IB/srp: Handle partial connection success correctly

commit c257ea6f upstream.

Avoid that the following kernel warning is reported if the SRP
target system accepts fewer channels per connection than what
was requested by the initiator system:

WARNING: at drivers/infiniband/ulp/srp/ib_srp.c:617 srp_destroy_qp+0xb1/0x120 [ib_srp]()
Call Trace:
[<ffffffff8105d67f>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8105d6da>] warn_slowpath_null+0x1a/0x20
[<ffffffffa05419e1>] srp_destroy_qp+0xb1/0x120 [ib_srp]
[<ffffffffa05445fb>] srp_create_ch_ib+0x19b/0x420 [ib_srp]
[<ffffffffa0545257>] srp_create_target+0x7d7/0xa94 [ib_srp]
[<ffffffff8138dac0>] dev_attr_store+0x20/0x30
[<ffffffff812079ef>] sysfs_write_file+0xef/0x170
[<ffffffff81191fc4>] vfs_write+0xb4/0x130
[<ffffffff8119276f>] sys_write+0x5f/0xa0
[<ffffffff815a0a59>] system_call_fastpath+0x16/0x1b
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Sebastian Parschauer <sebastian.riemer@profitbricks.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/infiniband/ulp/srp/ib_srp.c

@@ -3266,7 +3266,7 @@ static ssize_t srp_create_target(struct device *dev,
 					srp_free_ch_ib(target, ch);
 					srp_free_req_data(target, ch);
 					target->ch_count = ch - target->ch;
-					break;
+					goto connected;
 				}
 			}
 
@@ -3276,6 +3276,7 @@ static ssize_t srp_create_target(struct device *dev,
 		node_idx++;
 	}
 
+connected:
 	target->scsi_host->nr_hw_queues = target->ch_count;
 
 	ret = srp_add_target(host, target);