[PATCH 28/89] KVM: arm64: Consolidate stage-2 init in one function
Will Deacon
will at kernel.org
Thu May 19 06:41:03 PDT 2022
From: Quentin Perret <qperret at google.com>
The initialization of stage-2 page-tables of guests is currently split
across two functions: kvm_init_stage2_mmu() and kvm_arm_setup_stage2().
That is presumably for historical reasons as kvm_arm_setup_stage2()
originates from the (now defunct) KVM port for 32bit Arm.
Simplify this code path by merging both functions into one, and while at
it make sure to map the kvm struct into the hypervisor stage-1 early on
to simplify the failure path.
Signed-off-by: Quentin Perret <qperret at google.com>
---
arch/arm64/include/asm/kvm_arm.h | 2 +-
arch/arm64/include/asm/kvm_host.h | 2 --
arch/arm64/include/asm/kvm_mmu.h | 2 +-
arch/arm64/kvm/arm.c | 27 +++++++++++++--------------
arch/arm64/kvm/mmu.c | 27 ++++++++++++++++++++++++++-
arch/arm64/kvm/reset.c | 29 -----------------------------
6 files changed, 41 insertions(+), 48 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 1767ded83888..98b60fa86853 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -134,7 +134,7 @@
* 40 bits wide (T0SZ = 24). Systems with a PARange smaller than 40 bits are
* not known to exist and will break with this configuration.
*
- * The VTCR_EL2 is configured per VM and is initialised in kvm_arm_setup_stage2().
+ * The VTCR_EL2 is configured per VM and is initialised in kvm_init_stage2_mmu.
*
* Note that when using 4K pages, we concatenate two first level page tables
* together. With 16K pages, we concatenate 16 first level page tables.
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 264b1d2c4eb6..3c6ed1f3887d 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -865,8 +865,6 @@ int kvm_set_ipa_limit(void);
#define __KVM_HAVE_ARCH_VM_ALLOC
struct kvm *kvm_arch_alloc_vm(void);
-int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type);
-
static inline bool kvm_vm_is_protected(struct kvm *kvm)
{
return false;
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 74735a864eee..eaac8dec97de 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -162,7 +162,7 @@ int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size,
void free_hyp_pgds(void);
void stage2_unmap_vm(struct kvm *kvm);
-int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu);
+int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long type);
void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu);
int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
phys_addr_t pa, unsigned long size, bool writable);
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 6a32eaf768e5..694ba3792e9d 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -135,28 +135,24 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
int ret;
- ret = kvm_arm_setup_stage2(kvm, type);
- if (ret)
- return ret;
-
- ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu);
- if (ret)
- return ret;
-
ret = kvm_share_hyp(kvm, kvm + 1);
if (ret)
- goto out_free_stage2_pgd;
+ return ret;
ret = kvm_init_pvm(kvm);
if (ret)
- goto out_free_stage2_pgd;
+ goto err_unshare_kvm;
if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL)) {
ret = -ENOMEM;
- goto out_free_stage2_pgd;
+ goto err_unshare_kvm;
}
cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
+ ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
+ if (ret)
+ goto err_free_cpumask;
+
kvm_vgic_early_init(kvm);
/* The maximum number of VCPUs is limited by the host's GIC model */
@@ -164,9 +160,12 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
set_default_spectre(kvm);
- return ret;
-out_free_stage2_pgd:
- kvm_free_stage2_pgd(&kvm->arch.mmu);
+ return 0;
+
+err_free_cpumask:
+ free_cpumask_var(kvm->arch.supported_cpus);
+err_unshare_kvm:
+ kvm_unshare_hyp(kvm, kvm + 1);
return ret;
}
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index e77686d54e9f..0071f035dde8 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -618,15 +618,40 @@ static struct kvm_pgtable_mm_ops kvm_s2_mm_ops = {
* kvm_init_stage2_mmu - Initialise a S2 MMU structure
* @kvm: The pointer to the KVM structure
* @mmu: The pointer to the s2 MMU structure
+ * @type: The machine type of the virtual machine
*
* Allocates only the stage-2 HW PGD level table(s).
* Note we don't need locking here as this is only called when the VM is
* created, which can only be done once.
*/
-int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu)
+int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu, unsigned long type)
{
+ u32 kvm_ipa_limit = get_kvm_ipa_limit();
int cpu, err;
struct kvm_pgtable *pgt;
+ u64 mmfr0, mmfr1;
+ u32 phys_shift;
+
+ if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
+ return -EINVAL;
+
+ phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type);
+ if (phys_shift) {
+ if (phys_shift > kvm_ipa_limit ||
+ phys_shift < ARM64_MIN_PARANGE_BITS)
+ return -EINVAL;
+ } else {
+ phys_shift = KVM_PHYS_SHIFT;
+ if (phys_shift > kvm_ipa_limit) {
+ pr_warn_once("%s using unsupported default IPA limit, upgrade your VMM\n",
+ current->comm);
+ return -EINVAL;
+ }
+ }
+
+ mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+ mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
+ kvm->arch.vtcr = kvm_get_vtcr(mmfr0, mmfr1, phys_shift);
if (mmu->pgt != NULL) {
kvm_err("kvm_arch already initialized?\n");
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index ecc40c8cd6f6..c07265ea72fd 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -370,32 +370,3 @@ int kvm_set_ipa_limit(void)
return 0;
}
-
-int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type)
-{
- u64 mmfr0, mmfr1;
- u32 phys_shift;
-
- if (type & ~KVM_VM_TYPE_ARM_IPA_SIZE_MASK)
- return -EINVAL;
-
- phys_shift = KVM_VM_TYPE_ARM_IPA_SIZE(type);
- if (phys_shift) {
- if (phys_shift > kvm_ipa_limit ||
- phys_shift < ARM64_MIN_PARANGE_BITS)
- return -EINVAL;
- } else {
- phys_shift = KVM_PHYS_SHIFT;
- if (phys_shift > kvm_ipa_limit) {
- pr_warn_once("%s using unsupported default IPA limit, upgrade your VMM\n",
- current->comm);
- return -EINVAL;
- }
- }
-
- mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
- mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
- kvm->arch.vtcr = kvm_get_vtcr(mmfr0, mmfr1, phys_shift);
-
- return 0;
-}
--
2.36.1.124.g0e6072fb45-goog
More information about the linux-arm-kernel
mailing list