linux-toradex.git/arch/x86/include/asm/uaccess_64.h, branch v3.9.2 Linux kernel for Apalis and Colibri modules x86, uaccess: Merge prototypes for clear_user/__clear_user 2012-09-21T19:45:26+00:00 H. Peter Anvin hpa@linux.intel.com 2012-09-21T19:43:11+00:00 a052858fabb376b695f2c125633daa6728e0f284 The prototypes for clear_user() and __clear_user() are identical in the 32- and 64-bit headers. No functionality change. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-8-git-send-email-hpa@linux.intel.com 
The prototypes for clear_user() and __clear_user() are identical in
the 32- and 64-bit headers.  No functionality change.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1348256595-29119-8-git-send-email-hpa@linux.intel.com
x86/copy_user_generic: Optimize copy_user_generic with CPU erms feature 2012-06-29T22:33:34+00:00 Fenghua Yu fenghua.yu@intel.com 2012-05-25T01:19:45+00:00 954e482bde20b0e208fd4d34ef26e10afd194600 According to Intel 64 and IA-32 SDM and Optimization Reference Manual, beginning with Ivybridge, REG string operation using MOVSB and STOSB can provide both flexible and high-performance REG string operations in cases like memory copy. Enhancement availability is indicated by CPUID.7.0.EBX[9] (Enhanced REP MOVSB/ STOSB). If CPU erms feature is detected, patch copy_user_generic with enhanced fast string version of copy_user_generic. A few new macros are defined to reduce duplicate code in ALTERNATIVE and ALTERNATIVE_2. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1337908785-14015-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
According to Intel 64 and IA-32 SDM and Optimization Reference Manual, beginning
with Ivybridge, REG string operation using MOVSB and STOSB can provide both
flexible and high-performance REG string operations in cases like memory copy.
Enhancement availability is indicated by CPUID.7.0.EBX[9] (Enhanced REP MOVSB/
STOSB).

If CPU erms feature is detected, patch copy_user_generic with enhanced fast
string version of copy_user_generic.

A few new macros are defined to reduce duplicate code in ALTERNATIVE and
ALTERNATIVE_2.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1337908785-14015-1-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86: use the new generic strnlen_user() function 2012-05-26T18:33:54+00:00 Linus Torvalds torvalds@linux-foundation.org 2012-05-26T18:09:53+00:00 5723aa993d83803157c22327e90cd59e3dcbe879 This throws away the old x86-specific functions in favor of the generic optimized version. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
This throws away the old x86-specific functions in favor of the generic
optimized version.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
x86: merge 32/64-bit versions of 'strncpy_from_user()' and speed it up 2012-04-11T16:41:28+00:00 Linus Torvalds torvalds@linux-foundation.org 2012-04-06T21:32:32+00:00 92ae03f2ef99fbc23bfa9080d6b58f25227bd7ef 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> 
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>
sanitize <linux/prefetch.h> usage 2011-05-20T19:50:29+00:00 Linus Torvalds torvalds@linux-foundation.org 2011-05-20T19:50:29+00:00 268bb0ce3e87872cb9290c322b0d35bce230d88f Commit e66eed651fd1 ("list: remove prefetching from regular list iterators") removed the include of prefetch.h from list.h, which uncovered several cases that had apparently relied on that rather obscure header file dependency. So this fixes things up a bit, using grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]') grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]') to guide us in finding files that either need <linux/prefetch.h> inclusion, or have it despite not needing it. There are more of them around (mostly network drivers), but this gets many core ones. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Commit e66eed651fd1 ("list: remove prefetching from regular list
iterators") removed the include of prefetch.h from list.h, which
uncovered several cases that had apparently relied on that rather
obscure header file dependency.

So this fixes things up a bit, using

   grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]')
   grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]')

to guide us in finding files that either need <linux/prefetch.h>
inclusion, or have it despite not needing it.

There are more of them around (mostly network drivers), but this gets
many core ones.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-28T18:35:09+00:00 Linus Torvalds torvalds@linux-foundation.org 2010-02-28T18:35:09+00:00 a7f16d10b510f9ee3500af7831f2e3094fab3dca * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Mark atomic irq ops raw for 32bit legacy x86: Merge show_regs() x86: Macroise x86 cache descriptors x86-32: clean up rwsem inline asm statements x86: Merge asm/atomic_{32,64}.h x86: Sync asm/atomic_32.h and asm/atomic_64.h x86: Split atomic64_t functions into seperate headers x86-64: Modify memcpy()/memset() alternatives mechanism x86-64: Modify copy_user_generic() alternatives mechanism x86: Lift restriction on the location of FIX_BTMAP_* x86, core: Optimize hweight32() 
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Mark atomic irq ops raw for 32bit legacy
  x86: Merge show_regs()
  x86: Macroise x86 cache descriptors
  x86-32: clean up rwsem inline asm statements
  x86: Merge asm/atomic_{32,64}.h
  x86: Sync asm/atomic_32.h and asm/atomic_64.h
  x86: Split atomic64_t functions into seperate headers
  x86-64: Modify memcpy()/memset() alternatives mechanism
  x86-64: Modify copy_user_generic() alternatives mechanism
  x86: Lift restriction on the location of FIX_BTMAP_*
  x86, core: Optimize hweight32()
x86: copy_from_user() should not return -EFAULT 2010-01-05T21:45:06+00:00 Heiko Carstens heiko.carstens@de.ibm.com 2010-01-05T13:19:11+00:00 409d02ef6d74f5e91f5ea4c587b2ee1375f106fc Callers of copy_from_user() expect it to return the number of bytes it could not copy. In no case it is supposed to return -EFAULT. In case of a detected buffer overflow just return the requested length. In addition one could think of a memset that would clear the size of the target object. [ hpa: code is not in .32 so not needed for -stable ] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <20100105131911.GC5480@osiris.boeblingen.de.ibm.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> 
Callers of copy_from_user() expect it to return the number of bytes
it could not copy. In no case it is supposed to return -EFAULT.

In case of a detected buffer overflow just return the requested
length. In addition one could think of a memset that would clear
the size of the target object.

[ hpa: code is not in .32 so not needed for -stable ]

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20100105131911.GC5480@osiris.boeblingen.de.ibm.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86-64: Modify copy_user_generic() alternatives mechanism 2009-12-30T10:57:31+00:00 Jan Beulich JBeulich@novell.com 2009-12-18T16:12:56+00:00 1b1d9258181bae199dc940f4bd0298126b9a73d9 In order to avoid unnecessary chains of branches, rather than implementing copy_user_generic() as a function consisting of just a single (possibly patched) branch, instead properly deal with patching call instructions in the alternative instructions framework, and move the patching into the callers. As a follow-on, one could also introduce something like __EXPORT_SYMBOL_ALT() to avoid patching call sites in modules. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <4B2BB8180200007800026AE7@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
In order to avoid unnecessary chains of branches, rather than
implementing copy_user_generic() as a function consisting of
just a single (possibly patched) branch, instead properly deal
with patching call instructions in the alternative instructions
framework, and move the patching into the callers.

As a follow-on, one could also introduce something like
__EXPORT_SYMBOL_ALT() to avoid patching call sites in modules.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4B2BB8180200007800026AE7@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86: Add missing might_fault() checks to copy_{to,from}_user() 2009-11-16T15:09:52+00:00 Frederic Weisbecker fweisbec@gmail.com 2009-11-16T14:42:18+00:00 3c93ca00eeeb774c7dd666cc7286a9e90c53e998 On x86-64, copy_[to|from]_user() rely on assembly routines that never call might_fault(), making us missing various lockdep checks. This doesn't apply to __copy_from,to_user() that explicitly handle these calls, neither is it a problem in x86-32 where copy_to,from_user() rely on the "__" prefixed versions that also call might_fault(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1258382538-30979-1-git-send-email-fweisbec@gmail.com> [ v2: fix module export ] Signed-off-by: Ingo Molnar <mingo@elte.hu> 
On x86-64, copy_[to|from]_user() rely on assembly routines that
never call might_fault(), making us missing various lockdep
checks.

This doesn't apply to __copy_from,to_user() that explicitly
handle these calls, neither is it a problem in x86-32 where
copy_to,from_user() rely on the "__" prefixed versions that
also call might_fault().

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1258382538-30979-1-git-send-email-fweisbec@gmail.com>
[ v2: fix module export ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86-64: __copy_from_user_inatomic() adjustments 2009-11-15T08:29:47+00:00 Jan Beulich JBeulich@novell.com 2009-11-13T11:56:24+00:00 14722485830fe6baba738b91d96f06fbd6cf7a18 This v2.6.26 commit: ad2fc2c: x86: fix copy_user on x86 rendered __copy_from_user_inatomic() identical to copy_user_generic(), yet didn't make the former just call the latter from an inline function. Furthermore, this v2.6.19 commit: b885808: [PATCH] Add proper sparse __user casts to __copy_to_user_inatomic converted the return type of __copy_to_user_inatomic() from unsigned long to int, but didn't do the same to __copy_from_user_inatomic(). Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: <v.mayatskih@gmail.com> LKML-Reference: <4AFD5778020000780001F8F4@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
This v2.6.26 commit:

    ad2fc2c: x86: fix copy_user on x86

rendered __copy_from_user_inatomic() identical to
copy_user_generic(), yet didn't make the former just call the
latter from an inline function.

Furthermore, this v2.6.19 commit:

    b885808: [PATCH] Add proper sparse __user casts to __copy_to_user_inatomic

converted the return type of __copy_to_user_inatomic() from
unsigned long to int, but didn't do the same to
__copy_from_user_inatomic().

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: <v.mayatskih@gmail.com>
LKML-Reference: <4AFD5778020000780001F8F4@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>