[PATCH] sbp2: fix deadlocks and delays on device removal/rmmod
Fixes for deadlocks of the ieee1394 and scsi subsystems and long delays in
futile error recovery attempts when SBP-2 devices are removed or drivers are
unloaded.
- Complete commands quickly with DID_NO_CONNECT if the 1394 node is gone or if
the 1394 low-level driver was unloaded.
- Skip unnecessary work in the eh_abort_handler and eh_device_reset_handler if
the node or 1394 low-level driver is gone.
- Let scsi's high-level shut down gracefully when sbp2 is being unloaded or
detached from the 1394 unit. A call to scsi_remove_device is added for this
purpose, which requires us to store a scsi_device pointer.
- scsi_device pointer is obtained from slave_alloc hook and cleared by
slave_destroy. This avoids usage of the pointer after the scsi device was
deleted e.g. by the user via scsi_mod's sysfs interface.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Jody McIntyre <scjody@steamballoon.com> Cc: Ben Collins <bcollins@debian.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>