xref: /linux/net/rds/rds.h (revision d8f87aa5fa0a4276491fa8ef436cd22605a3f9ba)
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 #ifdef RDS_DEBUG
44 #define rdsdebug(fmt, args...) pr_debug("%s(): " fmt, __func__ , ##args)
45 #else
46 /* sigh, pr_debug() causes unused variable warnings */
47 static inline __printf(1, 2)
48 void rdsdebug(char *fmt, ...)
49 {
50 }
51 #endif
52 
53 #define RDS_FRAG_SHIFT	12
54 #define RDS_FRAG_SIZE	((unsigned int)(1 << RDS_FRAG_SHIFT))
55 
56 /* Used to limit both RDMA and non-RDMA RDS message to 1MB */
57 #define RDS_MAX_MSG_SIZE	((unsigned int)(1 << 20))
58 
59 #define RDS_CONG_MAP_BYTES	(65536 / 8)
60 #define RDS_CONG_MAP_PAGES	(PAGE_ALIGN(RDS_CONG_MAP_BYTES) / PAGE_SIZE)
61 #define RDS_CONG_MAP_PAGE_BITS	(PAGE_SIZE * 8)
62 
63 struct rds_cong_map {
64 	struct rb_node		m_rb_node;
65 	struct in6_addr		m_addr;
66 	wait_queue_head_t	m_waitq;
67 	struct list_head	m_conn_list;
68 	unsigned long		m_page_addrs[RDS_CONG_MAP_PAGES];
69 };
70 
71 
72 /*
73  * This is how we will track the connection state:
74  * A connection is always in one of the following
75  * states. Updates to the state are atomic and imply
76  * a memory barrier.
77  */
78 enum {
79 	RDS_CONN_DOWN = 0,
80 	RDS_CONN_CONNECTING,
81 	RDS_CONN_DISCONNECTING,
82 	RDS_CONN_UP,
83 	RDS_CONN_RESETTING,
84 	RDS_CONN_ERROR,
85 };
86 
87 /* Bits for c_flags */
88 #define RDS_LL_SEND_FULL	0
89 #define RDS_RECONNECT_PENDING	1
90 #define RDS_IN_XMIT		2
91 #define RDS_RECV_REFILL		3
92 #define	RDS_DESTROY_PENDING	4
93 
94 /* Max number of multipaths per RDS connection. Must be a power of 2 */
95 #define	RDS_MPATH_WORKERS	8
96 #define	RDS_MPATH_HASH(rs, n) (jhash_1word(ntohs((rs)->rs_bound_port), \
97 			       (rs)->rs_hash_initval) & ((n) - 1))
98 
99 #define IS_CANONICAL(laddr, faddr) (htonl(laddr) < htonl(faddr))
100 
101 /* Per mpath connection state */
102 struct rds_conn_path {
103 	struct rds_connection	*cp_conn;
104 	struct rds_message	*cp_xmit_rm;
105 	unsigned long		cp_xmit_sg;
106 	unsigned int		cp_xmit_hdr_off;
107 	unsigned int		cp_xmit_data_off;
108 	unsigned int		cp_xmit_atomic_sent;
109 	unsigned int		cp_xmit_rdma_sent;
110 	unsigned int		cp_xmit_data_sent;
111 
112 	spinlock_t		cp_lock;		/* protect msg queues */
113 	u64			cp_next_tx_seq;
114 	struct list_head	cp_send_queue;
115 	struct list_head	cp_retrans;
116 
117 	u64			cp_next_rx_seq;
118 
119 	void			*cp_transport_data;
120 
121 	struct workqueue_struct	*cp_wq;
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 	struct kref		r_kref;
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 	struct rds_sock		*r_sock; /* back pointer to the socket that owns us */
304 	struct rds_transport	*r_trans;
305 	void			*r_trans_private;
306 };
307 
308 static inline rds_rdma_cookie_t rds_rdma_make_cookie(u32 r_key, u32 offset)
309 {
310 	return r_key | (((u64) offset) << 32);
311 }
312 
313 static inline u32 rds_rdma_cookie_key(rds_rdma_cookie_t cookie)
314 {
315 	return cookie;
316 }
317 
318 static inline u32 rds_rdma_cookie_offset(rds_rdma_cookie_t cookie)
319 {
320 	return cookie >> 32;
321 }
322 
323 /* atomic operation types */
324 #define RDS_ATOMIC_TYPE_CSWP		0
325 #define RDS_ATOMIC_TYPE_FADD		1
326 
327 /*
328  * m_sock_item and m_conn_item are on lists that are serialized under
329  * conn->c_lock.  m_sock_item has additional meaning in that once it is empty
330  * the message will not be put back on the retransmit list after being sent.
331  * messages that are canceled while being sent rely on this.
332  *
333  * m_inc is used by loopback so that it can pass an incoming message straight
334  * back up into the rx path.  It embeds a wire header which is also used by
335  * the send path, which is kind of awkward.
336  *
337  * m_sock_item indicates the message's presence on a socket's send or receive
338  * queue.  m_rs will point to that socket.
339  *
340  * m_daddr is used by cancellation to prune messages to a given destination.
341  *
342  * The RDS_MSG_ON_SOCK and RDS_MSG_ON_CONN flags are used to avoid lock
343  * nesting.  As paths iterate over messages on a sock, or conn, they must
344  * also lock the conn, or sock, to remove the message from those lists too.
345  * Testing the flag to determine if the message is still on the lists lets
346  * us avoid testing the list_head directly.  That means each path can use
347  * the message's list_head to keep it on a local list while juggling locks
348  * without confusing the other path.
349  *
350  * m_ack_seq is an optional field set by transports who need a different
351  * sequence number range to invalidate.  They can use this in a callback
352  * that they pass to rds_send_drop_acked() to see if each message has been
353  * acked.  The HAS_ACK_SEQ flag can be used to detect messages which haven't
354  * had ack_seq set yet.
355  */
356 #define RDS_MSG_ON_SOCK		1
357 #define RDS_MSG_ON_CONN		2
358 #define RDS_MSG_HAS_ACK_SEQ	3
359 #define RDS_MSG_ACK_REQUIRED	4
360 #define RDS_MSG_RETRANSMITTED	5
361 #define RDS_MSG_MAPPED		6
362 #define RDS_MSG_PAGEVEC		7
363 #define RDS_MSG_FLUSH		8
364 
365 struct rds_znotifier {
366 	struct mmpin		z_mmp;
367 	u32			z_cookie;
368 };
369 
370 struct rds_msg_zcopy_info {
371 	struct list_head rs_zcookie_next;
372 	union {
373 		struct rds_znotifier znotif;
374 		struct rds_zcopy_cookies zcookies;
375 	};
376 };
377 
378 struct rds_msg_zcopy_queue {
379 	struct list_head zcookie_head;
380 	spinlock_t lock; /* protects zcookie_head queue */
381 };
382 
383 static inline void rds_message_zcopy_queue_init(struct rds_msg_zcopy_queue *q)
384 {
385 	spin_lock_init(&q->lock);
386 	INIT_LIST_HEAD(&q->zcookie_head);
387 }
388 
389 struct rds_iov_vector {
390 	struct rds_iovec *iov;
391 	int               len;
392 };
393 
394 struct rds_iov_vector_arr {
395 	struct rds_iov_vector *vec;
396 	int                    len;
397 	int                    indx;
398 	int                    incr;
399 };
400 
401 struct rds_message {
402 	refcount_t		m_refcount;
403 	struct list_head	m_sock_item;
404 	struct list_head	m_conn_item;
405 	struct rds_incoming	m_inc;
406 	u64			m_ack_seq;
407 	struct in6_addr		m_daddr;
408 	unsigned long		m_flags;
409 
410 	/* Never access m_rs without holding m_rs_lock.
411 	 * Lock nesting is
412 	 *  rm->m_rs_lock
413 	 *   -> rs->rs_lock
414 	 */
415 	spinlock_t		m_rs_lock;
416 	wait_queue_head_t	m_flush_wait;
417 
418 	struct rds_sock		*m_rs;
419 
420 	/* cookie to send to remote, in rds header */
421 	rds_rdma_cookie_t	m_rdma_cookie;
422 
423 	unsigned int		m_used_sgs;
424 	unsigned int		m_total_sgs;
425 
426 	void			*m_final_op;
427 
428 	struct {
429 		struct rm_atomic_op {
430 			int			op_type;
431 			union {
432 				struct {
433 					uint64_t	compare;
434 					uint64_t	swap;
435 					uint64_t	compare_mask;
436 					uint64_t	swap_mask;
437 				} op_m_cswp;
438 				struct {
439 					uint64_t	add;
440 					uint64_t	nocarry_mask;
441 				} op_m_fadd;
442 			};
443 
444 			u32			op_rkey;
445 			u64			op_remote_addr;
446 			unsigned int		op_notify:1;
447 			unsigned int		op_recverr:1;
448 			unsigned int		op_mapped:1;
449 			unsigned int		op_silent:1;
450 			unsigned int		op_active:1;
451 			struct scatterlist	*op_sg;
452 			struct rds_notifier	*op_notifier;
453 
454 			struct rds_mr		*op_rdma_mr;
455 		} atomic;
456 		struct rm_rdma_op {
457 			u32			op_rkey;
458 			u64			op_remote_addr;
459 			unsigned int		op_write:1;
460 			unsigned int		op_fence:1;
461 			unsigned int		op_notify:1;
462 			unsigned int		op_recverr:1;
463 			unsigned int		op_mapped:1;
464 			unsigned int		op_silent:1;
465 			unsigned int		op_active:1;
466 			unsigned int		op_bytes;
467 			unsigned int		op_nents;
468 			unsigned int		op_count;
469 			struct scatterlist	*op_sg;
470 			struct rds_notifier	*op_notifier;
471 
472 			struct rds_mr		*op_rdma_mr;
473 
474 			u64			op_odp_addr;
475 			struct rds_mr		*op_odp_mr;
476 		} rdma;
477 		struct rm_data_op {
478 			unsigned int		op_active:1;
479 			unsigned int		op_nents;
480 			unsigned int		op_count;
481 			unsigned int		op_dmasg;
482 			unsigned int		op_dmaoff;
483 			struct rds_znotifier	*op_mmp_znotifier;
484 			struct scatterlist	*op_sg;
485 		} data;
486 	};
487 
488 	struct rds_conn_path *m_conn_path;
489 };
490 
491 /*
492  * The RDS notifier is used (optionally) to tell the application about
493  * completed RDMA operations. Rather than keeping the whole rds message
494  * around on the queue, we allocate a small notifier that is put on the
495  * socket's notifier_list. Notifications are delivered to the application
496  * through control messages.
497  */
498 struct rds_notifier {
499 	struct list_head	n_list;
500 	uint64_t		n_user_token;
501 	int			n_status;
502 };
503 
504 /* Available as part of RDS core, so doesn't need to participate
505  * in get_preferred transport etc
506  */
507 #define	RDS_TRANS_LOOP	3
508 
509 /**
510  * struct rds_transport -  transport specific behavioural hooks
511  *
512  * @xmit: .xmit is called by rds_send_xmit() to tell the transport to send
513  *        part of a message.  The caller serializes on the send_sem so this
514  *        doesn't need to be reentrant for a given conn.  The header must be
515  *        sent before the data payload.  .xmit must be prepared to send a
516  *        message with no data payload.  .xmit should return the number of
517  *        bytes that were sent down the connection, including header bytes.
518  *        Returning 0 tells the caller that it doesn't need to perform any
519  *        additional work now.  This is usually the case when the transport has
520  *        filled the sending queue for its connection and will handle
521  *        triggering the rds thread to continue the send when space becomes
522  *        available.  Returning -EAGAIN tells the caller to retry the send
523  *        immediately.  Returning -ENOMEM tells the caller to retry the send at
524  *        some point in the future.
525  *
526  * @conn_shutdown: conn_shutdown stops traffic on the given connection.  Once
527  *                 it returns the connection can not call rds_recv_incoming().
528  *                 This will only be called once after conn_connect returns
529  *                 non-zero success and will The caller serializes this with
530  *                 the send and connecting paths (xmit_* and conn_*).  The
531  *                 transport is responsible for other serialization, including
532  *                 rds_recv_incoming().  This is called in process context but
533  *                 should try hard not to block.
534  */
535 
536 struct rds_transport {
537 	char			t_name[TRANSNAMSIZ];
538 	struct list_head	t_item;
539 	struct module		*t_owner;
540 	unsigned int		t_prefer_loopback:1,
541 				t_mp_capable:1;
542 	unsigned int		t_type;
543 
544 	int (*laddr_check)(struct net *net, const struct in6_addr *addr,
545 			   __u32 scope_id);
546 	int (*conn_alloc)(struct rds_connection *conn, gfp_t gfp);
547 	void (*conn_free)(void *data);
548 	int (*conn_path_connect)(struct rds_conn_path *cp);
549 	void (*conn_path_shutdown)(struct rds_conn_path *conn);
550 	void (*xmit_path_prepare)(struct rds_conn_path *cp);
551 	void (*xmit_path_complete)(struct rds_conn_path *cp);
552 	int (*xmit)(struct rds_connection *conn, struct rds_message *rm,
553 		    unsigned int hdr_off, unsigned int sg, unsigned int off);
554 	int (*xmit_rdma)(struct rds_connection *conn, struct rm_rdma_op *op);
555 	int (*xmit_atomic)(struct rds_connection *conn, struct rm_atomic_op *op);
556 	int (*recv_path)(struct rds_conn_path *cp);
557 	int (*inc_copy_to_user)(struct rds_incoming *inc, struct iov_iter *to);
558 	void (*inc_free)(struct rds_incoming *inc);
559 
560 	int (*cm_handle_connect)(struct rdma_cm_id *cm_id,
561 				 struct rdma_cm_event *event, bool isv6);
562 	int (*cm_initiate_connect)(struct rdma_cm_id *cm_id, bool isv6);
563 	void (*cm_connect_complete)(struct rds_connection *conn,
564 				    struct rdma_cm_event *event);
565 
566 	unsigned int (*stats_info_copy)(struct rds_info_iterator *iter,
567 					unsigned int avail);
568 	void (*exit)(void);
569 	void *(*get_mr)(struct scatterlist *sg, unsigned long nr_sg,
570 			struct rds_sock *rs, u32 *key_ret,
571 			struct rds_connection *conn,
572 			u64 start, u64 length, int need_odp);
573 	void (*sync_mr)(void *trans_private, int direction);
574 	void (*free_mr)(void *trans_private, int invalidate);
575 	void (*flush_mrs)(void);
576 	bool (*t_unloading)(struct rds_connection *conn);
577 	u8 (*get_tos_map)(u8 tos);
578 };
579 
580 /* Bind hash table key length.  It is the sum of the size of a struct
581  * in6_addr, a scope_id  and a port.
582  */
583 #define RDS_BOUND_KEY_LEN \
584 	(sizeof(struct in6_addr) + sizeof(__u32) + sizeof(__be16))
585 
586 struct rds_sock {
587 	struct sock		rs_sk;
588 
589 	u64			rs_user_addr;
590 	u64			rs_user_bytes;
591 
592 	/*
593 	 * bound_addr used for both incoming and outgoing, no INADDR_ANY
594 	 * support.
595 	 */
596 	struct rhash_head	rs_bound_node;
597 	u8			rs_bound_key[RDS_BOUND_KEY_LEN];
598 	struct sockaddr_in6	rs_bound_sin6;
599 #define rs_bound_addr		rs_bound_sin6.sin6_addr
600 #define rs_bound_addr_v4	rs_bound_sin6.sin6_addr.s6_addr32[3]
601 #define rs_bound_port		rs_bound_sin6.sin6_port
602 #define rs_bound_scope_id	rs_bound_sin6.sin6_scope_id
603 	struct in6_addr		rs_conn_addr;
604 #define rs_conn_addr_v4		rs_conn_addr.s6_addr32[3]
605 	__be16			rs_conn_port;
606 	struct rds_transport    *rs_transport;
607 
608 	/*
609 	 * rds_sendmsg caches the conn it used the last time around.
610 	 * This helps avoid costly lookups.
611 	 */
612 	struct rds_connection	*rs_conn;
613 
614 	/* flag indicating we were congested or not */
615 	int			rs_congested;
616 	/* seen congestion (ENOBUFS) when sending? */
617 	int			rs_seen_congestion;
618 
619 	/* rs_lock protects all these adjacent members before the newline */
620 	spinlock_t		rs_lock;
621 	struct list_head	rs_send_queue;
622 	u32			rs_snd_bytes;
623 	int			rs_rcv_bytes;
624 	struct list_head	rs_notify_queue;	/* currently used for failed RDMAs */
625 
626 	/* Congestion wake_up. If rs_cong_monitor is set, we use cong_mask
627 	 * to decide whether the application should be woken up.
628 	 * If not set, we use rs_cong_track to find out whether a cong map
629 	 * update arrived.
630 	 */
631 	uint64_t		rs_cong_mask;
632 	uint64_t		rs_cong_notify;
633 	struct list_head	rs_cong_list;
634 	unsigned long		rs_cong_track;
635 
636 	/*
637 	 * rs_recv_lock protects the receive queue, and is
638 	 * used to serialize with rds_release.
639 	 */
640 	rwlock_t		rs_recv_lock;
641 	struct list_head	rs_recv_queue;
642 
643 	/* just for stats reporting */
644 	struct list_head	rs_item;
645 
646 	/* these have their own lock */
647 	spinlock_t		rs_rdma_lock;
648 	struct rb_root		rs_rdma_keys;
649 
650 	/* Socket options - in case there will be more */
651 	unsigned char		rs_recverr,
652 				rs_cong_monitor;
653 	u32			rs_hash_initval;
654 
655 	/* Socket receive path trace points*/
656 	u8			rs_rx_traces;
657 	u8			rs_rx_trace[RDS_MSG_RX_DGRAM_TRACE_MAX];
658 	struct rds_msg_zcopy_queue rs_zcookie_queue;
659 	u8			rs_tos;
660 };
661 
662 static inline struct rds_sock *rds_sk_to_rs(const struct sock *sk)
663 {
664 	return container_of(sk, struct rds_sock, rs_sk);
665 }
666 static inline struct sock *rds_rs_to_sk(struct rds_sock *rs)
667 {
668 	return &rs->rs_sk;
669 }
670 
671 /*
672  * The stack assigns sk_sndbuf and sk_rcvbuf to twice the specified value
673  * to account for overhead.  We don't account for overhead, we just apply
674  * the number of payload bytes to the specified value.
675  */
676 static inline int rds_sk_sndbuf(struct rds_sock *rs)
677 {
678 	return rds_rs_to_sk(rs)->sk_sndbuf / 2;
679 }
680 static inline int rds_sk_rcvbuf(struct rds_sock *rs)
681 {
682 	return rds_rs_to_sk(rs)->sk_rcvbuf / 2;
683 }
684 
685 struct rds_statistics {
686 	uint64_t	s_conn_reset;
687 	uint64_t	s_recv_drop_bad_checksum;
688 	uint64_t	s_recv_drop_old_seq;
689 	uint64_t	s_recv_drop_no_sock;
690 	uint64_t	s_recv_drop_dead_sock;
691 	uint64_t	s_recv_deliver_raced;
692 	uint64_t	s_recv_delivered;
693 	uint64_t	s_recv_queued;
694 	uint64_t	s_recv_immediate_retry;
695 	uint64_t	s_recv_delayed_retry;
696 	uint64_t	s_recv_ack_required;
697 	uint64_t	s_recv_rdma_bytes;
698 	uint64_t	s_recv_ping;
699 	uint64_t	s_send_queue_empty;
700 	uint64_t	s_send_queue_full;
701 	uint64_t	s_send_lock_contention;
702 	uint64_t	s_send_lock_queue_raced;
703 	uint64_t	s_send_immediate_retry;
704 	uint64_t	s_send_delayed_retry;
705 	uint64_t	s_send_drop_acked;
706 	uint64_t	s_send_ack_required;
707 	uint64_t	s_send_queued;
708 	uint64_t	s_send_rdma;
709 	uint64_t	s_send_rdma_bytes;
710 	uint64_t	s_send_pong;
711 	uint64_t	s_page_remainder_hit;
712 	uint64_t	s_page_remainder_miss;
713 	uint64_t	s_copy_to_user;
714 	uint64_t	s_copy_from_user;
715 	uint64_t	s_cong_update_queued;
716 	uint64_t	s_cong_update_received;
717 	uint64_t	s_cong_send_error;
718 	uint64_t	s_cong_send_blocked;
719 	uint64_t	s_recv_bytes_added_to_socket;
720 	uint64_t	s_recv_bytes_removed_from_socket;
721 	uint64_t	s_send_stuck_rm;
722 };
723 
724 /* af_rds.c */
725 void rds_sock_addref(struct rds_sock *rs);
726 void rds_sock_put(struct rds_sock *rs);
727 void rds_wake_sk_sleep(struct rds_sock *rs);
728 static inline void __rds_wake_sk_sleep(struct sock *sk)
729 {
730 	wait_queue_head_t *waitq = sk_sleep(sk);
731 
732 	if (!sock_flag(sk, SOCK_DEAD) && waitq)
733 		wake_up(waitq);
734 }
735 extern wait_queue_head_t rds_poll_waitq;
736 
737 
738 /* bind.c */
739 int rds_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int addr_len);
740 void rds_remove_bound(struct rds_sock *rs);
741 struct rds_sock *rds_find_bound(const struct in6_addr *addr, __be16 port,
742 				__u32 scope_id);
743 int rds_bind_lock_init(void);
744 void rds_bind_lock_destroy(void);
745 
746 /* cong.c */
747 int rds_cong_get_maps(struct rds_connection *conn);
748 void rds_cong_add_conn(struct rds_connection *conn);
749 void rds_cong_remove_conn(struct rds_connection *conn);
750 void rds_cong_set_bit(struct rds_cong_map *map, __be16 port);
751 void rds_cong_clear_bit(struct rds_cong_map *map, __be16 port);
752 int rds_cong_wait(struct rds_cong_map *map, __be16 port, int nonblock, struct rds_sock *rs);
753 void rds_cong_queue_updates(struct rds_cong_map *map);
754 void rds_cong_map_updated(struct rds_cong_map *map, uint64_t);
755 int rds_cong_updated_since(unsigned long *recent);
756 void rds_cong_add_socket(struct rds_sock *);
757 void rds_cong_remove_socket(struct rds_sock *);
758 void rds_cong_exit(void);
759 struct rds_message *rds_cong_update_alloc(struct rds_connection *conn);
760 
761 /* connection.c */
762 extern u32 rds_gen_num;
763 int rds_conn_init(void);
764 void rds_conn_exit(void);
765 struct rds_connection *rds_conn_create(struct net *net,
766 				       const struct in6_addr *laddr,
767 				       const struct in6_addr *faddr,
768 				       struct rds_transport *trans,
769 				       u8 tos, gfp_t gfp,
770 				       int dev_if);
771 struct rds_connection *rds_conn_create_outgoing(struct net *net,
772 						const struct in6_addr *laddr,
773 						const struct in6_addr *faddr,
774 						struct rds_transport *trans,
775 						u8 tos, gfp_t gfp, int dev_if);
776 void rds_conn_shutdown(struct rds_conn_path *cpath);
777 void rds_conn_destroy(struct rds_connection *conn);
778 void rds_conn_drop(struct rds_connection *conn);
779 void rds_conn_path_drop(struct rds_conn_path *cpath, bool destroy);
780 void rds_conn_connect_if_down(struct rds_connection *conn);
781 void rds_conn_path_connect_if_down(struct rds_conn_path *cp);
782 void rds_check_all_paths(struct rds_connection *conn);
783 void rds_for_each_conn_info(struct socket *sock, unsigned int len,
784 			  struct rds_info_iterator *iter,
785 			  struct rds_info_lengths *lens,
786 			  int (*visitor)(struct rds_connection *, void *),
787 			  u64 *buffer,
788 			  size_t item_len);
789 
790 __printf(2, 3)
791 void __rds_conn_path_error(struct rds_conn_path *cp, const char *, ...);
792 #define rds_conn_path_error(cp, fmt...) \
793 	__rds_conn_path_error(cp, KERN_WARNING "RDS: " fmt)
794 
795 static inline int
796 rds_conn_path_transition(struct rds_conn_path *cp, int old, int new)
797 {
798 	return atomic_cmpxchg(&cp->cp_state, old, new) == old;
799 }
800 
801 static inline int
802 rds_conn_transition(struct rds_connection *conn, int old, int new)
803 {
804 	WARN_ON(conn->c_trans->t_mp_capable);
805 	return rds_conn_path_transition(&conn->c_path[0], old, new);
806 }
807 
808 static inline int
809 rds_conn_path_state(struct rds_conn_path *cp)
810 {
811 	return atomic_read(&cp->cp_state);
812 }
813 
814 static inline int
815 rds_conn_state(struct rds_connection *conn)
816 {
817 	WARN_ON(conn->c_trans->t_mp_capable);
818 	return rds_conn_path_state(&conn->c_path[0]);
819 }
820 
821 static inline int
822 rds_conn_path_up(struct rds_conn_path *cp)
823 {
824 	return atomic_read(&cp->cp_state) == RDS_CONN_UP;
825 }
826 
827 static inline int
828 rds_conn_path_down(struct rds_conn_path *cp)
829 {
830 	return atomic_read(&cp->cp_state) == RDS_CONN_DOWN;
831 }
832 
833 static inline int
834 rds_conn_up(struct rds_connection *conn)
835 {
836 	WARN_ON(conn->c_trans->t_mp_capable);
837 	return rds_conn_path_up(&conn->c_path[0]);
838 }
839 
840 static inline int
841 rds_conn_path_connecting(struct rds_conn_path *cp)
842 {
843 	return atomic_read(&cp->cp_state) == RDS_CONN_CONNECTING;
844 }
845 
846 static inline int
847 rds_conn_connecting(struct rds_connection *conn)
848 {
849 	WARN_ON(conn->c_trans->t_mp_capable);
850 	return rds_conn_path_connecting(&conn->c_path[0]);
851 }
852 
853 /* message.c */
854 struct rds_message *rds_message_alloc(unsigned int nents, gfp_t gfp);
855 struct scatterlist *rds_message_alloc_sgs(struct rds_message *rm, int nents);
856 int rds_message_copy_from_user(struct rds_message *rm, struct iov_iter *from,
857 			       bool zcopy);
858 struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned int total_len);
859 void rds_message_populate_header(struct rds_header *hdr, __be16 sport,
860 				 __be16 dport, u64 seq);
861 int rds_message_add_extension(struct rds_header *hdr,
862 			      unsigned int type, const void *data, unsigned int len);
863 int rds_message_next_extension(struct rds_header *hdr,
864 			       unsigned int *pos, void *buf, unsigned int *buflen);
865 int rds_message_add_rdma_dest_extension(struct rds_header *hdr, u32 r_key, u32 offset);
866 int rds_message_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
867 void rds_message_addref(struct rds_message *rm);
868 void rds_message_put(struct rds_message *rm);
869 void rds_message_wait(struct rds_message *rm);
870 void rds_message_unmapped(struct rds_message *rm);
871 void rds_notify_msg_zcopy_purge(struct rds_msg_zcopy_queue *info);
872 
873 static inline void rds_message_make_checksum(struct rds_header *hdr)
874 {
875 	hdr->h_csum = 0;
876 	hdr->h_csum = ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2);
877 }
878 
879 static inline int rds_message_verify_checksum(const struct rds_header *hdr)
880 {
881 	return !hdr->h_csum || ip_fast_csum((void *) hdr, sizeof(*hdr) >> 2) == 0;
882 }
883 
884 
885 /* page.c */
886 int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes,
887 			     gfp_t gfp);
888 void rds_page_exit(void);
889 
890 /* recv.c */
891 void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn,
892 		  struct in6_addr *saddr);
893 void rds_inc_path_init(struct rds_incoming *inc, struct rds_conn_path *conn,
894 		       struct in6_addr *saddr);
895 void rds_inc_put(struct rds_incoming *inc);
896 void rds_recv_incoming(struct rds_connection *conn, struct in6_addr *saddr,
897 		       struct in6_addr *daddr,
898 		       struct rds_incoming *inc, gfp_t gfp);
899 int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
900 		int msg_flags);
901 void rds_clear_recv_queue(struct rds_sock *rs);
902 int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msg);
903 void rds_inc_info_copy(struct rds_incoming *inc,
904 		       struct rds_info_iterator *iter,
905 		       __be32 saddr, __be32 daddr, int flip);
906 void rds6_inc_info_copy(struct rds_incoming *inc,
907 			struct rds_info_iterator *iter,
908 			struct in6_addr *saddr, struct in6_addr *daddr,
909 			int flip);
910 
911 /* send.c */
912 int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len);
913 void rds_send_path_reset(struct rds_conn_path *conn);
914 int rds_send_xmit(struct rds_conn_path *cp);
915 struct sockaddr_in;
916 void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in6 *dest);
917 typedef int (*is_acked_func)(struct rds_message *rm, uint64_t ack);
918 void rds_send_drop_acked(struct rds_connection *conn, u64 ack,
919 			 is_acked_func is_acked);
920 void rds_send_path_drop_acked(struct rds_conn_path *cp, u64 ack,
921 			      is_acked_func is_acked);
922 void rds_send_ping(struct rds_connection *conn, int cp_index);
923 int rds_send_pong(struct rds_conn_path *cp, __be16 dport);
924 
925 /* rdma.c */
926 void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force);
927 int rds_get_mr(struct rds_sock *rs, sockptr_t optval, int optlen);
928 int rds_get_mr_for_dest(struct rds_sock *rs, sockptr_t optval, int optlen);
929 int rds_free_mr(struct rds_sock *rs, sockptr_t optval, int optlen);
930 void rds_rdma_drop_keys(struct rds_sock *rs);
931 int rds_rdma_extra_size(struct rds_rdma_args *args,
932 			struct rds_iov_vector *iov);
933 int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm,
934 			  struct cmsghdr *cmsg);
935 int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
936 			  struct cmsghdr *cmsg,
937 			  struct rds_iov_vector *vec);
938 int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm,
939 			  struct cmsghdr *cmsg);
940 void rds_rdma_free_op(struct rm_rdma_op *ro);
941 void rds_atomic_free_op(struct rm_atomic_op *ao);
942 void rds_rdma_send_complete(struct rds_message *rm, int wc_status);
943 void rds_atomic_send_complete(struct rds_message *rm, int wc_status);
944 int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm,
945 		    struct cmsghdr *cmsg);
946 
947 void __rds_put_mr_final(struct kref *kref);
948 
949 static inline bool rds_destroy_pending(struct rds_connection *conn)
950 {
951 	return !check_net(rds_conn_net(conn)) ||
952 	       (conn->c_trans->t_unloading && conn->c_trans->t_unloading(conn));
953 }
954 
955 enum {
956 	ODP_NOT_NEEDED,
957 	ODP_ZEROBASED,
958 	ODP_VIRTUAL
959 };
960 
961 /* stats.c */
962 DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_statistics, rds_stats);
963 #define rds_stats_inc_which(which, member) do {		\
964 	per_cpu(which, get_cpu()).member++;		\
965 	put_cpu();					\
966 } while (0)
967 #define rds_stats_inc(member) rds_stats_inc_which(rds_stats, member)
968 #define rds_stats_add_which(which, member, count) do {		\
969 	per_cpu(which, get_cpu()).member += count;	\
970 	put_cpu();					\
971 } while (0)
972 #define rds_stats_add(member, count) rds_stats_add_which(rds_stats, member, count)
973 int rds_stats_init(void);
974 void rds_stats_exit(void);
975 void rds_stats_info_copy(struct rds_info_iterator *iter,
976 			 uint64_t *values, const char *const *names,
977 			 size_t nr);
978 
979 /* sysctl.c */
980 int rds_sysctl_init(void);
981 void rds_sysctl_exit(void);
982 extern unsigned long rds_sysctl_sndbuf_min;
983 extern unsigned long rds_sysctl_sndbuf_default;
984 extern unsigned long rds_sysctl_sndbuf_max;
985 extern unsigned long rds_sysctl_reconnect_min_jiffies;
986 extern unsigned long rds_sysctl_reconnect_max_jiffies;
987 extern unsigned int  rds_sysctl_max_unacked_packets;
988 extern unsigned int  rds_sysctl_max_unacked_bytes;
989 extern unsigned int  rds_sysctl_ping_enable;
990 extern unsigned long rds_sysctl_trace_flags;
991 extern unsigned int  rds_sysctl_trace_level;
992 
993 /* threads.c */
994 int rds_threads_init(void);
995 void rds_threads_exit(void);
996 extern struct workqueue_struct *rds_wq;
997 void rds_queue_reconnect(struct rds_conn_path *cp);
998 void rds_connect_worker(struct work_struct *);
999 void rds_shutdown_worker(struct work_struct *);
1000 void rds_send_worker(struct work_struct *);
1001 void rds_recv_worker(struct work_struct *);
1002 void rds_connect_path_complete(struct rds_conn_path *conn, int curr);
1003 void rds_connect_complete(struct rds_connection *conn);
1004 int rds_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2);
1005 
1006 /* transport.c */
1007 void rds_trans_register(struct rds_transport *trans);
1008 void rds_trans_unregister(struct rds_transport *trans);
1009 struct rds_transport *rds_trans_get_preferred(struct net *net,
1010 					      const struct in6_addr *addr,
1011 					      __u32 scope_id);
1012 void rds_trans_put(struct rds_transport *trans);
1013 unsigned int rds_trans_stats_info_copy(struct rds_info_iterator *iter,
1014 				       unsigned int avail);
1015 struct rds_transport *rds_trans_get(int t_type);
1016 
1017 #endif
1018