• Christoph Hellwig's avatar
    [SCSI] remove target parent limitiation · e02f3f59
    Christoph Hellwig authored
    
    
    When James Smart fixed the issue of the userspace scan atributes
    crashing the system with the FC transport class he added a patch to
    let the transport class check if the parent is valid for a given
    transport class.
    
    When adding support for the integrated raid of fusion sas devices
    we ran into a problem with that, as it didn't allow adding virtual
    raid volumes without the transport class knowing about it.
    
    So this patch adds a user_scan attribute instead, that takes over from
    scsi_scan_host_selected if the transport class sets it and thus lets
    the transport class control the user-initiated scanning.  As this
    plugs the hole about user-initiated scanning the target_parent hook
    goes away and we rely on callers of the scanning routines to do
    something sensible.
    
    For SAS this meant I had to switch from a spinlock to a mutex to
    synchronize the topology linked lists, in FC they were completely
    unsynchronized which seems wrong.
    Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
    Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
    e02f3f59