nvmeof: treat "connecting" state as valid in path detection

When checking if a path to a gateway already exists,
treat both "live" and "connecting" states as
valid connections that should not be re-attempted.

The "connecting" state indicates the NVMe kernel
is actively trying to establish or re-establish
a connection, which occurs in scenarios like:

- Initial connection establishment
- Gateway temporarily unavailable and kernel retrying
- Subsystem deleted and recreated on the gateway

The kernel's ctrl_loss_tmo mechanism will continue
retry attempts for up to 30 minutes
( by -l param in nvme connect command).
Attempting nvme connect while a path is in
"connecting" state results in "already connected"
errors and can cause volume attachment failures
during create/delete cycles.

By treating "connecting" as a valid state,
we allow the kernel's retry logic to handle
reconnection automatically without interference.

Signed-off-by: gadi-didi <gadi.didi@ibm.com>

Author: gadididi

internal/nvmeof/nvmeof_initiator.go

@@ -261,10 +261,25 @@ func (nhc nvmeHostConnections) hasLivePathToGateway(subsystemNQN, hostNQN,
 				continue
 			}
 
+			// loop through paths to find matching path
 			for _, path := range subsys.Paths {
+				// Check if the path matches the gateway IP and port
+				// and is in a usable state:
+				// - "live": connection is active and working
+				// - "connecting": kernel is actively trying to (re)connect
+				//
+				// The "connecting" state occurs when:
+				// 1. Initial connection is being established
+				// 2. Connection lost and kernel is retrying (ctrl_loss_tmo in effect)
+				// 3. Subsystem was deleted/recreated on the gateway
+				//
+				// In all cases, the kernel's retry mechanism handles reconnection
+				// for up to ctrl_loss_tmo seconds, so we should not attempt another
+				// connection which would fail with "already connected" error.
 				if path.Address.Traddr == gatewayIP &&
 					path.Address.Trsvcid == gatewayPort &&
-					path.State == "live" {
+					(path.State == "live" ||
+						path.State == "connecting") {
 					return true
 				}
 			}