[libvirt] [PATCH 5/6] qemu: Move the shared disk adding and sgio setting prior to attaching

[John Ferlan]

On 02/13/2013 09:58 AM, Osier Yang wrote:
> The disk def could be free'ed by qemuDomainChangeEjectableMedia,
> which can thus cause crash if we reference the disk pointer. On
> the other hand, we have to remove the added shared disk entry from
> the table on error codepath.
> ---
>  src/qemu/qemu_driver.c |   25 +++++++++++--------------
>  1 files changed, 11 insertions(+), 14 deletions(-)
> 
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index 527c671..48852ad 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -5837,6 +5837,12 @@ qemuDomainAttachDeviceDiskLive(virConnectPtr conn,
>          goto end;
>      }
>  
> +    if (qemuAddSharedDisk(driver, disk, vm->def->name) < 0)
> +        goto end;
> +
> +    if (qemuSetUnprivSGIO(disk) < 0)
> +        goto end;
> +
>      if (qemuDomainDetermineDiskChain(driver, disk, false) < 0)
>          goto end;
>  
> @@ -5850,6 +5856,7 @@ qemuDomainAttachDeviceDiskLive(virConnectPtr conn,
>          if (qemuSetupDiskCgroup(vm, cgroup, disk) < 0)
>              goto end;
>      }
> +
>      switch (disk->device)  {
>      case VIR_DOMAIN_DISK_DEVICE_CDROM:
>      case VIR_DOMAIN_DISK_DEVICE_FLOPPY:
> @@ -5888,16 +5895,9 @@ qemuDomainAttachDeviceDiskLive(virConnectPtr conn,
>                       NULLSTR(disk->src));
>      }
>  
> -    if (ret == 0) {
> -        if (qemuAddSharedDisk(driver, disk, vm->def->name) < 0)
> -            VIR_WARN("Failed to add disk '%s' to shared disk table",
> -                     disk->src);
> -
> -        if (qemuSetUnprivSGIO(disk) < 0)
> -            VIR_WARN("Failed to set unpriv_sgio of disk '%s'", disk->src);
> -    }
> -
>  end:
> +    if (ret != 0)
> +        ignore_value(qemuRemoveSharedDisk(driver, disk, vm->def->name));

I can understand why not to log here - you didn't add and I think we
message those cases, so why say we couldn't remove if we couldn't add.

>      if (cgroup)
>          virCgroupFree(&cgroup);
>      return ret;
> @@ -6012,11 +6012,8 @@ qemuDomainDetachDeviceDiskLive(virQEMUDriverPtr driver,
>          break;
>      }
>  
> -    if (ret == 0) {
> -        if (qemuRemoveSharedDisk(driver, disk, vm->def->name) < 0)
> -             VIR_WARN("Failed to remove disk '%s' from shared disk table",
> -                      disk->src);
> -    }
> +    if (ret == 0)
> +        ignore_value(qemuRemoveSharedDisk(driver, disk, vm->def->name));

However, it seems we should log this.
>  
>      return ret;
>  }
>