diff options
| -rw-r--r-- | drivers/kvm/kvm.h | 7 | ||||
| -rw-r--r-- | drivers/kvm/kvm_main.c | 47 | ||||
| -rw-r--r-- | drivers/kvm/mmu.c | 40 | ||||
| -rw-r--r-- | include/linux/kvm.h | 3 |
4 files changed, 94 insertions, 3 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index 1965438..9f10c37 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -40,6 +40,8 @@ #define KVM_MAX_VCPUS 4 #define KVM_ALIAS_SLOTS 4 #define KVM_MEMORY_SLOTS 8 +#define KVM_PERMILLE_MMU_PAGES 20 +#define KVM_MIN_ALLOC_MMU_PAGES 64 #define KVM_NUM_MMU_PAGES 1024 #define KVM_MIN_FREE_MMU_PAGES 5 #define KVM_REFILL_PAGES 25 @@ -418,7 +420,9 @@ struct kvm { * Hash table of struct kvm_mmu_page. */ struct list_head active_mmu_pages; - int n_free_mmu_pages; + unsigned int n_free_mmu_pages; + unsigned int n_requested_mmu_pages; + unsigned int n_alloc_mmu_pages; struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES]; struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; unsigned long rmap_overflow; @@ -547,6 +551,7 @@ void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte); int kvm_mmu_reset_context(struct kvm_vcpu *vcpu); void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); void kvm_mmu_zap_all(struct kvm *kvm); +void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages); hpa_t gpa_to_hpa(struct kvm_vcpu *vcpu, gpa_t gpa); #define HPA_MSB ((sizeof(hpa_t) * 8) - 1) diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index cac328b..2bb1f2f 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -743,6 +743,24 @@ static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm, if (mem->slot >= kvm->nmemslots) kvm->nmemslots = mem->slot + 1; + if (!kvm->n_requested_mmu_pages) { + unsigned int n_pages; + + if (npages) { + n_pages = npages * KVM_PERMILLE_MMU_PAGES / 1000; + kvm_mmu_change_mmu_pages(kvm, kvm->n_alloc_mmu_pages + + n_pages); + } else { + unsigned int nr_mmu_pages; + + n_pages = old.npages * KVM_PERMILLE_MMU_PAGES / 1000; + nr_mmu_pages = kvm->n_alloc_mmu_pages - n_pages; + nr_mmu_pages = max(nr_mmu_pages, + (unsigned int) KVM_MIN_ALLOC_MMU_PAGES); + kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages); + } + } + *memslot = new; kvm_mmu_slot_remove_write_access(kvm, mem->slot); @@ -760,6 +778,26 @@ out: return r; } +static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm, + u32 kvm_nr_mmu_pages) +{ + if (kvm_nr_mmu_pages < KVM_MIN_ALLOC_MMU_PAGES) + return -EINVAL; + + mutex_lock(&kvm->lock); + + kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages); + kvm->n_requested_mmu_pages = kvm_nr_mmu_pages; + + mutex_unlock(&kvm->lock); + return 0; +} + +static int kvm_vm_ioctl_get_nr_mmu_pages(struct kvm *kvm) +{ + return kvm->n_alloc_mmu_pages; +} + /* * Get (and clear) the dirty memory log for a memory slot. */ @@ -3071,6 +3109,14 @@ static long kvm_vm_ioctl(struct file *filp, goto out; break; } + case KVM_SET_NR_MMU_PAGES: + r = kvm_vm_ioctl_set_nr_mmu_pages(kvm, arg); + if (r) + goto out; + break; + case KVM_GET_NR_MMU_PAGES: + r = kvm_vm_ioctl_get_nr_mmu_pages(kvm); + break; case KVM_GET_DIRTY_LOG: { struct kvm_dirty_log log; @@ -3278,6 +3324,7 @@ static long kvm_dev_ioctl(struct file *filp, switch (ext) { case KVM_CAP_IRQCHIP: case KVM_CAP_HLT: + case KVM_CAP_MMU_SHADOW_CACHE_CONTROL: r = 1; break; default: diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index 72757db..6cda1fe 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -747,6 +747,40 @@ static void kvm_mmu_zap_page(struct kvm *kvm, kvm_mmu_reset_last_pte_updated(kvm); } +/* + * Changing the number of mmu pages allocated to the vm + * Note: if kvm_nr_mmu_pages is too small, you will get dead lock + */ +void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages) +{ + /* + * If we set the number of mmu pages to be smaller be than the + * number of actived pages , we must to free some mmu pages before we + * change the value + */ + + if ((kvm->n_alloc_mmu_pages - kvm->n_free_mmu_pages) > + kvm_nr_mmu_pages) { + int n_used_mmu_pages = kvm->n_alloc_mmu_pages + - kvm->n_free_mmu_pages; + + while (n_used_mmu_pages > kvm_nr_mmu_pages) { + struct kvm_mmu_page *page; + + page = container_of(kvm->active_mmu_pages.prev, + struct kvm_mmu_page, link); + kvm_mmu_zap_page(kvm, page); + n_used_mmu_pages--; + } + kvm->n_free_mmu_pages = 0; + } + else + kvm->n_free_mmu_pages += kvm_nr_mmu_pages + - kvm->n_alloc_mmu_pages; + + kvm->n_alloc_mmu_pages = kvm_nr_mmu_pages; +} + static int kvm_mmu_unprotect_page(struct kvm_vcpu *vcpu, gfn_t gfn) { unsigned index; @@ -1297,8 +1331,10 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) ASSERT(vcpu); - vcpu->kvm->n_free_mmu_pages = KVM_NUM_MMU_PAGES; - + if (vcpu->kvm->n_requested_mmu_pages) + vcpu->kvm->n_free_mmu_pages = vcpu->kvm->n_requested_mmu_pages; + else + vcpu->kvm->n_free_mmu_pages = vcpu->kvm->n_alloc_mmu_pages; /* * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64. * Therefore we need to allocate shadow page tables in the first diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 057a7f3..d2fd973 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -347,11 +347,14 @@ struct kvm_signal_mask { */ #define KVM_CAP_IRQCHIP 0 #define KVM_CAP_HLT 1 +#define KVM_CAP_MMU_SHADOW_CACHE_CONTROL 2 /* * ioctls for VM fds */ #define KVM_SET_MEMORY_REGION _IOW(KVMIO, 0x40, struct kvm_memory_region) +#define KVM_SET_NR_MMU_PAGES _IO(KVMIO, 0x44) +#define KVM_GET_NR_MMU_PAGES _IO(KVMIO, 0x45) /* * KVM_CREATE_VCPU receives as a parameter the vcpu slot, and returns * a vcpu fd. |