xref: /linux/net/smc/smc_core.h (revision 9406b485dea5e25bed7c81cd822747d494cc8bde)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  Definitions for SMC Connections, Link Groups and Links
6  *
7  *  Copyright IBM Corp. 2016
8  *
9  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
10  */
11 
12 #ifndef _SMC_CORE_H
13 #define _SMC_CORE_H
14 
15 #include <linux/atomic.h>
16 #include <rdma/ib_verbs.h>
17 
18 #include "smc.h"
19 #include "smc_ib.h"
20 
21 #define SMC_RMBS_PER_LGR_MAX	255	/* max. # of RMBs per link group */
22 
23 struct smc_lgr_list {			/* list of link group definition */
24 	struct list_head	list;
25 	spinlock_t		lock;	/* protects list of link groups */
26 	u32			num;	/* unique link group number */
27 };
28 
29 enum smc_lgr_role {		/* possible roles of a link group */
30 	SMC_CLNT,	/* client */
31 	SMC_SERV	/* server */
32 };
33 
34 enum smc_link_state {			/* possible states of a link */
35 	SMC_LNK_UNUSED,		/* link is unused */
36 	SMC_LNK_INACTIVE,	/* link is inactive */
37 	SMC_LNK_ACTIVATING,	/* link is being activated */
38 	SMC_LNK_ACTIVE,		/* link is active */
39 };
40 
41 #define SMC_WR_BUF_SIZE		48	/* size of work request buffer */
42 
43 struct smc_wr_buf {
44 	u8	raw[SMC_WR_BUF_SIZE];
45 };
46 
47 #define SMC_WR_REG_MR_WAIT_TIME	(5 * HZ)/* wait time for ib_wr_reg_mr result */
48 
49 enum smc_wr_reg_state {
50 	POSTED,		/* ib_wr_reg_mr request posted */
51 	CONFIRMED,	/* ib_wr_reg_mr response: successful */
52 	FAILED		/* ib_wr_reg_mr response: failure */
53 };
54 
55 struct smc_rdma_sge {				/* sges for RDMA writes */
56 	struct ib_sge		wr_tx_rdma_sge[SMC_IB_MAX_SEND_SGE];
57 };
58 
59 #define SMC_MAX_RDMA_WRITES	2		/* max. # of RDMA writes per
60 						 * message send
61 						 */
62 
63 struct smc_rdma_sges {				/* sges per message send */
64 	struct smc_rdma_sge	tx_rdma_sge[SMC_MAX_RDMA_WRITES];
65 };
66 
67 struct smc_rdma_wr {				/* work requests per message
68 						 * send
69 						 */
70 	struct ib_rdma_wr	wr_tx_rdma[SMC_MAX_RDMA_WRITES];
71 };
72 
73 struct smc_link {
74 	struct smc_ib_device	*smcibdev;	/* ib-device */
75 	u8			ibport;		/* port - values 1 | 2 */
76 	struct ib_pd		*roce_pd;	/* IB protection domain,
77 						 * unique for every RoCE QP
78 						 */
79 	struct ib_qp		*roce_qp;	/* IB queue pair */
80 	struct ib_qp_attr	qp_attr;	/* IB queue pair attributes */
81 
82 	struct smc_wr_buf	*wr_tx_bufs;	/* WR send payload buffers */
83 	struct ib_send_wr	*wr_tx_ibs;	/* WR send meta data */
84 	struct ib_sge		*wr_tx_sges;	/* WR send gather meta data */
85 	struct smc_rdma_sges	*wr_tx_rdma_sges;/*RDMA WRITE gather meta data*/
86 	struct smc_rdma_wr	*wr_tx_rdmas;	/* WR RDMA WRITE */
87 	struct smc_wr_tx_pend	*wr_tx_pends;	/* WR send waiting for CQE */
88 	/* above four vectors have wr_tx_cnt elements and use the same index */
89 	dma_addr_t		wr_tx_dma_addr;	/* DMA address of wr_tx_bufs */
90 	atomic_long_t		wr_tx_id;	/* seq # of last sent WR */
91 	unsigned long		*wr_tx_mask;	/* bit mask of used indexes */
92 	u32			wr_tx_cnt;	/* number of WR send buffers */
93 	wait_queue_head_t	wr_tx_wait;	/* wait for free WR send buf */
94 
95 	struct smc_wr_buf	*wr_rx_bufs;	/* WR recv payload buffers */
96 	struct ib_recv_wr	*wr_rx_ibs;	/* WR recv meta data */
97 	struct ib_sge		*wr_rx_sges;	/* WR recv scatter meta data */
98 	/* above three vectors have wr_rx_cnt elements and use the same index */
99 	dma_addr_t		wr_rx_dma_addr;	/* DMA address of wr_rx_bufs */
100 	u64			wr_rx_id;	/* seq # of last recv WR */
101 	u32			wr_rx_cnt;	/* number of WR recv buffers */
102 	unsigned long		wr_rx_tstamp;	/* jiffies when last buf rx */
103 
104 	struct ib_reg_wr	wr_reg;		/* WR register memory region */
105 	wait_queue_head_t	wr_reg_wait;	/* wait for wr_reg result */
106 	enum smc_wr_reg_state	wr_reg_state;	/* state of wr_reg request */
107 
108 	u8			gid[SMC_GID_SIZE];/* gid matching used vlan id*/
109 	u8			sgid_index;	/* gid index for vlan id      */
110 	u32			peer_qpn;	/* QP number of peer */
111 	enum ib_mtu		path_mtu;	/* used mtu */
112 	enum ib_mtu		peer_mtu;	/* mtu size of peer */
113 	u32			psn_initial;	/* QP tx initial packet seqno */
114 	u32			peer_psn;	/* QP rx initial packet seqno */
115 	u8			peer_mac[ETH_ALEN];	/* = gid[8:10||13:15] */
116 	u8			peer_gid[SMC_GID_SIZE];	/* gid of peer*/
117 	u8			link_id;	/* unique # within link group */
118 	u8			link_idx;	/* index in lgr link array */
119 	struct smc_link_group	*lgr;		/* parent link group */
120 	struct work_struct	link_down_wrk;	/* wrk to bring link down */
121 
122 	enum smc_link_state	state;		/* state of link */
123 	struct delayed_work	llc_testlink_wrk; /* testlink worker */
124 	struct completion	llc_testlink_resp; /* wait for rx of testlink */
125 	int			llc_testlink_time; /* testlink interval */
126 };
127 
128 /* For now we just allow one parallel link per link group. The SMC protocol
129  * allows more (up to 8).
130  */
131 #define SMC_LINKS_PER_LGR_MAX	3
132 #define SMC_SINGLE_LINK		0
133 
134 #define SMC_FIRST_CONTACT	1		/* first contact to a peer */
135 #define SMC_REUSE_CONTACT	0		/* follow-on contact to a peer*/
136 
137 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
138 struct smc_buf_desc {
139 	struct list_head	list;
140 	void			*cpu_addr;	/* virtual address of buffer */
141 	struct page		*pages;
142 	int			len;		/* length of buffer */
143 	u32			used;		/* currently used / unused */
144 	union {
145 		struct { /* SMC-R */
146 			struct sg_table	sgt[SMC_LINKS_PER_LGR_MAX];
147 					/* virtual buffer */
148 			struct ib_mr	*mr_rx[SMC_LINKS_PER_LGR_MAX];
149 					/* for rmb only: memory region
150 					 * incl. rkey provided to peer
151 					 */
152 			u32		order;	/* allocation order */
153 
154 			u8		is_conf_rkey;
155 					/* confirm_rkey done */
156 			u8		is_reg_mr[SMC_LINKS_PER_LGR_MAX];
157 					/* mem region registered */
158 			u8		is_map_ib[SMC_LINKS_PER_LGR_MAX];
159 					/* mem region mapped to lnk */
160 			u8		is_reg_err;
161 					/* buffer registration err */
162 		};
163 		struct { /* SMC-D */
164 			unsigned short	sba_idx;
165 					/* SBA index number */
166 			u64		token;
167 					/* DMB token number */
168 			dma_addr_t	dma_addr;
169 					/* DMA address */
170 		};
171 	};
172 };
173 
174 struct smc_rtoken {				/* address/key of remote RMB */
175 	u64			dma_addr;
176 	u32			rkey;
177 };
178 
179 #define SMC_LGR_ID_SIZE		4
180 #define SMC_BUF_MIN_SIZE	16384	/* minimum size of an RMB */
181 #define SMC_RMBE_SIZES		16	/* number of distinct RMBE sizes */
182 /* theoretically, the RFC states that largest size would be 512K,
183  * i.e. compressed 5 and thus 6 sizes (0..5), despite
184  * struct smc_clc_msg_accept_confirm.rmbe_size being a 4 bit value (0..15)
185  */
186 
187 struct smcd_dev;
188 
189 enum smc_lgr_type {				/* redundancy state of lgr */
190 	SMC_LGR_NONE,			/* no active links, lgr to be deleted */
191 	SMC_LGR_SINGLE,			/* 1 active RNIC on each peer */
192 	SMC_LGR_SYMMETRIC,		/* 2 active RNICs on each peer */
193 	SMC_LGR_ASYMMETRIC_PEER,	/* local has 2, peer 1 active RNICs */
194 	SMC_LGR_ASYMMETRIC_LOCAL,	/* local has 1, peer 2 active RNICs */
195 };
196 
197 enum smc_llc_flowtype {
198 	SMC_LLC_FLOW_NONE	= 0,
199 	SMC_LLC_FLOW_ADD_LINK	= 2,
200 	SMC_LLC_FLOW_DEL_LINK	= 4,
201 	SMC_LLC_FLOW_RKEY	= 6,
202 };
203 
204 struct smc_llc_qentry;
205 
206 struct smc_llc_flow {
207 	enum smc_llc_flowtype type;
208 	struct smc_llc_qentry *qentry;
209 };
210 
211 struct smc_link_group {
212 	struct list_head	list;
213 	struct rb_root		conns_all;	/* connection tree */
214 	rwlock_t		conns_lock;	/* protects conns_all */
215 	unsigned int		conns_num;	/* current # of connections */
216 	unsigned short		vlan_id;	/* vlan id of link group */
217 
218 	struct list_head	sndbufs[SMC_RMBE_SIZES];/* tx buffers */
219 	struct mutex		sndbufs_lock;	/* protects tx buffers */
220 	struct list_head	rmbs[SMC_RMBE_SIZES];	/* rx buffers */
221 	struct mutex		rmbs_lock;	/* protects rx buffers */
222 
223 	u8			id[SMC_LGR_ID_SIZE];	/* unique lgr id */
224 	struct delayed_work	free_work;	/* delayed freeing of an lgr */
225 	struct work_struct	terminate_work;	/* abnormal lgr termination */
226 	u8			sync_err : 1;	/* lgr no longer fits to peer */
227 	u8			terminating : 1;/* lgr is terminating */
228 	u8			freefast : 1;	/* free worker scheduled fast */
229 	u8			freeing : 1;	/* lgr is being freed */
230 
231 	bool			is_smcd;	/* SMC-R or SMC-D */
232 	union {
233 		struct { /* SMC-R */
234 			enum smc_lgr_role	role;
235 						/* client or server */
236 			struct smc_link		lnk[SMC_LINKS_PER_LGR_MAX];
237 						/* smc link */
238 			char			peer_systemid[SMC_SYSTEMID_LEN];
239 						/* unique system_id of peer */
240 			struct smc_rtoken	rtokens[SMC_RMBS_PER_LGR_MAX]
241 						[SMC_LINKS_PER_LGR_MAX];
242 						/* remote addr/key pairs */
243 			DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
244 						/* used rtoken elements */
245 			u8			next_link_id;
246 			enum smc_lgr_type	type;
247 						/* redundancy state */
248 			u8			pnet_id[SMC_MAX_PNETID_LEN + 1];
249 						/* pnet id of this lgr */
250 			struct list_head	llc_event_q;
251 						/* queue for llc events */
252 			spinlock_t		llc_event_q_lock;
253 						/* protects llc_event_q */
254 			struct mutex		llc_conf_mutex;
255 						/* protects lgr reconfig. */
256 			struct work_struct	llc_add_link_work;
257 			struct work_struct	llc_del_link_work;
258 			struct work_struct	llc_event_work;
259 						/* llc event worker */
260 			wait_queue_head_t	llc_waiter;
261 						/* w4 next llc event */
262 			struct smc_llc_flow	llc_flow_lcl;
263 						/* llc local control field */
264 			struct smc_llc_flow	llc_flow_rmt;
265 						/* llc remote control field */
266 			struct smc_llc_qentry	*delayed_event;
267 						/* arrived when flow active */
268 			spinlock_t		llc_flow_lock;
269 						/* protects llc flow */
270 			int			llc_testlink_time;
271 						/* link keep alive time */
272 		};
273 		struct { /* SMC-D */
274 			u64			peer_gid;
275 						/* Peer GID (remote) */
276 			struct smcd_dev		*smcd;
277 						/* ISM device for VLAN reg. */
278 			u8			peer_shutdown : 1;
279 						/* peer triggered shutdownn */
280 		};
281 	};
282 };
283 
284 struct smc_clc_msg_local;
285 
286 struct smc_init_info {
287 	u8			is_smcd;
288 	unsigned short		vlan_id;
289 	int			srv_first_contact;
290 	int			cln_first_contact;
291 	/* SMC-R */
292 	struct smc_clc_msg_local *ib_lcl;
293 	struct smc_ib_device	*ib_dev;
294 	u8			ib_gid[SMC_GID_SIZE];
295 	u8			ib_port;
296 	u32			ib_clcqpn;
297 	/* SMC-D */
298 	u64			ism_gid;
299 	struct smcd_dev		*ism_dev;
300 };
301 
302 /* Find the connection associated with the given alert token in the link group.
303  * To use rbtrees we have to implement our own search core.
304  * Requires @conns_lock
305  * @token	alert token to search for
306  * @lgr		 link group to search in
307  * Returns connection associated with token if found, NULL otherwise.
308  */
309 static inline struct smc_connection *smc_lgr_find_conn(
310 	u32 token, struct smc_link_group *lgr)
311 {
312 	struct smc_connection *res = NULL;
313 	struct rb_node *node;
314 
315 	node = lgr->conns_all.rb_node;
316 	while (node) {
317 		struct smc_connection *cur = rb_entry(node,
318 					struct smc_connection, alert_node);
319 
320 		if (cur->alert_token_local > token) {
321 			node = node->rb_left;
322 		} else {
323 			if (cur->alert_token_local < token) {
324 				node = node->rb_right;
325 			} else {
326 				res = cur;
327 				break;
328 			}
329 		}
330 	}
331 
332 	return res;
333 }
334 
335 /* returns true if the specified link is usable */
336 static inline bool smc_link_usable(struct smc_link *lnk)
337 {
338 	if (lnk->state == SMC_LNK_UNUSED || lnk->state == SMC_LNK_INACTIVE)
339 		return false;
340 	return true;
341 }
342 
343 struct smc_sock;
344 struct smc_clc_msg_accept_confirm;
345 struct smc_clc_msg_local;
346 
347 void smc_lgr_cleanup_early(struct smc_connection *conn);
348 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
349 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
350 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport);
351 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
352 			unsigned short vlan);
353 void smc_smcd_terminate_all(struct smcd_dev *dev);
354 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
355 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
356 int smc_uncompress_bufsize(u8 compressed);
357 int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_link *link,
358 			    struct smc_clc_msg_accept_confirm *clc);
359 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey);
360 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey);
361 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
362 		    __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey);
363 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
364 		     __be64 nw_vaddr, __be32 nw_rkey);
365 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
366 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
367 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
368 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
369 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini);
370 
371 void smc_conn_free(struct smc_connection *conn);
372 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini);
373 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr);
374 int smc_core_init(void);
375 void smc_core_exit(void);
376 
377 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
378 		   u8 link_idx, struct smc_init_info *ini);
379 void smcr_link_clear(struct smc_link *lnk);
380 int smcr_buf_map_lgr(struct smc_link *lnk);
381 int smcr_buf_reg_lgr(struct smc_link *lnk);
382 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc);
383 void smcr_link_down_cond(struct smc_link *lnk);
384 void smcr_link_down_cond_sched(struct smc_link *lnk);
385 
386 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
387 {
388 	return link->lgr;
389 }
390 #endif
391