drivers/comedi/comedi_buf.c

23 	struct comedi_buf_map *bm =
28 	if (bm->page_list) {
29 		if (bm->dma_dir != DMA_NONE) {
34 			buf = &bm->page_list[0];
35 			dma_free_coherent(bm->dma_hw_dev,
36 					  PAGE_SIZE * bm->n_pages,
39 			for (i = 0; i < bm->n_pages; i++) {
40 				buf = &bm->page_list[i];
45 		vfree(bm->page_list);
47 	if (bm->dma_dir != DMA_NONE)
48 		put_device(bm->dma_hw_dev);
49 	kfree(bm);
56 	struct comedi_buf_map *bm;
67 	bm = async->buf_map;
70 	comedi_buf_map_put(bm);
77 	struct comedi_buf_map *bm;
81 	bm = kzalloc(sizeof(*bm), GFP_KERNEL);
82 	if (!bm)
85 	kref_init(&bm->refcount);
86 	bm->dma_dir = dma_dir;
87 	if (bm->dma_dir != DMA_NONE) {
89 		bm->dma_hw_dev = get_device(dev->hw_dev);
92 	bm->page_list = vzalloc(sizeof(*buf) * n_pages);
93 	if (!bm->page_list)
96 	if (bm->dma_dir != DMA_NONE) {
104 		virt_addr = dma_alloc_coherent(bm->dma_hw_dev,
111 			buf = &bm->page_list[i];
116 		bm->n_pages = i;
119 			buf = &bm->page_list[i];
127 		bm->n_pages = i;
132 	return bm;
135 	comedi_buf_map_put(bm);
145 	struct comedi_buf_map *bm;
156 	bm = comedi_buf_map_alloc(dev, s->async_dma_dir, n_pages);
157 	if (!bm)
161 	async->buf_map = bm;
164 	if (bm->dma_dir != DMA_NONE) {
169 		buf = &bm->page_list[0];
177 			buf = &bm->page_list[i];
189 void comedi_buf_map_get(struct comedi_buf_map *bm)
191 	if (bm)
192 		kref_get(&bm->refcount);
195 int comedi_buf_map_put(struct comedi_buf_map *bm)
197 	if (bm)
198 		return kref_put(&bm->refcount, comedi_buf_map_kref_release);
203 int comedi_buf_map_access(struct comedi_buf_map *bm, unsigned long offset,
210 	while (done < len && pg < bm->n_pages) {
212 		void *b = bm->page_list[pg].virt_addr + pgoff;
231 	struct comedi_buf_map *bm = NULL;
238 	bm = async->buf_map;
240 	if (bm && bm->n_pages)
241 		comedi_buf_map_get(bm);
243 		bm = NULL;
246 	return bm;
251 	struct comedi_buf_map *bm = s->async->buf_map;
253 	return bm && (kref_read(&bm->refcount) > 1);