/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_DMA_MAPPING_H
#define _LINUX_DMA_MAPPING_H

#include <linux/sizes.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/dma-debug.h>
#include <linux/dma-direction.h>
#include <linux/scatterlist.h>
#include <linux/bug.h>
#include <linux/mem_encrypt.h>

/**
 * List of possible attributes associated with a DMA mapping. The semantics
 * of each attribute should be defined in Documentation/DMA-attributes.txt.
 *
 * DMA_ATTR_WRITE_BARRIER: DMA to a memory region with this attribute
 * forces all pending DMA writes to complete.
 */
#define DMA_ATTR_WRITE_BARRIER          (1UL << 0)
/*
 * DMA_ATTR_WEAK_ORDERING: Specifies that reads and writes to the mapping
 * may be weakly ordered, that is that reads and writes may pass each other.
 */
#define DMA_ATTR_WEAK_ORDERING          (1UL << 1)
/*
 * DMA_ATTR_WRITE_COMBINE: Specifies that writes to the mapping may be
 * buffered to improve performance.
 */
#define DMA_ATTR_WRITE_COMBINE          (1UL << 2)
/*
 * DMA_ATTR_NON_CONSISTENT: Lets the platform to choose to return either
 * consistent or non-consistent memory as it sees fit.
 */
#define DMA_ATTR_NON_CONSISTENT         (1UL << 3)
/*
 * DMA_ATTR_NO_KERNEL_MAPPING: Lets the platform to avoid creating a kernel
 * virtual mapping for the allocated buffer.
 */
#define DMA_ATTR_NO_KERNEL_MAPPING      (1UL << 4)
/*
 * DMA_ATTR_SKIP_CPU_SYNC: Allows platform code to skip synchronization of
 * the CPU cache for the given buffer assuming that it has been already
 * transferred to 'device' domain.
 */
#define DMA_ATTR_SKIP_CPU_SYNC          (1UL << 5)
/*
 * DMA_ATTR_FORCE_CONTIGUOUS: Forces contiguous allocation of the buffer
 * in physical memory.
 */
#define DMA_ATTR_FORCE_CONTIGUOUS       (1UL << 6)
/*
 * DMA_ATTR_ALLOC_SINGLE_PAGES: This is a hint to the DMA-mapping subsystem
 * that it's probably not worth the time to try to allocate memory to in a way
 * that gives better TLB efficiency.
 */
#define DMA_ATTR_ALLOC_SINGLE_PAGES     (1UL << 7)
/*
 * DMA_ATTR_NO_WARN: This tells the DMA-mapping subsystem to suppress
 * allocation failure reports (similarly to __GFP_NOWARN).
 */
#define DMA_ATTR_NO_WARN        (1UL << 8)

/*
 * DMA_ATTR_PRIVILEGED: used to indicate that the buffer is fully
 * accessible at an elevated privilege level (and ideally inaccessible or
 * at least read-only at lesser-privileged levels).
 */
#define DMA_ATTR_PRIVILEGED             (1UL << 9)

/*
 * A dma_addr_t can hold any valid DMA or bus address for the platform.
 * It can be given to a device to use as a DMA source or target.  A CPU cannot
 * reference a dma_addr_t directly because there may be translation between
 * its physical address space and the bus address space.
 */
struct dma_map_ops {
        void* (*alloc)(struct device *dev, size_t size,
                                dma_addr_t *dma_handle, gfp_t gfp,
                                unsigned long attrs);
        void (*free)(struct device *dev, size_t size,
                              void *vaddr, dma_addr_t dma_handle,
                              unsigned long attrs);
        int (*mmap)(struct device *, struct vm_area_struct *,
                          void *, dma_addr_t, size_t,
                          unsigned long attrs);

        int (*get_sgtable)(struct device *dev, struct sg_table *sgt, void *,
                           dma_addr_t, size_t, unsigned long attrs);

        dma_addr_t (*map_page)(struct device *dev, struct page *page,
                               unsigned long offset, size_t size,
                               enum dma_data_direction dir,
                               unsigned long attrs);
        void (*unmap_page)(struct device *dev, dma_addr_t dma_handle,
                           size_t size, enum dma_data_direction dir,
                           unsigned long attrs);
        /*
         * map_sg returns 0 on error and a value > 0 on success.
         * It should never return a value < 0.
         */
        int (*map_sg)(struct device *dev, struct scatterlist *sg,
                      int nents, enum dma_data_direction dir,
                      unsigned long attrs);
        void (*unmap_sg)(struct device *dev,
                         struct scatterlist *sg, int nents,
                         enum dma_data_direction dir,
                         unsigned long attrs);
        dma_addr_t (*map_resource)(struct device *dev, phys_addr_t phys_addr,
                               size_t size, enum dma_data_direction dir,
                               unsigned long attrs);
        void (*unmap_resource)(struct device *dev, dma_addr_t dma_handle,
                           size_t size, enum dma_data_direction dir,
                           unsigned long attrs);
        void (*sync_single_for_cpu)(struct device *dev,
                                    dma_addr_t dma_handle, size_t size,
                                    enum dma_data_direction dir);
        void (*sync_single_for_device)(struct device *dev,
                                       dma_addr_t dma_handle, size_t size,
                                       enum dma_data_direction dir);
        void (*sync_sg_for_cpu)(struct device *dev,
                                struct scatterlist *sg, int nents,
                                enum dma_data_direction dir);
        void (*sync_sg_for_device)(struct device *dev,
                                   struct scatterlist *sg, int nents,
                                   enum dma_data_direction dir);
        void (*cache_sync)(struct device *dev, void *vaddr, size_t size,
                        enum dma_data_direction direction);
        int (*mapping_error)(struct device *dev, dma_addr_t dma_addr);
        int (*dma_supported)(struct device *dev, u64 mask);
#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
        u64 (*get_required_mask)(struct device *dev);
#endif
        int is_phys;
};

extern const struct dma_map_ops dma_noop_ops;
extern const struct dma_map_ops dma_virt_ops;

#define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))

#define DMA_MASK_NONE   0x0ULL

static inline int valid_dma_direction(int dma_direction)
{
        return ((dma_direction == DMA_BIDIRECTIONAL) ||
                (dma_direction == DMA_TO_DEVICE) ||
                (dma_direction == DMA_FROM_DEVICE));
}

static inline int is_device_dma_capable(struct device *dev)
{
        return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
}

#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
/*
 * These three functions are only for dma allocator.
 * Don't use them in device drivers.
 */
int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
                                       dma_addr_t *dma_handle, void **ret);
int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr);

int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
                            void *cpu_addr, size_t size, int *ret);

void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle);
int dma_release_from_global_coherent(int order, void *vaddr);
int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr,
                                  size_t size, int *ret);

#else
#define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0)
#define dma_release_from_dev_coherent(dev, order, vaddr) (0)
#define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0)

static inline void *dma_alloc_from_global_coherent(ssize_t size,
                                                   dma_addr_t *dma_handle)
{
        return NULL;
}

static inline int dma_release_from_global_coherent(int order, void *vaddr)
{
        return 0;
}

static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma,
                                                void *cpu_addr, size_t size,
                                                int *ret)
{
        return 0;
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */

#ifdef CONFIG_HAS_DMA
#include <asm/dma-mapping.h>
static inline const struct dma_map_ops *get_dma_ops(struct device *dev)
{
        if (dev && dev->dma_ops)
                return dev->dma_ops;
        return get_arch_dma_ops(dev ? dev->bus : NULL);
}

static inline void set_dma_ops(struct device *dev,
                               const struct dma_map_ops *dma_ops)
{
        dev->dma_ops = dma_ops;
}
#else
/*
 * Define the dma api to allow compilation but not linking of
 * dma dependent code.  Code that depends on the dma-mapping
 * API needs to set 'depends on HAS_DMA' in its Kconfig
 */
extern const struct dma_map_ops bad_dma_ops;
static inline const struct dma_map_ops *get_dma_ops(struct device *dev)
{
        return &bad_dma_ops;
}
#endif

static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
                                              size_t size,
                                              enum dma_data_direction dir,
                                              unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        dma_addr_t addr;

        BUG_ON(!valid_dma_direction(dir));
        addr = ops->map_page(dev, virt_to_page(ptr),
                             offset_in_page(ptr), size,
                             dir, attrs);
        debug_dma_map_page(dev, virt_to_page(ptr),
                           offset_in_page(ptr), size,
                           dir, addr, true);
        return addr;
}

static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
                                          size_t size,
                                          enum dma_data_direction dir,
                                          unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->unmap_page)
                ops->unmap_page(dev, addr, size, dir, attrs);
        debug_dma_unmap_page(dev, addr, size, dir, true);
}

/*
 * dma_maps_sg_attrs returns 0 on error and > 0 on success.
 * It should never return a value < 0.
 */
static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
                                   int nents, enum dma_data_direction dir,
                                   unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        int ents;

        BUG_ON(!valid_dma_direction(dir));
        ents = ops->map_sg(dev, sg, nents, dir, attrs);
        BUG_ON(ents < 0);
        debug_dma_map_sg(dev, sg, nents, ents, dir);

        return ents;
}

static inline void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
                                      int nents, enum dma_data_direction dir,
                                      unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        debug_dma_unmap_sg(dev, sg, nents, dir);
        if (ops->unmap_sg)
                ops->unmap_sg(dev, sg, nents, dir, attrs);
}

static inline dma_addr_t dma_map_page_attrs(struct device *dev,
                                            struct page *page,
                                            size_t offset, size_t size,
                                            enum dma_data_direction dir,
                                            unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        dma_addr_t addr;

        BUG_ON(!valid_dma_direction(dir));
        addr = ops->map_page(dev, page, offset, size, dir, attrs);
        debug_dma_map_page(dev, page, offset, size, dir, addr, false);

        return addr;
}

static inline void dma_unmap_page_attrs(struct device *dev,
                                        dma_addr_t addr, size_t size,
                                        enum dma_data_direction dir,
                                        unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->unmap_page)
                ops->unmap_page(dev, addr, size, dir, attrs);
        debug_dma_unmap_page(dev, addr, size, dir, false);
}

static inline dma_addr_t dma_map_resource(struct device *dev,
                                          phys_addr_t phys_addr,
                                          size_t size,
                                          enum dma_data_direction dir,
                                          unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        dma_addr_t addr;

        BUG_ON(!valid_dma_direction(dir));

        /* Don't allow RAM to be mapped */
        BUG_ON(pfn_valid(PHYS_PFN(phys_addr)));

        addr = phys_addr;
        if (ops->map_resource)
                addr = ops->map_resource(dev, phys_addr, size, dir, attrs);

        debug_dma_map_resource(dev, phys_addr, size, dir, addr);

        return addr;
}

static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
                                      size_t size, enum dma_data_direction dir,
                                      unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->unmap_resource)
                ops->unmap_resource(dev, addr, size, dir, attrs);
        debug_dma_unmap_resource(dev, addr, size, dir);
}

static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
                                           size_t size,
                                           enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->sync_single_for_cpu)
                ops->sync_single_for_cpu(dev, addr, size, dir);
        debug_dma_sync_single_for_cpu(dev, addr, size, dir);
}

static inline void dma_sync_single_for_device(struct device *dev,
                                              dma_addr_t addr, size_t size,
                                              enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->sync_single_for_device)
                ops->sync_single_for_device(dev, addr, size, dir);
        debug_dma_sync_single_for_device(dev, addr, size, dir);
}

static inline void dma_sync_single_range_for_cpu(struct device *dev,
                                                 dma_addr_t addr,
                                                 unsigned long offset,
                                                 size_t size,
                                                 enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->sync_single_for_cpu)
                ops->sync_single_for_cpu(dev, addr + offset, size, dir);
        debug_dma_sync_single_range_for_cpu(dev, addr, offset, size, dir);
}

static inline void dma_sync_single_range_for_device(struct device *dev,
                                                    dma_addr_t addr,
                                                    unsigned long offset,
                                                    size_t size,
                                                    enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->sync_single_for_device)
                ops->sync_single_for_device(dev, addr + offset, size, dir);
        debug_dma_sync_single_range_for_device(dev, addr, offset, size, dir);
}

static inline void
dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
                    int nelems, enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->sync_sg_for_cpu)
                ops->sync_sg_for_cpu(dev, sg, nelems, dir);
        debug_dma_sync_sg_for_cpu(dev, sg, nelems, dir);
}

static inline void
dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
                       int nelems, enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->sync_sg_for_device)
                ops->sync_sg_for_device(dev, sg, nelems, dir);
        debug_dma_sync_sg_for_device(dev, sg, nelems, dir);

}

#define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
#define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
#define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
#define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
#define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)

static inline void
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
                enum dma_data_direction dir)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!valid_dma_direction(dir));
        if (ops->cache_sync)
                ops->cache_sync(dev, vaddr, size, dir);
}

extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
                           void *cpu_addr, dma_addr_t dma_addr, size_t size);

void *dma_common_contiguous_remap(struct page *page, size_t size,
                        unsigned long vm_flags,
                        pgprot_t prot, const void *caller);

void *dma_common_pages_remap(struct page **pages, size_t size,
                        unsigned long vm_flags, pgprot_t prot,
                        const void *caller);
void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags);

/**
 * dma_mmap_attrs - map a coherent DMA allocation into user space
 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 * @vma: vm_area_struct describing requested user mapping
 * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs
 * @handle: device-view address returned from dma_alloc_attrs
 * @size: size of memory originally requested in dma_alloc_attrs
 * @attrs: attributes of mapping properties requested in dma_alloc_attrs
 *
 * Map a coherent DMA buffer previously allocated by dma_alloc_attrs
 * into user space.  The coherent DMA buffer must not be freed by the
 * driver until the user space mapping has been released.
 */
static inline int
dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, void *cpu_addr,
               dma_addr_t dma_addr, size_t size, unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        BUG_ON(!ops);
        if (ops->mmap)
                return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
        return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
}

#define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)

int
dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
                       void *cpu_addr, dma_addr_t dma_addr, size_t size);

static inline int
dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt, void *cpu_addr,
                      dma_addr_t dma_addr, size_t size,
                      unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        BUG_ON(!ops);
        if (ops->get_sgtable)
                return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size,
                                        attrs);
        return dma_common_get_sgtable(dev, sgt, cpu_addr, dma_addr, size);
}

#define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)

#ifndef arch_dma_alloc_attrs
#define arch_dma_alloc_attrs(dev, flag) (true)
#endif

static inline void *dma_alloc_attrs(struct device *dev, size_t size,
                                       dma_addr_t *dma_handle, gfp_t flag,
                                       unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);
        void *cpu_addr;

        BUG_ON(!ops);

        if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
                return cpu_addr;

        if (!arch_dma_alloc_attrs(&dev, &flag))
                return NULL;
        if (!ops->alloc)
                return NULL;

        cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
        debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
        return cpu_addr;
}

static inline void dma_free_attrs(struct device *dev, size_t size,
                                     void *cpu_addr, dma_addr_t dma_handle,
                                     unsigned long attrs)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        BUG_ON(!ops);
        WARN_ON(irqs_disabled());

        if (dma_release_from_dev_coherent(dev, get_order(size), cpu_addr))
                return;

        if (!ops->free || !cpu_addr)
                return;

        debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
        ops->free(dev, size, cpu_addr, dma_handle, attrs);
}

static inline void *dma_alloc_coherent(struct device *dev, size_t size,
                dma_addr_t *dma_handle, gfp_t flag)
{
        return dma_alloc_attrs(dev, size, dma_handle, flag, 0);
}

static inline void dma_free_coherent(struct device *dev, size_t size,
                void *cpu_addr, dma_addr_t dma_handle)
{
        return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
}

static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        debug_dma_mapping_error(dev, dma_addr);
        if (ops->mapping_error)
                return ops->mapping_error(dev, dma_addr);
        return 0;
}

static inline void dma_check_mask(struct device *dev, u64 mask)
{
        if (sme_active() && (mask < (((u64)sme_get_me_mask() << 1) - 1)))
                dev_warn(dev, "SME is active, device will require DMA bounce buffers\n");
}

static inline int dma_supported(struct device *dev, u64 mask)
{
        const struct dma_map_ops *ops = get_dma_ops(dev);

        if (!ops)
                return 0;
        if (!ops->dma_supported)
                return 1;
        return ops->dma_supported(dev, mask);
}

#ifndef HAVE_ARCH_DMA_SET_MASK
static inline int dma_set_mask(struct device *dev, u64 mask)
{
        if (!dev->dma_mask || !dma_supported(dev, mask))
                return -EIO;

        dma_check_mask(dev, mask);

        *dev->dma_mask = mask;
        return 0;
}
#endif

static inline u64 dma_get_mask(struct device *dev)
{
        if (dev && dev->dma_mask && *dev->dma_mask)
                return *dev->dma_mask;
        return DMA_BIT_MASK(32);
}

#ifdef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
int dma_set_coherent_mask(struct device *dev, u64 mask);
#else
static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
{
        if (!dma_supported(dev, mask))
                return -EIO;

        dma_check_mask(dev, mask);

        dev->coherent_dma_mask = mask;
        return 0;
}
#endif

/*
 * Set both the DMA mask and the coherent DMA mask to the same thing.
 * Note that we don't check the return value from dma_set_coherent_mask()
 * as the DMA API guarantees that the coherent DMA mask can be set to
 * the same or smaller than the streaming DMA mask.
 */
static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
{
        int rc = dma_set_mask(dev, mask);
        if (rc == 0)
                dma_set_coherent_mask(dev, mask);
        return rc;
}

/*
 * Similar to the above, except it deals with the case where the device
 * does not have dev->dma_mask appropriately setup.
 */
static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
{
        dev->dma_mask = &dev->coherent_dma_mask;
        return dma_set_mask_and_coherent(dev, mask);
}

extern u64 dma_get_required_mask(struct device *dev);

#ifndef arch_setup_dma_ops
static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base,
                                      u64 size, const struct iommu_ops *iommu,
                                      bool coherent) { }
#endif

#ifndef arch_teardown_dma_ops
static inline void arch_teardown_dma_ops(struct device *dev) { }
#endif

static inline unsigned int dma_get_max_seg_size(struct device *dev)
{
        if (dev->dma_parms && dev->dma_parms->max_segment_size)
                return dev->dma_parms->max_segment_size;
        return SZ_64K;
}

static inline unsigned int dma_set_max_seg_size(struct device *dev,
                                                unsigned int size)
{
        if (dev->dma_parms) {
                dev->dma_parms->max_segment_size = size;
                return 0;
        }
        return -EIO;
}

static inline unsigned long dma_get_seg_boundary(struct device *dev)
{
        if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
                return dev->dma_parms->segment_boundary_mask;
        return DMA_BIT_MASK(32);
}

static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
{
        if (dev->dma_parms) {
                dev->dma_parms->segment_boundary_mask = mask;
                return 0;
        }
        return -EIO;
}

#ifndef dma_max_pfn
static inline unsigned long dma_max_pfn(struct device *dev)
{
        return *dev->dma_mask >> PAGE_SHIFT;
}
#endif

static inline void *dma_zalloc_coherent(struct device *dev, size_t size,
                                        dma_addr_t *dma_handle, gfp_t flag)
{
        void *ret = dma_alloc_coherent(dev, size, dma_handle,
                                       flag | __GFP_ZERO);
        return ret;
}

static inline int dma_get_cache_alignment(void)
{
#ifdef ARCH_DMA_MINALIGN
        return ARCH_DMA_MINALIGN;
#endif
        return 1;
}

/* flags for the coherent memory api */
#define DMA_MEMORY_EXCLUSIVE            0x01

#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
                                dma_addr_t device_addr, size_t size, int flags);
void dma_release_declared_memory(struct device *dev);
void *dma_mark_declared_memory_occupied(struct device *dev,
                                        dma_addr_t device_addr, size_t size);
#else
static inline int
dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
                            dma_addr_t device_addr, size_t size, int flags)
{
        return -ENOSYS;
}

static inline void
dma_release_declared_memory(struct device *dev)
{
}

static inline void *
dma_mark_declared_memory_occupied(struct device *dev,
                                  dma_addr_t device_addr, size_t size)
{
        return ERR_PTR(-EBUSY);
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */

#ifdef CONFIG_HAS_DMA
int dma_configure(struct device *dev);
void dma_deconfigure(struct device *dev);
#else
static inline int dma_configure(struct device *dev)
{
        return 0;
}

static inline void dma_deconfigure(struct device *dev) {}
#endif

/*
 * Managed DMA API
 */
extern void *dmam_alloc_coherent(struct device *dev, size_t size,
                                 dma_addr_t *dma_handle, gfp_t gfp);
extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
                               dma_addr_t dma_handle);
extern void *dmam_alloc_attrs(struct device *dev, size_t size,
                              dma_addr_t *dma_handle, gfp_t gfp,
                              unsigned long attrs);
#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
extern int dmam_declare_coherent_memory(struct device *dev,
                                        phys_addr_t phys_addr,
                                        dma_addr_t device_addr, size_t size,
                                        int flags);
extern void dmam_release_declared_memory(struct device *dev);
#else /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
static inline int dmam_declare_coherent_memory(struct device *dev,
                                phys_addr_t phys_addr, dma_addr_t device_addr,
                                size_t size, gfp_t gfp)
{
        return 0;
}

static inline void dmam_release_declared_memory(struct device *dev)
{
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */

static inline void *dma_alloc_wc(struct device *dev, size_t size,
                                 dma_addr_t *dma_addr, gfp_t gfp)
{
        return dma_alloc_attrs(dev, size, dma_addr, gfp,
                               DMA_ATTR_WRITE_COMBINE);
}
#ifndef dma_alloc_writecombine
#define dma_alloc_writecombine dma_alloc_wc
#endif

static inline void dma_free_wc(struct device *dev, size_t size,
                               void *cpu_addr, dma_addr_t dma_addr)
{
        return dma_free_attrs(dev, size, cpu_addr, dma_addr,
                              DMA_ATTR_WRITE_COMBINE);
}
#ifndef dma_free_writecombine
#define dma_free_writecombine dma_free_wc
#endif

static inline int dma_mmap_wc(struct device *dev,
                              struct vm_area_struct *vma,
                              void *cpu_addr, dma_addr_t dma_addr,
                              size_t size)
{
        return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
                              DMA_ATTR_WRITE_COMBINE);
}
#ifndef dma_mmap_writecombine
#define dma_mmap_writecombine dma_mmap_wc
#endif

#if defined(CONFIG_NEED_DMA_MAP_STATE) || defined(CONFIG_DMA_API_DEBUG)
#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
#define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
#define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
#else
#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
#define dma_unmap_addr(PTR, ADDR_NAME)           (0)
#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
#define dma_unmap_len(PTR, LEN_NAME)             (0)
#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
#endif

#endif