powerpc: replace #include <asm/export.h> with #include <linux/export.h>

Commit ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by modpost")
deprecated <asm/export.h>, which is now a wrapper of <linu

powerpc: replace #include <asm/export.h> with #include <linux/export.h>

Commit ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by modpost")
deprecated <asm/export.h>, which is now a wrapper of <linux/export.h>.

Replace #include <asm/export.h> with #include <linux/export.h>.

After all the <asm/export.h> lines are converted, <asm/export.h> and
<asm-generic/export.h> will be removed.

Signed-off-by: Masahiro Yamada <[email protected]>
[mpe: Fixup selftests that stub asm/export.h]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

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powerpc/64: asm use consistent global variable declaration and access

Use helper macros to access global variables, and place them in .data
sections rather than in .toc. Putting addresses in TOC is

powerpc/64: asm use consistent global variable declaration and access

Use helper macros to access global variables, and place them in .data
sections rather than in .toc. Putting addresses in TOC is not required
because the kernel is linked with a single TOC.

Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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powerpc: Fix __clear_user() with KUAP enabled

The KUAP implementation adds calls in clear_user() to enable and
disable access to userspace memory. However, it doesn't add these to
__clear_user(), wh

powerpc: Fix __clear_user() with KUAP enabled

The KUAP implementation adds calls in clear_user() to enable and
disable access to userspace memory. However, it doesn't add these to
__clear_user(), which is used in the ptrace regset code.

As there's only one direct user of __clear_user() (the regset code),
and the time taken to set the AMR for KUAP purposes is going to
dominate the cost of a quick access_ok(), there's not much point
having a separate path.

Rename __clear_user() to __arch_clear_user(), and make __clear_user()
just call clear_user().

Reported-by: [email protected]
Reported-by: Daniel Axtens <[email protected]>
Suggested-by: Michael Ellerman <[email protected]>
Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection")
Signed-off-by: Andrew Donnellan <[email protected]>
[mpe: Use __arch_clear_user() for the asm version like arm64 & nds32]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Richard Fontana <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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powerpc: Fix invalid use of register expressions

binutils >= 2.26 now warns about misuse of register expressions in
assembler operands that are actually literals, for example:

arch/powerpc/kernel

powerpc: Fix invalid use of register expressions

binutils >= 2.26 now warns about misuse of register expressions in
assembler operands that are actually literals, for example:

arch/powerpc/kernel/entry_64.S:535: Warning: invalid register expression

In practice these are almost all uses of r0 that should just be a
literal 0.

Signed-off-by: Andreas Schwab <[email protected]>
[mpe: Mention r0 is almost always the culprit, fold in purgatory change]
Signed-off-by: Michael Ellerman <[email protected]>

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powerpc/64: Fix naming of cache block vs. cache line

In a number of places we called "cache line size" what is actually
the cache block size, which in the powerpc architecture, means the
effective s

powerpc/64: Fix naming of cache block vs. cache line

In a number of places we called "cache line size" what is actually
the cache block size, which in the powerpc architecture, means the
effective size to use with cache management instructions (it can
be different from the actual cache line size).

We fix the naming across the board and properly retrieve both
pieces of information when available in the device-tree.

Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>

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powerpc: EX_TABLE macro for exception tables

This macro is taken from s390, and allows more flexibility in
changing exception table format.

mpe: Put it in ppc_asm.h and only define one version usin

powerpc: EX_TABLE macro for exception tables

This macro is taken from s390, and allows more flexibility in
changing exception table format.

mpe: Put it in ppc_asm.h and only define one version using
stringinfy_in_c(). Add some empty definitions and headers to keep the
selftests happy.

Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>

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ppc: move exports to definitions

Signed-off-by: Al Viro <[email protected]>

powerpc: Exported functions __clear_user and copy_page use r2 so need _GLOBAL_TOC()

__clear_user and copy_page load from the TOC and are also exported
to modules. This means we have to use _GLOBAL_T

powerpc: Exported functions __clear_user and copy_page use r2 so need _GLOBAL_TOC()

__clear_user and copy_page load from the TOC and are also exported
to modules. This means we have to use _GLOBAL_TOC() so that we
create the global entry point that sets up the TOC.

Signed-off-by: Anton Blanchard <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>

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powerpc: Optimise the 64bit optimised __clear_user

I blame Mikey for this. He elevated my slightly dubious testcase:

to benchmark status. And naturally we need to be number 1 at creating
zeros. So

powerpc: Optimise the 64bit optimised __clear_user

I blame Mikey for this. He elevated my slightly dubious testcase:

to benchmark status. And naturally we need to be number 1 at creating
zeros. So lets improve __clear_user some more.

As Paul suggests we can use dcbz for large lengths. This patch gets
the destination cacheline aligned then uses dcbz on whole cachelines.

Before:
10485760000 bytes (10 GB) copied, 0.414744 s, 25.3 GB/s

After:
10485760000 bytes (10 GB) copied, 0.268597 s, 39.0 GB/s

39 GB/s, a new record.

Signed-off-by: Anton Blanchard <[email protected]>
Tested-by: Olof Johansson <[email protected]>
Acked-by: Olof Johansson <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>

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powerpc: 64bit optimised __clear_user

I noticed __clear_user high up in a profile of one of my RAID stress
tests. The testcase was doing a dd from /dev/zero which ends up
calling __clear_user.

__cl

powerpc: 64bit optimised __clear_user

I noticed __clear_user high up in a profile of one of my RAID stress
tests. The testcase was doing a dd from /dev/zero which ends up
calling __clear_user.

__clear_user is basically a loop with a single 4 byte store which
is horribly slow. We can do much better by aligning the desination
and doing 32 bytes of 8 byte stores in a loop.

The following testcase was used to verify the patch:

http://ozlabs.org/~anton/junkcode/stress_clear_user.c

To show the improvement in performance I ran a dd from /dev/zero
to /dev/null on a POWER7 box:

Before:

# dd if=/dev/zero of=/dev/null bs=1M count=10000
10485760000 bytes (10 GB) copied, 3.72379 s, 2.8 GB/s

After:

# time dd if=/dev/zero of=/dev/null bs=1M count=10000
10485760000 bytes (10 GB) copied, 0.728318 s, 14.4 GB/s

Over 5x faster.

Signed-off-by: Anton Blanchard <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>

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