File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
new file mode 100644
index 0000000..3e9f787
--- /dev/null
+++ b/fs/lockd/clntxdr.c
@@ -0,0 +1,621 @@
+/*
+ * linux/fs/lockd/clntxdr.c
+ *
+ * XDR functions to encode/decode NLM version 3 RPC arguments and results.
+ * NLM version 3 is backwards compatible with NLM versions 1 and 2.
+ *
+ * NLM client-side only.
+ *
+ * Copyright (C) 2010, Oracle.  All rights reserved.
+ */
+
+#include <linux/types.h>
+#include <linux/sunrpc/xdr.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/lockd/lockd.h>
+
+#include <uapi/linux/nfs2.h>
+
+#define NLMDBG_FACILITY		NLMDBG_XDR
+
+#if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
+#  error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
+#endif
+
+/*
+ * Declare the space requirements for NLM arguments and replies as
+ * number of 32bit-words
+ */
+#define NLM_cookie_sz		(1+(NLM_MAXCOOKIELEN>>2))
+#define NLM_caller_sz		(1+(NLMCLNT_OHSIZE>>2))
+#define NLM_owner_sz		(1+(NLMCLNT_OHSIZE>>2))
+#define NLM_fhandle_sz		(1+(NFS2_FHSIZE>>2))
+#define NLM_lock_sz		(3+NLM_caller_sz+NLM_owner_sz+NLM_fhandle_sz)
+#define NLM_holder_sz		(4+NLM_owner_sz)
+
+#define NLM_testargs_sz		(NLM_cookie_sz+1+NLM_lock_sz)
+#define NLM_lockargs_sz		(NLM_cookie_sz+4+NLM_lock_sz)
+#define NLM_cancargs_sz		(NLM_cookie_sz+2+NLM_lock_sz)
+#define NLM_unlockargs_sz	(NLM_cookie_sz+NLM_lock_sz)
+
+#define NLM_testres_sz		(NLM_cookie_sz+1+NLM_holder_sz)
+#define NLM_res_sz		(NLM_cookie_sz+1)
+#define NLM_norep_sz		(0)
+
+
+static s32 loff_t_to_s32(loff_t offset)
+{
+	s32 res;
+
+	if (offset >= NLM_OFFSET_MAX)
+		res = NLM_OFFSET_MAX;
+	else if (offset <= -NLM_OFFSET_MAX)
+		res = -NLM_OFFSET_MAX;
+	else
+		res = offset;
+	return res;
+}
+
+static void nlm_compute_offsets(const struct nlm_lock *lock,
+				u32 *l_offset, u32 *l_len)
+{
+	const struct file_lock *fl = &lock->fl;
+
+	*l_offset = loff_t_to_s32(fl->fl_start);
+	if (fl->fl_end == OFFSET_MAX)
+		*l_len = 0;
+	else
+		*l_len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
+}
+
+/*
+ * Handle decode buffer overflows out-of-line.
+ */
+static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
+{
+	dprintk("lockd: %s prematurely hit the end of our receive buffer. "
+		"Remaining buffer length is %tu words.\n",
+		func, xdr->end - xdr->p);
+}
+
+
+/*
+ * Encode/decode NLMv3 basic data types
+ *
+ * Basic NLMv3 data types are not defined in an IETF standards
+ * document.  X/Open has a description of these data types that
+ * is useful.  See Chapter 10 of "Protocols for Interworking:
+ * XNFS, Version 3W".
+ *
+ * Not all basic data types have their own encoding and decoding
+ * functions.  For run-time efficiency, some data types are encoded
+ * or decoded inline.
+ */
+
+static void encode_bool(struct xdr_stream *xdr, const int value)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, 4);
+	*p = value ? xdr_one : xdr_zero;
+}
+
+static void encode_int32(struct xdr_stream *xdr, const s32 value)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, 4);
+	*p = cpu_to_be32(value);
+}
+
+/*
+ *	typedef opaque netobj<MAXNETOBJ_SZ>
+ */
+static void encode_netobj(struct xdr_stream *xdr,
+			  const u8 *data, const unsigned int length)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, 4 + length);
+	xdr_encode_opaque(p, data, length);
+}
+
+static int decode_netobj(struct xdr_stream *xdr,
+			 struct xdr_netobj *obj)
+{
+	u32 length;
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, 4);
+	if (unlikely(p == NULL))
+		goto out_overflow;
+	length = be32_to_cpup(p++);
+	if (unlikely(length > XDR_MAX_NETOBJ))
+		goto out_size;
+	obj->len = length;
+	obj->data = (u8 *)p;
+	return 0;
+out_size:
+	dprintk("NFS: returned netobj was too long: %u\n", length);
+	return -EIO;
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
+
+/*
+ *	netobj cookie;
+ */
+static void encode_cookie(struct xdr_stream *xdr,
+			  const struct nlm_cookie *cookie)
+{
+	encode_netobj(xdr, (u8 *)&cookie->data, cookie->len);
+}
+
+static int decode_cookie(struct xdr_stream *xdr,
+			 struct nlm_cookie *cookie)
+{
+	u32 length;
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, 4);
+	if (unlikely(p == NULL))
+		goto out_overflow;
+	length = be32_to_cpup(p++);
+	/* apparently HPUX can return empty cookies */
+	if (length == 0)
+		goto out_hpux;
+	if (length > NLM_MAXCOOKIELEN)
+		goto out_size;
+	p = xdr_inline_decode(xdr, length);
+	if (unlikely(p == NULL))
+		goto out_overflow;
+	cookie->len = length;
+	memcpy(cookie->data, p, length);
+	return 0;
+out_hpux:
+	cookie->len = 4;
+	memset(cookie->data, 0, 4);
+	return 0;
+out_size:
+	dprintk("NFS: returned cookie was too long: %u\n", length);
+	return -EIO;
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
+
+/*
+ *	netobj fh;
+ */
+static void encode_fh(struct xdr_stream *xdr, const struct nfs_fh *fh)
+{
+	encode_netobj(xdr, (u8 *)&fh->data, NFS2_FHSIZE);
+}
+
+/*
+ *	enum nlm_stats {
+ *		LCK_GRANTED = 0,
+ *		LCK_DENIED = 1,
+ *		LCK_DENIED_NOLOCKS = 2,
+ *		LCK_BLOCKED = 3,
+ *		LCK_DENIED_GRACE_PERIOD = 4
+ *	};
+ *
+ *
+ *	struct nlm_stat {
+ *		nlm_stats stat;
+ *	};
+ *
+ * NB: we don't swap bytes for the NLM status values.  The upper
+ * layers deal directly with the status value in network byte
+ * order.
+ */
+
+static void encode_nlm_stat(struct xdr_stream *xdr,
+			    const __be32 stat)
+{
+	__be32 *p;
+
+	WARN_ON_ONCE(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD);
+	p = xdr_reserve_space(xdr, 4);
+	*p = stat;
+}
+
+static int decode_nlm_stat(struct xdr_stream *xdr,
+			   __be32 *stat)
+{
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, 4);
+	if (unlikely(p == NULL))
+		goto out_overflow;
+	if (unlikely(ntohl(*p) > ntohl(nlm_lck_denied_grace_period)))
+		goto out_enum;
+	*stat = *p;
+	return 0;
+out_enum:
+	dprintk("%s: server returned invalid nlm_stats value: %u\n",
+		__func__, be32_to_cpup(p));
+	return -EIO;
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
+
+/*
+ *	struct nlm_holder {
+ *		bool exclusive;
+ *		int uppid;
+ *		netobj oh;
+ *		unsigned l_offset;
+ *		unsigned l_len;
+ *	};
+ */
+static void encode_nlm_holder(struct xdr_stream *xdr,
+			      const struct nlm_res *result)
+{
+	const struct nlm_lock *lock = &result->lock;
+	u32 l_offset, l_len;
+	__be32 *p;
+
+	encode_bool(xdr, lock->fl.fl_type == F_RDLCK);
+	encode_int32(xdr, lock->svid);
+	encode_netobj(xdr, lock->oh.data, lock->oh.len);
+
+	p = xdr_reserve_space(xdr, 4 + 4);
+	nlm_compute_offsets(lock, &l_offset, &l_len);
+	*p++ = cpu_to_be32(l_offset);
+	*p   = cpu_to_be32(l_len);
+}
+
+static int decode_nlm_holder(struct xdr_stream *xdr, struct nlm_res *result)
+{
+	struct nlm_lock *lock = &result->lock;
+	struct file_lock *fl = &lock->fl;
+	u32 exclusive, l_offset, l_len;
+	int error;
+	__be32 *p;
+	s32 end;
+
+	memset(lock, 0, sizeof(*lock));
+	locks_init_lock(fl);
+
+	p = xdr_inline_decode(xdr, 4 + 4);
+	if (unlikely(p == NULL))
+		goto out_overflow;
+	exclusive = be32_to_cpup(p++);
+	lock->svid = be32_to_cpup(p);
+	fl->fl_pid = (pid_t)lock->svid;
+
+	error = decode_netobj(xdr, &lock->oh);
+	if (unlikely(error))
+		goto out;
+
+	p = xdr_inline_decode(xdr, 4 + 4);
+	if (unlikely(p == NULL))
+		goto out_overflow;
+
+	fl->fl_flags = FL_POSIX;
+	fl->fl_type  = exclusive != 0 ? F_WRLCK : F_RDLCK;
+	l_offset = be32_to_cpup(p++);
+	l_len = be32_to_cpup(p);
+	end = l_offset + l_len - 1;
+
+	fl->fl_start = (loff_t)l_offset;
+	if (l_len == 0 || end < 0)
+		fl->fl_end = OFFSET_MAX;
+	else
+		fl->fl_end = (loff_t)end;
+	error = 0;
+out:
+	return error;
+out_overflow:
+	print_overflow_msg(__func__, xdr);
+	return -EIO;
+}
+
+/*
+ *	string caller_name<LM_MAXSTRLEN>;
+ */
+static void encode_caller_name(struct xdr_stream *xdr, const char *name)
+{
+	/* NB: client-side does not set lock->len */
+	u32 length = strlen(name);
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, 4 + length);
+	xdr_encode_opaque(p, name, length);
+}
+
+/*
+ *	struct nlm_lock {
+ *		string caller_name<LM_MAXSTRLEN>;
+ *		netobj fh;
+ *		netobj oh;
+ *		int uppid;
+ *		unsigned l_offset;
+ *		unsigned l_len;
+ *	};
+ */
+static void encode_nlm_lock(struct xdr_stream *xdr,
+			    const struct nlm_lock *lock)
+{
+	u32 l_offset, l_len;
+	__be32 *p;
+
+	encode_caller_name(xdr, lock->caller);
+	encode_fh(xdr, &lock->fh);
+	encode_netobj(xdr, lock->oh.data, lock->oh.len);
+
+	p = xdr_reserve_space(xdr, 4 + 4 + 4);
+	*p++ = cpu_to_be32(lock->svid);
+
+	nlm_compute_offsets(lock, &l_offset, &l_len);
+	*p++ = cpu_to_be32(l_offset);
+	*p   = cpu_to_be32(l_len);
+}
+
+
+/*
+ * NLMv3 XDR encode functions
+ *
+ * NLMv3 argument types are defined in Chapter 10 of The Open Group's
+ * "Protocols for Interworking: XNFS, Version 3W".
+ */
+
+/*
+ *	struct nlm_testargs {
+ *		netobj cookie;
+ *		bool exclusive;
+ *		struct nlm_lock alock;
+ *	};
+ */
+static void nlm_xdr_enc_testargs(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_args *args)
+{
+	const struct nlm_lock *lock = &args->lock;
+
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm_lock(xdr, lock);
+}
+
+/*
+ *	struct nlm_lockargs {
+ *		netobj cookie;
+ *		bool block;
+ *		bool exclusive;
+ *		struct nlm_lock alock;
+ *		bool reclaim;
+ *		int state;
+ *	};
+ */
+static void nlm_xdr_enc_lockargs(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_args *args)
+{
+	const struct nlm_lock *lock = &args->lock;
+
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, args->block);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm_lock(xdr, lock);
+	encode_bool(xdr, args->reclaim);
+	encode_int32(xdr, args->state);
+}
+
+/*
+ *	struct nlm_cancargs {
+ *		netobj cookie;
+ *		bool block;
+ *		bool exclusive;
+ *		struct nlm_lock alock;
+ *	};
+ */
+static void nlm_xdr_enc_cancargs(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_args *args)
+{
+	const struct nlm_lock *lock = &args->lock;
+
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, args->block);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm_lock(xdr, lock);
+}
+
+/*
+ *	struct nlm_unlockargs {
+ *		netobj cookie;
+ *		struct nlm_lock alock;
+ *	};
+ */
+static void nlm_xdr_enc_unlockargs(struct rpc_rqst *req,
+				   struct xdr_stream *xdr,
+				   const struct nlm_args *args)
+{
+	const struct nlm_lock *lock = &args->lock;
+
+	encode_cookie(xdr, &args->cookie);
+	encode_nlm_lock(xdr, lock);
+}
+
+/*
+ *	struct nlm_res {
+ *		netobj cookie;
+ *		nlm_stat stat;
+ *	};
+ */
+static void nlm_xdr_enc_res(struct rpc_rqst *req,
+			    struct xdr_stream *xdr,
+			    const struct nlm_res *result)
+{
+	encode_cookie(xdr, &result->cookie);
+	encode_nlm_stat(xdr, result->status);
+}
+
+/*
+ *	union nlm_testrply switch (nlm_stats stat) {
+ *	case LCK_DENIED:
+ *		struct nlm_holder holder;
+ *	default:
+ *		void;
+ *	};
+ *
+ *	struct nlm_testres {
+ *		netobj cookie;
+ *		nlm_testrply test_stat;
+ *	};
+ */
+static void encode_nlm_testrply(struct xdr_stream *xdr,
+				const struct nlm_res *result)
+{
+	if (result->status == nlm_lck_denied)
+		encode_nlm_holder(xdr, result);
+}
+
+static void nlm_xdr_enc_testres(struct rpc_rqst *req,
+				struct xdr_stream *xdr,
+				const struct nlm_res *result)
+{
+	encode_cookie(xdr, &result->cookie);
+	encode_nlm_stat(xdr, result->status);
+	encode_nlm_testrply(xdr, result);
+}
+
+
+/*
+ * NLMv3 XDR decode functions
+ *
+ * NLMv3 result types are defined in Chapter 10 of The Open Group's
+ * "Protocols for Interworking: XNFS, Version 3W".
+ */
+
+/*
+ *	union nlm_testrply switch (nlm_stats stat) {
+ *	case LCK_DENIED:
+ *		struct nlm_holder holder;
+ *	default:
+ *		void;
+ *	};
+ *
+ *	struct nlm_testres {
+ *		netobj cookie;
+ *		nlm_testrply test_stat;
+ *	};
+ */
+static int decode_nlm_testrply(struct xdr_stream *xdr,
+			       struct nlm_res *result)
+{
+	int error;
+
+	error = decode_nlm_stat(xdr, &result->status);
+	if (unlikely(error))
+		goto out;
+	if (result->status == nlm_lck_denied)
+		error = decode_nlm_holder(xdr, result);
+out:
+	return error;
+}
+
+static int nlm_xdr_dec_testres(struct rpc_rqst *req,
+			       struct xdr_stream *xdr,
+			       struct nlm_res *result)
+{
+	int error;
+
+	error = decode_cookie(xdr, &result->cookie);
+	if (unlikely(error))
+		goto out;
+	error = decode_nlm_testrply(xdr, result);
+out:
+	return error;
+}
+
+/*
+ *	struct nlm_res {
+ *		netobj cookie;
+ *		nlm_stat stat;
+ *	};
+ */
+static int nlm_xdr_dec_res(struct rpc_rqst *req,
+			   struct xdr_stream *xdr,
+			   struct nlm_res *result)
+{
+	int error;
+
+	error = decode_cookie(xdr, &result->cookie);
+	if (unlikely(error))
+		goto out;
+	error = decode_nlm_stat(xdr, &result->status);
+out:
+	return error;
+}
+
+
+/*
+ * For NLM, a void procedure really returns nothing
+ */
+#define nlm_xdr_dec_norep	NULL
+
+#define PROC(proc, argtype, restype)	\
+[NLMPROC_##proc] = {							\
+	.p_proc      = NLMPROC_##proc,					\
+	.p_encode    = (kxdreproc_t)nlm_xdr_enc_##argtype,		\
+	.p_decode    = (kxdrdproc_t)nlm_xdr_dec_##restype,		\
+	.p_arglen    = NLM_##argtype##_sz,				\
+	.p_replen    = NLM_##restype##_sz,				\
+	.p_statidx   = NLMPROC_##proc,					\
+	.p_name      = #proc,						\
+	}
+
+static struct rpc_procinfo	nlm_procedures[] = {
+	PROC(TEST,		testargs,	testres),
+	PROC(LOCK,		lockargs,	res),
+	PROC(CANCEL,		cancargs,	res),
+	PROC(UNLOCK,		unlockargs,	res),
+	PROC(GRANTED,		testargs,	res),
+	PROC(TEST_MSG,		testargs,	norep),
+	PROC(LOCK_MSG,		lockargs,	norep),
+	PROC(CANCEL_MSG,	cancargs,	norep),
+	PROC(UNLOCK_MSG,	unlockargs,	norep),
+	PROC(GRANTED_MSG,	testargs,	norep),
+	PROC(TEST_RES,		testres,	norep),
+	PROC(LOCK_RES,		res,		norep),
+	PROC(CANCEL_RES,	res,		norep),
+	PROC(UNLOCK_RES,	res,		norep),
+	PROC(GRANTED_RES,	res,		norep),
+};
+
+static const struct rpc_version	nlm_version1 = {
+		.number		= 1,
+		.nrprocs	= ARRAY_SIZE(nlm_procedures),
+		.procs		= nlm_procedures,
+};
+
+static const struct rpc_version	nlm_version3 = {
+		.number		= 3,
+		.nrprocs	= ARRAY_SIZE(nlm_procedures),
+		.procs		= nlm_procedures,
+};
+
+static const struct rpc_version	*nlm_versions[] = {
+	[1] = &nlm_version1,
+	[3] = &nlm_version3,
+#ifdef CONFIG_LOCKD_V4
+	[4] = &nlm_version4,
+#endif
+};
+
+static struct rpc_stat		nlm_rpc_stats;
+
+const struct rpc_program	nlm_program = {
+		.name		= "lockd",
+		.number		= NLM_PROGRAM,
+		.nrvers		= ARRAY_SIZE(nlm_versions),
+		.version	= nlm_versions,
+		.stats		= &nlm_rpc_stats,
+};