Edit File: xprt.h
/* * linux/include/linux/sunrpc/xprt.h * * Declarations for the RPC transport interface. * * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> */ #ifndef _LINUX_SUNRPC_XPRT_H #define _LINUX_SUNRPC_XPRT_H #include <linux/uio.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/ktime.h> #include <linux/kref.h> #include <linux/sunrpc/sched.h> #include <linux/sunrpc/xdr.h> #include <linux/sunrpc/msg_prot.h> #ifdef __KERNEL__ #define RPC_MIN_SLOT_TABLE (2U) #define RPC_DEF_SLOT_TABLE (16U) #define RPC_MAX_SLOT_TABLE_LIMIT (65536U) #define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT #define RPC_CWNDSHIFT (8U) #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) #define RPC_INITCWND RPC_CWNDSCALE #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) /* * This describes a timeout strategy */ struct rpc_timeout { unsigned long to_initval, /* initial timeout */ to_maxval, /* max timeout */ to_increment; /* if !exponential */ unsigned int to_retries; /* max # of retries */ unsigned char to_exponential; }; enum rpc_display_format_t { RPC_DISPLAY_ADDR = 0, RPC_DISPLAY_PORT, RPC_DISPLAY_PROTO, RPC_DISPLAY_HEX_ADDR, RPC_DISPLAY_HEX_PORT, RPC_DISPLAY_NETID, RPC_DISPLAY_MAX, }; struct rpc_task; struct rpc_xprt; struct seq_file; struct svc_serv; struct net; /* * This describes a complete RPC request */ struct rpc_rqst { /* * This is the user-visible part */ struct rpc_xprt * rq_xprt; /* RPC client */ struct xdr_buf rq_snd_buf; /* send buffer */ struct xdr_buf rq_rcv_buf; /* recv buffer */ /* * This is the private part */ struct rpc_task * rq_task; /* RPC task data */ struct rpc_cred * rq_cred; /* Bound cred */ __be32 rq_xid; /* request XID */ int rq_cong; /* has incremented xprt->cong */ u32 rq_seqno; /* gss seq no. used on req. */ int rq_enc_pages_num; struct page **rq_enc_pages; /* scratch pages for use by gss privacy code */ void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ struct list_head rq_list; void *rq_buffer; /* Call XDR encode buffer */ size_t rq_callsize; void *rq_rbuffer; /* Reply XDR decode buffer */ size_t rq_rcvsize; size_t rq_xmit_bytes_sent; /* total bytes sent */ size_t rq_reply_bytes_recvd; /* total reply bytes */ /* received */ struct xdr_buf rq_private_buf; /* The receive buffer * used in the softirq. */ unsigned long rq_majortimeo; /* major timeout alarm */ unsigned long rq_timeout; /* Current timeout value */ ktime_t rq_rtt; /* round-trip time */ unsigned int rq_retries; /* # of retries */ unsigned int rq_connect_cookie; /* A cookie used to track the state of the transport connection */ /* * Partial send handling */ u32 rq_bytes_sent; /* Bytes we have sent */ ktime_t rq_xtime; /* transmit time stamp */ int rq_ntrans; #if defined(CONFIG_SUNRPC_BACKCHANNEL) struct list_head rq_bc_list; /* Callback service list */ unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ #endif /* CONFIG_SUNRPC_BACKCHANEL */ }; #define rq_svec rq_snd_buf.head #define rq_slen rq_snd_buf.len struct rpc_xprt_ops { void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); void (*free_slot)(struct rpc_xprt *xprt, struct rpc_rqst *req); void (*rpcbind)(struct rpc_task *task); void (*set_port)(struct rpc_xprt *xprt, unsigned short port); void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); int (*buf_alloc)(struct rpc_task *task); void (*buf_free)(struct rpc_task *task); int (*send_request)(struct rpc_task *task); void (*set_retrans_timeout)(struct rpc_task *task); void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); void (*release_request)(struct rpc_task *task); void (*close)(struct rpc_xprt *xprt); void (*destroy)(struct rpc_xprt *xprt); void (*set_connect_timeout)(struct rpc_xprt *xprt, unsigned long connect_timeout, unsigned long reconnect_timeout); void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); int (*enable_swap)(struct rpc_xprt *xprt); void (*disable_swap)(struct rpc_xprt *xprt); void (*inject_disconnect)(struct rpc_xprt *xprt); int (*bc_setup)(struct rpc_xprt *xprt, unsigned int min_reqs); int (*bc_up)(struct svc_serv *serv, struct net *net); size_t (*bc_maxpayload)(struct rpc_xprt *xprt); void (*bc_free_rqst)(struct rpc_rqst *rqst); void (*bc_destroy)(struct rpc_xprt *xprt, unsigned int max_reqs); }; /* * RPC transport identifiers * * To preserve compatibility with the historical use of raw IP protocol * id's for transport selection, UDP and TCP identifiers are specified * with the previous values. No such restriction exists for new transports, * except that they may not collide with these values (17 and 6, * respectively). */ #define XPRT_TRANSPORT_BC (1 << 31) enum xprt_transports { XPRT_TRANSPORT_UDP = IPPROTO_UDP, XPRT_TRANSPORT_TCP = IPPROTO_TCP, XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, XPRT_TRANSPORT_RDMA = 256, XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, XPRT_TRANSPORT_LOCAL = 257, }; struct rpc_xprt { struct kref kref; /* Reference count */ struct rpc_xprt_ops * ops; /* transport methods */ const struct rpc_timeout *timeout; /* timeout parms */ struct sockaddr_storage addr; /* server address */ size_t addrlen; /* size of server address */ int prot; /* IP protocol */ unsigned long cong; /* current congestion */ unsigned long cwnd; /* congestion window */ size_t max_payload; /* largest RPC payload size, in bytes */ unsigned int tsh_size; /* size of transport specific header */ struct rpc_wait_queue binding; /* requests waiting on rpcbind */ struct rpc_wait_queue sending; /* requests waiting to send */ struct rpc_wait_queue pending; /* requests in flight */ struct rpc_wait_queue backlog; /* waiting for slot */ struct list_head free; /* free slots */ unsigned int max_reqs; /* max number of slots */ unsigned int min_reqs; /* min number of slots */ unsigned int num_reqs; /* total slots */ unsigned long state; /* transport state */ unsigned char resvport : 1; /* use a reserved port */ atomic_t swapper; /* we're swapping over this transport */ unsigned int bind_index; /* bind function index */ /* * Multipath */ struct list_head xprt_switch; /* * Connection of transports */ unsigned long bind_timeout, reestablish_timeout; unsigned int connect_cookie; /* A cookie that gets bumped every time the transport is reconnected */ /* * Disconnection of idle transports */ struct work_struct task_cleanup; struct timer_list timer; unsigned long last_used, idle_timeout, connect_timeout, max_reconnect_timeout; /* * Send stuff */ spinlock_t transport_lock; /* lock transport info */ spinlock_t reserve_lock; /* lock slot table */ spinlock_t recv_lock; /* lock receive list */ u32 xid; /* Next XID value to use */ struct rpc_task * snd_task; /* Task blocked in send */ struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ #if defined(CONFIG_SUNRPC_BACKCHANNEL) struct svc_serv *bc_serv; /* The RPC service which will */ /* process the callback */ int bc_alloc_count; /* Total number of preallocs */ atomic_t bc_free_slots; spinlock_t bc_pa_lock; /* Protects the preallocated * items */ struct list_head bc_pa_list; /* List of preallocated * backchannel rpc_rqst's */ #endif /* CONFIG_SUNRPC_BACKCHANNEL */ struct list_head recv; struct { unsigned long bind_count, /* total number of binds */ connect_count, /* total number of connects */ connect_start, /* connect start timestamp */ connect_time, /* jiffies waiting for connect */ sends, /* how many complete requests */ recvs, /* how many complete requests */ bad_xids, /* lookup_rqst didn't find XID */ max_slots; /* max rpc_slots used */ unsigned long long req_u, /* average requests on the wire */ bklog_u, /* backlog queue utilization */ sending_u, /* send q utilization */ pending_u; /* pend q utilization */ } stat; struct net *xprt_net; const char *servername; const char *address_strings[RPC_DISPLAY_MAX]; #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) struct dentry *debugfs; /* debugfs directory */ atomic_t inject_disconnect; #endif struct rcu_head rcu; }; #if defined(CONFIG_SUNRPC_BACKCHANNEL) /* * Backchannel flags */ #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ /* buffer in use */ #endif /* CONFIG_SUNRPC_BACKCHANNEL */ #if defined(CONFIG_SUNRPC_BACKCHANNEL) static inline int bc_prealloc(struct rpc_rqst *req) { return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); } #else static inline int bc_prealloc(struct rpc_rqst *req) { return 0; } #endif /* CONFIG_SUNRPC_BACKCHANNEL */ #define XPRT_CREATE_INFINITE_SLOTS (1U) #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) struct xprt_create { int ident; /* XPRT_TRANSPORT identifier */ struct net * net; struct sockaddr * srcaddr; /* optional local address */ struct sockaddr * dstaddr; /* remote peer address */ size_t addrlen; const char *servername; struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ struct rpc_xprt_switch *bc_xps; unsigned int flags; }; struct xprt_class { struct list_head list; int ident; /* XPRT_TRANSPORT identifier */ struct rpc_xprt * (*setup)(struct xprt_create *); struct module *owner; char name[32]; }; /* * Generic internal transport functions */ struct rpc_xprt *xprt_create_transport(struct xprt_create *args); void xprt_connect(struct rpc_task *task); void xprt_reserve(struct rpc_task *task); void xprt_retry_reserve(struct rpc_task *task); int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req); void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); bool xprt_prepare_transmit(struct rpc_task *task); void xprt_transmit(struct rpc_task *task); void xprt_end_transmit(struct rpc_task *task); int xprt_adjust_timeout(struct rpc_rqst *req); void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_release(struct rpc_task *task); struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); void xprt_put(struct rpc_xprt *xprt); struct rpc_xprt * xprt_alloc(struct net *net, size_t size, unsigned int num_prealloc, unsigned int max_req); void xprt_free(struct rpc_xprt *); static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p) { return p + xprt->tsh_size; } static inline int xprt_enable_swap(struct rpc_xprt *xprt) { return xprt->ops->enable_swap(xprt); } static inline void xprt_disable_swap(struct rpc_xprt *xprt) { xprt->ops->disable_swap(xprt); } /* * Transport switch helper functions */ int xprt_register_transport(struct xprt_class *type); int xprt_unregister_transport(struct xprt_class *type); int xprt_load_transport(const char *); void xprt_set_retrans_timeout_def(struct rpc_task *task); void xprt_set_retrans_timeout_rtt(struct rpc_task *task); void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action); void xprt_write_space(struct rpc_xprt *xprt); void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); void xprt_complete_rqst(struct rpc_task *task, int copied); void xprt_pin_rqst(struct rpc_rqst *req); void xprt_unpin_rqst(struct rpc_rqst *req); void xprt_release_rqst_cong(struct rpc_task *task); void xprt_disconnect_done(struct rpc_xprt *xprt); void xprt_force_disconnect(struct rpc_xprt *xprt); void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); void xprt_unlock_connect(struct rpc_xprt *, void *); /* * Reserved bit positions in xprt->state */ #define XPRT_LOCKED (0) #define XPRT_CONNECTED (1) #define XPRT_CONNECTING (2) #define XPRT_CLOSE_WAIT (3) #define XPRT_BOUND (4) #define XPRT_BINDING (5) #define XPRT_CLOSING (6) #define XPRT_CONGESTED (9) static inline void xprt_set_connected(struct rpc_xprt *xprt) { set_bit(XPRT_CONNECTED, &xprt->state); } static inline void xprt_clear_connected(struct rpc_xprt *xprt) { clear_bit(XPRT_CONNECTED, &xprt->state); } static inline int xprt_connected(struct rpc_xprt *xprt) { return test_bit(XPRT_CONNECTED, &xprt->state); } static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) { return test_and_set_bit(XPRT_CONNECTED, &xprt->state); } static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) { return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); } static inline void xprt_clear_connecting(struct rpc_xprt *xprt) { smp_mb__before_clear_bit(); clear_bit(XPRT_CONNECTING, &xprt->state); smp_mb__after_clear_bit(); } static inline int xprt_connecting(struct rpc_xprt *xprt) { return test_bit(XPRT_CONNECTING, &xprt->state); } static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) { return test_and_set_bit(XPRT_CONNECTING, &xprt->state); } static inline void xprt_set_bound(struct rpc_xprt *xprt) { test_and_set_bit(XPRT_BOUND, &xprt->state); } static inline int xprt_bound(struct rpc_xprt *xprt) { return test_bit(XPRT_BOUND, &xprt->state); } static inline void xprt_clear_bound(struct rpc_xprt *xprt) { clear_bit(XPRT_BOUND, &xprt->state); } static inline void xprt_clear_binding(struct rpc_xprt *xprt) { smp_mb__before_clear_bit(); clear_bit(XPRT_BINDING, &xprt->state); smp_mb__after_clear_bit(); } static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) { return test_and_set_bit(XPRT_BINDING, &xprt->state); } #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) extern unsigned int rpc_inject_disconnect; static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) { if (!rpc_inject_disconnect) return; if (atomic_dec_return(&xprt->inject_disconnect)) return; atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect); xprt->ops->inject_disconnect(xprt); } #else static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) { } #endif #endif /* __KERNEL__*/ #endif /* _LINUX_SUNRPC_XPRT_H */