xref: /linux/net/smc/smc_core.h (revision 40e79150c1686263e6a031d7702aec63aff31332)
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 
121 	enum smc_link_state	state;		/* state of link */
122 	struct delayed_work	llc_testlink_wrk; /* testlink worker */
123 	struct completion	llc_testlink_resp; /* wait for rx of testlink */
124 	int			llc_testlink_time; /* testlink interval */
125 };
126 
127 /* For now we just allow one parallel link per link group. The SMC protocol
128  * allows more (up to 8).
129  */
130 #define SMC_LINKS_PER_LGR_MAX	1
131 #define SMC_SINGLE_LINK		0
132 
133 #define SMC_FIRST_CONTACT	1		/* first contact to a peer */
134 #define SMC_REUSE_CONTACT	0		/* follow-on contact to a peer*/
135 
136 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
137 struct smc_buf_desc {
138 	struct list_head	list;
139 	void			*cpu_addr;	/* virtual address of buffer */
140 	struct page		*pages;
141 	int			len;		/* length of buffer */
142 	u32			used;		/* currently used / unused */
143 	union {
144 		struct { /* SMC-R */
145 			struct sg_table	sgt[SMC_LINKS_PER_LGR_MAX];
146 					/* virtual buffer */
147 			struct ib_mr	*mr_rx[SMC_LINKS_PER_LGR_MAX];
148 					/* for rmb only: memory region
149 					 * incl. rkey provided to peer
150 					 */
151 			u32		order;	/* allocation order */
152 
153 			u8		is_conf_rkey;
154 					/* confirm_rkey done */
155 			u8		is_reg_mr[SMC_LINKS_PER_LGR_MAX];
156 					/* mem region registered */
157 			u8		is_map_ib[SMC_LINKS_PER_LGR_MAX];
158 					/* mem region mapped to lnk */
159 			u8		is_reg_err;
160 					/* buffer registration err */
161 		};
162 		struct { /* SMC-D */
163 			unsigned short	sba_idx;
164 					/* SBA index number */
165 			u64		token;
166 					/* DMB token number */
167 			dma_addr_t	dma_addr;
168 					/* DMA address */
169 		};
170 	};
171 };
172 
173 struct smc_rtoken {				/* address/key of remote RMB */
174 	u64			dma_addr;
175 	u32			rkey;
176 };
177 
178 #define SMC_LGR_ID_SIZE		4
179 #define SMC_BUF_MIN_SIZE	16384	/* minimum size of an RMB */
180 #define SMC_RMBE_SIZES		16	/* number of distinct RMBE sizes */
181 /* theoretically, the RFC states that largest size would be 512K,
182  * i.e. compressed 5 and thus 6 sizes (0..5), despite
183  * struct smc_clc_msg_accept_confirm.rmbe_size being a 4 bit value (0..15)
184  */
185 
186 struct smcd_dev;
187 
188 enum smc_lgr_type {				/* redundancy state of lgr */
189 	SMC_LGR_NONE,			/* no active links, lgr to be deleted */
190 	SMC_LGR_SINGLE,			/* 1 active RNIC on each peer */
191 	SMC_LGR_SYMMETRIC,		/* 2 active RNICs on each peer */
192 	SMC_LGR_ASYMMETRIC_PEER,	/* local has 2, peer 1 active RNICs */
193 	SMC_LGR_ASYMMETRIC_LOCAL,	/* local has 1, peer 2 active RNICs */
194 };
195 
196 enum smc_llc_flowtype {
197 	SMC_LLC_FLOW_NONE	= 0,
198 	SMC_LLC_FLOW_ADD_LINK	= 2,
199 	SMC_LLC_FLOW_DEL_LINK	= 4,
200 	SMC_LLC_FLOW_RKEY	= 6,
201 };
202 
203 struct smc_llc_qentry;
204 
205 struct smc_llc_flow {
206 	enum smc_llc_flowtype type;
207 	struct smc_llc_qentry *qentry;
208 };
209 
210 struct smc_link_group {
211 	struct list_head	list;
212 	struct rb_root		conns_all;	/* connection tree */
213 	rwlock_t		conns_lock;	/* protects conns_all */
214 	unsigned int		conns_num;	/* current # of connections */
215 	unsigned short		vlan_id;	/* vlan id of link group */
216 
217 	struct list_head	sndbufs[SMC_RMBE_SIZES];/* tx buffers */
218 	struct mutex		sndbufs_lock;	/* protects tx buffers */
219 	struct list_head	rmbs[SMC_RMBE_SIZES];	/* rx buffers */
220 	struct mutex		rmbs_lock;	/* protects rx buffers */
221 
222 	u8			id[SMC_LGR_ID_SIZE];	/* unique lgr id */
223 	struct delayed_work	free_work;	/* delayed freeing of an lgr */
224 	struct work_struct	terminate_work;	/* abnormal lgr termination */
225 	u8			sync_err : 1;	/* lgr no longer fits to peer */
226 	u8			terminating : 1;/* lgr is terminating */
227 	u8			freefast : 1;	/* free worker scheduled fast */
228 	u8			freeing : 1;	/* lgr is being freed */
229 
230 	bool			is_smcd;	/* SMC-R or SMC-D */
231 	union {
232 		struct { /* SMC-R */
233 			enum smc_lgr_role	role;
234 						/* client or server */
235 			struct smc_link		lnk[SMC_LINKS_PER_LGR_MAX];
236 						/* smc link */
237 			char			peer_systemid[SMC_SYSTEMID_LEN];
238 						/* unique system_id of peer */
239 			struct smc_rtoken	rtokens[SMC_RMBS_PER_LGR_MAX]
240 						[SMC_LINKS_PER_LGR_MAX];
241 						/* remote addr/key pairs */
242 			DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
243 						/* used rtoken elements */
244 			u8			next_link_id;
245 			enum smc_lgr_type	type;
246 						/* redundancy state */
247 			struct list_head	llc_event_q;
248 						/* queue for llc events */
249 			spinlock_t		llc_event_q_lock;
250 						/* protects llc_event_q */
251 			struct work_struct	llc_event_work;
252 						/* llc event worker */
253 			wait_queue_head_t	llc_waiter;
254 						/* w4 next llc event */
255 			struct smc_llc_flow	llc_flow_lcl;
256 						/* llc local control field */
257 			struct smc_llc_flow	llc_flow_rmt;
258 						/* llc remote control field */
259 			struct smc_llc_qentry	*delayed_event;
260 						/* arrived when flow active */
261 			spinlock_t		llc_flow_lock;
262 						/* protects llc flow */
263 			int			llc_testlink_time;
264 						/* link keep alive time */
265 		};
266 		struct { /* SMC-D */
267 			u64			peer_gid;
268 						/* Peer GID (remote) */
269 			struct smcd_dev		*smcd;
270 						/* ISM device for VLAN reg. */
271 			u8			peer_shutdown : 1;
272 						/* peer triggered shutdownn */
273 		};
274 	};
275 };
276 
277 struct smc_clc_msg_local;
278 
279 struct smc_init_info {
280 	u8			is_smcd;
281 	unsigned short		vlan_id;
282 	int			srv_first_contact;
283 	int			cln_first_contact;
284 	/* SMC-R */
285 	struct smc_clc_msg_local *ib_lcl;
286 	struct smc_ib_device	*ib_dev;
287 	u8			ib_gid[SMC_GID_SIZE];
288 	u8			ib_port;
289 	u32			ib_clcqpn;
290 	/* SMC-D */
291 	u64			ism_gid;
292 	struct smcd_dev		*ism_dev;
293 };
294 
295 /* Find the connection associated with the given alert token in the link group.
296  * To use rbtrees we have to implement our own search core.
297  * Requires @conns_lock
298  * @token	alert token to search for
299  * @lgr		 link group to search in
300  * Returns connection associated with token if found, NULL otherwise.
301  */
302 static inline struct smc_connection *smc_lgr_find_conn(
303 	u32 token, struct smc_link_group *lgr)
304 {
305 	struct smc_connection *res = NULL;
306 	struct rb_node *node;
307 
308 	node = lgr->conns_all.rb_node;
309 	while (node) {
310 		struct smc_connection *cur = rb_entry(node,
311 					struct smc_connection, alert_node);
312 
313 		if (cur->alert_token_local > token) {
314 			node = node->rb_left;
315 		} else {
316 			if (cur->alert_token_local < token) {
317 				node = node->rb_right;
318 			} else {
319 				res = cur;
320 				break;
321 			}
322 		}
323 	}
324 
325 	return res;
326 }
327 
328 /* returns true if the specified link is usable */
329 static inline bool smc_link_usable(struct smc_link *lnk)
330 {
331 	if (lnk->state == SMC_LNK_UNUSED || lnk->state == SMC_LNK_INACTIVE)
332 		return false;
333 	return true;
334 }
335 
336 struct smc_sock;
337 struct smc_clc_msg_accept_confirm;
338 struct smc_clc_msg_local;
339 
340 void smc_lgr_forget(struct smc_link_group *lgr);
341 void smc_lgr_cleanup_early(struct smc_connection *conn);
342 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
343 void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport);
344 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
345 			unsigned short vlan);
346 void smc_smcd_terminate_all(struct smcd_dev *dev);
347 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
348 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
349 int smc_uncompress_bufsize(u8 compressed);
350 int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_link *link,
351 			    struct smc_clc_msg_accept_confirm *clc);
352 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey);
353 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey);
354 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
355 		    __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey);
356 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
357 		     __be64 nw_vaddr, __be32 nw_rkey);
358 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
359 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
360 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
361 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
362 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini);
363 
364 void smc_conn_free(struct smc_connection *conn);
365 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini);
366 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr);
367 int smc_core_init(void);
368 void smc_core_exit(void);
369 
370 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
371 {
372 	return link->lgr;
373 }
374 #endif
375