Loading...
Note: File does not exist in v3.1.
1// SPDX-License-Identifier: GPL-2.0
2/* Shared Memory Communications Direct over ISM devices (SMC-D)
3 *
4 * Functions for ISM device.
5 *
6 * Copyright IBM Corp. 2018
7 */
8
9#include <linux/if_vlan.h>
10#include <linux/spinlock.h>
11#include <linux/mutex.h>
12#include <linux/slab.h>
13#include <asm/page.h>
14
15#include "smc.h"
16#include "smc_core.h"
17#include "smc_ism.h"
18#include "smc_pnet.h"
19#include "smc_netlink.h"
20
21struct smcd_dev_list smcd_dev_list = {
22 .list = LIST_HEAD_INIT(smcd_dev_list.list),
23 .mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex)
24};
25
26static bool smc_ism_v2_capable;
27static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN];
28
29/* Test if an ISM communication is possible - same CPC */
30int smc_ism_cantalk(u64 peer_gid, unsigned short vlan_id, struct smcd_dev *smcd)
31{
32 return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0,
33 vlan_id);
34}
35
36void smc_ism_get_system_eid(u8 **eid)
37{
38 if (!smc_ism_v2_capable)
39 *eid = NULL;
40 else
41 *eid = smc_ism_v2_system_eid;
42}
43
44u16 smc_ism_get_chid(struct smcd_dev *smcd)
45{
46 return smcd->ops->get_chid(smcd);
47}
48
49/* HW supports ISM V2 and thus System EID is defined */
50bool smc_ism_is_v2_capable(void)
51{
52 return smc_ism_v2_capable;
53}
54
55/* Set a connection using this DMBE. */
56void smc_ism_set_conn(struct smc_connection *conn)
57{
58 unsigned long flags;
59
60 spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
61 conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn;
62 spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
63}
64
65/* Unset a connection using this DMBE. */
66void smc_ism_unset_conn(struct smc_connection *conn)
67{
68 unsigned long flags;
69
70 if (!conn->rmb_desc)
71 return;
72
73 spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
74 conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL;
75 spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
76}
77
78/* Register a VLAN identifier with the ISM device. Use a reference count
79 * and add a VLAN identifier only when the first DMB using this VLAN is
80 * registered.
81 */
82int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
83{
84 struct smc_ism_vlanid *new_vlan, *vlan;
85 unsigned long flags;
86 int rc = 0;
87
88 if (!vlanid) /* No valid vlan id */
89 return -EINVAL;
90
91 /* create new vlan entry, in case we need it */
92 new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL);
93 if (!new_vlan)
94 return -ENOMEM;
95 new_vlan->vlanid = vlanid;
96 refcount_set(&new_vlan->refcnt, 1);
97
98 /* if there is an existing entry, increase count and return */
99 spin_lock_irqsave(&smcd->lock, flags);
100 list_for_each_entry(vlan, &smcd->vlan, list) {
101 if (vlan->vlanid == vlanid) {
102 refcount_inc(&vlan->refcnt);
103 kfree(new_vlan);
104 goto out;
105 }
106 }
107
108 /* no existing entry found.
109 * add new entry to device; might fail, e.g., if HW limit reached
110 */
111 if (smcd->ops->add_vlan_id(smcd, vlanid)) {
112 kfree(new_vlan);
113 rc = -EIO;
114 goto out;
115 }
116 list_add_tail(&new_vlan->list, &smcd->vlan);
117out:
118 spin_unlock_irqrestore(&smcd->lock, flags);
119 return rc;
120}
121
122/* Unregister a VLAN identifier with the ISM device. Use a reference count
123 * and remove a VLAN identifier only when the last DMB using this VLAN is
124 * unregistered.
125 */
126int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
127{
128 struct smc_ism_vlanid *vlan;
129 unsigned long flags;
130 bool found = false;
131 int rc = 0;
132
133 if (!vlanid) /* No valid vlan id */
134 return -EINVAL;
135
136 spin_lock_irqsave(&smcd->lock, flags);
137 list_for_each_entry(vlan, &smcd->vlan, list) {
138 if (vlan->vlanid == vlanid) {
139 if (!refcount_dec_and_test(&vlan->refcnt))
140 goto out;
141 found = true;
142 break;
143 }
144 }
145 if (!found) {
146 rc = -ENOENT;
147 goto out; /* VLAN id not in table */
148 }
149
150 /* Found and the last reference just gone */
151 if (smcd->ops->del_vlan_id(smcd, vlanid))
152 rc = -EIO;
153 list_del(&vlan->list);
154 kfree(vlan);
155out:
156 spin_unlock_irqrestore(&smcd->lock, flags);
157 return rc;
158}
159
160int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc)
161{
162 struct smcd_dmb dmb;
163 int rc = 0;
164
165 if (!dmb_desc->dma_addr)
166 return rc;
167
168 memset(&dmb, 0, sizeof(dmb));
169 dmb.dmb_tok = dmb_desc->token;
170 dmb.sba_idx = dmb_desc->sba_idx;
171 dmb.cpu_addr = dmb_desc->cpu_addr;
172 dmb.dma_addr = dmb_desc->dma_addr;
173 dmb.dmb_len = dmb_desc->len;
174 rc = smcd->ops->unregister_dmb(smcd, &dmb);
175 if (!rc || rc == ISM_ERROR) {
176 dmb_desc->cpu_addr = NULL;
177 dmb_desc->dma_addr = 0;
178 }
179
180 return rc;
181}
182
183int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
184 struct smc_buf_desc *dmb_desc)
185{
186 struct smcd_dmb dmb;
187 int rc;
188
189 memset(&dmb, 0, sizeof(dmb));
190 dmb.dmb_len = dmb_len;
191 dmb.sba_idx = dmb_desc->sba_idx;
192 dmb.vlan_id = lgr->vlan_id;
193 dmb.rgid = lgr->peer_gid;
194 rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb);
195 if (!rc) {
196 dmb_desc->sba_idx = dmb.sba_idx;
197 dmb_desc->token = dmb.dmb_tok;
198 dmb_desc->cpu_addr = dmb.cpu_addr;
199 dmb_desc->dma_addr = dmb.dma_addr;
200 dmb_desc->len = dmb.dmb_len;
201 }
202 return rc;
203}
204
205static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd,
206 struct sk_buff *skb,
207 struct netlink_callback *cb)
208{
209 char smc_pnet[SMC_MAX_PNETID_LEN + 1];
210 struct smc_pci_dev smc_pci_dev;
211 struct nlattr *port_attrs;
212 struct nlattr *attrs;
213 int use_cnt = 0;
214 void *nlh;
215
216 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
217 &smc_gen_nl_family, NLM_F_MULTI,
218 SMC_NETLINK_GET_DEV_SMCD);
219 if (!nlh)
220 goto errmsg;
221 attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD);
222 if (!attrs)
223 goto errout;
224 use_cnt = atomic_read(&smcd->lgr_cnt);
225 if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt))
226 goto errattr;
227 if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0))
228 goto errattr;
229 memset(&smc_pci_dev, 0, sizeof(smc_pci_dev));
230 smc_set_pci_values(to_pci_dev(smcd->dev.parent), &smc_pci_dev);
231 if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid))
232 goto errattr;
233 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid))
234 goto errattr;
235 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor))
236 goto errattr;
237 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device))
238 goto errattr;
239 if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id))
240 goto errattr;
241
242 port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT);
243 if (!port_attrs)
244 goto errattr;
245 if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user))
246 goto errportattr;
247 memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN);
248 smc_pnet[SMC_MAX_PNETID_LEN] = 0;
249 if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet))
250 goto errportattr;
251
252 nla_nest_end(skb, port_attrs);
253 nla_nest_end(skb, attrs);
254 genlmsg_end(skb, nlh);
255 return 0;
256
257errportattr:
258 nla_nest_cancel(skb, port_attrs);
259errattr:
260 nla_nest_cancel(skb, attrs);
261errout:
262 nlmsg_cancel(skb, nlh);
263errmsg:
264 return -EMSGSIZE;
265}
266
267static void smc_nl_prep_smcd_dev(struct smcd_dev_list *dev_list,
268 struct sk_buff *skb,
269 struct netlink_callback *cb)
270{
271 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
272 int snum = cb_ctx->pos[0];
273 struct smcd_dev *smcd;
274 int num = 0;
275
276 mutex_lock(&dev_list->mutex);
277 list_for_each_entry(smcd, &dev_list->list, list) {
278 if (num < snum)
279 goto next;
280 if (smc_nl_handle_smcd_dev(smcd, skb, cb))
281 goto errout;
282next:
283 num++;
284 }
285errout:
286 mutex_unlock(&dev_list->mutex);
287 cb_ctx->pos[0] = num;
288}
289
290int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
291{
292 smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb);
293 return skb->len;
294}
295
296struct smc_ism_event_work {
297 struct work_struct work;
298 struct smcd_dev *smcd;
299 struct smcd_event event;
300};
301
302#define ISM_EVENT_REQUEST 0x0001
303#define ISM_EVENT_RESPONSE 0x0002
304#define ISM_EVENT_REQUEST_IR 0x00000001
305#define ISM_EVENT_CODE_SHUTDOWN 0x80
306#define ISM_EVENT_CODE_TESTLINK 0x83
307
308union smcd_sw_event_info {
309 u64 info;
310 struct {
311 u8 uid[SMC_LGR_ID_SIZE];
312 unsigned short vlan_id;
313 u16 code;
314 };
315};
316
317static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
318{
319 union smcd_sw_event_info ev_info;
320
321 ev_info.info = wrk->event.info;
322 switch (wrk->event.code) {
323 case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */
324 smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id);
325 break;
326 case ISM_EVENT_CODE_TESTLINK: /* Activity timer */
327 if (ev_info.code == ISM_EVENT_REQUEST) {
328 ev_info.code = ISM_EVENT_RESPONSE;
329 wrk->smcd->ops->signal_event(wrk->smcd,
330 wrk->event.tok,
331 ISM_EVENT_REQUEST_IR,
332 ISM_EVENT_CODE_TESTLINK,
333 ev_info.info);
334 }
335 break;
336 }
337}
338
339int smc_ism_signal_shutdown(struct smc_link_group *lgr)
340{
341 int rc;
342 union smcd_sw_event_info ev_info;
343
344 if (lgr->peer_shutdown)
345 return 0;
346
347 memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
348 ev_info.vlan_id = lgr->vlan_id;
349 ev_info.code = ISM_EVENT_REQUEST;
350 rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid,
351 ISM_EVENT_REQUEST_IR,
352 ISM_EVENT_CODE_SHUTDOWN,
353 ev_info.info);
354 return rc;
355}
356
357/* worker for SMC-D events */
358static void smc_ism_event_work(struct work_struct *work)
359{
360 struct smc_ism_event_work *wrk =
361 container_of(work, struct smc_ism_event_work, work);
362
363 switch (wrk->event.type) {
364 case ISM_EVENT_GID: /* GID event, token is peer GID */
365 smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK);
366 break;
367 case ISM_EVENT_DMB:
368 break;
369 case ISM_EVENT_SWR: /* Software defined event */
370 smcd_handle_sw_event(wrk);
371 break;
372 }
373 kfree(wrk);
374}
375
376static void smcd_release(struct device *dev)
377{
378 struct smcd_dev *smcd = container_of(dev, struct smcd_dev, dev);
379
380 kfree(smcd->conn);
381 kfree(smcd);
382}
383
384struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
385 const struct smcd_ops *ops, int max_dmbs)
386{
387 struct smcd_dev *smcd;
388
389 smcd = kzalloc(sizeof(*smcd), GFP_KERNEL);
390 if (!smcd)
391 return NULL;
392 smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *),
393 GFP_KERNEL);
394 if (!smcd->conn) {
395 kfree(smcd);
396 return NULL;
397 }
398
399 smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
400 WQ_MEM_RECLAIM, name);
401 if (!smcd->event_wq) {
402 kfree(smcd->conn);
403 kfree(smcd);
404 return NULL;
405 }
406
407 smcd->dev.parent = parent;
408 smcd->dev.release = smcd_release;
409 device_initialize(&smcd->dev);
410 dev_set_name(&smcd->dev, name);
411 smcd->ops = ops;
412 if (smc_pnetid_by_dev_port(parent, 0, smcd->pnetid))
413 smc_pnetid_by_table_smcd(smcd);
414
415 spin_lock_init(&smcd->lock);
416 spin_lock_init(&smcd->lgr_lock);
417 INIT_LIST_HEAD(&smcd->vlan);
418 INIT_LIST_HEAD(&smcd->lgr_list);
419 init_waitqueue_head(&smcd->lgrs_deleted);
420 return smcd;
421}
422EXPORT_SYMBOL_GPL(smcd_alloc_dev);
423
424int smcd_register_dev(struct smcd_dev *smcd)
425{
426 int rc;
427
428 mutex_lock(&smcd_dev_list.mutex);
429 if (list_empty(&smcd_dev_list.list)) {
430 u8 *system_eid = NULL;
431
432 system_eid = smcd->ops->get_system_eid();
433 if (system_eid[24] != '0' || system_eid[28] != '0') {
434 smc_ism_v2_capable = true;
435 memcpy(smc_ism_v2_system_eid, system_eid,
436 SMC_MAX_EID_LEN);
437 }
438 }
439 /* sort list: devices without pnetid before devices with pnetid */
440 if (smcd->pnetid[0])
441 list_add_tail(&smcd->list, &smcd_dev_list.list);
442 else
443 list_add(&smcd->list, &smcd_dev_list.list);
444 mutex_unlock(&smcd_dev_list.mutex);
445
446 pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",
447 dev_name(&smcd->dev), smcd->pnetid,
448 smcd->pnetid_by_user ? " (user defined)" : "");
449
450 rc = device_add(&smcd->dev);
451 if (rc) {
452 mutex_lock(&smcd_dev_list.mutex);
453 list_del(&smcd->list);
454 mutex_unlock(&smcd_dev_list.mutex);
455 }
456
457 return rc;
458}
459EXPORT_SYMBOL_GPL(smcd_register_dev);
460
461void smcd_unregister_dev(struct smcd_dev *smcd)
462{
463 pr_warn_ratelimited("smc: removing smcd device %s\n",
464 dev_name(&smcd->dev));
465 mutex_lock(&smcd_dev_list.mutex);
466 list_del_init(&smcd->list);
467 mutex_unlock(&smcd_dev_list.mutex);
468 smcd->going_away = 1;
469 smc_smcd_terminate_all(smcd);
470 destroy_workqueue(smcd->event_wq);
471
472 device_del(&smcd->dev);
473}
474EXPORT_SYMBOL_GPL(smcd_unregister_dev);
475
476void smcd_free_dev(struct smcd_dev *smcd)
477{
478 put_device(&smcd->dev);
479}
480EXPORT_SYMBOL_GPL(smcd_free_dev);
481
482/* SMCD Device event handler. Called from ISM device interrupt handler.
483 * Parameters are smcd device pointer,
484 * - event->type (0 --> DMB, 1 --> GID),
485 * - event->code (event code),
486 * - event->tok (either DMB token when event type 0, or GID when event type 1)
487 * - event->time (time of day)
488 * - event->info (debug info).
489 *
490 * Context:
491 * - Function called in IRQ context from ISM device driver event handler.
492 */
493void smcd_handle_event(struct smcd_dev *smcd, struct smcd_event *event)
494{
495 struct smc_ism_event_work *wrk;
496
497 if (smcd->going_away)
498 return;
499 /* copy event to event work queue, and let it be handled there */
500 wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
501 if (!wrk)
502 return;
503 INIT_WORK(&wrk->work, smc_ism_event_work);
504 wrk->smcd = smcd;
505 wrk->event = *event;
506 queue_work(smcd->event_wq, &wrk->work);
507}
508EXPORT_SYMBOL_GPL(smcd_handle_event);
509
510/* SMCD Device interrupt handler. Called from ISM device interrupt handler.
511 * Parameters are smcd device pointer, DMB number, and the DMBE bitmask.
512 * Find the connection and schedule the tasklet for this connection.
513 *
514 * Context:
515 * - Function called in IRQ context from ISM device driver IRQ handler.
516 */
517void smcd_handle_irq(struct smcd_dev *smcd, unsigned int dmbno, u16 dmbemask)
518{
519 struct smc_connection *conn = NULL;
520 unsigned long flags;
521
522 spin_lock_irqsave(&smcd->lock, flags);
523 conn = smcd->conn[dmbno];
524 if (conn && !conn->killed)
525 tasklet_schedule(&conn->rx_tsklet);
526 spin_unlock_irqrestore(&smcd->lock, flags);
527}
528EXPORT_SYMBOL_GPL(smcd_handle_irq);
529
530void __init smc_ism_init(void)
531{
532 smc_ism_v2_capable = false;
533 memset(smc_ism_v2_system_eid, 0, SMC_MAX_EID_LEN);
534}