From 20475f784d29991b3b843c80c38a36f2ebb35ac4 Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Mon, 16 Nov 2015 11:28:18 +0000 Subject: [PATCH] arm64: KVM: Add support for 16-bit VMID The ARMv8.1 architecture extension allows to choose between 8-bit and 16-bit of VMID, so use this capability for KVM. Reviewed-by: Christoffer Dall Signed-off-by: Vladimir Murzin Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_arm.h | 2 +- arch/arm/include/asm/kvm_mmu.h | 5 +++++ arch/arm/kvm/arm.c | 10 ++++++++-- arch/arm64/include/asm/kvm_arm.h | 3 ++- arch/arm64/include/asm/kvm_mmu.h | 8 ++++++++ arch/arm64/kvm/hyp-init.S | 9 +++++++++ 6 files changed, 33 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index 01d4d7abe34e..e22089fb44dc 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -164,7 +164,7 @@ #define VTTBR_BADDR_SHIFT (VTTBR_X - 1) #define VTTBR_BADDR_MASK (((_AC(1, ULL) << (40 - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) #define VTTBR_VMID_SHIFT _AC(48, ULL) -#define VTTBR_VMID_MASK (_AC(0xff, ULL) << VTTBR_VMID_SHIFT) +#define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT) /* Hyp Syndrome Register (HSR) bits */ #define HSR_EC_SHIFT (26) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 405aa1883307..9203c21b4673 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -279,6 +279,11 @@ static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd, pgd_t *merged_hyp_pgd, unsigned long hyp_idmap_start) { } +static inline unsigned int kvm_get_vmid_bits(void) +{ + return 8; +} + #endif /* !__ASSEMBLY__ */ #endif /* __ARM_KVM_MMU_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 6e35d1d7893e..f6bcc2e4a133 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -59,7 +59,8 @@ static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu); /* The VMID used in the VTTBR */ static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); -static u8 kvm_next_vmid; +static u32 kvm_next_vmid; +static unsigned int kvm_vmid_bits __read_mostly; static DEFINE_SPINLOCK(kvm_vmid_lock); static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu) @@ -434,11 +435,12 @@ static void update_vttbr(struct kvm *kvm) kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen); kvm->arch.vmid = kvm_next_vmid; kvm_next_vmid++; + kvm_next_vmid &= (1 << kvm_vmid_bits) - 1; /* update vttbr to be used with the new vmid */ pgd_phys = virt_to_phys(kvm_get_hwpgd(kvm)); BUG_ON(pgd_phys & ~VTTBR_BADDR_MASK); - vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK; + vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK(kvm_vmid_bits); kvm->arch.vttbr = pgd_phys | vmid; spin_unlock(&kvm_vmid_lock); @@ -1135,6 +1137,10 @@ static int init_hyp_mode(void) kvm_perf_init(); + /* set size of VMID supported by CPU */ + kvm_vmid_bits = kvm_get_vmid_bits(); + kvm_info("%d-bit VMID\n", kvm_vmid_bits); + kvm_info("Hyp mode initialized successfully\n"); return 0; diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 5e6857b6bdc4..738a95f93e49 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -125,6 +125,7 @@ #define VTCR_EL2_SL0_LVL1 (1 << 6) #define VTCR_EL2_T0SZ_MASK 0x3f #define VTCR_EL2_T0SZ_40B 24 +#define VTCR_EL2_VS 19 /* * We configure the Stage-2 page tables to always restrict the IPA space to be @@ -169,7 +170,7 @@ #define VTTBR_BADDR_SHIFT (VTTBR_X - 1) #define VTTBR_BADDR_MASK (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_BADDR_SHIFT) #define VTTBR_VMID_SHIFT (UL(48)) -#define VTTBR_VMID_MASK (UL(0xFF) << VTTBR_VMID_SHIFT) +#define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT) /* Hyp System Trap Register */ #define HSTR_EL2_T(x) (1 << x) diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 54cba803e2d9..0bf8b4320a91 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -20,6 +20,7 @@ #include #include +#include /* * As we only have the TTBR0_EL2 register, we cannot express @@ -301,5 +302,12 @@ static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd, merged_hyp_pgd[idmap_idx] = __pgd(__pa(boot_hyp_pgd) | PMD_TYPE_TABLE); } +static inline unsigned int kvm_get_vmid_bits(void) +{ + int reg = read_system_reg(SYS_ID_AA64MMFR1_EL1); + + return (cpuid_feature_extract_field(reg, ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8; +} + #endif /* __ASSEMBLY__ */ #endif /* __ARM64_KVM_MMU_H__ */ diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S index 178ba2248a98..3e568dcd907b 100644 --- a/arch/arm64/kvm/hyp-init.S +++ b/arch/arm64/kvm/hyp-init.S @@ -94,6 +94,15 @@ __do_hyp_init: */ mrs x5, ID_AA64MMFR0_EL1 bfi x4, x5, #16, #3 + /* + * Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS bit in + * VTCR_EL2. + */ + mrs x5, ID_AA64MMFR1_EL1 + ubfx x5, x5, #5, #1 + lsl x5, x5, #VTCR_EL2_VS + orr x4, x4, x5 + msr vtcr_el2, x4 mrs x4, mair_el1 -- GitLab