/* SPDX-License-Identifier: GPL-2.0 */ /* * linux/include/linux/sunrpc/svc.h * * RPC server declarations. * * Copyright (C) 1995, 1996 Olaf Kirch */ #ifndef SUNRPC_SVC_H #define SUNRPC_SVC_H #include #include #include #include #include #include #include #include /* statistics for svc_pool structures */ struct svc_pool_stats { atomic_long_t packets; unsigned long sockets_queued; atomic_long_t threads_woken; atomic_long_t threads_timedout; }; /* * * RPC service thread pool. * * Pool of threads and temporary sockets. Generally there is only * a single one of these per RPC service, but on NUMA machines those * services that can benefit from it (i.e. nfs but not lockd) will * have one pool per NUMA node. This optimisation reduces cross- * node traffic on multi-node NUMA NFS servers. */ struct svc_pool { unsigned int sp_id; /* pool id; also node id on NUMA */ spinlock_t sp_lock; /* protects all fields */ struct list_head sp_sockets; /* pending sockets */ unsigned int sp_nrthreads; /* # of threads in pool */ struct list_head sp_all_threads; /* all server threads */ struct svc_pool_stats sp_stats; /* statistics on pool operation */ #define SP_TASK_PENDING (0) /* still work to do even if no * xprt is queued. */ #define SP_CONGESTED (1) unsigned long sp_flags; } ____cacheline_aligned_in_smp; struct svc_serv; struct svc_serv_ops { /* Callback to use when last thread exits. */ void (*svo_shutdown)(struct svc_serv *, struct net *); /* function for service threads to run */ int (*svo_function)(void *); /* queue up a transport for servicing */ void (*svo_enqueue_xprt)(struct svc_xprt *); /* set up thread (or whatever) execution context */ int (*svo_setup)(struct svc_serv *, struct svc_pool *, int); /* optional module to count when adding threads (pooled svcs only) */ struct module *svo_module; }; /* * RPC service. * * An RPC service is a ``daemon,'' possibly multithreaded, which * receives and processes incoming RPC messages. * It has one or more transport sockets associated with it, and maintains * a list of idle threads waiting for input. * * We currently do not support more than one RPC program per daemon. */ struct svc_serv { struct svc_program * sv_program; /* RPC program */ struct svc_stat * sv_stats; /* RPC statistics */ spinlock_t sv_lock; unsigned int sv_nrthreads; /* # of server threads */ unsigned int sv_maxconn; /* max connections allowed or * '0' causing max to be based * on number of threads. */ unsigned int sv_max_payload; /* datagram payload size */ unsigned int sv_max_mesg; /* max_payload + 1 page for overheads */ unsigned int sv_xdrsize; /* XDR buffer size */ struct list_head sv_permsocks; /* all permanent sockets */ struct list_head sv_tempsocks; /* all temporary sockets */ int sv_tmpcnt; /* count of temporary sockets */ struct timer_list sv_temptimer; /* timer for aging temporary sockets */ char * sv_name; /* service name */ unsigned int sv_nrpools; /* number of thread pools */ struct svc_pool * sv_pools; /* array of thread pools */ const struct svc_serv_ops *sv_ops; /* server operations */ #if defined(CONFIG_SUNRPC_BACKCHANNEL) struct list_head sv_cb_list; /* queue for callback requests * that arrive over the same * connection */ spinlock_t sv_cb_lock; /* protects the svc_cb_list */ wait_queue_head_t sv_cb_waitq; /* sleep here if there are no * entries in the svc_cb_list */ bool sv_bc_enabled; /* service uses backchannel */ #endif /* CONFIG_SUNRPC_BACKCHANNEL */ }; /* * We use sv_nrthreads as a reference count. svc_destroy() drops * this refcount, so we need to bump it up around operations that * change the number of threads. Horrible, but there it is. * Should be called with the "service mutex" held. */ static inline void svc_get(struct svc_serv *serv) { serv->sv_nrthreads++; } /* * Maximum payload size supported by a kernel RPC server. * This is use to determine the max number of pages nfsd is * willing to return in a single READ operation. * * These happen to all be powers of 2, which is not strictly * necessary but helps enforce the real limitation, which is * that they should be multiples of PAGE_SIZE. * * For UDP transports, a block plus NFS,RPC, and UDP headers * has to fit into the IP datagram limit of 64K. The largest * feasible number for all known page sizes is probably 48K, * but we choose 32K here. This is the same as the historical * Linux limit; someone who cares more about NFS/UDP performance * can test a larger number. * * For TCP transports we have more freedom. A size of 1MB is * chosen to match the client limit. Other OSes are known to * have larger limits, but those numbers are probably beyond * the point of diminishing returns. */ #define RPCSVC_MAXPAYLOAD (1*1024*1024u) #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) extern u32 svc_max_payload(const struct svc_rqst *rqstp); /* * RPC Requsts and replies are stored in one or more pages. * We maintain an array of pages for each server thread. * Requests are copied into these pages as they arrive. Remaining * pages are available to write the reply into. * * Pages are sent using ->sendpage so each server thread needs to * allocate more to replace those used in sending. To help keep track * of these pages we have a receive list where all pages initialy live, * and a send list where pages are moved to when there are to be part * of a reply. * * We use xdr_buf for holding responses as it fits well with NFS * read responses (that have a header, and some data pages, and possibly * a tail) and means we can share some client side routines. * * The xdr_buf.head kvec always points to the first page in the rq_*pages * list. The xdr_buf.pages pointer points to the second page on that * list. xdr_buf.tail points to the end of the first page. * This assumes that the non-page part of an rpc reply will fit * in a page - NFSd ensures this. lockd also has no trouble. * * Each request/reply pair can have at most one "payload", plus two pages, * one for the request, and one for the reply. * We using ->sendfile to return read data, we might need one extra page * if the request is not page-aligned. So add another '1'. */ #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ + 2 + 1) static inline u32 svc_getnl(struct kvec *iov) { __be32 val, *vp; vp = iov->iov_base; val = *vp++; iov->iov_base = (void*)vp; iov->iov_len -= sizeof(__be32); return ntohl(val); } static inline void svc_putnl(struct kvec *iov, u32 val) { __be32 *vp = iov->iov_base + iov->iov_len; *vp = htonl(val); iov->iov_len += sizeof(__be32); } static inline __be32 svc_getu32(struct kvec *iov) { __be32 val, *vp; vp = iov->iov_base; val = *vp++; iov->iov_base = (void*)vp; iov->iov_len -= sizeof(__be32); return val; } static inline void svc_ungetu32(struct kvec *iov) { __be32 *vp = (__be32 *)iov->iov_base; iov->iov_base = (void *)(vp - 1); iov->iov_len += sizeof(*vp); } static inline void svc_putu32(struct kvec *iov, __be32 val) { __be32 *vp = iov->iov_base + iov->iov_len; *vp = val; iov->iov_len += sizeof(__be32); } /* * The context of a single thread, including the request currently being * processed. */ struct svc_rqst { struct list_head rq_all; /* all threads list */ struct rcu_head rq_rcu_head; /* for RCU deferred kfree */ struct svc_xprt * rq_xprt; /* transport ptr */ struct sockaddr_storage rq_addr; /* peer address */ size_t rq_addrlen; struct sockaddr_storage rq_daddr; /* dest addr of request * - reply from here */ size_t rq_daddrlen; struct svc_serv * rq_server; /* RPC service definition */ struct svc_pool * rq_pool; /* thread pool */ const struct svc_procedure *rq_procinfo;/* procedure info */ struct auth_ops * rq_authop; /* authentication flavour */ struct svc_cred rq_cred; /* auth info */ void * rq_xprt_ctxt; /* transport specific context ptr */ struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ size_t rq_xprt_hlen; /* xprt header len */ struct xdr_buf rq_arg; struct xdr_buf rq_res; struct page *rq_pages[RPCSVC_MAXPAGES + 1]; struct page * *rq_respages; /* points into rq_pages */ struct page * *rq_next_page; /* next reply page to use */ struct page * *rq_page_end; /* one past the last page */ struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ __be32 rq_xid; /* transmission id */ u32 rq_prog; /* program number */ u32 rq_vers; /* program version */ u32 rq_proc; /* procedure number */ u32 rq_prot; /* IP protocol */ int rq_cachetype; /* catering to nfsd */ #define RQ_SECURE (0) /* secure port */ #define RQ_LOCAL (1) /* local request */ #define RQ_USEDEFERRAL (2) /* use deferral */ #define RQ_DROPME (3) /* drop current reply */ #define RQ_SPLICE_OK (4) /* turned off in gss privacy * to prevent encrypting page * cache pages */ #define RQ_VICTIM (5) /* about to be shut down */ #define RQ_BUSY (6) /* request is busy */ #define RQ_DATA (7) /* request has data */ #define RQ_AUTHERR (8) /* Request status is auth error */ unsigned long rq_flags; /* flags field */ ktime_t rq_qtime; /* enqueue time */ void * rq_argp; /* decoded arguments */ void * rq_resp; /* xdr'd results */ void * rq_auth_data; /* flavor-specific data */ int rq_auth_slack; /* extra space xdr code * should leave in head * for krb5i, krb5p. */ int rq_reserved; /* space on socket outq * reserved for this request */ ktime_t rq_stime; /* start time */ struct cache_req rq_chandle; /* handle passed to caches for * request delaying */ /* Catering to nfsd */ struct auth_domain * rq_client; /* RPC peer info */ struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ struct svc_cacherep * rq_cacherep; /* cache info */ struct task_struct *rq_task; /* service thread */ spinlock_t rq_lock; /* per-request lock */ struct net *rq_bc_net; /* pointer to backchannel's * net namespace */ }; #define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net) /* * Rigorous type checking on sockaddr type conversions */ static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst) { return (struct sockaddr_in *) &rqst->rq_addr; } static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst) { return (struct sockaddr_in6 *) &rqst->rq_addr; } static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst) { return (struct sockaddr *) &rqst->rq_addr; } static inline struct sockaddr_in *svc_daddr_in(const struct svc_rqst *rqst) { return (struct sockaddr_in *) &rqst->rq_daddr; } static inline struct sockaddr_in6 *svc_daddr_in6(const struct svc_rqst *rqst) { return (struct sockaddr_in6 *) &rqst->rq_daddr; } static inline struct sockaddr *svc_daddr(const struct svc_rqst *rqst) { return (struct sockaddr *) &rqst->rq_daddr; } /* * Check buffer bounds after decoding arguments */ static inline int xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p) { char *cp = (char *)p; struct kvec *vec = &rqstp->rq_arg.head[0]; return cp >= (char*)vec->iov_base && cp <= (char*)vec->iov_base + vec->iov_len; } static inline int xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p) { struct kvec *vec = &rqstp->rq_res.head[0]; char *cp = (char*)p; vec->iov_len = cp - (char*)vec->iov_base; return vec->iov_len <= PAGE_SIZE; } static inline void svc_free_res_pages(struct svc_rqst *rqstp) { while (rqstp->rq_next_page != rqstp->rq_respages) { struct page **pp = --rqstp->rq_next_page; if (*pp) { put_page(*pp); *pp = NULL; } } } struct svc_deferred_req { u32 prot; /* protocol (UDP or TCP) */ struct svc_xprt *xprt; struct sockaddr_storage addr; /* where reply must go */ size_t addrlen; struct sockaddr_storage daddr; /* where reply must come from */ size_t daddrlen; struct cache_deferred_req handle; size_t xprt_hlen; int argslen; __be32 args[0]; }; struct svc_process_info { union { int (*dispatch)(struct svc_rqst *, __be32 *); struct { unsigned int lovers; unsigned int hivers; } mismatch; }; }; /* * List of RPC programs on the same transport endpoint */ struct svc_program { struct svc_program * pg_next; /* other programs (same xprt) */ u32 pg_prog; /* program number */ unsigned int pg_lovers; /* lowest version */ unsigned int pg_hivers; /* highest version */ unsigned int pg_nvers; /* number of versions */ const struct svc_version **pg_vers; /* version array */ char * pg_name; /* service name */ char * pg_class; /* class name: services sharing authentication */ struct svc_stat * pg_stats; /* rpc statistics */ int (*pg_authenticate)(struct svc_rqst *); __be32 (*pg_init_request)(struct svc_rqst *, const struct svc_program *, struct svc_process_info *); int (*pg_rpcbind_set)(struct net *net, const struct svc_program *, u32 version, int family, unsigned short proto, unsigned short port); }; /* * RPC program version */ struct svc_version { u32 vs_vers; /* version number */ u32 vs_nproc; /* number of procedures */ const struct svc_procedure *vs_proc; /* per-procedure info */ unsigned int *vs_count; /* call counts */ u32 vs_xdrsize; /* xdrsize needed for this version */ /* Don't register with rpcbind */ bool vs_hidden; /* Don't care if the rpcbind registration fails */ bool vs_rpcb_optnl; /* Need xprt with congestion control */ bool vs_need_cong_ctrl; /* Override dispatch function (e.g. when caching replies). * A return value of 0 means drop the request. * vs_dispatch == NULL means use default dispatcher. */ int (*vs_dispatch)(struct svc_rqst *, __be32 *); }; /* * RPC procedure info */ struct svc_procedure { /* process the request: */ __be32 (*pc_func)(struct svc_rqst *); /* XDR decode args: */ int (*pc_decode)(struct svc_rqst *, __be32 *data); /* XDR encode result: */ int (*pc_encode)(struct svc_rqst *, __be32 *data); /* XDR free result: */ void (*pc_release)(struct svc_rqst *); unsigned int pc_argsize; /* argument struct size */ unsigned int pc_ressize; /* result struct size */ unsigned int pc_cachetype; /* cache info (NFS) */ unsigned int pc_xdrressize; /* maximum size of XDR reply */ }; /* * Mode for mapping cpus to pools. */ enum { SVC_POOL_AUTO = -1, /* choose one of the others */ SVC_POOL_GLOBAL, /* no mapping, just a single global pool * (legacy & UP mode) */ SVC_POOL_PERCPU, /* one pool per cpu */ SVC_POOL_PERNODE /* one pool per numa node */ }; struct svc_pool_map { int count; /* How many svc_servs use us */ int mode; /* Note: int not enum to avoid * warnings about "enumeration value * not handled in switch" */ unsigned int npools; unsigned int *pool_to; /* maps pool id to cpu or node */ unsigned int *to_pool; /* maps cpu or node to pool id */ }; extern struct svc_pool_map svc_pool_map; /* * Function prototypes. */ int svc_rpcb_setup(struct svc_serv *serv, struct net *net); void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net); int svc_bind(struct svc_serv *serv, struct net *net); struct svc_serv *svc_create(struct svc_program *, unsigned int, const struct svc_serv_ops *); struct svc_rqst *svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node); struct svc_rqst *svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node); void svc_rqst_free(struct svc_rqst *); void svc_exit_thread(struct svc_rqst *); unsigned int svc_pool_map_get(void); void svc_pool_map_put(void); struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, const struct svc_serv_ops *); int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); int svc_set_num_threads_sync(struct svc_serv *, struct svc_pool *, int); int svc_pool_stats_open(struct svc_serv *serv, struct file *file); void svc_destroy(struct svc_serv *); void svc_shutdown_net(struct svc_serv *, struct net *); int svc_process(struct svc_rqst *); int bc_svc_process(struct svc_serv *, struct rpc_rqst *, struct svc_rqst *); int svc_register(const struct svc_serv *, struct net *, const int, const unsigned short, const unsigned short); void svc_wake_up(struct svc_serv *); void svc_reserve(struct svc_rqst *rqstp, int space); struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); char * svc_print_addr(struct svc_rqst *, char *, size_t); unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, struct page **pages, struct kvec *first, size_t total); char *svc_fill_symlink_pathname(struct svc_rqst *rqstp, struct kvec *first, void *p, size_t total); __be32 svc_return_autherr(struct svc_rqst *rqstp, __be32 auth_err); __be32 svc_generic_init_request(struct svc_rqst *rqstp, const struct svc_program *progp, struct svc_process_info *procinfo); int svc_generic_rpcbind_set(struct net *net, const struct svc_program *progp, u32 version, int family, unsigned short proto, unsigned short port); int svc_rpcbind_set_version(struct net *net, const struct svc_program *progp, u32 version, int family, unsigned short proto, unsigned short port); #define RPC_MAX_ADDRBUFLEN (63U) /* * When we want to reduce the size of the reserved space in the response * buffer, we need to take into account the size of any checksum data that * may be at the end of the packet. This is difficult to determine exactly * for all cases without actually generating the checksum, so we just use a * static value. */ static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space) { svc_reserve(rqstp, space + rqstp->rq_auth_slack); } #endif /* SUNRPC_SVC_H */