1#ifndef _LINUX_PRIO_HEAP_H 2#define _LINUX_PRIO_HEAP_H 3 4/* 5 * Simple insertion-only static-sized priority heap containing 6 * pointers, based on CLR, chapter 7 7 */ 8 9#include <linux/gfp.h> 10 11/** 12 * struct ptr_heap - simple static-sized priority heap 13 * @ptrs - pointer to data area 14 * @max - max number of elements that can be stored in @ptrs 15 * @size - current number of valid elements in @ptrs (in the range 0..@size-1 16 * @gt: comparison operator, which should implement "greater than" 17 */ 18struct ptr_heap { 19 void **ptrs; 20 int max; 21 int size; 22 int (*gt)(void *, void *); 23}; 24 25/** 26 * heap_init - initialize an empty heap with a given memory size 27 * @heap: the heap structure to be initialized 28 * @size: amount of memory to use in bytes 29 * @gfp_mask: mask to pass to kmalloc() 30 * @gt: comparison operator, which should implement "greater than" 31 */ 32extern int heap_init(struct ptr_heap *heap, size_t size, gfp_t gfp_mask, 33 int (*gt)(void *, void *)); 34 35/** 36 * heap_free - release a heap's storage 37 * @heap: the heap structure whose data should be released 38 */ 39void heap_free(struct ptr_heap *heap); 40 41/** 42 * heap_insert - insert a value into the heap and return any overflowed value 43 * @heap: the heap to be operated on 44 * @p: the pointer to be inserted 45 * 46 * Attempts to insert the given value into the priority heap. If the 47 * heap is full prior to the insertion, then the resulting heap will 48 * consist of the smallest @max elements of the original heap and the 49 * new element; the greatest element will be removed from the heap and 50 * returned. Note that the returned element will be the new element 51 * (i.e. no change to the heap) if the new element is greater than all 52 * elements currently in the heap. 53 */ 54extern void *heap_insert(struct ptr_heap *heap, void *p); 55 56 57 58#endif /* _LINUX_PRIO_HEAP_H */ 59