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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2014 Intel Corp.
4 * Author: Jiang Liu <jiang.liu@linux.intel.com>
5 *
6 * This file is licensed under GPLv2.
7 *
8 * This file contains common code to support Message Signaled Interrupts for
9 * PCI compatible and non PCI compatible devices.
10 */
11#include <linux/types.h>
12#include <linux/device.h>
13#include <linux/irq.h>
14#include <linux/irqdomain.h>
15#include <linux/msi.h>
16#include <linux/slab.h>
17#include <linux/sysfs.h>
18#include <linux/pci.h>
19
20#include "internals.h"
21
22/**
23 * struct msi_ctrl - MSI internal management control structure
24 * @domid: ID of the domain on which management operations should be done
25 * @first: First (hardware) slot index to operate on
26 * @last: Last (hardware) slot index to operate on
27 * @nirqs: The number of Linux interrupts to allocate. Can be larger
28 * than the range due to PCI/multi-MSI.
29 */
30struct msi_ctrl {
31 unsigned int domid;
32 unsigned int first;
33 unsigned int last;
34 unsigned int nirqs;
35};
36
37/* Invalid Xarray index which is outside of any searchable range */
38#define MSI_XA_MAX_INDEX (ULONG_MAX - 1)
39/* The maximum domain size */
40#define MSI_XA_DOMAIN_SIZE (MSI_MAX_INDEX + 1)
41
42static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl);
43static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid);
44static inline int msi_sysfs_create_group(struct device *dev);
45
46
47/**
48 * msi_alloc_desc - Allocate an initialized msi_desc
49 * @dev: Pointer to the device for which this is allocated
50 * @nvec: The number of vectors used in this entry
51 * @affinity: Optional pointer to an affinity mask array size of @nvec
52 *
53 * If @affinity is not %NULL then an affinity array[@nvec] is allocated
54 * and the affinity masks and flags from @affinity are copied.
55 *
56 * Return: pointer to allocated &msi_desc on success or %NULL on failure
57 */
58static struct msi_desc *msi_alloc_desc(struct device *dev, int nvec,
59 const struct irq_affinity_desc *affinity)
60{
61 struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
62
63 if (!desc)
64 return NULL;
65
66 desc->dev = dev;
67 desc->nvec_used = nvec;
68 if (affinity) {
69 desc->affinity = kmemdup(affinity, nvec * sizeof(*desc->affinity), GFP_KERNEL);
70 if (!desc->affinity) {
71 kfree(desc);
72 return NULL;
73 }
74 }
75 return desc;
76}
77
78static void msi_free_desc(struct msi_desc *desc)
79{
80 kfree(desc->affinity);
81 kfree(desc);
82}
83
84static int msi_insert_desc(struct device *dev, struct msi_desc *desc,
85 unsigned int domid, unsigned int index)
86{
87 struct msi_device_data *md = dev->msi.data;
88 struct xarray *xa = &md->__domains[domid].store;
89 unsigned int hwsize;
90 int ret;
91
92 hwsize = msi_domain_get_hwsize(dev, domid);
93
94 if (index == MSI_ANY_INDEX) {
95 struct xa_limit limit = { .min = 0, .max = hwsize - 1 };
96 unsigned int index;
97
98 /* Let the xarray allocate a free index within the limit */
99 ret = xa_alloc(xa, &index, desc, limit, GFP_KERNEL);
100 if (ret)
101 goto fail;
102
103 desc->msi_index = index;
104 return 0;
105 } else {
106 if (index >= hwsize) {
107 ret = -ERANGE;
108 goto fail;
109 }
110
111 desc->msi_index = index;
112 ret = xa_insert(xa, index, desc, GFP_KERNEL);
113 if (ret)
114 goto fail;
115 return 0;
116 }
117fail:
118 msi_free_desc(desc);
119 return ret;
120}
121
122/**
123 * msi_domain_insert_msi_desc - Allocate and initialize a MSI descriptor and
124 * insert it at @init_desc->msi_index
125 *
126 * @dev: Pointer to the device for which the descriptor is allocated
127 * @domid: The id of the interrupt domain to which the desriptor is added
128 * @init_desc: Pointer to an MSI descriptor to initialize the new descriptor
129 *
130 * Return: 0 on success or an appropriate failure code.
131 */
132int msi_domain_insert_msi_desc(struct device *dev, unsigned int domid,
133 struct msi_desc *init_desc)
134{
135 struct msi_desc *desc;
136
137 lockdep_assert_held(&dev->msi.data->mutex);
138
139 desc = msi_alloc_desc(dev, init_desc->nvec_used, init_desc->affinity);
140 if (!desc)
141 return -ENOMEM;
142
143 /* Copy type specific data to the new descriptor. */
144 desc->pci = init_desc->pci;
145
146 return msi_insert_desc(dev, desc, domid, init_desc->msi_index);
147}
148
149static bool msi_desc_match(struct msi_desc *desc, enum msi_desc_filter filter)
150{
151 switch (filter) {
152 case MSI_DESC_ALL:
153 return true;
154 case MSI_DESC_NOTASSOCIATED:
155 return !desc->irq;
156 case MSI_DESC_ASSOCIATED:
157 return !!desc->irq;
158 }
159 WARN_ON_ONCE(1);
160 return false;
161}
162
163static bool msi_ctrl_valid(struct device *dev, struct msi_ctrl *ctrl)
164{
165 unsigned int hwsize;
166
167 if (WARN_ON_ONCE(ctrl->domid >= MSI_MAX_DEVICE_IRQDOMAINS ||
168 (dev->msi.domain &&
169 !dev->msi.data->__domains[ctrl->domid].domain)))
170 return false;
171
172 hwsize = msi_domain_get_hwsize(dev, ctrl->domid);
173 if (WARN_ON_ONCE(ctrl->first > ctrl->last ||
174 ctrl->first >= hwsize ||
175 ctrl->last >= hwsize))
176 return false;
177 return true;
178}
179
180static void msi_domain_free_descs(struct device *dev, struct msi_ctrl *ctrl)
181{
182 struct msi_desc *desc;
183 struct xarray *xa;
184 unsigned long idx;
185
186 lockdep_assert_held(&dev->msi.data->mutex);
187
188 if (!msi_ctrl_valid(dev, ctrl))
189 return;
190
191 xa = &dev->msi.data->__domains[ctrl->domid].store;
192 xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
193 xa_erase(xa, idx);
194
195 /* Leak the descriptor when it is still referenced */
196 if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED)))
197 continue;
198 msi_free_desc(desc);
199 }
200}
201
202/**
203 * msi_domain_free_msi_descs_range - Free a range of MSI descriptors of a device in an irqdomain
204 * @dev: Device for which to free the descriptors
205 * @domid: Id of the domain to operate on
206 * @first: Index to start freeing from (inclusive)
207 * @last: Last index to be freed (inclusive)
208 */
209void msi_domain_free_msi_descs_range(struct device *dev, unsigned int domid,
210 unsigned int first, unsigned int last)
211{
212 struct msi_ctrl ctrl = {
213 .domid = domid,
214 .first = first,
215 .last = last,
216 };
217
218 msi_domain_free_descs(dev, &ctrl);
219}
220
221/**
222 * msi_domain_add_simple_msi_descs - Allocate and initialize MSI descriptors
223 * @dev: Pointer to the device for which the descriptors are allocated
224 * @ctrl: Allocation control struct
225 *
226 * Return: 0 on success or an appropriate failure code.
227 */
228static int msi_domain_add_simple_msi_descs(struct device *dev, struct msi_ctrl *ctrl)
229{
230 struct msi_desc *desc;
231 unsigned int idx;
232 int ret;
233
234 lockdep_assert_held(&dev->msi.data->mutex);
235
236 if (!msi_ctrl_valid(dev, ctrl))
237 return -EINVAL;
238
239 for (idx = ctrl->first; idx <= ctrl->last; idx++) {
240 desc = msi_alloc_desc(dev, 1, NULL);
241 if (!desc)
242 goto fail_mem;
243 ret = msi_insert_desc(dev, desc, ctrl->domid, idx);
244 if (ret)
245 goto fail;
246 }
247 return 0;
248
249fail_mem:
250 ret = -ENOMEM;
251fail:
252 msi_domain_free_descs(dev, ctrl);
253 return ret;
254}
255
256void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
257{
258 *msg = entry->msg;
259}
260
261void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
262{
263 struct msi_desc *entry = irq_get_msi_desc(irq);
264
265 __get_cached_msi_msg(entry, msg);
266}
267EXPORT_SYMBOL_GPL(get_cached_msi_msg);
268
269static void msi_device_data_release(struct device *dev, void *res)
270{
271 struct msi_device_data *md = res;
272 int i;
273
274 for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++) {
275 msi_remove_device_irq_domain(dev, i);
276 WARN_ON_ONCE(!xa_empty(&md->__domains[i].store));
277 xa_destroy(&md->__domains[i].store);
278 }
279 dev->msi.data = NULL;
280}
281
282/**
283 * msi_setup_device_data - Setup MSI device data
284 * @dev: Device for which MSI device data should be set up
285 *
286 * Return: 0 on success, appropriate error code otherwise
287 *
288 * This can be called more than once for @dev. If the MSI device data is
289 * already allocated the call succeeds. The allocated memory is
290 * automatically released when the device is destroyed.
291 */
292int msi_setup_device_data(struct device *dev)
293{
294 struct msi_device_data *md;
295 int ret, i;
296
297 if (dev->msi.data)
298 return 0;
299
300 md = devres_alloc(msi_device_data_release, sizeof(*md), GFP_KERNEL);
301 if (!md)
302 return -ENOMEM;
303
304 ret = msi_sysfs_create_group(dev);
305 if (ret) {
306 devres_free(md);
307 return ret;
308 }
309
310 for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++)
311 xa_init_flags(&md->__domains[i].store, XA_FLAGS_ALLOC);
312
313 /*
314 * If @dev::msi::domain is set and is a global MSI domain, copy the
315 * pointer into the domain array so all code can operate on domain
316 * ids. The NULL pointer check is required to keep the legacy
317 * architecture specific PCI/MSI support working.
318 */
319 if (dev->msi.domain && !irq_domain_is_msi_parent(dev->msi.domain))
320 md->__domains[MSI_DEFAULT_DOMAIN].domain = dev->msi.domain;
321
322 mutex_init(&md->mutex);
323 dev->msi.data = md;
324 devres_add(dev, md);
325 return 0;
326}
327
328/**
329 * msi_lock_descs - Lock the MSI descriptor storage of a device
330 * @dev: Device to operate on
331 */
332void msi_lock_descs(struct device *dev)
333{
334 mutex_lock(&dev->msi.data->mutex);
335}
336EXPORT_SYMBOL_GPL(msi_lock_descs);
337
338/**
339 * msi_unlock_descs - Unlock the MSI descriptor storage of a device
340 * @dev: Device to operate on
341 */
342void msi_unlock_descs(struct device *dev)
343{
344 /* Invalidate the index which was cached by the iterator */
345 dev->msi.data->__iter_idx = MSI_XA_MAX_INDEX;
346 mutex_unlock(&dev->msi.data->mutex);
347}
348EXPORT_SYMBOL_GPL(msi_unlock_descs);
349
350static struct msi_desc *msi_find_desc(struct msi_device_data *md, unsigned int domid,
351 enum msi_desc_filter filter)
352{
353 struct xarray *xa = &md->__domains[domid].store;
354 struct msi_desc *desc;
355
356 xa_for_each_start(xa, md->__iter_idx, desc, md->__iter_idx) {
357 if (msi_desc_match(desc, filter))
358 return desc;
359 }
360 md->__iter_idx = MSI_XA_MAX_INDEX;
361 return NULL;
362}
363
364/**
365 * msi_domain_first_desc - Get the first MSI descriptor of an irqdomain associated to a device
366 * @dev: Device to operate on
367 * @domid: The id of the interrupt domain which should be walked.
368 * @filter: Descriptor state filter
369 *
370 * Must be called with the MSI descriptor mutex held, i.e. msi_lock_descs()
371 * must be invoked before the call.
372 *
373 * Return: Pointer to the first MSI descriptor matching the search
374 * criteria, NULL if none found.
375 */
376struct msi_desc *msi_domain_first_desc(struct device *dev, unsigned int domid,
377 enum msi_desc_filter filter)
378{
379 struct msi_device_data *md = dev->msi.data;
380
381 if (WARN_ON_ONCE(!md || domid >= MSI_MAX_DEVICE_IRQDOMAINS))
382 return NULL;
383
384 lockdep_assert_held(&md->mutex);
385
386 md->__iter_idx = 0;
387 return msi_find_desc(md, domid, filter);
388}
389EXPORT_SYMBOL_GPL(msi_domain_first_desc);
390
391/**
392 * msi_next_desc - Get the next MSI descriptor of a device
393 * @dev: Device to operate on
394 * @domid: The id of the interrupt domain which should be walked.
395 * @filter: Descriptor state filter
396 *
397 * The first invocation of msi_next_desc() has to be preceeded by a
398 * successful invocation of __msi_first_desc(). Consecutive invocations are
399 * only valid if the previous one was successful. All these operations have
400 * to be done within the same MSI mutex held region.
401 *
402 * Return: Pointer to the next MSI descriptor matching the search
403 * criteria, NULL if none found.
404 */
405struct msi_desc *msi_next_desc(struct device *dev, unsigned int domid,
406 enum msi_desc_filter filter)
407{
408 struct msi_device_data *md = dev->msi.data;
409
410 if (WARN_ON_ONCE(!md || domid >= MSI_MAX_DEVICE_IRQDOMAINS))
411 return NULL;
412
413 lockdep_assert_held(&md->mutex);
414
415 if (md->__iter_idx >= (unsigned long)MSI_MAX_INDEX)
416 return NULL;
417
418 md->__iter_idx++;
419 return msi_find_desc(md, domid, filter);
420}
421EXPORT_SYMBOL_GPL(msi_next_desc);
422
423/**
424 * msi_domain_get_virq - Lookup the Linux interrupt number for a MSI index on a interrupt domain
425 * @dev: Device to operate on
426 * @domid: Domain ID of the interrupt domain associated to the device
427 * @index: MSI interrupt index to look for (0-based)
428 *
429 * Return: The Linux interrupt number on success (> 0), 0 if not found
430 */
431unsigned int msi_domain_get_virq(struct device *dev, unsigned int domid, unsigned int index)
432{
433 struct msi_desc *desc;
434 unsigned int ret = 0;
435 bool pcimsi = false;
436 struct xarray *xa;
437
438 if (!dev->msi.data)
439 return 0;
440
441 if (WARN_ON_ONCE(index > MSI_MAX_INDEX || domid >= MSI_MAX_DEVICE_IRQDOMAINS))
442 return 0;
443
444 /* This check is only valid for the PCI default MSI domain */
445 if (dev_is_pci(dev) && domid == MSI_DEFAULT_DOMAIN)
446 pcimsi = to_pci_dev(dev)->msi_enabled;
447
448 msi_lock_descs(dev);
449 xa = &dev->msi.data->__domains[domid].store;
450 desc = xa_load(xa, pcimsi ? 0 : index);
451 if (desc && desc->irq) {
452 /*
453 * PCI-MSI has only one descriptor for multiple interrupts.
454 * PCI-MSIX and platform MSI use a descriptor per
455 * interrupt.
456 */
457 if (pcimsi) {
458 if (index < desc->nvec_used)
459 ret = desc->irq + index;
460 } else {
461 ret = desc->irq;
462 }
463 }
464
465 msi_unlock_descs(dev);
466 return ret;
467}
468EXPORT_SYMBOL_GPL(msi_domain_get_virq);
469
470#ifdef CONFIG_SYSFS
471static struct attribute *msi_dev_attrs[] = {
472 NULL
473};
474
475static const struct attribute_group msi_irqs_group = {
476 .name = "msi_irqs",
477 .attrs = msi_dev_attrs,
478};
479
480static inline int msi_sysfs_create_group(struct device *dev)
481{
482 return devm_device_add_group(dev, &msi_irqs_group);
483}
484
485static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
486 char *buf)
487{
488 /* MSI vs. MSIX is per device not per interrupt */
489 bool is_msix = dev_is_pci(dev) ? to_pci_dev(dev)->msix_enabled : false;
490
491 return sysfs_emit(buf, "%s\n", is_msix ? "msix" : "msi");
492}
493
494static void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc)
495{
496 struct device_attribute *attrs = desc->sysfs_attrs;
497 int i;
498
499 if (!attrs)
500 return;
501
502 desc->sysfs_attrs = NULL;
503 for (i = 0; i < desc->nvec_used; i++) {
504 if (attrs[i].show)
505 sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name);
506 kfree(attrs[i].attr.name);
507 }
508 kfree(attrs);
509}
510
511static int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc)
512{
513 struct device_attribute *attrs;
514 int ret, i;
515
516 attrs = kcalloc(desc->nvec_used, sizeof(*attrs), GFP_KERNEL);
517 if (!attrs)
518 return -ENOMEM;
519
520 desc->sysfs_attrs = attrs;
521 for (i = 0; i < desc->nvec_used; i++) {
522 sysfs_attr_init(&attrs[i].attr);
523 attrs[i].attr.name = kasprintf(GFP_KERNEL, "%d", desc->irq + i);
524 if (!attrs[i].attr.name) {
525 ret = -ENOMEM;
526 goto fail;
527 }
528
529 attrs[i].attr.mode = 0444;
530 attrs[i].show = msi_mode_show;
531
532 ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name);
533 if (ret) {
534 attrs[i].show = NULL;
535 goto fail;
536 }
537 }
538 return 0;
539
540fail:
541 msi_sysfs_remove_desc(dev, desc);
542 return ret;
543}
544
545#if defined(CONFIG_PCI_MSI_ARCH_FALLBACKS) || defined(CONFIG_PCI_XEN)
546/**
547 * msi_device_populate_sysfs - Populate msi_irqs sysfs entries for a device
548 * @dev: The device (PCI, platform etc) which will get sysfs entries
549 */
550int msi_device_populate_sysfs(struct device *dev)
551{
552 struct msi_desc *desc;
553 int ret;
554
555 msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) {
556 if (desc->sysfs_attrs)
557 continue;
558 ret = msi_sysfs_populate_desc(dev, desc);
559 if (ret)
560 return ret;
561 }
562 return 0;
563}
564
565/**
566 * msi_device_destroy_sysfs - Destroy msi_irqs sysfs entries for a device
567 * @dev: The device (PCI, platform etc) for which to remove
568 * sysfs entries
569 */
570void msi_device_destroy_sysfs(struct device *dev)
571{
572 struct msi_desc *desc;
573
574 msi_for_each_desc(desc, dev, MSI_DESC_ALL)
575 msi_sysfs_remove_desc(dev, desc);
576}
577#endif /* CONFIG_PCI_MSI_ARCH_FALLBACK || CONFIG_PCI_XEN */
578#else /* CONFIG_SYSFS */
579static inline int msi_sysfs_create_group(struct device *dev) { return 0; }
580static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; }
581static inline void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) { }
582#endif /* !CONFIG_SYSFS */
583
584static struct irq_domain *msi_get_device_domain(struct device *dev, unsigned int domid)
585{
586 struct irq_domain *domain;
587
588 lockdep_assert_held(&dev->msi.data->mutex);
589
590 if (WARN_ON_ONCE(domid >= MSI_MAX_DEVICE_IRQDOMAINS))
591 return NULL;
592
593 domain = dev->msi.data->__domains[domid].domain;
594 if (!domain)
595 return NULL;
596
597 if (WARN_ON_ONCE(irq_domain_is_msi_parent(domain)))
598 return NULL;
599
600 return domain;
601}
602
603static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid)
604{
605 struct msi_domain_info *info;
606 struct irq_domain *domain;
607
608 domain = msi_get_device_domain(dev, domid);
609 if (domain) {
610 info = domain->host_data;
611 return info->hwsize;
612 }
613 /* No domain, default to MSI_XA_DOMAIN_SIZE */
614 return MSI_XA_DOMAIN_SIZE;
615}
616
617static inline void irq_chip_write_msi_msg(struct irq_data *data,
618 struct msi_msg *msg)
619{
620 data->chip->irq_write_msi_msg(data, msg);
621}
622
623static void msi_check_level(struct irq_domain *domain, struct msi_msg *msg)
624{
625 struct msi_domain_info *info = domain->host_data;
626
627 /*
628 * If the MSI provider has messed with the second message and
629 * not advertized that it is level-capable, signal the breakage.
630 */
631 WARN_ON(!((info->flags & MSI_FLAG_LEVEL_CAPABLE) &&
632 (info->chip->flags & IRQCHIP_SUPPORTS_LEVEL_MSI)) &&
633 (msg[1].address_lo || msg[1].address_hi || msg[1].data));
634}
635
636/**
637 * msi_domain_set_affinity - Generic affinity setter function for MSI domains
638 * @irq_data: The irq data associated to the interrupt
639 * @mask: The affinity mask to set
640 * @force: Flag to enforce setting (disable online checks)
641 *
642 * Intended to be used by MSI interrupt controllers which are
643 * implemented with hierarchical domains.
644 *
645 * Return: IRQ_SET_MASK_* result code
646 */
647int msi_domain_set_affinity(struct irq_data *irq_data,
648 const struct cpumask *mask, bool force)
649{
650 struct irq_data *parent = irq_data->parent_data;
651 struct msi_msg msg[2] = { [1] = { }, };
652 int ret;
653
654 ret = parent->chip->irq_set_affinity(parent, mask, force);
655 if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) {
656 BUG_ON(irq_chip_compose_msi_msg(irq_data, msg));
657 msi_check_level(irq_data->domain, msg);
658 irq_chip_write_msi_msg(irq_data, msg);
659 }
660
661 return ret;
662}
663
664static int msi_domain_activate(struct irq_domain *domain,
665 struct irq_data *irq_data, bool early)
666{
667 struct msi_msg msg[2] = { [1] = { }, };
668
669 BUG_ON(irq_chip_compose_msi_msg(irq_data, msg));
670 msi_check_level(irq_data->domain, msg);
671 irq_chip_write_msi_msg(irq_data, msg);
672 return 0;
673}
674
675static void msi_domain_deactivate(struct irq_domain *domain,
676 struct irq_data *irq_data)
677{
678 struct msi_msg msg[2];
679
680 memset(msg, 0, sizeof(msg));
681 irq_chip_write_msi_msg(irq_data, msg);
682}
683
684static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
685 unsigned int nr_irqs, void *arg)
686{
687 struct msi_domain_info *info = domain->host_data;
688 struct msi_domain_ops *ops = info->ops;
689 irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
690 int i, ret;
691
692 if (irq_find_mapping(domain, hwirq) > 0)
693 return -EEXIST;
694
695 if (domain->parent) {
696 ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
697 if (ret < 0)
698 return ret;
699 }
700
701 for (i = 0; i < nr_irqs; i++) {
702 ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg);
703 if (ret < 0) {
704 if (ops->msi_free) {
705 for (i--; i > 0; i--)
706 ops->msi_free(domain, info, virq + i);
707 }
708 irq_domain_free_irqs_top(domain, virq, nr_irqs);
709 return ret;
710 }
711 }
712
713 return 0;
714}
715
716static void msi_domain_free(struct irq_domain *domain, unsigned int virq,
717 unsigned int nr_irqs)
718{
719 struct msi_domain_info *info = domain->host_data;
720 int i;
721
722 if (info->ops->msi_free) {
723 for (i = 0; i < nr_irqs; i++)
724 info->ops->msi_free(domain, info, virq + i);
725 }
726 irq_domain_free_irqs_top(domain, virq, nr_irqs);
727}
728
729static const struct irq_domain_ops msi_domain_ops = {
730 .alloc = msi_domain_alloc,
731 .free = msi_domain_free,
732 .activate = msi_domain_activate,
733 .deactivate = msi_domain_deactivate,
734};
735
736static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info,
737 msi_alloc_info_t *arg)
738{
739 return arg->hwirq;
740}
741
742static int msi_domain_ops_prepare(struct irq_domain *domain, struct device *dev,
743 int nvec, msi_alloc_info_t *arg)
744{
745 memset(arg, 0, sizeof(*arg));
746 return 0;
747}
748
749static void msi_domain_ops_set_desc(msi_alloc_info_t *arg,
750 struct msi_desc *desc)
751{
752 arg->desc = desc;
753}
754
755static int msi_domain_ops_init(struct irq_domain *domain,
756 struct msi_domain_info *info,
757 unsigned int virq, irq_hw_number_t hwirq,
758 msi_alloc_info_t *arg)
759{
760 irq_domain_set_hwirq_and_chip(domain, virq, hwirq, info->chip,
761 info->chip_data);
762 if (info->handler && info->handler_name) {
763 __irq_set_handler(virq, info->handler, 0, info->handler_name);
764 if (info->handler_data)
765 irq_set_handler_data(virq, info->handler_data);
766 }
767 return 0;
768}
769
770static struct msi_domain_ops msi_domain_ops_default = {
771 .get_hwirq = msi_domain_ops_get_hwirq,
772 .msi_init = msi_domain_ops_init,
773 .msi_prepare = msi_domain_ops_prepare,
774 .set_desc = msi_domain_ops_set_desc,
775};
776
777static void msi_domain_update_dom_ops(struct msi_domain_info *info)
778{
779 struct msi_domain_ops *ops = info->ops;
780
781 if (ops == NULL) {
782 info->ops = &msi_domain_ops_default;
783 return;
784 }
785
786 if (!(info->flags & MSI_FLAG_USE_DEF_DOM_OPS))
787 return;
788
789 if (ops->get_hwirq == NULL)
790 ops->get_hwirq = msi_domain_ops_default.get_hwirq;
791 if (ops->msi_init == NULL)
792 ops->msi_init = msi_domain_ops_default.msi_init;
793 if (ops->msi_prepare == NULL)
794 ops->msi_prepare = msi_domain_ops_default.msi_prepare;
795 if (ops->set_desc == NULL)
796 ops->set_desc = msi_domain_ops_default.set_desc;
797}
798
799static void msi_domain_update_chip_ops(struct msi_domain_info *info)
800{
801 struct irq_chip *chip = info->chip;
802
803 BUG_ON(!chip || !chip->irq_mask || !chip->irq_unmask);
804 if (!chip->irq_set_affinity)
805 chip->irq_set_affinity = msi_domain_set_affinity;
806}
807
808static struct irq_domain *__msi_create_irq_domain(struct fwnode_handle *fwnode,
809 struct msi_domain_info *info,
810 unsigned int flags,
811 struct irq_domain *parent)
812{
813 struct irq_domain *domain;
814
815 if (info->hwsize > MSI_XA_DOMAIN_SIZE)
816 return NULL;
817
818 /*
819 * Hardware size 0 is valid for backwards compatibility and for
820 * domains which are not backed by a hardware table. Grant the
821 * maximum index space.
822 */
823 if (!info->hwsize)
824 info->hwsize = MSI_XA_DOMAIN_SIZE;
825
826 msi_domain_update_dom_ops(info);
827 if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
828 msi_domain_update_chip_ops(info);
829
830 domain = irq_domain_create_hierarchy(parent, flags | IRQ_DOMAIN_FLAG_MSI, 0,
831 fwnode, &msi_domain_ops, info);
832
833 if (domain)
834 irq_domain_update_bus_token(domain, info->bus_token);
835
836 return domain;
837}
838
839/**
840 * msi_create_irq_domain - Create an MSI interrupt domain
841 * @fwnode: Optional fwnode of the interrupt controller
842 * @info: MSI domain info
843 * @parent: Parent irq domain
844 *
845 * Return: pointer to the created &struct irq_domain or %NULL on failure
846 */
847struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
848 struct msi_domain_info *info,
849 struct irq_domain *parent)
850{
851 return __msi_create_irq_domain(fwnode, info, 0, parent);
852}
853
854/**
855 * msi_parent_init_dev_msi_info - Delegate initialization of device MSI info down
856 * in the domain hierarchy
857 * @dev: The device for which the domain should be created
858 * @domain: The domain in the hierarchy this op is being called on
859 * @msi_parent_domain: The IRQ_DOMAIN_FLAG_MSI_PARENT domain for the child to
860 * be created
861 * @msi_child_info: The MSI domain info of the IRQ_DOMAIN_FLAG_MSI_DEVICE
862 * domain to be created
863 *
864 * Return: true on success, false otherwise
865 *
866 * This is the most complex problem of per device MSI domains and the
867 * underlying interrupt domain hierarchy:
868 *
869 * The device domain to be initialized requests the broadest feature set
870 * possible and the underlying domain hierarchy puts restrictions on it.
871 *
872 * That's trivial for a simple parent->child relationship, but it gets
873 * interesting with an intermediate domain: root->parent->child. The
874 * intermediate 'parent' can expand the capabilities which the 'root'
875 * domain is providing. So that creates a classic hen and egg problem:
876 * Which entity is doing the restrictions/expansions?
877 *
878 * One solution is to let the root domain handle the initialization that's
879 * why there is the @domain and the @msi_parent_domain pointer.
880 */
881bool msi_parent_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
882 struct irq_domain *msi_parent_domain,
883 struct msi_domain_info *msi_child_info)
884{
885 struct irq_domain *parent = domain->parent;
886
887 if (WARN_ON_ONCE(!parent || !parent->msi_parent_ops ||
888 !parent->msi_parent_ops->init_dev_msi_info))
889 return false;
890
891 return parent->msi_parent_ops->init_dev_msi_info(dev, parent, msi_parent_domain,
892 msi_child_info);
893}
894
895/**
896 * msi_create_device_irq_domain - Create a device MSI interrupt domain
897 * @dev: Pointer to the device
898 * @domid: Domain id
899 * @template: MSI domain info bundle used as template
900 * @hwsize: Maximum number of MSI table entries (0 if unknown or unlimited)
901 * @domain_data: Optional pointer to domain specific data which is set in
902 * msi_domain_info::data
903 * @chip_data: Optional pointer to chip specific data which is set in
904 * msi_domain_info::chip_data
905 *
906 * Return: True on success, false otherwise
907 *
908 * There is no firmware node required for this interface because the per
909 * device domains are software constructs which are actually closer to the
910 * hardware reality than any firmware can describe them.
911 *
912 * The domain name and the irq chip name for a MSI device domain are
913 * composed by: "$(PREFIX)$(CHIPNAME)-$(DEVNAME)"
914 *
915 * $PREFIX: Optional prefix provided by the underlying MSI parent domain
916 * via msi_parent_ops::prefix. If that pointer is NULL the prefix
917 * is empty.
918 * $CHIPNAME: The name of the irq_chip in @template
919 * $DEVNAME: The name of the device
920 *
921 * This results in understandable chip names and hardware interrupt numbers
922 * in e.g. /proc/interrupts
923 *
924 * PCI-MSI-0000:00:1c.0 0-edge Parent domain has no prefix
925 * IR-PCI-MSI-0000:00:1c.4 0-edge Same with interrupt remapping prefix 'IR-'
926 *
927 * IR-PCI-MSIX-0000:3d:00.0 0-edge Hardware interrupt numbers reflect
928 * IR-PCI-MSIX-0000:3d:00.0 1-edge the real MSI-X index on that device
929 * IR-PCI-MSIX-0000:3d:00.0 2-edge
930 *
931 * On IMS domains the hardware interrupt number is either a table entry
932 * index or a purely software managed index but it is guaranteed to be
933 * unique.
934 *
935 * The domain pointer is stored in @dev::msi::data::__irqdomains[]. All
936 * subsequent operations on the domain depend on the domain id.
937 *
938 * The domain is automatically freed when the device is removed via devres
939 * in the context of @dev::msi::data freeing, but it can also be
940 * independently removed via @msi_remove_device_irq_domain().
941 */
942bool msi_create_device_irq_domain(struct device *dev, unsigned int domid,
943 const struct msi_domain_template *template,
944 unsigned int hwsize, void *domain_data,
945 void *chip_data)
946{
947 struct irq_domain *domain, *parent = dev->msi.domain;
948 const struct msi_parent_ops *pops;
949 struct msi_domain_template *bundle;
950 struct fwnode_handle *fwnode;
951
952 if (!irq_domain_is_msi_parent(parent))
953 return false;
954
955 if (domid >= MSI_MAX_DEVICE_IRQDOMAINS)
956 return false;
957
958 bundle = kmemdup(template, sizeof(*bundle), GFP_KERNEL);
959 if (!bundle)
960 return false;
961
962 bundle->info.hwsize = hwsize;
963 bundle->info.chip = &bundle->chip;
964 bundle->info.ops = &bundle->ops;
965 bundle->info.data = domain_data;
966 bundle->info.chip_data = chip_data;
967
968 pops = parent->msi_parent_ops;
969 snprintf(bundle->name, sizeof(bundle->name), "%s%s-%s",
970 pops->prefix ? : "", bundle->chip.name, dev_name(dev));
971 bundle->chip.name = bundle->name;
972
973 fwnode = irq_domain_alloc_named_fwnode(bundle->name);
974 if (!fwnode)
975 goto free_bundle;
976
977 if (msi_setup_device_data(dev))
978 goto free_fwnode;
979
980 msi_lock_descs(dev);
981
982 if (WARN_ON_ONCE(msi_get_device_domain(dev, domid)))
983 goto fail;
984
985 if (!pops->init_dev_msi_info(dev, parent, parent, &bundle->info))
986 goto fail;
987
988 domain = __msi_create_irq_domain(fwnode, &bundle->info, IRQ_DOMAIN_FLAG_MSI_DEVICE, parent);
989 if (!domain)
990 goto fail;
991
992 domain->dev = dev;
993 dev->msi.data->__domains[domid].domain = domain;
994 msi_unlock_descs(dev);
995 return true;
996
997fail:
998 msi_unlock_descs(dev);
999free_fwnode:
1000 irq_domain_free_fwnode(fwnode);
1001free_bundle:
1002 kfree(bundle);
1003 return false;
1004}
1005
1006/**
1007 * msi_remove_device_irq_domain - Free a device MSI interrupt domain
1008 * @dev: Pointer to the device
1009 * @domid: Domain id
1010 */
1011void msi_remove_device_irq_domain(struct device *dev, unsigned int domid)
1012{
1013 struct fwnode_handle *fwnode = NULL;
1014 struct msi_domain_info *info;
1015 struct irq_domain *domain;
1016
1017 msi_lock_descs(dev);
1018
1019 domain = msi_get_device_domain(dev, domid);
1020
1021 if (!domain || !irq_domain_is_msi_device(domain))
1022 goto unlock;
1023
1024 dev->msi.data->__domains[domid].domain = NULL;
1025 info = domain->host_data;
1026 if (irq_domain_is_msi_device(domain))
1027 fwnode = domain->fwnode;
1028 irq_domain_remove(domain);
1029 irq_domain_free_fwnode(fwnode);
1030 kfree(container_of(info, struct msi_domain_template, info));
1031
1032unlock:
1033 msi_unlock_descs(dev);
1034}
1035
1036/**
1037 * msi_match_device_irq_domain - Match a device irq domain against a bus token
1038 * @dev: Pointer to the device
1039 * @domid: Domain id
1040 * @bus_token: Bus token to match against the domain bus token
1041 *
1042 * Return: True if device domain exists and bus tokens match.
1043 */
1044bool msi_match_device_irq_domain(struct device *dev, unsigned int domid,
1045 enum irq_domain_bus_token bus_token)
1046{
1047 struct msi_domain_info *info;
1048 struct irq_domain *domain;
1049 bool ret = false;
1050
1051 msi_lock_descs(dev);
1052 domain = msi_get_device_domain(dev, domid);
1053 if (domain && irq_domain_is_msi_device(domain)) {
1054 info = domain->host_data;
1055 ret = info->bus_token == bus_token;
1056 }
1057 msi_unlock_descs(dev);
1058 return ret;
1059}
1060
1061int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,
1062 int nvec, msi_alloc_info_t *arg)
1063{
1064 struct msi_domain_info *info = domain->host_data;
1065 struct msi_domain_ops *ops = info->ops;
1066
1067 return ops->msi_prepare(domain, dev, nvec, arg);
1068}
1069
1070int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
1071 int virq_base, int nvec, msi_alloc_info_t *arg)
1072{
1073 struct msi_domain_info *info = domain->host_data;
1074 struct msi_domain_ops *ops = info->ops;
1075 struct msi_ctrl ctrl = {
1076 .domid = MSI_DEFAULT_DOMAIN,
1077 .first = virq_base,
1078 .last = virq_base + nvec - 1,
1079 };
1080 struct msi_desc *desc;
1081 struct xarray *xa;
1082 int ret, virq;
1083
1084 msi_lock_descs(dev);
1085
1086 if (!msi_ctrl_valid(dev, &ctrl)) {
1087 ret = -EINVAL;
1088 goto unlock;
1089 }
1090
1091 ret = msi_domain_add_simple_msi_descs(dev, &ctrl);
1092 if (ret)
1093 goto unlock;
1094
1095 xa = &dev->msi.data->__domains[ctrl.domid].store;
1096
1097 for (virq = virq_base; virq < virq_base + nvec; virq++) {
1098 desc = xa_load(xa, virq);
1099 desc->irq = virq;
1100
1101 ops->set_desc(arg, desc);
1102 ret = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
1103 if (ret)
1104 goto fail;
1105
1106 irq_set_msi_desc(virq, desc);
1107 }
1108 msi_unlock_descs(dev);
1109 return 0;
1110
1111fail:
1112 for (--virq; virq >= virq_base; virq--) {
1113 msi_domain_depopulate_descs(dev, virq, 1);
1114 irq_domain_free_irqs_common(domain, virq, 1);
1115 }
1116 msi_domain_free_descs(dev, &ctrl);
1117unlock:
1118 msi_unlock_descs(dev);
1119 return ret;
1120}
1121
1122void msi_domain_depopulate_descs(struct device *dev, int virq_base, int nvec)
1123{
1124 struct msi_ctrl ctrl = {
1125 .domid = MSI_DEFAULT_DOMAIN,
1126 .first = virq_base,
1127 .last = virq_base + nvec - 1,
1128 };
1129 struct msi_desc *desc;
1130 struct xarray *xa;
1131 unsigned long idx;
1132
1133 if (!msi_ctrl_valid(dev, &ctrl))
1134 return;
1135
1136 xa = &dev->msi.data->__domains[ctrl.domid].store;
1137 xa_for_each_range(xa, idx, desc, ctrl.first, ctrl.last)
1138 desc->irq = 0;
1139}
1140
1141/*
1142 * Carefully check whether the device can use reservation mode. If
1143 * reservation mode is enabled then the early activation will assign a
1144 * dummy vector to the device. If the PCI/MSI device does not support
1145 * masking of the entry then this can result in spurious interrupts when
1146 * the device driver is not absolutely careful. But even then a malfunction
1147 * of the hardware could result in a spurious interrupt on the dummy vector
1148 * and render the device unusable. If the entry can be masked then the core
1149 * logic will prevent the spurious interrupt and reservation mode can be
1150 * used. For now reservation mode is restricted to PCI/MSI.
1151 */
1152static bool msi_check_reservation_mode(struct irq_domain *domain,
1153 struct msi_domain_info *info,
1154 struct device *dev)
1155{
1156 struct msi_desc *desc;
1157
1158 switch(domain->bus_token) {
1159 case DOMAIN_BUS_PCI_MSI:
1160 case DOMAIN_BUS_PCI_DEVICE_MSI:
1161 case DOMAIN_BUS_PCI_DEVICE_MSIX:
1162 case DOMAIN_BUS_VMD_MSI:
1163 break;
1164 default:
1165 return false;
1166 }
1167
1168 if (!(info->flags & MSI_FLAG_MUST_REACTIVATE))
1169 return false;
1170
1171 if (IS_ENABLED(CONFIG_PCI_MSI) && pci_msi_ignore_mask)
1172 return false;
1173
1174 /*
1175 * Checking the first MSI descriptor is sufficient. MSIX supports
1176 * masking and MSI does so when the can_mask attribute is set.
1177 */
1178 desc = msi_first_desc(dev, MSI_DESC_ALL);
1179 return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask;
1180}
1181
1182static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc,
1183 int allocated)
1184{
1185 switch(domain->bus_token) {
1186 case DOMAIN_BUS_PCI_MSI:
1187 case DOMAIN_BUS_PCI_DEVICE_MSI:
1188 case DOMAIN_BUS_PCI_DEVICE_MSIX:
1189 case DOMAIN_BUS_VMD_MSI:
1190 if (IS_ENABLED(CONFIG_PCI_MSI))
1191 break;
1192 fallthrough;
1193 default:
1194 return -ENOSPC;
1195 }
1196
1197 /* Let a failed PCI multi MSI allocation retry */
1198 if (desc->nvec_used > 1)
1199 return 1;
1200
1201 /* If there was a successful allocation let the caller know */
1202 return allocated ? allocated : -ENOSPC;
1203}
1204
1205#define VIRQ_CAN_RESERVE 0x01
1206#define VIRQ_ACTIVATE 0x02
1207
1208static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflags)
1209{
1210 struct irq_data *irqd = irq_domain_get_irq_data(domain, virq);
1211 int ret;
1212
1213 if (!(vflags & VIRQ_CAN_RESERVE)) {
1214 irqd_clr_can_reserve(irqd);
1215
1216 /*
1217 * If the interrupt is managed but no CPU is available to
1218 * service it, shut it down until better times. Note that
1219 * we only do this on the !RESERVE path as x86 (the only
1220 * architecture using this flag) deals with this in a
1221 * different way by using a catch-all vector.
1222 */
1223 if ((vflags & VIRQ_ACTIVATE) &&
1224 irqd_affinity_is_managed(irqd) &&
1225 !cpumask_intersects(irq_data_get_affinity_mask(irqd),
1226 cpu_online_mask)) {
1227 irqd_set_managed_shutdown(irqd);
1228 return 0;
1229 }
1230 }
1231
1232 if (!(vflags & VIRQ_ACTIVATE))
1233 return 0;
1234
1235 ret = irq_domain_activate_irq(irqd, vflags & VIRQ_CAN_RESERVE);
1236 if (ret)
1237 return ret;
1238 /*
1239 * If the interrupt uses reservation mode, clear the activated bit
1240 * so request_irq() will assign the final vector.
1241 */
1242 if (vflags & VIRQ_CAN_RESERVE)
1243 irqd_clr_activated(irqd);
1244 return 0;
1245}
1246
1247static int __msi_domain_alloc_irqs(struct device *dev, struct irq_domain *domain,
1248 struct msi_ctrl *ctrl)
1249{
1250 struct xarray *xa = &dev->msi.data->__domains[ctrl->domid].store;
1251 struct msi_domain_info *info = domain->host_data;
1252 struct msi_domain_ops *ops = info->ops;
1253 unsigned int vflags = 0, allocated = 0;
1254 msi_alloc_info_t arg = { };
1255 struct msi_desc *desc;
1256 unsigned long idx;
1257 int i, ret, virq;
1258
1259 ret = msi_domain_prepare_irqs(domain, dev, ctrl->nirqs, &arg);
1260 if (ret)
1261 return ret;
1262
1263 /*
1264 * This flag is set by the PCI layer as we need to activate
1265 * the MSI entries before the PCI layer enables MSI in the
1266 * card. Otherwise the card latches a random msi message.
1267 */
1268 if (info->flags & MSI_FLAG_ACTIVATE_EARLY)
1269 vflags |= VIRQ_ACTIVATE;
1270
1271 /*
1272 * Interrupt can use a reserved vector and will not occupy
1273 * a real device vector until the interrupt is requested.
1274 */
1275 if (msi_check_reservation_mode(domain, info, dev))
1276 vflags |= VIRQ_CAN_RESERVE;
1277
1278 xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
1279 if (!msi_desc_match(desc, MSI_DESC_NOTASSOCIATED))
1280 continue;
1281
1282 /* This should return -ECONFUSED... */
1283 if (WARN_ON_ONCE(allocated >= ctrl->nirqs))
1284 return -EINVAL;
1285
1286 if (ops->prepare_desc)
1287 ops->prepare_desc(domain, &arg, desc);
1288
1289 ops->set_desc(&arg, desc);
1290
1291 virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used,
1292 dev_to_node(dev), &arg, false,
1293 desc->affinity);
1294 if (virq < 0)
1295 return msi_handle_pci_fail(domain, desc, allocated);
1296
1297 for (i = 0; i < desc->nvec_used; i++) {
1298 irq_set_msi_desc_off(virq, i, desc);
1299 irq_debugfs_copy_devname(virq + i, dev);
1300 ret = msi_init_virq(domain, virq + i, vflags);
1301 if (ret)
1302 return ret;
1303 }
1304 if (info->flags & MSI_FLAG_DEV_SYSFS) {
1305 ret = msi_sysfs_populate_desc(dev, desc);
1306 if (ret)
1307 return ret;
1308 }
1309 allocated++;
1310 }
1311 return 0;
1312}
1313
1314static int msi_domain_alloc_simple_msi_descs(struct device *dev,
1315 struct msi_domain_info *info,
1316 struct msi_ctrl *ctrl)
1317{
1318 if (!(info->flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS))
1319 return 0;
1320
1321 return msi_domain_add_simple_msi_descs(dev, ctrl);
1322}
1323
1324static int __msi_domain_alloc_locked(struct device *dev, struct msi_ctrl *ctrl)
1325{
1326 struct msi_domain_info *info;
1327 struct msi_domain_ops *ops;
1328 struct irq_domain *domain;
1329 int ret;
1330
1331 if (!msi_ctrl_valid(dev, ctrl))
1332 return -EINVAL;
1333
1334 domain = msi_get_device_domain(dev, ctrl->domid);
1335 if (!domain)
1336 return -ENODEV;
1337
1338 info = domain->host_data;
1339
1340 ret = msi_domain_alloc_simple_msi_descs(dev, info, ctrl);
1341 if (ret)
1342 return ret;
1343
1344 ops = info->ops;
1345 if (ops->domain_alloc_irqs)
1346 return ops->domain_alloc_irqs(domain, dev, ctrl->nirqs);
1347
1348 return __msi_domain_alloc_irqs(dev, domain, ctrl);
1349}
1350
1351static int msi_domain_alloc_locked(struct device *dev, struct msi_ctrl *ctrl)
1352{
1353 int ret = __msi_domain_alloc_locked(dev, ctrl);
1354
1355 if (ret)
1356 msi_domain_free_locked(dev, ctrl);
1357 return ret;
1358}
1359
1360/**
1361 * msi_domain_alloc_irqs_range_locked - Allocate interrupts from a MSI interrupt domain
1362 * @dev: Pointer to device struct of the device for which the interrupts
1363 * are allocated
1364 * @domid: Id of the interrupt domain to operate on
1365 * @first: First index to allocate (inclusive)
1366 * @last: Last index to allocate (inclusive)
1367 *
1368 * Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
1369 * pair. Use this for MSI irqdomains which implement their own descriptor
1370 * allocation/free.
1371 *
1372 * Return: %0 on success or an error code.
1373 */
1374int msi_domain_alloc_irqs_range_locked(struct device *dev, unsigned int domid,
1375 unsigned int first, unsigned int last)
1376{
1377 struct msi_ctrl ctrl = {
1378 .domid = domid,
1379 .first = first,
1380 .last = last,
1381 .nirqs = last + 1 - first,
1382 };
1383
1384 return msi_domain_alloc_locked(dev, &ctrl);
1385}
1386
1387/**
1388 * msi_domain_alloc_irqs_range - Allocate interrupts from a MSI interrupt domain
1389 * @dev: Pointer to device struct of the device for which the interrupts
1390 * are allocated
1391 * @domid: Id of the interrupt domain to operate on
1392 * @first: First index to allocate (inclusive)
1393 * @last: Last index to allocate (inclusive)
1394 *
1395 * Return: %0 on success or an error code.
1396 */
1397int msi_domain_alloc_irqs_range(struct device *dev, unsigned int domid,
1398 unsigned int first, unsigned int last)
1399{
1400 int ret;
1401
1402 msi_lock_descs(dev);
1403 ret = msi_domain_alloc_irqs_range_locked(dev, domid, first, last);
1404 msi_unlock_descs(dev);
1405 return ret;
1406}
1407
1408/**
1409 * msi_domain_alloc_irqs_all_locked - Allocate all interrupts from a MSI interrupt domain
1410 *
1411 * @dev: Pointer to device struct of the device for which the interrupts
1412 * are allocated
1413 * @domid: Id of the interrupt domain to operate on
1414 * @nirqs: The number of interrupts to allocate
1415 *
1416 * This function scans all MSI descriptors of the MSI domain and allocates interrupts
1417 * for all unassigned ones. That function is to be used for MSI domain usage where
1418 * the descriptor allocation is handled at the call site, e.g. PCI/MSI[X].
1419 *
1420 * Return: %0 on success or an error code.
1421 */
1422int msi_domain_alloc_irqs_all_locked(struct device *dev, unsigned int domid, int nirqs)
1423{
1424 struct msi_ctrl ctrl = {
1425 .domid = domid,
1426 .first = 0,
1427 .last = msi_domain_get_hwsize(dev, domid) - 1,
1428 .nirqs = nirqs,
1429 };
1430
1431 return msi_domain_alloc_locked(dev, &ctrl);
1432}
1433
1434/**
1435 * msi_domain_alloc_irq_at - Allocate an interrupt from a MSI interrupt domain at
1436 * a given index - or at the next free index
1437 *
1438 * @dev: Pointer to device struct of the device for which the interrupts
1439 * are allocated
1440 * @domid: Id of the interrupt domain to operate on
1441 * @index: Index for allocation. If @index == %MSI_ANY_INDEX the allocation
1442 * uses the next free index.
1443 * @affdesc: Optional pointer to an interrupt affinity descriptor structure
1444 * @icookie: Optional pointer to a domain specific per instance cookie. If
1445 * non-NULL the content of the cookie is stored in msi_desc::data.
1446 * Must be NULL for MSI-X allocations
1447 *
1448 * This requires a MSI interrupt domain which lets the core code manage the
1449 * MSI descriptors.
1450 *
1451 * Return: struct msi_map
1452 *
1453 * On success msi_map::index contains the allocated index number and
1454 * msi_map::virq the corresponding Linux interrupt number
1455 *
1456 * On failure msi_map::index contains the error code and msi_map::virq
1457 * is %0.
1458 */
1459struct msi_map msi_domain_alloc_irq_at(struct device *dev, unsigned int domid, unsigned int index,
1460 const struct irq_affinity_desc *affdesc,
1461 union msi_instance_cookie *icookie)
1462{
1463 struct msi_ctrl ctrl = { .domid = domid, .nirqs = 1, };
1464 struct irq_domain *domain;
1465 struct msi_map map = { };
1466 struct msi_desc *desc;
1467 int ret;
1468
1469 msi_lock_descs(dev);
1470 domain = msi_get_device_domain(dev, domid);
1471 if (!domain) {
1472 map.index = -ENODEV;
1473 goto unlock;
1474 }
1475
1476 desc = msi_alloc_desc(dev, 1, affdesc);
1477 if (!desc) {
1478 map.index = -ENOMEM;
1479 goto unlock;
1480 }
1481
1482 if (icookie)
1483 desc->data.icookie = *icookie;
1484
1485 ret = msi_insert_desc(dev, desc, domid, index);
1486 if (ret) {
1487 map.index = ret;
1488 goto unlock;
1489 }
1490
1491 ctrl.first = ctrl.last = desc->msi_index;
1492
1493 ret = __msi_domain_alloc_irqs(dev, domain, &ctrl);
1494 if (ret) {
1495 map.index = ret;
1496 msi_domain_free_locked(dev, &ctrl);
1497 } else {
1498 map.index = desc->msi_index;
1499 map.virq = desc->irq;
1500 }
1501unlock:
1502 msi_unlock_descs(dev);
1503 return map;
1504}
1505
1506static void __msi_domain_free_irqs(struct device *dev, struct irq_domain *domain,
1507 struct msi_ctrl *ctrl)
1508{
1509 struct xarray *xa = &dev->msi.data->__domains[ctrl->domid].store;
1510 struct msi_domain_info *info = domain->host_data;
1511 struct irq_data *irqd;
1512 struct msi_desc *desc;
1513 unsigned long idx;
1514 int i;
1515
1516 xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
1517 /* Only handle MSI entries which have an interrupt associated */
1518 if (!msi_desc_match(desc, MSI_DESC_ASSOCIATED))
1519 continue;
1520
1521 /* Make sure all interrupts are deactivated */
1522 for (i = 0; i < desc->nvec_used; i++) {
1523 irqd = irq_domain_get_irq_data(domain, desc->irq + i);
1524 if (irqd && irqd_is_activated(irqd))
1525 irq_domain_deactivate_irq(irqd);
1526 }
1527
1528 irq_domain_free_irqs(desc->irq, desc->nvec_used);
1529 if (info->flags & MSI_FLAG_DEV_SYSFS)
1530 msi_sysfs_remove_desc(dev, desc);
1531 desc->irq = 0;
1532 }
1533}
1534
1535static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl)
1536{
1537 struct msi_domain_info *info;
1538 struct msi_domain_ops *ops;
1539 struct irq_domain *domain;
1540
1541 if (!msi_ctrl_valid(dev, ctrl))
1542 return;
1543
1544 domain = msi_get_device_domain(dev, ctrl->domid);
1545 if (!domain)
1546 return;
1547
1548 info = domain->host_data;
1549 ops = info->ops;
1550
1551 if (ops->domain_free_irqs)
1552 ops->domain_free_irqs(domain, dev);
1553 else
1554 __msi_domain_free_irqs(dev, domain, ctrl);
1555
1556 if (ops->msi_post_free)
1557 ops->msi_post_free(domain, dev);
1558
1559 if (info->flags & MSI_FLAG_FREE_MSI_DESCS)
1560 msi_domain_free_descs(dev, ctrl);
1561}
1562
1563/**
1564 * msi_domain_free_irqs_range_locked - Free a range of interrupts from a MSI interrupt domain
1565 * associated to @dev with msi_lock held
1566 * @dev: Pointer to device struct of the device for which the interrupts
1567 * are freed
1568 * @domid: Id of the interrupt domain to operate on
1569 * @first: First index to free (inclusive)
1570 * @last: Last index to free (inclusive)
1571 */
1572void msi_domain_free_irqs_range_locked(struct device *dev, unsigned int domid,
1573 unsigned int first, unsigned int last)
1574{
1575 struct msi_ctrl ctrl = {
1576 .domid = domid,
1577 .first = first,
1578 .last = last,
1579 };
1580 msi_domain_free_locked(dev, &ctrl);
1581}
1582
1583/**
1584 * msi_domain_free_irqs_range - Free a range of interrupts from a MSI interrupt domain
1585 * associated to @dev
1586 * @dev: Pointer to device struct of the device for which the interrupts
1587 * are freed
1588 * @domid: Id of the interrupt domain to operate on
1589 * @first: First index to free (inclusive)
1590 * @last: Last index to free (inclusive)
1591 */
1592void msi_domain_free_irqs_range(struct device *dev, unsigned int domid,
1593 unsigned int first, unsigned int last)
1594{
1595 msi_lock_descs(dev);
1596 msi_domain_free_irqs_range_locked(dev, domid, first, last);
1597 msi_unlock_descs(dev);
1598}
1599
1600/**
1601 * msi_domain_free_irqs_all_locked - Free all interrupts from a MSI interrupt domain
1602 * associated to a device
1603 * @dev: Pointer to device struct of the device for which the interrupts
1604 * are freed
1605 * @domid: The id of the domain to operate on
1606 *
1607 * Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
1608 * pair. Use this for MSI irqdomains which implement their own vector
1609 * allocation.
1610 */
1611void msi_domain_free_irqs_all_locked(struct device *dev, unsigned int domid)
1612{
1613 msi_domain_free_irqs_range_locked(dev, domid, 0,
1614 msi_domain_get_hwsize(dev, domid) - 1);
1615}
1616
1617/**
1618 * msi_domain_free_irqs_all - Free all interrupts from a MSI interrupt domain
1619 * associated to a device
1620 * @dev: Pointer to device struct of the device for which the interrupts
1621 * are freed
1622 * @domid: The id of the domain to operate on
1623 */
1624void msi_domain_free_irqs_all(struct device *dev, unsigned int domid)
1625{
1626 msi_lock_descs(dev);
1627 msi_domain_free_irqs_all_locked(dev, domid);
1628 msi_unlock_descs(dev);
1629}
1630
1631/**
1632 * msi_get_domain_info - Get the MSI interrupt domain info for @domain
1633 * @domain: The interrupt domain to retrieve data from
1634 *
1635 * Return: the pointer to the msi_domain_info stored in @domain->host_data.
1636 */
1637struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
1638{
1639 return (struct msi_domain_info *)domain->host_data;
1640}
1641
1642/**
1643 * msi_device_has_isolated_msi - True if the device has isolated MSI
1644 * @dev: The device to check
1645 *
1646 * Isolated MSI means that HW modeled by an irq_domain on the path from the
1647 * initiating device to the CPU will validate that the MSI message specifies an
1648 * interrupt number that the device is authorized to trigger. This must block
1649 * devices from triggering interrupts they are not authorized to trigger.
1650 * Currently authorization means the MSI vector is one assigned to the device.
1651 *
1652 * This is interesting for securing VFIO use cases where a rouge MSI (eg created
1653 * by abusing a normal PCI MemWr DMA) must not allow the VFIO userspace to
1654 * impact outside its security domain, eg userspace triggering interrupts on
1655 * kernel drivers, a VM triggering interrupts on the hypervisor, or a VM
1656 * triggering interrupts on another VM.
1657 */
1658bool msi_device_has_isolated_msi(struct device *dev)
1659{
1660 struct irq_domain *domain = dev_get_msi_domain(dev);
1661
1662 for (; domain; domain = domain->parent)
1663 if (domain->flags & IRQ_DOMAIN_FLAG_ISOLATED_MSI)
1664 return true;
1665 return arch_is_isolated_msi();
1666}
1667EXPORT_SYMBOL_GPL(msi_device_has_isolated_msi);