SUNRPC: New xdr_streams XDR encoder API

Now that all client-side XDR encoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC arg *] anywhere.  We can construct an xdr_stream in the
generic RPC code, instead of in each encoder function.

Also, all the client-side encoder functions return 0 now, making a
return value superfluous.  Take this opportunity to convert them to
return void instead.

This is a refactoring change.  It should not cause different behavior.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 56 insertions, 91 deletions

diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
index a9b848edbd2e..8f3acbec761f 100644
--- a/fs/nfs/nfs2xdr.c
+++ b/fs/nfs/nfs2xdr.c
@@ -558,14 +558,11 @@ out_default:
  * "NFS: Network File System Protocol Specification".
  */
 
-static int nfs2_xdr_enc_fhandle(struct rpc_rqst *req, __be32 *p,
-                                const struct nfs_fh *fh)
+static void nfs2_xdr_enc_fhandle(struct rpc_rqst *req,
+                                 struct xdr_stream *xdr,
+                                 const struct nfs_fh *fh)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_fhandle(&xdr, fh);
-        return 0;
+        encode_fhandle(xdr, fh);
 }
 
 /*
@@ -576,37 +573,28 @@ static int nfs2_xdr_enc_fhandle(struct rpc_rqst *req, __be32 *p,
  *              sattr attributes;
  *      };
  */
-static int nfs2_xdr_enc_sattrargs(struct rpc_rqst *req, __be32 *p,
-                                  const struct nfs_sattrargs *args)
+static void nfs2_xdr_enc_sattrargs(struct rpc_rqst *req,
+                                   struct xdr_stream *xdr,
+                                   const struct nfs_sattrargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_fhandle(&xdr, args->fh);
-        encode_sattr(&xdr, args->sattr);
-        return 0;
+        encode_fhandle(xdr, args->fh);
+        encode_sattr(xdr, args->sattr);
 }
 
-static int nfs2_xdr_enc_diropargs(struct rpc_rqst *req, __be32 *p,
-                                  const struct nfs_diropargs *args)
+static void nfs2_xdr_enc_diropargs(struct rpc_rqst *req,
+                                   struct xdr_stream *xdr,
+                                   const struct nfs_diropargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs(&xdr, args->fh, args->name, args->len);
-        return 0;
+        encode_diropargs(xdr, args->fh, args->name, args->len);
 }
 
-static int nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req, __be32 *p,
-                                     const struct nfs_readlinkargs *args)
+static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req,
+                                      struct xdr_stream *xdr,
+                                      const struct nfs_readlinkargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_fhandle(&xdr, args->fh);
+        encode_fhandle(xdr, args->fh);
         prepare_reply_buffer(req, args->pages, args->pgbase,
                                         args->pglen, NFS_readlinkres_sz);
-        return 0;
 }
 
 /*
@@ -634,17 +622,14 @@ static void encode_readargs(struct xdr_stream *xdr,
         *p = cpu_to_be32(count);
 }
 
-static int nfs2_xdr_enc_readargs(struct rpc_rqst *req, __be32 *p,
-                                 const struct nfs_readargs *args)
+static void nfs2_xdr_enc_readargs(struct rpc_rqst *req,
+                                  struct xdr_stream *xdr,
+                                  const struct nfs_readargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_readargs(&xdr, args);
+        encode_readargs(xdr, args);
         prepare_reply_buffer(req, args->pages, args->pgbase,
                                         args->count, NFS_readres_sz);
         req->rq_rcv_buf.flags |= XDRBUF_READ;
-        return 0;
 }
 
 /*
@@ -677,15 +662,12 @@ static void encode_writeargs(struct xdr_stream *xdr,
         xdr_write_pages(xdr, args->pages, args->pgbase, count);
 }
 
-static int nfs2_xdr_enc_writeargs(struct rpc_rqst *req, __be32 *p,
-                                  const struct nfs_writeargs *args)
+static void nfs2_xdr_enc_writeargs(struct rpc_rqst *req,
+                                   struct xdr_stream *xdr,
+                                   const struct nfs_writeargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_writeargs(&xdr, args);
-        xdr.buf->flags |= XDRBUF_WRITE;
-        return 0;
+        encode_writeargs(xdr, args);
+        xdr->buf->flags |= XDRBUF_WRITE;
 }
 
 /*
@@ -696,25 +678,19 @@ static int nfs2_xdr_enc_writeargs(struct rpc_rqst *req, __be32 *p,
  *              sattr attributes;
  *      };
  */
-static int nfs2_xdr_enc_createargs(struct rpc_rqst *req, __be32 *p,
-                                   const struct nfs_createargs *args)
+static void nfs2_xdr_enc_createargs(struct rpc_rqst *req,
+                                    struct xdr_stream *xdr,
+                                    const struct nfs_createargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs(&xdr, args->fh, args->name, args->len);
-        encode_sattr(&xdr, args->sattr);
-        return 0;
+        encode_diropargs(xdr, args->fh, args->name, args->len);
+        encode_sattr(xdr, args->sattr);
 }
 
-static int nfs2_xdr_enc_removeargs(struct rpc_rqst *req, __be32 *p,
-                                   const struct nfs_removeargs *args)
+static void nfs2_xdr_enc_removeargs(struct rpc_rqst *req,
+                                    struct xdr_stream *xdr,
+                                    const struct nfs_removeargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs(&xdr, args->fh, args->name.name, args->name.len);
-        return 0;
+        encode_diropargs(xdr, args->fh, args->name.name, args->name.len);
 }
 
 /*
@@ -725,17 +701,15 @@ static int nfs2_xdr_enc_removeargs(struct rpc_rqst *req, __be32 *p,
  *              diropargs to;
  *      };
  */
-static int nfs2_xdr_enc_renameargs(struct rpc_rqst *req, __be32 *p,
-                                   const struct nfs_renameargs *args)
+static void nfs2_xdr_enc_renameargs(struct rpc_rqst *req,
+                                    struct xdr_stream *xdr,
+                                    const struct nfs_renameargs *args)
 {
         const struct qstr *old = args->old_name;
         const struct qstr *new = args->new_name;
-        struct xdr_stream xdr;
 
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs(&xdr, args->old_dir, old->name, old->len);
-        encode_diropargs(&xdr, args->new_dir, new->name, new->len);
-        return 0;
+        encode_diropargs(xdr, args->old_dir, old->name, old->len);
+        encode_diropargs(xdr, args->new_dir, new->name, new->len);
 }
 
 /*
@@ -746,15 +720,12 @@ static int nfs2_xdr_enc_renameargs(struct rpc_rqst *req, __be32 *p,
  *              diropargs to;
  *      };
  */
-static int nfs2_xdr_enc_linkargs(struct rpc_rqst *req, __be32 *p,
-                                 const struct nfs_linkargs *args)
+static void nfs2_xdr_enc_linkargs(struct rpc_rqst *req,
+                                  struct xdr_stream *xdr,
+                                  const struct nfs_linkargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_fhandle(&xdr, args->fromfh);
-        encode_diropargs(&xdr, args->tofh, args->toname, args->tolen);
-        return 0;
+        encode_fhandle(xdr, args->fromfh);
+        encode_diropargs(xdr, args->tofh, args->toname, args->tolen);
 }
 
 /*
@@ -766,16 +737,13 @@ static int nfs2_xdr_enc_linkargs(struct rpc_rqst *req, __be32 *p,
  *              sattr attributes;
  *      };
  */
-static int nfs2_xdr_enc_symlinkargs(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs_symlinkargs *args)
+static void nfs2_xdr_enc_symlinkargs(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs_symlinkargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs(&xdr, args->fromfh, args->fromname, args->fromlen);
-        encode_path(&xdr, args->pages, args->pathlen);
-        encode_sattr(&xdr, args->sattr);
-        return 0;
+        encode_diropargs(xdr, args->fromfh, args->fromname, args->fromlen);
+        encode_path(xdr, args->pages, args->pathlen);
+        encode_sattr(xdr, args->sattr);
 }
 
 /*
@@ -799,16 +767,13 @@ static void encode_readdirargs(struct xdr_stream *xdr,
         *p = cpu_to_be32(args->count);
 }
 
-static int nfs2_xdr_enc_readdirargs(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs_readdirargs *args)
+static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs_readdirargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_readdirargs(&xdr, args);
+        encode_readdirargs(xdr, args);
         prepare_reply_buffer(req, args->pages, 0,
                                         args->count, NFS_readdirres_sz);
-        return 0;
 }
 
 /*
@@ -1184,7 +1149,7 @@ int nfs_stat_to_errno(enum nfs_stat status)
 #define PROC(proc, argtype, restype, timer)                             \
 [NFSPROC_##proc] = {                                                    \
         .p_proc     =  NFSPROC_##proc,                                  \
-        .p_encode   =  (kxdrproc_t)nfs2_xdr_enc_##argtype,              \
+        .p_encode   =  (kxdreproc_t)nfs2_xdr_enc_##argtype,             \
         .p_decode   =  (kxdrproc_t)nfs2_xdr_dec_##restype,              \
         .p_arglen   =  NFS_##argtype##_sz,                              \
         .p_replen   =  NFS_##restype##_sz,                              \