| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * guest access functions |
| * |
| * Copyright IBM Corp. 2014 |
| * |
| */ |
| |
| #include <linux/vmalloc.h> |
| #include <linux/mm_types.h> |
| #include <linux/err.h> |
| #include <linux/pgtable.h> |
| |
| #include <asm/gmap.h> |
| #include "kvm-s390.h" |
| #include "gaccess.h" |
| #include <asm/switch_to.h> |
| |
| union asce { |
| unsigned long val; |
| struct { |
| unsigned long origin : 52; /* Region- or Segment-Table Origin */ |
| unsigned long : 2; |
| unsigned long g : 1; /* Subspace Group Control */ |
| unsigned long p : 1; /* Private Space Control */ |
| unsigned long s : 1; /* Storage-Alteration-Event Control */ |
| unsigned long x : 1; /* Space-Switch-Event Control */ |
| unsigned long r : 1; /* Real-Space Control */ |
| unsigned long : 1; |
| unsigned long dt : 2; /* Designation-Type Control */ |
| unsigned long tl : 2; /* Region- or Segment-Table Length */ |
| }; |
| }; |
| |
| enum { |
| ASCE_TYPE_SEGMENT = 0, |
| ASCE_TYPE_REGION3 = 1, |
| ASCE_TYPE_REGION2 = 2, |
| ASCE_TYPE_REGION1 = 3 |
| }; |
| |
| union region1_table_entry { |
| unsigned long val; |
| struct { |
| unsigned long rto: 52;/* Region-Table Origin */ |
| unsigned long : 2; |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long : 1; |
| unsigned long tf : 2; /* Region-Second-Table Offset */ |
| unsigned long i : 1; /* Region-Invalid Bit */ |
| unsigned long : 1; |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long tl : 2; /* Region-Second-Table Length */ |
| }; |
| }; |
| |
| union region2_table_entry { |
| unsigned long val; |
| struct { |
| unsigned long rto: 52;/* Region-Table Origin */ |
| unsigned long : 2; |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long : 1; |
| unsigned long tf : 2; /* Region-Third-Table Offset */ |
| unsigned long i : 1; /* Region-Invalid Bit */ |
| unsigned long : 1; |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long tl : 2; /* Region-Third-Table Length */ |
| }; |
| }; |
| |
| struct region3_table_entry_fc0 { |
| unsigned long sto: 52;/* Segment-Table Origin */ |
| unsigned long : 1; |
| unsigned long fc : 1; /* Format-Control */ |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long : 1; |
| unsigned long tf : 2; /* Segment-Table Offset */ |
| unsigned long i : 1; /* Region-Invalid Bit */ |
| unsigned long cr : 1; /* Common-Region Bit */ |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long tl : 2; /* Segment-Table Length */ |
| }; |
| |
| struct region3_table_entry_fc1 { |
| unsigned long rfaa : 33; /* Region-Frame Absolute Address */ |
| unsigned long : 14; |
| unsigned long av : 1; /* ACCF-Validity Control */ |
| unsigned long acc: 4; /* Access-Control Bits */ |
| unsigned long f : 1; /* Fetch-Protection Bit */ |
| unsigned long fc : 1; /* Format-Control */ |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long iep: 1; /* Instruction-Execution-Protection */ |
| unsigned long : 2; |
| unsigned long i : 1; /* Region-Invalid Bit */ |
| unsigned long cr : 1; /* Common-Region Bit */ |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long : 2; |
| }; |
| |
| union region3_table_entry { |
| unsigned long val; |
| struct region3_table_entry_fc0 fc0; |
| struct region3_table_entry_fc1 fc1; |
| struct { |
| unsigned long : 53; |
| unsigned long fc : 1; /* Format-Control */ |
| unsigned long : 4; |
| unsigned long i : 1; /* Region-Invalid Bit */ |
| unsigned long cr : 1; /* Common-Region Bit */ |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long : 2; |
| }; |
| }; |
| |
| struct segment_entry_fc0 { |
| unsigned long pto: 53;/* Page-Table Origin */ |
| unsigned long fc : 1; /* Format-Control */ |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long : 3; |
| unsigned long i : 1; /* Segment-Invalid Bit */ |
| unsigned long cs : 1; /* Common-Segment Bit */ |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long : 2; |
| }; |
| |
| struct segment_entry_fc1 { |
| unsigned long sfaa : 44; /* Segment-Frame Absolute Address */ |
| unsigned long : 3; |
| unsigned long av : 1; /* ACCF-Validity Control */ |
| unsigned long acc: 4; /* Access-Control Bits */ |
| unsigned long f : 1; /* Fetch-Protection Bit */ |
| unsigned long fc : 1; /* Format-Control */ |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long iep: 1; /* Instruction-Execution-Protection */ |
| unsigned long : 2; |
| unsigned long i : 1; /* Segment-Invalid Bit */ |
| unsigned long cs : 1; /* Common-Segment Bit */ |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long : 2; |
| }; |
| |
| union segment_table_entry { |
| unsigned long val; |
| struct segment_entry_fc0 fc0; |
| struct segment_entry_fc1 fc1; |
| struct { |
| unsigned long : 53; |
| unsigned long fc : 1; /* Format-Control */ |
| unsigned long : 4; |
| unsigned long i : 1; /* Segment-Invalid Bit */ |
| unsigned long cs : 1; /* Common-Segment Bit */ |
| unsigned long tt : 2; /* Table-Type Bits */ |
| unsigned long : 2; |
| }; |
| }; |
| |
| enum { |
| TABLE_TYPE_SEGMENT = 0, |
| TABLE_TYPE_REGION3 = 1, |
| TABLE_TYPE_REGION2 = 2, |
| TABLE_TYPE_REGION1 = 3 |
| }; |
| |
| union page_table_entry { |
| unsigned long val; |
| struct { |
| unsigned long pfra : 52; /* Page-Frame Real Address */ |
| unsigned long z : 1; /* Zero Bit */ |
| unsigned long i : 1; /* Page-Invalid Bit */ |
| unsigned long p : 1; /* DAT-Protection Bit */ |
| unsigned long iep: 1; /* Instruction-Execution-Protection */ |
| unsigned long : 8; |
| }; |
| }; |
| |
| /* |
| * vaddress union in order to easily decode a virtual address into its |
| * region first index, region second index etc. parts. |
| */ |
| union vaddress { |
| unsigned long addr; |
| struct { |
| unsigned long rfx : 11; |
| unsigned long rsx : 11; |
| unsigned long rtx : 11; |
| unsigned long sx : 11; |
| unsigned long px : 8; |
| unsigned long bx : 12; |
| }; |
| struct { |
| unsigned long rfx01 : 2; |
| unsigned long : 9; |
| unsigned long rsx01 : 2; |
| unsigned long : 9; |
| unsigned long rtx01 : 2; |
| unsigned long : 9; |
| unsigned long sx01 : 2; |
| unsigned long : 29; |
| }; |
| }; |
| |
| /* |
| * raddress union which will contain the result (real or absolute address) |
| * after a page table walk. The rfaa, sfaa and pfra members are used to |
| * simply assign them the value of a region, segment or page table entry. |
| */ |
| union raddress { |
| unsigned long addr; |
| unsigned long rfaa : 33; /* Region-Frame Absolute Address */ |
| unsigned long sfaa : 44; /* Segment-Frame Absolute Address */ |
| unsigned long pfra : 52; /* Page-Frame Real Address */ |
| }; |
| |
| union alet { |
| u32 val; |
| struct { |
| u32 reserved : 7; |
| u32 p : 1; |
| u32 alesn : 8; |
| u32 alen : 16; |
| }; |
| }; |
| |
| union ald { |
| u32 val; |
| struct { |
| u32 : 1; |
| u32 alo : 24; |
| u32 all : 7; |
| }; |
| }; |
| |
| struct ale { |
| unsigned long i : 1; /* ALEN-Invalid Bit */ |
| unsigned long : 5; |
| unsigned long fo : 1; /* Fetch-Only Bit */ |
| unsigned long p : 1; /* Private Bit */ |
| unsigned long alesn : 8; /* Access-List-Entry Sequence Number */ |
| unsigned long aleax : 16; /* Access-List-Entry Authorization Index */ |
| unsigned long : 32; |
| unsigned long : 1; |
| unsigned long asteo : 25; /* ASN-Second-Table-Entry Origin */ |
| unsigned long : 6; |
| unsigned long astesn : 32; /* ASTE Sequence Number */ |
| }; |
| |
| struct aste { |
| unsigned long i : 1; /* ASX-Invalid Bit */ |
| unsigned long ato : 29; /* Authority-Table Origin */ |
| unsigned long : 1; |
| unsigned long b : 1; /* Base-Space Bit */ |
| unsigned long ax : 16; /* Authorization Index */ |
| unsigned long atl : 12; /* Authority-Table Length */ |
| unsigned long : 2; |
| unsigned long ca : 1; /* Controlled-ASN Bit */ |
| unsigned long ra : 1; /* Reusable-ASN Bit */ |
| unsigned long asce : 64; /* Address-Space-Control Element */ |
| unsigned long ald : 32; |
| unsigned long astesn : 32; |
| /* .. more fields there */ |
| }; |
| |
| int ipte_lock_held(struct kvm_vcpu *vcpu) |
| { |
| if (vcpu->arch.sie_block->eca & ECA_SII) { |
| int rc; |
| |
| read_lock(&vcpu->kvm->arch.sca_lock); |
| rc = kvm_s390_get_ipte_control(vcpu->kvm)->kh != 0; |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| return rc; |
| } |
| return vcpu->kvm->arch.ipte_lock_count != 0; |
| } |
| |
| static void ipte_lock_simple(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| mutex_lock(&vcpu->kvm->arch.ipte_mutex); |
| vcpu->kvm->arch.ipte_lock_count++; |
| if (vcpu->kvm->arch.ipte_lock_count > 1) |
| goto out; |
| retry: |
| read_lock(&vcpu->kvm->arch.sca_lock); |
| ic = kvm_s390_get_ipte_control(vcpu->kvm); |
| do { |
| old = READ_ONCE(*ic); |
| if (old.k) { |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| cond_resched(); |
| goto retry; |
| } |
| new = old; |
| new.k = 1; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| out: |
| mutex_unlock(&vcpu->kvm->arch.ipte_mutex); |
| } |
| |
| static void ipte_unlock_simple(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| mutex_lock(&vcpu->kvm->arch.ipte_mutex); |
| vcpu->kvm->arch.ipte_lock_count--; |
| if (vcpu->kvm->arch.ipte_lock_count) |
| goto out; |
| read_lock(&vcpu->kvm->arch.sca_lock); |
| ic = kvm_s390_get_ipte_control(vcpu->kvm); |
| do { |
| old = READ_ONCE(*ic); |
| new = old; |
| new.k = 0; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| wake_up(&vcpu->kvm->arch.ipte_wq); |
| out: |
| mutex_unlock(&vcpu->kvm->arch.ipte_mutex); |
| } |
| |
| static void ipte_lock_siif(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| retry: |
| read_lock(&vcpu->kvm->arch.sca_lock); |
| ic = kvm_s390_get_ipte_control(vcpu->kvm); |
| do { |
| old = READ_ONCE(*ic); |
| if (old.kg) { |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| cond_resched(); |
| goto retry; |
| } |
| new = old; |
| new.k = 1; |
| new.kh++; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| } |
| |
| static void ipte_unlock_siif(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| read_lock(&vcpu->kvm->arch.sca_lock); |
| ic = kvm_s390_get_ipte_control(vcpu->kvm); |
| do { |
| old = READ_ONCE(*ic); |
| new = old; |
| new.kh--; |
| if (!new.kh) |
| new.k = 0; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| read_unlock(&vcpu->kvm->arch.sca_lock); |
| if (!new.kh) |
| wake_up(&vcpu->kvm->arch.ipte_wq); |
| } |
| |
| void ipte_lock(struct kvm_vcpu *vcpu) |
| { |
| if (vcpu->arch.sie_block->eca & ECA_SII) |
| ipte_lock_siif(vcpu); |
| else |
| ipte_lock_simple(vcpu); |
| } |
| |
| void ipte_unlock(struct kvm_vcpu *vcpu) |
| { |
| if (vcpu->arch.sie_block->eca & ECA_SII) |
| ipte_unlock_siif(vcpu); |
| else |
| ipte_unlock_simple(vcpu); |
| } |
| |
| static int ar_translation(struct kvm_vcpu *vcpu, union asce *asce, u8 ar, |
| enum gacc_mode mode) |
| { |
| union alet alet; |
| struct ale ale; |
| struct aste aste; |
| unsigned long ald_addr, authority_table_addr; |
| union ald ald; |
| int eax, rc; |
| u8 authority_table; |
| |
| if (ar >= NUM_ACRS) |
| return -EINVAL; |
| |
| save_access_regs(vcpu->run->s.regs.acrs); |
| alet.val = vcpu->run->s.regs.acrs[ar]; |
| |
| if (ar == 0 || alet.val == 0) { |
| asce->val = vcpu->arch.sie_block->gcr[1]; |
| return 0; |
| } else if (alet.val == 1) { |
| asce->val = vcpu->arch.sie_block->gcr[7]; |
| return 0; |
| } |
| |
| if (alet.reserved) |
| return PGM_ALET_SPECIFICATION; |
| |
| if (alet.p) |
| ald_addr = vcpu->arch.sie_block->gcr[5]; |
| else |
| ald_addr = vcpu->arch.sie_block->gcr[2]; |
| ald_addr &= 0x7fffffc0; |
| |
| rc = read_guest_real(vcpu, ald_addr + 16, &ald.val, sizeof(union ald)); |
| if (rc) |
| return rc; |
| |
| if (alet.alen / 8 > ald.all) |
| return PGM_ALEN_TRANSLATION; |
| |
| if (0x7fffffff - ald.alo * 128 < alet.alen * 16) |
| return PGM_ADDRESSING; |
| |
| rc = read_guest_real(vcpu, ald.alo * 128 + alet.alen * 16, &ale, |
| sizeof(struct ale)); |
| if (rc) |
| return rc; |
| |
| if (ale.i == 1) |
| return PGM_ALEN_TRANSLATION; |
| if (ale.alesn != alet.alesn) |
| return PGM_ALE_SEQUENCE; |
| |
| rc = read_guest_real(vcpu, ale.asteo * 64, &aste, sizeof(struct aste)); |
| if (rc) |
| return rc; |
| |
| if (aste.i) |
| return PGM_ASTE_VALIDITY; |
| if (aste.astesn != ale.astesn) |
| return PGM_ASTE_SEQUENCE; |
| |
| if (ale.p == 1) { |
| eax = (vcpu->arch.sie_block->gcr[8] >> 16) & 0xffff; |
| if (ale.aleax != eax) { |
| if (eax / 16 > aste.atl) |
| return PGM_EXTENDED_AUTHORITY; |
| |
| authority_table_addr = aste.ato * 4 + eax / 4; |
| |
| rc = read_guest_real(vcpu, authority_table_addr, |
| &authority_table, |
| sizeof(u8)); |
| if (rc) |
| return rc; |
| |
| if ((authority_table & (0x40 >> ((eax & 3) * 2))) == 0) |
| return PGM_EXTENDED_AUTHORITY; |
| } |
| } |
| |
| if (ale.fo == 1 && mode == GACC_STORE) |
| return PGM_PROTECTION; |
| |
| asce->val = aste.asce; |
| return 0; |
| } |
| |
| struct trans_exc_code_bits { |
| unsigned long addr : 52; /* Translation-exception Address */ |
| unsigned long fsi : 2; /* Access Exception Fetch/Store Indication */ |
| unsigned long : 2; |
| unsigned long b56 : 1; |
| unsigned long : 3; |
| unsigned long b60 : 1; |
| unsigned long b61 : 1; |
| unsigned long as : 2; /* ASCE Identifier */ |
| }; |
| |
| enum { |
| FSI_UNKNOWN = 0, /* Unknown wether fetch or store */ |
| FSI_STORE = 1, /* Exception was due to store operation */ |
| FSI_FETCH = 2 /* Exception was due to fetch operation */ |
| }; |
| |
| enum prot_type { |
| PROT_TYPE_LA = 0, |
| PROT_TYPE_KEYC = 1, |
| PROT_TYPE_ALC = 2, |
| PROT_TYPE_DAT = 3, |
| PROT_TYPE_IEP = 4, |
| }; |
| |
| static int trans_exc(struct kvm_vcpu *vcpu, int code, unsigned long gva, |
| u8 ar, enum gacc_mode mode, enum prot_type prot) |
| { |
| struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm; |
| struct trans_exc_code_bits *tec; |
| |
| memset(pgm, 0, sizeof(*pgm)); |
| pgm->code = code; |
| tec = (struct trans_exc_code_bits *)&pgm->trans_exc_code; |
| |
| switch (code) { |
| case PGM_PROTECTION: |
| switch (prot) { |
| case PROT_TYPE_IEP: |
| tec->b61 = 1; |
| fallthrough; |
| case PROT_TYPE_LA: |
| tec->b56 = 1; |
| break; |
| case PROT_TYPE_KEYC: |
| tec->b60 = 1; |
| break; |
| case PROT_TYPE_ALC: |
| tec->b60 = 1; |
| fallthrough; |
| case PROT_TYPE_DAT: |
| tec->b61 = 1; |
| break; |
| } |
| fallthrough; |
| 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. |
| */ |
| tec->addr = gva >> PAGE_SHIFT; |
| tec->fsi = mode == GACC_STORE ? FSI_STORE : FSI_FETCH; |
| tec->as = psw_bits(vcpu->arch.sie_block->gpsw).as; |
| fallthrough; |
| case PGM_ALEN_TRANSLATION: |
| case PGM_ALE_SEQUENCE: |
| case PGM_ASTE_VALIDITY: |
| case PGM_ASTE_SEQUENCE: |
| case PGM_EXTENDED_AUTHORITY: |
| /* |
| * We can always store exc_access_id, as it is |
| * undefined for non-ar cases. It is undefined for |
| * most DAT protection exceptions. |
| */ |
| pgm->exc_access_id = ar; |
| break; |
| } |
| return code; |
| } |
| |
| static int get_vcpu_asce(struct kvm_vcpu *vcpu, union asce *asce, |
| unsigned long ga, u8 ar, enum gacc_mode mode) |
| { |
| int rc; |
| struct psw_bits psw = psw_bits(vcpu->arch.sie_block->gpsw); |
| |
| if (!psw.dat) { |
| asce->val = 0; |
| asce->r = 1; |
| return 0; |
| } |
| |
| if ((mode == GACC_IFETCH) && (psw.as != PSW_BITS_AS_HOME)) |
| psw.as = PSW_BITS_AS_PRIMARY; |
| |
| switch (psw.as) { |
| case PSW_BITS_AS_PRIMARY: |
| asce->val = vcpu->arch.sie_block->gcr[1]; |
| return 0; |
| case PSW_BITS_AS_SECONDARY: |
| asce->val = vcpu->arch.sie_block->gcr[7]; |
| return 0; |
| case PSW_BITS_AS_HOME: |
| asce->val = vcpu->arch.sie_block->gcr[13]; |
| return 0; |
| case PSW_BITS_AS_ACCREG: |
| rc = ar_translation(vcpu, asce, ar, mode); |
| if (rc > 0) |
| return trans_exc(vcpu, rc, ga, ar, mode, PROT_TYPE_ALC); |
| return rc; |
| } |
| return 0; |
| } |
| |
| static int deref_table(struct kvm *kvm, unsigned long gpa, unsigned long *val) |
| { |
| return kvm_read_guest(kvm, gpa, val, sizeof(*val)); |
| } |
| |
| /** |
| * guest_translate - translate a guest virtual into a guest absolute address |
| * @vcpu: virtual cpu |
| * @gva: guest virtual address |
| * @gpa: points to where guest physical (absolute) address should be stored |
| * @asce: effective asce |
| * @mode: indicates the access mode to be used |
| * @prot: returns the type for protection exceptions |
| * |
| * Translate a guest virtual address into a guest absolute address by means |
| * of dynamic address translation as specified by the architecture. |
| * If the resulting absolute address is not available in the configuration |
| * an addressing exception is indicated and @gpa will not be changed. |
| * |
| * Returns: - zero on success; @gpa contains the resulting absolute address |
| * - a negative value if guest access failed due to e.g. broken |
| * guest mapping |
| * - a positve value if an access exception happened. In this case |
| * the returned value is the program interruption code as defined |
| * by the architecture |
| */ |
| static unsigned long guest_translate(struct kvm_vcpu *vcpu, unsigned long gva, |
| unsigned long *gpa, const union asce asce, |
| enum gacc_mode mode, enum prot_type *prot) |
| { |
| union vaddress vaddr = {.addr = gva}; |
| union raddress raddr = {.addr = gva}; |
| union page_table_entry pte; |
| int dat_protection = 0; |
| int iep_protection = 0; |
| union ctlreg0 ctlreg0; |
| unsigned long ptr; |
| int edat1, edat2, iep; |
| |
| ctlreg0.val = vcpu->arch.sie_block->gcr[0]; |
| edat1 = ctlreg0.edat && test_kvm_facility(vcpu->kvm, 8); |
| edat2 = edat1 && test_kvm_facility(vcpu->kvm, 78); |
| iep = ctlreg0.iep && test_kvm_facility(vcpu->kvm, 130); |
| if (asce.r) |
| goto real_address; |
| ptr = asce.origin * PAGE_SIZE; |
| switch (asce.dt) { |
| case ASCE_TYPE_REGION1: |
| if (vaddr.rfx01 > asce.tl) |
| return PGM_REGION_FIRST_TRANS; |
| ptr += vaddr.rfx * 8; |
| break; |
| case ASCE_TYPE_REGION2: |
| if (vaddr.rfx) |
| return PGM_ASCE_TYPE; |
| if (vaddr.rsx01 > asce.tl) |
| return PGM_REGION_SECOND_TRANS; |
| ptr += vaddr.rsx * 8; |
| break; |
| case ASCE_TYPE_REGION3: |
| if (vaddr.rfx || vaddr.rsx) |
| return PGM_ASCE_TYPE; |
| if (vaddr.rtx01 > asce.tl) |
| return PGM_REGION_THIRD_TRANS; |
| ptr += vaddr.rtx * 8; |
| 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; |
| ptr += vaddr.sx * 8; |
| break; |
| } |
| switch (asce.dt) { |
| case ASCE_TYPE_REGION1: { |
| union region1_table_entry rfte; |
| |
| if (kvm_is_error_gpa(vcpu->kvm, ptr)) |
| return PGM_ADDRESSING; |
| if (deref_table(vcpu->kvm, ptr, &rfte.val)) |
| return -EFAULT; |
| 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 (edat1) |
| dat_protection |= rfte.p; |
| ptr = rfte.rto * PAGE_SIZE + vaddr.rsx * 8; |
| } |
| fallthrough; |
| case ASCE_TYPE_REGION2: { |
| union region2_table_entry rste; |
| |
| if (kvm_is_error_gpa(vcpu->kvm, ptr)) |
| return PGM_ADDRESSING; |
| if (deref_table(vcpu->kvm, ptr, &rste.val)) |
| return -EFAULT; |
| 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 (edat1) |
| dat_protection |= rste.p; |
| ptr = rste.rto * PAGE_SIZE + vaddr.rtx * 8; |
| } |
| fallthrough; |
| case ASCE_TYPE_REGION3: { |
| union region3_table_entry rtte; |
| |
| if (kvm_is_error_gpa(vcpu->kvm, ptr)) |
| return PGM_ADDRESSING; |
| if (deref_table(vcpu->kvm, ptr, &rtte.val)) |
| return -EFAULT; |
| if (rtte.i) |
| return PGM_REGION_THIRD_TRANS; |
| if (rtte.tt != TABLE_TYPE_REGION3) |
| return PGM_TRANSLATION_SPEC; |
| if (rtte.cr && asce.p && edat2) |
| return PGM_TRANSLATION_SPEC; |
| if (rtte.fc && edat2) { |
| dat_protection |= rtte.fc1.p; |
| iep_protection = rtte.fc1.iep; |
| raddr.rfaa = rtte.fc1.rfaa; |
| goto absolute_address; |
| } |
| if (vaddr.sx01 < rtte.fc0.tf) |
| return PGM_SEGMENT_TRANSLATION; |
| if (vaddr.sx01 > rtte.fc0.tl) |
| return PGM_SEGMENT_TRANSLATION; |
| if (edat1) |
| dat_protection |= rtte.fc0.p; |
| ptr = rtte.fc0.sto * PAGE_SIZE + vaddr.sx * 8; |
| } |
| fallthrough; |
| case ASCE_TYPE_SEGMENT: { |
| union segment_table_entry ste; |
| |
| if (kvm_is_error_gpa(vcpu->kvm, ptr)) |
| return PGM_ADDRESSING; |
| if (deref_table(vcpu->kvm, ptr, &ste.val)) |
| return -EFAULT; |
| 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; |
| if (ste.fc && edat1) { |
| dat_protection |= ste.fc1.p; |
| iep_protection = ste.fc1.iep; |
| raddr.sfaa = ste.fc1.sfaa; |
| goto absolute_address; |
| } |
| dat_protection |= ste.fc0.p; |
| ptr = ste.fc0.pto * (PAGE_SIZE / 2) + vaddr.px * 8; |
| } |
| } |
| if (kvm_is_error_gpa(vcpu->kvm, ptr)) |
| return PGM_ADDRESSING; |
| if (deref_table(vcpu->kvm, ptr, &pte.val)) |
| return -EFAULT; |
| if (pte.i) |
| return PGM_PAGE_TRANSLATION; |
| if (pte.z) |
| return PGM_TRANSLATION_SPEC; |
| dat_protection |= pte.p; |
| iep_protection = pte.iep; |
| raddr.pfra = pte.pfra; |
| real_address: |
| raddr.addr = kvm_s390_real_to_abs(vcpu, raddr.addr); |
| absolute_address: |
| if (mode == GACC_STORE && dat_protection) { |
| *prot = PROT_TYPE_DAT; |
| return PGM_PROTECTION; |
| } |
| if (mode == GACC_IFETCH && iep_protection && iep) { |
| *prot = PROT_TYPE_IEP; |
| return PGM_PROTECTION; |
| } |
| if (kvm_is_error_gpa(vcpu->kvm, raddr.addr)) |
| return PGM_ADDRESSING; |
| *gpa = raddr.addr; |
| return 0; |
| } |
| |
| static inline int is_low_address(unsigned long ga) |
| { |
| /* Check for address ranges 0..511 and 4096..4607 */ |
| return (ga & ~0x11fful) == 0; |
| } |
| |
| static int low_address_protection_enabled(struct kvm_vcpu *vcpu, |
| const union asce asce) |
| { |
| union ctlreg0 ctlreg0 = {.val = vcpu->arch.sie_block->gcr[0]}; |
| psw_t *psw = &vcpu->arch.sie_block->gpsw; |
| |
| if (!ctlreg0.lap) |
| return 0; |
| if (psw_bits(*psw).dat && asce.p) |
| return 0; |
| return 1; |
| } |
| |
| static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, |
| unsigned long *pages, unsigned long nr_pages, |
| const union asce asce, enum gacc_mode mode) |
| { |
| psw_t *psw = &vcpu->arch.sie_block->gpsw; |
| int lap_enabled, rc = 0; |
| enum prot_type prot; |
| |
| lap_enabled = low_address_protection_enabled(vcpu, asce); |
| while (nr_pages) { |
| ga = kvm_s390_logical_to_effective(vcpu, ga); |
| 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).dat) { |
| rc = guest_translate(vcpu, ga, pages, asce, mode, &prot); |
| if (rc < 0) |
| return rc; |
| } else { |
| *pages = kvm_s390_real_to_abs(vcpu, ga); |
| if (kvm_is_error_gpa(vcpu->kvm, *pages)) |
| rc = PGM_ADDRESSING; |
| } |
| if (rc) |
| return trans_exc(vcpu, rc, ga, ar, mode, prot); |
| ga += PAGE_SIZE; |
| pages++; |
| nr_pages--; |
| } |
| return 0; |
| } |
| |
| int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data, |
| unsigned long len, enum gacc_mode mode) |
| { |
| psw_t *psw = &vcpu->arch.sie_block->gpsw; |
| unsigned long _len, nr_pages, gpa, idx; |
| unsigned long pages_array[2]; |
| unsigned long *pages; |
| int need_ipte_lock; |
| union asce asce; |
| int rc; |
| |
| if (!len) |
| return 0; |
| 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; |
| pages = pages_array; |
| if (nr_pages > ARRAY_SIZE(pages_array)) |
| pages = vmalloc(array_size(nr_pages, sizeof(unsigned long))); |
| if (!pages) |
| return -ENOMEM; |
| need_ipte_lock = psw_bits(*psw).dat && !asce.r; |
| if (need_ipte_lock) |
| ipte_lock(vcpu); |
| 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); |
| if (mode == GACC_STORE) |
| rc = kvm_write_guest(vcpu->kvm, gpa, data, _len); |
| else |
| rc = kvm_read_guest(vcpu->kvm, gpa, data, _len); |
| len -= _len; |
| ga += _len; |
| data += _len; |
| } |
| if (need_ipte_lock) |
| ipte_unlock(vcpu); |
| if (nr_pages > ARRAY_SIZE(pages_array)) |
| vfree(pages); |
| return rc; |
| } |
| |
| int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, |
| void *data, unsigned long len, enum gacc_mode mode) |
| { |
| unsigned long _len, gpa; |
| int rc = 0; |
| |
| while (len && !rc) { |
| gpa = kvm_s390_real_to_abs(vcpu, gra); |
| _len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len); |
| if (mode) |
| rc = write_guest_abs(vcpu, gpa, data, _len); |
| else |
| rc = read_guest_abs(vcpu, gpa, data, _len); |
| len -= _len; |
| gra += _len; |
| data += _len; |
| } |
| return rc; |
| } |
| |
| /** |
| * guest_translate_address - translate guest logical into guest absolute address |
| * @vcpu: virtual cpu |
| * @gva: Guest virtual address |
| * @ar: Access register |
| * @gpa: Guest physical address |
| * @mode: Translation access mode |
| * |
| * Parameter semantics are the same as the ones from guest_translate. |
| * The memory contents at the guest address are not changed. |
| * |
| * Note: The IPTE lock is not taken during this function, so the caller |
| * has to take care of this. |
| */ |
| int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva, u8 ar, |
| unsigned long *gpa, enum gacc_mode mode) |
| { |
| psw_t *psw = &vcpu->arch.sie_block->gpsw; |
| enum prot_type prot; |
| union asce asce; |
| int rc; |
| |
| gva = kvm_s390_logical_to_effective(vcpu, gva); |
| 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) |
| return trans_exc(vcpu, PGM_PROTECTION, gva, 0, |
| mode, PROT_TYPE_LA); |
| } |
| |
| if (psw_bits(*psw).dat && !asce.r) { /* Use DAT? */ |
| rc = guest_translate(vcpu, gva, gpa, asce, mode, &prot); |
| if (rc > 0) |
| return trans_exc(vcpu, rc, gva, 0, mode, prot); |
| } else { |
| *gpa = kvm_s390_real_to_abs(vcpu, gva); |
| if (kvm_is_error_gpa(vcpu->kvm, *gpa)) |
| return trans_exc(vcpu, rc, gva, PGM_ADDRESSING, mode, 0); |
| } |
| |
| return rc; |
| } |
| |
| /** |
| * check_gva_range - test a range of guest virtual addresses for accessibility |
| * @vcpu: virtual cpu |
| * @gva: Guest virtual address |
| * @ar: Access register |
| * @length: Length of test range |
| * @mode: Translation access mode |
| */ |
| int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, u8 ar, |
| unsigned long length, enum gacc_mode mode) |
| { |
| unsigned long gpa; |
| unsigned long currlen; |
| int rc = 0; |
| |
| ipte_lock(vcpu); |
| while (length > 0 && !rc) { |
| currlen = min(length, PAGE_SIZE - (gva % PAGE_SIZE)); |
| rc = guest_translate_address(vcpu, gva, ar, &gpa, mode); |
| gva += currlen; |
| length -= currlen; |
| } |
| ipte_unlock(vcpu); |
| |
| return rc; |
| } |
| |
| /** |
| * kvm_s390_check_low_addr_prot_real - check for low-address protection |
| * @vcpu: virtual cpu |
| * @gra: Guest real address |
| * |
| * Checks whether an address is subject to low-address protection and set |
| * up vcpu->arch.pgm accordingly if necessary. |
| * |
| * Return: 0 if no protection exception, or PGM_PROTECTION if protected. |
| */ |
| int kvm_s390_check_low_addr_prot_real(struct kvm_vcpu *vcpu, unsigned long gra) |
| { |
| 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); |
| } |
| |
| /** |
| * 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 beginning of the page table for the given address if |
| * successful (return value 0), or to the first invalid DAT entry in |
| * case of exceptions (return value > 0) |
| * @dat_protection: referenced memory is write protected |
| * @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 * PAGE_SIZE; |
| if (asce.r) { |
| *fake = 1; |
| ptr = 0; |
| asce.dt = ASCE_TYPE_REGION1; |
| } |
| switch (asce.dt) { |
| case ASCE_TYPE_REGION1: |
| if (vaddr.rfx01 > asce.tl && !*fake) |
| 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) { |
| ptr += vaddr.rfx * _REGION1_SIZE; |
| rfte.val = ptr; |
| goto shadow_r2t; |
| } |
| *pgt = ptr + vaddr.rfx * 8; |
| 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 * PAGE_SIZE; |
| 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) { |
| ptr += vaddr.rsx * _REGION2_SIZE; |
| rste.val = ptr; |
| goto shadow_r3t; |
| } |
| *pgt = ptr + vaddr.rsx * 8; |
| 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 * PAGE_SIZE; |
| 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) { |
| ptr += vaddr.rtx * _REGION3_SIZE; |
| rtte.val = ptr; |
| goto shadow_sgt; |
| } |
| *pgt = ptr + vaddr.rtx * 8; |
| 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 * _REGION3_SIZE; |
| 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 * PAGE_SIZE; |
| 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) { |
| ptr += vaddr.sx * _SEGMENT_SIZE; |
| ste.val = ptr; |
| goto shadow_pgt; |
| } |
| *pgt = ptr + vaddr.sx * 8; |
| 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 * _SEGMENT_SIZE; |
| ste.val = ptr; |
| goto shadow_pgt; |
| } |
| ptr = ste.fc0.pto * (PAGE_SIZE / 2); |
| 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 |
| * @datptr: will contain the address of the faulting DAT table entry, or of |
| * the valid leaf, plus some flags |
| * |
| * 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, unsigned long *datptr) |
| { |
| union vaddress vaddr; |
| union page_table_entry pte; |
| unsigned long pgt = 0; |
| int dat_protection, fake; |
| int rc; |
| |
| mmap_read_lock(sg->mm); |
| /* |
| * 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) { |
| pte.val = pgt + vaddr.px * PAGE_SIZE; |
| goto shadow_page; |
| } |
| |
| switch (rc) { |
| case PGM_SEGMENT_TRANSLATION: |
| case PGM_REGION_THIRD_TRANS: |
| case PGM_REGION_SECOND_TRANS: |
| case PGM_REGION_FIRST_TRANS: |
| pgt |= PEI_NOT_PTE; |
| break; |
| case 0: |
| pgt += vaddr.px * 8; |
| rc = gmap_read_table(sg->parent, pgt, &pte.val); |
| } |
| if (datptr) |
| *datptr = pgt | dat_protection * PEI_DAT_PROT; |
| if (!rc && pte.i) |
| rc = PGM_PAGE_TRANSLATION; |
| if (!rc && pte.z) |
| rc = PGM_TRANSLATION_SPEC; |
| shadow_page: |
| pte.p |= dat_protection; |
| if (!rc) |
| rc = gmap_shadow_page(sg, saddr, __pte(pte.val)); |
| ipte_unlock(vcpu); |
| mmap_read_unlock(sg->mm); |
| return rc; |
| } |
