Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Keqian Zhu <zhukeqian1@huawei.com>
To:     <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <iommu@lists.linux-foundation.org>,
        Robin Murphy <robin.murphy@arm.com>,
        "Will Deacon" <will@kernel.org>, Joerg Roedel <joro@8bytes.org>,
        Yi Sun <yi.y.sun@linux.intel.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Tian Kevin <kevin.tian@intel.com>,
        Lu Baolu <baolu.lu@linux.intel.com>
CC:     Alex Williamson <alex.williamson@redhat.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Kirti Wankhede <kwankhede@nvidia.com>,
        <wanghaibin.wang@huawei.com>, <jiangkunkun@huawei.com>,
        <yuzenghui@huawei.com>, <lushenming@huawei.com>
Subject: [PATCH v3 10/12] iommu/arm-smmu-v3: Realize sync_dirty_log iommu ops
Date:   Tue, 13 Apr 2021 16:54:55 +0800
Message-ID: <20210413085457.25400-11-zhukeqian1@huawei.com>
In-Reply-To: <20210413085457.25400-1-zhukeqian1@huawei.com>
References: <20210413085457.25400-1-zhukeqian1@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

From: Kunkun Jiang <jiangkunkun@huawei.com>

During dirty log tracking, user will try to retrieve dirty log from
iommu if it supports hardware dirty log. Scan leaf TTD and treat it
is dirty if it's writable. As we just enable HTTU for stage1, so
check whether AP[2] is not set.

Co-developed-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 30 +++++++
 drivers/iommu/io-pgtable-arm.c              | 90 +++++++++++++++++++++
 include/linux/io-pgtable.h                  |  4 +
 3 files changed, 124 insertions(+)

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 52c6f3e74d6f..9eb209a07acc 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2627,6 +2627,35 @@ static int arm_smmu_switch_dirty_log(struct iommu_domain *domain, bool enable,
 	return 0;
 }
 
+static int arm_smmu_sync_dirty_log(struct iommu_domain *domain,
+				   unsigned long iova, size_t size,
+				   unsigned long *bitmap,
+				   unsigned long base_iova,
+				   unsigned long bitmap_pgshift)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
+	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 (!ops || !ops->sync_dirty_log) {
+		pr_err("io-pgtable don't realize sync dirty log\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * Flush iotlb to ensure all inflight transactions are completed.
+	 * See doc IHI0070Da 3.13.4 "HTTU behavior summary".
+	 */
+	arm_smmu_flush_iotlb_all(domain);
+	return ops->sync_dirty_log(ops, iova, size, bitmap, base_iova,
+				   bitmap_pgshift);
+}
+
 static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
 {
 	return iommu_fwspec_add_ids(dev, args->args, 1);
@@ -2729,6 +2758,7 @@ static struct iommu_ops arm_smmu_ops = {
 	.split_block		= arm_smmu_split_block,
 	.merge_page		= arm_smmu_merge_page,
 	.switch_dirty_log	= arm_smmu_switch_dirty_log,
+	.sync_dirty_log		= arm_smmu_sync_dirty_log,
 	.of_xlate		= arm_smmu_of_xlate,
 	.get_resv_regions	= arm_smmu_get_resv_regions,
 	.put_resv_regions	= generic_iommu_put_resv_regions,
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 9028328b99b0..67a208a05ab2 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -877,6 +877,95 @@ static size_t arm_lpae_merge_page(struct io_pgtable_ops *ops, unsigned long iova
 	return __arm_lpae_merge_page(data, iova, paddr, size, lvl, ptep, prot);
 }
 
+static int __arm_lpae_sync_dirty_log(struct arm_lpae_io_pgtable *data,
+				     unsigned long iova, size_t size,
+				     int lvl, arm_lpae_iopte *ptep,
+				     unsigned long *bitmap,
+				     unsigned long base_iova,
+				     unsigned long bitmap_pgshift)
+{
+	arm_lpae_iopte pte;
+	struct io_pgtable *iop = &data->iop;
+	size_t base, next_size;
+	unsigned long offset;
+	int nbits, ret;
+
+	if (WARN_ON(lvl == ARM_LPAE_MAX_LEVELS))
+		return -EINVAL;
+
+	ptep += ARM_LPAE_LVL_IDX(iova, lvl, data);
+	pte = READ_ONCE(*ptep);
+	if (WARN_ON(!pte))
+		return -EINVAL;
+
+	if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
+		if (iopte_leaf(pte, lvl, iop->fmt)) {
+			if (pte & ARM_LPAE_PTE_AP_RDONLY)
+				return 0;
+
+			/* It is writable, set the bitmap */
+			nbits = size >> bitmap_pgshift;
+			offset = (iova - base_iova) >> bitmap_pgshift;
+			bitmap_set(bitmap, offset, nbits);
+			return 0;
+		} else {
+			/* To traverse next level */
+			next_size = ARM_LPAE_BLOCK_SIZE(lvl + 1, data);
+			ptep = iopte_deref(pte, data);
+			for (base = 0; base < size; base += next_size) {
+				ret = __arm_lpae_sync_dirty_log(data,
+						iova + base, next_size, lvl + 1,
+						ptep, bitmap, base_iova, bitmap_pgshift);
+				if (ret)
+					return ret;
+			}
+			return 0;
+		}
+	} else if (iopte_leaf(pte, lvl, iop->fmt)) {
+		if (pte & ARM_LPAE_PTE_AP_RDONLY)
+			return 0;
+
+		/* Though the size is too small, also set bitmap */
+		nbits = size >> bitmap_pgshift;
+		offset = (iova - base_iova) >> bitmap_pgshift;
+		bitmap_set(bitmap, offset, nbits);
+		return 0;
+	}
+
+	/* Keep on walkin */
+	ptep = iopte_deref(pte, data);
+	return __arm_lpae_sync_dirty_log(data, iova, size, lvl + 1, ptep,
+			bitmap, base_iova, bitmap_pgshift);
+}
+
+static int arm_lpae_sync_dirty_log(struct io_pgtable_ops *ops,
+				   unsigned long iova, size_t size,
+				   unsigned long *bitmap,
+				   unsigned long base_iova,
+				   unsigned long bitmap_pgshift)
+{
+	struct arm_lpae_io_pgtable *data = io_pgtable_ops_to_data(ops);
+	arm_lpae_iopte *ptep = data->pgd;
+	int lvl = data->start_level;
+	struct io_pgtable_cfg *cfg = &data->iop.cfg;
+	long iaext = (s64)iova >> cfg->ias;
+
+	if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size))
+		return -EINVAL;
+
+	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_TTBR1)
+		iaext = ~iaext;
+	if (WARN_ON(iaext))
+		return -EINVAL;
+
+	if (data->iop.fmt != ARM_64_LPAE_S1 &&
+	    data->iop.fmt != ARM_32_LPAE_S1)
+		return -EINVAL;
+
+	return __arm_lpae_sync_dirty_log(data, iova, size, lvl, ptep,
+					 bitmap, base_iova, bitmap_pgshift);
+}
+
 static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg *cfg)
 {
 	unsigned long granule, page_sizes;
@@ -957,6 +1046,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
 		.iova_to_phys	= arm_lpae_iova_to_phys,
 		.split_block	= arm_lpae_split_block,
 		.merge_page	= arm_lpae_merge_page,
+		.sync_dirty_log	= arm_lpae_sync_dirty_log,
 	};
 
 	return data;
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index dbee6170de7f..9e2757d12066 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -171,6 +171,10 @@ struct io_pgtable_ops {
 			      size_t size);
 	size_t (*merge_page)(struct io_pgtable_ops *ops, unsigned long iova,
 			     phys_addr_t phys, size_t size, int prot);
+	int (*sync_dirty_log)(struct io_pgtable_ops *ops,
+			      unsigned long iova, size_t size,
+			      unsigned long *bitmap, unsigned long base_iova,
+			      unsigned long bitmap_pgshift);
 };
 
 /**
-- 
2.19.1