KVM: modify memslots layout in struct kvm

Have a pointer to an allocated region inside struct kvm.

[alex: fix ppc book 3s]

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

8 files changed, 60 insertions, 37 deletions

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index 5fdeec5fddcf..1ca1dbf48117 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -1377,12 +1377,14 @@ static void free_kvm(struct kvm *kvm)
 
 static void kvm_release_vm_pages(struct kvm *kvm)
 {
+        struct kvm_memslots *slots;
         struct kvm_memory_slot *memslot;
         int i, j;
         unsigned long base_gfn;
 
-        for (i = 0; i < kvm->nmemslots; i++) {
-                memslot = &kvm->memslots[i];
+        slots = kvm->memslots;
+        for (i = 0; i < slots->nmemslots; i++) {
+                memslot = &slots->memslots[i];
                 base_gfn = memslot->base_gfn;
 
                 for (j = 0; j < memslot->npages; j++) {
@@ -1802,7 +1804,7 @@ static int kvm_ia64_sync_dirty_log(struct kvm *kvm,
         if (log->slot >= KVM_MEMORY_SLOTS)
                 goto out;
 
-        memslot = &kvm->memslots[log->slot];
+        memslot = &kvm->memslots->memslots[log->slot];
         r = -ENOENT;
         if (!memslot->dirty_bitmap)
                 goto out;
@@ -1840,7 +1842,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
         /* If nothing is dirty, don't bother messing with page tables. */
         if (is_dirty) {
                 kvm_flush_remote_tlbs(kvm);
-                memslot = &kvm->memslots[log->slot];
+                memslot = &kvm->memslots->memslots[log->slot];
                 n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
                 memset(memslot->dirty_bitmap, 0, n);
         }
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 803505d3e455..bb8873dcb20f 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -865,7 +865,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
 
         /* If nothing is dirty, don't bother messing with page tables. */
         if (is_dirty) {
-                memslot = &kvm->memslots[log->slot];
+                memslot = &kvm->memslots->memslots[log->slot];
 
                 ga = memslot->base_gfn << PAGE_SHIFT;
                 ga_end = ga + (memslot->npages << PAGE_SHIFT);
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 4f499d7f7106..81f84d326a84 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -807,13 +807,14 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
 {
         int i, j;
         int retval = 0;
+        struct kvm_memslots *slots = kvm->memslots;
 
         /*
          * If mmap_sem isn't taken, we can look the memslots with only
          * the mmu_lock by skipping over the slots with userspace_addr == 0.
          */
-        for (i = 0; i < kvm->nmemslots; i++) {
-                struct kvm_memory_slot *memslot = &kvm->memslots[i];
+        for (i = 0; i < slots->nmemslots; i++) {
+                struct kvm_memory_slot *memslot = &slots->memslots[i];
                 unsigned long start = memslot->userspace_addr;
                 unsigned long end;
 
@@ -3021,8 +3022,8 @@ unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm)
         unsigned int nr_mmu_pages;
         unsigned int  nr_pages = 0;
 
-        for (i = 0; i < kvm->nmemslots; i++)
-                nr_pages += kvm->memslots[i].npages;
+        for (i = 0; i < kvm->memslots->nmemslots; i++)
+                nr_pages += kvm->memslots->memslots[i].npages;
 
         nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000;
         nr_mmu_pages = max(nr_mmu_pages,
@@ -3295,7 +3296,7 @@ static int count_rmaps(struct kvm_vcpu *vcpu)
         int i, j, k;
 
         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
-                struct kvm_memory_slot *m = &vcpu->kvm->memslots[i];
+                struct kvm_memory_slot *m = &vcpu->kvm->memslots->memslots[i];
                 struct kvm_rmap_desc *d;
 
                 for (j = 0; j < m->npages; ++j) {
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 74a66f0c00b4..18698799e365 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1503,8 +1503,8 @@ static void enter_pmode(struct kvm_vcpu *vcpu)
 static gva_t rmode_tss_base(struct kvm *kvm)
 {
         if (!kvm->arch.tss_addr) {
-                gfn_t base_gfn = kvm->memslots[0].base_gfn +
-                                 kvm->memslots[0].npages - 3;
+                gfn_t base_gfn = kvm->memslots->memslots[0].base_gfn +
+                                 kvm->memslots->memslots[0].npages - 3;
                 return base_gfn << PAGE_SHIFT;
         }
         return kvm->arch.tss_addr;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8798504ace11..3b81cb9da8b8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2427,7 +2427,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
                 spin_lock(&kvm->mmu_lock);
                 kvm_mmu_slot_remove_write_access(kvm, log->slot);
                 spin_unlock(&kvm->mmu_lock);
-                memslot = &kvm->memslots[log->slot];
+                memslot = &kvm->memslots->memslots[log->slot];
                 n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
                 memset(memslot->dirty_bitmap, 0, n);
         }
@@ -5223,7 +5223,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
                                 int user_alloc)
 {
         int npages = mem->memory_size >> PAGE_SHIFT;
-        struct kvm_memory_slot *memslot = &kvm->memslots[mem->slot];
+        struct kvm_memory_slot *memslot = &kvm->memslots->memslots[mem->slot];
 
         /*To keep backward compatibility with older userspace,
          *x86 needs to hanlde !user_alloc case.
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index bd5a616d9373..782bfb185f8a 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -150,14 +150,18 @@ struct kvm_irq_routing_table {};
 
 #endif
 
+struct kvm_memslots {
+        int nmemslots;
+        struct kvm_memory_slot memslots[KVM_MEMORY_SLOTS +
+                                        KVM_PRIVATE_MEM_SLOTS];
+};
+
 struct kvm {
         spinlock_t mmu_lock;
         spinlock_t requests_lock;
         struct rw_semaphore slots_lock;
         struct mm_struct *mm; /* userspace tied to this vm */
-        int nmemslots;
-        struct kvm_memory_slot memslots[KVM_MEMORY_SLOTS +
-                                        KVM_PRIVATE_MEM_SLOTS];
+        struct kvm_memslots *memslots;
 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
         u32 bsp_vcpu_id;
         struct kvm_vcpu *bsp_vcpu;
@@ -482,7 +486,7 @@ static inline void kvm_guest_exit(void)
 
 static inline int memslot_id(struct kvm *kvm, struct kvm_memory_slot *slot)
 {
-        return slot - kvm->memslots;
+        return slot - kvm->memslots->memslots;
 }
 
 static inline gpa_t gfn_to_gpa(gfn_t gfn)
diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
index 15147583abd1..bc697a66a883 100644
--- a/virt/kvm/iommu.c
+++ b/virt/kvm/iommu.c
@@ -76,10 +76,13 @@ unmap_pages:
 static int kvm_iommu_map_memslots(struct kvm *kvm)
 {
         int i, r = 0;
+        struct kvm_memslots *slots;
 
-        for (i = 0; i < kvm->nmemslots; i++) {
-                r = kvm_iommu_map_pages(kvm, kvm->memslots[i].base_gfn,
-                                        kvm->memslots[i].npages);
+        slots = kvm->memslots;
+
+        for (i = 0; i < slots->nmemslots; i++) {
+                r = kvm_iommu_map_pages(kvm, slots->memslots[i].base_gfn,
+                                        slots->memslots[i].npages);
                 if (r)
                         break;
         }
@@ -210,10 +213,13 @@ static void kvm_iommu_put_pages(struct kvm *kvm,
 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 {
         int i;
+        struct kvm_memslots *slots;
+
+        slots = kvm->memslots;
 
-        for (i = 0; i < kvm->nmemslots; i++) {
-                kvm_iommu_put_pages(kvm, kvm->memslots[i].base_gfn,
-                                    kvm->memslots[i].npages);
+        for (i = 0; i < slots->nmemslots; i++) {
+                kvm_iommu_put_pages(kvm, slots->memslots[i].base_gfn,
+                                    slots->memslots[i].npages);
         }
 
         return 0;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index bc23b8e0609b..86dd8f3d29c9 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -375,12 +375,16 @@ static struct kvm *kvm_create_vm(void)
         INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 #endif
 
+        r = -ENOMEM;
+        kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
+        if (!kvm->memslots)
+                goto out_err;
+
 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
-        if (!page) {
-                r = -ENOMEM;
+        if (!page)
                 goto out_err;
-        }
+
         kvm->coalesced_mmio_ring =
                         (struct kvm_coalesced_mmio_ring *)page_address(page);
 #endif
@@ -416,6 +420,7 @@ out:
 out_err:
         hardware_disable_all();
 out_err_nodisable:
+        kfree(kvm->memslots);
         kfree(kvm);
         return ERR_PTR(r);
 }
@@ -450,9 +455,12 @@ static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 void kvm_free_physmem(struct kvm *kvm)
 {
         int i;
+        struct kvm_memslots *slots = kvm->memslots;
+
+        for (i = 0; i < slots->nmemslots; ++i)
+                kvm_free_physmem_slot(&slots->memslots[i], NULL);
 
-        for (i = 0; i < kvm->nmemslots; ++i)
-                kvm_free_physmem_slot(&kvm->memslots[i], NULL);
+        kfree(kvm->memslots);
 }
 
 static void kvm_destroy_vm(struct kvm *kvm)
@@ -533,7 +541,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
                 goto out;
 
-        memslot = &kvm->memslots[mem->slot];
+        memslot = &kvm->memslots->memslots[mem->slot];
         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
         npages = mem->memory_size >> PAGE_SHIFT;
 
@@ -554,7 +562,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
         /* Check for overlaps */
         r = -EEXIST;
         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
-                struct kvm_memory_slot *s = &kvm->memslots[i];
+                struct kvm_memory_slot *s = &kvm->memslots->memslots[i];
 
                 if (s == memslot || !s->npages)
                         continue;
@@ -656,8 +664,8 @@ skip_lpage:
                 kvm_arch_flush_shadow(kvm);
 
         spin_lock(&kvm->mmu_lock);
-        if (mem->slot >= kvm->nmemslots)
-                kvm->nmemslots = mem->slot + 1;
+        if (mem->slot >= kvm->memslots->nmemslots)
+                kvm->memslots->nmemslots = mem->slot + 1;
 
         *memslot = new;
         spin_unlock(&kvm->mmu_lock);
@@ -727,7 +735,7 @@ int kvm_get_dirty_log(struct kvm *kvm,
         if (log->slot >= KVM_MEMORY_SLOTS)
                 goto out;
 
-        memslot = &kvm->memslots[log->slot];
+        memslot = &kvm->memslots->memslots[log->slot];
         r = -ENOENT;
         if (!memslot->dirty_bitmap)
                 goto out;
@@ -781,9 +789,10 @@ EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
 {
         int i;
+        struct kvm_memslots *slots = kvm->memslots;
 
-        for (i = 0; i < kvm->nmemslots; ++i) {
-                struct kvm_memory_slot *memslot = &kvm->memslots[i];
+        for (i = 0; i < slots->nmemslots; ++i) {
+                struct kvm_memory_slot *memslot = &slots->memslots[i];
 
                 if (gfn >= memslot->base_gfn
                     && gfn < memslot->base_gfn + memslot->npages)
@@ -802,10 +811,11 @@ struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 {
         int i;
+        struct kvm_memslots *slots = kvm->memslots;
 
         gfn = unalias_gfn(kvm, gfn);
         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
-                struct kvm_memory_slot *memslot = &kvm->memslots[i];
+                struct kvm_memory_slot *memslot = &slots->memslots[i];
 
                 if (gfn >= memslot->base_gfn
                     && gfn < memslot->base_gfn + memslot->npages)