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author | 2018-09-11 08:55:28 +0200 | |
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committer | 2018-09-20 09:01:16 +0200 | |
commit | 58b0440663ec11372befb8ead0ee7099d8878590 (patch) | |
tree | c613ed22ad229e6612d8c71888d2bb8139163ea8 /arch/microblaze/kernel/dma.c | |
parent | dma-mapping: merge direct and noncoherent ops (diff) | |
download | linux-58b0440663ec11372befb8ead0ee7099d8878590.tar.gz linux-58b0440663ec11372befb8ead0ee7099d8878590.tar.bz2 linux-58b0440663ec11372befb8ead0ee7099d8878590.zip |
dma-mapping: consolidate the dma mmap implementations
The only functional differences (modulo a few missing fixes in the arch
code) is that architectures without coherent caches need a hook to
convert a virtual or dma address into a pfn, given that we don't have
the kernel linear mapping available for the otherwise easy virt_to_page
call. As a side effect we can support mmap of the per-device coherent
area even on architectures not providing the callback, and we make
previous dangerous default methods dma_common_mmap actually save for
non-coherent architectures by rejecting it without the right helper.
In addition to that we need a hook so that some architectures can
override the protection bits when mmaping a dma coherent allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts
Diffstat (limited to 'arch/microblaze/kernel/dma.c')
-rw-r--r-- | arch/microblaze/kernel/dma.c | 22 |
1 files changed, 0 insertions, 22 deletions
diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c index 71032cf64669..a89c2d4ed5ff 100644 --- a/arch/microblaze/kernel/dma.c +++ b/arch/microblaze/kernel/dma.c @@ -42,25 +42,3 @@ void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr, { __dma_sync(dev, paddr, size, dir); } - -int arch_dma_mmap(struct device *dev, struct vm_area_struct *vma, - void *cpu_addr, dma_addr_t handle, size_t size, - unsigned long attrs) -{ -#ifdef CONFIG_MMU - unsigned long user_count = vma_pages(vma); - unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; - unsigned long off = vma->vm_pgoff; - unsigned long pfn; - - if (off >= count || user_count > (count - off)) - return -ENXIO; - - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - pfn = consistent_virt_to_pfn(cpu_addr); - return remap_pfn_range(vma, vma->vm_start, pfn + off, - vma->vm_end - vma->vm_start, vma->vm_page_prot); -#else - return -ENXIO; -#endif -} |