projects / linux-2.6-block.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Merge branch 'x86/pti' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
[linux-2.6-block.git] / net / smc / smc_core.c
CommitLineData
b2441318 1// SPDX-License-Identifier: GPL-2.0
0cfdd8f9
UB		 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 <net/tcp.h>
17#include <net/sock.h>
18#include <rdma/ib_verbs.h>
19
20#include "smc.h"
21#include "smc_clc.h"
22#include "smc_core.h"
23#include "smc_ib.h"
f38ba179 24#include "smc_wr.h"
9bf9abea 25#include "smc_llc.h"
5f08318f 26#include "smc_cdc.h"
b38d7324 27#include "smc_close.h"
0cfdd8f9 28
5bc11ddb
UB		 29#define SMC_LGR_NUM_INCR 256
30#define SMC_LGR_FREE_DELAY_SERV (600 * HZ)
7f58a1ad 31#define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
0cfdd8f9 32
9fda3510
HW		 33static struct smc_lgr_list smc_lgr_list = { /* established link groups */
34 .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
35 .list = LIST_HEAD_INIT(smc_lgr_list.list),
36 .num = 0,
37};
9bf9abea 38
6511aad3
HW		 39static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
40 struct smc_buf_desc *buf_desc);
a6920d1d 41
97cdbc42
KG		 42static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
43{
44 /* client link group creation always follows the server link group
45 * creation. For client use a somewhat higher removal delay time,
46 * otherwise there is a risk of out-of-sync link groups.
47 */
48 mod_delayed_work(system_wq, &lgr->free_work,
49 lgr->role == SMC_CLNT ? SMC_LGR_FREE_DELAY_CLNT :
50 SMC_LGR_FREE_DELAY_SERV);
51}
52
0cfdd8f9
UB		 53/* Register connection's alert token in our lookup structure.
54 * To use rbtrees we have to implement our own insert core.
55 * Requires @conns_lock
56 * @smc connection to register
57 * Returns 0 on success, != otherwise.
58 */
59static void smc_lgr_add_alert_token(struct smc_connection *conn)
60{
61 struct rb_node **link, *parent = NULL;
62 u32 token = conn->alert_token_local;
63
64 link = &conn->lgr->conns_all.rb_node;
65 while (*link) {
66 struct smc_connection *cur = rb_entry(*link,
67 struct smc_connection, alert_node);
68
69 parent = *link;
70 if (cur->alert_token_local > token)
71 link = &parent->rb_left;
72 else
73 link = &parent->rb_right;
74 }
75 /* Put the new node there */
76 rb_link_node(&conn->alert_node, parent, link);
77 rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
78}
79
80/* Register connection in link group by assigning an alert token
81 * registered in a search tree.
82 * Requires @conns_lock
83 * Note that '0' is a reserved value and not assigned.
84 */
85static void smc_lgr_register_conn(struct smc_connection *conn)
86{
87 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
88 static atomic_t nexttoken = ATOMIC_INIT(0);
89
90 /* find a new alert_token_local value not yet used by some connection
91 * in this link group
92 */
93 sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */
94 while (!conn->alert_token_local) {
95 conn->alert_token_local = atomic_inc_return(&nexttoken);
96 if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr))
97 conn->alert_token_local = 0;
98 }
99 smc_lgr_add_alert_token(conn);
100 conn->lgr->conns_num++;
101}
102
103/* Unregister connection and reset the alert token of the given connection<
104 */
105static void __smc_lgr_unregister_conn(struct smc_connection *conn)
106{
107 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
108 struct smc_link_group *lgr = conn->lgr;
109
110 rb_erase(&conn->alert_node, &lgr->conns_all);
111 lgr->conns_num--;
112 conn->alert_token_local = 0;
113 conn->lgr = NULL;
114 sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
115}
116
117/* Unregister connection and trigger lgr freeing if applicable
118 */
119static void smc_lgr_unregister_conn(struct smc_connection *conn)
120{
121 struct smc_link_group *lgr = conn->lgr;
122 int reduced = 0;
123
124 write_lock_bh(&lgr->conns_lock);
125 if (conn->alert_token_local) {
126 reduced = 1;
127 __smc_lgr_unregister_conn(conn);
128 }
129 write_unlock_bh(&lgr->conns_lock);
5bc11ddb
UB		 130 if (!reduced || lgr->conns_num)
131 return;
97cdbc42 132 smc_lgr_schedule_free_work(lgr);
0cfdd8f9
UB		 133}
134
135static void smc_lgr_free_work(struct work_struct *work)
136{
137 struct smc_link_group *lgr = container_of(to_delayed_work(work),
138 struct smc_link_group,
139 free_work);
140 bool conns;
141
142 spin_lock_bh(&smc_lgr_list.lock);
610db66f
UB		 143 if (list_empty(&lgr->list))
144 goto free;
0cfdd8f9
UB		 145 read_lock_bh(&lgr->conns_lock);
146 conns = RB_EMPTY_ROOT(&lgr->conns_all);
147 read_unlock_bh(&lgr->conns_lock);
148 if (!conns) { /* number of lgr connections is no longer zero */
149 spin_unlock_bh(&smc_lgr_list.lock);
150 return;
151 }
152 list_del_init(&lgr->list); /* remove from smc_lgr_list */
610db66f 153free:
0cfdd8f9 154 spin_unlock_bh(&smc_lgr_list.lock);
3cf52eb1
KG		 155 if (!delayed_work_pending(&lgr->free_work)) {
156 if (lgr->lnk[SMC_SINGLE_LINK].state != SMC_LNK_INACTIVE)
157 smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
268ffcc4 158 smc_lgr_free(lgr);
3cf52eb1 159 }
0cfdd8f9
UB		 160}
161
162/* create a new SMC link group */
be6d467b 163static int smc_lgr_create(struct smc_sock *smc,
0cfdd8f9
UB		 164 struct smc_ib_device *smcibdev, u8 ibport,
165 char *peer_systemid, unsigned short vlan_id)
166{
167 struct smc_link_group *lgr;
168 struct smc_link *lnk;
169 u8 rndvec[3];
170 int rc = 0;
cd6851f3 171 int i;
0cfdd8f9
UB		 172
173 lgr = kzalloc(sizeof(*lgr), GFP_KERNEL);
174 if (!lgr) {
175 rc = -ENOMEM;
176 goto out;
177 }
178 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
517c300e 179 lgr->sync_err = 0;
0cfdd8f9
UB		 180 memcpy(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN);
181 lgr->vlan_id = vlan_id;
cd6851f3
UB		 182 rwlock_init(&lgr->sndbufs_lock);
183 rwlock_init(&lgr->rmbs_lock);
184 for (i = 0; i < SMC_RMBE_SIZES; i++) {
185 INIT_LIST_HEAD(&lgr->sndbufs[i]);
186 INIT_LIST_HEAD(&lgr->rmbs[i]);
187 }
9fda3510
HW		 188 smc_lgr_list.num += SMC_LGR_NUM_INCR;
189 memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
0cfdd8f9
UB		 190 INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
191 lgr->conns_all = RB_ROOT;
192
193 lnk = &lgr->lnk[SMC_SINGLE_LINK];
194 /* initialize link */
52bedf37 195 lnk->state = SMC_LNK_ACTIVATING;
2be922f3 196 lnk->link_id = SMC_SINGLE_LINK;
0cfdd8f9
UB		 197 lnk->smcibdev = smcibdev;
198 lnk->ibport = ibport;
199 lnk->path_mtu = smcibdev->pattr[ibport - 1].active_mtu;
bd4ad577
UB		 200 if (!smcibdev->initialized)
201 smc_ib_setup_per_ibdev(smcibdev);
0cfdd8f9
UB		 202 get_random_bytes(rndvec, sizeof(rndvec));
203 lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + (rndvec[2] << 16);
2a4c57a9 204 rc = smc_llc_link_init(lnk);
f38ba179
UB		 205 if (rc)
206 goto free_lgr;
2a4c57a9
KG		 207 rc = smc_wr_alloc_link_mem(lnk);
208 if (rc)
209 goto clear_llc_lnk;
bd4ad577
UB		 210 rc = smc_ib_create_protection_domain(lnk);
211 if (rc)
212 goto free_link_mem;
213 rc = smc_ib_create_queue_pair(lnk);
214 if (rc)
215 goto dealloc_pd;
216 rc = smc_wr_create_link(lnk);
217 if (rc)
218 goto destroy_qp;
0cfdd8f9
UB		 219
220 smc->conn.lgr = lgr;
221 rwlock_init(&lgr->conns_lock);
222 spin_lock_bh(&smc_lgr_list.lock);
223 list_add(&lgr->list, &smc_lgr_list.list);
224 spin_unlock_bh(&smc_lgr_list.lock);
f38ba179
UB		 225 return 0;
226
bd4ad577
UB		 227destroy_qp:
228 smc_ib_destroy_queue_pair(lnk);
229dealloc_pd:
230 smc_ib_dealloc_protection_domain(lnk);
231free_link_mem:
232 smc_wr_free_link_mem(lnk);
2a4c57a9
KG		 233clear_llc_lnk:
234 smc_llc_link_clear(lnk);
f38ba179
UB		 235free_lgr:
236 kfree(lgr);
0cfdd8f9
UB		 237out:
238 return rc;
239}
240
3e034725 241static void smc_buf_unuse(struct smc_connection *conn)
cd6851f3 242{
69cb7dc0 243 if (conn->sndbuf_desc)
cd6851f3 244 conn->sndbuf_desc->used = 0;
cd6851f3 245 if (conn->rmb_desc) {
a6920d1d
KG		 246 if (!conn->rmb_desc->regerr) {
247 conn->rmb_desc->reused = 1;
248 conn->rmb_desc->used = 0;
a6920d1d
KG		 249 } else {
250 /* buf registration failed, reuse not possible */
251 struct smc_link_group *lgr = conn->lgr;
a6920d1d
KG		 252
253 write_lock_bh(&lgr->rmbs_lock);
254 list_del(&conn->rmb_desc->list);
255 write_unlock_bh(&lgr->rmbs_lock);
256
6511aad3 257 smc_buf_free(lgr, true, conn->rmb_desc);
a6920d1d 258 }
cd6851f3
UB		 259 }
260}
261
0cfdd8f9
UB		 262/* remove a finished connection from its link group */
263void smc_conn_free(struct smc_connection *conn)
264{
732720fa 265 if (!conn->lgr)
0cfdd8f9 266 return;
5f08318f 267 smc_cdc_tx_dismiss_slots(conn);
0cfdd8f9 268 smc_lgr_unregister_conn(conn);
3e034725 269 smc_buf_unuse(conn);
0cfdd8f9
UB		 270}
271
272static void smc_link_clear(struct smc_link *lnk)
273{
274 lnk->peer_qpn = 0;
2a4c57a9 275 smc_llc_link_clear(lnk);
bd4ad577 276 smc_ib_modify_qp_reset(lnk);
f38ba179 277 smc_wr_free_link(lnk);
bd4ad577
UB		 278 smc_ib_destroy_queue_pair(lnk);
279 smc_ib_dealloc_protection_domain(lnk);
f38ba179 280 smc_wr_free_link_mem(lnk);
0cfdd8f9
UB		 281}
282
6511aad3
HW		 283static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
284 struct smc_buf_desc *buf_desc)
cd6851f3 285{
6511aad3
HW		 286 struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
287
3e034725
UB		 288 if (is_rmb) {
289 if (buf_desc->mr_rx[SMC_SINGLE_LINK])
290 smc_ib_put_memory_region(
291 buf_desc->mr_rx[SMC_SINGLE_LINK]);
292 smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc,
293 DMA_FROM_DEVICE);
294 } else {
295 smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc,
296 DMA_TO_DEVICE);
cd6851f3 297 }
3e034725 298 sg_free_table(&buf_desc->sgt[SMC_SINGLE_LINK]);
2ef4f27a
SR		 299 if (buf_desc->pages)
300 __free_pages(buf_desc->pages, buf_desc->order);
3e034725 301 kfree(buf_desc);
cd6851f3
UB		 302}
303
3e034725 304static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
cd6851f3 305{
3e034725
UB		 306 struct smc_buf_desc *buf_desc, *bf_desc;
307 struct list_head *buf_list;
cd6851f3
UB		 308 int i;
309
310 for (i = 0; i < SMC_RMBE_SIZES; i++) {
3e034725
UB		 311 if (is_rmb)
312 buf_list = &lgr->rmbs[i];
313 else
314 buf_list = &lgr->sndbufs[i];
315 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
cd6851f3 316 list) {
3e034725 317 list_del(&buf_desc->list);
6511aad3 318 smc_buf_free(lgr, is_rmb, buf_desc);
cd6851f3
UB		 319 }
320 }
321}
322
3e034725
UB		 323static void smc_lgr_free_bufs(struct smc_link_group *lgr)
324{
325 /* free send buffers */
326 __smc_lgr_free_bufs(lgr, false);
327 /* free rmbs */
328 __smc_lgr_free_bufs(lgr, true);
329}
330
0cfdd8f9
UB		 331/* remove a link group */
332void smc_lgr_free(struct smc_link_group *lgr)
333{
3e034725 334 smc_lgr_free_bufs(lgr);
0cfdd8f9
UB		 335 smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]);
336 kfree(lgr);
337}
338
9651b934
KG		 339void smc_lgr_forget(struct smc_link_group *lgr)
340{
341 spin_lock_bh(&smc_lgr_list.lock);
342 /* do not use this link group for new connections */
343 if (!list_empty(&lgr->list))
344 list_del_init(&lgr->list);
345 spin_unlock_bh(&smc_lgr_list.lock);
346}
347
0cfdd8f9 348/* terminate linkgroup abnormally */
b9f227c3 349static void __smc_lgr_terminate(struct smc_link_group *lgr)
0cfdd8f9
UB		 350{
351 struct smc_connection *conn;
b38d7324 352 struct smc_sock *smc;
0cfdd8f9
UB		 353 struct rb_node *node;
354
517c300e
KG		 355 if (lgr->terminating)
356 return; /* lgr already terminating */
357 lgr->terminating = 1;
b9f227c3
HW		 358 if (!list_empty(&lgr->list)) /* forget lgr */
359 list_del_init(&lgr->list);
877ae5be 360 smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
0cfdd8f9
UB		 361
362 write_lock_bh(&lgr->conns_lock);
363 node = rb_first(&lgr->conns_all);
364 while (node) {
365 conn = rb_entry(node, struct smc_connection, alert_node);
b38d7324 366 smc = container_of(conn, struct smc_sock, conn);
51f1de79 367 sock_hold(&smc->sk); /* sock_put in close work */
732720fa 368 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
0cfdd8f9 369 __smc_lgr_unregister_conn(conn);
732720fa 370 write_unlock_bh(&lgr->conns_lock);
51f1de79
UB		 371 if (!schedule_work(&conn->close_work))
372 sock_put(&smc->sk);
732720fa 373 write_lock_bh(&lgr->conns_lock);
0cfdd8f9
UB		 374 node = rb_first(&lgr->conns_all);
375 }
376 write_unlock_bh(&lgr->conns_lock);
732720fa 377 wake_up(&lgr->lnk[SMC_SINGLE_LINK].wr_reg_wait);
97cdbc42 378 smc_lgr_schedule_free_work(lgr);
0cfdd8f9
UB		 379}
380
b9f227c3
HW		 381void smc_lgr_terminate(struct smc_link_group *lgr)
382{
383 spin_lock_bh(&smc_lgr_list.lock);
384 __smc_lgr_terminate(lgr);
385 spin_unlock_bh(&smc_lgr_list.lock);
386}
387
9fda3510
HW		 388/* Called when IB port is terminated */
389void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport)
390{
391 struct smc_link_group *lgr, *l;
392
b9f227c3 393 spin_lock_bh(&smc_lgr_list.lock);
9fda3510
HW		 394 list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) {
395 if (lgr->lnk[SMC_SINGLE_LINK].smcibdev == smcibdev &&
396 lgr->lnk[SMC_SINGLE_LINK].ibport == ibport)
b9f227c3 397 __smc_lgr_terminate(lgr);
9fda3510 398 }
b9f227c3 399 spin_unlock_bh(&smc_lgr_list.lock);
9fda3510
HW		 400}
401
0cfdd8f9
UB		 402/* Determine vlan of internal TCP socket.
403 * @vlan_id: address to store the determined vlan id into
404 */
405static int smc_vlan_by_tcpsk(struct socket *clcsock, unsigned short *vlan_id)
406{
407 struct dst_entry *dst = sk_dst_get(clcsock->sk);
cb9d43f6
UB		 408 struct net_device *ndev;
409 int i, nest_lvl, rc = 0;
0cfdd8f9
UB		 410
411 *vlan_id = 0;
412 if (!dst) {
413 rc = -ENOTCONN;
414 goto out;
415 }
416 if (!dst->dev) {
417 rc = -ENODEV;
418 goto out_rel;
419 }
420
cb9d43f6
UB		 421 ndev = dst->dev;
422 if (is_vlan_dev(ndev)) {
423 *vlan_id = vlan_dev_vlan_id(ndev);
424 goto out_rel;
425 }
426
427 rtnl_lock();
428 nest_lvl = dev_get_nest_level(ndev);
429 for (i = 0; i < nest_lvl; i++) {
430 struct list_head *lower = &ndev->adj_list.lower;
431
432 if (list_empty(lower))
433 break;
434 lower = lower->next;
435 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
436 if (is_vlan_dev(ndev)) {
437 *vlan_id = vlan_dev_vlan_id(ndev);
438 break;
439 }
440 }
441 rtnl_unlock();
0cfdd8f9
UB		 442
443out_rel:
444 dst_release(dst);
445out:
446 return rc;
447}
448
449/* determine the link gid matching the vlan id of the link group */
450static int smc_link_determine_gid(struct smc_link_group *lgr)
451{
452 struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK];
453 struct ib_gid_attr gattr;
454 union ib_gid gid;
455 int i;
456
457 if (!lgr->vlan_id) {
458 lnk->gid = lnk->smcibdev->gid[lnk->ibport - 1];
459 return 0;
460 }
461
462 for (i = 0; i < lnk->smcibdev->pattr[lnk->ibport - 1].gid_tbl_len;
463 i++) {
464 if (ib_query_gid(lnk->smcibdev->ibdev, lnk->ibport, i, &gid,
465 &gattr))
466 continue;
43e2ada3
UB		 467 if (gattr.ndev) {
468 if (is_vlan_dev(gattr.ndev) &&
469 vlan_dev_vlan_id(gattr.ndev) == lgr->vlan_id) {
470 lnk->gid = gid;
471 dev_put(gattr.ndev);
472 return 0;
473 }
474 dev_put(gattr.ndev);
0cfdd8f9
UB		 475 }
476 }
477 return -ENODEV;
478}
479
480/* create a new SMC connection (and a new link group if necessary) */
be6d467b 481int smc_conn_create(struct smc_sock *smc,
0cfdd8f9
UB		 482 struct smc_ib_device *smcibdev, u8 ibport,
483 struct smc_clc_msg_local *lcl, int srv_first_contact)
484{
485 struct smc_connection *conn = &smc->conn;
8437bda0 486 int local_contact = SMC_FIRST_CONTACT;
0cfdd8f9
UB		 487 struct smc_link_group *lgr;
488 unsigned short vlan_id;
489 enum smc_lgr_role role;
0cfdd8f9
UB		 490 int rc = 0;
491
492 role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
493 rc = smc_vlan_by_tcpsk(smc->clcsock, &vlan_id);
494 if (rc)
495 return rc;
496
497 if ((role == SMC_CLNT) && srv_first_contact)
498 /* create new link group as well */
499 goto create;
500
501 /* determine if an existing link group can be reused */
502 spin_lock_bh(&smc_lgr_list.lock);
503 list_for_each_entry(lgr, &smc_lgr_list.list, list) {
504 write_lock_bh(&lgr->conns_lock);
505 if (!memcmp(lgr->peer_systemid, lcl->id_for_peer,
506 SMC_SYSTEMID_LEN) &&
507 !memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_gid, &lcl->gid,
508 SMC_GID_SIZE) &&
509 !memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_mac, lcl->mac,
510 sizeof(lcl->mac)) &&
511 !lgr->sync_err &&
512 (lgr->role == role) &&
cd6851f3
UB		 513 (lgr->vlan_id == vlan_id) &&
514 ((role == SMC_CLNT) ||
515 (lgr->conns_num < SMC_RMBS_PER_LGR_MAX))) {
0cfdd8f9
UB		 516 /* link group found */
517 local_contact = SMC_REUSE_CONTACT;
518 conn->lgr = lgr;
519 smc_lgr_register_conn(conn); /* add smc conn to lgr */
520 write_unlock_bh(&lgr->conns_lock);
521 break;
522 }
523 write_unlock_bh(&lgr->conns_lock);
524 }
525 spin_unlock_bh(&smc_lgr_list.lock);
526
527 if (role == SMC_CLNT && !srv_first_contact &&
528 (local_contact == SMC_FIRST_CONTACT)) {
529 /* Server reuses a link group, but Client wants to start
530 * a new one
531 * send out_of_sync decline, reason synchr. error
532 */
533 return -ENOLINK;
534 }
535
536create:
537 if (local_contact == SMC_FIRST_CONTACT) {
be6d467b 538 rc = smc_lgr_create(smc, smcibdev, ibport,
0cfdd8f9
UB		 539 lcl->id_for_peer, vlan_id);
540 if (rc)
541 goto out;
542 smc_lgr_register_conn(conn); /* add smc conn to lgr */
543 rc = smc_link_determine_gid(conn->lgr);
544 }
5f08318f 545 conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
cbba07a7 546 conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
de8474eb 547 conn->urg_state = SMC_URG_READ;
5f08318f
UB		 548#ifndef KERNEL_HAS_ATOMIC64
549 spin_lock_init(&conn->acurs_lock);
550#endif
0cfdd8f9
UB		 551
552out:
553 return rc ? rc : local_contact;
554}
cd6851f3 555
2f6becaf
HW		 556/* convert the RMB size into the compressed notation - minimum 16K.
557 * In contrast to plain ilog2, this rounds towards the next power of 2,
558 * so the socket application gets at least its desired sndbuf / rcvbuf size.
559 */
560static u8 smc_compress_bufsize(int size)
561{
562 u8 compressed;
563
564 if (size <= SMC_BUF_MIN_SIZE)
565 return 0;
566
567 size = (size - 1) >> 14;
568 compressed = ilog2(size) + 1;
569 if (compressed >= SMC_RMBE_SIZES)
570 compressed = SMC_RMBE_SIZES - 1;
571 return compressed;
572}
573
574/* convert the RMB size from compressed notation into integer */
575int smc_uncompress_bufsize(u8 compressed)
576{
577 u32 size;
578
579 size = 0x00000001 << (((int)compressed) + 14);
580 return (int)size;
581}
582
3e034725
UB		 583/* try to reuse a sndbuf or rmb description slot for a certain
584 * buffer size; if not available, return NULL
cd6851f3 585 */
8437bda0
HW		 586static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
587 rwlock_t *lock,
588 struct list_head *buf_list)
cd6851f3 589{
3e034725 590 struct smc_buf_desc *buf_slot;
cd6851f3 591
3e034725
UB		 592 read_lock_bh(lock);
593 list_for_each_entry(buf_slot, buf_list, list) {
594 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
595 read_unlock_bh(lock);
596 return buf_slot;
cd6851f3
UB		 597 }
598 }
3e034725 599 read_unlock_bh(lock);
cd6851f3
UB		 600 return NULL;
601}
602
952310cc
UB		 603/* one of the conditions for announcing a receiver's current window size is
604 * that it "results in a minimum increase in the window size of 10% of the
605 * receive buffer space" [RFC7609]
606 */
607static inline int smc_rmb_wnd_update_limit(int rmbe_size)
608{
609 return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
610}
611
b33982c3
UB		 612static struct smc_buf_desc *smc_new_buf_create(struct smc_link_group *lgr,
613 bool is_rmb, int bufsize)
614{
615 struct smc_buf_desc *buf_desc;
616 struct smc_link *lnk;
617 int rc;
618
619 /* try to alloc a new buffer */
620 buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL);
621 if (!buf_desc)
622 return ERR_PTR(-ENOMEM);
623
2ef4f27a
SR		 624 buf_desc->order = get_order(bufsize);
625 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
626 __GFP_NOMEMALLOC | __GFP_COMP |
627 __GFP_NORETRY | __GFP_ZERO,
628 buf_desc->order);
629 if (!buf_desc->pages) {
b33982c3
UB		 630 kfree(buf_desc);
631 return ERR_PTR(-EAGAIN);
632 }
2ef4f27a 633 buf_desc->cpu_addr = (void *)page_address(buf_desc->pages);
b33982c3
UB		 634
635 /* build the sg table from the pages */
636 lnk = &lgr->lnk[SMC_SINGLE_LINK];
637 rc = sg_alloc_table(&buf_desc->sgt[SMC_SINGLE_LINK], 1,
638 GFP_KERNEL);
639 if (rc) {
6511aad3 640 smc_buf_free(lgr, is_rmb, buf_desc);
b33982c3
UB		 641 return ERR_PTR(rc);
642 }
643 sg_set_buf(buf_desc->sgt[SMC_SINGLE_LINK].sgl,
644 buf_desc->cpu_addr, bufsize);
645
646 /* map sg table to DMA address */
647 rc = smc_ib_buf_map_sg(lnk->smcibdev, buf_desc,
648 is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
649 /* SMC protocol depends on mapping to one DMA address only */
650 if (rc != 1) {
6511aad3 651 smc_buf_free(lgr, is_rmb, buf_desc);
b33982c3
UB		 652 return ERR_PTR(-EAGAIN);
653 }
654
655 /* create a new memory region for the RMB */
656 if (is_rmb) {
657 rc = smc_ib_get_memory_region(lnk->roce_pd,
658 IB_ACCESS_REMOTE_WRITE |
659 IB_ACCESS_LOCAL_WRITE,
660 buf_desc);
661 if (rc) {
6511aad3 662 smc_buf_free(lgr, is_rmb, buf_desc);
b33982c3
UB		 663 return ERR_PTR(rc);
664 }
665 }
666
69cb7dc0 667 buf_desc->len = bufsize;
b33982c3
UB		 668 return buf_desc;
669}
670
3e034725 671static int __smc_buf_create(struct smc_sock *smc, bool is_rmb)
cd6851f3 672{
8437bda0 673 struct smc_buf_desc *buf_desc = ERR_PTR(-ENOMEM);
cd6851f3
UB		 674 struct smc_connection *conn = &smc->conn;
675 struct smc_link_group *lgr = conn->lgr;
3e034725 676 struct list_head *buf_list;
c45abf31 677 int bufsize, bufsize_short;
3e034725
UB		 678 int sk_buf_size;
679 rwlock_t *lock;
cd6851f3 680
3e034725
UB		 681 if (is_rmb)
682 /* use socket recv buffer size (w/o overhead) as start value */
683 sk_buf_size = smc->sk.sk_rcvbuf / 2;
684 else
685 /* use socket send buffer size (w/o overhead) as start value */
686 sk_buf_size = smc->sk.sk_sndbuf / 2;
687
4e1061f4 688 for (bufsize_short = smc_compress_bufsize(sk_buf_size);
c45abf31 689 bufsize_short >= 0; bufsize_short--) {
9d8fb617 690
3e034725
UB		 691 if (is_rmb) {
692 lock = &lgr->rmbs_lock;
693 buf_list = &lgr->rmbs[bufsize_short];
694 } else {
695 lock = &lgr->sndbufs_lock;
696 buf_list = &lgr->sndbufs[bufsize_short];
9d8fb617 697 }
c45abf31 698 bufsize = smc_uncompress_bufsize(bufsize_short);
a3fe3d01
UB		 699 if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC)
700 continue;
701
3e034725 702 /* check for reusable slot in the link group */
8437bda0 703 buf_desc = smc_buf_get_slot(bufsize_short, lock, buf_list);
3e034725
UB		 704 if (buf_desc) {
705 memset(buf_desc->cpu_addr, 0, bufsize);
cd6851f3
UB		 706 break; /* found reusable slot */
707 }
a3fe3d01 708
b33982c3
UB		 709 buf_desc = smc_new_buf_create(lgr, is_rmb, bufsize);
710 if (PTR_ERR(buf_desc) == -ENOMEM)
711 break;
712 if (IS_ERR(buf_desc))
a3fe3d01 713 continue;
897e1c24 714
3e034725
UB		 715 buf_desc->used = 1;
716 write_lock_bh(lock);
717 list_add(&buf_desc->list, buf_list);
718 write_unlock_bh(lock);
719 break; /* found */
cd6851f3 720 }
3e034725 721
b33982c3 722 if (IS_ERR(buf_desc))
3e034725
UB		 723 return -ENOMEM;
724
725 if (is_rmb) {
726 conn->rmb_desc = buf_desc;
c45abf31
UB		 727 conn->rmbe_size_short = bufsize_short;
728 smc->sk.sk_rcvbuf = bufsize * 2;
5f08318f 729 atomic_set(&conn->bytes_to_rcv, 0);
c45abf31 730 conn->rmbe_update_limit = smc_rmb_wnd_update_limit(bufsize);
cd6851f3 731 } else {
3e034725 732 conn->sndbuf_desc = buf_desc;
3e034725
UB		 733 smc->sk.sk_sndbuf = bufsize * 2;
734 atomic_set(&conn->sndbuf_space, bufsize);
cd6851f3 735 }
3e034725
UB		 736 return 0;
737}
738
10428dd8
UB		 739void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn)
740{
741 struct smc_link_group *lgr = conn->lgr;
742
743 smc_ib_sync_sg_for_cpu(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
744 conn->sndbuf_desc, DMA_TO_DEVICE);
745}
746
747void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
748{
749 struct smc_link_group *lgr = conn->lgr;
750
751 smc_ib_sync_sg_for_device(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
752 conn->sndbuf_desc, DMA_TO_DEVICE);
753}
754
755void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
756{
757 struct smc_link_group *lgr = conn->lgr;
758
759 smc_ib_sync_sg_for_cpu(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
760 conn->rmb_desc, DMA_FROM_DEVICE);
761}
762
763void smc_rmb_sync_sg_for_device(struct smc_connection *conn)
764{
765 struct smc_link_group *lgr = conn->lgr;
766
767 smc_ib_sync_sg_for_device(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
768 conn->rmb_desc, DMA_FROM_DEVICE);
769}
770
3e034725
UB		 771/* create the send and receive buffer for an SMC socket;
772 * receive buffers are called RMBs;
773 * (even though the SMC protocol allows more than one RMB-element per RMB,
774 * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
775 * extra RMB for every connection in a link group
776 */
777int smc_buf_create(struct smc_sock *smc)
778{
779 int rc;
780
781 /* create send buffer */
782 rc = __smc_buf_create(smc, false);
783 if (rc)
784 return rc;
785 /* create rmb */
786 rc = __smc_buf_create(smc, true);
787 if (rc)
6511aad3 788 smc_buf_free(smc->conn.lgr, false, smc->conn.sndbuf_desc);
3e034725 789 return rc;
cd6851f3 790}
bd4ad577
UB		 791
792static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
793{
794 int i;
795
796 for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
797 if (!test_and_set_bit(i, lgr->rtokens_used_mask))
798 return i;
799 }
800 return -ENOSPC;
801}
802
4ed75de5
KG		 803/* add a new rtoken from peer */
804int smc_rtoken_add(struct smc_link_group *lgr, __be64 nw_vaddr, __be32 nw_rkey)
bd4ad577 805{
4ed75de5
KG		 806 u64 dma_addr = be64_to_cpu(nw_vaddr);
807 u32 rkey = ntohl(nw_rkey);
bd4ad577
UB		 808 int i;
809
810 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
811 if ((lgr->rtokens[i][SMC_SINGLE_LINK].rkey == rkey) &&
263eec9b 812 (lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr == dma_addr) &&
bd4ad577 813 test_bit(i, lgr->rtokens_used_mask)) {
4ed75de5
KG		 814 /* already in list */
815 return i;
816 }
817 }
818 i = smc_rmb_reserve_rtoken_idx(lgr);
819 if (i < 0)
820 return i;
821 lgr->rtokens[i][SMC_SINGLE_LINK].rkey = rkey;
822 lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr = dma_addr;
823 return i;
824}
825
826/* delete an rtoken */
827int smc_rtoken_delete(struct smc_link_group *lgr, __be32 nw_rkey)
828{
829 u32 rkey = ntohl(nw_rkey);
830 int i;
831
832 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
833 if (lgr->rtokens[i][SMC_SINGLE_LINK].rkey == rkey &&
834 test_bit(i, lgr->rtokens_used_mask)) {
835 lgr->rtokens[i][SMC_SINGLE_LINK].rkey = 0;
836 lgr->rtokens[i][SMC_SINGLE_LINK].dma_addr = 0;
837
838 clear_bit(i, lgr->rtokens_used_mask);
bd4ad577
UB		 839 return 0;
840 }
841 }
4ed75de5
KG		 842 return -ENOENT;
843}
844
845/* save rkey and dma_addr received from peer during clc handshake */
846int smc_rmb_rtoken_handling(struct smc_connection *conn,
847 struct smc_clc_msg_accept_confirm *clc)
848{
849 conn->rtoken_idx = smc_rtoken_add(conn->lgr, clc->rmb_dma_addr,
850 clc->rmb_rkey);
bd4ad577
UB		 851 if (conn->rtoken_idx < 0)
852 return conn->rtoken_idx;
bd4ad577
UB		 853 return 0;
854}
9fda3510
HW		 855
856/* Called (from smc_exit) when module is removed */
857void smc_core_exit(void)
858{
859 struct smc_link_group *lgr, *lg;
860 LIST_HEAD(lgr_freeing_list);
861
862 spin_lock_bh(&smc_lgr_list.lock);
863 if (!list_empty(&smc_lgr_list.list))
864 list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
865 spin_unlock_bh(&smc_lgr_list.lock);
866 list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
867 list_del_init(&lgr->list);
868 smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
869 cancel_delayed_work_sync(&lgr->free_work);
870 smc_lgr_free(lgr); /* free link group */
871 }
872}
Linux 6.x block layer and io_uring tree(s)