• Martin K. Petersen's avatar
    [SCSI] Command protection operation · db007fc5
    Martin K. Petersen authored
    Controllers that support DMA of protection information must be told
    explicitly how to handle the I/O.  The controller has no knowledge of
    the protection capabilities of the target device so this information
    must be passed in the scsi_cmnd.
    
     - The protection operation tells the HBA whether to generate, strip or
       verify protection information.
    
     - The protection type tells the HBA which layout the target is
       formatted with.  This is necessary because the controller must be
       able to correctly interpret the included protection information in
       order to verify it.
    
     - When a scsi_cmnd is reused for error handling the protection
       operation must be cleared and saved while error handling is in
       progress.
    
     - prot_op and prot_type are placed in an existing hole in scsi_cmnd
       and don't cause the structure to grow.
    Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
    Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
    db007fc5
scsi_cmnd.h 7.68 KB