v4.19.13 snapshot.
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
new file mode 100644
index 0000000..73e130a
--- /dev/null
+++ b/include/linux/sunrpc/svc.h
@@ -0,0 +1,519 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * linux/include/linux/sunrpc/svc.h
+ *
+ * RPC server declarations.
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+
+#ifndef SUNRPC_SVC_H
+#define SUNRPC_SVC_H
+
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/sunrpc/types.h>
+#include <linux/sunrpc/xdr.h>
+#include <linux/sunrpc/auth.h>
+#include <linux/sunrpc/svcauth.h>
+#include <linux/wait.h>
+#include <linux/mm.h>
+
+/* 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 */
+ struct svc_xprt *sv_bc_xprt; /* callback on fore channel */
+#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 */
+ 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 */
+};
+
+#define SVC_NET(svc_rqst) (svc_rqst->rq_xprt->xpt_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];
+};
+
+/*
+ * 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 *);
+};
+
+/*
+ * 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);
+
+#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 */