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Diffstat (limited to '')
| -rw-r--r-- | include/linux/sunrpc/xprt.h | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h new file mode 100644 index 000000000..e7b997d6f --- /dev/null +++ b/include/linux/sunrpc/xprt.h @@ -0,0 +1,512 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * 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> + +#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 */ + + union { + struct list_head rq_list; /* Slot allocation list */ + struct rb_node rq_recv; /* Receive queue */ + }; + + struct list_head rq_xmit; /* Send queue */ + struct list_head rq_xmit2; /* Send queue */ + + 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_minortimeo; /* minor 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 */ + atomic_t rq_pin; + + /* + * 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); + void (*prepare_request)(struct rpc_rqst *req); + int (*send_request)(struct rpc_rqst *req); + void (*wait_for_reply_request)(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); + size_t (*bc_maxpayload)(struct rpc_xprt *xprt); + unsigned int (*bc_num_slots)(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 */ + const 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 */ + + 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 */ + reuseport : 1; /* reuse port on reconnect */ + 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 + */ + atomic_long_t queuelen; + spinlock_t transport_lock; /* lock transport info */ + spinlock_t reserve_lock; /* lock slot table */ + spinlock_t queue_lock; /* send/receive queue lock */ + u32 xid; /* Next XID value to use */ + struct rpc_task * snd_task; /* Task blocked in send */ + + struct list_head xmit_queue; /* Send queue */ + + 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 */ + unsigned int bc_alloc_max; + unsigned int bc_alloc_count; /* Total number of preallocs */ + atomic_t bc_slot_count; /* Number of allocated 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 rb_root recv_queue; /* Receive queue */ + + 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]; + const char * netid[]; +}; + +/* + * Generic internal transport functions + */ +struct rpc_xprt *xprt_create_transport(struct xprt_create *args); +void xprt_connect(struct rpc_task *task); +unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt); +void xprt_reconnect_backoff(struct rpc_xprt *xprt, + unsigned long init_to); +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_request_prepare(struct rpc_rqst *req); +bool xprt_prepare_transmit(struct rpc_task *task); +void xprt_request_enqueue_transmit(struct rpc_task *task); +void xprt_request_enqueue_receive(struct rpc_task *task); +void xprt_request_wait_receive(struct rpc_task *task); +void xprt_request_dequeue_xprt(struct rpc_task *task); +bool xprt_request_need_retransmit(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 *); +void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task); +bool xprt_wake_up_backlog(struct rpc_xprt *xprt, struct rpc_rqst *req); + +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_wait_for_reply_request_def(struct rpc_task *task); +void xprt_wait_for_reply_request_rtt(struct rpc_task *task); +void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); +void xprt_wait_for_buffer_space(struct rpc_xprt *xprt); +bool 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_update_rtt(struct rpc_task *task); +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); +bool xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req); +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) +#define XPRT_CWND_WAIT (10) +#define XPRT_WRITE_SPACE (11) +#define XPRT_SND_IS_COOKIE (12) + +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_atomic(); + clear_bit(XPRT_CONNECTING, &xprt->state); + smp_mb__after_atomic(); +} + +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_atomic(); + clear_bit(XPRT_BINDING, &xprt->state); + smp_mb__after_atomic(); +} + +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 /* _LINUX_SUNRPC_XPRT_H */ |