2012-05-25 06:24:18

by Jonas Bonn

[permalink] [raw]
Subject: [PATCH 1/1] openrisc: use generic strncpy_from_user


As per commits 2922585b93294d47172a765115e0dbc1bfe1be19
("lib: Sparc's strncpy_from_user is generic enough, move under lib/"),
92ae03f2ef99fbc23bfa9080d6b58f25227bd7ef ("x86: merge 32/64-bit versions
of 'strncpy_from_user()' and speed it up"), and corresponding
discussion on linux-arch.

Signed-off-by: Jonas Bonn <[email protected]>
---

Hi Linus,

Here's a single patch update to the OpenRISC arch to use the new
strncpy_from_user implementation. Hope it's ok to send it as a
single patch and not as a pull request; let me know otherwise.

Thanks,
Jonas

arch/openrisc/Kconfig | 1 +
arch/openrisc/include/asm/uaccess.h | 10 ++-----
arch/openrisc/lib/string.S | 52 -----------------------------------
3 files changed, 4 insertions(+), 59 deletions(-)

diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index da4ccd1..ee4d124 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -19,6 +19,7 @@ config OPENRISC
select GENERIC_CPU_DEVICES
select GENERIC_ATOMIC64
select GENERIC_CLOCKEVENTS
+ select GENERIC_STRNCPY_FROM_USER

config MMU
def_bool y
diff --git a/arch/openrisc/include/asm/uaccess.h b/arch/openrisc/include/asm/uaccess.h
index f5abaa0..04b93de 100644
--- a/arch/openrisc/include/asm/uaccess.h
+++ b/arch/openrisc/include/asm/uaccess.h
@@ -313,14 +313,10 @@ clear_user(void *addr, unsigned long size)
return size;
}

-extern int __strncpy_from_user(char *dst, const char *src, long count);
+#define user_addr_max() \
+ (segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL)

-static inline long strncpy_from_user(char *dst, const char *src, long count)
-{
- if (access_ok(VERIFY_READ, src, 1))
- return __strncpy_from_user(dst, src, count);
- return -EFAULT;
-}
+extern long strncpy_from_user(char *dest, const char __user *src, long count);

/*
* Return the size of a string (including the ending 0)
diff --git a/arch/openrisc/lib/string.S b/arch/openrisc/lib/string.S
index 465f04b..8ceb11e 100644
--- a/arch/openrisc/lib/string.S
+++ b/arch/openrisc/lib/string.S
@@ -104,58 +104,6 @@ __clear_user:
.long 9b, 99b // write fault
.previous

-/*
- * long strncpy_from_user(char *dst, const char *src, long count)
- *
- *
- */
- .global __strncpy_from_user
-__strncpy_from_user:
- l.addi r1,r1,-16
- l.sw 0(r1),r6
- l.sw 4(r1),r5
- l.sw 8(r1),r4
- l.sw 12(r1),r3
-
- l.addi r11,r5,0
-2: l.sfeq r5,r0
- l.bf 1f
- l.addi r5,r5,-1
-8: l.lbz r6,0(r4)
- l.sfeq r6,r0
- l.bf 1f
-9: l.sb 0(r3),r6
- l.addi r3,r3,1
- l.j 2b
- l.addi r4,r4,1
-1:
- l.lwz r6,0(r1)
- l.addi r5,r5,1
- l.sub r11,r11,r5 // r11 holds the return value
-
- l.lwz r6,0(r1)
- l.lwz r5,4(r1)
- l.lwz r4,8(r1)
- l.lwz r3,12(r1)
- l.jr r9
- l.addi r1,r1,16
-
- .section .fixup, "ax"
-99:
- l.movhi r11,hi(-EFAULT)
- l.ori r11,r11,lo(-EFAULT)
-
- l.lwz r6,0(r1)
- l.lwz r5,4(r1)
- l.lwz r4,8(r1)
- l.lwz r3,12(r1)
- l.jr r9
- l.addi r1,r1,16
- .previous
-
- .section __ex_table, "a"
- .long 8b, 99b // read fault
- .previous

/*
* extern int __strnlen_user(const char *str, long len, unsigned long top);
--
1.7.0.4