Commit 8fd2ed1c authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'stable/for-linus-5.14' of... 

Merge branch 'stable/for-linus-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb

Pull swiotlb fix from Konrad Rzeszutek Wilk:
 "A fix for the regression for the DMA operations where the offset was
  ignored and corruptions would appear.

  Going forward there will be a cleanups to make the offset and
  alignment logic more clearer and better test-cases to help with this"

* 'stable/for-linus-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb: manipulate orig_addr when tlb_addr has offset
parents 0c18f29a 5f89468e

kernel/dma/swiotlb.c

+15 −8
Original line number Diff line number Diff line
@@ -334,6 +334,14 @@ void __init swiotlb_exit(void) 
	io_tlb_default_mem = NULL;

}



/*

 * Return the offset into a iotlb slot required to keep the device happy.

 */

static unsigned int swiotlb_align_offset(struct device *dev, u64 addr)

{

	return addr & dma_get_min_align_mask(dev) & (IO_TLB_SIZE - 1);

}



/*

 * Bounce: copy the swiotlb buffer from or back to the original dma location

 */
@@ -346,10 +354,17 @@ static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size 
	size_t alloc_size = mem->slots[index].alloc_size;

	unsigned long pfn = PFN_DOWN(orig_addr);

	unsigned char *vaddr = phys_to_virt(tlb_addr);

	unsigned int tlb_offset;



	if (orig_addr == INVALID_PHYS_ADDR)

		return;



	tlb_offset = (tlb_addr & (IO_TLB_SIZE - 1)) -

		     swiotlb_align_offset(dev, orig_addr);



	orig_addr += tlb_offset;

	alloc_size -= tlb_offset;



	if (size > alloc_size) {

		dev_WARN_ONCE(dev, 1,

			"Buffer overflow detected. Allocation size: %zu. Mapping size: %zu.\n",
@@ -390,14 +405,6 @@ static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size 


#define slot_addr(start, idx)	((start) + ((idx) << IO_TLB_SHIFT))



/*

 * Return the offset into a iotlb slot required to keep the device happy.

 */

static unsigned int swiotlb_align_offset(struct device *dev, u64 addr)

{

	return addr & dma_get_min_align_mask(dev) & (IO_TLB_SIZE - 1);

}



/*

 * Carefully handle integer overflow which can occur when boundary_mask == ~0UL.

 */