From f14fb6c2db961c3665a61b342ab329b7bd20d1e7 Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Tue, 9 Mar 2021 11:27:37 +0100 Subject: dma: Introduce dma_aligned_pow2_mask() Currently get_naturally_aligned_size() is used by the intel iommu to compute the maximum invalidation range based on @size which is a power of 2 while being aligned with the @start address and less than the maximum range defined by @gaw. This helper is also useful for other iommu devices (virtio-iommu, SMMUv3) to make sure IOMMU UNMAP notifiers only are called with power of 2 range sizes. Let's move this latter into dma-helpers.c and rename it into dma_aligned_pow2_mask(). Also rewrite the helper so that it accomodates UINT64_MAX values for the size mask and max mask. It now returns a mask instead of a size. Change the caller. Signed-off-by: Eric Auger Reviewed-by: Peter Xu Message-id: 20210309102742.30442-3-eric.auger@redhat.com Signed-off-by: Peter Maydell --- hw/i386/intel_iommu.c | 30 +++++++----------------------- 1 file changed, 7 insertions(+), 23 deletions(-) (limited to 'hw/i386/intel_iommu.c') diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index 3206f379f8..6be8f32918 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -35,6 +35,7 @@ #include "hw/i386/x86-iommu.h" #include "hw/pci-host/q35.h" #include "sysemu/kvm.h" +#include "sysemu/dma.h" #include "sysemu/sysemu.h" #include "hw/i386/apic_internal.h" #include "kvm/kvm_i386.h" @@ -3455,24 +3456,6 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn) return vtd_dev_as; } -static uint64_t get_naturally_aligned_size(uint64_t start, - uint64_t size, int gaw) -{ - uint64_t max_mask = 1ULL << gaw; - uint64_t alignment = start ? start & -start : max_mask; - - alignment = MIN(alignment, max_mask); - size = MIN(size, max_mask); - - if (alignment <= size) { - /* Increase the alignment of start */ - return alignment; - } else { - /* Find the largest page mask from size */ - return 1ULL << (63 - clz64(size)); - } -} - /* Unmap the whole range in the notifier's scope. */ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) { @@ -3501,13 +3484,14 @@ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) while (remain >= VTD_PAGE_SIZE) { IOMMUTLBEvent event; - uint64_t mask = get_naturally_aligned_size(start, remain, s->aw_bits); + uint64_t mask = dma_aligned_pow2_mask(start, end, s->aw_bits); + uint64_t size = mask + 1; - assert(mask); + assert(size); event.type = IOMMU_NOTIFIER_UNMAP; event.entry.iova = start; - event.entry.addr_mask = mask - 1; + event.entry.addr_mask = mask; event.entry.target_as = &address_space_memory; event.entry.perm = IOMMU_NONE; /* This field is meaningless for unmap */ @@ -3515,8 +3499,8 @@ static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n) memory_region_notify_iommu_one(n, &event); - start += mask; - remain -= mask; + start += size; + remain -= size; } assert(!remain); -- cgit v1.2.3-55-g7522