[PATCH] nbd:clear NBD_BOUND flag when NBD connection is closed

[Adriana Kobylak]

Adding Josef (updated email address in the maintainers file).

On 2018-12-13 08:21, Adriana Kobylak wrote:
> On 2018-12-11 00:17, medadyoung at gmail.com wrote:
>> From: Medad <medadyoung at gmail.com>
>> 
>>     If we do NOT clear NBD_BOUND flag when NBD connection is closed,
>>     then the original NBD device could not be used again.
>> 
>> Signed-off-by: Medad <medadyoung at gmail.com>
> 
> Tested on Witherspoon (OpenPOWER P9 with AST2500) and verified with
> this patch that the NBD device could be disconnected/reconnected.
> 
> Tested by: Adriana Kobylak <anoo at linux.ibm.com>
> 
>> ---
>>  drivers/block/nbd.c | 11 ++++++++---
>>  1 file changed, 8 insertions(+), 3 deletions(-)
>> 
>> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
>> index 64278f4..5c88490 100644
>> --- a/drivers/block/nbd.c
>> +++ b/drivers/block/nbd.c
>> @@ -277,10 +277,14 @@ static void sock_shutdown(struct nbd_device 
>> *nbd)
>>  	struct nbd_config *config = nbd->config;
>>  	int i;
>> 
>> -	if (config->num_connections == 0)
>> +	if (config->num_connections == 0) {
>> +		clear_bit(NBD_BOUND, &config->runtime_flags);
>>  		return;
>> -	if (test_and_set_bit(NBD_DISCONNECTED, &config->runtime_flags))
>> +	}
>> +	if (test_and_set_bit(NBD_DISCONNECTED, &config->runtime_flags)) {
>> +		clear_bit(NBD_BOUND, &config->runtime_flags);
>>  		return;
>> +	}
>> 
>>  	for (i = 0; i < config->num_connections; i++) {
>>  		struct nbd_sock *nsock = config->socks[i];
>> @@ -944,7 +948,7 @@ static int nbd_reconnect_socket(struct nbd_device
>> *nbd, unsigned long arg)
>>  		sockfd_put(old);
>> 
>>  		clear_bit(NBD_DISCONNECTED, &config->runtime_flags);
>> -
>> +		clear_bit(NBD_BOUND, &config->runtime_flags);
>>  		/* We take the tx_mutex in an error path in the recv_work, so we
>>  		 * need to queue_work outside of the tx_mutex.
>>  		 */
>> @@ -1020,6 +1024,7 @@ static int nbd_disconnect(struct nbd_device 
>> *nbd)
>>  	dev_info(disk_to_dev(nbd->disk), "NBD_DISCONNECT\n");
>>  	set_bit(NBD_DISCONNECT_REQUESTED, &config->runtime_flags);
>>  	send_disconnects(nbd);
>> +	clear_bit(NBD_BOUND, &config->runtime_flags);
>>  	return 0;
>>  }