xref: /openbmc/linux/net/rds/ib.h (revision dc6a81c3)
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		512
19 
20 #define RDS_IB_DEFAULT_RETRY_COUNT	1
21 
22 #define RDS_IB_SUPPORTED_PROTOCOLS	0x00000003	/* minor versions supported */
23 
24 #define RDS_IB_RECYCLE_BATCH_COUNT	32
25 
26 #define RDS_IB_WC_MAX			32
27 
28 extern struct rw_semaphore rds_ib_devices_lock;
29 extern struct list_head rds_ib_devices;
30 
31 /*
32  * IB posts RDS_FRAG_SIZE fragments of pages to the receive queues to
33  * try and minimize the amount of memory tied up both the device and
34  * socket receive queues.
35  */
36 struct rds_page_frag {
37 	struct list_head	f_item;
38 	struct list_head	f_cache_entry;
39 	struct scatterlist	f_sg;
40 };
41 
42 struct rds_ib_incoming {
43 	struct list_head	ii_frags;
44 	struct list_head	ii_cache_entry;
45 	struct rds_incoming	ii_inc;
46 };
47 
48 struct rds_ib_cache_head {
49 	struct list_head *first;
50 	unsigned long count;
51 };
52 
53 struct rds_ib_refill_cache {
54 	struct rds_ib_cache_head __percpu *percpu;
55 	struct list_head	 *xfer;
56 	struct list_head	 *ready;
57 };
58 
59 /* This is the common structure for the IB private data exchange in setting up
60  * an RDS connection.  The exchange is different for IPv4 and IPv6 connections.
61  * The reason is that the address size is different and the addresses
62  * exchanged are in the beginning of the structure.  Hence it is not possible
63  * for interoperability if same structure is used.
64  */
65 struct rds_ib_conn_priv_cmn {
66 	u8			ricpc_protocol_major;
67 	u8			ricpc_protocol_minor;
68 	__be16			ricpc_protocol_minor_mask;	/* bitmask */
69 	u8			ricpc_dp_toss;
70 	u8			ripc_reserved1;
71 	__be16			ripc_reserved2;
72 	__be64			ricpc_ack_seq;
73 	__be32			ricpc_credit;	/* non-zero enables flow ctl */
74 };
75 
76 struct rds_ib_connect_private {
77 	/* Add new fields at the end, and don't permute existing fields. */
78 	__be32				dp_saddr;
79 	__be32				dp_daddr;
80 	struct rds_ib_conn_priv_cmn	dp_cmn;
81 };
82 
83 struct rds6_ib_connect_private {
84 	/* Add new fields at the end, and don't permute existing fields. */
85 	struct in6_addr			dp_saddr;
86 	struct in6_addr			dp_daddr;
87 	struct rds_ib_conn_priv_cmn	dp_cmn;
88 };
89 
90 #define dp_protocol_major	dp_cmn.ricpc_protocol_major
91 #define dp_protocol_minor	dp_cmn.ricpc_protocol_minor
92 #define dp_protocol_minor_mask	dp_cmn.ricpc_protocol_minor_mask
93 #define dp_ack_seq		dp_cmn.ricpc_ack_seq
94 #define dp_credit		dp_cmn.ricpc_credit
95 
96 union rds_ib_conn_priv {
97 	struct rds_ib_connect_private	ricp_v4;
98 	struct rds6_ib_connect_private	ricp_v6;
99 };
100 
101 struct rds_ib_send_work {
102 	void			*s_op;
103 	union {
104 		struct ib_send_wr	s_wr;
105 		struct ib_rdma_wr	s_rdma_wr;
106 		struct ib_atomic_wr	s_atomic_wr;
107 	};
108 	struct ib_sge		s_sge[RDS_IB_MAX_SGE];
109 	unsigned long		s_queued;
110 };
111 
112 struct rds_ib_recv_work {
113 	struct rds_ib_incoming 	*r_ibinc;
114 	struct rds_page_frag	*r_frag;
115 	struct ib_recv_wr	r_wr;
116 	struct ib_sge		r_sge[2];
117 };
118 
119 struct rds_ib_work_ring {
120 	u32		w_nr;
121 	u32		w_alloc_ptr;
122 	u32		w_alloc_ctr;
123 	u32		w_free_ptr;
124 	atomic_t	w_free_ctr;
125 };
126 
127 /* Rings are posted with all the allocations they'll need to queue the
128  * incoming message to the receiving socket so this can't fail.
129  * All fragments start with a header, so we can make sure we're not receiving
130  * garbage, and we can tell a small 8 byte fragment from an ACK frame.
131  */
132 struct rds_ib_ack_state {
133 	u64		ack_next;
134 	u64		ack_recv;
135 	unsigned int	ack_required:1;
136 	unsigned int	ack_next_valid:1;
137 	unsigned int	ack_recv_valid:1;
138 };
139 
140 
141 struct rds_ib_device;
142 
143 struct rds_ib_connection {
144 
145 	struct list_head	ib_node;
146 	struct rds_ib_device	*rds_ibdev;
147 	struct rds_connection	*conn;
148 
149 	/* alphabet soup, IBTA style */
150 	struct rdma_cm_id	*i_cm_id;
151 	struct ib_pd		*i_pd;
152 	struct ib_cq		*i_send_cq;
153 	struct ib_cq		*i_recv_cq;
154 	struct ib_wc		i_send_wc[RDS_IB_WC_MAX];
155 	struct ib_wc		i_recv_wc[RDS_IB_WC_MAX];
156 
157 	/* To control the number of wrs from fastreg */
158 	atomic_t		i_fastreg_wrs;
159 	atomic_t		i_fastreg_inuse_count;
160 
161 	/* interrupt handling */
162 	struct tasklet_struct	i_send_tasklet;
163 	struct tasklet_struct	i_recv_tasklet;
164 
165 	/* tx */
166 	struct rds_ib_work_ring	i_send_ring;
167 	struct rm_data_op	*i_data_op;
168 	struct rds_header	**i_send_hdrs;
169 	dma_addr_t		*i_send_hdrs_dma;
170 	struct rds_ib_send_work *i_sends;
171 	atomic_t		i_signaled_sends;
172 
173 	/* rx */
174 	struct mutex		i_recv_mutex;
175 	struct rds_ib_work_ring	i_recv_ring;
176 	struct rds_ib_incoming	*i_ibinc;
177 	u32			i_recv_data_rem;
178 	struct rds_header	**i_recv_hdrs;
179 	dma_addr_t		*i_recv_hdrs_dma;
180 	struct rds_ib_recv_work *i_recvs;
181 	u64			i_ack_recv;	/* last ACK received */
182 	struct rds_ib_refill_cache i_cache_incs;
183 	struct rds_ib_refill_cache i_cache_frags;
184 	atomic_t		i_cache_allocs;
185 
186 	/* sending acks */
187 	unsigned long		i_ack_flags;
188 #ifdef KERNEL_HAS_ATOMIC64
189 	atomic64_t		i_ack_next;	/* next ACK to send */
190 #else
191 	spinlock_t		i_ack_lock;	/* protect i_ack_next */
192 	u64			i_ack_next;	/* next ACK to send */
193 #endif
194 	struct rds_header	*i_ack;
195 	struct ib_send_wr	i_ack_wr;
196 	struct ib_sge		i_ack_sge;
197 	dma_addr_t		i_ack_dma;
198 	unsigned long		i_ack_queued;
199 
200 	/* Flow control related information
201 	 *
202 	 * Our algorithm uses a pair variables that we need to access
203 	 * atomically - one for the send credits, and one posted
204 	 * recv credits we need to transfer to remote.
205 	 * Rather than protect them using a slow spinlock, we put both into
206 	 * a single atomic_t and update it using cmpxchg
207 	 */
208 	atomic_t		i_credits;
209 
210 	/* Protocol version specific information */
211 	unsigned int		i_flowctl:1;	/* enable/disable flow ctl */
212 
213 	/* Batched completions */
214 	unsigned int		i_unsignaled_wrs;
215 
216 	/* Endpoint role in connection */
217 	bool			i_active_side;
218 	atomic_t		i_cq_quiesce;
219 
220 	/* Send/Recv vectors */
221 	int			i_scq_vector;
222 	int			i_rcq_vector;
223 	u8			i_sl;
224 };
225 
226 /* This assumes that atomic_t is at least 32 bits */
227 #define IB_GET_SEND_CREDITS(v)	((v) & 0xffff)
228 #define IB_GET_POST_CREDITS(v)	((v) >> 16)
229 #define IB_SET_SEND_CREDITS(v)	((v) & 0xffff)
230 #define IB_SET_POST_CREDITS(v)	((v) << 16)
231 
232 struct rds_ib_ipaddr {
233 	struct list_head	list;
234 	__be32			ipaddr;
235 	struct rcu_head		rcu;
236 };
237 
238 enum {
239 	RDS_IB_MR_8K_POOL,
240 	RDS_IB_MR_1M_POOL,
241 };
242 
243 struct rds_ib_device {
244 	struct list_head	list;
245 	struct list_head	ipaddr_list;
246 	struct list_head	conn_list;
247 	struct ib_device	*dev;
248 	struct ib_pd		*pd;
249 	struct dma_pool		*rid_hdrs_pool; /* RDS headers DMA pool */
250 	u8			use_fastreg:1;
251 	u8			odp_capable:1;
252 
253 	unsigned int		max_mrs;
254 	struct rds_ib_mr_pool	*mr_1m_pool;
255 	struct rds_ib_mr_pool   *mr_8k_pool;
256 	unsigned int		fmr_max_remaps;
257 	unsigned int		max_8k_mrs;
258 	unsigned int		max_1m_mrs;
259 	int			max_sge;
260 	unsigned int		max_wrs;
261 	unsigned int		max_initiator_depth;
262 	unsigned int		max_responder_resources;
263 	spinlock_t		spinlock;	/* protect the above */
264 	refcount_t		refcount;
265 	struct work_struct	free_work;
266 	int			*vector_load;
267 };
268 
269 #define ibdev_to_node(ibdev) dev_to_node((ibdev)->dev.parent)
270 #define rdsibdev_to_node(rdsibdev) ibdev_to_node(rdsibdev->dev)
271 
272 /* bits for i_ack_flags */
273 #define IB_ACK_IN_FLIGHT	0
274 #define IB_ACK_REQUESTED	1
275 
276 /* Magic WR_ID for ACKs */
277 #define RDS_IB_ACK_WR_ID	(~(u64) 0)
278 
279 struct rds_ib_statistics {
280 	uint64_t	s_ib_connect_raced;
281 	uint64_t	s_ib_listen_closed_stale;
282 	uint64_t	s_ib_evt_handler_call;
283 	uint64_t	s_ib_tasklet_call;
284 	uint64_t	s_ib_tx_cq_event;
285 	uint64_t	s_ib_tx_ring_full;
286 	uint64_t	s_ib_tx_throttle;
287 	uint64_t	s_ib_tx_sg_mapping_failure;
288 	uint64_t	s_ib_tx_stalled;
289 	uint64_t	s_ib_tx_credit_updates;
290 	uint64_t	s_ib_rx_cq_event;
291 	uint64_t	s_ib_rx_ring_empty;
292 	uint64_t	s_ib_rx_refill_from_cq;
293 	uint64_t	s_ib_rx_refill_from_thread;
294 	uint64_t	s_ib_rx_alloc_limit;
295 	uint64_t	s_ib_rx_total_frags;
296 	uint64_t	s_ib_rx_total_incs;
297 	uint64_t	s_ib_rx_credit_updates;
298 	uint64_t	s_ib_ack_sent;
299 	uint64_t	s_ib_ack_send_failure;
300 	uint64_t	s_ib_ack_send_delayed;
301 	uint64_t	s_ib_ack_send_piggybacked;
302 	uint64_t	s_ib_ack_received;
303 	uint64_t	s_ib_rdma_mr_8k_alloc;
304 	uint64_t	s_ib_rdma_mr_8k_free;
305 	uint64_t	s_ib_rdma_mr_8k_used;
306 	uint64_t	s_ib_rdma_mr_8k_pool_flush;
307 	uint64_t	s_ib_rdma_mr_8k_pool_wait;
308 	uint64_t	s_ib_rdma_mr_8k_pool_depleted;
309 	uint64_t	s_ib_rdma_mr_1m_alloc;
310 	uint64_t	s_ib_rdma_mr_1m_free;
311 	uint64_t	s_ib_rdma_mr_1m_used;
312 	uint64_t	s_ib_rdma_mr_1m_pool_flush;
313 	uint64_t	s_ib_rdma_mr_1m_pool_wait;
314 	uint64_t	s_ib_rdma_mr_1m_pool_depleted;
315 	uint64_t	s_ib_rdma_mr_8k_reused;
316 	uint64_t	s_ib_rdma_mr_1m_reused;
317 	uint64_t	s_ib_atomic_cswp;
318 	uint64_t	s_ib_atomic_fadd;
319 	uint64_t	s_ib_recv_added_to_cache;
320 	uint64_t	s_ib_recv_removed_from_cache;
321 };
322 
323 extern struct workqueue_struct *rds_ib_wq;
324 
325 /*
326  * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h
327  * doesn't define it.
328  */
329 static inline void rds_ib_dma_sync_sg_for_cpu(struct ib_device *dev,
330 					      struct scatterlist *sglist,
331 					      unsigned int sg_dma_len,
332 					      int direction)
333 {
334 	struct scatterlist *sg;
335 	unsigned int i;
336 
337 	for_each_sg(sglist, sg, sg_dma_len, i) {
338 		ib_dma_sync_single_for_cpu(dev, sg_dma_address(sg),
339 					   sg_dma_len(sg), direction);
340 	}
341 }
342 #define ib_dma_sync_sg_for_cpu	rds_ib_dma_sync_sg_for_cpu
343 
344 static inline void rds_ib_dma_sync_sg_for_device(struct ib_device *dev,
345 						 struct scatterlist *sglist,
346 						 unsigned int sg_dma_len,
347 						 int direction)
348 {
349 	struct scatterlist *sg;
350 	unsigned int i;
351 
352 	for_each_sg(sglist, sg, sg_dma_len, i) {
353 		ib_dma_sync_single_for_device(dev, sg_dma_address(sg),
354 					      sg_dma_len(sg), 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 struct rds_header **rds_dma_hdrs_alloc(struct ib_device *ibdev,
387 				       struct dma_pool *pool,
388 				       dma_addr_t **dma_addrs, u32 num_hdrs);
389 void rds_dma_hdrs_free(struct dma_pool *pool, struct rds_header **hdrs,
390 		       dma_addr_t *dma_addrs, u32 num_hdrs);
391 
392 #define rds_ib_conn_error(conn, fmt...) \
393 	__rds_ib_conn_error(conn, KERN_WARNING "RDS/IB: " fmt)
394 
395 /* ib_rdma.c */
396 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev,
397 			 struct in6_addr *ipaddr);
398 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
399 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
400 void rds_ib_destroy_nodev_conns(void);
401 void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
402 
403 /* ib_recv.c */
404 int rds_ib_recv_init(void);
405 void rds_ib_recv_exit(void);
406 int rds_ib_recv_path(struct rds_conn_path *conn);
407 int rds_ib_recv_alloc_caches(struct rds_ib_connection *ic, gfp_t gfp);
408 void rds_ib_recv_free_caches(struct rds_ib_connection *ic);
409 void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp);
410 void rds_ib_inc_free(struct rds_incoming *inc);
411 int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
412 void rds_ib_recv_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc,
413 			     struct rds_ib_ack_state *state);
414 void rds_ib_recv_tasklet_fn(unsigned long data);
415 void rds_ib_recv_init_ring(struct rds_ib_connection *ic);
416 void rds_ib_recv_clear_ring(struct rds_ib_connection *ic);
417 void rds_ib_recv_init_ack(struct rds_ib_connection *ic);
418 void rds_ib_attempt_ack(struct rds_ib_connection *ic);
419 void rds_ib_ack_send_complete(struct rds_ib_connection *ic);
420 u64 rds_ib_piggyb_ack(struct rds_ib_connection *ic);
421 void rds_ib_set_ack(struct rds_ib_connection *ic, u64 seq, int ack_required);
422 
423 /* ib_ring.c */
424 void rds_ib_ring_init(struct rds_ib_work_ring *ring, u32 nr);
425 void rds_ib_ring_resize(struct rds_ib_work_ring *ring, u32 nr);
426 u32 rds_ib_ring_alloc(struct rds_ib_work_ring *ring, u32 val, u32 *pos);
427 void rds_ib_ring_free(struct rds_ib_work_ring *ring, u32 val);
428 void rds_ib_ring_unalloc(struct rds_ib_work_ring *ring, u32 val);
429 int rds_ib_ring_empty(struct rds_ib_work_ring *ring);
430 int rds_ib_ring_low(struct rds_ib_work_ring *ring);
431 u32 rds_ib_ring_oldest(struct rds_ib_work_ring *ring);
432 u32 rds_ib_ring_completed(struct rds_ib_work_ring *ring, u32 wr_id, u32 oldest);
433 extern wait_queue_head_t rds_ib_ring_empty_wait;
434 
435 /* ib_send.c */
436 void rds_ib_xmit_path_complete(struct rds_conn_path *cp);
437 int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
438 		unsigned int hdr_off, unsigned int sg, unsigned int off);
439 void rds_ib_send_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
440 void rds_ib_send_init_ring(struct rds_ib_connection *ic);
441 void rds_ib_send_clear_ring(struct rds_ib_connection *ic);
442 int rds_ib_xmit_rdma(struct rds_connection *conn, struct rm_rdma_op *op);
443 void rds_ib_send_add_credits(struct rds_connection *conn, unsigned int credits);
444 void rds_ib_advertise_credits(struct rds_connection *conn, unsigned int posted);
445 int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
446 			     u32 *adv_credits, int need_posted, int max_posted);
447 int rds_ib_xmit_atomic(struct rds_connection *conn, struct rm_atomic_op *op);
448 
449 /* ib_stats.c */
450 DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_ib_statistics, rds_ib_stats);
451 #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
452 #define rds_ib_stats_add(member, count) \
453 		rds_stats_add_which(rds_ib_stats, member, count)
454 unsigned int rds_ib_stats_info_copy(struct rds_info_iterator *iter,
455 				    unsigned int avail);
456 
457 /* ib_sysctl.c */
458 int rds_ib_sysctl_init(void);
459 void rds_ib_sysctl_exit(void);
460 extern unsigned long rds_ib_sysctl_max_send_wr;
461 extern unsigned long rds_ib_sysctl_max_recv_wr;
462 extern unsigned long rds_ib_sysctl_max_unsig_wrs;
463 extern unsigned long rds_ib_sysctl_max_unsig_bytes;
464 extern unsigned long rds_ib_sysctl_max_recv_allocation;
465 extern unsigned int rds_ib_sysctl_flow_control;
466 
467 #endif
468