diff options
| -rw-r--r-- | arch/arm/include/asm/kvm_asm.h | 2 | ||||
| -rw-r--r-- | arch/arm/include/asm/kvm_host.h | 18 | ||||
| -rw-r--r-- | arch/arm/include/asm/kvm_mmu.h | 9 | ||||
| -rw-r--r-- | arch/arm/kvm/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm/kvm/arm.c | 37 | ||||
| -rw-r--r-- | arch/arm/kvm/interrupts.S | 7 | ||||
| -rw-r--r-- | arch/arm/kvm/mmu.c | 370 | ||||
| -rw-r--r-- | arch/arm/kvm/trace.h | 46 |
8 files changed, 488 insertions, 2 deletions
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h index 81324e2eb3f9..f6652f6c5d84 100644 --- a/arch/arm/include/asm/kvm_asm.h +++ b/arch/arm/include/asm/kvm_asm.h @@ -57,6 +57,7 @@ #define ARM_EXCEPTION_HVC 7 #ifndef __ASSEMBLY__ +struct kvm; struct kvm_vcpu; extern char __kvm_hyp_init[]; @@ -71,6 +72,7 @@ extern char __kvm_hyp_code_start[]; extern char __kvm_hyp_code_end[]; extern void __kvm_flush_vm_context(void); +extern void __kvm_tlb_flush_vmid(struct kvm *kvm); extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); #endif diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 067ef2898c26..3636c7ea4eb2 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -112,4 +112,22 @@ struct kvm_one_reg; int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); u64 kvm_call_hyp(void *hypfn, ...); + +#define KVM_ARCH_WANT_MMU_NOTIFIER +struct kvm; +int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); +int kvm_unmap_hva_range(struct kvm *kvm, + unsigned long start, unsigned long end); +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); + +/* We do not have shadow page tables, hence the empty hooks */ +static inline int kvm_age_hva(struct kvm *kvm, unsigned long hva) +{ + return 0; +} + +static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) +{ + return 0; +} #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index e8679b317b0f..499e7b0925ff 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -23,6 +23,15 @@ int create_hyp_mappings(void *from, void *to); int create_hyp_io_mappings(void *from, void *to, phys_addr_t); void free_hyp_pmds(void); +int kvm_alloc_stage2_pgd(struct kvm *kvm); +void kvm_free_stage2_pgd(struct kvm *kvm); +int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, + phys_addr_t pa, unsigned long size); + +int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run); + +void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu); + phys_addr_t kvm_mmu_get_httbr(void); int kvm_mmu_init(void); void kvm_clear_hyp_idmap(void); diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig index 4a01b6fbf380..05227cb57a7b 100644 --- a/arch/arm/kvm/Kconfig +++ b/arch/arm/kvm/Kconfig @@ -36,6 +36,7 @@ config KVM_ARM_HOST bool "KVM host support for ARM cpus." depends on KVM depends on MMU + select MMU_NOTIFIER ---help--- Provides host support for ARM processors. diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 2c6b780e78a7..d810afb6cb84 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -81,12 +81,33 @@ void kvm_arch_sync_events(struct kvm *kvm) { } +/** + * kvm_arch_init_vm - initializes a VM data structure + * @kvm: pointer to the KVM struct + */ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { + int ret = 0; + if (type) return -EINVAL; - return 0; + ret = kvm_alloc_stage2_pgd(kvm); + if (ret) + goto out_fail_alloc; + + ret = create_hyp_mappings(kvm, kvm + 1); + if (ret) + goto out_free_stage2_pgd; + + /* Mark the initial VMID generation invalid */ + kvm->arch.vmid_gen = 0; + + return ret; +out_free_stage2_pgd: + kvm_free_stage2_pgd(kvm); +out_fail_alloc: + return ret; } int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) @@ -104,10 +125,16 @@ int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages) return 0; } +/** + * kvm_arch_destroy_vm - destroy the VM data structure + * @kvm: pointer to the KVM struct + */ void kvm_arch_destroy_vm(struct kvm *kvm) { int i; + kvm_free_stage2_pgd(kvm); + for (i = 0; i < KVM_MAX_VCPUS; ++i) { if (kvm->vcpus[i]) { kvm_arch_vcpu_free(kvm->vcpus[i]); @@ -196,7 +223,13 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) if (err) goto free_vcpu; + err = create_hyp_mappings(vcpu, vcpu + 1); + if (err) + goto vcpu_uninit; + return vcpu; +vcpu_uninit: + kvm_vcpu_uninit(vcpu); free_vcpu: kmem_cache_free(kvm_vcpu_cache, vcpu); out: @@ -210,6 +243,8 @@ int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) { + kvm_mmu_free_memory_caches(vcpu); + kmem_cache_free(kvm_vcpu_cache, vcpu); } void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S index d10a8075409a..f701aff31e44 100644 --- a/arch/arm/kvm/interrupts.S +++ b/arch/arm/kvm/interrupts.S @@ -32,6 +32,13 @@ __kvm_hyp_code_start: /******************************************************************** * Flush per-VMID TLBs */ +ENTRY(__kvm_tlb_flush_vmid) + bx lr +ENDPROC(__kvm_tlb_flush_vmid) + +/******************************************************************** + * Flush TLBs and instruction caches of current CPU for all VMIDs + */ ENTRY(__kvm_flush_vm_context) bx lr ENDPROC(__kvm_flush_vm_context) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 4decdb618019..4347d68f052f 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -23,12 +23,21 @@ #include <asm/pgalloc.h> #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> +#include <asm/kvm_asm.h> #include <asm/mach/map.h> +#include <trace/events/kvm.h> + +#include "trace.h" extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[]; static DEFINE_MUTEX(kvm_hyp_pgd_mutex); +static void kvm_tlb_flush_vmid(struct kvm *kvm) +{ + kvm_call_hyp(__kvm_tlb_flush_vmid, kvm); +} + static void kvm_set_pte(pte_t *pte, pte_t new_pte) { pte_val(*pte) = new_pte; @@ -39,6 +48,38 @@ static void kvm_set_pte(pte_t *pte, pte_t new_pte) flush_pmd_entry(pte); } +static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, + int min, int max) +{ + void *page; + + BUG_ON(max > KVM_NR_MEM_OBJS); + if (cache->nobjs >= min) + return 0; + while (cache->nobjs < max) { + page = (void *)__get_free_page(PGALLOC_GFP); + if (!page) + return -ENOMEM; + cache->objects[cache->nobjs++] = page; + } + return 0; +} + +static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc) +{ + while (mc->nobjs) + free_page((unsigned long)mc->objects[--mc->nobjs]); +} + +static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc) +{ + void *p; + + BUG_ON(!mc || !mc->nobjs); + p = mc->objects[--mc->nobjs]; + return p; +} + static void free_ptes(pmd_t *pmd, unsigned long addr) { pte_t *pte; @@ -217,11 +258,333 @@ int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr) return __create_hyp_mappings(from, to, &pfn); } +/** + * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation. + * @kvm: The KVM struct pointer for the VM. + * + * Allocates the 1st level table only of size defined by S2_PGD_ORDER (can + * support either full 40-bit input addresses or limited to 32-bit input + * addresses). Clears the allocated pages. + * + * Note we don't need locking here as this is only called when the VM is + * created, which can only be done once. + */ +int kvm_alloc_stage2_pgd(struct kvm *kvm) +{ + pgd_t *pgd; + + if (kvm->arch.pgd != NULL) { + kvm_err("kvm_arch already initialized?\n"); + return -EINVAL; + } + + pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, S2_PGD_ORDER); + if (!pgd) + return -ENOMEM; + + /* stage-2 pgd must be aligned to its size */ + VM_BUG_ON((unsigned long)pgd & (S2_PGD_SIZE - 1)); + + memset(pgd, 0, PTRS_PER_S2_PGD * sizeof(pgd_t)); + clean_dcache_area(pgd, PTRS_PER_S2_PGD * sizeof(pgd_t)); + kvm->arch.pgd = pgd; + + return 0; +} + +static void clear_pud_entry(pud_t *pud) +{ + pmd_t *pmd_table = pmd_offset(pud, 0); + pud_clear(pud); + pmd_free(NULL, pmd_table); + put_page(virt_to_page(pud)); +} + +static void clear_pmd_entry(pmd_t *pmd) +{ + pte_t *pte_table = pte_offset_kernel(pmd, 0); + pmd_clear(pmd); + pte_free_kernel(NULL, pte_table); + put_page(virt_to_page(pmd)); +} + +static bool pmd_empty(pmd_t *pmd) +{ + struct page *pmd_page = virt_to_page(pmd); + return page_count(pmd_page) == 1; +} + +static void clear_pte_entry(pte_t *pte) +{ + if (pte_present(*pte)) { + kvm_set_pte(pte, __pte(0)); + put_page(virt_to_page(pte)); + } +} + +static bool pte_empty(pte_t *pte) +{ + struct page *pte_page = virt_to_page(pte); + return page_count(pte_page) == 1; +} + +/** + * unmap_stage2_range -- Clear stage2 page table entries to unmap a range + * @kvm: The VM pointer + * @start: The intermediate physical base address of the range to unmap + * @size: The size of the area to unmap + * + * Clear a range of stage-2 mappings, lowering the various ref-counts. Must + * be called while holding mmu_lock (unless for freeing the stage2 pgd before + * destroying the VM), otherwise another faulting VCPU may come in and mess + * with things behind our backs. + */ +static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + phys_addr_t addr = start, end = start + size; + u64 range; + + while (addr < end) { + pgd = kvm->arch.pgd + pgd_index(addr); + pud = pud_offset(pgd, addr); + if (pud_none(*pud)) { + addr += PUD_SIZE; + continue; + } + + pmd = pmd_offset(pud, addr); + if (pmd_none(*pmd)) { + addr += PMD_SIZE; + continue; + } + + pte = pte_offset_kernel(pmd, addr); + clear_pte_entry(pte); + range = PAGE_SIZE; + + /* If we emptied the pte, walk back up the ladder */ + if (pte_empty(pte)) { + clear_pmd_entry(pmd); + range = PMD_SIZE; + if (pmd_empty(pmd)) { + clear_pud_entry(pud); + range = PUD_SIZE; + } + } + + addr += range; + } +} + +/** + * kvm_free_stage2_pgd - free all stage-2 tables + * @kvm: The KVM struct pointer for the VM. + * + * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all + * underlying level-2 and level-3 tables before freeing the actual level-1 table + * and setting the struct pointer to NULL. + * + * Note we don't need locking here as this is only called when the VM is + * destroyed, which can only be done once. + */ +void kvm_free_stage2_pgd(struct kvm *kvm) +{ + if (kvm->arch.pgd == NULL) + return; + + unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE); + free_pages((unsigned long)kvm->arch.pgd, S2_PGD_ORDER); + kvm->arch.pgd = NULL; +} + + +static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, + phys_addr_t addr, const pte_t *new_pte, bool iomap) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte, old_pte; + + /* Create 2nd stage page table mapping - Level 1 */ + pgd = kvm->arch.pgd + pgd_index(addr); + pud = pud_offset(pgd, addr); + if (pud_none(*pud)) { + if (!cache) + return 0; /* ignore calls from kvm_set_spte_hva */ + pmd = mmu_memory_cache_alloc(cache); + pud_populate(NULL, pud, pmd); + pmd += pmd_index(addr); + get_page(virt_to_page(pud)); + } else + pmd = pmd_offset(pud, addr); + + /* Create 2nd stage page table mapping - Level 2 */ + if (pmd_none(*pmd)) { + if (!cache) + return 0; /* ignore calls from kvm_set_spte_hva */ + pte = mmu_memory_cache_alloc(cache); + clean_pte_table(pte); + pmd_populate_kernel(NULL, pmd, pte); + pte += pte_index(addr); + get_page(virt_to_page(pmd)); + } else + pte = pte_offset_kernel(pmd, addr); + + if (iomap && pte_present(*pte)) + return -EFAULT; + + /* Create 2nd stage page table mapping - Level 3 */ + old_pte = *pte; + kvm_set_pte(pte, *new_pte); + if (pte_present(old_pte)) + kvm_tlb_flush_vmid(kvm); + else + get_page(virt_to_page(pte)); + + return 0; +} + +/** + * kvm_phys_addr_ioremap - map a device range to guest IPA + * + * @kvm: The KVM pointer + * @guest_ipa: The IPA at which to insert the mapping + * @pa: The physical address of the device + * @size: The size of the mapping + */ +int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, + phys_addr_t pa, unsigned long size) +{ + phys_addr_t addr, end; + int ret = 0; + unsigned long pfn; + struct kvm_mmu_memory_cache cache = { 0, }; + + end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK; + pfn = __phys_to_pfn(pa); + + for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) { + pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE | L_PTE_S2_RDWR); + + ret = mmu_topup_memory_cache(&cache, 2, 2); + if (ret) + goto out; + spin_lock(&kvm->mmu_lock); + ret = stage2_set_pte(kvm, &cache, addr, &pte, true); + spin_unlock(&kvm->mmu_lock); + if (ret) + goto out; + + pfn++; + } + +out: + mmu_free_memory_cache(&cache); + return ret; +} + int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run) { return -EINVAL; } +static void handle_hva_to_gpa(struct kvm *kvm, + unsigned long start, + unsigned long end, + void (*handler)(struct kvm *kvm, + gpa_t gpa, void *data), + void *data) +{ + struct kvm_memslots *slots; + struct kvm_memory_slot *memslot; + + slots = kvm_memslots(kvm); + + /* we only care about the pages that the guest sees */ + kvm_for_each_memslot(memslot, slots) { + unsigned long hva_start, hva_end; + gfn_t gfn, gfn_end; + + hva_start = max(start, memslot->userspace_addr); + hva_end = min(end, memslot->userspace_addr + + (memslot->npages << PAGE_SHIFT)); + if (hva_start >= hva_end) + continue; + + /* + * {gfn(page) | page intersects with [hva_start, hva_end)} = + * {gfn_start, gfn_start+1, ..., gfn_end-1}. + */ + gfn = hva_to_gfn_memslot(hva_start, memslot); + gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot); + + for (; gfn < gfn_end; ++gfn) { + gpa_t gpa = gfn << PAGE_SHIFT; + handler(kvm, gpa, data); + } + } +} + +static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data) +{ + unmap_stage2_range(kvm, gpa, PAGE_SIZE); + kvm_tlb_flush_vmid(kvm); +} + +int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) +{ + unsigned long end = hva + PAGE_SIZE; + + if (!kvm->arch.pgd) + return 0; + + trace_kvm_unmap_hva(hva); + handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL); + return 0; +} + +int kvm_unmap_hva_range(struct kvm *kvm, + unsigned long start, unsigned long end) +{ + if (!kvm->arch.pgd) + return 0; + + trace_kvm_unmap_hva_range(start, end); + handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL); + return 0; +} + +static void kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void *data) +{ + pte_t *pte = (pte_t *)data; + + stage2_set_pte(kvm, NULL, gpa, pte, false); +} + + +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) +{ + unsigned long end = hva + PAGE_SIZE; + pte_t stage2_pte; + + if (!kvm->arch.pgd) + return; + + trace_kvm_set_spte_hva(hva); + stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2); + handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte); +} + +void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) +{ + mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); +} + phys_addr_t kvm_mmu_get_httbr(void) { VM_BUG_ON(!virt_addr_valid(hyp_pgd)); @@ -230,7 +593,12 @@ phys_addr_t kvm_mmu_get_httbr(void) int kvm_mmu_init(void) { - return hyp_pgd ? 0 : -ENOMEM; + if (!hyp_pgd) { + kvm_err("Hyp mode PGD not allocated\n"); + return -ENOMEM; + } + + return 0; } /** diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h index f8869c19c0a3..862b2cc12fbe 100644 --- a/arch/arm/kvm/trace.h +++ b/arch/arm/kvm/trace.h @@ -39,7 +39,53 @@ TRACE_EVENT(kvm_exit, TP_printk("PC: 0x%08lx", __entry->vcpu_pc) ); +TRACE_EVENT(kvm_unmap_hva, + TP_PROTO(unsigned long hva), + TP_ARGS(hva), + TP_STRUCT__entry( + __field( unsigned long, hva ) + ), + + TP_fast_assign( + __entry->hva = hva; + ), + + TP_printk("mmu notifier unmap hva: %#08lx", __entry->hva) +); + +TRACE_EVENT(kvm_unmap_hva_range, + TP_PROTO(unsigned long start, unsigned long end), + TP_ARGS(start, end), + + TP_STRUCT__entry( + __field( unsigned long, start ) + __field( unsigned long, end ) + ), + + TP_fast_assign( + __entry->start = start; + __entry->end = end; + ), + + TP_printk("mmu notifier unmap range: %#08lx -- %#08lx", + __entry->start, __entry->end) +); + +TRACE_EVENT(kvm_set_spte_hva, + TP_PROTO(unsigned long hva), + TP_ARGS(hva), + + TP_STRUCT__entry( + __field( unsigned long, hva ) + ), + + TP_fast_assign( + __entry->hva = hva; + ), + + TP_printk("mmu notifier set pte hva: %#08lx", __entry->hva) +); #endif /* _TRACE_KVM_H */ |