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

[Michal Privoznik]

On 06/28/2017 01:00 AM, John Ferlan wrote:
> 
> 
> 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?

It's a result of this change. umout() is not consistent in returned
errno. Depending on type of file that we wanted to umount we might get
either ENOENT or EINVAL.

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

Thanks.

Michal