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 */ 30 struct 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 42 static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl); 43 static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid); 44 static 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 */ 58 static 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 78 static void msi_free_desc(struct msi_desc *desc) 79 { 80 kfree(desc->affinity); 81 kfree(desc); 82 } 83 84 static 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 } 117 fail: 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 */ 132 int 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 } 148 149 static 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 } 162 163 static 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 } 179 180 static 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 */ 209 void 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 */ 228 static 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; 248 249 fail_mem: 250 ret = -ENOMEM; 251 fail: 252 msi_domain_free_descs(dev, ctrl); 253 return ret; 254 } 255 256 void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) 257 { 258 *msg = entry->msg; 259 } 260 261 void 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 } 267 EXPORT_SYMBOL_GPL(get_cached_msi_msg); 268 269 static 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 */ 292 int 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 */ 332 void msi_lock_descs(struct device *dev) 333 { 334 mutex_lock(&dev->msi.data->mutex); 335 } 336 EXPORT_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 */ 342 void 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 } 348 EXPORT_SYMBOL_GPL(msi_unlock_descs); 349 350 static 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 */ 376 struct 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 } 389 EXPORT_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 */ 405 struct 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 } 421 EXPORT_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 */ 431 unsigned 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 } 468 EXPORT_SYMBOL_GPL(msi_domain_get_virq); 469 470 #ifdef CONFIG_SYSFS 471 static struct attribute *msi_dev_attrs[] = { 472 NULL 473 }; 474 475 static const struct attribute_group msi_irqs_group = { 476 .name = "msi_irqs", 477 .attrs = msi_dev_attrs, 478 }; 479 480 static inline int msi_sysfs_create_group(struct device *dev) 481 { 482 return devm_device_add_group(dev, &msi_irqs_group); 483 } 484 485 static 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 } 493 494 static 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 } 510 511 static 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; 539 540 fail: 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 */ 550 int 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 */ 570 void 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 */ 579 static inline int msi_sysfs_create_group(struct device *dev) { return 0; } 580 static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; } 581 static inline void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) { } 582 #endif /* !CONFIG_SYSFS */ 583 584 static 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 } 602 603 static 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 } 616 617 static 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 } 622 623 static 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 */ 647 int 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 } 663 664 static 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 } 674 675 static 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 } 683 684 static 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 } 715 716 static 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 } 728 729 static 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 }; 735 736 static 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 } 741 742 static 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 } 748 749 static void msi_domain_ops_set_desc(msi_alloc_info_t *arg, 750 struct msi_desc *desc) 751 { 752 arg->desc = desc; 753 } 754 755 static 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 } 769 770 static 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 }; 776 777 static 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 } 798 799 static 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 } 807 808 static 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 */ 847 struct 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 */ 881 bool 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 */ 942 bool 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; 996 997 fail: 998 msi_unlock_descs(dev); 999 free_fwnode: 1000 irq_domain_free_fwnode(fwnode); 1001 free_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 */ 1011 void 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 1032 unlock: 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 */ 1044 bool 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 1061 int 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 1070 int 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 1111 fail: 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); 1117 unlock: 1118 msi_unlock_descs(dev); 1119 return ret; 1120 } 1121 1122 void 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 */ 1152 static 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 1182 static 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 1208 static 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 1247 static 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 1314 static 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 1324 static 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 1351 static 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 */ 1374 int 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 */ 1397 int 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 */ 1422 int 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 */ 1459 struct 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 } 1501 unlock: 1502 msi_unlock_descs(dev); 1503 return map; 1504 } 1505 1506 static 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 1535 static 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 */ 1572 void 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 */ 1592 void 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 */ 1611 void 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 */ 1624 void 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 */ 1637 struct 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 */ 1658 bool 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 } 1667 EXPORT_SYMBOL_GPL(msi_device_has_isolated_msi); 1668