NFSD: Add infrastructure for generating NFSv2 XDR encoders and decoders

NFSD's NFSv2 XDR codecs are hand-maintained; they are being converted
to xdrgen-generated code one RPC procedure at a time. The first step
is to generate and commit the xdrgen C code based on nfs2.x. The
generated code can be refreshed any time nfs2.x is modified by
running "(cd fs/nfsd && make xdrgen)".

Acked-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260916162859.2051-4-cel@kernel.org
Signed-off-by: Chuck Lever <cel@kernel.org>

1 files changed, 298 insertions, 0 deletions

diff --git a/include/linux/sunrpc/xdrgen/nfs2.h b/include/linux/sunrpc/xdrgen/nfs2.h
new file mode 100644
index 000000000000..4a022b670b0c
--- /dev/null
+++ b/include/linux/sunrpc/xdrgen/nfs2.h
@@ -0,0 +1,298 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Generated by xdrgen. Manual edits will be lost. */
+/* XDR specification file: ../../Documentation/sunrpc/xdr/nfs2.x */
+/* XDR specification modification time: Tue Sep  8 11:23:43 2026 */
+
+#ifndef _LINUX_XDRGEN_NFS2_DEF_H
+#define _LINUX_XDRGEN_NFS2_DEF_H
+
+#include <linux/types.h>
+#include <linux/sunrpc/xdrgen/_defs.h>
+
+enum { NFS_MAXDATA = 8192 };
+
+enum { NFS_MAXPATHLEN = 1024 };
+
+enum { NFS_MAXNAMLEN = 255 };
+
+enum { NFS_COOKIESIZE = 4 };
+
+enum { NFS_FHSIZE = 32 };
+
+enum nfsstat {
+	NFS_OK = 0,
+	NFSERR_PERM = 1,
+	NFSERR_NOENT = 2,
+	NFSERR_IO = 5,
+	NFSERR_NXIO = 6,
+	NFSERR_ACCES = 13,
+	NFSERR_EXIST = 17,
+	NFSERR_NODEV = 19,
+	NFSERR_NOTDIR = 20,
+	NFSERR_ISDIR = 21,
+	NFSERR_FBIG = 27,
+	NFSERR_NOSPC = 28,
+	NFSERR_ROFS = 30,
+	NFSERR_NAMETOOLONG = 63,
+	NFSERR_NOTEMPTY = 66,
+	NFSERR_DQUOT = 69,
+	NFSERR_STALE = 70,
+	NFSERR_WFLUSH = 99,
+};
+
+typedef enum nfsstat nfsstat;
+
+enum ftype {
+	NFNON = 0,
+	NFREG = 1,
+	NFDIR = 2,
+	NFBLK = 3,
+	NFCHR = 4,
+	NFLNK = 5,
+};
+
+typedef enum ftype ftype;
+
+typedef u8 fhandle[NFS_FHSIZE];
+
+typedef u8 nfscookie[NFS_COOKIESIZE];
+
+struct timeval {
+	u32 seconds;
+	u32 useconds;
+};
+
+struct fattr {
+	ftype type;
+	u32 mode;
+	u32 nlink;
+	u32 uid;
+	u32 gid;
+	u32 size;
+	u32 blocksize;
+	u32 rdev;
+	u32 blocks;
+	u32 fsid;
+	u32 fileid;
+	struct timeval atime;
+	struct timeval mtime;
+	struct timeval ctime;
+};
+
+struct sattr {
+	u32 mode;
+	u32 uid;
+	u32 gid;
+	u32 size;
+	struct timeval atime;
+	struct timeval mtime;
+};
+
+typedef string filename;
+
+typedef string path;
+
+struct attrstat {
+	nfsstat status;
+	union {
+		struct fattr attributes;
+	} u;
+};
+
+struct diropargs {
+	fhandle dir;
+	filename name;
+};
+
+struct diropok {
+	fhandle file;
+	struct fattr attributes;
+};
+
+struct diropres {
+	nfsstat status;
+	union {
+		struct diropok diropok;
+	} u;
+};
+
+struct sattrargs {
+	fhandle file;
+	struct sattr attributes;
+};
+
+struct readlinkres {
+	nfsstat status;
+	union {
+		path data;
+	} u;
+};
+
+struct readargs {
+	fhandle file;
+	u32 offset;
+	u32 count;
+	u32 totalcount;
+};
+
+struct readresok {
+	struct fattr attributes;
+	opaque data;
+};
+
+struct readres {
+	nfsstat status;
+	union {
+		struct readresok readresok;
+	} u;
+};
+
+struct writeargs {
+	fhandle file;
+	u32 beginoffset;
+	u32 offset;
+	u32 totalcount;
+	opaque data;
+};
+
+struct createargs {
+	struct diropargs where;
+	struct sattr attributes;
+};
+
+struct renameargs {
+	struct diropargs from;
+	struct diropargs to;
+};
+
+struct linkargs {
+	fhandle from;
+	struct diropargs to;
+};
+
+struct symlinkargs {
+	struct diropargs from;
+	path to;
+	struct sattr attributes;
+};
+
+struct readdirargs {
+	fhandle dir;
+	nfscookie cookie;
+	u32 count;
+};
+
+struct entry {
+	u32 fileid;
+	filename name;
+	nfscookie cookie;
+};
+
+struct readdirok {
+	struct entry *entries;
+	bool eof;
+};
+
+struct readdirres {
+	nfsstat status;
+	union {
+		struct readdirok readdirok;
+	} u;
+};
+
+struct info {
+	u32 tsize;
+	u32 bsize;
+	u32 blocks;
+	u32 bfree;
+	u32 bavail;
+};
+
+struct statfsres {
+	nfsstat status;
+	union {
+		struct info info;
+	} u;
+};
+
+enum {
+	NFSPROC_NULL = 0,
+	NFSPROC_GETATTR = 1,
+	NFSPROC_SETATTR = 2,
+	NFSPROC_ROOT = 3,
+	NFSPROC_LOOKUP = 4,
+	NFSPROC_READLINK = 5,
+	NFSPROC_READ = 6,
+	NFSPROC_WRITECACHE = 7,
+	NFSPROC_WRITE = 8,
+	NFSPROC_CREATE = 9,
+	NFSPROC_REMOVE = 10,
+	NFSPROC_RENAME = 11,
+	NFSPROC_LINK = 12,
+	NFSPROC_SYMLINK = 13,
+	NFSPROC_MKDIR = 14,
+	NFSPROC_RMDIR = 15,
+	NFSPROC_READDIR = 16,
+	NFSPROC_STATFS = 17,
+};
+
+#ifndef NFS_PROGRAM
+#define NFS_PROGRAM (100003)
+#endif
+
+#define NFS2_nfsstat_sz                 (XDR_int)
+#define NFS2_ftype_sz                   (XDR_int)
+#define NFS2_fhandle_sz                 (XDR_QUADLEN(NFS_FHSIZE))
+#define NFS2_nfscookie_sz               (XDR_QUADLEN(NFS_COOKIESIZE))
+#define NFS2_timeval_sz                 \
+	(XDR_unsigned_int + XDR_unsigned_int)
+#define NFS2_fattr_sz                   \
+	(NFS2_ftype_sz + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + NFS2_timeval_sz + NFS2_timeval_sz + NFS2_timeval_sz)
+#define NFS2_sattr_sz                   \
+	(XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + NFS2_timeval_sz + NFS2_timeval_sz)
+#define NFS2_filename_sz                (XDR_unsigned_int + XDR_QUADLEN(NFS_MAXNAMLEN))
+#define NFS2_path_sz                    (XDR_unsigned_int + XDR_QUADLEN(NFS_MAXPATHLEN))
+#define NFS2_attrstat_sz                \
+	(NFS2_nfsstat_sz + NFS2_fattr_sz)
+#define NFS2_diropargs_sz               \
+	(NFS2_fhandle_sz + NFS2_filename_sz)
+#define NFS2_diropok_sz                 \
+	(NFS2_fhandle_sz + NFS2_fattr_sz)
+#define NFS2_diropres_sz                \
+	(NFS2_nfsstat_sz + NFS2_diropok_sz)
+#define NFS2_sattrargs_sz               \
+	(NFS2_fhandle_sz + NFS2_sattr_sz)
+#define NFS2_readlinkres_sz             \
+	(NFS2_nfsstat_sz + NFS2_path_sz)
+#define NFS2_readargs_sz                \
+	(NFS2_fhandle_sz + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int)
+#define NFS2_readresok_sz               \
+	(NFS2_fattr_sz + XDR_unsigned_int + XDR_QUADLEN(NFS_MAXDATA))
+#define NFS2_readres_sz                 \
+	(NFS2_nfsstat_sz + NFS2_readresok_sz)
+#define NFS2_writeargs_sz               \
+	(NFS2_fhandle_sz + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_QUADLEN(NFS_MAXDATA))
+#define NFS2_createargs_sz              \
+	(NFS2_diropargs_sz + NFS2_sattr_sz)
+#define NFS2_renameargs_sz              \
+	(NFS2_diropargs_sz + NFS2_diropargs_sz)
+#define NFS2_linkargs_sz                \
+	(NFS2_fhandle_sz + NFS2_diropargs_sz)
+#define NFS2_symlinkargs_sz             \
+	(NFS2_diropargs_sz + NFS2_path_sz + NFS2_sattr_sz)
+#define NFS2_readdirargs_sz             \
+	(NFS2_fhandle_sz + NFS2_nfscookie_sz + XDR_unsigned_int)
+#define NFS2_entry_sz                   \
+	(XDR_bool + XDR_unsigned_int + NFS2_filename_sz + NFS2_nfscookie_sz)
+#define NFS2_readdirok_sz               \
+	(XDR_bool + XDR_bool)
+#define NFS2_readdirres_sz              \
+	(NFS2_nfsstat_sz + NFS2_readdirok_sz)
+#define NFS2_info_sz                    \
+	(XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int + XDR_unsigned_int)
+#define NFS2_statfsres_sz               \
+	(NFS2_nfsstat_sz + NFS2_info_sz)
+#define NFS2_MAX_ARGS_SZ                \
+	(NFS2_writeargs_sz)
+
+#endif /* _LINUX_XDRGEN_NFS2_DEF_H */