diff options
author | Janosch Frank <frankja@linux.ibm.com> | 2018-07-31 00:20:00 +0300 |
---|---|---|
committer | Janosch Frank <frankja@linux.ibm.com> | 2018-07-31 00:20:48 +0300 |
commit | 2375846193663a1282c0ef7093640ed3210dc09f (patch) | |
tree | 8f8a434b5475eed580308753adba5cd999274e7c /arch/s390/kvm | |
parent | 57cb198cfdd2e666a8dc2b7e5df6d2708191eddb (diff) | |
parent | a449938297e55e7e8958f8b48583f7d342da1930 (diff) | |
download | linux-2375846193663a1282c0ef7093640ed3210dc09f.tar.xz |
Merge tag 'hlp_stage1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvms390/next
KVM: s390: initial host large page support
- must be enabled via module parameter hpage=1
- cannot be used together with nested
- does support migration
- does support hugetlbfs
- no THP yet
Diffstat (limited to 'arch/s390/kvm')
-rw-r--r-- | arch/s390/kvm/kvm-s390.c | 82 | ||||
-rw-r--r-- | arch/s390/kvm/priv.c | 103 |
2 files changed, 140 insertions, 45 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 0cc8a48fc732..91ad4a9425c0 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -172,6 +172,10 @@ static int nested; module_param(nested, int, S_IRUGO); MODULE_PARM_DESC(nested, "Nested virtualization support"); +/* allow 1m huge page guest backing, if !nested */ +static int hpage; +module_param(hpage, int, 0444); +MODULE_PARM_DESC(hpage, "1m huge page backing support"); /* * For now we handle at most 16 double words as this is what the s390 base @@ -475,6 +479,11 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_S390_AIS_MIGRATION: r = 1; break; + case KVM_CAP_S390_HPAGE_1M: + r = 0; + if (hpage) + r = 1; + break; case KVM_CAP_S390_MEM_OP: r = MEM_OP_MAX_SIZE; break; @@ -511,19 +520,30 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) } static void kvm_s390_sync_dirty_log(struct kvm *kvm, - struct kvm_memory_slot *memslot) + struct kvm_memory_slot *memslot) { + int i; gfn_t cur_gfn, last_gfn; - unsigned long address; + unsigned long gaddr, vmaddr; struct gmap *gmap = kvm->arch.gmap; + DECLARE_BITMAP(bitmap, _PAGE_ENTRIES); - /* Loop over all guest pages */ + /* Loop over all guest segments */ + cur_gfn = memslot->base_gfn; last_gfn = memslot->base_gfn + memslot->npages; - for (cur_gfn = memslot->base_gfn; cur_gfn <= last_gfn; cur_gfn++) { - address = gfn_to_hva_memslot(memslot, cur_gfn); + for (; cur_gfn <= last_gfn; cur_gfn += _PAGE_ENTRIES) { + gaddr = gfn_to_gpa(cur_gfn); + vmaddr = gfn_to_hva_memslot(memslot, cur_gfn); + if (kvm_is_error_hva(vmaddr)) + continue; + + bitmap_zero(bitmap, _PAGE_ENTRIES); + gmap_sync_dirty_log_pmd(gmap, bitmap, gaddr, vmaddr); + for (i = 0; i < _PAGE_ENTRIES; i++) { + if (test_bit(i, bitmap)) + mark_page_dirty(kvm, cur_gfn + i); + } - if (test_and_clear_guest_dirty(gmap->mm, address)) - mark_page_dirty(kvm, cur_gfn); if (fatal_signal_pending(current)) return; cond_resched(); @@ -667,6 +687,27 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) VM_EVENT(kvm, 3, "ENABLE: CAP_S390_GS %s", r ? "(not available)" : "(success)"); break; + case KVM_CAP_S390_HPAGE_1M: + mutex_lock(&kvm->lock); + if (kvm->created_vcpus) + r = -EBUSY; + else if (!hpage || kvm->arch.use_cmma) + r = -EINVAL; + else { + r = 0; + kvm->mm->context.allow_gmap_hpage_1m = 1; + /* + * We might have to create fake 4k page + * tables. To avoid that the hardware works on + * stale PGSTEs, we emulate these instructions. + */ + kvm->arch.use_skf = 0; + kvm->arch.use_pfmfi = 0; + } + mutex_unlock(&kvm->lock); + VM_EVENT(kvm, 3, "ENABLE: CAP_S390_HPAGE %s", + r ? "(not available)" : "(success)"); + break; case KVM_CAP_S390_USER_STSI: VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_STSI"); kvm->arch.user_stsi = 1; @@ -714,10 +755,13 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att if (!sclp.has_cmma) break; - ret = -EBUSY; VM_EVENT(kvm, 3, "%s", "ENABLE: CMMA support"); mutex_lock(&kvm->lock); - if (!kvm->created_vcpus) { + if (kvm->created_vcpus) + ret = -EBUSY; + else if (kvm->mm->context.allow_gmap_hpage_1m) + ret = -EINVAL; + else { kvm->arch.use_cmma = 1; /* Not compatible with cmma. */ kvm->arch.use_pfmfi = 0; @@ -1514,6 +1558,7 @@ static long kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) uint8_t *keys; uint64_t hva; int srcu_idx, i, r = 0; + bool unlocked; if (args->flags != 0) return -EINVAL; @@ -1538,9 +1583,11 @@ static long kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) if (r) goto out; + i = 0; down_read(¤t->mm->mmap_sem); srcu_idx = srcu_read_lock(&kvm->srcu); - for (i = 0; i < args->count; i++) { + while (i < args->count) { + unlocked = false; hva = gfn_to_hva(kvm, args->start_gfn + i); if (kvm_is_error_hva(hva)) { r = -EFAULT; @@ -1554,8 +1601,14 @@ static long kvm_s390_set_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) } r = set_guest_storage_key(current->mm, hva, keys[i], 0); - if (r) - break; + if (r) { + r = fixup_user_fault(current, current->mm, hva, + FAULT_FLAG_WRITE, &unlocked); + if (r) + break; + } + if (!r) + i++; } srcu_read_unlock(&kvm->srcu, srcu_idx); up_read(¤t->mm->mmap_sem); @@ -4141,6 +4194,11 @@ static int __init kvm_s390_init(void) return -ENODEV; } + if (nested && hpage) { + pr_info("nested (vSIE) and hpage (huge page backing) can currently not be activated concurrently"); + return -EINVAL; + } + for (i = 0; i < 16; i++) kvm_s390_fac_base[i] |= S390_lowcore.stfle_fac_list[i] & nonhyp_mask(i); diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 63285b14ff31..d68f10441a16 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -244,9 +244,10 @@ static int try_handle_skey(struct kvm_vcpu *vcpu) static int handle_iske(struct kvm_vcpu *vcpu) { - unsigned long addr; + unsigned long gaddr, vmaddr; unsigned char key; int reg1, reg2; + bool unlocked; int rc; vcpu->stat.instruction_iske++; @@ -260,18 +261,28 @@ static int handle_iske(struct kvm_vcpu *vcpu) kvm_s390_get_regs_rre(vcpu, ®1, ®2); - addr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK; - addr = kvm_s390_logical_to_effective(vcpu, addr); - addr = kvm_s390_real_to_abs(vcpu, addr); - addr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(addr)); - if (kvm_is_error_hva(addr)) + gaddr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK; + gaddr = kvm_s390_logical_to_effective(vcpu, gaddr); + gaddr = kvm_s390_real_to_abs(vcpu, gaddr); + vmaddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(gaddr)); + if (kvm_is_error_hva(vmaddr)) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - +retry: + unlocked = false; down_read(¤t->mm->mmap_sem); - rc = get_guest_storage_key(current->mm, addr, &key); - up_read(¤t->mm->mmap_sem); + rc = get_guest_storage_key(current->mm, vmaddr, &key); + + if (rc) { + rc = fixup_user_fault(current, current->mm, vmaddr, + FAULT_FLAG_WRITE, &unlocked); + if (!rc) { + up_read(¤t->mm->mmap_sem); + goto retry; + } + } if (rc) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); + up_read(¤t->mm->mmap_sem); vcpu->run->s.regs.gprs[reg1] &= ~0xff; vcpu->run->s.regs.gprs[reg1] |= key; return 0; @@ -279,8 +290,9 @@ static int handle_iske(struct kvm_vcpu *vcpu) static int handle_rrbe(struct kvm_vcpu *vcpu) { - unsigned long addr; + unsigned long vmaddr, gaddr; int reg1, reg2; + bool unlocked; int rc; vcpu->stat.instruction_rrbe++; @@ -294,19 +306,27 @@ static int handle_rrbe(struct kvm_vcpu *vcpu) kvm_s390_get_regs_rre(vcpu, ®1, ®2); - addr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK; - addr = kvm_s390_logical_to_effective(vcpu, addr); - addr = kvm_s390_real_to_abs(vcpu, addr); - addr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(addr)); - if (kvm_is_error_hva(addr)) + gaddr = vcpu->run->s.regs.gprs[reg2] & PAGE_MASK; + gaddr = kvm_s390_logical_to_effective(vcpu, gaddr); + gaddr = kvm_s390_real_to_abs(vcpu, gaddr); + vmaddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(gaddr)); + if (kvm_is_error_hva(vmaddr)) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - +retry: + unlocked = false; down_read(¤t->mm->mmap_sem); - rc = reset_guest_reference_bit(current->mm, addr); - up_read(¤t->mm->mmap_sem); + rc = reset_guest_reference_bit(current->mm, vmaddr); + if (rc < 0) { + rc = fixup_user_fault(current, current->mm, vmaddr, + FAULT_FLAG_WRITE, &unlocked); + if (!rc) { + up_read(¤t->mm->mmap_sem); + goto retry; + } + } if (rc < 0) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - + up_read(¤t->mm->mmap_sem); kvm_s390_set_psw_cc(vcpu, rc); return 0; } @@ -321,6 +341,7 @@ static int handle_sske(struct kvm_vcpu *vcpu) unsigned long start, end; unsigned char key, oldkey; int reg1, reg2; + bool unlocked; int rc; vcpu->stat.instruction_sske++; @@ -353,19 +374,28 @@ static int handle_sske(struct kvm_vcpu *vcpu) } while (start != end) { - unsigned long addr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(start)); + unsigned long vmaddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(start)); + unlocked = false; - if (kvm_is_error_hva(addr)) + if (kvm_is_error_hva(vmaddr)) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); down_read(¤t->mm->mmap_sem); - rc = cond_set_guest_storage_key(current->mm, addr, key, &oldkey, + rc = cond_set_guest_storage_key(current->mm, vmaddr, key, &oldkey, m3 & SSKE_NQ, m3 & SSKE_MR, m3 & SSKE_MC); - up_read(¤t->mm->mmap_sem); - if (rc < 0) + + if (rc < 0) { + rc = fixup_user_fault(current, current->mm, vmaddr, + FAULT_FLAG_WRITE, &unlocked); + rc = !rc ? -EAGAIN : rc; + } + if (rc == -EFAULT) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - start += PAGE_SIZE; + + up_read(¤t->mm->mmap_sem); + if (rc >= 0) + start += PAGE_SIZE; } if (m3 & (SSKE_MC | SSKE_MR)) { @@ -946,11 +976,12 @@ static int handle_pfmf(struct kvm_vcpu *vcpu) } while (start != end) { - unsigned long useraddr; + unsigned long vmaddr; + bool unlocked = false; /* Translate guest address to host address */ - useraddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(start)); - if (kvm_is_error_hva(useraddr)) + vmaddr = gfn_to_hva(vcpu->kvm, gpa_to_gfn(start)); + if (kvm_is_error_hva(vmaddr)) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); if (vcpu->run->s.regs.gprs[reg1] & PFMF_CF) { @@ -964,14 +995,20 @@ static int handle_pfmf(struct kvm_vcpu *vcpu) if (rc) return rc; down_read(¤t->mm->mmap_sem); - rc = cond_set_guest_storage_key(current->mm, useraddr, + rc = cond_set_guest_storage_key(current->mm, vmaddr, key, NULL, nq, mr, mc); - up_read(¤t->mm->mmap_sem); - if (rc < 0) + if (rc < 0) { + rc = fixup_user_fault(current, current->mm, vmaddr, + FAULT_FLAG_WRITE, &unlocked); + rc = !rc ? -EAGAIN : rc; + } + if (rc == -EFAULT) return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - } - start += PAGE_SIZE; + up_read(¤t->mm->mmap_sem); + if (rc >= 0) + start += PAGE_SIZE; + } } if (vcpu->run->s.regs.gprs[reg1] & PFMF_FSC) { if (psw_bits(vcpu->arch.sie_block->gpsw).eaba == PSW_BITS_AMODE_64BIT) { |