1/*
2 * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
3 *
4 * This program is free software; you may redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
9 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
10 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
11 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
12 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
13 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
14 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
15 * SOFTWARE.
16 */
17
18#include <linux/errno.h>
19#include <linux/mempool.h>
20
21#include <scsi/scsi_tcq.h>
22
23#include "snic_disc.h"
24#include "snic.h"
25#include "snic_io.h"
26
27
28/* snic target types */
29static const char * const snic_tgt_type_str[] = {
30	[SNIC_TGT_DAS] = "DAS",
31	[SNIC_TGT_SAN] = "SAN",
32};
33
34static inline const char *
35snic_tgt_type_to_str(int typ)
36{
37	return ((typ > SNIC_TGT_NONE && typ <= SNIC_TGT_SAN) ?
38		 snic_tgt_type_str[typ] : "Unknown");
39}
40
41static const char * const snic_tgt_state_str[] = {
42	[SNIC_TGT_STAT_INIT]	= "INIT",
43	[SNIC_TGT_STAT_ONLINE]	= "ONLINE",
44	[SNIC_TGT_STAT_OFFLINE]	= "OFFLINE",
45	[SNIC_TGT_STAT_DEL]	= "DELETION IN PROGRESS",
46};
47
48const char *
49snic_tgt_state_to_str(int state)
50{
51	return ((state >= SNIC_TGT_STAT_INIT && state <= SNIC_TGT_STAT_DEL) ?
52		snic_tgt_state_str[state] : "UNKNOWN");
53}
54
55/*
56 * Initiate report_tgt req desc
57 */
58static void
59snic_report_tgt_init(struct snic_host_req *req, u32 hid, u8 *buf, u32 len,
60		     dma_addr_t rsp_buf_pa, ulong ctx)
61{
62	struct snic_sg_desc *sgd = NULL;
63
64
65	snic_io_hdr_enc(&req->hdr, SNIC_REQ_REPORT_TGTS, 0, SCSI_NO_TAG, hid,
66			1, ctx);
67
68	req->u.rpt_tgts.sg_cnt = cpu_to_le16(1);
69	sgd = req_to_sgl(req);
70	sgd[0].addr = cpu_to_le64(rsp_buf_pa);
71	sgd[0].len = cpu_to_le32(len);
72	sgd[0]._resvd = 0;
73	req->u.rpt_tgts.sg_addr = cpu_to_le64((ulong)sgd);
74}
75
76/*
77 * snic_queue_report_tgt_req: Queues report target request.
78 */
79static int
80snic_queue_report_tgt_req(struct snic *snic)
81{
82	struct snic_req_info *rqi = NULL;
83	u32 ntgts, buf_len = 0;
84	u8 *buf = NULL;
85	dma_addr_t pa = 0;
86	int ret = 0;
87
88	rqi = snic_req_init(snic, 1);
89	if (!rqi) {
90		ret = -ENOMEM;
91		goto error;
92	}
93
94	if (snic->fwinfo.max_tgts)
95		ntgts = min_t(u32, snic->fwinfo.max_tgts, snic->shost->max_id);
96	else
97		ntgts = snic->shost->max_id;
98
99	/* Allocate Response Buffer */
100	SNIC_BUG_ON(ntgts == 0);
101	buf_len = ntgts * sizeof(struct snic_tgt_id) + SNIC_SG_DESC_ALIGN;
102
103	buf = kzalloc(buf_len, GFP_KERNEL|GFP_DMA);
104	if (!buf) {
105		snic_req_free(snic, rqi);
106		SNIC_HOST_ERR(snic->shost, "Resp Buf Alloc Failed.\n");
107
108		ret = -ENOMEM;
109		goto error;
110	}
111
112	SNIC_BUG_ON((((unsigned long)buf) % SNIC_SG_DESC_ALIGN) != 0);
113
114	pa = pci_map_single(snic->pdev, buf, buf_len, PCI_DMA_FROMDEVICE);
115	if (pci_dma_mapping_error(snic->pdev, pa)) {
116		kfree(buf);
117		snic_req_free(snic, rqi);
118		SNIC_HOST_ERR(snic->shost,
119			      "Rpt-tgt rspbuf %p: PCI DMA Mapping Failed\n",
120			      buf);
121		ret = -EINVAL;
122
123		goto error;
124	}
125
126
127	SNIC_BUG_ON(pa == 0);
128	rqi->sge_va = (ulong) buf;
129
130	snic_report_tgt_init(rqi->req,
131			     snic->config.hid,
132			     buf,
133			     buf_len,
134			     pa,
135			     (ulong)rqi);
136
137	snic_handle_untagged_req(snic, rqi);
138
139	ret = snic_queue_wq_desc(snic, rqi->req, rqi->req_len);
140	if (ret) {
141		pci_unmap_single(snic->pdev, pa, buf_len, PCI_DMA_FROMDEVICE);
142		kfree(buf);
143		rqi->sge_va = 0;
144		snic_release_untagged_req(snic, rqi);
145		SNIC_HOST_ERR(snic->shost, "Queuing Report Tgts Failed.\n");
146
147		goto error;
148	}
149
150	SNIC_DISC_DBG(snic->shost, "Report Targets Issued.\n");
151
152	return ret;
153
154error:
155	SNIC_HOST_ERR(snic->shost,
156		      "Queuing Report Targets Failed, err = %d\n",
157		      ret);
158	return ret;
159} /* end of snic_queue_report_tgt_req */
160
161/* call into SML */
162static void
163snic_scsi_scan_tgt(struct work_struct *work)
164{
165	struct snic_tgt *tgt = container_of(work, struct snic_tgt, scan_work);
166	struct Scsi_Host *shost = dev_to_shost(&tgt->dev);
167	unsigned long flags;
168
169	SNIC_HOST_INFO(shost, "Scanning Target id 0x%x\n", tgt->id);
170	scsi_scan_target(&tgt->dev,
171			 tgt->channel,
172			 tgt->scsi_tgt_id,
173			 SCAN_WILD_CARD,
174			 1);
175
176	spin_lock_irqsave(shost->host_lock, flags);
177	tgt->flags &= ~SNIC_TGT_SCAN_PENDING;
178	spin_unlock_irqrestore(shost->host_lock, flags);
179} /* end of snic_scsi_scan_tgt */
180
181/*
182 * snic_tgt_lookup :
183 */
184static struct snic_tgt *
185snic_tgt_lookup(struct snic *snic, struct snic_tgt_id *tgtid)
186{
187	struct list_head *cur, *nxt;
188	struct snic_tgt *tgt = NULL;
189
190	list_for_each_safe(cur, nxt, &snic->disc.tgt_list) {
191		tgt = list_entry(cur, struct snic_tgt, list);
192		if (tgt->id == le32_to_cpu(tgtid->tgt_id))
193			return tgt;
194		tgt = NULL;
195	}
196
197	return tgt;
198} /* end of snic_tgt_lookup */
199
200/*
201 * snic_tgt_dev_release : Called on dropping last ref for snic_tgt object
202 */
203void
204snic_tgt_dev_release(struct device *dev)
205{
206	struct snic_tgt *tgt = dev_to_tgt(dev);
207
208	SNIC_HOST_INFO(snic_tgt_to_shost(tgt),
209		       "Target Device ID %d (%s) Permanently Deleted.\n",
210		       tgt->id,
211		       dev_name(dev));
212
213	SNIC_BUG_ON(!list_empty(&tgt->list));
214	kfree(tgt);
215}
216
217/*
218 * snic_tgt_del : work function to delete snic_tgt
219 */
220static void
221snic_tgt_del(struct work_struct *work)
222{
223	struct snic_tgt *tgt = container_of(work, struct snic_tgt, del_work);
224	struct Scsi_Host *shost = snic_tgt_to_shost(tgt);
225
226	if (tgt->flags & SNIC_TGT_SCAN_PENDING)
227		scsi_flush_work(shost);
228
229	/* Block IOs on child devices, stops new IOs */
230	scsi_target_block(&tgt->dev);
231
232	/* Cleanup IOs */
233	snic_tgt_scsi_abort_io(tgt);
234
235	/* Unblock IOs now, to flush if there are any. */
236	scsi_target_unblock(&tgt->dev, SDEV_TRANSPORT_OFFLINE);
237
238	/* Delete SCSI Target and sdevs */
239	scsi_remove_target(&tgt->dev);  /* ?? */
240	device_del(&tgt->dev);
241	put_device(&tgt->dev);
242} /* end of snic_tgt_del */
243
244/* snic_tgt_create: checks for existence of snic_tgt, if it doesn't
245 * it creates one.
246 */
247static struct snic_tgt *
248snic_tgt_create(struct snic *snic, struct snic_tgt_id *tgtid)
249{
250	struct snic_tgt *tgt = NULL;
251	unsigned long flags;
252	int ret;
253
254	tgt = snic_tgt_lookup(snic, tgtid);
255	if (tgt) {
256		/* update the information if required */
257		return tgt;
258	}
259
260	tgt = kzalloc(sizeof(*tgt), GFP_KERNEL);
261	if (!tgt) {
262		SNIC_HOST_ERR(snic->shost, "Failure to allocate snic_tgt.\n");
263		ret = -ENOMEM;
264
265		return tgt;
266	}
267
268	INIT_LIST_HEAD(&tgt->list);
269	tgt->id = le32_to_cpu(tgtid->tgt_id);
270	tgt->channel = 0;
271
272	SNIC_BUG_ON(le16_to_cpu(tgtid->tgt_type) > SNIC_TGT_SAN);
273	tgt->tdata.typ = le16_to_cpu(tgtid->tgt_type);
274
275	/*
276	 * Plugging into SML Device Tree
277	 */
278	tgt->tdata.disc_id = 0;
279	tgt->state = SNIC_TGT_STAT_INIT;
280	device_initialize(&tgt->dev);
281	tgt->dev.parent = get_device(&snic->shost->shost_gendev);
282	tgt->dev.release = snic_tgt_dev_release;
283	INIT_WORK(&tgt->scan_work, snic_scsi_scan_tgt);
284	INIT_WORK(&tgt->del_work, snic_tgt_del);
285	switch (tgt->tdata.typ) {
286	case SNIC_TGT_DAS:
287		dev_set_name(&tgt->dev, "snic_das_tgt:%d:%d-%d",
288			     snic->shost->host_no, tgt->channel, tgt->id);
289		break;
290
291	case SNIC_TGT_SAN:
292		dev_set_name(&tgt->dev, "snic_san_tgt:%d:%d-%d",
293			     snic->shost->host_no, tgt->channel, tgt->id);
294		break;
295
296	default:
297		SNIC_HOST_INFO(snic->shost, "Target type Unknown Detected.\n");
298		dev_set_name(&tgt->dev, "snic_das_tgt:%d:%d-%d",
299			     snic->shost->host_no, tgt->channel, tgt->id);
300		break;
301	}
302
303	spin_lock_irqsave(snic->shost->host_lock, flags);
304	list_add_tail(&tgt->list, &snic->disc.tgt_list);
305	tgt->scsi_tgt_id = snic->disc.nxt_tgt_id++;
306	tgt->state = SNIC_TGT_STAT_ONLINE;
307	spin_unlock_irqrestore(snic->shost->host_lock, flags);
308
309	SNIC_HOST_INFO(snic->shost,
310		       "Tgt %d, type = %s detected. Adding..\n",
311		       tgt->id, snic_tgt_type_to_str(tgt->tdata.typ));
312
313	ret = device_add(&tgt->dev);
314	if (ret) {
315		SNIC_HOST_ERR(snic->shost,
316			      "Snic Tgt: device_add, with err = %d\n",
317			      ret);
318
319		put_device(&snic->shost->shost_gendev);
320		kfree(tgt);
321		tgt = NULL;
322
323		return tgt;
324	}
325
326	SNIC_HOST_INFO(snic->shost, "Scanning %s.\n", dev_name(&tgt->dev));
327
328	scsi_queue_work(snic->shost, &tgt->scan_work);
329
330	return tgt;
331} /* end of snic_tgt_create */
332
333/* Handler for discovery */
334void
335snic_handle_tgt_disc(struct work_struct *work)
336{
337	struct snic *snic = container_of(work, struct snic, tgt_work);
338	struct snic_tgt_id *tgtid = NULL;
339	struct snic_tgt *tgt = NULL;
340	unsigned long flags;
341	int i;
342
343	spin_lock_irqsave(&snic->snic_lock, flags);
344	if (snic->in_remove) {
345		spin_unlock_irqrestore(&snic->snic_lock, flags);
346		kfree(snic->disc.rtgt_info);
347
348		return;
349	}
350	spin_unlock_irqrestore(&snic->snic_lock, flags);
351
352	mutex_lock(&snic->disc.mutex);
353	/* Discover triggered during disc in progress */
354	if (snic->disc.req_cnt) {
355		snic->disc.state = SNIC_DISC_DONE;
356		snic->disc.req_cnt = 0;
357		mutex_unlock(&snic->disc.mutex);
358		kfree(snic->disc.rtgt_info);
359		snic->disc.rtgt_info = NULL;
360
361		SNIC_HOST_INFO(snic->shost, "tgt_disc: Discovery restart.\n");
362		/* Start Discovery Again */
363		snic_disc_start(snic);
364
365		return;
366	}
367
368	tgtid = (struct snic_tgt_id *)snic->disc.rtgt_info;
369
370	SNIC_BUG_ON(snic->disc.rtgt_cnt == 0 || tgtid == NULL);
371
372	for (i = 0; i < snic->disc.rtgt_cnt; i++) {
373		tgt = snic_tgt_create(snic, &tgtid[i]);
374		if (!tgt) {
375			int buf_sz = snic->disc.rtgt_cnt * sizeof(*tgtid);
376
377			SNIC_HOST_ERR(snic->shost, "Failed to create tgt.\n");
378			snic_hex_dump("rpt_tgt_rsp", (char *)tgtid, buf_sz);
379			break;
380		}
381	}
382
383	snic->disc.rtgt_info = NULL;
384	snic->disc.state = SNIC_DISC_DONE;
385	mutex_unlock(&snic->disc.mutex);
386
387	SNIC_HOST_INFO(snic->shost, "Discovery Completed.\n");
388
389	kfree(tgtid);
390} /* end of snic_handle_tgt_disc */
391
392
393int
394snic_report_tgt_cmpl_handler(struct snic *snic, struct snic_fw_req *fwreq)
395{
396
397	u8 typ, cmpl_stat;
398	u32 cmnd_id, hid, tgt_cnt = 0;
399	ulong ctx;
400	struct snic_req_info *rqi = NULL;
401	struct snic_tgt_id *tgtid;
402	int i, ret = 0;
403
404	snic_io_hdr_dec(&fwreq->hdr, &typ, &cmpl_stat, &cmnd_id, &hid, &ctx);
405	rqi = (struct snic_req_info *) ctx;
406	tgtid = (struct snic_tgt_id *) rqi->sge_va;
407
408	tgt_cnt = le32_to_cpu(fwreq->u.rpt_tgts_cmpl.tgt_cnt);
409	if (tgt_cnt == 0) {
410		SNIC_HOST_ERR(snic->shost, "No Targets Found on this host.\n");
411		ret = 1;
412
413		goto end;
414	}
415
416	/* printing list of targets here */
417	SNIC_HOST_INFO(snic->shost, "Target Count = %d\n", tgt_cnt);
418
419	SNIC_BUG_ON(tgt_cnt > snic->fwinfo.max_tgts);
420
421	for (i = 0; i < tgt_cnt; i++)
422		SNIC_HOST_INFO(snic->shost,
423			       "Tgt id = 0x%x\n",
424			       le32_to_cpu(tgtid[i].tgt_id));
425
426	/*
427	 * Queue work for further processing,
428	 * Response Buffer Memory is freed after creating targets
429	 */
430	snic->disc.rtgt_cnt = tgt_cnt;
431	snic->disc.rtgt_info = (u8 *) tgtid;
432	queue_work(snic_glob->event_q, &snic->tgt_work);
433	ret = 0;
434
435end:
436	/* Unmap Response Buffer */
437	snic_pci_unmap_rsp_buf(snic, rqi);
438	if (ret)
439		kfree(tgtid);
440
441	rqi->sge_va = 0;
442	snic_release_untagged_req(snic, rqi);
443
444	return ret;
445} /* end of snic_report_tgt_cmpl_handler */
446
447/* Discovery init fn */
448void
449snic_disc_init(struct snic_disc *disc)
450{
451	INIT_LIST_HEAD(&disc->tgt_list);
452	mutex_init(&disc->mutex);
453	disc->disc_id = 0;
454	disc->nxt_tgt_id = 0;
455	disc->state = SNIC_DISC_INIT;
456	disc->req_cnt = 0;
457	disc->rtgt_cnt = 0;
458	disc->rtgt_info = NULL;
459	disc->cb = NULL;
460} /* end of snic_disc_init */
461
462/* Discovery, uninit fn */
463void
464snic_disc_term(struct snic *snic)
465{
466	struct snic_disc *disc = &snic->disc;
467
468	mutex_lock(&disc->mutex);
469	if (disc->req_cnt) {
470		disc->req_cnt = 0;
471		SNIC_SCSI_DBG(snic->shost, "Terminating Discovery.\n");
472	}
473	mutex_unlock(&disc->mutex);
474}
475
476/*
477 * snic_disc_start: Discovery Start ...
478 */
479int
480snic_disc_start(struct snic *snic)
481{
482	struct snic_disc *disc = &snic->disc;
483	int ret = 0;
484
485	SNIC_SCSI_DBG(snic->shost, "Discovery Start.\n");
486
487	mutex_lock(&disc->mutex);
488	if (disc->state == SNIC_DISC_PENDING) {
489		disc->req_cnt++;
490		mutex_unlock(&disc->mutex);
491
492		return ret;
493	}
494	disc->state = SNIC_DISC_PENDING;
495	mutex_unlock(&disc->mutex);
496
497	ret = snic_queue_report_tgt_req(snic);
498	if (ret)
499		SNIC_HOST_INFO(snic->shost, "Discovery Failed, err=%d.\n", ret);
500
501	return ret;
502} /* end of snic_disc_start */
503
504/*
505 * snic_disc_work :
506 */
507void
508snic_handle_disc(struct work_struct *work)
509{
510	struct snic *snic = container_of(work, struct snic, disc_work);
511	int ret = 0;
512
513	SNIC_HOST_INFO(snic->shost, "disc_work: Discovery\n");
514
515	ret = snic_disc_start(snic);
516	if (ret)
517		goto disc_err;
518
519disc_err:
520	SNIC_HOST_ERR(snic->shost,
521		      "disc_work: Discovery Failed w/ err = %d\n",
522		      ret);
523} /* end of snic_disc_work */
524
525/*
526 * snic_tgt_del_all : cleanup all snic targets
527 * Called on unbinding the interface
528 */
529void
530snic_tgt_del_all(struct snic *snic)
531{
532	struct snic_tgt *tgt = NULL;
533	struct list_head *cur, *nxt;
534	unsigned long flags;
535
536	mutex_lock(&snic->disc.mutex);
537	spin_lock_irqsave(snic->shost->host_lock, flags);
538
539	list_for_each_safe(cur, nxt, &snic->disc.tgt_list) {
540		tgt = list_entry(cur, struct snic_tgt, list);
541		tgt->state = SNIC_TGT_STAT_DEL;
542		list_del_init(&tgt->list);
543		SNIC_HOST_INFO(snic->shost, "Tgt %d q'ing for del\n", tgt->id);
544		queue_work(snic_glob->event_q, &tgt->del_work);
545		tgt = NULL;
546	}
547	spin_unlock_irqrestore(snic->shost->host_lock, flags);
548
549	scsi_flush_work(snic->shost);
550	mutex_unlock(&snic->disc.mutex);
551} /* end of snic_tgt_del_all */
552