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/device.h> 12 #include <linux/irq.h> 13 #include <linux/irqdomain.h> 14 #include <linux/msi.h> 15 #include <linux/mutex.h> 16 #include <linux/pci.h> 17 #include <linux/slab.h> 18 #include <linux/seq_file.h> 19 #include <linux/sysfs.h> 20 #include <linux/types.h> 21 #include <linux/xarray.h> 22 23 #include "internals.h" 24 25 /** 26 * struct msi_device_data - MSI per device data 27 * @properties: MSI properties which are interesting to drivers 28 * @mutex: Mutex protecting the MSI descriptor store 29 * @__domains: Internal data for per device MSI domains 30 * @__iter_idx: Index to search the next entry for iterators 31 */ 32 struct msi_device_data { 33 unsigned long properties; 34 struct mutex mutex; 35 struct msi_dev_domain __domains[MSI_MAX_DEVICE_IRQDOMAINS]; 36 unsigned long __iter_idx; 37 }; 38 39 /** 40 * struct msi_ctrl - MSI internal management control structure 41 * @domid: ID of the domain on which management operations should be done 42 * @first: First (hardware) slot index to operate on 43 * @last: Last (hardware) slot index to operate on 44 * @nirqs: The number of Linux interrupts to allocate. Can be larger 45 * than the range due to PCI/multi-MSI. 46 */ 47 struct msi_ctrl { 48 unsigned int domid; 49 unsigned int first; 50 unsigned int last; 51 unsigned int nirqs; 52 }; 53 54 /* Invalid Xarray index which is outside of any searchable range */ 55 #define MSI_XA_MAX_INDEX (ULONG_MAX - 1) 56 /* The maximum domain size */ 57 #define MSI_XA_DOMAIN_SIZE (MSI_MAX_INDEX + 1) 58 59 static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl); 60 static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid); 61 static inline int msi_sysfs_create_group(struct device *dev); 62 static int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev, 63 int nvec, msi_alloc_info_t *arg); 64 65 /** 66 * msi_alloc_desc - Allocate an initialized msi_desc 67 * @dev: Pointer to the device for which this is allocated 68 * @nvec: The number of vectors used in this entry 69 * @affinity: Optional pointer to an affinity mask array size of @nvec 70 * 71 * If @affinity is not %NULL then an affinity array[@nvec] is allocated 72 * and the affinity masks and flags from @affinity are copied. 73 * 74 * Return: pointer to allocated &msi_desc on success or %NULL on failure 75 */ 76 static struct msi_desc *msi_alloc_desc(struct device *dev, int nvec, 77 const struct irq_affinity_desc *affinity) 78 { 79 struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL); 80 81 if (!desc) 82 return NULL; 83 84 desc->dev = dev; 85 desc->nvec_used = nvec; 86 if (affinity) { 87 desc->affinity = kmemdup_array(affinity, nvec, sizeof(*desc->affinity), GFP_KERNEL); 88 if (!desc->affinity) { 89 kfree(desc); 90 return NULL; 91 } 92 } 93 return desc; 94 } 95 96 static void msi_free_desc(struct msi_desc *desc) 97 { 98 kfree(desc->affinity); 99 kfree(desc); 100 } 101 102 static int msi_insert_desc(struct device *dev, struct msi_desc *desc, 103 unsigned int domid, unsigned int index) 104 { 105 struct msi_device_data *md = dev->msi.data; 106 struct xarray *xa = &md->__domains[domid].store; 107 unsigned int hwsize; 108 int ret; 109 110 hwsize = msi_domain_get_hwsize(dev, domid); 111 112 if (index == MSI_ANY_INDEX) { 113 struct xa_limit limit = { .min = 0, .max = hwsize - 1 }; 114 unsigned int index; 115 116 /* Let the xarray allocate a free index within the limit */ 117 ret = xa_alloc(xa, &index, desc, limit, GFP_KERNEL); 118 if (ret) 119 goto fail; 120 121 desc->msi_index = index; 122 return 0; 123 } else { 124 if (index >= hwsize) { 125 ret = -ERANGE; 126 goto fail; 127 } 128 129 desc->msi_index = index; 130 ret = xa_insert(xa, index, desc, GFP_KERNEL); 131 if (ret) 132 goto fail; 133 return 0; 134 } 135 fail: 136 msi_free_desc(desc); 137 return ret; 138 } 139 140 /** 141 * msi_domain_insert_msi_desc - Allocate and initialize a MSI descriptor and 142 * insert it at @init_desc->msi_index 143 * 144 * @dev: Pointer to the device for which the descriptor is allocated 145 * @domid: The id of the interrupt domain to which the desriptor is added 146 * @init_desc: Pointer to an MSI descriptor to initialize the new descriptor 147 * 148 * Return: 0 on success or an appropriate failure code. 149 */ 150 int msi_domain_insert_msi_desc(struct device *dev, unsigned int domid, 151 struct msi_desc *init_desc) 152 { 153 struct msi_desc *desc; 154 155 lockdep_assert_held(&dev->msi.data->mutex); 156 157 desc = msi_alloc_desc(dev, init_desc->nvec_used, init_desc->affinity); 158 if (!desc) 159 return -ENOMEM; 160 161 /* Copy type specific data to the new descriptor. */ 162 desc->pci = init_desc->pci; 163 164 return msi_insert_desc(dev, desc, domid, init_desc->msi_index); 165 } 166 167 static bool msi_desc_match(struct msi_desc *desc, enum msi_desc_filter filter) 168 { 169 switch (filter) { 170 case MSI_DESC_ALL: 171 return true; 172 case MSI_DESC_NOTASSOCIATED: 173 return !desc->irq; 174 case MSI_DESC_ASSOCIATED: 175 return !!desc->irq; 176 } 177 WARN_ON_ONCE(1); 178 return false; 179 } 180 181 static bool msi_ctrl_valid(struct device *dev, struct msi_ctrl *ctrl) 182 { 183 unsigned int hwsize; 184 185 if (WARN_ON_ONCE(ctrl->domid >= MSI_MAX_DEVICE_IRQDOMAINS || 186 (dev->msi.domain && 187 !dev->msi.data->__domains[ctrl->domid].domain))) 188 return false; 189 190 hwsize = msi_domain_get_hwsize(dev, ctrl->domid); 191 if (WARN_ON_ONCE(ctrl->first > ctrl->last || 192 ctrl->first >= hwsize || 193 ctrl->last >= hwsize)) 194 return false; 195 return true; 196 } 197 198 static void msi_domain_free_descs(struct device *dev, struct msi_ctrl *ctrl) 199 { 200 struct msi_desc *desc; 201 struct xarray *xa; 202 unsigned long idx; 203 204 lockdep_assert_held(&dev->msi.data->mutex); 205 206 if (!msi_ctrl_valid(dev, ctrl)) 207 return; 208 209 xa = &dev->msi.data->__domains[ctrl->domid].store; 210 xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) { 211 xa_erase(xa, idx); 212 213 /* Leak the descriptor when it is still referenced */ 214 if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED))) 215 continue; 216 msi_free_desc(desc); 217 } 218 } 219 220 /** 221 * msi_domain_free_msi_descs_range - Free a range of MSI descriptors of a device in an irqdomain 222 * @dev: Device for which to free the descriptors 223 * @domid: Id of the domain to operate on 224 * @first: Index to start freeing from (inclusive) 225 * @last: Last index to be freed (inclusive) 226 */ 227 void msi_domain_free_msi_descs_range(struct device *dev, unsigned int domid, 228 unsigned int first, unsigned int last) 229 { 230 struct msi_ctrl ctrl = { 231 .domid = domid, 232 .first = first, 233 .last = last, 234 }; 235 236 msi_domain_free_descs(dev, &ctrl); 237 } 238 239 /** 240 * msi_domain_add_simple_msi_descs - Allocate and initialize MSI descriptors 241 * @dev: Pointer to the device for which the descriptors are allocated 242 * @ctrl: Allocation control struct 243 * 244 * Return: 0 on success or an appropriate failure code. 245 */ 246 static int msi_domain_add_simple_msi_descs(struct device *dev, struct msi_ctrl *ctrl) 247 { 248 struct msi_desc *desc; 249 unsigned int idx; 250 int ret; 251 252 lockdep_assert_held(&dev->msi.data->mutex); 253 254 if (!msi_ctrl_valid(dev, ctrl)) 255 return -EINVAL; 256 257 for (idx = ctrl->first; idx <= ctrl->last; idx++) { 258 desc = msi_alloc_desc(dev, 1, NULL); 259 if (!desc) 260 goto fail_mem; 261 ret = msi_insert_desc(dev, desc, ctrl->domid, idx); 262 if (ret) 263 goto fail; 264 } 265 return 0; 266 267 fail_mem: 268 ret = -ENOMEM; 269 fail: 270 msi_domain_free_descs(dev, ctrl); 271 return ret; 272 } 273 274 void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) 275 { 276 *msg = entry->msg; 277 } 278 279 void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) 280 { 281 struct msi_desc *entry = irq_get_msi_desc(irq); 282 283 __get_cached_msi_msg(entry, msg); 284 } 285 EXPORT_SYMBOL_GPL(get_cached_msi_msg); 286 287 static void msi_device_data_release(struct device *dev, void *res) 288 { 289 struct msi_device_data *md = res; 290 int i; 291 292 for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++) { 293 msi_remove_device_irq_domain(dev, i); 294 WARN_ON_ONCE(!xa_empty(&md->__domains[i].store)); 295 xa_destroy(&md->__domains[i].store); 296 } 297 dev->msi.data = NULL; 298 } 299 300 /** 301 * msi_setup_device_data - Setup MSI device data 302 * @dev: Device for which MSI device data should be set up 303 * 304 * Return: 0 on success, appropriate error code otherwise 305 * 306 * This can be called more than once for @dev. If the MSI device data is 307 * already allocated the call succeeds. The allocated memory is 308 * automatically released when the device is destroyed. 309 */ 310 int msi_setup_device_data(struct device *dev) 311 { 312 struct msi_device_data *md; 313 int ret, i; 314 315 if (dev->msi.data) 316 return 0; 317 318 md = devres_alloc(msi_device_data_release, sizeof(*md), GFP_KERNEL); 319 if (!md) 320 return -ENOMEM; 321 322 ret = msi_sysfs_create_group(dev); 323 if (ret) { 324 devres_free(md); 325 return ret; 326 } 327 328 for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++) 329 xa_init_flags(&md->__domains[i].store, XA_FLAGS_ALLOC); 330 331 /* 332 * If @dev::msi::domain is set and is a global MSI domain, copy the 333 * pointer into the domain array so all code can operate on domain 334 * ids. The NULL pointer check is required to keep the legacy 335 * architecture specific PCI/MSI support working. 336 */ 337 if (dev->msi.domain && !irq_domain_is_msi_parent(dev->msi.domain)) 338 md->__domains[MSI_DEFAULT_DOMAIN].domain = dev->msi.domain; 339 340 mutex_init(&md->mutex); 341 dev->msi.data = md; 342 devres_add(dev, md); 343 return 0; 344 } 345 346 /** 347 * __msi_lock_descs - Lock the MSI descriptor storage of a device 348 * @dev: Device to operate on 349 * 350 * Internal function for guard(msi_descs_lock). Don't use in code. 351 */ 352 void __msi_lock_descs(struct device *dev) 353 { 354 mutex_lock(&dev->msi.data->mutex); 355 } 356 EXPORT_SYMBOL_GPL(__msi_lock_descs); 357 358 /** 359 * __msi_unlock_descs - Unlock the MSI descriptor storage of a device 360 * @dev: Device to operate on 361 * 362 * Internal function for guard(msi_descs_lock). Don't use in code. 363 */ 364 void __msi_unlock_descs(struct device *dev) 365 { 366 /* Invalidate the index which was cached by the iterator */ 367 dev->msi.data->__iter_idx = MSI_XA_MAX_INDEX; 368 mutex_unlock(&dev->msi.data->mutex); 369 } 370 EXPORT_SYMBOL_GPL(__msi_unlock_descs); 371 372 static struct msi_desc *msi_find_desc(struct msi_device_data *md, unsigned int domid, 373 enum msi_desc_filter filter) 374 { 375 struct xarray *xa = &md->__domains[domid].store; 376 struct msi_desc *desc; 377 378 xa_for_each_start(xa, md->__iter_idx, desc, md->__iter_idx) { 379 if (msi_desc_match(desc, filter)) 380 return desc; 381 } 382 md->__iter_idx = MSI_XA_MAX_INDEX; 383 return NULL; 384 } 385 386 /** 387 * msi_domain_first_desc - Get the first MSI descriptor of an irqdomain associated to a device 388 * @dev: Device to operate on 389 * @domid: The id of the interrupt domain which should be walked. 390 * @filter: Descriptor state filter 391 * 392 * Must be called with the MSI descriptor mutex held, i.e. msi_lock_descs() 393 * must be invoked before the call. 394 * 395 * Return: Pointer to the first MSI descriptor matching the search 396 * criteria, NULL if none found. 397 */ 398 struct msi_desc *msi_domain_first_desc(struct device *dev, unsigned int domid, 399 enum msi_desc_filter filter) 400 { 401 struct msi_device_data *md = dev->msi.data; 402 403 if (WARN_ON_ONCE(!md || domid >= MSI_MAX_DEVICE_IRQDOMAINS)) 404 return NULL; 405 406 lockdep_assert_held(&md->mutex); 407 408 md->__iter_idx = 0; 409 return msi_find_desc(md, domid, filter); 410 } 411 EXPORT_SYMBOL_GPL(msi_domain_first_desc); 412 413 /** 414 * msi_next_desc - Get the next MSI descriptor of a device 415 * @dev: Device to operate on 416 * @domid: The id of the interrupt domain which should be walked. 417 * @filter: Descriptor state filter 418 * 419 * The first invocation of msi_next_desc() has to be preceeded by a 420 * successful invocation of __msi_first_desc(). Consecutive invocations are 421 * only valid if the previous one was successful. All these operations have 422 * to be done within the same MSI mutex held region. 423 * 424 * Return: Pointer to the next MSI descriptor matching the search 425 * criteria, NULL if none found. 426 */ 427 struct msi_desc *msi_next_desc(struct device *dev, unsigned int domid, 428 enum msi_desc_filter filter) 429 { 430 struct msi_device_data *md = dev->msi.data; 431 432 if (WARN_ON_ONCE(!md || domid >= MSI_MAX_DEVICE_IRQDOMAINS)) 433 return NULL; 434 435 lockdep_assert_held(&md->mutex); 436 437 if (md->__iter_idx >= (unsigned long)MSI_MAX_INDEX) 438 return NULL; 439 440 md->__iter_idx++; 441 return msi_find_desc(md, domid, filter); 442 } 443 EXPORT_SYMBOL_GPL(msi_next_desc); 444 445 /** 446 * msi_domain_get_virq - Lookup the Linux interrupt number for a MSI index on a interrupt domain 447 * @dev: Device to operate on 448 * @domid: Domain ID of the interrupt domain associated to the device 449 * @index: MSI interrupt index to look for (0-based) 450 * 451 * Return: The Linux interrupt number on success (> 0), 0 if not found 452 */ 453 unsigned int msi_domain_get_virq(struct device *dev, unsigned int domid, unsigned int index) 454 { 455 struct msi_desc *desc; 456 bool pcimsi = false; 457 struct xarray *xa; 458 459 if (!dev->msi.data) 460 return 0; 461 462 if (WARN_ON_ONCE(index > MSI_MAX_INDEX || domid >= MSI_MAX_DEVICE_IRQDOMAINS)) 463 return 0; 464 465 /* This check is only valid for the PCI default MSI domain */ 466 if (dev_is_pci(dev) && domid == MSI_DEFAULT_DOMAIN) 467 pcimsi = to_pci_dev(dev)->msi_enabled; 468 469 guard(msi_descs_lock)(dev); 470 xa = &dev->msi.data->__domains[domid].store; 471 desc = xa_load(xa, pcimsi ? 0 : index); 472 if (desc && desc->irq) { 473 /* 474 * PCI-MSI has only one descriptor for multiple interrupts. 475 * PCI-MSIX and platform MSI use a descriptor per 476 * interrupt. 477 */ 478 if (!pcimsi) 479 return desc->irq; 480 if (index < desc->nvec_used) 481 return desc->irq + index; 482 } 483 return 0; 484 } 485 EXPORT_SYMBOL_GPL(msi_domain_get_virq); 486 487 #ifdef CONFIG_SYSFS 488 static struct attribute *msi_dev_attrs[] = { 489 NULL 490 }; 491 492 static const struct attribute_group msi_irqs_group = { 493 .name = "msi_irqs", 494 .attrs = msi_dev_attrs, 495 }; 496 497 static inline int msi_sysfs_create_group(struct device *dev) 498 { 499 return devm_device_add_group(dev, &msi_irqs_group); 500 } 501 502 static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr, 503 char *buf) 504 { 505 /* MSI vs. MSIX is per device not per interrupt */ 506 bool is_msix = dev_is_pci(dev) ? to_pci_dev(dev)->msix_enabled : false; 507 508 return sysfs_emit(buf, "%s\n", is_msix ? "msix" : "msi"); 509 } 510 511 static void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) 512 { 513 struct device_attribute *attrs = desc->sysfs_attrs; 514 int i; 515 516 if (!attrs) 517 return; 518 519 desc->sysfs_attrs = NULL; 520 for (i = 0; i < desc->nvec_used; i++) { 521 if (attrs[i].show) 522 sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name); 523 kfree(attrs[i].attr.name); 524 } 525 kfree(attrs); 526 } 527 528 static int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) 529 { 530 struct device_attribute *attrs; 531 int ret, i; 532 533 attrs = kcalloc(desc->nvec_used, sizeof(*attrs), GFP_KERNEL); 534 if (!attrs) 535 return -ENOMEM; 536 537 desc->sysfs_attrs = attrs; 538 for (i = 0; i < desc->nvec_used; i++) { 539 sysfs_attr_init(&attrs[i].attr); 540 attrs[i].attr.name = kasprintf(GFP_KERNEL, "%d", desc->irq + i); 541 if (!attrs[i].attr.name) { 542 ret = -ENOMEM; 543 goto fail; 544 } 545 546 attrs[i].attr.mode = 0444; 547 attrs[i].show = msi_mode_show; 548 549 ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name); 550 if (ret) { 551 attrs[i].show = NULL; 552 goto fail; 553 } 554 } 555 return 0; 556 557 fail: 558 msi_sysfs_remove_desc(dev, desc); 559 return ret; 560 } 561 562 #if defined(CONFIG_PCI_MSI_ARCH_FALLBACKS) || defined(CONFIG_PCI_XEN) 563 /** 564 * msi_device_populate_sysfs - Populate msi_irqs sysfs entries for a device 565 * @dev: The device (PCI, platform etc) which will get sysfs entries 566 */ 567 int msi_device_populate_sysfs(struct device *dev) 568 { 569 struct msi_desc *desc; 570 int ret; 571 572 msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) { 573 if (desc->sysfs_attrs) 574 continue; 575 ret = msi_sysfs_populate_desc(dev, desc); 576 if (ret) 577 return ret; 578 } 579 return 0; 580 } 581 582 /** 583 * msi_device_destroy_sysfs - Destroy msi_irqs sysfs entries for a device 584 * @dev: The device (PCI, platform etc) for which to remove 585 * sysfs entries 586 */ 587 void msi_device_destroy_sysfs(struct device *dev) 588 { 589 struct msi_desc *desc; 590 591 msi_for_each_desc(desc, dev, MSI_DESC_ALL) 592 msi_sysfs_remove_desc(dev, desc); 593 } 594 #endif /* CONFIG_PCI_MSI_ARCH_FALLBACK || CONFIG_PCI_XEN */ 595 #else /* CONFIG_SYSFS */ 596 static inline int msi_sysfs_create_group(struct device *dev) { return 0; } 597 static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; } 598 static inline void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) { } 599 #endif /* !CONFIG_SYSFS */ 600 601 static struct irq_domain *msi_get_device_domain(struct device *dev, unsigned int domid) 602 { 603 struct irq_domain *domain; 604 605 lockdep_assert_held(&dev->msi.data->mutex); 606 607 if (WARN_ON_ONCE(domid >= MSI_MAX_DEVICE_IRQDOMAINS)) 608 return NULL; 609 610 domain = dev->msi.data->__domains[domid].domain; 611 if (!domain) 612 return NULL; 613 614 if (WARN_ON_ONCE(irq_domain_is_msi_parent(domain))) 615 return NULL; 616 617 return domain; 618 } 619 620 static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid) 621 { 622 struct msi_domain_info *info; 623 struct irq_domain *domain; 624 625 domain = msi_get_device_domain(dev, domid); 626 if (domain) { 627 info = domain->host_data; 628 return info->hwsize; 629 } 630 /* No domain, default to MSI_XA_DOMAIN_SIZE */ 631 return MSI_XA_DOMAIN_SIZE; 632 } 633 634 static inline void irq_chip_write_msi_msg(struct irq_data *data, 635 struct msi_msg *msg) 636 { 637 data->chip->irq_write_msi_msg(data, msg); 638 } 639 640 static void msi_check_level(struct irq_domain *domain, struct msi_msg *msg) 641 { 642 struct msi_domain_info *info = domain->host_data; 643 644 /* 645 * If the MSI provider has messed with the second message and 646 * not advertized that it is level-capable, signal the breakage. 647 */ 648 WARN_ON(!((info->flags & MSI_FLAG_LEVEL_CAPABLE) && 649 (info->chip->flags & IRQCHIP_SUPPORTS_LEVEL_MSI)) && 650 (msg[1].address_lo || msg[1].address_hi || msg[1].data)); 651 } 652 653 /** 654 * msi_domain_set_affinity - Generic affinity setter function for MSI domains 655 * @irq_data: The irq data associated to the interrupt 656 * @mask: The affinity mask to set 657 * @force: Flag to enforce setting (disable online checks) 658 * 659 * Intended to be used by MSI interrupt controllers which are 660 * implemented with hierarchical domains. 661 * 662 * Return: IRQ_SET_MASK_* result code 663 */ 664 int msi_domain_set_affinity(struct irq_data *irq_data, 665 const struct cpumask *mask, bool force) 666 { 667 struct irq_data *parent = irq_data->parent_data; 668 struct msi_msg msg[2] = { [1] = { }, }; 669 int ret; 670 671 ret = parent->chip->irq_set_affinity(parent, mask, force); 672 if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) { 673 BUG_ON(irq_chip_compose_msi_msg(irq_data, msg)); 674 msi_check_level(irq_data->domain, msg); 675 irq_chip_write_msi_msg(irq_data, msg); 676 } 677 678 return ret; 679 } 680 681 static int msi_domain_activate(struct irq_domain *domain, 682 struct irq_data *irq_data, bool early) 683 { 684 struct msi_msg msg[2] = { [1] = { }, }; 685 686 BUG_ON(irq_chip_compose_msi_msg(irq_data, msg)); 687 msi_check_level(irq_data->domain, msg); 688 irq_chip_write_msi_msg(irq_data, msg); 689 return 0; 690 } 691 692 static void msi_domain_deactivate(struct irq_domain *domain, 693 struct irq_data *irq_data) 694 { 695 struct msi_msg msg[2]; 696 697 memset(msg, 0, sizeof(msg)); 698 irq_chip_write_msi_msg(irq_data, msg); 699 } 700 701 static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq, 702 unsigned int nr_irqs, void *arg) 703 { 704 struct msi_domain_info *info = domain->host_data; 705 struct msi_domain_ops *ops = info->ops; 706 irq_hw_number_t hwirq = ops->get_hwirq(info, arg); 707 int i, ret; 708 709 if (irq_find_mapping(domain, hwirq) > 0) 710 return -EEXIST; 711 712 if (domain->parent) { 713 ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg); 714 if (ret < 0) 715 return ret; 716 } 717 718 for (i = 0; i < nr_irqs; i++) { 719 ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg); 720 if (ret < 0) { 721 if (ops->msi_free) { 722 for (i--; i >= 0; i--) 723 ops->msi_free(domain, info, virq + i); 724 } 725 irq_domain_free_irqs_top(domain, virq, nr_irqs); 726 return ret; 727 } 728 } 729 730 return 0; 731 } 732 733 static void msi_domain_free(struct irq_domain *domain, unsigned int virq, 734 unsigned int nr_irqs) 735 { 736 struct msi_domain_info *info = domain->host_data; 737 int i; 738 739 if (info->ops->msi_free) { 740 for (i = 0; i < nr_irqs; i++) 741 info->ops->msi_free(domain, info, virq + i); 742 } 743 irq_domain_free_irqs_top(domain, virq, nr_irqs); 744 } 745 746 static int msi_domain_translate(struct irq_domain *domain, struct irq_fwspec *fwspec, 747 irq_hw_number_t *hwirq, unsigned int *type) 748 { 749 struct msi_domain_info *info = domain->host_data; 750 751 /* 752 * This will catch allocations through the regular irqdomain path except 753 * for MSI domains which really support this, e.g. MBIGEN. 754 */ 755 if (!info->ops->msi_translate) 756 return -ENOTSUPP; 757 return info->ops->msi_translate(domain, fwspec, hwirq, type); 758 } 759 760 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS 761 static void msi_domain_debug_show(struct seq_file *m, struct irq_domain *d, 762 struct irq_data *irqd, int ind) 763 { 764 struct msi_desc *desc = irqd ? irq_data_get_msi_desc(irqd) : NULL; 765 766 if (!desc) 767 return; 768 769 seq_printf(m, "\n%*saddress_hi: 0x%08x", ind + 1, "", desc->msg.address_hi); 770 seq_printf(m, "\n%*saddress_lo: 0x%08x", ind + 1, "", desc->msg.address_lo); 771 seq_printf(m, "\n%*smsg_data: 0x%08x\n", ind + 1, "", desc->msg.data); 772 } 773 #endif 774 775 static const struct irq_domain_ops msi_domain_ops = { 776 .alloc = msi_domain_alloc, 777 .free = msi_domain_free, 778 .activate = msi_domain_activate, 779 .deactivate = msi_domain_deactivate, 780 .translate = msi_domain_translate, 781 #ifdef CONFIG_GENERIC_IRQ_DEBUGFS 782 .debug_show = msi_domain_debug_show, 783 #endif 784 }; 785 786 static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info, 787 msi_alloc_info_t *arg) 788 { 789 return arg->hwirq; 790 } 791 792 static int msi_domain_ops_prepare(struct irq_domain *domain, struct device *dev, 793 int nvec, msi_alloc_info_t *arg) 794 { 795 memset(arg, 0, sizeof(*arg)); 796 return 0; 797 } 798 799 static void msi_domain_ops_teardown(struct irq_domain *domain, msi_alloc_info_t *arg) 800 { 801 } 802 803 static void msi_domain_ops_set_desc(msi_alloc_info_t *arg, 804 struct msi_desc *desc) 805 { 806 arg->desc = desc; 807 } 808 809 static int msi_domain_ops_init(struct irq_domain *domain, 810 struct msi_domain_info *info, 811 unsigned int virq, irq_hw_number_t hwirq, 812 msi_alloc_info_t *arg) 813 { 814 irq_domain_set_hwirq_and_chip(domain, virq, hwirq, info->chip, 815 info->chip_data); 816 if (info->handler && info->handler_name) { 817 __irq_set_handler(virq, info->handler, 0, info->handler_name); 818 if (info->handler_data) 819 irq_set_handler_data(virq, info->handler_data); 820 } 821 return 0; 822 } 823 824 static struct msi_domain_ops msi_domain_ops_default = { 825 .get_hwirq = msi_domain_ops_get_hwirq, 826 .msi_init = msi_domain_ops_init, 827 .msi_prepare = msi_domain_ops_prepare, 828 .msi_teardown = msi_domain_ops_teardown, 829 .set_desc = msi_domain_ops_set_desc, 830 }; 831 832 static void msi_domain_update_dom_ops(struct msi_domain_info *info) 833 { 834 struct msi_domain_ops *ops = info->ops; 835 836 if (ops == NULL) { 837 info->ops = &msi_domain_ops_default; 838 return; 839 } 840 841 if (!(info->flags & MSI_FLAG_USE_DEF_DOM_OPS)) 842 return; 843 844 if (ops->get_hwirq == NULL) 845 ops->get_hwirq = msi_domain_ops_default.get_hwirq; 846 if (ops->msi_init == NULL) 847 ops->msi_init = msi_domain_ops_default.msi_init; 848 if (ops->msi_prepare == NULL) 849 ops->msi_prepare = msi_domain_ops_default.msi_prepare; 850 if (ops->msi_teardown == NULL) 851 ops->msi_teardown = msi_domain_ops_default.msi_teardown; 852 if (ops->set_desc == NULL) 853 ops->set_desc = msi_domain_ops_default.set_desc; 854 } 855 856 static void msi_domain_update_chip_ops(struct msi_domain_info *info) 857 { 858 struct irq_chip *chip = info->chip; 859 860 BUG_ON(!chip || !chip->irq_mask || !chip->irq_unmask); 861 if (!chip->irq_set_affinity && !(info->flags & MSI_FLAG_NO_AFFINITY)) 862 chip->irq_set_affinity = msi_domain_set_affinity; 863 } 864 865 static struct irq_domain *__msi_create_irq_domain(struct fwnode_handle *fwnode, 866 struct msi_domain_info *info, 867 unsigned int flags, 868 struct irq_domain *parent) 869 { 870 struct irq_domain *domain; 871 872 if (info->hwsize > MSI_XA_DOMAIN_SIZE) 873 return NULL; 874 875 /* 876 * Hardware size 0 is valid for backwards compatibility and for 877 * domains which are not backed by a hardware table. Grant the 878 * maximum index space. 879 */ 880 if (!info->hwsize) 881 info->hwsize = MSI_XA_DOMAIN_SIZE; 882 883 msi_domain_update_dom_ops(info); 884 if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) 885 msi_domain_update_chip_ops(info); 886 887 domain = irq_domain_create_hierarchy(parent, flags | IRQ_DOMAIN_FLAG_MSI, 0, 888 fwnode, &msi_domain_ops, info); 889 890 if (domain) { 891 irq_domain_update_bus_token(domain, info->bus_token); 892 domain->dev = info->dev; 893 if (info->flags & MSI_FLAG_PARENT_PM_DEV) 894 domain->pm_dev = parent->pm_dev; 895 } 896 897 return domain; 898 } 899 900 /** 901 * msi_create_irq_domain - Create an MSI interrupt domain 902 * @fwnode: Optional fwnode of the interrupt controller 903 * @info: MSI domain info 904 * @parent: Parent irq domain 905 * 906 * Return: pointer to the created &struct irq_domain or %NULL on failure 907 */ 908 struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, 909 struct msi_domain_info *info, 910 struct irq_domain *parent) 911 { 912 return __msi_create_irq_domain(fwnode, info, 0, parent); 913 } 914 915 /** 916 * msi_create_parent_irq_domain - Create an MSI-parent interrupt domain 917 * @info: MSI irqdomain creation info 918 * @msi_parent_ops: MSI parent callbacks and configuration 919 * 920 * Return: pointer to the created &struct irq_domain or %NULL on failure 921 */ 922 struct irq_domain *msi_create_parent_irq_domain(struct irq_domain_info *info, 923 const struct msi_parent_ops *msi_parent_ops) 924 { 925 struct irq_domain *d; 926 927 info->hwirq_max = max(info->hwirq_max, info->size); 928 info->size = info->hwirq_max; 929 info->domain_flags |= IRQ_DOMAIN_FLAG_MSI_PARENT; 930 info->bus_token = msi_parent_ops->bus_select_token; 931 932 d = irq_domain_instantiate(info); 933 if (IS_ERR(d)) 934 return NULL; 935 936 d->msi_parent_ops = msi_parent_ops; 937 return d; 938 } 939 EXPORT_SYMBOL_GPL(msi_create_parent_irq_domain); 940 941 /** 942 * msi_parent_init_dev_msi_info - Delegate initialization of device MSI info down 943 * in the domain hierarchy 944 * @dev: The device for which the domain should be created 945 * @domain: The domain in the hierarchy this op is being called on 946 * @msi_parent_domain: The IRQ_DOMAIN_FLAG_MSI_PARENT domain for the child to 947 * be created 948 * @msi_child_info: The MSI domain info of the IRQ_DOMAIN_FLAG_MSI_DEVICE 949 * domain to be created 950 * 951 * Return: true on success, false otherwise 952 * 953 * This is the most complex problem of per device MSI domains and the 954 * underlying interrupt domain hierarchy: 955 * 956 * The device domain to be initialized requests the broadest feature set 957 * possible and the underlying domain hierarchy puts restrictions on it. 958 * 959 * That's trivial for a simple parent->child relationship, but it gets 960 * interesting with an intermediate domain: root->parent->child. The 961 * intermediate 'parent' can expand the capabilities which the 'root' 962 * domain is providing. So that creates a classic hen and egg problem: 963 * Which entity is doing the restrictions/expansions? 964 * 965 * One solution is to let the root domain handle the initialization that's 966 * why there is the @domain and the @msi_parent_domain pointer. 967 */ 968 bool msi_parent_init_dev_msi_info(struct device *dev, struct irq_domain *domain, 969 struct irq_domain *msi_parent_domain, 970 struct msi_domain_info *msi_child_info) 971 { 972 struct irq_domain *parent = domain->parent; 973 974 if (WARN_ON_ONCE(!parent || !parent->msi_parent_ops || 975 !parent->msi_parent_ops->init_dev_msi_info)) 976 return false; 977 978 return parent->msi_parent_ops->init_dev_msi_info(dev, parent, msi_parent_domain, 979 msi_child_info); 980 } 981 982 /** 983 * msi_create_device_irq_domain - Create a device MSI interrupt domain 984 * @dev: Pointer to the device 985 * @domid: Domain id 986 * @template: MSI domain info bundle used as template 987 * @hwsize: Maximum number of MSI table entries (0 if unknown or unlimited) 988 * @domain_data: Optional pointer to domain specific data which is set in 989 * msi_domain_info::data 990 * @chip_data: Optional pointer to chip specific data which is set in 991 * msi_domain_info::chip_data 992 * 993 * Return: True on success, false otherwise 994 * 995 * There is no firmware node required for this interface because the per 996 * device domains are software constructs which are actually closer to the 997 * hardware reality than any firmware can describe them. 998 * 999 * The domain name and the irq chip name for a MSI device domain are 1000 * composed by: "$(PREFIX)$(CHIPNAME)-$(DEVNAME)" 1001 * 1002 * $PREFIX: Optional prefix provided by the underlying MSI parent domain 1003 * via msi_parent_ops::prefix. If that pointer is NULL the prefix 1004 * is empty. 1005 * $CHIPNAME: The name of the irq_chip in @template 1006 * $DEVNAME: The name of the device 1007 * 1008 * This results in understandable chip names and hardware interrupt numbers 1009 * in e.g. /proc/interrupts 1010 * 1011 * PCI-MSI-0000:00:1c.0 0-edge Parent domain has no prefix 1012 * IR-PCI-MSI-0000:00:1c.4 0-edge Same with interrupt remapping prefix 'IR-' 1013 * 1014 * IR-PCI-MSIX-0000:3d:00.0 0-edge Hardware interrupt numbers reflect 1015 * IR-PCI-MSIX-0000:3d:00.0 1-edge the real MSI-X index on that device 1016 * IR-PCI-MSIX-0000:3d:00.0 2-edge 1017 * 1018 * On IMS domains the hardware interrupt number is either a table entry 1019 * index or a purely software managed index but it is guaranteed to be 1020 * unique. 1021 * 1022 * The domain pointer is stored in @dev::msi::data::__irqdomains[]. All 1023 * subsequent operations on the domain depend on the domain id. 1024 * 1025 * The domain is automatically freed when the device is removed via devres 1026 * in the context of @dev::msi::data freeing, but it can also be 1027 * independently removed via @msi_remove_device_irq_domain(). 1028 */ 1029 bool msi_create_device_irq_domain(struct device *dev, unsigned int domid, 1030 const struct msi_domain_template *template, 1031 unsigned int hwsize, void *domain_data, 1032 void *chip_data) 1033 { 1034 struct irq_domain *domain, *parent = dev->msi.domain; 1035 const struct msi_parent_ops *pops; 1036 struct fwnode_handle *fwnode; 1037 1038 if (!irq_domain_is_msi_parent(parent)) 1039 return false; 1040 1041 if (domid >= MSI_MAX_DEVICE_IRQDOMAINS) 1042 return false; 1043 1044 struct msi_domain_template *bundle __free(kfree) = 1045 kmemdup(template, sizeof(*bundle), GFP_KERNEL); 1046 if (!bundle) 1047 return false; 1048 1049 bundle->info.hwsize = hwsize; 1050 bundle->info.chip = &bundle->chip; 1051 bundle->info.ops = &bundle->ops; 1052 bundle->info.data = domain_data; 1053 bundle->info.chip_data = chip_data; 1054 bundle->info.alloc_data = &bundle->alloc_info; 1055 bundle->info.dev = dev; 1056 1057 pops = parent->msi_parent_ops; 1058 snprintf(bundle->name, sizeof(bundle->name), "%s%s-%s", 1059 pops->prefix ? : "", bundle->chip.name, dev_name(dev)); 1060 bundle->chip.name = bundle->name; 1061 1062 /* 1063 * Using the device firmware node is required for wire to MSI 1064 * device domains so that the existing firmware results in a domain 1065 * match. 1066 * All other device domains like PCI/MSI use the named firmware 1067 * node as they are not guaranteed to have a fwnode. They are never 1068 * looked up and always handled in the context of the device. 1069 */ 1070 struct fwnode_handle *fwnode_alloced __free(irq_domain_free_fwnode) = NULL; 1071 1072 if (!(bundle->info.flags & MSI_FLAG_USE_DEV_FWNODE)) 1073 fwnode = fwnode_alloced = irq_domain_alloc_named_fwnode(bundle->name); 1074 else 1075 fwnode = dev->fwnode; 1076 1077 if (!fwnode) 1078 return false; 1079 1080 if (msi_setup_device_data(dev)) 1081 return false; 1082 1083 guard(msi_descs_lock)(dev); 1084 if (WARN_ON_ONCE(msi_get_device_domain(dev, domid))) 1085 return false; 1086 1087 if (!pops->init_dev_msi_info(dev, parent, parent, &bundle->info)) 1088 return false; 1089 1090 domain = __msi_create_irq_domain(fwnode, &bundle->info, IRQ_DOMAIN_FLAG_MSI_DEVICE, parent); 1091 if (!domain) 1092 return false; 1093 1094 dev->msi.data->__domains[domid].domain = domain; 1095 1096 if (msi_domain_prepare_irqs(domain, dev, hwsize, &bundle->alloc_info)) { 1097 dev->msi.data->__domains[domid].domain = NULL; 1098 irq_domain_remove(domain); 1099 return false; 1100 } 1101 1102 /* @bundle and @fwnode_alloced are now in use. Prevent cleanup */ 1103 retain_and_null_ptr(bundle); 1104 retain_and_null_ptr(fwnode_alloced); 1105 return true; 1106 } 1107 1108 /** 1109 * msi_remove_device_irq_domain - Free a device MSI interrupt domain 1110 * @dev: Pointer to the device 1111 * @domid: Domain id 1112 */ 1113 void msi_remove_device_irq_domain(struct device *dev, unsigned int domid) 1114 { 1115 struct fwnode_handle *fwnode = NULL; 1116 struct msi_domain_info *info; 1117 struct irq_domain *domain; 1118 1119 guard(msi_descs_lock)(dev); 1120 domain = msi_get_device_domain(dev, domid); 1121 if (!domain || !irq_domain_is_msi_device(domain)) 1122 return; 1123 1124 dev->msi.data->__domains[domid].domain = NULL; 1125 info = domain->host_data; 1126 1127 info->ops->msi_teardown(domain, info->alloc_data); 1128 1129 if (irq_domain_is_msi_device(domain)) 1130 fwnode = domain->fwnode; 1131 irq_domain_remove(domain); 1132 irq_domain_free_fwnode(fwnode); 1133 kfree(container_of(info, struct msi_domain_template, info)); 1134 } 1135 1136 /** 1137 * msi_match_device_irq_domain - Match a device irq domain against a bus token 1138 * @dev: Pointer to the device 1139 * @domid: Domain id 1140 * @bus_token: Bus token to match against the domain bus token 1141 * 1142 * Return: True if device domain exists and bus tokens match. 1143 */ 1144 bool msi_match_device_irq_domain(struct device *dev, unsigned int domid, 1145 enum irq_domain_bus_token bus_token) 1146 { 1147 struct msi_domain_info *info; 1148 struct irq_domain *domain; 1149 1150 guard(msi_descs_lock)(dev); 1151 domain = msi_get_device_domain(dev, domid); 1152 if (domain && irq_domain_is_msi_device(domain)) { 1153 info = domain->host_data; 1154 return info->bus_token == bus_token; 1155 } 1156 return false; 1157 } 1158 1159 static int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev, 1160 int nvec, msi_alloc_info_t *arg) 1161 { 1162 struct msi_domain_info *info = domain->host_data; 1163 struct msi_domain_ops *ops = info->ops; 1164 1165 return ops->msi_prepare(domain, dev, nvec, arg); 1166 } 1167 1168 /* 1169 * Carefully check whether the device can use reservation mode. If 1170 * reservation mode is enabled then the early activation will assign a 1171 * dummy vector to the device. If the PCI/MSI device does not support 1172 * masking of the entry then this can result in spurious interrupts when 1173 * the device driver is not absolutely careful. But even then a malfunction 1174 * of the hardware could result in a spurious interrupt on the dummy vector 1175 * and render the device unusable. If the entry can be masked then the core 1176 * logic will prevent the spurious interrupt and reservation mode can be 1177 * used. For now reservation mode is restricted to PCI/MSI. 1178 */ 1179 static bool msi_check_reservation_mode(struct irq_domain *domain, 1180 struct msi_domain_info *info, 1181 struct device *dev) 1182 { 1183 struct msi_desc *desc; 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 break; 1191 default: 1192 return false; 1193 } 1194 1195 if (!(info->flags & MSI_FLAG_MUST_REACTIVATE)) 1196 return false; 1197 1198 if (info->flags & MSI_FLAG_NO_MASK) 1199 return false; 1200 1201 /* 1202 * Checking the first MSI descriptor is sufficient. MSIX supports 1203 * masking and MSI does so when the can_mask attribute is set. 1204 */ 1205 desc = msi_first_desc(dev, MSI_DESC_ALL); 1206 return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask; 1207 } 1208 1209 static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc, 1210 int allocated) 1211 { 1212 switch(domain->bus_token) { 1213 case DOMAIN_BUS_PCI_MSI: 1214 case DOMAIN_BUS_PCI_DEVICE_MSI: 1215 case DOMAIN_BUS_PCI_DEVICE_MSIX: 1216 case DOMAIN_BUS_VMD_MSI: 1217 if (IS_ENABLED(CONFIG_PCI_MSI)) 1218 break; 1219 fallthrough; 1220 default: 1221 return -ENOSPC; 1222 } 1223 1224 /* Let a failed PCI multi MSI allocation retry */ 1225 if (desc->nvec_used > 1) 1226 return 1; 1227 1228 /* If there was a successful allocation let the caller know */ 1229 return allocated ? allocated : -ENOSPC; 1230 } 1231 1232 #define VIRQ_CAN_RESERVE 0x01 1233 #define VIRQ_ACTIVATE 0x02 1234 1235 static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflags) 1236 { 1237 struct irq_data *irqd = irq_domain_get_irq_data(domain, virq); 1238 int ret; 1239 1240 if (!(vflags & VIRQ_CAN_RESERVE)) { 1241 irqd_clr_can_reserve(irqd); 1242 1243 /* 1244 * If the interrupt is managed but no CPU is available to 1245 * service it, shut it down until better times. Note that 1246 * we only do this on the !RESERVE path as x86 (the only 1247 * architecture using this flag) deals with this in a 1248 * different way by using a catch-all vector. 1249 */ 1250 if ((vflags & VIRQ_ACTIVATE) && 1251 irqd_affinity_is_managed(irqd) && 1252 !cpumask_intersects(irq_data_get_affinity_mask(irqd), 1253 cpu_online_mask)) { 1254 irqd_set_managed_shutdown(irqd); 1255 return 0; 1256 } 1257 } 1258 1259 if (!(vflags & VIRQ_ACTIVATE)) 1260 return 0; 1261 1262 ret = irq_domain_activate_irq(irqd, vflags & VIRQ_CAN_RESERVE); 1263 if (ret) 1264 return ret; 1265 /* 1266 * If the interrupt uses reservation mode, clear the activated bit 1267 * so request_irq() will assign the final vector. 1268 */ 1269 if (vflags & VIRQ_CAN_RESERVE) 1270 irqd_clr_activated(irqd); 1271 return 0; 1272 } 1273 1274 static int populate_alloc_info(struct irq_domain *domain, struct device *dev, 1275 unsigned int nirqs, msi_alloc_info_t *arg) 1276 { 1277 struct msi_domain_info *info = domain->host_data; 1278 1279 /* 1280 * If the caller has provided a template alloc info, use that. Once 1281 * all users of msi_create_irq_domain() have been eliminated, this 1282 * should be the only source of allocation information, and the 1283 * prepare call below should be finally removed. 1284 */ 1285 if (!info->alloc_data) 1286 return msi_domain_prepare_irqs(domain, dev, nirqs, arg); 1287 1288 *arg = *info->alloc_data; 1289 return 0; 1290 } 1291 1292 static int __msi_domain_alloc_irqs(struct device *dev, struct irq_domain *domain, 1293 struct msi_ctrl *ctrl) 1294 { 1295 struct xarray *xa = &dev->msi.data->__domains[ctrl->domid].store; 1296 struct msi_domain_info *info = domain->host_data; 1297 struct msi_domain_ops *ops = info->ops; 1298 unsigned int vflags = 0, allocated = 0; 1299 msi_alloc_info_t arg = { }; 1300 struct msi_desc *desc; 1301 unsigned long idx; 1302 int i, ret, virq; 1303 1304 ret = populate_alloc_info(domain, dev, ctrl->nirqs, &arg); 1305 if (ret) 1306 return ret; 1307 1308 /* 1309 * This flag is set by the PCI layer as we need to activate 1310 * the MSI entries before the PCI layer enables MSI in the 1311 * card. Otherwise the card latches a random msi message. 1312 */ 1313 if (info->flags & MSI_FLAG_ACTIVATE_EARLY) 1314 vflags |= VIRQ_ACTIVATE; 1315 1316 /* 1317 * Interrupt can use a reserved vector and will not occupy 1318 * a real device vector until the interrupt is requested. 1319 */ 1320 if (msi_check_reservation_mode(domain, info, dev)) 1321 vflags |= VIRQ_CAN_RESERVE; 1322 1323 xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) { 1324 if (!msi_desc_match(desc, MSI_DESC_NOTASSOCIATED)) 1325 continue; 1326 1327 /* This should return -ECONFUSED... */ 1328 if (WARN_ON_ONCE(allocated >= ctrl->nirqs)) 1329 return -EINVAL; 1330 1331 if (ops->prepare_desc) 1332 ops->prepare_desc(domain, &arg, desc); 1333 1334 ops->set_desc(&arg, desc); 1335 1336 virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used, 1337 dev_to_node(dev), &arg, false, 1338 desc->affinity); 1339 if (virq < 0) 1340 return msi_handle_pci_fail(domain, desc, allocated); 1341 1342 for (i = 0; i < desc->nvec_used; i++) { 1343 irq_set_msi_desc_off(virq, i, desc); 1344 irq_debugfs_copy_devname(virq + i, dev); 1345 ret = msi_init_virq(domain, virq + i, vflags); 1346 if (ret) 1347 return ret; 1348 } 1349 if (info->flags & MSI_FLAG_DEV_SYSFS) { 1350 ret = msi_sysfs_populate_desc(dev, desc); 1351 if (ret) 1352 return ret; 1353 } 1354 allocated++; 1355 } 1356 return 0; 1357 } 1358 1359 static int msi_domain_alloc_simple_msi_descs(struct device *dev, 1360 struct msi_domain_info *info, 1361 struct msi_ctrl *ctrl) 1362 { 1363 if (!(info->flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS)) 1364 return 0; 1365 1366 return msi_domain_add_simple_msi_descs(dev, ctrl); 1367 } 1368 1369 static int __msi_domain_alloc_locked(struct device *dev, struct msi_ctrl *ctrl) 1370 { 1371 struct msi_domain_info *info; 1372 struct msi_domain_ops *ops; 1373 struct irq_domain *domain; 1374 int ret; 1375 1376 if (!msi_ctrl_valid(dev, ctrl)) 1377 return -EINVAL; 1378 1379 domain = msi_get_device_domain(dev, ctrl->domid); 1380 if (!domain) 1381 return -ENODEV; 1382 1383 info = domain->host_data; 1384 1385 ret = msi_domain_alloc_simple_msi_descs(dev, info, ctrl); 1386 if (ret) 1387 return ret; 1388 1389 ops = info->ops; 1390 if (ops->domain_alloc_irqs) 1391 return ops->domain_alloc_irqs(domain, dev, ctrl->nirqs); 1392 1393 return __msi_domain_alloc_irqs(dev, domain, ctrl); 1394 } 1395 1396 static int msi_domain_alloc_locked(struct device *dev, struct msi_ctrl *ctrl) 1397 { 1398 int ret = __msi_domain_alloc_locked(dev, ctrl); 1399 1400 if (ret) 1401 msi_domain_free_locked(dev, ctrl); 1402 return ret; 1403 } 1404 1405 /** 1406 * msi_domain_alloc_irqs_range_locked - Allocate interrupts from a MSI interrupt domain 1407 * @dev: Pointer to device struct of the device for which the interrupts 1408 * are allocated 1409 * @domid: Id of the interrupt domain to operate on 1410 * @first: First index to allocate (inclusive) 1411 * @last: Last index to allocate (inclusive) 1412 * 1413 * Must be invoked from within a msi_lock_descs() / msi_unlock_descs() 1414 * pair. Use this for MSI irqdomains which implement their own descriptor 1415 * allocation/free. 1416 * 1417 * Return: %0 on success or an error code. 1418 */ 1419 int msi_domain_alloc_irqs_range_locked(struct device *dev, unsigned int domid, 1420 unsigned int first, unsigned int last) 1421 { 1422 struct msi_ctrl ctrl = { 1423 .domid = domid, 1424 .first = first, 1425 .last = last, 1426 .nirqs = last + 1 - first, 1427 }; 1428 1429 return msi_domain_alloc_locked(dev, &ctrl); 1430 } 1431 1432 /** 1433 * msi_domain_alloc_irqs_range - Allocate interrupts from a MSI interrupt domain 1434 * @dev: Pointer to device struct of the device for which the interrupts 1435 * are allocated 1436 * @domid: Id of the interrupt domain to operate on 1437 * @first: First index to allocate (inclusive) 1438 * @last: Last index to allocate (inclusive) 1439 * 1440 * Return: %0 on success or an error code. 1441 */ 1442 int msi_domain_alloc_irqs_range(struct device *dev, unsigned int domid, 1443 unsigned int first, unsigned int last) 1444 { 1445 1446 guard(msi_descs_lock)(dev); 1447 return msi_domain_alloc_irqs_range_locked(dev, domid, first, last); 1448 } 1449 EXPORT_SYMBOL_GPL(msi_domain_alloc_irqs_range); 1450 1451 /** 1452 * msi_domain_alloc_irqs_all_locked - Allocate all interrupts from a MSI interrupt domain 1453 * 1454 * @dev: Pointer to device struct of the device for which the interrupts 1455 * are allocated 1456 * @domid: Id of the interrupt domain to operate on 1457 * @nirqs: The number of interrupts to allocate 1458 * 1459 * This function scans all MSI descriptors of the MSI domain and allocates interrupts 1460 * for all unassigned ones. That function is to be used for MSI domain usage where 1461 * the descriptor allocation is handled at the call site, e.g. PCI/MSI[X]. 1462 * 1463 * Return: %0 on success or an error code. 1464 */ 1465 int msi_domain_alloc_irqs_all_locked(struct device *dev, unsigned int domid, int nirqs) 1466 { 1467 struct msi_ctrl ctrl = { 1468 .domid = domid, 1469 .first = 0, 1470 .last = msi_domain_get_hwsize(dev, domid) - 1, 1471 .nirqs = nirqs, 1472 }; 1473 1474 return msi_domain_alloc_locked(dev, &ctrl); 1475 } 1476 1477 static struct msi_map __msi_domain_alloc_irq_at(struct device *dev, unsigned int domid, 1478 unsigned int index, 1479 const struct irq_affinity_desc *affdesc, 1480 union msi_instance_cookie *icookie) 1481 { 1482 struct msi_ctrl ctrl = { .domid = domid, .nirqs = 1, }; 1483 struct irq_domain *domain; 1484 struct msi_map map = { }; 1485 struct msi_desc *desc; 1486 int ret; 1487 1488 domain = msi_get_device_domain(dev, domid); 1489 if (!domain) { 1490 map.index = -ENODEV; 1491 return map; 1492 } 1493 1494 desc = msi_alloc_desc(dev, 1, affdesc); 1495 if (!desc) { 1496 map.index = -ENOMEM; 1497 return map; 1498 } 1499 1500 if (icookie) 1501 desc->data.icookie = *icookie; 1502 1503 ret = msi_insert_desc(dev, desc, domid, index); 1504 if (ret) { 1505 map.index = ret; 1506 return map; 1507 } 1508 1509 ctrl.first = ctrl.last = desc->msi_index; 1510 1511 ret = __msi_domain_alloc_irqs(dev, domain, &ctrl); 1512 if (ret) { 1513 map.index = ret; 1514 msi_domain_free_locked(dev, &ctrl); 1515 } else { 1516 map.index = desc->msi_index; 1517 map.virq = desc->irq; 1518 } 1519 return map; 1520 } 1521 1522 /** 1523 * msi_domain_alloc_irq_at - Allocate an interrupt from a MSI interrupt domain at 1524 * a given index - or at the next free index 1525 * 1526 * @dev: Pointer to device struct of the device for which the interrupts 1527 * are allocated 1528 * @domid: Id of the interrupt domain to operate on 1529 * @index: Index for allocation. If @index == %MSI_ANY_INDEX the allocation 1530 * uses the next free index. 1531 * @affdesc: Optional pointer to an interrupt affinity descriptor structure 1532 * @icookie: Optional pointer to a domain specific per instance cookie. If 1533 * non-NULL the content of the cookie is stored in msi_desc::data. 1534 * Must be NULL for MSI-X allocations 1535 * 1536 * This requires a MSI interrupt domain which lets the core code manage the 1537 * MSI descriptors. 1538 * 1539 * Return: struct msi_map 1540 * 1541 * On success msi_map::index contains the allocated index number and 1542 * msi_map::virq the corresponding Linux interrupt number 1543 * 1544 * On failure msi_map::index contains the error code and msi_map::virq 1545 * is %0. 1546 */ 1547 struct msi_map msi_domain_alloc_irq_at(struct device *dev, unsigned int domid, unsigned int index, 1548 const struct irq_affinity_desc *affdesc, 1549 union msi_instance_cookie *icookie) 1550 { 1551 guard(msi_descs_lock)(dev); 1552 return __msi_domain_alloc_irq_at(dev, domid, index, affdesc, icookie); 1553 } 1554 1555 /** 1556 * msi_device_domain_alloc_wired - Allocate a "wired" interrupt on @domain 1557 * @domain: The domain to allocate on 1558 * @hwirq: The hardware interrupt number to allocate for 1559 * @type: The interrupt type 1560 * 1561 * This weirdness supports wire to MSI controllers like MBIGEN. 1562 * 1563 * @hwirq is the hardware interrupt number which is handed in from 1564 * irq_create_fwspec_mapping(). As the wire to MSI domain is sparse, but 1565 * sized in firmware, the hardware interrupt number cannot be used as MSI 1566 * index. For the underlying irq chip the MSI index is irrelevant and 1567 * all it needs is the hardware interrupt number. 1568 * 1569 * To handle this the MSI index is allocated with MSI_ANY_INDEX and the 1570 * hardware interrupt number is stored along with the type information in 1571 * msi_desc::cookie so the underlying interrupt chip and domain code can 1572 * retrieve it. 1573 * 1574 * Return: The Linux interrupt number (> 0) or an error code 1575 */ 1576 int msi_device_domain_alloc_wired(struct irq_domain *domain, unsigned int hwirq, 1577 unsigned int type) 1578 { 1579 unsigned int domid = MSI_DEFAULT_DOMAIN; 1580 union msi_instance_cookie icookie = { }; 1581 struct device *dev = domain->dev; 1582 struct msi_map map = { }; 1583 1584 if (WARN_ON_ONCE(!dev || domain->bus_token != DOMAIN_BUS_WIRED_TO_MSI)) 1585 return -EINVAL; 1586 1587 icookie.value = ((u64)type << 32) | hwirq; 1588 1589 guard(msi_descs_lock)(dev); 1590 if (WARN_ON_ONCE(msi_get_device_domain(dev, domid) != domain)) 1591 map.index = -EINVAL; 1592 else 1593 map = __msi_domain_alloc_irq_at(dev, domid, MSI_ANY_INDEX, NULL, &icookie); 1594 return map.index >= 0 ? map.virq : map.index; 1595 } 1596 1597 static void __msi_domain_free_irqs(struct device *dev, struct irq_domain *domain, 1598 struct msi_ctrl *ctrl) 1599 { 1600 struct xarray *xa = &dev->msi.data->__domains[ctrl->domid].store; 1601 struct msi_domain_info *info = domain->host_data; 1602 struct irq_data *irqd; 1603 struct msi_desc *desc; 1604 unsigned long idx; 1605 int i; 1606 1607 xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) { 1608 /* Only handle MSI entries which have an interrupt associated */ 1609 if (!msi_desc_match(desc, MSI_DESC_ASSOCIATED)) 1610 continue; 1611 1612 /* Make sure all interrupts are deactivated */ 1613 for (i = 0; i < desc->nvec_used; i++) { 1614 irqd = irq_domain_get_irq_data(domain, desc->irq + i); 1615 if (irqd && irqd_is_activated(irqd)) 1616 irq_domain_deactivate_irq(irqd); 1617 } 1618 1619 irq_domain_free_irqs(desc->irq, desc->nvec_used); 1620 if (info->flags & MSI_FLAG_DEV_SYSFS) 1621 msi_sysfs_remove_desc(dev, desc); 1622 desc->irq = 0; 1623 } 1624 } 1625 1626 static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl) 1627 { 1628 struct msi_domain_info *info; 1629 struct msi_domain_ops *ops; 1630 struct irq_domain *domain; 1631 1632 if (!msi_ctrl_valid(dev, ctrl)) 1633 return; 1634 1635 domain = msi_get_device_domain(dev, ctrl->domid); 1636 if (!domain) 1637 return; 1638 1639 info = domain->host_data; 1640 ops = info->ops; 1641 1642 if (ops->domain_free_irqs) 1643 ops->domain_free_irqs(domain, dev); 1644 else 1645 __msi_domain_free_irqs(dev, domain, ctrl); 1646 1647 if (ops->msi_post_free) 1648 ops->msi_post_free(domain, dev); 1649 1650 if (info->flags & MSI_FLAG_FREE_MSI_DESCS) 1651 msi_domain_free_descs(dev, ctrl); 1652 } 1653 1654 /** 1655 * msi_domain_free_irqs_range_locked - Free a range of interrupts from a MSI interrupt domain 1656 * associated to @dev with msi_lock held 1657 * @dev: Pointer to device struct of the device for which the interrupts 1658 * are freed 1659 * @domid: Id of the interrupt domain to operate on 1660 * @first: First index to free (inclusive) 1661 * @last: Last index to free (inclusive) 1662 */ 1663 void msi_domain_free_irqs_range_locked(struct device *dev, unsigned int domid, 1664 unsigned int first, unsigned int last) 1665 { 1666 struct msi_ctrl ctrl = { 1667 .domid = domid, 1668 .first = first, 1669 .last = last, 1670 }; 1671 msi_domain_free_locked(dev, &ctrl); 1672 } 1673 1674 /** 1675 * msi_domain_free_irqs_range - Free a range of interrupts from a MSI interrupt domain 1676 * associated to @dev 1677 * @dev: Pointer to device struct of the device for which the interrupts 1678 * are freed 1679 * @domid: Id of the interrupt domain to operate on 1680 * @first: First index to free (inclusive) 1681 * @last: Last index to free (inclusive) 1682 */ 1683 void msi_domain_free_irqs_range(struct device *dev, unsigned int domid, 1684 unsigned int first, unsigned int last) 1685 { 1686 guard(msi_descs_lock)(dev); 1687 msi_domain_free_irqs_range_locked(dev, domid, first, last); 1688 } 1689 EXPORT_SYMBOL_GPL(msi_domain_free_irqs_all); 1690 1691 /** 1692 * msi_domain_free_irqs_all_locked - Free all interrupts from a MSI interrupt domain 1693 * associated to a device 1694 * @dev: Pointer to device struct of the device for which the interrupts 1695 * are freed 1696 * @domid: The id of the domain to operate on 1697 * 1698 * Must be invoked from within a msi_lock_descs() / msi_unlock_descs() 1699 * pair. Use this for MSI irqdomains which implement their own vector 1700 * allocation. 1701 */ 1702 void msi_domain_free_irqs_all_locked(struct device *dev, unsigned int domid) 1703 { 1704 msi_domain_free_irqs_range_locked(dev, domid, 0, 1705 msi_domain_get_hwsize(dev, domid) - 1); 1706 } 1707 1708 /** 1709 * msi_domain_free_irqs_all - Free all interrupts from a MSI interrupt domain 1710 * associated to a device 1711 * @dev: Pointer to device struct of the device for which the interrupts 1712 * are freed 1713 * @domid: The id of the domain to operate on 1714 */ 1715 void msi_domain_free_irqs_all(struct device *dev, unsigned int domid) 1716 { 1717 guard(msi_descs_lock)(dev); 1718 msi_domain_free_irqs_all_locked(dev, domid); 1719 } 1720 1721 /** 1722 * msi_device_domain_free_wired - Free a wired interrupt in @domain 1723 * @domain: The domain to free the interrupt on 1724 * @virq: The Linux interrupt number to free 1725 * 1726 * This is the counterpart of msi_device_domain_alloc_wired() for the 1727 * weird wired to MSI converting domains. 1728 */ 1729 void msi_device_domain_free_wired(struct irq_domain *domain, unsigned int virq) 1730 { 1731 struct msi_desc *desc = irq_get_msi_desc(virq); 1732 struct device *dev = domain->dev; 1733 1734 if (WARN_ON_ONCE(!dev || !desc || domain->bus_token != DOMAIN_BUS_WIRED_TO_MSI)) 1735 return; 1736 1737 guard(msi_descs_lock)(dev); 1738 if (WARN_ON_ONCE(msi_get_device_domain(dev, MSI_DEFAULT_DOMAIN) != domain)) 1739 return; 1740 msi_domain_free_irqs_range_locked(dev, MSI_DEFAULT_DOMAIN, desc->msi_index, 1741 desc->msi_index); 1742 } 1743 1744 /** 1745 * msi_get_domain_info - Get the MSI interrupt domain info for @domain 1746 * @domain: The interrupt domain to retrieve data from 1747 * 1748 * Return: the pointer to the msi_domain_info stored in @domain->host_data. 1749 */ 1750 struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain) 1751 { 1752 return (struct msi_domain_info *)domain->host_data; 1753 } 1754 1755 /** 1756 * msi_device_has_isolated_msi - True if the device has isolated MSI 1757 * @dev: The device to check 1758 * 1759 * Isolated MSI means that HW modeled by an irq_domain on the path from the 1760 * initiating device to the CPU will validate that the MSI message specifies an 1761 * interrupt number that the device is authorized to trigger. This must block 1762 * devices from triggering interrupts they are not authorized to trigger. 1763 * Currently authorization means the MSI vector is one assigned to the device. 1764 * 1765 * This is interesting for securing VFIO use cases where a rouge MSI (eg created 1766 * by abusing a normal PCI MemWr DMA) must not allow the VFIO userspace to 1767 * impact outside its security domain, eg userspace triggering interrupts on 1768 * kernel drivers, a VM triggering interrupts on the hypervisor, or a VM 1769 * triggering interrupts on another VM. 1770 */ 1771 bool msi_device_has_isolated_msi(struct device *dev) 1772 { 1773 struct irq_domain *domain = dev_get_msi_domain(dev); 1774 1775 for (; domain; domain = domain->parent) 1776 if (domain->flags & IRQ_DOMAIN_FLAG_ISOLATED_MSI) 1777 return true; 1778 return arch_is_isolated_msi(); 1779 } 1780 EXPORT_SYMBOL_GPL(msi_device_has_isolated_msi); 1781