kernel/irq/irqdesc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
   4  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
   5  *
   6  * This file contains the interrupt descriptor management code. Detailed
   7  * information is available in Documentation/core-api/genericirq.rst
   8  *
   9  */
  10 #include <linux/irq.h>
  11 #include <linux/slab.h>
  12 #include <linux/export.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/kernel_stat.h>
  15 #include <linux/maple_tree.h>
  16 #include <linux/irqdomain.h>
  17 #include <linux/sysfs.h>
  18
  19 #include "internals.h"
  20
  21 /*
  22  * lockdep: we want to handle all irq_desc locks as a single lock-class:
  23  */
  24 static struct lock_class_key irq_desc_lock_class;
  25
  26 #if defined(CONFIG_SMP)
  27 static int __init irq_affinity_setup(char *str)
  28 {
  29         alloc_bootmem_cpumask_var(&irq_default_affinity);
  30         cpulist_parse(str, irq_default_affinity);
  31         /*
  32          * Set at least the boot cpu. We don't want to end up with
  33          * bugreports caused by random commandline masks
  34          */
  35         cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
  36         return 1;
  37 }
  38 __setup("irqaffinity=", irq_affinity_setup);
  39
  40 static void __init init_irq_default_affinity(void)
  41 {
  42         if (!cpumask_available(irq_default_affinity))
  43                 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
  44         if (cpumask_empty(irq_default_affinity))
  45                 cpumask_setall(irq_default_affinity);
  46 }
  47 #else
  48 static void __init init_irq_default_affinity(void)
  49 {
  50 }
  51 #endif
  52
  53 #ifdef CONFIG_SMP
  54 static int alloc_masks(struct irq_desc *desc, int node)
  55 {
  56         if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
  57                                      GFP_KERNEL, node))
  58                 return -ENOMEM;
  59
  60 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  61         if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
  62                                      GFP_KERNEL, node)) {
  63                 free_cpumask_var(desc->irq_common_data.affinity);
  64                 return -ENOMEM;
  65         }
  66 #endif
  67
  68 #ifdef CONFIG_GENERIC_PENDING_IRQ
  69         if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
  70 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  71                 free_cpumask_var(desc->irq_common_data.effective_affinity);
  72 #endif
  73                 free_cpumask_var(desc->irq_common_data.affinity);
  74                 return -ENOMEM;
  75         }
  76 #endif
  77         return 0;
  78 }
  79
  80 static void desc_smp_init(struct irq_desc *desc, int node,
  81                           const struct cpumask *affinity)
  82 {
  83         if (!affinity)
  84                 affinity = irq_default_affinity;
  85         cpumask_copy(desc->irq_common_data.affinity, affinity);
  86
  87 #ifdef CONFIG_GENERIC_PENDING_IRQ
  88         cpumask_clear(desc->pending_mask);
  89 #endif
  90 #ifdef CONFIG_NUMA
  91         desc->irq_common_data.node = node;
  92 #endif
  93 }
  94
  95 #else
  96 static inline int
  97 alloc_masks(struct irq_desc *desc, int node) { return 0; }
  98 static inline void
  99 desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
 100 #endif
 101
 102 static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
 103                               const struct cpumask *affinity, struct module *owner)
 104 {
 105         int cpu;
 106
 107         desc->irq_common_data.handler_data = NULL;
 108         desc->irq_common_data.msi_desc = NULL;
 109
 110         desc->irq_data.common = &desc->irq_common_data;
 111         desc->irq_data.irq = irq;
 112         desc->irq_data.chip = &no_irq_chip;
 113         desc->irq_data.chip_data = NULL;
 114         irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
 115         irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 116         irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 117         desc->handle_irq = handle_bad_irq;
 118         desc->depth = 1;
 119         desc->irq_count = 0;
 120         desc->irqs_unhandled = 0;
 121         desc->tot_count = 0;
 122         desc->name = NULL;
 123         desc->owner = owner;
 124         for_each_possible_cpu(cpu)
 125                 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
 126         desc_smp_init(desc, node, affinity);
 127 }
 128
 129 int nr_irqs = NR_IRQS;
 130 EXPORT_SYMBOL_GPL(nr_irqs);
 131
 132 static DEFINE_MUTEX(sparse_irq_lock);
 133 static struct maple_tree sparse_irqs = MTREE_INIT_EXT(sparse_irqs,
 134                                         MT_FLAGS_ALLOC_RANGE |
 135                                         MT_FLAGS_LOCK_EXTERN |
 136                                         MT_FLAGS_USE_RCU,
 137                                         sparse_irq_lock);
 138
 139 static int irq_find_free_area(unsigned int from, unsigned int cnt)
 140 {
 141         MA_STATE(mas, &sparse_irqs, 0, 0);
 142
 143         if (mas_empty_area(&mas, from, MAX_SPARSE_IRQS, cnt))
 144                 return -ENOSPC;
 145         return mas.index;
 146 }
 147
 148 static unsigned int irq_find_at_or_after(unsigned int offset)
 149 {
 150         unsigned long index = offset;
 151         struct irq_desc *desc = mt_find(&sparse_irqs, &index, nr_irqs);
 152
 153         return desc ? irq_desc_get_irq(desc) : nr_irqs;
 154 }
 155
 156 static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
 157 {
 158         MA_STATE(mas, &sparse_irqs, irq, irq);
 159         WARN_ON(mas_store_gfp(&mas, desc, GFP_KERNEL) != 0);
 160 }
 161
 162 static void delete_irq_desc(unsigned int irq)
 163 {
 164         MA_STATE(mas, &sparse_irqs, irq, irq);
 165         mas_erase(&mas);
 166 }
 167
 168 #ifdef CONFIG_SPARSE_IRQ
 169
 170 static void irq_kobj_release(struct kobject *kobj);
 171
 172 #ifdef CONFIG_SYSFS
 173 static struct kobject *irq_kobj_base;
 174
 175 #define IRQ_ATTR_RO(_name) \
 176 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 177
 178 static ssize_t per_cpu_count_show(struct kobject *kobj,
 179                                   struct kobj_attribute *attr, char *buf)
 180 {
 181         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 182         ssize_t ret = 0;
 183         char *p = "";
 184         int cpu;
 185
 186         for_each_possible_cpu(cpu) {
 187                 unsigned int c = irq_desc_kstat_cpu(desc, cpu);
 188
 189                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
 190                 p = ",";
 191         }
 192
 193         ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 194         return ret;
 195 }
 196 IRQ_ATTR_RO(per_cpu_count);
 197
 198 static ssize_t chip_name_show(struct kobject *kobj,
 199                               struct kobj_attribute *attr, char *buf)
 200 {
 201         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 202         ssize_t ret = 0;
 203
 204         raw_spin_lock_irq(&desc->lock);
 205         if (desc->irq_data.chip && desc->irq_data.chip->name) {
 206                 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
 207                                 desc->irq_data.chip->name);
 208         }
 209         raw_spin_unlock_irq(&desc->lock);
 210
 211         return ret;
 212 }
 213 IRQ_ATTR_RO(chip_name);
 214
 215 static ssize_t hwirq_show(struct kobject *kobj,
 216                           struct kobj_attribute *attr, char *buf)
 217 {
 218         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 219         ssize_t ret = 0;
 220
 221         raw_spin_lock_irq(&desc->lock);
 222         if (desc->irq_data.domain)
 223                 ret = sprintf(buf, "%lu\n", desc->irq_data.hwirq);
 224         raw_spin_unlock_irq(&desc->lock);
 225
 226         return ret;
 227 }
 228 IRQ_ATTR_RO(hwirq);
 229
 230 static ssize_t type_show(struct kobject *kobj,
 231                          struct kobj_attribute *attr, char *buf)
 232 {
 233         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 234         ssize_t ret = 0;
 235
 236         raw_spin_lock_irq(&desc->lock);
 237         ret = sprintf(buf, "%s\n",
 238                       irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
 239         raw_spin_unlock_irq(&desc->lock);
 240
 241         return ret;
 242
 243 }
 244 IRQ_ATTR_RO(type);
 245
 246 static ssize_t wakeup_show(struct kobject *kobj,
 247                            struct kobj_attribute *attr, char *buf)
 248 {
 249         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 250         ssize_t ret = 0;
 251
 252         raw_spin_lock_irq(&desc->lock);
 253         ret = sprintf(buf, "%s\n",
 254                       irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
 255         raw_spin_unlock_irq(&desc->lock);
 256
 257         return ret;
 258
 259 }
 260 IRQ_ATTR_RO(wakeup);
 261
 262 static ssize_t name_show(struct kobject *kobj,
 263                          struct kobj_attribute *attr, char *buf)
 264 {
 265         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 266         ssize_t ret = 0;
 267
 268         raw_spin_lock_irq(&desc->lock);
 269         if (desc->name)
 270                 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
 271         raw_spin_unlock_irq(&desc->lock);
 272
 273         return ret;
 274 }
 275 IRQ_ATTR_RO(name);
 276
 277 static ssize_t actions_show(struct kobject *kobj,
 278                             struct kobj_attribute *attr, char *buf)
 279 {
 280         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 281         struct irqaction *action;
 282         ssize_t ret = 0;
 283         char *p = "";
 284
 285         raw_spin_lock_irq(&desc->lock);
 286         for_each_action_of_desc(desc, action) {
 287                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
 288                                  p, action->name);
 289                 p = ",";
 290         }
 291         raw_spin_unlock_irq(&desc->lock);
 292
 293         if (ret)
 294                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
 295
 296         return ret;
 297 }
 298 IRQ_ATTR_RO(actions);
 299
 300 static struct attribute *irq_attrs[] = {
 301         &per_cpu_count_attr.attr,
 302         &chip_name_attr.attr,
 303         &hwirq_attr.attr,
 304         &type_attr.attr,
 305         &wakeup_attr.attr,
 306         &name_attr.attr,
 307         &actions_attr.attr,
 308         NULL
 309 };
 310 ATTRIBUTE_GROUPS(irq);
 311
 312 static const struct kobj_type irq_kobj_type = {
 313         .release        = irq_kobj_release,
 314         .sysfs_ops      = &kobj_sysfs_ops,
 315         .default_groups = irq_groups,
 316 };
 317
 318 static void irq_sysfs_add(int irq, struct irq_desc *desc)
 319 {
 320         if (irq_kobj_base) {
 321                 /*
 322                  * Continue even in case of failure as this is nothing
 323                  * crucial and failures in the late irq_sysfs_init()
 324                  * cannot be rolled back.
 325                  */
 326                 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
 327                         pr_warn("Failed to add kobject for irq %d\n", irq);
 328                 else
 329                         desc->istate |= IRQS_SYSFS;
 330         }
 331 }
 332
 333 static void irq_sysfs_del(struct irq_desc *desc)
 334 {
 335         /*
 336          * Only invoke kobject_del() when kobject_add() was successfully
 337          * invoked for the descriptor. This covers both early boot, where
 338          * sysfs is not initialized yet, and the case of a failed
 339          * kobject_add() invocation.
 340          */
 341         if (desc->istate & IRQS_SYSFS)
 342                 kobject_del(&desc->kobj);
 343 }
 344
 345 static int __init irq_sysfs_init(void)
 346 {
 347         struct irq_desc *desc;
 348         int irq;
 349
 350         /* Prevent concurrent irq alloc/free */
 351         irq_lock_sparse();
 352
 353         irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
 354         if (!irq_kobj_base) {
 355                 irq_unlock_sparse();
 356                 return -ENOMEM;
 357         }
 358
 359         /* Add the already allocated interrupts */
 360         for_each_irq_desc(irq, desc)
 361                 irq_sysfs_add(irq, desc);
 362         irq_unlock_sparse();
 363
 364         return 0;
 365 }
 366 postcore_initcall(irq_sysfs_init);
 367
 368 #else /* !CONFIG_SYSFS */
 369
 370 static const struct kobj_type irq_kobj_type = {
 371         .release        = irq_kobj_release,
 372 };
 373
 374 static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
 375 static void irq_sysfs_del(struct irq_desc *desc) {}
 376
 377 #endif /* CONFIG_SYSFS */
 378
 379 struct irq_desc *irq_to_desc(unsigned int irq)
 380 {
 381         return mtree_load(&sparse_irqs, irq);
 382 }
 383 #ifdef CONFIG_KVM_BOOK3S_64_HV_MODULE
 384 EXPORT_SYMBOL_GPL(irq_to_desc);
 385 #endif
 386
 387 #ifdef CONFIG_SMP
 388 static void free_masks(struct irq_desc *desc)
 389 {
 390 #ifdef CONFIG_GENERIC_PENDING_IRQ
 391         free_cpumask_var(desc->pending_mask);
 392 #endif
 393         free_cpumask_var(desc->irq_common_data.affinity);
 394 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 395         free_cpumask_var(desc->irq_common_data.effective_affinity);
 396 #endif
 397 }
 398 #else
 399 static inline void free_masks(struct irq_desc *desc) { }
 400 #endif
 401
 402 void irq_lock_sparse(void)
 403 {
 404         mutex_lock(&sparse_irq_lock);
 405 }
 406
 407 void irq_unlock_sparse(void)
 408 {
 409         mutex_unlock(&sparse_irq_lock);
 410 }
 411
 412 static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 413                                    const struct cpumask *affinity,
 414                                    struct module *owner)
 415 {
 416         struct irq_desc *desc;
 417
 418         desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
 419         if (!desc)
 420                 return NULL;
 421         /* allocate based on nr_cpu_ids */
 422         desc->kstat_irqs = alloc_percpu(unsigned int);
 423         if (!desc->kstat_irqs)
 424                 goto err_desc;
 425
 426         if (alloc_masks(desc, node))
 427                 goto err_kstat;
 428
 429         raw_spin_lock_init(&desc->lock);
 430         lockdep_set_class(&desc->lock, &irq_desc_lock_class);
 431         mutex_init(&desc->request_mutex);
 432         init_rcu_head(&desc->rcu);
 433         init_waitqueue_head(&desc->wait_for_threads);
 434
 435         desc_set_defaults(irq, desc, node, affinity, owner);
 436         irqd_set(&desc->irq_data, flags);
 437         kobject_init(&desc->kobj, &irq_kobj_type);
 438         irq_resend_init(desc);
 439
 440         return desc;
 441
 442 err_kstat:
 443         free_percpu(desc->kstat_irqs);
 444 err_desc:
 445         kfree(desc);
 446         return NULL;
 447 }
 448
 449 static void irq_kobj_release(struct kobject *kobj)
 450 {
 451         struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 452
 453         free_masks(desc);
 454         free_percpu(desc->kstat_irqs);
 455         kfree(desc);
 456 }
 457
 458 static void delayed_free_desc(struct rcu_head *rhp)
 459 {
 460         struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
 461
 462         kobject_put(&desc->kobj);
 463 }
 464
 465 static void free_desc(unsigned int irq)
 466 {
 467         struct irq_desc *desc = irq_to_desc(irq);
 468
 469         irq_remove_debugfs_entry(desc);
 470         unregister_irq_proc(irq, desc);
 471
 472         /*
 473          * sparse_irq_lock protects also show_interrupts() and
 474          * kstat_irq_usr(). Once we deleted the descriptor from the
 475          * sparse tree we can free it. Access in proc will fail to
 476          * lookup the descriptor.
 477          *
 478          * The sysfs entry must be serialized against a concurrent
 479          * irq_sysfs_init() as well.
 480          */
 481         irq_sysfs_del(desc);
 482         delete_irq_desc(irq);
 483
 484         /*
 485          * We free the descriptor, masks and stat fields via RCU. That
 486          * allows demultiplex interrupts to do rcu based management of
 487          * the child interrupts.
 488          * This also allows us to use rcu in kstat_irqs_usr().
 489          */
 490         call_rcu(&desc->rcu, delayed_free_desc);
 491 }
 492
 493 static int alloc_descs(unsigned int start, unsigned int cnt, int node,
 494                        const struct irq_affinity_desc *affinity,
 495                        struct module *owner)
 496 {
 497         struct irq_desc *desc;
 498         int i;
 499
 500         /* Validate affinity mask(s) */
 501         if (affinity) {
 502                 for (i = 0; i < cnt; i++) {
 503                         if (cpumask_empty(&affinity[i].mask))
 504                                 return -EINVAL;
 505                 }
 506         }
 507
 508         for (i = 0; i < cnt; i++) {
 509                 const struct cpumask *mask = NULL;
 510                 unsigned int flags = 0;
 511
 512                 if (affinity) {
 513                         if (affinity->is_managed) {
 514                                 flags = IRQD_AFFINITY_MANAGED |
 515                                         IRQD_MANAGED_SHUTDOWN;
 516                         }
 517                         mask = &affinity->mask;
 518                         node = cpu_to_node(cpumask_first(mask));
 519                         affinity++;
 520                 }
 521
 522                 desc = alloc_desc(start + i, node, flags, mask, owner);
 523                 if (!desc)
 524                         goto err;
 525                 irq_insert_desc(start + i, desc);
 526                 irq_sysfs_add(start + i, desc);
 527                 irq_add_debugfs_entry(start + i, desc);
 528         }
 529         return start;
 530
 531 err:
 532         for (i--; i >= 0; i--)
 533                 free_desc(start + i);
 534         return -ENOMEM;
 535 }
 536
 537 static int irq_expand_nr_irqs(unsigned int nr)
 538 {
 539         if (nr > MAX_SPARSE_IRQS)
 540                 return -ENOMEM;
 541         nr_irqs = nr;
 542         return 0;
 543 }
 544
 545 int __init early_irq_init(void)
 546 {
 547         int i, initcnt, node = first_online_node;
 548         struct irq_desc *desc;
 549
 550         init_irq_default_affinity();
 551
 552         /* Let arch update nr_irqs and return the nr of preallocated irqs */
 553         initcnt = arch_probe_nr_irqs();
 554         printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
 555                NR_IRQS, nr_irqs, initcnt);
 556
 557         if (WARN_ON(nr_irqs > MAX_SPARSE_IRQS))
 558                 nr_irqs = MAX_SPARSE_IRQS;
 559
 560         if (WARN_ON(initcnt > MAX_SPARSE_IRQS))
 561                 initcnt = MAX_SPARSE_IRQS;
 562
 563         if (initcnt > nr_irqs)
 564                 nr_irqs = initcnt;
 565
 566         for (i = 0; i < initcnt; i++) {
 567                 desc = alloc_desc(i, node, 0, NULL, NULL);
 568                 irq_insert_desc(i, desc);
 569         }
 570         return arch_early_irq_init();
 571 }
 572
 573 #else /* !CONFIG_SPARSE_IRQ */
 574
 575 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 576         [0 ... NR_IRQS-1] = {
 577                 .handle_irq     = handle_bad_irq,
 578                 .depth          = 1,
 579                 .lock           = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
 580         }
 581 };
 582
 583 int __init early_irq_init(void)
 584 {
 585         int count, i, node = first_online_node;
 586         struct irq_desc *desc;
 587
 588         init_irq_default_affinity();
 589
 590         printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
 591
 592         desc = irq_desc;
 593         count = ARRAY_SIZE(irq_desc);
 594
 595         for (i = 0; i < count; i++) {
 596                 desc[i].kstat_irqs = alloc_percpu(unsigned int);
 597                 alloc_masks(&desc[i], node);
 598                 raw_spin_lock_init(&desc[i].lock);
 599                 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
 600                 mutex_init(&desc[i].request_mutex);
 601                 init_waitqueue_head(&desc[i].wait_for_threads);
 602                 desc_set_defaults(i, &desc[i], node, NULL, NULL);
 603                 irq_resend_init(&desc[i]);
 604         }
 605         return arch_early_irq_init();
 606 }
 607
 608 struct irq_desc *irq_to_desc(unsigned int irq)
 609 {
 610         return (irq < NR_IRQS) ? irq_desc + irq : NULL;
 611 }
 612 EXPORT_SYMBOL(irq_to_desc);
 613
 614 static void free_desc(unsigned int irq)
 615 {
 616         struct irq_desc *desc = irq_to_desc(irq);
 617         unsigned long flags;
 618
 619         raw_spin_lock_irqsave(&desc->lock, flags);
 620         desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
 621         raw_spin_unlock_irqrestore(&desc->lock, flags);
 622         delete_irq_desc(irq);
 623 }
 624
 625 static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 626                               const struct irq_affinity_desc *affinity,
 627                               struct module *owner)
 628 {
 629         u32 i;
 630
 631         for (i = 0; i < cnt; i++) {
 632                 struct irq_desc *desc = irq_to_desc(start + i);
 633
 634                 desc->owner = owner;
 635                 irq_insert_desc(start + i, desc);
 636         }
 637         return start;
 638 }
 639
 640 static int irq_expand_nr_irqs(unsigned int nr)
 641 {
 642         return -ENOMEM;
 643 }
 644
 645 void irq_mark_irq(unsigned int irq)
 646 {
 647         mutex_lock(&sparse_irq_lock);
 648         irq_insert_desc(irq, irq_desc + irq);
 649         mutex_unlock(&sparse_irq_lock);
 650 }
 651
 652 #ifdef CONFIG_GENERIC_IRQ_LEGACY
 653 void irq_init_desc(unsigned int irq)
 654 {
 655         free_desc(irq);
 656 }
 657 #endif
 658
 659 #endif /* !CONFIG_SPARSE_IRQ */
 660
 661 int handle_irq_desc(struct irq_desc *desc)
 662 {
 663         struct irq_data *data;
 664
 665         if (!desc)
 666                 return -EINVAL;
 667
 668         data = irq_desc_get_irq_data(desc);
 669         if (WARN_ON_ONCE(!in_hardirq() && handle_enforce_irqctx(data)))
 670                 return -EPERM;
 671
 672         generic_handle_irq_desc(desc);
 673         return 0;
 674 }
 675
 676 /**
 677  * generic_handle_irq - Invoke the handler for a particular irq
 678  * @irq:        The irq number to handle
 679  *
 680  * Returns:     0 on success, or -EINVAL if conversion has failed
 681  *
 682  *              This function must be called from an IRQ context with irq regs
 683  *              initialized.
 684   */
 685 int generic_handle_irq(unsigned int irq)
 686 {
 687         return handle_irq_desc(irq_to_desc(irq));
 688 }
 689 EXPORT_SYMBOL_GPL(generic_handle_irq);
 690
 691 /**
 692  * generic_handle_irq_safe - Invoke the handler for a particular irq from any
 693  *                           context.
 694  * @irq:        The irq number to handle
 695  *
 696  * Returns:     0 on success, a negative value on error.
 697  *
 698  * This function can be called from any context (IRQ or process context). It
 699  * will report an error if not invoked from IRQ context and the irq has been
 700  * marked to enforce IRQ-context only.
 701  */
 702 int generic_handle_irq_safe(unsigned int irq)
 703 {
 704         unsigned long flags;
 705         int ret;
 706
 707         local_irq_save(flags);
 708         ret = handle_irq_desc(irq_to_desc(irq));
 709         local_irq_restore(flags);
 710         return ret;
 711 }
 712 EXPORT_SYMBOL_GPL(generic_handle_irq_safe);
 713
 714 #ifdef CONFIG_IRQ_DOMAIN
 715 /**
 716  * generic_handle_domain_irq - Invoke the handler for a HW irq belonging
 717  *                             to a domain.
 718  * @domain:     The domain where to perform the lookup
 719  * @hwirq:      The HW irq number to convert to a logical one
 720  *
 721  * Returns:     0 on success, or -EINVAL if conversion has failed
 722  *
 723  *              This function must be called from an IRQ context with irq regs
 724  *              initialized.
 725  */
 726 int generic_handle_domain_irq(struct irq_domain *domain, unsigned int hwirq)
 727 {
 728         return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 729 }
 730 EXPORT_SYMBOL_GPL(generic_handle_domain_irq);
 731
 732  /**
 733  * generic_handle_irq_safe - Invoke the handler for a HW irq belonging
 734  *                           to a domain from any context.
 735  * @domain:     The domain where to perform the lookup
 736  * @hwirq:      The HW irq number to convert to a logical one
 737  *
 738  * Returns:     0 on success, a negative value on error.
 739  *
 740  * This function can be called from any context (IRQ or process
 741  * context). If the interrupt is marked as 'enforce IRQ-context only' then
 742  * the function must be invoked from hard interrupt context.
 743  */
 744 int generic_handle_domain_irq_safe(struct irq_domain *domain, unsigned int hwirq)
 745 {
 746         unsigned long flags;
 747         int ret;
 748
 749         local_irq_save(flags);
 750         ret = handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 751         local_irq_restore(flags);
 752         return ret;
 753 }
 754 EXPORT_SYMBOL_GPL(generic_handle_domain_irq_safe);
 755
 756 /**
 757  * generic_handle_domain_nmi - Invoke the handler for a HW nmi belonging
 758  *                             to a domain.
 759  * @domain:     The domain where to perform the lookup
 760  * @hwirq:      The HW irq number to convert to a logical one
 761  *
 762  * Returns:     0 on success, or -EINVAL if conversion has failed
 763  *
 764  *              This function must be called from an NMI context with irq regs
 765  *              initialized.
 766  **/
 767 int generic_handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq)
 768 {
 769         WARN_ON_ONCE(!in_nmi());
 770         return handle_irq_desc(irq_resolve_mapping(domain, hwirq));
 771 }
 772 #endif
 773
 774 /* Dynamic interrupt handling */
 775
 776 /**
 777  * irq_free_descs - free irq descriptors
 778  * @from:       Start of descriptor range
 779  * @cnt:        Number of consecutive irqs to free
 780  */
 781 void irq_free_descs(unsigned int from, unsigned int cnt)
 782 {
 783         int i;
 784
 785         if (from >= nr_irqs || (from + cnt) > nr_irqs)
 786                 return;
 787
 788         mutex_lock(&sparse_irq_lock);
 789         for (i = 0; i < cnt; i++)
 790                 free_desc(from + i);
 791
 792         mutex_unlock(&sparse_irq_lock);
 793 }
 794 EXPORT_SYMBOL_GPL(irq_free_descs);
 795
 796 /**
 797  * __irq_alloc_descs - allocate and initialize a range of irq descriptors
 798  * @irq:        Allocate for specific irq number if irq >= 0
 799  * @from:       Start the search from this irq number
 800  * @cnt:        Number of consecutive irqs to allocate.
 801  * @node:       Preferred node on which the irq descriptor should be allocated
 802  * @owner:      Owning module (can be NULL)
 803  * @affinity:   Optional pointer to an affinity mask array of size @cnt which
 804  *              hints where the irq descriptors should be allocated and which
 805  *              default affinities to use
 806  *
 807  * Returns the first irq number or error code
 808  */
 809 int __ref
 810 __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 811                   struct module *owner, const struct irq_affinity_desc *affinity)
 812 {
 813         int start, ret;
 814
 815         if (!cnt)
 816                 return -EINVAL;
 817
 818         if (irq >= 0) {
 819                 if (from > irq)
 820                         return -EINVAL;
 821                 from = irq;
 822         } else {
 823                 /*
 824                  * For interrupts which are freely allocated the
 825                  * architecture can force a lower bound to the @from
 826                  * argument. x86 uses this to exclude the GSI space.
 827                  */
 828                 from = arch_dynirq_lower_bound(from);
 829         }
 830
 831         mutex_lock(&sparse_irq_lock);
 832
 833         start = irq_find_free_area(from, cnt);
 834         ret = -EEXIST;
 835         if (irq >=0 && start != irq)
 836                 goto unlock;
 837
 838         if (start + cnt > nr_irqs) {
 839                 ret = irq_expand_nr_irqs(start + cnt);
 840                 if (ret)
 841                         goto unlock;
 842         }
 843         ret = alloc_descs(start, cnt, node, affinity, owner);
 844 unlock:
 845         mutex_unlock(&sparse_irq_lock);
 846         return ret;
 847 }
 848 EXPORT_SYMBOL_GPL(__irq_alloc_descs);
 849
 850 /**
 851  * irq_get_next_irq - get next allocated irq number
 852  * @offset:     where to start the search
 853  *
 854  * Returns next irq number after offset or nr_irqs if none is found.
 855  */
 856 unsigned int irq_get_next_irq(unsigned int offset)
 857 {
 858         return irq_find_at_or_after(offset);
 859 }
 860
 861 struct irq_desc *
 862 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
 863                     unsigned int check)
 864 {
 865         struct irq_desc *desc = irq_to_desc(irq);
 866
 867         if (desc) {
 868                 if (check & _IRQ_DESC_CHECK) {
 869                         if ((check & _IRQ_DESC_PERCPU) &&
 870                             !irq_settings_is_per_cpu_devid(desc))
 871                                 return NULL;
 872
 873                         if (!(check & _IRQ_DESC_PERCPU) &&
 874                             irq_settings_is_per_cpu_devid(desc))
 875                                 return NULL;
 876                 }
 877
 878                 if (bus)
 879                         chip_bus_lock(desc);
 880                 raw_spin_lock_irqsave(&desc->lock, *flags);
 881         }
 882         return desc;
 883 }
 884
 885 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
 886         __releases(&desc->lock)
 887 {
 888         raw_spin_unlock_irqrestore(&desc->lock, flags);
 889         if (bus)
 890                 chip_bus_sync_unlock(desc);
 891 }
 892
 893 int irq_set_percpu_devid_partition(unsigned int irq,
 894                                    const struct cpumask *affinity)
 895 {
 896         struct irq_desc *desc = irq_to_desc(irq);
 897
 898         if (!desc)
 899                 return -EINVAL;
 900
 901         if (desc->percpu_enabled)
 902                 return -EINVAL;
 903
 904         desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
 905
 906         if (!desc->percpu_enabled)
 907                 return -ENOMEM;
 908
 909         if (affinity)
 910                 desc->percpu_affinity = affinity;
 911         else
 912                 desc->percpu_affinity = cpu_possible_mask;
 913
 914         irq_set_percpu_devid_flags(irq);
 915         return 0;
 916 }
 917
 918 int irq_set_percpu_devid(unsigned int irq)
 919 {
 920         return irq_set_percpu_devid_partition(irq, NULL);
 921 }
 922
 923 int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
 924 {
 925         struct irq_desc *desc = irq_to_desc(irq);
 926
 927         if (!desc || !desc->percpu_enabled)
 928                 return -EINVAL;
 929
 930         if (affinity)
 931                 cpumask_copy(affinity, desc->percpu_affinity);
 932
 933         return 0;
 934 }
 935 EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
 936
 937 void kstat_incr_irq_this_cpu(unsigned int irq)
 938 {
 939         kstat_incr_irqs_this_cpu(irq_to_desc(irq));
 940 }
 941
 942 /**
 943  * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
 944  * @irq:        The interrupt number
 945  * @cpu:        The cpu number
 946  *
 947  * Returns the sum of interrupt counts on @cpu since boot for
 948  * @irq. The caller must ensure that the interrupt is not removed
 949  * concurrently.
 950  */
 951 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 952 {
 953         struct irq_desc *desc = irq_to_desc(irq);
 954
 955         return desc && desc->kstat_irqs ?
 956                         *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
 957 }
 958
 959 static bool irq_is_nmi(struct irq_desc *desc)
 960 {
 961         return desc->istate & IRQS_NMI;
 962 }
 963
 964 static unsigned int kstat_irqs(unsigned int irq)
 965 {
 966         struct irq_desc *desc = irq_to_desc(irq);
 967         unsigned int sum = 0;
 968         int cpu;
 969
 970         if (!desc || !desc->kstat_irqs)
 971                 return 0;
 972         if (!irq_settings_is_per_cpu_devid(desc) &&
 973             !irq_settings_is_per_cpu(desc) &&
 974             !irq_is_nmi(desc))
 975                 return data_race(desc->tot_count);
 976
 977         for_each_possible_cpu(cpu)
 978                 sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
 979         return sum;
 980 }
 981
 982 /**
 983  * kstat_irqs_usr - Get the statistics for an interrupt from thread context
 984  * @irq:        The interrupt number
 985  *
 986  * Returns the sum of interrupt counts on all cpus since boot for @irq.
 987  *
 988  * It uses rcu to protect the access since a concurrent removal of an
 989  * interrupt descriptor is observing an rcu grace period before
 990  * delayed_free_desc()/irq_kobj_release().
 991  */
 992 unsigned int kstat_irqs_usr(unsigned int irq)
 993 {
 994         unsigned int sum;
 995
 996         rcu_read_lock();
 997         sum = kstat_irqs(irq);
 998         rcu_read_unlock();
 999         return sum;
1000 }
1001
1002 #ifdef CONFIG_LOCKDEP
1003 void __irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
1004                              struct lock_class_key *request_class)
1005 {
1006         struct irq_desc *desc = irq_to_desc(irq);
1007
1008         if (desc) {
1009                 lockdep_set_class(&desc->lock, lock_class);
1010                 lockdep_set_class(&desc->request_mutex, request_class);
1011         }
1012 }
1013 EXPORT_SYMBOL_GPL(__irq_set_lockdep_class);
1014 #endif