Commit Graph

55 Commits

Author SHA1 Message Date
Alastair D'Silva
3591538a31 ocxl: Address kernel doc errors & warnings
This patch addresses warnings and errors from the kernel doc scripts for
the OpenCAPI driver.

It also makes minor tweaks to make the docs more consistent.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200415012343.919255-3-alastair@d-silva.org
2020-07-29 23:47:52 +10:00
Alexander A. Klimov
07497137a5 ocxl: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
	  If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
            If both the HTTP and HTTPS versions
            return 200 OK and serve the same content:
              Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200713175506.36676-1-grandmaster@al2klimov.de
2020-07-16 13:12:46 +10:00
Philippe Bergheaud
87db7579eb ocxl: control via sysfs whether the FPGA is reloaded on a link reset
Some opencapi FPGA images allow to control if the FPGA should be reloaded
on the next adapter reset. If it is supported, the image specifies it
through a Vendor Specific DVSEC in the config space of function 0.

Signed-off-by: Philippe Bergheaud <felix@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200619140439.153962-1-fbarrat@linux.ibm.com
2020-07-15 11:07:19 +10:00
Andrew Donnellan
a0594e89c9 ocxl: Fix misleading comment
In ocxl_context_free() we note that the AFU reference we're releasing
was taken in "ocxl_context_init", a function that no longer exists.

Fix it to say ocxl_context_alloc() instead, which is the new name for
ocxl_context_init(), since it was renamed.

Fixes: b9721d275c ("ocxl: Allow external drivers to use OpenCAPI contexts")
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200226043923.5481-1-ajd@linux.ibm.com
2020-05-20 23:39:57 +10:00
Frederic Barrat
49ce94b867 ocxl: Add PCI hotplug dependency to Kconfig
The PCI hotplug framework is used to update the devices when a new
image is written to the FPGA.

Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-12-fbarrat@linux.ibm.com
2020-01-23 21:31:18 +11:00
Frederic Barrat
913e73c77d ocxl: Fix potential memory leak on context creation
If we couldn't fully init a context, we were leaking memory.

Fixes: b9721d275c ("ocxl: Allow external drivers to use OpenCAPI contexts")
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191209105513.8566-1-fbarrat@linux.ibm.com
2019-12-14 07:59:39 +11:00
Frederic Barrat
a58d37bce0 ocxl: Fix concurrent AFU open and device removal
If an ocxl device is unbound through sysfs at the same time its AFU is
being opened by a user process, the open code may dereference freed
stuctures, which can lead to kernel oops messages. You'd have to hit a
tiny time window, but it's possible. It's fairly easy to test by
making the time window bigger artificially.

Fix it with a combination of 2 changes:
  - when an AFU device is found in the IDR by looking for the device
    minor number, we should hold a reference on the device until after
    the context is allocated. A reference on the AFU structure is kept
    when the context is allocated, so we can release the reference on
    the device after the context allocation.
  - with the fix above, there's still another even tinier window,
    between the time the AFU device is found in the IDR and the
    reference on the device is taken. We can fix this one by removing
    the IDR entry earlier, when the device setup is removed, instead
    of waiting for the 'release' device callback. With proper locking
    around the IDR.

Fixes: 75ca758adb ("ocxl: Create a clear delineation between ocxl backend & frontend")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190624144148.32022-1-fbarrat@linux.ibm.com
2019-12-10 20:34:23 +11:00
Nishad Kamdar
7ed42113ce ocxl: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style
in header files for Open Coherent Accelerator (OCXL) compatible device
drivers. For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used)

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Link: https://lore.kernel.org/r/20190920161826.GA6894@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-10 15:34:40 +02:00
Nicholas Piggin
2275d7b575 powerpc/64s/radix: introduce options to disable use of the tlbie instruction
Introduce two options to control the use of the tlbie instruction. A
boot time option which completely disables the kernel using the
instruction, this is currently incompatible with HASH MMU, KVM, and
coherent accelerators.

And a debugfs option can be switched at runtime and avoids using tlbie
for invalidating CPU TLBs for normal process and kernel address
mappings. Coherent accelerators are still managed with tlbie, as will
KVM partition scope translations.

Cross-CPU TLB flushing is implemented with IPIs and tlbiel. This is a
basic implementation which does not attempt to make any optimisation
beyond the tlbie implementation.

This is useful for performance testing among other things. For example
in certain situations on large systems, using IPIs may be faster than
tlbie as they can be directed rather than broadcast. Later we may also
take advantage of the IPIs to do more interesting things such as trim
the mm cpumask more aggressively.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-7-npiggin@gmail.com
2019-09-05 14:22:41 +10:00
Linus Torvalds
192f0f8e9d powerpc updates for 5.3
Notable changes:
 
  - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well
    as some other functions only used by drivers that haven't (yet?) made it
    upstream.
 
  - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e
    mem: ...) which could lead to register corruption and kernel crashes.
 
  - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc
    when using the Radix MMU.
 
  - A large but incremental rewrite of our exception handling code to use gas
    macros rather than multiple levels of nested CPP macros.
 
 And the usual small fixes, cleanups and improvements.
 
 Thanks to:
   Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju
   T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater,
   Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig,
   Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R.
   Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg
   Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
   Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao,
   Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria,
   Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun
   Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung
   Bauermann, YueHaibing.
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Merge tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver,
     as well as some other functions only used by drivers that haven't
     (yet?) made it upstream.

   - A fix for a bug in our handling of hardware watchpoints (eg. perf
     record -e mem: ...) which could lead to register corruption and
     kernel crashes.

   - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for
     vmalloc when using the Radix MMU.

   - A large but incremental rewrite of our exception handling code to
     use gas macros rather than multiple levels of nested CPP macros.

  And the usual small fixes, cleanups and improvements.

  Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab,
  Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann,
  Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe
  Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis
  Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert
  Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz,
  Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
  Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N.
  Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi
  Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher
  Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj
  Jitindar Singh, Thiago Jung Bauermann, YueHaibing"

* tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits)
  powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state.
  powerpc/eeh: Handle hugepages in ioremap space
  ocxl: Update for AFU descriptor template version 1.1
  powerpc/boot: pass CONFIG options in a simpler and more robust way
  powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
  powerpc/irq: Don't WARN continuously in arch_local_irq_restore()
  powerpc/module64: Use symbolic instructions names.
  powerpc/module32: Use symbolic instructions names.
  powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
  powerpc/module64: Fix comment in R_PPC64_ENTRY handling
  powerpc/boot: Add lzo support for uImage
  powerpc/boot: Add lzma support for uImage
  powerpc/boot: don't force gzipped uImage
  powerpc/8xx: Add microcode patch to move SMC parameter RAM.
  powerpc/8xx: Use IO accessors in microcode programming.
  powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c
  powerpc/8xx: refactor programming of microcode CPM params.
  powerpc/8xx: refactor printing of microcode patch name.
  powerpc/8xx: Refactor microcode write
  powerpc/8xx: refactor writing of CPM microcode arrays
  ...
2019-07-13 16:08:36 -07:00
Alastair D'Silva
73a2b047c8 ocxl: Update for AFU descriptor template version 1.1
The OpenCAPI discovery and configuration specification has been
updated and introduces version 1.1 of the AFU descriptor template,
with new fields to better define the memory layout of an OpenCAPI
adapter.

The ocxl driver doesn't do much yet to support LPC memory but as we
start seeing (non-LPC) AFU images using the new template, this patch
updates the config space parsing code to avoid spitting a warning.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190605111545.19762-1-fbarrat@linux.ibm.com
2019-07-10 13:20:44 +10:00
Alastair D'Silva
60e8523e2e ocxl: Allow contexts to be attached with a NULL mm
If an OpenCAPI context is to be used directly by a kernel driver, there
may not be a suitable mm to use.

The patch makes the mm parameter to ocxl_context_attach optional.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Link: https://lore.kernel.org/r/20190620041203.12274-1-alastair@au1.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03 21:29:47 +02:00
Greg Kroah-Hartman
0154ec71d5 Merge 5.2-rc4 into char-misc-next
We want the char/misc driver fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09 09:11:21 +02:00
YueHaibing
00b0cdbbc8 ocxl: Make ocxl_remove() static
Fix sparse warning:

drivers/misc/ocxl/pci.c:44:6: warning:
 symbol 'ocxl_remove' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-28 12:08:11 +10:00
Bartlomiej Zolnierkiewicz
dc3e0aa5c5 misc: remove redundant 'default n' from Kconfig-s
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.

Also since commit f467c5640c ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:

    ...
    One side effect of (and the main motivation for) this change is making
    the following two definitions behave exactly the same:

        config FOO
                bool

        config FOO
                bool
                default n

    With this change, neither of these will generate a
    '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
    That might make it clearer to people that a bare 'default n' is
    redundant.
    ...

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 18:00:41 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Wei Yongjun
6be6a8de1b ocxl: Fix return value check in afu_ioctl()
In case of error, the function eventfd_ctx_fdget() returns ERR_PTR() and
never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR().

This issue was detected by using the Coccinelle software.

Fixes: 0601466146 ("ocxl: move event_fd handling to frontend")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-06 20:21:56 +10:00
Alastair D'Silva
7e462c2a8a ocxl: Provide global MMIO accessors for external drivers
External drivers that communicate via OpenCAPI will need to make
MMIO calls to interact with the devices.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:02 +10:00
Alastair D'Silva
0601466146 ocxl: move event_fd handling to frontend
Event_fd is only used in the driver frontend, so it does not
need to exist in the backend code. Relocate it to the frontend
and provide an opaque mechanism for consumers instead.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:02 +10:00
Alastair D'Silva
2ec3b7ed2a ocxl: afu_irq only deals with IRQ IDs, not offsets
The use of offsets is required only in the frontend, so alter
the IRQ API to only work with IRQ IDs in the backend.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:02 +10:00
Alastair D'Silva
b9721d275c ocxl: Allow external drivers to use OpenCAPI contexts
Most OpenCAPI operations require a valid context, so
exposing these functions to external drivers is necessary.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:02 +10:00
Alastair D'Silva
75ca758adb ocxl: Create a clear delineation between ocxl backend & frontend
The OCXL driver contains both frontend code for interacting with userspace,
as well as backend code for interacting with the hardware.

This patch separates the backend code from the frontend so that it can be
used by other device drivers that communicate via OpenCAPI.

Relocate dev, cdev & sysfs files to the frontend code to allow external
drivers to maintain their own devices.

Reference counting on the device in the backend is replaced with kref
counting.

Move file & sysfs layer initialisation from core.c (backend) to
pci.c (frontend).

Create an ocxl_function oriented interface for initing devices &
enumerating AFUs.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:01 +10:00
Alastair D'Silva
2f7d3d1453 ocxl: Don't pass pci_dev around
This data is already available in a struct

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:01 +10:00
Alastair D'Silva
1ba2143606 ocxl: Split pci.c
In preparation for making core code available for external drivers,
move the core code out of pci.c and into core.c

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:01 +10:00
Alastair D'Silva
b696d28283 ocxl: Remove some unused exported symbols
Remove some unused exported symbols.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:01 +10:00
Alastair D'Silva
53e3e74530 ocxl: Remove superfluous 'extern' from headers
The 'extern' keyword adds no value here.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:01 +10:00
Alastair D'Silva
32941494ff ocxl: read_pasid never returns an error, so make it void
No need for a return value in read_pasid as it only returns 0.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:00 +10:00
Alastair D'Silva
9c4ae06456 ocxl: Rename struct link to ocxl_link
The term 'link' is ambiguous (especially when the struct is used for a
list), so rename it for clarity.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 02:55:00 +10:00
YueHaibing
32eeb5614d ocxl: remove set but not used variables 'tid' and 'lpid'
Fixes gcc '-Wunused-but-set-variable' warning:

  drivers/misc/ocxl/link.c: In function 'xsl_fault_handler':
  drivers/misc/ocxl/link.c:187:17: warning: variable 'tid' set but not used
  drivers/misc/ocxl/link.c:187:6: warning: variable 'lpid' set but not used

They are never used and can be removed.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-01 12:09:27 +10:00
Aneesh Kumar K.V
0034d395f8 powerpc/mm/hash64: Map all the kernel regions in the same 0xc range
This patch maps vmalloc, IO and vmemap regions in the 0xc address range
instead of the current 0xd and 0xf range. This brings the mapping closer
to radix translation mode.

With hash 64K page size each of this region is 512TB whereas with 4K config
we are limited by the max page table range of 64TB and hence there regions
are of 16TB size.

The kernel mapping is now:

 On 4K hash

     kernel_region_map_size = 16TB
     kernel vmalloc start   = 0xc000100000000000
     kernel IO start        = 0xc000200000000000
     kernel vmemmap start   = 0xc000300000000000

64K hash, 64K radix and 4k radix:

     kernel_region_map_size = 512TB
     kernel vmalloc start   = 0xc008000000000000
     kernel IO start        = 0xc00a000000000000
     kernel vmemmap start   = 0xc00c000000000000

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Greg Kurz
2f07229f02 ocxl: Fix endiannes bug in read_afu_name()
The AFU Descriptor Template in the PCI config space has a Name Space
field which is a 24 Byte ASCII character string of descriptive name
space for the AFU. The OCXL driver read the string four characters at
a time with pci_read_config_dword().

This optimization is valid on a little-endian system since this is PCI,
but a big-endian system ends up with each subset of four characters in
reverse order.

This could be fixed by switching to read characters one by one. Another
option is to swap the bytes if we're big-endian.

Go for the latter with le32_to_cpu().

Cc: stable@vger.kernel.org      # v4.16
Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-21 14:46:50 +11:00
Greg Kurz
d1f75a9684 ocxl/afu_irq: Don't include <asm/pnv-ocxl.h>
The AFU irq code doesn't need to reach out to the platform.

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Greg Kurz
759bc01586 ocxl: Clarify error path in setup_xsl_irq()
Implementing rollback with goto and labels is a common practice that
leads to prettier and more maintainable code. FWIW, this design pattern
is already being used in alloc_link() a few lines below in this file.

Do the same in setup_xsl_irq().

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Greg Kurz
e1e71e2017 ocxl: Fix endiannes bug in ocxl_link_update_pe()
All fields in the PE are big-endian. Use cpu_to_be32() like everywhere
else something is written to the PE. Otherwise a wrong TID will be used
by the NPU. If this TID happens to point to an existing thread sharing
the same mm, it could be woken up by error. This is highly improbable
though. The likely outcome of this is the NPU not finding the target
thread and forcing the AFU into sending an interrupt, which userspace
is supposed to handle anyway.

Fixes: e948e06fc6 ("ocxl: Expose the thread_id needed for wait on POWER9")
Cc: stable@vger.kernel.org      # v4.18
Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20 22:21:20 +11:00
Christophe Lombard
6f8e45f7eb ocxl: Fix access to the AFU Descriptor Data
The AFU Information DVSEC capability is a means to extract common,
general information about all of the AFUs associated with a Function
independent of the specific functionality that each AFU provides.
Write in the AFU Index field allows to access to the descriptor data
for each AFU.

With the current code, we are not able to access to these specific data
when the index >= 1 because we are writing to the wrong location.
All requests to the data of each AFU are pointing to those of the AFU 0,
which could have impacts when using a card with more than one AFU per
function.

This patch fixes the access to the AFU Descriptor Data indexed by the
AFU Info Index field.

Fixes: 5ef3166e8a ("ocxl: Driver code for 'generic' opencapi devices")
Cc: stable <stable@vger.kernel.org>     # 4.16
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>

Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:58:09 +10:00
Linus Torvalds
6ada4e2826 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc things

 - a few Y2038 fixes

 - ntfs fixes

 - arch/sh tweaks

 - ocfs2 updates

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (111 commits)
  mm/hmm.c: remove unused variables align_start and align_end
  fs/userfaultfd.c: remove redundant pointer uwq
  mm, vmacache: hash addresses based on pmd
  mm/list_lru: introduce list_lru_shrink_walk_irq()
  mm/list_lru.c: pass struct list_lru_node* as an argument to __list_lru_walk_one()
  mm/list_lru.c: move locking from __list_lru_walk_one() to its caller
  mm/list_lru.c: use list_lru_walk_one() in list_lru_walk_node()
  mm, swap: make CONFIG_THP_SWAP depend on CONFIG_SWAP
  mm/sparse: delete old sparse_init and enable new one
  mm/sparse: add new sparse_init_nid() and sparse_init()
  mm/sparse: move buffer init/fini to the common place
  mm/sparse: use the new sparse buffer functions in non-vmemmap
  mm/sparse: abstract sparse buffer allocations
  mm/hugetlb.c: don't zero 1GiB bootmem pages
  mm, page_alloc: double zone's batchsize
  mm/oom_kill.c: document oom_lock
  mm/hugetlb: remove gigantic page support for HIGHMEM
  mm, oom: remove sleep from under oom_lock
  kernel/dma: remove unsupported gfp_mask parameter from dma_alloc_from_contiguous()
  mm/cma: remove unsupported gfp_mask parameter from cma_alloc()
  ...
2018-08-17 16:49:31 -07:00
Souptick Joarder
50a7ca3c6f mm: convert return type of handle_mm_fault() caller to vm_fault_t
Use new return type vm_fault_t for fault handler.  For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno.  Once all instances are converted, vm_fault_t will become a
distinct type.

Ref-> commit 1c8f422059 ("mm: change return type to vm_fault_t")

In this patch all the caller of handle_mm_fault() are changed to return
vm_fault_t type.

Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: David S. Miller <davem@davemloft.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17 16:20:28 -07:00
Frederic Barrat
d497ebf5fb ocxl: Fix page fault handler in case of fault on dying process
If a process exits without doing proper cleanup, there's a window
where an opencapi device can try to access the memory of the dying
process and may trigger a page fault. That's an expected scenario and
the ocxl driver holds a reference on the mm_struct of the process
until the opencapi device is notified of the process exiting.
However, if mm_users is already at 0, i.e. the address space of the
process has already been destroyed, the driver shouldn't try resolving
the page fault, as it will fail, but it can also try accessing already
freed data.

It is fixed by only calling the bottom half of the page fault handler
if mm_users is greater than 0 and get a reference on mm_users instead
of mm_count. Otherwise, we can safely return a translation fault to
the device, as its associated memory context is being removed. The
opencapi device will be properly cleaned up shortly after when closing
the file descriptors.

Fixes: 5ef3166e8a ("ocxl: Driver code for 'generic' opencapi devices")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-By: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:59:45 +10:00
Souptick Joarder
a545cf032d ocxl: Change return type for fault handler
Use new return type vm_fault_t for fault handler. For now, this is
just documenting that the function returns a VM_FAULT value rather
than an errno. Once all instances are converted, vm_fault_t will
become a distinct type.

Ref-> commit 1c8f422059 ("mm: change return type to vm_fault_t")

There is an existing bug when vm_insert_pfn() can return ENOMEM which
was ignored and VM_FAULT_NOPAGE returned as default. The new inline
vmf_insert_pfn() has removed this inefficiency by returning correct
vm_fault_ type.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02 23:54:26 +10:00
Wei Yongjun
2e5c93d6bb ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait()
Add the missing unlock before return from function
afu_ioctl_enable_p9_wait() in the error handling case.

Fixes: e948e06fc6 ("ocxl: Expose the thread_id needed for wait on POWER9")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-05 21:33:57 +10:00
Alastair D'Silva
02a8e5bc1c ocxl: Add an IOCTL so userspace knows what OCXL features are available
In order for a userspace AFU driver to call the POWER9 specific
OCXL_IOCTL_ENABLE_P9_WAIT, it needs to verify that it can actually
make that call.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:32 +10:00
Alastair D'Silva
e948e06fc6 ocxl: Expose the thread_id needed for wait on POWER9
In order to successfully issue as_notify, an AFU needs to know the TID
to notify, which in turn means that this information should be
available in userspace so it can be communicated to the AFU.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:32 +10:00
Alastair D'Silva
19df39581c ocxl: Rename pnv_ocxl_spa_remove_pe to clarify it's action
The function removes the process element from NPU cache.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:32 +10:00
Greg Kroah-Hartman
b24d0d5b12 Merge 4.16-rc7 into char-misc-next
We want the hyperv fix in here for merging and testing.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-28 12:27:35 +02:00
Arvind Yadav
474cca5fd8 misc: ocxl: use put_device() instead of device_unregister()
if device_register() returned an error! Always use put_device()
to give up the reference initialized.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 18:12:01 +01:00
Alastair D'Silva
07c5ccd70a ocxl: Add get_metadata IOCTL to share OCXL information to userspace
Some required information is not exposed to userspace currently (eg. the
PASID), pass this information back, along with other information which
is currently communicated via sysfs, which saves some parsing effort in
userspace.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-02 13:02:14 +11:00
Frederic Barrat
423688abd9 ocxl: Fix potential bad errno on irq allocation
Fix some issues found by a static checker:

When allocating an AFU interrupt, if the driver cannot copy the output
parameters to userland, the errno value was not set to EFAULT

Remove a (now) useless cast.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-21 11:21:01 +11:00
Linus Torvalds
694a20dae6 powerpc fixes for 4.16 #2
A larger batch of fixes than we'd like. Roughly 1/3 fixes for new code, 1/3
 fixes for stable and 1/3 minor things.
 
 There's four commits fixing bugs when using 16GB huge pages on hash, caused by
 some of the preparatory changes for pkeys.
 
 Two fixes for bugs in the enhanced IRQ soft masking for local_t, one of which
 broke KVM in some circumstances.
 
 Four fixes for Power9. The most bizarre being a bug where futexes stopped
 working because a NULL pointer dereference didn't trap during early boot (it
 aliased the kernel mapping). A fix for memory hotplug when using the Radix MMU,
 and a fix for live migration of guests using the Radix MMU.
 
 Two fixes for hotplug on pseries machines. One where we weren't correctly
 updating NUMA info when CPUs are added and removed. And the other fixes
 crashes/hangs seen when doing memory hot remove during boot, which is apparently
 a thing people do.
 
 Finally a handful of build fixes for obscure configs and other minor fixes.
 
 Thanks to:
   Alexey Kardashevskiy, Aneesh Kumar K.V, Balbir Singh, Colin Ian King, Daniel
   Henrique Barboza, Florian Weimer, Guenter Roeck, Harish, Laurent Vivier,
   Madhavan Srinivasan, Mauricio Faria de Oliveira, Nathan Fontenot, Nicholas
   Piggin, Sam Bobroff.
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Merge tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "A larger batch of fixes than we'd like. Roughly 1/3 fixes for new
  code, 1/3 fixes for stable and 1/3 minor things.

  There's four commits fixing bugs when using 16GB huge pages on hash,
  caused by some of the preparatory changes for pkeys.

  Two fixes for bugs in the enhanced IRQ soft masking for local_t, one
  of which broke KVM in some circumstances.

  Four fixes for Power9. The most bizarre being a bug where futexes
  stopped working because a NULL pointer dereference didn't trap during
  early boot (it aliased the kernel mapping). A fix for memory hotplug
  when using the Radix MMU, and a fix for live migration of guests using
  the Radix MMU.

  Two fixes for hotplug on pseries machines. One where we weren't
  correctly updating NUMA info when CPUs are added and removed. And the
  other fixes crashes/hangs seen when doing memory hot remove during
  boot, which is apparently a thing people do.

  Finally a handful of build fixes for obscure configs and other minor
  fixes.

  Thanks to: Alexey Kardashevskiy, Aneesh Kumar K.V, Balbir Singh, Colin
  Ian King, Daniel Henrique Barboza, Florian Weimer, Guenter Roeck,
  Harish, Laurent Vivier, Madhavan Srinivasan, Mauricio Faria de
  Oliveira, Nathan Fontenot, Nicholas Piggin, Sam Bobroff"

* tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  selftests/powerpc: Fix to use ucontext_t instead of struct ucontext
  powerpc/kdump: Fix powernv build break when KEXEC_CORE=n
  powerpc/pseries: Fix build break for SPLPAR=n and CPU hotplug
  powerpc/mm/hash64: Zero PGD pages on allocation
  powerpc/mm/hash64: Store the slot information at the right offset for hugetlb
  powerpc/mm/hash64: Allocate larger PMD table if hugetlb config is enabled
  powerpc/mm: Fix crashes with 16G huge pages
  powerpc/mm: Flush radix process translations when setting MMU type
  powerpc/vas: Don't set uses_vas for kernel windows
  powerpc/pseries: Enable RAS hotplug events later
  powerpc/mm/radix: Split linear mapping on hot-unplug
  powerpc/64s/radix: Boot-time NULL pointer protection using a guard-PID
  ocxl: fix signed comparison with less than zero
  powerpc/64s: Fix may_hard_irq_enable() for PMI soft masking
  powerpc/64s: Fix MASKABLE_RELON_EXCEPTION_HV_OOL macro
  powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove
2018-02-14 10:06:41 -08:00
Linus Torvalds
a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Colin Ian King
dedab7f0d3 ocxl: fix signed comparison with less than zero
Currently the comparison of used < 0 is always false because
uses is a size_t. Fix this by making used a ssize_t type.

Detected by Coccinelle:
drivers/misc/ocxl/file.c:320:6-10: WARNING: Unsigned expression
compared with zero: used < 0

Fixes: 5ef3166e8a ("ocxl: Driver code for 'generic' opencapi devices")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-02-08 23:56:11 +11:00