diff options
Diffstat (limited to 'arch/s390/kvm/vsie.c')
| -rw-r--r-- | arch/s390/kvm/vsie.c | 788 |
1 files changed, 603 insertions, 185 deletions
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 715c19c45d9a..b526621d2a1b 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -1,11 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0 /* * 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. + * Copyright IBM Corp. 2016, 2018 * * Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com> */ @@ -15,15 +12,22 @@ #include <linux/list.h> #include <linux/bitmap.h> #include <linux/sched/signal.h> +#include <linux/io.h> +#include <linux/mman.h> #include <asm/gmap.h> #include <asm/mmu_context.h> #include <asm/sclp.h> #include <asm/nmi.h> #include <asm/dis.h> +#include <asm/facility.h> #include "kvm-s390.h" #include "gaccess.h" +enum vsie_page_flags { + VSIE_PAGE_IN_USE = 0, +}; + struct vsie_page { struct kvm_s390_sie_block scb_s; /* 0x0000 */ /* @@ -31,17 +35,56 @@ struct vsie_page { * the same offset as that in struct sie_page! */ struct mcck_volatile_info mcck_info; /* 0x0200 */ - /* the pinned originial scb */ + /* + * The pinned original scb. Be aware that other VCPUs can modify + * it while we read from it. Values that are used for conditions or + * are reused conditionally, should be accessed via READ_ONCE. + */ struct kvm_s390_sie_block *scb_o; /* 0x0218 */ /* the shadow gmap in use by the vsie_page */ struct gmap *gmap; /* 0x0220 */ /* address of the last reported fault to guest2 */ unsigned long fault_addr; /* 0x0228 */ - __u8 reserved[0x0700 - 0x0230]; /* 0x0230 */ + /* calculated guest addresses of satellite control blocks */ + gpa_t sca_gpa; /* 0x0230 */ + gpa_t itdba_gpa; /* 0x0238 */ + gpa_t gvrd_gpa; /* 0x0240 */ + gpa_t riccbd_gpa; /* 0x0248 */ + gpa_t sdnx_gpa; /* 0x0250 */ + /* + * guest address of the original SCB. Remains set for free vsie + * pages, so we can properly look them up in our addr_to_page + * radix tree. + */ + gpa_t scb_gpa; /* 0x0258 */ + /* + * Flags: must be set/cleared atomically after the vsie page can be + * looked up by other CPUs. + */ + unsigned long flags; /* 0x0260 */ + __u8 reserved[0x0700 - 0x0268]; /* 0x0268 */ struct kvm_s390_crypto_cb crycb; /* 0x0700 */ __u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */ }; +/** + * gmap_shadow_valid() - check if a shadow guest address space matches the + * given properties and is still valid + * @sg: pointer to the shadow guest address space structure + * @asce: ASCE for which the shadow table is requested + * @edat_level: edat level to be used for the shadow translation + * + * Returns 1 if the gmap shadow is still valid and matches the given + * properties, the caller can continue using it. Returns 0 otherwise; the + * caller has to request a new shadow gmap in this case. + */ +int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level) +{ + if (sg->removed) + return 0; + return sg->orig_asce == asce && sg->edat_level == edat_level; +} + /* trigger a validity icpt for the given scb */ static int set_validity_icpt(struct kvm_s390_sie_block *scb, __u16 reason_code) @@ -128,14 +171,158 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) atomic_set(&scb_s->cpuflags, newflags); return 0; } +/* Copy to APCB FORMAT1 from APCB FORMAT0 */ +static int setup_apcb10(struct kvm_vcpu *vcpu, struct kvm_s390_apcb1 *apcb_s, + unsigned long crycb_gpa, struct kvm_s390_apcb1 *apcb_h) +{ + struct kvm_s390_apcb0 tmp; + unsigned long apcb_gpa; -/* + apcb_gpa = crycb_gpa + offsetof(struct kvm_s390_crypto_cb, apcb0); + + if (read_guest_real(vcpu, apcb_gpa, &tmp, + sizeof(struct kvm_s390_apcb0))) + return -EFAULT; + + apcb_s->apm[0] = apcb_h->apm[0] & tmp.apm[0]; + apcb_s->aqm[0] = apcb_h->aqm[0] & tmp.aqm[0] & 0xffff000000000000UL; + apcb_s->adm[0] = apcb_h->adm[0] & tmp.adm[0] & 0xffff000000000000UL; + + return 0; + +} + +/** + * setup_apcb00 - Copy to APCB FORMAT0 from APCB FORMAT0 + * @vcpu: pointer to the virtual CPU + * @apcb_s: pointer to start of apcb in the shadow crycb + * @crycb_gpa: guest physical address to start of original guest crycb + * @apcb_h: pointer to start of apcb in the guest1 + * + * Returns 0 and -EFAULT on error reading guest apcb + */ +static int setup_apcb00(struct kvm_vcpu *vcpu, unsigned long *apcb_s, + unsigned long crycb_gpa, unsigned long *apcb_h) +{ + unsigned long apcb_gpa; + + apcb_gpa = crycb_gpa + offsetof(struct kvm_s390_crypto_cb, apcb0); + + if (read_guest_real(vcpu, apcb_gpa, apcb_s, + sizeof(struct kvm_s390_apcb0))) + return -EFAULT; + + bitmap_and(apcb_s, apcb_s, apcb_h, + BITS_PER_BYTE * sizeof(struct kvm_s390_apcb0)); + + return 0; +} + +/** + * setup_apcb11 - Copy the FORMAT1 APCB from the guest to the shadow CRYCB + * @vcpu: pointer to the virtual CPU + * @apcb_s: pointer to start of apcb in the shadow crycb + * @crycb_gpa: guest physical address to start of original guest crycb + * @apcb_h: pointer to start of apcb in the host + * + * Returns 0 and -EFAULT on error reading guest apcb + */ +static int setup_apcb11(struct kvm_vcpu *vcpu, unsigned long *apcb_s, + unsigned long crycb_gpa, + unsigned long *apcb_h) +{ + unsigned long apcb_gpa; + + apcb_gpa = crycb_gpa + offsetof(struct kvm_s390_crypto_cb, apcb1); + + if (read_guest_real(vcpu, apcb_gpa, apcb_s, + sizeof(struct kvm_s390_apcb1))) + return -EFAULT; + + bitmap_and(apcb_s, apcb_s, apcb_h, + BITS_PER_BYTE * sizeof(struct kvm_s390_apcb1)); + + return 0; +} + +/** + * setup_apcb - Create a shadow copy of the apcb. + * @vcpu: pointer to the virtual CPU + * @crycb_s: pointer to shadow crycb + * @crycb_gpa: guest physical address of original guest crycb + * @crycb_h: pointer to the host crycb + * @fmt_o: format of the original guest crycb. + * @fmt_h: format of the host crycb. + * + * Checks the compatibility between the guest and host crycb and calls the + * appropriate copy function. + * + * Return 0 or an error number if the guest and host crycb are incompatible. + */ +static int setup_apcb(struct kvm_vcpu *vcpu, struct kvm_s390_crypto_cb *crycb_s, + const u32 crycb_gpa, + struct kvm_s390_crypto_cb *crycb_h, + int fmt_o, int fmt_h) +{ + switch (fmt_o) { + case CRYCB_FORMAT2: + if ((crycb_gpa & PAGE_MASK) != ((crycb_gpa + 256) & PAGE_MASK)) + return -EACCES; + if (fmt_h != CRYCB_FORMAT2) + return -EINVAL; + return setup_apcb11(vcpu, (unsigned long *)&crycb_s->apcb1, + crycb_gpa, + (unsigned long *)&crycb_h->apcb1); + case CRYCB_FORMAT1: + switch (fmt_h) { + case CRYCB_FORMAT2: + return setup_apcb10(vcpu, &crycb_s->apcb1, + crycb_gpa, + &crycb_h->apcb1); + case CRYCB_FORMAT1: + return setup_apcb00(vcpu, + (unsigned long *) &crycb_s->apcb0, + crycb_gpa, + (unsigned long *) &crycb_h->apcb0); + } + break; + case CRYCB_FORMAT0: + if ((crycb_gpa & PAGE_MASK) != ((crycb_gpa + 32) & PAGE_MASK)) + return -EACCES; + + switch (fmt_h) { + case CRYCB_FORMAT2: + return setup_apcb10(vcpu, &crycb_s->apcb1, + crycb_gpa, + &crycb_h->apcb1); + case CRYCB_FORMAT1: + case CRYCB_FORMAT0: + return setup_apcb00(vcpu, + (unsigned long *) &crycb_s->apcb0, + crycb_gpa, + (unsigned long *) &crycb_h->apcb0); + } + } + return -EINVAL; +} + +/** + * shadow_crycb - Create a shadow copy of the crycb block + * @vcpu: a pointer to the virtual CPU + * @vsie_page: a pointer to internal date used for the vSIE + * * 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 + * We accept format-1 or format-2, but we convert format-1 into format-2 + * in the shadow CRYCB. + * Using format-2 enables the firmware to choose the right format when + * scheduling the SIE. * There is nothing to do for format-0. * + * This function centralize the issuing of set_validity_icpt() for all + * the subfunctions working on the crycb. + * * Returns: - 0 if shadowed or nothing to do * - > 0 if control has to be given to guest 2 */ @@ -143,34 +330,57 @@ 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; + const uint32_t crycbd_o = READ_ONCE(scb_o->crycbd); + const u32 crycb_addr = crycbd_o & 0x7ffffff8U; unsigned long *b1, *b2; u8 ecb3_flags; + u32 ecd_flags; + int apie_h; + int apie_s; + int key_msk = test_kvm_facility(vcpu->kvm, 76); + int fmt_o = crycbd_o & CRYCB_FORMAT_MASK; + int fmt_h = vcpu->arch.sie_block->crycbd & CRYCB_FORMAT_MASK; + int ret = 0; 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)) + + apie_h = vcpu->arch.sie_block->eca & ECA_APIE; + apie_s = apie_h & scb_o->eca; + if (!apie_s && (!key_msk || (fmt_o == CRYCB_FORMAT0))) return 0; + + if (!crycb_addr) + return set_validity_icpt(scb_s, 0x0039U); + + if (fmt_o == CRYCB_FORMAT1) + if ((crycb_addr & PAGE_MASK) != + ((crycb_addr + 128) & PAGE_MASK)) + return set_validity_icpt(scb_s, 0x003CU); + + if (apie_s) { + ret = setup_apcb(vcpu, &vsie_page->crycb, crycb_addr, + vcpu->kvm->arch.crypto.crycb, + fmt_o, fmt_h); + if (ret) + goto end; + scb_s->eca |= scb_o->eca & ECA_APIE; + } + /* 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); + ecd_flags = scb_o->ecd & vcpu->arch.sie_block->ecd & + (ECD_ECC | ECD_HMAC); + if (!ecb3_flags && !ecd_flags) + goto end; /* copy only the wrapping keys */ - if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56)) + if (read_guest_real(vcpu, crycb_addr + 72, + vsie_page->crycb.dea_wrapping_key_mask, 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; + scb_s->ecd |= ecd_flags; /* xor both blocks in one run */ b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask; @@ -178,6 +388,16 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) 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); +end: + switch (ret) { + case -EINVAL: + return set_validity_icpt(scb_s, 0x0022U); + case -EFAULT: + return set_validity_icpt(scb_s, 0x0035U); + case -EACCES: + return set_validity_icpt(scb_s, 0x003CU); + } + scb_s->crycbd = (u32)virt_to_phys(&vsie_page->crycb) | CRYCB_FORMAT2; return 0; } @@ -186,12 +406,15 @@ 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; + /* READ_ONCE does not work on bitfields - use a temporary variable */ + const uint32_t __new_ibc = scb_o->ibc; + const uint32_t new_ibc = READ_ONCE(__new_ibc) & 0x0fffU; __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; + if (vcpu->kvm->arch.model.ibc && new_ibc) { + scb_s->ibc = new_ibc; /* takte care of the minimum ibc level of the machine */ if (scb_s->ibc < min_ibc) scb_s->ibc = min_ibc; @@ -226,6 +449,12 @@ static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) memcpy(scb_o->gcr, scb_s->gcr, 128); scb_o->pp = scb_s->pp; + /* branch prediction */ + if (test_kvm_facility(vcpu->kvm, 82)) { + scb_o->fpf &= ~FPF_BPBC; + scb_o->fpf |= scb_s->fpf & FPF_BPBC; + } + /* interrupt intercept */ switch (scb_s->icptcode) { case ICPT_PROGI: @@ -234,11 +463,6 @@ static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) 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) @@ -256,6 +480,10 @@ 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; + /* READ_ONCE does not work on bitfields - use a temporary variable */ + const uint32_t __new_prefix = scb_o->prefix; + const uint32_t new_prefix = READ_ONCE(__new_prefix); + const bool wants_tx = READ_ONCE(scb_o->ecb) & ECB_TE; bool had_tx = scb_s->ecb & ECB_TE; unsigned long new_mso = 0; int rc; @@ -268,6 +496,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) scb_s->ecb3 = 0; scb_s->ecd = 0; scb_s->fac = 0; + scb_s->fpf = 0; rc = prepare_cpuflags(vcpu, vsie_page); if (rc) @@ -302,16 +531,16 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) scb_s->icpua = scb_o->icpua; if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM)) - new_mso = scb_o->mso & 0xfffffffffff00000UL; + new_mso = READ_ONCE(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) + if (scb_s->mso != new_mso || scb_s->prefix != new_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; + scb_s->prefix = new_prefix; - /* We have to definetly flush the tlb if this scb never ran */ + /* We have to definitely flush the tlb if this scb never ran */ if (scb_s->ihcpu != 0xffffU) scb_s->ihcpu = scb_o->ihcpu; @@ -320,13 +549,26 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) /* 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 & ECB_HOSTPROTINT; + /* + * CPU Topology + * This facility only uses the utility field of the SCA and none of + * the cpu entries that are problematic with the other interpretation + * facilities so we can pass it through + */ + if (test_kvm_facility(vcpu->kvm, 11)) + scb_s->ecb |= scb_o->ecb & ECB_PTF; /* transactional execution */ - if (test_kvm_facility(vcpu->kvm, 73)) { + if (test_kvm_facility(vcpu->kvm, 73) && wants_tx) { /* remap the prefix is tx is toggled on */ - if ((scb_o->ecb & ECB_TE) && !had_tx) + if (!had_tx) prefix_unmapped(vsie_page); - scb_s->ecb |= scb_o->ecb & ECB_TE; + scb_s->ecb |= ECB_TE; } + /* specification exception interpretation */ + scb_s->ecb |= scb_o->ecb & ECB_SPECI; + /* branch prediction */ + if (test_kvm_facility(vcpu->kvm, 82)) + scb_s->fpf |= scb_o->fpf & FPF_BPBC; /* SIMD */ if (test_kvm_facility(vcpu->kvm, 129)) { scb_s->eca |= scb_o->eca & ECA_VX; @@ -349,6 +591,18 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) scb_s->eca |= scb_o->eca & ECA_IB; if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI)) scb_s->eca |= scb_o->eca & ECA_CEI; + /* Epoch Extension */ + if (test_kvm_facility(vcpu->kvm, 139)) { + scb_s->ecd |= scb_o->ecd & ECD_MEF; + scb_s->epdx = scb_o->epdx; + } + + /* etoken */ + if (test_kvm_facility(vcpu->kvm, 156)) + scb_s->ecd |= scb_o->ecd & ECD_ETOKENF; + + scb_s->hpid = HPID_VSIE; + scb_s->cpnc = scb_o->cpnc; prepare_ibc(vcpu, vsie_page); rc = shadow_crycb(vcpu, vsie_page); @@ -364,24 +618,18 @@ void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start, 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) + cur = READ_ONCE(kvm->arch.vsie.pages[i]); + if (!cur) continue; - cur = page_to_virt(page); if (READ_ONCE(cur->gmap) != gmap) continue; prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT; @@ -419,10 +667,10 @@ static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *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); + rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix, NULL); if (!rc && (scb_s->ecb & ECB_TE)) rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, - prefix + PAGE_SIZE); + prefix + PAGE_SIZE, NULL); /* * We don't have to mprotect, we will be called for all unshadows. * SIE will detect if protection applies and trigger a validity. @@ -440,34 +688,22 @@ static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) * * 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)) + page = gfn_to_page(kvm, gpa_to_gfn(gpa)); + if (!page) 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); + *hpa = (hpa_t)page_to_phys(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); + kvm_release_page_dirty(pfn_to_page(hpa >> PAGE_SHIFT)); /* mark the page always as dirty for migration */ mark_page_dirty(kvm, gpa_to_gfn(gpa)); } @@ -475,46 +711,42 @@ static void unpin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t hpa) /* 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); + unpin_guest_page(vcpu->kvm, vsie_page->sca_gpa, hpa); + vsie_page->sca_gpa = 0; 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); + unpin_guest_page(vcpu->kvm, vsie_page->itdba_gpa, hpa); + vsie_page->itdba_gpa = 0; scb_s->itdba = 0; } hpa = scb_s->gvrd; if (hpa) { - gpa = scb_o->gvrd & ~0x1ffUL; - unpin_guest_page(vcpu->kvm, gpa, hpa); + unpin_guest_page(vcpu->kvm, vsie_page->gvrd_gpa, hpa); + vsie_page->gvrd_gpa = 0; scb_s->gvrd = 0; } hpa = scb_s->riccbd; if (hpa) { - gpa = scb_o->riccbd & ~0x3fUL; - unpin_guest_page(vcpu->kvm, gpa, hpa); + unpin_guest_page(vcpu->kvm, vsie_page->riccbd_gpa, hpa); + vsie_page->riccbd_gpa = 0; scb_s->riccbd = 0; } hpa = scb_s->sdnxo; if (hpa) { - gpa = scb_o->sdnxo; - unpin_guest_page(vcpu->kvm, gpa, hpa); + unpin_guest_page(vcpu->kvm, vsie_page->sdnx_gpa, hpa); + vsie_page->sdnx_gpa = 0; scb_s->sdnxo = 0; } } @@ -541,46 +773,48 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) gpa_t gpa; int rc = 0; - gpa = scb_o->scaol & ~0xfUL; + gpa = READ_ONCE(scb_o->scaol) & ~0xfUL; if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO)) - gpa |= (u64) scb_o->scaoh << 32; + gpa |= (u64) READ_ONCE(scb_o->scaoh) << 32; if (gpa) { - if (!(gpa & ~0x1fffUL)) + if (gpa < 2 * PAGE_SIZE) 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)) + ((gpa + offsetof(struct bsca_block, cpu[0]) - 1) & PAGE_MASK)) rc = set_validity_icpt(scb_s, 0x003bU); if (!rc) { rc = pin_guest_page(vcpu->kvm, gpa, &hpa); - if (rc == -EINVAL) + if (rc) rc = set_validity_icpt(scb_s, 0x0034U); } if (rc) goto unpin; + vsie_page->sca_gpa = gpa; scb_s->scaoh = (u32)((u64)hpa >> 32); scb_s->scaol = (u32)(u64)hpa; } - gpa = scb_o->itdba & ~0xffUL; + gpa = READ_ONCE(scb_o->itdba) & ~0xffUL; if (gpa && (scb_s->ecb & ECB_TE)) { - if (!(gpa & ~0x1fffU)) { + if (gpa < 2 * PAGE_SIZE) { 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) + if (rc) { rc = set_validity_icpt(scb_s, 0x0080U); - if (rc) goto unpin; + } + vsie_page->itdba_gpa = gpa; scb_s->itdba = hpa; } - gpa = scb_o->gvrd & ~0x1ffUL; + gpa = READ_ONCE(scb_o->gvrd) & ~0x1ffUL; if (gpa && (scb_s->eca & ECA_VX) && !(scb_s->ecd & ECD_HOSTREGMGMT)) { - if (!(gpa & ~0x1fffUL)) { + if (gpa < 2 * PAGE_SIZE) { rc = set_validity_icpt(scb_s, 0x1310U); goto unpin; } @@ -589,34 +823,37 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) * if this block gets bigger, we have to shadow it. */ rc = pin_guest_page(vcpu->kvm, gpa, &hpa); - if (rc == -EINVAL) + if (rc) { rc = set_validity_icpt(scb_s, 0x1310U); - if (rc) goto unpin; + } + vsie_page->gvrd_gpa = gpa; scb_s->gvrd = hpa; } - gpa = scb_o->riccbd & ~0x3fUL; + gpa = READ_ONCE(scb_o->riccbd) & ~0x3fUL; if (gpa && (scb_s->ecb3 & ECB3_RI)) { - if (!(gpa & ~0x1fffUL)) { + if (gpa < 2 * PAGE_SIZE) { 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) + if (rc) { rc = set_validity_icpt(scb_s, 0x0043U); - /* Validity 0x0044 will be checked by SIE */ - if (rc) goto unpin; + } + /* Validity 0x0044 will be checked by SIE */ + vsie_page->riccbd_gpa = gpa; scb_s->riccbd = hpa; } - if ((scb_s->ecb & ECB_GS) && !(scb_s->ecd & ECD_HOSTREGMGMT)) { + if (((scb_s->ecb & ECB_GS) && !(scb_s->ecd & ECD_HOSTREGMGMT)) || + (scb_s->ecd & ECD_ETOKENF)) { unsigned long sdnxc; - gpa = scb_o->sdnxo & ~0xfUL; - sdnxc = scb_o->sdnxo & 0xfUL; - if (!gpa || !(gpa & ~0x1fffUL)) { + gpa = READ_ONCE(scb_o->sdnxo) & ~0xfUL; + sdnxc = READ_ONCE(scb_o->sdnxo) & 0xfUL; + if (!gpa || gpa < 2 * PAGE_SIZE) { rc = set_validity_icpt(scb_s, 0x10b0U); goto unpin; } @@ -632,10 +869,11 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) * cross page boundaries */ rc = pin_guest_page(vcpu->kvm, gpa, &hpa); - if (rc == -EINVAL) + if (rc) { rc = set_validity_icpt(scb_s, 0x10b0U); - if (rc) goto unpin; + } + vsie_page->sdnx_gpa = gpa; scb_s->sdnxo = hpa | sdnxc; } return 0; @@ -648,7 +886,7 @@ unpin: 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; + hpa_t hpa = virt_to_phys(vsie_page->scb_o); if (hpa) unpin_guest_page(vcpu->kvm, gpa, hpa); @@ -660,7 +898,6 @@ static void unpin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, * * 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) @@ -669,14 +906,13 @@ static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, int rc; rc = pin_guest_page(vcpu->kvm, gpa, &hpa); - if (rc == -EINVAL) { + if (rc) { rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - if (!rc) - rc = 1; + WARN_ON_ONCE(rc); + return 1; } - if (!rc) - vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa; - return rc; + vsie_page->scb_o = phys_to_virt(hpa); + return 0; } /* @@ -695,7 +931,7 @@ static int inject_fault(struct kvm_vcpu *vcpu, __u16 code, __u64 vaddr, (vaddr & 0xfffffffffffff000UL) | /* 52-53: store / fetch */ (((unsigned int) !write_flag) + 1) << 10, - /* 62-63: asce id (alway primary == 0) */ + /* 62-63: asce id (always primary == 0) */ .exc_access_id = 0, /* always primary */ .op_access_id = 0, /* not MVPG */ }; @@ -719,19 +955,19 @@ static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) { int rc; - if (current->thread.gmap_int_code == PGM_PROTECTION) + if ((current->thread.gmap_int_code & PGM_INT_CODE_MASK) == PGM_PROTECTION) /* we can directly forward all protection exceptions */ return inject_fault(vcpu, PGM_PROTECTION, - current->thread.gmap_addr, 1); + current->thread.gmap_teid.addr * PAGE_SIZE, 1); rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, - current->thread.gmap_addr); + current->thread.gmap_teid.addr * PAGE_SIZE, NULL); if (rc > 0) { rc = inject_fault(vcpu, rc, - current->thread.gmap_addr, - current->thread.gmap_write_flag); + current->thread.gmap_teid.addr * PAGE_SIZE, + kvm_s390_cur_gmap_fault_is_write()); if (rc >= 0) - vsie_page->fault_addr = current->thread.gmap_addr; + vsie_page->fault_addr = current->thread.gmap_teid.addr * PAGE_SIZE; } return rc; } @@ -747,7 +983,7 @@ static void handle_last_fault(struct kvm_vcpu *vcpu, { if (vsie_page->fault_addr) kvm_s390_shadow_fault(vcpu, vsie_page->gmap, - vsie_page->fault_addr); + vsie_page->fault_addr, NULL); vsie_page->fault_addr = 0; } @@ -782,19 +1018,125 @@ static void retry_vsie_icpt(struct vsie_page *vsie_page) 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; + __u32 fac = READ_ONCE(vsie_page->scb_o->fac); + /* + * Alternate-STFLE-Interpretive-Execution facilities are not supported + * -> format-0 flcb + */ if (fac && test_kvm_facility(vcpu->kvm, 7)) { retry_vsie_icpt(vsie_page); + /* + * The facility list origin (FLO) is in bits 1 - 28 of the FLD + * so we need to mask here before reading. + */ + fac = fac & 0x7ffffff8U; + /* + * format-0 -> size of nested guest's facility list == guest's size + * guest's size == host's size, since STFLE is interpretatively executed + * using a format-0 for the guest, too. + */ if (read_guest_real(vcpu, fac, &vsie_page->fac, - sizeof(vsie_page->fac))) + stfle_size() * sizeof(u64))) return set_validity_icpt(scb_s, 0x1090U); - scb_s->fac = (__u32)(__u64) &vsie_page->fac; + scb_s->fac = (u32)virt_to_phys(&vsie_page->fac); } return 0; } /* + * Get a register for a nested guest. + * @vcpu the vcpu of the guest + * @vsie_page the vsie_page for the nested guest + * @reg the register number, the upper 4 bits are ignored. + * returns: the value of the register. + */ +static u64 vsie_get_register(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, u8 reg) +{ + /* no need to validate the parameter and/or perform error handling */ + reg &= 0xf; + switch (reg) { + case 15: + return vsie_page->scb_s.gg15; + case 14: + return vsie_page->scb_s.gg14; + default: + return vcpu->run->s.regs.gprs[reg]; + } +} + +static int vsie_handle_mvpg(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{ + struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; + unsigned long pei_dest, pei_src, src, dest, mask, prefix; + u64 *pei_block = &vsie_page->scb_o->mcic; + int edat, rc_dest, rc_src; + union ctlreg0 cr0; + + cr0.val = vcpu->arch.sie_block->gcr[0]; + edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8); + mask = _kvm_s390_logical_to_effective(&scb_s->gpsw, PAGE_MASK); + prefix = scb_s->prefix << GUEST_PREFIX_SHIFT; + + dest = vsie_get_register(vcpu, vsie_page, scb_s->ipb >> 20) & mask; + dest = _kvm_s390_real_to_abs(prefix, dest) + scb_s->mso; + src = vsie_get_register(vcpu, vsie_page, scb_s->ipb >> 16) & mask; + src = _kvm_s390_real_to_abs(prefix, src) + scb_s->mso; + + rc_dest = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, dest, &pei_dest); + rc_src = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, src, &pei_src); + /* + * Either everything went well, or something non-critical went wrong + * e.g. because of a race. In either case, simply retry. + */ + if (rc_dest == -EAGAIN || rc_src == -EAGAIN || (!rc_dest && !rc_src)) { + retry_vsie_icpt(vsie_page); + return -EAGAIN; + } + /* Something more serious went wrong, propagate the error */ + if (rc_dest < 0) + return rc_dest; + if (rc_src < 0) + return rc_src; + + /* The only possible suppressing exception: just deliver it */ + if (rc_dest == PGM_TRANSLATION_SPEC || rc_src == PGM_TRANSLATION_SPEC) { + clear_vsie_icpt(vsie_page); + rc_dest = kvm_s390_inject_program_int(vcpu, PGM_TRANSLATION_SPEC); + WARN_ON_ONCE(rc_dest); + return 1; + } + + /* + * Forward the PEI intercept to the guest if it was a page fault, or + * also for segment and region table faults if EDAT applies. + */ + if (edat) { + rc_dest = rc_dest == PGM_ASCE_TYPE ? rc_dest : 0; + rc_src = rc_src == PGM_ASCE_TYPE ? rc_src : 0; + } else { + rc_dest = rc_dest != PGM_PAGE_TRANSLATION ? rc_dest : 0; + rc_src = rc_src != PGM_PAGE_TRANSLATION ? rc_src : 0; + } + if (!rc_dest && !rc_src) { + pei_block[0] = pei_dest; + pei_block[1] = pei_src; + return 1; + } + + retry_vsie_icpt(vsie_page); + + /* + * The host has edat, and the guest does not, or it was an ASCE type + * exception. The host needs to inject the appropriate DAT interrupts + * into the guest. + */ + if (rc_dest) + return inject_fault(vcpu, rc_dest, dest, 1); + return inject_fault(vcpu, rc_src, src, 0); +} + +/* * Run the vsie on a shadow scb and a shadow gmap, without any further * sanity checks, handling SIE faults. * @@ -803,43 +1145,76 @@ static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) * - < 0 if an error occurred */ static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) + __releases(vcpu->kvm->srcu) + __acquires(vcpu->kvm->srcu) { struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; struct kvm_s390_sie_block *scb_o = vsie_page->scb_o; - struct mcck_volatile_info *mcck_info; - struct sie_page *sie_page; - int rc; + int guest_bp_isolation; + int rc = 0; handle_last_fault(vcpu, vsie_page); - if (need_resched()) - schedule(); - if (test_cpu_flag(CIF_MCCK_PENDING)) - s390_handle_mcck(); + kvm_vcpu_srcu_read_unlock(vcpu); - srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); - local_irq_disable(); - guest_enter_irqoff(); - local_irq_enable(); + /* save current guest state of bp isolation override */ + guest_bp_isolation = test_thread_flag(TIF_ISOLATE_BP_GUEST); - rc = sie64a(scb_s, vcpu->run->s.regs.gprs); + /* + * The guest is running with BPBC, so we have to force it on for our + * nested guest. This is done by enabling BPBC globally, so the BPBC + * control in the SCB (which the nested guest can modify) is simply + * ignored. + */ + if (test_kvm_facility(vcpu->kvm, 82) && + vcpu->arch.sie_block->fpf & FPF_BPBC) + set_thread_flag(TIF_ISOLATE_BP_GUEST); - local_irq_disable(); - guest_exit_irqoff(); - local_irq_enable(); - vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + /* + * Simulate a SIE entry of the VCPU (see sie64a), so VCPU blocking + * and VCPU requests also hinder the vSIE from running and lead + * to an immediate exit. kvm_s390_vsie_kick() has to be used to + * also kick the vSIE. + */ + vcpu->arch.sie_block->prog0c |= PROG_IN_SIE; + current->thread.gmap_int_code = 0; + barrier(); + if (!kvm_s390_vcpu_sie_inhibited(vcpu)) { +xfer_to_guest_mode_check: + local_irq_disable(); + xfer_to_guest_mode_prepare(); + if (xfer_to_guest_mode_work_pending()) { + local_irq_enable(); + rc = kvm_xfer_to_guest_mode_handle_work(vcpu); + if (rc) + goto skip_sie; + goto xfer_to_guest_mode_check; + } + guest_timing_enter_irqoff(); + rc = kvm_s390_enter_exit_sie(scb_s, vcpu->run->s.regs.gprs, vsie_page->gmap->asce); + guest_timing_exit_irqoff(); + local_irq_enable(); + } + +skip_sie: + barrier(); + vcpu->arch.sie_block->prog0c &= ~PROG_IN_SIE; + + /* restore guest state for bp isolation override */ + if (!guest_bp_isolation) + clear_thread_flag(TIF_ISOLATE_BP_GUEST); + + kvm_vcpu_srcu_read_lock(vcpu); if (rc == -EINTR) { VCPU_EVENT(vcpu, 3, "%s", "machine check"); - sie_page = container_of(scb_s, struct sie_page, sie_block); - mcck_info = &sie_page->mcck_info; - kvm_s390_reinject_machine_check(vcpu, mcck_info); + kvm_s390_reinject_machine_check(vcpu, &vsie_page->mcck_info); return 0; } if (rc > 0) rc = 0; /* we could still have an icpt */ - else if (rc == -EFAULT) + else if (current->thread.gmap_int_code) return handle_fault(vcpu, vsie_page); switch (scb_s->icptcode) { @@ -856,6 +1231,10 @@ static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) if ((scb_s->ipa & 0xf000) != 0xf000) scb_s->ipa += 0x1000; break; + case ICPT_PARTEXEC: + if (scb_s->ipa == 0xb254) + rc = vsie_handle_mvpg(vcpu, vsie_page); + break; } return rc; } @@ -886,15 +1265,17 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, * 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)) + if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) { + vcpu->kvm->stat.gmap_shadow_reuse++; 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; + vcpu->kvm->stat.gmap_shadow_create++; WRITE_ONCE(vsie_page->gmap, gmap); return 0; } @@ -912,13 +1293,20 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu, * 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); + kvm_s390_set_cpuflags(vcpu, CPUSTAT_WAIT); /* * 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; + + if (scb_s->ecd & ECD_MEF) { + scb_s->epdx += vcpu->kvm->arch.epdx; + if (scb_s->epoch < vcpu->kvm->arch.epoch) + scb_s->epdx += 1; + } + preempt_enable(); } @@ -927,7 +1315,7 @@ static void register_shadow_scb(struct kvm_vcpu *vcpu, */ static void unregister_shadow_scb(struct kvm_vcpu *vcpu) { - atomic_andnot(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); + kvm_s390_clear_cpuflags(vcpu, CPUSTAT_WAIT); WRITE_ONCE(vcpu->arch.vsie_block, NULL); } @@ -949,18 +1337,30 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *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)) + + /* + * Exit the loop if the guest needs to process the intercept + */ + if (rc || scb_s->icptcode) + break; + + /* + * Exit the loop if the host needs to process an intercept, + * but rewind the PSW to re-enter SIE once that's completed + * instead of passing a "no action" intercept to the guest. + */ + if (kvm_s390_vcpu_has_irq(vcpu, 0) || + kvm_s390_vcpu_sie_inhibited(vcpu)) { + kvm_s390_rewind_psw(vcpu, 4); break; + } } if (rc == -EFAULT) { @@ -978,10 +1378,25 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) scb_s->iprcc = PGM_ADDRESSING; scb_s->pgmilc = 4; scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, 4); + rc = 1; } return rc; } +/* Try getting a given vsie page, returning "true" on success. */ +static inline bool try_get_vsie_page(struct vsie_page *vsie_page) +{ + if (test_bit(VSIE_PAGE_IN_USE, &vsie_page->flags)) + return false; + return !test_and_set_bit(VSIE_PAGE_IN_USE, &vsie_page->flags); +} + +/* Put a vsie page acquired through get_vsie_page / try_get_vsie_page. */ +static void put_vsie_page(struct vsie_page *vsie_page) +{ + clear_bit(VSIE_PAGE_IN_USE, &vsie_page->flags); +} + /* * Get or create a vsie page for a scb address. * @@ -992,16 +1407,21 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) 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); + vsie_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); + if (vsie_page) { + if (try_get_vsie_page(vsie_page)) { + if (vsie_page->scb_gpa == addr) + return vsie_page; + /* + * We raced with someone reusing + putting this vsie + * page before we grabbed it. + */ + put_vsie_page(vsie_page); + } } /* @@ -1012,36 +1432,40 @@ static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr) 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) { + vsie_page = (void *)__get_free_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO | GFP_DMA); + if (!vsie_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; + __set_bit(VSIE_PAGE_IN_USE, &vsie_page->flags); + kvm->arch.vsie.pages[kvm->arch.vsie.page_count] = vsie_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) + vsie_page = kvm->arch.vsie.pages[kvm->arch.vsie.next]; + if (try_get_vsie_page(vsie_page)) 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); + if (vsie_page->scb_gpa != ULONG_MAX) + radix_tree_delete(&kvm->arch.vsie.addr_to_page, + vsie_page->scb_gpa >> 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); + /* Mark it as invalid until it resides in the tree. */ + vsie_page->scb_gpa = ULONG_MAX; + + /* Double use of the same address or allocation failure. */ + if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, + vsie_page)) { + put_vsie_page(vsie_page); mutex_unlock(&kvm->arch.vsie.mutex); return NULL; } + vsie_page->scb_gpa = addr; 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; @@ -1049,14 +1473,6 @@ static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr) 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; @@ -1069,15 +1485,17 @@ int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu) 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); + BUILD_BUG_ON(sizeof(struct vsie_page) != PAGE_SIZE); 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)) + if (kvm_s390_vcpu_has_irq(vcpu, 0) || kvm_s390_vcpu_sie_inhibited(vcpu)) { + kvm_s390_rewind_psw(vcpu, 4); return 0; + } vsie_page = get_vsie_page(vcpu->kvm, scb_addr); if (IS_ERR(vsie_page)) @@ -1104,7 +1522,7 @@ out_unshadow: out_unpin_scb: unpin_scb(vcpu, vsie_page, scb_addr); out_put: - put_vsie_page(vcpu->kvm, vsie_page); + put_vsie_page(vsie_page); return rc < 0 ? rc : 0; } @@ -1113,25 +1531,25 @@ out_put: 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); + INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL_ACCOUNT); } /* 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]; + vsie_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); + if (vsie_page->scb_gpa != ULONG_MAX) + radix_tree_delete(&kvm->arch.vsie.addr_to_page, + vsie_page->scb_gpa >> 9); + free_page((unsigned long)vsie_page); } kvm->arch.vsie.page_count = 0; mutex_unlock(&kvm->arch.vsie.mutex); |