Commit 28148a17 authored by Jann Horn's avatar Jann Horn Committed by Stafford Horne
Browse files

openrisc: Fix pagewalk usage in arch_dma_{clear, set}_uncached 



Since commit 8782fb61 ("mm: pagewalk: Fix race between unmap and page
walker"), walk_page_range() on kernel ranges won't work anymore,
walk_page_range_novma() must be used instead.

Note: I don't have an openrisc development setup, so this is completely
untested.

Fixes: 8782fb61 ("mm: pagewalk: Fix race between unmap and page walker")
Signed-off-by: default avatarJann Horn <jannh@google.com>
Signed-off-by: default avatarStafford Horne <shorne@gmail.com>
parent f76349cf

arch/openrisc/kernel/dma.c

+8 −8
Original line number Diff line number Diff line
@@ -74,10 +74,10 @@ void *arch_dma_set_uncached(void *cpu_addr, size_t size) 
	 * We need to iterate through the pages, clearing the dcache for

	 * them and setting the cache-inhibit bit.

	 */

	mmap_read_lock(&init_mm);

	error = walk_page_range(&init_mm, va, va + size, &set_nocache_walk_ops,

			NULL);

	mmap_read_unlock(&init_mm);

	mmap_write_lock(&init_mm);

	error = walk_page_range_novma(&init_mm, va, va + size,

			&set_nocache_walk_ops, NULL, NULL);

	mmap_write_unlock(&init_mm);



	if (error)

		return ERR_PTR(error);
@@ -88,11 +88,11 @@ void arch_dma_clear_uncached(void *cpu_addr, size_t size) 
{

	unsigned long va = (unsigned long)cpu_addr;



	mmap_read_lock(&init_mm);

	mmap_write_lock(&init_mm);

	/* walk_page_range shouldn't be able to fail here */

	WARN_ON(walk_page_range(&init_mm, va, va + size,

			&clear_nocache_walk_ops, NULL));

	mmap_read_unlock(&init_mm);

	WARN_ON(walk_page_range_novma(&init_mm, va, va + size,

			&clear_nocache_walk_ops, NULL, NULL));

	mmap_write_unlock(&init_mm);

}



void arch_sync_dma_for_device(phys_addr_t addr, size_t size,