um: Rework uaccess code

Rework UML's uaccess code to reuse as much as possible
from asm-generic/uaccess.c.

Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 17 insertions, 30 deletions

diff --git a/arch/um/kernel/skas/uaccess.c b/arch/um/kernel/skas/uaccess.c
index 4ffb644d6c07..85ac8adb069b 100644
--- a/arch/um/kernel/skas/uaccess.c
+++ b/arch/um/kernel/skas/uaccess.c
@@ -87,10 +87,10 @@ static int do_op_one_page(unsigned long addr, int len, int is_write,
 	return n;
 }
 
-static int buffer_op(unsigned long addr, int len, int is_write,
-		     int (*op)(unsigned long, int, void *), void *arg)
+static long buffer_op(unsigned long addr, int len, int is_write,
+		      int (*op)(unsigned long, int, void *), void *arg)
 {
-	int size, remain, n;
+	long size, remain, n;
 
 	size = min(PAGE_ALIGN(addr) - addr, (unsigned long) len);
 	remain = len;
@@ -139,18 +139,16 @@ static int copy_chunk_from_user(unsigned long from, int len, void *arg)
 	return 0;
 }
 
-int copy_from_user(void *to, const void __user *from, int n)
+long __copy_from_user(void *to, const void __user *from, unsigned long n)
 {
 	if (segment_eq(get_fs(), KERNEL_DS)) {
 		memcpy(to, (__force void*)from, n);
 		return 0;
 	}
 
-	return access_ok(VERIFY_READ, from, n) ?
-	       buffer_op((unsigned long) from, n, 0, copy_chunk_from_user, &to):
-	       n;
+	return buffer_op((unsigned long) from, n, 0, copy_chunk_from_user, &to);
 }
-EXPORT_SYMBOL(copy_from_user);
+EXPORT_SYMBOL(__copy_from_user);
 
 static int copy_chunk_to_user(unsigned long to, int len, void *arg)
 {
@@ -161,18 +159,16 @@ static int copy_chunk_to_user(unsigned long to, int len, void *arg)
 	return 0;
 }
 
-int copy_to_user(void __user *to, const void *from, int n)
+long __copy_to_user(void __user *to, const void *from, unsigned long n)
 {
 	if (segment_eq(get_fs(), KERNEL_DS)) {
 		memcpy((__force void *) to, from, n);
 		return 0;
 	}
 
-	return access_ok(VERIFY_WRITE, to, n) ?
-	       buffer_op((unsigned long) to, n, 1, copy_chunk_to_user, &from) :
-	       n;
+	return buffer_op((unsigned long) to, n, 1, copy_chunk_to_user, &from);
 }
-EXPORT_SYMBOL(copy_to_user);
+EXPORT_SYMBOL(__copy_to_user);
 
 static int strncpy_chunk_from_user(unsigned long from, int len, void *arg)
 {
@@ -188,9 +184,9 @@ static int strncpy_chunk_from_user(unsigned long from, int len, void *arg)
 	return 0;
 }
 
-int strncpy_from_user(char *dst, const char __user *src, int count)
+long __strncpy_from_user(char *dst, const char __user *src, long count)
 {
-	int n;
+	long n;
 	char *ptr = dst;
 
 	if (segment_eq(get_fs(), KERNEL_DS)) {
@@ -198,16 +194,13 @@ int strncpy_from_user(char *dst, const char __user *src, int count)
 		return strnlen(dst, count);
 	}
 
-	if (!access_ok(VERIFY_READ, src, 1))
-		return -EFAULT;
-
 	n = buffer_op((unsigned long) src, count, 0, strncpy_chunk_from_user,
 		      &ptr);
 	if (n != 0)
 		return -EFAULT;
 	return strnlen(dst, count);
 }
-EXPORT_SYMBOL(strncpy_from_user);
+EXPORT_SYMBOL(__strncpy_from_user);
 
 static int clear_chunk(unsigned long addr, int len, void *unused)
 {
@@ -215,22 +208,16 @@ static int clear_chunk(unsigned long addr, int len, void *unused)
 	return 0;
 }
 
-int __clear_user(void __user *mem, int len)
-{
-	return buffer_op((unsigned long) mem, len, 1, clear_chunk, NULL);
-}
-
-int clear_user(void __user *mem, int len)
+unsigned long __clear_user(void __user *mem, unsigned long len)
 {
 	if (segment_eq(get_fs(), KERNEL_DS)) {
 		memset((__force void*)mem, 0, len);
 		return 0;
 	}
 
-	return access_ok(VERIFY_WRITE, mem, len) ?
-	       buffer_op((unsigned long) mem, len, 1, clear_chunk, NULL) : len;
+	return buffer_op((unsigned long) mem, len, 1, clear_chunk, NULL);
 }
-EXPORT_SYMBOL(clear_user);
+EXPORT_SYMBOL(__clear_user);
 
 static int strnlen_chunk(unsigned long str, int len, void *arg)
 {
@@ -244,7 +231,7 @@ static int strnlen_chunk(unsigned long str, int len, void *arg)
 	return 0;
 }
 
-int strnlen_user(const void __user *str, int len)
+long __strnlen_user(const void __user *str, long len)
 {
 	int count = 0, n;
 
@@ -256,4 +243,4 @@ int strnlen_user(const void __user *str, int len)
 		return count + 1;
 	return 0;
 }
-EXPORT_SYMBOL(strnlen_user);
+EXPORT_SYMBOL(__strnlen_user);