diff options
Diffstat (limited to 'arch/microblaze/include/asm/uaccess.h')
| -rw-r--r-- | arch/microblaze/include/asm/uaccess.h | 447 |
1 files changed, 244 insertions, 203 deletions
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 371bd6e56d9..446bec29b14 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -22,101 +22,73 @@ #include <asm/mmu.h> #include <asm/page.h> #include <asm/pgtable.h> -#include <asm/segment.h> #include <linux/string.h> #define VERIFY_READ 0 #define VERIFY_WRITE 1 -#define __clear_user(addr, n) (memset((void *)(addr), 0, (n)), 0) - -#ifndef CONFIG_MMU - -extern int ___range_ok(unsigned long addr, unsigned long size); - -#define __range_ok(addr, size) \ - ___range_ok((unsigned long)(addr), (unsigned long)(size)) - -#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0) -#define __access_ok(add, size) (__range_ok((addr), (size)) == 0) - -/* Undefined function to trigger linker error */ -extern int bad_user_access_length(void); - -/* FIXME this is function for optimalization -> memcpy */ -#define __get_user(var, ptr) \ -({ \ - int __gu_err = 0; \ - switch (sizeof(*(ptr))) { \ - case 1: \ - case 2: \ - case 4: \ - (var) = *(ptr); \ - break; \ - case 8: \ - memcpy((void *) &(var), (ptr), 8); \ - break; \ - default: \ - (var) = 0; \ - __gu_err = __get_user_bad(); \ - break; \ - } \ - __gu_err; \ -}) +/* + * On Microblaze the fs value is actually the top of the corresponding + * address space. + * + * 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. + * + * For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal. + */ +# define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) -#define __get_user_bad() (bad_user_access_length(), (-EFAULT)) +# ifndef CONFIG_MMU +# define KERNEL_DS MAKE_MM_SEG(0) +# define USER_DS KERNEL_DS +# else +# define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) +# define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) +# endif -/* FIXME is not there defined __pu_val */ -#define __put_user(var, ptr) \ -({ \ - int __pu_err = 0; \ - switch (sizeof(*(ptr))) { \ - case 1: \ - case 2: \ - case 4: \ - *(ptr) = (var); \ - break; \ - case 8: { \ - typeof(*(ptr)) __pu_val = (var); \ - memcpy(ptr, &__pu_val, sizeof(__pu_val)); \ - } \ - break; \ - default: \ - __pu_err = __put_user_bad(); \ - break; \ - } \ - __pu_err; \ -}) +# define get_ds() (KERNEL_DS) +# define get_fs() (current_thread_info()->addr_limit) +# define set_fs(val) (current_thread_info()->addr_limit = (val)) -#define __put_user_bad() (bad_user_access_length(), (-EFAULT)) +# define segment_eq(a, b) ((a).seg == (b).seg) -#define put_user(x, ptr) __put_user((x), (ptr)) -#define get_user(x, ptr) __get_user((x), (ptr)) +/* + * 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; +}; -#define copy_to_user(to, from, n) (memcpy((to), (from), (n)), 0) -#define copy_from_user(to, from, n) (memcpy((to), (from), (n)), 0) +/* Returns 0 if exception not found and fixup otherwise. */ +extern unsigned long search_exception_table(unsigned long); -#define __copy_to_user(to, from, n) (copy_to_user((to), (from), (n))) -#define __copy_from_user(to, from, n) (copy_from_user((to), (from), (n))) -#define __copy_to_user_inatomic(to, from, n) \ - (__copy_to_user((to), (from), (n))) -#define __copy_from_user_inatomic(to, from, n) \ - (__copy_from_user((to), (from), (n))) +#ifndef CONFIG_MMU -static inline unsigned long clear_user(void *addr, unsigned long size) +/* Check against bounds of physical memory */ +static inline int ___range_ok(unsigned long addr, unsigned long size) { - if (access_ok(VERIFY_WRITE, addr, size)) - size = __clear_user(addr, size); - return size; + return ((addr < memory_start) || + ((addr + size) > memory_end)); } -/* Returns 0 if exception not found and fixup otherwise. */ -extern unsigned long search_exception_table(unsigned long); +#define __range_ok(addr, size) \ + ___range_ok((unsigned long)(addr), (unsigned long)(size)) -extern long strncpy_from_user(char *dst, const char *src, long count); -extern long strnlen_user(const char *src, long count); +#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0) -#else /* CONFIG_MMU */ +#else /* * Address is valid if: @@ -129,24 +101,88 @@ extern long strnlen_user(const char *src, long count); /* || printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n", type?"WRITE":"READ",addr,size,get_fs().seg)) */ -/* - * All the __XXX versions macros/functions below do not perform - * access checking. It is assumed that the necessary checks have been - * already performed before the finction (macro) is called. - */ +#endif -#define get_user(x, ptr) \ -({ \ - access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \ - ? __get_user((x), (ptr)) : -EFAULT; \ -}) +#ifdef CONFIG_MMU +# define __FIXUP_SECTION ".section .fixup,\"ax\"\n" +# define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n" +#else +# define __FIXUP_SECTION ".section .discard,\"ax\"\n" +# define __EX_TABLE_SECTION ".section .discard,\"a\"\n" +#endif -#define put_user(x, ptr) \ -({ \ - access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) \ - ? __put_user((x), (ptr)) : -EFAULT; \ +extern unsigned long __copy_tofrom_user(void __user *to, + const void __user *from, unsigned long size); + +/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */ +static inline unsigned long __must_check __clear_user(void __user *to, + unsigned long n) +{ + /* normal memset with two words to __ex_table */ + __asm__ __volatile__ ( \ + "1: sb r0, %2, r0;" \ + " addik %0, %0, -1;" \ + " bneid %0, 1b;" \ + " addik %2, %2, 1;" \ + "2: " \ + __EX_TABLE_SECTION \ + ".word 1b,2b;" \ + ".previous;" \ + : "=r"(n) \ + : "0"(n), "r"(to) + ); + return n; +} + +static inline unsigned long __must_check clear_user(void __user *to, + unsigned long n) +{ + might_sleep(); + if (unlikely(!access_ok(VERIFY_WRITE, to, n))) + return n; + + return __clear_user(to, n); +} + +/* put_user and get_user macros */ +extern long __user_bad(void); + +#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ +({ \ + __asm__ __volatile__ ( \ + "1:" insn " %1, %2, r0;" \ + " addk %0, r0, r0;" \ + "2: " \ + __FIXUP_SECTION \ + "3: brid 2b;" \ + " addik %0, r0, %3;" \ + ".previous;" \ + __EX_TABLE_SECTION \ + ".word 1b,3b;" \ + ".previous;" \ + : "=&r"(__gu_err), "=r"(__gu_val) \ + : "r"(__gu_ptr), "i"(-EFAULT) \ + ); \ }) +/** + * get_user: - Get a simple variable from user space. + * @x: Variable to store result. + * @ptr: Source address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple variable from user space to kernel + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and the result of + * dereferencing @ptr must be assignable to @x without a cast. + * + * Returns zero on success, or -EFAULT on error. + * On error, the variable @x is set to zero. + */ + #define __get_user(x, ptr) \ ({ \ unsigned long __gu_val; \ @@ -163,30 +199,74 @@ extern long strnlen_user(const char *src, long count); __get_user_asm("lw", (ptr), __gu_val, __gu_err); \ break; \ default: \ - __gu_val = 0; __gu_err = -EINVAL; \ + /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\ } \ x = (__typeof__(*(ptr))) __gu_val; \ __gu_err; \ }) -#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ + +#define get_user(x, ptr) \ ({ \ - __asm__ __volatile__ ( \ - "1:" insn " %1, %2, r0; \ - addk %0, r0, r0; \ - 2: \ - .section .fixup,\"ax\"; \ - 3: brid 2b; \ - addik %0, r0, %3; \ - .previous; \ - .section __ex_table,\"a\"; \ - .word 1b,3b; \ - .previous;" \ - : "=r"(__gu_err), "=r"(__gu_val) \ - : "r"(__gu_ptr), "i"(-EFAULT) \ - ); \ + access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \ + ? __get_user((x), (ptr)) : -EFAULT; \ +}) + +#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ +({ \ + __asm__ __volatile__ ( \ + "1:" insn " %1, %2, r0;" \ + " addk %0, r0, r0;" \ + "2: " \ + __FIXUP_SECTION \ + "3: brid 2b;" \ + " addik %0, r0, %3;" \ + ".previous;" \ + __EX_TABLE_SECTION \ + ".word 1b,3b;" \ + ".previous;" \ + : "=&r"(__gu_err) \ + : "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \ + ); \ }) +#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \ +({ \ + __asm__ __volatile__ (" lwi %0, %1, 0;" \ + "1: swi %0, %2, 0;" \ + " lwi %0, %1, 4;" \ + "2: swi %0, %2, 4;" \ + " addk %0, r0, r0;" \ + "3: " \ + __FIXUP_SECTION \ + "4: brid 3b;" \ + " addik %0, r0, %3;" \ + ".previous;" \ + __EX_TABLE_SECTION \ + ".word 1b,4b,2b,4b;" \ + ".previous;" \ + : "=&r"(__gu_err) \ + : "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \ + ); \ +}) + +/** + * put_user: - Write a simple value into user space. + * @x: Value to copy to user space. + * @ptr: Destination address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple value from kernel space to user + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and @x must be assignable + * to the result of dereferencing @ptr. + * + * Returns zero on success, or -EFAULT on error. + */ + #define __put_user(x, ptr) \ ({ \ __typeof__(*(ptr)) volatile __gu_val = (x); \ @@ -195,7 +275,7 @@ extern long strnlen_user(const char *src, long count); case 1: \ __put_user_asm("sb", (ptr), __gu_val, __gu_err); \ break; \ - case 2: \ + case 2: \ __put_user_asm("sh", (ptr), __gu_val, __gu_err); \ break; \ case 4: \ @@ -205,121 +285,82 @@ extern long strnlen_user(const char *src, long count); __put_user_asm_8((ptr), __gu_val, __gu_err); \ break; \ default: \ - __gu_err = -EINVAL; \ + /*__gu_err = -EINVAL;*/ __gu_err = __user_bad(); \ } \ __gu_err; \ }) -#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \ -({ \ -__asm__ __volatile__ (" lwi %0, %1, 0; \ - 1: swi %0, %2, 0; \ - lwi %0, %1, 4; \ - 2: swi %0, %2, 4; \ - addk %0,r0,r0; \ - 3: \ - .section .fixup,\"ax\"; \ - 4: brid 3b; \ - addik %0, r0, %3; \ - .previous; \ - .section __ex_table,\"a\"; \ - .word 1b,4b,2b,4b; \ - .previous;" \ - : "=&r"(__gu_err) \ - : "r"(&__gu_val), \ - "r"(__gu_ptr), "i"(-EFAULT) \ - ); \ -}) +#ifndef CONFIG_MMU -#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ -({ \ - __asm__ __volatile__ ( \ - "1:" insn " %1, %2, r0; \ - addk %0, r0, r0; \ - 2: \ - .section .fixup,\"ax\"; \ - 3: brid 2b; \ - addik %0, r0, %3; \ - .previous; \ - .section __ex_table,\"a\"; \ - .word 1b,3b; \ - .previous;" \ - : "=r"(__gu_err) \ - : "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \ - ); \ -}) +#define put_user(x, ptr) __put_user((x), (ptr)) -/* - * Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. - */ -static inline int clear_user(char *to, int size) -{ - if (size && access_ok(VERIFY_WRITE, to, size)) { - __asm__ __volatile__ (" \ - 1: \ - sb r0, %2, r0; \ - addik %0, %0, -1; \ - bneid %0, 1b; \ - addik %2, %2, 1; \ - 2: \ - .section __ex_table,\"a\"; \ - .word 1b,2b; \ - .section .text;" \ - : "=r"(size) \ - : "0"(size), "r"(to) - ); - } - return size; -} +#else /* CONFIG_MMU */ -#define __copy_from_user(to, from, n) copy_from_user((to), (from), (n)) +#define put_user(x, ptr) \ +({ \ + access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) \ + ? __put_user((x), (ptr)) : -EFAULT; \ +}) +#endif /* CONFIG_MMU */ + +/* copy_to_from_user */ +#define __copy_from_user(to, from, n) \ + __copy_tofrom_user((__force void __user *)(to), \ + (void __user *)(from), (n)) #define __copy_from_user_inatomic(to, from, n) \ copy_from_user((to), (from), (n)) -#define copy_to_user(to, from, n) \ - (access_ok(VERIFY_WRITE, (to), (n)) ? \ - __copy_tofrom_user((void __user *)(to), \ - (__force const void __user *)(from), (n)) \ - : -EFAULT) +static inline long copy_from_user(void *to, + const void __user *from, unsigned long n) +{ + might_sleep(); + if (access_ok(VERIFY_READ, from, n)) + return __copy_from_user(to, from, n); + return n; +} -#define __copy_to_user(to, from, n) copy_to_user((to), (from), (n)) +#define __copy_to_user(to, from, n) \ + __copy_tofrom_user((void __user *)(to), \ + (__force const void __user *)(from), (n)) #define __copy_to_user_inatomic(to, from, n) copy_to_user((to), (from), (n)) -#define copy_from_user(to, from, n) \ - (access_ok(VERIFY_READ, (from), (n)) ? \ - __copy_tofrom_user((__force void __user *)(to), \ - (void __user *)(from), (n)) \ - : -EFAULT) +static inline long copy_to_user(void __user *to, + const void *from, unsigned long n) +{ + might_sleep(); + if (access_ok(VERIFY_WRITE, to, n)) + return __copy_to_user(to, from, n); + return n; +} +/* + * Copy a null terminated string from userspace. + */ extern int __strncpy_user(char *to, const char __user *from, int len); -extern int __strnlen_user(const char __user *sstr, int len); -#define strncpy_from_user(to, from, len) \ - (access_ok(VERIFY_READ, from, 1) ? \ - __strncpy_user(to, from, len) : -EFAULT) -#define strnlen_user(str, len) \ - (access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0) +#define __strncpy_from_user __strncpy_user -#endif /* CONFIG_MMU */ - -extern unsigned long __copy_tofrom_user(void __user *to, - const void __user *from, unsigned long size); +static inline long +strncpy_from_user(char *dst, const char __user *src, long count) +{ + if (!access_ok(VERIFY_READ, src, 1)) + return -EFAULT; + return __strncpy_from_user(dst, src, count); +} /* - * 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. + * Return the size of a string (including the ending 0) * - * 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. + * Return 0 on exception, a value greater than N if too long */ -struct exception_table_entry { - unsigned long insn, fixup; -}; +extern int __strnlen_user(const char __user *sstr, int len); + +static inline long strnlen_user(const char __user *src, long n) +{ + if (!access_ok(VERIFY_READ, src, 1)) + return 0; + return __strnlen_user(src, n); +} #endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ |