linux/drivers/base/dma-mapping.c
Laura Abbott 513510ddba common: dma-mapping: introduce common remapping functions
For architectures without coherent DMA, memory for DMA may need to be
remapped with coherent attributes.  Factor out the the remapping code from
arm and put it in a common location to reduce code duplication.

As part of this, the arm APIs are now migrated away from
ioremap_page_range to the common APIs which use map_vm_area for remapping.
 This should be an equivalent change and using map_vm_area is more correct
as ioremap_page_range is intended to bring in io addresses into the cpu
space and not regular kernel managed memory.

Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Riley <davidriley@chromium.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Ritesh Harjain <ritesh.harjani@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:52 -04:00

342 lines
8.2 KiB
C

/*
* drivers/base/dma-mapping.c - arch-independent dma-mapping routines
*
* Copyright (c) 2006 SUSE Linux Products GmbH
* Copyright (c) 2006 Tejun Heo <teheo@suse.de>
*
* This file is released under the GPLv2.
*/
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <asm-generic/dma-coherent.h>
/*
* Managed DMA API
*/
struct dma_devres {
size_t size;
void *vaddr;
dma_addr_t dma_handle;
};
static void dmam_coherent_release(struct device *dev, void *res)
{
struct dma_devres *this = res;
dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
}
static void dmam_noncoherent_release(struct device *dev, void *res)
{
struct dma_devres *this = res;
dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
}
static int dmam_match(struct device *dev, void *res, void *match_data)
{
struct dma_devres *this = res, *match = match_data;
if (this->vaddr == match->vaddr) {
WARN_ON(this->size != match->size ||
this->dma_handle != match->dma_handle);
return 1;
}
return 0;
}
/**
* dmam_alloc_coherent - Managed dma_alloc_coherent()
* @dev: Device to allocate coherent memory for
* @size: Size of allocation
* @dma_handle: Out argument for allocated DMA handle
* @gfp: Allocation flags
*
* Managed dma_alloc_coherent(). Memory allocated using this function
* will be automatically released on driver detach.
*
* RETURNS:
* Pointer to allocated memory on success, NULL on failure.
*/
void * dmam_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp)
{
struct dma_devres *dr;
void *vaddr;
dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
if (!dr)
return NULL;
vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
if (!vaddr) {
devres_free(dr);
return NULL;
}
dr->vaddr = vaddr;
dr->dma_handle = *dma_handle;
dr->size = size;
devres_add(dev, dr);
return vaddr;
}
EXPORT_SYMBOL(dmam_alloc_coherent);
/**
* dmam_free_coherent - Managed dma_free_coherent()
* @dev: Device to free coherent memory for
* @size: Size of allocation
* @vaddr: Virtual address of the memory to free
* @dma_handle: DMA handle of the memory to free
*
* Managed dma_free_coherent().
*/
void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle)
{
struct dma_devres match_data = { size, vaddr, dma_handle };
dma_free_coherent(dev, size, vaddr, dma_handle);
WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
&match_data));
}
EXPORT_SYMBOL(dmam_free_coherent);
/**
* dmam_alloc_non_coherent - Managed dma_alloc_non_coherent()
* @dev: Device to allocate non_coherent memory for
* @size: Size of allocation
* @dma_handle: Out argument for allocated DMA handle
* @gfp: Allocation flags
*
* Managed dma_alloc_non_coherent(). Memory allocated using this
* function will be automatically released on driver detach.
*
* RETURNS:
* Pointer to allocated memory on success, NULL on failure.
*/
void *dmam_alloc_noncoherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp)
{
struct dma_devres *dr;
void *vaddr;
dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
if (!dr)
return NULL;
vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
if (!vaddr) {
devres_free(dr);
return NULL;
}
dr->vaddr = vaddr;
dr->dma_handle = *dma_handle;
dr->size = size;
devres_add(dev, dr);
return vaddr;
}
EXPORT_SYMBOL(dmam_alloc_noncoherent);
/**
* dmam_free_coherent - Managed dma_free_noncoherent()
* @dev: Device to free noncoherent memory for
* @size: Size of allocation
* @vaddr: Virtual address of the memory to free
* @dma_handle: DMA handle of the memory to free
*
* Managed dma_free_noncoherent().
*/
void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle)
{
struct dma_devres match_data = { size, vaddr, dma_handle };
dma_free_noncoherent(dev, size, vaddr, dma_handle);
WARN_ON(!devres_destroy(dev, dmam_noncoherent_release, dmam_match,
&match_data));
}
EXPORT_SYMBOL(dmam_free_noncoherent);
#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
static void dmam_coherent_decl_release(struct device *dev, void *res)
{
dma_release_declared_memory(dev);
}
/**
* dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
* @dev: Device to declare coherent memory for
* @phys_addr: Physical address of coherent memory to be declared
* @device_addr: Device address of coherent memory to be declared
* @size: Size of coherent memory to be declared
* @flags: Flags
*
* Managed dma_declare_coherent_memory().
*
* RETURNS:
* 0 on success, -errno on failure.
*/
int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int flags)
{
void *res;
int rc;
res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
if (!res)
return -ENOMEM;
rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
flags);
if (rc == 0)
devres_add(dev, res);
else
devres_free(res);
return rc;
}
EXPORT_SYMBOL(dmam_declare_coherent_memory);
/**
* dmam_release_declared_memory - Managed dma_release_declared_memory().
* @dev: Device to release declared coherent memory for
*
* Managed dmam_release_declared_memory().
*/
void dmam_release_declared_memory(struct device *dev)
{
WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
}
EXPORT_SYMBOL(dmam_release_declared_memory);
#endif
/*
* Create scatter-list for the already allocated DMA buffer.
*/
int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
void *cpu_addr, dma_addr_t handle, size_t size)
{
struct page *page = virt_to_page(cpu_addr);
int ret;
ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
if (unlikely(ret))
return ret;
sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
return 0;
}
EXPORT_SYMBOL(dma_common_get_sgtable);
/*
* Create userspace mapping for the DMA-coherent memory.
*/
int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size)
{
int ret = -ENXIO;
#ifdef CONFIG_MMU
unsigned long user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
unsigned long off = vma->vm_pgoff;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
return ret;
if (off < count && user_count <= (count - off)) {
ret = remap_pfn_range(vma, vma->vm_start,
pfn + off,
user_count << PAGE_SHIFT,
vma->vm_page_prot);
}
#endif /* CONFIG_MMU */
return ret;
}
EXPORT_SYMBOL(dma_common_mmap);
#ifdef CONFIG_MMU
/*
* remaps an array of PAGE_SIZE pages into another vm_area
* Cannot be used in non-sleeping contexts
*/
void *dma_common_pages_remap(struct page **pages, size_t size,
unsigned long vm_flags, pgprot_t prot,
const void *caller)
{
struct vm_struct *area;
area = get_vm_area_caller(size, vm_flags, caller);
if (!area)
return NULL;
area->pages = pages;
if (map_vm_area(area, prot, pages)) {
vunmap(area->addr);
return NULL;
}
return area->addr;
}
/*
* remaps an allocated contiguous region into another vm_area.
* Cannot be used in non-sleeping contexts
*/
void *dma_common_contiguous_remap(struct page *page, size_t size,
unsigned long vm_flags,
pgprot_t prot, const void *caller)
{
int i;
struct page **pages;
void *ptr;
unsigned long pfn;
pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
if (!pages)
return NULL;
for (i = 0, pfn = page_to_pfn(page); i < (size >> PAGE_SHIFT); i++)
pages[i] = pfn_to_page(pfn + i);
ptr = dma_common_pages_remap(pages, size, vm_flags, prot, caller);
kfree(pages);
return ptr;
}
/*
* unmaps a range previously mapped by dma_common_*_remap
*/
void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
{
struct vm_struct *area = find_vm_area(cpu_addr);
if (!area || (area->flags & vm_flags) != vm_flags) {
WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
return;
}
unmap_kernel_range((unsigned long)cpu_addr, size);
vunmap(cpu_addr);
}
#endif