xref: /openbmc/linux/net/rds/ib.h (revision e8e0929d)
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 "rds.h"
7 #include "rdma_transport.h"
8 
9 #define RDS_FMR_SIZE			256
10 #define RDS_FMR_POOL_SIZE		4096
11 
12 #define RDS_IB_MAX_SGE			8
13 #define RDS_IB_RECV_SGE 		2
14 
15 #define RDS_IB_DEFAULT_RECV_WR		1024
16 #define RDS_IB_DEFAULT_SEND_WR		256
17 
18 #define RDS_IB_DEFAULT_RETRY_COUNT	2
19 
20 #define RDS_IB_SUPPORTED_PROTOCOLS	0x00000003	/* minor versions supported */
21 
22 extern struct list_head rds_ib_devices;
23 
24 /*
25  * IB posts RDS_FRAG_SIZE fragments of pages to the receive queues to
26  * try and minimize the amount of memory tied up both the device and
27  * socket receive queues.
28  */
29 /* page offset of the final full frag that fits in the page */
30 #define RDS_PAGE_LAST_OFF (((PAGE_SIZE  / RDS_FRAG_SIZE) - 1) * RDS_FRAG_SIZE)
31 struct rds_page_frag {
32 	struct list_head	f_item;
33 	struct page		*f_page;
34 	unsigned long		f_offset;
35 	dma_addr_t 		f_mapped;
36 };
37 
38 struct rds_ib_incoming {
39 	struct list_head	ii_frags;
40 	struct rds_incoming	ii_inc;
41 };
42 
43 struct rds_ib_connect_private {
44 	/* Add new fields at the end, and don't permute existing fields. */
45 	__be32			dp_saddr;
46 	__be32			dp_daddr;
47 	u8			dp_protocol_major;
48 	u8			dp_protocol_minor;
49 	__be16			dp_protocol_minor_mask; /* bitmask */
50 	__be32			dp_reserved1;
51 	__be64			dp_ack_seq;
52 	__be32			dp_credit;		/* non-zero enables flow ctl */
53 };
54 
55 struct rds_ib_send_work {
56 	struct rds_message	*s_rm;
57 	struct rds_rdma_op	*s_op;
58 	struct ib_send_wr	s_wr;
59 	struct ib_sge		s_sge[RDS_IB_MAX_SGE];
60 	unsigned long		s_queued;
61 };
62 
63 struct rds_ib_recv_work {
64 	struct rds_ib_incoming 	*r_ibinc;
65 	struct rds_page_frag	*r_frag;
66 	struct ib_recv_wr	r_wr;
67 	struct ib_sge		r_sge[2];
68 };
69 
70 struct rds_ib_work_ring {
71 	u32		w_nr;
72 	u32		w_alloc_ptr;
73 	u32		w_alloc_ctr;
74 	u32		w_free_ptr;
75 	atomic_t	w_free_ctr;
76 };
77 
78 struct rds_ib_device;
79 
80 struct rds_ib_connection {
81 
82 	struct list_head	ib_node;
83 	struct rds_ib_device	*rds_ibdev;
84 	struct rds_connection	*conn;
85 
86 	/* alphabet soup, IBTA style */
87 	struct rdma_cm_id	*i_cm_id;
88 	struct ib_pd		*i_pd;
89 	struct ib_mr		*i_mr;
90 	struct ib_cq		*i_send_cq;
91 	struct ib_cq		*i_recv_cq;
92 
93 	/* tx */
94 	struct rds_ib_work_ring	i_send_ring;
95 	struct rds_message	*i_rm;
96 	struct rds_header	*i_send_hdrs;
97 	u64			i_send_hdrs_dma;
98 	struct rds_ib_send_work *i_sends;
99 
100 	/* rx */
101 	struct mutex		i_recv_mutex;
102 	struct rds_ib_work_ring	i_recv_ring;
103 	struct rds_ib_incoming	*i_ibinc;
104 	u32			i_recv_data_rem;
105 	struct rds_header	*i_recv_hdrs;
106 	u64			i_recv_hdrs_dma;
107 	struct rds_ib_recv_work *i_recvs;
108 	struct rds_page_frag	i_frag;
109 	u64			i_ack_recv;	/* last ACK received */
110 
111 	/* sending acks */
112 	unsigned long		i_ack_flags;
113 #ifdef KERNEL_HAS_ATOMIC64
114 	atomic64_t		i_ack_next;	/* next ACK to send */
115 #else
116 	spinlock_t		i_ack_lock;	/* protect i_ack_next */
117 	u64			i_ack_next;	/* next ACK to send */
118 #endif
119 	struct rds_header	*i_ack;
120 	struct ib_send_wr	i_ack_wr;
121 	struct ib_sge		i_ack_sge;
122 	u64			i_ack_dma;
123 	unsigned long		i_ack_queued;
124 
125 	/* Flow control related information
126 	 *
127 	 * Our algorithm uses a pair variables that we need to access
128 	 * atomically - one for the send credits, and one posted
129 	 * recv credits we need to transfer to remote.
130 	 * Rather than protect them using a slow spinlock, we put both into
131 	 * a single atomic_t and update it using cmpxchg
132 	 */
133 	atomic_t		i_credits;
134 
135 	/* Protocol version specific information */
136 	unsigned int		i_flowctl:1;	/* enable/disable flow ctl */
137 
138 	/* Batched completions */
139 	unsigned int		i_unsignaled_wrs;
140 	long			i_unsignaled_bytes;
141 };
142 
143 /* This assumes that atomic_t is at least 32 bits */
144 #define IB_GET_SEND_CREDITS(v)	((v) & 0xffff)
145 #define IB_GET_POST_CREDITS(v)	((v) >> 16)
146 #define IB_SET_SEND_CREDITS(v)	((v) & 0xffff)
147 #define IB_SET_POST_CREDITS(v)	((v) << 16)
148 
149 struct rds_ib_ipaddr {
150 	struct list_head	list;
151 	__be32			ipaddr;
152 };
153 
154 struct rds_ib_device {
155 	struct list_head	list;
156 	struct list_head	ipaddr_list;
157 	struct list_head	conn_list;
158 	struct ib_device	*dev;
159 	struct ib_pd		*pd;
160 	struct ib_mr		*mr;
161 	struct rds_ib_mr_pool	*mr_pool;
162 	unsigned int		fmr_max_remaps;
163 	unsigned int		max_fmrs;
164 	int			max_sge;
165 	unsigned int		max_wrs;
166 	spinlock_t		spinlock;	/* protect the above */
167 };
168 
169 /* bits for i_ack_flags */
170 #define IB_ACK_IN_FLIGHT	0
171 #define IB_ACK_REQUESTED	1
172 
173 /* Magic WR_ID for ACKs */
174 #define RDS_IB_ACK_WR_ID	(~(u64) 0)
175 
176 struct rds_ib_statistics {
177 	uint64_t	s_ib_connect_raced;
178 	uint64_t	s_ib_listen_closed_stale;
179 	uint64_t	s_ib_tx_cq_call;
180 	uint64_t	s_ib_tx_cq_event;
181 	uint64_t	s_ib_tx_ring_full;
182 	uint64_t	s_ib_tx_throttle;
183 	uint64_t	s_ib_tx_sg_mapping_failure;
184 	uint64_t	s_ib_tx_stalled;
185 	uint64_t	s_ib_tx_credit_updates;
186 	uint64_t	s_ib_rx_cq_call;
187 	uint64_t	s_ib_rx_cq_event;
188 	uint64_t	s_ib_rx_ring_empty;
189 	uint64_t	s_ib_rx_refill_from_cq;
190 	uint64_t	s_ib_rx_refill_from_thread;
191 	uint64_t	s_ib_rx_alloc_limit;
192 	uint64_t	s_ib_rx_credit_updates;
193 	uint64_t	s_ib_ack_sent;
194 	uint64_t	s_ib_ack_send_failure;
195 	uint64_t	s_ib_ack_send_delayed;
196 	uint64_t	s_ib_ack_send_piggybacked;
197 	uint64_t	s_ib_ack_received;
198 	uint64_t	s_ib_rdma_mr_alloc;
199 	uint64_t	s_ib_rdma_mr_free;
200 	uint64_t	s_ib_rdma_mr_used;
201 	uint64_t	s_ib_rdma_mr_pool_flush;
202 	uint64_t	s_ib_rdma_mr_pool_wait;
203 	uint64_t	s_ib_rdma_mr_pool_depleted;
204 };
205 
206 extern struct workqueue_struct *rds_ib_wq;
207 
208 /*
209  * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h
210  * doesn't define it.
211  */
212 static inline void rds_ib_dma_sync_sg_for_cpu(struct ib_device *dev,
213 		struct scatterlist *sg, unsigned int sg_dma_len, int direction)
214 {
215 	unsigned int i;
216 
217 	for (i = 0; i < sg_dma_len; ++i) {
218 		ib_dma_sync_single_for_cpu(dev,
219 				ib_sg_dma_address(dev, &sg[i]),
220 				ib_sg_dma_len(dev, &sg[i]),
221 				direction);
222 	}
223 }
224 #define ib_dma_sync_sg_for_cpu	rds_ib_dma_sync_sg_for_cpu
225 
226 static inline void rds_ib_dma_sync_sg_for_device(struct ib_device *dev,
227 		struct scatterlist *sg, unsigned int sg_dma_len, int direction)
228 {
229 	unsigned int i;
230 
231 	for (i = 0; i < sg_dma_len; ++i) {
232 		ib_dma_sync_single_for_device(dev,
233 				ib_sg_dma_address(dev, &sg[i]),
234 				ib_sg_dma_len(dev, &sg[i]),
235 				direction);
236 	}
237 }
238 #define ib_dma_sync_sg_for_device	rds_ib_dma_sync_sg_for_device
239 
240 
241 /* ib.c */
242 extern struct rds_transport rds_ib_transport;
243 extern void rds_ib_add_one(struct ib_device *device);
244 extern void rds_ib_remove_one(struct ib_device *device);
245 extern struct ib_client rds_ib_client;
246 
247 extern unsigned int fmr_pool_size;
248 extern unsigned int fmr_message_size;
249 extern unsigned int rds_ib_retry_count;
250 
251 extern spinlock_t ib_nodev_conns_lock;
252 extern struct list_head ib_nodev_conns;
253 
254 /* ib_cm.c */
255 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp);
256 void rds_ib_conn_free(void *arg);
257 int rds_ib_conn_connect(struct rds_connection *conn);
258 void rds_ib_conn_shutdown(struct rds_connection *conn);
259 void rds_ib_state_change(struct sock *sk);
260 int __init rds_ib_listen_init(void);
261 void rds_ib_listen_stop(void);
262 void __rds_ib_conn_error(struct rds_connection *conn, const char *, ...);
263 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
264 			     struct rdma_cm_event *event);
265 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id);
266 void rds_ib_cm_connect_complete(struct rds_connection *conn,
267 				struct rdma_cm_event *event);
268 
269 
270 #define rds_ib_conn_error(conn, fmt...) \
271 	__rds_ib_conn_error(conn, KERN_WARNING "RDS/IB: " fmt)
272 
273 /* ib_rdma.c */
274 int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr);
275 void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
276 void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
277 void __rds_ib_destroy_conns(struct list_head *list, spinlock_t *list_lock);
278 static inline void rds_ib_destroy_nodev_conns(void)
279 {
280 	__rds_ib_destroy_conns(&ib_nodev_conns, &ib_nodev_conns_lock);
281 }
282 static inline void rds_ib_destroy_conns(struct rds_ib_device *rds_ibdev)
283 {
284 	__rds_ib_destroy_conns(&rds_ibdev->conn_list, &rds_ibdev->spinlock);
285 }
286 struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *);
287 void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_connection *iinfo);
288 void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *);
289 void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents,
290 		    struct rds_sock *rs, u32 *key_ret);
291 void rds_ib_sync_mr(void *trans_private, int dir);
292 void rds_ib_free_mr(void *trans_private, int invalidate);
293 void rds_ib_flush_mrs(void);
294 
295 /* ib_recv.c */
296 int __init rds_ib_recv_init(void);
297 void rds_ib_recv_exit(void);
298 int rds_ib_recv(struct rds_connection *conn);
299 int rds_ib_recv_refill(struct rds_connection *conn, gfp_t kptr_gfp,
300 		       gfp_t page_gfp, int prefill);
301 void rds_ib_inc_purge(struct rds_incoming *inc);
302 void rds_ib_inc_free(struct rds_incoming *inc);
303 int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iovec *iov,
304 			     size_t size);
305 void rds_ib_recv_cq_comp_handler(struct ib_cq *cq, void *context);
306 void rds_ib_recv_init_ring(struct rds_ib_connection *ic);
307 void rds_ib_recv_clear_ring(struct rds_ib_connection *ic);
308 void rds_ib_recv_init_ack(struct rds_ib_connection *ic);
309 void rds_ib_attempt_ack(struct rds_ib_connection *ic);
310 void rds_ib_ack_send_complete(struct rds_ib_connection *ic);
311 u64 rds_ib_piggyb_ack(struct rds_ib_connection *ic);
312 
313 /* ib_ring.c */
314 void rds_ib_ring_init(struct rds_ib_work_ring *ring, u32 nr);
315 void rds_ib_ring_resize(struct rds_ib_work_ring *ring, u32 nr);
316 u32 rds_ib_ring_alloc(struct rds_ib_work_ring *ring, u32 val, u32 *pos);
317 void rds_ib_ring_free(struct rds_ib_work_ring *ring, u32 val);
318 void rds_ib_ring_unalloc(struct rds_ib_work_ring *ring, u32 val);
319 int rds_ib_ring_empty(struct rds_ib_work_ring *ring);
320 int rds_ib_ring_low(struct rds_ib_work_ring *ring);
321 u32 rds_ib_ring_oldest(struct rds_ib_work_ring *ring);
322 u32 rds_ib_ring_completed(struct rds_ib_work_ring *ring, u32 wr_id, u32 oldest);
323 extern wait_queue_head_t rds_ib_ring_empty_wait;
324 
325 /* ib_send.c */
326 void rds_ib_xmit_complete(struct rds_connection *conn);
327 int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
328 		unsigned int hdr_off, unsigned int sg, unsigned int off);
329 void rds_ib_send_cq_comp_handler(struct ib_cq *cq, void *context);
330 void rds_ib_send_init_ring(struct rds_ib_connection *ic);
331 void rds_ib_send_clear_ring(struct rds_ib_connection *ic);
332 int rds_ib_xmit_rdma(struct rds_connection *conn, struct rds_rdma_op *op);
333 void rds_ib_send_add_credits(struct rds_connection *conn, unsigned int credits);
334 void rds_ib_advertise_credits(struct rds_connection *conn, unsigned int posted);
335 int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
336 			     u32 *adv_credits, int need_posted, int max_posted);
337 
338 /* ib_stats.c */
339 DECLARE_PER_CPU(struct rds_ib_statistics, rds_ib_stats);
340 #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
341 unsigned int rds_ib_stats_info_copy(struct rds_info_iterator *iter,
342 				    unsigned int avail);
343 
344 /* ib_sysctl.c */
345 int __init rds_ib_sysctl_init(void);
346 void rds_ib_sysctl_exit(void);
347 extern unsigned long rds_ib_sysctl_max_send_wr;
348 extern unsigned long rds_ib_sysctl_max_recv_wr;
349 extern unsigned long rds_ib_sysctl_max_unsig_wrs;
350 extern unsigned long rds_ib_sysctl_max_unsig_bytes;
351 extern unsigned long rds_ib_sysctl_max_recv_allocation;
352 extern unsigned int rds_ib_sysctl_flow_control;
353 extern ctl_table rds_ib_sysctl_table[];
354 
355 /*
356  * Helper functions for getting/setting the header and data SGEs in
357  * RDS packets (not RDMA)
358  *
359  * From version 3.1 onwards, header is in front of data in the sge.
360  */
361 static inline struct ib_sge *
362 rds_ib_header_sge(struct rds_ib_connection *ic, struct ib_sge *sge)
363 {
364 	if (ic->conn->c_version > RDS_PROTOCOL_3_0)
365 		return &sge[0];
366 	else
367 		return &sge[1];
368 }
369 
370 static inline struct ib_sge *
371 rds_ib_data_sge(struct rds_ib_connection *ic, struct ib_sge *sge)
372 {
373 	if (ic->conn->c_version > RDS_PROTOCOL_3_0)
374 		return &sge[1];
375 	else
376 		return &sge[0];
377 }
378 
379 #endif
380