| /* |
| * guest access functions |
| * |
| * Copyright IBM Corp. 2014 |
| * |
| */ |
| |
| #include <linux/vmalloc.h> |
| #include <linux/err.h> |
| #include <asm/pgtable.h> |
| #include "kvm-s390.h" |
| #include "gaccess.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 co : 1; /* Change-Recording Override */ |
| 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 co : 1; /* Change-Recording Override */ |
| 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 co : 1; /* Change-Recording Override */ |
| 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 */ |
| }; |
| |
| static int ipte_lock_count; |
| static DEFINE_MUTEX(ipte_mutex); |
| |
| int ipte_lock_held(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control *ic = &vcpu->kvm->arch.sca->ipte_control; |
| |
| if (vcpu->arch.sie_block->eca & 1) |
| return ic->kh != 0; |
| return ipte_lock_count != 0; |
| } |
| |
| static void ipte_lock_simple(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| mutex_lock(&ipte_mutex); |
| ipte_lock_count++; |
| if (ipte_lock_count > 1) |
| goto out; |
| ic = &vcpu->kvm->arch.sca->ipte_control; |
| do { |
| old = ACCESS_ONCE(*ic); |
| while (old.k) { |
| cond_resched(); |
| old = ACCESS_ONCE(*ic); |
| } |
| new = old; |
| new.k = 1; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| out: |
| mutex_unlock(&ipte_mutex); |
| } |
| |
| static void ipte_unlock_simple(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| mutex_lock(&ipte_mutex); |
| ipte_lock_count--; |
| if (ipte_lock_count) |
| goto out; |
| ic = &vcpu->kvm->arch.sca->ipte_control; |
| do { |
| new = old = ACCESS_ONCE(*ic); |
| new.k = 0; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| if (!ipte_lock_count) |
| wake_up(&vcpu->kvm->arch.ipte_wq); |
| out: |
| mutex_unlock(&ipte_mutex); |
| } |
| |
| static void ipte_lock_siif(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| ic = &vcpu->kvm->arch.sca->ipte_control; |
| do { |
| old = ACCESS_ONCE(*ic); |
| while (old.kg) { |
| cond_resched(); |
| old = ACCESS_ONCE(*ic); |
| } |
| new = old; |
| new.k = 1; |
| new.kh++; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| } |
| |
| static void ipte_unlock_siif(struct kvm_vcpu *vcpu) |
| { |
| union ipte_control old, new, *ic; |
| |
| ic = &vcpu->kvm->arch.sca->ipte_control; |
| do { |
| new = old = ACCESS_ONCE(*ic); |
| new.kh--; |
| if (!new.kh) |
| new.k = 0; |
| } while (cmpxchg(&ic->val, old.val, new.val) != old.val); |
| if (!new.kh) |
| wake_up(&vcpu->kvm->arch.ipte_wq); |
| } |
| |
| static void ipte_lock(struct kvm_vcpu *vcpu) |
| { |
| if (vcpu->arch.sie_block->eca & 1) |
| ipte_lock_siif(vcpu); |
| else |
| ipte_lock_simple(vcpu); |
| } |
| |
| static void ipte_unlock(struct kvm_vcpu *vcpu) |
| { |
| if (vcpu->arch.sie_block->eca & 1) |
| ipte_unlock_siif(vcpu); |
| else |
| ipte_unlock_simple(vcpu); |
| } |
| |
| static unsigned long get_vcpu_asce(struct kvm_vcpu *vcpu) |
| { |
| switch (psw_bits(vcpu->arch.sie_block->gpsw).as) { |
| case PSW_AS_PRIMARY: |
| return vcpu->arch.sie_block->gcr[1]; |
| case PSW_AS_SECONDARY: |
| return vcpu->arch.sie_block->gcr[7]; |
| case PSW_AS_HOME: |
| return vcpu->arch.sie_block->gcr[13]; |
| } |
| 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 |
| * @write: indicates if access is a write access |
| * |
| * Translate a guest virtual address into a guest absolute address by means |
| * of dynamic address translation as specified by the architecuture. |
| * 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, int write) |
| { |
| union vaddress vaddr = {.addr = gva}; |
| union raddress raddr = {.addr = gva}; |
| union page_table_entry pte; |
| int dat_protection = 0; |
| union ctlreg0 ctlreg0; |
| unsigned long ptr; |
| int edat1, edat2; |
| union asce asce; |
| |
| ctlreg0.val = vcpu->arch.sie_block->gcr[0]; |
| edat1 = ctlreg0.edat && test_vfacility(8); |
| edat2 = edat1 && test_vfacility(78); |
| asce.val = get_vcpu_asce(vcpu); |
| if (asce.r) |
| goto real_address; |
| ptr = asce.origin * 4096; |
| 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 * 4096 + 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 * 4096 + 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; |
| 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 * 4096 + 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; |
| raddr.sfaa = ste.fc1.sfaa; |
| goto absolute_address; |
| } |
| dat_protection |= ste.fc0.p; |
| ptr = ste.fc0.pto * 2048 + 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; |
| if (pte.co && !edat1) |
| return PGM_TRANSLATION_SPEC; |
| dat_protection |= pte.p; |
| raddr.pfra = pte.pfra; |
| real_address: |
| raddr.addr = kvm_s390_real_to_abs(vcpu, raddr.addr); |
| absolute_address: |
| if (write && dat_protection) |
| 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) |
| { |
| union ctlreg0 ctlreg0 = {.val = vcpu->arch.sie_block->gcr[0]}; |
| psw_t *psw = &vcpu->arch.sie_block->gpsw; |
| union asce asce; |
| |
| if (!ctlreg0.lap) |
| return 0; |
| asce.val = get_vcpu_asce(vcpu); |
| if (psw_bits(*psw).t && asce.p) |
| return 0; |
| return 1; |
| } |
| |
| struct trans_exc_code_bits { |
| unsigned long addr : 52; /* Translation-exception Address */ |
| unsigned long fsi : 2; /* Access Exception Fetch/Store Indication */ |
| unsigned long : 7; |
| 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 */ |
| }; |
| |
| static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga, |
| unsigned long *pages, unsigned long nr_pages, |
| int write) |
| { |
| 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; |
| |
| memset(pgm, 0, sizeof(*pgm)); |
| tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code; |
| tec_bits->fsi = write ? FSI_STORE : FSI_FETCH; |
| tec_bits->as = psw_bits(*psw).as; |
| lap_enabled = low_address_protection_enabled(vcpu); |
| while (nr_pages) { |
| ga = kvm_s390_logical_to_effective(vcpu, ga); |
| tec_bits->addr = ga >> PAGE_SHIFT; |
| if (write && lap_enabled && is_low_address(ga)) { |
| pgm->code = PGM_PROTECTION; |
| return pgm->code; |
| } |
| ga &= PAGE_MASK; |
| if (psw_bits(*psw).t) { |
| rc = guest_translate(vcpu, ga, pages, write); |
| 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; |
| } |
| if (pgm->code) |
| return pgm->code; |
| ga += PAGE_SIZE; |
| pages++; |
| nr_pages--; |
| } |
| return 0; |
| } |
| |
| int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, void *data, |
| unsigned long len, int write) |
| { |
| 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; |
| /* Access register mode is not supported yet. */ |
| if (psw_bits(*psw).t && psw_bits(*psw).as == PSW_AS_ACCREG) |
| return -EOPNOTSUPP; |
| nr_pages = (((ga & ~PAGE_MASK) + len - 1) >> PAGE_SHIFT) + 1; |
| pages = pages_array; |
| if (nr_pages > ARRAY_SIZE(pages_array)) |
| pages = vmalloc(nr_pages * sizeof(unsigned long)); |
| if (!pages) |
| return -ENOMEM; |
| asce.val = get_vcpu_asce(vcpu); |
| 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, write); |
| for (idx = 0; idx < nr_pages && !rc; idx++) { |
| gpa = *(pages + idx) + (ga & ~PAGE_MASK); |
| _len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len); |
| if (write) |
| 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, int write) |
| { |
| 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 (write) |
| 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; |
| } |