From b877ac9815a8fe7e5f6d7fdde3dc34652408840a Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 14 Jun 2019 07:46:04 +0200 Subject: xen/swiotlb: remember having called xen_create_contiguous_region() Instead of always calling xen_destroy_contiguous_region() in case the memory is DMA-able for the used device, do so only in case it has been made DMA-able via xen_create_contiguous_region() before. This will avoid a lot of xen_destroy_contiguous_region() calls for 64-bit capable devices. As the memory in question is owned by swiotlb-xen the PG_owner_priv_1 flag of the first allocated page can be used for remembering. Signed-off-by: Juergen Gross Acked-by: Konrad Rzeszutek Wilk Signed-off-by: Juergen Gross --- drivers/xen/swiotlb-xen.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/xen') diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 37ddcfcfbb21..ceb681cf64bb 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -322,6 +322,7 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, xen_free_coherent_pages(hwdev, size, ret, (dma_addr_t)phys, attrs); return NULL; } + SetPageXenRemapped(virt_to_page(ret)); } memset(ret, 0, size); return ret; @@ -346,7 +347,8 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, size = 1UL << (order + XEN_PAGE_SHIFT); if (!WARN_ON((dev_addr + size - 1 > dma_mask) || - range_straddles_page_boundary(phys, size))) + range_straddles_page_boundary(phys, size)) && + TestClearPageXenRemapped(virt_to_page(vaddr))) xen_destroy_contiguous_region(phys, order); xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs); -- cgit v1.2.3