[v3] KVM: Dirty ring support (QEMU part)

[PATCH RFC v3 03/11] KVM: Fixup kvm_log_clear_one_slot() ioctl return check

Posted by Peter Xu 5 years, 8 months ago

kvm_vm_ioctl() handles the errno trick already for ioctl() on
returning -1 for errors.  Fix this.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 accel/kvm/kvm-all.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index d06cc04079..6e015aa2d4 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -699,14 +699,13 @@ static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
     d.num_pages = bmap_npages;
     d.slot = mem->slot | (as_id << 16);
 
-    if (kvm_vm_ioctl(s, KVM_CLEAR_DIRTY_LOG, &d) == -1) {
-        ret = -errno;
+    ret = kvm_vm_ioctl(s, KVM_CLEAR_DIRTY_LOG, &d);
+    if (ret) {
         error_report("%s: KVM_CLEAR_DIRTY_LOG failed, slot=%d, "
                      "start=0x%"PRIx64", size=0x%"PRIx32", errno=%d",
                      __func__, d.slot, (uint64_t)d.first_page,
                      (uint32_t)d.num_pages, ret);
     } else {
-        ret = 0;
         trace_kvm_clear_dirty_log(d.slot, d.first_page, d.num_pages);
     }
 
-- 
2.26.2

Re: [PATCH RFC v3 03/11] KVM: Fixup kvm_log_clear_one_slot() ioctl return check

Posted by Philippe Mathieu-Daudé 5 years, 8 months ago

On 5/24/20 1:20 AM, Peter Xu wrote:
> kvm_vm_ioctl() handles the errno trick already for ioctl() on
> returning -1 for errors.  Fix this.
> 
> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  accel/kvm/kvm-all.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index d06cc04079..6e015aa2d4 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -699,14 +699,13 @@ static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
>      d.num_pages = bmap_npages;
>      d.slot = mem->slot | (as_id << 16);
>  
> -    if (kvm_vm_ioctl(s, KVM_CLEAR_DIRTY_LOG, &d) == -1) {
> -        ret = -errno;
> +    ret = kvm_vm_ioctl(s, KVM_CLEAR_DIRTY_LOG, &d);
> +    if (ret) {
>          error_report("%s: KVM_CLEAR_DIRTY_LOG failed, slot=%d, "
>                       "start=0x%"PRIx64", size=0x%"PRIx32", errno=%d",
>                       __func__, d.slot, (uint64_t)d.first_page,
>                       (uint32_t)d.num_pages, ret);
>      } else {
> -        ret = 0;
>          trace_kvm_clear_dirty_log(d.slot, d.first_page, d.num_pages);
>      }
>  
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>