csky: uaccess.h: Coding convention with asm generic

Using asm-generic/uaccess.h to prevent duplicated code:
 - Add user_addr_max which mentioned in generic uaccess.h
 - Remove custom definitions of KERNEL/USER_DS, get/set_fs,
   uaccess_kerenl
 - Using generic extable.h instead of custom definitions in
   uaccess.h

Change v2:
 - Fixup tinyconfig compile error, "__put_user_bad"
 - Add __get_user_asm_64

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Link: https://lore.kernel.org/linux-csky/CAK8P3a1DvsXSEDoovLk11hzNHyJi7vqNoToU+n5aFi2viZO_Uw@mail.gmail.com/T/#mbcd58a0e3450e5598974116b607589afa16a3ab7
Cc: Arnd Bergmann <arnd@arndb.de>

1 files changed, 211 insertions, 153 deletions

diff --git a/arch/csky/lib/usercopy.c b/arch/csky/lib/usercopy.c
index 3c9bd645e643..a71836056fc8 100644
--- a/arch/csky/lib/usercopy.c
+++ b/arch/csky/lib/usercopy.c
@@ -7,7 +7,70 @@
 unsigned long raw_copy_from_user(void *to, const void *from,
 			unsigned long n)
 {
-	___copy_from_user(to, from, n);
+	int tmp, nsave;
+
+	__asm__ __volatile__(
+	"0:     cmpnei  %1, 0           \n"
+	"       bf      7f              \n"
+	"       mov     %3, %1          \n"
+	"       or      %3, %2          \n"
+	"       andi    %3, 3           \n"
+	"       cmpnei  %3, 0           \n"
+	"       bf      1f              \n"
+	"       br      5f              \n"
+	"1:     cmplti  %0, 16          \n"
+	"       bt      3f              \n"
+	"2:     ldw     %3, (%2, 0)     \n"
+	"10:    ldw     %4, (%2, 4)     \n"
+	"       stw     %3, (%1, 0)     \n"
+	"       stw     %4, (%1, 4)     \n"
+	"11:    ldw     %3, (%2, 8)     \n"
+	"12:    ldw     %4, (%2, 12)    \n"
+	"       stw     %3, (%1, 8)     \n"
+	"       stw     %4, (%1, 12)    \n"
+	"       addi    %2, 16          \n"
+	"       addi    %1, 16          \n"
+	"       subi    %0, 16          \n"
+	"       br      1b              \n"
+	"3:     cmplti  %0, 4           \n"
+	"       bt      5f              \n"
+	"4:     ldw     %3, (%2, 0)     \n"
+	"       stw     %3, (%1, 0)     \n"
+	"       addi    %2, 4           \n"
+	"       addi    %1, 4           \n"
+	"       subi    %0, 4           \n"
+	"       br      3b              \n"
+	"5:     cmpnei  %0, 0           \n"
+	"       bf      7f              \n"
+	"6:     ldb     %3, (%2, 0)     \n"
+	"       stb     %3, (%1, 0)     \n"
+	"       addi    %2,  1          \n"
+	"       addi    %1,  1          \n"
+	"       subi    %0,  1          \n"
+	"       br      5b              \n"
+	"8:     stw     %3, (%1, 0)     \n"
+	"       subi    %0, 4           \n"
+	"       bf      7f              \n"
+	"9:     subi    %0, 8           \n"
+	"       bf      7f              \n"
+	"13:    stw     %3, (%1, 8)     \n"
+	"       subi    %0, 12          \n"
+	"       bf      7f              \n"
+	".section __ex_table, \"a\"     \n"
+	".align   2                     \n"
+	".long    2b, 7f                \n"
+	".long    4b, 7f                \n"
+	".long    6b, 7f                \n"
+	".long   10b, 8b                \n"
+	".long   11b, 9b                \n"
+	".long   12b,13b                \n"
+	".previous                      \n"
+	"7:                             \n"
+	: "=r"(n), "=r"(to), "=r"(from), "=r"(nsave),
+	  "=r"(tmp)
+	: "0"(n), "1"(to), "2"(from)
+	: "memory");
+
 	return n;
 }
 EXPORT_SYMBOL(raw_copy_from_user);
@@ -15,48 +78,70 @@ EXPORT_SYMBOL(raw_copy_from_user);
 unsigned long raw_copy_to_user(void *to, const void *from,
 			unsigned long n)
 {
-	___copy_to_user(to, from, n);
+	int w0, w1, w2, w3;
+
+	__asm__ __volatile__(
+	"0:     cmpnei  %1, 0           \n"
+	"       bf      8f              \n"
+	"       mov     %3, %1          \n"
+	"       or      %3, %2          \n"
+	"       andi    %3, 3           \n"
+	"       cmpnei  %3, 0           \n"
+	"       bf      1f              \n"
+	"       br      5f              \n"
+	"1:     cmplti  %0, 16          \n" /* 4W */
+	"       bt      3f              \n"
+	"       ldw     %3, (%2, 0)     \n"
+	"       ldw     %4, (%2, 4)     \n"
+	"       ldw     %5, (%2, 8)     \n"
+	"       ldw     %6, (%2, 12)    \n"
+	"2:     stw     %3, (%1, 0)     \n"
+	"9:     stw     %4, (%1, 4)     \n"
+	"10:    stw     %5, (%1, 8)     \n"
+	"11:    stw     %6, (%1, 12)    \n"
+	"       addi    %2, 16          \n"
+	"       addi    %1, 16          \n"
+	"       subi    %0, 16          \n"
+	"       br      1b              \n"
+	"3:     cmplti  %0, 4           \n" /* 1W */
+	"       bt      5f              \n"
+	"       ldw     %3, (%2, 0)     \n"
+	"4:     stw     %3, (%1, 0)     \n"
+	"       addi    %2, 4           \n"
+	"       addi    %1, 4           \n"
+	"       subi    %0, 4           \n"
+	"       br      3b              \n"
+	"5:     cmpnei  %0, 0           \n"  /* 1B */
+	"       bf      13f             \n"
+	"       ldb     %3, (%2, 0)     \n"
+	"6:     stb     %3, (%1, 0)     \n"
+	"       addi    %2,  1          \n"
+	"       addi    %1,  1          \n"
+	"       subi    %0,  1          \n"
+	"       br      5b              \n"
+	"7:     subi	%0,  4          \n"
+	"8:     subi	%0,  4          \n"
+	"12:    subi	%0,  4          \n"
+	"       br      13f             \n"
+	".section __ex_table, \"a\"     \n"
+	".align   2                     \n"
+	".long    2b, 13f               \n"
+	".long    4b, 13f               \n"
+	".long    6b, 13f               \n"
+	".long    9b, 12b               \n"
+	".long   10b, 8b                \n"
+	".long   11b, 7b                \n"
+	".previous                      \n"
+	"13:                            \n"
+	: "=r"(n), "=r"(to), "=r"(from), "=r"(w0),
+	  "=r"(w1), "=r"(w2), "=r"(w3)
+	: "0"(n), "1"(to), "2"(from)
+	: "memory");
+
 	return n;
 }
 EXPORT_SYMBOL(raw_copy_to_user);
 
-
-/*
- * copy a null terminated string from userspace.
- */
-#define __do_strncpy_from_user(dst, src, count, res)	\
-do {							\
-	int tmp;					\
-	long faultres;					\
-	asm volatile(					\
-	"       cmpnei  %3, 0           \n"		\
-	"       bf      4f              \n"		\
-	"1:     cmpnei  %1, 0          	\n"		\
-	"       bf      5f              \n"		\
-	"2:     ldb     %4, (%3, 0)     \n"		\
-	"       stb     %4, (%2, 0)     \n"		\
-	"       cmpnei  %4, 0           \n"		\
-	"       bf      3f              \n"		\
-	"       addi    %3,  1          \n"		\
-	"       addi    %2,  1          \n"		\
-	"       subi    %1,  1          \n"		\
-	"       br      1b              \n"		\
-	"3:     subu	%0, %1          \n"		\
-	"       br      5f              \n"		\
-	"4:     mov     %0, %5          \n"		\
-	"       br      5f              \n"		\
-	".section __ex_table, \"a\"     \n"		\
-	".align   2                     \n"		\
-	".long    2b, 4b                \n"		\
-	".previous                      \n"		\
-	"5:                             \n"		\
-	: "=r"(res), "=r"(count), "=r"(dst),		\
-	  "=r"(src), "=r"(tmp),   "=r"(faultres)	\
-	: "5"(-EFAULT), "0"(count), "1"(count),		\
-	  "2"(dst), "3"(src)				\
-	: "memory", "cc");				\
-} while (0)
-
 /*
  * __strncpy_from_user: - Copy a NUL terminated string from userspace,
  * with less checking.
@@ -80,40 +165,40 @@ do {							\
  */
 long __strncpy_from_user(char *dst, const char *src, long count)
 {
-	long res;
+	long res, faultres;
+	int tmp;
 
-	__do_strncpy_from_user(dst, src, count, res);
-	return res;
-}
-EXPORT_SYMBOL(__strncpy_from_user);
-
-/*
- * 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.
- */
-long strncpy_from_user(char *dst, const char *src, long count)
-{
-	long res = -EFAULT;
+	__asm__ __volatile__(
+	"       cmpnei  %3, 0           \n"
+	"       bf      4f              \n"
+	"1:     cmpnei  %1, 0          	\n"
+	"       bf      5f              \n"
+	"2:     ldb     %4, (%3, 0)     \n"
+	"       stb     %4, (%2, 0)     \n"
+	"       cmpnei  %4, 0           \n"
+	"       bf      3f              \n"
+	"       addi    %3,  1          \n"
+	"       addi    %2,  1          \n"
+	"       subi    %1,  1          \n"
+	"       br      1b              \n"
+	"3:     subu	%0, %1          \n"
+	"       br      5f              \n"
+	"4:     mov     %0, %5          \n"
+	"       br      5f              \n"
+	".section __ex_table, \"a\"     \n"
+	".align   2                     \n"
+	".long    2b, 4b                \n"
+	".previous                      \n"
+	"5:                             \n"
+	: "=r"(res), "=r"(count), "=r"(dst),
+	  "=r"(src), "=r"(tmp), "=r"(faultres)
+	: "5"(-EFAULT), "0"(count), "1"(count),
+	  "2"(dst), "3"(src)
+	: "memory");
 
-	if (access_ok(src, 1))
-		__do_strncpy_from_user(dst, src, count, res);
 	return res;
 }
-EXPORT_SYMBOL(strncpy_from_user);
+EXPORT_SYMBOL(__strncpy_from_user);
 
 /*
  * strlen_user: - Get the size of a string in user space.
@@ -126,14 +211,11 @@ EXPORT_SYMBOL(strncpy_from_user);
  * On exception, returns 0.
  * If the string is too long, returns a value greater than @n.
  */
-long strnlen_user(const char *s, long n)
+long __strnlen_user(const char *s, long n)
 {
 	unsigned long res, tmp;
 
-	if (s == NULL)
-		return 0;
-
-	asm volatile(
+	__asm__ __volatile__(
 	"       cmpnei  %1, 0           \n"
 	"       bf      3f              \n"
 	"1:     cmpnei  %0, 0           \n"
@@ -156,87 +238,11 @@ long strnlen_user(const char *s, long n)
 	"5:                             \n"
 	: "=r"(n), "=r"(s), "=r"(res), "=r"(tmp)
 	: "0"(n), "1"(s), "2"(n)
-	: "memory", "cc");
+	: "memory");
 
 	return res;
 }
-EXPORT_SYMBOL(strnlen_user);
-
-#define __do_clear_user(addr, size)			\
-do {							\
-	int __d0, zvalue, tmp;				\
-							\
-	asm volatile(					\
-	"0:     cmpnei  %1, 0           \n"		\
-	"       bf      7f              \n"		\
-	"       mov     %3, %1          \n"		\
-	"       andi    %3, 3           \n"		\
-	"       cmpnei  %3, 0           \n"		\
-	"       bf      1f              \n"		\
-	"       br      5f              \n"		\
-	"1:     cmplti  %0, 32          \n" /* 4W */	\
-	"       bt      3f              \n"		\
-	"8:     stw     %2, (%1, 0)     \n"		\
-	"10:    stw     %2, (%1, 4)     \n"		\
-	"11:    stw     %2, (%1, 8)     \n"		\
-	"12:    stw     %2, (%1, 12)    \n"		\
-	"13:    stw     %2, (%1, 16)    \n"		\
-	"14:    stw     %2, (%1, 20)    \n"		\
-	"15:    stw     %2, (%1, 24)    \n"		\
-	"16:    stw     %2, (%1, 28)    \n"		\
-	"       addi    %1, 32          \n"		\
-	"       subi    %0, 32          \n"		\
-	"       br      1b              \n"		\
-	"3:     cmplti  %0, 4           \n" /* 1W */	\
-	"       bt      5f              \n"		\
-	"4:     stw     %2, (%1, 0)     \n"		\
-	"       addi    %1, 4           \n"		\
-	"       subi    %0, 4           \n"		\
-	"       br      3b              \n"		\
-	"5:     cmpnei  %0, 0           \n" /* 1B */	\
-	"9:     bf      7f              \n"		\
-	"6:     stb     %2, (%1, 0)     \n"		\
-	"       addi    %1,  1          \n"		\
-	"       subi    %0,  1          \n"		\
-	"       br      5b              \n"		\
-	".section __ex_table,\"a\"      \n"		\
-	".align   2                     \n"		\
-	".long    8b, 9b                \n"		\
-	".long    10b, 9b               \n"		\
-	".long    11b, 9b               \n"		\
-	".long    12b, 9b               \n"		\
-	".long    13b, 9b               \n"		\
-	".long    14b, 9b               \n"		\
-	".long    15b, 9b               \n"		\
-	".long    16b, 9b               \n"		\
-	".long    4b, 9b                \n"		\
-	".long    6b, 9b                \n"		\
-	".previous                      \n"		\
-	"7:                             \n"		\
-	: "=r"(size), "=r" (__d0),			\
-	  "=r"(zvalue), "=r"(tmp)			\
-	: "0"(size), "1"(addr), "2"(0)			\
-	: "memory", "cc");				\
-} while (0)
-
-/*
- * clear_user: - Zero a block of memory in user space.
- * @to:   Destination address, in user space.
- * @n:    Number of bytes to zero.
- *
- * Zero a block of memory in user space.
- *
- * Returns number of bytes that could not be cleared.
- * On success, this will be zero.
- */
-unsigned long
-clear_user(void __user *to, unsigned long n)
-{
-	if (access_ok(to, n))
-		__do_clear_user(to, n);
-	return n;
-}
-EXPORT_SYMBOL(clear_user);
+EXPORT_SYMBOL(__strnlen_user);
 
 /*
  * __clear_user: - Zero a block of memory in user space, with less checking.
@@ -252,7 +258,59 @@ EXPORT_SYMBOL(clear_user);
 unsigned long
 __clear_user(void __user *to, unsigned long n)
 {
-	__do_clear_user(to, n);
+	int data, value, tmp;
+
+	__asm__ __volatile__(
+	"0:     cmpnei  %1, 0           \n"
+	"       bf      7f              \n"
+	"       mov     %3, %1          \n"
+	"       andi    %3, 3           \n"
+	"       cmpnei  %3, 0           \n"
+	"       bf      1f              \n"
+	"       br      5f              \n"
+	"1:     cmplti  %0, 32          \n" /* 4W */
+	"       bt      3f              \n"
+	"8:     stw     %2, (%1, 0)     \n"
+	"10:    stw     %2, (%1, 4)     \n"
+	"11:    stw     %2, (%1, 8)     \n"
+	"12:    stw     %2, (%1, 12)    \n"
+	"13:    stw     %2, (%1, 16)    \n"
+	"14:    stw     %2, (%1, 20)    \n"
+	"15:    stw     %2, (%1, 24)    \n"
+	"16:    stw     %2, (%1, 28)    \n"
+	"       addi    %1, 32          \n"
+	"       subi    %0, 32          \n"
+	"       br      1b              \n"
+	"3:     cmplti  %0, 4           \n" /* 1W */
+	"       bt      5f              \n"
+	"4:     stw     %2, (%1, 0)     \n"
+	"       addi    %1, 4           \n"
+	"       subi    %0, 4           \n"
+	"       br      3b              \n"
+	"5:     cmpnei  %0, 0           \n" /* 1B */
+	"9:     bf      7f              \n"
+	"6:     stb     %2, (%1, 0)     \n"
+	"       addi    %1,  1          \n"
+	"       subi    %0,  1          \n"
+	"       br      5b              \n"
+	".section __ex_table,\"a\"      \n"
+	".align   2                     \n"
+	".long    8b, 9b                \n"
+	".long    10b, 9b               \n"
+	".long    11b, 9b               \n"
+	".long    12b, 9b               \n"
+	".long    13b, 9b               \n"
+	".long    14b, 9b               \n"
+	".long    15b, 9b               \n"
+	".long    16b, 9b               \n"
+	".long    4b, 9b                \n"
+	".long    6b, 9b                \n"
+	".previous                      \n"
+	"7:                             \n"
+	: "=r"(n), "=r" (data), "=r"(value), "=r"(tmp)
+	: "0"(n), "1"(to), "2"(0)
+	: "memory");
+
 	return n;
 }
 EXPORT_SYMBOL(__clear_user);