[CRIU] [PATCH v5 16/33] files: Add fdinfo_list_entry::stage

[Kirill Tkhai]

On 18.01.2017 11:43, Pavel Emelyanov wrote:
> On 12/26/2016 05:27 PM, Kirill Tkhai wrote:
>> Add fle open stages. Set a stage after every operation.
>>
>> v2: Do not merge filetype specific state with generic.
>>
>> Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
>> ---
>>  criu/files.c         |   13 ++++++++++---
>>  criu/include/files.h |    9 +++++++++
>>  2 files changed, 19 insertions(+), 3 deletions(-)
>>
>> diff --git a/criu/files.c b/criu/files.c
>> index 87d8fc655..8e04309b6 100644
>> --- a/criu/files.c
>> +++ b/criu/files.c
>> @@ -1005,12 +1005,16 @@ static int post_open_fd(int pid, struct fdinfo_list_entry *fle)
>>  			return -1;
>>  		}
>>  		if (!is_service_fd(fle->fe->fd, CTL_TTY_OFF))
>> -			return 0;
>> +			goto out;
>>  	}
>>  
>>  	if (!d->ops->post_open)
>> -		return 0;
>> -	return d->ops->post_open(d, fle->fe->fd);
>> +		goto out;
>> +	if (d->ops->post_open(d, fle->fe->fd))
>> +		return -1;
>> +out:
>> +	fle->stage = FLE_RESTORED;
>> +	return 0;
>>  }
>>  
>>  
>> @@ -1058,6 +1062,9 @@ static int open_fd(int pid, struct fdinfo_list_entry *fle)
>>  		return -1;
>>  	}
>>  
>> +	if (fle->stage < FLE_OPEN)
> 
> Why is this if here?

I supposed, there may be file types, which would need to advance their state
more, that to FLE_OPEN. But there is no one no.

If you want, I may do patch, which will delete this and below, on top of the series.

> 
>> +		fle->stage = FLE_OPEN;
>> +
>>  	return serve_out_fd(pid, fle->fe->fd, d);
>>  }
>>  
>> diff --git a/criu/include/files.h b/criu/include/files.h
>> index 1b44960de..5fffed6a8 100644
>> --- a/criu/include/files.h
>> +++ b/criu/include/files.h
>> @@ -64,6 +64,13 @@ extern int fill_fdlink(int lfd, const struct fd_parms *p, struct fd_link *link);
>>  
>>  struct file_desc;
>>  
>> +enum {
>> +	FLE_INITIALIZED,
>> +	FLE_OPEN,
>> +	FLE_RESTORING,
> 
> State not used in this set.

It's aimed for the future using for file types, which need a intermediate state. But, correctly,
it's not used in this set.


>> +	FLE_RESTORED,
>> +};
>> +
>>  struct fdinfo_list_entry {
>>  	struct list_head	desc_list;	/* To chain on  @fd_info_head */
>>  	struct file_desc	*desc;		/* Associated file descriptor */
>> @@ -72,6 +79,7 @@ struct fdinfo_list_entry {
>>  	int			pid;
>>  	FdinfoEntry		*fe;
>>  	u8			received:1;
>> +	u8			stage:3;
>>  };
>>  
>>  static inline void fle_init(struct fdinfo_list_entry *fle, int pid, FdinfoEntry *fe)
>> @@ -79,6 +87,7 @@ static inline void fle_init(struct fdinfo_list_entry *fle, int pid, FdinfoEntry
>>  	fle->pid = pid;
>>  	fle->fe = fe;
>>  	fle->received = 0;
>> +	fle->stage = FLE_INITIALIZED;
>>  }
>>  
>>  /* reports whether fd_a takes prio over fd_b */
>>
>> .
>>
>