xref: /openbmc/linux/net/rds/ib.h (revision a17922de)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _RDS_IB_H
3 #define _RDS_IB_H
4 
5 #include <rdma/ib_verbs.h>
6 #include <rdma/rdma_cm.h>
7 #include <linux/interrupt.h>
8 #include <linux/pci.h>
9 #include <linux/slab.h>
10 #include "rds.h"
11 #include "rdma_transport.h"
12 
13 #define RDS_IB_MAX_SGE			8
14 #define RDS_IB_RECV_SGE 		2
15 
16 #define RDS_IB_DEFAULT_RECV_WR		1024
17 #define RDS_IB_DEFAULT_SEND_WR		256
18 #define RDS_IB_DEFAULT_FR_WR		256
19 #define RDS_IB_DEFAULT_FR_INV_WR	256
20 
21 #define RDS_IB_DEFAULT_RETRY_COUNT	1
22 
23 #define RDS_IB_SUPPORTED_PROTOCOLS	0x00000003	/* minor versions supported */
24 
25 #define RDS_IB_RECYCLE_BATCH_COUNT	32
26 
27 #define RDS_IB_WC_MAX			32
28 
29 extern struct rw_semaphore rds_ib_devices_lock;
30 extern struct list_head rds_ib_devices;
31 
32 /*
33  * IB posts RDS_FRAG_SIZE fragments of pages to the receive queues to
34  * try and minimize the amount of memory tied up both the device and
35  * socket receive queues.
36  */
37 struct rds_page_frag {
38 	struct list_head	f_item;
39 	struct list_head	f_cache_entry;
40 	struct scatterlist	f_sg;
41 };
42 
43 struct rds_ib_incoming {
44 	struct list_head	ii_frags;
45 	struct list_head	ii_cache_entry;
46 	struct rds_incoming	ii_inc;
47 };
48 
49 struct rds_ib_cache_head {
50 	struct list_head *first;
51 	unsigned long count;
52 };
53 
54 struct rds_ib_refill_cache {
55 	struct rds_ib_cache_head __percpu *percpu;
56 	struct list_head	 *xfer;
57 	struct list_head	 *ready;
58 };
59 
60 /* This is the common structure for the IB private data exchange in setting up
61  * an RDS connection.  The exchange is different for IPv4 and IPv6 connections.
62  * The reason is that the address size is different and the addresses
63  * exchanged are in the beginning of the structure.  Hence it is not possible
64  * for interoperability if same structure is used.
65  */
66 struct rds_ib_conn_priv_cmn {
67 	u8			ricpc_protocol_major;
68 	u8			ricpc_protocol_minor;
69 	__be16			ricpc_protocol_minor_mask;	/* bitmask */
70 	__be32			ricpc_reserved1;
71 	__be64			ricpc_ack_seq;
72 	__be32			ricpc_credit;	/* non-zero enables flow ctl */
73 };
74 
75 struct rds_ib_connect_private {
76 	/* Add new fields at the end, and don't permute existing fields. */
77 	__be32				dp_saddr;
78 	__be32				dp_daddr;
79 	struct rds_ib_conn_priv_cmn	dp_cmn;
80 };
81 
82 struct rds6_ib_connect_private {
83 	/* Add new fields at the end, and don't permute existing fields. */
84 	struct in6_addr			dp_saddr;
85 	struct in6_addr			dp_daddr;
86 	struct rds_ib_conn_priv_cmn	dp_cmn;
87 };
88 
89 #define dp_protocol_major	dp_cmn.ricpc_protocol_major
90 #define dp_protocol_minor	dp_cmn.ricpc_protocol_minor
91 #define dp_protocol_minor_mask	dp_cmn.ricpc_protocol_minor_mask
92 #define dp_ack_seq		dp_cmn.ricpc_ack_seq
93 #define dp_credit		dp_cmn.ricpc_credit
94 
95 union rds_ib_conn_priv {
96 	struct rds_ib_connect_private	ricp_v4;
97 	struct rds6_ib_connect_private	ricp_v6;
98 };
99 
100 struct rds_ib_send_work {
101 	void			*s_op;
102 	union {
103 		struct ib_send_wr	s_wr;
104 		struct ib_rdma_wr	s_rdma_wr;
105 		struct ib_atomic_wr	s_atomic_wr;
106 	};
107 	struct ib_sge		s_sge[RDS_IB_MAX_SGE];
108 	unsigned long		s_queued;
109 };
110 
111 struct rds_ib_recv_work {
112 	struct rds_ib_incoming 	*r_ibinc;
113 	struct rds_page_frag	*r_frag;
114 	struct ib_recv_wr	r_wr;
115 	struct ib_sge		r_sge[2];
116 };
117 
118 struct rds_ib_work_ring {
119 	u32		w_nr;
120 	u32		w_alloc_ptr;
121 	u32		w_alloc_ctr;
122 	u32		w_free_ptr;
123 	atomic_t	w_free_ctr;
124 };
125 
126 /* Rings are posted with all the allocations they'll need to queue the
127  * incoming message to the receiving socket so this can't fail.
128  * All fragments start with a header, so we can make sure we're not receiving
129  * garbage, and we can tell a small 8 byte fragment from an ACK frame.
130  */
131 struct rds_ib_ack_state {
132 	u64		ack_next;
133 	u64		ack_recv;
134 	unsigned int	ack_required:1;
135 	unsigned int	ack_next_valid:1;
136 	unsigned int	ack_recv_valid:1;
137 };
138 
139 
140 struct rds_ib_device;
141 
142 struct rds_ib_connection {
143 
144 	struct list_head	ib_node;
145 	struct rds_ib_device	*rds_ibdev;
146 	struct rds_connection	*conn;
147 
148 	/* alphabet soup, IBTA style */
149 	struct rdma_cm_id	*i_cm_id;
150 	struct ib_pd		*i_pd;
151 	struct ib_cq		*i_send_cq;
152 	struct ib_cq		*i_recv_cq;
153 	struct ib_wc		i_send_wc[RDS_IB_WC_MAX];
154 	struct ib_wc		i_recv_wc[RDS_IB_WC_MAX];
155 
156 	/* To control the number of wrs from fastreg */
157 	atomic_t		i_fastreg_wrs;
158 	atomic_t		i_fastunreg_wrs;
159 
160 	/* interrupt handling */
161 	struct tasklet_struct	i_send_tasklet;
162 	struct tasklet_struct	i_recv_tasklet;
163 
164 	/* tx */
165 	struct rds_ib_work_ring	i_send_ring;
166 	struct rm_data_op	*i_data_op;
167 	struct rds_header	*i_send_hdrs;
168 	dma_addr_t		i_send_hdrs_dma;
169 	struct rds_ib_send_work *i_sends;
170 	atomic_t		i_signaled_sends;
171 
172 	/* rx */
173 	struct mutex		i_recv_mutex;
174 	struct rds_ib_work_ring	i_recv_ring;
175 	struct rds_ib_incoming	*i_ibinc;
176 	u32			i_recv_data_rem;
177 	struct rds_header	*i_recv_hdrs;
178 	dma_addr_t		i_recv_hdrs_dma;
179 	struct rds_ib_recv_work *i_recvs;
180 	u64			i_ack_recv;	/* last ACK received */
181 	struct rds_ib_refill_cache i_cache_incs;
182 	struct rds_ib_refill_cache i_cache_frags;
183 	atomic_t		i_cache_allocs;
184 
185 	/* sending acks */
186 	unsigned long		i_ack_flags;
187 #ifdef KERNEL_HAS_ATOMIC64
188 	atomic64_t		i_ack_next;	/* next ACK to send */
189 #else
190 	spinlock_t		i_ack_lock;	/* protect i_ack_next */
191 	u64			i_ack_next;	/* next ACK to send */
192 #endif
193 	struct rds_header	*i_ack;
194 	struct ib_send_wr	i_ack_wr;
195 	struct ib_sge		i_ack_sge;
196 	dma_addr_t		i_ack_dma;
197 	unsigned long		i_ack_queued;
198 
199 	/* Flow control related information
200 	 *
201 	 * Our algorithm uses a pair variables that we need to access
202 	 * atomically - one for the send credits, and one posted
203 	 * recv credits we need to transfer to remote.
204 	 * Rather than protect them using a slow spinlock, we put both into
205 	 * a single atomic_t and update it using cmpxchg
206 	 */
207 	atomic_t		i_credits;
208 
209 	/* Protocol version specific information */
210 	unsigned int		i_flowctl:1;	/* enable/disable flow ctl */
211 
212 	/* Batched completions */
213 	unsigned int		i_unsignaled_wrs;
214 
215 	/* Endpoint role in connection */
216 	bool			i_active_side;
217 	atomic_t		i_cq_quiesce;
218 
219 	/* Send/Recv vectors */
220 	int			i_scq_vector;
221 	int			i_rcq_vector;
222 };
223 
224 /* This assumes that atomic_t is at least 32 bits */
225 #define IB_GET_SEND_CREDITS(v)	((v) & 0xffff)
226 #define IB_GET_POST_CREDITS(v)	((v) >> 16)
227 #define IB_SET_SEND_CREDITS(v)	((v) & 0xffff)
228 #define IB_SET_POST_CREDITS(v)	((v) << 16)
229 
230 struct rds_ib_ipaddr {
231 	struct list_head	list;
232 	__be32			ipaddr;
233 	struct rcu_head		rcu;
234 };
235 
236 enum {
237 	RDS_IB_MR_8K_POOL,
238 	RDS_IB_MR_1M_POOL,
239 };
240 
241 struct rds_ib_device {
242 	struct list_head	list;
243 	struct list_head	ipaddr_list;
244 	struct list_head	conn_list;
245 	struct ib_device	*dev;
246 	struct ib_pd		*pd;
247 	bool                    use_fastreg;
248 
249 	unsigned int		max_mrs;
250 	struct rds_ib_mr_pool	*mr_1m_pool;
251 	struct rds_ib_mr_pool   *mr_8k_pool;
252 	unsigned int		fmr_max_remaps;
253 	unsigned int		max_8k_mrs;
254 	unsigned int		max_1m_mrs;
255 	int			max_sge;
256 	unsigned int		max_wrs;
257 	unsigned int		max_initiator_depth;
258 	unsigned int		max_responder_resources;
259 	spinlock_t		spinlock;	/* protect the above */
260 	refcount_t		refcount;
261 	struct work_struct	free_work;
262 	int			*vector_load;
263 };
264 
265 #define ibdev_to_node(ibdev) dev_to_node((ibdev)->dev.parent)
266 #define rdsibdev_to_node(rdsibdev) ibdev_to_node(rdsibdev->dev)
267 
268 /* bits for i_ack_flags */
269 #define IB_ACK_IN_FLIGHT	0
270 #define IB_ACK_REQUESTED	1
271 
272 /* Magic WR_ID for ACKs */
273 #define RDS_IB_ACK_WR_ID	(~(u64) 0)
274 
275 struct rds_ib_statistics {
276 	uint64_t	s_ib_connect_raced;
277 	uint64_t	s_ib_listen_closed_stale;
278 	uint64_t	s_ib_evt_handler_call;
279 	uint64_t	s_ib_tasklet_call;
280 	uint64_t	s_ib_tx_cq_event;
281 	uint64_t	s_ib_tx_ring_full;
282 	uint64_t	s_ib_tx_throttle;
283 	uint64_t	s_ib_tx_sg_mapping_failure;
284 	uint64_t	s_ib_tx_stalled;
285 	uint64_t	s_ib_tx_credit_updates;
286 	uint64_t	s_ib_rx_cq_event;
287 	uint64_t	s_ib_rx_ring_empty;
288 	uint64_t	s_ib_rx_refill_from_cq;
289 	uint64_t	s_ib_rx_refill_from_thread;
290 	uint64_t	s_ib_rx_alloc_limit;
291 	uint64_t	s_ib_rx_total_frags;
292 	uint64_t	s_ib_rx_total_incs;
293 	uint64_t	s_ib_rx_credit_updates;
294 	uint64_t	s_ib_ack_sent;
295 	uint64_t	s_ib_ack_send_failure;
296 	uint64_t	s_ib_ack_send_delayed;
297 	uint64_t	s_ib_ack_send_piggybacked;
298 	uint64_t	s_ib_ack_received;
299 	uint64_t	s_ib_rdma_mr_8k_alloc;
300 	uint64_t	s_ib_rdma_mr_8k_free;
301 	uint64_t	s_ib_rdma_mr_8k_used;
302 	uint64_t	s_ib_rdma_mr_8k_pool_flush;
303 	uint64_t	s_ib_rdma_mr_8k_pool_wait;
304 	uint64_t	s_ib_rdma_mr_8k_pool_depleted;
305 	uint64_t	s_ib_rdma_mr_1m_alloc;
306 	uint64_t	s_ib_rdma_mr_1m_free;
307 	uint64_t	s_ib_rdma_mr_1m_used;
308 	uint64_t	s_ib_rdma_mr_1m_pool_flush;
309 	uint64_t	s_ib_rdma_mr_1m_pool_wait;
310 	uint64_t	s_ib_rdma_mr_1m_pool_depleted;
311 	uint64_t	s_ib_rdma_mr_8k_reused;
312 	uint64_t	s_ib_rdma_mr_1m_reused;
313 	uint64_t	s_ib_atomic_cswp;
314 	uint64_t	s_ib_atomic_fadd;
315 	uint64_t	s_ib_recv_added_to_cache;
316 	uint64_t	s_ib_recv_removed_from_cache;
317 };
318 
319 extern struct workqueue_struct *rds_ib_wq;
320 
321 /*
322  * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h
323  * doesn't define it.
324  */
325 static inline void rds_ib_dma_sync_sg_for_cpu(struct ib_device *dev,
326 					      struct scatterlist *sglist,
327 					      unsigned int sg_dma_len,
328 					      int direction)
329 {
330 	struct scatterlist *sg;
331 	unsigned int i;
332 
333 	for_each_sg(sglist, sg, sg_dma_len, i) {
334 		ib_dma_sync_single_for_cpu(dev,
335 				ib_sg_dma_address(dev, sg),
336 				ib_sg_dma_len(dev, sg),
337 				direction);
338 	}
339 }
340 #define ib_dma_sync_sg_for_cpu	rds_ib_dma_sync_sg_for_cpu
341 
342 static inline void rds_ib_dma_sync_sg_for_device(struct ib_device *dev,
343 						 struct scatterlist *sglist,
344 						 unsigned int sg_dma_len,
345 						 int direction)
346 {
347 	struct scatterlist *sg;
348 	unsigned int i;
349 
350 	for_each_sg(sglist, sg, sg_dma_len, i) {
351 		ib_dma_sync_single_for_device(dev,
352 				ib_sg_dma_address(dev, sg),
353 				ib_sg_dma_len(dev, sg),
354 				direction);
355 	}
356 }
357 #define ib_dma_sync_sg_for_device	rds_ib_dma_sync_sg_for_device
358 
359 
360 /* ib.c */
361 extern struct rds_transport rds_ib_transport;
362 struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device);
363 void rds_ib_dev_put(struct rds_ib_device *rds_ibdev);
364 extern struct ib_client rds_ib_client;
365 
366 extern unsigned int rds_ib_retry_count;
367 
368 extern spinlock_t ib_nodev_conns_lock;
369 extern struct list_head ib_nodev_conns;
370 
371 /* ib_cm.c */
372 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp);
373 void rds_ib_conn_free(void *arg);
374 int rds_ib_conn_path_connect(struct rds_conn_path *cp);
375 void rds_ib_conn_path_shutdown(struct rds_conn_path *cp);
376 void rds_ib_state_change(struct sock *sk);
377 int rds_ib_listen_init(void);
378 void rds_ib_listen_stop(void);
379 __printf(2, 3)
380 void __rds_ib_conn_error(struct rds_connection *conn, const char *, ...);
381 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
382 			     struct rdma_cm_event *event, bool isv6);
383 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id, bool isv6);
384 void rds_ib_cm_connect_complete(struct rds_connection *conn,
385 				struct rdma_cm_event *event);
386 
387 
388 #define rds_ib_conn_error(conn, fmt...) \
389 	__rds_ib_conn_error(conn, KERN_WARNING "RDS/IB: " fmt)
390 
391 /* ib_rdma.c */
392 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev,
393 			 struct in6_addr *ipaddr);
394 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
395 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
396 void rds_ib_destroy_nodev_conns(void);
397 void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
398 
399 /* ib_recv.c */
400 int rds_ib_recv_init(void);
401 void rds_ib_recv_exit(void);
402 int rds_ib_recv_path(struct rds_conn_path *conn);
403 int rds_ib_recv_alloc_caches(struct rds_ib_connection *ic);
404 void rds_ib_recv_free_caches(struct rds_ib_connection *ic);
405 void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp);
406 void rds_ib_inc_free(struct rds_incoming *inc);
407 int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
408 void rds_ib_recv_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc,
409 			     struct rds_ib_ack_state *state);
410 void rds_ib_recv_tasklet_fn(unsigned long data);
411 void rds_ib_recv_init_ring(struct rds_ib_connection *ic);
412 void rds_ib_recv_clear_ring(struct rds_ib_connection *ic);
413 void rds_ib_recv_init_ack(struct rds_ib_connection *ic);
414 void rds_ib_attempt_ack(struct rds_ib_connection *ic);
415 void rds_ib_ack_send_complete(struct rds_ib_connection *ic);
416 u64 rds_ib_piggyb_ack(struct rds_ib_connection *ic);
417 void rds_ib_set_ack(struct rds_ib_connection *ic, u64 seq, int ack_required);
418 
419 /* ib_ring.c */
420 void rds_ib_ring_init(struct rds_ib_work_ring *ring, u32 nr);
421 void rds_ib_ring_resize(struct rds_ib_work_ring *ring, u32 nr);
422 u32 rds_ib_ring_alloc(struct rds_ib_work_ring *ring, u32 val, u32 *pos);
423 void rds_ib_ring_free(struct rds_ib_work_ring *ring, u32 val);
424 void rds_ib_ring_unalloc(struct rds_ib_work_ring *ring, u32 val);
425 int rds_ib_ring_empty(struct rds_ib_work_ring *ring);
426 int rds_ib_ring_low(struct rds_ib_work_ring *ring);
427 u32 rds_ib_ring_oldest(struct rds_ib_work_ring *ring);
428 u32 rds_ib_ring_completed(struct rds_ib_work_ring *ring, u32 wr_id, u32 oldest);
429 extern wait_queue_head_t rds_ib_ring_empty_wait;
430 
431 /* ib_send.c */
432 void rds_ib_xmit_path_complete(struct rds_conn_path *cp);
433 int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
434 		unsigned int hdr_off, unsigned int sg, unsigned int off);
435 void rds_ib_send_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
436 void rds_ib_send_init_ring(struct rds_ib_connection *ic);
437 void rds_ib_send_clear_ring(struct rds_ib_connection *ic);
438 int rds_ib_xmit_rdma(struct rds_connection *conn, struct rm_rdma_op *op);
439 void rds_ib_send_add_credits(struct rds_connection *conn, unsigned int credits);
440 void rds_ib_advertise_credits(struct rds_connection *conn, unsigned int posted);
441 int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
442 			     u32 *adv_credits, int need_posted, int max_posted);
443 int rds_ib_xmit_atomic(struct rds_connection *conn, struct rm_atomic_op *op);
444 
445 /* ib_stats.c */
446 DECLARE_PER_CPU(struct rds_ib_statistics, rds_ib_stats);
447 #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
448 #define rds_ib_stats_add(member, count) \
449 		rds_stats_add_which(rds_ib_stats, member, count)
450 unsigned int rds_ib_stats_info_copy(struct rds_info_iterator *iter,
451 				    unsigned int avail);
452 
453 /* ib_sysctl.c */
454 int rds_ib_sysctl_init(void);
455 void rds_ib_sysctl_exit(void);
456 extern unsigned long rds_ib_sysctl_max_send_wr;
457 extern unsigned long rds_ib_sysctl_max_recv_wr;
458 extern unsigned long rds_ib_sysctl_max_unsig_wrs;
459 extern unsigned long rds_ib_sysctl_max_unsig_bytes;
460 extern unsigned long rds_ib_sysctl_max_recv_allocation;
461 extern unsigned int rds_ib_sysctl_flow_control;
462 
463 #endif
464