diff options
Diffstat (limited to 'include/media/frame_vector.h')
| -rw-r--r-- | include/media/frame_vector.h | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/include/media/frame_vector.h b/include/media/frame_vector.h new file mode 100644 index 000000000..bfed1710d --- /dev/null +++ b/include/media/frame_vector.h @@ -0,0 +1,47 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifndef _MEDIA_FRAME_VECTOR_H +#define _MEDIA_FRAME_VECTOR_H + +/* Container for pinned pfns / pages in frame_vector.c */ +struct frame_vector { + unsigned int nr_allocated; /* Number of frames we have space for */ + unsigned int nr_frames; /* Number of frames stored in ptrs array */ + bool got_ref; /* Did we pin pages by getting page ref? */ + bool is_pfns; /* Does array contain pages or pfns? */ + void *ptrs[]; /* Array of pinned pfns / pages. Use + * pfns_vector_pages() or pfns_vector_pfns() + * for access */ +}; + +struct frame_vector *frame_vector_create(unsigned int nr_frames); +void frame_vector_destroy(struct frame_vector *vec); +int get_vaddr_frames(unsigned long start, unsigned int nr_pfns, + struct frame_vector *vec); +void put_vaddr_frames(struct frame_vector *vec); +int frame_vector_to_pages(struct frame_vector *vec); +void frame_vector_to_pfns(struct frame_vector *vec); + +static inline unsigned int frame_vector_count(struct frame_vector *vec) +{ + return vec->nr_frames; +} + +static inline struct page **frame_vector_pages(struct frame_vector *vec) +{ + if (vec->is_pfns) { + int err = frame_vector_to_pages(vec); + + if (err) + return ERR_PTR(err); + } + return (struct page **)(vec->ptrs); +} + +static inline unsigned long *frame_vector_pfns(struct frame_vector *vec) +{ + if (!vec->is_pfns) + frame_vector_to_pfns(vec); + return (unsigned long *)(vec->ptrs); +} + +#endif /* _MEDIA_FRAME_VECTOR_H */ |