KVM: Clean up vm creation and release

IA64 support forces us to abstract the allocation of the kvm structure.
But instead of mixing this up with arch-specific initialization and
doing the same on destruction, split both steps. This allows to move
generic destruction calls into generic code.

It also fixes error clean-up on failures of kvm_create_vm for IA64.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

7 files changed, 49 insertions, 72 deletions

diff --git a/arch/ia64/include/asm/kvm_host.h b/arch/ia64/include/asm/kvm_host.h
index 2f229e5de498..2689ee54a1c9 100644
--- a/arch/ia64/include/asm/kvm_host.h
+++ b/arch/ia64/include/asm/kvm_host.h
@@ -590,6 +590,10 @@ int kvm_emulate_halt(struct kvm_vcpu *vcpu);
 int kvm_pal_emul(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run);
 void kvm_sal_emul(struct kvm_vcpu *vcpu);
 
+#define __KVM_HAVE_ARCH_VM_ALLOC 1
+struct kvm *kvm_arch_alloc_vm(void);
+void kvm_arch_free_vm(struct kvm *kvm);
+
 #endif /* __ASSEMBLY__*/
 
 #endif
diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index f56a6316e134..48a48bdc59c3 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -749,7 +749,7 @@ out:
         return r;
 }
 
-static struct kvm *kvm_alloc_kvm(void)
+struct kvm *kvm_arch_alloc_vm(void)
 {
 
         struct kvm *kvm;
@@ -760,7 +760,7 @@ static struct kvm *kvm_alloc_kvm(void)
         vm_base = __get_free_pages(GFP_KERNEL, get_order(KVM_VM_DATA_SIZE));
 
         if (!vm_base)
-                return ERR_PTR(-ENOMEM);
+                return NULL;
 
         memset((void *)vm_base, 0, KVM_VM_DATA_SIZE);
         kvm = (struct kvm *)(vm_base +
@@ -806,10 +806,12 @@ static void kvm_build_io_pmt(struct kvm *kvm)
 #define GUEST_PHYSICAL_RR4      0x2739
 #define VMM_INIT_RR             0x1660
 
-static void kvm_init_vm(struct kvm *kvm)
+int kvm_arch_init_vm(struct kvm *kvm)
 {
         BUG_ON(!kvm);
 
+        kvm->arch.is_sn2 = ia64_platform_is("sn2");
+
         kvm->arch.metaphysical_rr0 = GUEST_PHYSICAL_RR0;
         kvm->arch.metaphysical_rr4 = GUEST_PHYSICAL_RR4;
         kvm->arch.vmm_init_rr = VMM_INIT_RR;
@@ -823,21 +825,8 @@ static void kvm_init_vm(struct kvm *kvm)
 
         /* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
         set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap);
-}
-
-struct  kvm *kvm_arch_create_vm(void)
-{
-        struct kvm *kvm = kvm_alloc_kvm();
-
-        if (IS_ERR(kvm))
-                return ERR_PTR(-ENOMEM);
-
-        kvm->arch.is_sn2 = ia64_platform_is("sn2");
-
-        kvm_init_vm(kvm);
-
-        return kvm;
 
+        return 0;
 }
 
 static int kvm_vm_ioctl_get_irqchip(struct kvm *kvm,
@@ -1357,7 +1346,7 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
         return -EINVAL;
 }
 
-static void free_kvm(struct kvm *kvm)
+void kvm_arch_free_vm(struct kvm *kvm)
 {
         unsigned long vm_base = kvm->arch.vm_base;
 
@@ -1399,9 +1388,6 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 #endif
         kfree(kvm->arch.vioapic);
         kvm_release_vm_pages(kvm);
-        kvm_free_physmem(kvm);
-        cleanup_srcu_struct(&kvm->srcu);
-        free_kvm(kvm);
 }
 
 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 38f756f25053..99758460efde 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -145,18 +145,12 @@ void kvm_arch_check_processor_compat(void *rtn)
         *(int *)rtn = kvmppc_core_check_processor_compat();
 }
 
-struct kvm *kvm_arch_create_vm(void)
+int kvm_arch_init_vm(struct kvm *kvm)
 {
-        struct kvm *kvm;
-
-        kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
-        if (!kvm)
-                return ERR_PTR(-ENOMEM);
-
-        return kvm;
+        return 0;
 }
 
-static void kvmppc_free_vcpus(struct kvm *kvm)
+void kvm_arch_destroy_vm(struct kvm *kvm)
 {
         unsigned int i;
         struct kvm_vcpu *vcpu;
@@ -176,14 +170,6 @@ void kvm_arch_sync_events(struct kvm *kvm)
 {
 }
 
-void kvm_arch_destroy_vm(struct kvm *kvm)
-{
-        kvmppc_free_vcpus(kvm);
-        kvm_free_physmem(kvm);
-        cleanup_srcu_struct(&kvm->srcu);
-        kfree(kvm);
-}
-
 int kvm_dev_ioctl_check_extension(long ext)
 {
         int r;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 985d825494f1..bade533ba288 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -164,24 +164,18 @@ long kvm_arch_vm_ioctl(struct file *filp,
         return r;
 }
 
-struct kvm *kvm_arch_create_vm(void)
+int kvm_arch_init_vm(struct kvm *kvm)
 {
-        struct kvm *kvm;
         int rc;
         char debug_name[16];
 
         rc = s390_enable_sie();
         if (rc)
-                goto out_nokvm;
-
-        rc = -ENOMEM;
-        kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
-        if (!kvm)
-                goto out_nokvm;
+                goto out_err;
 
         kvm->arch.sca = (struct sca_block *) get_zeroed_page(GFP_KERNEL);
         if (!kvm->arch.sca)
-                goto out_nosca;
+                goto out_err;
 
         sprintf(debug_name, "kvm-%u", current->pid);
 
@@ -195,13 +189,11 @@ struct kvm *kvm_arch_create_vm(void)
         debug_register_view(kvm->arch.dbf, &debug_sprintf_view);
         VM_EVENT(kvm, 3, "%s", "vm created");
 
-        return kvm;
+        return 0;
 out_nodbf:
         free_page((unsigned long)(kvm->arch.sca));
-out_nosca:
-        kfree(kvm);
-out_nokvm:
-        return ERR_PTR(rc);
+out_err:
+        return rc;
 }
 
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
@@ -240,11 +232,8 @@ void kvm_arch_sync_events(struct kvm *kvm)
 void kvm_arch_destroy_vm(struct kvm *kvm)
 {
         kvm_free_vcpus(kvm);
-        kvm_free_physmem(kvm);
         free_page((unsigned long)(kvm->arch.sca));
         debug_unregister(kvm->arch.dbf);
-        cleanup_srcu_struct(&kvm->srcu);
-        kfree(kvm);
 }
 
 /* Section: vcpu related */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5daead833669..b7ee61d5bc81 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5961,13 +5961,8 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
         free_page((unsigned long)vcpu->arch.pio_data);
 }
 
-struct  kvm *kvm_arch_create_vm(void)
+int kvm_arch_init_vm(struct kvm *kvm)
 {
-        struct kvm *kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
-
-        if (!kvm)
-                return ERR_PTR(-ENOMEM);
-
         INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
         INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
 
@@ -5976,7 +5971,7 @@ struct  kvm *kvm_arch_create_vm(void)
 
         spin_lock_init(&kvm->arch.tsc_write_lock);
 
-        return kvm;
+        return 0;
 }
 
 static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
@@ -6021,13 +6016,10 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
         kfree(kvm->arch.vpic);
         kfree(kvm->arch.vioapic);
         kvm_free_vcpus(kvm);
-        kvm_free_physmem(kvm);
         if (kvm->arch.apic_access_page)
                 put_page(kvm->arch.apic_access_page);
         if (kvm->arch.ept_identity_pagetable)
                 put_page(kvm->arch.ept_identity_pagetable);
-        cleanup_srcu_struct(&kvm->srcu);
-        kfree(kvm);
 }
 
 int kvm_arch_prepare_memory_region(struct kvm *kvm,
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index bcf71c7730f0..2d63f2c0137c 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -16,6 +16,7 @@
 #include <linux/mm.h>
 #include <linux/preempt.h>
 #include <linux/msi.h>
+#include <linux/slab.h>
 #include <asm/signal.h>
 
 #include <linux/kvm.h>
@@ -441,7 +442,19 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu);
 
 void kvm_free_physmem(struct kvm *kvm);
 
-struct  kvm *kvm_arch_create_vm(void);
+#ifndef __KVM_HAVE_ARCH_VM_ALLOC
+static inline struct kvm *kvm_arch_alloc_vm(void)
+{
+        return kzalloc(sizeof(struct kvm), GFP_KERNEL);
+}
+
+static inline void kvm_arch_free_vm(struct kvm *kvm)
+{
+        kfree(kvm);
+}
+#endif
+
+int kvm_arch_init_vm(struct kvm *kvm);
 void kvm_arch_destroy_vm(struct kvm *kvm);
 void kvm_free_all_assigned_devices(struct kvm *kvm);
 void kvm_arch_sync_events(struct kvm *kvm);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index fce0578eab0e..4023264c4cd5 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -383,11 +383,15 @@ static int kvm_init_mmu_notifier(struct kvm *kvm)
 
 static struct kvm *kvm_create_vm(void)
 {
-        int r = 0, i;
-        struct kvm *kvm = kvm_arch_create_vm();
+        int r, i;
+        struct kvm *kvm = kvm_arch_alloc_vm();
 
-        if (IS_ERR(kvm))
-                goto out;
+        if (!kvm)
+                return ERR_PTR(-ENOMEM);
+
+        r = kvm_arch_init_vm(kvm);
+        if (r)
+                goto out_err_nodisable;
 
         r = hardware_enable_all();
         if (r)
@@ -427,7 +431,7 @@ static struct kvm *kvm_create_vm(void)
         spin_lock(&kvm_lock);
         list_add(&kvm->vm_list, &vm_list);
         spin_unlock(&kvm_lock);
-out:
+
         return kvm;
 
 out_err:
@@ -438,7 +442,7 @@ out_err_nodisable:
         for (i = 0; i < KVM_NR_BUSES; i++)
                 kfree(kvm->buses[i]);
         kfree(kvm->memslots);
-        kfree(kvm);
+        kvm_arch_free_vm(kvm);
         return ERR_PTR(r);
 }
 
@@ -512,6 +516,9 @@ static void kvm_destroy_vm(struct kvm *kvm)
         kvm_arch_flush_shadow(kvm);
 #endif
         kvm_arch_destroy_vm(kvm);
+        kvm_free_physmem(kvm);
+        cleanup_srcu_struct(&kvm->srcu);
+        kvm_arch_free_vm(kvm);
         hardware_disable_all();
         mmdrop(mm);
 }