| Message ID | 1342760362-10822-1-git-send-email-Bharat.Bhushan@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Please ignore this as I forget to get [v5] is subject.. Thanks -Bharat > -----Original Message----- > From: Bhushan Bharat-R65777 > Sent: Friday, July 20, 2012 10:29 AM > To: kvm-ppc@vger.kernel.org; kvm@vger.kernel.org; agraf@suse.de > Cc: Bhushan Bharat-R65777 > Subject: [PATCH 2/2] KVM: PPC: booke: Add watchdog emulation > > This patch adds the watchdog emulation in KVM. The watchdog emulation is enabled > by KVM_ENABLE_CAP(KVM_CAP_PPC_WDT) ioctl. > The kernel timer are used for watchdog emulation and emulates h/w watchdog state > machine. On watchdog timer expiry, it exit to QEMU if TCR.WRC is non ZERO. QEMU > can reset/shutdown etc depending upon how it is configured. > > Signed-off-by: Liu Yu <yu.liu@freescale.com> > Signed-off-by: Scott Wood <scottwood@freescale.com> > Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> > [bharat.bhushan@freescale.com: reworked patch] > > --- > v5: > - Checking that TSR_ENW/TSR_WIS are still set on KVM_EXIT_WATCHDOG. > - Moved watchdog_next_timeout() in lock. > > v4: > - in v3 i forgot to add Scott Wood and Liu Yu signoff > > v3: > - Using KVM_REQ_WATCHDOG for userspace exit. > - TSR changes left for vcpu thread. > - Other review comments on v2 > > arch/powerpc/include/asm/kvm_host.h | 3 + > arch/powerpc/include/asm/kvm_ppc.h | 3 + > arch/powerpc/include/asm/reg_booke.h | 7 ++ > arch/powerpc/kvm/booke.c | 140 ++++++++++++++++++++++++++++++++++ > arch/powerpc/kvm/booke_emulate.c | 8 ++ > arch/powerpc/kvm/powerpc.c | 19 +++++- > include/linux/kvm.h | 2 + > include/linux/kvm_host.h | 1 + > 8 files changed, 182 insertions(+), 1 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_host.h > b/arch/powerpc/include/asm/kvm_host.h > index 50ea12f..43cac48 100644 > --- a/arch/powerpc/include/asm/kvm_host.h > +++ b/arch/powerpc/include/asm/kvm_host.h > @@ -467,6 +467,8 @@ struct kvm_vcpu_arch { > ulong fault_esr; > ulong queued_dear; > ulong queued_esr; > + spinlock_t wdt_lock; > + struct timer_list wdt_timer; > u32 tlbcfg[4]; > u32 mmucfg; > u32 epr; > @@ -482,6 +484,7 @@ struct kvm_vcpu_arch { > u8 osi_needed; > u8 osi_enabled; > u8 papr_enabled; > + u8 watchdog_enabled; > u8 sane; > u8 cpu_type; > u8 hcall_needed; > diff --git a/arch/powerpc/include/asm/kvm_ppc.h > b/arch/powerpc/include/asm/kvm_ppc.h > index 0124937..e5cf4b9 100644 > --- a/arch/powerpc/include/asm/kvm_ppc.h > +++ b/arch/powerpc/include/asm/kvm_ppc.h > @@ -67,6 +67,7 @@ extern int kvmppc_emulate_mmio(struct kvm_run *run, struct > kvm_vcpu *vcpu); extern void kvmppc_emulate_dec(struct kvm_vcpu *vcpu); extern > u32 kvmppc_get_dec(struct kvm_vcpu *vcpu, u64 tb); extern void > kvmppc_decrementer_func(unsigned long data); > +extern void kvmppc_watchdog_func(unsigned long data); > extern int kvmppc_sanity_check(struct kvm_vcpu *vcpu); > > /* Core-specific hooks */ > @@ -104,6 +105,8 @@ extern void kvmppc_core_queue_external(struct kvm_vcpu > *vcpu, > struct kvm_interrupt *irq); extern void > kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu, > struct kvm_interrupt *irq); > +extern void kvmppc_core_queue_watchdog(struct kvm_vcpu *vcpu); extern > +void kvmppc_core_dequeue_watchdog(struct kvm_vcpu *vcpu); > > extern int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu, > unsigned int op, int *advance); diff --git > a/arch/powerpc/include/asm/reg_booke.h b/arch/powerpc/include/asm/reg_booke.h > index 2d916c4..e07e6af 100644 > --- a/arch/powerpc/include/asm/reg_booke.h > +++ b/arch/powerpc/include/asm/reg_booke.h > @@ -539,6 +539,13 @@ > #define TCR_FIE 0x00800000 /* FIT Interrupt Enable */ > #define TCR_ARE 0x00400000 /* Auto Reload Enable */ > > +#ifdef CONFIG_E500 > +#define TCR_GET_WP(tcr) ((((tcr) & 0xC0000000) >> 30) | \ > + (((tcr) & 0x1E0000) >> 15)) > +#else > +#define TCR_GET_WP(tcr) (((tcr) & 0xC0000000) >> 30) #endif > + > /* Bit definitions for the TSR. */ > #define TSR_ENW 0x80000000 /* Enable Next Watchdog */ > #define TSR_WIS 0x40000000 /* WDT Interrupt Status */ > diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index > d25a097..71b4ce9 100644 > --- a/arch/powerpc/kvm/booke.c > +++ b/arch/powerpc/kvm/booke.c > @@ -206,6 +206,16 @@ void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu, > clear_bit(BOOKE_IRQPRIO_EXTERNAL_LEVEL, &vcpu->arch.pending_exceptions); > } > > +void kvmppc_core_queue_watchdog(struct kvm_vcpu *vcpu) { > + kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_WATCHDOG); } > + > +void kvmppc_core_dequeue_watchdog(struct kvm_vcpu *vcpu) { > + clear_bit(BOOKE_IRQPRIO_WATCHDOG, &vcpu->arch.pending_exceptions); } > + > static void set_guest_srr(struct kvm_vcpu *vcpu, unsigned long srr0, u32 srr1) > { #ifdef CONFIG_KVM_BOOKE_HV @@ -325,6 +335,7 @@ static int > kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, > msr_mask = MSR_CE | MSR_ME | MSR_DE; > int_class = INT_CLASS_NONCRIT; > break; > + case BOOKE_IRQPRIO_WATCHDOG: > case BOOKE_IRQPRIO_CRITICAL: > case BOOKE_IRQPRIO_DBELL_CRIT: > allowed = vcpu->arch.shared->msr & MSR_CE; @@ -404,12 +415,113 @@ > static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, > return allowed; > } > > +/* > + * Return the number of jiffies until the next timeout. If the timeout > +is > + * longer than the NEXT_TIMER_MAX_DELTA, then return > +NEXT_TIMER_MAX_DELTA > + * because the larger value can break the timer APIs. > + */ > +static unsigned long watchdog_next_timeout(struct kvm_vcpu *vcpu) { > + u64 tb, wdt_tb, wdt_ticks = 0; > + u64 nr_jiffies = 0; > + u32 period = TCR_GET_WP(vcpu->arch.tcr); > + > + wdt_tb = 1ULL << (63 - period); > + tb = get_tb(); > + /* > + * The watchdog timeout will hapeen when TB bit corresponding > + * to watchdog will toggle from 0 to 1. > + */ > + if (tb & wdt_tb) > + wdt_ticks = wdt_tb; > + > + wdt_ticks += wdt_tb - (tb & (wdt_tb - 1)); > + > + /* Convert timebase ticks to jiffies */ > + nr_jiffies = wdt_ticks; > + > + if (do_div(nr_jiffies, tb_ticks_per_jiffy)) > + nr_jiffies++; > + > + return min_t(unsigned long long, nr_jiffies, NEXT_TIMER_MAX_DELTA); } > + > +static void arm_next_watchdog(struct kvm_vcpu *vcpu) { > + unsigned long nr_jiffies; > + > + spin_lock(&vcpu->arch.wdt_lock); > + nr_jiffies = watchdog_next_timeout(vcpu); > + /* > + * If the number of jiffies of watchdog timer >= NEXT_TIMER_MAX_DELTA > + * then do not run the watchdog timer as this can break timer APIs. > + */ > + if (nr_jiffies < NEXT_TIMER_MAX_DELTA) > + mod_timer(&vcpu->arch.wdt_timer, jiffies + nr_jiffies); > + else > + del_timer(&vcpu->arch.wdt_timer); > + spin_unlock(&vcpu->arch.wdt_lock); > +} > + > +void kvmppc_watchdog_func(unsigned long data) { > + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; > + u32 tsr, new_tsr; > + int final; > + > + do { > + new_tsr = tsr = vcpu->arch.tsr; > + final = 0; > + > + /* Time out event */ > + if (tsr & TSR_ENW) { > + if (tsr & TSR_WIS) > + final = 1; > + else > + new_tsr = tsr | TSR_WIS; > + } else { > + new_tsr = tsr | TSR_ENW; > + } > + } while (cmpxchg(&vcpu->arch.tsr, tsr, new_tsr) != tsr); > + > + if (new_tsr & TSR_WIS) { > + smp_wmb(); > + kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); > + kvm_vcpu_kick(vcpu); > + } > + > + /* > + * If this is final watchdog expiry and some action is required > + * then exit to userspace. > + */ > + if (final && (vcpu->arch.tcr & TCR_WRC_MASK) && > + vcpu->arch.watchdog_enabled) { > + smp_wmb(); > + kvm_make_request(KVM_REQ_WATCHDOG, vcpu); > + kvm_vcpu_kick(vcpu); > + } > + > + /* > + * Stop running the watchdog timer after final expiration to > + * prevent the host from being flooded with timers if the > + * guest sets a short period. > + * Timers will resume when TSR/TCR is updated next time. > + */ > + if (!final) > + arm_next_watchdog(vcpu); > +} > + > static void update_timer_ints(struct kvm_vcpu *vcpu) { > if ((vcpu->arch.tcr & TCR_DIE) && (vcpu->arch.tsr & TSR_DIS)) > kvmppc_core_queue_dec(vcpu); > else > kvmppc_core_dequeue_dec(vcpu); > + > + if ((vcpu->arch.tcr & TCR_WIE) && (vcpu->arch.tsr & TSR_WIS)) > + kvmppc_core_queue_watchdog(vcpu); > + else > + kvmppc_core_dequeue_watchdog(vcpu); > } > > static void kvmppc_core_check_exceptions(struct kvm_vcpu *vcpu) @@ -516,6 > +628,13 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) > goto out; > } > > + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && > + (vcpu->arch.tsr & (TSR_ENW | TSR_WIS))) { > + kvm_run->exit_reason = KVM_EXIT_WATCHDOG; > + ret = 0; > + goto out; > + } > + > kvm_guest_enter(); > > #ifdef CONFIG_PPC_FPU > @@ -978,6 +1097,12 @@ int kvmppc_handle_exit(struct kvm_run *run, struct > kvm_vcpu *vcpu, > } > } > > + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && > + (vcpu->arch.tsr & (TSR_ENW | TSR_WIS))) { > + run->exit_reason = KVM_EXIT_WATCHDOG; > + r = RESUME_HOST | (r & RESUME_FLAG_NV); > + } > + > return r; > } > > @@ -1106,7 +1231,13 @@ static int set_sregs_base(struct kvm_vcpu *vcpu, > } > > if (sregs->u.e.update_special & KVM_SREGS_E_UPDATE_TSR) { > + u32 old_tsr = vcpu->arch.tsr; > + > vcpu->arch.tsr = sregs->u.e.tsr; > + > + if ((old_tsr ^ vcpu->arch.tsr) & (TSR_ENW | TSR_WIS)) > + arm_next_watchdog(vcpu); > + > update_timer_ints(vcpu); > } > > @@ -1267,6 +1398,7 @@ void kvmppc_core_commit_memory_region(struct kvm *kvm, > void kvmppc_set_tcr(struct kvm_vcpu *vcpu, u32 new_tcr) { > vcpu->arch.tcr = new_tcr; > + arm_next_watchdog(vcpu); > update_timer_ints(vcpu); > } > > @@ -1281,6 +1413,14 @@ void kvmppc_set_tsr_bits(struct kvm_vcpu *vcpu, u32 > tsr_bits) void kvmppc_clr_tsr_bits(struct kvm_vcpu *vcpu, u32 tsr_bits) { > clear_bits(tsr_bits, &vcpu->arch.tsr); > + > + /* > + * We may have stopped the watchdog due to > + * being stuck on final expiration. > + */ > + if (tsr_bits & (TSR_ENW | TSR_WIS)) > + arm_next_watchdog(vcpu); > + > update_timer_ints(vcpu); > } > > diff --git a/arch/powerpc/kvm/booke_emulate.c b/arch/powerpc/kvm/booke_emulate.c > index 12834bb..5a66ade 100644 > --- a/arch/powerpc/kvm/booke_emulate.c > +++ b/arch/powerpc/kvm/booke_emulate.c > @@ -145,6 +145,14 @@ int kvmppc_booke_emulate_mtspr(struct kvm_vcpu *vcpu, int > sprn, ulong spr_val) > kvmppc_clr_tsr_bits(vcpu, spr_val); > break; > case SPRN_TCR: > + /* > + * WRC is a 2-bit field that is supposed to preserve its > + * value once written to non-zero. > + */ > + if (vcpu->arch.tcr & TCR_WRC_MASK) { > + spr_val &= ~TCR_WRC_MASK; > + spr_val |= vcpu->arch.tcr & TCR_WRC_MASK; > + } > kvmppc_set_tcr(vcpu, spr_val); > break; > > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index > 87f4dc8..63457cb 100644 > --- a/arch/powerpc/kvm/powerpc.c > +++ b/arch/powerpc/kvm/powerpc.c > @@ -220,6 +220,7 @@ int kvm_dev_ioctl_check_extension(long ext) > switch (ext) { > #ifdef CONFIG_BOOKE > case KVM_CAP_PPC_BOOKE_SREGS: > + case KVM_CAP_PPC_BOOKE_WATCHDOG: > #else > case KVM_CAP_PPC_SEGSTATE: > case KVM_CAP_PPC_HIOR: > @@ -386,13 +387,23 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) #ifdef > CONFIG_KVM_EXIT_TIMING > mutex_init(&vcpu->arch.exit_timing_lock); > #endif > - > +#ifdef CONFIG_BOOKE > + spin_lock_init(&vcpu->arch.wdt_lock); > + /* setup watchdog timer once */ > + setup_timer(&vcpu->arch.wdt_timer, kvmppc_watchdog_func, > + (unsigned long)vcpu); > +#endif > return 0; > } > > void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) { > kvmppc_mmu_destroy(vcpu); > +#ifdef CONFIG_BOOKE > + spin_lock(&vcpu->arch.wdt_lock); > + del_timer(&vcpu->arch.wdt_timer); > + spin_unlock(&vcpu->arch.wdt_lock); > +#endif > } > > void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) @@ -637,6 +648,12 @@ > static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, > r = 0; > vcpu->arch.papr_enabled = true; > break; > +#ifdef CONFIG_BOOKE > + case KVM_CAP_PPC_BOOKE_WATCHDOG: > + r = 0; > + vcpu->arch.watchdog_enabled = true; > + break; > +#endif > #if defined(CONFIG_KVM_E500V2) || defined(CONFIG_KVM_E500MC) > case KVM_CAP_SW_TLB: { > struct kvm_config_tlb cfg; > diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 2ce09aa..9ff5aa5 > 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -163,6 +163,7 @@ struct kvm_pit_config { > #define KVM_EXIT_OSI 18 > #define KVM_EXIT_PAPR_HCALL 19 > #define KVM_EXIT_S390_UCONTROL 20 > +#define KVM_EXIT_WATCHDOG 21 > > /* For KVM_EXIT_INTERNAL_ERROR */ > #define KVM_INTERNAL_ERROR_EMULATION 1 > @@ -618,6 +619,7 @@ struct kvm_ppc_smmu_info { #define > KVM_CAP_PPC_GET_SMMU_INFO 78 #define KVM_CAP_S390_COW 79 #define > KVM_CAP_PPC_ALLOC_HTAB 80 > +#define KVM_CAP_PPC_BOOKE_WATCHDOG 81 > > #ifdef KVM_CAP_IRQ_ROUTING > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index > 27ac8a4..41d32be 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -69,6 +69,7 @@ > #define KVM_REQ_IMMEDIATE_EXIT 15 > #define KVM_REQ_PMU 16 > #define KVM_REQ_PMI 17 > +#define KVM_REQ_WATCHDOG 18 > > #define KVM_USERSPACE_IRQ_SOURCE_ID 0 > > -- > 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 50ea12f..43cac48 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -467,6 +467,8 @@ struct kvm_vcpu_arch { ulong fault_esr; ulong queued_dear; ulong queued_esr; + spinlock_t wdt_lock; + struct timer_list wdt_timer; u32 tlbcfg[4]; u32 mmucfg; u32 epr; @@ -482,6 +484,7 @@ struct kvm_vcpu_arch { u8 osi_needed; u8 osi_enabled; u8 papr_enabled; + u8 watchdog_enabled; u8 sane; u8 cpu_type; u8 hcall_needed; diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 0124937..e5cf4b9 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -67,6 +67,7 @@ extern int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu); extern void kvmppc_emulate_dec(struct kvm_vcpu *vcpu); extern u32 kvmppc_get_dec(struct kvm_vcpu *vcpu, u64 tb); extern void kvmppc_decrementer_func(unsigned long data); +extern void kvmppc_watchdog_func(unsigned long data); extern int kvmppc_sanity_check(struct kvm_vcpu *vcpu); /* Core-specific hooks */ @@ -104,6 +105,8 @@ extern void kvmppc_core_queue_external(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq); extern void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq); +extern void kvmppc_core_queue_watchdog(struct kvm_vcpu *vcpu); +extern void kvmppc_core_dequeue_watchdog(struct kvm_vcpu *vcpu); extern int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned int op, int *advance); diff --git a/arch/powerpc/include/asm/reg_booke.h b/arch/powerpc/include/asm/reg_booke.h index 2d916c4..e07e6af 100644 --- a/arch/powerpc/include/asm/reg_booke.h +++ b/arch/powerpc/include/asm/reg_booke.h @@ -539,6 +539,13 @@ #define TCR_FIE 0x00800000 /* FIT Interrupt Enable */ #define TCR_ARE 0x00400000 /* Auto Reload Enable */ +#ifdef CONFIG_E500 +#define TCR_GET_WP(tcr) ((((tcr) & 0xC0000000) >> 30) | \ + (((tcr) & 0x1E0000) >> 15)) +#else +#define TCR_GET_WP(tcr) (((tcr) & 0xC0000000) >> 30) +#endif + /* Bit definitions for the TSR. */ #define TSR_ENW 0x80000000 /* Enable Next Watchdog */ #define TSR_WIS 0x40000000 /* WDT Interrupt Status */ diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index d25a097..71b4ce9 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -206,6 +206,16 @@ void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu, clear_bit(BOOKE_IRQPRIO_EXTERNAL_LEVEL, &vcpu->arch.pending_exceptions); } +void kvmppc_core_queue_watchdog(struct kvm_vcpu *vcpu) +{ + kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_WATCHDOG); +} + +void kvmppc_core_dequeue_watchdog(struct kvm_vcpu *vcpu) +{ + clear_bit(BOOKE_IRQPRIO_WATCHDOG, &vcpu->arch.pending_exceptions); +} + static void set_guest_srr(struct kvm_vcpu *vcpu, unsigned long srr0, u32 srr1) { #ifdef CONFIG_KVM_BOOKE_HV @@ -325,6 +335,7 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, msr_mask = MSR_CE | MSR_ME | MSR_DE; int_class = INT_CLASS_NONCRIT; break; + case BOOKE_IRQPRIO_WATCHDOG: case BOOKE_IRQPRIO_CRITICAL: case BOOKE_IRQPRIO_DBELL_CRIT: allowed = vcpu->arch.shared->msr & MSR_CE; @@ -404,12 +415,113 @@ static int kvmppc_booke_irqprio_deliver(struct kvm_vcpu *vcpu, return allowed; } +/* + * Return the number of jiffies until the next timeout. If the timeout is + * longer than the NEXT_TIMER_MAX_DELTA, then return NEXT_TIMER_MAX_DELTA + * because the larger value can break the timer APIs. + */ +static unsigned long watchdog_next_timeout(struct kvm_vcpu *vcpu) +{ + u64 tb, wdt_tb, wdt_ticks = 0; + u64 nr_jiffies = 0; + u32 period = TCR_GET_WP(vcpu->arch.tcr); + + wdt_tb = 1ULL << (63 - period); + tb = get_tb(); + /* + * The watchdog timeout will hapeen when TB bit corresponding + * to watchdog will toggle from 0 to 1. + */ + if (tb & wdt_tb) + wdt_ticks = wdt_tb; + + wdt_ticks += wdt_tb - (tb & (wdt_tb - 1)); + + /* Convert timebase ticks to jiffies */ + nr_jiffies = wdt_ticks; + + if (do_div(nr_jiffies, tb_ticks_per_jiffy)) + nr_jiffies++; + + return min_t(unsigned long long, nr_jiffies, NEXT_TIMER_MAX_DELTA); +} + +static void arm_next_watchdog(struct kvm_vcpu *vcpu) +{ + unsigned long nr_jiffies; + + spin_lock(&vcpu->arch.wdt_lock); + nr_jiffies = watchdog_next_timeout(vcpu); + /* + * If the number of jiffies of watchdog timer >= NEXT_TIMER_MAX_DELTA + * then do not run the watchdog timer as this can break timer APIs. + */ + if (nr_jiffies < NEXT_TIMER_MAX_DELTA) + mod_timer(&vcpu->arch.wdt_timer, jiffies + nr_jiffies); + else + del_timer(&vcpu->arch.wdt_timer); + spin_unlock(&vcpu->arch.wdt_lock); +} + +void kvmppc_watchdog_func(unsigned long data) +{ + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; + u32 tsr, new_tsr; + int final; + + do { + new_tsr = tsr = vcpu->arch.tsr; + final = 0; + + /* Time out event */ + if (tsr & TSR_ENW) { + if (tsr & TSR_WIS) + final = 1; + else + new_tsr = tsr | TSR_WIS; + } else { + new_tsr = tsr | TSR_ENW; + } + } while (cmpxchg(&vcpu->arch.tsr, tsr, new_tsr) != tsr); + + if (new_tsr & TSR_WIS) { + smp_wmb(); + kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); + kvm_vcpu_kick(vcpu); + } + + /* + * If this is final watchdog expiry and some action is required + * then exit to userspace. + */ + if (final && (vcpu->arch.tcr & TCR_WRC_MASK) && + vcpu->arch.watchdog_enabled) { + smp_wmb(); + kvm_make_request(KVM_REQ_WATCHDOG, vcpu); + kvm_vcpu_kick(vcpu); + } + + /* + * Stop running the watchdog timer after final expiration to + * prevent the host from being flooded with timers if the + * guest sets a short period. + * Timers will resume when TSR/TCR is updated next time. + */ + if (!final) + arm_next_watchdog(vcpu); +} + static void update_timer_ints(struct kvm_vcpu *vcpu) { if ((vcpu->arch.tcr & TCR_DIE) && (vcpu->arch.tsr & TSR_DIS)) kvmppc_core_queue_dec(vcpu); else kvmppc_core_dequeue_dec(vcpu); + + if ((vcpu->arch.tcr & TCR_WIE) && (vcpu->arch.tsr & TSR_WIS)) + kvmppc_core_queue_watchdog(vcpu); + else + kvmppc_core_dequeue_watchdog(vcpu); } static void kvmppc_core_check_exceptions(struct kvm_vcpu *vcpu) @@ -516,6 +628,13 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) goto out; } + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && + (vcpu->arch.tsr & (TSR_ENW | TSR_WIS))) { + kvm_run->exit_reason = KVM_EXIT_WATCHDOG; + ret = 0; + goto out; + } + kvm_guest_enter(); #ifdef CONFIG_PPC_FPU @@ -978,6 +1097,12 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, } } + if (kvm_check_request(KVM_REQ_WATCHDOG, vcpu) && + (vcpu->arch.tsr & (TSR_ENW | TSR_WIS))) { + run->exit_reason = KVM_EXIT_WATCHDOG; + r = RESUME_HOST | (r & RESUME_FLAG_NV); + } + return r; } @@ -1106,7 +1231,13 @@ static int set_sregs_base(struct kvm_vcpu *vcpu, } if (sregs->u.e.update_special & KVM_SREGS_E_UPDATE_TSR) { + u32 old_tsr = vcpu->arch.tsr; + vcpu->arch.tsr = sregs->u.e.tsr; + + if ((old_tsr ^ vcpu->arch.tsr) & (TSR_ENW | TSR_WIS)) + arm_next_watchdog(vcpu); + update_timer_ints(vcpu); } @@ -1267,6 +1398,7 @@ void kvmppc_core_commit_memory_region(struct kvm *kvm, void kvmppc_set_tcr(struct kvm_vcpu *vcpu, u32 new_tcr) { vcpu->arch.tcr = new_tcr; + arm_next_watchdog(vcpu); update_timer_ints(vcpu); } @@ -1281,6 +1413,14 @@ void kvmppc_set_tsr_bits(struct kvm_vcpu *vcpu, u32 tsr_bits) void kvmppc_clr_tsr_bits(struct kvm_vcpu *vcpu, u32 tsr_bits) { clear_bits(tsr_bits, &vcpu->arch.tsr); + + /* + * We may have stopped the watchdog due to + * being stuck on final expiration. + */ + if (tsr_bits & (TSR_ENW | TSR_WIS)) + arm_next_watchdog(vcpu); + update_timer_ints(vcpu); } diff --git a/arch/powerpc/kvm/booke_emulate.c b/arch/powerpc/kvm/booke_emulate.c index 12834bb..5a66ade 100644 --- a/arch/powerpc/kvm/booke_emulate.c +++ b/arch/powerpc/kvm/booke_emulate.c @@ -145,6 +145,14 @@ int kvmppc_booke_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val) kvmppc_clr_tsr_bits(vcpu, spr_val); break; case SPRN_TCR: + /* + * WRC is a 2-bit field that is supposed to preserve its + * value once written to non-zero. + */ + if (vcpu->arch.tcr & TCR_WRC_MASK) { + spr_val &= ~TCR_WRC_MASK; + spr_val |= vcpu->arch.tcr & TCR_WRC_MASK; + } kvmppc_set_tcr(vcpu, spr_val); break; diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 87f4dc8..63457cb 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -220,6 +220,7 @@ int kvm_dev_ioctl_check_extension(long ext) switch (ext) { #ifdef CONFIG_BOOKE case KVM_CAP_PPC_BOOKE_SREGS: + case KVM_CAP_PPC_BOOKE_WATCHDOG: #else case KVM_CAP_PPC_SEGSTATE: case KVM_CAP_PPC_HIOR: @@ -386,13 +387,23 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) #ifdef CONFIG_KVM_EXIT_TIMING mutex_init(&vcpu->arch.exit_timing_lock); #endif - +#ifdef CONFIG_BOOKE + spin_lock_init(&vcpu->arch.wdt_lock); + /* setup watchdog timer once */ + setup_timer(&vcpu->arch.wdt_timer, kvmppc_watchdog_func, + (unsigned long)vcpu); +#endif return 0; } void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) { kvmppc_mmu_destroy(vcpu); +#ifdef CONFIG_BOOKE + spin_lock(&vcpu->arch.wdt_lock); + del_timer(&vcpu->arch.wdt_timer); + spin_unlock(&vcpu->arch.wdt_lock); +#endif } void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) @@ -637,6 +648,12 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, r = 0; vcpu->arch.papr_enabled = true; break; +#ifdef CONFIG_BOOKE + case KVM_CAP_PPC_BOOKE_WATCHDOG: + r = 0; + vcpu->arch.watchdog_enabled = true; + break; +#endif #if defined(CONFIG_KVM_E500V2) || defined(CONFIG_KVM_E500MC) case KVM_CAP_SW_TLB: { struct kvm_config_tlb cfg; diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 2ce09aa..9ff5aa5 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -163,6 +163,7 @@ struct kvm_pit_config { #define KVM_EXIT_OSI 18 #define KVM_EXIT_PAPR_HCALL 19 #define KVM_EXIT_S390_UCONTROL 20 +#define KVM_EXIT_WATCHDOG 21 /* For KVM_EXIT_INTERNAL_ERROR */ #define KVM_INTERNAL_ERROR_EMULATION 1 @@ -618,6 +619,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_PPC_GET_SMMU_INFO 78 #define KVM_CAP_S390_COW 79 #define KVM_CAP_PPC_ALLOC_HTAB 80 +#define KVM_CAP_PPC_BOOKE_WATCHDOG 81 #ifdef KVM_CAP_IRQ_ROUTING diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 27ac8a4..41d32be 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -69,6 +69,7 @@ #define KVM_REQ_IMMEDIATE_EXIT 15 #define KVM_REQ_PMU 16 #define KVM_REQ_PMI 17 +#define KVM_REQ_WATCHDOG 18 #define KVM_USERSPACE_IRQ_SOURCE_ID 0