[PATCH v6 04/25] iommu/arm-smmu-v3: Move TLB range invalidation into common code

[Mostafa Saleh <smostafa@google.com>]

Range TLB invalidation has a very specific algorithm. Instead of
re-writing it for the hypervisor, move it to a function that can
be re-used.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 65 ++++--------------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 76 +++++++++++++++++++++
 2 files changed, 88 insertions(+), 53 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 cb64f88989f0..c22832d26495 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2362,68 +2362,27 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 	arm_smmu_domain_inv(smmu_domain);
 }
 
+static void __arm_smmu_cmdq_batch_add(void *__opaque,
+				      struct arm_smmu_cmdq_batch *cmds,
+				      struct arm_smmu_cmdq_ent *cmd)
+{
+	struct arm_smmu_device *smmu = (struct arm_smmu_device *)__opaque;
+
+	arm_smmu_cmdq_batch_add(smmu, cmds, cmd);
+}
+
 static void arm_smmu_cmdq_batch_add_range(struct arm_smmu_device *smmu,
 					  struct arm_smmu_cmdq_batch *cmds,
 					  struct arm_smmu_cmdq_ent *cmd,
 					  unsigned long iova, size_t size,
 					  size_t granule, size_t pgsize)
 {
-	unsigned long end = iova + size, num_pages = 0, tg = pgsize;
-	size_t inv_range = granule;
-
 	if (WARN_ON_ONCE(!size))
 		return;
 
-	if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
-		num_pages = size >> tg;
-
-		/* Convert page size of 12,14,16 (log2) to 1,2,3 */
-		cmd->tlbi.tg = (tg - 10) / 2;
-
-		/*
-		 * Determine what level the granule is at. For non-leaf, both
-		 * io-pgtable and SVA pass a nominal last-level granule because
-		 * they don't know what level(s) actually apply, so ignore that
-		 * and leave TTL=0. However for various errata reasons we still
-		 * want to use a range command, so avoid the SVA corner case
-		 * where both scale and num could be 0 as well.
-		 */
-		if (cmd->tlbi.leaf)
-			cmd->tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
-		else if ((num_pages & CMDQ_TLBI_RANGE_NUM_MAX) == 1)
-			num_pages++;
-	}
-
-	while (iova < end) {
-		if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
-			/*
-			 * On each iteration of the loop, the range is 5 bits
-			 * worth of the aligned size remaining.
-			 * The range in pages is:
-			 *
-			 * range = (num_pages & (0x1f << __ffs(num_pages)))
-			 */
-			unsigned long scale, num;
-
-			/* Determine the power of 2 multiple number of pages */
-			scale = __ffs(num_pages);
-			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;
-
-			/* range is num * 2^scale * pgsize */
-			inv_range = num << (scale + tg);
-
-			/* Clear out the lower order bits for the next iteration */
-			num_pages -= num << scale;
-		}
-
-		cmd->tlbi.addr = iova;
-		arm_smmu_cmdq_batch_add(smmu, cmds, cmd);
-		iova += inv_range;
-	}
+	arm_smmu_tlb_inv_build(cmd, iova, size, granule,
+			       pgsize, smmu->features & ARM_SMMU_FEAT_RANGE_INV,
+			       smmu, __arm_smmu_cmdq_batch_add, cmds);
 }
 
 static bool arm_smmu_inv_size_too_big(struct arm_smmu_device *smmu, size_t size,
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 9b8c5fb7282b..7be41dbe5aaa 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -1204,6 +1204,82 @@ static inline void arm_smmu_write_strtab_l1_desc(struct arm_smmu_strtab_l1 *dst,
 	WRITE_ONCE(dst->l2ptr, cpu_to_le64(val));
 }
 
+/**
+ * arm_smmu_tlb_inv_build - Create a range invalidation command
+ * @cmd: Base command initialized with OPCODE (S1, S2..), vmid and asid
+ * @iova: Start IOVA to invalidate
+ * @size: Size of range
+ * @granule: Granule of invalidation
+ * @pgsize: Page size of the invalidation
+ * @is_range: Use range invalidation commands
+ * @opaque: Pointer to pass to add_cmd
+ * @add_cmd: Function to send/batch the invalidation command
+ * @cmds: Incase of batching, it includes the pointer to the batch
+ */
+static inline void arm_smmu_tlb_inv_build(struct arm_smmu_cmdq_ent *cmd,
+					  unsigned long iova, size_t size,
+					  size_t granule, unsigned long pgsize,
+					  bool is_range, void *opaque,
+					  void (*add_cmd)(void *_opaque,
+							  struct arm_smmu_cmdq_batch *cmds,
+							  struct arm_smmu_cmdq_ent *cmd),
+					  struct arm_smmu_cmdq_batch *cmds)
+{
+	unsigned long end = iova + size, num_pages = 0, tg = pgsize;
+	size_t inv_range = granule;
+
+	if (is_range) {
+		num_pages = size >> tg;
+
+		/* Convert page size of 12,14,16 (log2) to 1,2,3 */
+		cmd->tlbi.tg = (tg - 10) / 2;
+
+		/*
+		 * Determine what level the granule is at. For non-leaf, both
+		 * io-pgtable and SVA pass a nominal last-level granule because
+		 * they don't know what level(s) actually apply, so ignore that
+		 * and leave TTL=0. However for various errata reasons we still
+		 * want to use a range command, so avoid the SVA corner case
+		 * where both scale and num could be 0 as well.
+		 */
+		if (cmd->tlbi.leaf)
+			cmd->tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
+		else if ((num_pages & CMDQ_TLBI_RANGE_NUM_MAX) == 1)
+			num_pages++;
+	}
+
+	while (iova < end) {
+		if (is_range) {
+			/*
+			 * On each iteration of the loop, the range is 5 bits
+			 * worth of the aligned size remaining.
+			 * The range in pages is:
+			 *
+			 * range = (num_pages & (0x1f << __ffs(num_pages)))
+			 */
+			unsigned long scale, num;
+
+			/* Determine the power of 2 multiple number of pages */
+			scale = __ffs(num_pages);
+			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;
+
+			/* range is num * 2^scale * pgsize */
+			inv_range = num << (scale + tg);
+
+			/* Clear out the lower order bits for the next iteration */
+			num_pages -= num << scale;
+		}
+
+		cmd->tlbi.addr = iova;
+		add_cmd(opaque, cmds, cmd);
+		iova += inv_range;
+	}
+}
+
 #ifdef CONFIG_ARM_SMMU_V3_SVA
 bool arm_smmu_sva_supported(struct arm_smmu_device *smmu);
 void arm_smmu_sva_notifier_synchronize(void);
-- 
2.54.0.545.g6539524ca2-goog