linux/drivers/base/dma-mapping.c
Jacopo Mondi 60695be2bb dma-mapping: postpone cpu addr translation on mmap
Postpone calling virt_to_page() translation on memory locations not
guaranteed to be backed by a struct page.  Try first to map memory from
the device coherent memory pool, then perform translation if that fails.

On some architectures, specifically SH when configured with the SPARSEMEM
memory model, assuming a struct page is always assigned to a memory
address lead to unexpected hangs during the virtual to page address
translation. This patch fixes that specific issue but applies in the
general case too.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-04-23 14:44:24 +02:00

369 lines
8.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* 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>
*/
#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);
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;
#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
unsigned long user_count = vma_pages(vma);
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
unsigned long off = vma->vm_pgoff;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
return ret;
if (off < count && user_count <= (count - off))
ret = remap_pfn_range(vma, vma->vm_start,
page_to_pfn(virt_to_page(cpu_addr)) + 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);
}