xref: /openbmc/linux/drivers/scsi/snic/snic_main.c (revision 3ce7547e)
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_groups = snic_host_groups,
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 	snic_stats_debugfs_init(snic);
401 #endif
402 
403 	/* Setup PCI Resources */
404 	pci_set_drvdata(pdev, snic);
405 	snic->pdev = pdev;
406 
407 	ret = pci_enable_device(pdev);
408 	if (ret) {
409 		SNIC_HOST_ERR(shost,
410 			      "Cannot enable PCI Resources, aborting : %d\n",
411 			      ret);
412 
413 		goto err_free_snic;
414 	}
415 
416 	ret = pci_request_regions(pdev, SNIC_DRV_NAME);
417 	if (ret) {
418 		SNIC_HOST_ERR(shost,
419 			      "Cannot obtain PCI Resources, aborting : %d\n",
420 			      ret);
421 
422 		goto err_pci_disable;
423 	}
424 
425 	pci_set_master(pdev);
426 
427 	/*
428 	 * Query PCI Controller on system for DMA addressing
429 	 * limitation for the device. Try 43-bit first, and
430 	 * fail to 32-bit.
431 	 */
432 	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(43));
433 	if (ret) {
434 		ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
435 		if (ret) {
436 			SNIC_HOST_ERR(shost,
437 				      "No Usable DMA Configuration, aborting %d\n",
438 				      ret);
439 			goto err_rel_regions;
440 		}
441 	}
442 
443 	/* Map vNIC resources from BAR0 */
444 	if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
445 		SNIC_HOST_ERR(shost, "BAR0 not memory mappable aborting.\n");
446 
447 		ret = -ENODEV;
448 		goto err_rel_regions;
449 	}
450 
451 	snic->bar0.vaddr = pci_iomap(pdev, 0, 0);
452 	if (!snic->bar0.vaddr) {
453 		SNIC_HOST_ERR(shost,
454 			      "Cannot memory map BAR0 res hdr aborting.\n");
455 
456 		ret = -ENODEV;
457 		goto err_rel_regions;
458 	}
459 
460 	snic->bar0.bus_addr = pci_resource_start(pdev, 0);
461 	snic->bar0.len = pci_resource_len(pdev, 0);
462 	SNIC_BUG_ON(snic->bar0.bus_addr == 0);
463 
464 	/* Devcmd2 Resource Allocation and Initialization */
465 	snic->vdev = svnic_dev_alloc_discover(NULL, snic, pdev, &snic->bar0, 1);
466 	if (!snic->vdev) {
467 		SNIC_HOST_ERR(shost, "vNIC Resource Discovery Failed.\n");
468 
469 		ret = -ENODEV;
470 		goto err_iounmap;
471 	}
472 
473 	ret = svnic_dev_cmd_init(snic->vdev, 0);
474 	if (ret) {
475 		SNIC_HOST_INFO(shost, "Devcmd2 Init Failed. err = %d\n", ret);
476 
477 		goto err_vnic_unreg;
478 	}
479 
480 	ret = snic_dev_wait(snic->vdev, svnic_dev_open, snic_vdev_open_done, 0);
481 	if (ret) {
482 		SNIC_HOST_ERR(shost,
483 			      "vNIC dev open failed, aborting. %d\n",
484 			      ret);
485 
486 		goto err_vnic_unreg;
487 	}
488 
489 	ret = svnic_dev_init(snic->vdev, 0);
490 	if (ret) {
491 		SNIC_HOST_ERR(shost,
492 			      "vNIC dev init failed. aborting. %d\n",
493 			      ret);
494 
495 		goto err_dev_close;
496 	}
497 
498 	/* Get vNIC information */
499 	ret = snic_get_vnic_config(snic);
500 	if (ret) {
501 		SNIC_HOST_ERR(shost,
502 			      "Get vNIC configuration failed, aborting. %d\n",
503 			      ret);
504 
505 		goto err_dev_close;
506 	}
507 
508 	/* Configure Maximum Outstanding IO reqs */
509 	max_ios = snic->config.io_throttle_count;
510 	if (max_ios != SNIC_UCSM_DFLT_THROTTLE_CNT_BLD)
511 		shost->can_queue = min_t(u32, SNIC_MAX_IO_REQ,
512 					 max_t(u32, SNIC_MIN_IO_REQ, max_ios));
513 
514 	snic->max_tag_id = shost->can_queue;
515 
516 	shost->max_lun = snic->config.luns_per_tgt;
517 	shost->max_id = SNIC_MAX_TARGET;
518 
519 	shost->max_cmd_len = MAX_COMMAND_SIZE; /*defined in scsi_cmnd.h*/
520 
521 	snic_get_res_counts(snic);
522 
523 	/*
524 	 * Assumption: Only MSIx is supported
525 	 */
526 	ret = snic_set_intr_mode(snic);
527 	if (ret) {
528 		SNIC_HOST_ERR(shost,
529 			      "Failed to set intr mode aborting. %d\n",
530 			      ret);
531 
532 		goto err_dev_close;
533 	}
534 
535 	ret = snic_alloc_vnic_res(snic);
536 	if (ret) {
537 		SNIC_HOST_ERR(shost,
538 			      "Failed to alloc vNIC resources aborting. %d\n",
539 			      ret);
540 
541 		goto err_clear_intr;
542 	}
543 
544 	/* Initialize specific lists */
545 	INIT_LIST_HEAD(&snic->list);
546 
547 	/*
548 	 * spl_cmd_list for maintaining snic specific cmds
549 	 * such as EXCH_VER_REQ, REPORT_TARGETS etc
550 	 */
551 	INIT_LIST_HEAD(&snic->spl_cmd_list);
552 	spin_lock_init(&snic->spl_cmd_lock);
553 
554 	/* initialize all snic locks */
555 	spin_lock_init(&snic->snic_lock);
556 
557 	for (i = 0; i < SNIC_WQ_MAX; i++)
558 		spin_lock_init(&snic->wq_lock[i]);
559 
560 	for (i = 0; i < SNIC_IO_LOCKS; i++)
561 		spin_lock_init(&snic->io_req_lock[i]);
562 
563 	pool = mempool_create_slab_pool(2,
564 				snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
565 	if (!pool) {
566 		SNIC_HOST_ERR(shost, "dflt sgl pool creation failed\n");
567 
568 		ret = -ENOMEM;
569 		goto err_free_res;
570 	}
571 
572 	snic->req_pool[SNIC_REQ_CACHE_DFLT_SGL] = pool;
573 
574 	pool = mempool_create_slab_pool(2,
575 				snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
576 	if (!pool) {
577 		SNIC_HOST_ERR(shost, "max sgl pool creation failed\n");
578 
579 		ret = -ENOMEM;
580 		goto err_free_dflt_sgl_pool;
581 	}
582 
583 	snic->req_pool[SNIC_REQ_CACHE_MAX_SGL] = pool;
584 
585 	pool = mempool_create_slab_pool(2,
586 				snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
587 	if (!pool) {
588 		SNIC_HOST_ERR(shost, "snic tmreq info pool creation failed.\n");
589 
590 		ret = -ENOMEM;
591 		goto err_free_max_sgl_pool;
592 	}
593 
594 	snic->req_pool[SNIC_REQ_TM_CACHE] = pool;
595 
596 	/* Initialize snic state */
597 	atomic_set(&snic->state, SNIC_INIT);
598 
599 	atomic_set(&snic->ios_inflight, 0);
600 
601 	/* Setup notification buffer area */
602 	ret = snic_notify_set(snic);
603 	if (ret) {
604 		SNIC_HOST_ERR(shost,
605 			      "Failed to alloc notify buffer aborting. %d\n",
606 			      ret);
607 
608 		goto err_free_tmreq_pool;
609 	}
610 
611 	spin_lock_irqsave(&snic_glob->snic_list_lock, flags);
612 	list_add_tail(&snic->list, &snic_glob->snic_list);
613 	spin_unlock_irqrestore(&snic_glob->snic_list_lock, flags);
614 
615 	snic_disc_init(&snic->disc);
616 	INIT_WORK(&snic->tgt_work, snic_handle_tgt_disc);
617 	INIT_WORK(&snic->disc_work, snic_handle_disc);
618 	INIT_WORK(&snic->link_work, snic_handle_link);
619 
620 	/* Enable all queues */
621 	for (i = 0; i < snic->wq_count; i++)
622 		svnic_wq_enable(&snic->wq[i]);
623 
624 	ret = svnic_dev_enable_wait(snic->vdev);
625 	if (ret) {
626 		SNIC_HOST_ERR(shost,
627 			      "vNIC dev enable failed w/ error %d\n",
628 			      ret);
629 
630 		goto err_vdev_enable;
631 	}
632 
633 	ret = snic_request_intr(snic);
634 	if (ret) {
635 		SNIC_HOST_ERR(shost, "Unable to request irq. %d\n", ret);
636 
637 		goto err_req_intr;
638 	}
639 
640 	for (i = 0; i < snic->intr_count; i++)
641 		svnic_intr_unmask(&snic->intr[i]);
642 
643 	/* Get snic params */
644 	ret = snic_get_conf(snic);
645 	if (ret) {
646 		SNIC_HOST_ERR(shost,
647 			      "Failed to get snic io config from FW w err %d\n",
648 			      ret);
649 
650 		goto err_get_conf;
651 	}
652 
653 	/*
654 	 * Initialization done with PCI system, hardware, firmware.
655 	 * Add shost to SCSI
656 	 */
657 	ret = snic_add_host(shost, pdev);
658 	if (ret) {
659 		SNIC_HOST_ERR(shost,
660 			      "Adding scsi host Failed ... exiting. %d\n",
661 			      ret);
662 
663 		goto err_get_conf;
664 	}
665 
666 	snic_set_state(snic, SNIC_ONLINE);
667 
668 	ret = snic_disc_start(snic);
669 	if (ret) {
670 		SNIC_HOST_ERR(shost, "snic_probe:Discovery Failed w err = %d\n",
671 			      ret);
672 
673 		goto err_get_conf;
674 	}
675 
676 	SNIC_HOST_INFO(shost, "SNIC Device Probe Successful.\n");
677 
678 	return 0;
679 
680 err_get_conf:
681 	snic_free_all_untagged_reqs(snic);
682 
683 	for (i = 0; i < snic->intr_count; i++)
684 		svnic_intr_mask(&snic->intr[i]);
685 
686 	snic_free_intr(snic);
687 
688 err_req_intr:
689 	svnic_dev_disable(snic->vdev);
690 
691 err_vdev_enable:
692 	svnic_dev_notify_unset(snic->vdev);
693 
694 	for (i = 0; i < snic->wq_count; i++) {
695 		int rc = 0;
696 
697 		rc = svnic_wq_disable(&snic->wq[i]);
698 		if (rc) {
699 			SNIC_HOST_ERR(shost,
700 				      "WQ Disable Failed w/ err = %d\n", rc);
701 
702 			 break;
703 		}
704 	}
705 	snic_del_host(snic->shost);
706 
707 err_free_tmreq_pool:
708 	mempool_destroy(snic->req_pool[SNIC_REQ_TM_CACHE]);
709 
710 err_free_max_sgl_pool:
711 	mempool_destroy(snic->req_pool[SNIC_REQ_CACHE_MAX_SGL]);
712 
713 err_free_dflt_sgl_pool:
714 	mempool_destroy(snic->req_pool[SNIC_REQ_CACHE_DFLT_SGL]);
715 
716 err_free_res:
717 	snic_free_vnic_res(snic);
718 
719 err_clear_intr:
720 	snic_clear_intr_mode(snic);
721 
722 err_dev_close:
723 	svnic_dev_close(snic->vdev);
724 
725 err_vnic_unreg:
726 	svnic_dev_unregister(snic->vdev);
727 
728 err_iounmap:
729 	snic_iounmap(snic);
730 
731 err_rel_regions:
732 	pci_release_regions(pdev);
733 
734 err_pci_disable:
735 	pci_disable_device(pdev);
736 
737 err_free_snic:
738 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
739 	snic_stats_debugfs_remove(snic);
740 #endif
741 	scsi_host_put(shost);
742 	pci_set_drvdata(pdev, NULL);
743 
744 prob_end:
745 	SNIC_INFO("sNIC device : bus %d: slot %d: fn %d Registration Failed.\n",
746 		  pdev->bus->number, PCI_SLOT(pdev->devfn),
747 		  PCI_FUNC(pdev->devfn));
748 
749 	return ret;
750 } /* end of snic_probe */
751 
752 
753 /*
754  * snic_remove : invoked on unbinding the interface to cleanup the
755  * resources allocated in snic_probe on initialization.
756  */
757 static void
758 snic_remove(struct pci_dev *pdev)
759 {
760 	struct snic *snic = pci_get_drvdata(pdev);
761 	unsigned long flags;
762 
763 	if (!snic) {
764 		SNIC_INFO("sNIC dev: bus %d slot %d fn %d snic inst is null.\n",
765 			  pdev->bus->number, PCI_SLOT(pdev->devfn),
766 			  PCI_FUNC(pdev->devfn));
767 
768 		return;
769 	}
770 
771 	/*
772 	 * Mark state so that the workqueue thread stops forwarding
773 	 * received frames and link events. ISR and other threads
774 	 * that can queue work items will also stop creating work
775 	 * items on the snic workqueue
776 	 */
777 	snic_set_state(snic, SNIC_OFFLINE);
778 	spin_lock_irqsave(&snic->snic_lock, flags);
779 	snic->stop_link_events = 1;
780 	spin_unlock_irqrestore(&snic->snic_lock, flags);
781 
782 	flush_workqueue(snic_glob->event_q);
783 	snic_disc_term(snic);
784 
785 	spin_lock_irqsave(&snic->snic_lock, flags);
786 	snic->in_remove = 1;
787 	spin_unlock_irqrestore(&snic->snic_lock, flags);
788 
789 	/*
790 	 * This stops the snic device, masks all interrupts, Completed
791 	 * CQ entries are drained. Posted WQ/RQ/Copy-WQ entries are
792 	 * cleanup
793 	 */
794 	snic_cleanup(snic);
795 
796 	spin_lock_irqsave(&snic_glob->snic_list_lock, flags);
797 	list_del(&snic->list);
798 	spin_unlock_irqrestore(&snic_glob->snic_list_lock, flags);
799 
800 	snic_tgt_del_all(snic);
801 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
802 	snic_stats_debugfs_remove(snic);
803 #endif
804 	snic_del_host(snic->shost);
805 
806 	svnic_dev_notify_unset(snic->vdev);
807 	snic_free_intr(snic);
808 	snic_free_vnic_res(snic);
809 	snic_clear_intr_mode(snic);
810 	svnic_dev_close(snic->vdev);
811 	svnic_dev_unregister(snic->vdev);
812 	snic_iounmap(snic);
813 	pci_release_regions(pdev);
814 	pci_disable_device(pdev);
815 	pci_set_drvdata(pdev, NULL);
816 
817 	/* this frees Scsi_Host and snic memory (continuous chunk) */
818 	scsi_host_put(snic->shost);
819 } /* end of snic_remove */
820 
821 
822 struct snic_global *snic_glob;
823 
824 /*
825  * snic_global_data_init: Initialize SNIC Global Data
826  * Notes: All the global lists, variables should be part of global data
827  * this helps in debugging.
828  */
829 static int
830 snic_global_data_init(void)
831 {
832 	int ret = 0;
833 	struct kmem_cache *cachep;
834 	ssize_t len = 0;
835 
836 	snic_glob = kzalloc(sizeof(*snic_glob), GFP_KERNEL);
837 
838 	if (!snic_glob) {
839 		SNIC_ERR("Failed to allocate Global Context.\n");
840 
841 		ret = -ENOMEM;
842 		goto gdi_end;
843 	}
844 
845 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
846 	/* Debugfs related Initialization */
847 	/* Create debugfs entries for snic */
848 	snic_debugfs_init();
849 
850 	/* Trace related Initialization */
851 	/* Allocate memory for trace buffer */
852 	ret = snic_trc_init();
853 	if (ret < 0) {
854 		SNIC_ERR("Trace buffer init failed, SNIC tracing disabled\n");
855 		snic_trc_free();
856 		/* continue even if it fails */
857 	}
858 
859 #endif
860 	INIT_LIST_HEAD(&snic_glob->snic_list);
861 	spin_lock_init(&snic_glob->snic_list_lock);
862 
863 	/* Create a cache for allocation of snic_host_req+default size ESGLs */
864 	len = sizeof(struct snic_req_info);
865 	len += sizeof(struct snic_host_req) + sizeof(struct snic_dflt_sgl);
866 	cachep = kmem_cache_create("snic_req_dfltsgl", len, SNIC_SG_DESC_ALIGN,
867 				   SLAB_HWCACHE_ALIGN, NULL);
868 	if (!cachep) {
869 		SNIC_ERR("Failed to create snic default sgl slab\n");
870 		ret = -ENOMEM;
871 
872 		goto err_dflt_req_slab;
873 	}
874 	snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL] = cachep;
875 
876 	/* Create a cache for allocation of max size Extended SGLs */
877 	len = sizeof(struct snic_req_info);
878 	len += sizeof(struct snic_host_req) + sizeof(struct snic_max_sgl);
879 	cachep = kmem_cache_create("snic_req_maxsgl", len, SNIC_SG_DESC_ALIGN,
880 				   SLAB_HWCACHE_ALIGN, NULL);
881 	if (!cachep) {
882 		SNIC_ERR("Failed to create snic max sgl slab\n");
883 		ret = -ENOMEM;
884 
885 		goto err_max_req_slab;
886 	}
887 	snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL] = cachep;
888 
889 	len = sizeof(struct snic_host_req);
890 	cachep = kmem_cache_create("snic_req_maxsgl", len, SNIC_SG_DESC_ALIGN,
891 				   SLAB_HWCACHE_ALIGN, NULL);
892 	if (!cachep) {
893 		SNIC_ERR("Failed to create snic tm req slab\n");
894 		ret = -ENOMEM;
895 
896 		goto err_tmreq_slab;
897 	}
898 	snic_glob->req_cache[SNIC_REQ_TM_CACHE] = cachep;
899 
900 	/* snic_event queue */
901 	snic_glob->event_q = create_singlethread_workqueue("snic_event_wq");
902 	if (!snic_glob->event_q) {
903 		SNIC_ERR("snic event queue create failed\n");
904 		ret = -ENOMEM;
905 
906 		goto err_eventq;
907 	}
908 
909 	return ret;
910 
911 err_eventq:
912 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
913 
914 err_tmreq_slab:
915 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
916 
917 err_max_req_slab:
918 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
919 
920 err_dflt_req_slab:
921 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
922 	snic_trc_free();
923 	snic_debugfs_term();
924 #endif
925 	kfree(snic_glob);
926 	snic_glob = NULL;
927 
928 gdi_end:
929 	return ret;
930 } /* end of snic_glob_init */
931 
932 /*
933  * snic_global_data_cleanup : Frees SNIC Global Data
934  */
935 static void
936 snic_global_data_cleanup(void)
937 {
938 	SNIC_BUG_ON(snic_glob == NULL);
939 
940 	destroy_workqueue(snic_glob->event_q);
941 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_TM_CACHE]);
942 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_MAX_SGL]);
943 	kmem_cache_destroy(snic_glob->req_cache[SNIC_REQ_CACHE_DFLT_SGL]);
944 
945 #ifdef CONFIG_SCSI_SNIC_DEBUG_FS
946 	/* Freeing Trace Resources */
947 	snic_trc_free();
948 
949 	/* Freeing Debugfs Resources */
950 	snic_debugfs_term();
951 #endif
952 	kfree(snic_glob);
953 	snic_glob = NULL;
954 } /* end of snic_glob_cleanup */
955 
956 static struct pci_driver snic_driver = {
957 	.name = SNIC_DRV_NAME,
958 	.id_table = snic_id_table,
959 	.probe = snic_probe,
960 	.remove = snic_remove,
961 };
962 
963 static int __init
964 snic_init_module(void)
965 {
966 	int ret = 0;
967 
968 #ifndef __x86_64__
969 	SNIC_INFO("SNIC Driver is supported only for x86_64 platforms!\n");
970 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
971 #endif
972 
973 	SNIC_INFO("%s, ver %s\n", SNIC_DRV_DESCRIPTION, SNIC_DRV_VERSION);
974 
975 	ret = snic_global_data_init();
976 	if (ret) {
977 		SNIC_ERR("Failed to Initialize Global Data.\n");
978 
979 		return ret;
980 	}
981 
982 	ret = pci_register_driver(&snic_driver);
983 	if (ret < 0) {
984 		SNIC_ERR("PCI driver register error\n");
985 
986 		goto err_pci_reg;
987 	}
988 
989 	return ret;
990 
991 err_pci_reg:
992 	snic_global_data_cleanup();
993 
994 	return ret;
995 }
996 
997 static void __exit
998 snic_cleanup_module(void)
999 {
1000 	pci_unregister_driver(&snic_driver);
1001 	snic_global_data_cleanup();
1002 }
1003 
1004 module_init(snic_init_module);
1005 module_exit(snic_cleanup_module);
1006 
1007 MODULE_LICENSE("GPL v2");
1008 MODULE_DESCRIPTION(SNIC_DRV_DESCRIPTION);
1009 MODULE_VERSION(SNIC_DRV_VERSION);
1010 MODULE_DEVICE_TABLE(pci, snic_id_table);
1011 MODULE_AUTHOR("Narsimhulu Musini <nmusini@cisco.com>, "
1012 	      "Sesidhar Baddela <sebaddel@cisco.com>");
1013