Hi Jürgen,
Would you be able to explain the notes
/* In an error exception handler the user space could be uncached. */
in the patch ported from v2.6 below?
Fredrik
diff --git a/arch/mips/include/asm/ftrace.h b/arch/mips/include/asm/ftrace.h
index b463f2aa5a61..79390b194e6d 100644
--- a/arch/mips/include/asm/ftrace.h
+++ b/arch/mips/include/asm/ftrace.h
@@ -19,9 +19,12 @@
extern void _mcount(void);
#define mcount _mcount
+#ifdef CONFIG_CPU_R5900
#define safe_load(load, src, dst, error) \
do { \
asm volatile ( \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
"1: " load " %[tmp_dst], 0(%[tmp_src])\n" \
" li %[tmp_err], 0\n" \
"2: .insn\n" \
@@ -40,7 +43,55 @@ do { \
: "memory" \
); \
} while (0)
+#else
+#define safe_load(load, src, dst, error) \
+do { \
+ asm volatile ( \
+ "1: " load " %[" STR(dst) "], 0(%[" STR(src) "])\n"\
+ " li %[" STR(error) "], 0\n" \
+ "2:\n" \
+ \
+ ".section .fixup, \"ax\"\n" \
+ "3: li %[" STR(error) "], 1\n" \
+ " j 2b\n" \
+ ".previous\n" \
+ \
+ ".section\t__ex_table,\"a\"\n\t" \
+ STR(PTR) "\t1b, 3b\n\t" \
+ ".previous\n" \
+ \
+ : [dst] "=&r" (dst), [error] "=r" (error)\
+ : [src] "r" (src) \
+ : "memory" \
+ ); \
+} while (0)
+#endif
+#ifdef CONFIG_CPU_R5900
+#define safe_store(store, src, dst, error) \
+do { \
+ asm volatile ( \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
+ "1: " store " %[" STR(src) "], 0(%[" STR(dst) "])\n"\
+ " li %[" STR(error) "], 0\n" \
+ "2:\n" \
+ \
+ ".section .fixup, \"ax\"\n" \
+ "3: li %[" STR(error) "], 1\n" \
+ " j 2b\n" \
+ ".previous\n" \
+ \
+ ".section\t__ex_table,\"a\"\n\t"\
+ STR(PTR) "\t1b, 3b\n\t" \
+ ".previous\n" \
+ \
+ : [error] "=r" (error) \
+ : [dst] "r" (dst), [src] "r" (src)\
+ : "memory" \
+ ); \
+} while (0)
+#else
#define safe_store(store, src, dst, error) \
do { \
asm volatile ( \
@@ -62,6 +113,7 @@ do { \
: "memory" \
); \
} while (0)
+#endif
#define safe_load_code(dst, src, error) \
safe_load(STR(lw), src, dst, error)
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index b71306947290..a4eecafc524b 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -315,11 +315,14 @@ do { \
__gu_err; \
})
+#ifdef CONFIG_CPU_R5900
#define __get_data_asm(val, insn, addr) \
{ \
long __gu_tmp; \
\
__asm__ __volatile__( \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
"1: "insn("%1", "%3")" \n" \
"2: \n" \
" .insn \n" \
@@ -336,10 +339,32 @@ do { \
\
(val) = (__typeof__(*(addr))) __gu_tmp; \
}
+#else
+#define __get_data_asm(val, insn, addr) \
+{ \
+ long __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: "insn("%1", "%3")" \n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " "__UA_ADDR "\t1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=r" (__gu_tmp) \
+ : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
+ \
+ (val) = (__typeof__(*(addr))) __gu_tmp; \
+}
+#endif
/*
* Get a long long 64 using 32 bit registers.
*/
+#ifdef CONFIG_CPU_R5900
#define __get_data_asm_ll32(val, insn, addr) \
{ \
union { \
@@ -348,7 +373,11 @@ do { \
} __gu_tmp; \
\
__asm__ __volatile__( \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
"1: " insn("%1", "(%3)")" \n" \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
"2: " insn("%D1", "4(%3)")" \n" \
"3: \n" \
" .insn \n" \
@@ -367,6 +396,33 @@ do { \
\
(val) = __gu_tmp.t; \
}
+#else
+#define __get_data_asm_ll32(val, insn, addr) \
+{ \
+ union { \
+ unsigned long long l; \
+ __typeof__(*(addr)) t; \
+ } __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: " insn("%1", "(%3)")" \n" \
+ "2: " insn("%D1", "4(%3)")" \n" \
+ "3: .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " move %1, $0 \n" \
+ " move %D1, $0 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
+ : "0" (0), "r" (addr), "i" (-EFAULT)); \
+ \
+ (val) = __gu_tmp.t; \
+}
+#endif
#ifndef CONFIG_EVA
#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
@@ -456,6 +512,38 @@ do { \
__pu_err; \
})
+#define __put_user_check_atomic(x, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ int __pu_err = -EFAULT; \
+ \
+ if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
+ __put_kernel_common(ptr, size); \
+ } \
+ __pu_err; \
+})
+
+#ifdef CONFIG_CPU_R5900
+#define __put_data_asm(insn, ptr) \
+{ \
+ __asm__ __volatile__( \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
+ "1: "insn("%z2", "%3")" # __put_data_asm \n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__pu_err) \
+ : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
+ "i" (-EFAULT)); \
+}
+#else
#define __put_data_asm(insn, ptr) \
{ \
__asm__ __volatile__( \
@@ -473,7 +561,32 @@ do { \
: "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
"i" (-EFAULT)); \
}
+#endif
+#ifdef CONFIG_CPU_R5900
+#define __put_data_asm_ll32(insn, ptr) \
+{ \
+ __asm__ __volatile__( \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
+ "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
+ /* In an error exception handler the user space could be uncached. */ \
+ "sync.l \n" \
+ "2: "insn("%D2", "4(%3)")" \n" \
+ "3: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous" \
+ : "=r" (__pu_err) \
+ : "0" (0), "r" (__pu_val), "r" (ptr), \
+ "i" (-EFAULT)); \
+}
+#else
#define __put_data_asm_ll32(insn, ptr) \
{ \
__asm__ __volatile__( \
@@ -493,6 +606,7 @@ do { \
: "0" (0), "r" (__pu_val), "r" (ptr), \
"i" (-EFAULT)); \
}
+#endif
extern void __put_user_unknown(void);
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index b280a3d775a1..625b74de1ce4 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -488,10 +488,15 @@ do { \
#else /* __BIG_ENDIAN */
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* FIXME: Is ".set push\n" etc. needed? */
+ /* In an error exception handler the user space could be uncached. */
#define _LoadHW(addr, value, res, type) \
do { \
__asm__ __volatile__ (".set\tnoat\n" \
+ "sync.l\n\t" \
"1:\t"type##_lb("%0", "1(%2)")"\n" \
+ "sync.l\n\t" \
"2:\t"type##_lbu("$1", "0(%2)")"\n\t"\
"sll\t%0, 0x8\n\t" \
"or\t%0, $1\n\t" \
@@ -511,10 +516,14 @@ do { \
} while(0)
#ifndef CONFIG_CPU_MIPSR6
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* In an error exception handler the user space could be uncached. */
#define _LoadW(addr, value, res, type) \
do { \
__asm__ __volatile__ ( \
+ "sync.l\n\t" \
"1:\t"type##_lwl("%0", "3(%2)")"\n" \
+ "sync.l\n\t" \
"2:\t"type##_lwr("%0", "(%2)")"\n\t"\
"li\t%1, 0\n" \
"3:\n\t" \
@@ -569,11 +578,15 @@ do { \
#endif /* CONFIG_CPU_MIPSR6 */
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* In an error exception handler the user space could be uncached. */
#define _LoadHWU(addr, value, res, type) \
do { \
__asm__ __volatile__ ( \
".set\tnoat\n" \
+ "sync.l\n\t" \
"1:\t"type##_lbu("%0", "1(%2)")"\n" \
+ "sync.l\n\t" \
"2:\t"type##_lbu("$1", "0(%2)")"\n\t"\
"sll\t%0, 0x8\n\t" \
"or\t%0, $1\n\t" \
@@ -594,10 +607,14 @@ do { \
} while(0)
#ifndef CONFIG_CPU_MIPSR6
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* In an error exception handler the user space could be uncached. */
#define _LoadWU(addr, value, res, type) \
do { \
__asm__ __volatile__ ( \
+ "sync.l\n\t" \
"1:\t"type##_lwl("%0", "3(%2)")"\n" \
+ "sync.l\n\t" \
"2:\t"type##_lwr("%0", "(%2)")"\n\t"\
"dsll\t%0, %0, 32\n\t" \
"dsrl\t%0, %0, 32\n\t" \
@@ -616,10 +633,14 @@ do { \
: "r" (addr), "i" (-EFAULT)); \
} while(0)
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* In an error exception handler the user space could be uncached. */
#define _LoadDW(addr, value, res) \
do { \
__asm__ __volatile__ ( \
+ "sync.l\n\t" \
"1:\tldl\t%0, 7(%2)\n" \
+ "sync.l\n\t" \
"2:\tldr\t%0, (%2)\n\t" \
"li\t%1, 0\n" \
"3:\n\t" \
@@ -721,11 +742,15 @@ do { \
} while(0)
#endif /* CONFIG_CPU_MIPSR6 */
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* In an error exception handler the user space could be uncached. */
#define _StoreHW(addr, value, res, type) \
do { \
__asm__ __volatile__ ( \
".set\tnoat\n" \
+ "sync.l\n\t" \
"1:\t"type##_sb("%1", "0(%2)")"\n" \
+ "sync.l\n\t" \
"srl\t$1,%1, 0x8\n" \
"2:\t"type##_sb("$1", "1(%2)")"\n" \
".set\tat\n\t" \
@@ -745,10 +770,13 @@ do { \
} while(0)
#ifndef CONFIG_CPU_MIPSR6
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
#define _StoreW(addr, value, res, type) \
do { \
__asm__ __volatile__ ( \
+ "sync.l\n\t" \
"1:\t"type##_swl("%1", "3(%2)")"\n" \
+ "sync.l\n\t" \
"2:\t"type##_swr("%1", "(%2)")"\n\t"\
"li\t%0, 0\n" \
"3:\n\t" \
@@ -765,10 +793,14 @@ do { \
: "r" (value), "r" (addr), "i" (-EFAULT)); \
} while(0)
+ /* FIXME: Use #ifdef CONFIG_CPU_R5900 */
+ /* In an error exception handler the user space could be uncached. */
#define _StoreDW(addr, value, res) \
do { \
__asm__ __volatile__ ( \
+ "sync.l\n\t" \
"1:\tsdl\t%1, 7(%2)\n" \
+ "sync.l\n\t" \
"2:\tsdr\t%1, (%2)\n\t" \
"li\t%0, 0\n" \
"3:\n\t" \
diff --git a/arch/mips/lib/csum_partial.S b/arch/mips/lib/csum_partial.S
index 2ff84f4b1717..36e48682e1e1 100644
--- a/arch/mips/lib/csum_partial.S
+++ b/arch/mips/lib/csum_partial.S
@@ -357,7 +357,10 @@ EXPORT_SYMBOL(csum_partial)
* addr : Address
* handler : Exception handler
*/
+/* FIXME: #ifdef CONFIG_CPU_R5900 */
#define EXC(insn, type, reg, addr, handler) \
+ /* In an error exception handler the user space could be uncached. */ \
+ sync.l; \
.if \mode == LEGACY_MODE; \
9: insn reg, addr; \
.section __ex_table,"a"; \
diff --git a/arch/mips/lib/memset.S b/arch/mips/lib/memset.S
index 489bc9cffcbd..b37731f53f46 100644
--- a/arch/mips/lib/memset.S
+++ b/arch/mips/lib/memset.S
@@ -46,6 +46,11 @@
#define ___BUILD_EVA_INSN(insn, reg, addr) __EVAFY(insn, reg, addr)
#define EX(insn,reg,addr,handler) \
+ /* In an error exception handler the user space could be uncached. */ \
+ .set push; \
+ .set noreorder; \
+ sync.l; \
+ .set pop; \
.if \mode == LEGACY_MODE; \
9: insn reg, addr; \
.else; \
@@ -171,6 +176,19 @@
#ifdef CONFIG_CPU_MICROMIPS
LONG_SRL t7, t0, 1
#endif
+#ifdef CONFIG_CPU_R5900
+ /* Each instruction has a leading sync.l */
+#if LONGSIZE == 4
+ .set noat
+ /* 2 instructions for 4 Byte. */
+ LONG_SLL AT, t0, 1
+ PTR_SUBU t1, AT
+ .set at
+#else
+ /* Verify memset for R5900 with 64 bit. 2 instructions for 8 Byte. */
+ PTR_SUBU t1, t0
+#endif
+#else
#if LONGSIZE == 4
PTR_SUBU t1, FILLPTRG
#else
@@ -179,6 +197,7 @@
PTR_SUBU t1, AT
.set at
#endif
+#endif /* CONFIG_CPU_R5900 */
jr t1
PTR_ADDU a0, t0 /* dest ptr */
diff --git a/arch/mips/lib/strncpy_user.S b/arch/mips/lib/strncpy_user.S
index 44cc346fd400..0cf9a6660130 100644
--- a/arch/mips/lib/strncpy_user.S
+++ b/arch/mips/lib/strncpy_user.S
@@ -13,6 +13,8 @@
#include <asm/regdef.h>
#define EX(insn,reg,addr,handler) \
+ /* In an error exception handler the user space could be uncached. */ \
+ sync.l; \
9: insn reg, addr; \
.section __ex_table,"a"; \
PTR 9b, handler; \
diff --git a/arch/mips/lib/strnlen_user.S b/arch/mips/lib/strnlen_user.S
index 474979641a8d..55f7e069a960 100644
--- a/arch/mips/lib/strnlen_user.S
+++ b/arch/mips/lib/strnlen_user.S
@@ -12,6 +12,8 @@
#include <asm/regdef.h>
#define EX(insn,reg,addr,handler) \
+ /* In an error exception handler the user space could be uncached. */ \
+ sync.l; \
9: insn reg, addr; \
.section __ex_table,"a"; \
PTR 9b, handler; \
