net/smc: improved fix wait on already cleared link
[platform/kernel/linux-rpi.git] / net / smc / smc_core.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  Basic Transport Functions exploiting Infiniband API
6  *
7  *  Copyright IBM Corp. 2016
8  *
9  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
10  */
11
12 #include <linux/socket.h>
13 #include <linux/if_vlan.h>
14 #include <linux/random.h>
15 #include <linux/workqueue.h>
16 #include <linux/wait.h>
17 #include <linux/reboot.h>
18 #include <linux/mutex.h>
19 #include <linux/list.h>
20 #include <linux/smc.h>
21 #include <net/tcp.h>
22 #include <net/sock.h>
23 #include <rdma/ib_verbs.h>
24 #include <rdma/ib_cache.h>
25
26 #include "smc.h"
27 #include "smc_clc.h"
28 #include "smc_core.h"
29 #include "smc_ib.h"
30 #include "smc_wr.h"
31 #include "smc_llc.h"
32 #include "smc_cdc.h"
33 #include "smc_close.h"
34 #include "smc_ism.h"
35 #include "smc_netlink.h"
36 #include "smc_stats.h"
37
38 #define SMC_LGR_NUM_INCR                256
39 #define SMC_LGR_FREE_DELAY_SERV         (600 * HZ)
40 #define SMC_LGR_FREE_DELAY_CLNT         (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
41
42 struct smc_lgr_list smc_lgr_list = {    /* established link groups */
43         .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
44         .list = LIST_HEAD_INIT(smc_lgr_list.list),
45         .num = 0,
46 };
47
48 static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
49 static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
50
51 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
52                          struct smc_buf_desc *buf_desc);
53 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
54
55 static void smc_link_down_work(struct work_struct *work);
56
57 /* return head of link group list and its lock for a given link group */
58 static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
59                                                   spinlock_t **lgr_lock)
60 {
61         if (lgr->is_smcd) {
62                 *lgr_lock = &lgr->smcd->lgr_lock;
63                 return &lgr->smcd->lgr_list;
64         }
65
66         *lgr_lock = &smc_lgr_list.lock;
67         return &smc_lgr_list.list;
68 }
69
70 static void smc_ibdev_cnt_inc(struct smc_link *lnk)
71 {
72         atomic_inc(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
73 }
74
75 static void smc_ibdev_cnt_dec(struct smc_link *lnk)
76 {
77         atomic_dec(&lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
78 }
79
80 static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
81 {
82         /* client link group creation always follows the server link group
83          * creation. For client use a somewhat higher removal delay time,
84          * otherwise there is a risk of out-of-sync link groups.
85          */
86         if (!lgr->freeing) {
87                 mod_delayed_work(system_wq, &lgr->free_work,
88                                  (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
89                                                 SMC_LGR_FREE_DELAY_CLNT :
90                                                 SMC_LGR_FREE_DELAY_SERV);
91         }
92 }
93
94 /* Register connection's alert token in our lookup structure.
95  * To use rbtrees we have to implement our own insert core.
96  * Requires @conns_lock
97  * @smc         connection to register
98  * Returns 0 on success, != otherwise.
99  */
100 static void smc_lgr_add_alert_token(struct smc_connection *conn)
101 {
102         struct rb_node **link, *parent = NULL;
103         u32 token = conn->alert_token_local;
104
105         link = &conn->lgr->conns_all.rb_node;
106         while (*link) {
107                 struct smc_connection *cur = rb_entry(*link,
108                                         struct smc_connection, alert_node);
109
110                 parent = *link;
111                 if (cur->alert_token_local > token)
112                         link = &parent->rb_left;
113                 else
114                         link = &parent->rb_right;
115         }
116         /* Put the new node there */
117         rb_link_node(&conn->alert_node, parent, link);
118         rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
119 }
120
121 /* assign an SMC-R link to the connection */
122 static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
123 {
124         enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
125                                        SMC_LNK_ACTIVE;
126         int i, j;
127
128         /* do link balancing */
129         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
130                 struct smc_link *lnk = &conn->lgr->lnk[i];
131
132                 if (lnk->state != expected || lnk->link_is_asym)
133                         continue;
134                 if (conn->lgr->role == SMC_CLNT) {
135                         conn->lnk = lnk; /* temporary, SMC server assigns link*/
136                         break;
137                 }
138                 if (conn->lgr->conns_num % 2) {
139                         for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
140                                 struct smc_link *lnk2;
141
142                                 lnk2 = &conn->lgr->lnk[j];
143                                 if (lnk2->state == expected &&
144                                     !lnk2->link_is_asym) {
145                                         conn->lnk = lnk2;
146                                         break;
147                                 }
148                         }
149                 }
150                 if (!conn->lnk)
151                         conn->lnk = lnk;
152                 break;
153         }
154         if (!conn->lnk)
155                 return SMC_CLC_DECL_NOACTLINK;
156         atomic_inc(&conn->lnk->conn_cnt);
157         return 0;
158 }
159
160 /* Register connection in link group by assigning an alert token
161  * registered in a search tree.
162  * Requires @conns_lock
163  * Note that '0' is a reserved value and not assigned.
164  */
165 static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
166 {
167         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
168         static atomic_t nexttoken = ATOMIC_INIT(0);
169         int rc;
170
171         if (!conn->lgr->is_smcd) {
172                 rc = smcr_lgr_conn_assign_link(conn, first);
173                 if (rc)
174                         return rc;
175         }
176         /* find a new alert_token_local value not yet used by some connection
177          * in this link group
178          */
179         sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
180         while (!conn->alert_token_local) {
181                 conn->alert_token_local = atomic_inc_return(&nexttoken);
182                 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
183                         conn->alert_token_local = 0;
184         }
185         smc_lgr_add_alert_token(conn);
186         conn->lgr->conns_num++;
187         return 0;
188 }
189
190 /* Unregister connection and reset the alert token of the given connection<
191  */
192 static void __smc_lgr_unregister_conn(struct smc_connection *conn)
193 {
194         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
195         struct smc_link_group *lgr = conn->lgr;
196
197         rb_erase(&conn->alert_node, &lgr->conns_all);
198         if (conn->lnk)
199                 atomic_dec(&conn->lnk->conn_cnt);
200         lgr->conns_num--;
201         conn->alert_token_local = 0;
202         sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
203 }
204
205 /* Unregister connection from lgr
206  */
207 static void smc_lgr_unregister_conn(struct smc_connection *conn)
208 {
209         struct smc_link_group *lgr = conn->lgr;
210
211         if (!lgr)
212                 return;
213         write_lock_bh(&lgr->conns_lock);
214         if (conn->alert_token_local) {
215                 __smc_lgr_unregister_conn(conn);
216         }
217         write_unlock_bh(&lgr->conns_lock);
218         conn->lgr = NULL;
219 }
220
221 int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
222 {
223         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
224         char hostname[SMC_MAX_HOSTNAME_LEN + 1];
225         char smc_seid[SMC_MAX_EID_LEN + 1];
226         struct smcd_dev *smcd_dev;
227         struct nlattr *attrs;
228         u8 *seid = NULL;
229         u8 *host = NULL;
230         void *nlh;
231
232         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
233                           &smc_gen_nl_family, NLM_F_MULTI,
234                           SMC_NETLINK_GET_SYS_INFO);
235         if (!nlh)
236                 goto errmsg;
237         if (cb_ctx->pos[0])
238                 goto errout;
239         attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
240         if (!attrs)
241                 goto errout;
242         if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
243                 goto errattr;
244         if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
245                 goto errattr;
246         if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
247                 goto errattr;
248         smc_clc_get_hostname(&host);
249         if (host) {
250                 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
251                 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
252                 if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
253                         goto errattr;
254         }
255         mutex_lock(&smcd_dev_list.mutex);
256         smcd_dev = list_first_entry_or_null(&smcd_dev_list.list,
257                                             struct smcd_dev, list);
258         if (smcd_dev)
259                 smc_ism_get_system_eid(smcd_dev, &seid);
260         mutex_unlock(&smcd_dev_list.mutex);
261         if (seid && smc_ism_is_v2_capable()) {
262                 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
263                 smc_seid[SMC_MAX_EID_LEN] = 0;
264                 if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
265                         goto errattr;
266         }
267         nla_nest_end(skb, attrs);
268         genlmsg_end(skb, nlh);
269         cb_ctx->pos[0] = 1;
270         return skb->len;
271
272 errattr:
273         nla_nest_cancel(skb, attrs);
274 errout:
275         genlmsg_cancel(skb, nlh);
276 errmsg:
277         return skb->len;
278 }
279
280 static int smc_nl_fill_lgr(struct smc_link_group *lgr,
281                            struct sk_buff *skb,
282                            struct netlink_callback *cb)
283 {
284         char smc_target[SMC_MAX_PNETID_LEN + 1];
285         struct nlattr *attrs;
286
287         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCR);
288         if (!attrs)
289                 goto errout;
290
291         if (nla_put_u32(skb, SMC_NLA_LGR_R_ID, *((u32 *)&lgr->id)))
292                 goto errattr;
293         if (nla_put_u32(skb, SMC_NLA_LGR_R_CONNS_NUM, lgr->conns_num))
294                 goto errattr;
295         if (nla_put_u8(skb, SMC_NLA_LGR_R_ROLE, lgr->role))
296                 goto errattr;
297         if (nla_put_u8(skb, SMC_NLA_LGR_R_TYPE, lgr->type))
298                 goto errattr;
299         if (nla_put_u8(skb, SMC_NLA_LGR_R_VLAN_ID, lgr->vlan_id))
300                 goto errattr;
301         memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
302         smc_target[SMC_MAX_PNETID_LEN] = 0;
303         if (nla_put_string(skb, SMC_NLA_LGR_R_PNETID, smc_target))
304                 goto errattr;
305
306         nla_nest_end(skb, attrs);
307         return 0;
308 errattr:
309         nla_nest_cancel(skb, attrs);
310 errout:
311         return -EMSGSIZE;
312 }
313
314 static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
315                                 struct smc_link *link,
316                                 struct sk_buff *skb,
317                                 struct netlink_callback *cb)
318 {
319         char smc_ibname[IB_DEVICE_NAME_MAX];
320         u8 smc_gid_target[41];
321         struct nlattr *attrs;
322         u32 link_uid = 0;
323         void *nlh;
324
325         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
326                           &smc_gen_nl_family, NLM_F_MULTI,
327                           SMC_NETLINK_GET_LINK_SMCR);
328         if (!nlh)
329                 goto errmsg;
330
331         attrs = nla_nest_start(skb, SMC_GEN_LINK_SMCR);
332         if (!attrs)
333                 goto errout;
334
335         if (nla_put_u8(skb, SMC_NLA_LINK_ID, link->link_id))
336                 goto errattr;
337         if (nla_put_u32(skb, SMC_NLA_LINK_STATE, link->state))
338                 goto errattr;
339         if (nla_put_u32(skb, SMC_NLA_LINK_CONN_CNT,
340                         atomic_read(&link->conn_cnt)))
341                 goto errattr;
342         if (nla_put_u8(skb, SMC_NLA_LINK_IB_PORT, link->ibport))
343                 goto errattr;
344         if (nla_put_u32(skb, SMC_NLA_LINK_NET_DEV, link->ndev_ifidx))
345                 goto errattr;
346         snprintf(smc_ibname, sizeof(smc_ibname), "%s", link->ibname);
347         if (nla_put_string(skb, SMC_NLA_LINK_IB_DEV, smc_ibname))
348                 goto errattr;
349         memcpy(&link_uid, link->link_uid, sizeof(link_uid));
350         if (nla_put_u32(skb, SMC_NLA_LINK_UID, link_uid))
351                 goto errattr;
352         memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
353         if (nla_put_u32(skb, SMC_NLA_LINK_PEER_UID, link_uid))
354                 goto errattr;
355         memset(smc_gid_target, 0, sizeof(smc_gid_target));
356         smc_gid_be16_convert(smc_gid_target, link->gid);
357         if (nla_put_string(skb, SMC_NLA_LINK_GID, smc_gid_target))
358                 goto errattr;
359         memset(smc_gid_target, 0, sizeof(smc_gid_target));
360         smc_gid_be16_convert(smc_gid_target, link->peer_gid);
361         if (nla_put_string(skb, SMC_NLA_LINK_PEER_GID, smc_gid_target))
362                 goto errattr;
363
364         nla_nest_end(skb, attrs);
365         genlmsg_end(skb, nlh);
366         return 0;
367 errattr:
368         nla_nest_cancel(skb, attrs);
369 errout:
370         genlmsg_cancel(skb, nlh);
371 errmsg:
372         return -EMSGSIZE;
373 }
374
375 static int smc_nl_handle_lgr(struct smc_link_group *lgr,
376                              struct sk_buff *skb,
377                              struct netlink_callback *cb,
378                              bool list_links)
379 {
380         void *nlh;
381         int i;
382
383         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
384                           &smc_gen_nl_family, NLM_F_MULTI,
385                           SMC_NETLINK_GET_LGR_SMCR);
386         if (!nlh)
387                 goto errmsg;
388         if (smc_nl_fill_lgr(lgr, skb, cb))
389                 goto errout;
390
391         genlmsg_end(skb, nlh);
392         if (!list_links)
393                 goto out;
394         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
395                 if (!smc_link_usable(&lgr->lnk[i]))
396                         continue;
397                 if (smc_nl_fill_lgr_link(lgr, &lgr->lnk[i], skb, cb))
398                         goto errout;
399         }
400 out:
401         return 0;
402
403 errout:
404         genlmsg_cancel(skb, nlh);
405 errmsg:
406         return -EMSGSIZE;
407 }
408
409 static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
410                                  struct sk_buff *skb,
411                                  struct netlink_callback *cb,
412                                  bool list_links)
413 {
414         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
415         struct smc_link_group *lgr;
416         int snum = cb_ctx->pos[0];
417         int num = 0;
418
419         spin_lock_bh(&smc_lgr->lock);
420         list_for_each_entry(lgr, &smc_lgr->list, list) {
421                 if (num < snum)
422                         goto next;
423                 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
424                         goto errout;
425 next:
426                 num++;
427         }
428 errout:
429         spin_unlock_bh(&smc_lgr->lock);
430         cb_ctx->pos[0] = num;
431 }
432
433 static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
434                                 struct sk_buff *skb,
435                                 struct netlink_callback *cb)
436 {
437         char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
438         char smc_pnet[SMC_MAX_PNETID_LEN + 1];
439         char smc_eid[SMC_MAX_EID_LEN + 1];
440         struct nlattr *v2_attrs;
441         struct nlattr *attrs;
442         void *nlh;
443
444         nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
445                           &smc_gen_nl_family, NLM_F_MULTI,
446                           SMC_NETLINK_GET_LGR_SMCD);
447         if (!nlh)
448                 goto errmsg;
449
450         attrs = nla_nest_start(skb, SMC_GEN_LGR_SMCD);
451         if (!attrs)
452                 goto errout;
453
454         if (nla_put_u32(skb, SMC_NLA_LGR_D_ID, *((u32 *)&lgr->id)))
455                 goto errattr;
456         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_GID, lgr->smcd->local_gid,
457                               SMC_NLA_LGR_D_PAD))
458                 goto errattr;
459         if (nla_put_u64_64bit(skb, SMC_NLA_LGR_D_PEER_GID, lgr->peer_gid,
460                               SMC_NLA_LGR_D_PAD))
461                 goto errattr;
462         if (nla_put_u8(skb, SMC_NLA_LGR_D_VLAN_ID, lgr->vlan_id))
463                 goto errattr;
464         if (nla_put_u32(skb, SMC_NLA_LGR_D_CONNS_NUM, lgr->conns_num))
465                 goto errattr;
466         if (nla_put_u32(skb, SMC_NLA_LGR_D_CHID, smc_ism_get_chid(lgr->smcd)))
467                 goto errattr;
468         memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
469         smc_pnet[SMC_MAX_PNETID_LEN] = 0;
470         if (nla_put_string(skb, SMC_NLA_LGR_D_PNETID, smc_pnet))
471                 goto errattr;
472
473         v2_attrs = nla_nest_start(skb, SMC_NLA_LGR_V2);
474         if (!v2_attrs)
475                 goto errattr;
476         if (nla_put_u8(skb, SMC_NLA_LGR_V2_VER, lgr->smc_version))
477                 goto errv2attr;
478         if (nla_put_u8(skb, SMC_NLA_LGR_V2_REL, lgr->peer_smc_release))
479                 goto errv2attr;
480         if (nla_put_u8(skb, SMC_NLA_LGR_V2_OS, lgr->peer_os))
481                 goto errv2attr;
482         memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
483         smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
484         if (nla_put_string(skb, SMC_NLA_LGR_V2_PEER_HOST, smc_host))
485                 goto errv2attr;
486         memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
487         smc_eid[SMC_MAX_EID_LEN] = 0;
488         if (nla_put_string(skb, SMC_NLA_LGR_V2_NEG_EID, smc_eid))
489                 goto errv2attr;
490
491         nla_nest_end(skb, v2_attrs);
492         nla_nest_end(skb, attrs);
493         genlmsg_end(skb, nlh);
494         return 0;
495
496 errv2attr:
497         nla_nest_cancel(skb, v2_attrs);
498 errattr:
499         nla_nest_cancel(skb, attrs);
500 errout:
501         genlmsg_cancel(skb, nlh);
502 errmsg:
503         return -EMSGSIZE;
504 }
505
506 static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
507                                   struct sk_buff *skb,
508                                   struct netlink_callback *cb)
509 {
510         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
511         struct smc_link_group *lgr;
512         int snum = cb_ctx->pos[1];
513         int rc = 0, num = 0;
514
515         spin_lock_bh(&dev->lgr_lock);
516         list_for_each_entry(lgr, &dev->lgr_list, list) {
517                 if (!lgr->is_smcd)
518                         continue;
519                 if (num < snum)
520                         goto next;
521                 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
522                 if (rc)
523                         goto errout;
524 next:
525                 num++;
526         }
527 errout:
528         spin_unlock_bh(&dev->lgr_lock);
529         cb_ctx->pos[1] = num;
530         return rc;
531 }
532
533 static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
534                                 struct sk_buff *skb,
535                                 struct netlink_callback *cb)
536 {
537         struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
538         struct smcd_dev *smcd_dev;
539         int snum = cb_ctx->pos[0];
540         int rc = 0, num = 0;
541
542         mutex_lock(&dev_list->mutex);
543         list_for_each_entry(smcd_dev, &dev_list->list, list) {
544                 if (list_empty(&smcd_dev->lgr_list))
545                         continue;
546                 if (num < snum)
547                         goto next;
548                 rc = smc_nl_handle_smcd_lgr(smcd_dev, skb, cb);
549                 if (rc)
550                         goto errout;
551 next:
552                 num++;
553         }
554 errout:
555         mutex_unlock(&dev_list->mutex);
556         cb_ctx->pos[0] = num;
557         return rc;
558 }
559
560 int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
561 {
562         bool list_links = false;
563
564         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
565         return skb->len;
566 }
567
568 int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
569 {
570         bool list_links = true;
571
572         smc_nl_fill_lgr_list(&smc_lgr_list, skb, cb, list_links);
573         return skb->len;
574 }
575
576 int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
577 {
578         smc_nl_fill_smcd_dev(&smcd_dev_list, skb, cb);
579         return skb->len;
580 }
581
582 void smc_lgr_cleanup_early(struct smc_connection *conn)
583 {
584         struct smc_link_group *lgr = conn->lgr;
585         struct list_head *lgr_list;
586         spinlock_t *lgr_lock;
587
588         if (!lgr)
589                 return;
590
591         smc_conn_free(conn);
592         lgr_list = smc_lgr_list_head(lgr, &lgr_lock);
593         spin_lock_bh(lgr_lock);
594         /* do not use this link group for new connections */
595         if (!list_empty(lgr_list))
596                 list_del_init(lgr_list);
597         spin_unlock_bh(lgr_lock);
598         __smc_lgr_terminate(lgr, true);
599 }
600
601 static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
602 {
603         int i;
604
605         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
606                 struct smc_link *lnk = &lgr->lnk[i];
607
608                 if (smc_link_usable(lnk))
609                         lnk->state = SMC_LNK_INACTIVE;
610         }
611         wake_up_all(&lgr->llc_msg_waiter);
612         wake_up_all(&lgr->llc_flow_waiter);
613 }
614
615 static void smc_lgr_free(struct smc_link_group *lgr);
616
617 static void smc_lgr_free_work(struct work_struct *work)
618 {
619         struct smc_link_group *lgr = container_of(to_delayed_work(work),
620                                                   struct smc_link_group,
621                                                   free_work);
622         spinlock_t *lgr_lock;
623         bool conns;
624
625         smc_lgr_list_head(lgr, &lgr_lock);
626         spin_lock_bh(lgr_lock);
627         if (lgr->freeing) {
628                 spin_unlock_bh(lgr_lock);
629                 return;
630         }
631         read_lock_bh(&lgr->conns_lock);
632         conns = RB_EMPTY_ROOT(&lgr->conns_all);
633         read_unlock_bh(&lgr->conns_lock);
634         if (!conns) { /* number of lgr connections is no longer zero */
635                 spin_unlock_bh(lgr_lock);
636                 return;
637         }
638         list_del_init(&lgr->list); /* remove from smc_lgr_list */
639         lgr->freeing = 1; /* this instance does the freeing, no new schedule */
640         spin_unlock_bh(lgr_lock);
641         cancel_delayed_work(&lgr->free_work);
642
643         if (!lgr->is_smcd && !lgr->terminating)
644                 smc_llc_send_link_delete_all(lgr, true,
645                                              SMC_LLC_DEL_PROG_INIT_TERM);
646         if (lgr->is_smcd && !lgr->terminating)
647                 smc_ism_signal_shutdown(lgr);
648         if (!lgr->is_smcd)
649                 smcr_lgr_link_deactivate_all(lgr);
650         smc_lgr_free(lgr);
651 }
652
653 static void smc_lgr_terminate_work(struct work_struct *work)
654 {
655         struct smc_link_group *lgr = container_of(work, struct smc_link_group,
656                                                   terminate_work);
657
658         __smc_lgr_terminate(lgr, true);
659 }
660
661 /* return next unique link id for the lgr */
662 static u8 smcr_next_link_id(struct smc_link_group *lgr)
663 {
664         u8 link_id;
665         int i;
666
667         while (1) {
668                 link_id = ++lgr->next_link_id;
669                 if (!link_id)   /* skip zero as link_id */
670                         link_id = ++lgr->next_link_id;
671                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
672                         if (smc_link_usable(&lgr->lnk[i]) &&
673                             lgr->lnk[i].link_id == link_id)
674                                 continue;
675                 }
676                 break;
677         }
678         return link_id;
679 }
680
681 static void smcr_copy_dev_info_to_link(struct smc_link *link)
682 {
683         struct smc_ib_device *smcibdev = link->smcibdev;
684
685         snprintf(link->ibname, sizeof(link->ibname), "%s",
686                  smcibdev->ibdev->name);
687         link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
688 }
689
690 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
691                    u8 link_idx, struct smc_init_info *ini)
692 {
693         u8 rndvec[3];
694         int rc;
695
696         get_device(&ini->ib_dev->ibdev->dev);
697         atomic_inc(&ini->ib_dev->lnk_cnt);
698         lnk->link_id = smcr_next_link_id(lgr);
699         lnk->lgr = lgr;
700         lnk->link_idx = link_idx;
701         lnk->smcibdev = ini->ib_dev;
702         lnk->ibport = ini->ib_port;
703         smc_ibdev_cnt_inc(lnk);
704         smcr_copy_dev_info_to_link(lnk);
705         lnk->path_mtu = ini->ib_dev->pattr[ini->ib_port - 1].active_mtu;
706         atomic_set(&lnk->conn_cnt, 0);
707         smc_llc_link_set_uid(lnk);
708         INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
709         if (!ini->ib_dev->initialized) {
710                 rc = (int)smc_ib_setup_per_ibdev(ini->ib_dev);
711                 if (rc)
712                         goto out;
713         }
714         get_random_bytes(rndvec, sizeof(rndvec));
715         lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
716                 (rndvec[2] << 16);
717         rc = smc_ib_determine_gid(lnk->smcibdev, lnk->ibport,
718                                   ini->vlan_id, lnk->gid, &lnk->sgid_index);
719         if (rc)
720                 goto out;
721         rc = smc_llc_link_init(lnk);
722         if (rc)
723                 goto out;
724         rc = smc_wr_alloc_link_mem(lnk);
725         if (rc)
726                 goto clear_llc_lnk;
727         rc = smc_ib_create_protection_domain(lnk);
728         if (rc)
729                 goto free_link_mem;
730         rc = smc_ib_create_queue_pair(lnk);
731         if (rc)
732                 goto dealloc_pd;
733         rc = smc_wr_create_link(lnk);
734         if (rc)
735                 goto destroy_qp;
736         lnk->state = SMC_LNK_ACTIVATING;
737         return 0;
738
739 destroy_qp:
740         smc_ib_destroy_queue_pair(lnk);
741 dealloc_pd:
742         smc_ib_dealloc_protection_domain(lnk);
743 free_link_mem:
744         smc_wr_free_link_mem(lnk);
745 clear_llc_lnk:
746         smc_llc_link_clear(lnk, false);
747 out:
748         smc_ibdev_cnt_dec(lnk);
749         put_device(&ini->ib_dev->ibdev->dev);
750         memset(lnk, 0, sizeof(struct smc_link));
751         lnk->state = SMC_LNK_UNUSED;
752         if (!atomic_dec_return(&ini->ib_dev->lnk_cnt))
753                 wake_up(&ini->ib_dev->lnks_deleted);
754         return rc;
755 }
756
757 /* create a new SMC link group */
758 static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
759 {
760         struct smc_link_group *lgr;
761         struct list_head *lgr_list;
762         struct smc_link *lnk;
763         spinlock_t *lgr_lock;
764         u8 link_idx;
765         int rc = 0;
766         int i;
767
768         if (ini->is_smcd && ini->vlan_id) {
769                 if (smc_ism_get_vlan(ini->ism_dev[ini->ism_selected],
770                                      ini->vlan_id)) {
771                         rc = SMC_CLC_DECL_ISMVLANERR;
772                         goto out;
773                 }
774         }
775
776         lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
777         if (!lgr) {
778                 rc = SMC_CLC_DECL_MEM;
779                 goto ism_put_vlan;
780         }
781         lgr->tx_wq = alloc_workqueue("smc_tx_wq-%*phN", 0, 0,
782                                      SMC_LGR_ID_SIZE, &lgr->id);
783         if (!lgr->tx_wq) {
784                 rc = -ENOMEM;
785                 goto free_lgr;
786         }
787         lgr->is_smcd = ini->is_smcd;
788         lgr->sync_err = 0;
789         lgr->terminating = 0;
790         lgr->freeing = 0;
791         lgr->vlan_id = ini->vlan_id;
792         mutex_init(&lgr->sndbufs_lock);
793         mutex_init(&lgr->rmbs_lock);
794         rwlock_init(&lgr->conns_lock);
795         for (i = 0; i < SMC_RMBE_SIZES; i++) {
796                 INIT_LIST_HEAD(&lgr->sndbufs[i]);
797                 INIT_LIST_HEAD(&lgr->rmbs[i]);
798         }
799         lgr->next_link_id = 0;
800         smc_lgr_list.num += SMC_LGR_NUM_INCR;
801         memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
802         INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
803         INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
804         lgr->conns_all = RB_ROOT;
805         if (ini->is_smcd) {
806                 /* SMC-D specific settings */
807                 get_device(&ini->ism_dev[ini->ism_selected]->dev);
808                 lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
809                 lgr->smcd = ini->ism_dev[ini->ism_selected];
810                 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
811                 lgr_lock = &lgr->smcd->lgr_lock;
812                 lgr->smc_version = ini->smcd_version;
813                 lgr->peer_shutdown = 0;
814                 atomic_inc(&ini->ism_dev[ini->ism_selected]->lgr_cnt);
815         } else {
816                 /* SMC-R specific settings */
817                 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
818                 memcpy(lgr->peer_systemid, ini->ib_lcl->id_for_peer,
819                        SMC_SYSTEMID_LEN);
820                 memcpy(lgr->pnet_id, ini->ib_dev->pnetid[ini->ib_port - 1],
821                        SMC_MAX_PNETID_LEN);
822                 smc_llc_lgr_init(lgr, smc);
823
824                 link_idx = SMC_SINGLE_LINK;
825                 lnk = &lgr->lnk[link_idx];
826                 rc = smcr_link_init(lgr, lnk, link_idx, ini);
827                 if (rc)
828                         goto free_wq;
829                 lgr_list = &smc_lgr_list.list;
830                 lgr_lock = &smc_lgr_list.lock;
831                 atomic_inc(&lgr_cnt);
832         }
833         smc->conn.lgr = lgr;
834         spin_lock_bh(lgr_lock);
835         list_add_tail(&lgr->list, lgr_list);
836         spin_unlock_bh(lgr_lock);
837         return 0;
838
839 free_wq:
840         destroy_workqueue(lgr->tx_wq);
841 free_lgr:
842         kfree(lgr);
843 ism_put_vlan:
844         if (ini->is_smcd && ini->vlan_id)
845                 smc_ism_put_vlan(ini->ism_dev[ini->ism_selected], ini->vlan_id);
846 out:
847         if (rc < 0) {
848                 if (rc == -ENOMEM)
849                         rc = SMC_CLC_DECL_MEM;
850                 else
851                         rc = SMC_CLC_DECL_INTERR;
852         }
853         return rc;
854 }
855
856 static int smc_write_space(struct smc_connection *conn)
857 {
858         int buffer_len = conn->peer_rmbe_size;
859         union smc_host_cursor prod;
860         union smc_host_cursor cons;
861         int space;
862
863         smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn);
864         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
865         /* determine rx_buf space */
866         space = buffer_len - smc_curs_diff(buffer_len, &cons, &prod);
867         return space;
868 }
869
870 static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
871                              struct smc_wr_buf *wr_buf)
872 {
873         struct smc_connection *conn = &smc->conn;
874         union smc_host_cursor cons, fin;
875         int rc = 0;
876         int diff;
877
878         smc_curs_copy(&conn->tx_curs_sent, &conn->tx_curs_fin, conn);
879         smc_curs_copy(&fin, &conn->local_tx_ctrl_fin, conn);
880         /* set prod cursor to old state, enforce tx_rdma_writes() */
881         smc_curs_copy(&conn->local_tx_ctrl.prod, &fin, conn);
882         smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn);
883
884         if (smc_curs_comp(conn->peer_rmbe_size, &cons, &fin) < 0) {
885                 /* cons cursor advanced more than fin, and prod was set
886                  * fin above, so now prod is smaller than cons. Fix that.
887                  */
888                 diff = smc_curs_diff(conn->peer_rmbe_size, &fin, &cons);
889                 smc_curs_add(conn->sndbuf_desc->len,
890                              &conn->tx_curs_sent, diff);
891                 smc_curs_add(conn->sndbuf_desc->len,
892                              &conn->tx_curs_fin, diff);
893
894                 smp_mb__before_atomic();
895                 atomic_add(diff, &conn->sndbuf_space);
896                 smp_mb__after_atomic();
897
898                 smc_curs_add(conn->peer_rmbe_size,
899                              &conn->local_tx_ctrl.prod, diff);
900                 smc_curs_add(conn->peer_rmbe_size,
901                              &conn->local_tx_ctrl_fin, diff);
902         }
903         /* recalculate, value is used by tx_rdma_writes() */
904         atomic_set(&smc->conn.peer_rmbe_space, smc_write_space(conn));
905
906         if (smc->sk.sk_state != SMC_INIT &&
907             smc->sk.sk_state != SMC_CLOSED) {
908                 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
909                 if (!rc) {
910                         queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, 0);
911                         smc->sk.sk_data_ready(&smc->sk);
912                 }
913         } else {
914                 smc_wr_tx_put_slot(conn->lnk,
915                                    (struct smc_wr_tx_pend_priv *)pend);
916         }
917         return rc;
918 }
919
920 void smc_switch_link_and_count(struct smc_connection *conn,
921                                struct smc_link *to_lnk)
922 {
923         atomic_dec(&conn->lnk->conn_cnt);
924         conn->lnk = to_lnk;
925         atomic_inc(&conn->lnk->conn_cnt);
926 }
927
928 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
929                                   struct smc_link *from_lnk, bool is_dev_err)
930 {
931         struct smc_link *to_lnk = NULL;
932         struct smc_cdc_tx_pend *pend;
933         struct smc_connection *conn;
934         struct smc_wr_buf *wr_buf;
935         struct smc_sock *smc;
936         struct rb_node *node;
937         int i, rc = 0;
938
939         /* link is inactive, wake up tx waiters */
940         smc_wr_wakeup_tx_wait(from_lnk);
941
942         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
943                 if (!smc_link_active(&lgr->lnk[i]) || i == from_lnk->link_idx)
944                         continue;
945                 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
946                     from_lnk->ibport == lgr->lnk[i].ibport) {
947                         continue;
948                 }
949                 to_lnk = &lgr->lnk[i];
950                 break;
951         }
952         if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
953                 smc_lgr_terminate_sched(lgr);
954                 return NULL;
955         }
956 again:
957         read_lock_bh(&lgr->conns_lock);
958         for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
959                 conn = rb_entry(node, struct smc_connection, alert_node);
960                 if (conn->lnk != from_lnk)
961                         continue;
962                 smc = container_of(conn, struct smc_sock, conn);
963                 /* conn->lnk not yet set in SMC_INIT state */
964                 if (smc->sk.sk_state == SMC_INIT)
965                         continue;
966                 if (smc->sk.sk_state == SMC_CLOSED ||
967                     smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
968                     smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
969                     smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
970                     smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
971                     smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
972                     smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
973                     smc->sk.sk_state == SMC_PEERABORTWAIT ||
974                     smc->sk.sk_state == SMC_PROCESSABORT) {
975                         spin_lock_bh(&conn->send_lock);
976                         smc_switch_link_and_count(conn, to_lnk);
977                         spin_unlock_bh(&conn->send_lock);
978                         continue;
979                 }
980                 sock_hold(&smc->sk);
981                 read_unlock_bh(&lgr->conns_lock);
982                 /* pre-fetch buffer outside of send_lock, might sleep */
983                 rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
984                 if (rc)
985                         goto err_out;
986                 /* avoid race with smcr_tx_sndbuf_nonempty() */
987                 spin_lock_bh(&conn->send_lock);
988                 smc_switch_link_and_count(conn, to_lnk);
989                 rc = smc_switch_cursor(smc, pend, wr_buf);
990                 spin_unlock_bh(&conn->send_lock);
991                 sock_put(&smc->sk);
992                 if (rc)
993                         goto err_out;
994                 goto again;
995         }
996         read_unlock_bh(&lgr->conns_lock);
997         smc_wr_tx_link_put(to_lnk);
998         return to_lnk;
999
1000 err_out:
1001         smcr_link_down_cond_sched(to_lnk);
1002         smc_wr_tx_link_put(to_lnk);
1003         return NULL;
1004 }
1005
1006 static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
1007                            struct smc_link_group *lgr)
1008 {
1009         int rc;
1010
1011         if (rmb_desc->is_conf_rkey && !list_empty(&lgr->list)) {
1012                 /* unregister rmb with peer */
1013                 rc = smc_llc_flow_initiate(lgr, SMC_LLC_FLOW_RKEY);
1014                 if (!rc) {
1015                         /* protect against smc_llc_cli_rkey_exchange() */
1016                         mutex_lock(&lgr->llc_conf_mutex);
1017                         smc_llc_do_delete_rkey(lgr, rmb_desc);
1018                         rmb_desc->is_conf_rkey = false;
1019                         mutex_unlock(&lgr->llc_conf_mutex);
1020                         smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
1021                 }
1022         }
1023
1024         if (rmb_desc->is_reg_err) {
1025                 /* buf registration failed, reuse not possible */
1026                 mutex_lock(&lgr->rmbs_lock);
1027                 list_del(&rmb_desc->list);
1028                 mutex_unlock(&lgr->rmbs_lock);
1029
1030                 smc_buf_free(lgr, true, rmb_desc);
1031         } else {
1032                 rmb_desc->used = 0;
1033         }
1034 }
1035
1036 static void smc_buf_unuse(struct smc_connection *conn,
1037                           struct smc_link_group *lgr)
1038 {
1039         if (conn->sndbuf_desc)
1040                 conn->sndbuf_desc->used = 0;
1041         if (conn->rmb_desc && lgr->is_smcd)
1042                 conn->rmb_desc->used = 0;
1043         else if (conn->rmb_desc)
1044                 smcr_buf_unuse(conn->rmb_desc, lgr);
1045 }
1046
1047 /* remove a finished connection from its link group */
1048 void smc_conn_free(struct smc_connection *conn)
1049 {
1050         struct smc_link_group *lgr = conn->lgr;
1051
1052         if (!lgr)
1053                 return;
1054         if (lgr->is_smcd) {
1055                 if (!list_empty(&lgr->list))
1056                         smc_ism_unset_conn(conn);
1057                 tasklet_kill(&conn->rx_tsklet);
1058         } else {
1059                 smc_cdc_tx_dismiss_slots(conn);
1060                 if (current_work() != &conn->abort_work)
1061                         cancel_work_sync(&conn->abort_work);
1062         }
1063         if (!list_empty(&lgr->list)) {
1064                 smc_lgr_unregister_conn(conn);
1065                 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1066         }
1067
1068         if (!lgr->conns_num)
1069                 smc_lgr_schedule_free_work(lgr);
1070 }
1071
1072 /* unregister a link from a buf_desc */
1073 static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1074                                 struct smc_link *lnk)
1075 {
1076         if (is_rmb)
1077                 buf_desc->is_reg_mr[lnk->link_idx] = false;
1078         if (!buf_desc->is_map_ib[lnk->link_idx])
1079                 return;
1080         if (is_rmb) {
1081                 if (buf_desc->mr_rx[lnk->link_idx]) {
1082                         smc_ib_put_memory_region(
1083                                         buf_desc->mr_rx[lnk->link_idx]);
1084                         buf_desc->mr_rx[lnk->link_idx] = NULL;
1085                 }
1086                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_FROM_DEVICE);
1087         } else {
1088                 smc_ib_buf_unmap_sg(lnk, buf_desc, DMA_TO_DEVICE);
1089         }
1090         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1091         buf_desc->is_map_ib[lnk->link_idx] = false;
1092 }
1093
1094 /* unmap all buffers of lgr for a deleted link */
1095 static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1096 {
1097         struct smc_link_group *lgr = lnk->lgr;
1098         struct smc_buf_desc *buf_desc, *bf;
1099         int i;
1100
1101         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1102                 mutex_lock(&lgr->rmbs_lock);
1103                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1104                         smcr_buf_unmap_link(buf_desc, true, lnk);
1105                 mutex_unlock(&lgr->rmbs_lock);
1106                 mutex_lock(&lgr->sndbufs_lock);
1107                 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1108                                          list)
1109                         smcr_buf_unmap_link(buf_desc, false, lnk);
1110                 mutex_unlock(&lgr->sndbufs_lock);
1111         }
1112 }
1113
1114 static void smcr_rtoken_clear_link(struct smc_link *lnk)
1115 {
1116         struct smc_link_group *lgr = lnk->lgr;
1117         int i;
1118
1119         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1120                 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1121                 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1122         }
1123 }
1124
1125 /* must be called under lgr->llc_conf_mutex lock */
1126 void smcr_link_clear(struct smc_link *lnk, bool log)
1127 {
1128         struct smc_ib_device *smcibdev;
1129
1130         if (!lnk->lgr || lnk->state == SMC_LNK_UNUSED)
1131                 return;
1132         lnk->peer_qpn = 0;
1133         smc_llc_link_clear(lnk, log);
1134         smcr_buf_unmap_lgr(lnk);
1135         smcr_rtoken_clear_link(lnk);
1136         smc_ib_modify_qp_reset(lnk);
1137         smc_wr_free_link(lnk);
1138         smc_ib_destroy_queue_pair(lnk);
1139         smc_ib_dealloc_protection_domain(lnk);
1140         smc_wr_free_link_mem(lnk);
1141         smc_ibdev_cnt_dec(lnk);
1142         put_device(&lnk->smcibdev->ibdev->dev);
1143         smcibdev = lnk->smcibdev;
1144         memset(lnk, 0, sizeof(struct smc_link));
1145         lnk->state = SMC_LNK_UNUSED;
1146         if (!atomic_dec_return(&smcibdev->lnk_cnt))
1147                 wake_up(&smcibdev->lnks_deleted);
1148 }
1149
1150 static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1151                           struct smc_buf_desc *buf_desc)
1152 {
1153         int i;
1154
1155         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1156                 smcr_buf_unmap_link(buf_desc, is_rmb, &lgr->lnk[i]);
1157
1158         if (buf_desc->pages)
1159                 __free_pages(buf_desc->pages, buf_desc->order);
1160         kfree(buf_desc);
1161 }
1162
1163 static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1164                           struct smc_buf_desc *buf_desc)
1165 {
1166         if (is_dmb) {
1167                 /* restore original buf len */
1168                 buf_desc->len += sizeof(struct smcd_cdc_msg);
1169                 smc_ism_unregister_dmb(lgr->smcd, buf_desc);
1170         } else {
1171                 kfree(buf_desc->cpu_addr);
1172         }
1173         kfree(buf_desc);
1174 }
1175
1176 static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1177                          struct smc_buf_desc *buf_desc)
1178 {
1179         if (lgr->is_smcd)
1180                 smcd_buf_free(lgr, is_rmb, buf_desc);
1181         else
1182                 smcr_buf_free(lgr, is_rmb, buf_desc);
1183 }
1184
1185 static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1186 {
1187         struct smc_buf_desc *buf_desc, *bf_desc;
1188         struct list_head *buf_list;
1189         int i;
1190
1191         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1192                 if (is_rmb)
1193                         buf_list = &lgr->rmbs[i];
1194                 else
1195                         buf_list = &lgr->sndbufs[i];
1196                 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1197                                          list) {
1198                         list_del(&buf_desc->list);
1199                         smc_buf_free(lgr, is_rmb, buf_desc);
1200                 }
1201         }
1202 }
1203
1204 static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1205 {
1206         /* free send buffers */
1207         __smc_lgr_free_bufs(lgr, false);
1208         /* free rmbs */
1209         __smc_lgr_free_bufs(lgr, true);
1210 }
1211
1212 /* remove a link group */
1213 static void smc_lgr_free(struct smc_link_group *lgr)
1214 {
1215         int i;
1216
1217         if (!lgr->is_smcd) {
1218                 mutex_lock(&lgr->llc_conf_mutex);
1219                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1220                         if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1221                                 smcr_link_clear(&lgr->lnk[i], false);
1222                 }
1223                 mutex_unlock(&lgr->llc_conf_mutex);
1224                 smc_llc_lgr_clear(lgr);
1225         }
1226
1227         smc_lgr_free_bufs(lgr);
1228         destroy_workqueue(lgr->tx_wq);
1229         if (lgr->is_smcd) {
1230                 smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
1231                 put_device(&lgr->smcd->dev);
1232                 if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
1233                         wake_up(&lgr->smcd->lgrs_deleted);
1234         } else {
1235                 if (!atomic_dec_return(&lgr_cnt))
1236                         wake_up(&lgrs_deleted);
1237         }
1238         kfree(lgr);
1239 }
1240
1241 static void smc_sk_wake_ups(struct smc_sock *smc)
1242 {
1243         smc->sk.sk_write_space(&smc->sk);
1244         smc->sk.sk_data_ready(&smc->sk);
1245         smc->sk.sk_state_change(&smc->sk);
1246 }
1247
1248 /* kill a connection */
1249 static void smc_conn_kill(struct smc_connection *conn, bool soft)
1250 {
1251         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1252
1253         if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1254                 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1255         else
1256                 smc_close_abort(conn);
1257         conn->killed = 1;
1258         smc->sk.sk_err = ECONNABORTED;
1259         smc_sk_wake_ups(smc);
1260         if (conn->lgr->is_smcd) {
1261                 smc_ism_unset_conn(conn);
1262                 if (soft)
1263                         tasklet_kill(&conn->rx_tsklet);
1264                 else
1265                         tasklet_unlock_wait(&conn->rx_tsklet);
1266         } else {
1267                 smc_cdc_tx_dismiss_slots(conn);
1268         }
1269         smc_lgr_unregister_conn(conn);
1270         smc_close_active_abort(smc);
1271 }
1272
1273 static void smc_lgr_cleanup(struct smc_link_group *lgr)
1274 {
1275         if (lgr->is_smcd) {
1276                 smc_ism_signal_shutdown(lgr);
1277         } else {
1278                 u32 rsn = lgr->llc_termination_rsn;
1279
1280                 if (!rsn)
1281                         rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1282                 smc_llc_send_link_delete_all(lgr, false, rsn);
1283                 smcr_lgr_link_deactivate_all(lgr);
1284         }
1285 }
1286
1287 /* terminate link group
1288  * @soft: true if link group shutdown can take its time
1289  *        false if immediate link group shutdown is required
1290  */
1291 static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1292 {
1293         struct smc_connection *conn;
1294         struct smc_sock *smc;
1295         struct rb_node *node;
1296
1297         if (lgr->terminating)
1298                 return; /* lgr already terminating */
1299         /* cancel free_work sync, will terminate when lgr->freeing is set */
1300         cancel_delayed_work_sync(&lgr->free_work);
1301         lgr->terminating = 1;
1302
1303         /* kill remaining link group connections */
1304         read_lock_bh(&lgr->conns_lock);
1305         node = rb_first(&lgr->conns_all);
1306         while (node) {
1307                 read_unlock_bh(&lgr->conns_lock);
1308                 conn = rb_entry(node, struct smc_connection, alert_node);
1309                 smc = container_of(conn, struct smc_sock, conn);
1310                 sock_hold(&smc->sk); /* sock_put below */
1311                 lock_sock(&smc->sk);
1312                 smc_conn_kill(conn, soft);
1313                 release_sock(&smc->sk);
1314                 sock_put(&smc->sk); /* sock_hold above */
1315                 read_lock_bh(&lgr->conns_lock);
1316                 node = rb_first(&lgr->conns_all);
1317         }
1318         read_unlock_bh(&lgr->conns_lock);
1319         smc_lgr_cleanup(lgr);
1320         smc_lgr_free(lgr);
1321 }
1322
1323 /* unlink link group and schedule termination */
1324 void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1325 {
1326         spinlock_t *lgr_lock;
1327
1328         smc_lgr_list_head(lgr, &lgr_lock);
1329         spin_lock_bh(lgr_lock);
1330         if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) {
1331                 spin_unlock_bh(lgr_lock);
1332                 return; /* lgr already terminating */
1333         }
1334         list_del_init(&lgr->list);
1335         lgr->freeing = 1;
1336         spin_unlock_bh(lgr_lock);
1337         schedule_work(&lgr->terminate_work);
1338 }
1339
1340 /* Called when peer lgr shutdown (regularly or abnormally) is received */
1341 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
1342 {
1343         struct smc_link_group *lgr, *l;
1344         LIST_HEAD(lgr_free_list);
1345
1346         /* run common cleanup function and build free list */
1347         spin_lock_bh(&dev->lgr_lock);
1348         list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1349                 if ((!peer_gid || lgr->peer_gid == peer_gid) &&
1350                     (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1351                         if (peer_gid) /* peer triggered termination */
1352                                 lgr->peer_shutdown = 1;
1353                         list_move(&lgr->list, &lgr_free_list);
1354                         lgr->freeing = 1;
1355                 }
1356         }
1357         spin_unlock_bh(&dev->lgr_lock);
1358
1359         /* cancel the regular free workers and actually free lgrs */
1360         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1361                 list_del_init(&lgr->list);
1362                 schedule_work(&lgr->terminate_work);
1363         }
1364 }
1365
1366 /* Called when an SMCD device is removed or the smc module is unloaded */
1367 void smc_smcd_terminate_all(struct smcd_dev *smcd)
1368 {
1369         struct smc_link_group *lgr, *lg;
1370         LIST_HEAD(lgr_free_list);
1371
1372         spin_lock_bh(&smcd->lgr_lock);
1373         list_splice_init(&smcd->lgr_list, &lgr_free_list);
1374         list_for_each_entry(lgr, &lgr_free_list, list)
1375                 lgr->freeing = 1;
1376         spin_unlock_bh(&smcd->lgr_lock);
1377
1378         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1379                 list_del_init(&lgr->list);
1380                 __smc_lgr_terminate(lgr, false);
1381         }
1382
1383         if (atomic_read(&smcd->lgr_cnt))
1384                 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1385 }
1386
1387 /* Called when an SMCR device is removed or the smc module is unloaded.
1388  * If smcibdev is given, all SMCR link groups using this device are terminated.
1389  * If smcibdev is NULL, all SMCR link groups are terminated.
1390  */
1391 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1392 {
1393         struct smc_link_group *lgr, *lg;
1394         LIST_HEAD(lgr_free_list);
1395         int i;
1396
1397         spin_lock_bh(&smc_lgr_list.lock);
1398         if (!smcibdev) {
1399                 list_splice_init(&smc_lgr_list.list, &lgr_free_list);
1400                 list_for_each_entry(lgr, &lgr_free_list, list)
1401                         lgr->freeing = 1;
1402         } else {
1403                 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1404                         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1405                                 if (lgr->lnk[i].smcibdev == smcibdev)
1406                                         smcr_link_down_cond_sched(&lgr->lnk[i]);
1407                         }
1408                 }
1409         }
1410         spin_unlock_bh(&smc_lgr_list.lock);
1411
1412         list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1413                 list_del_init(&lgr->list);
1414                 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1415                 __smc_lgr_terminate(lgr, false);
1416         }
1417
1418         if (smcibdev) {
1419                 if (atomic_read(&smcibdev->lnk_cnt))
1420                         wait_event(smcibdev->lnks_deleted,
1421                                    !atomic_read(&smcibdev->lnk_cnt));
1422         } else {
1423                 if (atomic_read(&lgr_cnt))
1424                         wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1425         }
1426 }
1427
1428 /* set new lgr type and clear all asymmetric link tagging */
1429 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1430 {
1431         char *lgr_type = "";
1432         int i;
1433
1434         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1435                 if (smc_link_usable(&lgr->lnk[i]))
1436                         lgr->lnk[i].link_is_asym = false;
1437         if (lgr->type == new_type)
1438                 return;
1439         lgr->type = new_type;
1440
1441         switch (lgr->type) {
1442         case SMC_LGR_NONE:
1443                 lgr_type = "NONE";
1444                 break;
1445         case SMC_LGR_SINGLE:
1446                 lgr_type = "SINGLE";
1447                 break;
1448         case SMC_LGR_SYMMETRIC:
1449                 lgr_type = "SYMMETRIC";
1450                 break;
1451         case SMC_LGR_ASYMMETRIC_PEER:
1452                 lgr_type = "ASYMMETRIC_PEER";
1453                 break;
1454         case SMC_LGR_ASYMMETRIC_LOCAL:
1455                 lgr_type = "ASYMMETRIC_LOCAL";
1456                 break;
1457         }
1458         pr_warn_ratelimited("smc: SMC-R lg %*phN state changed: "
1459                             "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1460                             lgr_type, lgr->pnet_id);
1461 }
1462
1463 /* set new lgr type and tag a link as asymmetric */
1464 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1465                             enum smc_lgr_type new_type, int asym_lnk_idx)
1466 {
1467         smcr_lgr_set_type(lgr, new_type);
1468         lgr->lnk[asym_lnk_idx].link_is_asym = true;
1469 }
1470
1471 /* abort connection, abort_work scheduled from tasklet context */
1472 static void smc_conn_abort_work(struct work_struct *work)
1473 {
1474         struct smc_connection *conn = container_of(work,
1475                                                    struct smc_connection,
1476                                                    abort_work);
1477         struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1478
1479         lock_sock(&smc->sk);
1480         smc_conn_kill(conn, true);
1481         release_sock(&smc->sk);
1482         sock_put(&smc->sk); /* sock_hold done by schedulers of abort_work */
1483 }
1484
1485 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1486 {
1487         struct smc_link_group *lgr, *n;
1488
1489         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1490                 struct smc_link *link;
1491
1492                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1493                             SMC_MAX_PNETID_LEN) ||
1494                     lgr->type == SMC_LGR_SYMMETRIC ||
1495                     lgr->type == SMC_LGR_ASYMMETRIC_PEER)
1496                         continue;
1497
1498                 /* trigger local add link processing */
1499                 link = smc_llc_usable_link(lgr);
1500                 if (link)
1501                         smc_llc_add_link_local(link);
1502         }
1503 }
1504
1505 /* link is down - switch connections to alternate link,
1506  * must be called under lgr->llc_conf_mutex lock
1507  */
1508 static void smcr_link_down(struct smc_link *lnk)
1509 {
1510         struct smc_link_group *lgr = lnk->lgr;
1511         struct smc_link *to_lnk;
1512         int del_link_id;
1513
1514         if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(&lgr->list))
1515                 return;
1516
1517         smc_ib_modify_qp_reset(lnk);
1518         to_lnk = smc_switch_conns(lgr, lnk, true);
1519         if (!to_lnk) { /* no backup link available */
1520                 smcr_link_clear(lnk, true);
1521                 return;
1522         }
1523         smcr_lgr_set_type(lgr, SMC_LGR_SINGLE);
1524         del_link_id = lnk->link_id;
1525
1526         if (lgr->role == SMC_SERV) {
1527                 /* trigger local delete link processing */
1528                 smc_llc_srv_delete_link_local(to_lnk, del_link_id);
1529         } else {
1530                 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1531                         /* another llc task is ongoing */
1532                         mutex_unlock(&lgr->llc_conf_mutex);
1533                         wait_event_timeout(lgr->llc_flow_waiter,
1534                                 (list_empty(&lgr->list) ||
1535                                  lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1536                                 SMC_LLC_WAIT_TIME);
1537                         mutex_lock(&lgr->llc_conf_mutex);
1538                 }
1539                 if (!list_empty(&lgr->list)) {
1540                         smc_llc_send_delete_link(to_lnk, del_link_id,
1541                                                  SMC_LLC_REQ, true,
1542                                                  SMC_LLC_DEL_LOST_PATH);
1543                         smcr_link_clear(lnk, true);
1544                 }
1545                 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1546         }
1547 }
1548
1549 /* must be called under lgr->llc_conf_mutex lock */
1550 void smcr_link_down_cond(struct smc_link *lnk)
1551 {
1552         if (smc_link_downing(&lnk->state))
1553                 smcr_link_down(lnk);
1554 }
1555
1556 /* will get the lgr->llc_conf_mutex lock */
1557 void smcr_link_down_cond_sched(struct smc_link *lnk)
1558 {
1559         if (smc_link_downing(&lnk->state))
1560                 schedule_work(&lnk->link_down_wrk);
1561 }
1562
1563 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1564 {
1565         struct smc_link_group *lgr, *n;
1566         int i;
1567
1568         list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1569                 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1570                             SMC_MAX_PNETID_LEN))
1571                         continue; /* lgr is not affected */
1572                 if (list_empty(&lgr->list))
1573                         continue;
1574                 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1575                         struct smc_link *lnk = &lgr->lnk[i];
1576
1577                         if (smc_link_usable(lnk) &&
1578                             lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1579                                 smcr_link_down_cond_sched(lnk);
1580                 }
1581         }
1582 }
1583
1584 static void smc_link_down_work(struct work_struct *work)
1585 {
1586         struct smc_link *link = container_of(work, struct smc_link,
1587                                              link_down_wrk);
1588         struct smc_link_group *lgr = link->lgr;
1589
1590         if (list_empty(&lgr->list))
1591                 return;
1592         wake_up_all(&lgr->llc_msg_waiter);
1593         mutex_lock(&lgr->llc_conf_mutex);
1594         smcr_link_down(link);
1595         mutex_unlock(&lgr->llc_conf_mutex);
1596 }
1597
1598 /* Determine vlan of internal TCP socket.
1599  * @vlan_id: address to store the determined vlan id into
1600  */
1601 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1602 {
1603         struct dst_entry *dst = sk_dst_get(clcsock->sk);
1604         struct net_device *ndev;
1605         int i, nest_lvl, rc = 0;
1606
1607         ini->vlan_id = 0;
1608         if (!dst) {
1609                 rc = -ENOTCONN;
1610                 goto out;
1611         }
1612         if (!dst->dev) {
1613                 rc = -ENODEV;
1614                 goto out_rel;
1615         }
1616
1617         ndev = dst->dev;
1618         if (is_vlan_dev(ndev)) {
1619                 ini->vlan_id = vlan_dev_vlan_id(ndev);
1620                 goto out_rel;
1621         }
1622
1623         rtnl_lock();
1624         nest_lvl = ndev->lower_level;
1625         for (i = 0; i < nest_lvl; i++) {
1626                 struct list_head *lower = &ndev->adj_list.lower;
1627
1628                 if (list_empty(lower))
1629                         break;
1630                 lower = lower->next;
1631                 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
1632                 if (is_vlan_dev(ndev)) {
1633                         ini->vlan_id = vlan_dev_vlan_id(ndev);
1634                         break;
1635                 }
1636         }
1637         rtnl_unlock();
1638
1639 out_rel:
1640         dst_release(dst);
1641 out:
1642         return rc;
1643 }
1644
1645 static bool smcr_lgr_match(struct smc_link_group *lgr,
1646                            struct smc_clc_msg_local *lcl,
1647                            enum smc_lgr_role role, u32 clcqpn)
1648 {
1649         int i;
1650
1651         if (memcmp(lgr->peer_systemid, lcl->id_for_peer, SMC_SYSTEMID_LEN) ||
1652             lgr->role != role)
1653                 return false;
1654
1655         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1656                 if (!smc_link_active(&lgr->lnk[i]))
1657                         continue;
1658                 if ((lgr->role == SMC_SERV || lgr->lnk[i].peer_qpn == clcqpn) &&
1659                     !memcmp(lgr->lnk[i].peer_gid, &lcl->gid, SMC_GID_SIZE) &&
1660                     !memcmp(lgr->lnk[i].peer_mac, lcl->mac, sizeof(lcl->mac)))
1661                         return true;
1662         }
1663         return false;
1664 }
1665
1666 static bool smcd_lgr_match(struct smc_link_group *lgr,
1667                            struct smcd_dev *smcismdev, u64 peer_gid)
1668 {
1669         return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1670 }
1671
1672 /* create a new SMC connection (and a new link group if necessary) */
1673 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1674 {
1675         struct smc_connection *conn = &smc->conn;
1676         struct list_head *lgr_list;
1677         struct smc_link_group *lgr;
1678         enum smc_lgr_role role;
1679         spinlock_t *lgr_lock;
1680         int rc = 0;
1681
1682         lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1683                                   &smc_lgr_list.list;
1684         lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1685                                   &smc_lgr_list.lock;
1686         ini->first_contact_local = 1;
1687         role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1688         if (role == SMC_CLNT && ini->first_contact_peer)
1689                 /* create new link group as well */
1690                 goto create;
1691
1692         /* determine if an existing link group can be reused */
1693         spin_lock_bh(lgr_lock);
1694         list_for_each_entry(lgr, lgr_list, list) {
1695                 write_lock_bh(&lgr->conns_lock);
1696                 if ((ini->is_smcd ?
1697                      smcd_lgr_match(lgr, ini->ism_dev[ini->ism_selected],
1698                                     ini->ism_peer_gid[ini->ism_selected]) :
1699                      smcr_lgr_match(lgr, ini->ib_lcl, role, ini->ib_clcqpn)) &&
1700                     !lgr->sync_err &&
1701                     (ini->smcd_version == SMC_V2 ||
1702                      lgr->vlan_id == ini->vlan_id) &&
1703                     (role == SMC_CLNT || ini->is_smcd ||
1704                      lgr->conns_num < SMC_RMBS_PER_LGR_MAX)) {
1705                         /* link group found */
1706                         ini->first_contact_local = 0;
1707                         conn->lgr = lgr;
1708                         rc = smc_lgr_register_conn(conn, false);
1709                         write_unlock_bh(&lgr->conns_lock);
1710                         if (!rc && delayed_work_pending(&lgr->free_work))
1711                                 cancel_delayed_work(&lgr->free_work);
1712                         break;
1713                 }
1714                 write_unlock_bh(&lgr->conns_lock);
1715         }
1716         spin_unlock_bh(lgr_lock);
1717         if (rc)
1718                 return rc;
1719
1720         if (role == SMC_CLNT && !ini->first_contact_peer &&
1721             ini->first_contact_local) {
1722                 /* Server reuses a link group, but Client wants to start
1723                  * a new one
1724                  * send out_of_sync decline, reason synchr. error
1725                  */
1726                 return SMC_CLC_DECL_SYNCERR;
1727         }
1728
1729 create:
1730         if (ini->first_contact_local) {
1731                 rc = smc_lgr_create(smc, ini);
1732                 if (rc)
1733                         goto out;
1734                 lgr = conn->lgr;
1735                 write_lock_bh(&lgr->conns_lock);
1736                 rc = smc_lgr_register_conn(conn, true);
1737                 write_unlock_bh(&lgr->conns_lock);
1738                 if (rc)
1739                         goto out;
1740         }
1741         conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1742         conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1743         conn->urg_state = SMC_URG_READ;
1744         INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1745         if (ini->is_smcd) {
1746                 conn->rx_off = sizeof(struct smcd_cdc_msg);
1747                 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1748         } else {
1749                 conn->rx_off = 0;
1750         }
1751 #ifndef KERNEL_HAS_ATOMIC64
1752         spin_lock_init(&conn->acurs_lock);
1753 #endif
1754
1755 out:
1756         return rc;
1757 }
1758
1759 #define SMCD_DMBE_SIZES         6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1760 #define SMCR_RMBE_SIZES         5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
1761
1762 /* convert the RMB size into the compressed notation (minimum 16K, see
1763  * SMCD/R_DMBE_SIZES.
1764  * In contrast to plain ilog2, this rounds towards the next power of 2,
1765  * so the socket application gets at least its desired sndbuf / rcvbuf size.
1766  */
1767 static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
1768 {
1769         const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
1770         u8 compressed;
1771
1772         if (size <= SMC_BUF_MIN_SIZE)
1773                 return 0;
1774
1775         size = (size - 1) >> 14;  /* convert to 16K multiple */
1776         compressed = min_t(u8, ilog2(size) + 1,
1777                            is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
1778
1779         if (!is_smcd && is_rmb)
1780                 /* RMBs are backed by & limited to max size of scatterlists */
1781                 compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
1782
1783         return compressed;
1784 }
1785
1786 /* convert the RMB size from compressed notation into integer */
1787 int smc_uncompress_bufsize(u8 compressed)
1788 {
1789         u32 size;
1790
1791         size = 0x00000001 << (((int)compressed) + 14);
1792         return (int)size;
1793 }
1794
1795 /* try to reuse a sndbuf or rmb description slot for a certain
1796  * buffer size; if not available, return NULL
1797  */
1798 static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
1799                                              struct mutex *lock,
1800                                              struct list_head *buf_list)
1801 {
1802         struct smc_buf_desc *buf_slot;
1803
1804         mutex_lock(lock);
1805         list_for_each_entry(buf_slot, buf_list, list) {
1806                 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
1807                         mutex_unlock(lock);
1808                         return buf_slot;
1809                 }
1810         }
1811         mutex_unlock(lock);
1812         return NULL;
1813 }
1814
1815 /* one of the conditions for announcing a receiver's current window size is
1816  * that it "results in a minimum increase in the window size of 10% of the
1817  * receive buffer space" [RFC7609]
1818  */
1819 static inline int smc_rmb_wnd_update_limit(int rmbe_size)
1820 {
1821         return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
1822 }
1823
1824 /* map an rmb buf to a link */
1825 static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1826                              struct smc_link *lnk)
1827 {
1828         int rc;
1829
1830         if (buf_desc->is_map_ib[lnk->link_idx])
1831                 return 0;
1832
1833         rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], 1, GFP_KERNEL);
1834         if (rc)
1835                 return rc;
1836         sg_set_buf(buf_desc->sgt[lnk->link_idx].sgl,
1837                    buf_desc->cpu_addr, buf_desc->len);
1838
1839         /* map sg table to DMA address */
1840         rc = smc_ib_buf_map_sg(lnk, buf_desc,
1841                                is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
1842         /* SMC protocol depends on mapping to one DMA address only */
1843         if (rc != 1) {
1844                 rc = -EAGAIN;
1845                 goto free_table;
1846         }
1847
1848         /* create a new memory region for the RMB */
1849         if (is_rmb) {
1850                 rc = smc_ib_get_memory_region(lnk->roce_pd,
1851                                               IB_ACCESS_REMOTE_WRITE |
1852                                               IB_ACCESS_LOCAL_WRITE,
1853                                               buf_desc, lnk->link_idx);
1854                 if (rc)
1855                         goto buf_unmap;
1856                 smc_ib_sync_sg_for_device(lnk, buf_desc, DMA_FROM_DEVICE);
1857         }
1858         buf_desc->is_map_ib[lnk->link_idx] = true;
1859         return 0;
1860
1861 buf_unmap:
1862         smc_ib_buf_unmap_sg(lnk, buf_desc,
1863                             is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
1864 free_table:
1865         sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1866         return rc;
1867 }
1868
1869 /* register a new rmb on IB device,
1870  * must be called under lgr->llc_conf_mutex lock
1871  */
1872 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
1873 {
1874         if (list_empty(&link->lgr->list))
1875                 return -ENOLINK;
1876         if (!rmb_desc->is_reg_mr[link->link_idx]) {
1877                 /* register memory region for new rmb */
1878                 if (smc_wr_reg_send(link, rmb_desc->mr_rx[link->link_idx])) {
1879                         rmb_desc->is_reg_err = true;
1880                         return -EFAULT;
1881                 }
1882                 rmb_desc->is_reg_mr[link->link_idx] = true;
1883         }
1884         return 0;
1885 }
1886
1887 static int _smcr_buf_map_lgr(struct smc_link *lnk, struct mutex *lock,
1888                              struct list_head *lst, bool is_rmb)
1889 {
1890         struct smc_buf_desc *buf_desc, *bf;
1891         int rc = 0;
1892
1893         mutex_lock(lock);
1894         list_for_each_entry_safe(buf_desc, bf, lst, list) {
1895                 if (!buf_desc->used)
1896                         continue;
1897                 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
1898                 if (rc)
1899                         goto out;
1900         }
1901 out:
1902         mutex_unlock(lock);
1903         return rc;
1904 }
1905
1906 /* map all used buffers of lgr for a new link */
1907 int smcr_buf_map_lgr(struct smc_link *lnk)
1908 {
1909         struct smc_link_group *lgr = lnk->lgr;
1910         int i, rc = 0;
1911
1912         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1913                 rc = _smcr_buf_map_lgr(lnk, &lgr->rmbs_lock,
1914                                        &lgr->rmbs[i], true);
1915                 if (rc)
1916                         return rc;
1917                 rc = _smcr_buf_map_lgr(lnk, &lgr->sndbufs_lock,
1918                                        &lgr->sndbufs[i], false);
1919                 if (rc)
1920                         return rc;
1921         }
1922         return 0;
1923 }
1924
1925 /* register all used buffers of lgr for a new link,
1926  * must be called under lgr->llc_conf_mutex lock
1927  */
1928 int smcr_buf_reg_lgr(struct smc_link *lnk)
1929 {
1930         struct smc_link_group *lgr = lnk->lgr;
1931         struct smc_buf_desc *buf_desc, *bf;
1932         int i, rc = 0;
1933
1934         mutex_lock(&lgr->rmbs_lock);
1935         for (i = 0; i < SMC_RMBE_SIZES; i++) {
1936                 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
1937                         if (!buf_desc->used)
1938                                 continue;
1939                         rc = smcr_link_reg_rmb(lnk, buf_desc);
1940                         if (rc)
1941                                 goto out;
1942                 }
1943         }
1944 out:
1945         mutex_unlock(&lgr->rmbs_lock);
1946         return rc;
1947 }
1948
1949 static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
1950                                                 bool is_rmb, int bufsize)
1951 {
1952         struct smc_buf_desc *buf_desc;
1953
1954         /* try to alloc a new buffer */
1955         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
1956         if (!buf_desc)
1957                 return ERR_PTR(-ENOMEM);
1958
1959         buf_desc->order = get_order(bufsize);
1960         buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
1961                                       __GFP_NOMEMALLOC | __GFP_COMP |
1962                                       __GFP_NORETRY | __GFP_ZERO,
1963                                       buf_desc->order);
1964         if (!buf_desc->pages) {
1965                 kfree(buf_desc);
1966                 return ERR_PTR(-EAGAIN);
1967         }
1968         buf_desc->cpu_addr = (void *)page_address(buf_desc->pages);
1969         buf_desc->len = bufsize;
1970         return buf_desc;
1971 }
1972
1973 /* map buf_desc on all usable links,
1974  * unused buffers stay mapped as long as the link is up
1975  */
1976 static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
1977                                      struct smc_buf_desc *buf_desc, bool is_rmb)
1978 {
1979         int i, rc = 0;
1980
1981         /* protect against parallel link reconfiguration */
1982         mutex_lock(&lgr->llc_conf_mutex);
1983         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1984                 struct smc_link *lnk = &lgr->lnk[i];
1985
1986                 if (!smc_link_usable(lnk))
1987                         continue;
1988                 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
1989                         rc = -ENOMEM;
1990                         goto out;
1991                 }
1992         }
1993 out:
1994         mutex_unlock(&lgr->llc_conf_mutex);
1995         return rc;
1996 }
1997
1998 static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
1999                                                 bool is_dmb, int bufsize)
2000 {
2001         struct smc_buf_desc *buf_desc;
2002         int rc;
2003
2004         /* try to alloc a new DMB */
2005         buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
2006         if (!buf_desc)
2007                 return ERR_PTR(-ENOMEM);
2008         if (is_dmb) {
2009                 rc = smc_ism_register_dmb(lgr, bufsize, buf_desc);
2010                 if (rc) {
2011                         kfree(buf_desc);
2012                         if (rc == -ENOMEM)
2013                                 return ERR_PTR(-EAGAIN);
2014                         if (rc == -ENOSPC)
2015                                 return ERR_PTR(-ENOSPC);
2016                         return ERR_PTR(-EIO);
2017                 }
2018                 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2019                 /* CDC header stored in buf. So, pretend it was smaller */
2020                 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2021         } else {
2022                 buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
2023                                              __GFP_NOWARN | __GFP_NORETRY |
2024                                              __GFP_NOMEMALLOC);
2025                 if (!buf_desc->cpu_addr) {
2026                         kfree(buf_desc);
2027                         return ERR_PTR(-EAGAIN);
2028                 }
2029                 buf_desc->len = bufsize;
2030         }
2031         return buf_desc;
2032 }
2033
2034 static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2035 {
2036         struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
2037         struct smc_connection *conn = &smc->conn;
2038         struct smc_link_group *lgr = conn->lgr;
2039         struct list_head *buf_list;
2040         int bufsize, bufsize_short;
2041         bool is_dgraded = false;
2042         struct mutex *lock;     /* lock buffer list */
2043         int sk_buf_size;
2044
2045         if (is_rmb)
2046                 /* use socket recv buffer size (w/o overhead) as start value */
2047                 sk_buf_size = smc->sk.sk_rcvbuf / 2;
2048         else
2049                 /* use socket send buffer size (w/o overhead) as start value */
2050                 sk_buf_size = smc->sk.sk_sndbuf / 2;
2051
2052         for (bufsize_short = smc_compress_bufsize(sk_buf_size, is_smcd, is_rmb);
2053              bufsize_short >= 0; bufsize_short--) {
2054                 if (is_rmb) {
2055                         lock = &lgr->rmbs_lock;
2056                         buf_list = &lgr->rmbs[bufsize_short];
2057                 } else {
2058                         lock = &lgr->sndbufs_lock;
2059                         buf_list = &lgr->sndbufs[bufsize_short];
2060                 }
2061                 bufsize = smc_uncompress_bufsize(bufsize_short);
2062
2063                 /* check for reusable slot in the link group */
2064                 buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
2065                 if (buf_desc) {
2066                         SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2067                         SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2068                         memset(buf_desc->cpu_addr, 0, bufsize);
2069                         break; /* found reusable slot */
2070                 }
2071
2072                 if (is_smcd)
2073                         buf_desc = smcd_new_buf_create(lgr, is_rmb, bufsize);
2074                 else
2075                         buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
2076
2077                 if (PTR_ERR(buf_desc) == -ENOMEM)
2078                         break;
2079                 if (IS_ERR(buf_desc)) {
2080                         if (!is_dgraded) {
2081                                 is_dgraded = true;
2082                                 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2083                         }
2084                         continue;
2085                 }
2086
2087                 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2088                 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2089                 buf_desc->used = 1;
2090                 mutex_lock(lock);
2091                 list_add(&buf_desc->list, buf_list);
2092                 mutex_unlock(lock);
2093                 break; /* found */
2094         }
2095
2096         if (IS_ERR(buf_desc))
2097                 return PTR_ERR(buf_desc);
2098
2099         if (!is_smcd) {
2100                 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2101                         smcr_buf_unuse(buf_desc, lgr);
2102                         return -ENOMEM;
2103                 }
2104         }
2105
2106         if (is_rmb) {
2107                 conn->rmb_desc = buf_desc;
2108                 conn->rmbe_size_short = bufsize_short;
2109                 smc->sk.sk_rcvbuf = bufsize * 2;
2110                 atomic_set(&conn->bytes_to_rcv, 0);
2111                 conn->rmbe_update_limit =
2112                         smc_rmb_wnd_update_limit(buf_desc->len);
2113                 if (is_smcd)
2114                         smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2115         } else {
2116                 conn->sndbuf_desc = buf_desc;
2117                 smc->sk.sk_sndbuf = bufsize * 2;
2118                 atomic_set(&conn->sndbuf_space, bufsize);
2119         }
2120         return 0;
2121 }
2122
2123 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn)
2124 {
2125         if (!conn->lgr || conn->lgr->is_smcd || !smc_link_active(conn->lnk))
2126                 return;
2127         smc_ib_sync_sg_for_cpu(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2128 }
2129
2130 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2131 {
2132         if (!conn->lgr || conn->lgr->is_smcd || !smc_link_active(conn->lnk))
2133                 return;
2134         smc_ib_sync_sg_for_device(conn->lnk, conn->sndbuf_desc, DMA_TO_DEVICE);
2135 }
2136
2137 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2138 {
2139         int i;
2140
2141         if (!conn->lgr || conn->lgr->is_smcd)
2142                 return;
2143         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2144                 if (!smc_link_active(&conn->lgr->lnk[i]))
2145                         continue;
2146                 smc_ib_sync_sg_for_cpu(&conn->lgr->lnk[i], conn->rmb_desc,
2147                                        DMA_FROM_DEVICE);
2148         }
2149 }
2150
2151 void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
2152 {
2153         int i;
2154
2155         if (!conn->lgr || conn->lgr->is_smcd)
2156                 return;
2157         for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2158                 if (!smc_link_active(&conn->lgr->lnk[i]))
2159                         continue;
2160                 smc_ib_sync_sg_for_device(&conn->lgr->lnk[i], conn->rmb_desc,
2161                                           DMA_FROM_DEVICE);
2162         }
2163 }
2164
2165 /* create the send and receive buffer for an SMC socket;
2166  * receive buffers are called RMBs;
2167  * (even though the SMC protocol allows more than one RMB-element per RMB,
2168  * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2169  * extra RMB for every connection in a link group
2170  */
2171 int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2172 {
2173         int rc;
2174
2175         /* create send buffer */
2176         rc = __smc_buf_create(smc, is_smcd, false);
2177         if (rc)
2178                 return rc;
2179         /* create rmb */
2180         rc = __smc_buf_create(smc, is_smcd, true);
2181         if (rc) {
2182                 mutex_lock(&smc->conn.lgr->sndbufs_lock);
2183                 list_del(&smc->conn.sndbuf_desc->list);
2184                 mutex_unlock(&smc->conn.lgr->sndbufs_lock);
2185                 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
2186                 smc->conn.sndbuf_desc = NULL;
2187         }
2188         return rc;
2189 }
2190
2191 static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2192 {
2193         int i;
2194
2195         for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2196                 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
2197                         return i;
2198         }
2199         return -ENOSPC;
2200 }
2201
2202 static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2203                                    u32 rkey)
2204 {
2205         int i;
2206
2207         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2208                 if (test_bit(i, lgr->rtokens_used_mask) &&
2209                     lgr->rtokens[i][lnk_idx].rkey == rkey)
2210                         return i;
2211         }
2212         return -ENOENT;
2213 }
2214
2215 /* set rtoken for a new link to an existing rmb */
2216 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2217                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2218 {
2219         int rtok_idx;
2220
2221         rtok_idx = smc_rtoken_find_by_link(lgr, link_idx, ntohl(nw_rkey_known));
2222         if (rtok_idx == -ENOENT)
2223                 return;
2224         lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2225         lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2226 }
2227
2228 /* set rtoken for a new link whose link_id is given */
2229 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2230                      __be64 nw_vaddr, __be32 nw_rkey)
2231 {
2232         u64 dma_addr = be64_to_cpu(nw_vaddr);
2233         u32 rkey = ntohl(nw_rkey);
2234         bool found = false;
2235         int link_idx;
2236
2237         for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2238                 if (lgr->lnk[link_idx].link_id == link_id) {
2239                         found = true;
2240                         break;
2241                 }
2242         }
2243         if (!found)
2244                 return;
2245         lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2246         lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2247 }
2248
2249 /* add a new rtoken from peer */
2250 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2251 {
2252         struct smc_link_group *lgr = smc_get_lgr(lnk);
2253         u64 dma_addr = be64_to_cpu(nw_vaddr);
2254         u32 rkey = ntohl(nw_rkey);
2255         int i;
2256
2257         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2258                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2259                     lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2260                     test_bit(i, lgr->rtokens_used_mask)) {
2261                         /* already in list */
2262                         return i;
2263                 }
2264         }
2265         i = smc_rmb_reserve_rtoken_idx(lgr);
2266         if (i < 0)
2267                 return i;
2268         lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2269         lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2270         return i;
2271 }
2272
2273 /* delete an rtoken from all links */
2274 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2275 {
2276         struct smc_link_group *lgr = smc_get_lgr(lnk);
2277         u32 rkey = ntohl(nw_rkey);
2278         int i, j;
2279
2280         for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2281                 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2282                     test_bit(i, lgr->rtokens_used_mask)) {
2283                         for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2284                                 lgr->rtokens[i][j].rkey = 0;
2285                                 lgr->rtokens[i][j].dma_addr = 0;
2286                         }
2287                         clear_bit(i, lgr->rtokens_used_mask);
2288                         return 0;
2289                 }
2290         }
2291         return -ENOENT;
2292 }
2293
2294 /* save rkey and dma_addr received from peer during clc handshake */
2295 int smc_rmb_rtoken_handling(struct smc_connection *conn,
2296                             struct smc_link *lnk,
2297                             struct smc_clc_msg_accept_confirm *clc)
2298 {
2299         conn->rtoken_idx = smc_rtoken_add(lnk, clc->r0.rmb_dma_addr,
2300                                           clc->r0.rmb_rkey);
2301         if (conn->rtoken_idx < 0)
2302                 return conn->rtoken_idx;
2303         return 0;
2304 }
2305
2306 static void smc_core_going_away(void)
2307 {
2308         struct smc_ib_device *smcibdev;
2309         struct smcd_dev *smcd;
2310
2311         mutex_lock(&smc_ib_devices.mutex);
2312         list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2313                 int i;
2314
2315                 for (i = 0; i < SMC_MAX_PORTS; i++)
2316                         set_bit(i, smcibdev->ports_going_away);
2317         }
2318         mutex_unlock(&smc_ib_devices.mutex);
2319
2320         mutex_lock(&smcd_dev_list.mutex);
2321         list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2322                 smcd->going_away = 1;
2323         }
2324         mutex_unlock(&smcd_dev_list.mutex);
2325 }
2326
2327 /* Clean up all SMC link groups */
2328 static void smc_lgrs_shutdown(void)
2329 {
2330         struct smcd_dev *smcd;
2331
2332         smc_core_going_away();
2333
2334         smc_smcr_terminate_all(NULL);
2335
2336         mutex_lock(&smcd_dev_list.mutex);
2337         list_for_each_entry(smcd, &smcd_dev_list.list, list)
2338                 smc_smcd_terminate_all(smcd);
2339         mutex_unlock(&smcd_dev_list.mutex);
2340 }
2341
2342 static int smc_core_reboot_event(struct notifier_block *this,
2343                                  unsigned long event, void *ptr)
2344 {
2345         smc_lgrs_shutdown();
2346         smc_ib_unregister_client();
2347         return 0;
2348 }
2349
2350 static struct notifier_block smc_reboot_notifier = {
2351         .notifier_call = smc_core_reboot_event,
2352 };
2353
2354 int __init smc_core_init(void)
2355 {
2356         return register_reboot_notifier(&smc_reboot_notifier);
2357 }
2358
2359 /* Called (from smc_exit) when module is removed */
2360 void smc_core_exit(void)
2361 {
2362         unregister_reboot_notifier(&smc_reboot_notifier);
2363         smc_lgrs_shutdown();
2364 }