[libvirt] [PATCH 8/8] qemu ns: Create chardev backends more frequently

[John Ferlan]

On 06/22/2017 12:18 PM, Michal Privoznik wrote:
> Currently, the only type of chardev that we create the backend
> for in the namespace is type='dev'. This is not enough, other
> backends might have files under /dev too. For instance channels
> might have a unix socket under /dev (well, bind mounted under
> /dev from a different place).
> 
> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
> ---
>  src/qemu/qemu_domain.c | 25 +++++++++++++++++--------
>  1 file changed, 17 insertions(+), 8 deletions(-)
> 
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
> index 51779c535..65eec26dd 100644
> --- a/src/qemu/qemu_domain.c
> +++ b/src/qemu/qemu_domain.c
> @@ -7732,7 +7732,7 @@ qemuDomainCreateDeviceRecursive(const char *device,
>  
>      isLink = S_ISLNK(sb.st_mode);
>      isDev = S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode);
> -    isReg = S_ISREG(sb.st_mode);
> +    isReg = S_ISREG(sb.st_mode) || S_ISFIFO(sb.st_mode) || S_ISSOCK(sb.st_mode);
>  
>      /* Here, @device might be whatever path in the system. We
>       * should create the path in the namespace iff it's "/dev"
> @@ -8129,11 +8129,17 @@ qemuDomainSetupChardev(virDomainDefPtr def ATTRIBUTE_UNUSED,
>                         void *opaque)
>  {
>      const struct qemuDomainCreateDeviceData *data = opaque;
> +    const char *path = NULL;
>  
> -    if (dev->source->type != VIR_DOMAIN_CHR_TYPE_DEV)
> +    if (!(path = virDomainChrSourceDefPath(dev->source)))
>          return 0;
>  
> -    return qemuDomainCreateDevice(dev->source->data.file.path, data, false);
> +    /* Socket created by qemu. It doesn't exist upfront. */
> +    if (dev->source->type == VIR_DOMAIN_CHR_TYPE_UNIX &&
> +        dev->source->data.nix.listen)
> +        return 0;
> +
> +    return qemuDomainCreateDevice(path, data, true);
>  }
>  
>  
> @@ -8531,7 +8537,7 @@ qemuDomainAttachDeviceMknodHelper(pid_t pid ATTRIBUTE_UNUSED,
>      bool delDevice = false;
>      bool isLink = S_ISLNK(data->sb.st_mode);
>      bool isDev = S_ISCHR(data->sb.st_mode) || S_ISBLK(data->sb.st_mode);
> -    bool isReg = S_ISREG(data->sb.st_mode);
> +    bool isReg = S_ISREG(data->sb.st_mode) || S_ISFIFO(data->sb.st_mode) || S_ISSOCK(data->sb.st_mode);
>  
>      qemuSecurityPostFork(data->driver->securityManager);
>  
> @@ -8576,7 +8582,7 @@ qemuDomainAttachDeviceMknodHelper(pid_t pid ATTRIBUTE_UNUSED,
>           * as its backing chain. This might however clash here.
>           * Therefore do the cleanup here. */
>          if (umount(data->file) < 0 &&
> -            errno != ENOENT) {
> +            errno != ENOENT && errno != EINVAL) {

Is this something that should be separate or as a result of the current
changes?  Should it go with the previous patch since that's where it's
introduced?

Reviewed-by: John Ferlan <jferlan at redhat.com>

John

>              virReportSystemError(errno,
>                                   _("Unable to umount %s"),
>                                   data->file);
> @@ -8685,7 +8691,7 @@ qemuDomainAttachDeviceMknodRecursive(virQEMUDriverPtr driver,
>      }
>  
>      isLink = S_ISLNK(data.sb.st_mode);
> -    isReg = S_ISREG(data.sb.st_mode);
> +    isReg = S_ISREG(data.sb.st_mode) || S_ISFIFO(data.sb.st_mode) || S_ISSOCK(data.sb.st_mode);
>  
>      if (isReg && STRPREFIX(file, DEVPREFIX)) {
>          cfg = virQEMUDriverGetConfig(driver);
> @@ -9077,10 +9083,13 @@ qemuDomainNamespaceSetupChardev(virQEMUDriverPtr driver,
>      if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
>          return 0;
>  
> -    if (chr->source->type != VIR_DOMAIN_CHR_TYPE_DEV)
> +    if (!(path = virDomainChrSourceDefPath(chr->source)))
>          return 0;
>  
> -    path = chr->source->data.file.path;
> +    /* Socket created by qemu. It doesn't exist upfront. */
> +    if (chr->source->type == VIR_DOMAIN_CHR_TYPE_UNIX &&
> +        chr->source->data.nix.listen)
> +        return 0;
>  
>      cfg = virQEMUDriverGetConfig(driver);
>      if (qemuDomainGetPreservedMounts(cfg, vm,
>