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v0.5.1
https://github.com/torvalds/linux
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Tip revision: 5d0c230f1de8c7515b6567d9afba1f196fb4e2f4 authored by Linus Torvalds on 30 July 2023, 20:23:47 UTC
Linux 6.5-rc4
Tip revision: 5d0c230
dma-mapping.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_DMA_MAPPING_H
#define _LINUX_DMA_MAPPING_H

#ifdef CONFIG_HAS_DMA
# error Virtio userspace code does not support CONFIG_HAS_DMA
#endif

enum dma_data_direction {
	DMA_BIDIRECTIONAL = 0,
	DMA_TO_DEVICE = 1,
	DMA_FROM_DEVICE = 2,
	DMA_NONE = 3,
};

#define dma_alloc_coherent(d, s, hp, f) ({ \
	void *__dma_alloc_coherent_p = kmalloc((s), (f)); \
	*(hp) = (unsigned long)__dma_alloc_coherent_p; \
	__dma_alloc_coherent_p; \
})

#define dma_free_coherent(d, s, p, h) kfree(p)

#define dma_map_page(d, p, o, s, dir) (page_to_phys(p) + (o))

#define dma_map_single(d, p, s, dir) (virt_to_phys(p))
#define dma_mapping_error(...) (0)

#define dma_unmap_single(d, a, s, r) do { (void)(d); (void)(a); (void)(s); (void)(r); } while (0)
#define dma_unmap_page(d, a, s, r) do { (void)(d); (void)(a); (void)(s); (void)(r); } while (0)

#define dma_max_mapping_size(...) SIZE_MAX

#endif
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