xref: /linux/net/rds/rds.h (revision 52338415)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _RDS_RDS_H
3 #define _RDS_RDS_H
4 
5 #include <net/sock.h>
6 #include <linux/scatterlist.h>
7 #include <linux/highmem.h>
8 #include <rdma/rdma_cm.h>
9 #include <linux/mutex.h>
10 #include <linux/rds.h>
11 #include <linux/rhashtable.h>
12 #include <linux/refcount.h>
13 #include <linux/in6.h>
14 
15 #include "info.h"
16 
17 /*
18  * RDS Network protocol version
19  */
20 #define RDS_PROTOCOL_3_0	0x0300
21 #define RDS_PROTOCOL_3_1	0x0301
22 #define RDS_PROTOCOL_4_0	0x0400
23 #define RDS_PROTOCOL_4_1	0x0401
24 #define RDS_PROTOCOL_VERSION	RDS_PROTOCOL_3_1
25 #define RDS_PROTOCOL_MAJOR(v)	((v) >> 8)
26 #define RDS_PROTOCOL_MINOR(v)	((v) & 255)
27 #define RDS_PROTOCOL(maj, min)	(((maj) << 8) | min)
28 #define RDS_PROTOCOL_COMPAT_VERSION	RDS_PROTOCOL_3_1
29 
30 /* The following ports, 16385, 18634, 18635, are registered with IANA as
31  * the ports to be used for RDS over TCP and UDP.  Currently, only RDS over
32  * TCP and RDS over IB/RDMA are implemented.  18634 is the historical value
33  * used for the RDMA_CM listener port.  RDS/TCP uses port 16385.  After
34  * IPv6 work, RDMA_CM also uses 16385 as the listener port.  18634 is kept
35  * to ensure compatibility with older RDS modules.  Those ports are defined
36  * in each transport's header file.
37  */
38 #define RDS_PORT	18634
39 
40 #ifdef ATOMIC64_INIT
41 #define KERNEL_HAS_ATOMIC64
42 #endif
43 
44 #ifdef RDS_DEBUG
45 #define rdsdebug(fmt, args...) pr_debug("%s(): " fmt, __func__ , ##args)
46 #else
47 /* sigh, pr_debug() causes unused variable warnings */
48 static inline __printf(1, 2)
49 void rdsdebug(char *fmt, ...)
50 {
51 }
52 #endif
53 
54 #define RDS_FRAG_SHIFT	12
55 #define RDS_FRAG_SIZE	((unsigned int)(1 << RDS_FRAG_SHIFT))
56 
57 /* Used to limit both RDMA and non-RDMA RDS message to 1MB */
58 #define RDS_MAX_MSG_SIZE	((unsigned int)(1 << 20))
59 
60 #define RDS_CONG_MAP_BYTES	(65536 / 8)
61 #define RDS_CONG_MAP_PAGES	(PAGE_ALIGN(RDS_CONG_MAP_BYTES) / PAGE_SIZE)
62 #define RDS_CONG_MAP_PAGE_BITS	(PAGE_SIZE * 8)
63 
64 struct rds_cong_map {
65 	struct rb_node		m_rb_node;
66 	struct in6_addr		m_addr;
67 	wait_queue_head_t	m_waitq;
68 	struct list_head	m_conn_list;
69 	unsigned long		m_page_addrs[RDS_CONG_MAP_PAGES];
70 };
71 
72 
73 /*
74  * This is how we will track the connection state:
75  * A connection is always in one of the following
76  * states. Updates to the state are atomic and imply
77  * a memory barrier.
78  */
79 enum {
80 	RDS_CONN_DOWN = 0,
81 	RDS_CONN_CONNECTING,
82 	RDS_CONN_DISCONNECTING,
83 	RDS_CONN_UP,
84 	RDS_CONN_RESETTING,
85 	RDS_CONN_ERROR,
86 };
87 
88 /* Bits for c_flags */
89 #define RDS_LL_SEND_FULL	0
90 #define RDS_RECONNECT_PENDING	1
91 #define RDS_IN_XMIT		2
92 #define RDS_RECV_REFILL		3
93 #define	RDS_DESTROY_PENDING	4
94 
95 /* Max number of multipaths per RDS connection. Must be a power of 2 */
96 #define	RDS_MPATH_WORKERS	8
97 #define	RDS_MPATH_HASH(rs, n) (jhash_1word((rs)->rs_bound_port, \
98 			       (rs)->rs_hash_initval) & ((n) - 1))
99 
100 #define IS_CANONICAL(laddr, faddr) (htonl(laddr) < htonl(faddr))
101 
102 /* Per mpath connection state */
103 struct rds_conn_path {
104 	struct rds_connection	*cp_conn;
105 	struct rds_message	*cp_xmit_rm;
106 	unsigned long		cp_xmit_sg;
107 	unsigned int		cp_xmit_hdr_off;
108 	unsigned int		cp_xmit_data_off;
109 	unsigned int		cp_xmit_atomic_sent;
110 	unsigned int		cp_xmit_rdma_sent;
111 	unsigned int		cp_xmit_data_sent;
112 
113 	spinlock_t		cp_lock;		/* protect msg queues */
114 	u64			cp_next_tx_seq;
115 	struct list_head	cp_send_queue;
116 	struct list_head	cp_retrans;
117 
118 	u64			cp_next_rx_seq;
119 
120 	void			*cp_transport_data;
121 
122 	atomic_t		cp_state;
123 	unsigned long		cp_send_gen;
124 	unsigned long		cp_flags;
125 	unsigned long		cp_reconnect_jiffies;
126 	struct delayed_work	cp_send_w;
127 	struct delayed_work	cp_recv_w;
128 	struct delayed_work	cp_conn_w;
129 	struct work_struct	cp_down_w;
130 	struct mutex		cp_cm_lock;	/* protect cp_state & cm */
131 	wait_queue_head_t	cp_waitq;
132 
133 	unsigned int		cp_unacked_packets;
134 	unsigned int		cp_unacked_bytes;
135 	unsigned int		cp_index;
136 };
137 
138 /* One rds_connection per RDS address pair */
139 struct rds_connection {
140 	struct hlist_node	c_hash_node;
141 	struct in6_addr		c_laddr;
142 	struct in6_addr		c_faddr;
143 	int			c_dev_if; /* ifindex used for this conn */
144 	int			c_bound_if; /* ifindex of c_laddr */
145 	unsigned int		c_loopback:1,
146 				c_isv6:1,
147 				c_ping_triggered:1,
148 				c_pad_to_32:29;
149 	int			c_npaths;
150 	struct rds_connection	*c_passive;
151 	struct rds_transport	*c_trans;
152 
153 	struct rds_cong_map	*c_lcong;
154 	struct rds_cong_map	*c_fcong;
155 
156 	/* Protocol version */
157 	unsigned int		c_proposed_version;
158 	unsigned int		c_version;
159 	possible_net_t		c_net;
160 
161 	/* TOS */
162 	u8			c_tos;
163 
164 	struct list_head	c_map_item;
165 	unsigned long		c_map_queued;
166 
167 	struct rds_conn_path	*c_path;
168 	wait_queue_head_t	c_hs_waitq; /* handshake waitq */
169 
170 	u32			c_my_gen_num;
171 	u32			c_peer_gen_num;
172 };
173 
174 static inline
175 struct net *rds_conn_net(struct rds_connection *conn)
176 {
177 	return read_pnet(&conn->c_net);
178 }
179 
180 static inline
181 void rds_conn_net_set(struct rds_connection *conn, struct net *net)
182 {
183 	write_pnet(&conn->c_net, net);
184 }
185 
186 #define RDS_FLAG_CONG_BITMAP	0x01
187 #define RDS_FLAG_ACK_REQUIRED	0x02
188 #define RDS_FLAG_RETRANSMITTED	0x04
189 #define RDS_MAX_ADV_CREDIT	255
190 
191 /* RDS_FLAG_PROBE_PORT is the reserved sport used for sending a ping
192  * probe to exchange control information before establishing a connection.
193  * Currently the control information that is exchanged is the number of
194  * supported paths. If the peer is a legacy (older kernel revision) peer,
195  * it would return a pong message without additional control information
196  * that would then alert the sender that the peer was an older rev.
197  */
198 #define RDS_FLAG_PROBE_PORT	1
199 #define	RDS_HS_PROBE(sport, dport) \
200 		((sport == RDS_FLAG_PROBE_PORT && dport == 0) || \
201 		 (sport == 0 && dport == RDS_FLAG_PROBE_PORT))
202 /*
203  * Maximum space available for extension headers.
204  */
205 #define RDS_HEADER_EXT_SPACE	16
206 
207 struct rds_header {
208 	__be64	h_sequence;
209 	__be64	h_ack;
210 	__be32	h_len;
211 	__be16	h_sport;
212 	__be16	h_dport;
213 	u8	h_flags;
214 	u8	h_credit;
215 	u8	h_padding[4];
216 	__sum16	h_csum;
217 
218 	u8	h_exthdr[RDS_HEADER_EXT_SPACE];
219 };
220 
221 /*
222  * Reserved - indicates end of extensions
223  */
224 #define RDS_EXTHDR_NONE		0
225 
226 /*
227  * This extension header is included in the very
228  * first message that is sent on a new connection,
229  * and identifies the protocol level. This will help
230  * rolling updates if a future change requires breaking
231  * the protocol.
232  * NB: This is no longer true for IB, where we do a version
233  * negotiation during the connection setup phase (protocol
234  * version information is included in the RDMA CM private data).
235  */
236 #define RDS_EXTHDR_VERSION	1
237 struct rds_ext_header_version {
238 	__be32			h_version;
239 };
240 
241 /*
242  * This extension header is included in the RDS message
243  * chasing an RDMA operation.
244  */
245 #define RDS_EXTHDR_RDMA		2
246 struct rds_ext_header_rdma {
247 	__be32			h_rdma_rkey;
248 };
249 
250 /*
251  * This extension header tells the peer about the
252  * destination <R_Key,offset> of the requested RDMA
253  * operation.
254  */
255 #define RDS_EXTHDR_RDMA_DEST	3
256 struct rds_ext_header_rdma_dest {
257 	__be32			h_rdma_rkey;
258 	__be32			h_rdma_offset;
259 };
260 
261 /* Extension header announcing number of paths.
262  * Implicit length = 2 bytes.
263  */
264 #define RDS_EXTHDR_NPATHS	5
265 #define RDS_EXTHDR_GEN_NUM	6
266 
267 #define __RDS_EXTHDR_MAX	16 /* for now */
268 #define RDS_RX_MAX_TRACES	(RDS_MSG_RX_DGRAM_TRACE_MAX + 1)
269 #define	RDS_MSG_RX_HDR		0
270 #define	RDS_MSG_RX_START	1
271 #define	RDS_MSG_RX_END		2
272 #define	RDS_MSG_RX_CMSG		3
273 
274 /* The following values are whitelisted for usercopy */
275 struct rds_inc_usercopy {
276 	rds_rdma_cookie_t	rdma_cookie;
277 	ktime_t			rx_tstamp;
278 };
279 
280 struct rds_incoming {
281 	refcount_t		i_refcount;
282 	struct list_head	i_item;
283 	struct rds_connection	*i_conn;
284 	struct rds_conn_path	*i_conn_path;
285 	struct rds_header	i_hdr;
286 	unsigned long		i_rx_jiffies;
287 	struct in6_addr		i_saddr;
288 
289 	struct rds_inc_usercopy i_usercopy;
290 	u64			i_rx_lat_trace[RDS_RX_MAX_TRACES];
291 };
292 
293 struct rds_mr {
294 	struct rb_node		r_rb_node;
295 	refcount_t		r_refcount;
296 	u32			r_key;
297 
298 	/* A copy of the creation flags */
299 	unsigned int		r_use_once:1;
300 	unsigned int		r_invalidate:1;
301 	unsigned int		r_write:1;
302 
303 	/* This is for RDS_MR_DEAD.
304 	 * It would be nice & consistent to make this part of the above
305 	 * bit field here, but we need to use test_and_set_bit.
306 	 */
307 	unsigned long		r_state;
308 	struct rds_sock		*r_sock; /* back pointer to the socket that owns us */
309 	struct rds_transport	*r_trans;
310 	void			*r_trans_private;
311 };
312 
313 /* Flags for mr->r_state */
314 #define RDS_MR_DEAD		0
315 
316 static inline rds_rdma_cookie_t rds_rdma_make_cookie(u32 r_key, u32 offset)
317 {
318 	return r_key | (((u64) offset) << 32);
319 }
320 
321 static inline u32 rds_rdma_cookie_key(rds_rdma_cookie_t cookie)
322 {
323 	return cookie;
324 }
325 
326 static inline u32 rds_rdma_cookie_offset(rds_rdma_cookie_t cookie)
327 {
328 	return cookie >> 32;
329 }
330 
331 /* atomic operation types */
332 #define RDS_ATOMIC_TYPE_CSWP		0
333 #define RDS_ATOMIC_TYPE_FADD		1
334 
335 /*
336  * m_sock_item and m_conn_item are on lists that are serialized under
337  * conn->c_lock.  m_sock_item has additional meaning in that once it is empty
338  * the message will not be put back on the retransmit list after being sent.
339  * messages that are canceled while being sent rely on this.
340  *
341  * m_inc is used by loopback so that it can pass an incoming message straight
342  * back up into the rx path.  It embeds a wire header which is also used by
343  * the send path, which is kind of awkward.
344  *
345  * m_sock_item indicates the message's presence on a socket's send or receive
346  * queue.  m_rs will point to that socket.
347  *
348  * m_daddr is used by cancellation to prune messages to a given destination.
349  *
350  * The RDS_MSG_ON_SOCK and RDS_MSG_ON_CONN flags are used to avoid lock
351  * nesting.  As paths iterate over messages on a sock, or conn, they must
352  * also lock the conn, or sock, to remove the message from those lists too.
353  * Testing the flag to determine if the message is still on the lists lets
354  * us avoid testing the list_head directly.  That means each path can use
355  * the message's list_head to keep it on a local list while juggling locks
356  * without confusing the other path.
357  *
358  * m_ack_seq is an optional field set by transports who need a different
359  * sequence number range to invalidate.  They can use this in a callback
360  * that they pass to rds_send_drop_acked() to see if each message has been
361  * acked.  The HAS_ACK_SEQ flag can be used to detect messages which haven't
362  * had ack_seq set yet.
363  */
364 #define RDS_MSG_ON_SOCK		1
365 #define RDS_MSG_ON_CONN		2
366 #define RDS_MSG_HAS_ACK_SEQ	3
367 #define RDS_MSG_ACK_REQUIRED	4
368 #define RDS_MSG_RETRANSMITTED	5
369 #define RDS_MSG_MAPPED		6
370 #define RDS_MSG_PAGEVEC		7
371 #define RDS_MSG_FLUSH		8
372 
373 struct rds_znotifier {
374 	struct mmpin		z_mmp;
375 	u32			z_cookie;
376 };
377 
378 struct rds_msg_zcopy_info {
379 	struct list_head rs_zcookie_next;
380 	union {
381 		struct rds_znotifier znotif;
382 		struct rds_zcopy_cookies zcookies;
383 	};
384 };
385 
386 struct rds_msg_zcopy_queue {
387 	struct list_head zcookie_head;
388 	spinlock_t lock; /* protects zcookie_head queue */
389 };
390 
391 static inline void rds_message_zcopy_queue_init(struct rds_msg_zcopy_queue *q)
392 {
393 	spin_lock_init(&q->lock);
394 	INIT_LIST_HEAD(&q->zcookie_head);
395 }
396 
397 struct rds_iov_vector {
398 	struct rds_iovec *iov;
399 	int               len;
400 };
401 
402 struct rds_iov_vector_arr {
403 	struct rds_iov_vector *vec;
404 	int                    len;
405 	int                    indx;
406 	int                    incr;
407 };
408 
409 struct rds_message {
410 	refcount_t		m_refcount;
411 	struct list_head	m_sock_item;
412 	struct list_head	m_conn_item;
413 	struct rds_incoming	m_inc;
414 	u64			m_ack_seq;
415 	struct in6_addr		m_daddr;
416 	unsigned long		m_flags;
417 
418 	/* Never access m_rs without holding m_rs_lock.
419 	 * Lock nesting is
420 	 *  rm->m_rs_lock
421 	 *   -> rs->rs_lock
422 	 */
423 	spinlock_t		m_rs_lock;
424 	wait_queue_head_t	m_flush_wait;
425 
426 	struct rds_sock		*m_rs;
427 
428 	/* cookie to send to remote, in rds header */
429 	rds_rdma_cookie_t	m_rdma_cookie;
430 
431 	unsigned int		m_used_sgs;
432 	unsigned int		m_total_sgs;
433 
434 	void			*m_final_op;
435 
436 	struct {
437 		struct rm_atomic_op {
438 			int			op_type;
439 			union {
440 				struct {
441 					uint64_t	compare;
442 					uint64_t	swap;
443 					uint64_t	compare_mask;
444 					uint64_t	swap_mask;
445 				} op_m_cswp;
446 				struct {
447 					uint64_t	add;
448 					uint64_t	nocarry_mask;
449 				} op_m_fadd;
450 			};
451 
452 			u32			op_rkey;
453 			u64			op_remote_addr;
454 			unsigned int		op_notify:1;
455 			unsigned int		op_recverr:1;
456 			unsigned int		op_mapped:1;
457 			unsigned int		op_silent:1;
458 			unsigned int		op_active:1;
459 			struct scatterlist	*op_sg;
460 			struct rds_notifier	*op_notifier;
461 
462 			struct rds_mr		*op_rdma_mr;
463 		} atomic;
464 		struct rm_rdma_op {
465 			u32			op_rkey;
466 			u64			op_remote_addr;
467 			unsigned int		op_write:1;
468 			unsigned int		op_fence:1;
469 			unsigned int		op_notify:1;
470 			unsigned int		op_recverr:1;
471 			unsigned int		op_mapped:1;
472 			unsigned int		op_silent:1;
473 			unsigned int		op_active:1;
474 			unsigned int		op_bytes;
475 			unsigned int		op_nents;
476 			unsigned int		op_count;
477 			struct scatterlist	*op_sg;
478 			struct rds_notifier	*op_notifier;
479 
480 			struct rds_mr		*op_rdma_mr;
481 		} rdma;
482 		struct rm_data_op {
483 			unsigned int		op_active:1;
484 			unsigned int		op_nents;
485 			unsigned int		op_count;
486 			unsigned int		op_dmasg;
487 			unsigned int		op_dmaoff;
488 			struct rds_znotifier	*op_mmp_znotifier;
489 			struct scatterlist	*op_sg;
490 		} data;
491 	};
492 
493 	struct rds_conn_path *m_conn_path;
494 };
495 
496 /*
497  * The RDS notifier is used (optionally) to tell the application about
498  * completed RDMA operations. Rather than keeping the whole rds message
499  * around on the queue, we allocate a small notifier that is put on the
500  * socket's notifier_list. Notifications are delivered to the application
501  * through control messages.
502  */
503 struct rds_notifier {
504 	struct list_head	n_list;
505 	uint64_t		n_user_token;
506 	int			n_status;
507 };
508 
509 /* Available as part of RDS core, so doesn't need to participate
510  * in get_preferred transport etc
511  */
512 #define	RDS_TRANS_LOOP	3
513 
514 /**
515  * struct rds_transport -  transport specific behavioural hooks
516  *
517  * @xmit: .xmit is called by rds_send_xmit() to tell the transport to send
518  *        part of a message.  The caller serializes on the send_sem so this
519  *        doesn't need to be reentrant for a given conn.  The header must be
520  *        sent before the data payload.  .xmit must be prepared to send a
521  *        message with no data payload.  .xmit should return the number of
522  *        bytes that were sent down the connection, including header bytes.
523  *        Returning 0 tells the caller that it doesn't need to perform any
524  *        additional work now.  This is usually the case when the transport has
525  *        filled the sending queue for its connection and will handle
526  *        triggering the rds thread to continue the send when space becomes
527  *        available.  Returning -EAGAIN tells the caller to retry the send
528  *        immediately.  Returning -ENOMEM tells the caller to retry the send at
529  *        some point in the future.
530  *
531  * @conn_shutdown: conn_shutdown stops traffic on the given connection.  Once
532  *                 it returns the connection can not call rds_recv_incoming().
533  *                 This will only be called once after conn_connect returns
534  *                 non-zero success and will The caller serializes this with
535  *                 the send and connecting paths (xmit_* and conn_*).  The
536  *                 transport is responsible for other serialization, including
537  *                 rds_recv_incoming().  This is called in process context but
538  *                 should try hard not to block.
539  */
540 
541 struct rds_transport {
542 	char			t_name[TRANSNAMSIZ];
543 	struct list_head	t_item;
544 	struct module		*t_owner;
545 	unsigned int		t_prefer_loopback:1,
546 				t_mp_capable:1;
547 	unsigned int		t_type;
548 
549 	int (*laddr_check)(struct net *net, const struct in6_addr *addr,
550 			   __u32 scope_id);
551 	int (*conn_alloc)(struct rds_connection *conn, gfp_t gfp);
552 	void (*conn_free)(void *data);
553 	int (*conn_path_connect)(struct rds_conn_path *cp);
554 	void (*conn_path_shutdown)(struct rds_conn_path *conn);
555 	void (*xmit_path_prepare)(struct rds_conn_path *cp);
556 	void (*xmit_path_complete)(struct rds_conn_path *cp);
557 	int (*xmit)(struct rds_connection *conn, struct rds_message *rm,
558 		    unsigned int hdr_off, unsigned int sg, unsigned int off);
559 	int (*xmit_rdma)(struct rds_connection *conn, struct rm_rdma_op *op);
560 	int (*xmit_atomic)(struct rds_connection *conn, struct rm_atomic_op *op);
561 	int (*recv_path)(struct rds_conn_path *cp);
562 	int (*inc_copy_to_user)(struct rds_incoming *inc, struct iov_iter *to);
563 	void (*inc_free)(struct rds_incoming *inc);
564 
565 	int (*cm_handle_connect)(struct rdma_cm_id *cm_id,
566 				 struct rdma_cm_event *event, bool isv6);
567 	int (*cm_initiate_connect)(struct rdma_cm_id *cm_id, bool isv6);
568 	void (*cm_connect_complete)(struct rds_connection *conn,
569 				    struct rdma_cm_event *event);
570 
571 	unsigned int (*stats_info_copy)(struct rds_info_iterator *iter,
572 					unsigned int avail);
573 	void (*exit)(void);
574 	void *(*get_mr)(struct scatterlist *sg, unsigned long nr_sg,
575 			struct rds_sock *rs, u32 *key_ret,
576 			struct rds_connection *conn);
577 	void (*sync_mr)(void *trans_private, int direction);
578 	void (*free_mr)(void *trans_private, int invalidate);
579 	void (*flush_mrs)(void);
580 	bool (*t_unloading)(struct rds_connection *conn);
581 	u8 (*get_tos_map)(u8 tos);
582 };
583 
584 /* Bind hash table key length.  It is the sum of the size of a struct
585  * in6_addr, a scope_id  and a port.
586  */
587 #define RDS_BOUND_KEY_LEN \
588 	(sizeof(struct in6_addr) + sizeof(__u32) + sizeof(__be16))
589 
590 struct rds_sock {
591 	struct sock		rs_sk;
592 
593 	u64			rs_user_addr;
594 	u64			rs_user_bytes;
595 
596 	/*
597 	 * bound_addr used for both incoming and outgoing, no INADDR_ANY
598 	 * support.
599 	 */
600 	struct rhash_head	rs_bound_node;
601 	u8			rs_bound_key[RDS_BOUND_KEY_LEN];
602 	struct sockaddr_in6	rs_bound_sin6;
603 #define rs_bound_addr		rs_bound_sin6.sin6_addr
604 #define rs_bound_addr_v4	rs_bound_sin6.sin6_addr.s6_addr32[3]
605 #define rs_bound_port		rs_bound_sin6.sin6_port
606 #define rs_bound_scope_id	rs_bound_sin6.sin6_scope_id
607 	struct in6_addr		rs_conn_addr;
608 #define rs_conn_addr_v4		rs_conn_addr.s6_addr32[3]
609 	__be16			rs_conn_port;
610 	struct rds_transport    *rs_transport;
611 
612 	/*
613 	 * rds_sendmsg caches the conn it used the last time around.
614 	 * This helps avoid costly lookups.
615 	 */
616 	struct rds_connection	*rs_conn;
617 
618 	/* flag indicating we were congested or not */
619 	int			rs_congested;
620 	/* seen congestion (ENOBUFS) when sending? */
621 	int			rs_seen_congestion;
622 
623 	/* rs_lock protects all these adjacent members before the newline */
624 	spinlock_t		rs_lock;
625 	struct list_head	rs_send_queue;
626 	u32			rs_snd_bytes;
627 	int			rs_rcv_bytes;
628 	struct list_head	rs_notify_queue;	/* currently used for failed RDMAs */
629 
630 	/* Congestion wake_up. If rs_cong_monitor is set, we use cong_mask
631 	 * to decide whether the application should be woken up.
632 	 * If not set, we use rs_cong_track to find out whether a cong map
633 	 * update arrived.
634 	 */
635 	uint64_t		rs_cong_mask;
636 	uint64_t		rs_cong_notify;
637 	struct list_head	rs_cong_list;
638 	unsigned long		rs_cong_track;
639 
640 	/*
641 	 * rs_recv_lock protects the receive queue, and is
642 	 * used to serialize with rds_release.
643 	 */
644 	rwlock_t		rs_recv_lock;
645 	struct list_head	rs_recv_queue;
646 
647 	/* just for stats reporting */
648 	struct list_head	rs_item;
649 
650 	/* these have their own lock */
651 	spinlock_t		rs_rdma_lock;
652 	struct rb_root		rs_rdma_keys;
653 
654 	/* Socket options - in case there will be more */
655 	unsigned char		rs_recverr,
656 				rs_cong_monitor;
657 	u32			rs_hash_initval;
658 
659 	/* Socket receive path trace points*/
660 	u8			rs_rx_traces;
661 	u8			rs_rx_trace[RDS_MSG_RX_DGRAM_TRACE_MAX];
662 	struct rds_msg_zcopy_queue rs_zcookie_queue;
663 	u8			rs_tos;
664 };
665 
666 static inline struct rds_sock *rds_sk_to_rs(const struct sock *sk)
667 {
668 	return container_of(sk, struct rds_sock, rs_sk);
669 }
670 static inline struct sock *rds_rs_to_sk(struct rds_sock *rs)
671 {
672 	return &rs->rs_sk;
673 }
674 
675 /*
676  * The stack assigns sk_sndbuf and sk_rcvbuf to twice the specified value
677  * to account for overhead.  We don't account for overhead, we just apply
678  * the number of payload bytes to the specified value.
679  */
680 static inline int rds_sk_sndbuf(struct rds_sock *rs)
681 {
682 	return rds_rs_to_sk(rs)->sk_sndbuf / 2;
683 }
684 static inline int rds_sk_rcvbuf(struct rds_sock *rs)
685 {
686 	return rds_rs_to_sk(rs)->sk_rcvbuf / 2;
687 }
688 
689 struct rds_statistics {
690 	uint64_t	s_conn_reset;
691 	uint64_t	s_recv_drop_bad_checksum;
692 	uint64_t	s_recv_drop_old_seq;
693 	uint64_t	s_recv_drop_no_sock;
694 	uint64_t	s_recv_drop_dead_sock;
695 	uint64_t	s_recv_deliver_raced;
696 	uint64_t	s_recv_delivered;
697 	uint64_t	s_recv_queued;
698 	uint64_t	s_recv_immediate_retry;
699 	uint64_t	s_recv_delayed_retry;
700 	uint64_t	s_recv_ack_required;
701 	uint64_t	s_recv_rdma_bytes;
702 	uint64_t	s_recv_ping;
703 	uint64_t	s_send_queue_empty;
704 	uint64_t	s_send_queue_full;
705 	uint64_t	s_send_lock_contention;
706 	uint64_t	s_send_lock_queue_raced;
707 	uint64_t	s_send_immediate_retry;
708 	uint64_t	s_send_delayed_retry;
709 	uint64_t	s_send_drop_acked;
710 	uint64_t	s_send_ack_required;
711 	uint64_t	s_send_queued;
712 	uint64_t	s_send_rdma;
713 	uint64_t	s_send_rdma_bytes;
714 	uint64_t	s_send_pong;
715 	uint64_t	s_page_remainder_hit;
716 	uint64_t	s_page_remainder_miss;
717 	uint64_t	s_copy_to_user;
718 	uint64_t	s_copy_from_user;
719 	uint64_t	s_cong_update_queued;
720 	uint64_t	s_cong_update_received;
721 	uint64_t	s_cong_send_error;
722 	uint64_t	s_cong_send_blocked;
723 	uint64_t	s_recv_bytes_added_to_socket;
724 	uint64_t	s_recv_bytes_removed_from_socket;
725 	uint64_t	s_send_stuck_rm;
726 };
727 
728 /* af_rds.c */
729 void rds_sock_addref(struct rds_sock *rs);
730 void rds_sock_put(struct rds_sock *rs);
731 void rds_wake_sk_sleep(struct rds_sock *rs);
732 static inline void __rds_wake_sk_sleep(struct sock *sk)
733 {
734 	wait_queue_head_t *waitq = sk_sleep(sk);
735 
736 	if (!sock_flag(sk, SOCK_DEAD) && waitq)
737 		wake_up(waitq);
738 }
739 extern wait_queue_head_t rds_poll_waitq;
740 
741 
742 /* bind.c */
743 int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len);
744 void rds_remove_bound(struct rds_sock *rs);
745 struct rds_sock *rds_find_bound(const struct in6_addr *addr, __be16 port,
746 				__u32 scope_id);
747 int rds_bind_lock_init(void);
748 void rds_bind_lock_destroy(void);
749 
750 /* cong.c */
751 int rds_cong_get_maps(struct rds_connection *conn);
752 void rds_cong_add_conn(struct rds_connection *conn);
753 void rds_cong_remove_conn(struct rds_connection *conn);
754 void rds_cong_set_bit(struct rds_cong_map *map, __be16 port);
755 void rds_cong_clear_bit(struct rds_cong_map *map, __be16 port);
756 int rds_cong_wait(struct rds_cong_map *map, __be16 port, int nonblock, struct rds_sock *rs);
757 void rds_cong_queue_updates(struct rds_cong_map *map);
758 void rds_cong_map_updated(struct rds_cong_map *map, uint64_t);
759 int rds_cong_updated_since(unsigned long *recent);
760 void rds_cong_add_socket(struct rds_sock *);
761 void rds_cong_remove_socket(struct rds_sock *);
762 void rds_cong_exit(void);
763 struct rds_message *rds_cong_update_alloc(struct rds_connection *conn);
764 
765 /* connection.c */
766 extern u32 rds_gen_num;
767 int rds_conn_init(void);
768 void rds_conn_exit(void);
769 struct rds_connection *rds_conn_create(struct net *net,
770 				       const struct in6_addr *laddr,
771 				       const struct in6_addr *faddr,
772 				       struct rds_transport *trans,
773 				       u8 tos, gfp_t gfp,
774 				       int dev_if);
775 struct rds_connection *rds_conn_create_outgoing(struct net *net,
776 						const struct in6_addr *laddr,
777 						const struct in6_addr *faddr,
778 						struct rds_transport *trans,
779 						u8 tos, gfp_t gfp, int dev_if);
780 void rds_conn_shutdown(struct rds_conn_path *cpath);
781 void rds_conn_destroy(struct rds_connection *conn);
782 void rds_conn_drop(struct rds_connection *conn);
783 void rds_conn_path_drop(struct rds_conn_path *cpath, bool destroy);
784 void rds_conn_connect_if_down(struct rds_connection *conn);
785 void rds_conn_path_connect_if_down(struct rds_conn_path *cp);
786 void rds_for_each_conn_info(struct socket *sock, unsigned int len,
787 			  struct rds_info_iterator *iter,
788 			  struct rds_info_lengths *lens,
789 			  int (*visitor)(struct rds_connection *, void *),
790 			  u64 *buffer,
791 			  size_t item_len);
792 
793 __printf(2, 3)
794 void __rds_conn_path_error(struct rds_conn_path *cp, const char *, ...);
795 #define rds_conn_path_error(cp, fmt...) \
796 	__rds_conn_path_error(cp, KERN_WARNING "RDS: " fmt)
797 
798 static inline int
799 rds_conn_path_transition(struct rds_conn_path *cp, int old, int new)
800 {
801 	return atomic_cmpxchg(&cp->cp_state, old, new) == old;
802 }
803 
804 static inline int
805 rds_conn_transition(struct rds_connection *conn, int old, int new)
806 {
807 	WARN_ON(conn->c_trans->t_mp_capable);
808 	return rds_conn_path_transition(&conn->c_path[0], old, new);
809 }
810 
811 static inline int
812 rds_conn_path_state(struct rds_conn_path *cp)
813 {
814 	return atomic_read(&cp->cp_state);
815 }
816 
817 static inline int
818 rds_conn_state(struct rds_connection *conn)
819 {
820 	WARN_ON(conn->c_trans->t_mp_capable);
821 	return rds_conn_path_state(&conn->c_path[0]);
822 }
823 
824 static inline int
825 rds_conn_path_up(struct rds_conn_path *cp)
826 {
827 	return atomic_read(&cp->cp_state) == RDS_CONN_UP;
828 }
829 
830 static inline int
831 rds_conn_up(struct rds_connection *conn)
832 {
833 	WARN_ON(conn->c_trans->t_mp_capable);
834 	return rds_conn_path_up(&conn->c_path[0]);
835 }
836 
837 static inline int
838 rds_conn_path_connecting(struct rds_conn_path *cp)
839 {
840 	return atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING;
841 }
842 
843 static inline int
844 rds_conn_connecting(struct rds_connection *conn)
845 {
846 	WARN_ON(conn->c_trans->t_mp_capable);
847 	return rds_conn_path_connecting(&conn->c_path[0]);
848 }
849 
850 /* message.c */
851 struct rds_message *rds_message_alloc(unsigned int nents, gfp_t gfp);
852 struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents,
853 					  int *ret);
854 int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from,
855 			       bool zcopy);
856 struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len);
857 void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
858 				 __be16 dport, u64 seq);
859 int rds_message_add_extension(struct rds_header *hdr,
860 			      unsigned int type, const void *data, unsigned int len);
861 int rds_message_next_extension(struct rds_header *hdr,
862 			       unsigned int *pos, void *buf, unsigned int *buflen);
863 int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset);
864 int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
865 void rds_message_inc_free(struct rds_incoming *inc);
866 void rds_message_addref(struct rds_message *rm);
867 void rds_message_put(struct rds_message *rm);
868 void rds_message_wait(struct rds_message *rm);
869 void rds_message_unmapped(struct rds_message *rm);
870 void rds_notify_msg_zcopy_purge(struct rds_msg_zcopy_queue *info);
871 
872 static inline void rds_message_make_checksum(struct rds_header *hdr)
873 {
874 	hdr->h_csum = 0;
875 	hdr->h_csum = ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2);
876 }
877 
878 static inline int rds_message_verify_checksum(const struct rds_header *hdr)
879 {
880 	return !hdr->h_csum || ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2) == 0;
881 }
882 
883 
884 /* page.c */
885 int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes,
886 			     gfp_t gfp);
887 void rds_page_exit(void);
888 
889 /* recv.c */
890 void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
891 		  struct in6_addr *saddr);
892 void rds_inc_path_init(struct rds_incoming *inc, struct rds_conn_path *conn,
893 		       struct in6_addr *saddr);
894 void rds_inc_put(struct rds_incoming *inc);
895 void rds_recv_incoming(struct rds_connection *conn, struct in6_addr *saddr,
896 		       struct in6_addr *daddr,
897 		       struct rds_incoming *inc, gfp_t gfp);
898 int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
899 		int msg_flags);
900 void rds_clear_recv_queue(struct rds_sock *rs);
901 int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msg);
902 void rds_inc_info_copy(struct rds_incoming *inc,
903 		       struct rds_info_iterator *iter,
904 		       __be32 saddr, __be32 daddr, int flip);
905 void rds6_inc_info_copy(struct rds_incoming *inc,
906 			struct rds_info_iterator *iter,
907 			struct in6_addr *saddr, struct in6_addr *daddr,
908 			int flip);
909 
910 /* send.c */
911 int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len);
912 void rds_send_path_reset(struct rds_conn_path *conn);
913 int rds_send_xmit(struct rds_conn_path *cp);
914 struct sockaddr_in;
915 void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in6 *dest);
916 typedef int (*is_acked_func)(struct rds_message *rm, uint64_t ack);
917 void rds_send_drop_acked(struct rds_connection *conn, u64 ack,
918 			 is_acked_func is_acked);
919 void rds_send_path_drop_acked(struct rds_conn_path *cp, u64 ack,
920 			      is_acked_func is_acked);
921 void rds_send_ping(struct rds_connection *conn, int cp_index);
922 int rds_send_pong(struct rds_conn_path *cp, __be16 dport);
923 
924 /* rdma.c */
925 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force);
926 int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen);
927 int rds_get_mr_for_dest(struct rds_sock *rs, char __user *optval, int optlen);
928 int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen);
929 void rds_rdma_drop_keys(struct rds_sock *rs);
930 int rds_rdma_extra_size(struct rds_rdma_args *args,
931 			struct rds_iov_vector *iov);
932 int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm,
933 			  struct cmsghdr *cmsg);
934 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
935 			  struct cmsghdr *cmsg,
936 			  struct rds_iov_vector *vec);
937 int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm,
938 			  struct cmsghdr *cmsg);
939 void rds_rdma_free_op(struct rm_rdma_op *ro);
940 void rds_atomic_free_op(struct rm_atomic_op *ao);
941 void rds_rdma_send_complete(struct rds_message *rm, int wc_status);
942 void rds_atomic_send_complete(struct rds_message *rm, int wc_status);
943 int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm,
944 		    struct cmsghdr *cmsg);
945 
946 void __rds_put_mr_final(struct rds_mr *mr);
947 static inline void rds_mr_put(struct rds_mr *mr)
948 {
949 	if (refcount_dec_and_test(&mr->r_refcount))
950 		__rds_put_mr_final(mr);
951 }
952 
953 static inline bool rds_destroy_pending(struct rds_connection *conn)
954 {
955 	return !check_net(rds_conn_net(conn)) ||
956 	       (conn->c_trans->t_unloading && conn->c_trans->t_unloading(conn));
957 }
958 
959 /* stats.c */
960 DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_statistics, rds_stats);
961 #define rds_stats_inc_which(which, member) do {		\
962 	per_cpu(which, get_cpu()).member++;		\
963 	put_cpu();					\
964 } while (0)
965 #define rds_stats_inc(member) rds_stats_inc_which(rds_stats, member)
966 #define rds_stats_add_which(which, member, count) do {		\
967 	per_cpu(which, get_cpu()).member += count;	\
968 	put_cpu();					\
969 } while (0)
970 #define rds_stats_add(member, count) rds_stats_add_which(rds_stats, member, count)
971 int rds_stats_init(void);
972 void rds_stats_exit(void);
973 void rds_stats_info_copy(struct rds_info_iterator *iter,
974 			 uint64_t *values, const char *const *names,
975 			 size_t nr);
976 
977 /* sysctl.c */
978 int rds_sysctl_init(void);
979 void rds_sysctl_exit(void);
980 extern unsigned long rds_sysctl_sndbuf_min;
981 extern unsigned long rds_sysctl_sndbuf_default;
982 extern unsigned long rds_sysctl_sndbuf_max;
983 extern unsigned long rds_sysctl_reconnect_min_jiffies;
984 extern unsigned long rds_sysctl_reconnect_max_jiffies;
985 extern unsigned int  rds_sysctl_max_unacked_packets;
986 extern unsigned int  rds_sysctl_max_unacked_bytes;
987 extern unsigned int  rds_sysctl_ping_enable;
988 extern unsigned long rds_sysctl_trace_flags;
989 extern unsigned int  rds_sysctl_trace_level;
990 
991 /* threads.c */
992 int rds_threads_init(void);
993 void rds_threads_exit(void);
994 extern struct workqueue_struct *rds_wq;
995 void rds_queue_reconnect(struct rds_conn_path *cp);
996 void rds_connect_worker(struct work_struct *);
997 void rds_shutdown_worker(struct work_struct *);
998 void rds_send_worker(struct work_struct *);
999 void rds_recv_worker(struct work_struct *);
1000 void rds_connect_path_complete(struct rds_conn_path *conn, int curr);
1001 void rds_connect_complete(struct rds_connection *conn);
1002 int rds_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2);
1003 
1004 /* transport.c */
1005 void rds_trans_register(struct rds_transport *trans);
1006 void rds_trans_unregister(struct rds_transport *trans);
1007 struct rds_transport *rds_trans_get_preferred(struct net *net,
1008 					      const struct in6_addr *addr,
1009 					      __u32 scope_id);
1010 void rds_trans_put(struct rds_transport *trans);
1011 unsigned int rds_trans_stats_info_copy(struct rds_info_iterator *iter,
1012 				       unsigned int avail);
1013 struct rds_transport *rds_trans_get(int t_type);
1014 int rds_trans_init(void);
1015 void rds_trans_exit(void);
1016 
1017 #endif
1018