No description
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Christophe Leroy b3484a1d4d powerpc/signal: Create 'unsafe' versions of copy_[ck][fpr/vsx]_to_user()
For the non VSX version, that's trivial. Just use unsafe_copy_to_user()
instead of __copy_to_user().

For the VSX version, remove the intermediate step through a buffer and
use unsafe_put_user() directly. This generates a far smaller code which
is acceptable to inline, see below:

Standard VSX version:

0000000000000000 <.copy_fpr_to_user>:
   0:	7c 08 02 a6 	mflr    r0
   4:	fb e1 ff f8 	std     r31,-8(r1)
   8:	39 00 00 20 	li      r8,32
   c:	39 24 0b 80 	addi    r9,r4,2944
  10:	7d 09 03 a6 	mtctr   r8
  14:	f8 01 00 10 	std     r0,16(r1)
  18:	f8 21 fe 71 	stdu    r1,-400(r1)
  1c:	39 41 00 68 	addi    r10,r1,104
  20:	e9 09 00 00 	ld      r8,0(r9)
  24:	39 4a 00 08 	addi    r10,r10,8
  28:	39 29 00 10 	addi    r9,r9,16
  2c:	f9 0a 00 00 	std     r8,0(r10)
  30:	42 00 ff f0 	bdnz    20 <.copy_fpr_to_user+0x20>
  34:	e9 24 0d 80 	ld      r9,3456(r4)
  38:	3d 42 00 00 	addis   r10,r2,0
			3a: R_PPC64_TOC16_HA	.toc
  3c:	eb ea 00 00 	ld      r31,0(r10)
			3e: R_PPC64_TOC16_LO_DS	.toc
  40:	f9 21 01 70 	std     r9,368(r1)
  44:	e9 3f 00 00 	ld      r9,0(r31)
  48:	81 29 00 20 	lwz     r9,32(r9)
  4c:	2f 89 00 00 	cmpwi   cr7,r9,0
  50:	40 9c 00 18 	bge     cr7,68 <.copy_fpr_to_user+0x68>
  54:	4c 00 01 2c 	isync
  58:	3d 20 40 00 	lis     r9,16384
  5c:	79 29 07 c6 	rldicr  r9,r9,32,31
  60:	7d 3d 03 a6 	mtspr   29,r9
  64:	4c 00 01 2c 	isync
  68:	38 a0 01 08 	li      r5,264
  6c:	38 81 00 70 	addi    r4,r1,112
  70:	48 00 00 01 	bl      70 <.copy_fpr_to_user+0x70>
			70: R_PPC64_REL24	.__copy_tofrom_user
  74:	60 00 00 00 	nop
  78:	e9 3f 00 00 	ld      r9,0(r31)
  7c:	81 29 00 20 	lwz     r9,32(r9)
  80:	2f 89 00 00 	cmpwi   cr7,r9,0
  84:	40 9c 00 18 	bge     cr7,9c <.copy_fpr_to_user+0x9c>
  88:	4c 00 01 2c 	isync
  8c:	39 20 ff ff 	li      r9,-1
  90:	79 29 00 44 	rldicr  r9,r9,0,1
  94:	7d 3d 03 a6 	mtspr   29,r9
  98:	4c 00 01 2c 	isync
  9c:	38 21 01 90 	addi    r1,r1,400
  a0:	e8 01 00 10 	ld      r0,16(r1)
  a4:	eb e1 ff f8 	ld      r31,-8(r1)
  a8:	7c 08 03 a6 	mtlr    r0
  ac:	4e 80 00 20 	blr

'unsafe' simulated VSX version (The ... are only nops) using
unsafe_copy_fpr_to_user() macro:

unsigned long copy_fpr_to_user(void __user *to,
			       struct task_struct *task)
{
	unsafe_copy_fpr_to_user(to, task, failed);
	return 0;
failed:
	return 1;
}

0000000000000000 <.copy_fpr_to_user>:
   0:	39 00 00 20 	li      r8,32
   4:	39 44 0b 80 	addi    r10,r4,2944
   8:	7d 09 03 a6 	mtctr   r8
   c:	7c 69 1b 78 	mr      r9,r3
...
  20:	e9 0a 00 00 	ld      r8,0(r10)
  24:	f9 09 00 00 	std     r8,0(r9)
  28:	39 4a 00 10 	addi    r10,r10,16
  2c:	39 29 00 08 	addi    r9,r9,8
  30:	42 00 ff f0 	bdnz    20 <.copy_fpr_to_user+0x20>
  34:	e9 24 0d 80 	ld      r9,3456(r4)
  38:	f9 23 01 00 	std     r9,256(r3)
  3c:	38 60 00 00 	li      r3,0
  40:	4e 80 00 20 	blr
...
  50:	38 60 00 01 	li      r3,1
  54:	4e 80 00 20 	blr

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/29f6c4b8e7a5bbc61e6a8801b78bbf493f9f819e.1597770847.git.christophe.leroy@csgroup.eu
History 2020-12-04 01:01:14 +11:00
arch powerpc/signal: Create 'unsafe' versions of copy_[ck][fpr/vsx]_to_user() 2020-12-04 01:01:14 +11:00
block blk-mq: mark flush request as IDLE in flush_end_io() 2020-10-30 08:33:49 -06:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto drivers-5.10-2020-10-12 2020-10-13 13:04:41 -07:00
Documentation powerpc/64s: flush L1D after user accesses 2020-11-19 23:47:18 +11:00
drivers Char/Misc fixes/removals for 5.10-rc2 2020-11-01 10:05:16 -08:00
fs Driver core / Documentation fixes for 5.10-rc2 2020-11-01 09:59:13 -08:00
include signal: Add unsafe_put_compat_sigset() 2020-12-04 01:01:14 +11:00
init linux-kselftest-kunit-5.10-rc1 2020-10-18 14:45:59 -07:00
ipc ipc: adjust proc_ipc_sem_dointvec definition to match prototype 2020-09-05 12:14:29 -07:00
kernel A few fixes for timers/timekeeping: 2020-11-01 11:13:45 -08:00
lib Driver core / Documentation fixes for 5.10-rc2 2020-11-01 09:59:13 -08:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm/process_vm_access: Add missing #include <linux/compat.h> 2020-10-27 12:41:29 -07:00
net flexible-array member conversion patches for 5.10-rc2 2020-10-31 14:31:28 -07:00
samples misc: mic: remove the MIC drivers 2020-10-28 19:12:03 +01:00
scripts scripts: get_abi.pl: assume ReST format by default 2020-10-30 13:16:03 +01:00
security ima: Replace zero-length array with flexible-array member 2020-10-29 17:22:59 -05:00
sound ARM: SoC platform updates 2020-10-24 10:33:08 -07:00
tools Merge branch 'fixes' into next 2020-11-25 23:17:31 +11:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt kvm: x86/mmu: Support dirty logging for the TDP MMU 2020-10-23 03:42:13 -04:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap MAINTAINERS: jarkko.sakkinen@linux.intel.com -> jarkko@kernel.org 2020-10-16 11:11:19 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Sangbeom Kim to credits 2020-10-26 10:11:18 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Char/Misc fixes/removals for 5.10-rc2 2020-11-01 10:05:16 -08:00
Makefile Linux 5.10-rc2 2020-11-01 14:43:51 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.