ism_drv.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * ISM driver for s390.
  4 *
  5 * Copyright IBM Corp. 2018
  6 */
  7#define pr_fmt(fmt) "ism: " fmt
  8
  9#include <linux/export.h>
 10#include <linux/module.h>
 11#include <linux/types.h>
 12#include <linux/interrupt.h>
 13#include <linux/device.h>
 14#include <linux/err.h>
 15#include <linux/ctype.h>
 16#include <linux/processor.h>
 17
 18#include "ism.h"
 19
 20MODULE_DESCRIPTION("ISM driver for s390");
 21MODULE_LICENSE("GPL");
 22
 23#define DRV_NAME "ism"
 24
 25static const struct pci_device_id ism_device_table[] = {
 26	{ PCI_VDEVICE(IBM, PCI_DEVICE_ID_IBM_ISM), 0 },
 27	{ 0, }
 28};
 29MODULE_DEVICE_TABLE(pci, ism_device_table);
 30
 31static debug_info_t *ism_debug_info;
 32
 33static int ism_cmd(struct ism_dev *ism, void *cmd)
 34{
 35	struct ism_req_hdr *req = cmd;
 36	struct ism_resp_hdr *resp = cmd;
 37
 38	spin_lock(&ism->cmd_lock);
 39	__ism_write_cmd(ism, req + 1, sizeof(*req), req->len - sizeof(*req));
 40	__ism_write_cmd(ism, req, 0, sizeof(*req));
 41
 42	WRITE_ONCE(resp->ret, ISM_ERROR);
 43
 44	__ism_read_cmd(ism, resp, 0, sizeof(*resp));
 45	if (resp->ret) {
 46		debug_text_event(ism_debug_info, 0, "cmd failure");
 47		debug_event(ism_debug_info, 0, resp, sizeof(*resp));
 48		goto out;
 49	}
 50	__ism_read_cmd(ism, resp + 1, sizeof(*resp), resp->len - sizeof(*resp));
 51out:
 52	spin_unlock(&ism->cmd_lock);
 53	return resp->ret;
 54}
 55
 56static int ism_cmd_simple(struct ism_dev *ism, u32 cmd_code)
 57{
 58	union ism_cmd_simple cmd;
 59
 60	memset(&cmd, 0, sizeof(cmd));
 61	cmd.request.hdr.cmd = cmd_code;
 62	cmd.request.hdr.len = sizeof(cmd.request);
 63
 64	return ism_cmd(ism, &cmd);
 65}
 66
 67static int query_info(struct ism_dev *ism)
 68{
 69	union ism_qi cmd;
 70
 71	memset(&cmd, 0, sizeof(cmd));
 72	cmd.request.hdr.cmd = ISM_QUERY_INFO;
 73	cmd.request.hdr.len = sizeof(cmd.request);
 74
 75	if (ism_cmd(ism, &cmd))
 76		goto out;
 77
 78	debug_text_event(ism_debug_info, 3, "query info");
 79	debug_event(ism_debug_info, 3, &cmd.response, sizeof(cmd.response));
 80out:
 81	return 0;
 82}
 83
 84static int register_sba(struct ism_dev *ism)
 85{
 86	union ism_reg_sba cmd;
 87	dma_addr_t dma_handle;
 88	struct ism_sba *sba;
 89
 90	sba = dma_alloc_coherent(&ism->pdev->dev, PAGE_SIZE, &dma_handle,
 91				 GFP_KERNEL);
 92	if (!sba)
 93		return -ENOMEM;
 94
 95	memset(&cmd, 0, sizeof(cmd));
 96	cmd.request.hdr.cmd = ISM_REG_SBA;
 97	cmd.request.hdr.len = sizeof(cmd.request);
 98	cmd.request.sba = dma_handle;
 99
100	if (ism_cmd(ism, &cmd)) {
101		dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, sba, dma_handle);
102		return -EIO;
103	}
104
105	ism->sba = sba;
106	ism->sba_dma_addr = dma_handle;
107
108	return 0;
109}
110
111static int register_ieq(struct ism_dev *ism)
112{
113	union ism_reg_ieq cmd;
114	dma_addr_t dma_handle;
115	struct ism_eq *ieq;
116
117	ieq = dma_alloc_coherent(&ism->pdev->dev, PAGE_SIZE, &dma_handle,
118				 GFP_KERNEL);
119	if (!ieq)
120		return -ENOMEM;
121
122	memset(&cmd, 0, sizeof(cmd));
123	cmd.request.hdr.cmd = ISM_REG_IEQ;
124	cmd.request.hdr.len = sizeof(cmd.request);
125	cmd.request.ieq = dma_handle;
126	cmd.request.len = sizeof(*ieq);
127
128	if (ism_cmd(ism, &cmd)) {
129		dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, ieq, dma_handle);
130		return -EIO;
131	}
132
133	ism->ieq = ieq;
134	ism->ieq_idx = -1;
135	ism->ieq_dma_addr = dma_handle;
136
137	return 0;
138}
139
140static int unregister_sba(struct ism_dev *ism)
141{
142	int ret;
143
144	if (!ism->sba)
145		return 0;
146
147	ret = ism_cmd_simple(ism, ISM_UNREG_SBA);
148	if (ret && ret != ISM_ERROR)
149		return -EIO;
150
151	dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
152			  ism->sba, ism->sba_dma_addr);
153
154	ism->sba = NULL;
155	ism->sba_dma_addr = 0;
156
157	return 0;
158}
159
160static int unregister_ieq(struct ism_dev *ism)
161{
162	int ret;
163
164	if (!ism->ieq)
165		return 0;
166
167	ret = ism_cmd_simple(ism, ISM_UNREG_IEQ);
168	if (ret && ret != ISM_ERROR)
169		return -EIO;
170
171	dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
172			  ism->ieq, ism->ieq_dma_addr);
173
174	ism->ieq = NULL;
175	ism->ieq_dma_addr = 0;
176
177	return 0;
178}
179
180static int ism_read_local_gid(struct dibs_dev *dibs)
181{
182	struct ism_dev *ism = dibs->drv_priv;
183	union ism_read_gid cmd;
184	int ret;
185
186	memset(&cmd, 0, sizeof(cmd));
187	cmd.request.hdr.cmd = ISM_READ_GID;
188	cmd.request.hdr.len = sizeof(cmd.request);
189
190	ret = ism_cmd(ism, &cmd);
191	if (ret)
192		goto out;
193
194	memset(&dibs->gid, 0, sizeof(dibs->gid));
195	memcpy(&dibs->gid, &cmd.response.gid, sizeof(cmd.response.gid));
196out:
197	return ret;
198}
199
200static int ism_query_rgid(struct dibs_dev *dibs, const uuid_t *rgid,
201			  u32 vid_valid, u32 vid)
202{
203	struct ism_dev *ism = dibs->drv_priv;
204	union ism_query_rgid cmd;
205
206	memset(&cmd, 0, sizeof(cmd));
207	cmd.request.hdr.cmd = ISM_QUERY_RGID;
208	cmd.request.hdr.len = sizeof(cmd.request);
209
210	memcpy(&cmd.request.rgid, rgid, sizeof(cmd.request.rgid));
211	cmd.request.vlan_valid = vid_valid;
212	cmd.request.vlan_id = vid;
213
214	return ism_cmd(ism, &cmd);
215}
216
217static int ism_max_dmbs(void)
218{
219	return ISM_NR_DMBS;
220}
221
222static void ism_free_dmb(struct ism_dev *ism, struct dibs_dmb *dmb)
223{
224	clear_bit(dmb->idx, ism->sba_bitmap);
225	dma_unmap_page(&ism->pdev->dev, dmb->dma_addr, dmb->dmb_len,
226		       DMA_FROM_DEVICE);
227	folio_put(virt_to_folio(dmb->cpu_addr));
228}
229
230static int ism_alloc_dmb(struct ism_dev *ism, struct dibs_dmb *dmb)
231{
232	struct folio *folio;
233	unsigned long bit;
234	int rc;
235
236	if (PAGE_ALIGN(dmb->dmb_len) > dma_get_max_seg_size(&ism->pdev->dev))
237		return -EINVAL;
238
239	if (!dmb->idx) {
240		bit = find_next_zero_bit(ism->sba_bitmap, ISM_NR_DMBS,
241					 ISM_DMB_BIT_OFFSET);
242		if (bit == ISM_NR_DMBS)
243			return -ENOSPC;
244
245		dmb->idx = bit;
246	}
247	if (dmb->idx < ISM_DMB_BIT_OFFSET ||
248	    test_and_set_bit(dmb->idx, ism->sba_bitmap))
249		return -EINVAL;
250
251	folio = folio_alloc(GFP_KERNEL | __GFP_NOWARN | __GFP_NOMEMALLOC |
252			    __GFP_NORETRY, get_order(dmb->dmb_len));
253
254	if (!folio) {
255		rc = -ENOMEM;
256		goto out_bit;
257	}
258
259	dmb->cpu_addr = folio_address(folio);
260	dmb->dma_addr = dma_map_page(&ism->pdev->dev,
261				     virt_to_page(dmb->cpu_addr), 0,
262				     dmb->dmb_len, DMA_FROM_DEVICE);
263	if (dma_mapping_error(&ism->pdev->dev, dmb->dma_addr)) {
264		rc = -ENOMEM;
265		goto out_free;
266	}
267
268	return 0;
269
270out_free:
271	kfree(dmb->cpu_addr);
272out_bit:
273	clear_bit(dmb->idx, ism->sba_bitmap);
274	return rc;
275}
276
277static int ism_register_dmb(struct dibs_dev *dibs, struct dibs_dmb *dmb,
278			    struct dibs_client *client)
279{
280	struct ism_dev *ism = dibs->drv_priv;
281	union ism_reg_dmb cmd;
282	unsigned long flags;
283	int ret;
284
285	ret = ism_alloc_dmb(ism, dmb);
286	if (ret)
287		goto out;
288
289	memset(&cmd, 0, sizeof(cmd));
290	cmd.request.hdr.cmd = ISM_REG_DMB;
291	cmd.request.hdr.len = sizeof(cmd.request);
292
293	cmd.request.dmb = dmb->dma_addr;
294	cmd.request.dmb_len = dmb->dmb_len;
295	cmd.request.sba_idx = dmb->idx;
296	cmd.request.vlan_valid = dmb->vlan_valid;
297	cmd.request.vlan_id = dmb->vlan_id;
298	memcpy(&cmd.request.rgid, &dmb->rgid, sizeof(u64));
299
300	ret = ism_cmd(ism, &cmd);
301	if (ret) {
302		ism_free_dmb(ism, dmb);
303		goto out;
304	}
305	dmb->dmb_tok = cmd.response.dmb_tok;
306	spin_lock_irqsave(&dibs->lock, flags);
307	dibs->dmb_clientid_arr[dmb->idx - ISM_DMB_BIT_OFFSET] = client->id;
308	spin_unlock_irqrestore(&dibs->lock, flags);
309out:
310	return ret;
311}
312
313static int ism_unregister_dmb(struct dibs_dev *dibs, struct dibs_dmb *dmb)
314{
315	struct ism_dev *ism = dibs->drv_priv;
316	union ism_unreg_dmb cmd;
317	unsigned long flags;
318	int ret;
319
320	memset(&cmd, 0, sizeof(cmd));
321	cmd.request.hdr.cmd = ISM_UNREG_DMB;
322	cmd.request.hdr.len = sizeof(cmd.request);
323
324	cmd.request.dmb_tok = dmb->dmb_tok;
325
326	spin_lock_irqsave(&dibs->lock, flags);
327	dibs->dmb_clientid_arr[dmb->idx - ISM_DMB_BIT_OFFSET] = NO_DIBS_CLIENT;
328	spin_unlock_irqrestore(&dibs->lock, flags);
329
330	ret = ism_cmd(ism, &cmd);
331	if (ret && ret != ISM_ERROR)
332		goto out;
333
334	ism_free_dmb(ism, dmb);
335out:
336	return ret;
337}
338
339static int ism_add_vlan_id(struct dibs_dev *dibs, u64 vlan_id)
340{
341	struct ism_dev *ism = dibs->drv_priv;
342	union ism_set_vlan_id cmd;
343
344	memset(&cmd, 0, sizeof(cmd));
345	cmd.request.hdr.cmd = ISM_ADD_VLAN_ID;
346	cmd.request.hdr.len = sizeof(cmd.request);
347
348	cmd.request.vlan_id = vlan_id;
349
350	return ism_cmd(ism, &cmd);
351}
352
353static int ism_del_vlan_id(struct dibs_dev *dibs, u64 vlan_id)
354{
355	struct ism_dev *ism = dibs->drv_priv;
356	union ism_set_vlan_id cmd;
357
358	memset(&cmd, 0, sizeof(cmd));
359	cmd.request.hdr.cmd = ISM_DEL_VLAN_ID;
360	cmd.request.hdr.len = sizeof(cmd.request);
361
362	cmd.request.vlan_id = vlan_id;
363
364	return ism_cmd(ism, &cmd);
365}
366
367static int ism_signal_ieq(struct dibs_dev *dibs, const uuid_t *rgid,
368			  u32 trigger_irq, u32 event_code, u64 info)
369{
370	struct ism_dev *ism = dibs->drv_priv;
371	union ism_sig_ieq cmd;
372
373	memset(&cmd, 0, sizeof(cmd));
374	cmd.request.hdr.cmd = ISM_SIGNAL_IEQ;
375	cmd.request.hdr.len = sizeof(cmd.request);
376
377	memcpy(&cmd.request.rgid, rgid, sizeof(cmd.request.rgid));
378	cmd.request.trigger_irq = trigger_irq;
379	cmd.request.event_code = event_code;
380	cmd.request.info = info;
381
382	return ism_cmd(ism, &cmd);
383}
384
385static unsigned int max_bytes(unsigned int start, unsigned int len,
386			      unsigned int boundary)
387{
388	return min(boundary - (start & (boundary - 1)), len);
389}
390
391static int ism_move(struct dibs_dev *dibs, u64 dmb_tok, unsigned int idx,
392		    bool sf, unsigned int offset, void *data,
393		    unsigned int size)
394{
395	struct ism_dev *ism = dibs->drv_priv;
396	unsigned int bytes;
397	u64 dmb_req;
398	int ret;
399
400	while (size) {
401		bytes = max_bytes(offset, size, PAGE_SIZE);
402		dmb_req = ISM_CREATE_REQ(dmb_tok, idx, size == bytes ? sf : 0,
403					 offset);
404
405		ret = __ism_move(ism, dmb_req, data, bytes);
406		if (ret)
407			return ret;
408
409		size -= bytes;
410		data += bytes;
411		offset += bytes;
412	}
413
414	return 0;
415}
416
417static u16 ism_get_chid(struct dibs_dev *dibs)
418{
419	struct ism_dev *ism = dibs->drv_priv;
420
421	if (!ism || !ism->pdev)
422		return 0;
423
424	return to_zpci(ism->pdev)->pchid;
425}
426
427static int ism_match_event_type(u32 s390_event_type)
428{
429	switch (s390_event_type) {
430	case ISM_EVENT_BUF:
431		return DIBS_BUF_EVENT;
432	case ISM_EVENT_DEV:
433		return DIBS_DEV_EVENT;
434	case ISM_EVENT_SWR:
435		return DIBS_SW_EVENT;
436	default:
437		return DIBS_OTHER_TYPE;
438	}
439}
440
441static int ism_match_event_subtype(u32 s390_event_subtype)
442{
443	switch (s390_event_subtype) {
444	case ISM_BUF_DMB_UNREGISTERED:
445		return DIBS_BUF_UNREGISTERED;
446	case ISM_DEV_GID_DISABLED:
447		return DIBS_DEV_DISABLED;
448	case ISM_DEV_GID_ERR_STATE:
449		return DIBS_DEV_ERR_STATE;
450	default:
451		return DIBS_OTHER_SUBTYPE;
452	}
453}
454
455static void ism_handle_event(struct ism_dev *ism)
456{
457	struct dibs_dev *dibs = ism->dibs;
458	struct dibs_event event;
459	struct ism_event *entry;
460	struct dibs_client *clt;
461	int i;
462
463	while ((ism->ieq_idx + 1) != READ_ONCE(ism->ieq->header.idx)) {
464		if (++ism->ieq_idx == ARRAY_SIZE(ism->ieq->entry))
465			ism->ieq_idx = 0;
466
467		entry = &ism->ieq->entry[ism->ieq_idx];
468		debug_event(ism_debug_info, 2, entry, sizeof(*entry));
469		__memset(&event, 0, sizeof(event));
470		event.type = ism_match_event_type(entry->type);
471		if (event.type == DIBS_SW_EVENT)
472			event.subtype = entry->code;
473		else
474			event.subtype = ism_match_event_subtype(entry->code);
475		event.time = entry->time;
476		event.data = entry->info;
477		switch (event.type) {
478		case DIBS_BUF_EVENT:
479			event.buffer_tok = entry->tok;
480			break;
481		case DIBS_DEV_EVENT:
482		case DIBS_SW_EVENT:
483			memcpy(&event.gid, &entry->tok, sizeof(u64));
484		}
485		for (i = 0; i < MAX_DIBS_CLIENTS; ++i) {
486			clt = dibs->subs[i];
487			if (clt)
488				clt->ops->handle_event(dibs, &event);
489		}
490	}
491}
492
493static irqreturn_t ism_handle_irq(int irq, void *data)
494{
495	struct ism_dev *ism = data;
496	unsigned long bit, end;
497	struct dibs_dev *dibs;
498	unsigned long *bv;
499	u16 dmbemask;
500	u8 client_id;
501
502	dibs = ism->dibs;
503
504	bv = (void *) &ism->sba->dmb_bits[ISM_DMB_WORD_OFFSET];
505	end = sizeof(ism->sba->dmb_bits) * BITS_PER_BYTE - ISM_DMB_BIT_OFFSET;
506
507	spin_lock(&dibs->lock);
508	ism->sba->s = 0;
509	barrier();
510	for (bit = 0;;) {
511		bit = find_next_bit_inv(bv, end, bit);
512		if (bit >= end)
513			break;
514
515		clear_bit_inv(bit, bv);
516		dmbemask = ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET];
517		ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0;
518		barrier();
519		client_id = dibs->dmb_clientid_arr[bit];
520		if (unlikely(client_id == NO_DIBS_CLIENT ||
521			     !dibs->subs[client_id]))
522			continue;
523		dibs->subs[client_id]->ops->handle_irq(dibs,
524						       bit + ISM_DMB_BIT_OFFSET,
525						       dmbemask);
526	}
527
528	if (ism->sba->e) {
529		ism->sba->e = 0;
530		barrier();
531		ism_handle_event(ism);
532	}
533	spin_unlock(&dibs->lock);
534	return IRQ_HANDLED;
535}
536
537static const struct dibs_dev_ops ism_ops = {
538	.get_fabric_id = ism_get_chid,
539	.query_remote_gid = ism_query_rgid,
540	.max_dmbs = ism_max_dmbs,
541	.register_dmb = ism_register_dmb,
542	.unregister_dmb = ism_unregister_dmb,
543	.move_data = ism_move,
544	.add_vlan_id = ism_add_vlan_id,
545	.del_vlan_id = ism_del_vlan_id,
546	.signal_event = ism_signal_ieq,
547};
548
549static int ism_dev_init(struct ism_dev *ism)
550{
551	struct pci_dev *pdev = ism->pdev;
552	int ret;
553
554	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
555	if (ret <= 0)
556		goto out;
557
558	ret = request_irq(pci_irq_vector(pdev, 0), ism_handle_irq, 0,
559			  pci_name(pdev), ism);
560	if (ret)
561		goto free_vectors;
562
563	ret = register_sba(ism);
564	if (ret)
565		goto free_irq;
566
567	ret = register_ieq(ism);
568	if (ret)
569		goto unreg_sba;
570
571	query_info(ism);
572	return 0;
573
574unreg_sba:
575	unregister_sba(ism);
576free_irq:
577	free_irq(pci_irq_vector(pdev, 0), ism);
578free_vectors:
579	pci_free_irq_vectors(pdev);
580out:
581	return ret;
582}
583
584static void ism_dev_exit(struct ism_dev *ism)
585{
586	struct pci_dev *pdev = ism->pdev;
587
588	unregister_ieq(ism);
589	unregister_sba(ism);
590	free_irq(pci_irq_vector(pdev, 0), ism);
591	pci_free_irq_vectors(pdev);
592}
593
594static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
595{
596	struct dibs_dev *dibs;
597	struct zpci_dev *zdev;
598	struct ism_dev *ism;
599	int ret;
600
601	ism = kzalloc(sizeof(*ism), GFP_KERNEL);
602	if (!ism)
603		return -ENOMEM;
604
605	spin_lock_init(&ism->cmd_lock);
606	dev_set_drvdata(&pdev->dev, ism);
607	ism->pdev = pdev;
608
609	ret = pci_enable_device_mem(pdev);
610	if (ret)
611		goto err_dev;
612
613	ret = pci_request_mem_regions(pdev, DRV_NAME);
614	if (ret)
615		goto err_disable;
616
617	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
618	if (ret)
619		goto err_resource;
620
621	dma_set_seg_boundary(&pdev->dev, SZ_1M - 1);
622	dma_set_max_seg_size(&pdev->dev, SZ_1M);
623	pci_set_master(pdev);
624
625	dibs = dibs_dev_alloc();
626	if (!dibs) {
627		ret = -ENOMEM;
628		goto err_resource;
629	}
630	/* set this up before we enable interrupts */
631	ism->dibs = dibs;
632	dibs->drv_priv = ism;
633	dibs->ops = &ism_ops;
634
635	/* enable ism device, but any interrupts and events will be ignored
636	 * before dibs_dev_add() adds it to any clients.
637	 */
638	ret = ism_dev_init(ism);
639	if (ret)
640		goto err_dibs;
641
642	/* after ism_dev_init() we can call ism function to set gid */
643	ret = ism_read_local_gid(dibs);
644	if (ret)
645		goto err_ism;
646
647	dibs->dev.parent = &pdev->dev;
648
649	zdev = to_zpci(pdev);
650	dev_set_name(&dibs->dev, "ism%x", zdev->uid ? zdev->uid : zdev->fid);
651
652	ret = dibs_dev_add(dibs);
653	if (ret)
654		goto err_ism;
655
656	return 0;
657
658err_ism:
659	ism_dev_exit(ism);
660err_dibs:
661	/* pairs with dibs_dev_alloc() */
662	put_device(&dibs->dev);
663err_resource:
664	pci_release_mem_regions(pdev);
665err_disable:
666	pci_disable_device(pdev);
667err_dev:
668	dev_set_drvdata(&pdev->dev, NULL);
669	kfree(ism);
670
671	return ret;
672}
673
674static void ism_remove(struct pci_dev *pdev)
675{
676	struct ism_dev *ism = dev_get_drvdata(&pdev->dev);
677	struct dibs_dev *dibs = ism->dibs;
678
679	dibs_dev_del(dibs);
680	ism_dev_exit(ism);
681	/* pairs with dibs_dev_alloc() */
682	put_device(&dibs->dev);
683
684	pci_release_mem_regions(pdev);
685	pci_disable_device(pdev);
686	dev_set_drvdata(&pdev->dev, NULL);
687	kfree(ism);
688}
689
690static struct pci_driver ism_driver = {
691	.name	  = DRV_NAME,
692	.id_table = ism_device_table,
693	.probe	  = ism_probe,
694	.remove	  = ism_remove,
695};
696
697static int __init ism_init(void)
698{
699	int ret;
700
701	ism_debug_info = debug_register("ism", 2, 1, 16);
702	if (!ism_debug_info)
703		return -ENODEV;
704
705	debug_register_view(ism_debug_info, &debug_hex_ascii_view);
706	ret = pci_register_driver(&ism_driver);
707	if (ret)
708		debug_unregister(ism_debug_info);
709
710	return ret;
711}
712
713static void __exit ism_exit(void)
714{
715	pci_unregister_driver(&ism_driver);
716	debug_unregister(ism_debug_info);
717}
718
719module_init(ism_init);
720module_exit(ism_exit);