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kernel-ark/arch/sparc/lib/GENcopy_to_user.S

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[SPARC64]: Do not assume sun4v chips have load-twin/store-init support. Check the cpu type in the OBP device tree before committing to using the optimized Niagara memcpy and memset implementation. If we don't recognize the cpu type, use a completely generic version. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-09 00:11:39 +00:00
/* GENcopy_to_user.S: Generic sparc64 copy to userspace.
*
* Copyright (C) 2007 David S. Miller (davem@davemloft.net)
*/
#define EX_ST(x) \
98: x; \
.section __ex_table,"a";\
.align 4; \
sparc64: Kill .fixup section bloat. This is an implementation of a suggestion made by Chris Torek: -------------------- Something else I noticed in passing: the EX and EX_LD/EX_ST macros scattered throughout the various .S files make a fair bit of .fixup code, all of which does the same thing. At the cost of one symbol in copy_in_user.S, you could just have one common two-instruction retl-and-mov-1 fixup that they all share. -------------------- The following is with a defconfig build: text data bss dec hex filename 3972767 344024 584449 4901240 4ac978 vmlinux.orig 3968887 344024 584449 4897360 4aba50 vmlinux Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-09 06:00:55 +00:00
.word 98b, __retl_one; \
[SPARC64]: Do not assume sun4v chips have load-twin/store-init support. Check the cpu type in the OBP device tree before committing to using the optimized Niagara memcpy and memset implementation. If we don't recognize the cpu type, use a completely generic version. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-09 00:11:39 +00:00
.text; \
.align 4;
#ifndef ASI_AIUS
#define ASI_AIUS 0x11
#endif
#define FUNC_NAME GENcopy_to_user
#define STORE(type,src,addr) type##a src, [addr] ASI_AIUS
#define EX_RETVAL(x) 0
#ifdef __KERNEL__
/* Writing to %asi is _expensive_ so we hardcode it.
* Reading %asi to check for KERNEL_DS is comparatively
* cheap.
*/
#define PREAMBLE \
rd %asi, %g1; \
cmp %g1, ASI_AIUS; \
sparc64: Fix probe_kernel_{read,write}(). This is based upon a report from Chris Torek and his initial patch. From Chris's report: -------------------- This came up in testing kgdb, using the built-in tests -- turn on CONFIG_KGDB_TESTS, then echo V1 > /sys/module/kgdbts/parameters/kgdbts -- but it would affect using kgdb if you were debugging and looking at bad pointers. -------------------- When we get a copy_{from,to}_user() request and the %asi is set to something other than ASI_AIUS (which is userspace) then we branch off to a routine called memcpy_user_stub(). It just does a straight memcpy since we are copying from kernel to kernel in this case. The logic was that since source and destination are both kernel pointers we don't need to have exception checks. But for what probe_kernel_{read,write}() is trying to do, we have to have the checks, otherwise things like kgdb bad kernel pointer accesses don't do the right thing. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-09 06:32:31 +00:00
bne,pn %icc, ___copy_in_user; \
[SPARC64]: Do not assume sun4v chips have load-twin/store-init support. Check the cpu type in the OBP device tree before committing to using the optimized Niagara memcpy and memset implementation. If we don't recognize the cpu type, use a completely generic version. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-09 00:11:39 +00:00
nop
#endif
#include "GENmemcpy.S"
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