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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2006-06-21 20:38:17 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2006-06-28 17:59:46 +0100
commit9641c7cc5a7f6d5c9dc9b43eea4e5f8c3c08c94e (patch)
tree5ff57feabe0538d58404ec4918b0d94d75f69846 /arch
parent002547b4f86c27bfac5bae344b723d250857be6b (diff)
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[ARM] nommu: uaccess tweaks
MMUless systems have only one address space for all threads, so both the usual access_ok() checks, and the exception handling do not make much sense. Hence, discard the fixup and exception tables at link time, use memcpy/memset for the user copy/clearing functions, and define the permission check macros to be constants. Some of this patch was derived from the equivalent patch by Hyok S. Choi. Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/kernel/armksyms.c7
-rw-r--r--arch/arm/kernel/vmlinux.lds.S8
-rw-r--r--arch/arm/lib/Makefile13
3 files changed, 21 insertions, 7 deletions
diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c
index f8bb7abd3e9b..da69e660574b 100644
--- a/arch/arm/kernel/armksyms.c
+++ b/arch/arm/kernel/armksyms.c
@@ -109,11 +109,13 @@ EXPORT_SYMBOL(memchr);
EXPORT_SYMBOL(__memzero);
/* user mem (segment) */
+EXPORT_SYMBOL(__strnlen_user);
+EXPORT_SYMBOL(__strncpy_from_user);
+
+#ifdef CONFIG_MMU
EXPORT_SYMBOL(__copy_from_user);
EXPORT_SYMBOL(__copy_to_user);
EXPORT_SYMBOL(__clear_user);
-EXPORT_SYMBOL(__strnlen_user);
-EXPORT_SYMBOL(__strncpy_from_user);
EXPORT_SYMBOL(__get_user_1);
EXPORT_SYMBOL(__get_user_2);
@@ -123,6 +125,7 @@ EXPORT_SYMBOL(__put_user_1);
EXPORT_SYMBOL(__put_user_2);
EXPORT_SYMBOL(__put_user_4);
EXPORT_SYMBOL(__put_user_8);
+#endif
/* crypto hash */
EXPORT_SYMBOL(sha_transform);
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 2b254e88595c..2df9688a7028 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -80,6 +80,10 @@ SECTIONS
*(.exit.text)
*(.exit.data)
*(.exitcall.exit)
+#ifndef CONFIG_MMU
+ *(.fixup)
+ *(__ex_table)
+#endif
}
.text : { /* Real text segment */
@@ -87,7 +91,9 @@ SECTIONS
*(.text)
SCHED_TEXT
LOCK_TEXT
+#ifdef CONFIG_MMU
*(.fixup)
+#endif
*(.gnu.warning)
*(.rodata)
*(.rodata.*)
@@ -142,7 +148,9 @@ SECTIONS
*/
. = ALIGN(32);
__start___ex_table = .;
+#ifdef CONFIG_MMU
*(__ex_table)
+#endif
__stop___ex_table = .;
/*
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 7b726b627ea5..30351cd4560d 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -6,28 +6,31 @@
lib-y := backtrace.o changebit.o csumipv6.o csumpartial.o \
csumpartialcopy.o csumpartialcopyuser.o clearbit.o \
- copy_page.o delay.o findbit.o memchr.o memcpy.o \
+ delay.o findbit.o memchr.o memcpy.o \
memmove.o memset.o memzero.o setbit.o \
strncpy_from_user.o strnlen_user.o \
strchr.o strrchr.o \
testchangebit.o testclearbit.o testsetbit.o \
- getuser.o putuser.o clear_user.o \
ashldi3.o ashrdi3.o lshrdi3.o muldi3.o \
ucmpdi2.o lib1funcs.o div64.o sha1.o \
io-readsb.o io-writesb.o io-readsl.o io-writesl.o
+mmu-y := clear_user.o copy_page.o getuser.o putuser.o
+
# the code in uaccess.S is not preemption safe and
# probably faster on ARMv3 only
ifeq ($(CONFIG_PREEMPT),y)
- lib-y += copy_from_user.o copy_to_user.o
+ mmu-y += copy_from_user.o copy_to_user.o
else
ifneq ($(CONFIG_CPU_32v3),y)
- lib-y += copy_from_user.o copy_to_user.o
+ mmu-y += copy_from_user.o copy_to_user.o
else
- lib-y += uaccess.o
+ mmu-y += uaccess.o
endif
endif
+lib-$(CONFIG_MMU) += $(mmu-y)
+
ifeq ($(CONFIG_CPU_32v3),y)
lib-y += io-readsw-armv3.o io-writesw-armv3.o
else
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