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Diffstat (limited to 'arch/s390/include/asm/uaccess.h')
| -rw-r--r-- | arch/s390/include/asm/uaccess.h | 377 |
1 files changed, 377 insertions, 0 deletions
diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h new file mode 100644 index 000000000..d64a7a621 --- /dev/null +++ b/arch/s390/include/asm/uaccess.h @@ -0,0 +1,377 @@ +/* + * S390 version + * Copyright IBM Corp. 1999, 2000 + * Author(s): Hartmut Penner (hp@de.ibm.com), + * Martin Schwidefsky (schwidefsky@de.ibm.com) + * + * Derived from "include/asm-i386/uaccess.h" + */ +#ifndef __S390_UACCESS_H +#define __S390_UACCESS_H + +/* + * User space memory access functions + */ +#include <linux/sched.h> +#include <linux/errno.h> +#include <asm/ctl_reg.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(a) ((mm_segment_t) { (a) }) + + +#define KERNEL_DS MAKE_MM_SEG(0) +#define USER_DS MAKE_MM_SEG(1) + +#define get_ds() (KERNEL_DS) +#define get_fs() (current->thread.mm_segment) + +#define set_fs(x) \ +({ \ + unsigned long __pto; \ + current->thread.mm_segment = (x); \ + __pto = current->thread.mm_segment.ar4 ? \ + S390_lowcore.user_asce : S390_lowcore.kernel_asce; \ + __ctl_load(__pto, 7, 7); \ +}) + +#define segment_eq(a,b) ((a).ar4 == (b).ar4) + +static inline int __range_ok(unsigned long addr, unsigned long size) +{ + return 1; +} + +#define __access_ok(addr, size) \ +({ \ + __chk_user_ptr(addr); \ + __range_ok((unsigned long)(addr), (size)); \ +}) + +#define access_ok(type, addr, size) __access_ok(addr, size) + +/* + * 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 +{ + int insn, fixup; +}; + +static inline unsigned long extable_insn(const struct exception_table_entry *x) +{ + return (unsigned long)&x->insn + x->insn; +} + +static inline unsigned long extable_fixup(const struct exception_table_entry *x) +{ + return (unsigned long)&x->fixup + x->fixup; +} + +#define ARCH_HAS_SORT_EXTABLE +#define ARCH_HAS_SEARCH_EXTABLE + +/** + * __copy_from_user: - Copy a block of data from user space, with less checking. + * @to: Destination address, in kernel space. + * @from: Source address, in user space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from user space to kernel space. Caller must check + * the specified block with access_ok() before calling this function. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + * + * If some data could not be copied, this function will pad the copied + * data to the requested size using zero bytes. + */ +unsigned long __must_check __copy_from_user(void *to, const void __user *from, + unsigned long n); + +/** + * __copy_to_user: - Copy a block of data into user space, with less checking. + * @to: Destination address, in user space. + * @from: Source address, in kernel space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from kernel space to user space. Caller must check + * the specified block with access_ok() before calling this function. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + */ +unsigned long __must_check __copy_to_user(void __user *to, const void *from, + unsigned long n); + +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user + +#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES + +#define __put_get_user_asm(to, from, size, spec) \ +({ \ + register unsigned long __reg0 asm("0") = spec; \ + int __rc; \ + \ + asm volatile( \ + "0: mvcos %1,%3,%2\n" \ + "1: xr %0,%0\n" \ + "2:\n" \ + ".pushsection .fixup, \"ax\"\n" \ + "3: lhi %0,%5\n" \ + " jg 2b\n" \ + ".popsection\n" \ + EX_TABLE(0b,3b) EX_TABLE(1b,3b) \ + : "=d" (__rc), "=Q" (*(to)) \ + : "d" (size), "Q" (*(from)), \ + "d" (__reg0), "K" (-EFAULT) \ + : "cc"); \ + __rc; \ +}) + +#define __put_user_fn(x, ptr, size) __put_get_user_asm(ptr, x, size, 0x810000UL) +#define __get_user_fn(x, ptr, size) __put_get_user_asm(x, ptr, size, 0x81UL) + +#else /* CONFIG_HAVE_MARCH_Z10_FEATURES */ + +static inline int __put_user_fn(void *x, void __user *ptr, unsigned long size) +{ + size = __copy_to_user(ptr, x, size); + return size ? -EFAULT : 0; +} + +static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size) +{ + size = __copy_from_user(x, ptr, size); + return size ? -EFAULT : 0; +} + +#endif /* CONFIG_HAVE_MARCH_Z10_FEATURES */ + +/* + * 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) \ +({ \ + __typeof__(*(ptr)) __x = (x); \ + int __pu_err = -EFAULT; \ + __chk_user_ptr(ptr); \ + switch (sizeof (*(ptr))) { \ + case 1: \ + case 2: \ + case 4: \ + case 8: \ + __pu_err = __put_user_fn(&__x, ptr, \ + sizeof(*(ptr))); \ + break; \ + default: \ + __put_user_bad(); \ + break; \ + } \ + __pu_err; \ +}) + +#define put_user(x, ptr) \ +({ \ + might_fault(); \ + __put_user(x, ptr); \ +}) + + +int __put_user_bad(void) __attribute__((noreturn)); + +#define __get_user(x, ptr) \ +({ \ + int __gu_err = -EFAULT; \ + __chk_user_ptr(ptr); \ + switch (sizeof(*(ptr))) { \ + case 1: { \ + unsigned char __x; \ + __gu_err = __get_user_fn(&__x, ptr, \ + sizeof(*(ptr))); \ + (x) = *(__force __typeof__(*(ptr)) *) &__x; \ + break; \ + }; \ + case 2: { \ + unsigned short __x; \ + __gu_err = __get_user_fn(&__x, ptr, \ + sizeof(*(ptr))); \ + (x) = *(__force __typeof__(*(ptr)) *) &__x; \ + break; \ + }; \ + case 4: { \ + unsigned int __x; \ + __gu_err = __get_user_fn(&__x, ptr, \ + sizeof(*(ptr))); \ + (x) = *(__force __typeof__(*(ptr)) *) &__x; \ + break; \ + }; \ + case 8: { \ + unsigned long long __x; \ + __gu_err = __get_user_fn(&__x, ptr, \ + sizeof(*(ptr))); \ + (x) = *(__force __typeof__(*(ptr)) *) &__x; \ + break; \ + }; \ + default: \ + __get_user_bad(); \ + break; \ + } \ + __gu_err; \ +}) + +#define get_user(x, ptr) \ +({ \ + might_fault(); \ + __get_user(x, ptr); \ +}) + +int __get_user_bad(void) __attribute__((noreturn)); + +#define __put_user_unaligned __put_user +#define __get_user_unaligned __get_user + +/** + * copy_to_user: - Copy a block of data into user space. + * @to: Destination address, in user space. + * @from: Source address, in kernel space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from kernel space to user space. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + */ +static inline unsigned long __must_check +copy_to_user(void __user *to, const void *from, unsigned long n) +{ + might_fault(); + return __copy_to_user(to, from, n); +} + +void copy_from_user_overflow(void) +#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS +__compiletime_warning("copy_from_user() buffer size is not provably correct") +#endif +; + +/** + * copy_from_user: - Copy a block of data from user space. + * @to: Destination address, in kernel space. + * @from: Source address, in user space. + * @n: Number of bytes to copy. + * + * Context: User context only. This function may sleep. + * + * Copy data from user space to kernel space. + * + * Returns number of bytes that could not be copied. + * On success, this will be zero. + * + * If some data could not be copied, this function will pad the copied + * data to the requested size using zero bytes. + */ +static inline unsigned long __must_check +copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned int sz = __compiletime_object_size(to); + + might_fault(); + if (unlikely(sz != -1 && sz < n)) { + copy_from_user_overflow(); + return n; + } + return __copy_from_user(to, from, n); +} + +unsigned long __must_check +__copy_in_user(void __user *to, const void __user *from, unsigned long n); + +static inline unsigned long __must_check +copy_in_user(void __user *to, const void __user *from, unsigned long n) +{ + might_fault(); + return __copy_in_user(to, from, n); +} + +/* + * Copy a null terminated string from userspace. + */ + +long __strncpy_from_user(char *dst, const char __user *src, long count); + +static inline long __must_check +strncpy_from_user(char *dst, const char __user *src, long count) +{ + might_fault(); + return __strncpy_from_user(dst, src, count); +} + +unsigned long __must_check __strnlen_user(const char __user *src, unsigned long count); + +static inline unsigned long strnlen_user(const char __user *src, unsigned long n) +{ + might_fault(); + return __strnlen_user(src, n); +} + +/** + * strlen_user: - Get the size of a string in user space. + * @str: The string to measure. + * + * Context: User context only. This function may sleep. + * + * Get the size of a NUL-terminated string in user space. + * + * Returns the size of the string INCLUDING the terminating NUL. + * On exception, returns 0. + * + * If there is a limit on the length of a valid string, you may wish to + * consider using strnlen_user() instead. + */ +#define strlen_user(str) strnlen_user(str, ~0UL) + +/* + * Zero Userspace + */ +unsigned long __must_check __clear_user(void __user *to, unsigned long size); + +static inline unsigned long __must_check clear_user(void __user *to, unsigned long n) +{ + might_fault(); + return __clear_user(to, n); +} + +int copy_to_user_real(void __user *dest, void *src, unsigned long count); +void s390_kernel_write(void *dst, const void *src, size_t size); + +#endif /* __S390_UACCESS_H */ |