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Diffstat (limited to 'arch/m32r/include/asm/uaccess.h')
| -rw-r--r-- | arch/m32r/include/asm/uaccess.h | 693 |
1 files changed, 693 insertions, 0 deletions
diff --git a/arch/m32r/include/asm/uaccess.h b/arch/m32r/include/asm/uaccess.h new file mode 100644 index 00000000000..1c7047bea20 --- /dev/null +++ b/arch/m32r/include/asm/uaccess.h @@ -0,0 +1,693 @@ +#ifndef _ASM_M32R_UACCESS_H +#define _ASM_M32R_UACCESS_H + +/* + * linux/include/asm-m32r/uaccess.h + * + * M32R version. + * Copyright (C) 2004, 2006 Hirokazu Takata <takata at linux-m32r.org> + */ + +/* + * User space memory access functions + */ +#include <linux/errno.h> +#include <linux/thread_info.h> +#include <asm/page.h> +#include <asm/setup.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +/* + * The fs value determines whether argument validity checking should be + * performed or not. If get_fs() == USER_DS, checking is performed, with + * get_fs() == KERNEL_DS, checking is bypassed. + * + * For historical reasons, these macros are grossly misnamed. + */ + +#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) + +#ifdef CONFIG_MMU + +#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) +#define USER_DS MAKE_MM_SEG(PAGE_OFFSET) +#define get_ds() (KERNEL_DS) +#define get_fs() (current_thread_info()->addr_limit) +#define set_fs(x) (current_thread_info()->addr_limit = (x)) + +#else /* not CONFIG_MMU */ + +#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) +#define USER_DS MAKE_MM_SEG(0xFFFFFFFF) +#define get_ds() (KERNEL_DS) + +static inline mm_segment_t get_fs(void) +{ + return USER_DS; +} + +static inline void set_fs(mm_segment_t s) +{ +} + +#endif /* not CONFIG_MMU */ + +#define segment_eq(a,b) ((a).seg == (b).seg) + +#define __addr_ok(addr) \ + ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg)) + +/* + * 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, roksum; \ + __chk_user_ptr(addr); \ + asm ( \ + " cmpu %1, %1 ; clear cbit\n" \ + " addx %1, %3 ; set cbit if overflow\n" \ + " subx %0, %0\n" \ + " cmpu %4, %1\n" \ + " subx %0, %5\n" \ + : "=&r" (flag), "=r" (roksum) \ + : "1" (addr), "r" ((int)(size)), \ + "r" (current_thread_info()->addr_limit.seg), "r" (0) \ + : "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) (likely(__range_ok(addr,size) == 0)) +#else +static inline int access_ok(int type, const void *addr, unsigned long size) +{ + unsigned long val = (unsigned long)addr; + + return ((val >= memory_start) && ((val + size) < memory_end)); +} +#endif /* CONFIG_MMU */ + +/* + * The exception table consists of pairs of addresses: the first is the + * address of an instruction that is allowed to fault, and the second is + * the address at which the program should continue. No registers are + * modified, so it is entirely up to the continuation code to figure out + * what to do. + * + * All the routines below use bits of fixup code that are out of line + * with the main instruction path. This means when everything is well, + * we don't even have to jump over them. Further, they do not intrude + * on our cache or tlb entries. + */ + +struct exception_table_entry +{ + unsigned long insn, fixup; +}; + +extern int fixup_exception(struct pt_regs *regs); + +/* + * These are the main single-value transfer routines. They automatically + * use the right size if we just have the right pointer type. + * + * This gets kind of ugly. We want to return _two_ values in "get_user()" + * and yet we don't want to do any pointers, because that is too much + * of a performance impact. Thus we have a few rather ugly macros here, + * and hide all the uglyness from the user. + * + * The "__xxx" versions of the user access functions are versions that + * do not verify the address space, that must have been done previously + * with a separate "access_ok()" call (this is used when we do multiple + * accesses to the same area of user memory). + */ + +/* 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) \ + __get_user_check((x),(ptr),sizeof(*(ptr))) + +/** + * 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))) + +#define __get_user_nocheck(x,ptr,size) \ +({ \ + long __gu_err = 0; \ + unsigned long __gu_val; \ + might_sleep(); \ + __get_user_size(__gu_val,(ptr),(size),__gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +#define __get_user_check(x,ptr,size) \ +({ \ + long __gu_err = -EFAULT; \ + unsigned long __gu_val = 0; \ + const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ + might_sleep(); \ + if (access_ok(VERIFY_READ,__gu_addr,size)) \ + __get_user_size(__gu_val,__gu_addr,(size),__gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +extern long __get_user_bad(void); + +#define __get_user_size(x,ptr,size,retval) \ +do { \ + retval = 0; \ + __chk_user_ptr(ptr); \ + switch (size) { \ + case 1: __get_user_asm(x,ptr,retval,"ub"); break; \ + case 2: __get_user_asm(x,ptr,retval,"uh"); break; \ + case 4: __get_user_asm(x,ptr,retval,""); break; \ + default: (x) = __get_user_bad(); \ + } \ +} while (0) + +#define __get_user_asm(x, addr, err, itype) \ + __asm__ __volatile__( \ + " .fillinsn\n" \ + "1: ld"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") + +/** + * __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))) + + +#define __put_user_nocheck(x,ptr,size) \ +({ \ + long __pu_err; \ + might_sleep(); \ + __put_user_size((x),(ptr),(size),__pu_err); \ + __pu_err; \ +}) + + +#define __put_user_check(x,ptr,size) \ +({ \ + long __pu_err = -EFAULT; \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + might_sleep(); \ + if (access_ok(VERIFY_WRITE,__pu_addr,size)) \ + __put_user_size((x),__pu_addr,(size),__pu_err); \ + __pu_err; \ +}) + +#if defined(__LITTLE_ENDIAN__) +#define __put_user_u64(x, addr, err) \ + __asm__ __volatile__( \ + " .fillinsn\n" \ + "1: st %L1,@%2\n" \ + " .fillinsn\n" \ + "2: st %H1,@(4,%2)\n" \ + " .fillinsn\n" \ + "3:\n" \ + ".section .fixup,\"ax\"\n" \ + " .balign 4\n" \ + "4: ldi %0,%3\n" \ + " seth r14,#high(3b)\n" \ + " or3 r14,r14,#low(3b)\n" \ + " jmp r14\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 1b,4b\n" \ + " .long 2b,4b\n" \ + ".previous" \ + : "=&r" (err) \ + : "r" (x), "r" (addr), "i" (-EFAULT), "0" (err) \ + : "r14", "memory") + +#elif defined(__BIG_ENDIAN__) +#define __put_user_u64(x, addr, err) \ + __asm__ __volatile__( \ + " .fillinsn\n" \ + "1: st %H1,@%2\n" \ + " .fillinsn\n" \ + "2: st %L1,@(4,%2)\n" \ + " .fillinsn\n" \ + "3:\n" \ + ".section .fixup,\"ax\"\n" \ + " .balign 4\n" \ + "4: ldi %0,%3\n" \ + " seth r14,#high(3b)\n" \ + " or3 r14,r14,#low(3b)\n" \ + " jmp r14\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 1b,4b\n" \ + " .long 2b,4b\n" \ + ".previous" \ + : "=&r" (err) \ + : "r" (x), "r" (addr), "i" (-EFAULT), "0" (err) \ + : "r14", "memory") +#else +#error no endian defined +#endif + +extern void __put_user_bad(void); + +#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") + +/* + * 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 + */ + +/* Generic arbitrary sized copy. */ +/* Return the number of bytes NOT copied. */ +#define __copy_user(to,from,size) \ +do { \ + unsigned long __dst, __src, __c; \ + __asm__ __volatile__ ( \ + " mv r14, %0\n" \ + " or r14, %1\n" \ + " beq %0, %1, 9f\n" \ + " beqz %2, 9f\n" \ + " and3 r14, r14, #3\n" \ + " bnez r14, 2f\n" \ + " and3 %2, %2, #3\n" \ + " beqz %3, 2f\n" \ + " addi %0, #-4 ; word_copy \n" \ + " .fillinsn\n" \ + "0: ld r14, @%1+\n" \ + " addi %3, #-1\n" \ + " .fillinsn\n" \ + "1: st r14, @+%0\n" \ + " bnez %3, 0b\n" \ + " beqz %2, 9f\n" \ + " addi %0, #4\n" \ + " .fillinsn\n" \ + "2: ldb r14, @%1 ; byte_copy \n" \ + " .fillinsn\n" \ + "3: stb r14, @%0\n" \ + " addi %1, #1\n" \ + " addi %2, #-1\n" \ + " addi %0, #1\n" \ + " bnez %2, 2b\n" \ + " .fillinsn\n" \ + "9:\n" \ + ".section .fixup,\"ax\"\n" \ + " .balign 4\n" \ + "5: addi %3, #1\n" \ + " addi %1, #-4\n" \ + " .fillinsn\n" \ + "6: slli %3, #2\n" \ + " add %2, %3\n" \ + " addi %0, #4\n" \ + " .fillinsn\n" \ + "7: seth r14, #high(9b)\n" \ + " or3 r14, r14, #low(9b)\n" \ + " jmp r14\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 0b,6b\n" \ + " .long 1b,5b\n" \ + " .long 2b,9b\n" \ + " .long 3b,9b\n" \ + ".previous\n" \ + : "=&r" (__dst), "=&r" (__src), "=&r" (size), \ + "=&r" (__c) \ + : "0" (to), "1" (from), "2" (size), "3" (size / 4) \ + : "r14", "memory"); \ +} while (0) + +#define __copy_user_zeroing(to,from,size) \ +do { \ + unsigned long __dst, __src, __c; \ + __asm__ __volatile__ ( \ + " mv r14, %0\n" \ + " or r14, %1\n" \ + " beq %0, %1, 9f\n" \ + " beqz %2, 9f\n" \ + " and3 r14, r14, #3\n" \ + " bnez r14, 2f\n" \ + " and3 %2, %2, #3\n" \ + " beqz %3, 2f\n" \ + " addi %0, #-4 ; word_copy \n" \ + " .fillinsn\n" \ + "0: ld r14, @%1+\n" \ + " addi %3, #-1\n" \ + " .fillinsn\n" \ + "1: st r14, @+%0\n" \ + " bnez %3, 0b\n" \ + " beqz %2, 9f\n" \ + " addi %0, #4\n" \ + " .fillinsn\n" \ + "2: ldb r14, @%1 ; byte_copy \n" \ + " .fillinsn\n" \ + "3: stb r14, @%0\n" \ + " addi %1, #1\n" \ + " addi %2, #-1\n" \ + " addi %0, #1\n" \ + " bnez %2, 2b\n" \ + " .fillinsn\n" \ + "9:\n" \ + ".section .fixup,\"ax\"\n" \ + " .balign 4\n" \ + "5: addi %3, #1\n" \ + " addi %1, #-4\n" \ + " .fillinsn\n" \ + "6: slli %3, #2\n" \ + " add %2, %3\n" \ + " addi %0, #4\n" \ + " .fillinsn\n" \ + "7: ldi r14, #0 ; store zero \n" \ + " .fillinsn\n" \ + "8: addi %2, #-1\n" \ + " stb r14, @%0 ; ACE? \n" \ + " addi %0, #1\n" \ + " bnez %2, 8b\n" \ + " seth r14, #high(9b)\n" \ + " or3 r14, r14, #low(9b)\n" \ + " jmp r14\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 0b,6b\n" \ + " .long 1b,5b\n" \ + " .long 2b,7b\n" \ + " .long 3b,7b\n" \ + ".previous\n" \ + : "=&r" (__dst), "=&r" (__src), "=&r" (size), \ + "=&r" (__c) \ + : "0" (to), "1" (from), "2" (size), "3" (size / 4) \ + : "r14", "memory"); \ +} while (0) + + +/* 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, + 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, + const void *from, unsigned long n) +{ + __copy_user(to,from,n); + return n; +} + +unsigned long __generic_copy_to_user(void __user *, const void *, unsigned long); +unsigned long __generic_copy_from_user(void *, const void __user *, 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)); \ +}) + +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); + +/** + * 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); + +/** + * 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); + +#endif /* _ASM_M32R_UACCESS_H */ |