/* $Id: uaccess.h,v 1.35 2002/02/09 19:49:31 davem Exp $ */ #ifndef _ASM_UACCESS_H #define _ASM_UACCESS_H /* * User space memory access functions */ #ifdef __KERNEL__ #include <linux/compiler.h> #include <linux/sched.h> #include <linux/string.h> #include <asm/a.out.h> #include <asm/asi.h> #include <asm/system.h> #include <asm/spitfire.h> #include <asm-generic/uaccess.h> #endif #ifndef __ASSEMBLY__ /* * Sparc64 is segmented, though more like the M68K than the I386. * We use the secondary ASI to address user memory, which references a * completely different VM map, thus there is zero chance of the user * doing something queer and tricking us into poking kernel memory. * * What is left here is basically what is needed for the other parts of * the kernel that expect to be able to manipulate, erum, "segments". * Or perhaps more properly, permissions. * * "For historical reasons, these macros are grossly misnamed." -Linus */ #define KERNEL_DS ((mm_segment_t) { ASI_P }) #define USER_DS ((mm_segment_t) { ASI_AIUS }) /* har har har */ #define VERIFY_READ 0 #define VERIFY_WRITE 1 #define get_fs() ((mm_segment_t) { get_thread_current_ds() }) #define get_ds() (KERNEL_DS) #define segment_eq(a,b) ((a).seg == (b).seg) #define set_fs(val) \ do { \ set_thread_current_ds((val).seg); \ __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \ } while(0) static inline int __access_ok(const void __user * addr, unsigned long size) { return 1; } static inline int access_ok(int type, const void __user * addr, unsigned long size) { return 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 int insn, fixup; }; extern void __ret_efault(void); extern void __retl_efault(void); /* Uh, these should become 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 ugliness from the user. */ #define put_user(x,ptr) ({ \ unsigned long __pu_addr = (unsigned long)(ptr); \ __chk_user_ptr(ptr); \ __put_user_nocheck((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); }) #define get_user(x,ptr) ({ \ unsigned long __gu_addr = (unsigned long)(ptr); \ __chk_user_ptr(ptr); \ __get_user_nocheck((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); }) #define __put_user(x,ptr) put_user(x,ptr) #define __get_user(x,ptr) get_user(x,ptr) struct __large_struct { unsigned long buf[100]; }; #define __m(x) ((struct __large_struct *)(x)) #define __put_user_nocheck(data,addr,size) ({ \ register int __pu_ret; \ switch (size) { \ case 1: __put_user_asm(data,b,addr,__pu_ret); break; \ case 2: __put_user_asm(data,h,addr,__pu_ret); break; \ case 4: __put_user_asm(data,w,addr,__pu_ret); break; \ case 8: __put_user_asm(data,x,addr,__pu_ret); break; \ default: __pu_ret = __put_user_bad(); break; \ } __pu_ret; }) #define __put_user_asm(x,size,addr,ret) \ __asm__ __volatile__( \ "/* Put user asm, inline. */\n" \ "1:\t" "st"#size "a %1, [%2] %%asi\n\t" \ "clr %0\n" \ "2:\n\n\t" \ ".section .fixup,#alloc,#execinstr\n\t" \ ".align 4\n" \ "3:\n\t" \ "b 2b\n\t" \ " mov %3, %0\n\n\t" \ ".previous\n\t" \ ".section __ex_table,\"a\"\n\t" \ ".align 4\n\t" \ ".word 1b, 3b\n\t" \ ".previous\n\n\t" \ : "=r" (ret) : "r" (x), "r" (__m(addr)), \ "i" (-EFAULT)) extern int __put_user_bad(void); #define __get_user_nocheck(data,addr,size,type) ({ \ register int __gu_ret; \ register unsigned long __gu_val; \ switch (size) { \ case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \ case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \ case 4: __get_user_asm(__gu_val,uw,addr,__gu_ret); break; \ case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \ default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \ } data = (type) __gu_val; __gu_ret; }) #define __get_user_nocheck_ret(data,addr,size,type,retval) ({ \ register unsigned long __gu_val __asm__ ("l1"); \ switch (size) { \ case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \ case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \ case 4: __get_user_asm_ret(__gu_val,uw,addr,retval); break; \ case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \ default: if (__get_user_bad()) return retval; \ } data = (type) __gu_val; }) #define __get_user_asm(x,size,addr,ret) \ __asm__ __volatile__( \ "/* Get user asm, inline. */\n" \ "1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \ "clr %0\n" \ "2:\n\n\t" \ ".section .fixup,#alloc,#execinstr\n\t" \ ".align 4\n" \ "3:\n\t" \ "clr %1\n\t" \ "b 2b\n\t" \ " mov %3, %0\n\n\t" \ ".previous\n\t" \ ".section __ex_table,\"a\"\n\t" \ ".align 4\n\t" \ ".word 1b, 3b\n\n\t" \ ".previous\n\t" \ : "=r" (ret), "=r" (x) : "r" (__m(addr)), \ "i" (-EFAULT)) #define __get_user_asm_ret(x,size,addr,retval) \ if (__builtin_constant_p(retval) && retval == -EFAULT) \ __asm__ __volatile__( \ "/* Get user asm ret, inline. */\n" \ "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ ".section __ex_table,\"a\"\n\t" \ ".align 4\n\t" \ ".word 1b,__ret_efault\n\n\t" \ ".previous\n\t" \ : "=r" (x) : "r" (__m(addr))); \ else \ __asm__ __volatile__( \ "/* Get user asm ret, inline. */\n" \ "1:\t" "ld"#size "a [%1] %%asi, %0\n\n\t" \ ".section .fixup,#alloc,#execinstr\n\t" \ ".align 4\n" \ "3:\n\t" \ "ret\n\t" \ " restore %%g0, %2, %%o0\n\n\t" \ ".previous\n\t" \ ".section __ex_table,\"a\"\n\t" \ ".align 4\n\t" \ ".word 1b, 3b\n\n\t" \ ".previous\n\t" \ : "=r" (x) : "r" (__m(addr)), "i" (retval)) extern int __get_user_bad(void); extern unsigned long __must_check ___copy_from_user(void *to, const void __user *from, unsigned long size); extern unsigned long copy_from_user_fixup(void *to, const void __user *from, unsigned long size); static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long size) { unsigned long ret = ___copy_from_user(to, from, size); if (unlikely(ret)) ret = copy_from_user_fixup(to, from, size); return ret; } #define __copy_from_user copy_from_user extern unsigned long __must_check ___copy_to_user(void __user *to, const void *from, unsigned long size); extern unsigned long copy_to_user_fixup(void __user *to, const void *from, unsigned long size); static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long size) { unsigned long ret = ___copy_to_user(to, from, size); if (unlikely(ret)) ret = copy_to_user_fixup(to, from, size); return ret; } #define __copy_to_user copy_to_user extern unsigned long __must_check ___copy_in_user(void __user *to, const void __user *from, unsigned long size); extern unsigned long copy_in_user_fixup(void __user *to, void __user *from, unsigned long size); static inline unsigned long __must_check copy_in_user(void __user *to, void __user *from, unsigned long size) { unsigned long ret = ___copy_in_user(to, from, size); if (unlikely(ret)) ret = copy_in_user_fixup(to, from, size); return ret; } #define __copy_in_user copy_in_user extern unsigned long __must_check __clear_user(void __user *, unsigned long); #define clear_user __clear_user extern long __must_check __strncpy_from_user(char *dest, const char __user *src, long count); #define strncpy_from_user __strncpy_from_user extern long __strlen_user(const char __user *); extern long __strnlen_user(const char __user *, long len); #define strlen_user __strlen_user #define strnlen_user __strnlen_user #define __copy_to_user_inatomic __copy_to_user #define __copy_from_user_inatomic __copy_from_user #endif /* __ASSEMBLY__ */ #endif /* _ASM_UACCESS_H */