diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_p9_entry.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_p9_entry.c | 930 |
1 files changed, 930 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_p9_entry.c b/arch/powerpc/kvm/book3s_hv_p9_entry.c new file mode 100644 index 000000000000..34bc0a8a1288 --- /dev/null +++ b/arch/powerpc/kvm/book3s_hv_p9_entry.c @@ -0,0 +1,930 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/kernel.h> +#include <linux/kvm_host.h> +#include <asm/asm-prototypes.h> +#include <asm/dbell.h> +#include <asm/ppc-opcode.h> + +#include "book3s_hv.h" + +static void load_spr_state(struct kvm_vcpu *vcpu, + struct p9_host_os_sprs *host_os_sprs) +{ + /* TAR is very fast */ + mtspr(SPRN_TAR, vcpu->arch.tar); + +#ifdef CONFIG_ALTIVEC + if (cpu_has_feature(CPU_FTR_ALTIVEC) && + current->thread.vrsave != vcpu->arch.vrsave) + mtspr(SPRN_VRSAVE, vcpu->arch.vrsave); +#endif + + if (vcpu->arch.hfscr & HFSCR_EBB) { + if (current->thread.ebbhr != vcpu->arch.ebbhr) + mtspr(SPRN_EBBHR, vcpu->arch.ebbhr); + if (current->thread.ebbrr != vcpu->arch.ebbrr) + mtspr(SPRN_EBBRR, vcpu->arch.ebbrr); + if (current->thread.bescr != vcpu->arch.bescr) + mtspr(SPRN_BESCR, vcpu->arch.bescr); + } + + if (cpu_has_feature(CPU_FTR_P9_TIDR) && + current->thread.tidr != vcpu->arch.tid) + mtspr(SPRN_TIDR, vcpu->arch.tid); + if (host_os_sprs->iamr != vcpu->arch.iamr) + mtspr(SPRN_IAMR, vcpu->arch.iamr); + if (host_os_sprs->amr != vcpu->arch.amr) + mtspr(SPRN_AMR, vcpu->arch.amr); + if (vcpu->arch.uamor != 0) + mtspr(SPRN_UAMOR, vcpu->arch.uamor); + if (current->thread.fscr != vcpu->arch.fscr) + mtspr(SPRN_FSCR, vcpu->arch.fscr); + if (current->thread.dscr != vcpu->arch.dscr) + mtspr(SPRN_DSCR, vcpu->arch.dscr); + if (vcpu->arch.pspb != 0) + mtspr(SPRN_PSPB, vcpu->arch.pspb); + + /* + * DAR, DSISR, and for nested HV, SPRGs must be set with MSR[RI] + * clear (or hstate set appropriately to catch those registers + * being clobbered if we take a MCE or SRESET), so those are done + * later. + */ + + if (!(vcpu->arch.ctrl & 1)) + mtspr(SPRN_CTRLT, 0); +} + +static void store_spr_state(struct kvm_vcpu *vcpu) +{ + vcpu->arch.tar = mfspr(SPRN_TAR); + +#ifdef CONFIG_ALTIVEC + if (cpu_has_feature(CPU_FTR_ALTIVEC)) + vcpu->arch.vrsave = mfspr(SPRN_VRSAVE); +#endif + + if (vcpu->arch.hfscr & HFSCR_EBB) { + vcpu->arch.ebbhr = mfspr(SPRN_EBBHR); + vcpu->arch.ebbrr = mfspr(SPRN_EBBRR); + vcpu->arch.bescr = mfspr(SPRN_BESCR); + } + + if (cpu_has_feature(CPU_FTR_P9_TIDR)) + vcpu->arch.tid = mfspr(SPRN_TIDR); + vcpu->arch.iamr = mfspr(SPRN_IAMR); + vcpu->arch.amr = mfspr(SPRN_AMR); + vcpu->arch.uamor = mfspr(SPRN_UAMOR); + vcpu->arch.fscr = mfspr(SPRN_FSCR); + vcpu->arch.dscr = mfspr(SPRN_DSCR); + vcpu->arch.pspb = mfspr(SPRN_PSPB); + + vcpu->arch.ctrl = mfspr(SPRN_CTRLF); +} + +/* Returns true if current MSR and/or guest MSR may have changed */ +bool load_vcpu_state(struct kvm_vcpu *vcpu, + struct p9_host_os_sprs *host_os_sprs) +{ + bool ret = false; + +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + if (cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) { + unsigned long guest_msr = vcpu->arch.shregs.msr; + if (MSR_TM_ACTIVE(guest_msr)) { + kvmppc_restore_tm_hv(vcpu, guest_msr, true); + ret = true; + } else if (vcpu->arch.hfscr & HFSCR_TM) { + mtspr(SPRN_TEXASR, vcpu->arch.texasr); + mtspr(SPRN_TFHAR, vcpu->arch.tfhar); + mtspr(SPRN_TFIAR, vcpu->arch.tfiar); + } + } +#endif + + load_spr_state(vcpu, host_os_sprs); + + load_fp_state(&vcpu->arch.fp); +#ifdef CONFIG_ALTIVEC + load_vr_state(&vcpu->arch.vr); +#endif + + return ret; +} +EXPORT_SYMBOL_GPL(load_vcpu_state); + +void store_vcpu_state(struct kvm_vcpu *vcpu) +{ + store_spr_state(vcpu); + + store_fp_state(&vcpu->arch.fp); +#ifdef CONFIG_ALTIVEC + store_vr_state(&vcpu->arch.vr); +#endif + +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + if (cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) { + unsigned long guest_msr = vcpu->arch.shregs.msr; + if (MSR_TM_ACTIVE(guest_msr)) { + kvmppc_save_tm_hv(vcpu, guest_msr, true); + } else if (vcpu->arch.hfscr & HFSCR_TM) { + vcpu->arch.texasr = mfspr(SPRN_TEXASR); + vcpu->arch.tfhar = mfspr(SPRN_TFHAR); + vcpu->arch.tfiar = mfspr(SPRN_TFIAR); + + if (!vcpu->arch.nested) { + vcpu->arch.load_tm++; /* see load_ebb comment */ + if (!vcpu->arch.load_tm) + vcpu->arch.hfscr &= ~HFSCR_TM; + } + } + } +#endif +} +EXPORT_SYMBOL_GPL(store_vcpu_state); + +void save_p9_host_os_sprs(struct p9_host_os_sprs *host_os_sprs) +{ + host_os_sprs->iamr = mfspr(SPRN_IAMR); + host_os_sprs->amr = mfspr(SPRN_AMR); +} +EXPORT_SYMBOL_GPL(save_p9_host_os_sprs); + +/* vcpu guest regs must already be saved */ +void restore_p9_host_os_sprs(struct kvm_vcpu *vcpu, + struct p9_host_os_sprs *host_os_sprs) +{ + /* + * current->thread.xxx registers must all be restored to host + * values before a potential context switch, otherwise the context + * switch itself will overwrite current->thread.xxx with the values + * from the guest SPRs. + */ + + mtspr(SPRN_SPRG_VDSO_WRITE, local_paca->sprg_vdso); + + if (cpu_has_feature(CPU_FTR_P9_TIDR) && + current->thread.tidr != vcpu->arch.tid) + mtspr(SPRN_TIDR, current->thread.tidr); + if (host_os_sprs->iamr != vcpu->arch.iamr) + mtspr(SPRN_IAMR, host_os_sprs->iamr); + if (vcpu->arch.uamor != 0) + mtspr(SPRN_UAMOR, 0); + if (host_os_sprs->amr != vcpu->arch.amr) + mtspr(SPRN_AMR, host_os_sprs->amr); + if (current->thread.fscr != vcpu->arch.fscr) + mtspr(SPRN_FSCR, current->thread.fscr); + if (current->thread.dscr != vcpu->arch.dscr) + mtspr(SPRN_DSCR, current->thread.dscr); + if (vcpu->arch.pspb != 0) + mtspr(SPRN_PSPB, 0); + + /* Save guest CTRL register, set runlatch to 1 */ + if (!(vcpu->arch.ctrl & 1)) + mtspr(SPRN_CTRLT, 1); + +#ifdef CONFIG_ALTIVEC + if (cpu_has_feature(CPU_FTR_ALTIVEC) && + vcpu->arch.vrsave != current->thread.vrsave) + mtspr(SPRN_VRSAVE, current->thread.vrsave); +#endif + if (vcpu->arch.hfscr & HFSCR_EBB) { + if (vcpu->arch.bescr != current->thread.bescr) + mtspr(SPRN_BESCR, current->thread.bescr); + if (vcpu->arch.ebbhr != current->thread.ebbhr) + mtspr(SPRN_EBBHR, current->thread.ebbhr); + if (vcpu->arch.ebbrr != current->thread.ebbrr) + mtspr(SPRN_EBBRR, current->thread.ebbrr); + + if (!vcpu->arch.nested) { + /* + * This is like load_fp in context switching, turn off + * the facility after it wraps the u8 to try avoiding + * saving and restoring the registers each partition + * switch. + */ + vcpu->arch.load_ebb++; + if (!vcpu->arch.load_ebb) + vcpu->arch.hfscr &= ~HFSCR_EBB; + } + } + + if (vcpu->arch.tar != current->thread.tar) + mtspr(SPRN_TAR, current->thread.tar); +} +EXPORT_SYMBOL_GPL(restore_p9_host_os_sprs); + +#ifdef CONFIG_KVM_BOOK3S_HV_P9_TIMING +void accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator *next) +{ + struct kvmppc_vcore *vc = vcpu->arch.vcore; + struct kvmhv_tb_accumulator *curr; + u64 tb = mftb() - vc->tb_offset_applied; + u64 prev_tb; + u64 delta; + u64 seq; + + curr = vcpu->arch.cur_activity; + vcpu->arch.cur_activity = next; + prev_tb = vcpu->arch.cur_tb_start; + vcpu->arch.cur_tb_start = tb; + + if (!curr) + return; + + delta = tb - prev_tb; + + seq = curr->seqcount; + curr->seqcount = seq + 1; + smp_wmb(); + curr->tb_total += delta; + if (seq == 0 || delta < curr->tb_min) + curr->tb_min = delta; + if (delta > curr->tb_max) + curr->tb_max = delta; + smp_wmb(); + curr->seqcount = seq + 2; +} +EXPORT_SYMBOL_GPL(accumulate_time); +#endif + +static inline u64 mfslbv(unsigned int idx) +{ + u64 slbev; + + asm volatile("slbmfev %0,%1" : "=r" (slbev) : "r" (idx)); + + return slbev; +} + +static inline u64 mfslbe(unsigned int idx) +{ + u64 slbee; + + asm volatile("slbmfee %0,%1" : "=r" (slbee) : "r" (idx)); + + return slbee; +} + +static inline void mtslb(u64 slbee, u64 slbev) +{ + asm volatile("slbmte %0,%1" :: "r" (slbev), "r" (slbee)); +} + +static inline void clear_slb_entry(unsigned int idx) +{ + mtslb(idx, 0); +} + +static inline void slb_clear_invalidate_partition(void) +{ + clear_slb_entry(0); + asm volatile(PPC_SLBIA(6)); +} + +/* + * Malicious or buggy radix guests may have inserted SLB entries + * (only 0..3 because radix always runs with UPRT=1), so these must + * be cleared here to avoid side-channels. slbmte is used rather + * than slbia, as it won't clear cached translations. + */ +static void radix_clear_slb(void) +{ + int i; + + for (i = 0; i < 4; i++) + clear_slb_entry(i); +} + +static void switch_mmu_to_guest_radix(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr) +{ + struct kvm_nested_guest *nested = vcpu->arch.nested; + u32 lpid; + u32 pid; + + lpid = nested ? nested->shadow_lpid : kvm->arch.lpid; + pid = kvmppc_get_pid(vcpu); + + /* + * Prior memory accesses to host PID Q3 must be completed before we + * start switching, and stores must be drained to avoid not-my-LPAR + * logic (see switch_mmu_to_host). + */ + asm volatile("hwsync" ::: "memory"); + isync(); + mtspr(SPRN_LPID, lpid); + mtspr(SPRN_LPCR, lpcr); + mtspr(SPRN_PID, pid); + /* + * isync not required here because we are HRFID'ing to guest before + * any guest context access, which is context synchronising. + */ +} + +static void switch_mmu_to_guest_hpt(struct kvm *kvm, struct kvm_vcpu *vcpu, u64 lpcr) +{ + u32 lpid; + u32 pid; + int i; + + lpid = kvm->arch.lpid; + pid = kvmppc_get_pid(vcpu); + + /* + * See switch_mmu_to_guest_radix. ptesync should not be required here + * even if the host is in HPT mode because speculative accesses would + * not cause RC updates (we are in real mode). + */ + asm volatile("hwsync" ::: "memory"); + isync(); + mtspr(SPRN_LPID, lpid); + mtspr(SPRN_LPCR, lpcr); + mtspr(SPRN_PID, pid); + + for (i = 0; i < vcpu->arch.slb_max; i++) + mtslb(vcpu->arch.slb[i].orige, vcpu->arch.slb[i].origv); + /* + * isync not required here, see switch_mmu_to_guest_radix. + */ +} + +static void switch_mmu_to_host(struct kvm *kvm, u32 pid) +{ + u32 lpid = kvm->arch.host_lpid; + u64 lpcr = kvm->arch.host_lpcr; + + /* + * The guest has exited, so guest MMU context is no longer being + * non-speculatively accessed, but a hwsync is needed before the + * mtLPIDR / mtPIDR switch, in order to ensure all stores are drained, + * so the not-my-LPAR tlbie logic does not overlook them. + */ + asm volatile("hwsync" ::: "memory"); + isync(); + mtspr(SPRN_PID, pid); + mtspr(SPRN_LPID, lpid); + mtspr(SPRN_LPCR, lpcr); + /* + * isync is not required after the switch, because mtmsrd with L=0 + * is performed after this switch, which is context synchronising. + */ + + if (!radix_enabled()) + slb_restore_bolted_realmode(); +} + +static void save_clear_host_mmu(struct kvm *kvm) +{ + if (!radix_enabled()) { + /* + * Hash host could save and restore host SLB entries to + * reduce SLB fault overheads of VM exits, but for now the + * existing code clears all entries and restores just the + * bolted ones when switching back to host. + */ + slb_clear_invalidate_partition(); + } +} + +static void save_clear_guest_mmu(struct kvm *kvm, struct kvm_vcpu *vcpu) +{ + if (kvm_is_radix(kvm)) { + radix_clear_slb(); + } else { + int i; + int nr = 0; + + /* + * This must run before switching to host (radix host can't + * access all SLBs). + */ + for (i = 0; i < vcpu->arch.slb_nr; i++) { + u64 slbee, slbev; + + slbee = mfslbe(i); + if (slbee & SLB_ESID_V) { + slbev = mfslbv(i); + vcpu->arch.slb[nr].orige = slbee | i; + vcpu->arch.slb[nr].origv = slbev; + nr++; + } + } + vcpu->arch.slb_max = nr; + slb_clear_invalidate_partition(); + } +} + +static void flush_guest_tlb(struct kvm *kvm) +{ + unsigned long rb, set; + + rb = PPC_BIT(52); /* IS = 2 */ + if (kvm_is_radix(kvm)) { + /* R=1 PRS=1 RIC=2 */ + asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1) + : : "r" (rb), "i" (1), "i" (1), "i" (2), + "r" (0) : "memory"); + for (set = 1; set < kvm->arch.tlb_sets; ++set) { + rb += PPC_BIT(51); /* increment set number */ + /* R=1 PRS=1 RIC=0 */ + asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1) + : : "r" (rb), "i" (1), "i" (1), "i" (0), + "r" (0) : "memory"); + } + asm volatile("ptesync": : :"memory"); + // POWER9 congruence-class TLBIEL leaves ERAT. Flush it now. + asm volatile(PPC_RADIX_INVALIDATE_ERAT_GUEST : : :"memory"); + } else { + for (set = 0; set < kvm->arch.tlb_sets; ++set) { + /* R=0 PRS=0 RIC=0 */ + asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1) + : : "r" (rb), "i" (0), "i" (0), "i" (0), + "r" (0) : "memory"); + rb += PPC_BIT(51); /* increment set number */ + } + asm volatile("ptesync": : :"memory"); + // POWER9 congruence-class TLBIEL leaves ERAT. Flush it now. + asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT : : :"memory"); + } +} + +static void check_need_tlb_flush(struct kvm *kvm, int pcpu, + struct kvm_nested_guest *nested) +{ + cpumask_t *need_tlb_flush; + bool all_set = true; + int i; + + if (nested) + need_tlb_flush = &nested->need_tlb_flush; + else + need_tlb_flush = &kvm->arch.need_tlb_flush; + + if (likely(!cpumask_test_cpu(pcpu, need_tlb_flush))) + return; + + /* + * Individual threads can come in here, but the TLB is shared between + * the 4 threads in a core, hence invalidating on one thread + * invalidates for all, so only invalidate the first time (if all bits + * were set. The others must still execute a ptesync. + * + * If a race occurs and two threads do the TLB flush, that is not a + * problem, just sub-optimal. + */ + for (i = cpu_first_tlb_thread_sibling(pcpu); + i <= cpu_last_tlb_thread_sibling(pcpu); + i += cpu_tlb_thread_sibling_step()) { + if (!cpumask_test_cpu(i, need_tlb_flush)) { + all_set = false; + break; + } + } + if (all_set) + flush_guest_tlb(kvm); + else + asm volatile("ptesync" ::: "memory"); + + /* Clear the bit after the TLB flush */ + cpumask_clear_cpu(pcpu, need_tlb_flush); +} + +unsigned long kvmppc_msr_hard_disable_set_facilities(struct kvm_vcpu *vcpu, unsigned long msr) +{ + unsigned long msr_needed = 0; + + msr &= ~MSR_EE; + + /* MSR bits may have been cleared by context switch so must recheck */ + if (IS_ENABLED(CONFIG_PPC_FPU)) + msr_needed |= MSR_FP; + if (cpu_has_feature(CPU_FTR_ALTIVEC)) + msr_needed |= MSR_VEC; + if (cpu_has_feature(CPU_FTR_VSX)) + msr_needed |= MSR_VSX; + if ((cpu_has_feature(CPU_FTR_TM) || + cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) && + (vcpu->arch.hfscr & HFSCR_TM)) + msr_needed |= MSR_TM; + + /* + * This could be combined with MSR[RI] clearing, but that expands + * the unrecoverable window. It would be better to cover unrecoverable + * with KVM bad interrupt handling rather than use MSR[RI] at all. + * + * Much more difficult and less worthwhile to combine with IR/DR + * disable. + */ + if ((msr & msr_needed) != msr_needed) { + msr |= msr_needed; + __mtmsrd(msr, 0); + } else { + __hard_irq_disable(); + } + local_paca->irq_happened |= PACA_IRQ_HARD_DIS; + + return msr; +} +EXPORT_SYMBOL_GPL(kvmppc_msr_hard_disable_set_facilities); + +int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpcr, u64 *tb) +{ + struct p9_host_os_sprs host_os_sprs; + struct kvm *kvm = vcpu->kvm; + struct kvm_nested_guest *nested = vcpu->arch.nested; + struct kvmppc_vcore *vc = vcpu->arch.vcore; + s64 hdec, dec; + u64 purr, spurr; + u64 *exsave; + int trap; + unsigned long msr; + unsigned long host_hfscr; + unsigned long host_ciabr; + unsigned long host_dawr0; + unsigned long host_dawrx0; + unsigned long host_psscr; + unsigned long host_hpsscr; + unsigned long host_pidr; + unsigned long host_dawr1; + unsigned long host_dawrx1; + unsigned long dpdes; + + hdec = time_limit - *tb; + if (hdec < 0) + return BOOK3S_INTERRUPT_HV_DECREMENTER; + + WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_HV); + WARN_ON_ONCE(!(vcpu->arch.shregs.msr & MSR_ME)); + + vcpu->arch.ceded = 0; + + /* Save MSR for restore, with EE clear. */ + msr = mfmsr() & ~MSR_EE; + + host_hfscr = mfspr(SPRN_HFSCR); + host_ciabr = mfspr(SPRN_CIABR); + host_psscr = mfspr(SPRN_PSSCR_PR); + if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) + host_hpsscr = mfspr(SPRN_PSSCR); + host_pidr = mfspr(SPRN_PID); + + if (dawr_enabled()) { + host_dawr0 = mfspr(SPRN_DAWR0); + host_dawrx0 = mfspr(SPRN_DAWRX0); + if (cpu_has_feature(CPU_FTR_DAWR1)) { + host_dawr1 = mfspr(SPRN_DAWR1); + host_dawrx1 = mfspr(SPRN_DAWRX1); + } + } + + local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR); + local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR); + + save_p9_host_os_sprs(&host_os_sprs); + + msr = kvmppc_msr_hard_disable_set_facilities(vcpu, msr); + if (lazy_irq_pending()) { + trap = 0; + goto out; + } + + if (unlikely(load_vcpu_state(vcpu, &host_os_sprs))) + msr = mfmsr(); /* MSR may have been updated */ + + if (vc->tb_offset) { + u64 new_tb = *tb + vc->tb_offset; + mtspr(SPRN_TBU40, new_tb); + if ((mftb() & 0xffffff) < (new_tb & 0xffffff)) { + new_tb += 0x1000000; + mtspr(SPRN_TBU40, new_tb); + } + *tb = new_tb; + vc->tb_offset_applied = vc->tb_offset; + } + + mtspr(SPRN_VTB, vc->vtb); + mtspr(SPRN_PURR, vcpu->arch.purr); + mtspr(SPRN_SPURR, vcpu->arch.spurr); + + if (vc->pcr) + mtspr(SPRN_PCR, vc->pcr | PCR_MASK); + if (vcpu->arch.doorbell_request) { + vcpu->arch.doorbell_request = 0; + mtspr(SPRN_DPDES, 1); + } + + if (dawr_enabled()) { + if (vcpu->arch.dawr0 != host_dawr0) + mtspr(SPRN_DAWR0, vcpu->arch.dawr0); + if (vcpu->arch.dawrx0 != host_dawrx0) + mtspr(SPRN_DAWRX0, vcpu->arch.dawrx0); + if (cpu_has_feature(CPU_FTR_DAWR1)) { + if (vcpu->arch.dawr1 != host_dawr1) + mtspr(SPRN_DAWR1, vcpu->arch.dawr1); + if (vcpu->arch.dawrx1 != host_dawrx1) + mtspr(SPRN_DAWRX1, vcpu->arch.dawrx1); + } + } + if (vcpu->arch.ciabr != host_ciabr) + mtspr(SPRN_CIABR, vcpu->arch.ciabr); + + + if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) { + mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC | + (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG)); + } else { + if (vcpu->arch.psscr != host_psscr) + mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr); + } + + mtspr(SPRN_HFSCR, vcpu->arch.hfscr); + + mtspr(SPRN_HSRR0, vcpu->arch.regs.nip); + mtspr(SPRN_HSRR1, (vcpu->arch.shregs.msr & ~MSR_HV) | MSR_ME); + + /* + * On POWER9 DD2.1 and below, sometimes on a Hypervisor Data Storage + * Interrupt (HDSI) the HDSISR is not be updated at all. + * + * To work around this we put a canary value into the HDSISR before + * returning to a guest and then check for this canary when we take a + * HDSI. If we find the canary on a HDSI, we know the hardware didn't + * update the HDSISR. In this case we return to the guest to retake the + * HDSI which should correctly update the HDSISR the second time HDSI + * entry. + * + * The "radix prefetch bug" test can be used to test for this bug, as + * it also exists fo DD2.1 and below. + */ + if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) + mtspr(SPRN_HDSISR, HDSISR_CANARY); + + mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0); + mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1); + mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2); + mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3); + + /* + * It might be preferable to load_vcpu_state here, in order to get the + * GPR/FP register loads executing in parallel with the previous mtSPR + * instructions, but for now that can't be done because the TM handling + * in load_vcpu_state can change some SPRs and vcpu state (nip, msr). + * But TM could be split out if this would be a significant benefit. + */ + + /* + * MSR[RI] does not need to be cleared (and is not, for radix guests + * with no prefetch bug), because in_guest is set. If we take a SRESET + * or MCE with in_guest set but still in HV mode, then + * kvmppc_p9_bad_interrupt handles the interrupt, which effectively + * clears MSR[RI] and doesn't return. + */ + WRITE_ONCE(local_paca->kvm_hstate.in_guest, KVM_GUEST_MODE_HV_P9); + barrier(); /* Open in_guest critical section */ + + /* + * Hash host, hash guest, or radix guest with prefetch bug, all have + * to disable the MMU before switching to guest MMU state. + */ + if (!radix_enabled() || !kvm_is_radix(kvm) || + cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) + __mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0); + + save_clear_host_mmu(kvm); + + if (kvm_is_radix(kvm)) + switch_mmu_to_guest_radix(kvm, vcpu, lpcr); + else + switch_mmu_to_guest_hpt(kvm, vcpu, lpcr); + + /* TLBIEL uses LPID=LPIDR, so run this after setting guest LPID */ + check_need_tlb_flush(kvm, vc->pcpu, nested); + + /* + * P9 suppresses the HDEC exception when LPCR[HDICE] = 0, + * so set guest LPCR (with HDICE) before writing HDEC. + */ + mtspr(SPRN_HDEC, hdec); + + mtspr(SPRN_DEC, vcpu->arch.dec_expires - *tb); + +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +tm_return_to_guest: +#endif + mtspr(SPRN_DAR, vcpu->arch.shregs.dar); + mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr); + mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0); + mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1); + + switch_pmu_to_guest(vcpu, &host_os_sprs); + accumulate_time(vcpu, &vcpu->arch.in_guest); + + kvmppc_p9_enter_guest(vcpu); + + accumulate_time(vcpu, &vcpu->arch.guest_exit); + switch_pmu_to_host(vcpu, &host_os_sprs); + + /* XXX: Could get these from r11/12 and paca exsave instead */ + vcpu->arch.shregs.srr0 = mfspr(SPRN_SRR0); + vcpu->arch.shregs.srr1 = mfspr(SPRN_SRR1); + vcpu->arch.shregs.dar = mfspr(SPRN_DAR); + vcpu->arch.shregs.dsisr = mfspr(SPRN_DSISR); + + /* 0x2 bit for HSRR is only used by PR and P7/8 HV paths, clear it */ + trap = local_paca->kvm_hstate.scratch0 & ~0x2; + + if (likely(trap > BOOK3S_INTERRUPT_MACHINE_CHECK)) + exsave = local_paca->exgen; + else if (trap == BOOK3S_INTERRUPT_SYSTEM_RESET) + exsave = local_paca->exnmi; + else /* trap == 0x200 */ + exsave = local_paca->exmc; + + vcpu->arch.regs.gpr[1] = local_paca->kvm_hstate.scratch1; + vcpu->arch.regs.gpr[3] = local_paca->kvm_hstate.scratch2; + + /* + * After reading machine check regs (DAR, DSISR, SRR0/1) and hstate + * scratch (which we need to move into exsave to make re-entrant vs + * SRESET/MCE), register state is protected from reentrancy. However + * timebase, MMU, among other state is still set to guest, so don't + * enable MSR[RI] here. It gets enabled at the end, after in_guest + * is cleared. + * + * It is possible an NMI could come in here, which is why it is + * important to save the above state early so it can be debugged. + */ + + vcpu->arch.regs.gpr[9] = exsave[EX_R9/sizeof(u64)]; + vcpu->arch.regs.gpr[10] = exsave[EX_R10/sizeof(u64)]; + vcpu->arch.regs.gpr[11] = exsave[EX_R11/sizeof(u64)]; + vcpu->arch.regs.gpr[12] = exsave[EX_R12/sizeof(u64)]; + vcpu->arch.regs.gpr[13] = exsave[EX_R13/sizeof(u64)]; + vcpu->arch.ppr = exsave[EX_PPR/sizeof(u64)]; + vcpu->arch.cfar = exsave[EX_CFAR/sizeof(u64)]; + vcpu->arch.regs.ctr = exsave[EX_CTR/sizeof(u64)]; + + vcpu->arch.last_inst = KVM_INST_FETCH_FAILED; + + if (unlikely(trap == BOOK3S_INTERRUPT_MACHINE_CHECK)) { + vcpu->arch.fault_dar = exsave[EX_DAR/sizeof(u64)]; + vcpu->arch.fault_dsisr = exsave[EX_DSISR/sizeof(u64)]; + kvmppc_realmode_machine_check(vcpu); + + } else if (unlikely(trap == BOOK3S_INTERRUPT_HMI)) { + kvmppc_p9_realmode_hmi_handler(vcpu); + + } else if (trap == BOOK3S_INTERRUPT_H_EMUL_ASSIST) { + vcpu->arch.emul_inst = mfspr(SPRN_HEIR); + + } else if (trap == BOOK3S_INTERRUPT_H_DATA_STORAGE) { + vcpu->arch.fault_dar = exsave[EX_DAR/sizeof(u64)]; + vcpu->arch.fault_dsisr = exsave[EX_DSISR/sizeof(u64)]; + vcpu->arch.fault_gpa = mfspr(SPRN_ASDR); + + } else if (trap == BOOK3S_INTERRUPT_H_INST_STORAGE) { + vcpu->arch.fault_gpa = mfspr(SPRN_ASDR); + + } else if (trap == BOOK3S_INTERRUPT_H_FAC_UNAVAIL) { + vcpu->arch.hfscr = mfspr(SPRN_HFSCR); + +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + /* + * Softpatch interrupt for transactional memory emulation cases + * on POWER9 DD2.2. This is early in the guest exit path - we + * haven't saved registers or done a treclaim yet. + */ + } else if (trap == BOOK3S_INTERRUPT_HV_SOFTPATCH) { + vcpu->arch.emul_inst = mfspr(SPRN_HEIR); + + /* + * The cases we want to handle here are those where the guest + * is in real suspend mode and is trying to transition to + * transactional mode. + */ + if (!local_paca->kvm_hstate.fake_suspend && + (vcpu->arch.shregs.msr & MSR_TS_S)) { + if (kvmhv_p9_tm_emulation_early(vcpu)) { + /* + * Go straight back into the guest with the + * new NIP/MSR as set by TM emulation. + */ + mtspr(SPRN_HSRR0, vcpu->arch.regs.nip); + mtspr(SPRN_HSRR1, vcpu->arch.shregs.msr); + goto tm_return_to_guest; + } + } +#endif + } + + /* Advance host PURR/SPURR by the amount used by guest */ + purr = mfspr(SPRN_PURR); + spurr = mfspr(SPRN_SPURR); + local_paca->kvm_hstate.host_purr += purr - vcpu->arch.purr; + local_paca->kvm_hstate.host_spurr += spurr - vcpu->arch.spurr; + vcpu->arch.purr = purr; + vcpu->arch.spurr = spurr; + + vcpu->arch.ic = mfspr(SPRN_IC); + vcpu->arch.pid = mfspr(SPRN_PID); + vcpu->arch.psscr = mfspr(SPRN_PSSCR_PR); + + vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0); + vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1); + vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2); + vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3); + + dpdes = mfspr(SPRN_DPDES); + if (dpdes) + vcpu->arch.doorbell_request = 1; + + vc->vtb = mfspr(SPRN_VTB); + + dec = mfspr(SPRN_DEC); + if (!(lpcr & LPCR_LD)) /* Sign extend if not using large decrementer */ + dec = (s32) dec; + *tb = mftb(); + vcpu->arch.dec_expires = dec + *tb; + + if (vc->tb_offset_applied) { + u64 new_tb = *tb - vc->tb_offset_applied; + mtspr(SPRN_TBU40, new_tb); + if ((mftb() & 0xffffff) < (new_tb & 0xffffff)) { + new_tb += 0x1000000; + mtspr(SPRN_TBU40, new_tb); + } + *tb = new_tb; + vc->tb_offset_applied = 0; + } + + save_clear_guest_mmu(kvm, vcpu); + switch_mmu_to_host(kvm, host_pidr); + + /* + * Enable MSR here in order to have facilities enabled to save + * guest registers. This enables MMU (if we were in realmode), so + * only switch MMU on after the MMU is switched to host, to avoid + * the P9_RADIX_PREFETCH_BUG or hash guest context. + */ + if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && + vcpu->arch.shregs.msr & MSR_TS_MASK) + msr |= MSR_TS_S; + __mtmsrd(msr, 0); + + store_vcpu_state(vcpu); + + mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr); + mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr); + + if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) { + /* Preserve PSSCR[FAKE_SUSPEND] until we've called kvmppc_save_tm_hv */ + mtspr(SPRN_PSSCR, host_hpsscr | + (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG)); + } + + mtspr(SPRN_HFSCR, host_hfscr); + if (vcpu->arch.ciabr != host_ciabr) + mtspr(SPRN_CIABR, host_ciabr); + + if (dawr_enabled()) { + if (vcpu->arch.dawr0 != host_dawr0) + mtspr(SPRN_DAWR0, host_dawr0); + if (vcpu->arch.dawrx0 != host_dawrx0) + mtspr(SPRN_DAWRX0, host_dawrx0); + if (cpu_has_feature(CPU_FTR_DAWR1)) { + if (vcpu->arch.dawr1 != host_dawr1) + mtspr(SPRN_DAWR1, host_dawr1); + if (vcpu->arch.dawrx1 != host_dawrx1) + mtspr(SPRN_DAWRX1, host_dawrx1); + } + } + + if (dpdes) + mtspr(SPRN_DPDES, 0); + if (vc->pcr) + mtspr(SPRN_PCR, PCR_MASK); + + /* HDEC must be at least as large as DEC, so decrementer_max fits */ + mtspr(SPRN_HDEC, decrementer_max); + + timer_rearm_host_dec(*tb); + + restore_p9_host_os_sprs(vcpu, &host_os_sprs); + + barrier(); /* Close in_guest critical section */ + WRITE_ONCE(local_paca->kvm_hstate.in_guest, KVM_GUEST_MODE_NONE); + /* Interrupts are recoverable at this point */ + + /* + * cp_abort is required if the processor supports local copy-paste + * to clear the copy buffer that was under control of the guest. + */ + if (cpu_has_feature(CPU_FTR_ARCH_31)) + asm volatile(PPC_CP_ABORT); + +out: + return trap; +} +EXPORT_SYMBOL_GPL(kvmhv_vcpu_entry_p9); |