#ifndef __LINUX_CPU_RMAP_H
#define __LINUX_CPU_RMAP_H

/*
* cpu_rmap.c: CPU affinity reverse-map support
* Copyright 2011 Solarflare Communications Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation, incorporated herein by reference.
*/

#include <linux/cpumask.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/kref.h>

/**
* struct cpu_rmap - CPU affinity reverse-map
* @refcount: kref for object
* @size: Number of objects to be reverse-mapped
* @used: Number of objects added
* @obj: Pointer to array of object pointers
* @near: For each CPU, the index and distance to the nearest object,
* based on affinity masks
*/
struct cpu_rmap {
struct kref refcount;
u16 size, used;
void **obj;
struct {
u16 index;
u16 dist;
} near[0];
};
#define CPU_RMAP_DIST_INF 0xffff

extern struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags);
extern int cpu_rmap_put(struct cpu_rmap *rmap);

extern int cpu_rmap_add(struct cpu_rmap *rmap, void *obj);
extern int cpu_rmap_update(struct cpu_rmap *rmap, u16 index,
const struct cpumask *affinity);

static inline u16 cpu_rmap_lookup_index(struct cpu_rmap *rmap, unsigned int cpu)
{
return rmap->near[cpu].index;
}

static inline void *cpu_rmap_lookup_obj(struct cpu_rmap *rmap, unsigned int cpu)
{
return rmap->obj[rmap->near[cpu].index];
}

/**
* alloc_irq_cpu_rmap - allocate CPU affinity reverse-map for IRQs
* @size: Number of objects to be mapped
*
* Must be called in process context.
*/
static inline struct cpu_rmap *alloc_irq_cpu_rmap(unsigned int size)
{
return alloc_cpu_rmap(size, GFP_KERNEL);
}
extern void free_irq_cpu_rmap(struct cpu_rmap *rmap);

extern int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq);

#endif /* __LINUX_CPU_RMAP_H */