xref: /openbmc/linux/net/rds/ib.h (revision 2c684d89)
1 #ifndef _RDS_IB_H
2 #define _RDS_IB_H
3 
4 #include <rdma/ib_verbs.h>
5 #include <rdma/rdma_cm.h>
6 #include <linux/interrupt.h>
7 #include <linux/pci.h>
8 #include <linux/slab.h>
9 #include "rds.h"
10 #include "rdma_transport.h"
11 
12 #define RDS_FMR_1M_POOL_SIZE		(8192 / 2)
13 #define RDS_FMR_1M_MSG_SIZE		256
14 #define RDS_FMR_8K_MSG_SIZE		2
15 #define RDS_MR_8K_SCALE			(256 / (RDS_FMR_8K_MSG_SIZE + 1))
16 #define RDS_FMR_8K_POOL_SIZE		(RDS_MR_8K_SCALE * (8192 / 2))
17 
18 #define RDS_IB_MAX_SGE			8
19 #define RDS_IB_RECV_SGE 		2
20 
21 #define RDS_IB_DEFAULT_RECV_WR		1024
22 #define RDS_IB_DEFAULT_SEND_WR		256
23 
24 #define RDS_IB_DEFAULT_RETRY_COUNT	2
25 
26 #define RDS_IB_SUPPORTED_PROTOCOLS	0x00000003	/* minor versions supported */
27 
28 #define RDS_IB_RECYCLE_BATCH_COUNT	32
29 
30 #define RDS_IB_WC_MAX			32
31 #define RDS_IB_SEND_OP			BIT_ULL(63)
32 
33 extern struct rw_semaphore rds_ib_devices_lock;
34 extern struct list_head rds_ib_devices;
35 
36 /*
37  * IB posts RDS_FRAG_SIZE fragments of pages to the receive queues to
38  * try and minimize the amount of memory tied up both the device and
39  * socket receive queues.
40  */
41 struct rds_page_frag {
42 	struct list_head	f_item;
43 	struct list_head	f_cache_entry;
44 	struct scatterlist	f_sg;
45 };
46 
47 struct rds_ib_incoming {
48 	struct list_head	ii_frags;
49 	struct list_head	ii_cache_entry;
50 	struct rds_incoming	ii_inc;
51 };
52 
53 struct rds_ib_cache_head {
54 	struct list_head *first;
55 	unsigned long count;
56 };
57 
58 struct rds_ib_refill_cache {
59 	struct rds_ib_cache_head __percpu *percpu;
60 	struct list_head	 *xfer;
61 	struct list_head	 *ready;
62 };
63 
64 struct rds_ib_connect_private {
65 	/* Add new fields at the end, and don't permute existing fields. */
66 	__be32			dp_saddr;
67 	__be32			dp_daddr;
68 	u8			dp_protocol_major;
69 	u8			dp_protocol_minor;
70 	__be16			dp_protocol_minor_mask; /* bitmask */
71 	__be32			dp_reserved1;
72 	__be64			dp_ack_seq;
73 	__be32			dp_credit;		/* non-zero enables flow ctl */
74 };
75 
76 struct rds_ib_send_work {
77 	void			*s_op;
78 	union {
79 		struct ib_send_wr	s_wr;
80 		struct ib_rdma_wr	s_rdma_wr;
81 		struct ib_atomic_wr	s_atomic_wr;
82 	};
83 	struct ib_sge		s_sge[RDS_IB_MAX_SGE];
84 	unsigned long		s_queued;
85 };
86 
87 struct rds_ib_recv_work {
88 	struct rds_ib_incoming 	*r_ibinc;
89 	struct rds_page_frag	*r_frag;
90 	struct ib_recv_wr	r_wr;
91 	struct ib_sge		r_sge[2];
92 };
93 
94 struct rds_ib_work_ring {
95 	u32		w_nr;
96 	u32		w_alloc_ptr;
97 	u32		w_alloc_ctr;
98 	u32		w_free_ptr;
99 	atomic_t	w_free_ctr;
100 };
101 
102 /* Rings are posted with all the allocations they'll need to queue the
103  * incoming message to the receiving socket so this can't fail.
104  * All fragments start with a header, so we can make sure we're not receiving
105  * garbage, and we can tell a small 8 byte fragment from an ACK frame.
106  */
107 struct rds_ib_ack_state {
108 	u64		ack_next;
109 	u64		ack_recv;
110 	unsigned int	ack_required:1;
111 	unsigned int	ack_next_valid:1;
112 	unsigned int	ack_recv_valid:1;
113 };
114 
115 
116 struct rds_ib_device;
117 
118 struct rds_ib_connection {
119 
120 	struct list_head	ib_node;
121 	struct rds_ib_device	*rds_ibdev;
122 	struct rds_connection	*conn;
123 
124 	/* alphabet soup, IBTA style */
125 	struct rdma_cm_id	*i_cm_id;
126 	struct ib_pd		*i_pd;
127 	struct ib_cq		*i_send_cq;
128 	struct ib_cq		*i_recv_cq;
129 	struct ib_wc		i_send_wc[RDS_IB_WC_MAX];
130 	struct ib_wc		i_recv_wc[RDS_IB_WC_MAX];
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 	u64			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 	u64			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 
156 	/* sending acks */
157 	unsigned long		i_ack_flags;
158 #ifdef KERNEL_HAS_ATOMIC64
159 	atomic64_t		i_ack_next;	/* next ACK to send */
160 #else
161 	spinlock_t		i_ack_lock;	/* protect i_ack_next */
162 	u64			i_ack_next;	/* next ACK to send */
163 #endif
164 	struct rds_header	*i_ack;
165 	struct ib_send_wr	i_ack_wr;
166 	struct ib_sge		i_ack_sge;
167 	u64			i_ack_dma;
168 	unsigned long		i_ack_queued;
169 
170 	/* Flow control related information
171 	 *
172 	 * Our algorithm uses a pair variables that we need to access
173 	 * atomically - one for the send credits, and one posted
174 	 * recv credits we need to transfer to remote.
175 	 * Rather than protect them using a slow spinlock, we put both into
176 	 * a single atomic_t and update it using cmpxchg
177 	 */
178 	atomic_t		i_credits;
179 
180 	/* Protocol version specific information */
181 	unsigned int		i_flowctl:1;	/* enable/disable flow ctl */
182 
183 	/* Batched completions */
184 	unsigned int		i_unsignaled_wrs;
185 };
186 
187 /* This assumes that atomic_t is at least 32 bits */
188 #define IB_GET_SEND_CREDITS(v)	((v) & 0xffff)
189 #define IB_GET_POST_CREDITS(v)	((v) >> 16)
190 #define IB_SET_SEND_CREDITS(v)	((v) & 0xffff)
191 #define IB_SET_POST_CREDITS(v)	((v) << 16)
192 
193 struct rds_ib_ipaddr {
194 	struct list_head	list;
195 	__be32			ipaddr;
196 	struct rcu_head		rcu;
197 };
198 
199 enum {
200 	RDS_IB_MR_8K_POOL,
201 	RDS_IB_MR_1M_POOL,
202 };
203 
204 struct rds_ib_device {
205 	struct list_head	list;
206 	struct list_head	ipaddr_list;
207 	struct list_head	conn_list;
208 	struct ib_device	*dev;
209 	struct ib_pd		*pd;
210 	unsigned int		max_fmrs;
211 	struct rds_ib_mr_pool	*mr_1m_pool;
212 	struct rds_ib_mr_pool   *mr_8k_pool;
213 	unsigned int		fmr_max_remaps;
214 	unsigned int		max_8k_fmrs;
215 	unsigned int		max_1m_fmrs;
216 	int			max_sge;
217 	unsigned int		max_wrs;
218 	unsigned int		max_initiator_depth;
219 	unsigned int		max_responder_resources;
220 	spinlock_t		spinlock;	/* protect the above */
221 	atomic_t		refcount;
222 	struct work_struct	free_work;
223 };
224 
225 #define ibdev_to_node(ibdev) dev_to_node(ibdev->dma_device)
226 #define rdsibdev_to_node(rdsibdev) ibdev_to_node(rdsibdev->dev)
227 
228 /* bits for i_ack_flags */
229 #define IB_ACK_IN_FLIGHT	0
230 #define IB_ACK_REQUESTED	1
231 
232 /* Magic WR_ID for ACKs */
233 #define RDS_IB_ACK_WR_ID	(~(u64) 0)
234 
235 struct rds_ib_statistics {
236 	uint64_t	s_ib_connect_raced;
237 	uint64_t	s_ib_listen_closed_stale;
238 	uint64_t	s_ib_evt_handler_call;
239 	uint64_t	s_ib_tasklet_call;
240 	uint64_t	s_ib_tx_cq_event;
241 	uint64_t	s_ib_tx_ring_full;
242 	uint64_t	s_ib_tx_throttle;
243 	uint64_t	s_ib_tx_sg_mapping_failure;
244 	uint64_t	s_ib_tx_stalled;
245 	uint64_t	s_ib_tx_credit_updates;
246 	uint64_t	s_ib_rx_cq_event;
247 	uint64_t	s_ib_rx_ring_empty;
248 	uint64_t	s_ib_rx_refill_from_cq;
249 	uint64_t	s_ib_rx_refill_from_thread;
250 	uint64_t	s_ib_rx_alloc_limit;
251 	uint64_t	s_ib_rx_credit_updates;
252 	uint64_t	s_ib_ack_sent;
253 	uint64_t	s_ib_ack_send_failure;
254 	uint64_t	s_ib_ack_send_delayed;
255 	uint64_t	s_ib_ack_send_piggybacked;
256 	uint64_t	s_ib_ack_received;
257 	uint64_t	s_ib_rdma_mr_8k_alloc;
258 	uint64_t	s_ib_rdma_mr_8k_free;
259 	uint64_t	s_ib_rdma_mr_8k_used;
260 	uint64_t	s_ib_rdma_mr_8k_pool_flush;
261 	uint64_t	s_ib_rdma_mr_8k_pool_wait;
262 	uint64_t	s_ib_rdma_mr_8k_pool_depleted;
263 	uint64_t	s_ib_rdma_mr_1m_alloc;
264 	uint64_t	s_ib_rdma_mr_1m_free;
265 	uint64_t	s_ib_rdma_mr_1m_used;
266 	uint64_t	s_ib_rdma_mr_1m_pool_flush;
267 	uint64_t	s_ib_rdma_mr_1m_pool_wait;
268 	uint64_t	s_ib_rdma_mr_1m_pool_depleted;
269 	uint64_t	s_ib_atomic_cswp;
270 	uint64_t	s_ib_atomic_fadd;
271 };
272 
273 extern struct workqueue_struct *rds_ib_wq;
274 
275 /*
276  * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h
277  * doesn't define it.
278  */
279 static inline void rds_ib_dma_sync_sg_for_cpu(struct ib_device *dev,
280 					      struct scatterlist *sglist,
281 					      unsigned int sg_dma_len,
282 					      int direction)
283 {
284 	struct scatterlist *sg;
285 	unsigned int i;
286 
287 	for_each_sg(sglist, sg, sg_dma_len, i) {
288 		ib_dma_sync_single_for_cpu(dev,
289 				ib_sg_dma_address(dev, sg),
290 				ib_sg_dma_len(dev, sg),
291 				direction);
292 	}
293 }
294 #define ib_dma_sync_sg_for_cpu	rds_ib_dma_sync_sg_for_cpu
295 
296 static inline void rds_ib_dma_sync_sg_for_device(struct ib_device *dev,
297 						 struct scatterlist *sglist,
298 						 unsigned int sg_dma_len,
299 						 int direction)
300 {
301 	struct scatterlist *sg;
302 	unsigned int i;
303 
304 	for_each_sg(sglist, sg, sg_dma_len, i) {
305 		ib_dma_sync_single_for_device(dev,
306 				ib_sg_dma_address(dev, sg),
307 				ib_sg_dma_len(dev, sg),
308 				direction);
309 	}
310 }
311 #define ib_dma_sync_sg_for_device	rds_ib_dma_sync_sg_for_device
312 
313 
314 /* ib.c */
315 extern struct rds_transport rds_ib_transport;
316 struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device);
317 void rds_ib_dev_put(struct rds_ib_device *rds_ibdev);
318 extern struct ib_client rds_ib_client;
319 
320 extern unsigned int rds_ib_fmr_1m_pool_size;
321 extern unsigned int rds_ib_fmr_8k_pool_size;
322 extern unsigned int rds_ib_retry_count;
323 
324 extern spinlock_t ib_nodev_conns_lock;
325 extern struct list_head ib_nodev_conns;
326 
327 /* ib_cm.c */
328 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp);
329 void rds_ib_conn_free(void *arg);
330 int rds_ib_conn_connect(struct rds_connection *conn);
331 void rds_ib_conn_shutdown(struct rds_connection *conn);
332 void rds_ib_state_change(struct sock *sk);
333 int rds_ib_listen_init(void);
334 void rds_ib_listen_stop(void);
335 void __rds_ib_conn_error(struct rds_connection *conn, const char *, ...);
336 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
337 			     struct rdma_cm_event *event);
338 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id);
339 void rds_ib_cm_connect_complete(struct rds_connection *conn,
340 				struct rdma_cm_event *event);
341 
342 
343 #define rds_ib_conn_error(conn, fmt...) \
344 	__rds_ib_conn_error(conn, KERN_WARNING "RDS/IB: " fmt)
345 
346 /* ib_rdma.c */
347 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr);
348 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
349 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
350 void rds_ib_destroy_nodev_conns(void);
351 struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_dev,
352 					     int npages);
353 void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_connection *iinfo);
354 void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *);
355 void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents,
356 		    struct rds_sock *rs, u32 *key_ret);
357 void rds_ib_sync_mr(void *trans_private, int dir);
358 void rds_ib_free_mr(void *trans_private, int invalidate);
359 void rds_ib_flush_mrs(void);
360 int rds_ib_fmr_init(void);
361 void rds_ib_fmr_exit(void);
362 
363 /* ib_recv.c */
364 int rds_ib_recv_init(void);
365 void rds_ib_recv_exit(void);
366 int rds_ib_recv(struct rds_connection *conn);
367 int rds_ib_recv_alloc_caches(struct rds_ib_connection *ic);
368 void rds_ib_recv_free_caches(struct rds_ib_connection *ic);
369 void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp);
370 void rds_ib_inc_free(struct rds_incoming *inc);
371 int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
372 void rds_ib_recv_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc,
373 			     struct rds_ib_ack_state *state);
374 void rds_ib_recv_tasklet_fn(unsigned long data);
375 void rds_ib_recv_init_ring(struct rds_ib_connection *ic);
376 void rds_ib_recv_clear_ring(struct rds_ib_connection *ic);
377 void rds_ib_recv_init_ack(struct rds_ib_connection *ic);
378 void rds_ib_attempt_ack(struct rds_ib_connection *ic);
379 void rds_ib_ack_send_complete(struct rds_ib_connection *ic);
380 u64 rds_ib_piggyb_ack(struct rds_ib_connection *ic);
381 void rds_ib_set_ack(struct rds_ib_connection *ic, u64 seq, int ack_required);
382 
383 /* ib_ring.c */
384 void rds_ib_ring_init(struct rds_ib_work_ring *ring, u32 nr);
385 void rds_ib_ring_resize(struct rds_ib_work_ring *ring, u32 nr);
386 u32 rds_ib_ring_alloc(struct rds_ib_work_ring *ring, u32 val, u32 *pos);
387 void rds_ib_ring_free(struct rds_ib_work_ring *ring, u32 val);
388 void rds_ib_ring_unalloc(struct rds_ib_work_ring *ring, u32 val);
389 int rds_ib_ring_empty(struct rds_ib_work_ring *ring);
390 int rds_ib_ring_low(struct rds_ib_work_ring *ring);
391 u32 rds_ib_ring_oldest(struct rds_ib_work_ring *ring);
392 u32 rds_ib_ring_completed(struct rds_ib_work_ring *ring, u32 wr_id, u32 oldest);
393 extern wait_queue_head_t rds_ib_ring_empty_wait;
394 
395 /* ib_send.c */
396 void rds_ib_xmit_complete(struct rds_connection *conn);
397 int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
398 		unsigned int hdr_off, unsigned int sg, unsigned int off);
399 void rds_ib_send_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
400 void rds_ib_send_init_ring(struct rds_ib_connection *ic);
401 void rds_ib_send_clear_ring(struct rds_ib_connection *ic);
402 int rds_ib_xmit_rdma(struct rds_connection *conn, struct rm_rdma_op *op);
403 void rds_ib_send_add_credits(struct rds_connection *conn, unsigned int credits);
404 void rds_ib_advertise_credits(struct rds_connection *conn, unsigned int posted);
405 int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
406 			     u32 *adv_credits, int need_posted, int max_posted);
407 int rds_ib_xmit_atomic(struct rds_connection *conn, struct rm_atomic_op *op);
408 
409 /* ib_stats.c */
410 DECLARE_PER_CPU(struct rds_ib_statistics, rds_ib_stats);
411 #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
412 unsigned int rds_ib_stats_info_copy(struct rds_info_iterator *iter,
413 				    unsigned int avail);
414 
415 /* ib_sysctl.c */
416 int rds_ib_sysctl_init(void);
417 void rds_ib_sysctl_exit(void);
418 extern unsigned long rds_ib_sysctl_max_send_wr;
419 extern unsigned long rds_ib_sysctl_max_recv_wr;
420 extern unsigned long rds_ib_sysctl_max_unsig_wrs;
421 extern unsigned long rds_ib_sysctl_max_unsig_bytes;
422 extern unsigned long rds_ib_sysctl_max_recv_allocation;
423 extern unsigned int rds_ib_sysctl_flow_control;
424 
425 #endif
426