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v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
 
 
  3 * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
  4 *
  5 * This file contains the /proc/irq/ handling code.
  6 */
  7
  8#include <linux/irq.h>
  9#include <linux/gfp.h>
 10#include <linux/proc_fs.h>
 11#include <linux/seq_file.h>
 12#include <linux/interrupt.h>
 13#include <linux/kernel_stat.h>
 14#include <linux/mutex.h>
 15
 16#include "internals.h"
 17
 18/*
 19 * Access rules:
 20 *
 21 * procfs protects read/write of /proc/irq/N/ files against a
 22 * concurrent free of the interrupt descriptor. remove_proc_entry()
 23 * immediately prevents new read/writes to happen and waits for
 24 * already running read/write functions to complete.
 25 *
 26 * We remove the proc entries first and then delete the interrupt
 27 * descriptor from the radix tree and free it. So it is guaranteed
 28 * that irq_to_desc(N) is valid as long as the read/writes are
 29 * permitted by procfs.
 30 *
 31 * The read from /proc/interrupts is a different problem because there
 32 * is no protection. So the lookup and the access to irqdesc
 33 * information must be protected by sparse_irq_lock.
 34 */
 35static struct proc_dir_entry *root_irq_dir;
 36
 37#ifdef CONFIG_SMP
 38
 39enum {
 40	AFFINITY,
 41	AFFINITY_LIST,
 42	EFFECTIVE,
 43	EFFECTIVE_LIST,
 44};
 45
 46static int show_irq_affinity(int type, struct seq_file *m)
 47{
 48	struct irq_desc *desc = irq_to_desc((long)m->private);
 49	const struct cpumask *mask;
 50
 51	switch (type) {
 52	case AFFINITY:
 53	case AFFINITY_LIST:
 54		mask = desc->irq_common_data.affinity;
 55#ifdef CONFIG_GENERIC_PENDING_IRQ
 56		if (irqd_is_setaffinity_pending(&desc->irq_data))
 57			mask = desc->pending_mask;
 58#endif
 59		break;
 60	case EFFECTIVE:
 61	case EFFECTIVE_LIST:
 62#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 63		mask = irq_data_get_effective_affinity_mask(&desc->irq_data);
 64		break;
 65#endif
 66	default:
 67		return -EINVAL;
 68	}
 69
 70	switch (type) {
 71	case AFFINITY_LIST:
 72	case EFFECTIVE_LIST:
 73		seq_printf(m, "%*pbl\n", cpumask_pr_args(mask));
 74		break;
 75	case AFFINITY:
 76	case EFFECTIVE:
 77		seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
 78		break;
 79	}
 80	return 0;
 81}
 82
 83static int irq_affinity_hint_proc_show(struct seq_file *m, void *v)
 84{
 85	struct irq_desc *desc = irq_to_desc((long)m->private);
 86	unsigned long flags;
 87	cpumask_var_t mask;
 88
 89	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 90		return -ENOMEM;
 91
 92	raw_spin_lock_irqsave(&desc->lock, flags);
 93	if (desc->affinity_hint)
 94		cpumask_copy(mask, desc->affinity_hint);
 95	raw_spin_unlock_irqrestore(&desc->lock, flags);
 96
 97	seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
 98	free_cpumask_var(mask);
 99
100	return 0;
101}
102
 
 
 
 
103int no_irq_affinity;
104static int irq_affinity_proc_show(struct seq_file *m, void *v)
105{
106	return show_irq_affinity(AFFINITY, m);
107}
108
109static int irq_affinity_list_proc_show(struct seq_file *m, void *v)
110{
111	return show_irq_affinity(AFFINITY_LIST, m);
112}
113
114#ifndef CONFIG_AUTO_IRQ_AFFINITY
115static inline int irq_select_affinity_usr(unsigned int irq)
116{
117	/*
118	 * If the interrupt is started up already then this fails. The
119	 * interrupt is assigned to an online CPU already. There is no
120	 * point to move it around randomly. Tell user space that the
121	 * selected mask is bogus.
122	 *
123	 * If not then any change to the affinity is pointless because the
124	 * startup code invokes irq_setup_affinity() which will select
125	 * a online CPU anyway.
126	 */
127	return -EINVAL;
128}
129#else
130/* ALPHA magic affinity auto selector. Keep it for historical reasons. */
131static inline int irq_select_affinity_usr(unsigned int irq)
132{
133	return irq_select_affinity(irq);
134}
135#endif
136
137static ssize_t write_irq_affinity(int type, struct file *file,
138		const char __user *buffer, size_t count, loff_t *pos)
139{
140	unsigned int irq = (int)(long)pde_data(file_inode(file));
141	cpumask_var_t new_value;
142	int err;
143
144	if (!irq_can_set_affinity_usr(irq) || no_irq_affinity)
145		return -EIO;
146
147	if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
148		return -ENOMEM;
149
150	if (type)
151		err = cpumask_parselist_user(buffer, count, new_value);
152	else
153		err = cpumask_parse_user(buffer, count, new_value);
154	if (err)
155		goto free_cpumask;
156
 
 
 
 
 
157	/*
158	 * Do not allow disabling IRQs completely - it's a too easy
159	 * way to make the system unusable accidentally :-) At least
160	 * one online CPU still has to be targeted.
161	 */
162	if (!cpumask_intersects(new_value, cpu_online_mask)) {
163		/*
164		 * Special case for empty set - allow the architecture code
165		 * to set default SMP affinity.
166		 */
167		err = irq_select_affinity_usr(irq) ? -EINVAL : count;
168	} else {
169		err = irq_set_affinity(irq, new_value);
170		if (!err)
171			err = count;
172	}
173
174free_cpumask:
175	free_cpumask_var(new_value);
176	return err;
177}
178
179static ssize_t irq_affinity_proc_write(struct file *file,
180		const char __user *buffer, size_t count, loff_t *pos)
181{
182	return write_irq_affinity(0, file, buffer, count, pos);
183}
184
185static ssize_t irq_affinity_list_proc_write(struct file *file,
186		const char __user *buffer, size_t count, loff_t *pos)
187{
188	return write_irq_affinity(1, file, buffer, count, pos);
189}
190
191static int irq_affinity_proc_open(struct inode *inode, struct file *file)
192{
193	return single_open(file, irq_affinity_proc_show, pde_data(inode));
194}
195
196static int irq_affinity_list_proc_open(struct inode *inode, struct file *file)
197{
198	return single_open(file, irq_affinity_list_proc_show, pde_data(inode));
199}
200
201static const struct proc_ops irq_affinity_proc_ops = {
202	.proc_open	= irq_affinity_proc_open,
203	.proc_read	= seq_read,
204	.proc_lseek	= seq_lseek,
205	.proc_release	= single_release,
206	.proc_write	= irq_affinity_proc_write,
207};
208
209static const struct proc_ops irq_affinity_list_proc_ops = {
210	.proc_open	= irq_affinity_list_proc_open,
211	.proc_read	= seq_read,
212	.proc_lseek	= seq_lseek,
213	.proc_release	= single_release,
214	.proc_write	= irq_affinity_list_proc_write,
215};
216
217#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
218static int irq_effective_aff_proc_show(struct seq_file *m, void *v)
219{
220	return show_irq_affinity(EFFECTIVE, m);
221}
 
222
223static int irq_effective_aff_list_proc_show(struct seq_file *m, void *v)
224{
225	return show_irq_affinity(EFFECTIVE_LIST, m);
226}
227#endif
 
 
228
229static int default_affinity_show(struct seq_file *m, void *v)
230{
231	seq_printf(m, "%*pb\n", cpumask_pr_args(irq_default_affinity));
232	return 0;
233}
234
235static ssize_t default_affinity_write(struct file *file,
236		const char __user *buffer, size_t count, loff_t *ppos)
237{
238	cpumask_var_t new_value;
239	int err;
240
241	if (!zalloc_cpumask_var(&new_value, GFP_KERNEL))
242		return -ENOMEM;
243
244	err = cpumask_parse_user(buffer, count, new_value);
245	if (err)
246		goto out;
247
 
 
 
 
 
248	/*
249	 * Do not allow disabling IRQs completely - it's a too easy
250	 * way to make the system unusable accidentally :-) At least
251	 * one online CPU still has to be targeted.
252	 */
253	if (!cpumask_intersects(new_value, cpu_online_mask)) {
254		err = -EINVAL;
255		goto out;
256	}
257
258	cpumask_copy(irq_default_affinity, new_value);
259	err = count;
260
261out:
262	free_cpumask_var(new_value);
263	return err;
264}
265
266static int default_affinity_open(struct inode *inode, struct file *file)
267{
268	return single_open(file, default_affinity_show, pde_data(inode));
269}
270
271static const struct proc_ops default_affinity_proc_ops = {
272	.proc_open	= default_affinity_open,
273	.proc_read	= seq_read,
274	.proc_lseek	= seq_lseek,
275	.proc_release	= single_release,
276	.proc_write	= default_affinity_write,
277};
278
279static int irq_node_proc_show(struct seq_file *m, void *v)
280{
281	struct irq_desc *desc = irq_to_desc((long) m->private);
282
283	seq_printf(m, "%d\n", irq_desc_get_node(desc));
284	return 0;
285}
 
 
 
 
 
 
 
 
 
 
 
 
286#endif
287
288static int irq_spurious_proc_show(struct seq_file *m, void *v)
289{
290	struct irq_desc *desc = irq_to_desc((long) m->private);
291
292	seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n",
293		   desc->irq_count, desc->irqs_unhandled,
294		   jiffies_to_msecs(desc->last_unhandled));
295	return 0;
296}
297
 
 
 
 
 
 
 
 
 
 
 
 
298#define MAX_NAMELEN 128
299
300static int name_unique(unsigned int irq, struct irqaction *new_action)
301{
302	struct irq_desc *desc = irq_to_desc(irq);
303	struct irqaction *action;
304	unsigned long flags;
305	int ret = 1;
306
307	raw_spin_lock_irqsave(&desc->lock, flags);
308	for_each_action_of_desc(desc, action) {
309		if ((action != new_action) && action->name &&
310				!strcmp(new_action->name, action->name)) {
311			ret = 0;
312			break;
313		}
314	}
315	raw_spin_unlock_irqrestore(&desc->lock, flags);
316	return ret;
317}
318
319void register_handler_proc(unsigned int irq, struct irqaction *action)
320{
321	char name [MAX_NAMELEN];
322	struct irq_desc *desc = irq_to_desc(irq);
323
324	if (!desc->dir || action->dir || !action->name ||
325					!name_unique(irq, action))
326		return;
327
 
328	snprintf(name, MAX_NAMELEN, "%s", action->name);
329
330	/* create /proc/irq/1234/handler/ */
331	action->dir = proc_mkdir(name, desc->dir);
332}
333
334#undef MAX_NAMELEN
335
336#define MAX_NAMELEN 10
337
338void register_irq_proc(unsigned int irq, struct irq_desc *desc)
339{
340	static DEFINE_MUTEX(register_lock);
341	void __maybe_unused *irqp = (void *)(unsigned long) irq;
342	char name [MAX_NAMELEN];
343
344	if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip))
345		return;
346
347	/*
348	 * irq directories are registered only when a handler is
349	 * added, not when the descriptor is created, so multiple
350	 * tasks might try to register at the same time.
351	 */
352	mutex_lock(&register_lock);
353
354	if (desc->dir)
355		goto out_unlock;
356
 
357	sprintf(name, "%d", irq);
358
359	/* create /proc/irq/1234 */
360	desc->dir = proc_mkdir(name, root_irq_dir);
361	if (!desc->dir)
362		goto out_unlock;
363
364#ifdef CONFIG_SMP
365	/* create /proc/irq/<irq>/smp_affinity */
366	proc_create_data("smp_affinity", 0644, desc->dir,
367			 &irq_affinity_proc_ops, irqp);
368
369	/* create /proc/irq/<irq>/affinity_hint */
370	proc_create_single_data("affinity_hint", 0444, desc->dir,
371			irq_affinity_hint_proc_show, irqp);
372
373	/* create /proc/irq/<irq>/smp_affinity_list */
374	proc_create_data("smp_affinity_list", 0644, desc->dir,
375			 &irq_affinity_list_proc_ops, irqp);
376
377	proc_create_single_data("node", 0444, desc->dir, irq_node_proc_show,
378			irqp);
379# ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
380	proc_create_single_data("effective_affinity", 0444, desc->dir,
381			irq_effective_aff_proc_show, irqp);
382	proc_create_single_data("effective_affinity_list", 0444, desc->dir,
383			irq_effective_aff_list_proc_show, irqp);
384# endif
385#endif
386	proc_create_single_data("spurious", 0444, desc->dir,
387			irq_spurious_proc_show, (void *)(long)irq);
 
388
389out_unlock:
390	mutex_unlock(&register_lock);
391}
392
393void unregister_irq_proc(unsigned int irq, struct irq_desc *desc)
394{
395	char name [MAX_NAMELEN];
396
397	if (!root_irq_dir || !desc->dir)
398		return;
399#ifdef CONFIG_SMP
400	remove_proc_entry("smp_affinity", desc->dir);
401	remove_proc_entry("affinity_hint", desc->dir);
402	remove_proc_entry("smp_affinity_list", desc->dir);
403	remove_proc_entry("node", desc->dir);
404# ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
405	remove_proc_entry("effective_affinity", desc->dir);
406	remove_proc_entry("effective_affinity_list", desc->dir);
407# endif
408#endif
409	remove_proc_entry("spurious", desc->dir);
410
 
411	sprintf(name, "%u", irq);
412	remove_proc_entry(name, root_irq_dir);
413}
414
415#undef MAX_NAMELEN
416
417void unregister_handler_proc(unsigned int irq, struct irqaction *action)
418{
419	proc_remove(action->dir);
420}
421
422static void register_default_affinity_proc(void)
423{
424#ifdef CONFIG_SMP
425	proc_create("irq/default_smp_affinity", 0644, NULL,
426		    &default_affinity_proc_ops);
427#endif
428}
429
430void init_irq_proc(void)
431{
432	unsigned int irq;
433	struct irq_desc *desc;
434
435	/* create /proc/irq */
436	root_irq_dir = proc_mkdir("irq", NULL);
437	if (!root_irq_dir)
438		return;
439
440	register_default_affinity_proc();
441
442	/*
443	 * Create entries for all existing IRQs.
444	 */
445	for_each_irq_desc(irq, desc)
 
 
 
446		register_irq_proc(irq, desc);
 
447}
448
449#ifdef CONFIG_GENERIC_IRQ_SHOW
450
451int __weak arch_show_interrupts(struct seq_file *p, int prec)
452{
453	return 0;
454}
455
456#ifndef ACTUAL_NR_IRQS
457# define ACTUAL_NR_IRQS nr_irqs
458#endif
459
460int show_interrupts(struct seq_file *p, void *v)
461{
462	static int prec;
463
464	unsigned long flags, any_count = 0;
465	int i = *(loff_t *) v, j;
466	struct irqaction *action;
467	struct irq_desc *desc;
468
469	if (i > ACTUAL_NR_IRQS)
470		return 0;
471
472	if (i == ACTUAL_NR_IRQS)
473		return arch_show_interrupts(p, prec);
474
475	/* print header and calculate the width of the first column */
476	if (i == 0) {
477		for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
478			j *= 10;
479
480		seq_printf(p, "%*s", prec + 8, "");
481		for_each_online_cpu(j)
482			seq_printf(p, "CPU%-8d", j);
483		seq_putc(p, '\n');
484	}
485
486	rcu_read_lock();
487	desc = irq_to_desc(i);
488	if (!desc || irq_settings_is_hidden(desc))
489		goto outsparse;
490
491	if (desc->kstat_irqs) {
492		for_each_online_cpu(j)
493			any_count |= data_race(*per_cpu_ptr(desc->kstat_irqs, j));
494	}
495
496	if ((!desc->action || irq_desc_is_chained(desc)) && !any_count)
497		goto outsparse;
498
499	seq_printf(p, "%*d: ", prec, i);
500	for_each_online_cpu(j)
501		seq_printf(p, "%10u ", desc->kstat_irqs ?
502					*per_cpu_ptr(desc->kstat_irqs, j) : 0);
503
504	raw_spin_lock_irqsave(&desc->lock, flags);
505	if (desc->irq_data.chip) {
506		if (desc->irq_data.chip->irq_print_chip)
507			desc->irq_data.chip->irq_print_chip(&desc->irq_data, p);
508		else if (desc->irq_data.chip->name)
509			seq_printf(p, " %8s", desc->irq_data.chip->name);
510		else
511			seq_printf(p, " %8s", "-");
512	} else {
513		seq_printf(p, " %8s", "None");
514	}
515	if (desc->irq_data.domain)
516		seq_printf(p, " %*lu", prec, desc->irq_data.hwirq);
517	else
518		seq_printf(p, " %*s", prec, "");
519#ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL
520	seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge");
521#endif
522	if (desc->name)
523		seq_printf(p, "-%-8s", desc->name);
524
525	action = desc->action;
526	if (action) {
527		seq_printf(p, "  %s", action->name);
528		while ((action = action->next) != NULL)
529			seq_printf(p, ", %s", action->name);
530	}
531
532	seq_putc(p, '\n');
 
533	raw_spin_unlock_irqrestore(&desc->lock, flags);
534outsparse:
535	rcu_read_unlock();
536	return 0;
537}
538#endif
v4.6
 
  1/*
  2 * linux/kernel/irq/proc.c
  3 *
  4 * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
  5 *
  6 * This file contains the /proc/irq/ handling code.
  7 */
  8
  9#include <linux/irq.h>
 10#include <linux/gfp.h>
 11#include <linux/proc_fs.h>
 12#include <linux/seq_file.h>
 13#include <linux/interrupt.h>
 14#include <linux/kernel_stat.h>
 15#include <linux/mutex.h>
 16
 17#include "internals.h"
 18
 19/*
 20 * Access rules:
 21 *
 22 * procfs protects read/write of /proc/irq/N/ files against a
 23 * concurrent free of the interrupt descriptor. remove_proc_entry()
 24 * immediately prevents new read/writes to happen and waits for
 25 * already running read/write functions to complete.
 26 *
 27 * We remove the proc entries first and then delete the interrupt
 28 * descriptor from the radix tree and free it. So it is guaranteed
 29 * that irq_to_desc(N) is valid as long as the read/writes are
 30 * permitted by procfs.
 31 *
 32 * The read from /proc/interrupts is a different problem because there
 33 * is no protection. So the lookup and the access to irqdesc
 34 * information must be protected by sparse_irq_lock.
 35 */
 36static struct proc_dir_entry *root_irq_dir;
 37
 38#ifdef CONFIG_SMP
 39
 40static int show_irq_affinity(int type, struct seq_file *m, void *v)
 
 
 
 
 
 
 
 41{
 42	struct irq_desc *desc = irq_to_desc((long)m->private);
 43	const struct cpumask *mask = desc->irq_common_data.affinity;
 44
 
 
 
 
 45#ifdef CONFIG_GENERIC_PENDING_IRQ
 46	if (irqd_is_setaffinity_pending(&desc->irq_data))
 47		mask = desc->pending_mask;
 
 
 
 
 
 
 
 48#endif
 49	if (type)
 
 
 
 
 
 
 50		seq_printf(m, "%*pbl\n", cpumask_pr_args(mask));
 51	else
 
 
 52		seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
 
 
 53	return 0;
 54}
 55
 56static int irq_affinity_hint_proc_show(struct seq_file *m, void *v)
 57{
 58	struct irq_desc *desc = irq_to_desc((long)m->private);
 59	unsigned long flags;
 60	cpumask_var_t mask;
 61
 62	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 63		return -ENOMEM;
 64
 65	raw_spin_lock_irqsave(&desc->lock, flags);
 66	if (desc->affinity_hint)
 67		cpumask_copy(mask, desc->affinity_hint);
 68	raw_spin_unlock_irqrestore(&desc->lock, flags);
 69
 70	seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
 71	free_cpumask_var(mask);
 72
 73	return 0;
 74}
 75
 76#ifndef is_affinity_mask_valid
 77#define is_affinity_mask_valid(val) 1
 78#endif
 79
 80int no_irq_affinity;
 81static int irq_affinity_proc_show(struct seq_file *m, void *v)
 82{
 83	return show_irq_affinity(0, m, v);
 84}
 85
 86static int irq_affinity_list_proc_show(struct seq_file *m, void *v)
 87{
 88	return show_irq_affinity(1, m, v);
 89}
 90
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 91
 92static ssize_t write_irq_affinity(int type, struct file *file,
 93		const char __user *buffer, size_t count, loff_t *pos)
 94{
 95	unsigned int irq = (int)(long)PDE_DATA(file_inode(file));
 96	cpumask_var_t new_value;
 97	int err;
 98
 99	if (!irq_can_set_affinity(irq) || no_irq_affinity)
100		return -EIO;
101
102	if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
103		return -ENOMEM;
104
105	if (type)
106		err = cpumask_parselist_user(buffer, count, new_value);
107	else
108		err = cpumask_parse_user(buffer, count, new_value);
109	if (err)
110		goto free_cpumask;
111
112	if (!is_affinity_mask_valid(new_value)) {
113		err = -EINVAL;
114		goto free_cpumask;
115	}
116
117	/*
118	 * Do not allow disabling IRQs completely - it's a too easy
119	 * way to make the system unusable accidentally :-) At least
120	 * one online CPU still has to be targeted.
121	 */
122	if (!cpumask_intersects(new_value, cpu_online_mask)) {
123		/* Special case for empty set - allow the architecture
124		   code to set default SMP affinity. */
125		err = irq_select_affinity_usr(irq, new_value) ? -EINVAL : count;
 
 
126	} else {
127		irq_set_affinity(irq, new_value);
128		err = count;
 
129	}
130
131free_cpumask:
132	free_cpumask_var(new_value);
133	return err;
134}
135
136static ssize_t irq_affinity_proc_write(struct file *file,
137		const char __user *buffer, size_t count, loff_t *pos)
138{
139	return write_irq_affinity(0, file, buffer, count, pos);
140}
141
142static ssize_t irq_affinity_list_proc_write(struct file *file,
143		const char __user *buffer, size_t count, loff_t *pos)
144{
145	return write_irq_affinity(1, file, buffer, count, pos);
146}
147
148static int irq_affinity_proc_open(struct inode *inode, struct file *file)
149{
150	return single_open(file, irq_affinity_proc_show, PDE_DATA(inode));
151}
152
153static int irq_affinity_list_proc_open(struct inode *inode, struct file *file)
154{
155	return single_open(file, irq_affinity_list_proc_show, PDE_DATA(inode));
156}
157
158static int irq_affinity_hint_proc_open(struct inode *inode, struct file *file)
159{
160	return single_open(file, irq_affinity_hint_proc_show, PDE_DATA(inode));
161}
 
 
 
162
163static const struct file_operations irq_affinity_proc_fops = {
164	.open		= irq_affinity_proc_open,
165	.read		= seq_read,
166	.llseek		= seq_lseek,
167	.release	= single_release,
168	.write		= irq_affinity_proc_write,
169};
170
171static const struct file_operations irq_affinity_hint_proc_fops = {
172	.open		= irq_affinity_hint_proc_open,
173	.read		= seq_read,
174	.llseek		= seq_lseek,
175	.release	= single_release,
176};
177
178static const struct file_operations irq_affinity_list_proc_fops = {
179	.open		= irq_affinity_list_proc_open,
180	.read		= seq_read,
181	.llseek		= seq_lseek,
182	.release	= single_release,
183	.write		= irq_affinity_list_proc_write,
184};
185
186static int default_affinity_show(struct seq_file *m, void *v)
187{
188	seq_printf(m, "%*pb\n", cpumask_pr_args(irq_default_affinity));
189	return 0;
190}
191
192static ssize_t default_affinity_write(struct file *file,
193		const char __user *buffer, size_t count, loff_t *ppos)
194{
195	cpumask_var_t new_value;
196	int err;
197
198	if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
199		return -ENOMEM;
200
201	err = cpumask_parse_user(buffer, count, new_value);
202	if (err)
203		goto out;
204
205	if (!is_affinity_mask_valid(new_value)) {
206		err = -EINVAL;
207		goto out;
208	}
209
210	/*
211	 * Do not allow disabling IRQs completely - it's a too easy
212	 * way to make the system unusable accidentally :-) At least
213	 * one online CPU still has to be targeted.
214	 */
215	if (!cpumask_intersects(new_value, cpu_online_mask)) {
216		err = -EINVAL;
217		goto out;
218	}
219
220	cpumask_copy(irq_default_affinity, new_value);
221	err = count;
222
223out:
224	free_cpumask_var(new_value);
225	return err;
226}
227
228static int default_affinity_open(struct inode *inode, struct file *file)
229{
230	return single_open(file, default_affinity_show, PDE_DATA(inode));
231}
232
233static const struct file_operations default_affinity_proc_fops = {
234	.open		= default_affinity_open,
235	.read		= seq_read,
236	.llseek		= seq_lseek,
237	.release	= single_release,
238	.write		= default_affinity_write,
239};
240
241static int irq_node_proc_show(struct seq_file *m, void *v)
242{
243	struct irq_desc *desc = irq_to_desc((long) m->private);
244
245	seq_printf(m, "%d\n", irq_desc_get_node(desc));
246	return 0;
247}
248
249static int irq_node_proc_open(struct inode *inode, struct file *file)
250{
251	return single_open(file, irq_node_proc_show, PDE_DATA(inode));
252}
253
254static const struct file_operations irq_node_proc_fops = {
255	.open		= irq_node_proc_open,
256	.read		= seq_read,
257	.llseek		= seq_lseek,
258	.release	= single_release,
259};
260#endif
261
262static int irq_spurious_proc_show(struct seq_file *m, void *v)
263{
264	struct irq_desc *desc = irq_to_desc((long) m->private);
265
266	seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n",
267		   desc->irq_count, desc->irqs_unhandled,
268		   jiffies_to_msecs(desc->last_unhandled));
269	return 0;
270}
271
272static int irq_spurious_proc_open(struct inode *inode, struct file *file)
273{
274	return single_open(file, irq_spurious_proc_show, PDE_DATA(inode));
275}
276
277static const struct file_operations irq_spurious_proc_fops = {
278	.open		= irq_spurious_proc_open,
279	.read		= seq_read,
280	.llseek		= seq_lseek,
281	.release	= single_release,
282};
283
284#define MAX_NAMELEN 128
285
286static int name_unique(unsigned int irq, struct irqaction *new_action)
287{
288	struct irq_desc *desc = irq_to_desc(irq);
289	struct irqaction *action;
290	unsigned long flags;
291	int ret = 1;
292
293	raw_spin_lock_irqsave(&desc->lock, flags);
294	for_each_action_of_desc(desc, action) {
295		if ((action != new_action) && action->name &&
296				!strcmp(new_action->name, action->name)) {
297			ret = 0;
298			break;
299		}
300	}
301	raw_spin_unlock_irqrestore(&desc->lock, flags);
302	return ret;
303}
304
305void register_handler_proc(unsigned int irq, struct irqaction *action)
306{
307	char name [MAX_NAMELEN];
308	struct irq_desc *desc = irq_to_desc(irq);
309
310	if (!desc->dir || action->dir || !action->name ||
311					!name_unique(irq, action))
312		return;
313
314	memset(name, 0, MAX_NAMELEN);
315	snprintf(name, MAX_NAMELEN, "%s", action->name);
316
317	/* create /proc/irq/1234/handler/ */
318	action->dir = proc_mkdir(name, desc->dir);
319}
320
321#undef MAX_NAMELEN
322
323#define MAX_NAMELEN 10
324
325void register_irq_proc(unsigned int irq, struct irq_desc *desc)
326{
327	static DEFINE_MUTEX(register_lock);
 
328	char name [MAX_NAMELEN];
329
330	if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip))
331		return;
332
333	/*
334	 * irq directories are registered only when a handler is
335	 * added, not when the descriptor is created, so multiple
336	 * tasks might try to register at the same time.
337	 */
338	mutex_lock(&register_lock);
339
340	if (desc->dir)
341		goto out_unlock;
342
343	memset(name, 0, MAX_NAMELEN);
344	sprintf(name, "%d", irq);
345
346	/* create /proc/irq/1234 */
347	desc->dir = proc_mkdir(name, root_irq_dir);
348	if (!desc->dir)
349		goto out_unlock;
350
351#ifdef CONFIG_SMP
352	/* create /proc/irq/<irq>/smp_affinity */
353	proc_create_data("smp_affinity", 0644, desc->dir,
354			 &irq_affinity_proc_fops, (void *)(long)irq);
355
356	/* create /proc/irq/<irq>/affinity_hint */
357	proc_create_data("affinity_hint", 0444, desc->dir,
358			 &irq_affinity_hint_proc_fops, (void *)(long)irq);
359
360	/* create /proc/irq/<irq>/smp_affinity_list */
361	proc_create_data("smp_affinity_list", 0644, desc->dir,
362			 &irq_affinity_list_proc_fops, (void *)(long)irq);
363
364	proc_create_data("node", 0444, desc->dir,
365			 &irq_node_proc_fops, (void *)(long)irq);
 
 
 
 
 
 
366#endif
367
368	proc_create_data("spurious", 0444, desc->dir,
369			 &irq_spurious_proc_fops, (void *)(long)irq);
370
371out_unlock:
372	mutex_unlock(&register_lock);
373}
374
375void unregister_irq_proc(unsigned int irq, struct irq_desc *desc)
376{
377	char name [MAX_NAMELEN];
378
379	if (!root_irq_dir || !desc->dir)
380		return;
381#ifdef CONFIG_SMP
382	remove_proc_entry("smp_affinity", desc->dir);
383	remove_proc_entry("affinity_hint", desc->dir);
384	remove_proc_entry("smp_affinity_list", desc->dir);
385	remove_proc_entry("node", desc->dir);
 
 
 
 
386#endif
387	remove_proc_entry("spurious", desc->dir);
388
389	memset(name, 0, MAX_NAMELEN);
390	sprintf(name, "%u", irq);
391	remove_proc_entry(name, root_irq_dir);
392}
393
394#undef MAX_NAMELEN
395
396void unregister_handler_proc(unsigned int irq, struct irqaction *action)
397{
398	proc_remove(action->dir);
399}
400
401static void register_default_affinity_proc(void)
402{
403#ifdef CONFIG_SMP
404	proc_create("irq/default_smp_affinity", 0644, NULL,
405		    &default_affinity_proc_fops);
406#endif
407}
408
409void init_irq_proc(void)
410{
411	unsigned int irq;
412	struct irq_desc *desc;
413
414	/* create /proc/irq */
415	root_irq_dir = proc_mkdir("irq", NULL);
416	if (!root_irq_dir)
417		return;
418
419	register_default_affinity_proc();
420
421	/*
422	 * Create entries for all existing IRQs.
423	 */
424	for_each_irq_desc(irq, desc) {
425		if (!desc)
426			continue;
427
428		register_irq_proc(irq, desc);
429	}
430}
431
432#ifdef CONFIG_GENERIC_IRQ_SHOW
433
434int __weak arch_show_interrupts(struct seq_file *p, int prec)
435{
436	return 0;
437}
438
439#ifndef ACTUAL_NR_IRQS
440# define ACTUAL_NR_IRQS nr_irqs
441#endif
442
443int show_interrupts(struct seq_file *p, void *v)
444{
445	static int prec;
446
447	unsigned long flags, any_count = 0;
448	int i = *(loff_t *) v, j;
449	struct irqaction *action;
450	struct irq_desc *desc;
451
452	if (i > ACTUAL_NR_IRQS)
453		return 0;
454
455	if (i == ACTUAL_NR_IRQS)
456		return arch_show_interrupts(p, prec);
457
458	/* print header and calculate the width of the first column */
459	if (i == 0) {
460		for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
461			j *= 10;
462
463		seq_printf(p, "%*s", prec + 8, "");
464		for_each_online_cpu(j)
465			seq_printf(p, "CPU%-8d", j);
466		seq_putc(p, '\n');
467	}
468
469	irq_lock_sparse();
470	desc = irq_to_desc(i);
471	if (!desc)
472		goto outsparse;
473
474	raw_spin_lock_irqsave(&desc->lock, flags);
475	for_each_online_cpu(j)
476		any_count |= kstat_irqs_cpu(i, j);
477	action = desc->action;
478	if ((!action || irq_desc_is_chained(desc)) && !any_count)
479		goto out;
 
480
481	seq_printf(p, "%*d: ", prec, i);
482	for_each_online_cpu(j)
483		seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 
484
 
485	if (desc->irq_data.chip) {
486		if (desc->irq_data.chip->irq_print_chip)
487			desc->irq_data.chip->irq_print_chip(&desc->irq_data, p);
488		else if (desc->irq_data.chip->name)
489			seq_printf(p, " %8s", desc->irq_data.chip->name);
490		else
491			seq_printf(p, " %8s", "-");
492	} else {
493		seq_printf(p, " %8s", "None");
494	}
495	if (desc->irq_data.domain)
496		seq_printf(p, " %*d", prec, (int) desc->irq_data.hwirq);
 
 
497#ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL
498	seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge");
499#endif
500	if (desc->name)
501		seq_printf(p, "-%-8s", desc->name);
502
 
503	if (action) {
504		seq_printf(p, "  %s", action->name);
505		while ((action = action->next) != NULL)
506			seq_printf(p, ", %s", action->name);
507	}
508
509	seq_putc(p, '\n');
510out:
511	raw_spin_unlock_irqrestore(&desc->lock, flags);
512outsparse:
513	irq_unlock_sparse();
514	return 0;
515}
516#endif