cciss: separate cmd_alloc() and cmd_special_alloc()
cmd_alloc() took a parameter which caused it to either allocate
from a pre-allocated pool, or allocate using pci_alloc_consistent.
This parameter is always known at compile time, so this would
be better handled by breaking the function into two functions
and differentiating the cases by function names. Same goes
for cmd_free().
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
cciss: use consistent variable names
"h", for the hba structure and "c" for the command structures.
and get rid of trivial CCISS_LOCK macro.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
cciss: forbid hard reset of 640x boards
The 6402/6404 are two PCI devices -- two Smart Array controllers
-- that fit into one slot. It is possible to reset them independently,
however, they share a battery backed cache module. One of the pair
controls the cache and the 2nd one access the cache through the first
one. If you reset the one controlling the cache, the other one will
not be a happy camper. So we just forbid resetting this conjoined
mess.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
cciss: sanitize max commands
Some controllers might try to tell us they support 0 commands
in performant mode. This is a lie told by buggy firmware.
We have to be wary of this lest we try to allocate a negative
number of command blocks, which will be treated as unsigned,
and get an out of memory condition.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
cciss: Fix hard reset code.
Smart Array controllers newer than the P600 do not honor the
PCI power state method of resetting the controllers. Instead,
in these cases we can get them to reset via the "doorbell" register.
This escaped notice until we began using "performant" mode because
the fact that the controllers did not reset did not normally
impede subsequent operation, and so things generally appeared to
"work". Once the performant mode code was added, if the controller
does not reset, it remains in performant mode. The code immediately
after the reset presumes the controller is in "simple" mode
(which previously, it had remained in simple mode the whole time).
If the controller remains in performant mode any code which presumes
it is in simple mode will not work. So the reset needs to be fixed.
Unfortunately there are some controllers which cannot be reset by
either method. (eg. p800). We detect these cases by noticing that
the controller seems to remain in performant mode even after a
reset has been attempted. In those cases we ignore the controller,
as any commands outstanding on it will result in stale completions.
To sum up, we try to do a better job of resetting the controller if
"reset_devices" is set, and if it doesn't work, we ignore that
controller.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Rationale for this is that I will also need to use this code
in fixing kdump host reset code prior to having the hba structure.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
cciss: save pdev pointer in per hba structure early to avoid passing it around so much.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
cciss: Set the performant mode bit in the scsi half of the driver
In a couple of places, the performant mode bit wasn't being set in
the scsi half of the driver, causing commands to seem to hang. Use
enqueue_cmd_and_start_io() where appropriate. This fixes a bug that
echo engage scsi > /proc/driver/cciss/cciss0
would hang.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>