Per-Target Instance Data

An HBA driver must allocate a scsi_hba_tran(9S) structure during attach(9E) and initialize the vectors in this transport structure to point to the required HBA driver entry points. This scsi_hba_tran(9S) structure is then passed into scsi_hba_attach_setup(9F).

The scsi_hba_tran(9S) structure contains a tran_hba_private field, which can be used to refer to the HBA driver's per-instance state.

Each scsi_address(9S) structure contains a pointer to the scsi_hba_tran(9S) structure and also provides the target (a_target) and logical unit (a_lun) addresses for the particular target device. Because every HBA driver entry point is passed a pointer to the scsi_address(9S) structure, either directly or indirectly through the scsi_device(9S) structure, the HBA driver can reference its own state and can identify the target device being addressed.

The following figure illustrates the HBA data structures for transport operations.

Figure 15–3 HBA Transport Structures