[linux-2.6-block.git] / fs / btrfs / ulist.h

/*
 * Copyright (C) 2011 STRATO AG
 * written by Arne Jansen <sensille@gmx.net>
 * Distributed under the GNU GPL license version 2.
 *
 */

#ifndef __ULIST__
#define __ULIST__

#include <linux/list.h>
#include <linux/rbtree.h>

/*
 * ulist is a generic data structure to hold a collection of unique u64
 * values. The only operations it supports is adding to the list and
 * enumerating it.
 * It is possible to store an auxiliary value along with the key.
 *
 */
struct ulist_iterator {
#ifdef CONFIG_BTRFS_DEBUG
	int i;
#endif
	struct list_head *cur_list;  /* hint to start search */
};

/*
 * element of the list
 */
struct ulist_node {
	u64 val;		/* value to store */
	u64 aux;		/* auxiliary value saved along with the val */

#ifdef CONFIG_BTRFS_DEBUG
	int seqnum;		/* sequence number this node is added */
#endif

	struct list_head list;  /* used to link node */
	struct rb_node rb_node;	/* used to speed up search */
};

struct ulist {
	/*
	 * number of elements stored in list
	 */
	unsigned long nnodes;

	struct list_head nodes;
	struct rb_root root;
};

void ulist_init(struct ulist *ulist);
void ulist_reinit(struct ulist *ulist);
struct ulist *ulist_alloc(gfp_t gfp_mask);
void ulist_free(struct ulist *ulist);
int ulist_add(struct ulist *ulist, u64 val, u64 aux, gfp_t gfp_mask);
int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux,
		    u64 *old_aux, gfp_t gfp_mask);
int ulist_del(struct ulist *ulist, u64 val, u64 aux);

/* just like ulist_add_merge() but take a pointer for the aux data */
static inline int ulist_add_merge_ptr(struct ulist *ulist, u64 val, void *aux,
				      void **old_aux, gfp_t gfp_mask)
{
#if BITS_PER_LONG == 32
	u64 old64 = (uintptr_t)*old_aux;
	int ret = ulist_add_merge(ulist, val, (uintptr_t)aux, &old64, gfp_mask);
	*old_aux = (void *)((uintptr_t)old64);
	return ret;
#else
	return ulist_add_merge(ulist, val, (u64)aux, (u64 *)old_aux, gfp_mask);
#endif
}

struct ulist_node *ulist_next(struct ulist *ulist,
			      struct ulist_iterator *uiter);

#define ULIST_ITER_INIT(uiter) ((uiter)->cur_list = NULL)

#endif
Commit	Line	Data
da5c8135 AJ	1	/*
	2	* Copyright (C) 2011 STRATO AG
	3	* written by Arne Jansen <sensille@gmx.net>
	4	* Distributed under the GNU GPL license version 2.
	5	*
	6	*/
	7
	8	#ifndef __ULIST__
	9	#define __ULIST__
	10
f7f82b81 WS	11	#include <linux/list.h>
	12	#include <linux/rbtree.h>
	13
da5c8135 AJ	14	/*
	15	* ulist is a generic data structure to hold a collection of unique u64
	16	* values. The only operations it supports is adding to the list and
	17	* enumerating it.
	18	* It is possible to store an auxiliary value along with the key.
	19	*
da5c8135	20	*/
cd1b413c	21	struct ulist_iterator {
4c7a6f74	22	#ifdef CONFIG_BTRFS_DEBUG
cd1b413c	23	int i;
4c7a6f74 WS	24	#endif
4c7a6f74 WS	25	struct list_head cur_list; / hint to start search */
cd1b413c JS	26	};
cd1b413c JS	27
da5c8135 AJ	28	/*
	29	* element of the list
	30	*/
	31	struct ulist_node {
	32	u64 val; /* value to store */
34d73f54	33	u64 aux; /* auxiliary value saved along with the val */
4c7a6f74 WS	34
	35	#ifdef CONFIG_BTRFS_DEBUG
	36	int seqnum; /* sequence number this node is added */
	37	#endif
	38
	39	struct list_head list; /* used to link node */
f7f82b81	40	struct rb_node rb_node; /* used to speed up search */
da5c8135 AJ	41	};
	42
	43	struct ulist {
	44	/*
	45	* number of elements stored in list
	46	*/
	47	unsigned long nnodes;
	48
4c7a6f74	49	struct list_head nodes;
f7f82b81	50	struct rb_root root;
da5c8135 AJ	51	};
	52
	53	void ulist_init(struct ulist *ulist);
da5c8135	54	void ulist_reinit(struct ulist *ulist);
2eec6c81	55	struct ulist *ulist_alloc(gfp_t gfp_mask);
da5c8135	56	void ulist_free(struct ulist *ulist);
34d73f54 AB	57	int ulist_add(struct ulist *ulist, u64 val, u64 aux, gfp_t gfp_mask);
	58	int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux,
	59	u64 *old_aux, gfp_t gfp_mask);
d4b80404	60	int ulist_del(struct ulist *ulist, u64 val, u64 aux);
4eb1f66d TI	61
	62	/* just like ulist_add_merge() but take a pointer for the aux data */
	63	static inline int ulist_add_merge_ptr(struct ulist ulist, u64 val, void aux,
	64	void **old_aux, gfp_t gfp_mask)
	65	{
	66	#if BITS_PER_LONG == 32
	67	u64 old64 = (uintptr_t)*old_aux;
	68	int ret = ulist_add_merge(ulist, val, (uintptr_t)aux, &old64, gfp_mask);
	69	old_aux = (void )((uintptr_t)old64);
	70	return ret;
	71	#else
	72	return ulist_add_merge(ulist, val, (u64)aux, (u64 *)old_aux, gfp_mask);
	73	#endif
	74	}
	75
cd1b413c JS	76	struct ulist_node ulist_next(struct ulist ulist,
	77	struct ulist_iterator *uiter);
	78
4c7a6f74	79	#define ULIST_ITER_INIT(uiter) ((uiter)->cur_list = NULL)
da5c8135 AJ	80
da5c8135 AJ	81	#endif