diff options
| author | Jason Wang <jasowang@redhat.com> | 2017-01-20 14:35:28 +0800 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2017-02-01 03:37:17 +0200 |
| commit | 04eb6247eb1d95728b1e3e0078ba79f5b6d2ac25 (patch) | |
| tree | 3f4b8cc82f5fc3ebbfe852b9e06e16a8f8c421b4 | |
| parent | ec42813028d9ede3f9f73b8c943b00ff235ba0c1 (diff) | |
intel_iommu: fix and simplify size calculation in process_device_iotlb_desc()
We don't use 1ULL which is wrong during size calculation. Fix it, and
while at it, switch to use cto64() and adds a comments to make it
simpler and easier to be understood.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | hw/i386/intel_iommu.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index ec62239aba..3270fb9162 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -1485,8 +1485,16 @@ static bool vtd_process_device_iotlb_desc(IntelIOMMUState *s, goto done; } + /* According to ATS spec table 2.4: + * S = 0, bits 15:12 = xxxx range size: 4K + * S = 1, bits 15:12 = xxx0 range size: 8K + * S = 1, bits 15:12 = xx01 range size: 16K + * S = 1, bits 15:12 = x011 range size: 32K + * S = 1, bits 15:12 = 0111 range size: 64K + * ... + */ if (size) { - sz = 1 << (ctz64(~(addr | (VTD_PAGE_MASK_4K - 1))) + 1); + sz = (VTD_PAGE_SIZE * 2) << cto64(addr >> VTD_PAGE_SHIFT); addr &= ~(sz - 1); } else { sz = VTD_PAGE_SIZE; |