linux/drivers/scsi/cxlflash
Matthew R. Ochs 0a27ae5147 cxlflash: Fix to avoid CXL services during EEH
During an EEH freeze event, certain CXL services should not be
called until after the hardware reset has taken place. Doing so
can result in unnecessary failures and possibly cause other ill
effects by triggering hardware accesses. This translates to a
requirement to quiesce all threads that may potentially use CXL
runtime service during this window. In particular, multiple ioctls
make use of the CXL services when acting on contexts on behalf of
the user. Thus, it is essential to 'drain' running ioctls _before_
proceeding with handling the EEH freeze event.

Create the ability to drain ioctls by wrapping the ioctl handler
call in a read semaphore and then implementing a small routine that
obtains the write semaphore, effectively creating a wait point for
all currently executing ioctls.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-10-30 17:02:40 +09:00
..
common.h cxlflash: Fix to avoid CXL services during EEH 2015-10-30 17:02:40 +09:00
Kconfig
lunmgt.c cxlflash: Fix to avoid invalid port_sel value 2015-10-30 16:57:21 +09:00
main.c cxlflash: Fix to avoid CXL services during EEH 2015-10-30 17:02:40 +09:00
main.h
Makefile cxlflash: Virtual LUN support 2015-08-26 18:05:39 -07:00
sislite.h cxlflash: Virtual LUN support 2015-08-26 18:05:39 -07:00
superpipe.c cxlflash: Fix to avoid CXL services during EEH 2015-10-30 17:02:40 +09:00
superpipe.h cxlflash: Fix context encode mask width 2015-10-30 17:02:06 +09:00
vlun.c cxlflash: Fix data corruption when vLUN used over multiple cards 2015-10-30 17:01:07 +09:00
vlun.h cxlflash: Virtual LUN support 2015-08-26 18:05:39 -07:00