Access control and security for synchronous input/output links
Aspects include providing automatic access control and security for a synchronous input/output (I/O) link. Providing automatic access control and security includes initializing devices of a storage environment over a first link to verify that the devices are available within the storage environment; building a table of identifiers, where each of the identifiers is assigned one of the devices that have been initialized; and verifying a first device attempting to perform synchronous I/O commands across the synchronization I/O link by confirming that an identifier assigned to the first device is within the table of identifiers.
1. A computer program product, the computer program product comprising a computer readable storage medium having program instructions for providing automatic access control and security for a synchronous input/output (I/O) link embodied therewith, the program instructions executable by a processor to cause the processor to perform:
initializing devices of a storage environment over a first link to verify that the devices are available within the storage environment;
modifying a link token of a mailbox command block in response the initializing devices, wherein the link token that is negotiated each time the synchronous I/O link is initialized;
building a table of identifiers, each of the identifiers is assigned one of the devices that have been initialized;
verifying a first device attempting to perform synchronous I/O commands across the synchronization I/O link by confirming that an identifier assigned to the first device is within the table of identifiers;
passing the link token between a logical partition and when performing synchronous I/O commands; and
placing, by host firmware, information comprising a channel image and worldwide node name target information into a mailbox based on the synchronous I/O commands.
2. The computer program product of claim 1 , wherein the program instructions are further executable by the processor to cause:
checking a target worldwide node name to determine that no errors have occurred on the synchronous input/output (I/O) link with respect to the synchronous I/O commands.
3. The computer program product of claim 1 , wherein the information includes a target storage control unit image, a unit address, a worldwide unique node name, a logical partition identification, and a function handle.
4. The computer program product of claim 1 , wherein the identifiers are path group identifiers.
5. A system, comprising a processor and a memory storing program instructions for providing automatic access control and security for a synchronous input/output (I/O) link thereon, the program instructions executable by a processor to cause the system to perform:
initializing devices of a storage environment over a first link to verify that the devices are available within the storage environment;
modifying a link token of a mailbox command block in response the initializing devices, wherein the link token that is negotiated each time the synchronous I/O link is initialized;
building a table of identifiers, each of the identifiers is assigned one of the devices that have been initialized;
verifying a first device attempting to perform synchronous I/O commands across the synchronization I/O link by confirming that an identifier assigned to the first device is within the table of identifiers;
passing the link token between a logical partition and when performing synchronous I/O commands; and
placing, by host firmware, information comprising a channel image and worldwide node name target information into a mailbox based on the synchronous I/O commands.
6. The system of claim 5 , the program instructions are further executable by the processor to cause the system to perform:
checking a target worldwide node name to determine that no errors have occurred on the synchronous input/output (I/O) link with respect to the synchronous I/O commands.
7. The system of claim 5 , wherein the information includes a target storage control unit image, a unit address, a worldwide unique node name, a logical partition identification, and a function handle.
8. The system of claim 5 , wherein the identifiers are path group identifiers.