xref: /openbmc/linux/net/rds/ib.h (revision 6a6d6681ac1add9655b7ab5dd0b46b54aeb1b44f)
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, gfp_t gfp);
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_SHARED_ALIGNED(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