GNU Linux-libre 5.10.153-gnu1
[releases.git] / net / smc / smc_core.h
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 #define SMC_LGR_ID_SIZE         4
74
75 struct smc_link {
76         struct smc_ib_device    *smcibdev;      /* ib-device */
77         u8                      ibport;         /* port - values 1 | 2 */
78         struct ib_pd            *roce_pd;       /* IB protection domain,
79                                                  * unique for every RoCE QP
80                                                  */
81         struct ib_qp            *roce_qp;       /* IB queue pair */
82         struct ib_qp_attr       qp_attr;        /* IB queue pair attributes */
83
84         struct smc_wr_buf       *wr_tx_bufs;    /* WR send payload buffers */
85         struct ib_send_wr       *wr_tx_ibs;     /* WR send meta data */
86         struct ib_sge           *wr_tx_sges;    /* WR send gather meta data */
87         struct smc_rdma_sges    *wr_tx_rdma_sges;/*RDMA WRITE gather meta data*/
88         struct smc_rdma_wr      *wr_tx_rdmas;   /* WR RDMA WRITE */
89         struct smc_wr_tx_pend   *wr_tx_pends;   /* WR send waiting for CQE */
90         struct completion       *wr_tx_compl;   /* WR send CQE completion */
91         /* above four vectors have wr_tx_cnt elements and use the same index */
92         dma_addr_t              wr_tx_dma_addr; /* DMA address of wr_tx_bufs */
93         atomic_long_t           wr_tx_id;       /* seq # of last sent WR */
94         unsigned long           *wr_tx_mask;    /* bit mask of used indexes */
95         u32                     wr_tx_cnt;      /* number of WR send buffers */
96         wait_queue_head_t       wr_tx_wait;     /* wait for free WR send buf */
97         atomic_t                wr_tx_refcnt;   /* tx refs to link */
98
99         struct smc_wr_buf       *wr_rx_bufs;    /* WR recv payload buffers */
100         struct ib_recv_wr       *wr_rx_ibs;     /* WR recv meta data */
101         struct ib_sge           *wr_rx_sges;    /* WR recv scatter meta data */
102         /* above three vectors have wr_rx_cnt elements and use the same index */
103         dma_addr_t              wr_rx_dma_addr; /* DMA address of wr_rx_bufs */
104         u64                     wr_rx_id;       /* seq # of last recv WR */
105         u32                     wr_rx_cnt;      /* number of WR recv buffers */
106         unsigned long           wr_rx_tstamp;   /* jiffies when last buf rx */
107
108         struct ib_reg_wr        wr_reg;         /* WR register memory region */
109         wait_queue_head_t       wr_reg_wait;    /* wait for wr_reg result */
110         atomic_t                wr_reg_refcnt;  /* reg refs to link */
111         enum smc_wr_reg_state   wr_reg_state;   /* state of wr_reg request */
112
113         u8                      gid[SMC_GID_SIZE];/* gid matching used vlan id*/
114         u8                      sgid_index;     /* gid index for vlan id      */
115         u32                     peer_qpn;       /* QP number of peer */
116         enum ib_mtu             path_mtu;       /* used mtu */
117         enum ib_mtu             peer_mtu;       /* mtu size of peer */
118         u32                     psn_initial;    /* QP tx initial packet seqno */
119         u32                     peer_psn;       /* QP rx initial packet seqno */
120         u8                      peer_mac[ETH_ALEN];     /* = gid[8:10||13:15] */
121         u8                      peer_gid[SMC_GID_SIZE]; /* gid of peer*/
122         u8                      link_id;        /* unique # within link group */
123         u8                      link_uid[SMC_LGR_ID_SIZE]; /* unique lnk id */
124         u8                      peer_link_uid[SMC_LGR_ID_SIZE]; /* peer uid */
125         u8                      link_idx;       /* index in lgr link array */
126         u8                      link_is_asym;   /* is link asymmetric? */
127         struct smc_link_group   *lgr;           /* parent link group */
128         struct work_struct      link_down_wrk;  /* wrk to bring link down */
129
130         enum smc_link_state     state;          /* state of link */
131         struct delayed_work     llc_testlink_wrk; /* testlink worker */
132         struct completion       llc_testlink_resp; /* wait for rx of testlink */
133         int                     llc_testlink_time; /* testlink interval */
134 };
135
136 /* For now we just allow one parallel link per link group. The SMC protocol
137  * allows more (up to 8).
138  */
139 #define SMC_LINKS_PER_LGR_MAX   3
140 #define SMC_SINGLE_LINK         0
141
142 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
143 struct smc_buf_desc {
144         struct list_head        list;
145         void                    *cpu_addr;      /* virtual address of buffer */
146         struct page             *pages;
147         int                     len;            /* length of buffer */
148         u32                     used;           /* currently used / unused */
149         union {
150                 struct { /* SMC-R */
151                         struct sg_table sgt[SMC_LINKS_PER_LGR_MAX];
152                                         /* virtual buffer */
153                         struct ib_mr    *mr_rx[SMC_LINKS_PER_LGR_MAX];
154                                         /* for rmb only: memory region
155                                          * incl. rkey provided to peer
156                                          */
157                         u32             order;  /* allocation order */
158
159                         u8              is_conf_rkey;
160                                         /* confirm_rkey done */
161                         u8              is_reg_mr[SMC_LINKS_PER_LGR_MAX];
162                                         /* mem region registered */
163                         u8              is_map_ib[SMC_LINKS_PER_LGR_MAX];
164                                         /* mem region mapped to lnk */
165                         u8              is_reg_err;
166                                         /* buffer registration err */
167                 };
168                 struct { /* SMC-D */
169                         unsigned short  sba_idx;
170                                         /* SBA index number */
171                         u64             token;
172                                         /* DMB token number */
173                         dma_addr_t      dma_addr;
174                                         /* DMA address */
175                 };
176         };
177 };
178
179 struct smc_rtoken {                             /* address/key of remote RMB */
180         u64                     dma_addr;
181         u32                     rkey;
182 };
183
184 #define SMC_BUF_MIN_SIZE        16384   /* minimum size of an RMB */
185 #define SMC_RMBE_SIZES          16      /* number of distinct RMBE sizes */
186 /* theoretically, the RFC states that largest size would be 512K,
187  * i.e. compressed 5 and thus 6 sizes (0..5), despite
188  * struct smc_clc_msg_accept_confirm.rmbe_size being a 4 bit value (0..15)
189  */
190
191 struct smcd_dev;
192
193 enum smc_lgr_type {                             /* redundancy state of lgr */
194         SMC_LGR_NONE,                   /* no active links, lgr to be deleted */
195         SMC_LGR_SINGLE,                 /* 1 active RNIC on each peer */
196         SMC_LGR_SYMMETRIC,              /* 2 active RNICs on each peer */
197         SMC_LGR_ASYMMETRIC_PEER,        /* local has 2, peer 1 active RNICs */
198         SMC_LGR_ASYMMETRIC_LOCAL,       /* local has 1, peer 2 active RNICs */
199 };
200
201 enum smc_llc_flowtype {
202         SMC_LLC_FLOW_NONE       = 0,
203         SMC_LLC_FLOW_ADD_LINK   = 2,
204         SMC_LLC_FLOW_DEL_LINK   = 4,
205         SMC_LLC_FLOW_RKEY       = 6,
206 };
207
208 struct smc_llc_qentry;
209
210 struct smc_llc_flow {
211         enum smc_llc_flowtype type;
212         struct smc_llc_qentry *qentry;
213 };
214
215 struct smc_link_group {
216         struct list_head        list;
217         struct rb_root          conns_all;      /* connection tree */
218         rwlock_t                conns_lock;     /* protects conns_all */
219         unsigned int            conns_num;      /* current # of connections */
220         unsigned short          vlan_id;        /* vlan id of link group */
221
222         struct list_head        sndbufs[SMC_RMBE_SIZES];/* tx buffers */
223         struct mutex            sndbufs_lock;   /* protects tx buffers */
224         struct list_head        rmbs[SMC_RMBE_SIZES];   /* rx buffers */
225         struct mutex            rmbs_lock;      /* protects rx buffers */
226
227         u8                      id[SMC_LGR_ID_SIZE];    /* unique lgr id */
228         struct delayed_work     free_work;      /* delayed freeing of an lgr */
229         struct work_struct      terminate_work; /* abnormal lgr termination */
230         struct workqueue_struct *tx_wq;         /* wq for conn. tx workers */
231         u8                      sync_err : 1;   /* lgr no longer fits to peer */
232         u8                      terminating : 1;/* lgr is terminating */
233         u8                      freeing : 1;    /* lgr is being freed */
234
235         bool                    is_smcd;        /* SMC-R or SMC-D */
236         u8                      smc_version;
237         u8                      negotiated_eid[SMC_MAX_EID_LEN];
238         u8                      peer_os;        /* peer operating system */
239         u8                      peer_smc_release;
240         u8                      peer_hostname[SMC_MAX_HOSTNAME_LEN];
241         union {
242                 struct { /* SMC-R */
243                         enum smc_lgr_role       role;
244                                                 /* client or server */
245                         struct smc_link         lnk[SMC_LINKS_PER_LGR_MAX];
246                                                 /* smc link */
247                         char                    peer_systemid[SMC_SYSTEMID_LEN];
248                                                 /* unique system_id of peer */
249                         struct smc_rtoken       rtokens[SMC_RMBS_PER_LGR_MAX]
250                                                 [SMC_LINKS_PER_LGR_MAX];
251                                                 /* remote addr/key pairs */
252                         DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
253                                                 /* used rtoken elements */
254                         u8                      next_link_id;
255                         enum smc_lgr_type       type;
256                                                 /* redundancy state */
257                         u8                      pnet_id[SMC_MAX_PNETID_LEN + 1];
258                                                 /* pnet id of this lgr */
259                         struct list_head        llc_event_q;
260                                                 /* queue for llc events */
261                         spinlock_t              llc_event_q_lock;
262                                                 /* protects llc_event_q */
263                         struct mutex            llc_conf_mutex;
264                                                 /* protects lgr reconfig. */
265                         struct work_struct      llc_add_link_work;
266                         struct work_struct      llc_del_link_work;
267                         struct work_struct      llc_event_work;
268                                                 /* llc event worker */
269                         wait_queue_head_t       llc_flow_waiter;
270                                                 /* w4 next llc event */
271                         wait_queue_head_t       llc_msg_waiter;
272                                                 /* w4 next llc msg */
273                         struct smc_llc_flow     llc_flow_lcl;
274                                                 /* llc local control field */
275                         struct smc_llc_flow     llc_flow_rmt;
276                                                 /* llc remote control field */
277                         struct smc_llc_qentry   *delayed_event;
278                                                 /* arrived when flow active */
279                         spinlock_t              llc_flow_lock;
280                                                 /* protects llc flow */
281                         int                     llc_testlink_time;
282                                                 /* link keep alive time */
283                         u32                     llc_termination_rsn;
284                                                 /* rsn code for termination */
285                 };
286                 struct { /* SMC-D */
287                         u64                     peer_gid;
288                                                 /* Peer GID (remote) */
289                         struct smcd_dev         *smcd;
290                                                 /* ISM device for VLAN reg. */
291                         u8                      peer_shutdown : 1;
292                                                 /* peer triggered shutdownn */
293                 };
294         };
295 };
296
297 struct smc_clc_msg_local;
298
299 struct smc_init_info {
300         u8                      is_smcd;
301         u8                      smc_type_v1;
302         u8                      smc_type_v2;
303         u8                      first_contact_peer;
304         u8                      first_contact_local;
305         unsigned short          vlan_id;
306         /* SMC-R */
307         struct smc_clc_msg_local *ib_lcl;
308         struct smc_ib_device    *ib_dev;
309         u8                      ib_gid[SMC_GID_SIZE];
310         u8                      ib_port;
311         u32                     ib_clcqpn;
312         /* SMC-D */
313         u64                     ism_peer_gid[SMC_MAX_ISM_DEVS + 1];
314         struct smcd_dev         *ism_dev[SMC_MAX_ISM_DEVS + 1];
315         u16                     ism_chid[SMC_MAX_ISM_DEVS + 1];
316         u8                      ism_offered_cnt; /* # of ISM devices offered */
317         u8                      ism_selected;    /* index of selected ISM dev*/
318         u8                      smcd_version;
319 };
320
321 /* Find the connection associated with the given alert token in the link group.
322  * To use rbtrees we have to implement our own search core.
323  * Requires @conns_lock
324  * @token       alert token to search for
325  * @lgr          link group to search in
326  * Returns connection associated with token if found, NULL otherwise.
327  */
328 static inline struct smc_connection *smc_lgr_find_conn(
329         u32 token, struct smc_link_group *lgr)
330 {
331         struct smc_connection *res = NULL;
332         struct rb_node *node;
333
334         node = lgr->conns_all.rb_node;
335         while (node) {
336                 struct smc_connection *cur = rb_entry(node,
337                                         struct smc_connection, alert_node);
338
339                 if (cur->alert_token_local > token) {
340                         node = node->rb_left;
341                 } else {
342                         if (cur->alert_token_local < token) {
343                                 node = node->rb_right;
344                         } else {
345                                 res = cur;
346                                 break;
347                         }
348                 }
349         }
350
351         return res;
352 }
353
354 /* returns true if the specified link is usable */
355 static inline bool smc_link_usable(struct smc_link *lnk)
356 {
357         if (lnk->state == SMC_LNK_UNUSED || lnk->state == SMC_LNK_INACTIVE)
358                 return false;
359         return true;
360 }
361
362 static inline bool smc_link_sendable(struct smc_link *lnk)
363 {
364         return smc_link_usable(lnk) &&
365                 lnk->qp_attr.cur_qp_state == IB_QPS_RTS;
366 }
367
368 static inline bool smc_link_active(struct smc_link *lnk)
369 {
370         return lnk->state == SMC_LNK_ACTIVE;
371 }
372
373 struct smc_sock;
374 struct smc_clc_msg_accept_confirm;
375 struct smc_clc_msg_local;
376
377 void smc_lgr_cleanup_early(struct smc_connection *conn);
378 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
379 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
380 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport);
381 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
382                         unsigned short vlan);
383 void smc_smcd_terminate_all(struct smcd_dev *dev);
384 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
385 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
386 int smc_uncompress_bufsize(u8 compressed);
387 int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_link *link,
388                             struct smc_clc_msg_accept_confirm *clc);
389 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey);
390 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey);
391 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
392                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey);
393 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
394                      __be64 nw_vaddr, __be32 nw_rkey);
395 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
396 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
397 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
398 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
399 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini);
400
401 void smc_conn_free(struct smc_connection *conn);
402 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini);
403 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr);
404 int smc_core_init(void);
405 void smc_core_exit(void);
406
407 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
408                    u8 link_idx, struct smc_init_info *ini);
409 void smcr_link_clear(struct smc_link *lnk, bool log);
410 int smcr_buf_map_lgr(struct smc_link *lnk);
411 int smcr_buf_reg_lgr(struct smc_link *lnk);
412 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type);
413 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
414                             enum smc_lgr_type new_type, int asym_lnk_idx);
415 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc);
416 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
417                                   struct smc_link *from_lnk, bool is_dev_err);
418 void smcr_link_down_cond(struct smc_link *lnk);
419 void smcr_link_down_cond_sched(struct smc_link *lnk);
420
421 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
422 {
423         return link->lgr;
424 }
425 #endif