diff options
Diffstat (limited to 'arch/s390/kvm/gaccess.c')
| -rw-r--r-- | arch/s390/kvm/gaccess.c | 387 |
1 files changed, 320 insertions, 67 deletions
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 66938d283..54200208b 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> @@ -476,18 +477,73 @@ enum { FSI_FETCH = 2 /* Exception was due to fetch operation */ }; -static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce, - ar_t ar, enum gacc_mode mode) +enum prot_type { + PROT_TYPE_LA = 0, + PROT_TYPE_KEYC = 1, + PROT_TYPE_ALC = 2, + PROT_TYPE_DAT = 3, +}; + +static int trans_exc(struct kvm_vcpu *vcpu, int code, unsigned long gva, + ar_t ar, enum gacc_mode mode, enum prot_type prot) { - int rc; - struct psw_bits psw = psw_bits(vcpu->arch.sie_block->gpsw); struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm; - struct trans_exc_code_bits *tec_bits; + struct trans_exc_code_bits *tec; memset(pgm, 0, sizeof(*pgm)); - tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code; - tec_bits->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH; - tec_bits->as = psw.as; + pgm->code = code; + tec = (struct trans_exc_code_bits *)&pgm->trans_exc_code; + + switch (code) { + case PGM_ASCE_TYPE: + case PGM_PAGE_TRANSLATION: + case PGM_REGION_FIRST_TRANS: + case PGM_REGION_SECOND_TRANS: + case PGM_REGION_THIRD_TRANS: + case PGM_SEGMENT_TRANSLATION: + /* + * op_access_id only applies to MOVE_PAGE -> set bit 61 + * exc_access_id has to be set to 0 for some instructions. Both + * cases have to be handled by the caller. We can always store + * exc_access_id, as it is undefined for non-ar cases. + */ + tec->addr = gva >> PAGE_SHIFT; + tec->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH; + tec->as = psw_bits(vcpu->arch.sie_block->gpsw).as; + /* FALL THROUGH */ + case PGM_ALEN_TRANSLATION: + case PGM_ALE_SEQUENCE: + case PGM_ASTE_VALIDITY: + case PGM_ASTE_SEQUENCE: + case PGM_EXTENDED_AUTHORITY: + pgm->exc_access_id = ar; + break; + case PGM_PROTECTION: + switch (prot) { + case PROT_TYPE_ALC: + tec->b60 = 1; + /* FALL THROUGH */ + case PROT_TYPE_DAT: + tec->b61 = 1; + tec->addr = gva >> PAGE_SHIFT; + tec->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH; + tec->as = psw_bits(vcpu->arch.sie_block->gpsw).as; + /* exc_access_id is undefined for most cases */ + pgm->exc_access_id = ar; + break; + default: /* LA and KEYC set b61 to 0, other params undefined */ + break; + } + break; + } + return code; +} + +static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce, + unsigned long ga, ar_t ar, enum gacc_mode mode) +{ + int rc; + struct psw_bits psw = psw_bits(vcpu->arch.sie_block->gpsw); if (!psw.t) { asce->val = 0; @@ -510,21 +566,8 @@ static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce, return 0; case PSW_AS_ACCREG: rc = ar_translation(vcpu, asce, ar, mode); - switch (rc) { - case PGM_ALEN_TRANSLATION: - case PGM_ALE_SEQUENCE: - case PGM_ASTE_VALIDITY: - case PGM_ASTE_SEQUENCE: - case PGM_EXTENDED_AUTHORITY: - vcpu->arch.pgm.exc_access_id = ar; - break; - case PGM_PROTECTION: - tec_bits->b60 = 1; - tec_bits->b61 = 1; - break; - } if (rc > 0) - pgm->code = rc; + return trans_exc(vcpu, rc, ga, ar, mode, PROT_TYPE_ALC); return rc; } return 0; @@ -729,40 +772,31 @@ static int low_address_protection_enabled(struct kvm_vcpu *vcpu, return 1; } -static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga, +static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar, unsigned long *pages, unsigned long nr_pages, const union asce asce, enum gacc_mode mode) { - struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm; psw_t *psw = &vcpu->arch.sie_block->gpsw; - struct trans_exc_code_bits *tec_bits; - int lap_enabled, rc; + int lap_enabled, rc = 0; - tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code; lap_enabled = low_address_protection_enabled(vcpu, asce); while (nr_pages) { ga = kvm_s390_logical_to_effective(vcpu, ga); - tec_bits->addr = ga >> PAGE_SHIFT; - if (mode == GACC_STORE && lap_enabled && is_low_address(ga)) { - pgm->code = PGM_PROTECTION; - return pgm->code; - } + if (mode == GACC_STORE && lap_enabled && is_low_address(ga)) + return trans_exc(vcpu, PGM_PROTECTION, ga, ar, mode, + PROT_TYPE_LA); ga &= PAGE_MASK; if (psw_bits(*psw).t) { rc = guest_translate(vcpu, ga, pages, asce, mode); if (rc < 0) return rc; - if (rc == PGM_PROTECTION) - tec_bits->b61 = 1; - if (rc) - pgm->code = rc; } else { *pages = kvm_s390_real_to_abs(vcpu, ga); if (kvm_is_error_gpa(vcpu->kvm, *pages)) - pgm->code = PGM_ADDRESSING; + rc = PGM_ADDRESSING; } - if (pgm->code) - return pgm->code; + if (rc) + return trans_exc(vcpu, rc, ga, ar, mode, PROT_TYPE_DAT); ga += PAGE_SIZE; pages++; nr_pages--; @@ -783,7 +817,8 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar, void *data, if (!len) return 0; - rc = get_vcpu_asce(vcpu, &asce, ar, mode); + ga = kvm_s390_logical_to_effective(vcpu, ga); + rc = get_vcpu_asce(vcpu, &asce, ga, ar, mode); if (rc) return rc; nr_pages = (((ga & ~PAGE_MASK) + len - 1) >> PAGE_SHIFT) + 1; @@ -795,7 +830,7 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, ar_t ar, void *data, need_ipte_lock = psw_bits(*psw).t && !asce.r; if (need_ipte_lock) ipte_lock(vcpu); - rc = guest_page_range(vcpu, ga, pages, nr_pages, asce, mode); + rc = guest_page_range(vcpu, ga, ar, pages, nr_pages, asce, mode); for (idx = 0; idx < nr_pages && !rc; idx++) { gpa = *(pages + idx) + (ga & ~PAGE_MASK); _len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len); @@ -846,37 +881,28 @@ int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva, ar_t ar, unsigned long *gpa, enum gacc_mode mode) { - struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm; psw_t *psw = &vcpu->arch.sie_block->gpsw; - struct trans_exc_code_bits *tec; union asce asce; int rc; gva = kvm_s390_logical_to_effective(vcpu, gva); - tec = (struct trans_exc_code_bits *)&pgm->trans_exc_code; - rc = get_vcpu_asce(vcpu, &asce, ar, mode); - tec->addr = gva >> PAGE_SHIFT; + rc = get_vcpu_asce(vcpu, &asce, gva, ar, mode); if (rc) return rc; if (is_low_address(gva) && low_address_protection_enabled(vcpu, asce)) { - if (mode == GACC_STORE) { - rc = pgm->code = PGM_PROTECTION; - return rc; - } + if (mode == GACC_STORE) + return trans_exc(vcpu, PGM_PROTECTION, gva, 0, + mode, PROT_TYPE_LA); } if (psw_bits(*psw).t && !asce.r) { /* Use DAT? */ rc = guest_translate(vcpu, gva, gpa, asce, mode); - if (rc > 0) { - if (rc == PGM_PROTECTION) - tec->b61 = 1; - pgm->code = rc; - } + if (rc > 0) + return trans_exc(vcpu, rc, gva, 0, mode, PROT_TYPE_DAT); } else { - rc = 0; *gpa = kvm_s390_real_to_abs(vcpu, gva); if (kvm_is_error_gpa(vcpu->kvm, *gpa)) - rc = pgm->code = PGM_ADDRESSING; + return trans_exc(vcpu, rc, gva, PGM_ADDRESSING, mode, 0); } return rc; @@ -915,20 +941,247 @@ int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, ar_t ar, */ int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra) { - struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm; - psw_t *psw = &vcpu->arch.sie_block->gpsw; - struct trans_exc_code_bits *tec_bits; union ctlreg0 ctlreg0 = {.val = vcpu->arch.sie_block->gcr[0]}; if (!ctlreg0.lap || !is_low_address(gra)) return 0; + return trans_exc(vcpu, PGM_PROTECTION, gra, 0, GACC_STORE, PROT_TYPE_LA); +} - memset(pgm, 0, sizeof(*pgm)); - tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code; - tec_bits->fsi = FSI_STORE; - tec_bits->as = psw_bits(*psw).as; - tec_bits->addr = gra >> PAGE_SHIFT; - pgm->code = PGM_PROTECTION; +/** + * 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; - return pgm->code; + 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; } |