d70da797f49537c892cbfaaa3aabfea1d69950a4
[linux-2.6-microblaze.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
98         struct smc_wr_buf       *wr_rx_bufs;    /* WR recv payload buffers */
99         struct ib_recv_wr       *wr_rx_ibs;     /* WR recv meta data */
100         struct ib_sge           *wr_rx_sges;    /* WR recv scatter meta data */
101         /* above three vectors have wr_rx_cnt elements and use the same index */
102         dma_addr_t              wr_rx_dma_addr; /* DMA address of wr_rx_bufs */
103         u64                     wr_rx_id;       /* seq # of last recv WR */
104         u32                     wr_rx_cnt;      /* number of WR recv buffers */
105         unsigned long           wr_rx_tstamp;   /* jiffies when last buf rx */
106
107         struct ib_reg_wr        wr_reg;         /* WR register memory region */
108         wait_queue_head_t       wr_reg_wait;    /* wait for wr_reg result */
109         enum smc_wr_reg_state   wr_reg_state;   /* state of wr_reg request */
110
111         u8                      gid[SMC_GID_SIZE];/* gid matching used vlan id*/
112         u8                      sgid_index;     /* gid index for vlan id      */
113         u32                     peer_qpn;       /* QP number of peer */
114         enum ib_mtu             path_mtu;       /* used mtu */
115         enum ib_mtu             peer_mtu;       /* mtu size of peer */
116         u32                     psn_initial;    /* QP tx initial packet seqno */
117         u32                     peer_psn;       /* QP rx initial packet seqno */
118         u8                      peer_mac[ETH_ALEN];     /* = gid[8:10||13:15] */
119         u8                      peer_gid[SMC_GID_SIZE]; /* gid of peer*/
120         u8                      link_id;        /* unique # within link group */
121         u8                      link_uid[SMC_LGR_ID_SIZE]; /* unique lnk id */
122         u8                      peer_link_uid[SMC_LGR_ID_SIZE]; /* peer uid */
123         u8                      link_idx;       /* index in lgr link array */
124         u8                      link_is_asym;   /* is link asymmetric? */
125         struct smc_link_group   *lgr;           /* parent link group */
126         struct work_struct      link_down_wrk;  /* wrk to bring link down */
127
128         enum smc_link_state     state;          /* state of link */
129         struct delayed_work     llc_testlink_wrk; /* testlink worker */
130         struct completion       llc_testlink_resp; /* wait for rx of testlink */
131         int                     llc_testlink_time; /* testlink interval */
132 };
133
134 /* For now we just allow one parallel link per link group. The SMC protocol
135  * allows more (up to 8).
136  */
137 #define SMC_LINKS_PER_LGR_MAX   3
138 #define SMC_SINGLE_LINK         0
139
140 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
141 struct smc_buf_desc {
142         struct list_head        list;
143         void                    *cpu_addr;      /* virtual address of buffer */
144         struct page             *pages;
145         int                     len;            /* length of buffer */
146         u32                     used;           /* currently used / unused */
147         union {
148                 struct { /* SMC-R */
149                         struct sg_table sgt[SMC_LINKS_PER_LGR_MAX];
150                                         /* virtual buffer */
151                         struct ib_mr    *mr_rx[SMC_LINKS_PER_LGR_MAX];
152                                         /* for rmb only: memory region
153                                          * incl. rkey provided to peer
154                                          */
155                         u32             order;  /* allocation order */
156
157                         u8              is_conf_rkey;
158                                         /* confirm_rkey done */
159                         u8              is_reg_mr[SMC_LINKS_PER_LGR_MAX];
160                                         /* mem region registered */
161                         u8              is_map_ib[SMC_LINKS_PER_LGR_MAX];
162                                         /* mem region mapped to lnk */
163                         u8              is_reg_err;
164                                         /* buffer registration err */
165                 };
166                 struct { /* SMC-D */
167                         unsigned short  sba_idx;
168                                         /* SBA index number */
169                         u64             token;
170                                         /* DMB token number */
171                         dma_addr_t      dma_addr;
172                                         /* DMA address */
173                 };
174         };
175 };
176
177 struct smc_rtoken {                             /* address/key of remote RMB */
178         u64                     dma_addr;
179         u32                     rkey;
180 };
181
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 enum smc_lgr_type {                             /* redundancy state of lgr */
192         SMC_LGR_NONE,                   /* no active links, lgr to be deleted */
193         SMC_LGR_SINGLE,                 /* 1 active RNIC on each peer */
194         SMC_LGR_SYMMETRIC,              /* 2 active RNICs on each peer */
195         SMC_LGR_ASYMMETRIC_PEER,        /* local has 2, peer 1 active RNICs */
196         SMC_LGR_ASYMMETRIC_LOCAL,       /* local has 1, peer 2 active RNICs */
197 };
198
199 enum smc_llc_flowtype {
200         SMC_LLC_FLOW_NONE       = 0,
201         SMC_LLC_FLOW_ADD_LINK   = 2,
202         SMC_LLC_FLOW_DEL_LINK   = 4,
203         SMC_LLC_FLOW_RKEY       = 6,
204 };
205
206 struct smc_llc_qentry;
207
208 struct smc_llc_flow {
209         enum smc_llc_flowtype type;
210         struct smc_llc_qentry *qentry;
211 };
212
213 struct smc_link_group {
214         struct list_head        list;
215         struct rb_root          conns_all;      /* connection tree */
216         rwlock_t                conns_lock;     /* protects conns_all */
217         unsigned int            conns_num;      /* current # of connections */
218         unsigned short          vlan_id;        /* vlan id of link group */
219
220         struct list_head        sndbufs[SMC_RMBE_SIZES];/* tx buffers */
221         struct mutex            sndbufs_lock;   /* protects tx buffers */
222         struct list_head        rmbs[SMC_RMBE_SIZES];   /* rx buffers */
223         struct mutex            rmbs_lock;      /* protects rx buffers */
224
225         u8                      id[SMC_LGR_ID_SIZE];    /* unique lgr id */
226         struct delayed_work     free_work;      /* delayed freeing of an lgr */
227         struct work_struct      terminate_work; /* abnormal lgr termination */
228         u8                      sync_err : 1;   /* lgr no longer fits to peer */
229         u8                      terminating : 1;/* lgr is terminating */
230         u8                      freefast : 1;   /* free worker scheduled fast */
231         u8                      freeing : 1;    /* lgr is being freed */
232
233         bool                    is_smcd;        /* SMC-R or SMC-D */
234         union {
235                 struct { /* SMC-R */
236                         enum smc_lgr_role       role;
237                                                 /* client or server */
238                         struct smc_link         lnk[SMC_LINKS_PER_LGR_MAX];
239                                                 /* smc link */
240                         char                    peer_systemid[SMC_SYSTEMID_LEN];
241                                                 /* unique system_id of peer */
242                         struct smc_rtoken       rtokens[SMC_RMBS_PER_LGR_MAX]
243                                                 [SMC_LINKS_PER_LGR_MAX];
244                                                 /* remote addr/key pairs */
245                         DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
246                                                 /* used rtoken elements */
247                         u8                      next_link_id;
248                         enum smc_lgr_type       type;
249                                                 /* redundancy state */
250                         u8                      pnet_id[SMC_MAX_PNETID_LEN + 1];
251                                                 /* pnet id of this lgr */
252                         struct list_head        llc_event_q;
253                                                 /* queue for llc events */
254                         spinlock_t              llc_event_q_lock;
255                                                 /* protects llc_event_q */
256                         struct mutex            llc_conf_mutex;
257                                                 /* protects lgr reconfig. */
258                         struct work_struct      llc_add_link_work;
259                         struct work_struct      llc_del_link_work;
260                         struct work_struct      llc_event_work;
261                                                 /* llc event worker */
262                         wait_queue_head_t       llc_flow_waiter;
263                                                 /* w4 next llc event */
264                         wait_queue_head_t       llc_msg_waiter;
265                                                 /* w4 next llc msg */
266                         struct smc_llc_flow     llc_flow_lcl;
267                                                 /* llc local control field */
268                         struct smc_llc_flow     llc_flow_rmt;
269                                                 /* llc remote control field */
270                         struct smc_llc_qentry   *delayed_event;
271                                                 /* arrived when flow active */
272                         spinlock_t              llc_flow_lock;
273                                                 /* protects llc flow */
274                         int                     llc_testlink_time;
275                                                 /* link keep alive time */
276                         u32                     llc_termination_rsn;
277                                                 /* rsn code for termination */
278                 };
279                 struct { /* SMC-D */
280                         u64                     peer_gid;
281                                                 /* Peer GID (remote) */
282                         struct smcd_dev         *smcd;
283                                                 /* ISM device for VLAN reg. */
284                         u8                      peer_shutdown : 1;
285                                                 /* peer triggered shutdownn */
286                 };
287         };
288 };
289
290 struct smc_clc_msg_local;
291
292 struct smc_init_info {
293         u8                      is_smcd;
294         u8                      first_contact_peer;
295         u8                      first_contact_local;
296         unsigned short          vlan_id;
297         /* SMC-R */
298         struct smc_clc_msg_local *ib_lcl;
299         struct smc_ib_device    *ib_dev;
300         u8                      ib_gid[SMC_GID_SIZE];
301         u8                      ib_port;
302         u32                     ib_clcqpn;
303         /* SMC-D */
304         u64                     ism_peer_gid;
305         struct smcd_dev         *ism_dev;
306 };
307
308 /* Find the connection associated with the given alert token in the link group.
309  * To use rbtrees we have to implement our own search core.
310  * Requires @conns_lock
311  * @token       alert token to search for
312  * @lgr          link group to search in
313  * Returns connection associated with token if found, NULL otherwise.
314  */
315 static inline struct smc_connection *smc_lgr_find_conn(
316         u32 token, struct smc_link_group *lgr)
317 {
318         struct smc_connection *res = NULL;
319         struct rb_node *node;
320
321         node = lgr->conns_all.rb_node;
322         while (node) {
323                 struct smc_connection *cur = rb_entry(node,
324                                         struct smc_connection, alert_node);
325
326                 if (cur->alert_token_local > token) {
327                         node = node->rb_left;
328                 } else {
329                         if (cur->alert_token_local < token) {
330                                 node = node->rb_right;
331                         } else {
332                                 res = cur;
333                                 break;
334                         }
335                 }
336         }
337
338         return res;
339 }
340
341 /* returns true if the specified link is usable */
342 static inline bool smc_link_usable(struct smc_link *lnk)
343 {
344         if (lnk->state == SMC_LNK_UNUSED || lnk->state == SMC_LNK_INACTIVE)
345                 return false;
346         return true;
347 }
348
349 static inline bool smc_link_active(struct smc_link *lnk)
350 {
351         return lnk->state == SMC_LNK_ACTIVE;
352 }
353
354 struct smc_sock;
355 struct smc_clc_msg_accept_confirm;
356 struct smc_clc_msg_local;
357
358 void smc_lgr_cleanup_early(struct smc_connection *conn);
359 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
360 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
361 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport);
362 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
363                         unsigned short vlan);
364 void smc_smcd_terminate_all(struct smcd_dev *dev);
365 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
366 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
367 int smc_uncompress_bufsize(u8 compressed);
368 int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_link *link,
369                             struct smc_clc_msg_accept_confirm *clc);
370 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey);
371 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey);
372 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
373                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey);
374 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
375                      __be64 nw_vaddr, __be32 nw_rkey);
376 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
377 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
378 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
379 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
380 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini);
381
382 void smc_conn_free(struct smc_connection *conn);
383 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini);
384 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr);
385 int smc_core_init(void);
386 void smc_core_exit(void);
387
388 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
389                    u8 link_idx, struct smc_init_info *ini);
390 void smcr_link_clear(struct smc_link *lnk, bool log);
391 int smcr_buf_map_lgr(struct smc_link *lnk);
392 int smcr_buf_reg_lgr(struct smc_link *lnk);
393 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type);
394 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
395                             enum smc_lgr_type new_type, int asym_lnk_idx);
396 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc);
397 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
398                                   struct smc_link *from_lnk, bool is_dev_err);
399 void smcr_link_down_cond(struct smc_link *lnk);
400 void smcr_link_down_cond_sched(struct smc_link *lnk);
401
402 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
403 {
404         return link->lgr;
405 }
406 #endif