Merge branch kvm-arm64/nv-6.8-prefix into kvmarm-master/next

* kvm-arm64/nv-6.8-prefix:
  : .
  : Nested Virtualization support update, focussing on the
  : NV2 support (VNCR mapping and such).
  : .
  KVM: arm64: nv: Handle virtual EL2 registers in vcpu_read/write_sys_reg()
  KVM: arm64: nv: Map VNCR-capable registers to a separate page
  KVM: arm64: nv: Add EL2_REG_VNCR()/EL2_REG_REDIR() sysreg helpers
  KVM: arm64: Introduce a bad_trap() primitive for unexpected trap handling
  KVM: arm64: nv: Add include containing the VNCR_EL2 offsets
  KVM: arm64: nv: Add non-VHE-EL2->EL1 translation helpers
  KVM: arm64: nv: Drop EL12 register traps that are redirected to VNCR
  KVM: arm64: nv: Compute NV view of idregs as a one-off
  KVM: arm64: nv: Hoist vcpu_has_nv() into is_hyp_ctxt()
  arm64: cpufeatures: Restrict NV support to FEAT_NV2

Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: Marc Zyngier

arch/arm64/include/asm/kvm_emulate.h

@@ -17,6 +17,7 @@
 #include <asm/esr.h>
 #include <asm/kvm_arm.h>
 #include <asm/kvm_hyp.h>
+#include <asm/kvm_nested.h>
 #include <asm/ptrace.h>
 #include <asm/cputype.h>
 #include <asm/virt.h>
@@ -54,11 +55,6 @@ void kvm_emulate_nested_eret(struct kvm_vcpu *vcpu);
 int kvm_inject_nested_sync(struct kvm_vcpu *vcpu, u64 esr_el2);
 int kvm_inject_nested_irq(struct kvm_vcpu *vcpu);
 
-static inline bool vcpu_has_feature(const struct kvm_vcpu *vcpu, int feature)
-{
-	return test_bit(feature, vcpu->kvm->arch.vcpu_features);
-}
-
 #if defined(__KVM_VHE_HYPERVISOR__) || defined(__KVM_NVHE_HYPERVISOR__)
 static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
 {
@@ -248,7 +244,7 @@ static inline bool __is_hyp_ctxt(const struct kvm_cpu_context *ctxt)
 
 static inline bool is_hyp_ctxt(const struct kvm_vcpu *vcpu)
 {
-	return __is_hyp_ctxt(&vcpu->arch.ctxt);
+	return vcpu_has_nv(vcpu) && __is_hyp_ctxt(&vcpu->arch.ctxt);
 }
 
 /*

arch/arm64/include/asm/kvm_host.h

@@ -27,6 +27,7 @@
 #include <asm/fpsimd.h>
 #include <asm/kvm.h>
 #include <asm/kvm_asm.h>
+#include <asm/vncr_mapping.h>
 
 #define __KVM_HAVE_ARCH_INTC_INITIALIZED
 
@@ -306,6 +307,7 @@ struct kvm_arch {
 	 * Atomic access to multiple idregs are guarded by kvm_arch.config_lock.
 	 */
 #define IDREG_IDX(id)		(((sys_reg_CRm(id) - 1) << 3) | sys_reg_Op2(id))
+#define IDX_IDREG(idx)		sys_reg(3, 0, 0, ((idx) >> 3) + 1, (idx) & Op2_mask)
 #define IDREG(kvm, id)		((kvm)->arch.id_regs[IDREG_IDX(id)])
 #define KVM_ARM_ID_REG_NUM	(IDREG_IDX(sys_reg(3, 0, 0, 7, 7)) + 1)
 	u64 id_regs[KVM_ARM_ID_REG_NUM];
@@ -324,33 +326,33 @@ struct kvm_vcpu_fault_info {
 	u64 disr_el1;		/* Deferred [SError] Status Register */
 };
 
+/*
+ * VNCR() just places the VNCR_capable registers in the enum after
+ * __VNCR_START__, and the value (after correction) to be an 8-byte offset
+ * from the VNCR base. As we don't require the enum to be otherwise ordered,
+ * we need the terrible hack below to ensure that we correctly size the
+ * sys_regs array, no matter what.
+ *
+ * The __MAX__ macro has been lifted from Sean Eron Anderson's wonderful
+ * treasure trove of bit hacks:
+ * https://graphics.stanford.edu/~seander/bithacks.html#IntegerMinOrMax
+ */
+#define __MAX__(x,y)	((x) ^ (((x) ^ (y)) & -((x) < (y))))
+#define VNCR(r)						\
+	__before_##r,					\
+	r = __VNCR_START__ + ((VNCR_ ## r) / 8),	\
+	__after_##r = __MAX__(__before_##r - 1, r)
+
 enum vcpu_sysreg {
 	__INVALID_SYSREG__,   /* 0 is reserved as an invalid value */
 	MPIDR_EL1,	/* MultiProcessor Affinity Register */
 	CLIDR_EL1,	/* Cache Level ID Register */
 	CSSELR_EL1,	/* Cache Size Selection Register */
-	SCTLR_EL1,	/* System Control Register */
-	ACTLR_EL1,	/* Auxiliary Control Register */
-	CPACR_EL1,	/* Coprocessor Access Control */
-	ZCR_EL1,	/* SVE Control */
-	TTBR0_EL1,	/* Translation Table Base Register 0 */
-	TTBR1_EL1,	/* Translation Table Base Register 1 */
-	TCR_EL1,	/* Translation Control Register */
-	TCR2_EL1,	/* Extended Translation Control Register */
-	ESR_EL1,	/* Exception Syndrome Register */
-	AFSR0_EL1,	/* Auxiliary Fault Status Register 0 */
-	AFSR1_EL1,	/* Auxiliary Fault Status Register 1 */
-	FAR_EL1,	/* Fault Address Register */
-	MAIR_EL1,	/* Memory Attribute Indirection Register */
-	VBAR_EL1,	/* Vector Base Address Register */
-	CONTEXTIDR_EL1,	/* Context ID Register */
 	TPIDR_EL0,	/* Thread ID, User R/W */
 	TPIDRRO_EL0,	/* Thread ID, User R/O */
 	TPIDR_EL1,	/* Thread ID, Privileged */
-	AMAIR_EL1,	/* Aux Memory Attribute Indirection Register */
 	CNTKCTL_EL1,	/* Timer Control Register (EL1) */
 	PAR_EL1,	/* Physical Address Register */
-	MDSCR_EL1,	/* Monitor Debug System Control Register */
 	MDCCINT_EL1,	/* Monitor Debug Comms Channel Interrupt Enable Reg */
 	OSLSR_EL1,	/* OS Lock Status Register */
 	DISR_EL1,	/* Deferred Interrupt Status Register */
@@ -381,48 +383,26 @@ enum vcpu_sysreg {
 	APGAKEYLO_EL1,
 	APGAKEYHI_EL1,
 
-	ELR_EL1,
-	SP_EL1,
-	SPSR_EL1,
-
-	CNTVOFF_EL2,
-	CNTV_CVAL_EL0,
-	CNTV_CTL_EL0,
-	CNTP_CVAL_EL0,
-	CNTP_CTL_EL0,
-
 	/* Memory Tagging Extension registers */
 	RGSR_EL1,	/* Random Allocation Tag Seed Register */
 	GCR_EL1,	/* Tag Control Register */
-	TFSR_EL1,	/* Tag Fault Status Register (EL1) */
 	TFSRE0_EL1,	/* Tag Fault Status Register (EL0) */
 
-	/* Permission Indirection Extension registers */
-	PIR_EL1,       /* Permission Indirection Register 1 (EL1) */
-	PIRE0_EL1,     /*  Permission Indirection Register 0 (EL1) */
-
 	/* 32bit specific registers. */
 	DACR32_EL2,	/* Domain Access Control Register */
 	IFSR32_EL2,	/* Instruction Fault Status Register */
 	FPEXC32_EL2,	/* Floating-Point Exception Control Register */
 	DBGVCR32_EL2,	/* Debug Vector Catch Register */
 
 	/* EL2 registers */
-	VPIDR_EL2,	/* Virtualization Processor ID Register */
-	VMPIDR_EL2,	/* Virtualization Multiprocessor ID Register */
 	SCTLR_EL2,	/* System Control Register (EL2) */
 	ACTLR_EL2,	/* Auxiliary Control Register (EL2) */
-	HCR_EL2,	/* Hypervisor Configuration Register */
 	MDCR_EL2,	/* Monitor Debug Configuration Register (EL2) */
 	CPTR_EL2,	/* Architectural Feature Trap Register (EL2) */
-	HSTR_EL2,	/* Hypervisor System Trap Register */
 	HACR_EL2,	/* Hypervisor Auxiliary Control Register */
-	HCRX_EL2,	/* Extended Hypervisor Configuration Register */
 	TTBR0_EL2,	/* Translation Table Base Register 0 (EL2) */
 	TTBR1_EL2,	/* Translation Table Base Register 1 (EL2) */
 	TCR_EL2,	/* Translation Control Register (EL2) */
-	VTTBR_EL2,	/* Virtualization Translation Table Base Register */
-	VTCR_EL2,	/* Virtualization Translation Control Register */
 	SPSR_EL2,	/* EL2 saved program status register */
 	ELR_EL2,	/* EL2 exception link register */
 	AFSR0_EL2,	/* Auxiliary Fault Status Register 0 (EL2) */
@@ -435,20 +415,62 @@ enum vcpu_sysreg {
 	VBAR_EL2,	/* Vector Base Address Register (EL2) */
 	RVBAR_EL2,	/* Reset Vector Base Address Register */
 	CONTEXTIDR_EL2,	/* Context ID Register (EL2) */
-	TPIDR_EL2,	/* EL2 Software Thread ID Register */
 	CNTHCTL_EL2,	/* Counter-timer Hypervisor Control register */
 	SP_EL2,		/* EL2 Stack Pointer */
-	HFGRTR_EL2,
-	HFGWTR_EL2,
-	HFGITR_EL2,
-	HDFGRTR_EL2,
-	HDFGWTR_EL2,
-	HAFGRTR_EL2,
 	CNTHP_CTL_EL2,
 	CNTHP_CVAL_EL2,
 	CNTHV_CTL_EL2,
 	CNTHV_CVAL_EL2,
 
+	__VNCR_START__,	/* Any VNCR-capable reg goes after this point */
+
+	VNCR(SCTLR_EL1),/* System Control Register */
+	VNCR(ACTLR_EL1),/* Auxiliary Control Register */
+	VNCR(CPACR_EL1),/* Coprocessor Access Control */
+	VNCR(ZCR_EL1),	/* SVE Control */
+	VNCR(TTBR0_EL1),/* Translation Table Base Register 0 */
+	VNCR(TTBR1_EL1),/* Translation Table Base Register 1 */
+	VNCR(TCR_EL1),	/* Translation Control Register */
+	VNCR(TCR2_EL1),	/* Extended Translation Control Register */
+	VNCR(ESR_EL1),	/* Exception Syndrome Register */
+	VNCR(AFSR0_EL1),/* Auxiliary Fault Status Register 0 */
+	VNCR(AFSR1_EL1),/* Auxiliary Fault Status Register 1 */
+	VNCR(FAR_EL1),	/* Fault Address Register */
+	VNCR(MAIR_EL1),	/* Memory Attribute Indirection Register */
+	VNCR(VBAR_EL1),	/* Vector Base Address Register */
+	VNCR(CONTEXTIDR_EL1),	/* Context ID Register */
+	VNCR(AMAIR_EL1),/* Aux Memory Attribute Indirection Register */
+	VNCR(MDSCR_EL1),/* Monitor Debug System Control Register */
+	VNCR(ELR_EL1),
+	VNCR(SP_EL1),
+	VNCR(SPSR_EL1),
+	VNCR(TFSR_EL1),	/* Tag Fault Status Register (EL1) */
+	VNCR(VPIDR_EL2),/* Virtualization Processor ID Register */
+	VNCR(VMPIDR_EL2),/* Virtualization Multiprocessor ID Register */
+	VNCR(HCR_EL2),	/* Hypervisor Configuration Register */
+	VNCR(HSTR_EL2),	/* Hypervisor System Trap Register */
+	VNCR(VTTBR_EL2),/* Virtualization Translation Table Base Register */
+	VNCR(VTCR_EL2),	/* Virtualization Translation Control Register */
+	VNCR(TPIDR_EL2),/* EL2 Software Thread ID Register */
+	VNCR(HCRX_EL2),	/* Extended Hypervisor Configuration Register */
+
+	/* Permission Indirection Extension registers */
+	VNCR(PIR_EL1),	 /* Permission Indirection Register 1 (EL1) */
+	VNCR(PIRE0_EL1), /*  Permission Indirection Register 0 (EL1) */
+
+	VNCR(HFGRTR_EL2),
+	VNCR(HFGWTR_EL2),
+	VNCR(HFGITR_EL2),
+	VNCR(HDFGRTR_EL2),
+	VNCR(HDFGWTR_EL2),
+	VNCR(HAFGRTR_EL2),
+
+	VNCR(CNTVOFF_EL2),
+	VNCR(CNTV_CVAL_EL0),
+	VNCR(CNTV_CTL_EL0),
+	VNCR(CNTP_CVAL_EL0),
+	VNCR(CNTP_CTL_EL0),
+
 	NR_SYS_REGS	/* Nothing after this line! */
 };
 
@@ -465,6 +487,9 @@ struct kvm_cpu_context {
 	u64 sys_regs[NR_SYS_REGS];
 
 	struct kvm_vcpu *__hyp_running_vcpu;
+
+	/* This pointer has to be 4kB aligned. */
+	u64 *vncr_array;
 };
 
 struct kvm_host_data {
@@ -827,8 +852,19 @@ struct kvm_vcpu_arch {
  * accessed by a running VCPU.  For example, for userspace access or
  * for system registers that are never context switched, but only
  * emulated.
+ *
+ * Don't bother with VNCR-based accesses in the nVHE code, it has no
+ * business dealing with NV.
  */
-#define __ctxt_sys_reg(c,r)	(&(c)->sys_regs[(r)])
+static inline u64 *__ctxt_sys_reg(const struct kvm_cpu_context *ctxt, int r)
+{
+#if !defined (__KVM_NVHE_HYPERVISOR__)
+	if (unlikely(cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) &&
+		     r >= __VNCR_START__ && ctxt->vncr_array))
+		return &ctxt->vncr_array[r - __VNCR_START__];
+#endif
+	return (u64 *)&ctxt->sys_regs[r];
+}
 
 #define ctxt_sys_reg(c,r)	(*__ctxt_sys_reg(c,r))
 
@@ -872,6 +908,7 @@ static inline bool __vcpu_read_sys_reg_from_cpu(int reg, u64 *val)
 	case AMAIR_EL1:		*val = read_sysreg_s(SYS_AMAIR_EL12);	break;
 	case CNTKCTL_EL1:	*val = read_sysreg_s(SYS_CNTKCTL_EL12);	break;
 	case ELR_EL1:		*val = read_sysreg_s(SYS_ELR_EL12);	break;
+	case SPSR_EL1:		*val = read_sysreg_s(SYS_SPSR_EL12);	break;
 	case PAR_EL1:		*val = read_sysreg_par();		break;
 	case DACR32_EL2:	*val = read_sysreg_s(SYS_DACR32_EL2);	break;
 	case IFSR32_EL2:	*val = read_sysreg_s(SYS_IFSR32_EL2);	break;
@@ -916,6 +953,7 @@ static inline bool __vcpu_write_sys_reg_to_cpu(u64 val, int reg)
 	case AMAIR_EL1:		write_sysreg_s(val, SYS_AMAIR_EL12);	break;
 	case CNTKCTL_EL1:	write_sysreg_s(val, SYS_CNTKCTL_EL12);	break;
 	case ELR_EL1:		write_sysreg_s(val, SYS_ELR_EL12);	break;
+	case SPSR_EL1:		write_sysreg_s(val, SYS_SPSR_EL12);	break;
 	case PAR_EL1:		write_sysreg_s(val, SYS_PAR_EL1);	break;
 	case DACR32_EL2:	write_sysreg_s(val, SYS_DACR32_EL2);	break;
 	case IFSR32_EL2:	write_sysreg_s(val, SYS_IFSR32_EL2);	break;
@@ -1178,6 +1216,13 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu);
 #define kvm_vm_has_ran_once(kvm)					\
 	(test_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &(kvm)->arch.flags))
 
+static inline bool __vcpu_has_feature(const struct kvm_arch *ka, int feature)
+{
+	return test_bit(feature, ka->vcpu_features);
+}
+
+#define vcpu_has_feature(v, f)	__vcpu_has_feature(&(v)->kvm->arch, (f))
+
 int kvm_trng_call(struct kvm_vcpu *vcpu);
 #ifdef CONFIG_KVM
 extern phys_addr_t hyp_mem_base;

arch/arm64/include/asm/kvm_nested.h

@@ -2,8 +2,9 @@
 #ifndef __ARM64_KVM_NESTED_H
 #define __ARM64_KVM_NESTED_H
 
-#include <asm/kvm_emulate.h>
+#include <linux/bitfield.h>
 #include <linux/kvm_host.h>
+#include <asm/kvm_emulate.h>
 
 static inline bool vcpu_has_nv(const struct kvm_vcpu *vcpu)
 {
@@ -12,12 +13,55 @@ static inline bool vcpu_has_nv(const struct kvm_vcpu *vcpu)
 		vcpu_has_feature(vcpu, KVM_ARM_VCPU_HAS_EL2));
 }
 
-extern bool __check_nv_sr_forward(struct kvm_vcpu *vcpu);
+/* Translation helpers from non-VHE EL2 to EL1 */
+static inline u64 tcr_el2_ps_to_tcr_el1_ips(u64 tcr_el2)
+{
+	return (u64)FIELD_GET(TCR_EL2_PS_MASK, tcr_el2) << TCR_IPS_SHIFT;
+}
+
+static inline u64 translate_tcr_el2_to_tcr_el1(u64 tcr)
+{
+	return TCR_EPD1_MASK |				/* disable TTBR1_EL1 */
+	       ((tcr & TCR_EL2_TBI) ? TCR_TBI0 : 0) |
+	       tcr_el2_ps_to_tcr_el1_ips(tcr) |
+	       (tcr & TCR_EL2_TG0_MASK) |
+	       (tcr & TCR_EL2_ORGN0_MASK) |
+	       (tcr & TCR_EL2_IRGN0_MASK) |
+	       (tcr & TCR_EL2_T0SZ_MASK);
+}
+
+static inline u64 translate_cptr_el2_to_cpacr_el1(u64 cptr_el2)
+{
+	u64 cpacr_el1 = 0;
+
+	if (cptr_el2 & CPTR_EL2_TTA)
+		cpacr_el1 |= CPACR_ELx_TTA;
+	if (!(cptr_el2 & CPTR_EL2_TFP))
+		cpacr_el1 |= CPACR_ELx_FPEN;
+	if (!(cptr_el2 & CPTR_EL2_TZ))
+		cpacr_el1 |= CPACR_ELx_ZEN;
 
-struct sys_reg_params;
-struct sys_reg_desc;
+	return cpacr_el1;
+}
+
+static inline u64 translate_sctlr_el2_to_sctlr_el1(u64 val)
+{
+	/* Only preserve the minimal set of bits we support */
+	val &= (SCTLR_ELx_M | SCTLR_ELx_A | SCTLR_ELx_C | SCTLR_ELx_SA |
+		SCTLR_ELx_I | SCTLR_ELx_IESB | SCTLR_ELx_WXN | SCTLR_ELx_EE);
+	val |= SCTLR_EL1_RES1;
+
+	return val;
+}
+
+static inline u64 translate_ttbr0_el2_to_ttbr0_el1(u64 ttbr0)
+{
+	/* Clear the ASID field */
+	return ttbr0 & ~GENMASK_ULL(63, 48);
+}
+
+extern bool __check_nv_sr_forward(struct kvm_vcpu *vcpu);
 
-void access_nested_id_reg(struct kvm_vcpu *v, struct sys_reg_params *p,
-			  const struct sys_reg_desc *r);
+int kvm_init_nv_sysregs(struct kvm *kvm);
 
 #endif /* __ARM64_KVM_NESTED_H */