From patchwork Fri Apr 12 08:42:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 13627194 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id BCCA2537EE; Fri, 12 Apr 2024 08:43:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712911421; cv=none; b=bRv00sXLObTvgYxBmWzwWrubio2ZtnbF6waqise3h1z7tUrYAyUFNRlc1vRBNJaFjIaddk6bfZSF30KmB9S2Bcoh62KCjhZni1m5A11KU3NC2ugCUfeg2Ko90rQnH9FzReFOkJ9bjrvYUKG6sbRDXlWY0NtKTf3W17mrZmXiuiY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712911421; c=relaxed/simple; bh=T2RRS0P6A/c9k2qicGz7O5TImAsfjNLSkD8GFYlVmQ8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=h5lWyYCzV7pa973yuonWLWYEeTQY+sm1C+2NwKGXuJdHUPqlCWcYnvObwZW6mY35wqj2FcCsDZQrGbFc/2Jp3dnF8SJj7xZ/n0hRUzUKNiR/7m6sFblYxcvZ1bWHjFjU9gYXBprs7ulocaAbINvnn+9Cq83owr7uwFmvnrtjNMQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A6045339; Fri, 12 Apr 2024 01:44:08 -0700 (PDT) Received: from e112269-lin.cambridge.arm.com (e112269-lin.cambridge.arm.com [10.1.194.51]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2FFA03F6C4; Fri, 12 Apr 2024 01:43:37 -0700 (PDT) From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Jean-Philippe Brucker Subject: [PATCH v2 09/43] arm64: RME: ioctls to create and configure realms Date: Fri, 12 Apr 2024 09:42:35 +0100 Message-Id: <20240412084309.1733783-10-steven.price@arm.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240412084309.1733783-1-steven.price@arm.com> References: <20240412084056.1733704-1-steven.price@arm.com> <20240412084309.1733783-1-steven.price@arm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add the KVM_CAP_ARM_RME_CREATE_FD ioctl to create a realm. This involves delegating pages to the RMM to hold the Realm Descriptor (RD) and for the base level of the Realm Translation Tables (RTT). A VMID also need to be picked, since the RMM has a separate VMID address space a dedicated allocator is added for this purpose. KVM_CAP_ARM_RME_CONFIG_REALM is provided to allow configuring the realm before it is created. Co-developed-by: Suzuki K Poulose Signed-off-by: Suzuki K Poulose Signed-off-by: Steven Price Signed-off-by: Jean-Philippe Brucker --- arch/arm64/include/asm/kvm_emulate.h | 5 + arch/arm64/include/asm/kvm_rme.h | 19 ++ arch/arm64/kvm/arm.c | 18 ++ arch/arm64/kvm/mmu.c | 15 +- arch/arm64/kvm/rme.c | 282 +++++++++++++++++++++++++++ 5 files changed, 337 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 6f08398537e2..c606316f4729 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -624,6 +624,11 @@ static inline enum realm_state kvm_realm_state(struct kvm *kvm) return READ_ONCE(kvm->arch.realm.state); } +static inline bool kvm_realm_is_created(struct kvm *kvm) +{ + return kvm_is_realm(kvm) && kvm_realm_state(kvm) != REALM_STATE_NONE; +} + static inline bool vcpu_is_rec(struct kvm_vcpu *vcpu) { return false; diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h index 922da3f47227..cf8cc4d30364 100644 --- a/arch/arm64/include/asm/kvm_rme.h +++ b/arch/arm64/include/asm/kvm_rme.h @@ -6,6 +6,8 @@ #ifndef __ASM_KVM_RME_H #define __ASM_KVM_RME_H +#include + /** * enum realm_state - State of a Realm */ @@ -46,11 +48,28 @@ enum realm_state { * struct realm - Additional per VM data for a Realm * * @state: The lifetime state machine for the realm + * @rd: Kernel mapping of the Realm Descriptor (RD) + * @params: Parameters for the RMI_REALM_CREATE command + * @num_aux: The number of auxiliary pages required by the RMM + * @vmid: VMID to be used by the RMM for the realm + * @ia_bits: Number of valid Input Address bits in the IPA */ struct realm { enum realm_state state; + + void *rd; + struct realm_params *params; + + unsigned long num_aux; + unsigned int vmid; + unsigned int ia_bits; }; int kvm_init_rme(void); +u32 kvm_realm_ipa_limit(void); + +int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap); +int kvm_init_realm_vm(struct kvm *kvm); +void kvm_destroy_realm(struct kvm *kvm); #endif diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 2056c660c5ee..5729ea430d6d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -119,6 +119,13 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, } mutex_unlock(&kvm->slots_lock); break; + case KVM_CAP_ARM_RME: + if (!kvm_is_realm(kvm)) + return -EINVAL; + mutex_lock(&kvm->lock); + r = kvm_realm_enable_cap(kvm, cap); + mutex_unlock(&kvm->lock); + break; default: r = -EINVAL; break; @@ -179,6 +186,13 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES); + /* Initialise the realm bits after the generic bits are enabled */ + if (kvm_is_realm(kvm)) { + ret = kvm_init_realm_vm(kvm); + if (ret) + goto err_free_cpumask; + } + return 0; err_free_cpumask: @@ -219,6 +233,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm) kvm_unshare_hyp(kvm, kvm + 1); kvm_arm_teardown_hypercalls(kvm); + kvm_destroy_realm(kvm); } int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) @@ -328,6 +343,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES: r = BIT(0); break; + case KVM_CAP_ARM_RME: + r = static_key_enabled(&kvm_rme_is_available); + break; default: r = 0; } diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 18680771cdb0..aae365647b62 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -872,6 +872,10 @@ int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long t struct kvm_pgtable *pgt; u64 mmfr0, mmfr1; u32 phys_shift; + u32 ipa_limit = kvm_ipa_limit; + + if (kvm_is_realm(kvm)) + ipa_limit = kvm_realm_ipa_limit(); if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK) return -EINVAL; @@ -880,12 +884,12 @@ int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long t if (is_protected_kvm_enabled()) { phys_shift = kvm_ipa_limit; } else if (phys_shift) { - if (phys_shift > kvm_ipa_limit || + if (phys_shift > ipa_limit || phys_shift < ARM64_MIN_PARANGE_BITS) return -EINVAL; } else { phys_shift = KVM_PHYS_SHIFT; - if (phys_shift > kvm_ipa_limit) { + if (phys_shift > ipa_limit) { pr_warn_once("%s using unsupported default IPA limit, upgrade your VMM\n", current->comm); return -EINVAL; @@ -1014,6 +1018,13 @@ void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu) struct kvm_pgtable *pgt = NULL; write_lock(&kvm->mmu_lock); + if (kvm_is_realm(kvm) && + (kvm_realm_state(kvm) != REALM_STATE_DEAD && + kvm_realm_state(kvm) != REALM_STATE_NONE)) { + /* TODO: teardown rtts */ + write_unlock(&kvm->mmu_lock); + return; + } pgt = mmu->pgt; if (pgt) { mmu->pgd_phys = 0; diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c index 3dbbf9d046bf..658d14e8d87d 100644 --- a/arch/arm64/kvm/rme.c +++ b/arch/arm64/kvm/rme.c @@ -5,9 +5,20 @@ #include +#include +#include #include #include +#include + +static unsigned long rmm_feat_reg0; + +static bool rme_supports(unsigned long feature) +{ + return !!u64_get_bits(rmm_feat_reg0, feature); +} + static int rmi_check_version(void) { struct arm_smccc_res res; @@ -36,8 +47,272 @@ static int rmi_check_version(void) return 0; } +u32 kvm_realm_ipa_limit(void) +{ + return u64_get_bits(rmm_feat_reg0, RMI_FEATURE_REGISTER_0_S2SZ); +} + +static int get_start_level(struct realm *realm) +{ + return 4 - stage2_pgtable_levels(realm->ia_bits); +} + +static int realm_create_rd(struct kvm *kvm) +{ + struct realm *realm = &kvm->arch.realm; + struct realm_params *params = realm->params; + void *rd = NULL; + phys_addr_t rd_phys, params_phys; + struct kvm_pgtable *pgt = kvm->arch.mmu.pgt; + int i, r; + + if (WARN_ON(realm->rd) || WARN_ON(!realm->params)) + return -EEXIST; + + rd = (void *)__get_free_page(GFP_KERNEL); + if (!rd) + return -ENOMEM; + + rd_phys = virt_to_phys(rd); + if (rmi_granule_delegate(rd_phys)) { + r = -ENXIO; + goto out; + } + + for (i = 0; i < pgt->pgd_pages; i++) { + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i * PAGE_SIZE; + + if (rmi_granule_delegate(pgd_phys)) { + r = -ENXIO; + goto out_undelegate_tables; + } + } + + realm->ia_bits = VTCR_EL2_IPA(kvm->arch.mmu.vtcr); + + params->rtt_level_start = get_start_level(realm); + params->rtt_num_start = pgt->pgd_pages; + params->rtt_base = kvm->arch.mmu.pgd_phys; + params->vmid = realm->vmid; + + params_phys = virt_to_phys(params); + + if (rmi_realm_create(rd_phys, params_phys)) { + r = -ENXIO; + goto out_undelegate_tables; + } + + realm->rd = rd; + + if (WARN_ON(rmi_rec_aux_count(rd_phys, &realm->num_aux))) { + WARN_ON(rmi_realm_destroy(rd_phys)); + goto out_undelegate_tables; + } + + return 0; + +out_undelegate_tables: + while (--i >= 0) { + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i * PAGE_SIZE; + + WARN_ON(rmi_granule_undelegate(pgd_phys)); + } + WARN_ON(rmi_granule_undelegate(rd_phys)); +out: + free_page((unsigned long)rd); + return r; +} + +/* Protects access to rme_vmid_bitmap */ +static DEFINE_SPINLOCK(rme_vmid_lock); +static unsigned long *rme_vmid_bitmap; + +static int rme_vmid_init(void) +{ + unsigned int vmid_count = 1 << kvm_get_vmid_bits(); + + rme_vmid_bitmap = bitmap_zalloc(vmid_count, GFP_KERNEL); + if (!rme_vmid_bitmap) { + kvm_err("%s: Couldn't allocate rme vmid bitmap\n", __func__); + return -ENOMEM; + } + + return 0; +} + +static int rme_vmid_reserve(void) +{ + int ret; + unsigned int vmid_count = 1 << kvm_get_vmid_bits(); + + spin_lock(&rme_vmid_lock); + ret = bitmap_find_free_region(rme_vmid_bitmap, vmid_count, 0); + spin_unlock(&rme_vmid_lock); + + return ret; +} + +static void rme_vmid_release(unsigned int vmid) +{ + spin_lock(&rme_vmid_lock); + bitmap_release_region(rme_vmid_bitmap, vmid, 0); + spin_unlock(&rme_vmid_lock); +} + +static int kvm_create_realm(struct kvm *kvm) +{ + struct realm *realm = &kvm->arch.realm; + int ret; + + if (!kvm_is_realm(kvm) || kvm_realm_is_created(kvm)) + return -EEXIST; + + ret = rme_vmid_reserve(); + if (ret < 0) + return ret; + realm->vmid = ret; + + ret = realm_create_rd(kvm); + if (ret) { + rme_vmid_release(realm->vmid); + return ret; + } + + WRITE_ONCE(realm->state, REALM_STATE_NEW); + + /* The realm is up, free the parameters. */ + free_page((unsigned long)realm->params); + realm->params = NULL; + + return 0; +} + +static int config_realm_hash_algo(struct realm *realm, + struct kvm_cap_arm_rme_config_item *cfg) +{ + switch (cfg->hash_algo) { + case KVM_CAP_ARM_RME_MEASUREMENT_ALGO_SHA256: + if (!rme_supports(RMI_FEATURE_REGISTER_0_HASH_SHA_256)) + return -EINVAL; + break; + case KVM_CAP_ARM_RME_MEASUREMENT_ALGO_SHA512: + if (!rme_supports(RMI_FEATURE_REGISTER_0_HASH_SHA_512)) + return -EINVAL; + break; + default: + return -EINVAL; + } + realm->params->hash_algo = cfg->hash_algo; + return 0; +} + +static int kvm_rme_config_realm(struct kvm *kvm, struct kvm_enable_cap *cap) +{ + struct kvm_cap_arm_rme_config_item cfg; + struct realm *realm = &kvm->arch.realm; + int r = 0; + + if (kvm_realm_is_created(kvm)) + return -EINVAL; + + if (copy_from_user(&cfg, (void __user *)cap->args[1], sizeof(cfg))) + return -EFAULT; + + switch (cfg.cfg) { + case KVM_CAP_ARM_RME_CFG_RPV: + memcpy(&realm->params->rpv, &cfg.rpv, sizeof(cfg.rpv)); + break; + case KVM_CAP_ARM_RME_CFG_HASH_ALGO: + r = config_realm_hash_algo(realm, &cfg); + break; + default: + r = -EINVAL; + } + + return r; +} + +int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) +{ + int r = 0; + + if (!kvm_is_realm(kvm)) + return -EINVAL; + + switch (cap->args[0]) { + case KVM_CAP_ARM_RME_CONFIG_REALM: + r = kvm_rme_config_realm(kvm, cap); + break; + case KVM_CAP_ARM_RME_CREATE_RD: + r = kvm_create_realm(kvm); + break; + default: + r = -EINVAL; + break; + } + + return r; +} + +void kvm_destroy_realm(struct kvm *kvm) +{ + struct realm *realm = &kvm->arch.realm; + struct kvm_pgtable *pgt = kvm->arch.mmu.pgt; + int i; + + if (realm->params) { + free_page((unsigned long)realm->params); + realm->params = NULL; + } + + if (!kvm_realm_is_created(kvm)) + return; + + WRITE_ONCE(realm->state, REALM_STATE_DYING); + + if (realm->rd) { + phys_addr_t rd_phys = virt_to_phys(realm->rd); + + if (WARN_ON(rmi_realm_destroy(rd_phys))) + return; + if (WARN_ON(rmi_granule_undelegate(rd_phys))) + return; + free_page((unsigned long)realm->rd); + realm->rd = NULL; + } + + rme_vmid_release(realm->vmid); + + for (i = 0; i < pgt->pgd_pages; i++) { + phys_addr_t pgd_phys = kvm->arch.mmu.pgd_phys + i * PAGE_SIZE; + + if (WARN_ON(rmi_granule_undelegate(pgd_phys))) + return; + } + + WRITE_ONCE(realm->state, REALM_STATE_DEAD); + + kvm_free_stage2_pgd(&kvm->arch.mmu); +} + +int kvm_init_realm_vm(struct kvm *kvm) +{ + struct realm_params *params; + + params = (struct realm_params *)get_zeroed_page(GFP_KERNEL); + if (!params) + return -ENOMEM; + + /* Default parameters, not exposed to user space */ + params->s2sz = VTCR_EL2_IPA(kvm->arch.mmu.vtcr); + kvm->arch.realm.params = params; + return 0; +} + int kvm_init_rme(void) { + int ret; + if (PAGE_SIZE != SZ_4K) /* Only 4k page size on the host is supported */ return 0; @@ -46,6 +321,13 @@ int kvm_init_rme(void) /* Continue without realm support */ return 0; + if (WARN_ON(rmi_features(0, &rmm_feat_reg0))) + return 0; + + ret = rme_vmid_init(); + if (ret) + return ret; + /* Future patch will enable static branch kvm_rme_is_available */ return 0;