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 --- include/linux/page-flags.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/page-flags.h') diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index b848517da64c..f91cb8898ff0 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -152,6 +152,8 @@ enum pageflags { PG_savepinned = PG_dirty, /* Has a grant mapping of another (foreign) domain's page. */ PG_foreign = PG_owner_priv_1, + /* Remapped by swiotlb-xen. */ + PG_xen_remapped = PG_owner_priv_1, /* SLOB */ PG_slob_free = PG_private, @@ -329,6 +331,8 @@ PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND) TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND) PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND); PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND); +PAGEFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND) + TESTCLEARFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND) PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) -- cgit