linux/drivers/base/dma-mapping.c

375 lines
8.6 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/acpi.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
/*
* Managed DMA API
*/
struct dma_devres {
size_t size;
void *vaddr;
dma_addr_t dma_handle;
unsigned long attrs;
};
static void dmam_release(struct device *dev, void *res)
{
struct dma_devres *this = res;
dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
this->attrs);
}
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_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_release, dmam_match, &match_data));
}
EXPORT_SYMBOL(dmam_free_coherent);
/**
* dmam_alloc_attrs - Managed dma_alloc_attrs()
* @dev: Device to allocate non_coherent memory for
* @size: Size of allocation
* @dma_handle: Out argument for allocated DMA handle
* @gfp: Allocation flags
* @attrs: Flags in the DMA_ATTR_* namespace.
*
* Managed dma_alloc_attrs(). 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_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs)
{
struct dma_devres *dr;
void *vaddr;
dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
if (!dr)
return NULL;
vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
if (!vaddr) {
devres_free(dr);
return NULL;
}
dr->vaddr = vaddr;
dr->dma_handle = *dma_handle;
dr->size = size;
dr->attrs = attrs;
devres_add(dev, dr);
return vaddr;
}
EXPORT_SYMBOL(dmam_alloc_attrs);
#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
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) {
devres_add(dev, res);
rc = 0;
} else {
devres_free(res);
rc = -ENOMEM;
}
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;
#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
unsigned long user_count = vma_pages(vma);
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_ARCH_NO_COHERENT_DMA_MMAP */
return ret;
}
EXPORT_SYMBOL(dma_common_mmap);
#ifdef CONFIG_MMU
static struct vm_struct *__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;
if (map_vm_area(area, prot, pages)) {
vunmap(area->addr);
return NULL;
}
return area;
}
/*
* 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 = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
if (!area)
return NULL;
area->pages = pages;
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;
struct vm_struct *area;
pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
if (!pages)
return NULL;
for (i = 0; i < (size >> PAGE_SHIFT); i++)
pages[i] = nth_page(page, i);
area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
kfree(pages);
if (!area)
return NULL;
return area->addr;
}
/*
* 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, PAGE_ALIGN(size));
vunmap(cpu_addr);
}
#endif
/*
* Common configuration to enable DMA API use for a device
*/
#include <linux/pci.h>
int dma_configure(struct device *dev)
{
struct device *bridge = NULL, *dma_dev = dev;
enum dev_dma_attr attr;
int ret = 0;
if (dev_is_pci(dev)) {
bridge = pci_get_host_bridge_device(to_pci_dev(dev));
dma_dev = bridge;
if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
dma_dev->parent->of_node)
dma_dev = dma_dev->parent;
}
if (dma_dev->of_node) {
ret = of_dma_configure(dev, dma_dev->of_node);
} else if (has_acpi_companion(dma_dev)) {
attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode));
if (attr != DEV_DMA_NOT_SUPPORTED)
ret = acpi_dma_configure(dev, attr);
}
if (bridge)
pci_put_host_bridge_device(bridge);
return ret;
}
void dma_deconfigure(struct device *dev)
{
of_dma_deconfigure(dev);
acpi_dma_deconfigure(dev);
}