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_INACTIVE, /* link is inactive */
36 SMC_LNK_ACTIVATING, /* link is being activated */
37 SMC_LNK_ACTIVE, /* link is active */
38 SMC_LNK_DELETING, /* link is being deleted */
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
119 enum smc_link_state state; /* state of link */
120 struct workqueue_struct *llc_wq; /* single thread work queue */
121 struct completion llc_confirm; /* wait for rx of conf link */
122 struct completion llc_confirm_resp; /* wait 4 rx of cnf lnk rsp */
123 int llc_confirm_rc; /* rc from confirm link msg */
124 int llc_confirm_resp_rc; /* rc from conf_resp msg */
125 struct completion llc_add; /* wait for rx of add link */
126 struct completion llc_add_resp; /* wait for rx of add link rsp*/
127 struct delayed_work llc_testlink_wrk; /* testlink worker */
128 struct completion llc_testlink_resp; /* wait for rx of testlink */
129 int llc_testlink_time; /* testlink interval */
130 struct completion llc_confirm_rkey; /* wait 4 rx of cnf rkey */
131 int llc_confirm_rkey_rc; /* rc from cnf rkey msg */
132 struct completion llc_delete_rkey; /* wait 4 rx of del rkey */
133 int llc_delete_rkey_rc; /* rc from del rkey msg */
134 struct mutex llc_delete_rkey_mutex; /* serialize usage */
135 };
136
137 /* For now we just allow one parallel link per link group. The SMC protocol
138 * allows more (up to 8).
139 */
140 #define SMC_LINKS_PER_LGR_MAX 1
141 #define SMC_SINGLE_LINK 0
142
143 #define SMC_FIRST_CONTACT 1 /* first contact to a peer */
144 #define SMC_REUSE_CONTACT 0 /* follow-on contact to a peer*/
145
146 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
147 struct smc_buf_desc {
148 struct list_head list;
149 void *cpu_addr; /* virtual address of buffer */
150 struct page *pages;
151 int len; /* length of buffer */
152 u32 used; /* currently used / unused */
153 u8 wr_reg : 1; /* mem region registered */
154 u8 regerr : 1; /* err during registration */
155 union {
156 struct { /* SMC-R */
157 struct sg_table sgt[SMC_LINKS_PER_LGR_MAX];
158 /* virtual buffer */
159 struct ib_mr *mr_rx[SMC_LINKS_PER_LGR_MAX];
160 /* for rmb only: memory region
161 * incl. rkey provided to peer
162 */
163 u32 order; /* allocation order */
164 };
165 struct { /* SMC-D */
166 unsigned short sba_idx;
167 /* SBA index number */
168 u64 token;
169 /* DMB token number */
170 dma_addr_t dma_addr;
171 /* DMA address */
172 };
173 };
174 };
175
176 struct smc_rtoken { /* address/key of remote RMB */
177 u64 dma_addr;
178 u32 rkey;
179 };
180
181 #define SMC_LGR_ID_SIZE 4
182 #define SMC_BUF_MIN_SIZE 16384 /* minimum size of an RMB */
183 #define SMC_RMBE_SIZES 16 /* number of distinct RMBE sizes */
184 /* theoretically, the RFC states that largest size would be 512K,
185 * i.e. compressed 5 and thus 6 sizes (0..5), despite
186 * struct smc_clc_msg_accept_confirm.rmbe_size being a 4 bit value (0..15)
187 */
188
189 struct smcd_dev;
190
191 struct smc_link_group {
192 struct list_head list;
193 struct rb_root conns_all; /* connection tree */
194 rwlock_t conns_lock; /* protects conns_all */
195 unsigned int conns_num; /* current # of connections */
196 unsigned short vlan_id; /* vlan id of link group */
197
198 struct list_head sndbufs[SMC_RMBE_SIZES];/* tx buffers */
199 rwlock_t sndbufs_lock; /* protects tx buffers */
200 struct list_head rmbs[SMC_RMBE_SIZES]; /* rx buffers */
201 rwlock_t rmbs_lock; /* protects rx buffers */
202
203 u8 id[SMC_LGR_ID_SIZE]; /* unique lgr id */
204 struct delayed_work free_work; /* delayed freeing of an lgr */
205 u8 sync_err : 1; /* lgr no longer fits to peer */
206 u8 terminating : 1;/* lgr is terminating */
207
208 bool is_smcd; /* SMC-R or SMC-D */
209 union {
210 struct { /* SMC-R */
211 enum smc_lgr_role role;
212 /* client or server */
213 struct smc_link lnk[SMC_LINKS_PER_LGR_MAX];
214 /* smc link */
215 char peer_systemid[SMC_SYSTEMID_LEN];
216 /* unique system_id of peer */
217 struct smc_rtoken rtokens[SMC_RMBS_PER_LGR_MAX]
218 [SMC_LINKS_PER_LGR_MAX];
219 /* remote addr/key pairs */
220 DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
221 /* used rtoken elements */
222 };
223 struct { /* SMC-D */
224 u64 peer_gid;
225 /* Peer GID (remote) */
226 struct smcd_dev *smcd;
227 /* ISM device for VLAN reg. */
228 };
229 };
230 };
231
232 struct smc_clc_msg_local;
233
234 struct smc_init_info {
235 u8 is_smcd;
236 unsigned short vlan_id;
237 int srv_first_contact;
238 int cln_first_contact;
239 /* SMC-R */
240 struct smc_clc_msg_local *ib_lcl;
241 struct smc_ib_device *ib_dev;
242 u8 ib_gid[SMC_GID_SIZE];
243 u8 ib_port;
244 u32 ib_clcqpn;
245 /* SMC-D */
246 u64 ism_gid;
247 struct smcd_dev *ism_dev;
248 };
249
250 /* Find the connection associated with the given alert token in the link group.
251 * To use rbtrees we have to implement our own search core.
252 * Requires @conns_lock
253 * @token alert token to search for
254 * @lgr link group to search in
255 * Returns connection associated with token if found, NULL otherwise.
256 */
257 static inline struct smc_connection *smc_lgr_find_conn(
258 u32 token, struct smc_link_group *lgr)
259 {
260 struct smc_connection *res = NULL;
261 struct rb_node *node;
262
263 node = lgr->conns_all.rb_node;
264 while (node) {
265 struct smc_connection *cur = rb_entry(node,
266 struct smc_connection, alert_node);
267
268 if (cur->alert_token_local > token) {
269 node = node->rb_left;
270 } else {
271 if (cur->alert_token_local < token) {
272 node = node->rb_right;
273 } else {
274 res = cur;
275 break;
276 }
277 }
278 }
279
280 return res;
281 }
282
283 struct smc_sock;
284 struct smc_clc_msg_accept_confirm;
285 struct smc_clc_msg_local;
286
287 void smc_lgr_forget(struct smc_link_group *lgr);
288 void smc_lgr_terminate(struct smc_link_group *lgr);
289 void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport);
290 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
291 unsigned short vlan);
292 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
293 int smc_uncompress_bufsize(u8 compressed);
294 int smc_rmb_rtoken_handling(struct smc_connection *conn,
295 struct smc_clc_msg_accept_confirm *clc);
296 int smc_rtoken_add(struct smc_link_group *lgr, __be64 nw_vaddr, __be32 nw_rkey);
297 int smc_rtoken_delete(struct smc_link_group *lgr, __be32 nw_rkey);
298 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
299 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
300 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
301 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
302 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini);
303
304 void smc_conn_free(struct smc_connection *conn);
305 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini);
306 void smcd_conn_free(struct smc_connection *conn);
307 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr);
308 void smc_core_exit(void);
309
310 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
311 {
312 return container_of(link, struct smc_link_group, lnk[SMC_SINGLE_LINK]);
313 }
314 #endif