[linux.git] / fs / squashfs / page_actor.h

#ifndef PAGE_ACTOR_H
#define PAGE_ACTOR_H
/*
 * Copyright (c) 2013
 * Phillip Lougher <[email protected]>
 *
 * This work is licensed under the terms of the GNU GPL, version 2. See
 * the COPYING file in the top-level directory.
 */

#ifndef CONFIG_SQUASHFS_FILE_DIRECT
struct squashfs_page_actor {
	void	**page;
	int	pages;
	int	length;
	int	next_page;
};

static inline struct squashfs_page_actor *squashfs_page_actor_init(void **page,
	int pages, int length)
{
	struct squashfs_page_actor *actor = kmalloc(sizeof(*actor), GFP_KERNEL);

	if (actor == NULL)
		return NULL;

	actor->length = length ? : pages * PAGE_SIZE;
	actor->page = page;
	actor->pages = pages;
	actor->next_page = 0;
	return actor;
}

static inline void *squashfs_first_page(struct squashfs_page_actor *actor)
{
	actor->next_page = 1;
	return actor->page[0];
}

static inline void *squashfs_next_page(struct squashfs_page_actor *actor)
{
	return actor->next_page == actor->pages ? NULL :
		actor->page[actor->next_page++];
}

static inline void squashfs_finish_page(struct squashfs_page_actor *actor)
{
	/* empty */
}
#else
struct squashfs_page_actor {
	union {
		void		**buffer;
		struct page	**page;
	};
	void	*pageaddr;
	void    *(*squashfs_first_page)(struct squashfs_page_actor *);
	void    *(*squashfs_next_page)(struct squashfs_page_actor *);
	void    (*squashfs_finish_page)(struct squashfs_page_actor *);
	int	pages;
	int	length;
	int	next_page;
};

extern struct squashfs_page_actor *squashfs_page_actor_init(void **, int, int);
extern struct squashfs_page_actor *squashfs_page_actor_init_special(struct page
							 **, int, int);
static inline void *squashfs_first_page(struct squashfs_page_actor *actor)
{
	return actor->squashfs_first_page(actor);
}
static inline void *squashfs_next_page(struct squashfs_page_actor *actor)
{
	return actor->squashfs_next_page(actor);
}
static inline void squashfs_finish_page(struct squashfs_page_actor *actor)
{
	actor->squashfs_finish_page(actor);
}
#endif
#endif
Commit	Line	Data
846b730e PL	1	#ifndef PAGE_ACTOR_H
	2	#define PAGE_ACTOR_H
	3	/*
	4	* Copyright (c) 2013
	5	* Phillip Lougher <[email protected]>
	6	*
	7	* This work is licensed under the terms of the GNU GPL, version 2. See
	8	* the COPYING file in the top-level directory.
	9	*/
	10
0d455c12	11	#ifndef CONFIG_SQUASHFS_FILE_DIRECT
846b730e PL	12	struct squashfs_page_actor {
	13	void **page;
	14	int pages;
	15	int length;
	16	int next_page;
	17	};
	18
	19	static inline struct squashfs_page_actor squashfs_page_actor_init(void *page,
	20	int pages, int length)
	21	{
	22	struct squashfs_page_actor actor = kmalloc(sizeof(actor), GFP_KERNEL);
	23
	24	if (actor == NULL)
	25	return NULL;
	26
09cbfeaf	27	actor->length = length ? : pages * PAGE_SIZE;
846b730e PL	28	actor->page = page;
	29	actor->pages = pages;
	30	actor->next_page = 0;
	31	return actor;
	32	}
	33
	34	static inline void squashfs_first_page(struct squashfs_page_actor actor)
	35	{
	36	actor->next_page = 1;
	37	return actor->page[0];
	38	}
	39
	40	static inline void squashfs_next_page(struct squashfs_page_actor actor)
	41	{
	42	return actor->next_page == actor->pages ? NULL :
	43	actor->page[actor->next_page++];
	44	}
	45
	46	static inline void squashfs_finish_page(struct squashfs_page_actor *actor)
	47	{
	48	/* empty */
	49	}
0d455c12 PL	50	#else
	51	struct squashfs_page_actor {
	52	union {
	53	void **buffer;
	54	struct page **page;
	55	};
	56	void *pageaddr;
	57	void (squashfs_first_page)(struct squashfs_page_actor *);
	58	void (squashfs_next_page)(struct squashfs_page_actor *);
	59	void (squashfs_finish_page)(struct squashfs_page_actor );
	60	int pages;
	61	int length;
	62	int next_page;
	63	};
	64
	65	extern struct squashfs_page_actor squashfs_page_actor_init(void *, int, int);
	66	extern struct squashfs_page_actor *squashfs_page_actor_init_special(struct page
	67	**, int, int);
	68	static inline void squashfs_first_page(struct squashfs_page_actor actor)
	69	{
	70	return actor->squashfs_first_page(actor);
	71	}
	72	static inline void squashfs_next_page(struct squashfs_page_actor actor)
	73	{
	74	return actor->squashfs_next_page(actor);
	75	}
	76	static inline void squashfs_finish_page(struct squashfs_page_actor *actor)
	77	{
	78	actor->squashfs_finish_page(actor);
	79	}
	80	#endif
846b730e	81	#endif