65 lines
1.9 KiB
C
65 lines
1.9 KiB
C
#ifndef PAGE_ACTOR_H
|
|
#define PAGE_ACTOR_H
|
|
/*
|
|
* Copyright (c) 2013
|
|
* Phillip Lougher <phillip@squashfs.org.uk>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2. See
|
|
* the COPYING file in the top-level squashfsory.
|
|
*/
|
|
|
|
struct squashfs_page_actor {
|
|
struct page **page;
|
|
void *pageaddr;
|
|
int pages;
|
|
int length;
|
|
int next_page;
|
|
void (*release_pages)(struct page **, int, int);
|
|
};
|
|
|
|
extern struct squashfs_page_actor *squashfs_page_actor_init(struct page **,
|
|
int, int, void (*)(struct page **, int, int));
|
|
extern void squashfs_page_actor_free(struct squashfs_page_actor *, int);
|
|
|
|
extern void squashfs_actor_to_buf(struct squashfs_page_actor *, void *, int);
|
|
extern void squashfs_buf_to_actor(void *, struct squashfs_page_actor *, int);
|
|
extern void squashfs_bh_to_actor(struct buffer_head **, int,
|
|
struct squashfs_page_actor *, int, int, int);
|
|
extern void squashfs_bh_to_buf(struct buffer_head **, int, void *, int, int,
|
|
int);
|
|
|
|
/*
|
|
* Calling code should avoid sleeping between calls to squashfs_first_page()
|
|
* and squashfs_finish_page().
|
|
*/
|
|
static inline void *squashfs_first_page(struct squashfs_page_actor *actor)
|
|
{
|
|
actor->next_page = 1;
|
|
return actor->pageaddr = actor->page[0] ? kmap_atomic(actor->page[0])
|
|
: NULL;
|
|
}
|
|
|
|
static inline void *squashfs_next_page(struct squashfs_page_actor *actor)
|
|
{
|
|
if (!IS_ERR_OR_NULL(actor->pageaddr))
|
|
kunmap_atomic(actor->pageaddr);
|
|
|
|
if (actor->next_page == actor->pages)
|
|
return actor->pageaddr = ERR_PTR(-ENODATA);
|
|
|
|
actor->pageaddr = actor->page[actor->next_page] ?
|
|
kmap_atomic(actor->page[actor->next_page]) : NULL;
|
|
++actor->next_page;
|
|
return actor->pageaddr;
|
|
}
|
|
|
|
static inline void squashfs_finish_page(struct squashfs_page_actor *actor)
|
|
{
|
|
if (!IS_ERR_OR_NULL(actor->pageaddr))
|
|
kunmap_atomic(actor->pageaddr);
|
|
}
|
|
|
|
extern struct page **alloc_page_array(int, int);
|
|
extern void free_page_array(struct page **, int);
|
|
|
|
#endif
|