xref: /openbmc/linux/net/rds/ib.h (revision faa16bc4)
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 struct rds_ib_connect_private {
61 	/* Add new fields at the end, and don't permute existing fields. */
62 	__be32			dp_saddr;
63 	__be32			dp_daddr;
64 	u8			dp_protocol_major;
65 	u8			dp_protocol_minor;
66 	__be16			dp_protocol_minor_mask; /* bitmask */
67 	__be32			dp_reserved1;
68 	__be64			dp_ack_seq;
69 	__be32			dp_credit;		/* non-zero enables flow ctl */
70 };
71 
72 struct rds_ib_send_work {
73 	void			*s_op;
74 	union {
75 		struct ib_send_wr	s_wr;
76 		struct ib_rdma_wr	s_rdma_wr;
77 		struct ib_atomic_wr	s_atomic_wr;
78 	};
79 	struct ib_sge		s_sge[RDS_IB_MAX_SGE];
80 	unsigned long		s_queued;
81 };
82 
83 struct rds_ib_recv_work {
84 	struct rds_ib_incoming 	*r_ibinc;
85 	struct rds_page_frag	*r_frag;
86 	struct ib_recv_wr	r_wr;
87 	struct ib_sge		r_sge[2];
88 };
89 
90 struct rds_ib_work_ring {
91 	u32		w_nr;
92 	u32		w_alloc_ptr;
93 	u32		w_alloc_ctr;
94 	u32		w_free_ptr;
95 	atomic_t	w_free_ctr;
96 };
97 
98 /* Rings are posted with all the allocations they'll need to queue the
99  * incoming message to the receiving socket so this can't fail.
100  * All fragments start with a header, so we can make sure we're not receiving
101  * garbage, and we can tell a small 8 byte fragment from an ACK frame.
102  */
103 struct rds_ib_ack_state {
104 	u64		ack_next;
105 	u64		ack_recv;
106 	unsigned int	ack_required:1;
107 	unsigned int	ack_next_valid:1;
108 	unsigned int	ack_recv_valid:1;
109 };
110 
111 
112 struct rds_ib_device;
113 
114 struct rds_ib_connection {
115 
116 	struct list_head	ib_node;
117 	struct rds_ib_device	*rds_ibdev;
118 	struct rds_connection	*conn;
119 
120 	/* alphabet soup, IBTA style */
121 	struct rdma_cm_id	*i_cm_id;
122 	struct ib_pd		*i_pd;
123 	struct ib_cq		*i_send_cq;
124 	struct ib_cq		*i_recv_cq;
125 	struct ib_wc		i_send_wc[RDS_IB_WC_MAX];
126 	struct ib_wc		i_recv_wc[RDS_IB_WC_MAX];
127 
128 	/* To control the number of wrs from fastreg */
129 	atomic_t		i_fastreg_wrs;
130 	atomic_t		i_fastunreg_wrs;
131 
132 	/* interrupt handling */
133 	struct tasklet_struct	i_send_tasklet;
134 	struct tasklet_struct	i_recv_tasklet;
135 
136 	/* tx */
137 	struct rds_ib_work_ring	i_send_ring;
138 	struct rm_data_op	*i_data_op;
139 	struct rds_header	*i_send_hdrs;
140 	dma_addr_t		i_send_hdrs_dma;
141 	struct rds_ib_send_work *i_sends;
142 	atomic_t		i_signaled_sends;
143 
144 	/* rx */
145 	struct mutex		i_recv_mutex;
146 	struct rds_ib_work_ring	i_recv_ring;
147 	struct rds_ib_incoming	*i_ibinc;
148 	u32			i_recv_data_rem;
149 	struct rds_header	*i_recv_hdrs;
150 	dma_addr_t		i_recv_hdrs_dma;
151 	struct rds_ib_recv_work *i_recvs;
152 	u64			i_ack_recv;	/* last ACK received */
153 	struct rds_ib_refill_cache i_cache_incs;
154 	struct rds_ib_refill_cache i_cache_frags;
155 	atomic_t		i_cache_allocs;
156 
157 	/* sending acks */
158 	unsigned long		i_ack_flags;
159 #ifdef KERNEL_HAS_ATOMIC64
160 	atomic64_t		i_ack_next;	/* next ACK to send */
161 #else
162 	spinlock_t		i_ack_lock;	/* protect i_ack_next */
163 	u64			i_ack_next;	/* next ACK to send */
164 #endif
165 	struct rds_header	*i_ack;
166 	struct ib_send_wr	i_ack_wr;
167 	struct ib_sge		i_ack_sge;
168 	dma_addr_t		i_ack_dma;
169 	unsigned long		i_ack_queued;
170 
171 	/* Flow control related information
172 	 *
173 	 * Our algorithm uses a pair variables that we need to access
174 	 * atomically - one for the send credits, and one posted
175 	 * recv credits we need to transfer to remote.
176 	 * Rather than protect them using a slow spinlock, we put both into
177 	 * a single atomic_t and update it using cmpxchg
178 	 */
179 	atomic_t		i_credits;
180 
181 	/* Protocol version specific information */
182 	unsigned int		i_flowctl:1;	/* enable/disable flow ctl */
183 
184 	/* Batched completions */
185 	unsigned int		i_unsignaled_wrs;
186 
187 	/* Endpoint role in connection */
188 	bool			i_active_side;
189 	atomic_t		i_cq_quiesce;
190 
191 	/* Send/Recv vectors */
192 	int			i_scq_vector;
193 	int			i_rcq_vector;
194 };
195 
196 /* This assumes that atomic_t is at least 32 bits */
197 #define IB_GET_SEND_CREDITS(v)	((v) & 0xffff)
198 #define IB_GET_POST_CREDITS(v)	((v) >> 16)
199 #define IB_SET_SEND_CREDITS(v)	((v) & 0xffff)
200 #define IB_SET_POST_CREDITS(v)	((v) << 16)
201 
202 struct rds_ib_ipaddr {
203 	struct list_head	list;
204 	__be32			ipaddr;
205 	struct rcu_head		rcu;
206 };
207 
208 enum {
209 	RDS_IB_MR_8K_POOL,
210 	RDS_IB_MR_1M_POOL,
211 };
212 
213 struct rds_ib_device {
214 	struct list_head	list;
215 	struct list_head	ipaddr_list;
216 	struct list_head	conn_list;
217 	struct ib_device	*dev;
218 	struct ib_pd		*pd;
219 	bool                    use_fastreg;
220 
221 	unsigned int		max_mrs;
222 	struct rds_ib_mr_pool	*mr_1m_pool;
223 	struct rds_ib_mr_pool   *mr_8k_pool;
224 	unsigned int		fmr_max_remaps;
225 	unsigned int		max_8k_mrs;
226 	unsigned int		max_1m_mrs;
227 	int			max_sge;
228 	unsigned int		max_wrs;
229 	unsigned int		max_initiator_depth;
230 	unsigned int		max_responder_resources;
231 	spinlock_t		spinlock;	/* protect the above */
232 	refcount_t		refcount;
233 	struct work_struct	free_work;
234 	int			*vector_load;
235 };
236 
237 #define ibdev_to_node(ibdev) dev_to_node((ibdev)->dev.parent)
238 #define rdsibdev_to_node(rdsibdev) ibdev_to_node(rdsibdev->dev)
239 
240 /* bits for i_ack_flags */
241 #define IB_ACK_IN_FLIGHT	0
242 #define IB_ACK_REQUESTED	1
243 
244 /* Magic WR_ID for ACKs */
245 #define RDS_IB_ACK_WR_ID	(~(u64) 0)
246 
247 struct rds_ib_statistics {
248 	uint64_t	s_ib_connect_raced;
249 	uint64_t	s_ib_listen_closed_stale;
250 	uint64_t	s_ib_evt_handler_call;
251 	uint64_t	s_ib_tasklet_call;
252 	uint64_t	s_ib_tx_cq_event;
253 	uint64_t	s_ib_tx_ring_full;
254 	uint64_t	s_ib_tx_throttle;
255 	uint64_t	s_ib_tx_sg_mapping_failure;
256 	uint64_t	s_ib_tx_stalled;
257 	uint64_t	s_ib_tx_credit_updates;
258 	uint64_t	s_ib_rx_cq_event;
259 	uint64_t	s_ib_rx_ring_empty;
260 	uint64_t	s_ib_rx_refill_from_cq;
261 	uint64_t	s_ib_rx_refill_from_thread;
262 	uint64_t	s_ib_rx_alloc_limit;
263 	uint64_t	s_ib_rx_total_frags;
264 	uint64_t	s_ib_rx_total_incs;
265 	uint64_t	s_ib_rx_credit_updates;
266 	uint64_t	s_ib_ack_sent;
267 	uint64_t	s_ib_ack_send_failure;
268 	uint64_t	s_ib_ack_send_delayed;
269 	uint64_t	s_ib_ack_send_piggybacked;
270 	uint64_t	s_ib_ack_received;
271 	uint64_t	s_ib_rdma_mr_8k_alloc;
272 	uint64_t	s_ib_rdma_mr_8k_free;
273 	uint64_t	s_ib_rdma_mr_8k_used;
274 	uint64_t	s_ib_rdma_mr_8k_pool_flush;
275 	uint64_t	s_ib_rdma_mr_8k_pool_wait;
276 	uint64_t	s_ib_rdma_mr_8k_pool_depleted;
277 	uint64_t	s_ib_rdma_mr_1m_alloc;
278 	uint64_t	s_ib_rdma_mr_1m_free;
279 	uint64_t	s_ib_rdma_mr_1m_used;
280 	uint64_t	s_ib_rdma_mr_1m_pool_flush;
281 	uint64_t	s_ib_rdma_mr_1m_pool_wait;
282 	uint64_t	s_ib_rdma_mr_1m_pool_depleted;
283 	uint64_t	s_ib_rdma_mr_8k_reused;
284 	uint64_t	s_ib_rdma_mr_1m_reused;
285 	uint64_t	s_ib_atomic_cswp;
286 	uint64_t	s_ib_atomic_fadd;
287 	uint64_t	s_ib_recv_added_to_cache;
288 	uint64_t	s_ib_recv_removed_from_cache;
289 };
290 
291 extern struct workqueue_struct *rds_ib_wq;
292 
293 /*
294  * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h
295  * doesn't define it.
296  */
297 static inline void rds_ib_dma_sync_sg_for_cpu(struct ib_device *dev,
298 					      struct scatterlist *sglist,
299 					      unsigned int sg_dma_len,
300 					      int direction)
301 {
302 	struct scatterlist *sg;
303 	unsigned int i;
304 
305 	for_each_sg(sglist, sg, sg_dma_len, i) {
306 		ib_dma_sync_single_for_cpu(dev,
307 				ib_sg_dma_address(dev, sg),
308 				ib_sg_dma_len(dev, sg),
309 				direction);
310 	}
311 }
312 #define ib_dma_sync_sg_for_cpu	rds_ib_dma_sync_sg_for_cpu
313 
314 static inline void rds_ib_dma_sync_sg_for_device(struct ib_device *dev,
315 						 struct scatterlist *sglist,
316 						 unsigned int sg_dma_len,
317 						 int direction)
318 {
319 	struct scatterlist *sg;
320 	unsigned int i;
321 
322 	for_each_sg(sglist, sg, sg_dma_len, i) {
323 		ib_dma_sync_single_for_device(dev,
324 				ib_sg_dma_address(dev, sg),
325 				ib_sg_dma_len(dev, sg),
326 				direction);
327 	}
328 }
329 #define ib_dma_sync_sg_for_device	rds_ib_dma_sync_sg_for_device
330 
331 
332 /* ib.c */
333 extern struct rds_transport rds_ib_transport;
334 struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device);
335 void rds_ib_dev_put(struct rds_ib_device *rds_ibdev);
336 extern struct ib_client rds_ib_client;
337 
338 extern unsigned int rds_ib_retry_count;
339 
340 extern spinlock_t ib_nodev_conns_lock;
341 extern struct list_head ib_nodev_conns;
342 
343 /* ib_cm.c */
344 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp);
345 void rds_ib_conn_free(void *arg);
346 int rds_ib_conn_path_connect(struct rds_conn_path *cp);
347 void rds_ib_conn_path_shutdown(struct rds_conn_path *cp);
348 void rds_ib_state_change(struct sock *sk);
349 int rds_ib_listen_init(void);
350 void rds_ib_listen_stop(void);
351 __printf(2, 3)
352 void __rds_ib_conn_error(struct rds_connection *conn, const char *, ...);
353 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
354 			     struct rdma_cm_event *event);
355 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id);
356 void rds_ib_cm_connect_complete(struct rds_connection *conn,
357 				struct rdma_cm_event *event);
358 
359 
360 #define rds_ib_conn_error(conn, fmt...) \
361 	__rds_ib_conn_error(conn, KERN_WARNING "RDS/IB: " fmt)
362 
363 /* ib_rdma.c */
364 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr);
365 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
366 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
367 void rds_ib_destroy_nodev_conns(void);
368 void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
369 
370 /* ib_recv.c */
371 int rds_ib_recv_init(void);
372 void rds_ib_recv_exit(void);
373 int rds_ib_recv_path(struct rds_conn_path *conn);
374 int rds_ib_recv_alloc_caches(struct rds_ib_connection *ic);
375 void rds_ib_recv_free_caches(struct rds_ib_connection *ic);
376 void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp);
377 void rds_ib_inc_free(struct rds_incoming *inc);
378 int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
379 void rds_ib_recv_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc,
380 			     struct rds_ib_ack_state *state);
381 void rds_ib_recv_tasklet_fn(unsigned long data);
382 void rds_ib_recv_init_ring(struct rds_ib_connection *ic);
383 void rds_ib_recv_clear_ring(struct rds_ib_connection *ic);
384 void rds_ib_recv_init_ack(struct rds_ib_connection *ic);
385 void rds_ib_attempt_ack(struct rds_ib_connection *ic);
386 void rds_ib_ack_send_complete(struct rds_ib_connection *ic);
387 u64 rds_ib_piggyb_ack(struct rds_ib_connection *ic);
388 void rds_ib_set_ack(struct rds_ib_connection *ic, u64 seq, int ack_required);
389 
390 /* ib_ring.c */
391 void rds_ib_ring_init(struct rds_ib_work_ring *ring, u32 nr);
392 void rds_ib_ring_resize(struct rds_ib_work_ring *ring, u32 nr);
393 u32 rds_ib_ring_alloc(struct rds_ib_work_ring *ring, u32 val, u32 *pos);
394 void rds_ib_ring_free(struct rds_ib_work_ring *ring, u32 val);
395 void rds_ib_ring_unalloc(struct rds_ib_work_ring *ring, u32 val);
396 int rds_ib_ring_empty(struct rds_ib_work_ring *ring);
397 int rds_ib_ring_low(struct rds_ib_work_ring *ring);
398 u32 rds_ib_ring_oldest(struct rds_ib_work_ring *ring);
399 u32 rds_ib_ring_completed(struct rds_ib_work_ring *ring, u32 wr_id, u32 oldest);
400 extern wait_queue_head_t rds_ib_ring_empty_wait;
401 
402 /* ib_send.c */
403 void rds_ib_xmit_path_complete(struct rds_conn_path *cp);
404 int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
405 		unsigned int hdr_off, unsigned int sg, unsigned int off);
406 void rds_ib_send_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
407 void rds_ib_send_init_ring(struct rds_ib_connection *ic);
408 void rds_ib_send_clear_ring(struct rds_ib_connection *ic);
409 int rds_ib_xmit_rdma(struct rds_connection *conn, struct rm_rdma_op *op);
410 void rds_ib_send_add_credits(struct rds_connection *conn, unsigned int credits);
411 void rds_ib_advertise_credits(struct rds_connection *conn, unsigned int posted);
412 int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
413 			     u32 *adv_credits, int need_posted, int max_posted);
414 int rds_ib_xmit_atomic(struct rds_connection *conn, struct rm_atomic_op *op);
415 
416 /* ib_stats.c */
417 DECLARE_PER_CPU(struct rds_ib_statistics, rds_ib_stats);
418 #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
419 #define rds_ib_stats_add(member, count) \
420 		rds_stats_add_which(rds_ib_stats, member, count)
421 unsigned int rds_ib_stats_info_copy(struct rds_info_iterator *iter,
422 				    unsigned int avail);
423 
424 /* ib_sysctl.c */
425 int rds_ib_sysctl_init(void);
426 void rds_ib_sysctl_exit(void);
427 extern unsigned long rds_ib_sysctl_max_send_wr;
428 extern unsigned long rds_ib_sysctl_max_recv_wr;
429 extern unsigned long rds_ib_sysctl_max_unsig_wrs;
430 extern unsigned long rds_ib_sysctl_max_unsig_bytes;
431 extern unsigned long rds_ib_sysctl_max_recv_allocation;
432 extern unsigned int rds_ib_sysctl_flow_control;
433 
434 #endif
435