diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-sh/uaccess.h | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-sh/uaccess.h')
-rw-r--r-- | include/asm-sh/uaccess.h | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/include/asm-sh/uaccess.h b/include/asm-sh/uaccess.h new file mode 100644 index 000000000000..fb9e334afa2b --- /dev/null +++ b/include/asm-sh/uaccess.h @@ -0,0 +1,600 @@ +/* $Id: uaccess.h,v 1.11 2003/10/13 07:21:20 lethal Exp $ + * + * User space memory access functions + * + * Copyright (C) 1999, 2002 Niibe Yutaka + * Copyright (C) 2003 Paul Mundt + * + * Based on: + * MIPS implementation version 1.15 by + * Copyright (C) 1996, 1997, 1998 by Ralf Baechle + * and i386 version. + */ +#ifndef __ASM_SH_UACCESS_H +#define __ASM_SH_UACCESS_H + +#include <linux/errno.h> +#include <linux/sched.h> + +/* + * NOTE: Macro/functions in this file depends on threads_info.h implementation. + * Assumes: + * TI_FLAGS == 8 + * TIF_USERSPACE == 31 + * USER_ADDR_LIMIT == 0x80000000 + */ + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +typedef struct { + unsigned int is_user_space; +} mm_segment_t; + +/* + * 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 (Data Segment Register?), these macros are misnamed. + */ + +#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) +#define segment_eq(a,b) ((a).is_user_space == (b).is_user_space) + +#define USER_ADDR_LIMIT 0x80000000 + +#define KERNEL_DS MAKE_MM_SEG(0) +#define USER_DS MAKE_MM_SEG(1) + +#define get_ds() (KERNEL_DS) + +#if !defined(CONFIG_MMU) +static inline mm_segment_t get_fs(void) +{ + return USER_DS; +} + +static inline void set_fs(mm_segment_t s) +{ +} + +/* + * __access_ok: Check if address with size is OK or not. + * + * If we don't have an MMU (or if its disabled) the only thing we really have + * to look out for is if the address resides somewhere outside of what + * available RAM we have. + * + * TODO: This check could probably also stand to be restricted somewhat more.. + * though it still does the Right Thing(tm) for the time being. + */ +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)); +} +#else /* CONFIG_MMU */ +static inline mm_segment_t get_fs(void) +{ + return MAKE_MM_SEG(test_thread_flag(TIF_USERSPACE)); +} + +static inline void set_fs(mm_segment_t s) +{ + unsigned long ti, flag; + __asm__ __volatile__( + "stc r7_bank, %0\n\t" + "mov.l @(8,%0), %1\n\t" + "shal %1\n\t" + "cmp/pl %2\n\t" + "rotcr %1\n\t" + "mov.l %1, @(8,%0)" + : "=&r" (ti), "=&r" (flag) + : "r" (s.is_user_space) + : "t"); +/**** + if (s.is_user_space) + set_thread_flag(TIF_USERSPACE); + else + clear_thread_flag(TIF_USERSPACE); +****/ +} + +/* + * __access_ok: Check if address with size is OK or not. + * + * We do three checks: + * (1) is it user space? + * (2) addr + size --> carry? + * (3) addr + size >= 0x80000000 (USER_ADDR_LIMIT) + * + * (1) (2) (3) | RESULT + * 0 0 0 | ok + * 0 0 1 | ok + * 0 1 0 | bad + * 0 1 1 | bad + * 1 0 0 | ok + * 1 0 1 | bad + * 1 1 0 | bad + * 1 1 1 | bad + */ +static inline int __access_ok(unsigned long addr, unsigned long size) +{ + unsigned long flag, tmp; + + __asm__("stc r7_bank, %0\n\t" + "mov.l @(8,%0), %0\n\t" + "clrt\n\t" + "addc %2, %1\n\t" + "and %1, %0\n\t" + "rotcl %0\n\t" + "rotcl %0\n\t" + "and #3, %0" + : "=&z" (flag), "=r" (tmp) + : "r" (addr), "1" (size) + : "t"); + + return flag == 0; +} +#endif /* CONFIG_MMU */ + +static inline int access_ok(int type, const void __user *p, unsigned long size) +{ + unsigned long addr = (unsigned long)p; + return __access_ok(addr, size); +} + +/* this function will go away soon - use access_ok() instead */ +static inline int __deprecated verify_area(int type, const void __user * addr, unsigned long size) +{ + return access_ok(type,addr,size) ? 0 : -EFAULT; +} + +/* + * Uh, these should become the main single-value transfer routines ... + * They automatically use the right size if we just have the right + * pointer type ... + * + * As SuperH uses the same address space for kernel and user data, we + * can just do these as direct assignments. + * + * Careful to not + * (a) re-use the arguments for side effects (sizeof is ok) + * (b) require any knowledge of processes at this stage + */ +#define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr))) +#define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr))) + +/* + * The "__xxx" versions do not do address space checking, useful when + * doing multiple accesses to the same area (the user has to do the + * checks by hand with "access_ok()") + */ +#define __put_user(x,ptr) \ + __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr))) +#define __get_user(x,ptr) \ + __get_user_nocheck((x),(ptr),sizeof(*(ptr))) + +struct __large_struct { unsigned long buf[100]; }; +#define __m(x) (*(struct __large_struct *)(x)) + +#define __get_user_size(x,ptr,size,retval) \ +do { \ + retval = 0; \ + switch (size) { \ + case 1: \ + __get_user_asm(x, ptr, retval, "b"); \ + break; \ + case 2: \ + __get_user_asm(x, ptr, retval, "w"); \ + break; \ + case 4: \ + __get_user_asm(x, ptr, retval, "l"); \ + break; \ + default: \ + __get_user_unknown(); \ + break; \ + } \ +} while (0) + +#define __get_user_nocheck(x,ptr,size) \ +({ \ + long __gu_err, __gu_val; \ + __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, __gu_val; \ + switch (size) { \ + case 1: \ + __get_user_1(__gu_val, (ptr), __gu_err); \ + break; \ + case 2: \ + __get_user_2(__gu_val, (ptr), __gu_err); \ + break; \ + case 4: \ + __get_user_4(__gu_val, (ptr), __gu_err); \ + break; \ + default: \ + __get_user_unknown(); \ + break; \ + } \ + \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +#define __get_user_1(x,addr,err) ({ \ +__asm__("stc r7_bank, %1\n\t" \ + "mov.l @(8,%1), %1\n\t" \ + "and %2, %1\n\t" \ + "cmp/pz %1\n\t" \ + "bt/s 1f\n\t" \ + " mov #0, %0\n\t" \ + "0:\n" \ + "mov #-14, %0\n\t" \ + "bra 2f\n\t" \ + " mov #0, %1\n" \ + "1:\n\t" \ + "mov.b @%2, %1\n\t" \ + "extu.b %1, %1\n" \ + "2:\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 0b\n\t" \ + ".previous" \ + : "=&r" (err), "=&r" (x) \ + : "r" (addr) \ + : "t"); \ +}) + +#define __get_user_2(x,addr,err) ({ \ +__asm__("stc r7_bank, %1\n\t" \ + "mov.l @(8,%1), %1\n\t" \ + "and %2, %1\n\t" \ + "cmp/pz %1\n\t" \ + "bt/s 1f\n\t" \ + " mov #0, %0\n\t" \ + "0:\n" \ + "mov #-14, %0\n\t" \ + "bra 2f\n\t" \ + " mov #0, %1\n" \ + "1:\n\t" \ + "mov.w @%2, %1\n\t" \ + "extu.w %1, %1\n" \ + "2:\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 0b\n\t" \ + ".previous" \ + : "=&r" (err), "=&r" (x) \ + : "r" (addr) \ + : "t"); \ +}) + +#define __get_user_4(x,addr,err) ({ \ +__asm__("stc r7_bank, %1\n\t" \ + "mov.l @(8,%1), %1\n\t" \ + "and %2, %1\n\t" \ + "cmp/pz %1\n\t" \ + "bt/s 1f\n\t" \ + " mov #0, %0\n\t" \ + "0:\n" \ + "mov #-14, %0\n\t" \ + "bra 2f\n\t" \ + " mov #0, %1\n" \ + "1:\n\t" \ + "mov.l @%2, %1\n\t" \ + "2:\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 0b\n\t" \ + ".previous" \ + : "=&r" (err), "=&r" (x) \ + : "r" (addr) \ + : "t"); \ +}) + +#define __get_user_asm(x, addr, err, insn) \ +({ \ +__asm__ __volatile__( \ + "1:\n\t" \ + "mov." insn " %2, %1\n\t" \ + "mov #0, %0\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3:\n\t" \ + "mov #0, %1\n\t" \ + "mov.l 4f, %0\n\t" \ + "jmp @%0\n\t" \ + " mov %3, %0\n" \ + "4: .long 2b\n\t" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 3b\n\t" \ + ".previous" \ + :"=&r" (err), "=&r" (x) \ + :"m" (__m(addr)), "i" (-EFAULT)); }) + +extern void __get_user_unknown(void); + +#define __put_user_size(x,ptr,size,retval) \ +do { \ + retval = 0; \ + switch (size) { \ + case 1: \ + __put_user_asm(x, ptr, retval, "b"); \ + break; \ + case 2: \ + __put_user_asm(x, ptr, retval, "w"); \ + break; \ + case 4: \ + __put_user_asm(x, ptr, retval, "l"); \ + break; \ + case 8: \ + __put_user_u64(x, ptr, retval); \ + break; \ + default: \ + __put_user_unknown(); \ + } \ +} while (0) + +#define __put_user_nocheck(x,ptr,size) \ +({ \ + long __pu_err; \ + __put_user_size((x),(ptr),(size),__pu_err); \ + __pu_err; \ +}) + +#define __put_user_check(x,ptr,size) \ +({ \ + long __pu_err = -EFAULT; \ + __typeof__(*(ptr)) *__pu_addr = (ptr); \ + \ + if (__access_ok((unsigned long)__pu_addr,size)) \ + __put_user_size((x),__pu_addr,(size),__pu_err); \ + __pu_err; \ +}) + +#define __put_user_asm(x, addr, err, insn) \ +({ \ +__asm__ __volatile__( \ + "1:\n\t" \ + "mov." insn " %1, %2\n\t" \ + "mov #0, %0\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3:\n\t" \ + "nop\n\t" \ + "mov.l 4f, %0\n\t" \ + "jmp @%0\n\t" \ + "mov %3, %0\n" \ + "4: .long 2b\n\t" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 3b\n\t" \ + ".previous" \ + :"=&r" (err) \ + :"r" (x), "m" (__m(addr)), "i" (-EFAULT) \ + :"memory"); }) + +#if defined(__LITTLE_ENDIAN__) +#define __put_user_u64(val,addr,retval) \ +({ \ +__asm__ __volatile__( \ + "1:\n\t" \ + "mov.l %R1,%2\n\t" \ + "mov.l %S1,%T2\n\t" \ + "mov #0,%0\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3:\n\t" \ + "nop\n\t" \ + "mov.l 4f,%0\n\t" \ + "jmp @%0\n\t" \ + " mov %3,%0\n" \ + "4: .long 2b\n\t" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 3b\n\t" \ + ".previous" \ + : "=r" (retval) \ + : "r" (val), "m" (__m(addr)), "i" (-EFAULT) \ + : "memory"); }) +#else +#define __put_user_u64(val,addr,retval) \ +({ \ +__asm__ __volatile__( \ + "1:\n\t" \ + "mov.l %S1,%2\n\t" \ + "mov.l %R1,%T2\n\t" \ + "mov #0,%0\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3:\n\t" \ + "nop\n\t" \ + "mov.l 4f,%0\n\t" \ + "jmp @%0\n\t" \ + " mov %3,%0\n" \ + "4: .long 2b\n\t" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".long 1b, 3b\n\t" \ + ".previous" \ + : "=r" (retval) \ + : "r" (val), "m" (__m(addr)), "i" (-EFAULT) \ + : "memory"); }) +#endif + +extern void __put_user_unknown(void); + +/* Generic arbitrary sized copy. */ +/* Return the number of bytes NOT copied */ +extern __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n); + +#define copy_to_user(to,from,n) ({ \ +void *__copy_to = (void *) (to); \ +__kernel_size_t __copy_size = (__kernel_size_t) (n); \ +__kernel_size_t __copy_res; \ +if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \ +__copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \ +} else __copy_res = __copy_size; \ +__copy_res; }) + +#define __copy_to_user(to,from,n) \ + __copy_user((void *)(to), \ + (void *)(from), n) + +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user + + +#define copy_from_user(to,from,n) ({ \ +void *__copy_to = (void *) (to); \ +void *__copy_from = (void *) (from); \ +__kernel_size_t __copy_size = (__kernel_size_t) (n); \ +__kernel_size_t __copy_res; \ +if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \ +__copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \ +} else __copy_res = __copy_size; \ +__copy_res; }) + +#define __copy_from_user(to,from,n) \ + __copy_user((void *)(to), \ + (void *)(from), n) + +/* + * Clear the area and return remaining number of bytes + * (on failure. Usually it's 0.) + */ +extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size); + +#define clear_user(addr,n) ({ \ +void * __cl_addr = (addr); \ +unsigned long __cl_size = (n); \ +if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \ +__cl_size = __clear_user(__cl_addr, __cl_size); \ +__cl_size; }) + +static __inline__ int +__strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __count) +{ + __kernel_size_t res; + unsigned long __dummy, _d, _s; + + __asm__ __volatile__( + "9:\n" + "mov.b @%2+, %1\n\t" + "cmp/eq #0, %1\n\t" + "bt/s 2f\n" + "1:\n" + "mov.b %1, @%3\n\t" + "dt %7\n\t" + "bf/s 9b\n\t" + " add #1, %3\n\t" + "2:\n\t" + "sub %7, %0\n" + "3:\n" + ".section .fixup,\"ax\"\n" + "4:\n\t" + "mov.l 5f, %1\n\t" + "jmp @%1\n\t" + " mov %8, %0\n\t" + ".balign 4\n" + "5: .long 3b\n" + ".previous\n" + ".section __ex_table,\"a\"\n" + " .balign 4\n" + " .long 9b,4b\n" + ".previous" + : "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d) + : "0" (__count), "2" (__src), "3" (__dest), "r" (__count), + "i" (-EFAULT) + : "memory", "t"); + + return res; +} + +#define strncpy_from_user(dest,src,count) ({ \ +unsigned long __sfu_src = (unsigned long) (src); \ +int __sfu_count = (int) (count); \ +long __sfu_res = -EFAULT; \ +if(__access_ok(__sfu_src, __sfu_count)) { \ +__sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \ +} __sfu_res; }) + +/* + * Return the size of a string (including the ending 0!) + */ +static __inline__ long __strnlen_user(const char __user *__s, long __n) +{ + unsigned long res; + unsigned long __dummy; + + __asm__ __volatile__( + "9:\n" + "cmp/eq %4, %0\n\t" + "bt 2f\n" + "1:\t" + "mov.b @(%0,%3), %1\n\t" + "tst %1, %1\n\t" + "bf/s 9b\n\t" + " add #1, %0\n" + "2:\n" + ".section .fixup,\"ax\"\n" + "3:\n\t" + "mov.l 4f, %1\n\t" + "jmp @%1\n\t" + " mov %5, %0\n" + ".balign 4\n" + "4: .long 2b\n" + ".previous\n" + ".section __ex_table,\"a\"\n" + " .balign 4\n" + " .long 1b,3b\n" + ".previous" + : "=z" (res), "=&r" (__dummy) + : "0" (0), "r" (__s), "r" (__n), "i" (-EFAULT) + : "t"); + return res; +} + +static __inline__ long strnlen_user(const char __user *s, long n) +{ + if (!access_ok(VERIFY_READ, s, n)) + return 0; + else + return __strnlen_user(s, n); +} + +static __inline__ long strlen_user(const char __user *s) +{ + if (!access_ok(VERIFY_READ, s, 0)) + return 0; + else + return __strnlen_user(s, ~0UL >> 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); + +#endif /* __ASM_SH_UACCESS_H */ |