summaryrefslogtreecommitdiff
path: root/net/smc/smc_ism.c
blob: ac88de2a06a0170a9b0875825179eb398777b9c6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
// SPDX-License-Identifier: GPL-2.0
/* Shared Memory Communications Direct over ISM devices (SMC-D)
 *
 * Functions for ISM device.
 *
 * Copyright IBM Corp. 2018
 */

#include <linux/if_vlan.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <asm/page.h>

#include "smc.h"
#include "smc_core.h"
#include "smc_ism.h"
#include "smc_pnet.h"
#include "smc_netlink.h"
#include "linux/ism.h"

struct smcd_dev_list smcd_dev_list = {
	.list = LIST_HEAD_INIT(smcd_dev_list.list),
	.mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex)
};

static bool smc_ism_v2_capable;
static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN];

#if IS_ENABLED(CONFIG_ISM)
static void smcd_register_dev(struct ism_dev *ism);
static void smcd_unregister_dev(struct ism_dev *ism);
static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event);
static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno,
			    u16 dmbemask);

static struct ism_client smc_ism_client = {
	.name = "SMC-D",
	.add = smcd_register_dev,
	.remove = smcd_unregister_dev,
	.handle_event = smcd_handle_event,
	.handle_irq = smcd_handle_irq,
};
#endif

static void smc_ism_create_system_eid(void)
{
	struct smc_ism_seid *seid =
		(struct smc_ism_seid *)smc_ism_v2_system_eid;
#if IS_ENABLED(CONFIG_S390)
	struct cpuid id;
	u16 ident_tail;
	char tmp[5];

	memcpy(seid->seid_string, "IBM-SYSZ-ISMSEID00000000", 24);
	get_cpu_id(&id);
	ident_tail = (u16)(id.ident & SMC_ISM_IDENT_MASK);
	snprintf(tmp, 5, "%04X", ident_tail);
	memcpy(seid->serial_number, tmp, 4);
	snprintf(tmp, 5, "%04X", id.machine);
	memcpy(seid->type, tmp, 4);
#else
	memset(seid, 0, SMC_MAX_EID_LEN);
#endif
}

/* Test if an ISM communication is possible - same CPC */
int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
		    struct smcd_dev *smcd)
{
	return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0,
					   vlan_id);
}

void smc_ism_get_system_eid(u8 **eid)
{
	if (!smc_ism_v2_capable)
		*eid = NULL;
	else
		*eid = smc_ism_v2_system_eid;
}

u16 smc_ism_get_chid(struct smcd_dev *smcd)
{
	return smcd->ops->get_chid(smcd);
}

/* HW supports ISM V2 and thus System EID is defined */
bool smc_ism_is_v2_capable(void)
{
	return smc_ism_v2_capable;
}

/* Set a connection using this DMBE. */
void smc_ism_set_conn(struct smc_connection *conn)
{
	unsigned long flags;

	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn;
	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
}

/* Unset a connection using this DMBE. */
void smc_ism_unset_conn(struct smc_connection *conn)
{
	unsigned long flags;

	if (!conn->rmb_desc)
		return;

	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL;
	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
}

/* Register a VLAN identifier with the ISM device. Use a reference count
 * and add a VLAN identifier only when the first DMB using this VLAN is
 * registered.
 */
int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
{
	struct smc_ism_vlanid *new_vlan, *vlan;
	unsigned long flags;
	int rc = 0;

	if (!vlanid)			/* No valid vlan id */
		return -EINVAL;

	/* create new vlan entry, in case we need it */
	new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL);
	if (!new_vlan)
		return -ENOMEM;
	new_vlan->vlanid = vlanid;
	refcount_set(&new_vlan->refcnt, 1);

	/* if there is an existing entry, increase count and return */
	spin_lock_irqsave(&smcd->lock, flags);
	list_for_each_entry(vlan, &smcd->vlan, list) {
		if (vlan->vlanid == vlanid) {
			refcount_inc(&vlan->refcnt);
			kfree(new_vlan);
			goto out;
		}
	}

	/* no existing entry found.
	 * add new entry to device; might fail, e.g., if HW limit reached
	 */
	if (smcd->ops->add_vlan_id(smcd, vlanid)) {
		kfree(new_vlan);
		rc = -EIO;
		goto out;
	}
	list_add_tail(&new_vlan->list, &smcd->vlan);
out:
	spin_unlock_irqrestore(&smcd->lock, flags);
	return rc;
}

/* Unregister a VLAN identifier with the ISM device. Use a reference count
 * and remove a VLAN identifier only when the last DMB using this VLAN is
 * unregistered.
 */
int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
{
	struct smc_ism_vlanid *vlan;
	unsigned long flags;
	bool found = false;
	int rc = 0;

	if (!vlanid)			/* No valid vlan id */
		return -EINVAL;

	spin_lock_irqsave(&smcd->lock, flags);
	list_for_each_entry(vlan, &smcd->vlan, list) {
		if (vlan->vlanid == vlanid) {
			if (!refcount_dec_and_test(&vlan->refcnt))
				goto out;
			found = true;
			break;
		}
	}
	if (!found) {
		rc = -ENOENT;
		goto out;		/* VLAN id not in table */
	}

	/* Found and the last reference just gone */
	if (smcd->ops->del_vlan_id(smcd, vlanid))
		rc = -EIO;
	list_del(&vlan->list);
	kfree(vlan);
out:
	spin_unlock_irqrestore(&smcd->lock, flags);
	return rc;
}

int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc)
{
	struct smcd_dmb dmb;
	int rc = 0;

	if (!dmb_desc->dma_addr)
		return rc;

	memset(&dmb, 0, sizeof(dmb));
	dmb.dmb_tok = dmb_desc->token;
	dmb.sba_idx = dmb_desc->sba_idx;
	dmb.cpu_addr = dmb_desc->cpu_addr;
	dmb.dma_addr = dmb_desc->dma_addr;
	dmb.dmb_len = dmb_desc->len;
	rc = smcd->ops->unregister_dmb(smcd, &dmb);
	if (!rc || rc == ISM_ERROR) {
		dmb_desc->cpu_addr = NULL;
		dmb_desc->dma_addr = 0;
	}

	return rc;
}

int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
			 struct smc_buf_desc *dmb_desc)
{
#if IS_ENABLED(CONFIG_ISM)
	struct smcd_dmb dmb;
	int rc;

	memset(&dmb, 0, sizeof(dmb));
	dmb.dmb_len = dmb_len;
	dmb.sba_idx = dmb_desc->sba_idx;
	dmb.vlan_id = lgr->vlan_id;
	dmb.rgid = lgr->peer_gid.gid;
	rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb, &smc_ism_client);
	if (!rc) {
		dmb_desc->sba_idx = dmb.sba_idx;
		dmb_desc->token = dmb.dmb_tok;
		dmb_desc->cpu_addr = dmb.cpu_addr;
		dmb_desc->dma_addr = dmb.dma_addr;
		dmb_desc->len = dmb.dmb_len;
	}
	return rc;
#else
	return 0;
#endif
}

static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd,
				  struct sk_buff *skb,
				  struct netlink_callback *cb)
{
	char smc_pnet[SMC_MAX_PNETID_LEN + 1];
	struct smc_pci_dev smc_pci_dev;
	struct nlattr *port_attrs;
	struct nlattr *attrs;
	struct ism_dev *ism;
	int use_cnt = 0;
	void *nlh;

	ism = smcd->priv;
	nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
			  &smc_gen_nl_family, NLM_F_MULTI,
			  SMC_NETLINK_GET_DEV_SMCD);
	if (!nlh)
		goto errmsg;
	attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD);
	if (!attrs)
		goto errout;
	use_cnt = atomic_read(&smcd->lgr_cnt);
	if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt))
		goto errattr;
	if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0))
		goto errattr;
	memset(&smc_pci_dev, 0, sizeof(smc_pci_dev));
	smc_set_pci_values(to_pci_dev(ism->dev.parent), &smc_pci_dev);
	if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid))
		goto errattr;
	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid))
		goto errattr;
	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor))
		goto errattr;
	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device))
		goto errattr;
	if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id))
		goto errattr;

	port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT);
	if (!port_attrs)
		goto errattr;
	if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user))
		goto errportattr;
	memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN);
	smc_pnet[SMC_MAX_PNETID_LEN] = 0;
	if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet))
		goto errportattr;

	nla_nest_end(skb, port_attrs);
	nla_nest_end(skb, attrs);
	genlmsg_end(skb, nlh);
	return 0;

errportattr:
	nla_nest_cancel(skb, port_attrs);
errattr:
	nla_nest_cancel(skb, attrs);
errout:
	nlmsg_cancel(skb, nlh);
errmsg:
	return -EMSGSIZE;
}

static void smc_nl_prep_smcd_dev(struct smcd_dev_list *dev_list,
				 struct sk_buff *skb,
				 struct netlink_callback *cb)
{
	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
	int snum = cb_ctx->pos[0];
	struct smcd_dev *smcd;
	int num = 0;

	mutex_lock(&dev_list->mutex);
	list_for_each_entry(smcd, &dev_list->list, list) {
		if (num < snum)
			goto next;
		if (smc_nl_handle_smcd_dev(smcd, skb, cb))
			goto errout;
next:
		num++;
	}
errout:
	mutex_unlock(&dev_list->mutex);
	cb_ctx->pos[0] = num;
}

int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
{
	smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb);
	return skb->len;
}

#if IS_ENABLED(CONFIG_ISM)
struct smc_ism_event_work {
	struct work_struct work;
	struct smcd_dev *smcd;
	struct ism_event event;
};

#define ISM_EVENT_REQUEST		0x0001
#define ISM_EVENT_RESPONSE		0x0002
#define ISM_EVENT_REQUEST_IR		0x00000001
#define ISM_EVENT_CODE_SHUTDOWN		0x80
#define ISM_EVENT_CODE_TESTLINK		0x83

union smcd_sw_event_info {
	u64	info;
	struct {
		u8		uid[SMC_LGR_ID_SIZE];
		unsigned short	vlan_id;
		u16		code;
	};
};

static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
{
	struct smcd_gid peer_gid = { .gid = wrk->event.tok,
				     .gid_ext = 0 };
	union smcd_sw_event_info ev_info;

	ev_info.info = wrk->event.info;
	switch (wrk->event.code) {
	case ISM_EVENT_CODE_SHUTDOWN:	/* Peer shut down DMBs */
		smc_smcd_terminate(wrk->smcd, &peer_gid, ev_info.vlan_id);
		break;
	case ISM_EVENT_CODE_TESTLINK:	/* Activity timer */
		if (ev_info.code == ISM_EVENT_REQUEST) {
			ev_info.code = ISM_EVENT_RESPONSE;
			wrk->smcd->ops->signal_event(wrk->smcd,
						     &peer_gid,
						     ISM_EVENT_REQUEST_IR,
						     ISM_EVENT_CODE_TESTLINK,
						     ev_info.info);
			}
		break;
	}
}

/* worker for SMC-D events */
static void smc_ism_event_work(struct work_struct *work)
{
	struct smc_ism_event_work *wrk =
		container_of(work, struct smc_ism_event_work, work);
	struct smcd_gid smcd_gid = { .gid = wrk->event.tok,
				     .gid_ext = 0 };

	switch (wrk->event.type) {
	case ISM_EVENT_GID:	/* GID event, token is peer GID */
		smc_smcd_terminate(wrk->smcd, &smcd_gid, VLAN_VID_MASK);
		break;
	case ISM_EVENT_DMB:
		break;
	case ISM_EVENT_SWR:	/* Software defined event */
		smcd_handle_sw_event(wrk);
		break;
	}
	kfree(wrk);
}

static struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
				       const struct smcd_ops *ops, int max_dmbs)
{
	struct smcd_dev *smcd;

	smcd = devm_kzalloc(parent, sizeof(*smcd), GFP_KERNEL);
	if (!smcd)
		return NULL;
	smcd->conn = devm_kcalloc(parent, max_dmbs,
				  sizeof(struct smc_connection *), GFP_KERNEL);
	if (!smcd->conn)
		return NULL;

	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
						 WQ_MEM_RECLAIM, name);
	if (!smcd->event_wq)
		return NULL;

	smcd->ops = ops;

	spin_lock_init(&smcd->lock);
	spin_lock_init(&smcd->lgr_lock);
	INIT_LIST_HEAD(&smcd->vlan);
	INIT_LIST_HEAD(&smcd->lgr_list);
	init_waitqueue_head(&smcd->lgrs_deleted);
	return smcd;
}

static void smcd_register_dev(struct ism_dev *ism)
{
	const struct smcd_ops *ops = ism_get_smcd_ops();
	struct smcd_dev *smcd;

	if (!ops)
		return;

	smcd = smcd_alloc_dev(&ism->pdev->dev, dev_name(&ism->pdev->dev), ops,
			      ISM_NR_DMBS);
	if (!smcd)
		return;
	smcd->priv = ism;
	ism_set_priv(ism, &smc_ism_client, smcd);
	if (smc_pnetid_by_dev_port(&ism->pdev->dev, 0, smcd->pnetid))
		smc_pnetid_by_table_smcd(smcd);

	mutex_lock(&smcd_dev_list.mutex);
	if (list_empty(&smcd_dev_list.list)) {
		if (smcd->ops->supports_v2())
			smc_ism_v2_capable = true;
	}
	/* sort list: devices without pnetid before devices with pnetid */
	if (smcd->pnetid[0])
		list_add_tail(&smcd->list, &smcd_dev_list.list);
	else
		list_add(&smcd->list, &smcd_dev_list.list);
	mutex_unlock(&smcd_dev_list.mutex);

	pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",
			    dev_name(&ism->dev), smcd->pnetid,
			    smcd->pnetid_by_user ? " (user defined)" : "");

	return;
}

static void smcd_unregister_dev(struct ism_dev *ism)
{
	struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client);

	pr_warn_ratelimited("smc: removing smcd device %s\n",
			    dev_name(&ism->dev));
	smcd->going_away = 1;
	smc_smcd_terminate_all(smcd);
	mutex_lock(&smcd_dev_list.mutex);
	list_del_init(&smcd->list);
	mutex_unlock(&smcd_dev_list.mutex);
	destroy_workqueue(smcd->event_wq);
}

/* SMCD Device event handler. Called from ISM device interrupt handler.
 * Parameters are ism device pointer,
 * - event->type (0 --> DMB, 1 --> GID),
 * - event->code (event code),
 * - event->tok (either DMB token when event type 0, or GID when event type 1)
 * - event->time (time of day)
 * - event->info (debug info).
 *
 * Context:
 * - Function called in IRQ context from ISM device driver event handler.
 */
static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event)
{
	struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client);
	struct smc_ism_event_work *wrk;

	if (smcd->going_away)
		return;
	/* copy event to event work queue, and let it be handled there */
	wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
	if (!wrk)
		return;
	INIT_WORK(&wrk->work, smc_ism_event_work);
	wrk->smcd = smcd;
	wrk->event = *event;
	queue_work(smcd->event_wq, &wrk->work);
}

/* SMCD Device interrupt handler. Called from ISM device interrupt handler.
 * Parameters are the ism device pointer, DMB number, and the DMBE bitmask.
 * Find the connection and schedule the tasklet for this connection.
 *
 * Context:
 * - Function called in IRQ context from ISM device driver IRQ handler.
 */
static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno,
			    u16 dmbemask)
{
	struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client);
	struct smc_connection *conn = NULL;
	unsigned long flags;

	spin_lock_irqsave(&smcd->lock, flags);
	conn = smcd->conn[dmbno];
	if (conn && !conn->killed)
		tasklet_schedule(&conn->rx_tsklet);
	spin_unlock_irqrestore(&smcd->lock, flags);
}
#endif

int smc_ism_signal_shutdown(struct smc_link_group *lgr)
{
	int rc = 0;
#if IS_ENABLED(CONFIG_ISM)
	union smcd_sw_event_info ev_info;

	if (lgr->peer_shutdown)
		return 0;

	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
	ev_info.vlan_id = lgr->vlan_id;
	ev_info.code = ISM_EVENT_REQUEST;
	rc = lgr->smcd->ops->signal_event(lgr->smcd, &lgr->peer_gid,
					  ISM_EVENT_REQUEST_IR,
					  ISM_EVENT_CODE_SHUTDOWN,
					  ev_info.info);
#endif
	return rc;
}

int smc_ism_init(void)
{
	int rc = 0;

	smc_ism_v2_capable = false;
	smc_ism_create_system_eid();

#if IS_ENABLED(CONFIG_ISM)
	rc = ism_register_client(&smc_ism_client);
#endif
	return rc;
}

void smc_ism_exit(void)
{
#if IS_ENABLED(CONFIG_ISM)
	ism_unregister_client(&smc_ism_client);
#endif
}