linux-stable/include/linux/dma-iommu.h
Robin Murphy 3b6b7e19e3 iommu/dma: Finish optimising higher-order allocations
Now that we know exactly which page sizes our caller wants to use in the
given domain, we can restrict higher-order allocation attempts to just
those sizes, if any, and avoid wasting any time or effort on other sizes
which offer no benefit. In the same vein, this also lets us accommodate
a minimum order greater than 0 for special cases.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-05-09 15:33:29 +02:00

85 lines
2.7 KiB
C

/*
* Copyright (C) 2014-2015 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __DMA_IOMMU_H
#define __DMA_IOMMU_H
#ifdef __KERNEL__
#include <asm/errno.h>
#ifdef CONFIG_IOMMU_DMA
#include <linux/iommu.h>
int iommu_dma_init(void);
/* Domain management interface for IOMMU drivers */
int iommu_get_dma_cookie(struct iommu_domain *domain);
void iommu_put_dma_cookie(struct iommu_domain *domain);
/* Setup call for arch DMA mapping code */
int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size);
/* General helpers for DMA-API <-> IOMMU-API interaction */
int dma_direction_to_prot(enum dma_data_direction dir, bool coherent);
/*
* These implement the bulk of the relevant DMA mapping callbacks, but require
* the arch code to take care of attributes and cache maintenance
*/
struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
struct dma_attrs *attrs, int prot, dma_addr_t *handle,
void (*flush_page)(struct device *, const void *, phys_addr_t));
void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
dma_addr_t *handle);
int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma);
dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, int prot);
int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg,
int nents, int prot);
/*
* Arch code with no special attribute handling may use these
* directly as DMA mapping callbacks for simplicity
*/
void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
enum dma_data_direction dir, struct dma_attrs *attrs);
void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir, struct dma_attrs *attrs);
int iommu_dma_supported(struct device *dev, u64 mask);
int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
#else
struct iommu_domain;
static inline int iommu_dma_init(void)
{
return 0;
}
static inline int iommu_get_dma_cookie(struct iommu_domain *domain)
{
return -ENODEV;
}
static inline void iommu_put_dma_cookie(struct iommu_domain *domain)
{
}
#endif /* CONFIG_IOMMU_DMA */
#endif /* __KERNEL__ */
#endif /* __DMA_IOMMU_H */