Removes unnecessary usage of BUG_ON macro, excluding core directory.
In some cases macro is unnecesary, check is done in caller function.
In other cases macro is replaced by if construction with
appropriate warning.
Signed-off-by: NMaciej Patelczyk <maciej.patelczyk@intel.com>
[changed some survivable bug conditions to WARN_ONCE]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Clean warnings and errors reported by sparse tool.

request.c:430:50: warning: mixing different enum types
remote_device.c:534:39: warning: symbol 'flags' shadows an earlier one
task.c:495:44: warning: mixing different enum types
scic_sds_controller.c:2155:24: warning: mixing different enum types
scic_sds_controller.c:2272:36: warning: mixing different enum types
scic_sds_controller.c:2911:38: warning: incorrect type in initializer (different address spaces)
scic_sds_controller.c:2913:25: warning: incorrect type in argument 2 (different address spaces)
scic_sds_request.c:875:34: warning: cast removes address space of expression
scic_sds_request.c:876:123: warning: incorrect type in argument 2 (different address spaces)
scic_sds_port.c:585:51: warning: incorrect type in assignment (different address spaces)
scic_sds_port.c:712:9: warning: incorrect type in argument 2 (different address spaces)
scic_sds_port.c:1770:25: warning: incorrect type in argument 2 (different address spaces)
Signed-off-by: NBartosz Barcinski <Bartosz.Barcinski@intel.com>
Signed-off-by: NMaciej Patelczyk <maciej.patelczyk@intel.com>
[fixed up some false positives and misconversions]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

A domain_device can always reference back to ->lldd_ha unlike local lldd
structures.  Fix up cases where the driver uses local objects to look up the
isci_host.  This also changes the calling conventions of some routines to
expect a valid isci_host parameter rather than re-lookup the pointer on entry.

Incidentally cleans up some macros that are longer to type than the open-coded
equivalent:
  isci_host_from_sas_ha
  isci_dev_from_domain_dev
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Require a valid isci_host in support of the general cleanup to not
re-lookup the host via potentially fragile methods when more robust
methods are available.  Also cleans up some more casting that should be
using container_of() to up-cast a base structure in a more type-safe
manner.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Make sure all pending I/O including any in the libsas error handler
process is cleaned-up.
Signed-off-by: NJeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The remote_device_lock is currently used to protect a controller global
resource (RNCs), but the remote_device_lock is per-port.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Until we synchronize against device removal this limits the damage of
use after free bugs to the driver's own objects.  Unless we implement
reference counting we need to ensure at least a subset of a remote
device is valid at all times.  We follow the lead of other libsas
drivers that also preallocate devices.

This also enforces maximum remote device accounting at the lldd layer,
but the core may still run out of RNC's before we hit this limit.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Replace the device completion infrastructure with the controller wide
event queue.  There was a potential for the stop and ready notifications
to corrupt each other, now that cannot happen.

The stop pending flag cannot be used until devices are statically
allocated.  We temporarily need to maintain a completion to handle
waiting for an object that has disappeared, but we can at least stop
scribbling on freed memory.

A future change will also get rid of the "stopping" state as it should
not be exposed to the rest of the driver.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The midlayer is already throttling i/o in the places where host_quiesce
was trying to prevent further i/o to the device.  It's also problematic
in that it holds a lock over GFP_KERNEL allocations.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

It belies the fact that isci_remote_device and scic_sds_remote_device
are one in same object with the same lifetime rules.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Moving some of the chattiness of warning messages to debug so only the Linux
system messages are shown.
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Some of the chain walks to get back to our dev are invalid.

isci_remote_device_change_state: delete rather than adding conditional deref
chain walking
isci_request_change_state: fix, it was being called too early
isci_request_ssp_io_request_get_lun: fix compile breakage hidden by ifdef DEBUG
Signed-off-by: NMaciej Trela <maciej.trela@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The lldd actively disallows requests in the "starting" state.  Retrying
or holding off commands in this state is sub-optimal:
1/ it adds another state check to the fast path
2/ retrying can cause libsas to give up

However, isci's ->lldd_dev_found() routine already waits for controller
start to complete before allowing further progress.  Checking the
"starting" state in isci_task_execute_task and the isr is redundant and
misleading.  Clean this up and introduce a controller-wide event queue
to start reeling in "completion" proliferation in the driver.

The "stopping" state cleanups are in a similar vein, rely on the the isr
and other paths being precluded from occurring rather than implementing
state checking logic.
Reported-by: NChristoph Hellwig <hch@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Support for the up to 2x4-port 6Gb/s SAS controllers embedded in the
chipset.

This is a snapshot of the first publicly available version of the driver,
commit 4c1db2d0 in the 'historical' branch.

   git://git.kernel.org/pub/scm/linux/kernel/git/djbw/isci.git historical
Signed-off-by: NMaciej Trela <maciej.trela@intel.com>
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>