diff options
-rw-r--r-- | arch/loongarch/include/asm/kvm_host.h | 3 | ||||
-rw-r--r-- | arch/loongarch/kvm/mmu.c | 124 |
2 files changed, 86 insertions, 41 deletions
diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h index 11328700d4fa..0e89db020481 100644 --- a/arch/loongarch/include/asm/kvm_host.h +++ b/arch/loongarch/include/asm/kvm_host.h @@ -45,7 +45,10 @@ struct kvm_vcpu_stat { u64 signal_exits; }; +#define KVM_MEM_HUGEPAGE_CAPABLE (1UL << 0) +#define KVM_MEM_HUGEPAGE_INCAPABLE (1UL << 1) struct kvm_arch_memory_slot { + unsigned long flags; }; struct kvm_context { diff --git a/arch/loongarch/kvm/mmu.c b/arch/loongarch/kvm/mmu.c index 80480df5f550..915f17527893 100644 --- a/arch/loongarch/kvm/mmu.c +++ b/arch/loongarch/kvm/mmu.c @@ -13,6 +13,16 @@ #include <asm/tlb.h> #include <asm/kvm_mmu.h> +static inline bool kvm_hugepage_capable(struct kvm_memory_slot *slot) +{ + return slot->arch.flags & KVM_MEM_HUGEPAGE_CAPABLE; +} + +static inline bool kvm_hugepage_incapable(struct kvm_memory_slot *slot) +{ + return slot->arch.flags & KVM_MEM_HUGEPAGE_INCAPABLE; +} + static inline void kvm_ptw_prepare(struct kvm *kvm, kvm_ptw_ctx *ctx) { ctx->level = kvm->arch.root_level; @@ -365,6 +375,69 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, kvm_ptw_top(kvm->arch.pgd, start << PAGE_SHIFT, end << PAGE_SHIFT, &ctx); } +int kvm_arch_prepare_memory_region(struct kvm *kvm, const struct kvm_memory_slot *old, + struct kvm_memory_slot *new, enum kvm_mr_change change) +{ + gpa_t gpa_start; + hva_t hva_start; + size_t size, gpa_offset, hva_offset; + + if ((change != KVM_MR_MOVE) && (change != KVM_MR_CREATE)) + return 0; + /* + * Prevent userspace from creating a memory region outside of the + * VM GPA address space + */ + if ((new->base_gfn + new->npages) > (kvm->arch.gpa_size >> PAGE_SHIFT)) + return -ENOMEM; + + new->arch.flags = 0; + size = new->npages * PAGE_SIZE; + gpa_start = new->base_gfn << PAGE_SHIFT; + hva_start = new->userspace_addr; + if (IS_ALIGNED(size, PMD_SIZE) && IS_ALIGNED(gpa_start, PMD_SIZE) + && IS_ALIGNED(hva_start, PMD_SIZE)) + new->arch.flags |= KVM_MEM_HUGEPAGE_CAPABLE; + else { + /* + * Pages belonging to memslots that don't have the same + * alignment within a PMD for userspace and GPA cannot be + * mapped with PMD entries, because we'll end up mapping + * the wrong pages. + * + * Consider a layout like the following: + * + * memslot->userspace_addr: + * +-----+--------------------+--------------------+---+ + * |abcde|fgh Stage-1 block | Stage-1 block tv|xyz| + * +-----+--------------------+--------------------+---+ + * + * memslot->base_gfn << PAGE_SIZE: + * +---+--------------------+--------------------+-----+ + * |abc|def Stage-2 block | Stage-2 block |tvxyz| + * +---+--------------------+--------------------+-----+ + * + * If we create those stage-2 blocks, we'll end up with this + * incorrect mapping: + * d -> f + * e -> g + * f -> h + */ + gpa_offset = gpa_start & (PMD_SIZE - 1); + hva_offset = hva_start & (PMD_SIZE - 1); + if (gpa_offset != hva_offset) { + new->arch.flags |= KVM_MEM_HUGEPAGE_INCAPABLE; + } else { + if (gpa_offset == 0) + gpa_offset = PMD_SIZE; + if ((size + gpa_offset) < (PMD_SIZE * 2)) + new->arch.flags |= KVM_MEM_HUGEPAGE_INCAPABLE; + } + } + + return 0; +} + void kvm_arch_commit_memory_region(struct kvm *kvm, struct kvm_memory_slot *old, const struct kvm_memory_slot *new, @@ -562,47 +635,23 @@ out: } static bool fault_supports_huge_mapping(struct kvm_memory_slot *memslot, - unsigned long hva, unsigned long map_size, bool write) + unsigned long hva, bool write) { - size_t size; - gpa_t gpa_start; - hva_t uaddr_start, uaddr_end; + hva_t start, end; /* Disable dirty logging on HugePages */ if (kvm_slot_dirty_track_enabled(memslot) && write) return false; - size = memslot->npages * PAGE_SIZE; - gpa_start = memslot->base_gfn << PAGE_SHIFT; - uaddr_start = memslot->userspace_addr; - uaddr_end = uaddr_start + size; + if (kvm_hugepage_capable(memslot)) + return true; - /* - * Pages belonging to memslots that don't have the same alignment - * within a PMD for userspace and GPA cannot be mapped with stage-2 - * PMD entries, because we'll end up mapping the wrong pages. - * - * Consider a layout like the following: - * - * memslot->userspace_addr: - * +-----+--------------------+--------------------+---+ - * |abcde|fgh Stage-1 block | Stage-1 block tv|xyz| - * +-----+--------------------+--------------------+---+ - * - * memslot->base_gfn << PAGE_SIZE: - * +---+--------------------+--------------------+-----+ - * |abc|def Stage-2 block | Stage-2 block |tvxyz| - * +---+--------------------+--------------------+-----+ - * - * If we create those stage-2 blocks, we'll end up with this incorrect - * mapping: - * d -> f - * e -> g - * f -> h - */ - if ((gpa_start & (map_size - 1)) != (uaddr_start & (map_size - 1))) + if (kvm_hugepage_incapable(memslot)) return false; + start = memslot->userspace_addr; + end = start + memslot->npages * PAGE_SIZE; + /* * Next, let's make sure we're not trying to map anything not covered * by the memslot. This means we have to prohibit block size mappings @@ -615,8 +664,7 @@ static bool fault_supports_huge_mapping(struct kvm_memory_slot *memslot, * userspace_addr or the base_gfn, as both are equally aligned (per * the check above) and equally sized. */ - return (hva & ~(map_size - 1)) >= uaddr_start && - (hva & ~(map_size - 1)) + map_size <= uaddr_end; + return (hva >= ALIGN(start, PMD_SIZE)) && (hva < ALIGN_DOWN(end, PMD_SIZE)); } /* @@ -842,7 +890,7 @@ retry: /* Disable dirty logging on HugePages */ level = 0; - if (!fault_supports_huge_mapping(memslot, hva, PMD_SIZE, write)) { + if (!fault_supports_huge_mapping(memslot, hva, write)) { level = 0; } else { level = host_pfn_mapping_level(kvm, gfn, memslot); @@ -901,12 +949,6 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) { } -int kvm_arch_prepare_memory_region(struct kvm *kvm, const struct kvm_memory_slot *old, - struct kvm_memory_slot *new, enum kvm_mr_change change) -{ - return 0; -} - void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, const struct kvm_memory_slot *memslot) { |