linux/arch/x86
Linus Torvalds 92ae03f2ef x86: merge 32/64-bit versions of 'strncpy_from_user()' and speed it up
This merges the 32- and 64-bit versions of the x86 strncpy_from_user()
by just rewriting it in C rather than the ancient inline asm versions
that used lodsb/stosb and had been duplicated for (trivial) differences
between the 32-bit and 64-bit versions.

While doing that, it also speeds them up by doing the accesses a word at
a time.  Finally, the new routines also properly handle the case of
hitting the end of the address space, which we have never done correctly
before (fs/namei.c has a hack around it for that reason).

Despite all these improvements, it actually removes more lines than it
adds, due to the de-duplication.  Also, we no longer export (or define)
the legacy __strncpy_from_user() function (that was defined to not do
the user permission checks), since it's not actually used anywhere, and
the user address space checks are built in to the new code.

Other architecture maintainers have been notified that the old hack in
fs/namei.c will be going away in the 3.5 merge window, in case they
copied the x86 approach of being a bit cavalier about the end of the
address space.

Cc: linux-arch@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin" <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-11 09:41:28 -07:00
..
boot x86, boot: Correct CFLAGS for hostprogs 2012-03-22 12:42:51 -07:00
configs x86/kconfig: Remove CONFIG_TR=y from the defconfigs 2012-03-24 08:18:03 +01:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2012-03-22 20:19:30 -07:00
ia32 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:21:35 -07:00
include/asm x86: merge 32/64-bit versions of 'strncpy_from_user()' and speed it up 2012-04-11 09:41:28 -07:00
kernel Merge branch 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2012-04-07 09:53:33 -07:00
kvm KVM: VMX: vmx_set_cr0 expects kvm->srcu locked 2012-04-05 19:04:09 +03:00
lguest lguest: Make sure interrupt is allocated ok by lguest_setup_irq 2012-01-12 15:44:47 +10:30
lib x86: merge 32/64-bit versions of 'strncpy_from_user()' and speed it up 2012-04-11 09:41:28 -07:00
math-emu x86: Rename trap_no to trap_nr in thread_struct 2012-03-13 06:24:09 +01:00
mm Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:21:35 -07:00
net bpf jit: Let the x86 jit handle negative offsets 2012-04-03 18:01:41 -04:00
oprofile x86: Factor out TIF_IA32 from 32-bit address space 2012-02-20 12:48:46 -08:00
pci Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-03-23 14:02:12 -07:00
platform Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 14:28:26 -07:00
power x86, kvm: Call restore_sched_clock_state() only after %gs is initialized 2012-04-02 13:53:00 +02:00
syscalls Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
tools x86/tools: Add decoded instruction dump mode 2011-12-05 14:53:23 +01:00
um um: Use asm-generic/switch_to.h 2012-04-10 00:13:45 +02:00
vdso Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
video x86: fix up files really needing to include module.h 2011-10-31 19:30:36 -04:00
xen Two fixes for regressions: 2012-04-06 17:54:53 -07:00
.gitignore x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore 2012-01-16 08:21:59 +01:00
Kbuild net: filter: Just In Time compiler for x86-64 2011-04-27 23:05:08 -07:00
Kconfig Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-03-29 18:12:23 -07:00
Kconfig.cpu x86: Tighten dependencies of CPU_SUP_*_32 2012-03-08 10:57:34 +01:00
Kconfig.debug Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-11 19:13:40 -08:00
Makefile x86: Use -mno-avx when available 2012-03-30 10:06:39 -07:00
Makefile.um um: fix linker script generation 2012-04-09 13:59:00 -04:00
Makefile_32.cpu x86, cpu: Move AMD Elan Kconfig under "Processor family" 2011-04-08 13:01:25 -07:00