Add support for H_REG_SNS hcall so that asynchronous page fault mechanism can be supported on PowerKVM guests.
This hcall essentially issues KVM_PPC_SET_SNS to let the host map and pin the memory containing the Subvention Notification Structure. It also claims SPAPR_IRQ_SNS to be used as subvention notification interrupt. Note: Updates to linux-headers/linux/kvm.h are temporary pending headers update. Signed-off-by: Bharata B Rao <bhar...@linux.ibm.com> --- hw/ppc/spapr.c | 3 ++ hw/ppc/spapr_hcall.c | 56 +++++++++++++++++++++++++++++++++ include/hw/ppc/spapr.h | 3 ++ include/hw/ppc/spapr_irq.h | 1 + linux-headers/asm-powerpc/kvm.h | 6 ++++ linux-headers/linux/kvm.h | 1 + target/ppc/kvm.c | 14 +++++++++ target/ppc/kvm_ppc.h | 10 ++++++ 8 files changed, 94 insertions(+) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 81699d4f8b..5f1f75826d 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -2830,6 +2830,9 @@ static void spapr_machine_init(MachineState *machine) /* Enable H_PAGE_INIT */ kvmppc_enable_h_page_init(); + + /* Enable H_REG_SNS */ + kvmppc_enable_h_reg_sns(); } /* map RAM */ diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c index 0e9a5b2e40..957edecb13 100644 --- a/hw/ppc/spapr_hcall.c +++ b/hw/ppc/spapr_hcall.c @@ -1405,6 +1405,59 @@ static target_ulong h_update_dt(PowerPCCPU *cpu, SpaprMachineState *spapr, return H_SUCCESS; } +static target_ulong deregister_sns(PowerPCCPU *cpu, SpaprMachineState *spapr) +{ + spapr->sns_addr = -1; + spapr->sns_len = 0; + spapr_irq_free(spapr, SPAPR_IRQ_SNS, 1); + + return H_SUCCESS; +} + +static target_ulong h_reg_sns(PowerPCCPU *cpu, SpaprMachineState *spapr, + target_ulong opcode, target_ulong *args) +{ + target_ulong addr = args[0]; + target_ulong len = args[1]; + + if (addr == -1) { + return deregister_sns(cpu, spapr); + } + + /* + * If SNS area is already registered, can't register again before + * deregistering it first. + */ + if (spapr->sns_addr == -1) { + return H_PARAMETER; + } + + if (!QEMU_IS_ALIGNED(addr, 4096)) { + return H_PARAMETER; + } + + if (len < 256) { + return H_P2; + } + + /* TODO: SNS area is not allowed to cross a page boundary */ + + /* KVM_PPC_SET_SNS ioctl */ + if (kvmppc_set_sns_reg(addr, len)) { + return H_PARAMETER; + } + + /* Record SNS addr and len */ + spapr->sns_addr = addr; + spapr->sns_len = len; + + /* Register irq source for sending ESN notification */ + spapr_irq_claim(spapr, SPAPR_IRQ_SNS, false, &error_fatal); + args[1] = SPAPR_IRQ_SNS; /* irq no in R5 */ + + return H_SUCCESS; +} + static spapr_hcall_fn papr_hypercall_table[(MAX_HCALL_OPCODE / 4) + 1]; static spapr_hcall_fn kvmppc_hypercall_table[KVMPPC_HCALL_MAX - KVMPPC_HCALL_BASE + 1]; static spapr_hcall_fn svm_hypercall_table[(SVM_HCALL_MAX - SVM_HCALL_BASE) / 4 + 1]; @@ -1545,6 +1598,9 @@ static void hypercall_register_types(void) spapr_register_hypercall(KVMPPC_H_CAS, h_client_architecture_support); spapr_register_hypercall(KVMPPC_H_UPDATE_DT, h_update_dt); + + /* SNS memory area registration */ + spapr_register_hypercall(H_REG_SNS, h_reg_sns); } type_init(hypercall_register_types) diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index 637652ad16..934f9e066e 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -252,6 +252,8 @@ struct SpaprMachineState { uint32_t numa_assoc_array[MAX_NODES + NVGPU_MAX_NUM][NUMA_ASSOC_SIZE]; Error *fwnmi_migration_blocker; + uint64_t sns_addr; + uint64_t sns_len; }; #define H_SUCCESS 0 @@ -549,6 +551,7 @@ struct SpaprMachineState { #define H_SCM_UNBIND_MEM 0x3F0 #define H_SCM_UNBIND_ALL 0x3FC #define H_SCM_HEALTH 0x400 +#define H_REG_SNS 0x41C #define H_RPT_INVALIDATE 0x448 #define MAX_HCALL_OPCODE H_RPT_INVALIDATE diff --git a/include/hw/ppc/spapr_irq.h b/include/hw/ppc/spapr_irq.h index c22a72c9e2..26c680f065 100644 --- a/include/hw/ppc/spapr_irq.h +++ b/include/hw/ppc/spapr_irq.h @@ -21,6 +21,7 @@ #define SPAPR_XIRQ_BASE XICS_IRQ_BASE /* 0x1000 */ #define SPAPR_IRQ_EPOW (SPAPR_XIRQ_BASE + 0x0000) #define SPAPR_IRQ_HOTPLUG (SPAPR_XIRQ_BASE + 0x0001) +#define SPAPR_IRQ_SNS (SPAPR_XIRQ_BASE + 0x0002) #define SPAPR_IRQ_VIO (SPAPR_XIRQ_BASE + 0x0100) /* 256 VIO devices */ #define SPAPR_IRQ_PCI_LSI (SPAPR_XIRQ_BASE + 0x0200) /* 32+ PHBs devices */ diff --git a/linux-headers/asm-powerpc/kvm.h b/linux-headers/asm-powerpc/kvm.h index 9f18fa090f..d72739126a 100644 --- a/linux-headers/asm-powerpc/kvm.h +++ b/linux-headers/asm-powerpc/kvm.h @@ -470,6 +470,12 @@ struct kvm_ppc_cpu_char { #define KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR (1ULL << 61) #define KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE (1ull << 58) +/* For KVM_PPC_SET_SNS */ +struct kvm_ppc_sns_reg { + __u64 addr; + __u64 len; +}; + /* Per-vcpu XICS interrupt controller state */ #define KVM_REG_PPC_ICP_STATE (KVM_REG_PPC | KVM_REG_SIZE_U64 | 0x8c) diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h index bcaf66cc4d..a76945fcbc 100644 --- a/linux-headers/linux/kvm.h +++ b/linux-headers/linux/kvm.h @@ -1458,6 +1458,7 @@ struct kvm_s390_ucas_mapping { #define KVM_SET_PMU_EVENT_FILTER _IOW(KVMIO, 0xb2, struct kvm_pmu_event_filter) #define KVM_PPC_SVM_OFF _IO(KVMIO, 0xb3) #define KVM_ARM_MTE_COPY_TAGS _IOR(KVMIO, 0xb4, struct kvm_arm_copy_mte_tags) +#define KVM_PPC_SET_SNS _IOR(KVMIO, 0xb5, struct kvm_ppc_sns_reg) /* ioctl for vm fd */ #define KVM_CREATE_DEVICE _IOWR(KVMIO, 0xe0, struct kvm_create_device) diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c index dc93b99189..330985c8a0 100644 --- a/target/ppc/kvm.c +++ b/target/ppc/kvm.c @@ -2047,6 +2047,11 @@ void kvmppc_enable_h_rpt_invalidate(void) kvmppc_enable_hcall(kvm_state, H_RPT_INVALIDATE); } +void kvmppc_enable_h_reg_sns(void) +{ + kvmppc_enable_hcall(kvm_state, H_REG_SNS); +} + void kvmppc_set_papr(PowerPCCPU *cpu) { CPUState *cs = CPU(cpu); @@ -2959,3 +2964,12 @@ bool kvm_arch_cpu_check_are_resettable(void) { return true; } + +int kvmppc_set_sns_reg(target_ulong addr, target_ulong len) +{ + struct kvm_ppc_sns_reg sns_reg; + + sns_reg.addr = addr; + sns_reg.len = len; + return kvm_vm_ioctl(kvm_state, KVM_PPC_SET_SNS, &sns_reg); +} diff --git a/target/ppc/kvm_ppc.h b/target/ppc/kvm_ppc.h index ee9325bf9a..c22bc3253e 100644 --- a/target/ppc/kvm_ppc.h +++ b/target/ppc/kvm_ppc.h @@ -25,6 +25,7 @@ void kvmppc_enable_set_mode_hcall(void); void kvmppc_enable_clear_ref_mod_hcalls(void); void kvmppc_enable_h_page_init(void); void kvmppc_enable_h_rpt_invalidate(void); +void kvmppc_enable_h_reg_sns(void); void kvmppc_set_papr(PowerPCCPU *cpu); int kvmppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr); void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int mpic_proxy); @@ -87,6 +88,7 @@ void kvmppc_set_reg_ppc_online(PowerPCCPU *cpu, unsigned int online); void kvmppc_set_reg_tb_offset(PowerPCCPU *cpu, int64_t tb_offset); int kvm_handle_nmi(PowerPCCPU *cpu, struct kvm_run *run); +int kvmppc_set_sns_reg(target_ulong addr, target_ulong len); #else @@ -157,6 +159,10 @@ static inline void kvmppc_enable_h_rpt_invalidate(void) g_assert_not_reached(); } +static inline void kvmppc_enable_h_reg_sns(void) +{ +} + static inline void kvmppc_set_papr(PowerPCCPU *cpu) { } @@ -430,6 +436,10 @@ static inline bool kvmppc_pvr_workaround_required(PowerPCCPU *cpu) return false; } +int kvmppc_set_sns_reg(target_ulong addr, target_ulong len) +{ + return -ENOSYS; +} #endif #ifndef CONFIG_KVM -- 2.31.1