From 5d52f482ebb7d0845e84cb235700061bc5682ada Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Tue, 20 Oct 2015 15:52:13 +0100 Subject: [PATCH] iommu/vt-d: Fix SVM IOTLB flush handling MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Change the 'pages' parameter to 'unsigned long' to avoid overflow. Fix the device-IOTLB flush parameter calculation — the size of the IOTLB flush is indicated by the position of the least significant zero bit in the address field. For example, a value of 0x12345f000 will flush from 0x123440000 to 0x12347ffff (256KiB). Finally, the cap_pgsel_inv() is not relevant to SVM; the spec says that *all* implementations must support page-selective invaliation for "first-level" translations. So don't check for it. Signed-off-by: David Woodhouse --- drivers/iommu/intel-svm.c | 35 +++++++++++++++-------------------- 1 file changed, 15 insertions(+), 20 deletions(-) diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index dd871d5888c7..a584df0767e6 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -147,13 +147,11 @@ int intel_svm_finish_prq(struct intel_iommu *iommu) } static void intel_flush_svm_range_dev (struct intel_svm *svm, struct intel_svm_dev *sdev, - unsigned long address, int pages, int ih, int gl) + unsigned long address, unsigned long pages, int ih, int gl) { struct qi_desc desc; - int mask = ilog2(__roundup_pow_of_two(pages)); - if (pages == -1 || !cap_pgsel_inv(svm->iommu->cap) || - mask > cap_max_amask_val(svm->iommu->cap)) { + if (pages == -1) { /* For global kernel pages we have to flush them in *all* PASIDs * because that's the only option the hardware gives us. Despite * the fact that they are actually only accessible through one. */ @@ -165,31 +163,28 @@ static void intel_flush_svm_range_dev (struct intel_svm *svm, struct intel_svm_d QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) | QI_EIOTLB_TYPE; desc.high = 0; } else { + int mask = ilog2(__roundup_pow_of_two(pages)); + desc.low = QI_EIOTLB_PASID(svm->pasid) | QI_EIOTLB_DID(sdev->did) | QI_EIOTLB_GRAN(QI_GRAN_PSI_PASID) | QI_EIOTLB_TYPE; desc.high = QI_EIOTLB_ADDR(address) | QI_EIOTLB_GL(gl) | QI_EIOTLB_IH(ih) | QI_EIOTLB_AM(mask); } - qi_submit_sync(&desc, svm->iommu); if (sdev->dev_iotlb) { desc.low = QI_DEV_EIOTLB_PASID(svm->pasid) | QI_DEV_EIOTLB_SID(sdev->sid) | QI_DEV_EIOTLB_QDEP(sdev->qdep) | QI_DEIOTLB_TYPE; - if (mask) { - unsigned long adr, delta; - - /* Least significant zero bits in the address indicate the - * range of the request. So mask them out according to the - * size. */ - adr = address & ((1<<(VTD_PAGE_SHIFT + mask)) - 1); - - /* Now ensure that we round down further if the original - * request was not aligned w.r.t. its size */ - delta = address - adr; - if (delta + (pages << VTD_PAGE_SHIFT) >= (1 << (VTD_PAGE_SHIFT + mask))) - adr &= ~(1 << (VTD_PAGE_SHIFT + mask)); - desc.high = QI_DEV_EIOTLB_ADDR(adr) | QI_DEV_EIOTLB_SIZE; + if (pages == -1) { + desc.high = QI_DEV_EIOTLB_ADDR(-1ULL >> 1) | QI_DEV_EIOTLB_SIZE; + } else if (pages > 1) { + /* The least significant zero bit indicates the size. So, + * for example, an "address" value of 0x12345f000 will + * flush from 0x123440000 to 0x12347ffff (256KiB). */ + unsigned long last = address + ((unsigned long)(pages - 1) << VTD_PAGE_SHIFT); + unsigned long mask = __rounddown_pow_of_two(address ^ last);; + + desc.high = QI_DEV_EIOTLB_ADDR((address & ~mask) | (mask - 1)) | QI_DEV_EIOTLB_SIZE; } else { desc.high = QI_DEV_EIOTLB_ADDR(address); } @@ -198,7 +193,7 @@ static void intel_flush_svm_range_dev (struct intel_svm *svm, struct intel_svm_d } static void intel_flush_svm_range(struct intel_svm *svm, unsigned long address, - int pages, int ih, int gl) + unsigned long pages, int ih, int gl) { struct intel_svm_dev *sdev; -- 2.39.2