Commit 876f29b7 authored by Jingxian He's avatar Jingxian He Committed by hejingxian
Browse files

swiotlb: add swiotlb io_tlb_list release slots methd 

virtcca inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I9CC0X



--------------------------------

Add swiotlb release slots methd for io_tlb_list.

Signed-off-by: default avatarJingxian He <hejingxian@huawei.com>
parent 13c10762

kernel/dma/swiotlb.c

+36 −0
Original line number Diff line number Diff line
@@ -798,6 +798,42 @@ struct page *swiotlb_alloc(struct device *dev, size_t size) 
static void swiotlb_release_slots(struct device *dev, phys_addr_t tlb_addr,

		size_t alloc_size)

{

	unsigned long flags;

	unsigned int offset = swiotlb_align_offset(dev, tlb_addr);

	int i, count, nslots = nr_slots(alloc_size + offset);

	int index = (tlb_addr - offset - io_tlb_start) >> IO_TLB_SHIFT;



	/*

	 * Return the buffer to the free list by setting the corresponding

	 * entries to indicate the number of contiguous entries available.

	 * While returning the entries to the free list, we merge the entries

	 * with slots below and above the pool being returned.

	 */

	spin_lock_irqsave(&io_tlb_lock, flags);

	if (index + nslots < ALIGN(index + 1, IO_TLB_SEGSIZE))

		count = io_tlb_list[index + nslots];

	else

		count = 0;



	/*

	 * Step 1: return the slots to the free list, merging the slots with

	 * superceeding slots

	 */

	for (i = index + nslots - 1; i >= index; i--) {

		io_tlb_list[i] = ++count;

		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;

	}



	/*

	 * Step 2: merge the returned slots with the preceding slots, if

	 * available (non zero)

	 */

	for (i = index - 1;

		 io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && io_tlb_list[i];

		 i--)

		io_tlb_list[i] = ++count;

	io_tlb_used -= nslots;

	spin_unlock_irqrestore(&io_tlb_lock, flags);

}



bool swiotlb_free(struct device *dev, struct page *page, size_t size)