iommu/arm-smmu-v3: Split arm_smmu_tlb_inv_range()

Extract some of the cmd initialization and the ATC invalidation from
arm_smmu_tlb_inv_range(), to allow an MMU notifier to invalidate a VA
range by ASID.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20210122151054.2833521-2-jean-philippe@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>

Author: Jean-Philippe Brucker

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

@@ -1658,40 +1658,28 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 	arm_smmu_atc_inv_domain(smmu_domain, 0, 0, 0);
 }
 
-static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
-				   size_t granule, bool leaf,
-				   struct arm_smmu_domain *smmu_domain)
+static void __arm_smmu_tlb_inv_range(struct arm_smmu_cmdq_ent *cmd,
+				     unsigned long iova, size_t size,
+				     size_t granule,
+				     struct arm_smmu_domain *smmu_domain)
 {
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	unsigned long start = iova, end = iova + size, num_pages = 0, tg = 0;
+	unsigned long end = iova + size, num_pages = 0, tg = 0;
 	size_t inv_range = granule;
 	struct arm_smmu_cmdq_batch cmds = {};
-	struct arm_smmu_cmdq_ent cmd = {
-		.tlbi = {
-			.leaf	= leaf,
-		},
-	};
 
 	if (!size)
 		return;
 
-	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-		cmd.opcode	= CMDQ_OP_TLBI_NH_VA;
-		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
-	} else {
-		cmd.opcode	= CMDQ_OP_TLBI_S2_IPA;
-		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
-	}
-
 	if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
 		/* Get the leaf page size */
 		tg = __ffs(smmu_domain->domain.pgsize_bitmap);
 
 		/* Convert page size of 12,14,16 (log2) to 1,2,3 */
-		cmd.tlbi.tg = (tg - 10) / 2;
+		cmd->tlbi.tg = (tg - 10) / 2;
 
 		/* Determine what level the granule is at */
-		cmd.tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
+		cmd->tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
 
 		num_pages = size >> tg;
 	}
@@ -1709,11 +1697,11 @@ static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
 
 			/* Determine the power of 2 multiple number of pages */
 			scale = __ffs(num_pages);
-			cmd.tlbi.scale = scale;
+			cmd->tlbi.scale = scale;
 
 			/* Determine how many chunks of 2^scale size we have */
 			num = (num_pages >> scale) & CMDQ_TLBI_RANGE_NUM_MAX;
-			cmd.tlbi.num = num - 1;
+			cmd->tlbi.num = num - 1;
 
 			/* range is num * 2^scale * pgsize */
 			inv_range = num << (scale + tg);
@@ -1722,17 +1710,37 @@ static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
 			num_pages -= num << scale;
 		}
 
-		cmd.tlbi.addr = iova;
-		arm_smmu_cmdq_batch_add(smmu, &cmds, &cmd);
+		cmd->tlbi.addr = iova;
+		arm_smmu_cmdq_batch_add(smmu, &cmds, cmd);
 		iova += inv_range;
 	}
 	arm_smmu_cmdq_batch_submit(smmu, &cmds);
+}
+
+static void arm_smmu_tlb_inv_range_domain(unsigned long iova, size_t size,
+					  size_t granule, bool leaf,
+					  struct arm_smmu_domain *smmu_domain)
+{
+	struct arm_smmu_cmdq_ent cmd = {
+		.tlbi = {
+			.leaf	= leaf,
+		},
+	};
+
+	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
+		cmd.opcode	= CMDQ_OP_TLBI_NH_VA;
+		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
+	} else {
+		cmd.opcode	= CMDQ_OP_TLBI_S2_IPA;
+		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
+	}
+	__arm_smmu_tlb_inv_range(&cmd, iova, size, granule, smmu_domain);
 
 	/*
 	 * Unfortunately, this can't be leaf-only since we may have
 	 * zapped an entire table.
 	 */
-	arm_smmu_atc_inv_domain(smmu_domain, 0, start, size);
+	arm_smmu_atc_inv_domain(smmu_domain, 0, iova, size);
 }
 
 static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
@@ -1748,7 +1756,7 @@ static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
 static void arm_smmu_tlb_inv_walk(unsigned long iova, size_t size,
 				  size_t granule, void *cookie)
 {
-	arm_smmu_tlb_inv_range(iova, size, granule, false, cookie);
+	arm_smmu_tlb_inv_range_domain(iova, size, granule, false, cookie);
 }
 
 static const struct iommu_flush_ops arm_smmu_flush_ops = {
@@ -2271,8 +2279,9 @@ static void arm_smmu_iotlb_sync(struct iommu_domain *domain,
 {
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 
-	arm_smmu_tlb_inv_range(gather->start, gather->end - gather->start,
-			       gather->pgsize, true, smmu_domain);
+	arm_smmu_tlb_inv_range_domain(gather->start,
+				      gather->end - gather->start,
+				      gather->pgsize, true, smmu_domain);
 }
 
 static phys_addr_t