[PATCH v8 12/29] iommu/smmuv3: Dynamically allocate s1_cfg and s2_cfg

[Eric Auger]

In preparation for the introduction of nested configuration
let's turn s1_cfg and s2_cfg fields into pointers which are
dynamically allocated depending on the smmu_domain stage.

In nested mode, s1_cfg will only be allocated when setting up
S1 translation.

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
 drivers/iommu/arm-smmu-v3.c | 88 +++++++++++++++++++++----------------
 1 file changed, 49 insertions(+), 39 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 1c9f0444a81b..7be509ed86d9 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -634,10 +634,8 @@ struct arm_smmu_domain {
 	bool				non_strict;
 
 	enum arm_smmu_domain_stage	stage;
-	union {
-		struct arm_smmu_s1_cfg	s1_cfg;
-		struct arm_smmu_s2_cfg	s2_cfg;
-	};
+	struct arm_smmu_s1_cfg		*s1_cfg;
+	struct arm_smmu_s2_cfg		*s2_cfg;
 
 	struct iommu_domain		domain;
 
@@ -1165,17 +1163,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 	}
 
 	if (smmu_domain) {
-		switch (smmu_domain->stage) {
-		case ARM_SMMU_DOMAIN_S1:
-			s1_cfg = &smmu_domain->s1_cfg;
-			break;
-		case ARM_SMMU_DOMAIN_S2:
-		case ARM_SMMU_DOMAIN_NESTED:
-			s2_cfg = &smmu_domain->s2_cfg;
-			break;
-		default:
-			break;
-		}
+		s1_cfg = smmu_domain->s1_cfg;
+		s2_cfg = smmu_domain->s2_cfg;
 	}
 
 	if (val & STRTAB_STE_0_V) {
@@ -1587,11 +1576,11 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 
 	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
 		cmd.opcode	= CMDQ_OP_TLBI_NH_ASID;
-		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
+		cmd.tlbi.asid	= smmu_domain->s1_cfg->cd.asid;
 		cmd.tlbi.vmid	= 0;
 	} else {
 		cmd.opcode	= CMDQ_OP_TLBI_S12_VMALL;
-		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
+		cmd.tlbi.vmid	= smmu_domain->s2_cfg->vmid;
 	}
 
 	/*
@@ -1618,10 +1607,10 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
 
 	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
 		cmd.opcode	= CMDQ_OP_TLBI_NH_VA;
-		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
+		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;
+		cmd.tlbi.vmid	= smmu_domain->s2_cfg->vmid;
 	}
 
 	do {
@@ -1702,26 +1691,29 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 {
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_s1_cfg *s1_cfg = smmu_domain->s1_cfg;
+	struct arm_smmu_s2_cfg *s2_cfg = smmu_domain->s2_cfg;
 
 	iommu_put_dma_cookie(domain);
 	free_io_pgtable_ops(smmu_domain->pgtbl_ops);
 
-	/* Free the CD and ASID, if we allocated them */
-	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-		struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
-
-		if (cfg->cdptr) {
+	if (s1_cfg) {
+		/* Free the CD and ASID, if we allocated them */
+		if (s1_cfg->cdptr) {
 			dmam_free_coherent(smmu_domain->smmu->dev,
 					   CTXDESC_CD_DWORDS << 3,
-					   cfg->cdptr,
-					   cfg->cdptr_dma);
+					   s1_cfg->cdptr,
+					   s1_cfg->cdptr_dma);
 
-			arm_smmu_bitmap_free(smmu->asid_map, cfg->cd.asid);
+			arm_smmu_bitmap_free(smmu->asid_map,
+					     s1_cfg->cd.asid);
 		}
-	} else {
-		struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
-		if (cfg->vmid)
-			arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
+		kfree(s1_cfg);
+	}
+	if (s2_cfg) {
+		if (s2_cfg->vmid)
+			arm_smmu_bitmap_free(smmu->vmid_map, s2_cfg->vmid);
+		kfree(s2_cfg);
 	}
 
 	kfree(smmu_domain);
@@ -1733,11 +1725,16 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
 	int ret;
 	int asid;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
+	struct arm_smmu_s1_cfg *cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
+
+	if (!cfg)
+		return -ENOMEM;
 
 	asid = arm_smmu_bitmap_alloc(smmu->asid_map, smmu->asid_bits);
-	if (asid < 0)
-		return asid;
+	if (asid < 0) {
+		ret = asid;
+		goto out_free_cfg;
+	}
 
 	cfg->cdptr = dmam_alloc_coherent(smmu->dev, CTXDESC_CD_DWORDS << 3,
 					 &cfg->cdptr_dma,
@@ -1752,28 +1749,41 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
 	cfg->cd.ttbr	= pgtbl_cfg->arm_lpae_s1_cfg.ttbr[0];
 	cfg->cd.tcr	= pgtbl_cfg->arm_lpae_s1_cfg.tcr;
 	cfg->cd.mair	= pgtbl_cfg->arm_lpae_s1_cfg.mair[0];
+	smmu_domain->s1_cfg = cfg;
 	return 0;
 
 out_free_asid:
 	arm_smmu_bitmap_free(smmu->asid_map, asid);
+out_free_cfg:
+	kfree(cfg);
 	return ret;
 }
 
 static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
 				       struct io_pgtable_cfg *pgtbl_cfg)
 {
-	int vmid;
+	int vmid, ret;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
+	struct arm_smmu_s2_cfg *cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
+
+	if (!cfg)
+		return -ENOMEM;
 
 	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
-	if (vmid < 0)
-		return vmid;
+	if (vmid < 0) {
+		ret = vmid;
+		goto out_free_cfg;
+	}
 
 	cfg->vmid	= (u16)vmid;
 	cfg->vttbr	= pgtbl_cfg->arm_lpae_s2_cfg.vttbr;
 	cfg->vtcr	= pgtbl_cfg->arm_lpae_s2_cfg.vtcr;
+	smmu_domain->s2_cfg = cfg;
 	return 0;
+
+out_free_cfg:
+	kfree(cfg);
+	return ret;
 }
 
 static int arm_smmu_domain_finalise(struct iommu_domain *domain)
@@ -1992,7 +2002,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 		arm_smmu_enable_ats(master);
 
 	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1)
-		arm_smmu_write_ctx_desc(smmu, &smmu_domain->s1_cfg);
+		arm_smmu_write_ctx_desc(smmu, smmu_domain->s1_cfg);
 
 	arm_smmu_install_ste_for_dev(master);
 out_unlock:
-- 
2.20.1