uaccess.h
来自「Linux Kernel 2.6.9 for OMAP1710」· C头文件 代码 · 共 182 行
H
182 行
#ifndef __M68KNOMMU_UACCESS_H#define __M68KNOMMU_UACCESS_H/* * User space memory access functions */#include <linux/sched.h>#include <linux/mm.h>#include <linux/string.h>#include <asm/segment.h>#define VERIFY_READ 0#define VERIFY_WRITE 1#define access_ok(type,addr,size) _access_ok((unsigned long)(addr),(size))static inline int _access_ok(unsigned long addr, unsigned long size){ extern unsigned long memory_start, memory_end; return (((addr >= memory_start) && (addr+size < memory_end)) || (is_in_rom(addr) && is_in_rom(addr+size)));}extern inline int verify_area(int type, const void * addr, unsigned long size){ return access_ok(type,addr,size)?0:-EFAULT;}/* * 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;};/* Returns 0 if exception not found and fixup otherwise. */extern unsigned long search_exception_table(unsigned long);/* * These are the main single-value transfer routines. They automatically * use the right size if we just have the right pointer type. */#define put_user(x, ptr) \({ \ int __pu_err = 0; \ typeof(*(ptr)) __pu_val = (x); \ switch (sizeof (*(ptr))) { \ case 1: \ __put_user_asm(__pu_err, __pu_val, ptr, b); \ break; \ case 2: \ __put_user_asm(__pu_err, __pu_val, ptr, w); \ break; \ case 4: \ __put_user_asm(__pu_err, __pu_val, ptr, l); \ break; \ case 8: \ memcpy(ptr, &__pu_val, sizeof (*(ptr))); \ break; \ default: \ __pu_err = __put_user_bad(); \ break; \ } \ __pu_err; \})#define __put_user(x, ptr) put_user(x, ptr)extern int __put_user_bad(void);/* * 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 __ptr(x) ((unsigned long *)(x))#define __put_user_asm(err,x,ptr,bwl) \ __asm__ ("move" #bwl " %0,%1" \ : /* no outputs */ \ :"d" (x),"m" (*__ptr(ptr)) : "memory")#define get_user(x, ptr) \({ \ int __gu_err = 0; \ typeof(*(ptr)) __gu_val = 0; \ switch (sizeof(*(ptr))) { \ case 1: \ __get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \ break; \ case 2: \ __get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \ break; \ case 4: \ __get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \ break; \ case 8: \ memcpy(&__gu_val, ptr, sizeof (*(ptr))); \ break; \ default: \ __gu_val = 0; \ __gu_err = __get_user_bad(); \ break; \ } \ (x) = __gu_val; \ __gu_err; \})#define __get_user(x, ptr) get_user(x, ptr)extern int __get_user_bad(void);#define __get_user_asm(err,x,ptr,bwl,reg) \ __asm__ ("move" #bwl " %1,%0" \ : "=d" (x) \ : "m" (*__ptr(ptr)))#define copy_from_user(to, from, n) (memcpy(to, from, n), 0)#define copy_to_user(to, from, n) (memcpy(to, from, n), 0)#define __copy_from_user(to, from, n) copy_from_user(to, from, n)#define __copy_to_user(to, from, n) copy_to_user(to, from, n)#define __copy_to_user_inatomic __copy_to_user#define __copy_from_user_inatomic __copy_from_user#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; })#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; })/* * Copy a null terminated string from userspace. */static inline longstrncpy_from_user(char *dst, const char *src, long count){ char *tmp; strncpy(dst, src, count); for (tmp = dst; *tmp && count > 0; tmp++, count--) ; return(tmp - dst); /* DAVIDM should we count a NUL ? check getname */}/* * Return the size of a string (including the ending 0) * * Return 0 on exception, a value greater than N if too long */static inline long strnlen_user(const char *src, long n){ return(strlen(src) + 1); /* DAVIDM make safer */}#define strlen_user(str) strnlen_user(str, 32767)/* * Zero Userspace */static inline unsigned longclear_user(void *to, unsigned long n){ memset(to, 0, n); return 0;}#endif /* _M68KNOMMU_UACCESS_H */⌨️ 快捷键说明
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