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#ifndef __PARISC_UACCESS_H
#define __PARISC_UACCESS_H
/*
* User space memory access functions
*/
#include <asm/page.h>
#include <asm/cache.h>
#include <asm-generic/uaccess-unaligned.h>
#include <linux/bug.h>
#include <linux/string.h>
#define KERNEL_DS ((mm_segment_t){0})
#define USER_DS ((mm_segment_t){1})
#define segment_eq(a, b) ((a).seg == (b).seg)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
/*
* Note that since kernel addresses are in a separate address space on
* parisc, we don't need to do anything for access_ok().
* We just let the page fault handler do the right thing. This also means
* that put_user is the same as __put_user, etc.
*/
#define access_ok(type, uaddr, size) \
( (uaddr) == (uaddr) )
#define put_user __put_user
#define get_user __get_user
#if !defined(CONFIG_64BIT)
#define LDD_USER(ptr) __get_user_asm64(ptr)
#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
#else
#define LDD_USER(ptr) __get_user_asm("ldd", ptr)
#define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
#endif
/*
* The exception table contains two values: the first is the relative offset to
* the address of the instruction that is allowed to fault, and the second is
* the relative offset to the address of the fixup routine. Since relative
* addresses are used, 32bit values are sufficient even on 64bit kernel.
*/
#define ARCH_HAS_RELATIVE_EXTABLE
struct exception_table_entry {
int insn; /* relative address of insn that is allowed to fault. */
int fixup; /* relative address of fixup routine */
};
#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
".section __ex_table,\"aw\"\n" \
".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
".previous\n"
/*
* ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry
* (with lowest bit set) for which the fault handler in fixup_exception() will
* load -EFAULT into %r8 for a read or write fault, and zeroes the target
* register in case of a read fault in get_user().
*/
#define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\
ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1)
/*
* The page fault handler stores, in a per-cpu area, the following information
* if a fixup routine is available.
*/
struct exception_data {
unsigned long fault_ip;
unsigned long fault_gp;
unsigned long fault_space;
unsigned long fault_addr;
};
/*
* load_sr2() preloads the space register %%sr2 - based on the value of
* get_fs() - with either a value of 0 to access kernel space (KERNEL_DS which
* is 0), or with the current value of %%sr3 to access user space (USER_DS)
* memory. The following __get_user_asm() and __put_user_asm() functions have
* %%sr2 hard-coded to access the requested memory.
*/
#define load_sr2() \
__asm__(" or,= %0,%%r0,%%r0\n\t" \
" mfsp %%sr3,%0\n\t" \
" mtsp %0,%%sr2\n\t" \
: : "r"(get_fs()) : )
#define __get_user(x, ptr) \
({ \
register long __gu_err __asm__ ("r8") = 0; \
register long __gu_val; \
\
load_sr2(); \
switch (sizeof(*(ptr))) { \
case 1: __get_user_asm("ldb", ptr); break; \
case 2: __get_user_asm("ldh", ptr); break; \
case 4: __get_user_asm("ldw", ptr); break; \
case 8: LDD_USER(ptr); break; \
default: BUILD_BUG(); break; \
} \
\
(x) = (__force __typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_user_asm(ldx, ptr) \
__asm__("1: " ldx " 0(%%sr2,%2),%0\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err));
#if !defined(CONFIG_64BIT)
#define __get_user_asm64(ptr) \
__asm__(" copy %%r0,%R0\n" \
"1: ldw 0(%%sr2,%2),%0\n" \
"2: ldw 4(%%sr2,%2),%R0\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err));
#endif /* !defined(CONFIG_64BIT) */
#define __put_user(x, ptr) \
({ \
register long __pu_err __asm__ ("r8") = 0; \
__typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
\
load_sr2(); \
switch (sizeof(*(ptr))) { \
case 1: __put_user_asm("stb", __x, ptr); break; \
case 2: __put_user_asm("sth", __x, ptr); break; \
case 4: __put_user_asm("stw", __x, ptr); break; \
case 8: STD_USER(__x, ptr); break; \
default: BUILD_BUG(); break; \
} \
\
__pu_err; \
})
/*
* The "__put_user/kernel_asm()" macros tell gcc they read from memory
* instead of writing. This is because they do not write to any memory
* gcc knows about, so there are no aliasing issues. These macros must
* also be aware that fixups are executed in the context of the fault,
* and any registers used there must be listed as clobbers.
* r8 is already listed as err.
*/
#define __put_user_asm(stx, x, ptr) \
__asm__ __volatile__ ( \
"1: " stx " %2,0(%%sr2,%1)\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err))
#if !defined(CONFIG_64BIT)
#define __put_user_asm64(__val, ptr) do { \
__asm__ __volatile__ ( \
"1: stw %2,0(%%sr2,%1)\n" \
"2: stw %R2,4(%%sr2,%1)\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
: "=r"(__pu_err) \
: "r"(ptr), "r"(__val), "0"(__pu_err)); \
} while (0)
#endif /* !defined(CONFIG_64BIT) */
/*
* Complex access routines -- external declarations
*/
extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
extern long strncpy_from_user(char *, const char __user *, long);
extern unsigned lclear_user(void __user *, unsigned long);
extern long lstrnlen_user(const char __user *, long);
/*
* Complex access routines -- macros
*/
#define user_addr_max() (~0UL)
#define strnlen_user lstrnlen_user
#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
#define clear_user lclear_user
#define __clear_user lclear_user
unsigned long __must_check __copy_to_user(void __user *dst, const void *src,
unsigned long len);
unsigned long __must_check __copy_from_user(void *dst, const void __user *src,
unsigned long len);
unsigned long copy_in_user(void __user *dst, const void __user *src,
unsigned long len);
#define __copy_in_user copy_in_user
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
extern void __compiletime_error("usercopy buffer size is too small")
__bad_copy_user(void);
static inline void copy_user_overflow(int size, unsigned long count)
{
WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
}
static __always_inline unsigned long __must_check
copy_from_user(void *to, const void __user *from, unsigned long n)
{
int sz = __compiletime_object_size(to);
unsigned long ret = n;
if (likely(sz < 0 || sz >= n)) {
check_object_size(to, n, false);
ret = __copy_from_user(to, from, n);
} else if (!__builtin_constant_p(n))
copy_user_overflow(sz, n);
else
__bad_copy_user();
if (unlikely(ret))
memset(to + (n - ret), 0, ret);
return ret;
}
static __always_inline unsigned long __must_check
copy_to_user(void __user *to, const void *from, unsigned long n)
{
int sz = __compiletime_object_size(from);
if (likely(sz < 0 || sz >= n)) {
check_object_size(from, n, true);
n = __copy_to_user(to, from, n);
} else if (!__builtin_constant_p(n))
copy_user_overflow(sz, n);
else
__bad_copy_user();
return n;
}
struct pt_regs;
int fixup_exception(struct pt_regs *regs);
#endif /* __PARISC_UACCESS_H */
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