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- #ifndef __ALPHA_UACCESS_H
- #define __ALPHA_UACCESS_H
- #include <linux/errno.h>
- #include <linux/sched.h>
- /*
- * 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.
- *
- * Or at least it did once upon a time. Nowadays it is a mask that
- * defines which bits of the address space are off limits. This is a
- * wee bit faster than the above.
- *
- * For historical reasons, these macros are grossly misnamed.
- */
- #define KERNEL_DS ((mm_segment_t) { 0UL })
- #define USER_DS ((mm_segment_t) { -0x40000000000UL })
- #define VERIFY_READ 0
- #define VERIFY_WRITE 1
- #define get_fs() (current_thread_info()->addr_limit)
- #define get_ds() (KERNEL_DS)
- #define set_fs(x) (current_thread_info()->addr_limit = (x))
- #define segment_eq(a, b) ((a).seg == (b).seg)
- /*
- * Is a address valid? This does a straightforward calculation rather
- * than tests.
- *
- * Address valid if:
- * - "addr" doesn't have any high-bits set
- * - AND "size" doesn't have any high-bits set
- * - AND "addr+size" doesn't have any high-bits set
- * - OR we are in kernel mode.
- */
- #define __access_ok(addr, size, segment) \
- (((segment).seg & (addr | size | (addr+size))) == 0)
- #define access_ok(type, addr, size) \
- ({ \
- __chk_user_ptr(addr); \
- __access_ok(((unsigned long)(addr)), (size), get_fs()); \
- })
- /*
- * These are the main single-value transfer routines. They automatically
- * use the right size if we just have the right pointer type.
- *
- * As the alpha uses the same address space for kernel and user
- * data, we can just do these as direct assignments. (Of course, the
- * exception handling means that it's no longer "just"...)
- *
- * Careful to not
- * (a) re-use the arguments for side effects (sizeof/typeof is ok)
- * (b) require any knowledge of processes at this stage
- */
- #define put_user(x, ptr) \
- __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), get_fs())
- #define get_user(x, ptr) \
- __get_user_check((x), (ptr), sizeof(*(ptr)), get_fs())
- /*
- * The "__xxx" versions do not do address space checking, useful when
- * doing multiple accesses to the same area (the programmer 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)))
-
- /*
- * The "lda %1, 2b-1b(%0)" bits are magic to get the assembler to
- * encode the bits we need for resolving the exception. See the
- * more extensive comments with fixup_inline_exception below for
- * more information.
- */
- extern void __get_user_unknown(void);
- #define __get_user_nocheck(x, ptr, size) \
- ({ \
- long __gu_err = 0; \
- unsigned long __gu_val; \
- __chk_user_ptr(ptr); \
- switch (size) { \
- case 1: __get_user_8(ptr); break; \
- case 2: __get_user_16(ptr); break; \
- case 4: __get_user_32(ptr); break; \
- case 8: __get_user_64(ptr); break; \
- default: __get_user_unknown(); break; \
- } \
- (x) = (__force __typeof__(*(ptr))) __gu_val; \
- __gu_err; \
- })
- #define __get_user_check(x, ptr, size, segment) \
- ({ \
- long __gu_err = -EFAULT; \
- unsigned long __gu_val = 0; \
- const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
- if (__access_ok((unsigned long)__gu_addr, size, segment)) { \
- __gu_err = 0; \
- switch (size) { \
- case 1: __get_user_8(__gu_addr); break; \
- case 2: __get_user_16(__gu_addr); break; \
- case 4: __get_user_32(__gu_addr); break; \
- case 8: __get_user_64(__gu_addr); break; \
- default: __get_user_unknown(); break; \
- } \
- } \
- (x) = (__force __typeof__(*(ptr))) __gu_val; \
- __gu_err; \
- })
- struct __large_struct { unsigned long buf[100]; };
- #define __m(x) (*(struct __large_struct __user *)(x))
- #define __get_user_64(addr) \
- __asm__("1: ldq %0,%2\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda %0, 2b-1b(%1)\n" \
- ".previous" \
- : "=r"(__gu_val), "=r"(__gu_err) \
- : "m"(__m(addr)), "1"(__gu_err))
- #define __get_user_32(addr) \
- __asm__("1: ldl %0,%2\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda %0, 2b-1b(%1)\n" \
- ".previous" \
- : "=r"(__gu_val), "=r"(__gu_err) \
- : "m"(__m(addr)), "1"(__gu_err))
- #ifdef __alpha_bwx__
- /* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */
- #define __get_user_16(addr) \
- __asm__("1: ldwu %0,%2\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda %0, 2b-1b(%1)\n" \
- ".previous" \
- : "=r"(__gu_val), "=r"(__gu_err) \
- : "m"(__m(addr)), "1"(__gu_err))
- #define __get_user_8(addr) \
- __asm__("1: ldbu %0,%2\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda %0, 2b-1b(%1)\n" \
- ".previous" \
- : "=r"(__gu_val), "=r"(__gu_err) \
- : "m"(__m(addr)), "1"(__gu_err))
- #else
- /* Unfortunately, we can't get an unaligned access trap for the sub-word
- load, so we have to do a general unaligned operation. */
- #define __get_user_16(addr) \
- { \
- long __gu_tmp; \
- __asm__("1: ldq_u %0,0(%3)\n" \
- "2: ldq_u %1,1(%3)\n" \
- " extwl %0,%3,%0\n" \
- " extwh %1,%3,%1\n" \
- " or %0,%1,%0\n" \
- "3:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda %0, 3b-1b(%2)\n" \
- " .long 2b - .\n" \
- " lda %0, 3b-2b(%2)\n" \
- ".previous" \
- : "=&r"(__gu_val), "=&r"(__gu_tmp), "=r"(__gu_err) \
- : "r"(addr), "2"(__gu_err)); \
- }
- #define __get_user_8(addr) \
- __asm__("1: ldq_u %0,0(%2)\n" \
- " extbl %0,%2,%0\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda %0, 2b-1b(%1)\n" \
- ".previous" \
- : "=&r"(__gu_val), "=r"(__gu_err) \
- : "r"(addr), "1"(__gu_err))
- #endif
- extern void __put_user_unknown(void);
- #define __put_user_nocheck(x, ptr, size) \
- ({ \
- long __pu_err = 0; \
- __chk_user_ptr(ptr); \
- switch (size) { \
- case 1: __put_user_8(x, ptr); break; \
- case 2: __put_user_16(x, ptr); break; \
- case 4: __put_user_32(x, ptr); break; \
- case 8: __put_user_64(x, ptr); break; \
- default: __put_user_unknown(); break; \
- } \
- __pu_err; \
- })
- #define __put_user_check(x, ptr, size, segment) \
- ({ \
- long __pu_err = -EFAULT; \
- __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
- if (__access_ok((unsigned long)__pu_addr, size, segment)) { \
- __pu_err = 0; \
- switch (size) { \
- case 1: __put_user_8(x, __pu_addr); break; \
- case 2: __put_user_16(x, __pu_addr); break; \
- case 4: __put_user_32(x, __pu_addr); break; \
- case 8: __put_user_64(x, __pu_addr); break; \
- default: __put_user_unknown(); break; \
- } \
- } \
- __pu_err; \
- })
- /*
- * The "__put_user_xx()" 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
- */
- #define __put_user_64(x, addr) \
- __asm__ __volatile__("1: stq %r2,%1\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda $31,2b-1b(%0)\n" \
- ".previous" \
- : "=r"(__pu_err) \
- : "m" (__m(addr)), "rJ" (x), "0"(__pu_err))
- #define __put_user_32(x, addr) \
- __asm__ __volatile__("1: stl %r2,%1\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda $31,2b-1b(%0)\n" \
- ".previous" \
- : "=r"(__pu_err) \
- : "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
- #ifdef __alpha_bwx__
- /* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */
- #define __put_user_16(x, addr) \
- __asm__ __volatile__("1: stw %r2,%1\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda $31,2b-1b(%0)\n" \
- ".previous" \
- : "=r"(__pu_err) \
- : "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
- #define __put_user_8(x, addr) \
- __asm__ __volatile__("1: stb %r2,%1\n" \
- "2:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda $31,2b-1b(%0)\n" \
- ".previous" \
- : "=r"(__pu_err) \
- : "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
- #else
- /* Unfortunately, we can't get an unaligned access trap for the sub-word
- write, so we have to do a general unaligned operation. */
- #define __put_user_16(x, addr) \
- { \
- long __pu_tmp1, __pu_tmp2, __pu_tmp3, __pu_tmp4; \
- __asm__ __volatile__( \
- "1: ldq_u %2,1(%5)\n" \
- "2: ldq_u %1,0(%5)\n" \
- " inswh %6,%5,%4\n" \
- " inswl %6,%5,%3\n" \
- " mskwh %2,%5,%2\n" \
- " mskwl %1,%5,%1\n" \
- " or %2,%4,%2\n" \
- " or %1,%3,%1\n" \
- "3: stq_u %2,1(%5)\n" \
- "4: stq_u %1,0(%5)\n" \
- "5:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda $31, 5b-1b(%0)\n" \
- " .long 2b - .\n" \
- " lda $31, 5b-2b(%0)\n" \
- " .long 3b - .\n" \
- " lda $31, 5b-3b(%0)\n" \
- " .long 4b - .\n" \
- " lda $31, 5b-4b(%0)\n" \
- ".previous" \
- : "=r"(__pu_err), "=&r"(__pu_tmp1), \
- "=&r"(__pu_tmp2), "=&r"(__pu_tmp3), \
- "=&r"(__pu_tmp4) \
- : "r"(addr), "r"((unsigned long)(x)), "0"(__pu_err)); \
- }
- #define __put_user_8(x, addr) \
- { \
- long __pu_tmp1, __pu_tmp2; \
- __asm__ __volatile__( \
- "1: ldq_u %1,0(%4)\n" \
- " insbl %3,%4,%2\n" \
- " mskbl %1,%4,%1\n" \
- " or %1,%2,%1\n" \
- "2: stq_u %1,0(%4)\n" \
- "3:\n" \
- ".section __ex_table,\"a\"\n" \
- " .long 1b - .\n" \
- " lda $31, 3b-1b(%0)\n" \
- " .long 2b - .\n" \
- " lda $31, 3b-2b(%0)\n" \
- ".previous" \
- : "=r"(__pu_err), \
- "=&r"(__pu_tmp1), "=&r"(__pu_tmp2) \
- : "r"((unsigned long)(x)), "r"(addr), "0"(__pu_err)); \
- }
- #endif
- /*
- * Complex access routines
- */
- /* This little bit of silliness is to get the GP loaded for a function
- that ordinarily wouldn't. Otherwise we could have it done by the macro
- directly, which can be optimized the linker. */
- #ifdef MODULE
- #define __module_address(sym) "r"(sym),
- #define __module_call(ra, arg, sym) "jsr $" #ra ",(%" #arg ")," #sym
- #else
- #define __module_address(sym)
- #define __module_call(ra, arg, sym) "bsr $" #ra "," #sym " !samegp"
- #endif
- extern void __copy_user(void);
- extern inline long
- __copy_tofrom_user_nocheck(void *to, const void *from, long len)
- {
- register void * __cu_to __asm__("$6") = to;
- register const void * __cu_from __asm__("$7") = from;
- register long __cu_len __asm__("$0") = len;
- __asm__ __volatile__(
- __module_call(28, 3, __copy_user)
- : "=r" (__cu_len), "=r" (__cu_from), "=r" (__cu_to)
- : __module_address(__copy_user)
- "0" (__cu_len), "1" (__cu_from), "2" (__cu_to)
- : "$1", "$2", "$3", "$4", "$5", "$28", "memory");
- return __cu_len;
- }
- #define __copy_to_user(to, from, n) \
- ({ \
- __chk_user_ptr(to); \
- __copy_tofrom_user_nocheck((__force void *)(to), (from), (n)); \
- })
- #define __copy_from_user(to, from, n) \
- ({ \
- __chk_user_ptr(from); \
- __copy_tofrom_user_nocheck((to), (__force void *)(from), (n)); \
- })
- #define __copy_to_user_inatomic __copy_to_user
- #define __copy_from_user_inatomic __copy_from_user
- extern inline long
- copy_to_user(void __user *to, const void *from, long n)
- {
- if (likely(__access_ok((unsigned long)to, n, get_fs())))
- n = __copy_tofrom_user_nocheck((__force void *)to, from, n);
- return n;
- }
- extern inline long
- copy_from_user(void *to, const void __user *from, long n)
- {
- long res = n;
- if (likely(__access_ok((unsigned long)from, n, get_fs())))
- res = __copy_from_user_inatomic(to, from, n);
- if (unlikely(res))
- memset(to + (n - res), 0, res);
- return res;
- }
- extern void __do_clear_user(void);
- extern inline long
- __clear_user(void __user *to, long len)
- {
- register void __user * __cl_to __asm__("$6") = to;
- register long __cl_len __asm__("$0") = len;
- __asm__ __volatile__(
- __module_call(28, 2, __do_clear_user)
- : "=r"(__cl_len), "=r"(__cl_to)
- : __module_address(__do_clear_user)
- "0"(__cl_len), "1"(__cl_to)
- : "$1", "$2", "$3", "$4", "$5", "$28", "memory");
- return __cl_len;
- }
- extern inline long
- clear_user(void __user *to, long len)
- {
- if (__access_ok((unsigned long)to, len, get_fs()))
- len = __clear_user(to, len);
- return len;
- }
- #undef __module_address
- #undef __module_call
- #define user_addr_max() \
- (segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL)
- extern long strncpy_from_user(char *dest, const char __user *src, long count);
- extern __must_check long strlen_user(const char __user *str);
- extern __must_check long strnlen_user(const char __user *str, long n);
- /*
- * About the exception table:
- *
- * - insn is a 32-bit pc-relative offset from the faulting insn.
- * - nextinsn is a 16-bit offset off of the faulting instruction
- * (not off of the *next* instruction as branches are).
- * - errreg is the register in which to place -EFAULT.
- * - valreg is the final target register for the load sequence
- * and will be zeroed.
- *
- * Either errreg or valreg may be $31, in which case nothing happens.
- *
- * The exception fixup information "just so happens" to be arranged
- * as in a MEM format instruction. This lets us emit our three
- * values like so:
- *
- * lda valreg, nextinsn(errreg)
- *
- */
- struct exception_table_entry
- {
- signed int insn;
- union exception_fixup {
- unsigned unit;
- struct {
- signed int nextinsn : 16;
- unsigned int errreg : 5;
- unsigned int valreg : 5;
- } bits;
- } fixup;
- };
- /* Returns the new pc */
- #define fixup_exception(map_reg, _fixup, pc) \
- ({ \
- if ((_fixup)->fixup.bits.valreg != 31) \
- map_reg((_fixup)->fixup.bits.valreg) = 0; \
- if ((_fixup)->fixup.bits.errreg != 31) \
- map_reg((_fixup)->fixup.bits.errreg) = -EFAULT; \
- (pc) + (_fixup)->fixup.bits.nextinsn; \
- })
- #define ARCH_HAS_RELATIVE_EXTABLE
- #define swap_ex_entry_fixup(a, b, tmp, delta) \
- do { \
- (a)->fixup.unit = (b)->fixup.unit; \
- (b)->fixup.unit = (tmp).fixup.unit; \
- } while (0)
- #endif /* __ALPHA_UACCESS_H */
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