xref: /openbmc/linux/include/media/frame_vector.h (revision b737eecd)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef _MEDIA_FRAME_VECTOR_H
3 #define _MEDIA_FRAME_VECTOR_H
4 
5 /* Container for pinned pfns / pages in frame_vector.c */
6 struct frame_vector {
7 	unsigned int nr_allocated;	/* Number of frames we have space for */
8 	unsigned int nr_frames;	/* Number of frames stored in ptrs array */
9 	bool got_ref;		/* Did we pin pages by getting page ref? */
10 	bool is_pfns;		/* Does array contain pages or pfns? */
11 	void *ptrs[];		/* Array of pinned pfns / pages. Use
12 				 * pfns_vector_pages() or pfns_vector_pfns()
13 				 * for access */
14 };
15 
16 struct frame_vector *frame_vector_create(unsigned int nr_frames);
17 void frame_vector_destroy(struct frame_vector *vec);
18 int get_vaddr_frames(unsigned long start, unsigned int nr_pfns,
19 		     struct frame_vector *vec);
20 void put_vaddr_frames(struct frame_vector *vec);
21 int frame_vector_to_pages(struct frame_vector *vec);
22 void frame_vector_to_pfns(struct frame_vector *vec);
23 
24 static inline unsigned int frame_vector_count(struct frame_vector *vec)
25 {
26 	return vec->nr_frames;
27 }
28 
29 static inline struct page **frame_vector_pages(struct frame_vector *vec)
30 {
31 	if (vec->is_pfns) {
32 		int err = frame_vector_to_pages(vec);
33 
34 		if (err)
35 			return ERR_PTR(err);
36 	}
37 	return (struct page **)(vec->ptrs);
38 }
39 
40 static inline unsigned long *frame_vector_pfns(struct frame_vector *vec)
41 {
42 	if (!vec->is_pfns)
43 		frame_vector_to_pfns(vec);
44 	return (unsigned long *)(vec->ptrs);
45 }
46 
47 #endif /* _MEDIA_FRAME_VECTOR_H */
48