[mirror_ubuntu-zesty-kernel.git] / include / linux / sunrpc / 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_xprtdata;	/* Per-xprt private data */
	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		(*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		(*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 */
	atomic_t		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,
				max_reconnect_timeout;

	/*
	 * Send stuff
	 */
	spinlock_t		transport_lock;	/* lock transport info */
	spinlock_t		reserve_lock;	/* lock slot table */
	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_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_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_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 /* __KERNEL__*/

#endif /* _LINUX_SUNRPC_XPRT_H */
Commit	Line	Data
1da177e4	1	/*
55aa4f58	2	* linux/include/linux/sunrpc/xprt.h
1da177e4 LT	3	*
	4	* Declarations for the RPC transport interface.
	5	*
	6	* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
	7	*/
	8
	9	#ifndef _LINUX_SUNRPC_XPRT_H
	10	#define _LINUX_SUNRPC_XPRT_H
	11
	12	#include <linux/uio.h>
	13	#include <linux/socket.h>
	14	#include <linux/in.h>
ff839970	15	#include <linux/ktime.h>
30c5116b	16	#include <linux/kref.h>
1da177e4 LT	17	#include <linux/sunrpc/sched.h>
1da177e4 LT	18	#include <linux/sunrpc/xdr.h>
7adae489	19	#include <linux/sunrpc/msg_prot.h>
1da177e4	20
96802a09 FM	21	#ifdef __KERNEL__
96802a09 FM	22
1da177e4 LT	23	#define RPC_MIN_SLOT_TABLE (2U)
1da177e4 LT	24	#define RPC_DEF_SLOT_TABLE (16U)
d9ba131d	25	#define RPC_MAX_SLOT_TABLE_LIMIT (65536U)
88338124	26	#define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT
1da177e4	27
4f4cf5ad CL	28	#define RPC_CWNDSHIFT (8U)
	29	#define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT)
	30	#define RPC_INITCWND RPC_CWNDSCALE
	31	#define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT)
	32	#define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
	33
1da177e4 LT	34	/*
	35	* This describes a timeout strategy
	36	*/
	37	struct rpc_timeout {
	38	unsigned long to_initval, /* initial timeout */
	39	to_maxval, /* max timeout */
	40	to_increment; /* if !exponential */
	41	unsigned int to_retries; /* max # of retries */
	42	unsigned char to_exponential;
	43	};
	44
edb267a6 CL	45	enum rpc_display_format_t {
	46	RPC_DISPLAY_ADDR = 0,
	47	RPC_DISPLAY_PORT,
	48	RPC_DISPLAY_PROTO,
fbfe3cc6 CL	49	RPC_DISPLAY_HEX_ADDR,
fbfe3cc6 CL	50	RPC_DISPLAY_HEX_PORT,
4417c8c4	51	RPC_DISPLAY_NETID,
edb267a6 CL	52	RPC_DISPLAY_MAX,
	53	};
	54
529b33c6 CL	55	struct rpc_task;
529b33c6 CL	56	struct rpc_xprt;
e99170ff	57	struct seq_file;
76566773 CL	58	struct svc_serv;
76566773 CL	59	struct net;
529b33c6	60
1da177e4 LT	61	/*
	62	* This describes a complete RPC request
	63	*/
	64	struct rpc_rqst {
	65	/*
	66	* This is the user-visible part
	67	*/
	68	struct rpc_xprt * rq_xprt; /* RPC client */
	69	struct xdr_buf rq_snd_buf; /* send buffer */
	70	struct xdr_buf rq_rcv_buf; /* recv buffer */
	71
	72	/*
	73	* This is the private part
	74	*/
	75	struct rpc_task * rq_task; /* RPC task data */
a17c2153	76	struct rpc_cred * rq_cred; /* Bound cred */
d8ed029d	77	__be32 rq_xid; /* request XID */
1da177e4	78	int rq_cong; /* has incremented xprt->cong */
1da177e4	79	u32 rq_seqno; /* gss seq no. used on req. */
ead5e1c2 BF	80	int rq_enc_pages_num;
	81	struct page *rq_enc_pages; / scratch pages for use by
	82	gss privacy code */
	83	void (rq_release_snd_buf)(struct rpc_rqst ); /* release rq_enc_pages */
1da177e4 LT	84	struct list_head rq_list;
1da177e4 LT	85
5a6d1db4	86	void rq_xprtdata; / Per-xprt private data */
b9c5bc03	87	void rq_buffer; / Call XDR encode buffer */
68778945 CL	88	size_t rq_callsize;
	89	void rq_rbuffer; / Reply XDR decode buffer */
	90	size_t rq_rcvsize;
d60dbb20 TM	91	size_t rq_xmit_bytes_sent; /* total bytes sent */
	92	size_t rq_reply_bytes_recvd; /* total reply bytes */
	93	/* received */
02107148	94
1da177e4 LT	95	struct xdr_buf rq_private_buf; /* The receive buffer
	96	* used in the softirq.
	97	*/
	98	unsigned long rq_majortimeo; /* major timeout alarm */
	99	unsigned long rq_timeout; /* Current timeout value */
d60dbb20	100	ktime_t rq_rtt; /* round-trip time */
1da177e4	101	unsigned int rq_retries; /* # of retries */
7c1d71cf TM	102	unsigned int rq_connect_cookie;
	103	/* A cookie used to track the
	104	state of the transport
	105	connection */
1da177e4 LT	106
	107	/*
	108	* Partial send handling
	109	*/
1da177e4 LT	110	u32 rq_bytes_sent; /* Bytes we have sent */
1da177e4 LT	111
ff839970	112	ktime_t rq_xtime; /* transmit time stamp */
1da177e4	113	int rq_ntrans;
56632b5b	114
9e00abc3	115	#if defined(CONFIG_SUNRPC_BACKCHANNEL)
56632b5b RL	116	struct list_head rq_bc_list; /* Callback service list */
	117	unsigned long rq_bc_pa_state; /* Backchannel prealloc state */
	118	struct list_head rq_bc_pa_list; /* Backchannel prealloc list */
9e00abc3	119	#endif /* CONFIG_SUNRPC_BACKCHANEL */
1da177e4 LT	120	};
	121	#define rq_svec rq_snd_buf.head
	122	#define rq_slen rq_snd_buf.len
	123
a246b010	124	struct rpc_xprt_ops {
470056c2	125	void (set_buffer_size)(struct rpc_xprt xprt, size_t sndsize, size_t rcvsize);
43cedbf0	126	int (reserve_xprt)(struct rpc_xprt xprt, struct rpc_task *task);
49e9a890	127	void (release_xprt)(struct rpc_xprt xprt, struct rpc_task *task);
f39c1bfb	128	void (alloc_slot)(struct rpc_xprt xprt, struct rpc_task *task);
bbf7c1dd	129	void (rpcbind)(struct rpc_task task);
92200412	130	void (set_port)(struct rpc_xprt xprt, unsigned short port);
1b092092	131	void (connect)(struct rpc_xprt xprt, struct rpc_task *task);
5fe6eaa1	132	int (buf_alloc)(struct rpc_task task);
3435c74a	133	void (buf_free)(struct rpc_task task);
a246b010	134	int (send_request)(struct rpc_task task);
fe3aca29	135	void (set_retrans_timeout)(struct rpc_task task);
6a24dfb6	136	void (timer)(struct rpc_xprt xprt, struct rpc_task *task);
a58dd398	137	void (release_request)(struct rpc_task task);
a246b010 CL	138	void (close)(struct rpc_xprt xprt);
a246b010 CL	139	void (destroy)(struct rpc_xprt xprt);
262ca07d	140	void (print_stats)(struct rpc_xprt xprt, struct seq_file *seq);
d67fa4d8 JL	141	int (enable_swap)(struct rpc_xprt xprt);
d67fa4d8 JL	142	void (disable_swap)(struct rpc_xprt xprt);
4a068258	143	void (inject_disconnect)(struct rpc_xprt xprt);
42e5c3e2 CL	144	int (bc_setup)(struct rpc_xprt xprt,
42e5c3e2 CL	145	unsigned int min_reqs);
76566773	146	int (bc_up)(struct svc_serv serv, struct net *net);
6b26cc8c	147	size_t (bc_maxpayload)(struct rpc_xprt xprt);
42e5c3e2 CL	148	void (bc_free_rqst)(struct rpc_rqst rqst);
	149	void (bc_destroy)(struct rpc_xprt xprt,
	150	unsigned int max_reqs);
a246b010	151	};
1da177e4	152
f300baba AB	153	/*
	154	* RPC transport identifiers
	155	*
	156	* To preserve compatibility with the historical use of raw IP protocol
	157	* id's for transport selection, UDP and TCP identifiers are specified
	158	* with the previous values. No such restriction exists for new transports,
	159	* except that they may not collide with these values (17 and 6,
	160	* respectively).
	161	*/
	162	#define XPRT_TRANSPORT_BC (1 << 31)
	163	enum xprt_transports {
	164	XPRT_TRANSPORT_UDP = IPPROTO_UDP,
	165	XPRT_TRANSPORT_TCP = IPPROTO_TCP,
	166	XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP \| XPRT_TRANSPORT_BC,
176e21ee	167	XPRT_TRANSPORT_RDMA = 256,
94684319	168	XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA \| XPRT_TRANSPORT_BC,
176e21ee	169	XPRT_TRANSPORT_LOCAL = 257,
f300baba AB	170	};
f300baba AB	171
1da177e4	172	struct rpc_xprt {
30c5116b	173	struct kref kref; /* Reference count */
a246b010	174	struct rpc_xprt_ops * ops; /* transport methods */
1da177e4	175
ba7392bb	176	const struct rpc_timeout timeout; / timeout parms */
c4efcb1d CL	177	struct sockaddr_storage addr; /* server address */
c4efcb1d CL	178	size_t addrlen; /* size of server address */
1da177e4 LT	179	int prot; /* IP protocol */
	180
	181	unsigned long cong; /* current congestion */
	182	unsigned long cwnd; /* congestion window */
	183
1da177e4 LT	184	size_t max_payload; /* largest RPC payload size,
1da177e4 LT	185	in bytes */
808012fb CL	186	unsigned int tsh_size; /* size of transport specific
808012fb CL	187	header */
1da177e4	188
4a68179d	189	struct rpc_wait_queue binding; /* requests waiting on rpcbind */
1da177e4	190	struct rpc_wait_queue sending; /* requests waiting to send */
1da177e4 LT	191	struct rpc_wait_queue pending; /* requests in flight */
	192	struct rpc_wait_queue backlog; /* waiting for slot */
	193	struct list_head free; /* free slots */
d9ba131d TM	194	unsigned int max_reqs; /* max number of slots */
	195	unsigned int min_reqs; /* min number of slots */
	196	atomic_t num_reqs; /* total slots */
2226feb6	197	unsigned long state; /* transport state */
d19751e7	198	unsigned char resvport : 1; /* use a reserved port */
8e228133	199	atomic_t swapper; /* we're swapping over this
a564b8f0	200	transport */
a509050b	201	unsigned int bind_index; /* bind function index */
1da177e4	202
80b14d5e TM	203	/*
	204	* Multipath
	205	*/
	206	struct list_head xprt_switch;
	207
1da177e4	208	/*
55aa4f58	209	* Connection of transports
1da177e4	210	*/
a8ce4a8f	211	unsigned long bind_timeout,
03bf4b70	212	reestablish_timeout;
7c1d71cf TM	213	unsigned int connect_cookie; /* A cookie that gets bumped
	214	every time the transport
	215	is reconnected */
03bf4b70	216
1da177e4	217	/*
55aa4f58	218	* Disconnection of idle transports
1da177e4 LT	219	*/
	220	struct work_struct task_cleanup;
	221	struct timer_list timer;
03bf4b70	222	unsigned long last_used,
3851f1cd TM	223	idle_timeout,
3851f1cd TM	224	max_reconnect_timeout;
1da177e4 LT	225
	226	/*
	227	* Send stuff
	228	*/
4a0f8c04	229	spinlock_t transport_lock; /* lock transport info */
5dc07727	230	spinlock_t reserve_lock; /* lock slot table */
e744cf2e	231	u32 xid; /* Next XID value to use */
1da177e4	232	struct rpc_task * snd_task; /* Task blocked in send */
4cfc7e60	233	struct svc_xprt bc_xprt; / NFSv4.1 backchannel */
9e00abc3	234	#if defined(CONFIG_SUNRPC_BACKCHANNEL)
56632b5b RL	235	struct svc_serv bc_serv; / The RPC service which will */
56632b5b RL	236	/* process the callback */
0d2a970d TM	237	int bc_alloc_count; /* Total number of preallocs */
0d2a970d TM	238	atomic_t bc_free_slots;
56632b5b RL	239	spinlock_t bc_pa_lock; /* Protects the preallocated
	240	* items */
	241	struct list_head bc_pa_list; /* List of preallocated
	242	* backchannel rpc_rqst's */
9e00abc3	243	#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1da177e4 LT	244	struct list_head recv;
1da177e4 LT	245
262ca07d CL	246	struct {
	247	unsigned long bind_count, /* total number of binds */
	248	connect_count, /* total number of connects */
	249	connect_start, /* connect start timestamp */
	250	connect_time, /* jiffies waiting for connect */
	251	sends, /* how many complete requests */
	252	recvs, /* how many complete requests */
15a45206 AA	253	bad_xids, /* lookup_rqst didn't find XID */
15a45206 AA	254	max_slots; /* max rpc_slots used */
262ca07d CL	255
262ca07d CL	256	unsigned long long req_u, /* average requests on the wire */
15a45206 AA	257	bklog_u, /* backlog queue utilization */
	258	sending_u, /* send q utilization */
	259	pending_u; /* pend q utilization */
262ca07d	260	} stat;
1da177e4	261
37aa2133	262	struct net *xprt_net;
4e0038b6	263	const char *servername;
b454ae90	264	const char *address_strings[RPC_DISPLAY_MAX];
388f0c77 JL	265	#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
388f0c77 JL	266	struct dentry debugfs; / debugfs directory */
4a068258	267	atomic_t inject_disconnect;
388f0c77	268	#endif
fda1bfef	269	struct rcu_head rcu;
1da177e4 LT	270	};
1da177e4 LT	271
9e00abc3	272	#if defined(CONFIG_SUNRPC_BACKCHANNEL)
56632b5b RL	273	/*
	274	* Backchannel flags
	275	*/
	276	#define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */
	277	/* buffer in use */
9e00abc3	278	#endif /* CONFIG_SUNRPC_BACKCHANNEL */
56632b5b	279
9e00abc3	280	#if defined(CONFIG_SUNRPC_BACKCHANNEL)
55ae1aab RL	281	static inline int bc_prealloc(struct rpc_rqst *req)
	282	{
	283	return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state);
	284	}
	285	#else
	286	static inline int bc_prealloc(struct rpc_rqst *req)
	287	{
	288	return 0;
	289	}
9e00abc3	290	#endif /* CONFIG_SUNRPC_BACKCHANNEL */
55ae1aab	291
b7993ceb	292	#define XPRT_CREATE_INFINITE_SLOTS (1U)
33d90ac0	293	#define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1)
b7993ceb	294
3c341b0b	295	struct xprt_create {
4fa016eb	296	int ident; /* XPRT_TRANSPORT identifier */
9a23e332	297	struct net * net;
d3bc9a1d	298	struct sockaddr * srcaddr; /* optional local address */
96802a09 FM	299	struct sockaddr * dstaddr; /* remote peer address */
96802a09 FM	300	size_t addrlen;
4e0038b6	301	const char *servername;
f300baba	302	struct svc_xprt bc_xprt; / NFSv4.1 backchannel */
39a9beab	303	struct rpc_xprt_switch *bc_xps;
b7993ceb	304	unsigned int flags;
96802a09	305	};
1da177e4	306
81c098af TT	307	struct xprt_class {
81c098af TT	308	struct list_head list;
4fa016eb	309	int ident; /* XPRT_TRANSPORT identifier */
3c341b0b	310	struct rpc_xprt * (setup)(struct xprt_create );
81c098af TT	311	struct module *owner;
	312	char name[32];
	313	};
	314
55aa4f58 CL	315	/*
	316	* Generic internal transport functions
	317	*/
3c341b0b	318	struct rpc_xprt xprt_create_transport(struct xprt_create args);
55aa4f58 CL	319	void xprt_connect(struct rpc_task *task);
55aa4f58 CL	320	void xprt_reserve(struct rpc_task *task);
ba60eb25	321	void xprt_retry_reserve(struct rpc_task *task);
43cedbf0 TM	322	int xprt_reserve_xprt(struct rpc_xprt xprt, struct rpc_task task);
43cedbf0 TM	323	int xprt_reserve_xprt_cong(struct rpc_xprt xprt, struct rpc_task task);
f39c1bfb TM	324	void xprt_alloc_slot(struct rpc_xprt xprt, struct rpc_task task);
f39c1bfb TM	325	void xprt_lock_and_alloc_slot(struct rpc_xprt xprt, struct rpc_task task);
90051ea7	326	bool xprt_prepare_transmit(struct rpc_task *task);
55aa4f58	327	void xprt_transmit(struct rpc_task *task);
e0ab53de	328	void xprt_end_transmit(struct rpc_task *task);
1da177e4	329	int xprt_adjust_timeout(struct rpc_rqst *req);
49e9a890 CL	330	void xprt_release_xprt(struct rpc_xprt xprt, struct rpc_task task);
49e9a890 CL	331	void xprt_release_xprt_cong(struct rpc_xprt xprt, struct rpc_task task);
55aa4f58	332	void xprt_release(struct rpc_task *task);
30c5116b	333	struct rpc_xprt * xprt_get(struct rpc_xprt *xprt);
6b6ca86b	334	void xprt_put(struct rpc_xprt *xprt);
d9ba131d TM	335	struct rpc_xprt * xprt_alloc(struct net *net, size_t size,
	336	unsigned int num_prealloc,
	337	unsigned int max_req);
e204e621	338	void xprt_free(struct rpc_xprt *);
55aa4f58	339
d8ed029d	340	static inline __be32 xprt_skip_transport_header(struct rpc_xprt xprt, __be32 *p)
808012fb CL	341	{
	342	return p + xprt->tsh_size;
	343	}
	344
d67fa4d8 JL	345	static inline int
	346	xprt_enable_swap(struct rpc_xprt *xprt)
	347	{
	348	return xprt->ops->enable_swap(xprt);
	349	}
	350
	351	static inline void
	352	xprt_disable_swap(struct rpc_xprt *xprt)
	353	{
	354	xprt->ops->disable_swap(xprt);
	355	}
	356
55aa4f58 CL	357	/*
	358	* Transport switch helper functions
	359	*/
81c098af TT	360	int xprt_register_transport(struct xprt_class *type);
81c098af TT	361	int xprt_unregister_transport(struct xprt_class *type);
441e3e24	362	int xprt_load_transport(const char *);
fe3aca29 CL	363	void xprt_set_retrans_timeout_def(struct rpc_task *task);
fe3aca29 CL	364	void xprt_set_retrans_timeout_rtt(struct rpc_task *task);
55aa4f58	365	void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
b6ddf64f	366	void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
c7b2cae8	367	void xprt_write_space(struct rpc_xprt *xprt);
6a24dfb6	368	void xprt_adjust_cwnd(struct rpc_xprt xprt, struct rpc_task task, int result);
d8ed029d	369	struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
1570c1e4	370	void xprt_complete_rqst(struct rpc_task *task, int copied);
a58dd398	371	void xprt_release_rqst_cong(struct rpc_task *task);
62da3b24	372	void xprt_disconnect_done(struct rpc_xprt *xprt);
66af1e55	373	void xprt_force_disconnect(struct rpc_xprt *xprt);
7c1d71cf	374	void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
55aa4f58	375
718ba5b8 TM	376	bool xprt_lock_connect(struct rpc_xprt , struct rpc_task , void *);
	377	void xprt_unlock_connect(struct rpc_xprt , void );
	378
2226feb6 CL	379	/*
	380	* Reserved bit positions in xprt->state
	381	*/
	382	#define XPRT_LOCKED (0)
	383	#define XPRT_CONNECTED (1)
	384	#define XPRT_CONNECTING (2)
632e3bdc	385	#define XPRT_CLOSE_WAIT (3)
ec739ef0	386	#define XPRT_BOUND (4)
4a68179d	387	#define XPRT_BINDING (5)
3b948ae5	388	#define XPRT_CLOSING (6)
ba60eb25	389	#define XPRT_CONGESTED (9)
2226feb6 CL	390
	391	static inline void xprt_set_connected(struct rpc_xprt *xprt)
	392	{
	393	set_bit(XPRT_CONNECTED, &xprt->state);
	394	}
	395
	396	static inline void xprt_clear_connected(struct rpc_xprt *xprt)
	397	{
	398	clear_bit(XPRT_CONNECTED, &xprt->state);
	399	}
	400
	401	static inline int xprt_connected(struct rpc_xprt *xprt)
	402	{
	403	return test_bit(XPRT_CONNECTED, &xprt->state);
	404	}
	405
	406	static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
	407	{
	408	return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
	409	}
	410
	411	static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
	412	{
	413	return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
	414	}
	415
	416	static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
	417	{
4e857c58	418	smp_mb__before_atomic();
2226feb6	419	clear_bit(XPRT_CONNECTING, &xprt->state);
4e857c58	420	smp_mb__after_atomic();
2226feb6 CL	421	}
	422
	423	static inline int xprt_connecting(struct rpc_xprt *xprt)
	424	{
	425	return test_bit(XPRT_CONNECTING, &xprt->state);
	426	}
	427
	428	static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
	429	{
	430	return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
	431	}
1da177e4	432
ec739ef0 CL	433	static inline void xprt_set_bound(struct rpc_xprt *xprt)
	434	{
	435	test_and_set_bit(XPRT_BOUND, &xprt->state);
	436	}
	437
	438	static inline int xprt_bound(struct rpc_xprt *xprt)
	439	{
	440	return test_bit(XPRT_BOUND, &xprt->state);
	441	}
	442
	443	static inline void xprt_clear_bound(struct rpc_xprt *xprt)
	444	{
	445	clear_bit(XPRT_BOUND, &xprt->state);
	446	}
	447
4a68179d CL	448	static inline void xprt_clear_binding(struct rpc_xprt *xprt)
4a68179d CL	449	{
4e857c58	450	smp_mb__before_atomic();
4a68179d	451	clear_bit(XPRT_BINDING, &xprt->state);
4e857c58	452	smp_mb__after_atomic();
4a68179d CL	453	}
	454
	455	static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
	456	{
	457	return test_and_set_bit(XPRT_BINDING, &xprt->state);
	458	}
	459
4a068258 CL	460	#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
	461	extern unsigned int rpc_inject_disconnect;
	462	static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)
	463	{
	464	if (!rpc_inject_disconnect)
	465	return;
	466	if (atomic_dec_return(&xprt->inject_disconnect))
	467	return;
	468	atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);
	469	xprt->ops->inject_disconnect(xprt);
	470	}
	471	#else
	472	static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)
	473	{
	474	}
	475	#endif
	476
1da177e4 LT	477	#endif /* __KERNEL__*/
	478
	479	#endif /* _LINUX_SUNRPC_XPRT_H */