summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/snic/snic_disc.c
blob: 6c529b37f3b46f770e4cb4a543c250c10685c97f (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
// SPDX-License-Identifier: GPL-2.0-only
// Copyright 2014 Cisco Systems, Inc.  All rights reserved.

#include <linux/errno.h>
#include <linux/mempool.h>

#include <scsi/scsi_tcq.h>

#include "snic_disc.h"
#include "snic.h"
#include "snic_io.h"


/* snic target types */
static const char * const snic_tgt_type_str[] = {
	[SNIC_TGT_DAS] = "DAS",
	[SNIC_TGT_SAN] = "SAN",
};

static inline const char *
snic_tgt_type_to_str(int typ)
{
	return ((typ > SNIC_TGT_NONE && typ <= SNIC_TGT_SAN) ?
		 snic_tgt_type_str[typ] : "Unknown");
}

static const char * const snic_tgt_state_str[] = {
	[SNIC_TGT_STAT_INIT]	= "INIT",
	[SNIC_TGT_STAT_ONLINE]	= "ONLINE",
	[SNIC_TGT_STAT_OFFLINE]	= "OFFLINE",
	[SNIC_TGT_STAT_DEL]	= "DELETION IN PROGRESS",
};

const char *
snic_tgt_state_to_str(int state)
{
	return ((state >= SNIC_TGT_STAT_INIT && state <= SNIC_TGT_STAT_DEL) ?
		snic_tgt_state_str[state] : "UNKNOWN");
}

/*
 * Initiate report_tgt req desc
 */
static void
snic_report_tgt_init(struct snic_host_req *req, u32 hid, u8 *buf, u32 len,
		     dma_addr_t rsp_buf_pa, ulong ctx)
{
	struct snic_sg_desc *sgd = NULL;


	snic_io_hdr_enc(&req->hdr, SNIC_REQ_REPORT_TGTS, 0, SCSI_NO_TAG, hid,
			1, ctx);

	req->u.rpt_tgts.sg_cnt = cpu_to_le16(1);
	sgd = req_to_sgl(req);
	sgd[0].addr = cpu_to_le64(rsp_buf_pa);
	sgd[0].len = cpu_to_le32(len);
	sgd[0]._resvd = 0;
	req->u.rpt_tgts.sg_addr = cpu_to_le64((ulong)sgd);
}

/*
 * snic_queue_report_tgt_req: Queues report target request.
 */
static int
snic_queue_report_tgt_req(struct snic *snic)
{
	struct snic_req_info *rqi = NULL;
	u32 ntgts, buf_len = 0;
	u8 *buf = NULL;
	dma_addr_t pa = 0;
	int ret = 0;

	rqi = snic_req_init(snic, 1);
	if (!rqi) {
		ret = -ENOMEM;
		goto error;
	}

	if (snic->fwinfo.max_tgts)
		ntgts = min_t(u32, snic->fwinfo.max_tgts, snic->shost->max_id);
	else
		ntgts = snic->shost->max_id;

	/* Allocate Response Buffer */
	SNIC_BUG_ON(ntgts == 0);
	buf_len = ntgts * sizeof(struct snic_tgt_id) + SNIC_SG_DESC_ALIGN;

	buf = kzalloc(buf_len, GFP_KERNEL);
	if (!buf) {
		snic_req_free(snic, rqi);
		SNIC_HOST_ERR(snic->shost, "Resp Buf Alloc Failed.\n");

		ret = -ENOMEM;
		goto error;
	}

	SNIC_BUG_ON((((unsigned long)buf) % SNIC_SG_DESC_ALIGN) != 0);

	pa = dma_map_single(&snic->pdev->dev, buf, buf_len, DMA_FROM_DEVICE);
	if (dma_mapping_error(&snic->pdev->dev, pa)) {
		SNIC_HOST_ERR(snic->shost,
			      "Rpt-tgt rspbuf %p: PCI DMA Mapping Failed\n",
			      buf);
		kfree(buf);
		snic_req_free(snic, rqi);
		ret = -EINVAL;

		goto error;
	}


	SNIC_BUG_ON(pa == 0);
	rqi->sge_va = (ulong) buf;

	snic_report_tgt_init(rqi->req,
			     snic->config.hid,
			     buf,
			     buf_len,
			     pa,
			     (ulong)rqi);

	snic_handle_untagged_req(snic, rqi);

	ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
	if (ret) {
		dma_unmap_single(&snic->pdev->dev, pa, buf_len,
				 DMA_FROM_DEVICE);
		kfree(buf);
		rqi->sge_va = 0;
		snic_release_untagged_req(snic, rqi);
		SNIC_HOST_ERR(snic->shost, "Queuing Report Tgts Failed.\n");

		goto error;
	}

	SNIC_DISC_DBG(snic->shost, "Report Targets Issued.\n");

	return ret;

error:
	SNIC_HOST_ERR(snic->shost,
		      "Queuing Report Targets Failed, err = %d\n",
		      ret);
	return ret;
} /* end of snic_queue_report_tgt_req */

/* call into SML */
static void
snic_scsi_scan_tgt(struct work_struct *work)
{
	struct snic_tgt *tgt = container_of(work, struct snic_tgt, scan_work);
	struct Scsi_Host *shost = dev_to_shost(&tgt->dev);
	unsigned long flags;

	SNIC_HOST_INFO(shost, "Scanning Target id 0x%x\n", tgt->id);
	scsi_scan_target(&tgt->dev,
			 tgt->channel,
			 tgt->scsi_tgt_id,
			 SCAN_WILD_CARD,
			 SCSI_SCAN_RESCAN);

	spin_lock_irqsave(shost->host_lock, flags);
	tgt->flags &= ~SNIC_TGT_SCAN_PENDING;
	spin_unlock_irqrestore(shost->host_lock, flags);
} /* end of snic_scsi_scan_tgt */

/*
 * snic_tgt_lookup :
 */
static struct snic_tgt *
snic_tgt_lookup(struct snic *snic, struct snic_tgt_id *tgtid)
{
	struct list_head *cur, *nxt;
	struct snic_tgt *tgt = NULL;

	list_for_each_safe(cur, nxt, &snic->disc.tgt_list) {
		tgt = list_entry(cur, struct snic_tgt, list);
		if (tgt->id == le32_to_cpu(tgtid->tgt_id))
			return tgt;
		tgt = NULL;
	}

	return tgt;
} /* end of snic_tgt_lookup */

/*
 * snic_tgt_dev_release : Called on dropping last ref for snic_tgt object
 */
void
snic_tgt_dev_release(struct device *dev)
{
	struct snic_tgt *tgt = dev_to_tgt(dev);

	SNIC_HOST_INFO(snic_tgt_to_shost(tgt),
		       "Target Device ID %d (%s) Permanently Deleted.\n",
		       tgt->id,
		       dev_name(dev));

	SNIC_BUG_ON(!list_empty(&tgt->list));
	kfree(tgt);
}

/*
 * snic_tgt_del : work function to delete snic_tgt
 */
static void
snic_tgt_del(struct work_struct *work)
{
	struct snic_tgt *tgt = container_of(work, struct snic_tgt, del_work);
	struct Scsi_Host *shost = snic_tgt_to_shost(tgt);

	if (tgt->flags & SNIC_TGT_SCAN_PENDING)
		scsi_flush_work(shost);

	/* Block IOs on child devices, stops new IOs */
	scsi_target_block(&tgt->dev);

	/* Cleanup IOs */
	snic_tgt_scsi_abort_io(tgt);

	/* Unblock IOs now, to flush if there are any. */
	scsi_target_unblock(&tgt->dev, SDEV_TRANSPORT_OFFLINE);

	/* Delete SCSI Target and sdevs */
	scsi_remove_target(&tgt->dev);  /* ?? */
	device_del(&tgt->dev);
	put_device(&tgt->dev);
} /* end of snic_tgt_del */

/* snic_tgt_create: checks for existence of snic_tgt, if it doesn't
 * it creates one.
 */
static struct snic_tgt *
snic_tgt_create(struct snic *snic, struct snic_tgt_id *tgtid)
{
	struct snic_tgt *tgt = NULL;
	unsigned long flags;
	int ret;

	tgt = snic_tgt_lookup(snic, tgtid);
	if (tgt) {
		/* update the information if required */
		return tgt;
	}

	tgt = kzalloc(sizeof(*tgt), GFP_KERNEL);
	if (!tgt) {
		SNIC_HOST_ERR(snic->shost, "Failure to allocate snic_tgt.\n");
		ret = -ENOMEM;

		return tgt;
	}

	INIT_LIST_HEAD(&tgt->list);
	tgt->id = le32_to_cpu(tgtid->tgt_id);
	tgt->channel = 0;

	SNIC_BUG_ON(le16_to_cpu(tgtid->tgt_type) > SNIC_TGT_SAN);
	tgt->tdata.typ = le16_to_cpu(tgtid->tgt_type);

	/*
	 * Plugging into SML Device Tree
	 */
	tgt->tdata.disc_id = 0;
	tgt->state = SNIC_TGT_STAT_INIT;
	device_initialize(&tgt->dev);
	tgt->dev.parent = get_device(&snic->shost->shost_gendev);
	tgt->dev.release = snic_tgt_dev_release;
	INIT_WORK(&tgt->scan_work, snic_scsi_scan_tgt);
	INIT_WORK(&tgt->del_work, snic_tgt_del);
	switch (tgt->tdata.typ) {
	case SNIC_TGT_DAS:
		dev_set_name(&tgt->dev, "snic_das_tgt:%d:%d-%d",
			     snic->shost->host_no, tgt->channel, tgt->id);
		break;

	case SNIC_TGT_SAN:
		dev_set_name(&tgt->dev, "snic_san_tgt:%d:%d-%d",
			     snic->shost->host_no, tgt->channel, tgt->id);
		break;

	default:
		SNIC_HOST_INFO(snic->shost, "Target type Unknown Detected.\n");
		dev_set_name(&tgt->dev, "snic_das_tgt:%d:%d-%d",
			     snic->shost->host_no, tgt->channel, tgt->id);
		break;
	}

	spin_lock_irqsave(snic->shost->host_lock, flags);
	list_add_tail(&tgt->list, &snic->disc.tgt_list);
	tgt->scsi_tgt_id = snic->disc.nxt_tgt_id++;
	tgt->state = SNIC_TGT_STAT_ONLINE;
	spin_unlock_irqrestore(snic->shost->host_lock, flags);

	SNIC_HOST_INFO(snic->shost,
		       "Tgt %d, type = %s detected. Adding..\n",
		       tgt->id, snic_tgt_type_to_str(tgt->tdata.typ));

	ret = device_add(&tgt->dev);
	if (ret) {
		SNIC_HOST_ERR(snic->shost,
			      "Snic Tgt: device_add, with err = %d\n",
			      ret);

		put_device(&snic->shost->shost_gendev);
		spin_lock_irqsave(snic->shost->host_lock, flags);
		list_del(&tgt->list);
		spin_unlock_irqrestore(snic->shost->host_lock, flags);
		put_device(&tgt->dev);
		tgt = NULL;

		return tgt;
	}

	SNIC_HOST_INFO(snic->shost, "Scanning %s.\n", dev_name(&tgt->dev));

	scsi_queue_work(snic->shost, &tgt->scan_work);

	return tgt;
} /* end of snic_tgt_create */

/* Handler for discovery */
void
snic_handle_tgt_disc(struct work_struct *work)
{
	struct snic *snic = container_of(work, struct snic, tgt_work);
	struct snic_tgt_id *tgtid = NULL;
	struct snic_tgt *tgt = NULL;
	unsigned long flags;
	int i;

	spin_lock_irqsave(&snic->snic_lock, flags);
	if (snic->in_remove) {
		spin_unlock_irqrestore(&snic->snic_lock, flags);
		kfree(snic->disc.rtgt_info);

		return;
	}
	spin_unlock_irqrestore(&snic->snic_lock, flags);

	mutex_lock(&snic->disc.mutex);
	/* Discover triggered during disc in progress */
	if (snic->disc.req_cnt) {
		snic->disc.state = SNIC_DISC_DONE;
		snic->disc.req_cnt = 0;
		mutex_unlock(&snic->disc.mutex);
		kfree(snic->disc.rtgt_info);
		snic->disc.rtgt_info = NULL;

		SNIC_HOST_INFO(snic->shost, "tgt_disc: Discovery restart.\n");
		/* Start Discovery Again */
		snic_disc_start(snic);

		return;
	}

	tgtid = (struct snic_tgt_id *)snic->disc.rtgt_info;

	SNIC_BUG_ON(snic->disc.rtgt_cnt == 0 || tgtid == NULL);

	for (i = 0; i < snic->disc.rtgt_cnt; i++) {
		tgt = snic_tgt_create(snic, &tgtid[i]);
		if (!tgt) {
			int buf_sz = snic->disc.rtgt_cnt * sizeof(*tgtid);

			SNIC_HOST_ERR(snic->shost, "Failed to create tgt.\n");
			snic_hex_dump("rpt_tgt_rsp", (char *)tgtid, buf_sz);
			break;
		}
	}

	snic->disc.rtgt_info = NULL;
	snic->disc.state = SNIC_DISC_DONE;
	mutex_unlock(&snic->disc.mutex);

	SNIC_HOST_INFO(snic->shost, "Discovery Completed.\n");

	kfree(tgtid);
} /* end of snic_handle_tgt_disc */


int
snic_report_tgt_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
{

	u8 typ, cmpl_stat;
	u32 cmnd_id, hid, tgt_cnt = 0;
	ulong ctx;
	struct snic_req_info *rqi = NULL;
	struct snic_tgt_id *tgtid;
	int i, ret = 0;

	snic_io_hdr_dec(&fwreq->hdr, &typ, &cmpl_stat, &cmnd_id, &hid, &ctx);
	rqi = (struct snic_req_info *) ctx;
	tgtid = (struct snic_tgt_id *) rqi->sge_va;

	tgt_cnt = le32_to_cpu(fwreq->u.rpt_tgts_cmpl.tgt_cnt);
	if (tgt_cnt == 0) {
		SNIC_HOST_ERR(snic->shost, "No Targets Found on this host.\n");
		ret = 1;

		goto end;
	}

	/* printing list of targets here */
	SNIC_HOST_INFO(snic->shost, "Target Count = %d\n", tgt_cnt);

	SNIC_BUG_ON(tgt_cnt > snic->fwinfo.max_tgts);

	for (i = 0; i < tgt_cnt; i++)
		SNIC_HOST_INFO(snic->shost,
			       "Tgt id = 0x%x\n",
			       le32_to_cpu(tgtid[i].tgt_id));

	/*
	 * Queue work for further processing,
	 * Response Buffer Memory is freed after creating targets
	 */
	snic->disc.rtgt_cnt = tgt_cnt;
	snic->disc.rtgt_info = (u8 *) tgtid;
	queue_work(snic_glob->event_q, &snic->tgt_work);
	ret = 0;

end:
	/* Unmap Response Buffer */
	snic_pci_unmap_rsp_buf(snic, rqi);
	if (ret)
		kfree(tgtid);

	rqi->sge_va = 0;
	snic_release_untagged_req(snic, rqi);

	return ret;
} /* end of snic_report_tgt_cmpl_handler */

/* Discovery init fn */
void
snic_disc_init(struct snic_disc *disc)
{
	INIT_LIST_HEAD(&disc->tgt_list);
	mutex_init(&disc->mutex);
	disc->disc_id = 0;
	disc->nxt_tgt_id = 0;
	disc->state = SNIC_DISC_INIT;
	disc->req_cnt = 0;
	disc->rtgt_cnt = 0;
	disc->rtgt_info = NULL;
	disc->cb = NULL;
} /* end of snic_disc_init */

/* Discovery, uninit fn */
void
snic_disc_term(struct snic *snic)
{
	struct snic_disc *disc = &snic->disc;

	mutex_lock(&disc->mutex);
	if (disc->req_cnt) {
		disc->req_cnt = 0;
		SNIC_SCSI_DBG(snic->shost, "Terminating Discovery.\n");
	}
	mutex_unlock(&disc->mutex);
}

/*
 * snic_disc_start: Discovery Start ...
 */
int
snic_disc_start(struct snic *snic)
{
	struct snic_disc *disc = &snic->disc;
	unsigned long flags;
	int ret = 0;

	SNIC_SCSI_DBG(snic->shost, "Discovery Start.\n");

	spin_lock_irqsave(&snic->snic_lock, flags);
	if (snic->in_remove) {
		spin_unlock_irqrestore(&snic->snic_lock, flags);
		SNIC_ERR("snic driver removal in progress ...\n");
		ret = 0;

		return ret;
	}
	spin_unlock_irqrestore(&snic->snic_lock, flags);

	mutex_lock(&disc->mutex);
	if (disc->state == SNIC_DISC_PENDING) {
		disc->req_cnt++;
		mutex_unlock(&disc->mutex);

		return ret;
	}
	disc->state = SNIC_DISC_PENDING;
	mutex_unlock(&disc->mutex);

	ret = snic_queue_report_tgt_req(snic);
	if (ret)
		SNIC_HOST_INFO(snic->shost, "Discovery Failed, err=%d.\n", ret);

	return ret;
} /* end of snic_disc_start */

/*
 * snic_disc_work :
 */
void
snic_handle_disc(struct work_struct *work)
{
	struct snic *snic = container_of(work, struct snic, disc_work);
	int ret = 0;

	SNIC_HOST_INFO(snic->shost, "disc_work: Discovery\n");

	ret = snic_disc_start(snic);
	if (ret)
		goto disc_err;

disc_err:
	SNIC_HOST_ERR(snic->shost,
		      "disc_work: Discovery Failed w/ err = %d\n",
		      ret);
} /* end of snic_disc_work */

/*
 * snic_tgt_del_all : cleanup all snic targets
 * Called on unbinding the interface
 */
void
snic_tgt_del_all(struct snic *snic)
{
	struct snic_tgt *tgt = NULL;
	struct list_head *cur, *nxt;
	unsigned long flags;

	scsi_flush_work(snic->shost);

	mutex_lock(&snic->disc.mutex);
	spin_lock_irqsave(snic->shost->host_lock, flags);

	list_for_each_safe(cur, nxt, &snic->disc.tgt_list) {
		tgt = list_entry(cur, struct snic_tgt, list);
		tgt->state = SNIC_TGT_STAT_DEL;
		list_del_init(&tgt->list);
		SNIC_HOST_INFO(snic->shost, "Tgt %d q'ing for del\n", tgt->id);
		queue_work(snic_glob->event_q, &tgt->del_work);
		tgt = NULL;
	}
	spin_unlock_irqrestore(snic->shost->host_lock, flags);
	mutex_unlock(&snic->disc.mutex);

	flush_workqueue(snic_glob->event_q);
} /* end of snic_tgt_del_all */