sh: switch to generic strncpy_from_user().

This kills off the special sh32/64 versions and adopts the generic
version. It should be possible to optimize this for SH-4A unaligned
loads, but this is a corner case that can be supported incrementally.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

6 files changed, 5 insertions, 114 deletions

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 99bcd0ee838d..cbffc26c0434 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -32,6 +32,7 @@ config SUPERH
         select GENERIC_SMP_IDLE_THREAD
         select GENERIC_CLOCKEVENTS
         select GENERIC_CMOS_UPDATE if SH_SH03 || SH_DREAMCAST
+        select GENERIC_STRNCPY_FROM_USER
         help
           The SuperH is a RISC processor targeted for use in embedded systems
           and consumer electronics; it was also used in the Sega Dreamcast
diff --git a/arch/sh/include/asm/uaccess.h b/arch/sh/include/asm/uaccess.h
index 050f221fa898..3df7eee9c155 100644
--- a/arch/sh/include/asm/uaccess.h
+++ b/arch/sh/include/asm/uaccess.h
@@ -25,6 +25,8 @@
         (__chk_user_ptr(addr),          \
          __access_ok((unsigned long __force)(addr), (size)))
 
+#define user_addr_max() (current_thread_info()->addr_limit.seg)
+
 /*
  * Uh, these should become the main single-value transfer routines ...
  * They automatically use the right size if we just have the right
@@ -100,6 +102,8 @@ struct __large_struct { unsigned long buf[100]; };
 # include "uaccess_64.h"
 #endif
 
+extern long strncpy_from_user(char *dest, const char __user *src, long count);
+
 /* Generic arbitrary sized copy.  */
 /* Return the number of bytes NOT copied */
 __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
@@ -137,37 +141,6 @@ __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
         __cl_size;                                                      \
 })
 
-/**
- * strncpy_from_user: - Copy a NUL terminated string from userspace.
- * @dst:   Destination address, in kernel space.  This buffer must be at
- *         least @count bytes long.
- * @src:   Source address, in user space.
- * @count: Maximum number of bytes to copy, including the trailing NUL.
- *
- * Copies a NUL-terminated string from userspace to kernel space.
- *
- * On success, returns the length of the string (not including the trailing
- * NUL).
- *
- * If access to userspace fails, returns -EFAULT (some data may have been
- * copied).
- *
- * If @count is smaller than the length of the string, copies @count bytes
- * and returns @count.
- */
-#define strncpy_from_user(dest,src,count)                               \
-({                                                                      \
-        unsigned long __sfu_src = (unsigned long)(src);                 \
-        int __sfu_count = (int)(count);                                 \
-        long __sfu_res = -EFAULT;                                       \
-                                                                        \
-        if (__access_ok(__sfu_src, __sfu_count))                        \
-                __sfu_res = __strncpy_from_user((unsigned long)(dest),  \
-                                __sfu_src, __sfu_count);                \
-                                                                        \
-        __sfu_res;                                                      \
-})
-
 static inline unsigned long
 copy_from_user(void *to, const void __user *from, unsigned long n)
 {
diff --git a/arch/sh/include/asm/uaccess_32.h b/arch/sh/include/asm/uaccess_32.h
index ae0d24f6653f..ef44d05bb631 100644
--- a/arch/sh/include/asm/uaccess_32.h
+++ b/arch/sh/include/asm/uaccess_32.h
@@ -170,45 +170,6 @@ __asm__ __volatile__( \
 
 extern void __put_user_unknown(void);
 
-static inline int
-__strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __count)
-{
-        __kernel_size_t res;
-        unsigned long __dummy, _d, _s, _c;
-
-        __asm__ __volatile__(
-                "9:\n"
-                "mov.b  @%2+, %1\n\t"
-                "cmp/eq #0, %1\n\t"
-                "bt/s   2f\n"
-                "1:\n"
-                "mov.b  %1, @%3\n\t"
-                "dt     %4\n\t"
-                "bf/s   9b\n\t"
-                " add   #1, %3\n\t"
-                "2:\n\t"
-                "sub    %4, %0\n"
-                "3:\n"
-                ".section .fixup,\"ax\"\n"
-                "4:\n\t"
-                "mov.l  5f, %1\n\t"
-                "jmp    @%1\n\t"
-                " mov   %9, %0\n\t"
-                ".balign 4\n"
-                "5:     .long 3b\n"
-                ".previous\n"
-                ".section __ex_table,\"a\"\n"
-                "       .balign 4\n"
-                "       .long 9b,4b\n"
-                ".previous"
-                : "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d), "=r"(_c)
-                : "0" (__count), "2" (__src), "3" (__dest), "4" (__count),
-                  "i" (-EFAULT)
-                : "memory", "t");
-
-        return res;
-}
-
 /*
  * Return the size of a string (including the ending 0 even when we have
  * exceeded the maximum string length).
diff --git a/arch/sh/include/asm/uaccess_64.h b/arch/sh/include/asm/uaccess_64.h
index 56fd20b8cdcc..0042c9054b20 100644
--- a/arch/sh/include/asm/uaccess_64.h
+++ b/arch/sh/include/asm/uaccess_64.h
@@ -85,7 +85,5 @@ extern long __put_user_asm_q(void *, long);
 extern void __put_user_unknown(void);
 
 extern long __strnlen_user(const char *__s, long __n);
-extern int __strncpy_from_user(unsigned long __dest,
-               unsigned long __user __src, int __count);
 
 #endif /* __ASM_SH_UACCESS_64_H */
diff --git a/arch/sh/kernel/cpu/sh5/entry.S b/arch/sh/kernel/cpu/sh5/entry.S
index ff1f0e6e9bec..b7b3f63299b0 100644
--- a/arch/sh/kernel/cpu/sh5/entry.S
+++ b/arch/sh/kernel/cpu/sh5/entry.S
@@ -1569,46 +1569,6 @@ ___clear_user_exit:
 #endif /* CONFIG_MMU */
 
 /*
- * int __strncpy_from_user(unsigned long __dest, unsigned long __src,
- *                         int __count)
- *
- * Inputs:
- * (r2)  target address
- * (r3)  source address
- * (r4)  maximum size in bytes
- *
- * Ouputs:
- * (*r2) copied data
- * (r2)  -EFAULT (in case of faulting)
- *       copied data (otherwise)
- */
-        .global __strncpy_from_user
-__strncpy_from_user:
-        pta     ___strncpy_from_user1, tr0
-        pta     ___strncpy_from_user_done, tr1
-        or      r4, ZERO, r5            /* r5 = original count */
-        beq/u   r4, r63, tr1            /* early exit if r4==0 */
-        movi    -(EFAULT), r6           /* r6 = reply, no real fixup */
-        or      ZERO, ZERO, r7          /* r7 = data, clear top byte of data */
-
-___strncpy_from_user1:
-        ld.b    r3, 0, r7               /* Fault address: only in reading */
-        st.b    r2, 0, r7
-        addi    r2, 1, r2
-        addi    r3, 1, r3
-        beq/u   ZERO, r7, tr1
-        addi    r4, -1, r4              /* return real number of copied bytes */
-        bne/l   ZERO, r4, tr0
-
-___strncpy_from_user_done:
-        sub     r5, r4, r6              /* If done, return copied */
-
-___strncpy_from_user_exit:
-        or      r6, ZERO, r2
-        ptabs   LINK, tr0
-        blink   tr0, ZERO
-
-/*
  * extern long __strnlen_user(const char *__s, long __n)
  *
  * Inputs:
@@ -1982,7 +1942,6 @@ asm_uaccess_start:
         .long   ___copy_user2, ___copy_user_exit
         .long   ___clear_user1, ___clear_user_exit
 #endif
-        .long   ___strncpy_from_user1, ___strncpy_from_user_exit
         .long   ___strnlen_user1, ___strnlen_user_exit
         .long   ___get_user_asm_b1, ___get_user_asm_b_exit
         .long   ___get_user_asm_w1, ___get_user_asm_w_exit
diff --git a/arch/sh/kernel/sh_ksyms_64.c b/arch/sh/kernel/sh_ksyms_64.c
index 45afa5c51f67..3a3ba60e4f93 100644
--- a/arch/sh/kernel/sh_ksyms_64.c
+++ b/arch/sh/kernel/sh_ksyms_64.c
@@ -33,7 +33,6 @@ EXPORT_SYMBOL(__get_user_asm_w);
 EXPORT_SYMBOL(__get_user_asm_l);
 EXPORT_SYMBOL(__get_user_asm_q);
 EXPORT_SYMBOL(__strnlen_user);
-EXPORT_SYMBOL(__strncpy_from_user);
 EXPORT_SYMBOL(__clear_user);
 EXPORT_SYMBOL(copy_page);
 EXPORT_SYMBOL(__copy_user);