ANDROID: KVM: arm64: Remove unused IOMMU hooks, kvm_iommu_ops

With new generic IOMMU code in place, and with all S2MPU code
having been migrated to the new pkvm_iommu_ops callbacks, remove
all the now unused code.

Bug: 190463801
Change-Id: I83a1ac7c2e30ee76712079727da4607bda5de68a
Signed-off-by: David Brazdil <dbrazdil@google.com>
(cherry picked from commit e900628cfc)
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>

arch/arm64/include/asm/kvm_host.h

@@ -379,10 +379,6 @@ extern s64 kvm_nvhe_sym(hyp_physvirt_offset);
 extern u64 kvm_nvhe_sym(hyp_cpu_logical_map)[NR_CPUS];
 #define hyp_cpu_logical_map CHOOSE_NVHE_SYM(hyp_cpu_logical_map)
 
-enum kvm_iommu_driver {
-	KVM_IOMMU_DRIVER_NONE,
-};
-
 enum pkvm_iommu_driver_id {
 	PKVM_IOMMU_DRIVER_S2MPU,
 	PKVM_IOMMU_NR_DRIVERS,

arch/arm64/include/asm/kvm_hyp.h

@@ -114,8 +114,7 @@ void __noreturn __hyp_do_panic(struct kvm_cpu_context *host_ctxt, u64 spsr,
 void __pkvm_init_switch_pgd(phys_addr_t phys, unsigned long size,
 			    phys_addr_t pgd, void *sp, void *cont_fn);
 int __pkvm_init(phys_addr_t phys, unsigned long size, unsigned long nr_cpus,
-		unsigned long *per_cpu_base, u32 hyp_va_bits,
-		enum kvm_iommu_driver iommu_driver);
+		unsigned long *per_cpu_base, u32 hyp_va_bits);
 void __noreturn __host_enter(struct kvm_cpu_context *host_ctxt);
 #endif
 

arch/arm64/kvm/arm.c

@@ -1919,11 +1919,6 @@ static bool init_psci_relay(void)
 	return true;
 }
 
-static int init_stage2_iommu(void)
-{
-	return KVM_IOMMU_DRIVER_NONE;
-}
-
 static int init_subsystems(void)
 {
 	int err = 0;
@@ -1982,7 +1977,7 @@ static void teardown_hyp_mode(void)
 	}
 }
 
-static int do_pkvm_init(u32 hyp_va_bits, enum kvm_iommu_driver iommu_driver)
+static int do_pkvm_init(u32 hyp_va_bits)
 {
 	void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
 	int ret;
@@ -1991,7 +1986,7 @@ static int do_pkvm_init(u32 hyp_va_bits, enum kvm_iommu_driver iommu_driver)
 	cpu_hyp_init_context();
 	ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
 				num_possible_cpus(), kern_hyp_va(per_cpu_base),
-				hyp_va_bits, iommu_driver);
+				hyp_va_bits);
 	cpu_hyp_init_features();
 
 	/*
@@ -2028,11 +2023,7 @@ static int kvm_hyp_init_protection(u32 hyp_va_bits)
 	if (ret)
 		return ret;
 
-	ret = init_stage2_iommu();
-	if (ret < 0)
-		return ret;
-
-	ret = do_pkvm_init(hyp_va_bits, (enum kvm_iommu_driver)ret);
+	ret = do_pkvm_init(hyp_va_bits);
 	if (ret)
 		return ret;
 

arch/arm64/kvm/hyp/include/nvhe/iommu.h

@@ -82,19 +82,4 @@ void pkvm_iommu_host_stage2_idmap(phys_addr_t start, phys_addr_t end,
 
 extern const struct pkvm_iommu_ops pkvm_s2mpu_ops;
 
-struct kvm_iommu_ops {
-	int (*init)(void);
-	bool (*host_smc_handler)(struct kvm_cpu_context *host_ctxt);
-	bool (*host_mmio_dabt_handler)(struct kvm_cpu_context *host_ctxt,
-				       phys_addr_t fault_pa, unsigned int len,
-				       bool is_write, int rd);
-	void (*host_stage2_set_owner)(phys_addr_t addr, size_t size,
-				      enum pkvm_component_id owner_id);
-	int (*host_stage2_adjust_mmio_range)(phys_addr_t addr, phys_addr_t *start,
-					     phys_addr_t *end);
-};
-
-extern struct kvm_iommu_ops kvm_iommu_ops;
-extern const struct kvm_iommu_ops kvm_s2mpu_ops;
-
 #endif	/* __ARM64_KVM_NVHE_IOMMU_H__ */

arch/arm64/kvm/hyp/nvhe/hyp-main.c

@@ -37,8 +37,6 @@ static DEFINE_PER_CPU(struct user_fpsimd_state, loaded_host_fpsimd_state);
 
 DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
 
-struct kvm_iommu_ops kvm_iommu_ops;
-
 void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt);
 
 static int pkvm_refill_memcache(struct pkvm_hyp_vcpu *hyp_vcpu)
@@ -1016,7 +1014,6 @@ static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
 	DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
 	DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
 	DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5);
-	DECLARE_REG(enum kvm_iommu_driver, iommu_driver, host_ctxt, 6);
 
 	/*
 	 * __pkvm_init() will return only if an error occurred, otherwise it
@@ -1024,7 +1021,7 @@ static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
 	 * with the host context directly.
 	 */
 	cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base,
-					    hyp_va_bits, iommu_driver);
+					    hyp_va_bits);
 }
 
 static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt)
@@ -1228,8 +1225,6 @@ static void handle_host_smc(struct kvm_cpu_context *host_ctxt)
 	bool handled;
 
 	handled = kvm_host_psci_handler(host_ctxt);
-	if (!handled && kvm_iommu_ops.host_smc_handler)
-		handled = kvm_iommu_ops.host_smc_handler(host_ctxt);
 	if (!handled)
 		handled = kvm_host_ffa_handler(host_ctxt);
 	if (!handled)

arch/arm64/kvm/hyp/nvhe/setup.c

@@ -302,16 +302,6 @@ static int fix_hyp_pgtable_refcnt(void)
 				&walker);
 }
 
-static int select_iommu_ops(enum kvm_iommu_driver driver)
-{
-	switch (driver) {
-	case KVM_IOMMU_DRIVER_NONE:
-		return 0;
-	}
-
-	return -EINVAL;
-}
-
 void __noreturn __pkvm_init_finalise(void)
 {
 	struct kvm_host_data *host_data = this_cpu_ptr(&kvm_host_data);
@@ -341,12 +331,6 @@ void __noreturn __pkvm_init_finalise(void)
 	};
 	pkvm_pgtable.mm_ops = &pkvm_pgtable_mm_ops;
 
-	if (kvm_iommu_ops.init) {
-		ret = kvm_iommu_ops.init();
-		if (ret)
-			goto out;
-	}
-
 	ret = fix_host_ownership();
 	if (ret)
 		goto out;
@@ -375,8 +359,7 @@ out:
 }
 
 int __pkvm_init(phys_addr_t phys, unsigned long size, unsigned long nr_cpus,
-		unsigned long *per_cpu_base, u32 hyp_va_bits,
-		enum kvm_iommu_driver iommu_driver)
+		unsigned long *per_cpu_base, u32 hyp_va_bits)
 {
 	struct kvm_nvhe_init_params *params;
 	void *virt = hyp_phys_to_virt(phys);
@@ -399,10 +382,6 @@ int __pkvm_init(phys_addr_t phys, unsigned long size, unsigned long nr_cpus,
 	if (ret)
 		return ret;
 
-	ret = select_iommu_ops(iommu_driver);
-	if (ret)
-		return ret;
-
 	update_nvhe_init_params();
 
 	/* Jump in the idmap page to switch to the new page-tables */