xref: /linux/net/rds/rds.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 
84 struct rds_connection {
85 	struct hlist_node	c_hash_node;
86 	__be32			c_laddr;
87 	__be32			c_faddr;
88 	unsigned int		c_loopback:1;
89 	struct rds_connection	*c_passive;
90 
91 	struct rds_cong_map	*c_lcong;
92 	struct rds_cong_map	*c_fcong;
93 
94 	struct rds_message	*c_xmit_rm;
95 	unsigned long		c_xmit_sg;
96 	unsigned int		c_xmit_hdr_off;
97 	unsigned int		c_xmit_data_off;
98 	unsigned int		c_xmit_atomic_sent;
99 	unsigned int		c_xmit_rdma_sent;
100 	unsigned int		c_xmit_data_sent;
101 
102 	spinlock_t		c_lock;		/* protect msg queues */
103 	u64			c_next_tx_seq;
104 	struct list_head	c_send_queue;
105 	struct list_head	c_retrans;
106 
107 	u64			c_next_rx_seq;
108 
109 	struct rds_transport	*c_trans;
110 	void			*c_transport_data;
111 
112 	atomic_t		c_state;
113 	unsigned long		c_flags;
114 	unsigned long		c_reconnect_jiffies;
115 	struct delayed_work	c_send_w;
116 	struct delayed_work	c_recv_w;
117 	struct delayed_work	c_conn_w;
118 	struct work_struct	c_down_w;
119 	struct mutex		c_cm_lock;	/* protect conn state & cm */
120 	wait_queue_head_t	c_waitq;
121 
122 	struct list_head	c_map_item;
123 	unsigned long		c_map_queued;
124 
125 	unsigned int		c_unacked_packets;
126 	unsigned int		c_unacked_bytes;
127 
128 	/* Protocol version */
129 	unsigned int		c_version;
130 };
131 
132 #define RDS_FLAG_CONG_BITMAP	0x01
133 #define RDS_FLAG_ACK_REQUIRED	0x02
134 #define RDS_FLAG_RETRANSMITTED	0x04
135 #define RDS_MAX_ADV_CREDIT	255
136 
137 /*
138  * Maximum space available for extension headers.
139  */
140 #define RDS_HEADER_EXT_SPACE	16
141 
142 struct rds_header {
143 	__be64	h_sequence;
144 	__be64	h_ack;
145 	__be32	h_len;
146 	__be16	h_sport;
147 	__be16	h_dport;
148 	u8	h_flags;
149 	u8	h_credit;
150 	u8	h_padding[4];
151 	__sum16	h_csum;
152 
153 	u8	h_exthdr[RDS_HEADER_EXT_SPACE];
154 };
155 
156 /*
157  * Reserved - indicates end of extensions
158  */
159 #define RDS_EXTHDR_NONE		0
160 
161 /*
162  * This extension header is included in the very
163  * first message that is sent on a new connection,
164  * and identifies the protocol level. This will help
165  * rolling updates if a future change requires breaking
166  * the protocol.
167  * NB: This is no longer true for IB, where we do a version
168  * negotiation during the connection setup phase (protocol
169  * version information is included in the RDMA CM private data).
170  */
171 #define RDS_EXTHDR_VERSION	1
172 struct rds_ext_header_version {
173 	__be32			h_version;
174 };
175 
176 /*
177  * This extension header is included in the RDS message
178  * chasing an RDMA operation.
179  */
180 #define RDS_EXTHDR_RDMA		2
181 struct rds_ext_header_rdma {
182 	__be32			h_rdma_rkey;
183 };
184 
185 /*
186  * This extension header tells the peer about the
187  * destination <R_Key,offset> of the requested RDMA
188  * operation.
189  */
190 #define RDS_EXTHDR_RDMA_DEST	3
191 struct rds_ext_header_rdma_dest {
192 	__be32			h_rdma_rkey;
193 	__be32			h_rdma_offset;
194 };
195 
196 #define __RDS_EXTHDR_MAX	16 /* for now */
197 
198 struct rds_incoming {
199 	atomic_t		i_refcount;
200 	struct list_head	i_item;
201 	struct rds_connection	*i_conn;
202 	struct rds_header	i_hdr;
203 	unsigned long		i_rx_jiffies;
204 	__be32			i_saddr;
205 
206 	rds_rdma_cookie_t	i_rdma_cookie;
207 };
208 
209 struct rds_mr {
210 	struct rb_node		r_rb_node;
211 	atomic_t		r_refcount;
212 	u32			r_key;
213 
214 	/* A copy of the creation flags */
215 	unsigned int		r_use_once:1;
216 	unsigned int		r_invalidate:1;
217 	unsigned int		r_write:1;
218 
219 	/* This is for RDS_MR_DEAD.
220 	 * It would be nice & consistent to make this part of the above
221 	 * bit field here, but we need to use test_and_set_bit.
222 	 */
223 	unsigned long		r_state;
224 	struct rds_sock		*r_sock; /* back pointer to the socket that owns us */
225 	struct rds_transport	*r_trans;
226 	void			*r_trans_private;
227 };
228 
229 /* Flags for mr->r_state */
230 #define RDS_MR_DEAD		0
231 
232 static inline rds_rdma_cookie_t rds_rdma_make_cookie(u32 r_key, u32 offset)
233 {
234 	return r_key | (((u64) offset) << 32);
235 }
236 
237 static inline u32 rds_rdma_cookie_key(rds_rdma_cookie_t cookie)
238 {
239 	return cookie;
240 }
241 
242 static inline u32 rds_rdma_cookie_offset(rds_rdma_cookie_t cookie)
243 {
244 	return cookie >> 32;
245 }
246 
247 /* atomic operation types */
248 #define RDS_ATOMIC_TYPE_CSWP		0
249 #define RDS_ATOMIC_TYPE_FADD		1
250 
251 /*
252  * m_sock_item and m_conn_item are on lists that are serialized under
253  * conn->c_lock.  m_sock_item has additional meaning in that once it is empty
254  * the message will not be put back on the retransmit list after being sent.
255  * messages that are canceled while being sent rely on this.
256  *
257  * m_inc is used by loopback so that it can pass an incoming message straight
258  * back up into the rx path.  It embeds a wire header which is also used by
259  * the send path, which is kind of awkward.
260  *
261  * m_sock_item indicates the message's presence on a socket's send or receive
262  * queue.  m_rs will point to that socket.
263  *
264  * m_daddr is used by cancellation to prune messages to a given destination.
265  *
266  * The RDS_MSG_ON_SOCK and RDS_MSG_ON_CONN flags are used to avoid lock
267  * nesting.  As paths iterate over messages on a sock, or conn, they must
268  * also lock the conn, or sock, to remove the message from those lists too.
269  * Testing the flag to determine if the message is still on the lists lets
270  * us avoid testing the list_head directly.  That means each path can use
271  * the message's list_head to keep it on a local list while juggling locks
272  * without confusing the other path.
273  *
274  * m_ack_seq is an optional field set by transports who need a different
275  * sequence number range to invalidate.  They can use this in a callback
276  * that they pass to rds_send_drop_acked() to see if each message has been
277  * acked.  The HAS_ACK_SEQ flag can be used to detect messages which haven't
278  * had ack_seq set yet.
279  */
280 #define RDS_MSG_ON_SOCK		1
281 #define RDS_MSG_ON_CONN		2
282 #define RDS_MSG_HAS_ACK_SEQ	3
283 #define RDS_MSG_ACK_REQUIRED	4
284 #define RDS_MSG_RETRANSMITTED	5
285 #define RDS_MSG_MAPPED		6
286 #define RDS_MSG_PAGEVEC		7
287 
288 struct rds_message {
289 	atomic_t		m_refcount;
290 	struct list_head	m_sock_item;
291 	struct list_head	m_conn_item;
292 	struct rds_incoming	m_inc;
293 	u64			m_ack_seq;
294 	__be32			m_daddr;
295 	unsigned long		m_flags;
296 
297 	/* Never access m_rs without holding m_rs_lock.
298 	 * Lock nesting is
299 	 *  rm->m_rs_lock
300 	 *   -> rs->rs_lock
301 	 */
302 	spinlock_t		m_rs_lock;
303 	wait_queue_head_t	m_flush_wait;
304 
305 	struct rds_sock		*m_rs;
306 
307 	/* cookie to send to remote, in rds header */
308 	rds_rdma_cookie_t	m_rdma_cookie;
309 
310 	unsigned int		m_used_sgs;
311 	unsigned int		m_total_sgs;
312 
313 	void			*m_final_op;
314 
315 	struct {
316 		struct rm_atomic_op {
317 			int			op_type;
318 			union {
319 				struct {
320 					uint64_t	compare;
321 					uint64_t	swap;
322 					uint64_t	compare_mask;
323 					uint64_t	swap_mask;
324 				} op_m_cswp;
325 				struct {
326 					uint64_t	add;
327 					uint64_t	nocarry_mask;
328 				} op_m_fadd;
329 			};
330 
331 			u32			op_rkey;
332 			u64			op_remote_addr;
333 			unsigned int		op_notify:1;
334 			unsigned int		op_recverr:1;
335 			unsigned int		op_mapped:1;
336 			unsigned int		op_silent:1;
337 			unsigned int		op_active:1;
338 			struct scatterlist	*op_sg;
339 			struct rds_notifier	*op_notifier;
340 
341 			struct rds_mr		*op_rdma_mr;
342 		} atomic;
343 		struct rm_rdma_op {
344 			u32			op_rkey;
345 			u64			op_remote_addr;
346 			unsigned int		op_write:1;
347 			unsigned int		op_fence:1;
348 			unsigned int		op_notify:1;
349 			unsigned int		op_recverr:1;
350 			unsigned int		op_mapped:1;
351 			unsigned int		op_silent:1;
352 			unsigned int		op_active:1;
353 			unsigned int		op_bytes;
354 			unsigned int		op_nents;
355 			unsigned int		op_count;
356 			struct scatterlist	*op_sg;
357 			struct rds_notifier	*op_notifier;
358 
359 			struct rds_mr		*op_rdma_mr;
360 		} rdma;
361 		struct rm_data_op {
362 			unsigned int		op_active:1;
363 			unsigned int		op_nents;
364 			unsigned int		op_count;
365 			struct scatterlist	*op_sg;
366 		} data;
367 	};
368 };
369 
370 /*
371  * The RDS notifier is used (optionally) to tell the application about
372  * completed RDMA operations. Rather than keeping the whole rds message
373  * around on the queue, we allocate a small notifier that is put on the
374  * socket's notifier_list. Notifications are delivered to the application
375  * through control messages.
376  */
377 struct rds_notifier {
378 	struct list_head	n_list;
379 	uint64_t		n_user_token;
380 	int			n_status;
381 };
382 
383 /**
384  * struct rds_transport -  transport specific behavioural hooks
385  *
386  * @xmit: .xmit is called by rds_send_xmit() to tell the transport to send
387  *        part of a message.  The caller serializes on the send_sem so this
388  *        doesn't need to be reentrant for a given conn.  The header must be
389  *        sent before the data payload.  .xmit must be prepared to send a
390  *        message with no data payload.  .xmit should return the number of
391  *        bytes that were sent down the connection, including header bytes.
392  *        Returning 0 tells the caller that it doesn't need to perform any
393  *        additional work now.  This is usually the case when the transport has
394  *        filled the sending queue for its connection and will handle
395  *        triggering the rds thread to continue the send when space becomes
396  *        available.  Returning -EAGAIN tells the caller to retry the send
397  *        immediately.  Returning -ENOMEM tells the caller to retry the send at
398  *        some point in the future.
399  *
400  * @conn_shutdown: conn_shutdown stops traffic on the given connection.  Once
401  *                 it returns the connection can not call rds_recv_incoming().
402  *                 This will only be called once after conn_connect returns
403  *                 non-zero success and will The caller serializes this with
404  *                 the send and connecting paths (xmit_* and conn_*).  The
405  *                 transport is responsible for other serialization, including
406  *                 rds_recv_incoming().  This is called in process context but
407  *                 should try hard not to block.
408  */
409 
410 #define RDS_TRANS_IB	0
411 #define RDS_TRANS_IWARP	1
412 #define RDS_TRANS_TCP	2
413 #define RDS_TRANS_COUNT	3
414 
415 struct rds_transport {
416 	char			t_name[TRANSNAMSIZ];
417 	struct list_head	t_item;
418 	struct module		*t_owner;
419 	unsigned int		t_prefer_loopback:1;
420 	unsigned int		t_type;
421 
422 	int (*laddr_check)(__be32 addr);
423 	int (*conn_alloc)(struct rds_connection *conn, gfp_t gfp);
424 	void (*conn_free)(void *data);
425 	int (*conn_connect)(struct rds_connection *conn);
426 	void (*conn_shutdown)(struct rds_connection *conn);
427 	void (*xmit_prepare)(struct rds_connection *conn);
428 	void (*xmit_complete)(struct rds_connection *conn);
429 	int (*xmit)(struct rds_connection *conn, struct rds_message *rm,
430 		    unsigned int hdr_off, unsigned int sg, unsigned int off);
431 	int (*xmit_rdma)(struct rds_connection *conn, struct rm_rdma_op *op);
432 	int (*xmit_atomic)(struct rds_connection *conn, struct rm_atomic_op *op);
433 	int (*recv)(struct rds_connection *conn);
434 	int (*inc_copy_to_user)(struct rds_incoming *inc, struct iov_iter *to);
435 	void (*inc_free)(struct rds_incoming *inc);
436 
437 	int (*cm_handle_connect)(struct rdma_cm_id *cm_id,
438 				 struct rdma_cm_event *event);
439 	int (*cm_initiate_connect)(struct rdma_cm_id *cm_id);
440 	void (*cm_connect_complete)(struct rds_connection *conn,
441 				    struct rdma_cm_event *event);
442 
443 	unsigned int (*stats_info_copy)(struct rds_info_iterator *iter,
444 					unsigned int avail);
445 	void (*exit)(void);
446 	void *(*get_mr)(struct scatterlist *sg, unsigned long nr_sg,
447 			struct rds_sock *rs, u32 *key_ret);
448 	void (*sync_mr)(void *trans_private, int direction);
449 	void (*free_mr)(void *trans_private, int invalidate);
450 	void (*flush_mrs)(void);
451 };
452 
453 struct rds_sock {
454 	struct sock		rs_sk;
455 
456 	u64			rs_user_addr;
457 	u64			rs_user_bytes;
458 
459 	/*
460 	 * bound_addr used for both incoming and outgoing, no INADDR_ANY
461 	 * support.
462 	 */
463 	struct hlist_node	rs_bound_node;
464 	__be32			rs_bound_addr;
465 	__be32			rs_conn_addr;
466 	__be16			rs_bound_port;
467 	__be16			rs_conn_port;
468 	struct rds_transport    *rs_transport;
469 
470 	/*
471 	 * rds_sendmsg caches the conn it used the last time around.
472 	 * This helps avoid costly lookups.
473 	 */
474 	struct rds_connection	*rs_conn;
475 
476 	/* flag indicating we were congested or not */
477 	int			rs_congested;
478 	/* seen congestion (ENOBUFS) when sending? */
479 	int			rs_seen_congestion;
480 
481 	/* rs_lock protects all these adjacent members before the newline */
482 	spinlock_t		rs_lock;
483 	struct list_head	rs_send_queue;
484 	u32			rs_snd_bytes;
485 	int			rs_rcv_bytes;
486 	struct list_head	rs_notify_queue;	/* currently used for failed RDMAs */
487 
488 	/* Congestion wake_up. If rs_cong_monitor is set, we use cong_mask
489 	 * to decide whether the application should be woken up.
490 	 * If not set, we use rs_cong_track to find out whether a cong map
491 	 * update arrived.
492 	 */
493 	uint64_t		rs_cong_mask;
494 	uint64_t		rs_cong_notify;
495 	struct list_head	rs_cong_list;
496 	unsigned long		rs_cong_track;
497 
498 	/*
499 	 * rs_recv_lock protects the receive queue, and is
500 	 * used to serialize with rds_release.
501 	 */
502 	rwlock_t		rs_recv_lock;
503 	struct list_head	rs_recv_queue;
504 
505 	/* just for stats reporting */
506 	struct list_head	rs_item;
507 
508 	/* these have their own lock */
509 	spinlock_t		rs_rdma_lock;
510 	struct rb_root		rs_rdma_keys;
511 
512 	/* Socket options - in case there will be more */
513 	unsigned char		rs_recverr,
514 				rs_cong_monitor;
515 };
516 
517 static inline struct rds_sock *rds_sk_to_rs(const struct sock *sk)
518 {
519 	return container_of(sk, struct rds_sock, rs_sk);
520 }
521 static inline struct sock *rds_rs_to_sk(struct rds_sock *rs)
522 {
523 	return &rs->rs_sk;
524 }
525 
526 /*
527  * The stack assigns sk_sndbuf and sk_rcvbuf to twice the specified value
528  * to account for overhead.  We don't account for overhead, we just apply
529  * the number of payload bytes to the specified value.
530  */
531 static inline int rds_sk_sndbuf(struct rds_sock *rs)
532 {
533 	return rds_rs_to_sk(rs)->sk_sndbuf / 2;
534 }
535 static inline int rds_sk_rcvbuf(struct rds_sock *rs)
536 {
537 	return rds_rs_to_sk(rs)->sk_rcvbuf / 2;
538 }
539 
540 struct rds_statistics {
541 	uint64_t	s_conn_reset;
542 	uint64_t	s_recv_drop_bad_checksum;
543 	uint64_t	s_recv_drop_old_seq;
544 	uint64_t	s_recv_drop_no_sock;
545 	uint64_t	s_recv_drop_dead_sock;
546 	uint64_t	s_recv_deliver_raced;
547 	uint64_t	s_recv_delivered;
548 	uint64_t	s_recv_queued;
549 	uint64_t	s_recv_immediate_retry;
550 	uint64_t	s_recv_delayed_retry;
551 	uint64_t	s_recv_ack_required;
552 	uint64_t	s_recv_rdma_bytes;
553 	uint64_t	s_recv_ping;
554 	uint64_t	s_send_queue_empty;
555 	uint64_t	s_send_queue_full;
556 	uint64_t	s_send_lock_contention;
557 	uint64_t	s_send_lock_queue_raced;
558 	uint64_t	s_send_immediate_retry;
559 	uint64_t	s_send_delayed_retry;
560 	uint64_t	s_send_drop_acked;
561 	uint64_t	s_send_ack_required;
562 	uint64_t	s_send_queued;
563 	uint64_t	s_send_rdma;
564 	uint64_t	s_send_rdma_bytes;
565 	uint64_t	s_send_pong;
566 	uint64_t	s_page_remainder_hit;
567 	uint64_t	s_page_remainder_miss;
568 	uint64_t	s_copy_to_user;
569 	uint64_t	s_copy_from_user;
570 	uint64_t	s_cong_update_queued;
571 	uint64_t	s_cong_update_received;
572 	uint64_t	s_cong_send_error;
573 	uint64_t	s_cong_send_blocked;
574 };
575 
576 /* af_rds.c */
577 char *rds_str_array(char **array, size_t elements, size_t index);
578 void rds_sock_addref(struct rds_sock *rs);
579 void rds_sock_put(struct rds_sock *rs);
580 void rds_wake_sk_sleep(struct rds_sock *rs);
581 static inline void __rds_wake_sk_sleep(struct sock *sk)
582 {
583 	wait_queue_head_t *waitq = sk_sleep(sk);
584 
585 	if (!sock_flag(sk, SOCK_DEAD) && waitq)
586 		wake_up(waitq);
587 }
588 extern wait_queue_head_t rds_poll_waitq;
589 
590 
591 /* bind.c */
592 int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
593 void rds_remove_bound(struct rds_sock *rs);
594 struct rds_sock *rds_find_bound(__be32 addr, __be16 port);
595 
596 /* cong.c */
597 int rds_cong_get_maps(struct rds_connection *conn);
598 void rds_cong_add_conn(struct rds_connection *conn);
599 void rds_cong_remove_conn(struct rds_connection *conn);
600 void rds_cong_set_bit(struct rds_cong_map *map, __be16 port);
601 void rds_cong_clear_bit(struct rds_cong_map *map, __be16 port);
602 int rds_cong_wait(struct rds_cong_map *map, __be16 port, int nonblock, struct rds_sock *rs);
603 void rds_cong_queue_updates(struct rds_cong_map *map);
604 void rds_cong_map_updated(struct rds_cong_map *map, uint64_t);
605 int rds_cong_updated_since(unsigned long *recent);
606 void rds_cong_add_socket(struct rds_sock *);
607 void rds_cong_remove_socket(struct rds_sock *);
608 void rds_cong_exit(void);
609 struct rds_message *rds_cong_update_alloc(struct rds_connection *conn);
610 
611 /* conn.c */
612 int rds_conn_init(void);
613 void rds_conn_exit(void);
614 struct rds_connection *rds_conn_create(__be32 laddr, __be32 faddr,
615 				       struct rds_transport *trans, gfp_t gfp);
616 struct rds_connection *rds_conn_create_outgoing(__be32 laddr, __be32 faddr,
617 			       struct rds_transport *trans, gfp_t gfp);
618 void rds_conn_shutdown(struct rds_connection *conn);
619 void rds_conn_destroy(struct rds_connection *conn);
620 void rds_conn_drop(struct rds_connection *conn);
621 void rds_conn_connect_if_down(struct rds_connection *conn);
622 void rds_for_each_conn_info(struct socket *sock, unsigned int len,
623 			  struct rds_info_iterator *iter,
624 			  struct rds_info_lengths *lens,
625 			  int (*visitor)(struct rds_connection *, void *),
626 			  size_t item_len);
627 __printf(2, 3)
628 void __rds_conn_error(struct rds_connection *conn, const char *, ...);
629 #define rds_conn_error(conn, fmt...) \
630 	__rds_conn_error(conn, KERN_WARNING "RDS: " fmt)
631 
632 static inline int
633 rds_conn_transition(struct rds_connection *conn, int old, int new)
634 {
635 	return atomic_cmpxchg(&conn->c_state, old, new) == old;
636 }
637 
638 static inline int
639 rds_conn_state(struct rds_connection *conn)
640 {
641 	return atomic_read(&conn->c_state);
642 }
643 
644 static inline int
645 rds_conn_up(struct rds_connection *conn)
646 {
647 	return atomic_read(&conn->c_state) == RDS_CONN_UP;
648 }
649 
650 static inline int
651 rds_conn_connecting(struct rds_connection *conn)
652 {
653 	return atomic_read(&conn->c_state) == RDS_CONN_CONNECTING;
654 }
655 
656 /* message.c */
657 struct rds_message *rds_message_alloc(unsigned int nents, gfp_t gfp);
658 struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents);
659 int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from);
660 struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len);
661 void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
662 				 __be16 dport, u64 seq);
663 int rds_message_add_extension(struct rds_header *hdr,
664 			      unsigned int type, const void *data, unsigned int len);
665 int rds_message_next_extension(struct rds_header *hdr,
666 			       unsigned int *pos, void *buf, unsigned int *buflen);
667 int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset);
668 int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
669 void rds_message_inc_free(struct rds_incoming *inc);
670 void rds_message_addref(struct rds_message *rm);
671 void rds_message_put(struct rds_message *rm);
672 void rds_message_wait(struct rds_message *rm);
673 void rds_message_unmapped(struct rds_message *rm);
674 
675 static inline void rds_message_make_checksum(struct rds_header *hdr)
676 {
677 	hdr->h_csum = 0;
678 	hdr->h_csum = ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2);
679 }
680 
681 static inline int rds_message_verify_checksum(const struct rds_header *hdr)
682 {
683 	return !hdr->h_csum || ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2) == 0;
684 }
685 
686 
687 /* page.c */
688 int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes,
689 			     gfp_t gfp);
690 int rds_page_copy_user(struct page *page, unsigned long offset,
691 		       void __user *ptr, unsigned long bytes,
692 		       int to_user);
693 #define rds_page_copy_to_user(page, offset, ptr, bytes) \
694 	rds_page_copy_user(page, offset, ptr, bytes, 1)
695 #define rds_page_copy_from_user(page, offset, ptr, bytes) \
696 	rds_page_copy_user(page, offset, ptr, bytes, 0)
697 void rds_page_exit(void);
698 
699 /* recv.c */
700 void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
701 		  __be32 saddr);
702 void rds_inc_put(struct rds_incoming *inc);
703 void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr,
704 		       struct rds_incoming *inc, gfp_t gfp);
705 int rds_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
706 		size_t size, int msg_flags);
707 void rds_clear_recv_queue(struct rds_sock *rs);
708 int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msg);
709 void rds_inc_info_copy(struct rds_incoming *inc,
710 		       struct rds_info_iterator *iter,
711 		       __be32 saddr, __be32 daddr, int flip);
712 
713 /* send.c */
714 int rds_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
715 		size_t payload_len);
716 void rds_send_reset(struct rds_connection *conn);
717 int rds_send_xmit(struct rds_connection *conn);
718 struct sockaddr_in;
719 void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest);
720 typedef int (*is_acked_func)(struct rds_message *rm, uint64_t ack);
721 void rds_send_drop_acked(struct rds_connection *conn, u64 ack,
722 			 is_acked_func is_acked);
723 int rds_send_pong(struct rds_connection *conn, __be16 dport);
724 struct rds_message *rds_send_get_message(struct rds_connection *,
725 					 struct rm_rdma_op *);
726 
727 /* rdma.c */
728 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force);
729 int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen);
730 int rds_get_mr_for_dest(struct rds_sock *rs, char __user *optval, int optlen);
731 int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen);
732 void rds_rdma_drop_keys(struct rds_sock *rs);
733 int rds_rdma_extra_size(struct rds_rdma_args *args);
734 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
735 			  struct cmsghdr *cmsg);
736 int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm,
737 			  struct cmsghdr *cmsg);
738 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
739 			  struct cmsghdr *cmsg);
740 int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm,
741 			  struct cmsghdr *cmsg);
742 void rds_rdma_free_op(struct rm_rdma_op *ro);
743 void rds_atomic_free_op(struct rm_atomic_op *ao);
744 void rds_rdma_send_complete(struct rds_message *rm, int wc_status);
745 void rds_atomic_send_complete(struct rds_message *rm, int wc_status);
746 int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm,
747 		    struct cmsghdr *cmsg);
748 
749 void __rds_put_mr_final(struct rds_mr *mr);
750 static inline void rds_mr_put(struct rds_mr *mr)
751 {
752 	if (atomic_dec_and_test(&mr->r_refcount))
753 		__rds_put_mr_final(mr);
754 }
755 
756 /* stats.c */
757 DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_statistics, rds_stats);
758 #define rds_stats_inc_which(which, member) do {		\
759 	per_cpu(which, get_cpu()).member++;		\
760 	put_cpu();					\
761 } while (0)
762 #define rds_stats_inc(member) rds_stats_inc_which(rds_stats, member)
763 #define rds_stats_add_which(which, member, count) do {		\
764 	per_cpu(which, get_cpu()).member += count;	\
765 	put_cpu();					\
766 } while (0)
767 #define rds_stats_add(member, count) rds_stats_add_which(rds_stats, member, count)
768 int rds_stats_init(void);
769 void rds_stats_exit(void);
770 void rds_stats_info_copy(struct rds_info_iterator *iter,
771 			 uint64_t *values, const char *const *names,
772 			 size_t nr);
773 
774 /* sysctl.c */
775 int rds_sysctl_init(void);
776 void rds_sysctl_exit(void);
777 extern unsigned long rds_sysctl_sndbuf_min;
778 extern unsigned long rds_sysctl_sndbuf_default;
779 extern unsigned long rds_sysctl_sndbuf_max;
780 extern unsigned long rds_sysctl_reconnect_min_jiffies;
781 extern unsigned long rds_sysctl_reconnect_max_jiffies;
782 extern unsigned int  rds_sysctl_max_unacked_packets;
783 extern unsigned int  rds_sysctl_max_unacked_bytes;
784 extern unsigned int  rds_sysctl_ping_enable;
785 extern unsigned long rds_sysctl_trace_flags;
786 extern unsigned int  rds_sysctl_trace_level;
787 
788 /* threads.c */
789 int rds_threads_init(void);
790 void rds_threads_exit(void);
791 extern struct workqueue_struct *rds_wq;
792 void rds_queue_reconnect(struct rds_connection *conn);
793 void rds_connect_worker(struct work_struct *);
794 void rds_shutdown_worker(struct work_struct *);
795 void rds_send_worker(struct work_struct *);
796 void rds_recv_worker(struct work_struct *);
797 void rds_connect_complete(struct rds_connection *conn);
798 
799 /* transport.c */
800 int rds_trans_register(struct rds_transport *trans);
801 void rds_trans_unregister(struct rds_transport *trans);
802 struct rds_transport *rds_trans_get_preferred(__be32 addr);
803 void rds_trans_put(struct rds_transport *trans);
804 unsigned int rds_trans_stats_info_copy(struct rds_info_iterator *iter,
805 				       unsigned int avail);
806 int rds_trans_init(void);
807 void rds_trans_exit(void);
808 
809 #endif
810