cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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svc.h (18781B)


      1/* SPDX-License-Identifier: GPL-2.0 */
      2/*
      3 * linux/include/linux/sunrpc/svc.h
      4 *
      5 * RPC server declarations.
      6 *
      7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
      8 */
      9
     10
     11#ifndef SUNRPC_SVC_H
     12#define SUNRPC_SVC_H
     13
     14#include <linux/in.h>
     15#include <linux/in6.h>
     16#include <linux/sunrpc/types.h>
     17#include <linux/sunrpc/xdr.h>
     18#include <linux/sunrpc/auth.h>
     19#include <linux/sunrpc/svcauth.h>
     20#include <linux/wait.h>
     21#include <linux/mm.h>
     22#include <linux/pagevec.h>
     23
     24/* statistics for svc_pool structures */
     25struct svc_pool_stats {
     26	atomic_long_t	packets;
     27	unsigned long	sockets_queued;
     28	atomic_long_t	threads_woken;
     29	atomic_long_t	threads_timedout;
     30};
     31
     32/*
     33 *
     34 * RPC service thread pool.
     35 *
     36 * Pool of threads and temporary sockets.  Generally there is only
     37 * a single one of these per RPC service, but on NUMA machines those
     38 * services that can benefit from it (i.e. nfs but not lockd) will
     39 * have one pool per NUMA node.  This optimisation reduces cross-
     40 * node traffic on multi-node NUMA NFS servers.
     41 */
     42struct svc_pool {
     43	unsigned int		sp_id;	    	/* pool id; also node id on NUMA */
     44	spinlock_t		sp_lock;	/* protects all fields */
     45	struct list_head	sp_sockets;	/* pending sockets */
     46	unsigned int		sp_nrthreads;	/* # of threads in pool */
     47	struct list_head	sp_all_threads;	/* all server threads */
     48	struct svc_pool_stats	sp_stats;	/* statistics on pool operation */
     49#define	SP_TASK_PENDING		(0)		/* still work to do even if no
     50						 * xprt is queued. */
     51#define SP_CONGESTED		(1)
     52	unsigned long		sp_flags;
     53} ____cacheline_aligned_in_smp;
     54
     55/*
     56 * RPC service.
     57 *
     58 * An RPC service is a ``daemon,'' possibly multithreaded, which
     59 * receives and processes incoming RPC messages.
     60 * It has one or more transport sockets associated with it, and maintains
     61 * a list of idle threads waiting for input.
     62 *
     63 * We currently do not support more than one RPC program per daemon.
     64 */
     65struct svc_serv {
     66	struct svc_program *	sv_program;	/* RPC program */
     67	struct svc_stat *	sv_stats;	/* RPC statistics */
     68	spinlock_t		sv_lock;
     69	struct kref		sv_refcnt;
     70	unsigned int		sv_nrthreads;	/* # of server threads */
     71	unsigned int		sv_maxconn;	/* max connections allowed or
     72						 * '0' causing max to be based
     73						 * on number of threads. */
     74
     75	unsigned int		sv_max_payload;	/* datagram payload size */
     76	unsigned int		sv_max_mesg;	/* max_payload + 1 page for overheads */
     77	unsigned int		sv_xdrsize;	/* XDR buffer size */
     78	struct list_head	sv_permsocks;	/* all permanent sockets */
     79	struct list_head	sv_tempsocks;	/* all temporary sockets */
     80	int			sv_tmpcnt;	/* count of temporary sockets */
     81	struct timer_list	sv_temptimer;	/* timer for aging temporary sockets */
     82
     83	char *			sv_name;	/* service name */
     84
     85	unsigned int		sv_nrpools;	/* number of thread pools */
     86	struct svc_pool *	sv_pools;	/* array of thread pools */
     87	int			(*sv_threadfn)(void *data);
     88
     89#if defined(CONFIG_SUNRPC_BACKCHANNEL)
     90	struct list_head	sv_cb_list;	/* queue for callback requests
     91						 * that arrive over the same
     92						 * connection */
     93	spinlock_t		sv_cb_lock;	/* protects the svc_cb_list */
     94	wait_queue_head_t	sv_cb_waitq;	/* sleep here if there are no
     95						 * entries in the svc_cb_list */
     96	bool			sv_bc_enabled;	/* service uses backchannel */
     97#endif /* CONFIG_SUNRPC_BACKCHANNEL */
     98};
     99
    100/**
    101 * svc_get() - increment reference count on a SUNRPC serv
    102 * @serv:  the svc_serv to have count incremented
    103 *
    104 * Returns: the svc_serv that was passed in.
    105 */
    106static inline struct svc_serv *svc_get(struct svc_serv *serv)
    107{
    108	kref_get(&serv->sv_refcnt);
    109	return serv;
    110}
    111
    112void svc_destroy(struct kref *);
    113
    114/**
    115 * svc_put - decrement reference count on a SUNRPC serv
    116 * @serv:  the svc_serv to have count decremented
    117 *
    118 * When the reference count reaches zero, svc_destroy()
    119 * is called to clean up and free the serv.
    120 */
    121static inline void svc_put(struct svc_serv *serv)
    122{
    123	kref_put(&serv->sv_refcnt, svc_destroy);
    124}
    125
    126/**
    127 * svc_put_not_last - decrement non-final reference count on SUNRPC serv
    128 * @serv:  the svc_serv to have count decremented
    129 *
    130 * Returns: %true is refcount was decremented.
    131 *
    132 * If the refcount is 1, it is not decremented and instead failure is reported.
    133 */
    134static inline bool svc_put_not_last(struct svc_serv *serv)
    135{
    136	return refcount_dec_not_one(&serv->sv_refcnt.refcount);
    137}
    138
    139/*
    140 * Maximum payload size supported by a kernel RPC server.
    141 * This is use to determine the max number of pages nfsd is
    142 * willing to return in a single READ operation.
    143 *
    144 * These happen to all be powers of 2, which is not strictly
    145 * necessary but helps enforce the real limitation, which is
    146 * that they should be multiples of PAGE_SIZE.
    147 *
    148 * For UDP transports, a block plus NFS,RPC, and UDP headers
    149 * has to fit into the IP datagram limit of 64K.  The largest
    150 * feasible number for all known page sizes is probably 48K,
    151 * but we choose 32K here.  This is the same as the historical
    152 * Linux limit; someone who cares more about NFS/UDP performance
    153 * can test a larger number.
    154 *
    155 * For TCP transports we have more freedom.  A size of 1MB is
    156 * chosen to match the client limit.  Other OSes are known to
    157 * have larger limits, but those numbers are probably beyond
    158 * the point of diminishing returns.
    159 */
    160#define RPCSVC_MAXPAYLOAD	(1*1024*1024u)
    161#define RPCSVC_MAXPAYLOAD_TCP	RPCSVC_MAXPAYLOAD
    162#define RPCSVC_MAXPAYLOAD_UDP	(32*1024u)
    163
    164extern u32 svc_max_payload(const struct svc_rqst *rqstp);
    165
    166/*
    167 * RPC Requsts and replies are stored in one or more pages.
    168 * We maintain an array of pages for each server thread.
    169 * Requests are copied into these pages as they arrive.  Remaining
    170 * pages are available to write the reply into.
    171 *
    172 * Pages are sent using ->sendpage so each server thread needs to
    173 * allocate more to replace those used in sending.  To help keep track
    174 * of these pages we have a receive list where all pages initialy live,
    175 * and a send list where pages are moved to when there are to be part
    176 * of a reply.
    177 *
    178 * We use xdr_buf for holding responses as it fits well with NFS
    179 * read responses (that have a header, and some data pages, and possibly
    180 * a tail) and means we can share some client side routines.
    181 *
    182 * The xdr_buf.head kvec always points to the first page in the rq_*pages
    183 * list.  The xdr_buf.pages pointer points to the second page on that
    184 * list.  xdr_buf.tail points to the end of the first page.
    185 * This assumes that the non-page part of an rpc reply will fit
    186 * in a page - NFSd ensures this.  lockd also has no trouble.
    187 *
    188 * Each request/reply pair can have at most one "payload", plus two pages,
    189 * one for the request, and one for the reply.
    190 * We using ->sendfile to return read data, we might need one extra page
    191 * if the request is not page-aligned.  So add another '1'.
    192 */
    193#define RPCSVC_MAXPAGES		((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \
    194				+ 2 + 1)
    195
    196static inline u32 svc_getnl(struct kvec *iov)
    197{
    198	__be32 val, *vp;
    199	vp = iov->iov_base;
    200	val = *vp++;
    201	iov->iov_base = (void*)vp;
    202	iov->iov_len -= sizeof(__be32);
    203	return ntohl(val);
    204}
    205
    206static inline void svc_putnl(struct kvec *iov, u32 val)
    207{
    208	__be32 *vp = iov->iov_base + iov->iov_len;
    209	*vp = htonl(val);
    210	iov->iov_len += sizeof(__be32);
    211}
    212
    213static inline __be32 svc_getu32(struct kvec *iov)
    214{
    215	__be32 val, *vp;
    216	vp = iov->iov_base;
    217	val = *vp++;
    218	iov->iov_base = (void*)vp;
    219	iov->iov_len -= sizeof(__be32);
    220	return val;
    221}
    222
    223static inline void svc_ungetu32(struct kvec *iov)
    224{
    225	__be32 *vp = (__be32 *)iov->iov_base;
    226	iov->iov_base = (void *)(vp - 1);
    227	iov->iov_len += sizeof(*vp);
    228}
    229
    230static inline void svc_putu32(struct kvec *iov, __be32 val)
    231{
    232	__be32 *vp = iov->iov_base + iov->iov_len;
    233	*vp = val;
    234	iov->iov_len += sizeof(__be32);
    235}
    236
    237/*
    238 * The context of a single thread, including the request currently being
    239 * processed.
    240 */
    241struct svc_rqst {
    242	struct list_head	rq_all;		/* all threads list */
    243	struct rcu_head		rq_rcu_head;	/* for RCU deferred kfree */
    244	struct svc_xprt *	rq_xprt;	/* transport ptr */
    245
    246	struct sockaddr_storage	rq_addr;	/* peer address */
    247	size_t			rq_addrlen;
    248	struct sockaddr_storage	rq_daddr;	/* dest addr of request
    249						 *  - reply from here */
    250	size_t			rq_daddrlen;
    251
    252	struct svc_serv *	rq_server;	/* RPC service definition */
    253	struct svc_pool *	rq_pool;	/* thread pool */
    254	const struct svc_procedure *rq_procinfo;/* procedure info */
    255	struct auth_ops *	rq_authop;	/* authentication flavour */
    256	struct svc_cred		rq_cred;	/* auth info */
    257	void *			rq_xprt_ctxt;	/* transport specific context ptr */
    258	struct svc_deferred_req*rq_deferred;	/* deferred request we are replaying */
    259
    260	struct xdr_buf		rq_arg;
    261	struct xdr_stream	rq_arg_stream;
    262	struct xdr_stream	rq_res_stream;
    263	struct page		*rq_scratch_page;
    264	struct xdr_buf		rq_res;
    265	struct page		*rq_pages[RPCSVC_MAXPAGES + 1];
    266	struct page *		*rq_respages;	/* points into rq_pages */
    267	struct page *		*rq_next_page; /* next reply page to use */
    268	struct page *		*rq_page_end;  /* one past the last page */
    269
    270	struct pagevec		rq_pvec;
    271	struct kvec		rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */
    272	struct bio_vec		rq_bvec[RPCSVC_MAXPAGES];
    273
    274	__be32			rq_xid;		/* transmission id */
    275	u32			rq_prog;	/* program number */
    276	u32			rq_vers;	/* program version */
    277	u32			rq_proc;	/* procedure number */
    278	u32			rq_prot;	/* IP protocol */
    279	int			rq_cachetype;	/* catering to nfsd */
    280#define	RQ_SECURE	(0)			/* secure port */
    281#define	RQ_LOCAL	(1)			/* local request */
    282#define	RQ_USEDEFERRAL	(2)			/* use deferral */
    283#define	RQ_DROPME	(3)			/* drop current reply */
    284#define	RQ_SPLICE_OK	(4)			/* turned off in gss privacy
    285						 * to prevent encrypting page
    286						 * cache pages */
    287#define	RQ_VICTIM	(5)			/* about to be shut down */
    288#define	RQ_BUSY		(6)			/* request is busy */
    289#define	RQ_DATA		(7)			/* request has data */
    290	unsigned long		rq_flags;	/* flags field */
    291	ktime_t			rq_qtime;	/* enqueue time */
    292
    293	void *			rq_argp;	/* decoded arguments */
    294	void *			rq_resp;	/* xdr'd results */
    295	void *			rq_auth_data;	/* flavor-specific data */
    296	__be32			rq_auth_stat;	/* authentication status */
    297	int			rq_auth_slack;	/* extra space xdr code
    298						 * should leave in head
    299						 * for krb5i, krb5p.
    300						 */
    301	int			rq_reserved;	/* space on socket outq
    302						 * reserved for this request
    303						 */
    304	ktime_t			rq_stime;	/* start time */
    305
    306	struct cache_req	rq_chandle;	/* handle passed to caches for 
    307						 * request delaying 
    308						 */
    309	/* Catering to nfsd */
    310	struct auth_domain *	rq_client;	/* RPC peer info */
    311	struct auth_domain *	rq_gssclient;	/* "gss/"-style peer info */
    312	struct svc_cacherep *	rq_cacherep;	/* cache info */
    313	struct task_struct	*rq_task;	/* service thread */
    314	spinlock_t		rq_lock;	/* per-request lock */
    315	struct net		*rq_bc_net;	/* pointer to backchannel's
    316						 * net namespace
    317						 */
    318	void **			rq_lease_breaker; /* The v4 client breaking a lease */
    319};
    320
    321#define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net)
    322
    323/*
    324 * Rigorous type checking on sockaddr type conversions
    325 */
    326static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst)
    327{
    328	return (struct sockaddr_in *) &rqst->rq_addr;
    329}
    330
    331static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst)
    332{
    333	return (struct sockaddr_in6 *) &rqst->rq_addr;
    334}
    335
    336static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst)
    337{
    338	return (struct sockaddr *) &rqst->rq_addr;
    339}
    340
    341static inline struct sockaddr_in *svc_daddr_in(const struct svc_rqst *rqst)
    342{
    343	return (struct sockaddr_in *) &rqst->rq_daddr;
    344}
    345
    346static inline struct sockaddr_in6 *svc_daddr_in6(const struct svc_rqst *rqst)
    347{
    348	return (struct sockaddr_in6 *) &rqst->rq_daddr;
    349}
    350
    351static inline struct sockaddr *svc_daddr(const struct svc_rqst *rqst)
    352{
    353	return (struct sockaddr *) &rqst->rq_daddr;
    354}
    355
    356/*
    357 * Check buffer bounds after decoding arguments
    358 */
    359static inline int
    360xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p)
    361{
    362	char *cp = (char *)p;
    363	struct kvec *vec = &rqstp->rq_arg.head[0];
    364	return cp >= (char*)vec->iov_base
    365		&& cp <= (char*)vec->iov_base + vec->iov_len;
    366}
    367
    368static inline int
    369xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p)
    370{
    371	struct kvec *vec = &rqstp->rq_res.head[0];
    372	char *cp = (char*)p;
    373
    374	vec->iov_len = cp - (char*)vec->iov_base;
    375
    376	return vec->iov_len <= PAGE_SIZE;
    377}
    378
    379static inline void svc_free_res_pages(struct svc_rqst *rqstp)
    380{
    381	while (rqstp->rq_next_page != rqstp->rq_respages) {
    382		struct page **pp = --rqstp->rq_next_page;
    383		if (*pp) {
    384			put_page(*pp);
    385			*pp = NULL;
    386		}
    387	}
    388}
    389
    390struct svc_deferred_req {
    391	u32			prot;	/* protocol (UDP or TCP) */
    392	struct svc_xprt		*xprt;
    393	struct sockaddr_storage	addr;	/* where reply must go */
    394	size_t			addrlen;
    395	struct sockaddr_storage	daddr;	/* where reply must come from */
    396	size_t			daddrlen;
    397	void			*xprt_ctxt;
    398	struct cache_deferred_req handle;
    399	int			argslen;
    400	__be32			args[];
    401};
    402
    403struct svc_process_info {
    404	union {
    405		int  (*dispatch)(struct svc_rqst *, __be32 *);
    406		struct {
    407			unsigned int lovers;
    408			unsigned int hivers;
    409		} mismatch;
    410	};
    411};
    412
    413/*
    414 * List of RPC programs on the same transport endpoint
    415 */
    416struct svc_program {
    417	struct svc_program *	pg_next;	/* other programs (same xprt) */
    418	u32			pg_prog;	/* program number */
    419	unsigned int		pg_lovers;	/* lowest version */
    420	unsigned int		pg_hivers;	/* highest version */
    421	unsigned int		pg_nvers;	/* number of versions */
    422	const struct svc_version **pg_vers;	/* version array */
    423	char *			pg_name;	/* service name */
    424	char *			pg_class;	/* class name: services sharing authentication */
    425	struct svc_stat *	pg_stats;	/* rpc statistics */
    426	int			(*pg_authenticate)(struct svc_rqst *);
    427	__be32			(*pg_init_request)(struct svc_rqst *,
    428						   const struct svc_program *,
    429						   struct svc_process_info *);
    430	int			(*pg_rpcbind_set)(struct net *net,
    431						  const struct svc_program *,
    432						  u32 version, int family,
    433						  unsigned short proto,
    434						  unsigned short port);
    435};
    436
    437/*
    438 * RPC program version
    439 */
    440struct svc_version {
    441	u32			vs_vers;	/* version number */
    442	u32			vs_nproc;	/* number of procedures */
    443	const struct svc_procedure *vs_proc;	/* per-procedure info */
    444	unsigned int		*vs_count;	/* call counts */
    445	u32			vs_xdrsize;	/* xdrsize needed for this version */
    446
    447	/* Don't register with rpcbind */
    448	bool			vs_hidden;
    449
    450	/* Don't care if the rpcbind registration fails */
    451	bool			vs_rpcb_optnl;
    452
    453	/* Need xprt with congestion control */
    454	bool			vs_need_cong_ctrl;
    455
    456	/* Dispatch function */
    457	int			(*vs_dispatch)(struct svc_rqst *, __be32 *);
    458};
    459
    460/*
    461 * RPC procedure info
    462 */
    463struct svc_procedure {
    464	/* process the request: */
    465	__be32			(*pc_func)(struct svc_rqst *);
    466	/* XDR decode args: */
    467	bool			(*pc_decode)(struct svc_rqst *rqstp,
    468					     struct xdr_stream *xdr);
    469	/* XDR encode result: */
    470	bool			(*pc_encode)(struct svc_rqst *rqstp,
    471					     struct xdr_stream *xdr);
    472	/* XDR free result: */
    473	void			(*pc_release)(struct svc_rqst *);
    474	unsigned int		pc_argsize;	/* argument struct size */
    475	unsigned int		pc_ressize;	/* result struct size */
    476	unsigned int		pc_cachetype;	/* cache info (NFS) */
    477	unsigned int		pc_xdrressize;	/* maximum size of XDR reply */
    478	const char *		pc_name;	/* for display */
    479};
    480
    481/*
    482 * Function prototypes.
    483 */
    484int svc_rpcb_setup(struct svc_serv *serv, struct net *net);
    485void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net);
    486int svc_bind(struct svc_serv *serv, struct net *net);
    487struct svc_serv *svc_create(struct svc_program *, unsigned int,
    488			    int (*threadfn)(void *data));
    489struct svc_rqst *svc_rqst_alloc(struct svc_serv *serv,
    490					struct svc_pool *pool, int node);
    491void		   svc_rqst_replace_page(struct svc_rqst *rqstp,
    492					 struct page *page);
    493void		   svc_rqst_free(struct svc_rqst *);
    494void		   svc_exit_thread(struct svc_rqst *);
    495struct svc_serv *  svc_create_pooled(struct svc_program *, unsigned int,
    496				     int (*threadfn)(void *data));
    497int		   svc_set_num_threads(struct svc_serv *, struct svc_pool *, int);
    498int		   svc_pool_stats_open(struct svc_serv *serv, struct file *file);
    499int		   svc_process(struct svc_rqst *);
    500int		   bc_svc_process(struct svc_serv *, struct rpc_rqst *,
    501			struct svc_rqst *);
    502int		   svc_register(const struct svc_serv *, struct net *, const int,
    503				const unsigned short, const unsigned short);
    504
    505void		   svc_wake_up(struct svc_serv *);
    506void		   svc_reserve(struct svc_rqst *rqstp, int space);
    507struct svc_pool   *svc_pool_for_cpu(struct svc_serv *serv);
    508char *		   svc_print_addr(struct svc_rqst *, char *, size_t);
    509const char *	   svc_proc_name(const struct svc_rqst *rqstp);
    510int		   svc_encode_result_payload(struct svc_rqst *rqstp,
    511					     unsigned int offset,
    512					     unsigned int length);
    513unsigned int	   svc_fill_write_vector(struct svc_rqst *rqstp,
    514					 struct xdr_buf *payload);
    515char		  *svc_fill_symlink_pathname(struct svc_rqst *rqstp,
    516					     struct kvec *first, void *p,
    517					     size_t total);
    518__be32		   svc_generic_init_request(struct svc_rqst *rqstp,
    519					    const struct svc_program *progp,
    520					    struct svc_process_info *procinfo);
    521int		   svc_generic_rpcbind_set(struct net *net,
    522					   const struct svc_program *progp,
    523					   u32 version, int family,
    524					   unsigned short proto,
    525					   unsigned short port);
    526int		   svc_rpcbind_set_version(struct net *net,
    527					   const struct svc_program *progp,
    528					   u32 version, int family,
    529					   unsigned short proto,
    530					   unsigned short port);
    531
    532#define	RPC_MAX_ADDRBUFLEN	(63U)
    533
    534/*
    535 * When we want to reduce the size of the reserved space in the response
    536 * buffer, we need to take into account the size of any checksum data that
    537 * may be at the end of the packet. This is difficult to determine exactly
    538 * for all cases without actually generating the checksum, so we just use a
    539 * static value.
    540 */
    541static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space)
    542{
    543	svc_reserve(rqstp, space + rqstp->rq_auth_slack);
    544}
    545
    546/**
    547 * svcxdr_init_decode - Prepare an xdr_stream for svc Call decoding
    548 * @rqstp: controlling server RPC transaction context
    549 *
    550 */
    551static inline void svcxdr_init_decode(struct svc_rqst *rqstp)
    552{
    553	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
    554	struct kvec *argv = rqstp->rq_arg.head;
    555
    556	xdr_init_decode(xdr, &rqstp->rq_arg, argv->iov_base, NULL);
    557	xdr_set_scratch_page(xdr, rqstp->rq_scratch_page);
    558}
    559
    560/**
    561 * svcxdr_init_encode - Prepare an xdr_stream for svc Reply encoding
    562 * @rqstp: controlling server RPC transaction context
    563 *
    564 */
    565static inline void svcxdr_init_encode(struct svc_rqst *rqstp)
    566{
    567	struct xdr_stream *xdr = &rqstp->rq_res_stream;
    568	struct xdr_buf *buf = &rqstp->rq_res;
    569	struct kvec *resv = buf->head;
    570
    571	xdr_reset_scratch_buffer(xdr);
    572
    573	xdr->buf = buf;
    574	xdr->iov = resv;
    575	xdr->p   = resv->iov_base + resv->iov_len;
    576	xdr->end = resv->iov_base + PAGE_SIZE - rqstp->rq_auth_slack;
    577	buf->len = resv->iov_len;
    578	xdr->page_ptr = buf->pages - 1;
    579	buf->buflen = PAGE_SIZE * (1 + rqstp->rq_page_end - buf->pages);
    580	buf->buflen -= rqstp->rq_auth_slack;
    581	xdr->rqst = NULL;
    582}
    583
    584#endif /* SUNRPC_SVC_H */