lkml.org 
[lkml]   [2009]   [Sep]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] MN10300: Fix kernel build failures when using gcc-4.x
Date
From: Mark Salter <msalter@redhat.com>

Fix some build failures when using gcc-4.x for MN10300.

Firstly, __get_user() fails to build because the pointer points to a const and
__gu_val ends up being read-only:

In file included from include/linux/mempolicy.h:62,
from init/main.c:50:
include/linux/pagemap.h: In function 'fault_in_pages_readable':
include/linux/pagemap.h:394: error: read-only variable '__gu_val' used as 'asm' output
include/linux/pagemap.h:394: error: read-only variable '__gu_val' used as 'asm' output
include/linux/pagemap.h:394: error: read-only variable '__gu_val' used as 'asm' output
include/linux/pagemap.h:400: error: read-only variable '__gu_val' used as 'asm' output
include/linux/pagemap.h:400: error: read-only variable '__gu_val' used as 'asm' output
include/linux/pagemap.h:400: error: read-only variable '__gu_val' used as 'asm' output
make[1]: *** [init/main.o] Error 1

Secondly, gcc-4 doesn't allow casts of lvalues:

UPD include/linux/compile.h
arch/mn10300/kernel/rtc.c: In function 'calibrate_clock':
arch/mn10300/kernel/rtc.c:170: error: lvalue required as left operand of assignment
arch/mn10300/kernel/rtc.c:172: error: lvalue required as left operand of assignment
make[1]: *** [arch/mn10300/kernel/rtc.o] Error 1

These are seen with gcc 4.2.1.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
---

arch/mn10300/include/asm/uaccess.h | 73 +++++++++++++-----------
arch/mn10300/unit-asb2303/include/unit/clock.h | 6 +-
arch/mn10300/unit-asb2305/include/unit/clock.h | 6 +-
3 files changed, 45 insertions(+), 40 deletions(-)


diff --git a/arch/mn10300/include/asm/uaccess.h b/arch/mn10300/include/asm/uaccess.h
index 8a3a4dd..167e10f 100644
--- a/arch/mn10300/include/asm/uaccess.h
+++ b/arch/mn10300/include/asm/uaccess.h
@@ -129,42 +129,47 @@ extern int fixup_exception(struct pt_regs *regs);
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct *)(x))

-#define __get_user_nocheck(x, ptr, size) \
-({ \
- __typeof(*(ptr)) __gu_val; \
- unsigned long __gu_addr; \
- int __gu_err; \
- __gu_addr = (unsigned long) (ptr); \
- switch (size) { \
- case 1: __get_user_asm("bu"); break; \
- case 2: __get_user_asm("hu"); break; \
- case 4: __get_user_asm("" ); break; \
- default: __get_user_unknown(); break; \
- } \
- x = (__typeof__(*(ptr))) __gu_val; \
- __gu_err; \
+#define __get_user_nocheck(x, ptr, size) \
+({ \
+ unsigned long __gu_addr; \
+ int __gu_err; \
+ __gu_addr = (unsigned long) (ptr); \
+ switch (size) { \
+ case 1: { \
+ unsigned char __gu_val; \
+ __get_user_asm("bu"); \
+ (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \
+ break; \
+ } \
+ case 2: { \
+ unsigned short __gu_val; \
+ __get_user_asm("hu"); \
+ (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \
+ break; \
+ } \
+ case 4: { \
+ unsigned int __gu_val; \
+ __get_user_asm(""); \
+ (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \
+ break; \
+ } \
+ default: \
+ __get_user_unknown(); \
+ break; \
+ } \
+ __gu_err; \
})

-#define __get_user_check(x, ptr, size) \
-({ \
- __typeof__(*(ptr)) __gu_val; \
- unsigned long __gu_addr; \
- int __gu_err; \
- __gu_addr = (unsigned long) (ptr); \
- if (likely(__access_ok(__gu_addr,size))) { \
- switch (size) { \
- case 1: __get_user_asm("bu"); break; \
- case 2: __get_user_asm("hu"); break; \
- case 4: __get_user_asm("" ); break; \
- default: __get_user_unknown(); break; \
- } \
- } \
- else { \
- __gu_err = -EFAULT; \
- __gu_val = 0; \
- } \
- x = (__typeof__(*(ptr))) __gu_val; \
- __gu_err; \
+#define __get_user_check(x, ptr, size) \
+({ \
+ int _e; \
+ if (likely(__access_ok((unsigned long) (ptr), (size)))) \
+ _e = __get_user_nocheck((x), (ptr), (size)); \
+ else { \
+ _e = -EFAULT; \
+ (x) = (__typeof__(x))0; \
+ } \
+ _e; \
})

#define __get_user_asm(INSN) \
diff --git a/arch/mn10300/unit-asb2303/include/unit/clock.h b/arch/mn10300/unit-asb2303/include/unit/clock.h
index 8b450e9..2a0bf79 100644
--- a/arch/mn10300/unit-asb2303/include/unit/clock.h
+++ b/arch/mn10300/unit-asb2303/include/unit/clock.h
@@ -20,9 +20,9 @@ extern unsigned long mn10300_ioclk; /* IOCLK (crystal speed) in HZ */
extern unsigned long mn10300_iobclk;
extern unsigned long mn10300_tsc_per_HZ;

-#define MN10300_IOCLK ((unsigned long)mn10300_ioclk)
+#define MN10300_IOCLK mn10300_ioclk
/* If this processors has a another clock, uncomment the below. */
-/* #define MN10300_IOBCLK ((unsigned long)mn10300_iobclk) */
+/* #define MN10300_IOBCLK mn10300_iobclk */

#else /* !CONFIG_MN10300_RTC */

@@ -35,7 +35,7 @@ extern unsigned long mn10300_tsc_per_HZ;
#define MN10300_TSCCLK MN10300_IOCLK

#ifdef CONFIG_MN10300_RTC
-#define MN10300_TSC_PER_HZ ((unsigned long)mn10300_tsc_per_HZ)
+#define MN10300_TSC_PER_HZ mn10300_tsc_per_HZ
#else /* !CONFIG_MN10300_RTC */
#define MN10300_TSC_PER_HZ (MN10300_TSCCLK/HZ)
#endif /* !CONFIG_MN10300_RTC */
diff --git a/arch/mn10300/unit-asb2305/include/unit/clock.h b/arch/mn10300/unit-asb2305/include/unit/clock.h
index 7d51484..67be3f2 100644
--- a/arch/mn10300/unit-asb2305/include/unit/clock.h
+++ b/arch/mn10300/unit-asb2305/include/unit/clock.h
@@ -20,9 +20,9 @@ extern unsigned long mn10300_ioclk; /* IOCLK (crystal speed) in HZ */
extern unsigned long mn10300_iobclk;
extern unsigned long mn10300_tsc_per_HZ;

-#define MN10300_IOCLK ((unsigned long)mn10300_ioclk)
+#define MN10300_IOCLK mn10300_ioclk
/* If this processors has a another clock, uncomment the below. */
-/* #define MN10300_IOBCLK ((unsigned long)mn10300_iobclk) */
+/* #define MN10300_IOBCLK mn10300_iobclk */

#else /* !CONFIG_MN10300_RTC */

@@ -35,7 +35,7 @@ extern unsigned long mn10300_tsc_per_HZ;
#define MN10300_TSCCLK MN10300_IOCLK

#ifdef CONFIG_MN10300_RTC
-#define MN10300_TSC_PER_HZ ((unsigned long)mn10300_tsc_per_HZ)
+#define MN10300_TSC_PER_HZ mn10300_tsc_per_HZ
#else /* !CONFIG_MN10300_RTC */
#define MN10300_TSC_PER_HZ (MN10300_TSCCLK/HZ)
#endif /* !CONFIG_MN10300_RTC */


\
 
 \ /
  Last update: 2009-09-30 11:59    [W:0.049 / U:0.272 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site