Message ID | 1410413886-32213-4-git-send-email-tangchen@cn.fujitsu.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Il 11/09/2014 07:38, Tang Chen ha scritto: > In init_rmode_identity_map(), there two variables indicating the return > value, r and ret, and it return 0 on error, 1 on success. The function > is only called by vmx_create_vcpu(), and r is redundant. > > This patch removes the redundant variable r, and make init_rmode_identity_map() > return 0 on success, -errno on failure. > > Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> > --- > arch/x86/kvm/vmx.c | 25 +++++++++++-------------- > 1 file changed, 11 insertions(+), 14 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 953d529..63c4c3e 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -3939,45 +3939,42 @@ out: > > static int init_rmode_identity_map(struct kvm *kvm) > { > - int i, idx, r, ret = 0; > + int i, idx, ret = 0; > pfn_t identity_map_pfn; > u32 tmp; > > if (!enable_ept) > - return 1; > + return 0; > > /* Protect kvm->arch.ept_identity_pagetable_done. */ > mutex_lock(&kvm->slots_lock); > > - if (likely(kvm->arch.ept_identity_pagetable_done)) { > - ret = 1; > + if (likely(kvm->arch.ept_identity_pagetable_done)) > goto out2; > - } > > identity_map_pfn = kvm->arch.ept_identity_map_addr >> PAGE_SHIFT; > > - r = alloc_identity_pagetable(kvm); > - if (r) > + ret = alloc_identity_pagetable(kvm); > + if (ret) > goto out2; > > idx = srcu_read_lock(&kvm->srcu); > - r = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE); > - if (r < 0) > + ret = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE); > + if (ret) > goto out; > /* Set up identity-mapping pagetable for EPT in real mode */ > for (i = 0; i < PT32_ENT_PER_PAGE; i++) { > tmp = (i << 22) + (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | > _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE); > - r = kvm_write_guest_page(kvm, identity_map_pfn, > + ret = kvm_write_guest_page(kvm, identity_map_pfn, > &tmp, i * sizeof(tmp), sizeof(tmp)); > - if (r < 0) > + if (ret) > goto out; > } > kvm->arch.ept_identity_pagetable_done = true; > - ret = 1; > + > out: > srcu_read_unlock(&kvm->srcu, idx); > - > out2: > mutex_unlock(&kvm->slots_lock); > return ret; > @@ -7645,7 +7642,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) > kvm->arch.ept_identity_map_addr = > VMX_EPT_IDENTITY_PAGETABLE_ADDR; > err = -ENOMEM; > - if (!init_rmode_identity_map(kvm)) > + if (init_rmode_identity_map(kvm)) Please add "< 0" here. I would also consider setting err to the return value of init_rmode_identity_map, and initializing it to -ENOMEM only after the "if". Paolo > goto free_vmcs; -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/11/2014 05:17 PM, Paolo Bonzini wrote: > ...... > @@ -7645,7 +7642,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) > kvm->arch.ept_identity_map_addr = > VMX_EPT_IDENTITY_PAGETABLE_ADDR; > err = -ENOMEM; > - if (!init_rmode_identity_map(kvm)) > + if (init_rmode_identity_map(kvm)) > Please add "< 0" here. I would also consider setting err to the return > value of init_rmode_identity_map, and initializing it to -ENOMEM only > after the "if". > I'd like to move err = -ENOMEM to the following place: vmx_create_vcpu() { ...... err = kvm_vcpu_init(&vmx->vcpu, kvm, id); if (err) goto free_vcpu; err = -ENOMEM; ---------------------- move it here vmx->guest_msrs = kmalloc(PAGE_SIZE, GFP_KERNEL); .... vmx->loaded_vmcs->vmcs = alloc_vmcs(); .... } So that it can be used to handle the next two memory allocation error. Thanks. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 953d529..63c4c3e 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3939,45 +3939,42 @@ out: static int init_rmode_identity_map(struct kvm *kvm) { - int i, idx, r, ret = 0; + int i, idx, ret = 0; pfn_t identity_map_pfn; u32 tmp; if (!enable_ept) - return 1; + return 0; /* Protect kvm->arch.ept_identity_pagetable_done. */ mutex_lock(&kvm->slots_lock); - if (likely(kvm->arch.ept_identity_pagetable_done)) { - ret = 1; + if (likely(kvm->arch.ept_identity_pagetable_done)) goto out2; - } identity_map_pfn = kvm->arch.ept_identity_map_addr >> PAGE_SHIFT; - r = alloc_identity_pagetable(kvm); - if (r) + ret = alloc_identity_pagetable(kvm); + if (ret) goto out2; idx = srcu_read_lock(&kvm->srcu); - r = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE); - if (r < 0) + ret = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE); + if (ret) goto out; /* Set up identity-mapping pagetable for EPT in real mode */ for (i = 0; i < PT32_ENT_PER_PAGE; i++) { tmp = (i << 22) + (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE); - r = kvm_write_guest_page(kvm, identity_map_pfn, + ret = kvm_write_guest_page(kvm, identity_map_pfn, &tmp, i * sizeof(tmp), sizeof(tmp)); - if (r < 0) + if (ret) goto out; } kvm->arch.ept_identity_pagetable_done = true; - ret = 1; + out: srcu_read_unlock(&kvm->srcu, idx); - out2: mutex_unlock(&kvm->slots_lock); return ret; @@ -7645,7 +7642,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) kvm->arch.ept_identity_map_addr = VMX_EPT_IDENTITY_PAGETABLE_ADDR; err = -ENOMEM; - if (!init_rmode_identity_map(kvm)) + if (init_rmode_identity_map(kvm)) goto free_vmcs; }
In init_rmode_identity_map(), there two variables indicating the return value, r and ret, and it return 0 on error, 1 on success. The function is only called by vmx_create_vcpu(), and r is redundant. This patch removes the redundant variable r, and make init_rmode_identity_map() return 0 on success, -errno on failure. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> --- arch/x86/kvm/vmx.c | 25 +++++++++++-------------- 1 file changed, 11 insertions(+), 14 deletions(-)