xref: /openbmc/linux/drivers/scsi/snic/snic_main.c (revision ccb01374)
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/module.h>
19 #include <linux/mempool.h>
20 #include <linux/string.h>
21 #include <linux/slab.h>
22 #include <linux/errno.h>
23 #include <linux/init.h>
24 #include <linux/pci.h>
25 #include <linux/skbuff.h>
26 #include <linux/interrupt.h>
27 #include <linux/spinlock.h>
28 #include <linux/workqueue.h>
29 #include <scsi/scsi_host.h>
30 #include <scsi/scsi_tcq.h>
31 
32 #include "snic.h"
33 #include "snic_fwint.h"
34 
35 #define PCI_DEVICE_ID_CISCO_SNIC	0x0046
36 
37 /* Supported devices by snic module */
38 static struct pci_device_id snic_id_table[] = {
39 	{PCI_DEVICE(0x1137, PCI_DEVICE_ID_CISCO_SNIC) },
40 	{ 0, }	/* end of table */
41 };
42 
43 unsigned int snic_log_level = 0x0;
44 module_param(snic_log_level, int, S_IRUGO|S_IWUSR);
45 MODULE_PARM_DESC(snic_log_level, "bitmask for snic logging levels");
46 
47 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
48 unsigned int snic_trace_max_pages = 16;
49 module_param(snic_trace_max_pages, uint, S_IRUGO|S_IWUSR);
50 MODULE_PARM_DESC(snic_trace_max_pages,
51 		"Total allocated memory pages for snic trace buffer");
52 
53 #endif
54 unsigned int snic_max_qdepth = SNIC_DFLT_QUEUE_DEPTH;
55 module_param(snic_max_qdepth, uint, S_IRUGO | S_IWUSR);
56 MODULE_PARM_DESC(snic_max_qdepth, "Queue depth to report for each LUN");
57 
58 /*
59  * snic_slave_alloc : callback function to SCSI Mid Layer, called on
60  * scsi device initialization.
61  */
62 static int
63 snic_slave_alloc(struct scsi_device *sdev)
64 {
65 	struct snic_tgt *tgt = starget_to_tgt(scsi_target(sdev));
66 
67 	if (!tgt || snic_tgt_chkready(tgt))
68 		return -ENXIO;
69 
70 	return 0;
71 }
72 
73 /*
74  * snic_slave_configure : callback function to SCSI Mid Layer, called on
75  * scsi device initialization.
76  */
77 static int
78 snic_slave_configure(struct scsi_device *sdev)
79 {
80 	struct snic *snic = shost_priv(sdev->host);
81 	u32 qdepth = 0, max_ios = 0;
82 	int tmo = SNIC_DFLT_CMD_TIMEOUT * HZ;
83 
84 	/* Set Queue Depth */
85 	max_ios = snic_max_qdepth;
86 	qdepth = min_t(u32, max_ios, SNIC_MAX_QUEUE_DEPTH);
87 	scsi_change_queue_depth(sdev, qdepth);
88 
89 	if (snic->fwinfo.io_tmo > 1)
90 		tmo = snic->fwinfo.io_tmo * HZ;
91 
92 	/* FW requires extended timeouts */
93 	blk_queue_rq_timeout(sdev->request_queue, tmo);
94 
95 	return 0;
96 }
97 
98 static int
99 snic_change_queue_depth(struct scsi_device *sdev, int qdepth)
100 {
101 	struct snic *snic = shost_priv(sdev->host);
102 	int qsz = 0;
103 
104 	qsz = min_t(u32, qdepth, SNIC_MAX_QUEUE_DEPTH);
105 	if (qsz < sdev->queue_depth)
106 		atomic64_inc(&snic->s_stats.misc.qsz_rampdown);
107 	else if (qsz > sdev->queue_depth)
108 		atomic64_inc(&snic->s_stats.misc.qsz_rampup);
109 
110 	atomic64_set(&snic->s_stats.misc.last_qsz, sdev->queue_depth);
111 
112 	scsi_change_queue_depth(sdev, qsz);
113 
114 	return sdev->queue_depth;
115 }
116 
117 static struct scsi_host_template snic_host_template = {
118 	.module = THIS_MODULE,
119 	.name = SNIC_DRV_NAME,
120 	.queuecommand = snic_queuecommand,
121 	.eh_abort_handler = snic_abort_cmd,
122 	.eh_device_reset_handler = snic_device_reset,
123 	.eh_host_reset_handler = snic_host_reset,
124 	.slave_alloc = snic_slave_alloc,
125 	.slave_configure = snic_slave_configure,
126 	.change_queue_depth = snic_change_queue_depth,
127 	.this_id = -1,
128 	.cmd_per_lun = SNIC_DFLT_QUEUE_DEPTH,
129 	.can_queue = SNIC_MAX_IO_REQ,
130 	.sg_tablesize = SNIC_MAX_SG_DESC_CNT,
131 	.max_sectors = 0x800,
132 	.shost_attrs = snic_attrs,
133 	.track_queue_depth = 1,
134 	.cmd_size = sizeof(struct snic_internal_io_state),
135 	.proc_name = "snic_scsi",
136 };
137 
138 /*
139  * snic_handle_link_event : Handles link events such as link up/down/error
140  */
141 void
142 snic_handle_link_event(struct snic *snic)
143 {
144 	unsigned long flags;
145 
146 	spin_lock_irqsave(&snic->snic_lock, flags);
147 	if (snic->stop_link_events) {
148 		spin_unlock_irqrestore(&snic->snic_lock, flags);
149 
150 		return;
151 	}
152 	spin_unlock_irqrestore(&snic->snic_lock, flags);
153 
154 	queue_work(snic_glob->event_q, &snic->link_work);
155 } /* end of snic_handle_link_event */
156 
157 /*
158  * snic_notify_set : sets notification area
159  * This notification area is to receive events from fw
160  * Note: snic supports only MSIX interrupts, in which we can just call
161  *  svnic_dev_notify_set directly
162  */
163 static int
164 snic_notify_set(struct snic *snic)
165 {
166 	int ret = 0;
167 	enum vnic_dev_intr_mode intr_mode;
168 
169 	intr_mode = svnic_dev_get_intr_mode(snic->vdev);
170 
171 	if (intr_mode == VNIC_DEV_INTR_MODE_MSIX) {
172 		ret = svnic_dev_notify_set(snic->vdev, SNIC_MSIX_ERR_NOTIFY);
173 	} else {
174 		SNIC_HOST_ERR(snic->shost,
175 			      "Interrupt mode should be setup before devcmd notify set %d\n",
176 			      intr_mode);
177 		ret = -1;
178 	}
179 
180 	return ret;
181 } /* end of snic_notify_set */
182 
183 /*
184  * snic_dev_wait : polls vnic open status.
185  */
186 static int
187 snic_dev_wait(struct vnic_dev *vdev,
188 		int (*start)(struct vnic_dev *, int),
189 		int (*finished)(struct vnic_dev *, int *),
190 		int arg)
191 {
192 	unsigned long time;
193 	int ret, done;
194 	int retry_cnt = 0;
195 
196 	ret = start(vdev, arg);
197 	if (ret)
198 		return ret;
199 
200 	/*
201 	 * Wait for func to complete...2 seconds max.
202 	 *
203 	 * Sometimes schedule_timeout_uninterruptible take long	time
204 	 * to wakeup, which results skipping retry. The retry counter
205 	 * ensures to retry at least two times.
206 	 */
207 	time = jiffies + (HZ * 2);
208 	do {
209 		ret = finished(vdev, &done);
210 		if (ret)
211 			return ret;
212 
213 		if (done)
214 			return 0;
215 		schedule_timeout_uninterruptible(HZ/10);
216 		++retry_cnt;
217 	} while (time_after(time, jiffies) || (retry_cnt < 3));
218 
219 	return -ETIMEDOUT;
220 } /* end of snic_dev_wait */
221 
222 /*
223  * snic_cleanup: called by snic_remove
224  * Stops the snic device, masks all interrupts, Completed CQ entries are
225  * drained. Posted WQ/RQ/Copy-WQ entries are cleanup
226  */
227 static int
228 snic_cleanup(struct snic *snic)
229 {
230 	unsigned int i;
231 	int ret;
232 
233 	svnic_dev_disable(snic->vdev);
234 	for (i = 0; i < snic->intr_count; i++)
235 		svnic_intr_mask(&snic->intr[i]);
236 
237 	for (i = 0; i < snic->wq_count; i++) {
238 		ret = svnic_wq_disable(&snic->wq[i]);
239 		if (ret)
240 			return ret;
241 	}
242 
243 	/* Clean up completed IOs */
244 	snic_fwcq_cmpl_handler(snic, -1);
245 
246 	snic_wq_cmpl_handler(snic, -1);
247 
248 	/* Clean up the IOs that have not completed */
249 	for (i = 0; i < snic->wq_count; i++)
250 		svnic_wq_clean(&snic->wq[i], snic_free_wq_buf);
251 
252 	for (i = 0; i < snic->cq_count; i++)
253 		svnic_cq_clean(&snic->cq[i]);
254 
255 	for (i = 0; i < snic->intr_count; i++)
256 		svnic_intr_clean(&snic->intr[i]);
257 
258 	/* Cleanup snic specific requests */
259 	snic_free_all_untagged_reqs(snic);
260 
261 	/* Cleanup Pending SCSI commands */
262 	snic_shutdown_scsi_cleanup(snic);
263 
264 	for (i = 0; i < SNIC_REQ_MAX_CACHES; i++)
265 		mempool_destroy(snic->req_pool[i]);
266 
267 	return 0;
268 } /* end of snic_cleanup */
269 
270 
271 static void
272 snic_iounmap(struct snic *snic)
273 {
274 	if (snic->bar0.vaddr)
275 		iounmap(snic->bar0.vaddr);
276 }
277 
278 /*
279  * snic_vdev_open_done : polls for svnic_dev_open cmd completion.
280  */
281 static int
282 snic_vdev_open_done(struct vnic_dev *vdev, int *done)
283 {
284 	struct snic *snic = svnic_dev_priv(vdev);
285 	int ret;
286 	int nretries = 5;
287 
288 	do {
289 		ret = svnic_dev_open_done(vdev, done);
290 		if (ret == 0)
291 			break;
292 
293 		SNIC_HOST_INFO(snic->shost, "VNIC_DEV_OPEN Timedout.\n");
294 	} while (nretries--);
295 
296 	return ret;
297 } /* end of snic_vdev_open_done */
298 
299 /*
300  * snic_add_host : registers scsi host with ML
301  */
302 static int
303 snic_add_host(struct Scsi_Host *shost, struct pci_dev *pdev)
304 {
305 	int ret = 0;
306 
307 	ret = scsi_add_host(shost, &pdev->dev);
308 	if (ret) {
309 		SNIC_HOST_ERR(shost,
310 			      "snic: scsi_add_host failed. %d\n",
311 			      ret);
312 
313 		return ret;
314 	}
315 
316 	SNIC_BUG_ON(shost->work_q != NULL);
317 	snprintf(shost->work_q_name, sizeof(shost->work_q_name), "scsi_wq_%d",
318 		 shost->host_no);
319 	shost->work_q = create_singlethread_workqueue(shost->work_q_name);
320 	if (!shost->work_q) {
321 		SNIC_HOST_ERR(shost, "Failed to Create ScsiHost wq.\n");
322 
323 		ret = -ENOMEM;
324 	}
325 
326 	return ret;
327 } /* end of snic_add_host */
328 
329 static void
330 snic_del_host(struct Scsi_Host *shost)
331 {
332 	if (!shost->work_q)
333 		return;
334 
335 	destroy_workqueue(shost->work_q);
336 	shost->work_q = NULL;
337 	scsi_remove_host(shost);
338 }
339 
340 int
341 snic_get_state(struct snic *snic)
342 {
343 	return atomic_read(&snic->state);
344 }
345 
346 void
347 snic_set_state(struct snic *snic, enum snic_state state)
348 {
349 	SNIC_HOST_INFO(snic->shost, "snic state change from %s to %s\n",
350 		       snic_state_to_str(snic_get_state(snic)),
351 		       snic_state_to_str(state));
352 
353 	atomic_set(&snic->state, state);
354 }
355 
356 /*
357  * snic_probe : Initialize the snic interface.
358  */
359 static int
360 snic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
361 {
362 	struct Scsi_Host *shost;
363 	struct snic *snic;
364 	mempool_t *pool;
365 	unsigned long flags;
366 	u32 max_ios = 0;
367 	int ret, i;
368 
369 	/* Device Information */
370 	SNIC_INFO("snic device %4x:%4x:%4x:%4x: ",
371 		  pdev->vendor, pdev->device, pdev->subsystem_vendor,
372 		  pdev->subsystem_device);
373 
374 	SNIC_INFO("snic device bus %x: slot %x: fn %x\n",
375 		  pdev->bus->number, PCI_SLOT(pdev->devfn),
376 		  PCI_FUNC(pdev->devfn));
377 
378 	/*
379 	 * Allocate SCSI Host and setup association between host, and snic
380 	 */
381 	shost = scsi_host_alloc(&snic_host_template, sizeof(struct snic));
382 	if (!shost) {
383 		SNIC_ERR("Unable to alloc scsi_host\n");
384 		ret = -ENOMEM;
385 
386 		goto prob_end;
387 	}
388 	snic = shost_priv(shost);
389 	snic->shost = shost;
390 
391 	snprintf(snic->name, sizeof(snic->name) - 1, "%s%d", SNIC_DRV_NAME,
392 		 shost->host_no);
393 
394 	SNIC_HOST_INFO(shost,
395 		       "snic%d = %p shost = %p device bus %x: slot %x: fn %x\n",
396 		       shost->host_no, snic, shost, pdev->bus->number,
397 		       PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
398 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
399 	/* Per snic debugfs init */
400 	ret = snic_stats_debugfs_init(snic);
401 	if (ret) {
402 		SNIC_HOST_ERR(snic->shost,
403 			      "Failed to initialize debugfs stats\n");
404 		snic_stats_debugfs_remove(snic);
405 	}
406 #endif
407 
408 	/* Setup PCI Resources */
409 	pci_set_drvdata(pdev, snic);
410 	snic->pdev = pdev;
411 
412 	ret = pci_enable_device(pdev);
413 	if (ret) {
414 		SNIC_HOST_ERR(shost,
415 			      "Cannot enable PCI Resources, aborting : %d\n",
416 			      ret);
417 
418 		goto err_free_snic;
419 	}
420 
421 	ret = pci_request_regions(pdev, SNIC_DRV_NAME);
422 	if (ret) {
423 		SNIC_HOST_ERR(shost,
424 			      "Cannot obtain PCI Resources, aborting : %d\n",
425 			      ret);
426 
427 		goto err_pci_disable;
428 	}
429 
430 	pci_set_master(pdev);
431 
432 	/*
433 	 * Query PCI Controller on system for DMA addressing
434 	 * limitation for the device. Try 43-bit first, and
435 	 * fail to 32-bit.
436 	 */
437 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(43));
438 	if (ret) {
439 		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
440 		if (ret) {
441 			SNIC_HOST_ERR(shost,
442 				      "No Usable DMA Configuration, aborting %d\n",
443 				      ret);
444 			goto err_rel_regions;
445 		}
446 	}
447 
448 	/* Map vNIC resources from BAR0 */
449 	if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
450 		SNIC_HOST_ERR(shost, "BAR0 not memory mappable aborting.\n");
451 
452 		ret = -ENODEV;
453 		goto err_rel_regions;
454 	}
455 
456 	snic->bar0.vaddr = pci_iomap(pdev, 0, 0);
457 	if (!snic->bar0.vaddr) {
458 		SNIC_HOST_ERR(shost,
459 			      "Cannot memory map BAR0 res hdr aborting.\n");
460 
461 		ret = -ENODEV;
462 		goto err_rel_regions;
463 	}
464 
465 	snic->bar0.bus_addr = pci_resource_start(pdev, 0);
466 	snic->bar0.len = pci_resource_len(pdev, 0);
467 	SNIC_BUG_ON(snic->bar0.bus_addr == 0);
468 
469 	/* Devcmd2 Resource Allocation and Initialization */
470 	snic->vdev = svnic_dev_alloc_discover(NULL, snic, pdev, &snic->bar0, 1);
471 	if (!snic->vdev) {
472 		SNIC_HOST_ERR(shost, "vNIC Resource Discovery Failed.\n");
473 
474 		ret = -ENODEV;
475 		goto err_iounmap;
476 	}
477 
478 	ret = svnic_dev_cmd_init(snic->vdev, 0);
479 	if (ret) {
480 		SNIC_HOST_INFO(shost, "Devcmd2 Init Failed. err = %d\n", ret);
481 
482 		goto err_vnic_unreg;
483 	}
484 
485 	ret = snic_dev_wait(snic->vdev, svnic_dev_open, snic_vdev_open_done, 0);
486 	if (ret) {
487 		SNIC_HOST_ERR(shost,
488 			      "vNIC dev open failed, aborting. %d\n",
489 			      ret);
490 
491 		goto err_vnic_unreg;
492 	}
493 
494 	ret = svnic_dev_init(snic->vdev, 0);
495 	if (ret) {
496 		SNIC_HOST_ERR(shost,
497 			      "vNIC dev init failed. aborting. %d\n",
498 			      ret);
499 
500 		goto err_dev_close;
501 	}
502 
503 	/* Get vNIC information */
504 	ret = snic_get_vnic_config(snic);
505 	if (ret) {
506 		SNIC_HOST_ERR(shost,
507 			      "Get vNIC configuration failed, aborting. %d\n",
508 			      ret);
509 
510 		goto err_dev_close;
511 	}
512 
513 	/* Configure Maximum Outstanding IO reqs */
514 	max_ios = snic->config.io_throttle_count;
515 	if (max_ios != SNIC_UCSM_DFLT_THROTTLE_CNT_BLD)
516 		shost->can_queue = min_t(u32, SNIC_MAX_IO_REQ,
517 					 max_t(u32, SNIC_MIN_IO_REQ, max_ios));
518 
519 	snic->max_tag_id = shost->can_queue;
520 
521 	shost->max_lun = snic->config.luns_per_tgt;
522 	shost->max_id = SNIC_MAX_TARGET;
523 
524 	shost->max_cmd_len = MAX_COMMAND_SIZE; /*defined in scsi_cmnd.h*/
525 
526 	snic_get_res_counts(snic);
527 
528 	/*
529 	 * Assumption: Only MSIx is supported
530 	 */
531 	ret = snic_set_intr_mode(snic);
532 	if (ret) {
533 		SNIC_HOST_ERR(shost,
534 			      "Failed to set intr mode aborting. %d\n",
535 			      ret);
536 
537 		goto err_dev_close;
538 	}
539 
540 	ret = snic_alloc_vnic_res(snic);
541 	if (ret) {
542 		SNIC_HOST_ERR(shost,
543 			      "Failed to alloc vNIC resources aborting. %d\n",
544 			      ret);
545 
546 		goto err_clear_intr;
547 	}
548 
549 	/* Initialize specific lists */
550 	INIT_LIST_HEAD(&snic->list);
551 
552 	/*
553 	 * spl_cmd_list for maintaining snic specific cmds
554 	 * such as EXCH_VER_REQ, REPORT_TARGETS etc
555 	 */
556 	INIT_LIST_HEAD(&snic->spl_cmd_list);
557 	spin_lock_init(&snic->spl_cmd_lock);
558 
559 	/* initialize all snic locks */
560 	spin_lock_init(&snic->snic_lock);
561 
562 	for (i = 0; i < SNIC_WQ_MAX; i++)
563 		spin_lock_init(&snic->wq_lock[i]);
564 
565 	for (i = 0; i < SNIC_IO_LOCKS; i++)
566 		spin_lock_init(&snic->io_req_lock[i]);
567 
568 	pool = mempool_create_slab_pool(2,
569 				snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
570 	if (!pool) {
571 		SNIC_HOST_ERR(shost, "dflt sgl pool creation failed\n");
572 
573 		ret = -ENOMEM;
574 		goto err_free_res;
575 	}
576 
577 	snic->req_pool[SNIC_REQ_CACHE_DFLT_SGL] = pool;
578 
579 	pool = mempool_create_slab_pool(2,
580 				snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
581 	if (!pool) {
582 		SNIC_HOST_ERR(shost, "max sgl pool creation failed\n");
583 
584 		ret = -ENOMEM;
585 		goto err_free_dflt_sgl_pool;
586 	}
587 
588 	snic->req_pool[SNIC_REQ_CACHE_MAX_SGL] = pool;
589 
590 	pool = mempool_create_slab_pool(2,
591 				snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
592 	if (!pool) {
593 		SNIC_HOST_ERR(shost, "snic tmreq info pool creation failed.\n");
594 
595 		ret = -ENOMEM;
596 		goto err_free_max_sgl_pool;
597 	}
598 
599 	snic->req_pool[SNIC_REQ_TM_CACHE] = pool;
600 
601 	/* Initialize snic state */
602 	atomic_set(&snic->state, SNIC_INIT);
603 
604 	atomic_set(&snic->ios_inflight, 0);
605 
606 	/* Setup notification buffer area */
607 	ret = snic_notify_set(snic);
608 	if (ret) {
609 		SNIC_HOST_ERR(shost,
610 			      "Failed to alloc notify buffer aborting. %d\n",
611 			      ret);
612 
613 		goto err_free_tmreq_pool;
614 	}
615 
616 	spin_lock_irqsave(&snic_glob->snic_list_lock, flags);
617 	list_add_tail(&snic->list, &snic_glob->snic_list);
618 	spin_unlock_irqrestore(&snic_glob->snic_list_lock, flags);
619 
620 	snic_disc_init(&snic->disc);
621 	INIT_WORK(&snic->tgt_work, snic_handle_tgt_disc);
622 	INIT_WORK(&snic->disc_work, snic_handle_disc);
623 	INIT_WORK(&snic->link_work, snic_handle_link);
624 
625 	/* Enable all queues */
626 	for (i = 0; i < snic->wq_count; i++)
627 		svnic_wq_enable(&snic->wq[i]);
628 
629 	ret = svnic_dev_enable_wait(snic->vdev);
630 	if (ret) {
631 		SNIC_HOST_ERR(shost,
632 			      "vNIC dev enable failed w/ error %d\n",
633 			      ret);
634 
635 		goto err_vdev_enable;
636 	}
637 
638 	ret = snic_request_intr(snic);
639 	if (ret) {
640 		SNIC_HOST_ERR(shost, "Unable to request irq. %d\n", ret);
641 
642 		goto err_req_intr;
643 	}
644 
645 	for (i = 0; i < snic->intr_count; i++)
646 		svnic_intr_unmask(&snic->intr[i]);
647 
648 	/* Get snic params */
649 	ret = snic_get_conf(snic);
650 	if (ret) {
651 		SNIC_HOST_ERR(shost,
652 			      "Failed to get snic io config from FW w err %d\n",
653 			      ret);
654 
655 		goto err_get_conf;
656 	}
657 
658 	/*
659 	 * Initialization done with PCI system, hardware, firmware.
660 	 * Add shost to SCSI
661 	 */
662 	ret = snic_add_host(shost, pdev);
663 	if (ret) {
664 		SNIC_HOST_ERR(shost,
665 			      "Adding scsi host Failed ... exiting. %d\n",
666 			      ret);
667 
668 		goto err_get_conf;
669 	}
670 
671 	snic_set_state(snic, SNIC_ONLINE);
672 
673 	ret = snic_disc_start(snic);
674 	if (ret) {
675 		SNIC_HOST_ERR(shost, "snic_probe:Discovery Failed w err = %d\n",
676 			      ret);
677 
678 		goto err_get_conf;
679 	}
680 
681 	SNIC_HOST_INFO(shost, "SNIC Device Probe Successful.\n");
682 
683 	return 0;
684 
685 err_get_conf:
686 	snic_free_all_untagged_reqs(snic);
687 
688 	for (i = 0; i < snic->intr_count; i++)
689 		svnic_intr_mask(&snic->intr[i]);
690 
691 	snic_free_intr(snic);
692 
693 err_req_intr:
694 	svnic_dev_disable(snic->vdev);
695 
696 err_vdev_enable:
697 	svnic_dev_notify_unset(snic->vdev);
698 
699 	for (i = 0; i < snic->wq_count; i++) {
700 		int rc = 0;
701 
702 		rc = svnic_wq_disable(&snic->wq[i]);
703 		if (rc) {
704 			SNIC_HOST_ERR(shost,
705 				      "WQ Disable Failed w/ err = %d\n", rc);
706 
707 			 break;
708 		}
709 	}
710 	snic_del_host(snic->shost);
711 
712 err_free_tmreq_pool:
713 	mempool_destroy(snic->req_pool[SNIC_REQ_TM_CACHE]);
714 
715 err_free_max_sgl_pool:
716 	mempool_destroy(snic->req_pool[SNIC_REQ_CACHE_MAX_SGL]);
717 
718 err_free_dflt_sgl_pool:
719 	mempool_destroy(snic->req_pool[SNIC_REQ_CACHE_DFLT_SGL]);
720 
721 err_free_res:
722 	snic_free_vnic_res(snic);
723 
724 err_clear_intr:
725 	snic_clear_intr_mode(snic);
726 
727 err_dev_close:
728 	svnic_dev_close(snic->vdev);
729 
730 err_vnic_unreg:
731 	svnic_dev_unregister(snic->vdev);
732 
733 err_iounmap:
734 	snic_iounmap(snic);
735 
736 err_rel_regions:
737 	pci_release_regions(pdev);
738 
739 err_pci_disable:
740 	pci_disable_device(pdev);
741 
742 err_free_snic:
743 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
744 	snic_stats_debugfs_remove(snic);
745 #endif
746 	scsi_host_put(shost);
747 	pci_set_drvdata(pdev, NULL);
748 
749 prob_end:
750 	SNIC_INFO("sNIC device : bus %d: slot %d: fn %d Registration Failed.\n",
751 		  pdev->bus->number, PCI_SLOT(pdev->devfn),
752 		  PCI_FUNC(pdev->devfn));
753 
754 	return ret;
755 } /* end of snic_probe */
756 
757 
758 /*
759  * snic_remove : invoked on unbinding the interface to cleanup the
760  * resources allocated in snic_probe on initialization.
761  */
762 static void
763 snic_remove(struct pci_dev *pdev)
764 {
765 	struct snic *snic = pci_get_drvdata(pdev);
766 	unsigned long flags;
767 
768 	if (!snic) {
769 		SNIC_INFO("sNIC dev: bus %d slot %d fn %d snic inst is null.\n",
770 			  pdev->bus->number, PCI_SLOT(pdev->devfn),
771 			  PCI_FUNC(pdev->devfn));
772 
773 		return;
774 	}
775 
776 	/*
777 	 * Mark state so that the workqueue thread stops forwarding
778 	 * received frames and link events. ISR and other threads
779 	 * that can queue work items will also stop creating work
780 	 * items on the snic workqueue
781 	 */
782 	snic_set_state(snic, SNIC_OFFLINE);
783 	spin_lock_irqsave(&snic->snic_lock, flags);
784 	snic->stop_link_events = 1;
785 	spin_unlock_irqrestore(&snic->snic_lock, flags);
786 
787 	flush_workqueue(snic_glob->event_q);
788 	snic_disc_term(snic);
789 
790 	spin_lock_irqsave(&snic->snic_lock, flags);
791 	snic->in_remove = 1;
792 	spin_unlock_irqrestore(&snic->snic_lock, flags);
793 
794 	/*
795 	 * This stops the snic device, masks all interrupts, Completed
796 	 * CQ entries are drained. Posted WQ/RQ/Copy-WQ entries are
797 	 * cleanup
798 	 */
799 	snic_cleanup(snic);
800 
801 	spin_lock_irqsave(&snic_glob->snic_list_lock, flags);
802 	list_del(&snic->list);
803 	spin_unlock_irqrestore(&snic_glob->snic_list_lock, flags);
804 
805 	snic_tgt_del_all(snic);
806 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
807 	snic_stats_debugfs_remove(snic);
808 #endif
809 	snic_del_host(snic->shost);
810 
811 	svnic_dev_notify_unset(snic->vdev);
812 	snic_free_intr(snic);
813 	snic_free_vnic_res(snic);
814 	snic_clear_intr_mode(snic);
815 	svnic_dev_close(snic->vdev);
816 	svnic_dev_unregister(snic->vdev);
817 	snic_iounmap(snic);
818 	pci_release_regions(pdev);
819 	pci_disable_device(pdev);
820 	pci_set_drvdata(pdev, NULL);
821 
822 	/* this frees Scsi_Host and snic memory (continuous chunk) */
823 	scsi_host_put(snic->shost);
824 } /* end of snic_remove */
825 
826 
827 struct snic_global *snic_glob;
828 
829 /*
830  * snic_global_data_init: Initialize SNIC Global Data
831  * Notes: All the global lists, variables should be part of global data
832  * this helps in debugging.
833  */
834 static int
835 snic_global_data_init(void)
836 {
837 	int ret = 0;
838 	struct kmem_cache *cachep;
839 	ssize_t len = 0;
840 
841 	snic_glob = kzalloc(sizeof(*snic_glob), GFP_KERNEL);
842 
843 	if (!snic_glob) {
844 		SNIC_ERR("Failed to allocate Global Context.\n");
845 
846 		ret = -ENOMEM;
847 		goto gdi_end;
848 	}
849 
850 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
851 	/* Debugfs related Initialization */
852 	/* Create debugfs entries for snic */
853 	ret = snic_debugfs_init();
854 	if (ret < 0) {
855 		SNIC_ERR("Failed to create sysfs dir for tracing and stats.\n");
856 		snic_debugfs_term();
857 		/* continue even if it fails */
858 	}
859 
860 	/* Trace related Initialization */
861 	/* Allocate memory for trace buffer */
862 	ret = snic_trc_init();
863 	if (ret < 0) {
864 		SNIC_ERR("Trace buffer init failed, SNIC tracing disabled\n");
865 		snic_trc_free();
866 		/* continue even if it fails */
867 	}
868 
869 #endif
870 	INIT_LIST_HEAD(&snic_glob->snic_list);
871 	spin_lock_init(&snic_glob->snic_list_lock);
872 
873 	/* Create a cache for allocation of snic_host_req+default size ESGLs */
874 	len = sizeof(struct snic_req_info);
875 	len += sizeof(struct snic_host_req) + sizeof(struct snic_dflt_sgl);
876 	cachep = kmem_cache_create("snic_req_dfltsgl", len, SNIC_SG_DESC_ALIGN,
877 				   SLAB_HWCACHE_ALIGN, NULL);
878 	if (!cachep) {
879 		SNIC_ERR("Failed to create snic default sgl slab\n");
880 		ret = -ENOMEM;
881 
882 		goto err_dflt_req_slab;
883 	}
884 	snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL] = cachep;
885 
886 	/* Create a cache for allocation of max size Extended SGLs */
887 	len = sizeof(struct snic_req_info);
888 	len += sizeof(struct snic_host_req) + sizeof(struct snic_max_sgl);
889 	cachep = kmem_cache_create("snic_req_maxsgl", len, SNIC_SG_DESC_ALIGN,
890 				   SLAB_HWCACHE_ALIGN, NULL);
891 	if (!cachep) {
892 		SNIC_ERR("Failed to create snic max sgl slab\n");
893 		ret = -ENOMEM;
894 
895 		goto err_max_req_slab;
896 	}
897 	snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL] = cachep;
898 
899 	len = sizeof(struct snic_host_req);
900 	cachep = kmem_cache_create("snic_req_maxsgl", len, SNIC_SG_DESC_ALIGN,
901 				   SLAB_HWCACHE_ALIGN, NULL);
902 	if (!cachep) {
903 		SNIC_ERR("Failed to create snic tm req slab\n");
904 		ret = -ENOMEM;
905 
906 		goto err_tmreq_slab;
907 	}
908 	snic_glob->req_cache[SNIC_REQ_TM_CACHE] = cachep;
909 
910 	/* snic_event queue */
911 	snic_glob->event_q = create_singlethread_workqueue("snic_event_wq");
912 	if (!snic_glob->event_q) {
913 		SNIC_ERR("snic event queue create failed\n");
914 		ret = -ENOMEM;
915 
916 		goto err_eventq;
917 	}
918 
919 	return ret;
920 
921 err_eventq:
922 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
923 
924 err_tmreq_slab:
925 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
926 
927 err_max_req_slab:
928 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
929 
930 err_dflt_req_slab:
931 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
932 	snic_trc_free();
933 	snic_debugfs_term();
934 #endif
935 	kfree(snic_glob);
936 	snic_glob = NULL;
937 
938 gdi_end:
939 	return ret;
940 } /* end of snic_glob_init */
941 
942 /*
943  * snic_global_data_cleanup : Frees SNIC Global Data
944  */
945 static void
946 snic_global_data_cleanup(void)
947 {
948 	SNIC_BUG_ON(snic_glob == NULL);
949 
950 	destroy_workqueue(snic_glob->event_q);
951 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
952 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
953 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
954 
955 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
956 	/* Freeing Trace Resources */
957 	snic_trc_free();
958 
959 	/* Freeing Debugfs Resources */
960 	snic_debugfs_term();
961 #endif
962 	kfree(snic_glob);
963 	snic_glob = NULL;
964 } /* end of snic_glob_cleanup */
965 
966 static struct pci_driver snic_driver = {
967 	.name = SNIC_DRV_NAME,
968 	.id_table = snic_id_table,
969 	.probe = snic_probe,
970 	.remove = snic_remove,
971 };
972 
973 static int __init
974 snic_init_module(void)
975 {
976 	int ret = 0;
977 
978 #ifndef __x86_64__
979 	SNIC_INFO("SNIC Driver is supported only for x86_64 platforms!\n");
980 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
981 #endif
982 
983 	SNIC_INFO("%s, ver %s\n", SNIC_DRV_DESCRIPTION, SNIC_DRV_VERSION);
984 
985 	ret = snic_global_data_init();
986 	if (ret) {
987 		SNIC_ERR("Failed to Initialize Global Data.\n");
988 
989 		return ret;
990 	}
991 
992 	ret = pci_register_driver(&snic_driver);
993 	if (ret < 0) {
994 		SNIC_ERR("PCI driver register error\n");
995 
996 		goto err_pci_reg;
997 	}
998 
999 	return ret;
1000 
1001 err_pci_reg:
1002 	snic_global_data_cleanup();
1003 
1004 	return ret;
1005 }
1006 
1007 static void __exit
1008 snic_cleanup_module(void)
1009 {
1010 	pci_unregister_driver(&snic_driver);
1011 	snic_global_data_cleanup();
1012 }
1013 
1014 module_init(snic_init_module);
1015 module_exit(snic_cleanup_module);
1016 
1017 MODULE_LICENSE("GPL v2");
1018 MODULE_DESCRIPTION(SNIC_DRV_DESCRIPTION);
1019 MODULE_VERSION(SNIC_DRV_VERSION);
1020 MODULE_DEVICE_TABLE(pci, snic_id_table);
1021 MODULE_AUTHOR("Narsimhulu Musini <nmusini@cisco.com>, "
1022 	      "Sesidhar Baddela <sebaddel@cisco.com>");
1023