Commit Graph

100 Commits

Author SHA1 Message Date
Uma Krishnan
0df5bef739 scsi: cxlflash: Cancel scheduled workers before stopping AFU
When processing an AFU asynchronous interrupt, if the action results in an
operation that requires off level processing (a link reset for example),
the worker thread is scheduled. In the meantime a reset event (i.e.: EEH)
could unmap the AFU to recover. This results in an Oops when the worker
thread tries to access the AFU mapping.

[c000000f17e03b90] d000000007cd5978 cxlflash_worker_thread+0x268/0x550
[c000000f17e03c40] c00000000011883c process_one_work+0x1dc/0x680
[c000000f17e03ce0] c000000000118e80 worker_thread+0x1a0/0x520
[c000000f17e03d80] c000000000126174 kthread+0xf4/0x100
[c000000f17e03e30] c00000000000a47c ret_from_kernel_thread+0x5c/0xe0

In an effort to avoid this, a mapcount was introduced in
commit b45cdbaf9f ("cxlflash: Resolve oops in wait_port_offline")
but due to the race condition described above, this solution is incomplete.

In order to fully resolve this problem and to simplify things, this commit
removes the mapcount solution. Instead, the scheduled worker thread is
cancelled after interrupts have been disabled and prior to the mapping
being freed.

Fixes: b45cdbaf9f ("cxlflash: Resolve oops in wait_port_offline")
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>
2017-01-11 22:38:15 -05:00
Matthew R. Ochs
fb67d44dfb scsi: cxlflash: Cleanup prints
The usage of prints within the cxlflash driver is inconsistent. This
hinders debug and makes the driver source and log output appear sloppy.

The following cleanups help unify the prints within cxlflash:
 - move all prints to dev-* where possible
 - transition all hex prints to lowercase
 - standardize variable prints in debug output
 - derive pointers in a consistent manner
 - change int to bool where appropriate
 - remove superfluous data from prints and print statements that do not
   make sense

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-11 22:38:15 -05:00
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
9c7d1ee5f1 scsi: cxlflash: Refactor context reset to share reset logic
As staging for supporting hardware with different context reset
registers but a similar reset procedure, refactor the existing context
reset routine to move the reset logic to a common routine. This will
allow hardware with a different reset register to leverage existing
code.

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 22:38:14 -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
Matthew R. Ochs
48b4be36ed scsi: cxlflash: Migrate IOARRIN specific routines to function pointers
As staging for supporting hardware with a different queuing mechanism,
move the send_cmd() and context_reset() routines to function pointers
that are configured when the AFU is initialized. In addition, rename
the existing routines to better reflect the queue model they support.

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
Matthew R. Ochs
9d89326c66 scsi: cxlflash: Cleanup queuecommand()
The queuecommand routine is disorganized where it populates the
private command and also contains some logic/statements that are
not needed given that cxlflash devices do not (and likely never
will) support scatter-gather.

Restructure the code to remove the unnecessary logic and create an
organized flow:

	handle state -> DMA map -> populate command -> send command

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
Matthew R. Ochs
d4ace35166 scsi: cxlflash: Cleanup send_tmf()
The send_tmf() routine includes some copy/paste cruft that can be
removed as well as the setting of an AFU command-specific while
holding the tmf_slock. While not a bug, it is out of place and
should be shifted down alongside the other command initialization
statements for clarity.

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
Matthew R. Ochs
9ba848acbf scsi: cxlflash: Remove AFU command lock
The original design of the cxlflash driver required AFU commands
to convey state information across multiple threads. The IOASA
"host use" byte was used to track if a command was done, errored,
or timed out. A per-command spin lock was used to serialize access
to this byte. As this is no longer required with the introduction
of completions and various refactoring over time, the spin lock,
state tracking, and associated code can be removed. To support the
simplification, the wait_resp() routine is refactored to return a
success or failure. Additionally, as the simplification to the
AFU internal command routine, explicit assignments of AFU command
fields to zero are removed as the memory is zeroed upon allocation.

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
Matthew R. Ochs
de01283baa scsi: cxlflash: Wait for active AFU commands to timeout upon tear down
With the removal of the static private command pool, the ability to
'complete' outstanding commands was lost. While not an issue for the
commands originating outside the driver, internal AFU commands are
synchronous and therefore have a timeout associated with them. To
avoid a stale memory access, the tear down sequence needs to ensure
that there are not any active commands before proceeding. As these
internal AFU commands are rare events, the simplest way to accomplish
this is detecting the activity and waiting for it to timeout.

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
Matthew R. Ochs
25bced2b61 scsi: cxlflash: Remove private command pool
Clean up and remove the remaining private command pool infrastructure
that is no longer required.

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
Matthew R. Ochs
5fbb96c8f1 scsi: cxlflash: Use cmd_size for private commands
Instead of using a private pool of AFU commands, use cmd_size to prime
the private pool of SCSI commands such that they are allocated with a
size large enough to contain an aligned AFU command. Use scsi_cmd_priv()
to derive the aligned/zeroed private command on queuecommand and TMF
paths. Remove cmd_checkout() as it is no longer required. The remaining
AFU private command infrastructure will be removed in a cleanup commit.

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
Matthew R. Ochs
350bb478f5 scsi: cxlflash: Allocate memory instead of using command pool for AFU sync
As staging for the removal of the AFU command pool, remove the reliance
upon the pool for the internal AFU sync command. Instead of obtaining an
AFU command from the pool, dynamically allocate memory with the appropriate
alignment requirements. Since the AFU sync service is only executed from
the process environment, blocking is acceptable.

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 19:53:01 -05:00
Matthew R. Ochs
e7ab2d401d scsi: cxlflash: Remove unused buffer from AFU command
The cxlflash driver originally required a per-command 4K buffer that
hosted data passed to the AFU. When the routines that initiate AFU
and internal SCSI commands were refactored to use scsi_execute(), the
need for this buffer became obsolete. As it is no longer necessary,
the buffer is removed.

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 19:53:01 -05:00
Uma Krishnan
11f7b1844a scsi: cxlflash: Avoid command room violation
During test, a command room violation interrupt is occasionally seen
for the master context when the CXL flash devices are stressed.

After studying the code, there could be gaps in the way command room
value is being cached in cxlflash. When the cached command room is zero
the thread attempting to send becomes burdened with updating the cached
value with the actual value from the AFU. Today, this is handled with an
atomic set operation of the raw value read. Following the atomic update,
the thread proceeds to send.

This behavior is incorrect on two counts:

   - The update fails to take into account the current thread and its
     consumption of one of the hardware commands.

   - The update does not take into account other threads also atomically
     updating. Per design, a worker thread updates the cached value when a
     send thread times out. By not protecting the update with a lock, the
     cached value can be incorrectly clobbered.

To correct these issues, the update of the cached command room has been
simplified and also protected using a spin lock which is held until the
MMIO is complete. This ensures the command room is properly consumed by
the same thread. Update of cached value also takes into account the
current thread consuming a hardware command.

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>
2016-11-30 11:34:01 -05:00
Uma Krishnan
3d2f617d44 scsi: cxlflash: Improve context_reset() logic
Currently, the context reset routine waits for command room to
be available before sending the reset request. Per review of the
SISLite specification and clarifications from the CXL Flash AFU
designers, this wait is unnecessary. The reset request can be
sent anytime regardless of command room, so long as only a single
reset request is active at any one point in time.

This commit simplifies the reset routine by removing the wait for
command room. Additionally it adds a debug trace to help pinpoint
hardware errors when a context reset does not complete.

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>
2016-11-30 11:34:01 -05:00
Uma Krishnan
8a2605430a scsi: cxlflash: Fix crash in cxlflash_restore_luntable()
During test, the following crash was observed:

[34538.981505] Faulting instruction address: 0xd000000007c9c870
cpu 0x9: Vector: 300 (Data Access) at [c0000007f1e8f590]
    pc: d000000007c9c870: cxlflash_restore_luntable+0x70/0x1d0 [cxlflash]
    lr: d000000007c9c84c: cxlflash_restore_luntable+0x4c/0x1d0 [cxlflash]
    sp: c0000007f1e8f810
   msr: 9000000100009033
   dar: c00000171d637438
 dsisr: 40000000
  current = 0xc0000007f1e43f90
  paca    = 0xc000000007b25100   softe: 0        irq_happened: 0x01
    pid   = 493, comm = eehd
enter ? for help
[c0000007f1e8f8a0] d000000007c940b0 init_afu+0xd60/0x1200 [cxlflash]
[c0000007f1e8f9a0] d000000007c945a8 cxlflash_pci_slot_reset+0x58/0xe0 [cxlflash]
[c0000007f1e8fa20] d00000000715f790 cxl_pci_slot_reset+0x230/0x340 [cxl]
[c0000007f1e8fae0] c000000000040dd4 eeh_report_reset+0x144/0x180
[c0000007f1e8fb20] c00000000003f708 eeh_pe_dev_traverse+0x98/0x170
[c0000007f1e8fbb0] c000000000041618 eeh_handle_normal_event+0x328/0x410
[c0000007f1e8fc30] c000000000041db8 eeh_handle_event+0x178/0x330
[c0000007f1e8fce0] c000000000042118 eeh_event_handler+0x1a8/0x1b0
[c0000007f1e8fd80] c00000000011420c kthread+0xec/0x100
[c0000007f1e8fe30] c00000000000a47c ret_from_kernel_thread+0x5c/0xe0

When superpipe mode is disabled for a LUN, the references for the
local lun are deleted but the LUN is still identified as being present
in the LUN table. This mismatched state can result in the above crash
when the LUN table is restored during an error recovery operation.

To fix this issue, the local LUN information structure is updated to
reflect the LUN is no longer in the LUN table once all references to
the LUN are gone.

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>
2016-11-30 11:34:00 -05:00
Uma Krishnan
68ab2d76e4 scsi: cxlflash: Set sg_tablesize to 1 instead of SG_NONE
The following Oops is encountered when blk_mq is enabled with the
cxlflash driver:

[ 2960.817172] Oops: Kernel access of bad area, sig: 11 [#5]
[ 2960.817309] NIP  __blk_mq_run_hw_queue+0x278/0x4c0
[ 2960.817313] LR __blk_mq_run_hw_queue+0x2bc/0x4c0
[ 2960.817314] Call Trace:
[ 2960.817320] __blk_mq_run_hw_queue+0x2bc/0x4c0 (unreliable)
[ 2960.817324] blk_mq_run_hw_queue+0xd8/0x100
[ 2960.817329] blk_mq_insert_requests+0x14c/0x1f0
[ 2960.817333] blk_mq_flush_plug_list+0x150/0x190
[ 2960.817338] blk_flush_plug_list+0x11c/0x2b0
[ 2960.817344] blk_finish_plug+0x58/0x80
[ 2960.817348] __do_page_cache_readahead+0x1c0/0x2e0
[ 2960.817352] force_page_cache_readahead+0x68/0xd0
[ 2960.817356] generic_file_read_iter+0x43c/0x6a0
[ 2960.817359] blkdev_read_iter+0x68/0xa0
[ 2960.817361] __vfs_read+0x11c/0x180
[ 2960.817364] vfs_read+0xa4/0x1c0
[ 2960.817366] SyS_read+0x6c/0x110
[ 2960.817369] system_call+0x38/0xb4

The SCSI blk_mq stack assumes that sg_tablesize is always a non-zero
value with scsi_mq_setup_tags() allocating tags using sg_tablesize.
The cxlflash driver currently uses SG_NONE (0) for the sg_tablesize
as the devices it supports are not capable of scatter gather. This
mismatch of values results in the Oops above.

To resolve this issue, sg_tablesize for cxlflash can simply be set
to 1, a value which satisfies the constraints in cxlflash and the
lack of support of SG_NONE in SCSI blk_mq.

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>
2016-11-30 11:34:00 -05:00
Matthew R. Ochs
c4a11827b7 scsi: cxlflash: Fix context reference tracking on detach
Commit 888baf069f ("scsi: cxlflash: Add kref to context") introduced a
kref to the context. In particular, the detach routine was updated to
use the kref services for managing the removal and destruction of a
context.

As part of this change, the tracking mechanism internal to the detach
handler was refactored. This introduced a bug that can cause the
tracking state to be lost. This can lead to a situation where exclusive
access to a context is prematurely [and unknowingly] relinquished for
the executing thread.

To remedy, only update the tracking state when the kref operation
indicates the context was removed.

Fixes: 888baf069f ("scsi: cxlflash: Add kref to context")
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>
2016-09-14 12:47:42 -04:00
Matthew R. Ochs
f80132613d scsi: cxlflash: Refactor WWPN setup
Commit 964497b3bf ("cxlflash: Remove dual port online dependency")
logically removed the ability for the WWPN setup routine afu_set_wwpn()
to return a non-success value. This routine can safely be made a void to
simplify the code as there is no longer a need to report a failure.

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>
2016-09-14 12:47:03 -04:00
Matthew R. Ochs
05dab43230 scsi: cxlflash: Improve EEH recovery time
When an EEH occurs during device initialization, the port timeout logic
can cause excessive delays as MMIO reads will fail. Depending on where
they are experienced, these delays can lead to a prolonged reset,
causing an unnecessary triggering of other timeout logic in the SCSI
stack or user applications.

To expedite recovery, the port timeout logic is updated to decay the
timeout at a much faster rate when in the presence of a likely EEH
frozen event.

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>
2016-09-14 12:46:20 -04:00
Matthew R. Ochs
1d3324c382 scsi: cxlflash: Fix to avoid EEH and host reset collisions
The EEH reset handler is ignorant to the current state of the driver
when processing a frozen event and initiating a device reset. This can
be an issue if an EEH event occurs while a user or stack initiated reset
is executing. More specifically, if an EEH occurs while the SCSI host
reset handler is active, the reset initiated by the EEH thread will
likely collide with the host reset thread. This can leave the device in
an inconsistent state, or worse, cause a system crash.

As a remedy, the EEH handler is updated to evaluate the device state and
take appropriate action (proceed, wait, or disconnect host). The host
reset handler is also updated to handle situations where an EEH occurred
during a host reset. In such situations, the host reset handler will
delay reporting back a success to give the EEH reset an opportunity to
complete.

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>
2016-09-14 12:45:06 -04:00
Uma Krishnan
babf985d1e scsi: cxlflash: Remove the device cleanly in the system shutdown path
Commit 704c4b0ddc ("cxlflash: Shutdown notify support for CXL Flash
cards") was recently introduced to notify the AFU when a system is going
down. Due to the position of the cxlflash driver in the device stack,
cxlflash devices are _always_ removed during a reboot/shutdown. This can
lead to a crash if the cxlflash shutdown hook is invoked _after_ the
shutdown hook for the owning virtual PHB. Furthermore, the current
implementation of shutdown/remove hooks for cxlflash are not tolerant to
being invoked when the device is not enabled. This can also lead to a
crash in situations where the remove hook is invoked after the device
has been removed via the vPHBs shutdown hook. An example of this
scenario would be an EEH reset failure while a reboot/shutdown is in
progress.

To solve both problems, the shutdown hook for cxlflash is updated to
simply remove the device. This path already includes the AFU
notification and thus this solution will continue to perform the
original intent. At the same time, the remove hook is updated to protect
against being called when the device is not enabled.

Fixes: 704c4b0ddc ("cxlflash: Shutdown notify support for CXL Flash
cards")
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>
2016-09-09 07:34:58 -04:00
Uma Krishnan
bbbfae962b scsi: cxlflash: Scan host only after the port is ready for I/O
When a port link is established, the AFU sends a 'link up' interrupt.
After the link is up, corresponding initialization steps are performed
on the card. Following that, when the card is ready for I/O, the AFU
sends 'login succeeded' interrupt. Today, cxlflash invokes
scsi_scan_host() upon receipt of both interrupts.

SCSI commands sent to the port prior to the 'login succeeded' interrupt
will fail with 'port not available' error. This is not desirable.
Moreover, when async_scan is active for the host, subsequent scan calls
are terminated with error. Due to this, the scsi_scan_host() call
performed after 'login succeeded' interrupt could portentially return
error and the devices may not be scanned properly.

To avoid this problem, scsi_scan_host() should be called only after the
'login succeeded' interrupt.

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>
2016-09-09 07:34:18 -04:00
Matthew R. Ochs
de9f0b0cbb scsi: cxlflash: Remove adapter file descriptor cache
The adapter file descriptor was previously cached within the kernel for
a given context in order to support performing a close on behalf of an
application. This is no longer needed as applications are now required
to perform a close on the adapter file descriptor.

Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-23 22:23:52 -04:00
Matthew R. Ochs
cd34af40a0 scsi: cxlflash: Transition to application close model
Caching the adapter file descriptor and performing a close on behalf of
an application is a poor design. This is due to the fact that once a
file descriptor in installed, it is free to be altered without the
knowledge of the cxlflash driver. This can lead to inconsistencies
between the application and kernel. Furthermore, the nature of the
former design is more exploitable and thus should be abandoned.

To support applications performing a close on the adapter file that is
associated with a context, a new flag is introduced to the user API to
indicate to applications that they are responsible for the close
following the cleanup (detach) of a context. The documentation is also
updated to reflect this change in behavior.

Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-23 22:23:41 -04:00
Matthew R. Ochs
888baf069f scsi: cxlflash: Add kref to context
Currently, context user references are tracked via the list of LUNs that
have attached to the context. While convenient, this is not intuitive
without a deep study of the code and is inconsistent with the existing
reference tracking patterns within the kernel. This design choice can
lead to future bug injection.

To improve code comprehension and better protect against future bugs,
add explicit reference counting to contexts and migrate the context
removal code to the kref release handler.

Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-18 22:41:36 -04:00
Matthew R. Ochs
44ef38f9a2 scsi: cxlflash: Cache owning adapter within context
The context removal routine requires access to the owning adapter
structure to reset the context within the AFU as part of the tear down
sequence. In order to support kref adoption, the owning adapter must be
accessible from the release handler. As the kref framework only provides
the kref reference as the sole parameter, another means is needed to
derive the owning adapter.

As a remedy, the owning adapter reference is saved off within the
context during initialization.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-18 22:40:27 -04:00
Matthew R. Ochs
41b99e1a30 scsi: cxlflash: Avoid mutex when destroying context
Context information structures are protected by a mutex that is held
when accessing/manipulating the context. When the code that manages
these structures was authored, a decision was made to include taking the
mutex as part of the allocation/initialization sequence and also handle
the scenario where the mutex was already held when freeing the context.

While not a problem outright, this design decision has been deemed as
too flexible and the code should be made more rigid to avoid future
bugs.  In addition, further review of the code yields that the existing
mutex manipulations in both of these context management paths are
superfluous.

This commit removes the obtaining of the context mutex in the context
initialization routine and assumes the mutex is not held in the context
free path.

Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-18 22:39:45 -04:00
Linus Torvalds
0603006b45 SCSI misc on 20160805
This is seven basic fixes (plus one MAINTAINER update) which came in
 close to the merge window.
 
 Signed-off-by: James Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "This is seven basic fixes (plus one MAINTAINER update) which came in
  close to the merge window"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  ipr: Fix error return code in ipr_probe_ioa()
  fcoe: add missing destroy_workqueue() on error in fcoe_init()
  lpfc: Fix possible NULL pointer dereference
  fcoe: Use default VLAN for FIP VLAN discovery
  ipr: Wait to do async scan until scsi host is initialized
  MAINTAINERS: Update cxlflash maintainers
  cxlflash: Verify problem state area is mapped before notifying shutdown
  lpfc: fix oops in lpfc_sli4_scmd_to_wqidx_distr() from lpfc_send_taskmgmt()
2016-08-05 23:47:27 -04:00
Linus Torvalds
bad60e6f25 powerpc updates for 4.8 # 1
Highlights:
  - PowerNV PCI hotplug support.
  - Lots more Power9 support.
  - eBPF JIT support on ppc64le.
  - Lots of cxl updates.
  - Boot code consolidation.
 
 Bug fixes:
  - Fix spin_unlock_wait() from Boqun Feng
  - Fix stack pointer corruption in __tm_recheckpoint() from Michael Neuling
  - Fix multiple bugs in memory_hotplug_max() from Bharata B Rao
  - mm: Ensure "special" zones are empty from Oliver O'Halloran
  - ftrace: Separate the heuristics for checking call sites from Michael Ellerman
  - modules: Never restore r2 for a mprofile-kernel style mcount() call from Michael Ellerman
  - Fix endianness when reading TCEs from Alexey Kardashevskiy
  - start rtasd before PCI probing from Greg Kurz
  - PCI: rpaphp: Fix slot registration for multiple slots under a PHB from Tyrel Datwyler
  - powerpc/mm: Add memory barrier in __hugepte_alloc() from Sukadev Bhattiprolu
 
 Cleanups & fixes:
  - Drop support for MPIC in pseries from Rashmica Gupta
  - Define and use PPC64_ELF_ABI_v2/v1 from Michael Ellerman
  - Remove unused symbols in asm-offsets.c from Rashmica Gupta
  - Fix SRIOV not building without EEH enabled from Russell Currey
  - Remove kretprobe_trampoline_holder. from Thiago Jung Bauermann
  - Reduce log level of PCI I/O space warning from Benjamin Herrenschmidt
  - Add array bounds checking to crash_shutdown_handlers from Suraj Jitindar Singh
  - Avoid -maltivec when using clang integrated assembler from Anton Blanchard
  - Fix array overrun in ppc_rtas() syscall from Andrew Donnellan
  - Fix error return value in cmm_mem_going_offline() from Rasmus Villemoes
  - export cpu_to_core_id() from Mauricio Faria de Oliveira
  - Remove old symbols from defconfigs from Andrew Donnellan
  - Update obsolete comments in setup_32.c about entry conditions from Benjamin Herrenschmidt
  - Add comment explaining the purpose of setup_kdump_trampoline() from Benjamin Herrenschmidt
  - Merge the RELOCATABLE config entries for ppc32 and ppc64 from Kevin Hao
  - Remove RELOCATABLE_PPC32 from Kevin Hao
  - Fix .long's in tlb-radix.c to more meaningful from Balbir Singh
 
 Minor cleanups & fixes:
  - Andrew Donnellan, Anna-Maria Gleixner, Anton Blanchard, Benjamin
    Herrenschmidt, Bharata B Rao, Christophe Leroy, Colin Ian King, Geliang
    Tang, Greg Kurz, Madhavan Srinivasan, Michael Ellerman, Michael Ellerman,
    Stephen Rothwell, Stewart Smith.
 
 Freescale updates from Scott:
  - "Highlights include more 8xx optimizations, device tree updates,
    and MVME7100 support."
 
 PowerNV PCI hotplug from Gavin Shan:
  - PCI: Add pcibios_setup_bridge()
  - Override pcibios_setup_bridge()
  - Remove PCI_RESET_DELAY_US
  - Move pnv_pci_ioda_setup_opal_tce_kill() around
  - Increase PE# capacity
  - Allocate PE# in reverse order
  - Create PEs in pcibios_setup_bridge()
  - Setup PE for root bus
  - Extend PCI bridge resources
  - Make pnv_ioda_deconfigure_pe() visible
  - Dynamically release PE
  - Update bridge windows on PCI plug
  - Delay populating pdn
  - Support PCI slot ID
  - Use PCI slot reset infrastructure
  - Introduce pnv_pci_get_slot_id()
  - Functions to get/set PCI slot state
  - PCI/hotplug: PowerPC PowerNV PCI hotplug driver
  - Print correct PHB type names
 
 Power9 idle support from Shreyas B. Prabhu:
  - set power_save func after the idle states are initialized
  - Use PNV_THREAD_WINKLE macro while requesting for winkle
  - make hypervisor state restore a function
  - Rename idle_power7.S to idle_book3s.S
  - Rename reusable idle functions to hardware agnostic names
  - Make pnv_powersave_common more generic
  - abstraction for saving SPRs before entering deep idle states
  - Add platform support for stop instruction
  - cpuidle/powernv: Use CPUIDLE_STATE_MAX instead of MAX_POWERNV_IDLE_STATES
  - cpuidle/powernv: cleanup cpuidle-powernv.c
  - cpuidle/powernv: Add support for POWER ISA v3 idle states
  - Use deepest stop state when cpu is offlined
 
 Power9 PMU from Madhavan Srinivasan:
  - factor out power8 pmu macros and defines
  - factor out power8 pmu functions
  - factor out power8 __init_pmu code
  - Add power9 event list macros for generic and cache events
  - Power9 PMU support
  - Export Power9 generic and cache events to sysfs
 
 Power9 preliminary interrupt & PCI support from Benjamin Herrenschmidt:
  - Add XICS emulation APIs
  - Move a few exception common handlers to make room
  - Add support for HV virtualization interrupts
  - Add mechanism to force a replay of interrupts
  - Add ICP OPAL backend
  - Discover IODA3 PHBs
  - pci: Remove obsolete SW invalidate
  - opal: Add real mode call wrappers
  - Rename TCE invalidation calls
  - Remove SWINV constants and obsolete TCE code
  - Rework accessing the TCE invalidate register
  - Fallback to OPAL for TCE invalidations
  - Use the device-tree to get available range of M64's
  - Check status of a PHB before using it
  - pci: Don't try to allocate resources that will be reassigned
 
 Other Power9:
  - Send SIGBUS on unaligned copy and paste from Chris Smart
  - Large Decrementer support from Oliver O'Halloran
  - Load Monitor Register Support from Jack Miller
 
 Performance improvements from Anton Blanchard:
  - Avoid load hit store in __giveup_fpu() and __giveup_altivec()
  - Avoid load hit store in setup_sigcontext()
  - Remove assembly versions of strcpy, strcat, strlen and strcmp
  - Align hot loops of some string functions
 
 eBPF JIT from Naveen N. Rao:
  - Fix/enhance 32-bit Load Immediate implementation
  - Optimize 64-bit Immediate loads
  - Introduce rotate immediate instructions
  - A few cleanups
  - Isolate classic BPF JIT specifics into a separate header
  - Implement JIT compiler for extended BPF
 
 Operator Panel driver from Suraj Jitindar Singh:
  - devicetree/bindings: Add binding for operator panel on FSP machines
  - Add inline function to get rc from an ASYNC_COMP opal_msg
  - Add driver for operator panel on FSP machines
 
 Sparse fixes from Daniel Axtens:
  - make some things static
  - Introduce asm-prototypes.h
  - Include headers containing prototypes
  - Use #ifdef __BIG_ENDIAN__ #else for REG_BYTE
  - kvm: Clarify __user annotations
  - Pass endianness to sparse
  - Make ppc_md.{halt, restart} __noreturn
 
 MM fixes & cleanups from Aneesh Kumar K.V:
  - radix: Update LPCR HR bit as per ISA
  - use _raw variant of page table accessors
  - Compile out radix related functions if RADIX_MMU is disabled
  - Clear top 16 bits of va only on older cpus
  - Print formation regarding the the MMU mode
  - hash: Update SDR1 size encoding as documented in ISA 3.0
  - radix: Update PID switch sequence
  - radix: Update machine call back to support new HCALL.
  - radix: Add LPID based tlb flush helpers
  - radix: Add a kernel command line to disable radix
  - Cleanup LPCR defines
 
 Boot code consolidation from Benjamin Herrenschmidt:
  - Move epapr_paravirt_early_init() to early_init_devtree()
  - cell: Don't use flat device-tree after boot
  - ge_imp3a: Don't use the flat device-tree after boot
  - mpc85xx_ds: Don't use the flat device-tree after boot
  - mpc85xx_rdb: Don't use the flat device-tree after boot
  - Don't test for machine type in rtas_initialize()
  - Don't test for machine type in smp_setup_cpu_maps()
  - dt: Add of_device_compatible_match()
  - Factor do_feature_fixup calls
  - Move 64-bit feature fixup earlier
  - Move 64-bit memory reserves to setup_arch()
  - Use a cachable DART
  - Move FW feature probing out of pseries probe()
  - Put exception configuration in a common place
  - Remove early allocation of the SMU command buffer
  - Move MMU backend selection out of platform code
  - pasemi: Remove IOBMAP allocation from platform probe()
  - mm/hash: Don't use machine_is() early during boot
  - Don't test for machine type to detect HEA special case
  - pmac: Remove spurrious machine type test
  - Move hash table ops to a separate structure
  - Ensure that ppc_md is empty before probing for machine type
  - Move 64-bit probe_machine() to later in the boot process
  - Move 32-bit probe() machine to later in the boot process
  - Get rid of ppc_md.init_early()
  - Move the boot time info banner to a separate function
  - Move setting of {i,d}cache_bsize to initialize_cache_info()
  - Move the content of setup_system() to setup_arch()
  - Move cache info inits to a separate function
  - Re-order the call to smp_setup_cpu_maps()
  - Re-order setup_panic()
  - Make a few boot functions __init
  - Merge 32-bit and 64-bit setup_arch()
 
 Other new features:
  - tty/hvc: Use IRQF_SHARED for OPAL hvc consoles from Sam Mendoza-Jonas
  - tty/hvc: Use opal irqchip interface if available from Sam Mendoza-Jonas
  - powerpc: Add module autoloading based on CPU features from Alastair D'Silva
  - crypto: vmx - Convert to CPU feature based module autoloading from Alastair D'Silva
  - Wake up kopald polling thread before waiting for events from Benjamin Herrenschmidt
  - xmon: Dump ISA 2.06 SPRs from Michael Ellerman
  - xmon: Dump ISA 2.07 SPRs from Michael Ellerman
  - Add a parameter to disable 1TB segs from Oliver O'Halloran
  - powerpc/boot: Add OPAL console to epapr wrappers from Oliver O'Halloran
  - Assign fixed PHB number based on device-tree properties from Guilherme G. Piccoli
  - pseries: Add pseries hotplug workqueue from John Allen
  - pseries: Add support for hotplug interrupt source from John Allen
  - pseries: Use kernel hotplug queue for PowerVM hotplug events from John Allen
  - pseries: Move property cloning into its own routine from Nathan Fontenot
  - pseries: Dynamic add entires to associativity lookup array from Nathan Fontenot
  - pseries: Auto-online hotplugged memory from Nathan Fontenot
  - pseries: Remove call to memblock_add() from Nathan Fontenot
 
 cxl:
  - Add set and get private data to context struct from Michael Neuling
  - make base more explicitly non-modular from Paul Gortmaker
  - Use for_each_compatible_node() macro from Wei Yongjun
  - Frederic Barrat
    - Abstract the differences between the PSL and XSL
    - Make vPHB device node match adapter's
  - Philippe Bergheaud
    - Add mechanism for delivering AFU driver specific events
    - Ignore CAPI adapters misplaced in switched slots
    - Refine slice error debug messages
  - Andrew Donnellan
    - static-ify variables to fix sparse warnings
    - PCI/hotplug: pnv_php: export symbols and move struct types needed by cxl
    - PCI/hotplug: pnv_php: handle OPAL_PCI_SLOT_OFFLINE power state
    - Add cxl_check_and_switch_mode() API to switch bi-modal cards
    - remove dead Kconfig options
    - fix potential NULL dereference in free_adapter()
  - Ian Munsie
    - Update process element after allocating interrupts
    - Add support for CAPP DMA mode
    - Fix allowing bogus AFU descriptors with 0 maximum processes
    - Fix allocating a minimum of 2 pages for the SPA
    - Fix bug where AFU disable operation had no effect
    - Workaround XSL bug that does not clear the RA bit after a reset
    - Fix NULL pointer dereference on kernel contexts with no AFU interrupts
    - powerpc/powernv: Split cxl code out into a separate file
    - Add cxl_slot_is_supported API
    - Enable bus mastering for devices using CAPP DMA mode
    - Move cxl_afu_get / cxl_afu_put to base
    - Allow a default context to be associated with an external pci_dev
    - Do not create vPHB if there are no AFU configuration records
    - powerpc/powernv: Add support for the cxl kernel api on the real phb
    - Add support for using the kernel API with a real PHB
    - Add kernel APIs to get & set the max irqs per context
    - Add preliminary workaround for CX4 interrupt limitation
    - Add support for interrupts on the Mellanox CX4
    - Workaround PE=0 hardware limitation in Mellanox CX4
    - powerpc/powernv: Fix pci-cxl.c build when CONFIG_MODULES=n
 
 selftests:
  - Test unaligned copy and paste from Chris Smart
  - Load Monitor Register Tests from Jack Miller
  - Cyril Bur
    - exec() with suspended transaction
    - Use signed long to read perf_event_paranoid
    - Fix usage message in context_switch
    - Fix generation of vector instructions/types in context_switch
  - Michael Ellerman
    - Use "Delta" rather than "Error" in normal output
    - Import Anton's mmap & futex micro benchmarks
    - Add a test for PROT_SAO
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Merge tag 'powerpc-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights:
   - PowerNV PCI hotplug support.
   - Lots more Power9 support.
   - eBPF JIT support on ppc64le.
   - Lots of cxl updates.
   - Boot code consolidation.

  Bug fixes:
   - Fix spin_unlock_wait() from Boqun Feng
   - Fix stack pointer corruption in __tm_recheckpoint() from Michael
     Neuling
   - Fix multiple bugs in memory_hotplug_max() from Bharata B Rao
   - mm: Ensure "special" zones are empty from Oliver O'Halloran
   - ftrace: Separate the heuristics for checking call sites from
     Michael Ellerman
   - modules: Never restore r2 for a mprofile-kernel style mcount() call
     from Michael Ellerman
   - Fix endianness when reading TCEs from Alexey Kardashevskiy
   - start rtasd before PCI probing from Greg Kurz
   - PCI: rpaphp: Fix slot registration for multiple slots under a PHB
     from Tyrel Datwyler
   - powerpc/mm: Add memory barrier in __hugepte_alloc() from Sukadev
     Bhattiprolu

  Cleanups & fixes:
   - Drop support for MPIC in pseries from Rashmica Gupta
   - Define and use PPC64_ELF_ABI_v2/v1 from Michael Ellerman
   - Remove unused symbols in asm-offsets.c from Rashmica Gupta
   - Fix SRIOV not building without EEH enabled from Russell Currey
   - Remove kretprobe_trampoline_holder from Thiago Jung Bauermann
   - Reduce log level of PCI I/O space warning from Benjamin
     Herrenschmidt
   - Add array bounds checking to crash_shutdown_handlers from Suraj
     Jitindar Singh
   - Avoid -maltivec when using clang integrated assembler from Anton
     Blanchard
   - Fix array overrun in ppc_rtas() syscall from Andrew Donnellan
   - Fix error return value in cmm_mem_going_offline() from Rasmus
     Villemoes
   - export cpu_to_core_id() from Mauricio Faria de Oliveira
   - Remove old symbols from defconfigs from Andrew Donnellan
   - Update obsolete comments in setup_32.c about entry conditions from
     Benjamin Herrenschmidt
   - Add comment explaining the purpose of setup_kdump_trampoline() from
     Benjamin Herrenschmidt
   - Merge the RELOCATABLE config entries for ppc32 and ppc64 from Kevin
     Hao
   - Remove RELOCATABLE_PPC32 from Kevin Hao
   - Fix .long's in tlb-radix.c to more meaningful from Balbir Singh

  Minor cleanups & fixes:
   - Andrew Donnellan, Anna-Maria Gleixner, Anton Blanchard, Benjamin
     Herrenschmidt, Bharata B Rao, Christophe Leroy, Colin Ian King,
     Geliang Tang, Greg Kurz, Madhavan Srinivasan, Michael Ellerman,
     Michael Ellerman, Stephen Rothwell, Stewart Smith.

  Freescale updates from Scott:
   - "Highlights include more 8xx optimizations, device tree updates,
     and MVME7100 support."

  PowerNV PCI hotplug from Gavin Shan:
   - PCI: Add pcibios_setup_bridge()
   - Override pcibios_setup_bridge()
   - Remove PCI_RESET_DELAY_US
   - Move pnv_pci_ioda_setup_opal_tce_kill() around
   - Increase PE# capacity
   - Allocate PE# in reverse order
   - Create PEs in pcibios_setup_bridge()
   - Setup PE for root bus
   - Extend PCI bridge resources
   - Make pnv_ioda_deconfigure_pe() visible
   - Dynamically release PE
   - Update bridge windows on PCI plug
   - Delay populating pdn
   - Support PCI slot ID
   - Use PCI slot reset infrastructure
   - Introduce pnv_pci_get_slot_id()
   - Functions to get/set PCI slot state
   - PCI/hotplug: PowerPC PowerNV PCI hotplug driver
   - Print correct PHB type names

  Power9 idle support from Shreyas B. Prabhu:
   - set power_save func after the idle states are initialized
   - Use PNV_THREAD_WINKLE macro while requesting for winkle
   - make hypervisor state restore a function
   - Rename idle_power7.S to idle_book3s.S
   - Rename reusable idle functions to hardware agnostic names
   - Make pnv_powersave_common more generic
   - abstraction for saving SPRs before entering deep idle states
   - Add platform support for stop instruction
   - cpuidle/powernv: Use CPUIDLE_STATE_MAX instead of MAX_POWERNV_IDLE_STATES
   - cpuidle/powernv: cleanup cpuidle-powernv.c
   - cpuidle/powernv: Add support for POWER ISA v3 idle states
   - Use deepest stop state when cpu is offlined

  Power9 PMU from Madhavan Srinivasan:
   - factor out power8 pmu macros and defines
   - factor out power8 pmu functions
   - factor out power8 __init_pmu code
   - Add power9 event list macros for generic and cache events
   - Power9 PMU support
   - Export Power9 generic and cache events to sysfs

  Power9 preliminary interrupt & PCI support from Benjamin Herrenschmidt:
   - Add XICS emulation APIs
   - Move a few exception common handlers to make room
   - Add support for HV virtualization interrupts
   - Add mechanism to force a replay of interrupts
   - Add ICP OPAL backend
   - Discover IODA3 PHBs
   - pci: Remove obsolete SW invalidate
   - opal: Add real mode call wrappers
   - Rename TCE invalidation calls
   - Remove SWINV constants and obsolete TCE code
   - Rework accessing the TCE invalidate register
   - Fallback to OPAL for TCE invalidations
   - Use the device-tree to get available range of M64's
   - Check status of a PHB before using it
   - pci: Don't try to allocate resources that will be reassigned

  Other Power9:
   - Send SIGBUS on unaligned copy and paste from Chris Smart
   - Large Decrementer support from Oliver O'Halloran
   - Load Monitor Register Support from Jack Miller

  Performance improvements from Anton Blanchard:
   - Avoid load hit store in __giveup_fpu() and __giveup_altivec()
   - Avoid load hit store in setup_sigcontext()
   - Remove assembly versions of strcpy, strcat, strlen and strcmp
   - Align hot loops of some string functions

  eBPF JIT from Naveen N. Rao:
   - Fix/enhance 32-bit Load Immediate implementation
   - Optimize 64-bit Immediate loads
   - Introduce rotate immediate instructions
   - A few cleanups
   - Isolate classic BPF JIT specifics into a separate header
   - Implement JIT compiler for extended BPF

  Operator Panel driver from Suraj Jitindar Singh:
   - devicetree/bindings: Add binding for operator panel on FSP machines
   - Add inline function to get rc from an ASYNC_COMP opal_msg
   - Add driver for operator panel on FSP machines

  Sparse fixes from Daniel Axtens:
   - make some things static
   - Introduce asm-prototypes.h
   - Include headers containing prototypes
   - Use #ifdef __BIG_ENDIAN__ #else for REG_BYTE
   - kvm: Clarify __user annotations
   - Pass endianness to sparse
   - Make ppc_md.{halt, restart} __noreturn

  MM fixes & cleanups from Aneesh Kumar K.V:
   - radix: Update LPCR HR bit as per ISA
   - use _raw variant of page table accessors
   - Compile out radix related functions if RADIX_MMU is disabled
   - Clear top 16 bits of va only on older cpus
   - Print formation regarding the the MMU mode
   - hash: Update SDR1 size encoding as documented in ISA 3.0
   - radix: Update PID switch sequence
   - radix: Update machine call back to support new HCALL.
   - radix: Add LPID based tlb flush helpers
   - radix: Add a kernel command line to disable radix
   - Cleanup LPCR defines

  Boot code consolidation from Benjamin Herrenschmidt:
   - Move epapr_paravirt_early_init() to early_init_devtree()
   - cell: Don't use flat device-tree after boot
   - ge_imp3a: Don't use the flat device-tree after boot
   - mpc85xx_ds: Don't use the flat device-tree after boot
   - mpc85xx_rdb: Don't use the flat device-tree after boot
   - Don't test for machine type in rtas_initialize()
   - Don't test for machine type in smp_setup_cpu_maps()
   - dt: Add of_device_compatible_match()
   - Factor do_feature_fixup calls
   - Move 64-bit feature fixup earlier
   - Move 64-bit memory reserves to setup_arch()
   - Use a cachable DART
   - Move FW feature probing out of pseries probe()
   - Put exception configuration in a common place
   - Remove early allocation of the SMU command buffer
   - Move MMU backend selection out of platform code
   - pasemi: Remove IOBMAP allocation from platform probe()
   - mm/hash: Don't use machine_is() early during boot
   - Don't test for machine type to detect HEA special case
   - pmac: Remove spurrious machine type test
   - Move hash table ops to a separate structure
   - Ensure that ppc_md is empty before probing for machine type
   - Move 64-bit probe_machine() to later in the boot process
   - Move 32-bit probe() machine to later in the boot process
   - Get rid of ppc_md.init_early()
   - Move the boot time info banner to a separate function
   - Move setting of {i,d}cache_bsize to initialize_cache_info()
   - Move the content of setup_system() to setup_arch()
   - Move cache info inits to a separate function
   - Re-order the call to smp_setup_cpu_maps()
   - Re-order setup_panic()
   - Make a few boot functions __init
   - Merge 32-bit and 64-bit setup_arch()

  Other new features:
   - tty/hvc: Use IRQF_SHARED for OPAL hvc consoles from Sam Mendoza-Jonas
   - tty/hvc: Use opal irqchip interface if available from Sam Mendoza-Jonas
   - powerpc: Add module autoloading based on CPU features from Alastair D'Silva
   - crypto: vmx - Convert to CPU feature based module autoloading from Alastair D'Silva
   - Wake up kopald polling thread before waiting for events from Benjamin Herrenschmidt
   - xmon: Dump ISA 2.06 SPRs from Michael Ellerman
   - xmon: Dump ISA 2.07 SPRs from Michael Ellerman
   - Add a parameter to disable 1TB segs from Oliver O'Halloran
   - powerpc/boot: Add OPAL console to epapr wrappers from Oliver O'Halloran
   - Assign fixed PHB number based on device-tree properties from Guilherme G. Piccoli
   - pseries: Add pseries hotplug workqueue from John Allen
   - pseries: Add support for hotplug interrupt source from John Allen
   - pseries: Use kernel hotplug queue for PowerVM hotplug events from John Allen
   - pseries: Move property cloning into its own routine from Nathan Fontenot
   - pseries: Dynamic add entires to associativity lookup array from Nathan Fontenot
   - pseries: Auto-online hotplugged memory from Nathan Fontenot
   - pseries: Remove call to memblock_add() from Nathan Fontenot

  cxl:
   - Add set and get private data to context struct from Michael Neuling
   - make base more explicitly non-modular from Paul Gortmaker
   - Use for_each_compatible_node() macro from Wei Yongjun
   - Frederic Barrat
   - Abstract the differences between the PSL and XSL
   - Make vPHB device node match adapter's
   - Philippe Bergheaud
   - Add mechanism for delivering AFU driver specific events
   - Ignore CAPI adapters misplaced in switched slots
   - Refine slice error debug messages
   - Andrew Donnellan
   - static-ify variables to fix sparse warnings
   - PCI/hotplug: pnv_php: export symbols and move struct types needed by cxl
   - PCI/hotplug: pnv_php: handle OPAL_PCI_SLOT_OFFLINE power state
   - Add cxl_check_and_switch_mode() API to switch bi-modal cards
   - remove dead Kconfig options
   - fix potential NULL dereference in free_adapter()
   - Ian Munsie
   - Update process element after allocating interrupts
   - Add support for CAPP DMA mode
   - Fix allowing bogus AFU descriptors with 0 maximum processes
   - Fix allocating a minimum of 2 pages for the SPA
   - Fix bug where AFU disable operation had no effect
   - Workaround XSL bug that does not clear the RA bit after a reset
   - Fix NULL pointer dereference on kernel contexts with no AFU interrupts
   - powerpc/powernv: Split cxl code out into a separate file
   - Add cxl_slot_is_supported API
   - Enable bus mastering for devices using CAPP DMA mode
   - Move cxl_afu_get / cxl_afu_put to base
   - Allow a default context to be associated with an external pci_dev
   - Do not create vPHB if there are no AFU configuration records
   - powerpc/powernv: Add support for the cxl kernel api on the real phb
   - Add support for using the kernel API with a real PHB
   - Add kernel APIs to get & set the max irqs per context
   - Add preliminary workaround for CX4 interrupt limitation
   - Add support for interrupts on the Mellanox CX4
   - Workaround PE=0 hardware limitation in Mellanox CX4
   - powerpc/powernv: Fix pci-cxl.c build when CONFIG_MODULES=n

  selftests:
   - Test unaligned copy and paste from Chris Smart
   - Load Monitor Register Tests from Jack Miller
   - Cyril Bur
   - exec() with suspended transaction
   - Use signed long to read perf_event_paranoid
   - Fix usage message in context_switch
   - Fix generation of vector instructions/types in context_switch
   - Michael Ellerman
   - Use "Delta" rather than "Error" in normal output
   - Import Anton's mmap & futex micro benchmarks
   - Add a test for PROT_SAO"

* tag 'powerpc-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (263 commits)
  powerpc/mm: Parenthesise IS_ENABLED() in if condition
  tty/hvc: Use opal irqchip interface if available
  tty/hvc: Use IRQF_SHARED for OPAL hvc consoles
  selftests/powerpc: exec() with suspended transaction
  powerpc: Improve comment explaining why we modify VRSAVE
  powerpc/mm: Drop unused externs for hpte_init_beat[_v3]()
  powerpc/mm: Rename hpte_init_lpar() and move the fallback to a header
  powerpc/mm: Fix build break when PPC_NATIVE=n
  crypto: vmx - Convert to CPU feature based module autoloading
  powerpc: Add module autoloading based on CPU features
  powerpc/powernv/ioda: Fix endianness when reading TCEs
  powerpc/mm: Add memory barrier in __hugepte_alloc()
  powerpc/modules: Never restore r2 for a mprofile-kernel style mcount() call
  powerpc/ftrace: Separate the heuristics for checking call sites
  powerpc: Merge 32-bit and 64-bit setup_arch()
  powerpc/64: Make a few boot functions __init
  powerpc: Re-order setup_panic()
  powerpc: Re-order the call to smp_setup_cpu_maps()
  powerpc/32: Move cache info inits to a separate function
  powerpc/64: Move the content of setup_system() to setup_arch()
  ...
2016-07-30 21:01:36 -07:00
Uma Krishnan
1bd2b2823e cxlflash: Verify problem state area is mapped before notifying shutdown
If an EEH or some other hard error occurs while the adapter instance was
being initialized, on the subsequent shutdown of the device, the system
could crash with:

[c000000f1da03b60] c0000000005eccfc pci_device_shutdown+0x6c/0x100
[c000000f1da03ba0] c0000000006d67d4 device_shutdown+0x1b4/0x2c0
[c000000f1da03c40] c0000000000ea30c kernel_restart_prepare+0x5c/0x80
[c000000f1da03c70] c0000000000ea48c kernel_restart+0x2c/0xc0
[c000000f1da03ce0] c0000000000ea970 SyS_reboot+0x1c0/0x2d0
[c000000f1da03e30] c000000000009204 system_call+0x38/0xb4

This crash is due to the AFU not being mapped when the shutdown
notification routine is called and is a regression that was inserted
recently with Commit 704c4b0ddc ("cxlflash: Shutdown notify support
for CXL Flash cards").

As a fix, shutdown notification should only occur when the AFU is
mapped.

Fixes: 704c4b0ddc ("cxlflash: Shutdown notify support for CXL Flash cards")
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-07-27 00:32:06 -04:00
Andrew Donnellan
1e44727a0b cxl: remove dead Kconfig options
Remove the CXL_KERNEL_API and CXL_EEH Kconfig options, as they were only
needed to coordinate the merging of the cxlflash driver. Also remove the
stub implementation of cxl_perst_reloads_same_image() in cxlflash which is
only used if CXL_EEH isn't defined (i.e. never).

Suggested-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-19 20:12:29 +10:00
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
Uma Krishnan
96e1b660fa cxlflash: Add device dependent flags
Device dependent flags are needed to support functions that are specific
to a particular device.

One such case is - some CXL Flash cards need to be notified of device
shutdown. For other CXL devices, this feature does not prove to be
useful yet. Such distinct features need to be identified in the driver
to bypass or invoke specific functionality.

In this patch, a member 'flags' has been added to device dependent
values. These flags will be used and expanded in the future to support
various device specific functions.

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
Manoj N. Kumar
f411396d94 cxlflash: Fix to drain operations from previous reset
While running 'sg_reset -H' in a loop with a user-space application active,
hit the following exception:

cpu 0x2: Vector: 300 (Data Access)
    pc: : afu_attach+0x50/0x240 [cxlflash]
    lr: : cxlflash_afu_recover+0x3dc/0x7d0 [cxlflash]
    pid   = 20365, comm = run_block_fvt

Linux version 4.5.0-491-26f710d+

cxlflash_afu_recover+0x3dc/0x7d0 [cxlflash]
cxlflash_ioctl+0x5a8/0x6f0 [cxlflash]
scsi_ioctl+0x3b0/0x4c0
sd_ioctl+0x110/0x190
blkdev_ioctl+0x28c/0xc20
block_ioctl+0xa4/0xd0
do_vfs_ioctl+0xd8/0x8c0
SyS_ioctl+0xd4/0xf0
system_call+0x38/0xb4

The problem here is that the problem space area is unmapped while the
application issues the DK_CXLFLASH_RECOVER_AFU ioctl.

This is the order I observe:

proc1				proc2
1) sg_reset
				2) ioctl(DK_CXLFLASH_RECOVER_AFU)
3) sg_reset again
   causing a PSA unmap
				4) continues RECOVER_AFU processing

The resolution to this problem is to have the reset handler drain all
outstanding user space initiated ioctls before proceeding.  It is safe
to drain after the state has been changed to STATE_RESET. Also since
drain_ioctls() was static, it had to be moved up a bit to be before
cxlflash_eh_host_reset_handler().

Signed-off-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
Manoj N. Kumar
635f6b0893 cxlflash: Fix to resolve dead-lock during EEH recovery
When a cxlflash adapter goes into EEH recovery and multiple processes
(each having established its own context) are active, the EEH recovery
can hang if the processes attempt to recover in parallel. The symptom
logged after a couple of minutes is:

INFO: task eehd:48 blocked for more than 120 seconds.
Not tainted 4.5.0-491-26f710d+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
eehd            0    48      2
Call Trace:
__switch_to+0x2f0/0x410
__schedule+0x300/0x980
schedule+0x48/0xc0
rwsem_down_write_failed+0x294/0x410
down_write+0x88/0xb0
cxlflash_pci_error_detected+0x100/0x1c0 [cxlflash]
cxl_vphb_error_detected+0x88/0x110 [cxl]
cxl_pci_error_detected+0xb0/0x1d0 [cxl]
eeh_report_error+0xbc/0x130
eeh_pe_dev_traverse+0x94/0x160
eeh_handle_normal_event+0x17c/0x450
eeh_handle_event+0x184/0x370
eeh_event_handler+0x1c8/0x1d0
kthread+0x110/0x130
ret_from_kernel_thread+0x5c/0xa4
INFO: task blockio:33215 blocked for more than 120 seconds.

Not tainted 4.5.0-491-26f710d+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blockio         0 33215  33213
Call Trace:
0x1 (unreliable)
__switch_to+0x2f0/0x410
__schedule+0x300/0x980
schedule+0x48/0xc0
rwsem_down_read_failed+0x124/0x1d0
down_read+0x68/0x80
cxlflash_ioctl+0x70/0x6f0 [cxlflash]
scsi_ioctl+0x3b0/0x4c0
sg_ioctl+0x960/0x1010
do_vfs_ioctl+0xd8/0x8c0
SyS_ioctl+0xd4/0xf0
system_call+0x38/0xb4
INFO: task eehd:48 blocked for more than 120 seconds.

The hang is because of a 3 way dead-lock:

Process A holds the recovery mutex, and waits for eehd to complete.
Process B holds the semaphore and waits for the recovery mutex.
eehd waits for semaphore.

The fix is to have Process B above release the semaphore before
attempting to acquire the recovery mutex. This will allow
eehd to proceed to completion.

Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-05-05 21:02:17 -04:00
James Bottomley
6ea7e3873e Merge branch 'fixes-base' into fixes 2016-04-05 06:56:47 -04:00
Manoj N. Kumar
ea76543127 cxlflash: Move to exponential back-off when cmd_room is not available
While profiling the cxlflash_queuecommand() path under a heavy load it
was found that number of retries to find cmd_room was fairly high.

There are two problems with the current back-off:
a) It starts with a udelay of 0
b) It backs-off linearly

Tried several approaches (a higher multiple 10*n, 100*n, as well as n^2,
2^n) and found that the exponential back-off(2^n) approach had the least
overall cost. Cost as being defined as overall time spent waiting.

The fix is to change the linear back-off to an exponential back-off.
This solution also takes care of the problem with the initial
delay (starts with 1 usec).

Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-28 20:43:34 -04:00
Manoj N. Kumar
9526f36026 cxlflash: Fix regression issue with re-ordering patch
While running 'sg_reset -H' back to back the following exception was seen:

[  735.115695] Faulting instruction address: 0xd0000000098c0864
cpu 0x0: Vector: 300 (Data Access) at [c000000ffffafa80]
    pc: d0000000098c0864: cxlflash_async_err_irq+0x84/0x5c0 [cxlflash]
    lr: c00000000013aed0: handle_irq_event_percpu+0xa0/0x310
    sp: c000000ffffafd00
   msr: 9000000000009033
   dar: 2010000
 dsisr: 40000000
  current = 0xc000000001510880
  paca    = 0xc00000000fb80000   softe: 0        irq_happened: 0x01
    pid   = 0, comm = swapper/0

Linux version 4.5.0-491-26f710d+

enter ? for help
[c000000ffffafe10] c00000000013aed0 handle_irq_event_percpu+0xa0/0x310
[c000000ffffafed0] c00000000013b1a8 handle_irq_event+0x68/0xc0
[c000000ffffaff00] c0000000001404ec handle_fasteoi_irq+0xec/0x2a0
[c000000ffffaff30] c00000000013a084 generic_handle_irq+0x54/0x80
[c000000ffffaff60] c000000000011130 __do_irq+0x80/0x1d0
[c000000ffffaff90] c000000000024d40 call_do_irq+0x14/0x24
[c000000001573a20] c000000000011318 do_IRQ+0x98/0x140
[c000000001573a70] c000000000002594 hardware_interrupt_common+0x114/0x180

This exception is being hit because the async_err interrupt path performs
an MMIO to read the interrupt status register. The MMIO region in this
case is not available.

Commit 6ded8b3cbd ("cxlflash: Unmap problem state area before detaching
master context") re-ordered the sequence in which term_mc() and stop_afu()
are called. This introduces a window for interrupts to come in with the
problem space area unmapped, that did not exist previously.

The fix is to separate the disabling of all AFU interrupts to a distinct
function, term_intr() so that it is the first thing that is done in the
tear down process.

To keep the initialization process symmetric, separate the AFU interrupt
setup also to a distinct function: init_intr().

Fixes: 6ded8b3cbd ("cxlflash: Unmap problem state area before detaching master context")
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-28 20:43:17 -04:00
Linus Torvalds
d5e2d00898 powerpc updates for 4.6
Highlights:
  - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras
  - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V
  - Add POWER9 cputable entry from Michael Neuling
  - FPU/Altivec/VSX save/restore optimisations from Cyril Bur
  - Add support for new ftrace ABI on ppc64le from Torsten Duwe
 
 Various cleanups & minor fixes from:
  - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril
    Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey,
    Sukadev Bhattiprolu, Suraj Jitindar Singh.
 
 General:
  - atomics: Allow architectures to define their own __atomic_op_* helpers from
    Boqun Feng
  - Implement atomic{, 64}_*_return_* variants and acquire/release/relaxed
    variants for (cmp)xchg from Boqun Feng
  - Add powernv_defconfig from Jeremy Kerr
  - Fix BUG_ON() reporting in real mode from Balbir Singh
  - Add xmon command to dump OPAL msglog from Andrew Donnellan
  - Add xmon command to dump process/task similar to ps(1) from Douglas Miller
  - Clean up memory hotplug failure paths from David Gibson
 
 pci/eeh:
  - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei
    Yang.
  - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
  - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
  - PCI: Add pcibios_bus_add_device() weak function from Wei Yang
  - MAINTAINERS: Update EEH details and maintainership from Russell Currey
 
 cxl:
  - Support added to the CXL driver for running on both bare-metal and
    hypervisor systems, from Christophe Lombard and Frederic Barrat.
  - Ignore probes for virtual afu pci devices from Vaibhav Jain
 
 perf:
  - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu
  - hv-24x7: Fix usage with chip events, display change in counter values,
    display domain indices in sysfs, eliminate domain suffix in event names,
    from Sukadev Bhattiprolu
 
 Freescale:
  - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum
    optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and
    other dt bits, and minor fixes/cleanup."
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Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "This was delayed a day or two by some build-breakage on old toolchains
  which we've now fixed.

  There's two PCI commits both acked by Bjorn.

  There's one commit to mm/hugepage.c which is (co)authored by Kirill.

  Highlights:
   - Restructure Linux PTE on Book3S/64 to Radix format from Paul
     Mackerras
   - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh
     Kumar K.V
   - Add POWER9 cputable entry from Michael Neuling
   - FPU/Altivec/VSX save/restore optimisations from Cyril Bur
   - Add support for new ftrace ABI on ppc64le from Torsten Duwe

  Various cleanups & minor fixes from:
   - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy,
     Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell
     Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh.

  General:
   - atomics: Allow architectures to define their own __atomic_op_*
     helpers from Boqun Feng
   - Implement atomic{, 64}_*_return_* variants and acquire/release/
     relaxed variants for (cmp)xchg from Boqun Feng
   - Add powernv_defconfig from Jeremy Kerr
   - Fix BUG_ON() reporting in real mode from Balbir Singh
   - Add xmon command to dump OPAL msglog from Andrew Donnellan
   - Add xmon command to dump process/task similar to ps(1) from Douglas
     Miller
   - Clean up memory hotplug failure paths from David Gibson

  pci/eeh:
   - Redesign SR-IOV on PowerNV to give absolute isolation between VFs
     from Wei Yang.
   - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
   - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
   - PCI: Add pcibios_bus_add_device() weak function from Wei Yang
   - MAINTAINERS: Update EEH details and maintainership from Russell
     Currey

  cxl:
   - Support added to the CXL driver for running on both bare-metal and
     hypervisor systems, from Christophe Lombard and Frederic Barrat.
   - Ignore probes for virtual afu pci devices from Vaibhav Jain

  perf:
   - Export Power8 generic and cache events to sysfs from Sukadev
     Bhattiprolu
   - hv-24x7: Fix usage with chip events, display change in counter
     values, display domain indices in sysfs, eliminate domain suffix in
     event names, from Sukadev Bhattiprolu

  Freescale:
   - Updates from Scott: "Highlights include 8xx optimizations, 32-bit
     checksum optimizations, 86xx consolidation, e5500/e6500 cpu
     hotplug, more fman and other dt bits, and minor fixes/cleanup"

* tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc: Fix unrecoverable SLB miss during restore_math()
  powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers
  powerpc/rcpm: Fix build break when SMP=n
  powerpc/book3e-64: Use hardcoded mttmr opcode
  powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible
  powerpc/T104xRDB: add tdm riser card node to device tree
  powerpc32: PAGE_EXEC required for inittext
  powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree
  powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s)
  powerpc/86xx: Introduce and use common dtsi
  powerpc/86xx: Update device tree
  powerpc/86xx: Move dts files to fsl directory
  powerpc/86xx: Switch to kconfig fragments approach
  powerpc/86xx: Update defconfigs
  powerpc/86xx: Consolidate common platform code
  powerpc32: Remove one insn in mulhdu
  powerpc32: small optimisation in flush_icache_range()
  powerpc: Simplify test in __dma_sync()
  powerpc32: move xxxxx_dcache_range() functions inline
  powerpc32: Remove clear_pages() and define clear_page() inline
  ...
2016-03-19 15:38:41 -07:00
Frederic Barrat
ca946d4e4a cxlflash: Use new cxl_pci_read_adapter_vpd() API
To read the adapter VPD, drivers can't rely on pci config APIs, as it
wouldn't work on powerVM. cxl introduced a new kernel API especially
for this, so start using it.

Co-authored-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-09 23:40:01 +11:00
Manoj N. Kumar
83430833b4 cxlflash: Increase cmd_per_lun for better throughput
With the current value of cmd_per_lun at 16, the throughput
over a single adapter is limited to around 150kIOPS.

Increase the value of cmd_per_lun to 256 to improve
throughput. With this change a single adapter is able to
attain close to the maximum throughput (380kIOPS).
Also change the number of RRQ entries that can be queued.

Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-08 21:17:33 -05:00
Manoj N. Kumar
603ecce95f cxlflash: Fix to avoid unnecessary scan with internal LUNs
When switching to the internal LUN defined on the
IBM CXL flash adapter, there is an unnecessary
scan occurring on the second port. This scan leads
to the following extra lines in the log:

Dec 17 10:09:00 tul83p1 kernel: [ 3708.561134] cxlflash 0008:00:00.0: cxlflash_queuecommand: (scp=c0000000fc1f0f00) 11/1/0/0 cdb=(A0000000-00000000-10000000-00000000)
Dec 17 10:09:00 tul83p1 kernel: [ 3708.561147] process_cmd_err: cmd failed afu_rc=32 scsi_rc=0 fc_rc=0 afu_extra=0xE, scsi_extra=0x0, fc_extra=0x0

By definition, both of the internal LUNs are on the first port/channel.

When the lun_mode is switched to internal LUN the
same value for host->max_channel is retained. This
causes an unnecessary scan over the second port/channel.

This fix alters the host->max_channel to 0 (1 port), if internal
LUNs are configured and switches it back to 1 (2 ports) while
going back to external LUNs.

Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-08 21:17:33 -05:00
Uma Krishnan
5d1952acd0 cxlflash: Reorder user context initialization
In order to support cxlflash in the PowerVM environment, underlying
hypervisor APIs have imposed a kernel API ordering change.

For the superpipe access to LUN, user applications need a context.
The cxlflash module creates this context by making a sequence of
cxl calls. In the current code, a context is initialized via
cxl_dev_context_init() followed by cxl_process_element(), a function
that obtains the process element id. Finally, cxl_start_work()
is called to attach the process element.

In the PowerVM environment, a process element id cannot be obtained
from the hypervisor until the process element is attached. The
cxlflash module is unable to create contexts without a valid
process element id.

To fix this problem, cxl_start_work() is called before obtaining
the process element id.

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>
2016-03-08 21:17:33 -05:00
Matthew R. Ochs
8a96b52af5 cxlflash: Simplify attach path error cleanup
The cxlflash_disk_attach() routine currently uses a cascading error
gate strategy for its error cleanup path. While this strategy is
commonly used to handle cleanup scenarios, it is too restrictive when
function callouts need to be restructured. Problems range from
inserting error path bugs in previously 'good' code to the cleanup
path imposing design changes to how the normal path is structured.
A less restrictive approach is needed to support ordering changes
that come about when operating in different environments.

To overcome this restriction, the error cleanup path is modified to
have a single entrypoint and use conditional logic to cleanup where
necessary. Entities that require multiple cleanup steps must be
carefully vetted to ensure their APIs support state. In cases where
they do not (none as of this commit) additional local variables can
be used to maintain state on their behalf.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-08 21:17:33 -05:00
Matthew R. Ochs
5e6632d19e cxlflash: Split out context initialization
Presently, context information structures are allocated and
initialized in the same routine, create_context(). This imposes
an ordering restriction such that all pieces of information needed
to initialize a context must be known before the context is even
allocated.

This design point is not flexible when the order of context
creation needs to be modified. Specifically, this can lead to
problems when members of the context information structure are
a part of an ordering dependency (i.e. - the 'work' structure
embedded within the context).

To remedy, the allocation is left as-is, inside of the existing
create_context() routine and the initialization is transitioned
to a new void routine, init_context(). At the same time, in
anticipation of these routines not being called in sequence, a
state boolean is added to the context information structure to
track when the context has been initilized. The context teardown
routine, destroy_context(), is modified to support being called
with a non-initialized context.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-08 21:17:33 -05:00
Uma Krishnan
6ded8b3cbd cxlflash: Unmap problem state area before detaching master context
When operating in the PowerVM environment, the cxlflash module can
receive an error from the hypervisor indicating that there are
existing mappings in the page table for the process MMIO space.

This issue exists because term_afu() currently invokes term_mc()
before stop_afu(), allowing for the master context to be detached
first and the problem state area to be unmapped second.

To resolve this issue, stop_afu() should be called before term_mc().

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>
2016-03-08 21:17:33 -05:00
Manoj N. Kumar
961487e46a cxlflash: Simplify PCI registration
The calls to pci_request_regions(), pci_resource_start(),
pci_set_dma_mask(), pci_set_master() and pci_save_state() are all
unnecessary for the IBM CXL flash adapter since data buffers
are not required to be mapped to the device's memory.

The use of services such as pci_set_dma_mask() are problematic on
hypervisor managed systems as the IBM CXL flash adapter is operating
under a virtual PCI Host Bridge (virtual PHB) which does not support
these services.

cxlflash 0001:00:00.0: init_pci: Failed to set PCI DMA mask rc=-5

The resolution is to simplify init_pci(), to a point where it does the
bare minimum (pci_enable_device). Similarly, remove the call the
pci_release_regions() from cxlflash_remove().

Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-03-08 21:17:33 -05:00
Manoj Kumar
a2746fb16e cxlflash: Enable device id for future IBM CXL adapter
This drop enables a future card with a device id of 0x0600 to be
recognized by the cxlflash driver.

As per the design, the Accelerator Function Unit (AFU) for this new IBM
CXL Flash Adapter retains the same host interface as the previous
generation. For the early prototypes of the new card, the driver with
this change behaves exactly as the driver prior to this behaved with the
earlier generation card. Therefore, no card specific programming has
been added. These card specific changes can be staged in later if
needed.

Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 20:58:29 -05:00