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/* Fallback functions when the main IOMMU code is not compiled in. This
code is roughly equivalent to i386. */
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <asm/proto.h>
#include <asm/processor.h>
int iommu_merge = 0;
EXPORT_SYMBOL(iommu_merge);
dma_addr_t bad_dma_address;
EXPORT_SYMBOL(bad_dma_address);
int iommu_bio_merge = 0;
EXPORT_SYMBOL(iommu_bio_merge);
int iommu_sac_force = 0;
EXPORT_SYMBOL(iommu_sac_force);
/*
* Dummy IO MMU functions
*/
void *dma_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp)
{
void *ret;
u64 mask;
int order = get_order(size);
if (hwdev)
mask = hwdev->coherent_dma_mask & *hwdev->dma_mask;
else
mask = 0xffffffff;
for (;;) {
ret = (void *)__get_free_pages(gfp, order);
if (ret == NULL)
return NULL;
*dma_handle = virt_to_bus(ret);
if ((*dma_handle & ~mask) == 0)
break;
free_pages((unsigned long)ret, order);
if (gfp & GFP_DMA)
return NULL;
gfp |= GFP_DMA;
}
memset(ret, 0, size);
return ret;
}
EXPORT_SYMBOL(dma_alloc_coherent);
void dma_free_coherent(struct device *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
free_pages((unsigned long)vaddr, get_order(size));
}
EXPORT_SYMBOL(dma_free_coherent);
int dma_supported(struct device *hwdev, u64 mask)
{
/*
* we fall back to GFP_DMA when the mask isn't all 1s,
* so we can't guarantee allocations that must be
* within a tighter range than GFP_DMA..
* RED-PEN this won't work for pci_map_single. Caller has to
* use GFP_DMA in the first place.
*/
if (mask < 0x00ffffff)
return 0;
return 1;
}
EXPORT_SYMBOL(dma_supported);
int dma_get_cache_alignment(void)
{
return boot_cpu_data.x86_clflush_size;
}
EXPORT_SYMBOL(dma_get_cache_alignment);
static int __init check_ram(void)
{
if (end_pfn >= 0xffffffff>>PAGE_SHIFT) {
printk(
KERN_ERR "WARNING more than 4GB of memory but IOMMU not compiled in.\n"
KERN_ERR "WARNING 32bit PCI may malfunction.\n");
}
return 0;
}
__initcall(check_ram);
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