| /* |
| * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) |
| * Licensed under the GPL |
| */ |
| |
| #ifndef __UM_UACCESS_H |
| #define __UM_UACCESS_H |
| |
| #include "linux/string.h" |
| #include "linux/sched.h" |
| #include "asm/processor.h" |
| #include "asm/errno.h" |
| #include "asm/current.h" |
| #include "asm/a.out.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) }) |
| |
| #define ABOVE_KMEM (16 * 1024 * 1024) |
| |
| #define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) |
| #define USER_DS MAKE_MM_SEG(TASK_SIZE) |
| |
| #define get_ds() (KERNEL_DS) |
| #define get_fs() (current->addr_limit) |
| #define set_fs(x) (current->addr_limit = (x)) |
| |
| extern unsigned long end_vm; |
| extern unsigned long uml_physmem; |
| |
| #define under_task_size(addr, size) \ |
| (((unsigned long) (addr) < TASK_SIZE) && \ |
| (((unsigned long) (addr) + (size)) < TASK_SIZE)) |
| |
| #define is_stack(addr, size) \ |
| (((unsigned long) (addr) < STACK_TOP) && \ |
| ((unsigned long) (addr) >= STACK_TOP - ABOVE_KMEM) && \ |
| (((unsigned long) (addr) + (size)) <= STACK_TOP)) |
| |
| #define segment_eq(a, b) ((a).seg == (b).seg) |
| |
| #define access_ok(type, addr, size) \ |
| ((type == VERIFY_READ) || (segment_eq(get_fs(), KERNEL_DS)) || \ |
| (((unsigned long) (addr) <= ((unsigned long) (addr) + (size))) && \ |
| (under_task_size(addr, size) || is_stack(addr, size)))) |
| |
| static inline int verify_area(int type, const void * addr, unsigned long size) |
| { |
| return(access_ok(type, addr, size) ? 0 : -EFAULT); |
| } |
| |
| extern unsigned long get_fault_addr(void); |
| |
| extern int __do_copy_from_user(void *to, const void *from, int n, |
| void **fault_addr, void **fault_catcher); |
| |
| static inline int copy_from_user(void *to, const void *from, int n) |
| { |
| return(access_ok(VERIFY_READ, from, n) ? |
| __do_copy_from_user(to, from, n, |
| ¤t->thread.fault_addr, |
| ¤t->thread.fault_catcher) : n); |
| } |
| |
| #define __copy_from_user(to, from, n) copy_from_user(to, from, n) |
| |
| extern int __do_copy_to_user(void *to, const void *from, int n, |
| void **fault_addr, void **fault_catcher); |
| |
| static inline int copy_to_user(void *to, const void *from, int n) |
| { |
| return(access_ok(VERIFY_WRITE, to, n) ? |
| __do_copy_from_user(to, from, n, |
| ¤t->thread.fault_addr, |
| ¤t->thread.fault_catcher) : n); |
| } |
| |
| #define __copy_to_user(to, from, n) copy_to_user(to, from, n) |
| |
| #define __get_user(x, ptr) \ |
| ({ \ |
| const __typeof__(ptr) __private_ptr = ptr; \ |
| __typeof__(*(__private_ptr)) __private_val; \ |
| int __private_ret = -EFAULT; \ |
| (x) = 0; \ |
| if (__copy_from_user(&__private_val, (__private_ptr), \ |
| sizeof(*(__private_ptr))) == 0) {\ |
| (x) = (__typeof__(*(__private_ptr))) __private_val; \ |
| __private_ret = 0; \ |
| } \ |
| __private_ret; \ |
| }) |
| |
| #define get_user(x, ptr) \ |
| ({ \ |
| const __typeof__((*ptr)) *private_ptr = (ptr); \ |
| (access_ok(VERIFY_READ, private_ptr, sizeof(*private_ptr)) ? \ |
| __get_user(x, private_ptr) : ((x) = 0, -EFAULT)); \ |
| }) |
| |
| #define __put_user(x, ptr) \ |
| ({ \ |
| __typeof__(ptr) __private_ptr = ptr; \ |
| __typeof__(*(__private_ptr)) __private_val; \ |
| int __private_ret = -EFAULT; \ |
| __private_val = (__typeof__(*(__private_ptr))) (x); \ |
| if (__copy_to_user((__private_ptr), &__private_val, \ |
| sizeof(*(__private_ptr))) == 0) { \ |
| __private_ret = 0; \ |
| } \ |
| __private_ret; \ |
| }) |
| |
| #define put_user(x, ptr) \ |
| ({ \ |
| __typeof__(*(ptr)) *private_ptr = (ptr); \ |
| (access_ok(VERIFY_WRITE, private_ptr, sizeof(*private_ptr)) ? \ |
| __put_user(x, private_ptr) : -EFAULT); \ |
| }) |
| |
| extern int __do_strncpy_from_user(char *dst, const char *src, size_t n, |
| void **fault_addr, void **fault_catcher); |
| |
| static inline int strncpy_from_user(char *dst, const char *src, int count) |
| { |
| int n; |
| |
| if(!access_ok(VERIFY_READ, src, 1)) return(-EFAULT); |
| n = __do_strncpy_from_user(dst, src, count, |
| ¤t->thread.fault_addr, |
| ¤t->thread.fault_catcher); |
| if(n < 0) return(-EFAULT); |
| return(n); |
| } |
| |
| extern int __do_clear_user(void *mem, size_t len, void **fault_addr, |
| void **fault_catcher); |
| |
| static inline int __clear_user(void *mem, int len) |
| { |
| return(__do_clear_user(mem, len, |
| ¤t->thread.fault_addr, |
| ¤t->thread.fault_catcher)); |
| } |
| |
| static inline int clear_user(void *mem, int len) |
| { |
| return(access_ok(VERIFY_WRITE, mem, len) ? |
| __do_clear_user(mem, len, |
| ¤t->thread.fault_addr, |
| ¤t->thread.fault_catcher) : len); |
| } |
| |
| extern int __do_strnlen_user(const char *str, unsigned long n, |
| void **fault_addr, void **fault_catcher); |
| |
| static inline int strnlen_user(void *str, int len) |
| { |
| return(__do_strnlen_user(str, len, |
| ¤t->thread.fault_addr, |
| ¤t->thread.fault_catcher)); |
| } |
| |
| #define strlen_user(str) strnlen_user(str, ~0UL >> 1) |
| |
| struct exception_table_entry |
| { |
| unsigned long insn; |
| unsigned long fixup; |
| }; |
| |
| #endif |
| |
| /* |
| * Overrides for Emacs so that we follow Linus's tabbing style. |
| * Emacs will notice this stuff at the end of the file and automatically |
| * adjust the settings for this buffer only. This must remain at the end |
| * of the file. |
| * --------------------------------------------------------------------------- |
| * Local variables: |
| * c-file-style: "linux" |
| * End: |
| */ |