From: Kunkun Jiang jiangkunkun@huawei.com
virt inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8UZSP CVE: NA
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This realizes switch_dirty_log. In order to get finer dirty granule, it invokes arm_smmu_split_block when start dirty log, and invokes arm_smmu_merge_page() to recover block mapping when stop dirty log.
Co-developed-by: Keqian Zhu zhukeqian1@huawei.com Signed-off-by: Kunkun Jiang jiangkunkun@huawei.com Reviewed-by: Keqian Zhu zhukeqian1@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: jiaqingtong jiaqingtong@huawei.com --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 142 ++++++++++++++++++++ drivers/iommu/iommu.c | 5 +- include/linux/iommu.h | 2 + 3 files changed, 147 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 6b97c8d79c46..42e7e4d62084 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2833,6 +2833,147 @@ static int arm_smmu_enable_nesting(struct iommu_domain *domain) return ret; }
+static int arm_smmu_split_block(struct iommu_domain *domain, + unsigned long iova, size_t size) +{ + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); + struct arm_smmu_device *smmu = smmu_domain->smmu; + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; + size_t handled_size; + + if (!(smmu->features & (ARM_SMMU_FEAT_BBML1 | ARM_SMMU_FEAT_BBML2))) { + dev_err(smmu->dev, "don't support BBML1/2, can't split block\n"); + return -ENODEV; + } + if (!ops || !ops->split_block) { + pr_err("io-pgtable don't realize split block\n"); + return -ENODEV; + } + + handled_size = ops->split_block(ops, iova, size); + if (handled_size != size) { + pr_err("split block failed\n"); + return -EFAULT; + } + + return 0; +} + +static int __arm_smmu_merge_page(struct iommu_domain *domain, + unsigned long iova, phys_addr_t paddr, + size_t size, int prot) +{ + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; + size_t handled_size; + + if (!ops || !ops->merge_page) { + pr_err("io-pgtable don't realize merge page\n"); + return -ENODEV; + } + + while (size) { + size_t pgsize = iommu_pgsize(domain, iova | paddr, size); + + handled_size = ops->merge_page(ops, iova, paddr, pgsize, prot); + if (handled_size != pgsize) { + pr_err("merge page failed\n"); + return -EFAULT; + } + + pr_debug("merge handled: iova 0x%lx pa %pa size 0x%zx\n", + iova, &paddr, pgsize); + + iova += pgsize; + paddr += pgsize; + size -= pgsize; + } + + return 0; +} + +static int arm_smmu_merge_page(struct iommu_domain *domain, unsigned long iova, + size_t size, int prot) +{ + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); + struct arm_smmu_device *smmu = smmu_domain->smmu; + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; + phys_addr_t phys; + dma_addr_t p, i; + size_t cont_size; + int ret = 0; + + if (!(smmu->features & (ARM_SMMU_FEAT_BBML1 | ARM_SMMU_FEAT_BBML2))) { + dev_err(smmu->dev, "don't support BBML1/2, can't merge page\n"); + return -ENODEV; + } + + if (!ops || !ops->iova_to_phys) + return -ENODEV; + + while (size) { + phys = ops->iova_to_phys(ops, iova); + cont_size = PAGE_SIZE; + p = phys + cont_size; + i = iova + cont_size; + + while (cont_size < size && p == ops->iova_to_phys(ops, i)) { + p += PAGE_SIZE; + i += PAGE_SIZE; + cont_size += PAGE_SIZE; + } + + if (cont_size != PAGE_SIZE) { + ret = __arm_smmu_merge_page(domain, iova, phys, + cont_size, prot); + if (ret) + break; + } + + iova += cont_size; + size -= cont_size; + } + + return ret; +} + +static int arm_smmu_switch_dirty_log(struct iommu_domain *domain, bool enable, + unsigned long iova, size_t size, int prot) +{ + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); + struct arm_smmu_device *smmu = smmu_domain->smmu; + + if (!(smmu->features & ARM_SMMU_FEAT_HD)) + return -ENODEV; + if (smmu_domain->stage != ARM_SMMU_DOMAIN_S1) + return -EINVAL; + + if (enable) { + /* + * For SMMU, the hardware dirty management is always enabled if + * hardware supports HTTU HD. The action to start dirty log is + * spliting block mapping. + * + * We don't return error even if the split operation fail, as we + * can still track dirty at block granule, which is still a much + * better choice compared to full dirty policy. + */ + arm_smmu_split_block(domain, iova, size); + } else { + /* + * For SMMU, the hardware dirty management is always enabled if + * hardware supports HTTU HD. The action to stop dirty log is + * merging page mapping. + * + * We don't return error even if the merge operation fail, as it + * just effects performace of DMA transaction. + */ + arm_smmu_merge_page(domain, iova, size, prot); + } + + return 0; +} + static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args) { return iommu_fwspec_add_ids(dev, args->args, 1); @@ -2948,6 +3089,7 @@ static struct iommu_ops arm_smmu_ops = { .probe_device = arm_smmu_probe_device, .release_device = arm_smmu_release_device, .device_group = arm_smmu_device_group, + .switch_dirty_log = arm_smmu_switch_dirty_log, .of_xlate = arm_smmu_of_xlate, .get_resv_regions = arm_smmu_get_resv_regions, .remove_dev_pasid = arm_smmu_remove_dev_pasid, diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 3a67e636287a..7b2dc57f738d 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2364,8 +2364,8 @@ phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova) } EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
-static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova, - phys_addr_t paddr, size_t size, size_t *count) +size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, size_t *count) { unsigned int pgsize_idx, pgsize_idx_next; unsigned long pgsizes; @@ -2417,6 +2417,7 @@ static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova, *count = size >> pgsize_idx; return pgsize; } +EXPORT_SYMBOL_GPL(iommu_pgsize);
static int __iommu_map_pages(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t size, int prot, diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 0225cf7445de..c484ceda2c70 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -475,6 +475,8 @@ extern int iommu_sva_unbind_gpasid(struct iommu_domain *domain, struct device *dev, ioasid_t pasid); extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev); extern struct iommu_domain *iommu_get_dma_domain(struct device *dev); +extern size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, size_t *count); extern int iommu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t size, int prot, gfp_t gfp); extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,