treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

4 files changed, 7 insertions, 9 deletions

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 958050c213f9..c652f16eb702 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -2258,7 +2258,7 @@ static void iommu_enable_ga(struct amd_iommu *iommu)
 	switch (amd_iommu_guest_ir) {
 	case AMD_IOMMU_GUEST_IR_VAPIC:
 		iommu_feature_enable(iommu, CONTROL_GAM_EN);
-		/* Fall through */
+		fallthrough;
 	case AMD_IOMMU_GUEST_IR_LEGACY_GA:
 		iommu_feature_enable(iommu, CONTROL_GA_EN);
 		iommu->irte_ops = &irte_128_ops;
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 7196207be7ea..c192544e874b 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -903,7 +903,7 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 		break;
 	case CMDQ_OP_CFGI_CD:
 		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SSID, ent->cfgi.ssid);
-		/* Fallthrough */
+		fallthrough;
 	case CMDQ_OP_CFGI_STE:
 		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid);
 		cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_LEAF, ent->cfgi.leaf);
@@ -936,7 +936,7 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 		break;
 	case CMDQ_OP_TLBI_NH_ASID:
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_ASID, ent->tlbi.asid);
-		/* Fallthrough */
+		fallthrough;
 	case CMDQ_OP_TLBI_S12_VMALL:
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
 		break;
@@ -1036,7 +1036,6 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
 		 */
 		return;
 	case CMDQ_ERR_CERROR_ILL_IDX:
-		/* Fallthrough */
 	default:
 		break;
 	}
@@ -3758,7 +3757,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
 	case IDR0_STALL_MODEL_FORCE:
 		smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
-		/* Fallthrough */
+		fallthrough;
 	case IDR0_STALL_MODEL_STALL:
 		smmu->features |= ARM_SMMU_FEAT_STALLS;
 	}
@@ -3778,7 +3777,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	switch (FIELD_GET(IDR0_TTF, reg)) {
 	case IDR0_TTF_AARCH32_64:
 		smmu->ias = 40;
-		/* Fallthrough */
+		fallthrough;
 	case IDR0_TTF_AARCH64:
 		break;
 	default:
@@ -3875,7 +3874,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	default:
 		dev_info(smmu->dev,
 			"unknown output address size. Truncating to 48-bit\n");
-		/* Fallthrough */
+		fallthrough;
 	case IDR5_OAS_48_BIT:
 		smmu->oas = 48;
 	}
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index e9864e52b0e9..f8177c59d229 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5070,7 +5070,6 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type)
 
 	switch (type) {
 	case IOMMU_DOMAIN_DMA:
-	/* fallthrough */
 	case IOMMU_DOMAIN_UNMANAGED:
 		dmar_domain = alloc_domain(0);
 		if (!dmar_domain) {
diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index b4da396cce60..2bfdd5734844 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -440,7 +440,7 @@ static int viommu_add_resv_mem(struct viommu_endpoint *vdev,
 	default:
 		dev_warn(vdev->dev, "unknown resv mem subtype 0x%x\n",
 			 mem->subtype);
-		/* Fall-through */
+		fallthrough;
 	case VIRTIO_IOMMU_RESV_MEM_T_RESERVED:
 		region = iommu_alloc_resv_region(start, size, 0,
 						 IOMMU_RESV_RESERVED);