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, 93 insertions, 148 deletions

diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index 15c93ccd90c5..ae1b1a43f05e 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -835,14 +835,11 @@ static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
  *              nfs_fh3  object;
  *      };
  */
-static int nfs3_xdr_enc_getattr3args(struct rpc_rqst *req, __be32 *p,
-                                     const struct nfs_fh *fh)
+static void nfs3_xdr_enc_getattr3args(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_nfs_fh3(&xdr, fh);
-        return 0;
+        encode_nfs_fh3(xdr, fh);
 }
 
 /*
@@ -876,16 +873,13 @@ static void encode_sattrguard3(struct xdr_stream *xdr,
         }
 }
 
-static int nfs3_xdr_enc_setattr3args(struct rpc_rqst *req, __be32 *p,
-                                     const struct nfs3_sattrargs *args)
+static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
+                                      struct xdr_stream *xdr,
+                                      const struct nfs3_sattrargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_nfs_fh3(&xdr, args->fh);
-        encode_sattr3(&xdr, args->sattr);
-        encode_sattrguard3(&xdr, args);
-        return 0;
+        encode_nfs_fh3(xdr, args->fh);
+        encode_sattr3(xdr, args->sattr);
+        encode_sattrguard3(xdr, args);
 }
 
 /*
@@ -895,14 +889,11 @@ static int nfs3_xdr_enc_setattr3args(struct rpc_rqst *req, __be32 *p,
  *              diropargs3  what;
  *      };
  */
-static int nfs3_xdr_enc_lookup3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs3_diropargs *args)
+static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs3_diropargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs3(&xdr, args->fh, args->name, args->len);
-        return 0;
+        encode_diropargs3(xdr, args->fh, args->name, args->len);
 }
 
 /*
@@ -920,14 +911,11 @@ static void encode_access3args(struct xdr_stream *xdr,
         encode_uint32(xdr, args->access);
 }
 
-static int nfs3_xdr_enc_access3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs3_accessargs *args)
+static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs3_accessargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_access3args(&xdr, args);
-        return 0;
+        encode_access3args(xdr, args);
 }
 
 /*
@@ -937,16 +925,13 @@ static int nfs3_xdr_enc_access3args(struct rpc_rqst *req, __be32 *p,
  *              nfs_fh3 symlink;
  *      };
  */
-static int nfs3_xdr_enc_readlink3args(struct rpc_rqst *req, __be32 *p,
-                                      const struct nfs3_readlinkargs *args)
+static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
+                                       struct xdr_stream *xdr,
+                                       const struct nfs3_readlinkargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_nfs_fh3(&xdr, args->fh);
+        encode_nfs_fh3(xdr, args->fh);
         prepare_reply_buffer(req, args->pages, args->pgbase,
                                         args->pglen, NFS3_readlinkres_sz);
-        return 0;
 }
 
 /*
@@ -970,17 +955,14 @@ static void encode_read3args(struct xdr_stream *xdr,
         *p = cpu_to_be32(args->count);
 }
 
-static int nfs3_xdr_enc_read3args(struct rpc_rqst *req, __be32 *p,
-                                  const struct nfs_readargs *args)
+static void nfs3_xdr_enc_read3args(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_read3args(&xdr, args);
+        encode_read3args(xdr, args);
         prepare_reply_buffer(req, args->pages, args->pgbase,
                                         args->count, NFS3_readres_sz);
         req->rq_rcv_buf.flags |= XDRBUF_READ;
-        return 0;
 }
 
 /*
@@ -1015,15 +997,12 @@ static void encode_write3args(struct xdr_stream *xdr,
         xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
 }
 
-static int nfs3_xdr_enc_write3args(struct rpc_rqst *req, __be32 *p,
-                                   const struct nfs_writeargs *args)
+static void nfs3_xdr_enc_write3args(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_write3args(&xdr, args);
-        xdr.buf->flags |= XDRBUF_WRITE;
-        return 0;
+        encode_write3args(xdr, args);
+        xdr->buf->flags |= XDRBUF_WRITE;
 }
 
 /*
@@ -1065,15 +1044,12 @@ static void encode_createhow3(struct xdr_stream *xdr,
         }
 }
 
-static int nfs3_xdr_enc_create3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs3_createargs *args)
+static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs3_createargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs3(&xdr, args->fh, args->name, args->len);
-        encode_createhow3(&xdr, args);
-        return 0;
+        encode_diropargs3(xdr, args->fh, args->name, args->len);
+        encode_createhow3(xdr, args);
 }
 
 /*
@@ -1084,15 +1060,12 @@ static int nfs3_xdr_enc_create3args(struct rpc_rqst *req, __be32 *p,
  *              sattr3          attributes;
  *      };
  */
-static int nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req, __be32 *p,
-                                   const struct nfs3_mkdirargs *args)
+static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
+                                    struct xdr_stream *xdr,
+                                    const struct nfs3_mkdirargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs3(&xdr, args->fh, args->name, args->len);
-        encode_sattr3(&xdr, args->sattr);
-        return 0;
+        encode_diropargs3(xdr, args->fh, args->name, args->len);
+        encode_sattr3(xdr, args->sattr);
 }
 
 /*
@@ -1115,15 +1088,12 @@ static void encode_symlinkdata3(struct xdr_stream *xdr,
         encode_nfspath3(xdr, args->pages, args->pathlen);
 }
 
-static int nfs3_xdr_enc_symlink3args(struct rpc_rqst *req, __be32 *p,
-                                     const struct nfs3_symlinkargs *args)
+static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
+                                      struct xdr_stream *xdr,
+                                      const struct nfs3_symlinkargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs3(&xdr, args->fromfh, args->fromname, args->fromlen);
-        encode_symlinkdata3(&xdr, args);
-        return 0;
+        encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
+        encode_symlinkdata3(xdr, args);
 }
 
 /*
@@ -1178,15 +1148,12 @@ static void encode_mknoddata3(struct xdr_stream *xdr,
         }
 }
 
-static int nfs3_xdr_enc_mknod3args(struct rpc_rqst *req, __be32 *p,
-                                   const struct nfs3_mknodargs *args)
+static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
+                                    struct xdr_stream *xdr,
+                                    const struct nfs3_mknodargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_diropargs3(&xdr, args->fh, args->name, args->len);
-        encode_mknoddata3(&xdr, args);
-        return 0;
+        encode_diropargs3(xdr, args->fh, args->name, args->len);
+        encode_mknoddata3(xdr, args);
 }
 
 /*
@@ -1196,14 +1163,11 @@ static int nfs3_xdr_enc_mknod3args(struct rpc_rqst *req, __be32 *p,
  *              diropargs3  object;
  *      };
  */
-static int nfs3_xdr_enc_remove3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs_removeargs *args)
+static void nfs3_xdr_enc_remove3args(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_diropargs3(&xdr, args->fh, args->name.name, args->name.len);
-        return 0;
+        encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
 }
 
 /*
@@ -1214,17 +1178,15 @@ static int nfs3_xdr_enc_remove3args(struct rpc_rqst *req, __be32 *p,
  *              diropargs3      to;
  *      };
  */
-static int nfs3_xdr_enc_rename3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs_renameargs *args)
+static void nfs3_xdr_enc_rename3args(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_diropargs3(&xdr, args->old_dir, old->name, old->len);
-        encode_diropargs3(&xdr, args->new_dir, new->name, new->len);
-        return 0;
+        encode_diropargs3(xdr, args->old_dir, old->name, old->len);
+        encode_diropargs3(xdr, args->new_dir, new->name, new->len);
 }
 
 /*
@@ -1235,15 +1197,12 @@ static int nfs3_xdr_enc_rename3args(struct rpc_rqst *req, __be32 *p,
  *              diropargs3      link;
  *      };
  */
-static int nfs3_xdr_enc_link3args(struct rpc_rqst *req, __be32 *p,
-                                  const struct nfs3_linkargs *args)
+static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
+                                   struct xdr_stream *xdr,
+                                   const struct nfs3_linkargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_nfs_fh3(&xdr, args->fromfh);
-        encode_diropargs3(&xdr, args->tofh, args->toname, args->tolen);
-        return 0;
+        encode_nfs_fh3(xdr, args->fromfh);
+        encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
 }
 
 /*
@@ -1269,16 +1228,13 @@ static void encode_readdir3args(struct xdr_stream *xdr,
         *p = cpu_to_be32(args->count);
 }
 
-static int nfs3_xdr_enc_readdir3args(struct rpc_rqst *req, __be32 *p,
-                                     const struct nfs3_readdirargs *args)
+static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
+                                      struct xdr_stream *xdr,
+                                      const struct nfs3_readdirargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_readdir3args(&xdr, args);
+        encode_readdir3args(xdr, args);
         prepare_reply_buffer(req, args->pages, 0,
                                 args->count, NFS3_readdirres_sz);
-        return 0;
 }
 
 /*
@@ -1312,16 +1268,13 @@ static void encode_readdirplus3args(struct xdr_stream *xdr,
         *p = cpu_to_be32(args->count);
 }
 
-static int nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req, __be32 *p,
-                                         const struct nfs3_readdirargs *args)
+static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
+                                          struct xdr_stream *xdr,
+                                          const struct nfs3_readdirargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_readdirplus3args(&xdr, args);
+        encode_readdirplus3args(xdr, args);
         prepare_reply_buffer(req, args->pages, 0,
                                 args->count, NFS3_readdirres_sz);
-        return 0;
 }
 
 /*
@@ -1345,57 +1298,49 @@ static void encode_commit3args(struct xdr_stream *xdr,
         *p = cpu_to_be32(args->count);
 }
 
-static int nfs3_xdr_enc_commit3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs_writeargs *args)
+static void nfs3_xdr_enc_commit3args(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_commit3args(&xdr, args);
-        return 0;
+        encode_commit3args(xdr, args);
 }
 
 #ifdef CONFIG_NFS_V3_ACL
 
-static int nfs3_xdr_enc_getacl3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs3_getaclargs *args)
+static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs3_getaclargs *args)
 {
-        struct xdr_stream xdr;
-
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_nfs_fh3(&xdr, args->fh);
-        encode_uint32(&xdr, args->mask);
+        encode_nfs_fh3(xdr, args->fh);
+        encode_uint32(xdr, args->mask);
         if (args->mask & (NFS_ACL | NFS_DFACL))
                 prepare_reply_buffer(req, args->pages, 0,
                                         NFSACL_MAXPAGES << PAGE_SHIFT,
                                         ACL3_getaclres_sz);
-        return 0;
 }
 
-static int nfs3_xdr_enc_setacl3args(struct rpc_rqst *req, __be32 *p,
-                                    const struct nfs3_setaclargs *args)
+static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
+                                     struct xdr_stream *xdr,
+                                     const struct nfs3_setaclargs *args)
 {
-        struct xdr_stream xdr;
         unsigned int base;
         int error;
 
-        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-        encode_nfs_fh3(&xdr, NFS_FH(args->inode));
-        encode_uint32(&xdr, args->mask);
+        encode_nfs_fh3(xdr, NFS_FH(args->inode));
+        encode_uint32(xdr, args->mask);
         if (args->npages != 0)
-                xdr_write_pages(&xdr, args->pages, 0, args->len);
+                xdr_write_pages(xdr, args->pages, 0, args->len);
 
         base = req->rq_slen;
-        error = nfsacl_encode(xdr.buf, base, args->inode,
+        error = nfsacl_encode(xdr->buf, base, args->inode,
                             (args->mask & NFS_ACL) ?
                             args->acl_access : NULL, 1, 0);
         BUG_ON(error < 0);
-        error = nfsacl_encode(xdr.buf, base + error, args->inode,
+        error = nfsacl_encode(xdr->buf, base + error, args->inode,
                             (args->mask & NFS_DFACL) ?
                             args->acl_default : NULL, 1,
                             NFS_ACL_DEFAULT);
         BUG_ON(error < 0);
-        return 0;
 }
 
 #endif  /* CONFIG_NFS_V3_ACL */
@@ -2506,7 +2451,7 @@ out_default:
 #define PROC(proc, argtype, restype, timer)                             \
 [NFS3PROC_##proc] = {                                                   \
         .p_proc      = NFS3PROC_##proc,                                 \
-        .p_encode    = (kxdrproc_t)nfs3_xdr_enc_##argtype##3args,       \
+        .p_encode    = (kxdreproc_t)nfs3_xdr_enc_##argtype##3args,      \
         .p_decode    = (kxdrproc_t)nfs3_xdr_dec_##restype##3res,        \
         .p_arglen    = NFS3_##argtype##args_sz,                         \
         .p_replen    = NFS3_##restype##res_sz,                          \
@@ -2549,7 +2494,7 @@ struct rpc_version		nfs_version3 = {
 static struct rpc_procinfo      nfs3_acl_procedures[] = {
         [ACLPROC3_GETACL] = {
                 .p_proc = ACLPROC3_GETACL,
-                .p_encode = (kxdrproc_t)nfs3_xdr_enc_getacl3args,
+                .p_encode = (kxdreproc_t)nfs3_xdr_enc_getacl3args,
                 .p_decode = (kxdrproc_t)nfs3_xdr_dec_getacl3res,
                 .p_arglen = ACL3_getaclargs_sz,
                 .p_replen = ACL3_getaclres_sz,
@@ -2558,7 +2503,7 @@ static struct rpc_procinfo	nfs3_acl_procedures[] = {
         },
         [ACLPROC3_SETACL] = {
                 .p_proc = ACLPROC3_SETACL,
-                .p_encode = (kxdrproc_t)nfs3_xdr_enc_setacl3args,
+                .p_encode = (kxdreproc_t)nfs3_xdr_enc_setacl3args,
                 .p_decode = (kxdrproc_t)nfs3_xdr_dec_setacl3res,
                 .p_arglen = ACL3_setaclargs_sz,
                 .p_replen = ACL3_setaclres_sz,