[RFC PATCH v2 32/58] KVM: arm64: smmu-v3: Add {alloc/free}_domain

[Mostafa Saleh <smostafa@google.com>]

Add SMMUv3 alloc/free domain, as this operations are not
tied to the IOMMU, we can't do much with the io-pgtable
allocation or configuration.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
---
 arch/arm64/kvm/hyp/nvhe/iommu/arm-smmu-v3.c | 64 +++++++++++++++++++++
 include/kvm/arm_smmu_v3.h                   |  6 ++
 2 files changed, 70 insertions(+)

diff --git a/arch/arm64/kvm/hyp/nvhe/iommu/arm-smmu-v3.c b/arch/arm64/kvm/hyp/nvhe/iommu/arm-smmu-v3.c
index 58662c2c4c97..3181933e9a34 100644
--- a/arch/arm64/kvm/hyp/nvhe/iommu/arm-smmu-v3.c
+++ b/arch/arm64/kvm/hyp/nvhe/iommu/arm-smmu-v3.c
@@ -7,6 +7,8 @@
 #include <asm/arm-smmu-v3-common.h>
 #include <asm/kvm_hyp.h>
 #include <kvm/arm_smmu_v3.h>
+#include <linux/io-pgtable-arm.h>
+#include <nvhe/alloc.h>
 #include <nvhe/iommu.h>
 #include <nvhe/mem_protect.h>
 #include <nvhe/mm.h>
@@ -50,6 +52,22 @@ struct hyp_arm_smmu_v3_device *kvm_hyp_arm_smmu_v3_smmus;
 	smmu_wait(_cond);					\
 })
 
+/*
+ * SMMUv3 domain:
+ * @domain: Pointer to the IOMMU domain.
+ * @smmu: SMMU instance for this domain.
+ * @type: Type of domain (S1, S2)
+ * @pgt_lock: Lock for page table
+ * @pgtable: io_pgtable instance for this domain
+ */
+struct hyp_arm_smmu_v3_domain {
+	struct kvm_hyp_iommu_domain     *domain;
+	struct hyp_arm_smmu_v3_device	*smmu;
+	u32				type;
+	hyp_spinlock_t			pgt_lock;
+	struct io_pgtable		*pgtable;
+};
+
 static int smmu_write_cr0(struct hyp_arm_smmu_v3_device *smmu, u32 val)
 {
 	writel_relaxed(val, smmu->base + ARM_SMMU_CR0);
@@ -541,7 +559,53 @@ static int smmu_init(void)
 	return ret;
 }
 
+static struct kvm_hyp_iommu *smmu_id_to_iommu(pkvm_handle_t smmu_id)
+{
+	if (smmu_id >= kvm_hyp_arm_smmu_v3_count)
+		return NULL;
+	smmu_id = array_index_nospec(smmu_id, kvm_hyp_arm_smmu_v3_count);
+
+	return &kvm_hyp_arm_smmu_v3_smmus[smmu_id].iommu;
+}
+
+static int smmu_alloc_domain(struct kvm_hyp_iommu_domain *domain, int type)
+{
+	struct hyp_arm_smmu_v3_domain *smmu_domain;
+
+	if (type >= KVM_ARM_SMMU_DOMAIN_MAX)
+		return -EINVAL;
+
+	smmu_domain = hyp_alloc(sizeof(*smmu_domain));
+	if (!smmu_domain)
+		return -ENOMEM;
+
+	/*
+	 * Can't do much without knowing the SMMUv3.
+	 * Page table will be allocated at attach_dev, but can be
+	 * freed from free domain.
+	 */
+	smmu_domain->domain = domain;
+	smmu_domain->type = type;
+	hyp_spin_lock_init(&smmu_domain->pgt_lock);
+	domain->priv = (void *)smmu_domain;
+
+	return 0;
+}
+
+static void smmu_free_domain(struct kvm_hyp_iommu_domain *domain)
+{
+	struct hyp_arm_smmu_v3_domain *smmu_domain = domain->priv;
+
+	if (smmu_domain->pgtable)
+		kvm_arm_io_pgtable_free(smmu_domain->pgtable);
+
+	hyp_free(smmu_domain);
+}
+
 /* Shared with the kernel driver in EL1 */
 struct kvm_iommu_ops smmu_ops = {
 	.init				= smmu_init,
+	.get_iommu_by_id		= smmu_id_to_iommu,
+	.alloc_domain			= smmu_alloc_domain,
+	.free_domain			= smmu_free_domain,
 };
diff --git a/include/kvm/arm_smmu_v3.h b/include/kvm/arm_smmu_v3.h
index 352c1b2dc72a..ded98cbaebc1 100644
--- a/include/kvm/arm_smmu_v3.h
+++ b/include/kvm/arm_smmu_v3.h
@@ -33,4 +33,10 @@ extern size_t kvm_nvhe_sym(kvm_hyp_arm_smmu_v3_count);
 extern struct hyp_arm_smmu_v3_device *kvm_nvhe_sym(kvm_hyp_arm_smmu_v3_smmus);
 #define kvm_hyp_arm_smmu_v3_smmus kvm_nvhe_sym(kvm_hyp_arm_smmu_v3_smmus)
 
+enum kvm_arm_smmu_domain_type {
+	KVM_ARM_SMMU_DOMAIN_S1,
+	KVM_ARM_SMMU_DOMAIN_S2,
+	KVM_ARM_SMMU_DOMAIN_MAX,
+};
+
 #endif /* __KVM_ARM_SMMU_V3_H */
-- 
2.47.0.338.g60cca15819-goog