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  	u8			odp_capable:1;
250  
251  	unsigned int		max_mrs;
252  	struct rds_ib_mr_pool	*mr_1m_pool;
253  	struct rds_ib_mr_pool   *mr_8k_pool;
254  	unsigned int		max_8k_mrs;
255  	unsigned int		max_1m_mrs;
256  	int			max_sge;
257  	unsigned int		max_wrs;
258  	unsigned int		max_initiator_depth;
259  	unsigned int		max_responder_resources;
260  	spinlock_t		spinlock;	/* protect the above */
261  	refcount_t		refcount;
262  	struct work_struct	free_work;
263  	int			*vector_load;
264  };
265  
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   */
rds_ib_dma_sync_sg_for_cpu(struct ib_device * dev,struct scatterlist * sglist,unsigned int sg_dma_len,int direction)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, sg_dma_address(sg),
335  					   sg_dma_len(sg), direction);
336  	}
337  }
338  #define ib_dma_sync_sg_for_cpu	rds_ib_dma_sync_sg_for_cpu
339  
rds_ib_dma_sync_sg_for_device(struct ib_device * dev,struct scatterlist * sglist,unsigned int sg_dma_len,int direction)340  static inline void rds_ib_dma_sync_sg_for_device(struct ib_device *dev,
341  						 struct scatterlist *sglist,
342  						 unsigned int sg_dma_len,
343  						 int direction)
344  {
345  	struct scatterlist *sg;
346  	unsigned int i;
347  
348  	for_each_sg(sglist, sg, sg_dma_len, i) {
349  		ib_dma_sync_single_for_device(dev, sg_dma_address(sg),
350  					      sg_dma_len(sg), direction);
351  	}
352  }
353  #define ib_dma_sync_sg_for_device	rds_ib_dma_sync_sg_for_device
354  
355  
356  /* ib.c */
357  extern struct rds_transport rds_ib_transport;
358  struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device);
359  void rds_ib_dev_put(struct rds_ib_device *rds_ibdev);
360  extern struct ib_client rds_ib_client;
361  
362  extern unsigned int rds_ib_retry_count;
363  
364  extern spinlock_t ib_nodev_conns_lock;
365  extern struct list_head ib_nodev_conns;
366  
367  /* ib_cm.c */
368  int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp);
369  void rds_ib_conn_free(void *arg);
370  int rds_ib_conn_path_connect(struct rds_conn_path *cp);
371  void rds_ib_conn_path_shutdown(struct rds_conn_path *cp);
372  __printf(2, 3)
373  void __rds_ib_conn_error(struct rds_connection *conn, const char *, ...);
374  int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
375  			     struct rdma_cm_event *event, bool isv6);
376  int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id, bool isv6);
377  void rds_ib_cm_connect_complete(struct rds_connection *conn,
378  				struct rdma_cm_event *event);
379  
380  #define rds_ib_conn_error(conn, fmt...) \
381  	__rds_ib_conn_error(conn, KERN_WARNING "RDS/IB: " fmt)
382  
383  /* ib_rdma.c */
384  int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev,
385  			 struct in6_addr *ipaddr);
386  void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
387  void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn);
388  void rds_ib_destroy_nodev_conns(void);
389  void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
390  
391  /* ib_recv.c */
392  int rds_ib_recv_init(void);
393  void rds_ib_recv_exit(void);
394  int rds_ib_recv_path(struct rds_conn_path *conn);
395  int rds_ib_recv_alloc_caches(struct rds_ib_connection *ic, gfp_t gfp);
396  void rds_ib_recv_free_caches(struct rds_ib_connection *ic);
397  void rds_ib_recv_refill(struct rds_connection *conn, int prefill, gfp_t gfp);
398  void rds_ib_inc_free(struct rds_incoming *inc);
399  int rds_ib_inc_copy_to_user(struct rds_incoming *inc, struct iov_iter *to);
400  void rds_ib_recv_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc,
401  			     struct rds_ib_ack_state *state);
402  void rds_ib_recv_init_ring(struct rds_ib_connection *ic);
403  void rds_ib_recv_clear_ring(struct rds_ib_connection *ic);
404  void rds_ib_recv_init_ack(struct rds_ib_connection *ic);
405  void rds_ib_attempt_ack(struct rds_ib_connection *ic);
406  void rds_ib_ack_send_complete(struct rds_ib_connection *ic);
407  u64 rds_ib_piggyb_ack(struct rds_ib_connection *ic);
408  void rds_ib_set_ack(struct rds_ib_connection *ic, u64 seq, int ack_required);
409  
410  /* ib_ring.c */
411  void rds_ib_ring_init(struct rds_ib_work_ring *ring, u32 nr);
412  void rds_ib_ring_resize(struct rds_ib_work_ring *ring, u32 nr);
413  u32 rds_ib_ring_alloc(struct rds_ib_work_ring *ring, u32 val, u32 *pos);
414  void rds_ib_ring_free(struct rds_ib_work_ring *ring, u32 val);
415  void rds_ib_ring_unalloc(struct rds_ib_work_ring *ring, u32 val);
416  int rds_ib_ring_empty(struct rds_ib_work_ring *ring);
417  int rds_ib_ring_low(struct rds_ib_work_ring *ring);
418  u32 rds_ib_ring_oldest(struct rds_ib_work_ring *ring);
419  u32 rds_ib_ring_completed(struct rds_ib_work_ring *ring, u32 wr_id, u32 oldest);
420  extern wait_queue_head_t rds_ib_ring_empty_wait;
421  
422  /* ib_send.c */
423  void rds_ib_xmit_path_complete(struct rds_conn_path *cp);
424  int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
425  		unsigned int hdr_off, unsigned int sg, unsigned int off);
426  void rds_ib_send_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc);
427  void rds_ib_send_init_ring(struct rds_ib_connection *ic);
428  void rds_ib_send_clear_ring(struct rds_ib_connection *ic);
429  int rds_ib_xmit_rdma(struct rds_connection *conn, struct rm_rdma_op *op);
430  void rds_ib_send_add_credits(struct rds_connection *conn, unsigned int credits);
431  void rds_ib_advertise_credits(struct rds_connection *conn, unsigned int posted);
432  int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
433  			     u32 *adv_credits, int need_posted, int max_posted);
434  int rds_ib_xmit_atomic(struct rds_connection *conn, struct rm_atomic_op *op);
435  
436  /* ib_stats.c */
437  DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_ib_statistics, rds_ib_stats);
438  #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
439  #define rds_ib_stats_add(member, count) \
440  		rds_stats_add_which(rds_ib_stats, member, count)
441  unsigned int rds_ib_stats_info_copy(struct rds_info_iterator *iter,
442  				    unsigned int avail);
443  
444  /* ib_sysctl.c */
445  int rds_ib_sysctl_init(void);
446  void rds_ib_sysctl_exit(void);
447  extern unsigned long rds_ib_sysctl_max_send_wr;
448  extern unsigned long rds_ib_sysctl_max_recv_wr;
449  extern unsigned long rds_ib_sysctl_max_unsig_wrs;
450  extern unsigned long rds_ib_sysctl_max_unsig_bytes;
451  extern unsigned long rds_ib_sysctl_max_recv_allocation;
452  extern unsigned int rds_ib_sysctl_flow_control;
453  
454  #endif
455