Commit Graph

22 Commits

Author SHA1 Message Date
Uma Krishnan
d91dd3a7d1 scsi: cxlflash: Update synchronous interrupt status bits
The SISLite specification has been updated to define new synchronous interrupt
status bits. These bits are set by the AFU when a given PASID or EA is bad and
a synchronous interrupt is triggered.

The SISLite header file is updated to support these new bits. Note that there
are also some formatting updates to some of the existing bits to allow all of
the definitions to line up uniformly.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-04-18 19:32:50 -04:00
Uma Krishnan
23239eeccb scsi: cxlflash: Setup LISNs for user contexts
The SISLite specification has been updated for OCXL to support communicating
data to generate AFU interrupts to the AFU. This includes a new capability bit
that is advertised for OCXL AFUs and new registers to hold the object handle
and translation PASID of each interrupt. For Power, the object handle is the
mapped trigger page. Note that because these mappings are kernel only, the
PASID of a kernel context must be used to satisfy the translation.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-04-18 19:32:50 -04:00
Matthew R. Ochs
465891fe92 scsi: cxlflash: Avoid clobbering context control register value
The SISLite specification originally defined the context control register with
a single field of bits to represent the LISN and also stipulated that the
register reset value be 0. The cxlflash driver took advantage of this when
programming the LISN for the master contexts via an unconditional write - no
other bits were preserved.

When unmap support was added, SISLite was updated to define bit 0 of the
context control register as a way for the AFU to notify the context owner that
unmap operations were supported. Thus the assumptions under which the register
is setup changed and the existing unconditional write is clobbering the unmap
state for master contexts. This is presently not an issue due to the order in
which the context control register is programmed in relation to the unmap bit
being queried but should be addressed to avoid a future regression in the
event this code is moved elsewhere.

To remedy this issue, preserve the bits when programming the LISN field in the
context control register. Since the LISN will now be programmed using a read
value, assert that the initial state of the LISN field is as described in
SISLite (0).

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-04-18 19:32:47 -04:00
Matthew R. Ochs
285e6670d0 scsi: cxlflash: Use derived maximum write same length
The existing write same routine within the cxlflash driver uses a
statically defined value for the maximum write same transfer length.
While this is close to the value reflected by the original device that
was supported by cxlflash, newer devices are capable of much larger
lengths. Supporting what the device is capable of offers substantial
performance improvement as the scrub routine within cxlflash operates on
'chunk size' units (256MB with a 4K sector size).

Instead of a #define, use the write same maximum length that is stored
in the block layer in units of 512 byte sectors. This value is initially
determined from the block limits VPD page during device discovery and
can also be manipulated from sysfs. As a general cleanup, designate the
timeout used when executing the write same command as constant.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-10-31 12:28:02 -04:00
Matthew R. Ochs
3223c01aa1 scsi: cxlflash: Support WS16 unmap
The cxlflash driver supports performing a write-same16 to scrub virtual
luns when they are released by a user. To date, AFUs for adapters that
are supported by cxlflash do not have the capability to unmap as part of
the WS operation. This can lead to fragmented flash devices which results
in performance degradation.

Future AFUs can optionally support unmap write-same commands and reflects
this support via the context control register. This provides userspace
applications with direct visibility such that they need not depend on a
host API.

Detect unmap support during cxlflash initialization by reading the context
control register associated with the primary hardware queue. Update the
existing write_same16() routine to set the unmap bit in the CDB when unmap
is supported by the host.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-26 15:01:13 -04:00
Matthew R. Ochs
bc88ac47d5 scsi: cxlflash: Support AFU debug
Adopt the SISLite AFU debug capability to allow future CXL Flash
adapters the ability to better debug AFU issues. Update the SISLite
header with the changes necessary to support AFU debug operations
and create a host ioctl interface for user debug software. Also
update the cxlflash documentation to describe this new host ioctl.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-26 15:01:12 -04:00
Matthew R. Ochs
9cf43a3604 scsi: cxlflash: Support LUN provisioning
Adopt the SISLite AFU LUN provisioning capability to allow future CXL
Flash adapters the ability to better manage storage. Update the SISLite
header with the changes necessary to support LUN provision operations
and create a host ioctl interface for user LUN management software. Also
update the cxlflash documentation to describe this new host ioctl.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-26 15:01:12 -04:00
Matthew R. Ochs
cf24302790 scsi: cxlflash: Separate AFU internal command handling from AFU sync specifics
To date the only supported internal AFU command is AFU sync. The logic
to send an internal AFU command is embedded in the specific AFU sync
handler and would need to be duplicated for new internal AFU commands.

In order to support new internal AFU commands, separate code that is
common for AFU internal commands into a generic transmission routine
and support passing back command status through an IOASA structure.
The first user of this new routine is the existing AFU sync command.
As a cleanup, use a descriptive name for the AFU sync command instead
of a magic number.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-26 15:01:11 -04:00
Matthew R. Ochs
fcc87e74a9 scsi: cxlflash: Fix warnings/errors
As a general cleanup, address all reasonable checkpatch warnings and
errors. These include enforcement of comment styles and including named
identifiers in function prototypes.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13 22:55:41 -04:00
Matthew R. Ochs
1cd7fabc82 scsi: cxlflash: Support up to 4 ports
Update the driver to allow for future cards with 4 ports.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13 22:55:41 -04:00
Matthew R. Ochs
5651807232 scsi: cxlflash: SISlite updates to support 4 ports
Update the SISlite header to support 4 ports as outlined in the SISlite
specification. Address fallout from structure renames and refreshed
organization throughout the driver. Determine the number of ports supported by
a card from the global port selection mask register reset value.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13 22:55:41 -04:00
Matthew R. Ochs
8fa4f1770d scsi: cxlflash: Remove port configuration assumptions
At present, the cxlflash driver only supports hardware with two FC ports. The
code was initially designed with this assumption and is dependent on having
two FC ports - adding more ports will break logic within the driver.

To mitigate this issue, remove the existing port assumptions and transition
the code to support more than two ports. As a side effect, clarify the
interpretation of the DK_CXLFLASH_ALL_PORTS_ACTIVE flag.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13 22:55:41 -04:00
Matthew R. Ochs
78ae028e82 scsi: cxlflash: Support dynamic number of FC ports
Transition from a static number of FC ports to a value that is derived during
probe. For now, a static value is used but this will later be based on the
type of card being configured.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13 22:55:41 -04:00
Matthew R. Ochs
696d0b0c71 scsi: cxlflash: Support SQ Command Mode
The SISLite specification outlines a new queuing model to improve
over the MMIO-based IOARRIN model that exists today. This new model
uses a submission queue that exists in host memory and is shared with
the device. Each entry in the queue is an IOARCB that describes a
transfer request. When requests are submitted, IOARCBs ('current'
position tracked in host software) are populated and the submission
queue tail pointer is then updated via MMIO to make the device aware
of the requests.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-11 22:38:15 -05:00
Matthew R. Ochs
fe7f96982a scsi: cxlflash: Migrate scsi command pointer to AFU command
Currently, when sending a SCSI command, the pointer is stored in a
reserved field of the AFU command descriptor for retrieval once the
SCSI command has completed. In order to support new descriptor formats
that make use of the reserved field, the pointer is migrated to outside
the descriptor where it can still be found during completion processing.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-30 19:53:02 -05:00
Uma Krishnan
704c4b0ddc cxlflash: Shutdown notify support for CXL Flash cards
Some CXL Flash cards need notification of device shutdown in order to
flush pending I/Os.

A PCI notification hook for shutdown has been added where the driver
notifies the card and returns. When the device is removed in the PCI
remove path, notification code will wait for shutdown processing to
complete.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-07-12 23:16:31 -04:00
Matthew R. Ochs
f15fbf8d4e cxlflash: Correct spelling, grammar, and alignment mistakes
There are several spelling and grammar mistakes throughout the
driver. Additionally there are a handful of places where there
are extra lines and unnecessary variables/statements. These are
a nuisance and pollute the driver.

Fix spelling and grammar issues. Update some comments for clarity and
consistency. Remove extra lines and a few unneeded variables/statements.

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: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-10-30 17:18:28 +09:00
Matthew R. Ochs
e5ce067b7b cxlflash: Fix AFU version access/storage and add check
The AFU version is stored as a non-terminated string of bytes within
a 64-bit little-endian register. Presently the value is read directly
(no MMIO accessor) and is stored in a buffer that is not big enough
to contain a NULL terminator. Additionally the version obtained is not
evaluated against a known value to prevent usage with unsupported AFUs.
All of these deficiencies can lead to a variety of problems.

To remedy, use the correct MMIO accessor to read the version value into
a null-terminated buffer and add a check to prevent an incompatible AFU
from being used with this driver.

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 17:14:41 +09:00
Matthew R. Ochs
2cb79266d6 cxlflash: Virtual LUN support
Add support for physical LUN segmentation (virtual LUNs) to device
driver supporting the IBM CXL Flash adapter. This patch allows user
space applications to virtually segment a physical LUN into N virtual
LUNs, taking advantage of the translation features provided by this
adapter.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-26 18:05:39 -07:00
Matthew R. Ochs
65be2c79ac cxlflash: Superpipe support
Add superpipe supporting infrastructure to device driver for the IBM CXL
Flash adapter. This patch allows userspace applications to take advantage
of the accelerated I/O features that this adapter provides and bypass the
traditional filesystem stack.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-26 18:04:37 -07:00
Matthew R. Ochs
5cdac81a87 cxlflash: Base error recovery support
Introduce support for enhanced I/O error handling.

A device state is added to track 3 possible states of the device:

Normal - the device is operating normally and is fully operational

Limbo - the device is in a reset/recovery scenario and its operational
        status is paused

Failed/terminating - the device has either failed to be reset/recovered
                     or is being terminated (removed); it is no longer
                     operational

All operations are allowed when the device is operating normally. When the
device transitions to limbo state, I/O must be paused. To help accomplish
this, a wait queue is introduced where existing and new threads can wait
until the device is no longer in limbo. When coming out of limbo, threads
need to check the state and error out gracefully when encountering the
failed state. When the device transitions to the failed/terminating state,
normal operations are no longer allowed. Only specially designated
operations related to graceful cleanup are permitted.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-08-26 18:03:47 -07:00
Matthew R. Ochs
c21e0bbfc4 cxlflash: Base support for IBM CXL Flash Adapter
SCSI device driver to support filesystem access on the IBM CXL Flash adapter.

Supported-by: Stephen Bates <stephen.bates@pmcs.com>
Reviewed-by: Michael Neuling <mikey@neuling.org>
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>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-07-30 21:02:01 -07:00