diff options
-rw-r--r-- | Documentation/virtual/kvm/api.txt | 16 | ||||
-rw-r--r-- | arch/s390/include/asm/gmap.h | 10 | ||||
-rw-r--r-- | arch/s390/include/asm/hugetlb.h | 5 | ||||
-rw-r--r-- | arch/s390/include/asm/mmu.h | 2 | ||||
-rw-r--r-- | arch/s390/include/asm/mmu_context.h | 1 | ||||
-rw-r--r-- | arch/s390/include/asm/pgtable.h | 13 | ||||
-rw-r--r-- | arch/s390/kvm/kvm-s390.c | 82 | ||||
-rw-r--r-- | arch/s390/kvm/priv.c | 103 | ||||
-rw-r--r-- | arch/s390/mm/gmap.c | 454 | ||||
-rw-r--r-- | arch/s390/mm/hugetlbpage.c | 24 | ||||
-rw-r--r-- | arch/s390/mm/pageattr.c | 6 | ||||
-rw-r--r-- | arch/s390/mm/pgtable.c | 159 | ||||
-rw-r--r-- | include/uapi/linux/kvm.h | 1 |
13 files changed, 756 insertions, 120 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index d10944e619d3..cb8db4f9d097 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -4391,6 +4391,22 @@ all such vmexits. Do not enable KVM_FEATURE_PV_UNHALT if you disable HLT exits. +7.14 KVM_CAP_S390_HPAGE_1M + +Architectures: s390 +Parameters: none +Returns: 0 on success, -EINVAL if hpage module parameter was not set + or cmma is enabled + +With this capability the KVM support for memory backing with 1m pages +through hugetlbfs can be enabled for a VM. After the capability is +enabled, cmma can't be enabled anymore and pfmfi and the storage key +interpretation are disabled. If cmma has already been enabled or the +hpage module parameter is not set to 1, -EINVAL is returned. + +While it is generally possible to create a huge page backed VM without +this capability, the VM will not be able to run. + 8. Other capabilities. ---------------------- diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h index e07cce88dfb0..fcbd638fb9f4 100644 --- a/arch/s390/include/asm/gmap.h +++ b/arch/s390/include/asm/gmap.h @@ -9,6 +9,14 @@ #ifndef _ASM_S390_GMAP_H #define _ASM_S390_GMAP_H +/* Generic bits for GMAP notification on DAT table entry changes. */ +#define GMAP_NOTIFY_SHADOW 0x2 +#define GMAP_NOTIFY_MPROT 0x1 + +/* Status bits only for huge segment entries */ +#define _SEGMENT_ENTRY_GMAP_IN 0x8000 /* invalidation notify bit */ +#define _SEGMENT_ENTRY_GMAP_UC 0x4000 /* dirty (migration) */ + /** * struct gmap_struct - guest address space * @list: list head for the mm->context gmap list @@ -132,4 +140,6 @@ void gmap_pte_notify(struct mm_struct *, unsigned long addr, pte_t *, int gmap_mprotect_notify(struct gmap *, unsigned long start, unsigned long len, int prot); +void gmap_sync_dirty_log_pmd(struct gmap *gmap, unsigned long dirty_bitmap[4], + unsigned long gaddr, unsigned long vmaddr); #endif /* _ASM_S390_GMAP_H */ diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h index 9c5fc50204dd..2d1afa58a4b6 100644 --- a/arch/s390/include/asm/hugetlb.h +++ b/arch/s390/include/asm/hugetlb.h @@ -37,7 +37,10 @@ static inline int prepare_hugepage_range(struct file *file, return 0; } -#define arch_clear_hugepage_flags(page) do { } while (0) +static inline void arch_clear_hugepage_flags(struct page *page) +{ + clear_bit(PG_arch_1, &page->flags); +} static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep, unsigned long sz) diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h index f5ff9dbad8ac..f31a15044c24 100644 --- a/arch/s390/include/asm/mmu.h +++ b/arch/s390/include/asm/mmu.h @@ -24,6 +24,8 @@ typedef struct { unsigned int uses_skeys:1; /* The mmu context uses CMM. */ unsigned int uses_cmm:1; + /* The gmaps associated with this context are allowed to use huge pages. */ + unsigned int allow_gmap_hpage_1m:1; } mm_context_t; #define INIT_MM_CONTEXT(name) \ diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h index d16bc79c30bb..0717ee76885d 100644 --- a/arch/s390/include/asm/mmu_context.h +++ b/arch/s390/include/asm/mmu_context.h @@ -32,6 +32,7 @@ static inline int init_new_context(struct task_struct *tsk, mm->context.has_pgste = 0; mm->context.uses_skeys = 0; mm->context.uses_cmm = 0; + mm->context.allow_gmap_hpage_1m = 0; #endif switch (mm->context.asce_limit) { case _REGION2_SIZE: diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 5ab636089c60..0e7cb0dc9c33 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -268,8 +268,10 @@ static inline int is_module_addr(void *addr) #define _REGION_ENTRY_BITS_LARGE 0xffffffff8000fe2fUL /* Bits in the segment table entry */ -#define _SEGMENT_ENTRY_BITS 0xfffffffffffffe33UL -#define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL +#define _SEGMENT_ENTRY_BITS 0xfffffffffffffe33UL +#define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL +#define _SEGMENT_ENTRY_HARDWARE_BITS 0xfffffffffffffe30UL +#define _SEGMENT_ENTRY_HARDWARE_BITS_LARGE 0xfffffffffff00730UL #define _SEGMENT_ENTRY_ORIGIN_LARGE ~0xfffffUL /* large page address */ #define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* page table origin */ #define _SEGMENT_ENTRY_PROTECT 0x200 /* segment protection bit */ @@ -1101,7 +1103,8 @@ int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *sptep, pte_t *tptep, pte_t pte); void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep); -bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long address); +bool ptep_test_and_clear_uc(struct mm_struct *mm, unsigned long address, + pte_t *ptep); int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, unsigned char key, bool nq); int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr, @@ -1116,6 +1119,10 @@ int set_pgste_bits(struct mm_struct *mm, unsigned long addr, int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep); int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc, unsigned long *oldpte, unsigned long *oldpgste); +void gmap_pmdp_csp(struct mm_struct *mm, unsigned long vmaddr); +void gmap_pmdp_invalidate(struct mm_struct *mm, unsigned long vmaddr); +void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr); +void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr); /* * Certain architectures need to do special things when PTEs 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) { diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index bc56ec8abcf7..bb44990c8212 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -2,8 +2,10 @@ /* * KVM guest address space mapping code * - * Copyright IBM Corp. 2007, 2016 + * Copyright IBM Corp. 2007, 2016, 2018 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> + * David Hildenbrand <david@redhat.com> + * Janosch Frank <frankja@linux.vnet.ibm.com> */ #include <linux/kernel.h> @@ -521,6 +523,9 @@ void gmap_unlink(struct mm_struct *mm, unsigned long *table, rcu_read_unlock(); } +static void gmap_pmdp_xchg(struct gmap *gmap, pmd_t *old, pmd_t new, + unsigned long gaddr); + /** * gmap_link - set up shadow page tables to connect a host to a guest address * @gmap: pointer to guest mapping meta data structure @@ -541,6 +546,7 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) p4d_t *p4d; pud_t *pud; pmd_t *pmd; + u64 unprot; int rc; BUG_ON(gmap_is_shadow(gmap)); @@ -584,8 +590,8 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) return -EFAULT; pmd = pmd_offset(pud, vmaddr); VM_BUG_ON(pmd_none(*pmd)); - /* large pmds cannot yet be handled */ - if (pmd_large(*pmd)) + /* Are we allowed to use huge pages? */ + if (pmd_large(*pmd) && !gmap->mm->context.allow_gmap_hpage_1m) return -EFAULT; /* Link gmap segment table entry location to page table. */ rc = radix_tree_preload(GFP_KERNEL); @@ -596,10 +602,22 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) if (*table == _SEGMENT_ENTRY_EMPTY) { rc = radix_tree_insert(&gmap->host_to_guest, vmaddr >> PMD_SHIFT, table); - if (!rc) - *table = pmd_val(*pmd); - } else - rc = 0; + if (!rc) { + if (pmd_large(*pmd)) { + *table = (pmd_val(*pmd) & + _SEGMENT_ENTRY_HARDWARE_BITS_LARGE) + | _SEGMENT_ENTRY_GMAP_UC; + } else + *table = pmd_val(*pmd) & + _SEGMENT_ENTRY_HARDWARE_BITS; + } + } else if (*table & _SEGMENT_ENTRY_PROTECT && + !(pmd_val(*pmd) & _SEGMENT_ENTRY_PROTECT)) { + unprot = (u64)*table; + unprot &= ~_SEGMENT_ENTRY_PROTECT; + unprot |= _SEGMENT_ENTRY_GMAP_UC; + gmap_pmdp_xchg(gmap, (pmd_t *)table, __pmd(unprot), gaddr); + } spin_unlock(&gmap->guest_table_lock); spin_unlock(ptl); radix_tree_preload_end(); @@ -690,6 +708,12 @@ void gmap_discard(struct gmap *gmap, unsigned long from, unsigned long to) vmaddr |= gaddr & ~PMD_MASK; /* Find vma in the parent mm */ vma = find_vma(gmap->mm, vmaddr); + /* + * We do not discard pages that are backed by + * hugetlbfs, so we don't have to refault them. + */ + if (vma && is_vm_hugetlb_page(vma)) + continue; size = min(to - gaddr, PMD_SIZE - (gaddr & ~PMD_MASK)); zap_page_range(vma, vmaddr, size); } @@ -864,7 +888,128 @@ static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr, */ static void gmap_pte_op_end(spinlock_t *ptl) { - spin_unlock(ptl); + if (ptl) + spin_unlock(ptl); +} + +/** + * gmap_pmd_op_walk - walk the gmap tables, get the guest table lock + * and return the pmd pointer + * @gmap: pointer to guest mapping meta data structure + * @gaddr: virtual address in the guest address space + * + * Returns a pointer to the pmd for a guest address, or NULL + */ +static inline pmd_t *gmap_pmd_op_walk(struct gmap *gmap, unsigned long gaddr) +{ + pmd_t *pmdp; + + BUG_ON(gmap_is_shadow(gmap)); + spin_lock(&gmap->guest_table_lock); + pmdp = (pmd_t *) gmap_table_walk(gmap, gaddr, 1); + + if (!pmdp || pmd_none(*pmdp)) { + spin_unlock(&gmap->guest_table_lock); + return NULL; + } + + /* 4k page table entries are locked via the pte (pte_alloc_map_lock). */ + if (!pmd_large(*pmdp)) + spin_unlock(&gmap->guest_table_lock); + return pmdp; +} + +/** + * gmap_pmd_op_end - release the guest_table_lock if needed + * @gmap: pointer to the guest mapping meta data structure + * @pmdp: pointer to the pmd + */ +static inline void gmap_pmd_op_end(struct gmap *gmap, pmd_t *pmdp) +{ + if (pmd_large(*pmdp)) + spin_unlock(&gmap->guest_table_lock); +} + +/* + * gmap_protect_pmd - remove access rights to memory and set pmd notification bits + * @pmdp: pointer to the pmd to be protected + * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE + * @bits: notification bits to set + * + * Returns: + * 0 if successfully protected + * -EAGAIN if a fixup is needed + * -EINVAL if unsupported notifier bits have been specified + * + * Expected to be called with sg->mm->mmap_sem in read and + * guest_table_lock held. + */ +static int gmap_protect_pmd(struct gmap *gmap, unsigned long gaddr, + pmd_t *pmdp, int prot, unsigned long bits) +{ + int pmd_i = pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID; + int pmd_p = pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT; + pmd_t new = *pmdp; + + /* Fixup needed */ + if ((pmd_i && (prot != PROT_NONE)) || (pmd_p && (prot == PROT_WRITE))) + return -EAGAIN; + + if (prot == PROT_NONE && !pmd_i) { + pmd_val(new) |= _SEGMENT_ENTRY_INVALID; + gmap_pmdp_xchg(gmap, pmdp, new, gaddr); + } + + if (prot == PROT_READ && !pmd_p) { + pmd_val(new) &= ~_SEGMENT_ENTRY_INVALID; + pmd_val(new) |= _SEGMENT_ENTRY_PROTECT; + gmap_pmdp_xchg(gmap, pmdp, new, gaddr); + } + + if (bits & GMAP_NOTIFY_MPROT) + pmd_val(*pmdp) |= _SEGMENT_ENTRY_GMAP_IN; + + /* Shadow GMAP protection needs split PMDs */ + if (bits & GMAP_NOTIFY_SHADOW) + return -EINVAL; + + return 0; +} + +/* + * gmap_protect_pte - remove access rights to memory and set pgste bits + * @gmap: pointer to guest mapping meta data structure + * @gaddr: virtual address in the guest address space + * @pmdp: pointer to the pmd associated with the pte + * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE + * @bits: notification bits to set + * + * Returns 0 if successfully protected, -ENOMEM if out of memory and + * -EAGAIN if a fixup is needed. + * + * Expected to be called with sg->mm->mmap_sem in read + */ +static int gmap_protect_pte(struct gmap *gmap, unsigned long gaddr, + pmd_t *pmdp, int prot, unsigned long bits) +{ + int rc; + pte_t *ptep; + spinlock_t *ptl = NULL; + unsigned long pbits = 0; + + if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID) + return -EAGAIN; + + ptep = pte_alloc_map_lock(gmap->mm, pmdp, gaddr, &ptl); + if (!ptep) + return -ENOMEM; + + pbits |= (bits & GMAP_NOTIFY_MPROT) ? PGSTE_IN_BIT : 0; + pbits |= (bits & GMAP_NOTIFY_SHADOW) ? PGSTE_VSIE_BIT : 0; + /* Protect and unlock. */ + rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, pbits); + gmap_pte_op_end(ptl); + return rc; } /* @@ -883,30 +1028,45 @@ static void gmap_pte_op_end(spinlock_t *ptl) static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr, unsigned long len, int prot, unsigned long bits) { - unsigned long vmaddr; - spinlock_t *ptl; - pte_t *ptep; + unsigned long vmaddr, dist; + pmd_t *pmdp; int rc; BUG_ON(gmap_is_shadow(gmap)); while (len) { rc = -EAGAIN; - ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); - if (ptep) { - rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits); - gmap_pte_op_end(ptl); + pmdp = gmap_pmd_op_walk(gmap, gaddr); + if (pmdp) { + if (!pmd_large(*pmdp)) { + rc = gmap_protect_pte(gmap, gaddr, pmdp, prot, + bits); + if (!rc) { + len -= PAGE_SIZE; + gaddr += PAGE_SIZE; + } + } else { + rc = gmap_protect_pmd(gmap, gaddr, pmdp, prot, + bits); + if (!rc) { + dist = HPAGE_SIZE - (gaddr & ~HPAGE_MASK); + len = len < dist ? 0 : len - dist; + gaddr = (gaddr & HPAGE_MASK) + HPAGE_SIZE; + } + } + gmap_pmd_op_end(gmap, pmdp); } if (rc) { + if (rc == -EINVAL) + return rc; + + /* -EAGAIN, fixup of userspace mm and gmap */ vmaddr = __gmap_translate(gmap, gaddr); if (IS_ERR_VALUE(vmaddr)) return vmaddr; rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, prot); if (rc) return rc; - continue; } - gaddr += PAGE_SIZE; - len -= PAGE_SIZE; } return 0; } @@ -935,7 +1095,7 @@ int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr, if (!MACHINE_HAS_ESOP && prot == PROT_READ) return -EINVAL; down_read(&gmap->mm->mmap_sem); - rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT); + rc = gmap_protect_range(gmap, gaddr, len, prot, GMAP_NOTIFY_MPROT); up_read(&gmap->mm->mmap_sem); return rc; } @@ -1474,6 +1634,7 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, unsigned long limit; int rc; + BUG_ON(parent->mm->context.allow_gmap_hpage_1m); BUG_ON(gmap_is_shadow(parent)); spin_lock(&parent->shadow_lock); sg = gmap_find_shadow(parent, asce, edat_level); @@ -1526,7 +1687,7 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, down_read(&parent->mm->mmap_sem); rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN, ((asce & _ASCE_TABLE_LENGTH) + 1) * PAGE_SIZE, - PROT_READ, PGSTE_VSIE_BIT); + PROT_READ, GMAP_NOTIFY_SHADOW); up_read(&parent->mm->mmap_sem); spin_lock(&parent->shadow_lock); new->initialized = true; @@ -2092,6 +2253,225 @@ void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, } EXPORT_SYMBOL_GPL(ptep_notify); +static void pmdp_notify_gmap(struct gmap *gmap, pmd_t *pmdp, + unsigned long gaddr) +{ + pmd_val(*pmdp) &= ~_SEGMENT_ENTRY_GMAP_IN; + gmap_call_notifier(gmap, gaddr, gaddr + HPAGE_SIZE - 1); +} + +/** + * gmap_pmdp_xchg - exchange a gmap pmd with another + * @gmap: pointer to the guest address space structure + * @pmdp: pointer to the pmd entry + * @new: replacement entry + * @gaddr: the affected guest address + * + * This function is assumed to be called with the guest_table_lock + * held. + */ +static void gmap_pmdp_xchg(struct gmap *gmap, pmd_t *pmdp, pmd_t new, + unsigned long gaddr) +{ + gaddr &= HPAGE_MASK; + pmdp_notify_gmap(gmap, pmdp, gaddr); + pmd_val(new) &= ~_SEGMENT_ENTRY_GMAP_IN; + if (MACHINE_HAS_TLB_GUEST) + __pmdp_idte(gaddr, (pmd_t *)pmdp, IDTE_GUEST_ASCE, gmap->asce, + IDTE_GLOBAL); + else if (MACHINE_HAS_IDTE) + __pmdp_idte(gaddr, (pmd_t *)pmdp, 0, 0, IDTE_GLOBAL); + else + __pmdp_csp(pmdp); + *pmdp = new; +} + +static void gmap_pmdp_clear(struct mm_struct *mm, unsigned long vmaddr, + int purge) +{ + pmd_t *pmdp; + struct gmap *gmap; + unsigned long gaddr; + + rcu_read_lock(); + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { + spin_lock(&gmap->guest_table_lock); + pmdp = (pmd_t *)radix_tree_delete(&gmap->host_to_guest, + vmaddr >> PMD_SHIFT); + if (pmdp) { + gaddr = __gmap_segment_gaddr((unsigned long *)pmdp); + pmdp_notify_gmap(gmap, pmdp, gaddr); + WARN_ON(pmd_val(*pmdp) & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE | + _SEGMENT_ENTRY_GMAP_UC)); + if (purge) + __pmdp_csp(pmdp); + pmd_val(*pmdp) = _SEGMENT_ENTRY_EMPTY; + } + spin_unlock(&gmap->guest_table_lock); + } + rcu_read_unlock(); +} + +/** + * gmap_pmdp_invalidate - invalidate all affected guest pmd entries without + * flushing + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_invalidate(struct mm_struct *mm, unsigned long vmaddr) +{ + gmap_pmdp_clear(mm, vmaddr, 0); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_invalidate); + +/** + * gmap_pmdp_csp - csp all affected guest pmd entries + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_csp(struct mm_struct *mm, unsigned long vmaddr) +{ + gmap_pmdp_clear(mm, vmaddr, 1); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_csp); + +/** + * gmap_pmdp_idte_local - invalidate and clear a guest pmd entry + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr) +{ + unsigned long *entry, gaddr; + struct gmap *gmap; + pmd_t *pmdp; + + rcu_read_lock(); + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { + spin_lock(&gmap->guest_table_lock); + entry = radix_tree_delete(&gmap->host_to_guest, + vmaddr >> PMD_SHIFT); + if (entry) { + pmdp = (pmd_t *)entry; + gaddr = __gmap_segment_gaddr(entry); + pmdp_notify_gmap(gmap, pmdp, gaddr); + WARN_ON(*entry & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE | + _SEGMENT_ENTRY_GMAP_UC)); + if (MACHINE_HAS_TLB_GUEST) + __pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE, + gmap->asce, IDTE_LOCAL); + else if (MACHINE_HAS_IDTE) + __pmdp_idte(gaddr, pmdp, 0, 0, IDTE_LOCAL); + *entry = _SEGMENT_ENTRY_EMPTY; + } + spin_unlock(&gmap->guest_table_lock); + } + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_idte_local); + +/** + * gmap_pmdp_idte_global - invalidate and clear a guest pmd entry + * @mm: pointer to the process mm_struct + * @vmaddr: virtual address in the process address space + */ +void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr) +{ + unsigned long *entry, gaddr; + struct gmap *gmap; + pmd_t *pmdp; + + rcu_read_lock(); + list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { + spin_lock(&gmap->guest_table_lock); + entry = radix_tree_delete(&gmap->host_to_guest, + vmaddr >> PMD_SHIFT); + if (entry) { + pmdp = (pmd_t *)entry; + gaddr = __gmap_segment_gaddr(entry); + pmdp_notify_gmap(gmap, pmdp, gaddr); + WARN_ON(*entry & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE | + _SEGMENT_ENTRY_GMAP_UC)); + if (MACHINE_HAS_TLB_GUEST) + __pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE, + gmap->asce, IDTE_GLOBAL); + else if (MACHINE_HAS_IDTE) + __pmdp_idte(gaddr, pmdp, 0, 0, IDTE_GLOBAL); + else + __pmdp_csp(pmdp); + *entry = _SEGMENT_ENTRY_EMPTY; + } + spin_unlock(&gmap->guest_table_lock); + } + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(gmap_pmdp_idte_global); + +/** + * gmap_test_and_clear_dirty_pmd - test and reset segment dirty status + * @gmap: pointer to guest address space + * @pmdp: pointer to the pmd to be tested + * @gaddr: virtual address in the guest address space + * + * This function is assumed to be called with the guest_table_lock + * held. + */ +bool gmap_test_and_clear_dirty_pmd(struct gmap *gmap, pmd_t *pmdp, + unsigned long gaddr) +{ + if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID) + return false; + + /* Already protected memory, which did not change is clean */ + if (pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT && + !(pmd_val(*pmdp) & _SEGMENT_ENTRY_GMAP_UC)) + return false; + + /* Clear UC indication and reset protection */ + pmd_val(*pmdp) &= ~_SEGMENT_ENTRY_GMAP_UC; + gmap_protect_pmd(gmap, gaddr, pmdp, PROT_READ, 0); + return true; +} + +/** + * gmap_sync_dirty_log_pmd - set bitmap based on dirty status of segment + * @gmap: pointer to guest address space + * @bitmap: dirty bitmap for this pmd + * @gaddr: virtual address in the guest address space + * @vmaddr: virtual address in the host address space + * + * This function is assumed to be called with the guest_table_lock + * held. + */ +void gmap_sync_dirty_log_pmd(struct gmap *gmap, unsigned long bitmap[4], + unsigned long gaddr, unsigned long vmaddr) +{ + int i; + pmd_t *pmdp; + pte_t *ptep; + spinlock_t *ptl; + + pmdp = gmap_pmd_op_walk(gmap, gaddr); + if (!pmdp) + return; + + if (pmd_large(*pmdp)) { + if (gmap_test_and_clear_dirty_pmd(gmap, pmdp, gaddr)) + bitmap_fill(bitmap, _PAGE_ENTRIES); + } else { + for (i = 0; i < _PAGE_ENTRIES; i++, vmaddr += PAGE_SIZE) { + ptep = pte_alloc_map_lock(gmap->mm, pmdp, vmaddr, &ptl); + if (!ptep) + continue; + if (ptep_test_and_clear_uc(gmap->mm, vmaddr, ptep)) + set_bit(i, bitmap); |