linux.git/arch/powerpc/kernel/align.c, branch v5.10 Linux kernel source tree powerpc: Use fallthrough pseudo-keyword 2020-07-29T11:09:37+00:00 Gustavo A. R. Silva gustavoars@kernel.org 2020-07-27T22:42:01+00:00 5e66a0cb5fbdc76f9ad86a1e8f43256dbad29ef7 Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200727224201.GA10133@embeddedor 
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200727224201.GA10133@embeddedor
powerpc: Define and use get_user_instr() et. al. 2020-05-18T14:10:37+00:00 Jordan Niethe jniethe5@gmail.com 2020-05-06T03:40:36+00:00 5249385ad7f0ac178433f0ae9cc5b64612c8ff77 Define specialised get_user_instr(), __get_user_instr() and __get_user_instr_inatomic() macros for reading instructions from user and/or kernel space. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Alistair Popple <alistair@popple.id.au> [mpe: Squash in addition of get_user_instr() & __user annotations] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-17-jniethe5@gmail.com 
Define specialised get_user_instr(), __get_user_instr() and
__get_user_instr_inatomic() macros for reading instructions from user
and/or kernel space.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
[mpe: Squash in addition of get_user_instr() & __user annotations]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-17-jniethe5@gmail.com
powerpc: Use a datatype for instructions 2020-05-18T14:10:37+00:00 Jordan Niethe jniethe5@gmail.com 2020-05-06T03:40:31+00:00 94afd069d937d84fb4f696eb9a78db4084e43d21 Currently unsigned ints are used to represent instructions on powerpc. This has worked well as instructions have always been 4 byte words. However, ISA v3.1 introduces some changes to instructions that mean this scheme will no longer work as well. This change is Prefixed Instructions. A prefixed instruction is made up of a word prefix followed by a word suffix to make an 8 byte double word instruction. No matter the endianness of the system the prefix always comes first. Prefixed instructions are only planned for powerpc64. Introduce a ppc_inst type to represent both prefixed and word instructions on powerpc64 while keeping it possible to exclusively have word instructions on powerpc32. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> [mpe: Fix compile error in emulate_spe()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com 
Currently unsigned ints are used to represent instructions on powerpc.
This has worked well as instructions have always been 4 byte words.

However, ISA v3.1 introduces some changes to instructions that mean
this scheme will no longer work as well. This change is Prefixed
Instructions. A prefixed instruction is made up of a word prefix
followed by a word suffix to make an 8 byte double word instruction.
No matter the endianness of the system the prefix always comes first.
Prefixed instructions are only planned for powerpc64.

Introduce a ppc_inst type to represent both prefixed and word
instructions on powerpc64 while keeping it possible to exclusively
have word instructions on powerpc32.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Fix compile error in emulate_spe()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com
powerpc: Use a function for byte swapping instructions 2020-05-18T14:10:37+00:00 Jordan Niethe jniethe5@gmail.com 2020-05-06T03:40:29+00:00 aabd2233b6aefeee6d7a2f667076d8346be1d30a Use a function for byte swapping instructions in preparation of a more complicated instruction type. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Balamuruhan S <bala24@linux.ibm.com> Link: https://lore.kernel.org/r/20200506034050.24806-10-jniethe5@gmail.com 
Use a function for byte swapping instructions in preparation of a more
complicated instruction type.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Balamuruhan S <bala24@linux.ibm.com>
Link: https://lore.kernel.org/r/20200506034050.24806-10-jniethe5@gmail.com
powerpc: Use a function for getting the instruction op code 2020-05-18T14:10:37+00:00 Jordan Niethe jniethe5@gmail.com 2020-05-06T03:40:28+00:00 8094892d1aff14269d3b7bfcd8b941217eecd81f In preparation for using a data type for instructions that can not be directly used with the '>>' operator use a function for getting the op code of an instruction. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-9-jniethe5@gmail.com 
In preparation for using a data type for instructions that can not be
directly used with the '>>' operator use a function for getting the op
code of an instruction.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-9-jniethe5@gmail.com
powerpc: Use an accessor for instructions 2020-05-18T14:10:36+00:00 Jordan Niethe jniethe5@gmail.com 2020-05-06T03:40:27+00:00 777e26f0edf8dab58b8dd474d35d83bde0ac6d76 In preparation for introducing a more complicated instruction type to accommodate prefixed instructions use an accessor for getting an instruction as a u32. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-8-jniethe5@gmail.com 
In preparation for introducing a more complicated instruction type to
accommodate prefixed instructions use an accessor for getting an
instruction as a u32.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-8-jniethe5@gmail.com
powerpc: Use a macro for creating instructions from u32s 2020-05-18T14:10:36+00:00 Jordan Niethe jniethe5@gmail.com 2020-05-06T03:40:26+00:00 753462512868674a788ecc77bb96752efb818785 In preparation for instructions having a more complex data type start using a macro, ppc_inst(), for making an instruction out of a u32. A macro is used so that instructions can be used as initializer elements. Currently this does nothing, but it will allow for creating a data type that can represent prefixed instructions. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> [mpe: Change include guard to _ASM_POWERPC_INST_H] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Alistair Popple <alistair@popple.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-7-jniethe5@gmail.com 
In preparation for instructions having a more complex data type start
using a macro, ppc_inst(), for making an instruction out of a u32.  A
macro is used so that instructions can be used as initializer elements.
Currently this does nothing, but it will allow for creating a data type
that can represent prefixed instructions.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Change include guard to _ASM_POWERPC_INST_H]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-7-jniethe5@gmail.com
powerpc/spe: Mark expected switch fall-throughs 2019-07-30T14:19:34+00:00 Michael Ellerman mpe@ellerman.id.au 2019-07-30T14:00:15+00:00 7db57e77586744af46c8bbf8f831bb2b941b7afc Mark switch cases where we are expecting to fall through. Fixes errors such as below, seen with mpc85xx_defconfig: arch/powerpc/kernel/align.c: In function 'emulate_spe': arch/powerpc/kernel/align.c:178:8: error: this statement may fall through ret |= __get_user_inatomic(temp.v[3], p++); ^~ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190730141917.21817-1-mpe@ellerman.id.au 
Mark switch cases where we are expecting to fall through.

Fixes errors such as below, seen with mpc85xx_defconfig:

  arch/powerpc/kernel/align.c: In function 'emulate_spe':
  arch/powerpc/kernel/align.c:178:8: error: this statement may fall through
    ret |= __get_user_inatomic(temp.v[3], p++);
        ^~

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190730141917.21817-1-mpe@ellerman.id.au
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30T18:26:32+00:00 Thomas Gleixner tglx@linutronix.de 2019-05-27T06:55:01+00:00 2874c5fd284268364ece81a7bd936f3c8168e567 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove 'type' argument from access_ok() function 2019-01-04T02:57:57+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-01-04T02:57:57+00:00 96d4f267e40f9509e8a66e2b39e8b95655617693 Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>