[mirror_ubuntu-zesty-kernel.git] / kernel / irq / irqdesc.c

/*
 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
 *
 * This file contains the interrupt descriptor management code
 *
 * Detailed information is available in Documentation/DocBook/genericirq
 *
 */
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/radix-tree.h>
#include <linux/bitmap.h>

#include "internals.h"

/*
 * lockdep: we want to handle all irq_desc locks as a single lock-class:
 */
struct lock_class_key irq_desc_lock_class;

#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
static void __init init_irq_default_affinity(void)
{
	alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
	cpumask_setall(irq_default_affinity);
}
#else
static void __init init_irq_default_affinity(void)
{
}
#endif

#ifdef CONFIG_SMP
static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
{
	if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
		return -ENOMEM;

#ifdef CONFIG_GENERIC_PENDING_IRQ
	if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
		free_cpumask_var(desc->irq_data.affinity);
		return -ENOMEM;
	}
#endif
	return 0;
}

static void desc_smp_init(struct irq_desc *desc, int node)
{
	desc->node = node;
	cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
}

#else
static inline int
alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
static inline void desc_smp_init(struct irq_desc *desc, int node) { }
#endif

static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node)
{
	desc->irq_data.irq = irq;
	desc->irq_data.chip = &no_irq_chip;
	desc->irq_data.chip_data = NULL;
	desc->irq_data.handler_data = NULL;
	desc->irq_data.msi_desc = NULL;
	desc->status = IRQ_DEFAULT_INIT_FLAGS;
	desc->handle_irq = handle_bad_irq;
	desc->depth = 1;
	desc->name = NULL;
	memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
	desc_smp_init(desc, node);
}

int nr_irqs = NR_IRQS;
EXPORT_SYMBOL_GPL(nr_irqs);

DEFINE_RAW_SPINLOCK(sparse_irq_lock);
static DECLARE_BITMAP(allocated_irqs, NR_IRQS);

#ifdef CONFIG_SPARSE_IRQ

static struct irq_desc irq_desc_init = {
	.status		= IRQ_DEFAULT_INIT_FLAGS,
	.handle_irq	= handle_bad_irq,
	.depth		= 1,
	.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
};

void __ref init_kstat_irqs(struct irq_desc *desc, int node, int nr)
{
	void *ptr;

	ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs),
			   GFP_ATOMIC, node);

	/*
	 * don't overwite if can not get new one
	 * init_copy_kstat_irqs() could still use old one
	 */
	if (ptr) {
		printk(KERN_DEBUG "  alloc kstat_irqs on node %d\n", node);
		desc->kstat_irqs = ptr;
	}
}

static void init_one_irq_desc(int irq, struct irq_desc *desc, int node)
{
	memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));

	raw_spin_lock_init(&desc->lock);
	desc->irq_data.irq = irq;
#ifdef CONFIG_SMP
	desc->irq_data.node = node;
#endif
	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
	init_kstat_irqs(desc, node, nr_cpu_ids);
	if (!desc->kstat_irqs) {
		printk(KERN_ERR "can not alloc kstat_irqs\n");
		BUG_ON(1);
	}
	if (!alloc_desc_masks(desc, node, false)) {
		printk(KERN_ERR "can not alloc irq_desc cpumasks\n");
		BUG_ON(1);
	}
	init_desc_masks(desc);
	arch_init_chip_data(desc, node);
}

static RADIX_TREE(irq_desc_tree, GFP_ATOMIC);

static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
{
	radix_tree_insert(&irq_desc_tree, irq, desc);
}

struct irq_desc *irq_to_desc(unsigned int irq)
{
	return radix_tree_lookup(&irq_desc_tree, irq);
}

void replace_irq_desc(unsigned int irq, struct irq_desc *desc)
{
	void **ptr;

	ptr = radix_tree_lookup_slot(&irq_desc_tree, irq);
	if (ptr)
		radix_tree_replace_slot(ptr, desc);
}

static void delete_irq_desc(unsigned int irq)
{
	radix_tree_delete(&irq_desc_tree, irq);
}

#ifdef CONFIG_SMP
static void free_masks(struct irq_desc *desc)
{
#ifdef CONFIG_GENERIC_PENDING_IRQ
	free_cpumask_var(desc->pending_mask);
#endif
	free_cpumask_var(desc->affinity);
}
#else
static inline void free_masks(struct irq_desc *desc) { }
#endif

static struct irq_desc *alloc_desc(int irq, int node)
{
	struct irq_desc *desc;
	gfp_t gfp = GFP_KERNEL;

	desc = kzalloc_node(sizeof(*desc), gfp, node);
	if (!desc)
		return NULL;
	/* allocate based on nr_cpu_ids */
	desc->kstat_irqs = kzalloc_node(nr_cpu_ids * sizeof(*desc->kstat_irqs),
					 gfp, node);
	if (!desc->kstat_irqs)
		goto err_desc;

	if (alloc_masks(desc, gfp, node))
		goto err_kstat;

	raw_spin_lock_init(&desc->lock);
	lockdep_set_class(&desc->lock, &irq_desc_lock_class);

	desc_set_defaults(irq, desc, node);

	return desc;

err_kstat:
	kfree(desc->kstat_irqs);
err_desc:
	kfree(desc);
	return NULL;
}

static void free_desc(unsigned int irq)
{
	struct irq_desc *desc = irq_to_desc(irq);
	unsigned long flags;

	unregister_irq_proc(irq, desc);

	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	delete_irq_desc(irq);
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);

	free_masks(desc);
	kfree(desc->kstat_irqs);
	kfree(desc);
}

static int alloc_descs(unsigned int start, unsigned int cnt, int node)
{
	struct irq_desc *desc;
	unsigned long flags;
	int i;

	for (i = 0; i < cnt; i++) {
		desc = alloc_desc(start + i, node);
		if (!desc)
			goto err;
		raw_spin_lock_irqsave(&sparse_irq_lock, flags);
		irq_insert_desc(start + i, desc);
		raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	}
	return start;

err:
	for (i--; i >= 0; i--)
		free_desc(start + i);

	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	bitmap_clear(allocated_irqs, start, cnt);
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	return -ENOMEM;
}

static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
	[0 ... NR_IRQS_LEGACY-1] = {
		.status		= IRQ_DEFAULT_INIT_FLAGS,
		.handle_irq	= handle_bad_irq,
		.depth		= 1,
		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
	}
};

static unsigned int *kstat_irqs_legacy;

int __init early_irq_init(void)
{
	struct irq_desc *desc;
	int legacy_count;
	int node;
	int i;

	init_irq_default_affinity();

	 /* initialize nr_irqs based on nr_cpu_ids */
	arch_probe_nr_irqs();
	printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d\n", NR_IRQS, nr_irqs);

	desc = irq_desc_legacy;
	legacy_count = ARRAY_SIZE(irq_desc_legacy);
	node = first_online_node;

	/* allocate based on nr_cpu_ids */
	kstat_irqs_legacy = kzalloc_node(NR_IRQS_LEGACY * nr_cpu_ids *
					  sizeof(int), GFP_NOWAIT, node);

	irq_desc_init.irq_data.chip = &no_irq_chip;

	for (i = 0; i < legacy_count; i++) {
		desc[i].irq_data.irq = i;
		desc[i].irq_data.chip = &no_irq_chip;
#ifdef CONFIG_SMP
		desc[i].irq_data.node = node;
#endif
		desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids;
		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
		alloc_desc_masks(&desc[i], node, true);
		init_desc_masks(&desc[i]);
		irq_insert_desc(i, &desc[i]);
	}

	return arch_early_irq_init();
}

struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
{
	struct irq_desc *desc;
	unsigned long flags;

	if (irq >= nr_irqs) {
		WARN(1, "irq (%d) >= nr_irqs (%d) in irq_to_desc_alloc\n",
			irq, nr_irqs);
		return NULL;
	}

	desc = irq_to_desc(irq);
	if (desc)
		return desc;

	raw_spin_lock_irqsave(&sparse_irq_lock, flags);

	/* We have to check it to avoid races with another CPU */
	desc = irq_to_desc(irq);
	if (desc)
		goto out_unlock;

	desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);

	printk(KERN_DEBUG "  alloc irq_desc for %d on node %d\n", irq, node);
	if (!desc) {
		printk(KERN_ERR "can not alloc irq_desc\n");
		BUG_ON(1);
	}
	init_one_irq_desc(irq, desc, node);

	irq_insert_desc(irq, desc);

out_unlock:
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);

	return desc;
}

#else /* !CONFIG_SPARSE_IRQ */

struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
	[0 ... NR_IRQS-1] = {
		.status		= IRQ_DEFAULT_INIT_FLAGS,
		.handle_irq	= handle_bad_irq,
		.depth		= 1,
		.lock		= __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
	}
};

static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS];
int __init early_irq_init(void)
{
	struct irq_desc *desc;
	int count;
	int i;

	init_irq_default_affinity();

	printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);

	desc = irq_desc;
	count = ARRAY_SIZE(irq_desc);

	for (i = 0; i < count; i++) {
		desc[i].irq_data.irq = i;
		desc[i].irq_data.chip = &no_irq_chip;
		alloc_desc_masks(&desc[i], 0, true);
		init_desc_masks(&desc[i]);
		desc[i].kstat_irqs = kstat_irqs_all[i];
		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
	}
	return arch_early_irq_init();
}

struct irq_desc *irq_to_desc(unsigned int irq)
{
	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
}

struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node)
{
	return irq_to_desc(irq);
}

#ifdef CONFIG_SMP
static inline int desc_node(struct irq_desc *desc)
{
	return desc->irq_data.node;
}
#else
static inline int desc_node(struct irq_desc *desc) { return 0; }
#endif

static void free_desc(unsigned int irq)
{
	struct irq_desc *desc = irq_to_desc(irq);
	unsigned long flags;

	raw_spin_lock_irqsave(&desc->lock, flags);
	desc_set_defaults(irq, desc, desc_node(desc));
	raw_spin_unlock_irqrestore(&desc->lock, flags);
}

static inline int alloc_descs(unsigned int start, unsigned int cnt, int node)
{
	return start;
}
#endif /* !CONFIG_SPARSE_IRQ */

/* Dynamic interrupt handling */

/**
 * irq_free_descs - free irq descriptors
 * @from:	Start of descriptor range
 * @cnt:	Number of consecutive irqs to free
 */
void irq_free_descs(unsigned int from, unsigned int cnt)
{
	unsigned long flags;
	int i;

	if (from >= nr_irqs || (from + cnt) > nr_irqs)
		return;

	for (i = 0; i < cnt; i++)
		free_desc(from + i);

	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	bitmap_clear(allocated_irqs, from, cnt);
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
}

/**
 * irq_alloc_descs - allocate and initialize a range of irq descriptors
 * @irq:	Allocate for specific irq number if irq >= 0
 * @from:	Start the search from this irq number
 * @cnt:	Number of consecutive irqs to allocate.
 * @node:	Preferred node on which the irq descriptor should be allocated
 *
 * Returns the first irq number or error code
 */
int __ref
irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node)
{
	unsigned long flags;
	int start, ret;

	if (!cnt)
		return -EINVAL;

	raw_spin_lock_irqsave(&sparse_irq_lock, flags);

	start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
	ret = -EEXIST;
	if (irq >=0 && start != irq)
		goto err;

	ret = -ENOMEM;
	if (start >= nr_irqs)
		goto err;

	bitmap_set(allocated_irqs, start, cnt);
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	return alloc_descs(start, cnt, node);

err:
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	return ret;
}

/**
 * irq_reserve_irqs - mark irqs allocated
 * @from:	mark from irq number
 * @cnt:	number of irqs to mark
 *
 * Returns 0 on success or an appropriate error code
 */
int irq_reserve_irqs(unsigned int from, unsigned int cnt)
{
	unsigned long flags;
	unsigned int start;
	int ret = 0;

	if (!cnt || (from + cnt) > nr_irqs)
		return -EINVAL;

	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
	if (start == from)
		bitmap_set(allocated_irqs, start, cnt);
	else
		ret = -EEXIST;
	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	return ret;
}

/**
 * irq_get_next_irq - get next allocated irq number
 * @offset:	where to start the search
 *
 * Returns next irq number after offset or nr_irqs if none is found.
 */
unsigned int irq_get_next_irq(unsigned int offset)
{
	return find_next_bit(allocated_irqs, nr_irqs, offset);
}

/* Statistics access */
void clear_kstat_irqs(struct irq_desc *desc)
{
	memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
}

unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
{
	struct irq_desc *desc = irq_to_desc(irq);
	return desc ? desc->kstat_irqs[cpu] : 0;
}
Commit	Line	Data
3795de23 TG	1	/*
	2	* Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
	3	* Copyright (C) 2005-2006, Thomas Gleixner, Russell King
	4	*
	5	* This file contains the interrupt descriptor management code
	6	*
	7	* Detailed information is available in Documentation/DocBook/genericirq
	8	*
	9	*/
	10	#include <linux/irq.h>
	11	#include <linux/slab.h>
	12	#include <linux/module.h>
	13	#include <linux/interrupt.h>
	14	#include <linux/kernel_stat.h>
	15	#include <linux/radix-tree.h>
1f5a5b87	16	#include <linux/bitmap.h>
3795de23 TG	17
	18	#include "internals.h"
	19
	20	/*
	21	* lockdep: we want to handle all irq_desc locks as a single lock-class:
	22	*/
	23	struct lock_class_key irq_desc_lock_class;
	24
	25	#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
	26	static void __init init_irq_default_affinity(void)
	27	{
	28	alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
	29	cpumask_setall(irq_default_affinity);
	30	}
	31	#else
	32	static void __init init_irq_default_affinity(void)
	33	{
	34	}
	35	#endif
	36
1f5a5b87 TG	37	#ifdef CONFIG_SMP
	38	static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
	39	{
	40	if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
	41	return -ENOMEM;
	42
	43	#ifdef CONFIG_GENERIC_PENDING_IRQ
	44	if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
	45	free_cpumask_var(desc->irq_data.affinity);
	46	return -ENOMEM;
	47	}
	48	#endif
	49	return 0;
	50	}
	51
	52	static void desc_smp_init(struct irq_desc *desc, int node)
	53	{
	54	desc->node = node;
	55	cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
	56	}
	57
	58	#else
	59	static inline int
	60	alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
	61	static inline void desc_smp_init(struct irq_desc *desc, int node) { }
	62	#endif
	63
	64	static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node)
	65	{
	66	desc->irq_data.irq = irq;
	67	desc->irq_data.chip = &no_irq_chip;
	68	desc->irq_data.chip_data = NULL;
	69	desc->irq_data.handler_data = NULL;
	70	desc->irq_data.msi_desc = NULL;
	71	desc->status = IRQ_DEFAULT_INIT_FLAGS;
	72	desc->handle_irq = handle_bad_irq;
	73	desc->depth = 1;
	74	desc->name = NULL;
	75	memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
	76	desc_smp_init(desc, node);
	77	}
	78
3795de23 TG	79	int nr_irqs = NR_IRQS;
	80	EXPORT_SYMBOL_GPL(nr_irqs);
	81
1f5a5b87 TG	82	DEFINE_RAW_SPINLOCK(sparse_irq_lock);
	83	static DECLARE_BITMAP(allocated_irqs, NR_IRQS);
	84
3795de23 TG	85	#ifdef CONFIG_SPARSE_IRQ
	86
	87	static struct irq_desc irq_desc_init = {
1318a481	88	.status = IRQ_DEFAULT_INIT_FLAGS,
3795de23 TG	89	.handle_irq = handle_bad_irq,
	90	.depth = 1,
	91	.lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
	92	};
	93
	94	void __ref init_kstat_irqs(struct irq_desc *desc, int node, int nr)
	95	{
	96	void *ptr;
	97
	98	ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs),
	99	GFP_ATOMIC, node);
	100
	101	/*
	102	* don't overwite if can not get new one
	103	* init_copy_kstat_irqs() could still use old one
	104	*/
	105	if (ptr) {
	106	printk(KERN_DEBUG " alloc kstat_irqs on node %d\n", node);
	107	desc->kstat_irqs = ptr;
	108	}
	109	}
	110
	111	static void init_one_irq_desc(int irq, struct irq_desc *desc, int node)
	112	{
	113	memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
	114
	115	raw_spin_lock_init(&desc->lock);
	116	desc->irq_data.irq = irq;
	117	#ifdef CONFIG_SMP
	118	desc->irq_data.node = node;
	119	#endif
	120	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
	121	init_kstat_irqs(desc, node, nr_cpu_ids);
	122	if (!desc->kstat_irqs) {
	123	printk(KERN_ERR "can not alloc kstat_irqs\n");
	124	BUG_ON(1);
	125	}
	126	if (!alloc_desc_masks(desc, node, false)) {
	127	printk(KERN_ERR "can not alloc irq_desc cpumasks\n");
	128	BUG_ON(1);
	129	}
	130	init_desc_masks(desc);
	131	arch_init_chip_data(desc, node);
	132	}
	133
3795de23 TG	134	static RADIX_TREE(irq_desc_tree, GFP_ATOMIC);
3795de23 TG	135
1f5a5b87	136	static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
3795de23 TG	137	{
	138	radix_tree_insert(&irq_desc_tree, irq, desc);
	139	}
	140
	141	struct irq_desc *irq_to_desc(unsigned int irq)
	142	{
	143	return radix_tree_lookup(&irq_desc_tree, irq);
	144	}
	145
	146	void replace_irq_desc(unsigned int irq, struct irq_desc *desc)
	147	{
	148	void **ptr;
	149
	150	ptr = radix_tree_lookup_slot(&irq_desc_tree, irq);
	151	if (ptr)
	152	radix_tree_replace_slot(ptr, desc);
	153	}
	154
1f5a5b87 TG	155	static void delete_irq_desc(unsigned int irq)
	156	{
	157	radix_tree_delete(&irq_desc_tree, irq);
	158	}
	159
	160	#ifdef CONFIG_SMP
	161	static void free_masks(struct irq_desc *desc)
	162	{
	163	#ifdef CONFIG_GENERIC_PENDING_IRQ
	164	free_cpumask_var(desc->pending_mask);
	165	#endif
	166	free_cpumask_var(desc->affinity);
	167	}
	168	#else
	169	static inline void free_masks(struct irq_desc *desc) { }
	170	#endif
	171
	172	static struct irq_desc *alloc_desc(int irq, int node)
	173	{
	174	struct irq_desc *desc;
	175	gfp_t gfp = GFP_KERNEL;
	176
	177	desc = kzalloc_node(sizeof(*desc), gfp, node);
	178	if (!desc)
	179	return NULL;
	180	/* allocate based on nr_cpu_ids */
	181	desc->kstat_irqs = kzalloc_node(nr_cpu_ids * sizeof(*desc->kstat_irqs),
	182	gfp, node);
	183	if (!desc->kstat_irqs)
	184	goto err_desc;
	185
	186	if (alloc_masks(desc, gfp, node))
	187	goto err_kstat;
	188
	189	raw_spin_lock_init(&desc->lock);
	190	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
	191
	192	desc_set_defaults(irq, desc, node);
	193
	194	return desc;
	195
	196	err_kstat:
	197	kfree(desc->kstat_irqs);
	198	err_desc:
	199	kfree(desc);
	200	return NULL;
	201	}
	202
	203	static void free_desc(unsigned int irq)
	204	{
	205	struct irq_desc *desc = irq_to_desc(irq);
	206	unsigned long flags;
	207
13bfe99e TG	208	unregister_irq_proc(irq, desc);
13bfe99e TG	209
1f5a5b87 TG	210	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	211	delete_irq_desc(irq);
	212	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	213
	214	free_masks(desc);
	215	kfree(desc->kstat_irqs);
	216	kfree(desc);
	217	}
	218
	219	static int alloc_descs(unsigned int start, unsigned int cnt, int node)
	220	{
	221	struct irq_desc *desc;
	222	unsigned long flags;
	223	int i;
	224
	225	for (i = 0; i < cnt; i++) {
	226	desc = alloc_desc(start + i, node);
	227	if (!desc)
	228	goto err;
	229	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	230	irq_insert_desc(start + i, desc);
	231	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	232	}
	233	return start;
	234
	235	err:
	236	for (i--; i >= 0; i--)
	237	free_desc(start + i);
	238
	239	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	240	bitmap_clear(allocated_irqs, start, cnt);
	241	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	242	return -ENOMEM;
	243	}
	244
3795de23 TG	245	static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
3795de23 TG	246	[0 ... NR_IRQS_LEGACY-1] = {
1318a481	247	.status = IRQ_DEFAULT_INIT_FLAGS,
3795de23 TG	248	.handle_irq = handle_bad_irq,
	249	.depth = 1,
	250	.lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
	251	}
	252	};
	253
	254	static unsigned int *kstat_irqs_legacy;
	255
	256	int __init early_irq_init(void)
	257	{
	258	struct irq_desc *desc;
	259	int legacy_count;
	260	int node;
	261	int i;
	262
	263	init_irq_default_affinity();
	264
	265	/* initialize nr_irqs based on nr_cpu_ids */
	266	arch_probe_nr_irqs();
	267	printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d\n", NR_IRQS, nr_irqs);
	268
	269	desc = irq_desc_legacy;
	270	legacy_count = ARRAY_SIZE(irq_desc_legacy);
	271	node = first_online_node;
	272
	273	/* allocate based on nr_cpu_ids */
	274	kstat_irqs_legacy = kzalloc_node(NR_IRQS_LEGACY * nr_cpu_ids *
	275	sizeof(int), GFP_NOWAIT, node);
	276
	277	irq_desc_init.irq_data.chip = &no_irq_chip;
	278
	279	for (i = 0; i < legacy_count; i++) {
	280	desc[i].irq_data.irq = i;
	281	desc[i].irq_data.chip = &no_irq_chip;
	282	#ifdef CONFIG_SMP
	283	desc[i].irq_data.node = node;
	284	#endif
	285	desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids;
	286	lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
	287	alloc_desc_masks(&desc[i], node, true);
	288	init_desc_masks(&desc[i]);
1f5a5b87	289	irq_insert_desc(i, &desc[i]);
3795de23 TG	290	}
	291
	292	return arch_early_irq_init();
	293	}
	294
	295	struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
	296	{
	297	struct irq_desc *desc;
	298	unsigned long flags;
	299
	300	if (irq >= nr_irqs) {
	301	WARN(1, "irq (%d) >= nr_irqs (%d) in irq_to_desc_alloc\n",
	302	irq, nr_irqs);
	303	return NULL;
	304	}
	305
	306	desc = irq_to_desc(irq);
	307	if (desc)
	308	return desc;
	309
	310	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	311
	312	/* We have to check it to avoid races with another CPU */
	313	desc = irq_to_desc(irq);
	314	if (desc)
	315	goto out_unlock;
	316
	317	desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
	318
	319	printk(KERN_DEBUG " alloc irq_desc for %d on node %d\n", irq, node);
	320	if (!desc) {
	321	printk(KERN_ERR "can not alloc irq_desc\n");
	322	BUG_ON(1);
	323	}
	324	init_one_irq_desc(irq, desc, node);
	325
1f5a5b87	326	irq_insert_desc(irq, desc);
3795de23 TG	327
	328	out_unlock:
	329	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	330
	331	return desc;
	332	}
	333
	334	#else /* !CONFIG_SPARSE_IRQ */
	335
	336	struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
	337	[0 ... NR_IRQS-1] = {
1318a481	338	.status = IRQ_DEFAULT_INIT_FLAGS,
3795de23 TG	339	.handle_irq = handle_bad_irq,
	340	.depth = 1,
	341	.lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
	342	}
	343	};
	344
	345	static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS];
	346	int __init early_irq_init(void)
	347	{
	348	struct irq_desc *desc;
	349	int count;
	350	int i;
	351
	352	init_irq_default_affinity();
	353
	354	printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
	355
	356	desc = irq_desc;
	357	count = ARRAY_SIZE(irq_desc);
	358
	359	for (i = 0; i < count; i++) {
	360	desc[i].irq_data.irq = i;
	361	desc[i].irq_data.chip = &no_irq_chip;
	362	alloc_desc_masks(&desc[i], 0, true);
	363	init_desc_masks(&desc[i]);
	364	desc[i].kstat_irqs = kstat_irqs_all[i];
154cd387	365	lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
3795de23 TG	366	}
	367	return arch_early_irq_init();
	368	}
	369
	370	struct irq_desc *irq_to_desc(unsigned int irq)
	371	{
	372	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
	373	}
	374
	375	struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node)
	376	{
	377	return irq_to_desc(irq);
	378	}
1f5a5b87 TG	379
	380	#ifdef CONFIG_SMP
	381	static inline int desc_node(struct irq_desc *desc)
	382	{
	383	return desc->irq_data.node;
	384	}
	385	#else
	386	static inline int desc_node(struct irq_desc *desc) { return 0; }
	387	#endif
	388
	389	static void free_desc(unsigned int irq)
	390	{
	391	struct irq_desc *desc = irq_to_desc(irq);
	392	unsigned long flags;
	393
	394	raw_spin_lock_irqsave(&desc->lock, flags);
	395	desc_set_defaults(irq, desc, desc_node(desc));
	396	raw_spin_unlock_irqrestore(&desc->lock, flags);
	397	}
	398
	399	static inline int alloc_descs(unsigned int start, unsigned int cnt, int node)
	400	{
	401	return start;
	402	}
3795de23 TG	403	#endif /* !CONFIG_SPARSE_IRQ */
3795de23 TG	404
1f5a5b87 TG	405	/* Dynamic interrupt handling */
	406
	407	/**
	408	* irq_free_descs - free irq descriptors
	409	* @from: Start of descriptor range
	410	* @cnt: Number of consecutive irqs to free
	411	*/
	412	void irq_free_descs(unsigned int from, unsigned int cnt)
	413	{
	414	unsigned long flags;
	415	int i;
	416
	417	if (from >= nr_irqs \|\| (from + cnt) > nr_irqs)
	418	return;
	419
	420	for (i = 0; i < cnt; i++)
	421	free_desc(from + i);
	422
	423	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	424	bitmap_clear(allocated_irqs, from, cnt);
	425	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	426	}
	427
	428	/**
	429	* irq_alloc_descs - allocate and initialize a range of irq descriptors
	430	* @irq: Allocate for specific irq number if irq >= 0
	431	* @from: Start the search from this irq number
	432	* @cnt: Number of consecutive irqs to allocate.
	433	* @node: Preferred node on which the irq descriptor should be allocated
	434	*
	435	* Returns the first irq number or error code
	436	*/
	437	int __ref
	438	irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node)
	439	{
	440	unsigned long flags;
	441	int start, ret;
	442
	443	if (!cnt)
	444	return -EINVAL;
	445
	446	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	447
	448	start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
	449	ret = -EEXIST;
	450	if (irq >=0 && start != irq)
	451	goto err;
	452
	453	ret = -ENOMEM;
	454	if (start >= nr_irqs)
	455	goto err;
	456
	457	bitmap_set(allocated_irqs, start, cnt);
	458	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	459	return alloc_descs(start, cnt, node);
	460
	461	err:
	462	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	463	return ret;
	464	}
	465
06f6c339 TG	466	/**
	467	* irq_reserve_irqs - mark irqs allocated
	468	* @from: mark from irq number
	469	* @cnt: number of irqs to mark
	470	*
	471	* Returns 0 on success or an appropriate error code
	472	*/
	473	int irq_reserve_irqs(unsigned int from, unsigned int cnt)
	474	{
	475	unsigned long flags;
	476	unsigned int start;
	477	int ret = 0;
	478
	479	if (!cnt \|\| (from + cnt) > nr_irqs)
	480	return -EINVAL;
	481
	482	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
	483	start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
	484	if (start == from)
	485	bitmap_set(allocated_irqs, start, cnt);
	486	else
	487	ret = -EEXIST;
	488	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
	489	return ret;
	490	}
	491
a98d24b7 TG	492	/**
	493	* irq_get_next_irq - get next allocated irq number
	494	* @offset: where to start the search
	495	*
	496	* Returns next irq number after offset or nr_irqs if none is found.
	497	*/
	498	unsigned int irq_get_next_irq(unsigned int offset)
	499	{
	500	return find_next_bit(allocated_irqs, nr_irqs, offset);
	501	}
	502
1f5a5b87	503	/* Statistics access */
3795de23 TG	504	void clear_kstat_irqs(struct irq_desc *desc)
	505	{
	506	memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
	507	}
	508
3795de23 TG	509	unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
	510	{
	511	struct irq_desc *desc = irq_to_desc(irq);
	512	return desc ? desc->kstat_irqs[cpu] : 0;
	513	}