xref: /linux/drivers/scsi/snic/snic_main.c (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright 2014 Cisco Systems, Inc.  All rights reserved.
3 
4 #include <linux/module.h>
5 #include <linux/mempool.h>
6 #include <linux/string.h>
7 #include <linux/slab.h>
8 #include <linux/errno.h>
9 #include <linux/init.h>
10 #include <linux/pci.h>
11 #include <linux/skbuff.h>
12 #include <linux/interrupt.h>
13 #include <linux/spinlock.h>
14 #include <linux/workqueue.h>
15 #include <scsi/scsi_host.h>
16 #include <scsi/scsi_tcq.h>
17 
18 #include "snic.h"
19 #include "snic_fwint.h"
20 
21 #define PCI_DEVICE_ID_CISCO_SNIC	0x0046
22 
23 /* Supported devices by snic module */
24 static struct pci_device_id snic_id_table[] = {
25 	{PCI_DEVICE(0x1137, PCI_DEVICE_ID_CISCO_SNIC) },
26 	{ 0, }	/* end of table */
27 };
28 
29 unsigned int snic_log_level = 0x0;
30 module_param(snic_log_level, int, S_IRUGO|S_IWUSR);
31 MODULE_PARM_DESC(snic_log_level, "bitmask for snic logging levels");
32 
33 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
34 unsigned int snic_trace_max_pages = 16;
35 module_param(snic_trace_max_pages, uint, S_IRUGO|S_IWUSR);
36 MODULE_PARM_DESC(snic_trace_max_pages,
37 		"Total allocated memory pages for snic trace buffer");
38 
39 #endif
40 unsigned int snic_max_qdepth = SNIC_DFLT_QUEUE_DEPTH;
41 module_param(snic_max_qdepth, uint, S_IRUGO | S_IWUSR);
42 MODULE_PARM_DESC(snic_max_qdepth, "Queue depth to report for each LUN");
43 
44 /*
45  * snic_slave_alloc : callback function to SCSI Mid Layer, called on
46  * scsi device initialization.
47  */
48 static int
49 snic_slave_alloc(struct scsi_device *sdev)
50 {
51 	struct snic_tgt *tgt = starget_to_tgt(scsi_target(sdev));
52 
53 	if (!tgt || snic_tgt_chkready(tgt))
54 		return -ENXIO;
55 
56 	return 0;
57 }
58 
59 /*
60  * snic_slave_configure : callback function to SCSI Mid Layer, called on
61  * scsi device initialization.
62  */
63 static int
64 snic_slave_configure(struct scsi_device *sdev)
65 {
66 	struct snic *snic = shost_priv(sdev->host);
67 	u32 qdepth = 0, max_ios = 0;
68 	int tmo = SNIC_DFLT_CMD_TIMEOUT * HZ;
69 
70 	/* Set Queue Depth */
71 	max_ios = snic_max_qdepth;
72 	qdepth = min_t(u32, max_ios, SNIC_MAX_QUEUE_DEPTH);
73 	scsi_change_queue_depth(sdev, qdepth);
74 
75 	if (snic->fwinfo.io_tmo > 1)
76 		tmo = snic->fwinfo.io_tmo * HZ;
77 
78 	/* FW requires extended timeouts */
79 	blk_queue_rq_timeout(sdev->request_queue, tmo);
80 
81 	return 0;
82 }
83 
84 static int
85 snic_change_queue_depth(struct scsi_device *sdev, int qdepth)
86 {
87 	struct snic *snic = shost_priv(sdev->host);
88 	int qsz = 0;
89 
90 	qsz = min_t(u32, qdepth, SNIC_MAX_QUEUE_DEPTH);
91 	if (qsz < sdev->queue_depth)
92 		atomic64_inc(&snic->s_stats.misc.qsz_rampdown);
93 	else if (qsz > sdev->queue_depth)
94 		atomic64_inc(&snic->s_stats.misc.qsz_rampup);
95 
96 	atomic64_set(&snic->s_stats.misc.last_qsz, sdev->queue_depth);
97 
98 	scsi_change_queue_depth(sdev, qsz);
99 
100 	return sdev->queue_depth;
101 }
102 
103 static const struct scsi_host_template snic_host_template = {
104 	.module = THIS_MODULE,
105 	.name = SNIC_DRV_NAME,
106 	.queuecommand = snic_queuecommand,
107 	.eh_abort_handler = snic_abort_cmd,
108 	.eh_device_reset_handler = snic_device_reset,
109 	.eh_host_reset_handler = snic_host_reset,
110 	.slave_alloc = snic_slave_alloc,
111 	.slave_configure = snic_slave_configure,
112 	.change_queue_depth = snic_change_queue_depth,
113 	.this_id = -1,
114 	.cmd_per_lun = SNIC_DFLT_QUEUE_DEPTH,
115 	.can_queue = SNIC_MAX_IO_REQ,
116 	.sg_tablesize = SNIC_MAX_SG_DESC_CNT,
117 	.max_sectors = 0x800,
118 	.shost_groups = snic_host_groups,
119 	.track_queue_depth = 1,
120 	.cmd_size = sizeof(struct snic_internal_io_state),
121 	.proc_name = "snic_scsi",
122 };
123 
124 /*
125  * snic_handle_link_event : Handles link events such as link up/down/error
126  */
127 void
128 snic_handle_link_event(struct snic *snic)
129 {
130 	unsigned long flags;
131 
132 	spin_lock_irqsave(&snic->snic_lock, flags);
133 	if (snic->stop_link_events) {
134 		spin_unlock_irqrestore(&snic->snic_lock, flags);
135 
136 		return;
137 	}
138 	spin_unlock_irqrestore(&snic->snic_lock, flags);
139 
140 	queue_work(snic_glob->event_q, &snic->link_work);
141 } /* end of snic_handle_link_event */
142 
143 /*
144  * snic_notify_set : sets notification area
145  * This notification area is to receive events from fw
146  * Note: snic supports only MSIX interrupts, in which we can just call
147  *  svnic_dev_notify_set directly
148  */
149 static int
150 snic_notify_set(struct snic *snic)
151 {
152 	int ret = 0;
153 	enum vnic_dev_intr_mode intr_mode;
154 
155 	intr_mode = svnic_dev_get_intr_mode(snic->vdev);
156 
157 	if (intr_mode == VNIC_DEV_INTR_MODE_MSIX) {
158 		ret = svnic_dev_notify_set(snic->vdev, SNIC_MSIX_ERR_NOTIFY);
159 	} else {
160 		SNIC_HOST_ERR(snic->shost,
161 			      "Interrupt mode should be setup before devcmd notify set %d\n",
162 			      intr_mode);
163 		ret = -1;
164 	}
165 
166 	return ret;
167 } /* end of snic_notify_set */
168 
169 /*
170  * snic_dev_wait : polls vnic open status.
171  */
172 static int
173 snic_dev_wait(struct vnic_dev *vdev,
174 		int (*start)(struct vnic_dev *, int),
175 		int (*finished)(struct vnic_dev *, int *),
176 		int arg)
177 {
178 	unsigned long time;
179 	int ret, done;
180 	int retry_cnt = 0;
181 
182 	ret = start(vdev, arg);
183 	if (ret)
184 		return ret;
185 
186 	/*
187 	 * Wait for func to complete...2 seconds max.
188 	 *
189 	 * Sometimes schedule_timeout_uninterruptible take long	time
190 	 * to wakeup, which results skipping retry. The retry counter
191 	 * ensures to retry at least two times.
192 	 */
193 	time = jiffies + (HZ * 2);
194 	do {
195 		ret = finished(vdev, &done);
196 		if (ret)
197 			return ret;
198 
199 		if (done)
200 			return 0;
201 		schedule_timeout_uninterruptible(HZ/10);
202 		++retry_cnt;
203 	} while (time_after(time, jiffies) || (retry_cnt < 3));
204 
205 	return -ETIMEDOUT;
206 } /* end of snic_dev_wait */
207 
208 /*
209  * snic_cleanup: called by snic_remove
210  * Stops the snic device, masks all interrupts, Completed CQ entries are
211  * drained. Posted WQ/RQ/Copy-WQ entries are cleanup
212  */
213 static int
214 snic_cleanup(struct snic *snic)
215 {
216 	unsigned int i;
217 	int ret;
218 
219 	svnic_dev_disable(snic->vdev);
220 	for (i = 0; i < snic->intr_count; i++)
221 		svnic_intr_mask(&snic->intr[i]);
222 
223 	for (i = 0; i < snic->wq_count; i++) {
224 		ret = svnic_wq_disable(&snic->wq[i]);
225 		if (ret)
226 			return ret;
227 	}
228 
229 	/* Clean up completed IOs */
230 	snic_fwcq_cmpl_handler(snic, -1);
231 
232 	snic_wq_cmpl_handler(snic, -1);
233 
234 	/* Clean up the IOs that have not completed */
235 	for (i = 0; i < snic->wq_count; i++)
236 		svnic_wq_clean(&snic->wq[i], snic_free_wq_buf);
237 
238 	for (i = 0; i < snic->cq_count; i++)
239 		svnic_cq_clean(&snic->cq[i]);
240 
241 	for (i = 0; i < snic->intr_count; i++)
242 		svnic_intr_clean(&snic->intr[i]);
243 
244 	/* Cleanup snic specific requests */
245 	snic_free_all_untagged_reqs(snic);
246 
247 	/* Cleanup Pending SCSI commands */
248 	snic_shutdown_scsi_cleanup(snic);
249 
250 	for (i = 0; i < SNIC_REQ_MAX_CACHES; i++)
251 		mempool_destroy(snic->req_pool[i]);
252 
253 	return 0;
254 } /* end of snic_cleanup */
255 
256 
257 static void
258 snic_iounmap(struct snic *snic)
259 {
260 	if (snic->bar0.vaddr)
261 		iounmap(snic->bar0.vaddr);
262 }
263 
264 /*
265  * snic_vdev_open_done : polls for svnic_dev_open cmd completion.
266  */
267 static int
268 snic_vdev_open_done(struct vnic_dev *vdev, int *done)
269 {
270 	struct snic *snic = svnic_dev_priv(vdev);
271 	int ret;
272 	int nretries = 5;
273 
274 	do {
275 		ret = svnic_dev_open_done(vdev, done);
276 		if (ret == 0)
277 			break;
278 
279 		SNIC_HOST_INFO(snic->shost, "VNIC_DEV_OPEN Timedout.\n");
280 	} while (nretries--);
281 
282 	return ret;
283 } /* end of snic_vdev_open_done */
284 
285 /*
286  * snic_add_host : registers scsi host with ML
287  */
288 static int
289 snic_add_host(struct Scsi_Host *shost, struct pci_dev *pdev)
290 {
291 	int ret = 0;
292 
293 	ret = scsi_add_host(shost, &pdev->dev);
294 	if (ret) {
295 		SNIC_HOST_ERR(shost,
296 			      "snic: scsi_add_host failed. %d\n",
297 			      ret);
298 
299 		return ret;
300 	}
301 
302 	SNIC_BUG_ON(shost->work_q != NULL);
303 	snprintf(shost->work_q_name, sizeof(shost->work_q_name), "scsi_wq_%d",
304 		 shost->host_no);
305 	shost->work_q = create_singlethread_workqueue(shost->work_q_name);
306 	if (!shost->work_q) {
307 		SNIC_HOST_ERR(shost, "Failed to Create ScsiHost wq.\n");
308 
309 		ret = -ENOMEM;
310 	}
311 
312 	return ret;
313 } /* end of snic_add_host */
314 
315 static void
316 snic_del_host(struct Scsi_Host *shost)
317 {
318 	if (!shost->work_q)
319 		return;
320 
321 	destroy_workqueue(shost->work_q);
322 	shost->work_q = NULL;
323 	scsi_remove_host(shost);
324 }
325 
326 int
327 snic_get_state(struct snic *snic)
328 {
329 	return atomic_read(&snic->state);
330 }
331 
332 void
333 snic_set_state(struct snic *snic, enum snic_state state)
334 {
335 	SNIC_HOST_INFO(snic->shost, "snic state change from %s to %s\n",
336 		       snic_state_to_str(snic_get_state(snic)),
337 		       snic_state_to_str(state));
338 
339 	atomic_set(&snic->state, state);
340 }
341 
342 /*
343  * snic_probe : Initialize the snic interface.
344  */
345 static int
346 snic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
347 {
348 	struct Scsi_Host *shost;
349 	struct snic *snic;
350 	mempool_t *pool;
351 	unsigned long flags;
352 	u32 max_ios = 0;
353 	int ret, i;
354 
355 	/* Device Information */
356 	SNIC_INFO("snic device %4x:%4x:%4x:%4x: ",
357 		  pdev->vendor, pdev->device, pdev->subsystem_vendor,
358 		  pdev->subsystem_device);
359 
360 	SNIC_INFO("snic device bus %x: slot %x: fn %x\n",
361 		  pdev->bus->number, PCI_SLOT(pdev->devfn),
362 		  PCI_FUNC(pdev->devfn));
363 
364 	/*
365 	 * Allocate SCSI Host and setup association between host, and snic
366 	 */
367 	shost = scsi_host_alloc(&snic_host_template, sizeof(struct snic));
368 	if (!shost) {
369 		SNIC_ERR("Unable to alloc scsi_host\n");
370 		ret = -ENOMEM;
371 
372 		goto prob_end;
373 	}
374 	snic = shost_priv(shost);
375 	snic->shost = shost;
376 
377 	snprintf(snic->name, sizeof(snic->name) - 1, "%s%d", SNIC_DRV_NAME,
378 		 shost->host_no);
379 
380 	SNIC_HOST_INFO(shost,
381 		       "snic%d = %p shost = %p device bus %x: slot %x: fn %x\n",
382 		       shost->host_no, snic, shost, pdev->bus->number,
383 		       PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
384 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
385 	/* Per snic debugfs init */
386 	snic_stats_debugfs_init(snic);
387 #endif
388 
389 	/* Setup PCI Resources */
390 	pci_set_drvdata(pdev, snic);
391 	snic->pdev = pdev;
392 
393 	ret = pci_enable_device(pdev);
394 	if (ret) {
395 		SNIC_HOST_ERR(shost,
396 			      "Cannot enable PCI Resources, aborting : %d\n",
397 			      ret);
398 
399 		goto err_free_snic;
400 	}
401 
402 	ret = pci_request_regions(pdev, SNIC_DRV_NAME);
403 	if (ret) {
404 		SNIC_HOST_ERR(shost,
405 			      "Cannot obtain PCI Resources, aborting : %d\n",
406 			      ret);
407 
408 		goto err_pci_disable;
409 	}
410 
411 	pci_set_master(pdev);
412 
413 	/*
414 	 * Query PCI Controller on system for DMA addressing
415 	 * limitation for the device. Try 43-bit first, and
416 	 * fail to 32-bit.
417 	 */
418 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(43));
419 	if (ret) {
420 		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
421 		if (ret) {
422 			SNIC_HOST_ERR(shost,
423 				      "No Usable DMA Configuration, aborting %d\n",
424 				      ret);
425 			goto err_rel_regions;
426 		}
427 	}
428 
429 	/* Map vNIC resources from BAR0 */
430 	if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
431 		SNIC_HOST_ERR(shost, "BAR0 not memory mappable aborting.\n");
432 
433 		ret = -ENODEV;
434 		goto err_rel_regions;
435 	}
436 
437 	snic->bar0.vaddr = pci_iomap(pdev, 0, 0);
438 	if (!snic->bar0.vaddr) {
439 		SNIC_HOST_ERR(shost,
440 			      "Cannot memory map BAR0 res hdr aborting.\n");
441 
442 		ret = -ENODEV;
443 		goto err_rel_regions;
444 	}
445 
446 	snic->bar0.bus_addr = pci_resource_start(pdev, 0);
447 	snic->bar0.len = pci_resource_len(pdev, 0);
448 	SNIC_BUG_ON(snic->bar0.bus_addr == 0);
449 
450 	/* Devcmd2 Resource Allocation and Initialization */
451 	snic->vdev = svnic_dev_alloc_discover(NULL, snic, pdev, &snic->bar0, 1);
452 	if (!snic->vdev) {
453 		SNIC_HOST_ERR(shost, "vNIC Resource Discovery Failed.\n");
454 
455 		ret = -ENODEV;
456 		goto err_iounmap;
457 	}
458 
459 	ret = svnic_dev_cmd_init(snic->vdev, 0);
460 	if (ret) {
461 		SNIC_HOST_INFO(shost, "Devcmd2 Init Failed. err = %d\n", ret);
462 
463 		goto err_vnic_unreg;
464 	}
465 
466 	ret = snic_dev_wait(snic->vdev, svnic_dev_open, snic_vdev_open_done, 0);
467 	if (ret) {
468 		SNIC_HOST_ERR(shost,
469 			      "vNIC dev open failed, aborting. %d\n",
470 			      ret);
471 
472 		goto err_vnic_unreg;
473 	}
474 
475 	ret = svnic_dev_init(snic->vdev, 0);
476 	if (ret) {
477 		SNIC_HOST_ERR(shost,
478 			      "vNIC dev init failed. aborting. %d\n",
479 			      ret);
480 
481 		goto err_dev_close;
482 	}
483 
484 	/* Get vNIC information */
485 	ret = snic_get_vnic_config(snic);
486 	if (ret) {
487 		SNIC_HOST_ERR(shost,
488 			      "Get vNIC configuration failed, aborting. %d\n",
489 			      ret);
490 
491 		goto err_dev_close;
492 	}
493 
494 	/* Configure Maximum Outstanding IO reqs */
495 	max_ios = snic->config.io_throttle_count;
496 	if (max_ios != SNIC_UCSM_DFLT_THROTTLE_CNT_BLD)
497 		shost->can_queue = min_t(u32, SNIC_MAX_IO_REQ,
498 					 max_t(u32, SNIC_MIN_IO_REQ, max_ios));
499 
500 	snic->max_tag_id = shost->can_queue;
501 
502 	shost->max_lun = snic->config.luns_per_tgt;
503 	shost->max_id = SNIC_MAX_TARGET;
504 
505 	shost->max_cmd_len = MAX_COMMAND_SIZE; /*defined in scsi_cmnd.h*/
506 
507 	snic_get_res_counts(snic);
508 
509 	/*
510 	 * Assumption: Only MSIx is supported
511 	 */
512 	ret = snic_set_intr_mode(snic);
513 	if (ret) {
514 		SNIC_HOST_ERR(shost,
515 			      "Failed to set intr mode aborting. %d\n",
516 			      ret);
517 
518 		goto err_dev_close;
519 	}
520 
521 	ret = snic_alloc_vnic_res(snic);
522 	if (ret) {
523 		SNIC_HOST_ERR(shost,
524 			      "Failed to alloc vNIC resources aborting. %d\n",
525 			      ret);
526 
527 		goto err_clear_intr;
528 	}
529 
530 	/* Initialize specific lists */
531 	INIT_LIST_HEAD(&snic->list);
532 
533 	/*
534 	 * spl_cmd_list for maintaining snic specific cmds
535 	 * such as EXCH_VER_REQ, REPORT_TARGETS etc
536 	 */
537 	INIT_LIST_HEAD(&snic->spl_cmd_list);
538 	spin_lock_init(&snic->spl_cmd_lock);
539 
540 	/* initialize all snic locks */
541 	spin_lock_init(&snic->snic_lock);
542 
543 	for (i = 0; i < SNIC_WQ_MAX; i++)
544 		spin_lock_init(&snic->wq_lock[i]);
545 
546 	for (i = 0; i < SNIC_IO_LOCKS; i++)
547 		spin_lock_init(&snic->io_req_lock[i]);
548 
549 	pool = mempool_create_slab_pool(2,
550 				snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
551 	if (!pool) {
552 		SNIC_HOST_ERR(shost, "dflt sgl pool creation failed\n");
553 
554 		ret = -ENOMEM;
555 		goto err_free_res;
556 	}
557 
558 	snic->req_pool[SNIC_REQ_CACHE_DFLT_SGL] = pool;
559 
560 	pool = mempool_create_slab_pool(2,
561 				snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
562 	if (!pool) {
563 		SNIC_HOST_ERR(shost, "max sgl pool creation failed\n");
564 
565 		ret = -ENOMEM;
566 		goto err_free_dflt_sgl_pool;
567 	}
568 
569 	snic->req_pool[SNIC_REQ_CACHE_MAX_SGL] = pool;
570 
571 	pool = mempool_create_slab_pool(2,
572 				snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
573 	if (!pool) {
574 		SNIC_HOST_ERR(shost, "snic tmreq info pool creation failed.\n");
575 
576 		ret = -ENOMEM;
577 		goto err_free_max_sgl_pool;
578 	}
579 
580 	snic->req_pool[SNIC_REQ_TM_CACHE] = pool;
581 
582 	/* Initialize snic state */
583 	atomic_set(&snic->state, SNIC_INIT);
584 
585 	atomic_set(&snic->ios_inflight, 0);
586 
587 	/* Setup notification buffer area */
588 	ret = snic_notify_set(snic);
589 	if (ret) {
590 		SNIC_HOST_ERR(shost,
591 			      "Failed to alloc notify buffer aborting. %d\n",
592 			      ret);
593 
594 		goto err_free_tmreq_pool;
595 	}
596 
597 	spin_lock_irqsave(&snic_glob->snic_list_lock, flags);
598 	list_add_tail(&snic->list, &snic_glob->snic_list);
599 	spin_unlock_irqrestore(&snic_glob->snic_list_lock, flags);
600 
601 	snic_disc_init(&snic->disc);
602 	INIT_WORK(&snic->tgt_work, snic_handle_tgt_disc);
603 	INIT_WORK(&snic->disc_work, snic_handle_disc);
604 	INIT_WORK(&snic->link_work, snic_handle_link);
605 
606 	/* Enable all queues */
607 	for (i = 0; i < snic->wq_count; i++)
608 		svnic_wq_enable(&snic->wq[i]);
609 
610 	ret = svnic_dev_enable_wait(snic->vdev);
611 	if (ret) {
612 		SNIC_HOST_ERR(shost,
613 			      "vNIC dev enable failed w/ error %d\n",
614 			      ret);
615 
616 		goto err_vdev_enable;
617 	}
618 
619 	ret = snic_request_intr(snic);
620 	if (ret) {
621 		SNIC_HOST_ERR(shost, "Unable to request irq. %d\n", ret);
622 
623 		goto err_req_intr;
624 	}
625 
626 	for (i = 0; i < snic->intr_count; i++)
627 		svnic_intr_unmask(&snic->intr[i]);
628 
629 	/* Get snic params */
630 	ret = snic_get_conf(snic);
631 	if (ret) {
632 		SNIC_HOST_ERR(shost,
633 			      "Failed to get snic io config from FW w err %d\n",
634 			      ret);
635 
636 		goto err_get_conf;
637 	}
638 
639 	/*
640 	 * Initialization done with PCI system, hardware, firmware.
641 	 * Add shost to SCSI
642 	 */
643 	ret = snic_add_host(shost, pdev);
644 	if (ret) {
645 		SNIC_HOST_ERR(shost,
646 			      "Adding scsi host Failed ... exiting. %d\n",
647 			      ret);
648 
649 		goto err_get_conf;
650 	}
651 
652 	snic_set_state(snic, SNIC_ONLINE);
653 
654 	ret = snic_disc_start(snic);
655 	if (ret) {
656 		SNIC_HOST_ERR(shost, "snic_probe:Discovery Failed w err = %d\n",
657 			      ret);
658 
659 		goto err_get_conf;
660 	}
661 
662 	SNIC_HOST_INFO(shost, "SNIC Device Probe Successful.\n");
663 
664 	return 0;
665 
666 err_get_conf:
667 	snic_free_all_untagged_reqs(snic);
668 
669 	for (i = 0; i < snic->intr_count; i++)
670 		svnic_intr_mask(&snic->intr[i]);
671 
672 	snic_free_intr(snic);
673 
674 err_req_intr:
675 	svnic_dev_disable(snic->vdev);
676 
677 err_vdev_enable:
678 	svnic_dev_notify_unset(snic->vdev);
679 
680 	for (i = 0; i < snic->wq_count; i++) {
681 		int rc = 0;
682 
683 		rc = svnic_wq_disable(&snic->wq[i]);
684 		if (rc) {
685 			SNIC_HOST_ERR(shost,
686 				      "WQ Disable Failed w/ err = %d\n", rc);
687 
688 			 break;
689 		}
690 	}
691 	snic_del_host(snic->shost);
692 
693 err_free_tmreq_pool:
694 	mempool_destroy(snic->req_pool[SNIC_REQ_TM_CACHE]);
695 
696 err_free_max_sgl_pool:
697 	mempool_destroy(snic->req_pool[SNIC_REQ_CACHE_MAX_SGL]);
698 
699 err_free_dflt_sgl_pool:
700 	mempool_destroy(snic->req_pool[SNIC_REQ_CACHE_DFLT_SGL]);
701 
702 err_free_res:
703 	snic_free_vnic_res(snic);
704 
705 err_clear_intr:
706 	snic_clear_intr_mode(snic);
707 
708 err_dev_close:
709 	svnic_dev_close(snic->vdev);
710 
711 err_vnic_unreg:
712 	svnic_dev_unregister(snic->vdev);
713 
714 err_iounmap:
715 	snic_iounmap(snic);
716 
717 err_rel_regions:
718 	pci_release_regions(pdev);
719 
720 err_pci_disable:
721 	pci_disable_device(pdev);
722 
723 err_free_snic:
724 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
725 	snic_stats_debugfs_remove(snic);
726 #endif
727 	scsi_host_put(shost);
728 	pci_set_drvdata(pdev, NULL);
729 
730 prob_end:
731 	SNIC_INFO("sNIC device : bus %d: slot %d: fn %d Registration Failed.\n",
732 		  pdev->bus->number, PCI_SLOT(pdev->devfn),
733 		  PCI_FUNC(pdev->devfn));
734 
735 	return ret;
736 } /* end of snic_probe */
737 
738 
739 /*
740  * snic_remove : invoked on unbinding the interface to cleanup the
741  * resources allocated in snic_probe on initialization.
742  */
743 static void
744 snic_remove(struct pci_dev *pdev)
745 {
746 	struct snic *snic = pci_get_drvdata(pdev);
747 	unsigned long flags;
748 
749 	if (!snic) {
750 		SNIC_INFO("sNIC dev: bus %d slot %d fn %d snic inst is null.\n",
751 			  pdev->bus->number, PCI_SLOT(pdev->devfn),
752 			  PCI_FUNC(pdev->devfn));
753 
754 		return;
755 	}
756 
757 	/*
758 	 * Mark state so that the workqueue thread stops forwarding
759 	 * received frames and link events. ISR and other threads
760 	 * that can queue work items will also stop creating work
761 	 * items on the snic workqueue
762 	 */
763 	snic_set_state(snic, SNIC_OFFLINE);
764 	spin_lock_irqsave(&snic->snic_lock, flags);
765 	snic->stop_link_events = 1;
766 	spin_unlock_irqrestore(&snic->snic_lock, flags);
767 
768 	flush_workqueue(snic_glob->event_q);
769 	snic_disc_term(snic);
770 
771 	spin_lock_irqsave(&snic->snic_lock, flags);
772 	snic->in_remove = 1;
773 	spin_unlock_irqrestore(&snic->snic_lock, flags);
774 
775 	/*
776 	 * This stops the snic device, masks all interrupts, Completed
777 	 * CQ entries are drained. Posted WQ/RQ/Copy-WQ entries are
778 	 * cleanup
779 	 */
780 	snic_cleanup(snic);
781 
782 	spin_lock_irqsave(&snic_glob->snic_list_lock, flags);
783 	list_del(&snic->list);
784 	spin_unlock_irqrestore(&snic_glob->snic_list_lock, flags);
785 
786 	snic_tgt_del_all(snic);
787 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
788 	snic_stats_debugfs_remove(snic);
789 #endif
790 	snic_del_host(snic->shost);
791 
792 	svnic_dev_notify_unset(snic->vdev);
793 	snic_free_intr(snic);
794 	snic_free_vnic_res(snic);
795 	snic_clear_intr_mode(snic);
796 	svnic_dev_close(snic->vdev);
797 	svnic_dev_unregister(snic->vdev);
798 	snic_iounmap(snic);
799 	pci_release_regions(pdev);
800 	pci_disable_device(pdev);
801 	pci_set_drvdata(pdev, NULL);
802 
803 	/* this frees Scsi_Host and snic memory (continuous chunk) */
804 	scsi_host_put(snic->shost);
805 } /* end of snic_remove */
806 
807 
808 struct snic_global *snic_glob;
809 
810 /*
811  * snic_global_data_init: Initialize SNIC Global Data
812  * Notes: All the global lists, variables should be part of global data
813  * this helps in debugging.
814  */
815 static int
816 snic_global_data_init(void)
817 {
818 	int ret = 0;
819 	struct kmem_cache *cachep;
820 	ssize_t len = 0;
821 
822 	snic_glob = kzalloc(sizeof(*snic_glob), GFP_KERNEL);
823 
824 	if (!snic_glob) {
825 		SNIC_ERR("Failed to allocate Global Context.\n");
826 
827 		ret = -ENOMEM;
828 		goto gdi_end;
829 	}
830 
831 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
832 	/* Debugfs related Initialization */
833 	/* Create debugfs entries for snic */
834 	snic_debugfs_init();
835 
836 	/* Trace related Initialization */
837 	/* Allocate memory for trace buffer */
838 	ret = snic_trc_init();
839 	if (ret < 0) {
840 		SNIC_ERR("Trace buffer init failed, SNIC tracing disabled\n");
841 		snic_trc_free();
842 		/* continue even if it fails */
843 	}
844 
845 #endif
846 	INIT_LIST_HEAD(&snic_glob->snic_list);
847 	spin_lock_init(&snic_glob->snic_list_lock);
848 
849 	/* Create a cache for allocation of snic_host_req+default size ESGLs */
850 	len = sizeof(struct snic_req_info);
851 	len += sizeof(struct snic_host_req) + sizeof(struct snic_dflt_sgl);
852 	cachep = kmem_cache_create("snic_req_dfltsgl", len, SNIC_SG_DESC_ALIGN,
853 				   SLAB_HWCACHE_ALIGN, NULL);
854 	if (!cachep) {
855 		SNIC_ERR("Failed to create snic default sgl slab\n");
856 		ret = -ENOMEM;
857 
858 		goto err_dflt_req_slab;
859 	}
860 	snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL] = cachep;
861 
862 	/* Create a cache for allocation of max size Extended SGLs */
863 	len = sizeof(struct snic_req_info);
864 	len += sizeof(struct snic_host_req) + sizeof(struct snic_max_sgl);
865 	cachep = kmem_cache_create("snic_req_maxsgl", len, SNIC_SG_DESC_ALIGN,
866 				   SLAB_HWCACHE_ALIGN, NULL);
867 	if (!cachep) {
868 		SNIC_ERR("Failed to create snic max sgl slab\n");
869 		ret = -ENOMEM;
870 
871 		goto err_max_req_slab;
872 	}
873 	snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL] = cachep;
874 
875 	len = sizeof(struct snic_host_req);
876 	cachep = kmem_cache_create("snic_req_maxsgl", len, SNIC_SG_DESC_ALIGN,
877 				   SLAB_HWCACHE_ALIGN, NULL);
878 	if (!cachep) {
879 		SNIC_ERR("Failed to create snic tm req slab\n");
880 		ret = -ENOMEM;
881 
882 		goto err_tmreq_slab;
883 	}
884 	snic_glob->req_cache[SNIC_REQ_TM_CACHE] = cachep;
885 
886 	/* snic_event queue */
887 	snic_glob->event_q = create_singlethread_workqueue("snic_event_wq");
888 	if (!snic_glob->event_q) {
889 		SNIC_ERR("snic event queue create failed\n");
890 		ret = -ENOMEM;
891 
892 		goto err_eventq;
893 	}
894 
895 	return ret;
896 
897 err_eventq:
898 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
899 
900 err_tmreq_slab:
901 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
902 
903 err_max_req_slab:
904 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
905 
906 err_dflt_req_slab:
907 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
908 	snic_trc_free();
909 	snic_debugfs_term();
910 #endif
911 	kfree(snic_glob);
912 	snic_glob = NULL;
913 
914 gdi_end:
915 	return ret;
916 } /* end of snic_glob_init */
917 
918 /*
919  * snic_global_data_cleanup : Frees SNIC Global Data
920  */
921 static void
922 snic_global_data_cleanup(void)
923 {
924 	SNIC_BUG_ON(snic_glob == NULL);
925 
926 	destroy_workqueue(snic_glob->event_q);
927 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
928 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
929 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
930 
931 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
932 	/* Freeing Trace Resources */
933 	snic_trc_free();
934 
935 	/* Freeing Debugfs Resources */
936 	snic_debugfs_term();
937 #endif
938 	kfree(snic_glob);
939 	snic_glob = NULL;
940 } /* end of snic_glob_cleanup */
941 
942 static struct pci_driver snic_driver = {
943 	.name = SNIC_DRV_NAME,
944 	.id_table = snic_id_table,
945 	.probe = snic_probe,
946 	.remove = snic_remove,
947 };
948 
949 static int __init
950 snic_init_module(void)
951 {
952 	int ret = 0;
953 
954 #ifndef __x86_64__
955 	SNIC_INFO("SNIC Driver is supported only for x86_64 platforms!\n");
956 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
957 #endif
958 
959 	SNIC_INFO("%s, ver %s\n", SNIC_DRV_DESCRIPTION, SNIC_DRV_VERSION);
960 
961 	ret = snic_global_data_init();
962 	if (ret) {
963 		SNIC_ERR("Failed to Initialize Global Data.\n");
964 
965 		return ret;
966 	}
967 
968 	ret = pci_register_driver(&snic_driver);
969 	if (ret < 0) {
970 		SNIC_ERR("PCI driver register error\n");
971 
972 		goto err_pci_reg;
973 	}
974 
975 	return ret;
976 
977 err_pci_reg:
978 	snic_global_data_cleanup();
979 
980 	return ret;
981 }
982 
983 static void __exit
984 snic_cleanup_module(void)
985 {
986 	pci_unregister_driver(&snic_driver);
987 	snic_global_data_cleanup();
988 }
989 
990 module_init(snic_init_module);
991 module_exit(snic_cleanup_module);
992 
993 MODULE_LICENSE("GPL v2");
994 MODULE_DESCRIPTION(SNIC_DRV_DESCRIPTION);
995 MODULE_VERSION(SNIC_DRV_VERSION);
996 MODULE_DEVICE_TABLE(pci, snic_id_table);
997 MODULE_AUTHOR("Narsimhulu Musini <nmusini@cisco.com>, "
998 	      "Sesidhar Baddela <sebaddel@cisco.com>");
999