xref: /openbmc/linux/net/rds/rds.h (revision fee6d4c777a125e56de9370db3b2bf359bf958d6)
1 #ifndef _RDS_RDS_H
2 #define _RDS_RDS_H
3 
4 #include <net/sock.h>
5 #include <linux/scatterlist.h>
6 #include <linux/highmem.h>
7 #include <rdma/rdma_cm.h>
8 #include <linux/mutex.h>
9 #include <linux/rds.h>
10 
11 #include "info.h"
12 
13 /*
14  * RDS Network protocol version
15  */
16 #define RDS_PROTOCOL_3_0	0x0300
17 #define RDS_PROTOCOL_3_1	0x0301
18 #define RDS_PROTOCOL_VERSION	RDS_PROTOCOL_3_1
19 #define RDS_PROTOCOL_MAJOR(v)	((v) >> 8)
20 #define RDS_PROTOCOL_MINOR(v)	((v) & 255)
21 #define RDS_PROTOCOL(maj, min)	(((maj) << 8) | min)
22 
23 /*
24  * XXX randomly chosen, but at least seems to be unused:
25  * #               18464-18768 Unassigned
26  * We should do better.  We want a reserved port to discourage unpriv'ed
27  * userspace from listening.
28  */
29 #define RDS_PORT	18634
30 
31 #ifdef ATOMIC64_INIT
32 #define KERNEL_HAS_ATOMIC64
33 #endif
34 
35 #ifdef DEBUG
36 #define rdsdebug(fmt, args...) pr_debug("%s(): " fmt, __func__ , ##args)
37 #else
38 /* sigh, pr_debug() causes unused variable warnings */
39 static inline __printf(1, 2)
40 void rdsdebug(char *fmt, ...)
41 {
42 }
43 #endif
44 
45 /* XXX is there one of these somewhere? */
46 #define ceil(x, y) \
47 	({ unsigned long __x = (x), __y = (y); (__x + __y - 1) / __y; })
48 
49 #define RDS_FRAG_SHIFT	12
50 #define RDS_FRAG_SIZE	((unsigned int)(1 << RDS_FRAG_SHIFT))
51 
52 #define RDS_CONG_MAP_BYTES	(65536 / 8)
53 #define RDS_CONG_MAP_PAGES	(PAGE_ALIGN(RDS_CONG_MAP_BYTES) / PAGE_SIZE)
54 #define RDS_CONG_MAP_PAGE_BITS	(PAGE_SIZE * 8)
55 
56 struct rds_cong_map {
57 	struct rb_node		m_rb_node;
58 	__be32			m_addr;
59 	wait_queue_head_t	m_waitq;
60 	struct list_head	m_conn_list;
61 	unsigned long		m_page_addrs[RDS_CONG_MAP_PAGES];
62 };
63 
64 
65 /*
66  * This is how we will track the connection state:
67  * A connection is always in one of the following
68  * states. Updates to the state are atomic and imply
69  * a memory barrier.
70  */
71 enum {
72 	RDS_CONN_DOWN = 0,
73 	RDS_CONN_CONNECTING,
74 	RDS_CONN_DISCONNECTING,
75 	RDS_CONN_UP,
76 	RDS_CONN_ERROR,
77 };
78 
79 /* Bits for c_flags */
80 #define RDS_LL_SEND_FULL	0
81 #define RDS_RECONNECT_PENDING	1
82 #define RDS_IN_XMIT		2
83 #define RDS_RECV_REFILL		3
84 
85 struct rds_connection {
86 	struct hlist_node	c_hash_node;
87 	__be32			c_laddr;
88 	__be32			c_faddr;
89 	unsigned int		c_loopback:1,
90 				c_outgoing:1,
91 				c_pad_to_32:30;
92 	struct rds_connection	*c_passive;
93 
94 	struct rds_cong_map	*c_lcong;
95 	struct rds_cong_map	*c_fcong;
96 
97 	struct rds_message	*c_xmit_rm;
98 	unsigned long		c_xmit_sg;
99 	unsigned int		c_xmit_hdr_off;
100 	unsigned int		c_xmit_data_off;
101 	unsigned int		c_xmit_atomic_sent;
102 	unsigned int		c_xmit_rdma_sent;
103 	unsigned int		c_xmit_data_sent;
104 
105 	spinlock_t		c_lock;		/* protect msg queues */
106 	u64			c_next_tx_seq;
107 	struct list_head	c_send_queue;
108 	struct list_head	c_retrans;
109 
110 	u64			c_next_rx_seq;
111 
112 	struct rds_transport	*c_trans;
113 	void			*c_transport_data;
114 
115 	atomic_t		c_state;
116 	unsigned long		c_send_gen;
117 	unsigned long		c_flags;
118 	unsigned long		c_reconnect_jiffies;
119 	struct delayed_work	c_send_w;
120 	struct delayed_work	c_recv_w;
121 	struct delayed_work	c_conn_w;
122 	struct work_struct	c_down_w;
123 	struct mutex		c_cm_lock;	/* protect conn state & cm */
124 	wait_queue_head_t	c_waitq;
125 
126 	struct list_head	c_map_item;
127 	unsigned long		c_map_queued;
128 
129 	unsigned int		c_unacked_packets;
130 	unsigned int		c_unacked_bytes;
131 
132 	/* Protocol version */
133 	unsigned int		c_version;
134 	possible_net_t		c_net;
135 };
136 
137 static inline
138 struct net *rds_conn_net(struct rds_connection *conn)
139 {
140 	return read_pnet(&conn->c_net);
141 }
142 
143 static inline
144 void rds_conn_net_set(struct rds_connection *conn, struct net *net)
145 {
146 	write_pnet(&conn->c_net, net);
147 }
148 
149 #define RDS_FLAG_CONG_BITMAP	0x01
150 #define RDS_FLAG_ACK_REQUIRED	0x02
151 #define RDS_FLAG_RETRANSMITTED	0x04
152 #define RDS_MAX_ADV_CREDIT	255
153 
154 /*
155  * Maximum space available for extension headers.
156  */
157 #define RDS_HEADER_EXT_SPACE	16
158 
159 struct rds_header {
160 	__be64	h_sequence;
161 	__be64	h_ack;
162 	__be32	h_len;
163 	__be16	h_sport;
164 	__be16	h_dport;
165 	u8	h_flags;
166 	u8	h_credit;
167 	u8	h_padding[4];
168 	__sum16	h_csum;
169 
170 	u8	h_exthdr[RDS_HEADER_EXT_SPACE];
171 };
172 
173 /*
174  * Reserved - indicates end of extensions
175  */
176 #define RDS_EXTHDR_NONE		0
177 
178 /*
179  * This extension header is included in the very
180  * first message that is sent on a new connection,
181  * and identifies the protocol level. This will help
182  * rolling updates if a future change requires breaking
183  * the protocol.
184  * NB: This is no longer true for IB, where we do a version
185  * negotiation during the connection setup phase (protocol
186  * version information is included in the RDMA CM private data).
187  */
188 #define RDS_EXTHDR_VERSION	1
189 struct rds_ext_header_version {
190 	__be32			h_version;
191 };
192 
193 /*
194  * This extension header is included in the RDS message
195  * chasing an RDMA operation.
196  */
197 #define RDS_EXTHDR_RDMA		2
198 struct rds_ext_header_rdma {
199 	__be32			h_rdma_rkey;
200 };
201 
202 /*
203  * This extension header tells the peer about the
204  * destination <R_Key,offset> of the requested RDMA
205  * operation.
206  */
207 #define RDS_EXTHDR_RDMA_DEST	3
208 struct rds_ext_header_rdma_dest {
209 	__be32			h_rdma_rkey;
210 	__be32			h_rdma_offset;
211 };
212 
213 #define __RDS_EXTHDR_MAX	16 /* for now */
214 
215 struct rds_incoming {
216 	atomic_t		i_refcount;
217 	struct list_head	i_item;
218 	struct rds_connection	*i_conn;
219 	struct rds_header	i_hdr;
220 	unsigned long		i_rx_jiffies;
221 	__be32			i_saddr;
222 
223 	rds_rdma_cookie_t	i_rdma_cookie;
224 };
225 
226 struct rds_mr {
227 	struct rb_node		r_rb_node;
228 	atomic_t		r_refcount;
229 	u32			r_key;
230 
231 	/* A copy of the creation flags */
232 	unsigned int		r_use_once:1;
233 	unsigned int		r_invalidate:1;
234 	unsigned int		r_write:1;
235 
236 	/* This is for RDS_MR_DEAD.
237 	 * It would be nice & consistent to make this part of the above
238 	 * bit field here, but we need to use test_and_set_bit.
239 	 */
240 	unsigned long		r_state;
241 	struct rds_sock		*r_sock; /* back pointer to the socket that owns us */
242 	struct rds_transport	*r_trans;
243 	void			*r_trans_private;
244 };
245 
246 /* Flags for mr->r_state */
247 #define RDS_MR_DEAD		0
248 
249 static inline rds_rdma_cookie_t rds_rdma_make_cookie(u32 r_key, u32 offset)
250 {
251 	return r_key | (((u64) offset) << 32);
252 }
253 
254 static inline u32 rds_rdma_cookie_key(rds_rdma_cookie_t cookie)
255 {
256 	return cookie;
257 }
258 
259 static inline u32 rds_rdma_cookie_offset(rds_rdma_cookie_t cookie)
260 {
261 	return cookie >> 32;
262 }
263 
264 /* atomic operation types */
265 #define RDS_ATOMIC_TYPE_CSWP		0
266 #define RDS_ATOMIC_TYPE_FADD		1
267 
268 /*
269  * m_sock_item and m_conn_item are on lists that are serialized under
270  * conn->c_lock.  m_sock_item has additional meaning in that once it is empty
271  * the message will not be put back on the retransmit list after being sent.
272  * messages that are canceled while being sent rely on this.
273  *
274  * m_inc is used by loopback so that it can pass an incoming message straight
275  * back up into the rx path.  It embeds a wire header which is also used by
276  * the send path, which is kind of awkward.
277  *
278  * m_sock_item indicates the message's presence on a socket's send or receive
279  * queue.  m_rs will point to that socket.
280  *
281  * m_daddr is used by cancellation to prune messages to a given destination.
282  *
283  * The RDS_MSG_ON_SOCK and RDS_MSG_ON_CONN flags are used to avoid lock
284  * nesting.  As paths iterate over messages on a sock, or conn, they must
285  * also lock the conn, or sock, to remove the message from those lists too.
286  * Testing the flag to determine if the message is still on the lists lets
287  * us avoid testing the list_head directly.  That means each path can use
288  * the message's list_head to keep it on a local list while juggling locks
289  * without confusing the other path.
290  *
291  * m_ack_seq is an optional field set by transports who need a different
292  * sequence number range to invalidate.  They can use this in a callback
293  * that they pass to rds_send_drop_acked() to see if each message has been
294  * acked.  The HAS_ACK_SEQ flag can be used to detect messages which haven't
295  * had ack_seq set yet.
296  */
297 #define RDS_MSG_ON_SOCK		1
298 #define RDS_MSG_ON_CONN		2
299 #define RDS_MSG_HAS_ACK_SEQ	3
300 #define RDS_MSG_ACK_REQUIRED	4
301 #define RDS_MSG_RETRANSMITTED	5
302 #define RDS_MSG_MAPPED		6
303 #define RDS_MSG_PAGEVEC		7
304 
305 struct rds_message {
306 	atomic_t		m_refcount;
307 	struct list_head	m_sock_item;
308 	struct list_head	m_conn_item;
309 	struct rds_incoming	m_inc;
310 	u64			m_ack_seq;
311 	__be32			m_daddr;
312 	unsigned long		m_flags;
313 
314 	/* Never access m_rs without holding m_rs_lock.
315 	 * Lock nesting is
316 	 *  rm->m_rs_lock
317 	 *   -> rs->rs_lock
318 	 */
319 	spinlock_t		m_rs_lock;
320 	wait_queue_head_t	m_flush_wait;
321 
322 	struct rds_sock		*m_rs;
323 
324 	/* cookie to send to remote, in rds header */
325 	rds_rdma_cookie_t	m_rdma_cookie;
326 
327 	unsigned int		m_used_sgs;
328 	unsigned int		m_total_sgs;
329 
330 	void			*m_final_op;
331 
332 	struct {
333 		struct rm_atomic_op {
334 			int			op_type;
335 			union {
336 				struct {
337 					uint64_t	compare;
338 					uint64_t	swap;
339 					uint64_t	compare_mask;
340 					uint64_t	swap_mask;
341 				} op_m_cswp;
342 				struct {
343 					uint64_t	add;
344 					uint64_t	nocarry_mask;
345 				} op_m_fadd;
346 			};
347 
348 			u32			op_rkey;
349 			u64			op_remote_addr;
350 			unsigned int		op_notify:1;
351 			unsigned int		op_recverr:1;
352 			unsigned int		op_mapped:1;
353 			unsigned int		op_silent:1;
354 			unsigned int		op_active:1;
355 			struct scatterlist	*op_sg;
356 			struct rds_notifier	*op_notifier;
357 
358 			struct rds_mr		*op_rdma_mr;
359 		} atomic;
360 		struct rm_rdma_op {
361 			u32			op_rkey;
362 			u64			op_remote_addr;
363 			unsigned int		op_write:1;
364 			unsigned int		op_fence:1;
365 			unsigned int		op_notify:1;
366 			unsigned int		op_recverr:1;
367 			unsigned int		op_mapped:1;
368 			unsigned int		op_silent:1;
369 			unsigned int		op_active:1;
370 			unsigned int		op_bytes;
371 			unsigned int		op_nents;
372 			unsigned int		op_count;
373 			struct scatterlist	*op_sg;
374 			struct rds_notifier	*op_notifier;
375 
376 			struct rds_mr		*op_rdma_mr;
377 		} rdma;
378 		struct rm_data_op {
379 			unsigned int		op_active:1;
380 			unsigned int		op_nents;
381 			unsigned int		op_count;
382 			unsigned int		op_dmasg;
383 			unsigned int		op_dmaoff;
384 			struct scatterlist	*op_sg;
385 		} data;
386 	};
387 };
388 
389 /*
390  * The RDS notifier is used (optionally) to tell the application about
391  * completed RDMA operations. Rather than keeping the whole rds message
392  * around on the queue, we allocate a small notifier that is put on the
393  * socket's notifier_list. Notifications are delivered to the application
394  * through control messages.
395  */
396 struct rds_notifier {
397 	struct list_head	n_list;
398 	uint64_t		n_user_token;
399 	int			n_status;
400 };
401 
402 /**
403  * struct rds_transport -  transport specific behavioural hooks
404  *
405  * @xmit: .xmit is called by rds_send_xmit() to tell the transport to send
406  *        part of a message.  The caller serializes on the send_sem so this
407  *        doesn't need to be reentrant for a given conn.  The header must be
408  *        sent before the data payload.  .xmit must be prepared to send a
409  *        message with no data payload.  .xmit should return the number of
410  *        bytes that were sent down the connection, including header bytes.
411  *        Returning 0 tells the caller that it doesn't need to perform any
412  *        additional work now.  This is usually the case when the transport has
413  *        filled the sending queue for its connection and will handle
414  *        triggering the rds thread to continue the send when space becomes
415  *        available.  Returning -EAGAIN tells the caller to retry the send
416  *        immediately.  Returning -ENOMEM tells the caller to retry the send at
417  *        some point in the future.
418  *
419  * @conn_shutdown: conn_shutdown stops traffic on the given connection.  Once
420  *                 it returns the connection can not call rds_recv_incoming().
421  *                 This will only be called once after conn_connect returns
422  *                 non-zero success and will The caller serializes this with
423  *                 the send and connecting paths (xmit_* and conn_*).  The
424  *                 transport is responsible for other serialization, including
425  *                 rds_recv_incoming().  This is called in process context but
426  *                 should try hard not to block.
427  */
428 
429 struct rds_transport {
430 	char			t_name[TRANSNAMSIZ];
431 	struct list_head	t_item;
432 	struct module		*t_owner;
433 	unsigned int		t_prefer_loopback:1;
434 	unsigned int		t_type;
435 
436 	int (*laddr_check)(struct net *net, __be32 addr);
437 	int (*conn_alloc)(struct rds_connection *conn, gfp_t gfp);
438 	void (*conn_free)(void *data);
439 	int (*conn_connect)(struct rds_connection *conn);
440 	void (*conn_shutdown)(struct rds_connection *conn);
441 	void (*xmit_prepare)(struct rds_connection *conn);
442 	void (*xmit_complete)(struct rds_connection *conn);
443 	int (*xmit)(struct rds_connection *conn, struct rds_message *rm,
444 		    unsigned int hdr_off, unsigned int sg, unsigned int off);
445 	int (*xmit_rdma)(struct rds_connection *conn, struct rm_rdma_op *op);
446 	int (*xmit_atomic)(struct rds_connection *conn, struct rm_atomic_op *op);
447 	int (*recv)(struct rds_connection *conn);
448 	int (*inc_copy_to_user)(struct rds_incoming *inc, struct iov_iter *to);
449 	void (*inc_free)(struct rds_incoming *inc);
450 
451 	int (*cm_handle_connect)(struct rdma_cm_id *cm_id,
452 				 struct rdma_cm_event *event);
453 	int (*cm_initiate_connect)(struct rdma_cm_id *cm_id);
454 	void (*cm_connect_complete)(struct rds_connection *conn,
455 				    struct rdma_cm_event *event);
456 
457 	unsigned int (*stats_info_copy)(struct rds_info_iterator *iter,
458 					unsigned int avail);
459 	void (*exit)(void);
460 	void *(*get_mr)(struct scatterlist *sg, unsigned long nr_sg,
461 			struct rds_sock *rs, u32 *key_ret);
462 	void (*sync_mr)(void *trans_private, int direction);
463 	void (*free_mr)(void *trans_private, int invalidate);
464 	void (*flush_mrs)(void);
465 };
466 
467 struct rds_sock {
468 	struct sock		rs_sk;
469 
470 	u64			rs_user_addr;
471 	u64			rs_user_bytes;
472 
473 	/*
474 	 * bound_addr used for both incoming and outgoing, no INADDR_ANY
475 	 * support.
476 	 */
477 	struct hlist_node	rs_bound_node;
478 	__be32			rs_bound_addr;
479 	__be32			rs_conn_addr;
480 	__be16			rs_bound_port;
481 	__be16			rs_conn_port;
482 	struct rds_transport    *rs_transport;
483 
484 	/*
485 	 * rds_sendmsg caches the conn it used the last time around.
486 	 * This helps avoid costly lookups.
487 	 */
488 	struct rds_connection	*rs_conn;
489 
490 	/* flag indicating we were congested or not */
491 	int			rs_congested;
492 	/* seen congestion (ENOBUFS) when sending? */
493 	int			rs_seen_congestion;
494 
495 	/* rs_lock protects all these adjacent members before the newline */
496 	spinlock_t		rs_lock;
497 	struct list_head	rs_send_queue;
498 	u32			rs_snd_bytes;
499 	int			rs_rcv_bytes;
500 	struct list_head	rs_notify_queue;	/* currently used for failed RDMAs */
501 
502 	/* Congestion wake_up. If rs_cong_monitor is set, we use cong_mask
503 	 * to decide whether the application should be woken up.
504 	 * If not set, we use rs_cong_track to find out whether a cong map
505 	 * update arrived.
506 	 */
507 	uint64_t		rs_cong_mask;
508 	uint64_t		rs_cong_notify;
509 	struct list_head	rs_cong_list;
510 	unsigned long		rs_cong_track;
511 
512 	/*
513 	 * rs_recv_lock protects the receive queue, and is
514 	 * used to serialize with rds_release.
515 	 */
516 	rwlock_t		rs_recv_lock;
517 	struct list_head	rs_recv_queue;
518 
519 	/* just for stats reporting */
520 	struct list_head	rs_item;
521 
522 	/* these have their own lock */
523 	spinlock_t		rs_rdma_lock;
524 	struct rb_root		rs_rdma_keys;
525 
526 	/* Socket options - in case there will be more */
527 	unsigned char		rs_recverr,
528 				rs_cong_monitor;
529 };
530 
531 static inline struct rds_sock *rds_sk_to_rs(const struct sock *sk)
532 {
533 	return container_of(sk, struct rds_sock, rs_sk);
534 }
535 static inline struct sock *rds_rs_to_sk(struct rds_sock *rs)
536 {
537 	return &rs->rs_sk;
538 }
539 
540 /*
541  * The stack assigns sk_sndbuf and sk_rcvbuf to twice the specified value
542  * to account for overhead.  We don't account for overhead, we just apply
543  * the number of payload bytes to the specified value.
544  */
545 static inline int rds_sk_sndbuf(struct rds_sock *rs)
546 {
547 	return rds_rs_to_sk(rs)->sk_sndbuf / 2;
548 }
549 static inline int rds_sk_rcvbuf(struct rds_sock *rs)
550 {
551 	return rds_rs_to_sk(rs)->sk_rcvbuf / 2;
552 }
553 
554 struct rds_statistics {
555 	uint64_t	s_conn_reset;
556 	uint64_t	s_recv_drop_bad_checksum;
557 	uint64_t	s_recv_drop_old_seq;
558 	uint64_t	s_recv_drop_no_sock;
559 	uint64_t	s_recv_drop_dead_sock;
560 	uint64_t	s_recv_deliver_raced;
561 	uint64_t	s_recv_delivered;
562 	uint64_t	s_recv_queued;
563 	uint64_t	s_recv_immediate_retry;
564 	uint64_t	s_recv_delayed_retry;
565 	uint64_t	s_recv_ack_required;
566 	uint64_t	s_recv_rdma_bytes;
567 	uint64_t	s_recv_ping;
568 	uint64_t	s_send_queue_empty;
569 	uint64_t	s_send_queue_full;
570 	uint64_t	s_send_lock_contention;
571 	uint64_t	s_send_lock_queue_raced;
572 	uint64_t	s_send_immediate_retry;
573 	uint64_t	s_send_delayed_retry;
574 	uint64_t	s_send_drop_acked;
575 	uint64_t	s_send_ack_required;
576 	uint64_t	s_send_queued;
577 	uint64_t	s_send_rdma;
578 	uint64_t	s_send_rdma_bytes;
579 	uint64_t	s_send_pong;
580 	uint64_t	s_page_remainder_hit;
581 	uint64_t	s_page_remainder_miss;
582 	uint64_t	s_copy_to_user;
583 	uint64_t	s_copy_from_user;
584 	uint64_t	s_cong_update_queued;
585 	uint64_t	s_cong_update_received;
586 	uint64_t	s_cong_send_error;
587 	uint64_t	s_cong_send_blocked;
588 };
589 
590 /* af_rds.c */
591 void rds_sock_addref(struct rds_sock *rs);
592 void rds_sock_put(struct rds_sock *rs);
593 void rds_wake_sk_sleep(struct rds_sock *rs);
594 static inline void __rds_wake_sk_sleep(struct sock *sk)
595 {
596 	wait_queue_head_t *waitq = sk_sleep(sk);
597 
598 	if (!sock_flag(sk, SOCK_DEAD) && waitq)
599 		wake_up(waitq);
600 }
601 extern wait_queue_head_t rds_poll_waitq;
602 
603 
604 /* bind.c */
605 int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
606 void rds_remove_bound(struct rds_sock *rs);
607 struct rds_sock *rds_find_bound(__be32 addr, __be16 port);
608 
609 /* cong.c */
610 int rds_cong_get_maps(struct rds_connection *conn);
611 void rds_cong_add_conn(struct rds_connection *conn);
612 void rds_cong_remove_conn(struct rds_connection *conn);
613 void rds_cong_set_bit(struct rds_cong_map *map, __be16 port);
614 void rds_cong_clear_bit(struct rds_cong_map *map, __be16 port);
615 int rds_cong_wait(struct rds_cong_map *map, __be16 port, int nonblock, struct rds_sock *rs);
616 void rds_cong_queue_updates(struct rds_cong_map *map);
617 void rds_cong_map_updated(struct rds_cong_map *map, uint64_t);
618 int rds_cong_updated_since(unsigned long *recent);
619 void rds_cong_add_socket(struct rds_sock *);
620 void rds_cong_remove_socket(struct rds_sock *);
621 void rds_cong_exit(void);
622 struct rds_message *rds_cong_update_alloc(struct rds_connection *conn);
623 
624 /* conn.c */
625 int rds_conn_init(void);
626 void rds_conn_exit(void);
627 struct rds_connection *rds_conn_create(struct net *net,
628 				       __be32 laddr, __be32 faddr,
629 				       struct rds_transport *trans, gfp_t gfp);
630 struct rds_connection *rds_conn_create_outgoing(struct net *net,
631 						__be32 laddr, __be32 faddr,
632 			       struct rds_transport *trans, gfp_t gfp);
633 void rds_conn_shutdown(struct rds_connection *conn);
634 void rds_conn_destroy(struct rds_connection *conn);
635 void rds_conn_drop(struct rds_connection *conn);
636 void rds_conn_connect_if_down(struct rds_connection *conn);
637 void rds_for_each_conn_info(struct socket *sock, unsigned int len,
638 			  struct rds_info_iterator *iter,
639 			  struct rds_info_lengths *lens,
640 			  int (*visitor)(struct rds_connection *, void *),
641 			  size_t item_len);
642 __printf(2, 3)
643 void __rds_conn_error(struct rds_connection *conn, const char *, ...);
644 #define rds_conn_error(conn, fmt...) \
645 	__rds_conn_error(conn, KERN_WARNING "RDS: " fmt)
646 
647 static inline int
648 rds_conn_transition(struct rds_connection *conn, int old, int new)
649 {
650 	return atomic_cmpxchg(&conn->c_state, old, new) == old;
651 }
652 
653 static inline int
654 rds_conn_state(struct rds_connection *conn)
655 {
656 	return atomic_read(&conn->c_state);
657 }
658 
659 static inline int
660 rds_conn_up(struct rds_connection *conn)
661 {
662 	return atomic_read(&conn->c_state) == RDS_CONN_UP;
663 }
664 
665 static inline int
666 rds_conn_connecting(struct rds_connection *conn)
667 {
668 	return atomic_read(&conn->c_state) == RDS_CONN_CONNECTING;
669 }
670 
671 /* message.c */
672 struct rds_message *rds_message_alloc(unsigned int nents, gfp_t gfp);
673 struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents);
674 int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from);
675 struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len);
676 void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
677 				 __be16 dport, u64 seq);
678 int rds_message_add_extension(struct rds_header *hdr,
679 			      unsigned int type, const void *data, unsigned int len);
680 int rds_message_next_extension(struct rds_header *hdr,
681 			       unsigned int *pos, void *buf, unsigned int *buflen);
682 int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset);
683 int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
684 void rds_message_inc_free(struct rds_incoming *inc);
685 void rds_message_addref(struct rds_message *rm);
686 void rds_message_put(struct rds_message *rm);
687 void rds_message_wait(struct rds_message *rm);
688 void rds_message_unmapped(struct rds_message *rm);
689 
690 static inline void rds_message_make_checksum(struct rds_header *hdr)
691 {
692 	hdr->h_csum = 0;
693 	hdr->h_csum = ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2);
694 }
695 
696 static inline int rds_message_verify_checksum(const struct rds_header *hdr)
697 {
698 	return !hdr->h_csum || ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2) == 0;
699 }
700 
701 
702 /* page.c */
703 int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes,
704 			     gfp_t gfp);
705 int rds_page_copy_user(struct page *page, unsigned long offset,
706 		       void __user *ptr, unsigned long bytes,
707 		       int to_user);
708 #define rds_page_copy_to_user(page, offset, ptr, bytes) \
709 	rds_page_copy_user(page, offset, ptr, bytes, 1)
710 #define rds_page_copy_from_user(page, offset, ptr, bytes) \
711 	rds_page_copy_user(page, offset, ptr, bytes, 0)
712 void rds_page_exit(void);
713 
714 /* recv.c */
715 void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
716 		  __be32 saddr);
717 void rds_inc_put(struct rds_incoming *inc);
718 void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr,
719 		       struct rds_incoming *inc, gfp_t gfp);
720 int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
721 		int msg_flags);
722 void rds_clear_recv_queue(struct rds_sock *rs);
723 int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msg);
724 void rds_inc_info_copy(struct rds_incoming *inc,
725 		       struct rds_info_iterator *iter,
726 		       __be32 saddr, __be32 daddr, int flip);
727 
728 /* send.c */
729 int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len);
730 void rds_send_reset(struct rds_connection *conn);
731 int rds_send_xmit(struct rds_connection *conn);
732 struct sockaddr_in;
733 void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest);
734 typedef int (*is_acked_func)(struct rds_message *rm, uint64_t ack);
735 void rds_send_drop_acked(struct rds_connection *conn, u64 ack,
736 			 is_acked_func is_acked);
737 int rds_send_pong(struct rds_connection *conn, __be16 dport);
738 struct rds_message *rds_send_get_message(struct rds_connection *,
739 					 struct rm_rdma_op *);
740 
741 /* rdma.c */
742 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force);
743 int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen);
744 int rds_get_mr_for_dest(struct rds_sock *rs, char __user *optval, int optlen);
745 int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen);
746 void rds_rdma_drop_keys(struct rds_sock *rs);
747 int rds_rdma_extra_size(struct rds_rdma_args *args);
748 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
749 			  struct cmsghdr *cmsg);
750 int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm,
751 			  struct cmsghdr *cmsg);
752 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
753 			  struct cmsghdr *cmsg);
754 int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm,
755 			  struct cmsghdr *cmsg);
756 void rds_rdma_free_op(struct rm_rdma_op *ro);
757 void rds_atomic_free_op(struct rm_atomic_op *ao);
758 void rds_rdma_send_complete(struct rds_message *rm, int wc_status);
759 void rds_atomic_send_complete(struct rds_message *rm, int wc_status);
760 int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm,
761 		    struct cmsghdr *cmsg);
762 
763 void __rds_put_mr_final(struct rds_mr *mr);
764 static inline void rds_mr_put(struct rds_mr *mr)
765 {
766 	if (atomic_dec_and_test(&mr->r_refcount))
767 		__rds_put_mr_final(mr);
768 }
769 
770 /* stats.c */
771 DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_statistics, rds_stats);
772 #define rds_stats_inc_which(which, member) do {		\
773 	per_cpu(which, get_cpu()).member++;		\
774 	put_cpu();					\
775 } while (0)
776 #define rds_stats_inc(member) rds_stats_inc_which(rds_stats, member)
777 #define rds_stats_add_which(which, member, count) do {		\
778 	per_cpu(which, get_cpu()).member += count;	\
779 	put_cpu();					\
780 } while (0)
781 #define rds_stats_add(member, count) rds_stats_add_which(rds_stats, member, count)
782 int rds_stats_init(void);
783 void rds_stats_exit(void);
784 void rds_stats_info_copy(struct rds_info_iterator *iter,
785 			 uint64_t *values, const char *const *names,
786 			 size_t nr);
787 
788 /* sysctl.c */
789 int rds_sysctl_init(void);
790 void rds_sysctl_exit(void);
791 extern unsigned long rds_sysctl_sndbuf_min;
792 extern unsigned long rds_sysctl_sndbuf_default;
793 extern unsigned long rds_sysctl_sndbuf_max;
794 extern unsigned long rds_sysctl_reconnect_min_jiffies;
795 extern unsigned long rds_sysctl_reconnect_max_jiffies;
796 extern unsigned int  rds_sysctl_max_unacked_packets;
797 extern unsigned int  rds_sysctl_max_unacked_bytes;
798 extern unsigned int  rds_sysctl_ping_enable;
799 extern unsigned long rds_sysctl_trace_flags;
800 extern unsigned int  rds_sysctl_trace_level;
801 
802 /* threads.c */
803 int rds_threads_init(void);
804 void rds_threads_exit(void);
805 extern struct workqueue_struct *rds_wq;
806 void rds_queue_reconnect(struct rds_connection *conn);
807 void rds_connect_worker(struct work_struct *);
808 void rds_shutdown_worker(struct work_struct *);
809 void rds_send_worker(struct work_struct *);
810 void rds_recv_worker(struct work_struct *);
811 void rds_connect_complete(struct rds_connection *conn);
812 
813 /* transport.c */
814 int rds_trans_register(struct rds_transport *trans);
815 void rds_trans_unregister(struct rds_transport *trans);
816 struct rds_transport *rds_trans_get_preferred(struct net *net, __be32 addr);
817 void rds_trans_put(struct rds_transport *trans);
818 unsigned int rds_trans_stats_info_copy(struct rds_info_iterator *iter,
819 				       unsigned int avail);
820 struct rds_transport *rds_trans_get(int t_type);
821 int rds_trans_init(void);
822 void rds_trans_exit(void);
823 
824 #endif
825