Re: [PATCH v2] KVM: Clean up vm creation and release

Jan Kiszka
2010-11-10T10:18:02Z

Am 10.11.2010 10:45, Avi Kivity wrote:
> On 11/10/2010 11:30 AM, Jan Kiszka wrote:
>> Am 10.11.2010 10:17, Avi Kivity wrote:
>>> On 11/09/2010 11:01 PM, Alexander Graf wrote:
>>>> On 09.11.2010, at 17:02, Jan Kiszka wrote:
>>>>
>>>>> 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-kv7WeFo6aLtBDgjK7y7TUQ@public.gmane.org>
>>>>> ---
>>>>>
>>>>> Changes in v2:
>>>>> - Fixed s390 conversion and added linux/slab.h
>>>>> as remarked by Christian (thanks!)
>>>>>
>>>>> arch/ia64/include/asm/kvm_host.h | 4 ++++
>>>>> arch/ia64/kvm/kvm-ia64.c | 28 +++++++---------------------
>>>>> arch/powerpc/kvm/powerpc.c | 20 +++-----------------
>>>>> arch/s390/kvm/kvm-s390.c | 23 ++++++-----------------
>>>>> arch/x86/kvm/x86.c | 12 ++----------
>>>>> include/linux/kvm_host.h | 15 ++++++++++++++-
>>>>> virt/kvm/kvm_main.c | 19 +++++++++++++------
>>>>> 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 2f229e5..2689ee5 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 f56a631..48a48bd 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 38f756f..ce3dd65 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 *)
>>>>
>>>> Eh, no. This doesn't compile :).
>>>
>>> What's the problem? lack of a formal argument?
>>
>> The unnamed argument is referenced as 'kvm' in this function.
>
> It isn't referenced:
>
>> int kvm_arch_init_vm(struct kvm *)
>> {
>> return 0;
>> }
>

Indeed. Anyway, this wasn't intended (even more if some compiler
versions/settings dislike it).

Jan

--
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