98,7 +98,7 @@ static void put_##NFSD_SYMBOL(void)			\
 /* The nfs localio code needs to call into nfsd to map filehandle -> struct nfsd_file */
 extern int nfsd_open_local_fh(struct net *, struct auth_domain *, struct rpc_clnt *,
 			      const struct cred *, const struct nfs_fh *,
-			      const fmode_t, struct file **);
+			      const fmode_t, struct nfsd_file **);
 DEFINE_NFS_TO_NFSD_SYMBOL(nfsd_open_local_fh);
 
 /* The nfs localio code needs to call into nfsd to acquire the nfsd_file */
diff --git a/fs/nfsd/localio.c b/fs/nfsd/localio.c
index 008b935a3a6c..2ceab49f3cb6 100644
--- a/fs/nfsd/localio.c
+++ b/fs/nfsd/localio.c
@@ -32,13 +32,13 @@
  * @cred: cred that the client established
  * @nfs_fh: filehandle to lookup
  * @fmode: fmode_t to use for open
- * @pfilp: returned file pointer that maps to @nfs_fh
+ * @pnf: returned nfsd_file pointer that maps to @nfs_fh
  *
  * This function maps a local fh to a path on a local filesystem.
  * This is useful when the nfs client has the local server mounted - it can
  * avoid all the NFS overhead with reads, writes and commits.
  *
- * On successful return, caller is responsible for calling path_put. Also
+ * On successful return, caller is responsible for calling nfsd_file_put. Also
  * note that this is called from nfs.ko via find_symbol() to avoid an explicit
  * dependency on knfsd. So, there is no forward declaration in a header file
  * for it that is shared with the client.
@@ -49,7 +49,7 @@ int nfsd_open_local_fh(struct net *cl_nfssvc_net,
 			 const struct cred *cred,
 			 const struct nfs_fh *nfs_fh,
 			 const fmode_t fmode,
-			 struct file **pfilp)
+			 struct nfsd_file **pnf)
 {
 	int mayflags = NFSD_MAY_LOCALIO;
 	int status = 0;
@@ -57,7 +57,6 @@ int nfsd_open_local_fh(struct net *cl_nfssvc_net,
 	const struct cred *save_cred;
 	struct svc_cred rq_cred;
 	struct svc_fh fh;
-	struct nfsd_file *nf;
 	__be32 beres;
 
 	if (nfs_fh->size > NFS4_FHSIZE)
@@ -91,13 +90,11 @@ int nfsd_open_local_fh(struct net *cl_nfssvc_net,
 	rpcauth_map_clnt_to_svc_cred_local(rpc_clnt, cred, &rq_cred);
 
 	beres = nfsd_file_acquire_local(cl_nfssvc_net, &rq_cred, rpc_clnt->cl_vers,
-					cl_nfssvc_dom, &fh, mayflags, &nf);
+					cl_nfssvc_dom, &fh, mayflags, pnf);
 	if (beres) {
 		status = nfs_stat_to_errno(be32_to_cpu(beres));
 		goto out_fh_put;
 	}
-	*pfilp = get_file(nf->nf_file);
-	nfsd_file_put(nf);
 out_fh_put:
 	fh_put(&fh);
 	if (rq_cred.cr_group_info)
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index 9720951c49a0..ec8a8aae540b 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -166,7 +166,7 @@ int		nfsd_open_local_fh(struct net *net,
 				   const struct cred *cred,
 				   const struct nfs_fh *nfs_fh,
 				   const fmode_t fmode,
-				   struct file **pfilp);
+				   struct nfsd_file **pnf);
 
 static inline int fh_want_write(struct svc_fh *fh)
 {
diff --git a/include/linux/nfslocalio.h b/include/linux/nfslocalio.h
index 6302d36f9112..7e09ff621d93 100644
--- a/include/linux/nfslocalio.h
+++ b/include/linux/nfslocalio.h
@@ -35,7 +35,7 @@ struct nfsd_file;
 typedef int (*nfs_to_nfsd_open_local_fh_t)(struct net *, struct auth_domain *,
 				struct rpc_clnt *, const struct cred *,
 				const struct nfs_fh *, const fmode_t,
-				struct file **);
+				struct nfsd_file **);
 typedef struct nfsd_file * (*nfs_to_nfsd_file_get_t)(struct nfsd_file *);
 typedef void (*nfs_to_nfsd_file_put_t)(struct nfsd_file *);
 typedef struct file * (*nfs_to_nfsd_file_file_t)(struct nfsd_file *);
-- 
2.44.0