From: Hirokazu Takata This patch updates asm-m32r/uaccess.h. * include/asm-m32r/uaccess.h: (__copy_to_user_inatomic): Added. (__copy_from_user_inatomic): Added. Update comments. Signed-off-by: Hirokazu Takata Signed-off-by: Andrew Morton --- 25-akpm/include/asm-m32r/uaccess.h | 349 ++++++++++++++++++++++++++++++------- 1 files changed, 290 insertions(+), 59 deletions(-) diff -puN include/asm-m32r/uaccess.h~m32r-update-uaccessh include/asm-m32r/uaccess.h --- 25/include/asm-m32r/uaccess.h~m32r-update-uaccessh 2004-09-11 16:37:06.582581928 -0700 +++ 25-akpm/include/asm-m32r/uaccess.h 2004-09-11 16:37:06.588581016 -0700 @@ -1,7 +1,12 @@ #ifndef _ASM_M32R_UACCESS_H #define _ASM_M32R_UACCESS_H -/* $Id$ */ +/* + * linux/include/asm-m32r/uaccess.h + * + * M32R version. + * Copyright (C) 2004 Hirokazu Takata + */ #undef UACCESS_DEBUG @@ -61,7 +66,13 @@ static inline void set_fs(mm_segment_t s ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg)) /* - * Uhhuh, this needs 33-bit arithmetic. We have a carry.. + * Test whether a block of memory is a valid user space address. + * Returns 0 if the range is valid, nonzero otherwise. + * + * This is equivalent to the following test: + * (u33)addr + (u33)size >= (u33)current->addr_limit.seg + * + * This needs 33-bit arithmetic. We have a carry... */ #define __range_ok(addr,size) ({ \ unsigned long flag, sum; \ @@ -78,8 +89,27 @@ static inline void set_fs(mm_segment_t s : "cbit" ); \ flag; }) +/** + * access_ok: - Checks if a user space pointer is valid + * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that + * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe + * to write to a block, it is always safe to read from it. + * @addr: User space pointer to start of block to check + * @size: Size of block to check + * + * Context: User context only. This function may sleep. + * + * Checks if a pointer to a block of memory in user space is valid. + * + * Returns true (nonzero) if the memory block may be valid, false (zero) + * if it is definitely invalid. + * + * Note that, depending on architecture, this function probably just + * checks that the pointer is in the user space range - after calling + * this function, memory access functions may still return -EFAULT. + */ #ifdef CONFIG_MMU -#define access_ok(type,addr,size) (__range_ok(addr,size) == 0) +#define access_ok(type,addr,size) (likely(__range_ok(addr,size) == 0)) #else static inline int access_ok(int type, const void *addr, unsigned long size) { @@ -90,8 +120,25 @@ static inline int access_ok(int type, co } #endif /* CONFIG_MMU */ -static __inline__ int verify_area(int type, const void __user *addr, - unsigned long size) +/** + * verify_area: - Obsolete, use access_ok() + * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE + * @addr: User space pointer to start of block to check + * @size: Size of block to check + * + * Context: User context only. This function may sleep. + * + * This function has been replaced by access_ok(). + * + * Checks if a pointer to a block of memory in user space is valid. + * + * Returns zero if the memory block may be valid, -EFAULT + * if it is definitely invalid. + * + * See access_ok() for more details. + */ +static inline int verify_area(int type, const void __user *addr, + unsigned long size) { return access_ok(type, addr, size) ? 0 : -EFAULT; } @@ -167,6 +214,23 @@ extern void __get_user_4(void); /* Careful: we have to cast the result to the type of the pointer for sign reasons */ +/** + * get_user: - Get a simple variable from user space. + * @x: Variable to store result. + * @ptr: Source address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple variable from user space to kernel + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and the result of + * dereferencing @ptr must be assignable to @x without a cast. + * + * Returns zero on success, or -EFAULT on error. + * On error, the variable @x is set to zero. + */ #define get_user(x,ptr) \ ({ int __ret_gu,__val_gu; \ __chk_user_ptr(ptr); \ @@ -182,11 +246,69 @@ extern void __get_user_4(void); extern void __put_user_bad(void); +/** + * put_user: - Write a simple value into user space. + * @x: Value to copy to user space. + * @ptr: Destination address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple value from kernel space to user + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and @x must be assignable + * to the result of dereferencing @ptr. + * + * Returns zero on success, or -EFAULT on error. + */ #define put_user(x,ptr) \ __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr))) + +/** + * __get_user: - Get a simple variable from user space, with less checking. + * @x: Variable to store result. + * @ptr: Source address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple variable from user space to kernel + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and the result of + * dereferencing @ptr must be assignable to @x without a cast. + * + * Caller must check the pointer with access_ok() before calling this + * function. + * + * Returns zero on success, or -EFAULT on error. + * On error, the variable @x is set to zero. + */ #define __get_user(x,ptr) \ __get_user_nocheck((x),(ptr),sizeof(*(ptr))) + + +/** + * __put_user: - Write a simple value into user space, with less checking. + * @x: Value to copy to user space. + * @ptr: Destination address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple value from kernel space to user + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and @x must be assignable + * to the result of dereferencing @ptr. + * + * Caller must check the pointer with access_ok() before calling this + * function. + * + * Returns zero on success, or -EFAULT on error. + */ #define __put_user(x,ptr) \ __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr))) @@ -208,48 +330,6 @@ extern void __put_user_bad(void); __pu_err; \ }) -#define __put_user_size(x,ptr,size,retval) \ -do { \ - retval = 0; \ - __chk_user_ptr(ptr); \ - switch (size) { \ - case 1: __put_user_asm(x,ptr,retval,"b"); break; \ - case 2: __put_user_asm(x,ptr,retval,"h"); break; \ - case 4: __put_user_asm(x,ptr,retval,""); break; \ - case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\ - default: __put_user_bad(); \ - } \ -} while (0) - -struct __large_struct { unsigned long buf[100]; }; -#define __m(x) (*(struct __large_struct *)(x)) - -/* - * Tell gcc we read from memory instead of writing: this is because - * we do not write to any memory gcc knows about, so there are no - * aliasing issues. - */ -#define __put_user_asm(x, addr, err, itype) \ - __asm__ __volatile__( \ - " .fillinsn\n" \ - "1: st"itype" %1,@%2\n" \ - " .fillinsn\n" \ - "2:\n" \ - ".section .fixup,\"ax\"\n" \ - " .balign 4\n" \ - "3: ldi %0,%3\n" \ - " seth r14,#high(2b)\n" \ - " or3 r14,r14,#low(2b)\n" \ - " jmp r14\n" \ - ".previous\n" \ - ".section __ex_table,\"a\"\n" \ - " .balign 4\n" \ - " .long 1b,3b\n" \ - ".previous" \ - : "=r"(err) \ - : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err) \ - : "r14", "memory") - #if defined(__LITTLE_ENDIAN__) #define __put_user_u64(x, addr, err) \ __asm__ __volatile__( \ @@ -307,6 +387,48 @@ struct __large_struct { unsigned long bu #error no endian defined #endif +#define __put_user_size(x,ptr,size,retval) \ +do { \ + retval = 0; \ + __chk_user_ptr(ptr); \ + switch (size) { \ + case 1: __put_user_asm(x,ptr,retval,"b"); break; \ + case 2: __put_user_asm(x,ptr,retval,"h"); break; \ + case 4: __put_user_asm(x,ptr,retval,""); break; \ + case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\ + default: __put_user_bad(); \ + } \ +} while (0) + +struct __large_struct { unsigned long buf[100]; }; +#define __m(x) (*(struct __large_struct *)(x)) + +/* + * Tell gcc we read from memory instead of writing: this is because + * we do not write to any memory gcc knows about, so there are no + * aliasing issues. + */ +#define __put_user_asm(x, addr, err, itype) \ + __asm__ __volatile__( \ + " .fillinsn\n" \ + "1: st"itype" %1,@%2\n" \ + " .fillinsn\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + " .balign 4\n" \ + "3: ldi %0,%3\n" \ + " seth r14,#high(2b)\n" \ + " or3 r14,r14,#low(2b)\n" \ + " jmp r14\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 1b,3b\n" \ + ".previous" \ + : "=r"(err) \ + : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err) \ + : "r14", "memory") + #define __get_user_nocheck(x,ptr,size) \ ({ \ long __gu_err, __gu_val; \ @@ -350,6 +472,13 @@ do { \ : "r"(addr), "i"(-EFAULT), "0"(err) \ : "r14", "memory") +/* + * Here we special-case 1, 2 and 4-byte copy_*_user invocations. On a fault + * we return the initial request size (1, 2 or 4), as copy_*_user should do. + * If a store crosses a page boundary and gets a fault, the m32r will not write + * anything, so this is accurate. + */ + /* * Copy To/From Userspace @@ -479,14 +608,14 @@ do { \ /* We let the __ versions of copy_from/to_user inline, because they're often * used in fast paths and have only a small space overhead. */ -static __inline__ unsigned long __generic_copy_from_user_nocheck(void *to, +static inline unsigned long __generic_copy_from_user_nocheck(void *to, const void __user *from, unsigned long n) { __copy_user_zeroing(to,from,n); return n; } -static __inline__ unsigned long __generic_copy_to_user_nocheck(void __user *to, +static inline unsigned long __generic_copy_to_user_nocheck(void __user *to, const void *from, unsigned long n) { __copy_user(to,from,n); @@ -496,30 +625,132 @@ static __inline__ unsigned long __generi unsigned long __generic_copy_to_user(void *, const void *, unsigned long); unsigned long __generic_copy_from_user(void *, const void *, unsigned long); +/** + * __copy_to_user: - Copy a block of data into user space, with less checking. + * @to: Destination address, in user space. + * @from: Source address, in kernel space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from kernel space to user space. Caller must check + * the specified block with access_ok() before calling this function. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + */ +#define __copy_to_user(to,from,n) \ + __generic_copy_to_user_nocheck((to),(from),(n)) + +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user + +/** + * copy_to_user: - Copy a block of data into user space. + * @to: Destination address, in user space. + * @from: Source address, in kernel space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from kernel space to user space. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + */ #define copy_to_user(to,from,n) \ ({ \ might_sleep(); \ __generic_copy_to_user((to),(from),(n)); \ }) +/** + * __copy_from_user: - Copy a block of data from user space, with less checking. * @to: Destination address, in kernel space. + * @from: Source address, in user space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from user space to kernel space. Caller must check + * the specified block with access_ok() before calling this function. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + * + * If some data could not be copied, this function will pad the copied + * data to the requested size using zero bytes. + */ +#define __copy_from_user(to,from,n) \ + __generic_copy_from_user_nocheck((to),(from),(n)) + +/** + * copy_from_user: - Copy a block of data from user space. + * @to: Destination address, in kernel space. + * @from: Source address, in user space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from user space to kernel space. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + * + * If some data could not be copied, this function will pad the copied + * data to the requested size using zero bytes. + */ #define copy_from_user(to,from,n) \ ({ \ might_sleep(); \ - __generic_copy_from_user((to),(from),(n)); \ +__generic_copy_from_user((to),(from),(n)); \ }) -#define __copy_to_user(to,from,n) \ - __generic_copy_to_user_nocheck((to),(from),(n)) +long __must_check strncpy_from_user(char *dst, const char __user *src, + long count); +long __must_check __strncpy_from_user(char *dst, + const char __user *src, long count); + +/** + * __clear_user: - Zero a block of memory in user space, with less checking. + * @to: Destination address, in user space. + * @n: Number of bytes to zero. + * + * Zero a block of memory in user space. Caller must check + * the specified block with access_ok() before calling this function. + * + * Returns number of bytes that could not be cleared. + * On success, this will be zero. + */ +unsigned long __clear_user(void __user *mem, unsigned long len); -#define __copy_from_user(to,from,n) \ - __generic_copy_from_user_nocheck((to),(from),(n)) +/** + * 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. Caller must check + * the specified block with access_ok() before calling this function. + * + * Returns number of bytes that could not be cleared. + * On success, this will be zero. + */ +unsigned long clear_user(void __user *mem, unsigned long len); -long strncpy_from_user(char *dst, const char __user *src, long count); -long __strncpy_from_user(char *dst, const char __user *src, long count); +/** + * strlen_user: - Get the size of a string in user space. + * @str: The string to measure. + * + * Context: User context only. This function may sleep. + * + * Get the size of a NUL-terminated string in user space. + * + * Returns the size of the string INCLUDING the terminating NUL. + * On exception, returns 0. + * + * If there is a limit on the length of a valid string, you may wish to + * consider using strnlen_user() instead. + */ #define strlen_user(str) strnlen_user(str, ~0UL >> 1) long strnlen_user(const char __user *str, long n); -unsigned long clear_user(void __user *mem, unsigned long len); -unsigned long __clear_user(void __user *mem, unsigned long len); #endif /* _ASM_M32R_UACCESS_H */ - _