diff options
Diffstat (limited to 'arch/s390/kvm')
-rw-r--r-- | arch/s390/kvm/Makefile | 2 | ||||
-rw-r--r-- | arch/s390/kvm/gaccess.c | 239 | ||||
-rw-r--r-- | arch/s390/kvm/gaccess.h | 3 | ||||
-rw-r--r-- | arch/s390/kvm/interrupt.c | 5 | ||||
-rw-r--r-- | arch/s390/kvm/kvm-s390.c | 111 | ||||
-rw-r--r-- | arch/s390/kvm/kvm-s390.h | 10 | ||||
-rw-r--r-- | arch/s390/kvm/priv.c | 1 | ||||
-rw-r--r-- | arch/s390/kvm/sigp.c | 10 | ||||
-rw-r--r-- | arch/s390/kvm/vsie.c | 1091 |
9 files changed, 1443 insertions, 29 deletions
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile index 82e73e2b953d..09a9e6dfc09f 100644 --- a/arch/s390/kvm/Makefile +++ b/arch/s390/kvm/Makefile @@ -12,6 +12,6 @@ common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/async_pf.o $(KVM)/irqch ccflags-y := -Ivirt/kvm -Iarch/s390/kvm kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o -kvm-objs += diag.o gaccess.o guestdbg.o sthyi.o +kvm-objs += diag.o gaccess.o guestdbg.o sthyi.o vsie.o obj-$(CONFIG_KVM) += kvm.o diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 8e245e764c21..54200208bf24 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -8,6 +8,7 @@ #include <linux/vmalloc.h> #include <linux/err.h> #include <asm/pgtable.h> +#include <asm/gmap.h> #include "kvm-s390.h" #include "gaccess.h" #include <asm/switch_to.h> @@ -946,3 +947,241 @@ int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra) return 0; return trans_exc(vcpu, PGM_PROTECTION, gra, 0, GACC_STORE, PROT_TYPE_LA); } + +/** + * kvm_s390_shadow_tables - walk the guest page table and create shadow tables + * @sg: pointer to the shadow guest address space structure + * @saddr: faulting address in the shadow gmap + * @pgt: pointer to the page table address result + * @fake: pgt references contiguous guest memory block, not a pgtable + */ +static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, + unsigned long *pgt, int *dat_protection, + int *fake) +{ + struct gmap *parent; + union asce asce; + union vaddress vaddr; + unsigned long ptr; + int rc; + + *fake = 0; + *dat_protection = 0; + parent = sg->parent; + vaddr.addr = saddr; + asce.val = sg->orig_asce; + ptr = asce.origin * 4096; + if (asce.r) { + *fake = 1; + asce.dt = ASCE_TYPE_REGION1; + } + switch (asce.dt) { + case ASCE_TYPE_REGION1: + if (vaddr.rfx01 > asce.tl && !asce.r) + return PGM_REGION_FIRST_TRANS; + break; + case ASCE_TYPE_REGION2: + if (vaddr.rfx) + return PGM_ASCE_TYPE; + if (vaddr.rsx01 > asce.tl) + return PGM_REGION_SECOND_TRANS; + break; + case ASCE_TYPE_REGION3: + if (vaddr.rfx || vaddr.rsx) + return PGM_ASCE_TYPE; + if (vaddr.rtx01 > asce.tl) + return PGM_REGION_THIRD_TRANS; + break; + case ASCE_TYPE_SEGMENT: + if (vaddr.rfx || vaddr.rsx || vaddr.rtx) + return PGM_ASCE_TYPE; + if (vaddr.sx01 > asce.tl) + return PGM_SEGMENT_TRANSLATION; + break; + } + + switch (asce.dt) { + case ASCE_TYPE_REGION1: { + union region1_table_entry rfte; + + if (*fake) { + /* offset in 16EB guest memory block */ + ptr = ptr + ((unsigned long) vaddr.rsx << 53UL); + rfte.val = ptr; + goto shadow_r2t; + } + rc = gmap_read_table(parent, ptr + vaddr.rfx * 8, &rfte.val); + if (rc) + return rc; + if (rfte.i) + return PGM_REGION_FIRST_TRANS; + if (rfte.tt != TABLE_TYPE_REGION1) + return PGM_TRANSLATION_SPEC; + if (vaddr.rsx01 < rfte.tf || vaddr.rsx01 > rfte.tl) + return PGM_REGION_SECOND_TRANS; + if (sg->edat_level >= 1) + *dat_protection |= rfte.p; + ptr = rfte.rto << 12UL; +shadow_r2t: + rc = gmap_shadow_r2t(sg, saddr, rfte.val, *fake); + if (rc) + return rc; + /* fallthrough */ + } + case ASCE_TYPE_REGION2: { + union region2_table_entry rste; + + if (*fake) { + /* offset in 8PB guest memory block */ + ptr = ptr + ((unsigned long) vaddr.rtx << 42UL); + rste.val = ptr; + goto shadow_r3t; + } + rc = gmap_read_table(parent, ptr + vaddr.rsx * 8, &rste.val); + if (rc) + return rc; + if (rste.i) + return PGM_REGION_SECOND_TRANS; + if (rste.tt != TABLE_TYPE_REGION2) + return PGM_TRANSLATION_SPEC; + if (vaddr.rtx01 < rste.tf || vaddr.rtx01 > rste.tl) + return PGM_REGION_THIRD_TRANS; + if (sg->edat_level >= 1) + *dat_protection |= rste.p; + ptr = rste.rto << 12UL; +shadow_r3t: + rste.p |= *dat_protection; + rc = gmap_shadow_r3t(sg, saddr, rste.val, *fake); + if (rc) + return rc; + /* fallthrough */ + } + case ASCE_TYPE_REGION3: { + union region3_table_entry rtte; + + if (*fake) { + /* offset in 4TB guest memory block */ + ptr = ptr + ((unsigned long) vaddr.sx << 31UL); + rtte.val = ptr; + goto shadow_sgt; + } + rc = gmap_read_table(parent, ptr + vaddr.rtx * 8, &rtte.val); + if (rc) + return rc; + if (rtte.i) + return PGM_REGION_THIRD_TRANS; + if (rtte.tt != TABLE_TYPE_REGION3) + return PGM_TRANSLATION_SPEC; + if (rtte.cr && asce.p && sg->edat_level >= 2) + return PGM_TRANSLATION_SPEC; + if (rtte.fc && sg->edat_level >= 2) { + *dat_protection |= rtte.fc0.p; + *fake = 1; + ptr = rtte.fc1.rfaa << 31UL; + rtte.val = ptr; + goto shadow_sgt; + } + if (vaddr.sx01 < rtte.fc0.tf || vaddr.sx01 > rtte.fc0.tl) + return PGM_SEGMENT_TRANSLATION; + if (sg->edat_level >= 1) + *dat_protection |= rtte.fc0.p; + ptr = rtte.fc0.sto << 12UL; +shadow_sgt: + rtte.fc0.p |= *dat_protection; + rc = gmap_shadow_sgt(sg, saddr, rtte.val, *fake); + if (rc) + return rc; + /* fallthrough */ + } + case ASCE_TYPE_SEGMENT: { + union segment_table_entry ste; + + if (*fake) { + /* offset in 2G guest memory block */ + ptr = ptr + ((unsigned long) vaddr.sx << 20UL); + ste.val = ptr; + goto shadow_pgt; + } + rc = gmap_read_table(parent, ptr + vaddr.sx * 8, &ste.val); + if (rc) + return rc; + if (ste.i) + return PGM_SEGMENT_TRANSLATION; + if (ste.tt != TABLE_TYPE_SEGMENT) + return PGM_TRANSLATION_SPEC; + if (ste.cs && asce.p) + return PGM_TRANSLATION_SPEC; + *dat_protection |= ste.fc0.p; + if (ste.fc && sg->edat_level >= 1) { + *fake = 1; + ptr = ste.fc1.sfaa << 20UL; + ste.val = ptr; + goto shadow_pgt; + } + ptr = ste.fc0.pto << 11UL; +shadow_pgt: + ste.fc0.p |= *dat_protection; + rc = gmap_shadow_pgt(sg, saddr, ste.val, *fake); + if (rc) + return rc; + } + } + /* Return the parent address of the page table */ + *pgt = ptr; + return 0; +} + +/** + * kvm_s390_shadow_fault - handle fault on a shadow page table + * @vcpu: virtual cpu + * @sg: pointer to the shadow guest address space structure + * @saddr: faulting address in the shadow gmap + * + * Returns: - 0 if the shadow fault was successfully resolved + * - > 0 (pgm exception code) on exceptions while faulting + * - -EAGAIN if the caller can retry immediately + * - -EFAULT when accessing invalid guest addresses + * - -ENOMEM if out of memory + */ +int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg, + unsigned long saddr) +{ + union vaddress vaddr; + union page_table_entry pte; + unsigned long pgt; + int dat_protection, fake; + int rc; + + down_read(&sg->mm->mmap_sem); + /* + * We don't want any guest-2 tables to change - so the parent + * tables/pointers we read stay valid - unshadowing is however + * always possible - only guest_table_lock protects us. + */ + ipte_lock(vcpu); + + rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection, &fake); + if (rc) + rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection, + &fake); + + vaddr.addr = saddr; + if (fake) { + /* offset in 1MB guest memory block */ + pte.val = pgt + ((unsigned long) vaddr.px << 12UL); + goto shadow_page; + } + if (!rc) + rc = gmap_read_table(sg->parent, pgt + vaddr.px * 8, &pte.val); + if (!rc && pte.i) + rc = PGM_PAGE_TRANSLATION; + if (!rc && (pte.z || (pte.co && sg->edat_level < 1))) + rc = PGM_TRANSLATION_SPEC; +shadow_page: + pte.p |= dat_protection; + if (!rc) + rc = gmap_shadow_page(sg, saddr, __pte(pte.val)); + ipte_unlock(vcpu); + up_read(&sg->mm->mmap_sem); + return rc; +} diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h index df0a79dd8159..8756569ad938 100644 --- a/arch/s390/kvm/gaccess.h +++ b/arch/s390/kvm/gaccess.h @@ -361,4 +361,7 @@ void ipte_unlock(struct kvm_vcpu *vcpu); int ipte_lock_held(struct kvm_vcpu *vcpu); int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra); +int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *shadow, + unsigned long saddr); + #endif /* __KVM_S390_GACCESS_H */ diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index d72c4a877622..ca19627779db 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -995,6 +995,11 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) swake_up(&vcpu->wq); vcpu->stat.halt_wakeup++; } + /* + * The VCPU might not be sleeping but is executing the VSIE. Let's + * kick it, so it leaves the SIE to process the request. + */ + kvm_s390_vsie_kick(vcpu); } enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 0dcf9b8fc12c..03eeeb0ded24 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -21,6 +21,7 @@ #include <linux/init.h> #include <linux/kvm.h> #include <linux/kvm_host.h> +#include <linux/mman.h> #include <linux/module.h> #include <linux/random.h> #include <linux/slab.h> @@ -98,6 +99,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { "instruction_stfl", VCPU_STAT(instruction_stfl) }, { "instruction_tprot", VCPU_STAT(instruction_tprot) }, { "instruction_sthyi", VCPU_STAT(instruction_sthyi) }, + { "instruction_sie", VCPU_STAT(instruction_sie) }, { "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) }, { "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) }, { "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) }, @@ -123,6 +125,11 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { NULL } }; +/* allow nested virtualization in KVM (if enabled by user space) */ +static int nested; +module_param(nested, int, S_IRUGO); +MODULE_PARM_DESC(nested, "Nested virtualization support"); + /* upper facilities limit for kvm */ unsigned long kvm_s390_fac_list_mask[16] = { 0xffe6000000000000UL, @@ -141,6 +148,7 @@ static DECLARE_BITMAP(kvm_s390_available_cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS) static struct kvm_s390_vm_cpu_subfunc kvm_s390_available_subfunc; static struct gmap_notifier gmap_notifier; +static struct gmap_notifier vsie_gmap_notifier; debug_info_t *kvm_s390_dbf; /* Section: not file related */ @@ -150,7 +158,8 @@ int kvm_arch_hardware_enable(void) return 0; } -static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address); +static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start, + unsigned long end); /* * This callback is executed during stop_machine(). All CPUs are therefore @@ -172,6 +181,8 @@ static int kvm_clock_sync(struct notifier_block *notifier, unsigned long val, vcpu->arch.sie_block->epoch -= *delta; if (vcpu->arch.cputm_enabled) vcpu->arch.cputm_start += *delta; + if (vcpu->arch.vsie_block) + vcpu->arch.vsie_block->epoch -= *delta; } } return NOTIFY_OK; @@ -184,7 +195,9 @@ static struct notifier_block kvm_clock_notifier = { int kvm_arch_hardware_setup(void) { gmap_notifier.notifier_call = kvm_gmap_notifier; - gmap_register_ipte_notifier(&gmap_notifier); + gmap_register_pte_notifier(&gmap_notifier); + vsie_gmap_notifier.notifier_call = kvm_s390_vsie_gmap_notifier; + gmap_register_pte_notifier(&vsie_gmap_notifier); atomic_notifier_chain_register(&s390_epoch_delta_notifier, &kvm_clock_notifier); return 0; @@ -192,7 +205,8 @@ int kvm_arch_hardware_setup(void) void kvm_arch_hardware_unsetup(void) { - gmap_unregister_ipte_notifier(&gmap_notifier); + gmap_unregister_pte_notifier(&gmap_notifier); + gmap_unregister_pte_notifier(&vsie_gmap_notifier); atomic_notifier_chain_unregister(&s390_epoch_delta_notifier, &kvm_clock_notifier); } @@ -250,6 +264,46 @@ static void kvm_s390_cpu_feat_init(void) if (MACHINE_HAS_ESOP) allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); + /* + * We need SIE support, ESOP (PROT_READ protection for gmap_shadow), + * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing). + */ + if (!sclp.has_sief2 || !MACHINE_HAS_ESOP || !sclp.has_64bscao || + !test_facility(3) || !nested) + return; + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2); + if (sclp.has_64bscao) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_64BSCAO); + if (sclp.has_siif) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIIF); + if (sclp.has_gpere) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GPERE); + if (sclp.has_gsls) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GSLS); + if (sclp.has_ib) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB); + if (sclp.has_cei) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI); + if (sclp.has_ibs) + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS); + /* + * KVM_S390_VM_CPU_FEAT_SKEY: Wrong shadow of PTE.I bits will make + * all skey handling functions read/set the skey from the PGSTE + * instead of the real storage key. + * + * KVM_S390_VM_CPU_FEAT_CMMA: Wrong shadow of PTE.I bits will make + * pages being detected as preserved although they are resident. + * + * KVM_S390_VM_CPU_FEAT_PFMFI: Wrong shadow of PTE.I bits will + * have the same effect as for KVM_S390_VM_CPU_FEAT_SKEY. + * + * For KVM_S390_VM_CPU_FEAT_SKEY, KVM_S390_VM_CPU_FEAT_CMMA and + * KVM_S390_VM_CPU_FEAT_PFMFI, all PTE.I and PGSTE bits have to be + * correctly shadowed. We can do that for the PGSTE but not for PTE.I. + * + * KVM_S390_VM_CPU_FEAT_SIGPIF: Wrong SCB addresses in the SCA. We + * cannot easily shadow the SCA because of the ipte lock. + */ } int kvm_arch_init(void *opaque) @@ -530,20 +584,20 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att if (!new_limit) return -EINVAL; - /* gmap_alloc takes last usable address */ + /* gmap_create takes last usable address */ if (new_limit != KVM_S390_NO_MEM_LIMIT) new_limit -= 1; ret = -EBUSY; mutex_lock(&kvm->lock); if (!kvm->created_vcpus) { - /* gmap_alloc will round the limit up */ - struct gmap *new = gmap_alloc(current->mm, new_limit); + /* gmap_create will round the limit up */ + struct gmap *new = gmap_create(current->mm, new_limit); if (!new) { ret = -ENOMEM; } else { - gmap_free(kvm->arch.gmap); + gmap_remove(kvm->arch.gmap); new->private = kvm; kvm->arch.gmap = new; ret = 0; @@ -1392,7 +1446,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) else kvm->arch.mem_limit = min_t(unsigned long, TASK_MAX_SIZE, sclp.hamax + 1); - kvm->arch.gmap = gmap_alloc(current->mm, kvm->arch.mem_limit - 1); + kvm->arch.gmap = gmap_create(current->mm, kvm->arch.mem_limit - 1); if (!kvm->arch.gmap) goto out_err; kvm->arch.gmap->private = kvm; @@ -1404,6 +1458,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) kvm->arch.epoch = 0; spin_lock_init(&kvm->arch.start_stop_lock); + kvm_s390_vsie_init(kvm); KVM_EVENT(3, "vm 0x%pK created by pid %u", kvm, current->pid); return 0; @@ -1425,7 +1480,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) sca_del_vcpu(vcpu); if (kvm_is_ucontrol(vcpu->kvm)) - gmap_free(vcpu->arch.gmap); + gmap_remove(vcpu->arch.gmap); if (vcpu->kvm->arch.use_cmma) kvm_s390_vcpu_unsetup_cmma(vcpu); @@ -1458,16 +1513,17 @@ void kvm_arch_destroy_vm(struct kvm *kvm) debug_unregister(kvm->arch.dbf); free_page((unsigned long)kvm->arch.sie_page2); if (!kvm_is_ucontrol(kvm)) - gmap_free(kvm->arch.gmap); + gmap_remove(kvm->arch.gmap); kvm_s390_destroy_adapters(kvm); kvm_s390_clear_float_irqs(kvm); + kvm_s390_vsie_destroy(kvm); KVM_EVENT(3, "vm 0x%pK destroyed", kvm); } /* Section: vcpu related */ static int __kvm_ucontrol_vcpu_init(struct kvm_vcpu *vcpu) { - vcpu->arch.gmap = gmap_alloc(current->mm, -1UL); + vcpu->arch.gmap = gmap_create(current->mm, -1UL); if (!vcpu->arch.gmap) return -ENOMEM; vcpu->arch.gmap->private = vcpu->kvm; @@ -1717,7 +1773,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) save_access_regs(vcpu->arch.host_acrs); restore_access_regs(vcpu->run->s.regs.acrs); - gmap_enable(vcpu->arch.gmap); + gmap_enable(vcpu->arch.enabled_gmap); atomic_or(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu)) __start_cpu_timer_accounting(vcpu); @@ -1730,7 +1786,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu)) __stop_cpu_timer_accounting(vcpu); atomic_andnot(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); - gmap_disable(vcpu->arch.gmap); + vcpu->arch.enabled_gmap = gmap_get_enabled(); + gmap_disable(vcpu->arch.enabled_gmap); /* Save guest register state */ save_fpu_regs(); @@ -1779,7 +1836,8 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) vcpu->arch.gmap = vcpu->kvm->arch.gmap; sca_add_vcpu(vcpu); } - + /* make vcpu_load load the right gmap on the first trigger */ + vcpu->arch.enabled_gmap = vcpu->arch.gmap; } static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu) @@ -1976,16 +2034,25 @@ void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu) kvm_s390_vcpu_request(vcpu); } -static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address) +static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start, + unsigned long end) { - int i; struct kvm *kvm = gmap->private; struct kvm_vcpu *vcpu; + unsigned long prefix; + int i; + if (gmap_is_shadow(gmap)) + return; + if (start >= 1UL << 31) + /* We are only interested in prefix pages */ + return; kvm_for_each_vcpu(i, vcpu, kvm) { /* match against both prefix pages */ - if (kvm_s390_get_prefix(vcpu) == (address & ~0x1000UL)) { - VCPU_EVENT(vcpu, 2, "gmap notifier for %lx", address); + prefix = kvm_s390_get_prefix(vcpu); + if (prefix <= end && start <= prefix + 2*PAGE_SIZE - 1) { + VCPU_EVENT(vcpu, 2, "gmap notifier for %lx-%lx", + start, end); kvm_s390_sync_request(KVM_REQ_MMU_RELOAD, vcpu); } } @@ -2264,16 +2331,16 @@ retry: return 0; /* * We use MMU_RELOAD just to re-arm the ipte notifier for the - * guest prefix page. gmap_ipte_notify will wait on the ptl lock. + * guest prefix page. gmap_mprotect_notify will wait on the ptl lock. * This ensures that the ipte instruction for this request has * already finished. We might race against a second unmapper that * wants to set the blocking bit. Lets just retry the request loop. */ if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) { int rc; - rc = gmap_ipte_notify(vcpu->arch.gmap, - kvm_s390_get_prefix(vcpu), - PAGE_SIZE * 2); + rc = gmap_mprotect_notify(vcpu->arch.gmap, + kvm_s390_get_prefix(vcpu), + PAGE_SIZE * 2, PROT_WRITE); if (rc) return rc; goto retry; diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index 52aa47e112d8..031f451bb2cf 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -56,7 +56,7 @@ static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu) static inline int is_vcpu_idle(struct kvm_vcpu *vcpu) { - return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_WAIT; + return test_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask); } static inline int kvm_is_ucontrol(struct kvm *kvm) @@ -252,6 +252,14 @@ int kvm_s390_handle_stctl(struct kvm_vcpu *vcpu); int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu); int kvm_s390_handle_eb(struct kvm_vcpu *vcpu); +/* implemented in vsie.c */ +int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu); +void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu); +void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start, + unsigned long end); +void kvm_s390_vsie_init(struct kvm *kvm); +void kvm_s390_vsie_destroy(struct kvm *kvm); + /* implemented in sigp.c */ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu); int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu); diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 3db3be139992..c77ad2dc334f 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -719,6 +719,7 @@ static const intercept_handler_t b2_handlers[256] = { [0x10] = handle_set_prefix, [0x11] = handle_store_prefix, [0x12] = handle_store_cpu_address, + [0x14] = kvm_s390_handle_vsie, [0x21] = handle_ipte_interlock, [0x29] = handle_iske, [0x2a] = handle_rrbe, diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c index 28ea0cab1f1b..1a252f537081 100644 --- a/arch/s390/kvm/sigp.c +++ b/arch/s390/kvm/sigp.c @@ -77,18 +77,18 @@ static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT; u16 p_asn, s_asn; psw_t *psw; - u32 flags; + bool idle; - flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags); + idle = is_vcpu_idle(vcpu); psw = &dst_vcpu->arch.sie_block->gpsw; p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */ s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */ /* Inject the emergency signal? */ - if (!(flags & CPUSTAT_STOPPED) + if (!is_vcpu_stopped(vcpu) || (psw->mask & psw_int_mask) != psw_int_mask - || ((flags & CPUSTAT_WAIT) && psw->addr != 0) - || (!(flags & CPUSTAT_WAIT) && (asn == p_asn || asn == s_asn))) { + || (idle && psw->addr != 0) + || (!idle && (asn == p_asn || asn == s_asn))) { return __inject_sigp_emergency(vcpu, dst_vcpu); } else { *reg &= 0xffffffff00000000UL; diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c new file mode 100644 index 000000000000..6895e7b3be12 --- /dev/null +++ b/arch/s390/kvm/vsie.c @@ -0,0 +1,1091 @@ +/* + * kvm nested virtualization support for s390x + * + * Copyright IBM Corp. 2016 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2 only) + * as published by the Free Software Foundation. + * + * Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com> + */ +#include <linux/vmalloc.h> +#include <linux/kvm_host.h> +#include <linux/bug.h> +#include <linux/list.h> +#include <linux/bitmap.h> +#include <asm/gmap.h> +#include <asm/mmu_context.h> +#include <asm/sclp.h> +#include <asm/nmi.h> +#include <asm/dis.h> +#include "kvm-s390.h" +#include "gaccess.h" + +struct vsie_page { + struct kvm_s390_sie_block scb_s; /* 0x0000 */ + /* the pinned originial scb */ + struct kvm_s390_sie_block *scb_o; /* 0x0200 */ + /* the shadow gmap in use by the vsie_page */ + struct gmap *gmap; /* 0x0208 */ + /* address of the last reported fault to guest2 */ + unsigned long fault_addr; /* 0x0210 */ + __u8 reserved[0x0700 - 0x0218]; /* 0x0218 */ + struct kvm_s390_crypto_cb crycb; /* 0x0700 */ + __u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */ +} __packed; + +/* trigger a validity icpt for the given scb */ +static int set_validity_icpt(struct kvm_s390_sie_block *scb, + __u16 reason_code) +{ + scb->ipa = 0x1000; + scb->ipb = ((__u32) reason_code) << 16; + scb->icptcode = ICPT_VALIDITY; + return 1; +} + +/* mark the prefix as unmapped, this will block the VSIE */ +static void prefix_unmapped(struct vsie_page *vsie_page) +{ + atomic_or(PROG_REQUEST, &vsie_page->scb_s.prog20); +} + +/* mark the prefix as unmapped and wait until the VSIE has been left */ +static void prefix_unmapped_sync(struct vsie_page *vsie_page) +{ + prefix_unmapped(vsie_page); + if (vsie_page->scb_s.prog0c & PROG_IN_SIE) + atomic_or(CPUSTAT_STOP_INT, &vsie_page->scb_s.cpuflags); + while (vsie_page->scb_s.prog0c & PROG_IN_SIE) + cpu_relax(); +} + +/* mark the prefix as mapped, this will allow the VSIE to run */ +static void prefix_mapped(struct vsie_page *vsie_page) +{ + atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20); +} + +/* test if the prefix is mapped into the gmap shadow */ +static int prefix_is_mapped(struct vsie_page *vsie_page) +{ + return !(atomic_read(&vsie_page->scb_s.prog20) & PROG_REQUEST); +} + +/* copy the updated intervention request bits into the shadow scb */ +static void update_intervention_requests(struct vsie_page *vsie_page) +{ + const int bits = CPUSTAT_STOP_INT | CPUSTAT_IO_INT | CPUSTAT_EXT_INT; + int cpuflags; + + cpuflags = atomic_read(&vsie_page->scb_o->cpuflags); + atomic_andnot(bits, &vsie_page->scb_s.cpuflags); + atomic_or(cpuflags & bits, &vsie_page->scb_s.cpuflags); +} + +/* shadow (filter and validate) the cpuflags */ +static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + int newflags, cpuflags = atomic_read(&scb_o->cpuflags); + + /* we don't allow ESA/390 guests */ + if (!(cpuflags & CPUSTAT_ZARCH)) + return set_validity_icpt(scb_s, 0x0001U); + + if (cpuflags & (CPUSTAT_RRF | CPUSTAT_MCDS)) + return set_validity_icpt(scb_s, 0x0001U); + else if (cpuflags & (CPUSTAT_SLSV | CPUSTAT_SLSR)) + return set_validity_icpt(scb_s, 0x0007U); + + /* intervention requests will be set later */ + newflags = CPUSTAT_ZARCH; + if (cpuflags & CPUSTAT_GED && test_kvm_facility(vcpu->kvm, 8)) + newflags |= CPUSTAT_GED; + if (cpuflags & CPUSTAT_GED2 && test_kvm_facility(vcpu->kvm, 78)) { + if (cpuflags & CPUSTAT_GED) + return set_validity_icpt(scb_s, 0x0001U); + newflags |= CPUSTAT_GED2; + } + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GPERE)) + newflags |= cpuflags & CPUSTAT_P; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS)) + newflags |= cpuflags & CPUSTAT_SM; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS)) + newflags |= cpuflags & CPUSTAT_IBS; + + atomic_set(&scb_s->cpuflags, newflags); + return 0; +} + +/* + * Create a shadow copy of the crycb block and setup key wrapping, if + * requested for guest 3 and enabled for guest 2. + * + * We only accept format-1 (no AP in g2), but convert it into format-2 + * There is nothing to do for format-0. + * + * Returns: - 0 if shadowed or nothing to do + * - > 0 if control has to be given to guest 2 + */ +static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + u32 crycb_addr = scb_o->crycbd & 0x7ffffff8U; + unsigned long *b1, *b2; + u8 ecb3_flags; + + scb_s->crycbd = 0; + if (!(scb_o->crycbd & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1)) + return 0; + /* format-1 is supported with message-security-assist extension 3 */ + if (!test_kvm_facility(vcpu->kvm, 76)) + return 0; + /* we may only allow it if enabled for guest 2 */ + ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 & + (ECB3_AES | ECB3_DEA); + if (!ecb3_flags) + return 0; + + if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK)) + return set_validity_icpt(scb_s, 0x003CU); + else if (!crycb_addr) + return set_validity_icpt(scb_s, 0x0039U); + + /* copy only the wrapping keys */ + if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56)) + return set_validity_icpt(scb_s, 0x0035U); + + scb_s->ecb3 |= ecb3_flags; + scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT1 | + CRYCB_FORMAT2; + + /* xor both blocks in one run */ + b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask; + b2 = (unsigned long *) + vcpu->kvm->arch.crypto.crycb->dea_wrapping_key_mask; + /* as 56%8 == 0, bitmap_xor won't overwrite any data */ + bitmap_xor(b1, b1, b2, BITS_PER_BYTE * 56); + return 0; +} + +/* shadow (round up/down) the ibc to avoid validity icpt */ +static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + __u64 min_ibc = (sclp.ibc >> 16) & 0x0fffU; + + scb_s->ibc = 0; + /* ibc installed in g2 and requested for g3 */ + if (vcpu->kvm->arch.model.ibc && (scb_o->ibc & 0x0fffU)) { + scb_s->ibc = scb_o->ibc & 0x0fffU; + /* takte care of the minimum ibc level of the machine */ + if (scb_s->ibc < min_ibc) + scb_s->ibc = min_ibc; + /* take care of the maximum ibc level set for the guest */ + if (scb_s->ibc > vcpu->kvm->arch.model.ibc) + scb_s->ibc = vcpu->kvm->arch.model.ibc; + } +} + +/* unshadow the scb, copying parameters back to the real scb */ +static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + + /* interception */ + scb_o->icptcode = scb_s->icptcode; + scb_o->icptstatus = scb_s->icptstatus; + scb_o->ipa = scb_s->ipa; + scb_o->ipb = scb_s->ipb; + scb_o->gbea = scb_s->gbea; + + /* timer */ + scb_o->cputm = scb_s->cputm; + scb_o->ckc = scb_s->ckc; + scb_o->todpr = scb_s->todpr; + + /* guest state */ + scb_o->gpsw = scb_s->gpsw; + scb_o->gg14 = scb_s->gg14; + scb_o->gg15 = scb_s->gg15; + memcpy(scb_o->gcr, scb_s->gcr, 128); + scb_o->pp = scb_s->pp; + + /* interrupt intercept */ + switch (scb_s->icptcode) { + case ICPT_PROGI: + case ICPT_INSTPROGI: + case ICPT_EXTINT: + memcpy((void *)((u64)scb_o + 0xc0), + (void *)((u64)scb_s + 0xc0), 0xf0 - 0xc0); + break; + case ICPT_PARTEXEC: + /* MVPG only */ + memcpy((void *)((u64)scb_o + 0xc0), + (void *)((u64)scb_s + 0xc0), 0xd0 - 0xc0); + break; + } + + if (scb_s->ihcpu != 0xffffU) + scb_o->ihcpu = scb_s->ihcpu; +} + +/* + * Setup the shadow scb by copying and checking the relevant parts of the g2 + * provided scb. + * + * Returns: - 0 if the scb has been shadowed + * - > 0 if control has to be given to guest 2 + */ +static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + bool had_tx = scb_s->ecb & 0x10U; + unsigned long new_mso = 0; + int rc; + + /* make sure we don't have any leftovers when reusing the scb */ + scb_s->icptcode = 0; + scb_s->eca = 0; + scb_s->ecb = 0; + scb_s->ecb2 = 0; + scb_s->ecb3 = 0; + scb_s->ecd = 0; + scb_s->fac = 0; + + rc = prepare_cpuflags(vcpu, vsie_page); + if (rc) + goto out; + + /* timer */ + scb_s->cputm = scb_o->cputm; + scb_s->ckc = scb_o->ckc; + scb_s->todpr = scb_o->todpr; + scb_s->epoch = scb_o->epoch; + + /* guest state */ + scb_s->gpsw = scb_o->gpsw; + scb_s->gg14 = scb_o->gg14; + scb_s->gg15 = scb_o->gg15; + memcpy(scb_s->gcr, scb_o->gcr, 128); + scb_s->pp = scb_o->pp; + + /* interception / execution handling */ + scb_s->gbea = scb_o->gbea; + scb_s->lctl = scb_o->lctl; + scb_s->svcc = scb_o->svcc; + scb_s->ictl = scb_o->ictl; + /* + * SKEY handling functions can't deal with false setting of PTE invalid + * bits. Therefore we cannot provide interpretation and would later + * have to provide own emulation handlers. + */ + scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE; + scb_s->icpua = scb_o->icpua; + + if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM)) + new_mso = scb_o->mso & 0xfffffffffff00000UL; + /* if the hva of the prefix changes, we have to remap the prefix */ + if (scb_s->mso != new_mso || scb_s->prefix != scb_o->prefix) + prefix_unmapped(vsie_page); + /* SIE will do mso/msl validity and exception checks for us */ + scb_s->msl = scb_o->msl & 0xfffffffffff00000UL; + scb_s->mso = new_mso; + scb_s->prefix = scb_o->prefix; + + /* We have to definetly flush the tlb if this scb never ran */ + if (scb_s->ihcpu != 0xffffU) + scb_s->ihcpu = scb_o->ihcpu; + + /* MVPG and Protection Exception Interpretation are always available */ + scb_s->eca |= scb_o->eca & 0x01002000U; + /* Host-protection-interruption introduced with ESOP */ + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_ESOP)) + scb_s->ecb |= scb_o->ecb & 0x02U; + /* transactional execution */ + if (test_kvm_facility(vcpu->kvm, 73)) { + /* remap the prefix is tx is toggled on */ + if ((scb_o->ecb & 0x10U) && !had_tx) + prefix_unmapped(vsie_page); + scb_s->ecb |= scb_o->ecb & 0x10U; + } + /* SIMD */ + if (test_kvm_facility(vcpu->kvm, 129)) { + scb_s->eca |= scb_o->eca & 0x00020000U; + scb_s->ecd |= scb_o->ecd & 0x20000000U; + } + /* Run-time-Instrumentation */ + if (test_kvm_facility(vcpu->kvm, 64)) + scb_s->ecb3 |= scb_o->ecb3 & 0x01U; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIIF)) + scb_s->eca |= scb_o->eca & 0x00000001U; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IB)) + scb_s->eca |= scb_o->eca & 0x40000000U; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI)) + scb_s->eca |= scb_o->eca & 0x80000000U; + + prepare_ibc(vcpu, vsie_page); + rc = shadow_crycb(vcpu, vsie_page); +out: + if (rc) + unshadow_scb(vcpu, vsie_page); + return rc; +} + +void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start, + unsigned long end) +{ + struct kvm *kvm = gmap->private; + struct vsie_page *cur; + unsigned long prefix; + struct page *page; + int i; + + if (!gmap_is_shadow(gmap)) + return; + if (start >= 1UL << 31) + /* We are only interested in prefix pages */ + return; + + /* + * Only new shadow blocks are added to the list during runtime, + * therefore we can safely reference them all the time. + */ + for (i = 0; i < kvm->arch.vsie.page_count; i++) { + page = READ_ONCE(kvm->arch.vsie.pages[i]); + if (!page) + continue; + cur = page_to_virt(page); + if (READ_ONCE(cur->gmap) != gmap) + continue; + prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT; + /* with mso/msl, the prefix lies at an offset */ + prefix += cur->scb_s.mso; + if (prefix <= end && start <= prefix + 2 * PAGE_SIZE - 1) + prefix_unmapped_sync(cur); + } +} + +/* + * Map the first prefix page and if tx is enabled also the second prefix page. + * + * The prefix will be protected, a gmap notifier will inform about unmaps. + * The shadow scb must not be executed until the prefix is remapped, this is + * guaranteed by properly handling PROG_REQUEST. + * + * Returns: - 0 on if successfully mapped or already mapped + * - > 0 if control has to be given to guest 2 + * - -EAGAIN if the caller can retry immediately + * - -ENOMEM if out of memory + */ +static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT; + int rc; + + if (prefix_is_mapped(vsie_page)) + return 0; + + /* mark it as mapped so we can catch any concurrent unmappers */ + prefix_mapped(vsie_page); + + /* with mso/msl, the prefix lies at offset *mso* */ + prefix += scb_s->mso; + + rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix); + if (!rc && (scb_s->ecb & 0x10U)) + rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, + prefix + PAGE_SIZE); + /* + * We don't have to mprotect, we will be called for all unshadows. + * SIE will detect if protection applies and trigger a validity. + */ + if (rc) + prefix_unmapped(vsie_page); + if (rc > 0 || rc == -EFAULT) + rc = set_validity_icpt(scb_s, 0x0037U); + return rc; +} + +/* + * Pin the guest page given by gpa and set hpa to the pinned host address. + * Will always be pinned writable. + * + * Returns: - 0 on success + * - -EINVAL if the gpa is not valid guest storage + * - -ENOMEM if out of memory + */ +static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa) +{ + struct page *page; + hva_t hva; + int rc; + + hva = gfn_to_hva(kvm, gpa_to_gfn(gpa)); + if (kvm_is_error_hva(hva)) + return -EINVAL; + rc = get_user_pages_fast(hva, 1, 1, &page); + if (rc < 0) + return rc; + else if (rc != 1) + return -ENOMEM; + *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK); + return 0; +} + +/* Unpins a page previously pinned via pin_guest_page, marking it as dirty. */ +static void unpin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t hpa) +{ + struct page *page; + + page = virt_to_page(hpa); + set_page_dirty_lock(page); + put_page(page); + /* mark the page always as dirty for migration */ + mark_page_dirty(kvm, gpa_to_gfn(gpa)); +} + +/* unpin all blocks previously pinned by pin_blocks(), marking them dirty */ +static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + hpa_t hpa; + gpa_t gpa; + + hpa = (u64) scb_s->scaoh << 32 | scb_s->scaol; + if (hpa) { + gpa = scb_o->scaol & ~0xfUL; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO)) + gpa |= (u64) scb_o->scaoh << 32; + unpin_guest_page(vcpu->kvm, gpa, hpa); + scb_s->scaol = 0; + scb_s->scaoh = 0; + } + + hpa = scb_s->itdba; + if (hpa) { + gpa = scb_o->itdba & ~0xffUL; + unpin_guest_page(vcpu->kvm, gpa, hpa); + scb_s->itdba = 0; + } + + hpa = scb_s->gvrd; + if (hpa) { + gpa = scb_o->gvrd & ~0x1ffUL; + unpin_guest_page(vcpu->kvm, gpa, hpa); + scb_s->gvrd = 0; + } + + hpa = scb_s->riccbd; + if (hpa) { + gpa = scb_o->riccbd & ~0x3fUL; + unpin_guest_page(vcpu->kvm, gpa, hpa); + scb_s->riccbd = 0; + } +} + +/* + * Instead of shadowing some blocks, we can simply forward them because the + * addresses in the scb are 64 bit long. + * + * This works as long as the data lies in one page. If blocks ever exceed one + * page, we have to fall back to shadowing. + * + * As we reuse the sca, the vcpu pointers contained in it are invalid. We must + * therefore not enable any facilities that access these pointers (e.g. SIGPIF). + * + * Returns: - 0 if all blocks were pinned. + * - > 0 if control has to be given to guest 2 + * - -ENOMEM if out of memory + */ +static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + hpa_t hpa; + gpa_t gpa; + int rc = 0; + + gpa = scb_o->scaol & ~0xfUL; + if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO)) + gpa |= (u64) scb_o->scaoh << 32; + if (gpa) { + if (!(gpa & ~0x1fffUL)) + rc = set_validity_icpt(scb_s, 0x0038U); + else if ((gpa & ~0x1fffUL) == kvm_s390_get_prefix(vcpu)) + rc = set_validity_icpt(scb_s, 0x0011U); + else if ((gpa & PAGE_MASK) != + ((gpa + sizeof(struct bsca_block) - 1) & PAGE_MASK)) + rc = set_validity_icpt(scb_s, 0x003bU); + if (!rc) { + rc = pin_guest_page(vcpu->kvm, gpa, &hpa); + if (rc == -EINVAL) + rc = set_validity_icpt(scb_s, 0x0034U); + } + if (rc) + goto unpin; + scb_s->scaoh = (u32)((u64)hpa >> 32); + scb_s->scaol = (u32)(u64)hpa; + } + + gpa = scb_o->itdba & ~0xffUL; + if (gpa && (scb_s->ecb & 0x10U)) { + if (!(gpa & ~0x1fffU)) { + rc = set_validity_icpt(scb_s, 0x0080U); + goto unpin; + } + /* 256 bytes cannot cross page boundaries */ + rc = pin_guest_page(vcpu->kvm, gpa, &hpa); + if (rc == -EINVAL) + rc = set_validity_icpt(scb_s, 0x0080U); + if (rc) + goto unpin; + scb_s->itdba = hpa; + } + + gpa = scb_o->gvrd & ~0x1ffUL; + if (gpa && (scb_s->eca & 0x00020000U) && + !(scb_s->ecd & 0x20000000U)) { + if (!(gpa & ~0x1fffUL)) { + rc = set_validity_icpt(scb_s, 0x1310U); + goto unpin; + } + /* + * 512 bytes vector registers cannot cross page boundaries + * if this block gets bigger, we have to shadow it. + */ + rc = pin_guest_page(vcpu->kvm, gpa, &hpa); + if (rc == -EINVAL) + rc = set_validity_icpt(scb_s, 0x1310U); + if (rc) + goto unpin; + scb_s->gvrd = hpa; + } + + gpa = scb_o->riccbd & ~0x3fUL; + if (gpa && (scb_s->ecb3 & 0x01U)) { + if (!(gpa & ~0x1fffUL)) { + rc = set_validity_icpt(scb_s, 0x0043U); + goto unpin; + } + /* 64 bytes cannot cross page boundaries */ + rc = pin_guest_page(vcpu->kvm, gpa, &hpa); + if (rc == -EINVAL) + rc = set_validity_icpt(scb_s, 0x0043U); + /* Validity 0x0044 will be checked by SIE */ + if (rc) + goto unpin; + scb_s->gvrd = hpa; + } + return 0; +unpin: + unpin_blocks(vcpu, vsie_page); + return rc; +} + +/* unpin the scb provided by guest 2, marking it as dirty */ +static void unpin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, + gpa_t gpa) +{ + hpa_t hpa = (hpa_t) vsie_page->scb_o; + + if (hpa) + unpin_guest_page(vcpu->kvm, gpa, hpa); + vsie_page->scb_o = NULL; +} + +/* + * Pin the scb at gpa provided by guest 2 at vsie_page->scb_o. + * + * Returns: - 0 if the scb was pinned. + * - > 0 if control has to be given to guest 2 + * - -ENOMEM if out of memory + */ +static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, + gpa_t gpa) +{ + hpa_t hpa; + int rc; + + rc = pin_guest_page(vcpu->kvm, gpa, &hpa); + if (rc == -EINVAL) { + rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); + if (!rc) + rc = 1; + } + if (!rc) + vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa; + return rc; +} + +/* + * Inject a fault into guest 2. + * + * Returns: - > 0 if control has to be given to guest 2 + * < 0 if an error occurred during injection. + */ +static int inject_fault(struct kvm_vcpu *vcpu, __u16 code, __u64 vaddr, + bool write_flag) +{ + struct kvm_s390_pgm_info pgm = { + .code = code, + .trans_exc_code = + /* 0-51: virtual address */ + (vaddr & 0xfffffffffffff000UL) | + /* 52-53: store / fetch */ + (((unsigned int) !write_flag) + 1) << 10, + /* 62-63: asce id (alway primary == 0) */ + .exc_access_id = 0, /* always primary */ + .op_access_id = 0, /* not MVPG */ + }; + int rc; + + if (code == PGM_PROTECTION) + pgm.trans_exc_code |= 0x4UL; + + rc = kvm_s390_inject_prog_irq(vcpu, &pgm); + return rc ? rc : 1; +} + +/* + * Handle a fault during vsie execution on a gmap shadow. + * + * Returns: - 0 if the fault was resolved + * - > 0 if control has to be given to guest 2 + * - < 0 if an error occurred + */ +static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + int rc; + + if (current->thread.gmap_int_code == PGM_PROTECTION) + /* we can directly forward all protection exceptions */ + return inject_fault(vcpu, PGM_PROTECTION, + current->thread.gmap_addr, 1); + + rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, + current->thread.gmap_addr); + if (rc > 0) { + rc = inject_fault(vcpu, rc, + current->thread.gmap_addr, + current->thread.gmap_write_flag); + if (rc >= 0) + vsie_page->fault_addr = current->thread.gmap_addr; + } + return rc; +} + +/* + * Retry the previous fault that required guest 2 intervention. This avoids + * one superfluous SIE re-entry and direct exit. + * + * Will ignore any errors. The next SIE fault will do proper fault handling. + */ +static void handle_last_fault(struct kvm_vcpu *vcpu, + struct vsie_page *vsie_page) +{ + if (vsie_page->fault_addr) + kvm_s390_shadow_fault(vcpu, vsie_page->gmap, + vsie_page->fault_addr); + vsie_page->fault_addr = 0; +} + +static inline void clear_vsie_icpt(struct vsie_page *vsie_page) +{ + vsie_page->scb_s.icptcode = 0; +} + +/* rewind the psw and clear the vsie icpt, so we can retry execution */ +static void retry_vsie_icpt(struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + int ilen = insn_length(scb_s->ipa >> 8); + + /* take care of EXECUTE instructions */ + if (scb_s->icptstatus & 1) { + ilen = (scb_s->icptstatus >> 4) & 0x6; + if (!ilen) + ilen = 4; + } + scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, ilen); + clear_vsie_icpt(vsie_page); +} + +/* + * Try to shadow + enable the guest 2 provided facility list. + * Retry instruction execution if enabled for and provided by guest 2. + * + * Returns: - 0 if handled (retry or guest 2 icpt) + * - > 0 if control has to be given to guest 2 + */ +static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + __u32 fac = vsie_page->scb_o->fac & 0x7ffffff8U; + + if (fac && test_kvm_facility(vcpu->kvm, 7)) { + retry_vsie_icpt(vsie_page); + if (read_guest_real(vcpu, fac, &vsie_page->fac, + sizeof(vsie_page->fac))) + return set_validity_icpt(scb_s, 0x1090U); + scb_s->fac = (__u32)(__u64) &vsie_page->fac; + } + return 0; +} + +/* + * Run the vsie on a shadow scb and a shadow gmap, without any further + * sanity checks, handling SIE faults. + * + * Returns: - 0 everything went fine + * - > 0 if control has to be given to guest 2 + * - < 0 if an error occurred + */ +static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; + int rc; + + handle_last_fault(vcpu, vsie_page); + + if (need_resched()) + schedule(); + if (test_cpu_flag(CIF_MCCK_PENDING)) + s390_handle_mcck(); + + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + local_irq_disable(); + kvm_guest_enter(); + local_irq_enable(); + + rc = sie64a(scb_s, vcpu->run->s.regs.gprs); + + local_irq_disable(); + kvm_guest_exit(); + local_irq_enable(); + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + + if (rc > 0) + rc = 0; /* we could still have an icpt */ + else if (rc == -EFAULT) + return handle_fault(vcpu, vsie_page); + + switch (scb_s->icptcode) { + case ICPT_INST: + if (scb_s->ipa == 0xb2b0) + rc = handle_stfle(vcpu, vsie_page); + break; + case ICPT_STOP: + /* stop not requested by g2 - must have been a kick */ + if (!(atomic_read(&scb_o->cpuflags) & CPUSTAT_STOP_INT)) + clear_vsie_icpt(vsie_page); + break; + case ICPT_VALIDITY: + if ((scb_s->ipa & 0xf000) != 0xf000) + scb_s->ipa += 0x1000; + break; + } + return rc; +} + +static void release_gmap_shadow(struct vsie_page *vsie_page) +{ + if (vsie_page->gmap) + gmap_put(vsie_page->gmap); + WRITE_ONCE(vsie_page->gmap, NULL); + prefix_unmapped(vsie_page); +} + +static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, + struct vsie_page *vsie_page) +{ + unsigned long asce; + union ctlreg0 cr0; + struct gmap *gmap; + int edat; + + asce = vcpu->arch.sie_block->gcr[1]; + cr0.val = vcpu->arch.sie_block->gcr[0]; + edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8); + edat += edat && test_kvm_facility(vcpu->kvm, 78); + + /* + * ASCE or EDAT could have changed since last icpt, or the gmap + * we're holding has been unshadowed. If the gmap is still valid, + * we can safely reuse it. + */ + if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) + return 0; + + /* release the old shadow - if any, and mark the prefix as unmapped */ + release_gmap_shadow(vsie_page); + gmap = gmap_shadow(vcpu->arch.gmap, asce, edat); + if (IS_ERR(gmap)) + return PTR_ERR(gmap); + gmap->private = vcpu->kvm; + WRITE_ONCE(vsie_page->gmap, gmap); + return 0; +} + +/* + * Register the shadow scb at the VCPU, e.g. for kicking out of vsie. + */ +static void register_shadow_scb(struct kvm_vcpu *vcpu, + struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + + WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s); + /* + * External calls have to lead to a kick of the vcpu and + * therefore the vsie -> Simulate Wait state. + */ + atomic_or(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); + /* + * We have to adjust the g3 epoch by the g2 epoch. The epoch will + * automatically be adjusted on tod clock changes via kvm_sync_clock. + */ + preempt_disable(); + scb_s->epoch += vcpu->kvm->arch.epoch; + preempt_enable(); +} + +/* + * Unregister a shadow scb from a VCPU. + */ +static void unregister_shadow_scb(struct kvm_vcpu *vcpu) +{ + atomic_andnot(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); + WRITE_ONCE(vcpu->arch.vsie_block, NULL); +} + +/* + * Run the vsie on a shadowed scb, managing the gmap shadow, handling + * prefix pages and faults. + * + * Returns: - 0 if no errors occurred + * - > 0 if control has to be given to guest 2 + * - -ENOMEM if out of memory + */ +static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + int rc = 0; + + while (1) { + rc = acquire_gmap_shadow(vcpu, vsie_page); + if (!rc) + rc = map_prefix(vcpu, vsie_page); + if (!rc) { + gmap_enable(vsie_page->gmap); + update_intervention_requests(vsie_page); + rc = do_vsie_run(vcpu, vsie_page); + gmap_enable(vcpu->arch.gmap); + } + atomic_andnot(PROG_BLOCK_SIE, &scb_s->prog20); + + if (rc == -EAGAIN) + rc = 0; + if (rc || scb_s->icptcode || signal_pending(current) || + kvm_s390_vcpu_has_irq(vcpu, 0)) + break; + }; + + if (rc == -EFAULT) { + /* + * Addressing exceptions are always presentes as intercepts. + * As addressing exceptions are suppressing and our guest 3 PSW + * points at the responsible instruction, we have to + * forward the PSW and set the ilc. If we can't read guest 3 + * instruction, we can use an arbitrary ilc. Let's always use + * ilen = 4 for now, so we can avoid reading in guest 3 virtual + * memory. (we could also fake the shadow so the hardware + * handles it). + */ + scb_s->icptcode = ICPT_PROGI; + scb_s->iprcc = PGM_ADDRESSING; + scb_s->pgmilc = 4; + scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, 4); + } + return rc; +} + +/* + * Get or create a vsie page for a scb address. + * + * Returns: - address of a vsie page (cached or new one) + * - NULL if the same scb address is already used by another VCPU + * - ERR_PTR(-ENOMEM) if out of memory + */ +static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr) +{ + struct vsie_page *vsie_page; + struct page *page; + int nr_vcpus; + + rcu_read_lock(); + page = radix_tree_lookup(&kvm->arch.vsie.addr_to_page, addr >> 9); + rcu_read_unlock(); + if (page) { + if (page_ref_inc_return(page) == 2) + return page_to_virt(page); + page_ref_dec(page); + } + + /* + * We want at least #online_vcpus shadows, so every VCPU can execute + * the VSIE in parallel. + */ + nr_vcpus = atomic_read(&kvm->online_vcpus); + + mutex_lock(&kvm->arch.vsie.mutex); + if (kvm->arch.vsie.page_count < nr_vcpus) { + page = alloc_page(GFP_KERNEL | __GFP_ZERO | GFP_DMA); + if (!page) { + mutex_unlock(&kvm->arch.vsie.mutex); + return ERR_PTR(-ENOMEM); + } + page_ref_inc(page); + kvm->arch.vsie.pages[kvm->arch.vsie.page_count] = page; + kvm->arch.vsie.page_count++; + } else { + /* reuse an existing entry that belongs to nobody */ + while (true) { + page = kvm->arch.vsie.pages[kvm->arch.vsie.next]; + if (page_ref_inc_return(page) == 2) + break; + page_ref_dec(page); + kvm->arch.vsie.next++; + kvm->arch.vsie.next %= nr_vcpus; + } + radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9); + } + page->index = addr; + /* double use of the same address */ + if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, page)) { + page_ref_dec(page); + mutex_unlock(&kvm->arch.vsie.mutex); + return NULL; + } + mutex_unlock(&kvm->arch.vsie.mutex); + + vsie_page = page_to_virt(page); + memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block)); + release_gmap_shadow(vsie_page); + vsie_page->fault_addr = 0; + vsie_page->scb_s.ihcpu = 0xffffU; + return vsie_page; +} + +/* put a vsie page acquired via get_vsie_page */ +static void put_vsie_page(struct kvm *kvm, struct vsie_page *vsie_page) +{ + struct page *page = pfn_to_page(__pa(vsie_page) >> PAGE_SHIFT); + + page_ref_dec(page); +} + +int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu) +{ + struct vsie_page *vsie_page; + unsigned long scb_addr; + int rc; + + vcpu->stat.instruction_sie++; + if (!test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIEF2)) + return -EOPNOTSUPP; + if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); + + BUILD_BUG_ON(sizeof(struct vsie_page) != 4096); + scb_addr = kvm_s390_get_base_disp_s(vcpu, NULL); + + /* 512 byte alignment */ + if (unlikely(scb_addr & 0x1ffUL)) + return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); + + if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0)) + return 0; + + vsie_page = get_vsie_page(vcpu->kvm, scb_addr); + if (IS_ERR(vsie_page)) + return PTR_ERR(vsie_page); + else if (!vsie_page) + /* double use of sie control block - simply do nothing */ + return 0; + + rc = pin_scb(vcpu, vsie_page, scb_addr); + if (rc) + goto out_put; + rc = shadow_scb(vcpu, vsie_page); + if (rc) + goto out_unpin_scb; + rc = pin_blocks(vcpu, vsie_page); + if (rc) + goto out_unshadow; + register_shadow_scb(vcpu, vsie_page); + rc = vsie_run(vcpu, vsie_page); + unregister_shadow_scb(vcpu); + unpin_blocks(vcpu, vsie_page); +out_unshadow: + unshadow_scb(vcpu, vsie_page); +out_unpin_scb: + unpin_scb(vcpu, vsie_page, scb_addr); +out_put: + put_vsie_page(vcpu->kvm, vsie_page); + + return rc < 0 ? rc : 0; +} + +/* Init the vsie data structures. To be called when a vm is initialized. */ +void kvm_s390_vsie_init(struct kvm *kvm) +{ + mutex_init(&kvm->arch.vsie.mutex); + INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL); +} + +/* Destroy the vsie data structures. To be called when a vm is destroyed. */ +void kvm_s390_vsie_destroy(struct kvm *kvm) +{ + struct vsie_page *vsie_page; + struct page *page; + int i; + + mutex_lock(&kvm->arch.vsie.mutex); + for (i = 0; i < kvm->arch.vsie.page_count; i++) { + page = kvm->arch.vsie.pages[i]; + kvm->arch.vsie.pages[i] = NULL; + vsie_page = page_to_virt(page); + release_gmap_shadow(vsie_page); + /* free the radix tree entry */ + radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9); + __free_page(page); + } + kvm->arch.vsie.page_count = 0; + mutex_unlock(&kvm->arch.vsie.mutex); +} + +void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu) +{ + struct kvm_s390_sie_block *scb = READ_ONCE(vcpu->arch.vsie_block); + + /* + * Even if the VCPU lets go of the shadow sie block reference, it is + * still valid in the cache. So we can safely kick it. + */ + if (scb) { + atomic_or(PROG_BLOCK_SIE, &scb->prog20); + if (scb->prog0c & PROG_IN_SIE) + atomic_or(CPUSTAT_STOP_INT, &scb->cpuflags); + } +} |