| /* |
| * linux/include/asm-arm/uaccess.h |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| #ifndef _ASMARM_UACCESS_H |
| #define _ASMARM_UACCESS_H |
| |
| /* |
| * User space memory access functions |
| */ |
| #include <linux/sched.h> |
| #include <asm/errno.h> |
| #include <asm/memory.h> |
| #include <asm/domain.h> |
| #include <asm/system.h> |
| |
| #define VERIFY_READ 0 |
| #define VERIFY_WRITE 1 |
| |
| /* |
| * 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); |
| |
| /* |
| * Note that this is actually 0x1,0000,0000 |
| */ |
| #define KERNEL_DS 0x00000000 |
| #define USER_DS TASK_SIZE |
| |
| #define get_ds() (KERNEL_DS) |
| #define get_fs() (current_thread_info()->addr_limit) |
| |
| static inline void set_fs (mm_segment_t fs) |
| { |
| current_thread_info()->addr_limit = fs; |
| modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER); |
| } |
| |
| #define segment_eq(a,b) ((a) == (b)) |
| |
| #define __addr_ok(addr) ({ \ |
| unsigned long flag; \ |
| __asm__("cmp %2, %0; movlo %0, #0" \ |
| : "=&r" (flag) \ |
| : "0" (current_thread_info()->addr_limit), "r" (addr) \ |
| : "cc"); \ |
| (flag == 0); }) |
| |
| /* We use 33-bit arithmetic here... */ |
| #define __range_ok(addr,size) ({ \ |
| unsigned long flag, sum; \ |
| __chk_user_ptr(addr); \ |
| __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \ |
| : "=&r" (flag), "=&r" (sum) \ |
| : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \ |
| : "cc"); \ |
| flag; }) |
| |
| #define access_ok(type,addr,size) (__range_ok(addr,size) == 0) |
| |
| /* |
| * Single-value transfer routines. They automatically use the right |
| * size if we just have the right pointer type. Note that the functions |
| * which read from user space (*get_*) need to take care not to leak |
| * kernel data even if the calling code is buggy and fails to check |
| * the return value. This means zeroing out the destination variable |
| * or buffer on error. Normally this is done out of line by the |
| * fixup code, but there are a few places where it intrudes on the |
| * main code path. When we only write to user space, there is no |
| * problem. |
| * |
| * The "__xxx" versions of the user access functions do not verify the |
| * address space - it must have been done previously with a separate |
| * "access_ok()" call. |
| * |
| * The "xxx_error" versions set the third argument to EFAULT if an |
| * error occurs, and leave it unchanged on success. Note that these |
| * versions are void (ie, don't return a value as such). |
| */ |
| |
| extern int __get_user_1(void *); |
| extern int __get_user_2(void *); |
| extern int __get_user_4(void *); |
| extern int __get_user_bad(void); |
| |
| #define __get_user_x(__r2,__p,__e,__s,__i...) \ |
| __asm__ __volatile__ ( \ |
| __asmeq("%0", "r0") __asmeq("%1", "r2") \ |
| "bl __get_user_" #__s \ |
| : "=&r" (__e), "=r" (__r2) \ |
| : "0" (__p) \ |
| : __i, "cc") |
| |
| #define get_user(x,p) \ |
| ({ \ |
| const register typeof(*(p)) __user *__p asm("r0") = (p);\ |
| register unsigned int __r2 asm("r2"); \ |
| register int __e asm("r0"); \ |
| switch (sizeof(*(__p))) { \ |
| case 1: \ |
| __get_user_x(__r2, __p, __e, 1, "lr"); \ |
| break; \ |
| case 2: \ |
| __get_user_x(__r2, __p, __e, 2, "r3", "lr"); \ |
| break; \ |
| case 4: \ |
| __get_user_x(__r2, __p, __e, 4, "lr"); \ |
| break; \ |
| default: __e = __get_user_bad(); break; \ |
| } \ |
| x = (typeof(*(p))) __r2; \ |
| __e; \ |
| }) |
| |
| #define __get_user(x,ptr) \ |
| ({ \ |
| long __gu_err = 0; \ |
| __get_user_err((x),(ptr),__gu_err); \ |
| __gu_err; \ |
| }) |
| |
| #define __get_user_error(x,ptr,err) \ |
| ({ \ |
| __get_user_err((x),(ptr),err); \ |
| (void) 0; \ |
| }) |
| |
| #define __get_user_err(x,ptr,err) \ |
| do { \ |
| unsigned long __gu_addr = (unsigned long)(ptr); \ |
| unsigned long __gu_val; \ |
| __chk_user_ptr(ptr); \ |
| switch (sizeof(*(ptr))) { \ |
| case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \ |
| case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \ |
| case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \ |
| default: (__gu_val) = __get_user_bad(); \ |
| } \ |
| (x) = (__typeof__(*(ptr)))__gu_val; \ |
| } while (0) |
| |
| #define __get_user_asm_byte(x,addr,err) \ |
| __asm__ __volatile__( \ |
| "1: ldrbt %1,[%2],#0\n" \ |
| "2:\n" \ |
| " .section .fixup,\"ax\"\n" \ |
| " .align 2\n" \ |
| "3: mov %0, %3\n" \ |
| " mov %1, #0\n" \ |
| " b 2b\n" \ |
| " .previous\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .align 3\n" \ |
| " .long 1b, 3b\n" \ |
| " .previous" \ |
| : "+r" (err), "=&r" (x) \ |
| : "r" (addr), "i" (-EFAULT) \ |
| : "cc") |
| |
| #ifndef __ARMEB__ |
| #define __get_user_asm_half(x,__gu_addr,err) \ |
| ({ \ |
| unsigned long __b1, __b2; \ |
| __get_user_asm_byte(__b1, __gu_addr, err); \ |
| __get_user_asm_byte(__b2, __gu_addr + 1, err); \ |
| (x) = __b1 | (__b2 << 8); \ |
| }) |
| #else |
| #define __get_user_asm_half(x,__gu_addr,err) \ |
| ({ \ |
| unsigned long __b1, __b2; \ |
| __get_user_asm_byte(__b1, __gu_addr, err); \ |
| __get_user_asm_byte(__b2, __gu_addr + 1, err); \ |
| (x) = (__b1 << 8) | __b2; \ |
| }) |
| #endif |
| |
| #define __get_user_asm_word(x,addr,err) \ |
| __asm__ __volatile__( \ |
| "1: ldrt %1,[%2],#0\n" \ |
| "2:\n" \ |
| " .section .fixup,\"ax\"\n" \ |
| " .align 2\n" \ |
| "3: mov %0, %3\n" \ |
| " mov %1, #0\n" \ |
| " b 2b\n" \ |
| " .previous\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .align 3\n" \ |
| " .long 1b, 3b\n" \ |
| " .previous" \ |
| : "+r" (err), "=&r" (x) \ |
| : "r" (addr), "i" (-EFAULT) \ |
| : "cc") |
| |
| extern int __put_user_1(void *, unsigned int); |
| extern int __put_user_2(void *, unsigned int); |
| extern int __put_user_4(void *, unsigned int); |
| extern int __put_user_8(void *, unsigned long long); |
| extern int __put_user_bad(void); |
| |
| #define __put_user_x(__r2,__p,__e,__s) \ |
| __asm__ __volatile__ ( \ |
| __asmeq("%0", "r0") __asmeq("%2", "r2") \ |
| "bl __put_user_" #__s \ |
| : "=&r" (__e) \ |
| : "0" (__p), "r" (__r2) \ |
| : "ip", "lr", "cc") |
| |
| #define put_user(x,p) \ |
| ({ \ |
| const register typeof(*(p)) __r2 asm("r2") = (x); \ |
| const register typeof(*(p)) __user *__p asm("r0") = (p);\ |
| register int __e asm("r0"); \ |
| switch (sizeof(*(__p))) { \ |
| case 1: \ |
| __put_user_x(__r2, __p, __e, 1); \ |
| break; \ |
| case 2: \ |
| __put_user_x(__r2, __p, __e, 2); \ |
| break; \ |
| case 4: \ |
| __put_user_x(__r2, __p, __e, 4); \ |
| break; \ |
| case 8: \ |
| __put_user_x(__r2, __p, __e, 8); \ |
| break; \ |
| default: __e = __put_user_bad(); break; \ |
| } \ |
| __e; \ |
| }) |
| |
| #define __put_user(x,ptr) \ |
| ({ \ |
| long __pu_err = 0; \ |
| __put_user_err((x),(ptr),__pu_err); \ |
| __pu_err; \ |
| }) |
| |
| #define __put_user_error(x,ptr,err) \ |
| ({ \ |
| __put_user_err((x),(ptr),err); \ |
| (void) 0; \ |
| }) |
| |
| #define __put_user_err(x,ptr,err) \ |
| do { \ |
| unsigned long __pu_addr = (unsigned long)(ptr); \ |
| __typeof__(*(ptr)) __pu_val = (x); \ |
| __chk_user_ptr(ptr); \ |
| switch (sizeof(*(ptr))) { \ |
| case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \ |
| case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \ |
| case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \ |
| case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \ |
| default: __put_user_bad(); \ |
| } \ |
| } while (0) |
| |
| #define __put_user_asm_byte(x,__pu_addr,err) \ |
| __asm__ __volatile__( \ |
| "1: strbt %1,[%2],#0\n" \ |
| "2:\n" \ |
| " .section .fixup,\"ax\"\n" \ |
| " .align 2\n" \ |
| "3: mov %0, %3\n" \ |
| " b 2b\n" \ |
| " .previous\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .align 3\n" \ |
| " .long 1b, 3b\n" \ |
| " .previous" \ |
| : "+r" (err) \ |
| : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \ |
| : "cc") |
| |
| #ifndef __ARMEB__ |
| #define __put_user_asm_half(x,__pu_addr,err) \ |
| ({ \ |
| unsigned long __temp = (unsigned long)(x); \ |
| __put_user_asm_byte(__temp, __pu_addr, err); \ |
| __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \ |
| }) |
| #else |
| #define __put_user_asm_half(x,__pu_addr,err) \ |
| ({ \ |
| unsigned long __temp = (unsigned long)(x); \ |
| __put_user_asm_byte(__temp >> 8, __pu_addr, err); \ |
| __put_user_asm_byte(__temp, __pu_addr + 1, err); \ |
| }) |
| #endif |
| |
| #define __put_user_asm_word(x,__pu_addr,err) \ |
| __asm__ __volatile__( \ |
| "1: strt %1,[%2],#0\n" \ |
| "2:\n" \ |
| " .section .fixup,\"ax\"\n" \ |
| " .align 2\n" \ |
| "3: mov %0, %3\n" \ |
| " b 2b\n" \ |
| " .previous\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .align 3\n" \ |
| " .long 1b, 3b\n" \ |
| " .previous" \ |
| : "+r" (err) \ |
| : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \ |
| : "cc") |
| |
| #ifndef __ARMEB__ |
| #define __reg_oper0 "%R2" |
| #define __reg_oper1 "%Q2" |
| #else |
| #define __reg_oper0 "%Q2" |
| #define __reg_oper1 "%R2" |
| #endif |
| |
| #define __put_user_asm_dword(x,__pu_addr,err) \ |
| __asm__ __volatile__( \ |
| "1: strt " __reg_oper1 ", [%1], #4\n" \ |
| "2: strt " __reg_oper0 ", [%1], #0\n" \ |
| "3:\n" \ |
| " .section .fixup,\"ax\"\n" \ |
| " .align 2\n" \ |
| "4: mov %0, %3\n" \ |
| " b 3b\n" \ |
| " .previous\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .align 3\n" \ |
| " .long 1b, 4b\n" \ |
| " .long 2b, 4b\n" \ |
| " .previous" \ |
| : "+r" (err), "+r" (__pu_addr) \ |
| : "r" (x), "i" (-EFAULT) \ |
| : "cc") |
| |
| |
| extern unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n); |
| extern unsigned long __copy_to_user(void __user *to, const void *from, unsigned long n); |
| extern unsigned long __clear_user(void __user *addr, unsigned long n); |
| extern unsigned long __strncpy_from_user(char *to, const char __user *from, unsigned long count); |
| extern unsigned long __strnlen_user(const char __user *s, long n); |
| |
| static inline unsigned long copy_from_user(void *to, const void __user *from, unsigned long n) |
| { |
| if (access_ok(VERIFY_READ, from, n)) |
| n = __copy_from_user(to, from, n); |
| else /* security hole - plug it */ |
| memzero(to, n); |
| return n; |
| } |
| |
| static inline unsigned long copy_to_user(void __user *to, const void *from, unsigned long n) |
| { |
| if (access_ok(VERIFY_WRITE, to, n)) |
| n = __copy_to_user(to, from, n); |
| return n; |
| } |
| |
| #define __copy_to_user_inatomic __copy_to_user |
| #define __copy_from_user_inatomic __copy_from_user |
| |
| static inline unsigned long clear_user(void __user *to, unsigned long n) |
| { |
| if (access_ok(VERIFY_WRITE, to, n)) |
| n = __clear_user(to, n); |
| return n; |
| } |
| |
| static inline long strncpy_from_user(char *dst, const char __user *src, long count) |
| { |
| long res = -EFAULT; |
| if (access_ok(VERIFY_READ, src, 1)) |
| res = __strncpy_from_user(dst, src, count); |
| return res; |
| } |
| |
| #define strlen_user(s) strnlen_user(s, ~0UL >> 1) |
| |
| static inline long strnlen_user(const char __user *s, long n) |
| { |
| unsigned long res = 0; |
| |
| if (__addr_ok(s)) |
| res = __strnlen_user(s, n); |
| |
| return res; |
| } |
| |
| #endif /* _ASMARM_UACCESS_H */ |