diff options
Diffstat (limited to 'include/asm-cris/arch-v10/uaccess.h')
| -rw-r--r-- | include/asm-cris/arch-v10/uaccess.h | 660 |
1 files changed, 660 insertions, 0 deletions
diff --git a/include/asm-cris/arch-v10/uaccess.h b/include/asm-cris/arch-v10/uaccess.h new file mode 100644 index 00000000000..787d2e60c83 --- /dev/null +++ b/include/asm-cris/arch-v10/uaccess.h @@ -0,0 +1,660 @@ +/* + * Authors: Bjorn Wesen (bjornw@axis.com) + * Hans-Peter Nilsson (hp@axis.com) + * + */ +#ifndef _CRIS_ARCH_UACCESS_H +#define _CRIS_ARCH_UACCESS_H + +/* + * We don't tell gcc that we are accessing memory, but this is OK + * because we do not write to any memory gcc knows about, so there + * are no aliasing issues. + * + * Note that PC at a fault is the address *after* the faulting + * instruction. + */ +#define __put_user_asm(x, addr, err, op) \ + __asm__ __volatile__( \ + " "op" %1,[%2]\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + "3: move.d %3,%0\n" \ + " jump 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .dword 2b,3b\n" \ + " .previous\n" \ + : "=r" (err) \ + : "r" (x), "r" (addr), "g" (-EFAULT), "0" (err)) + +#define __put_user_asm_64(x, addr, err) \ + __asm__ __volatile__( \ + " move.d %M1,[%2]\n" \ + "2: move.d %H1,[%2+4]\n" \ + "4:\n" \ + " .section .fixup,\"ax\"\n" \ + "3: move.d %3,%0\n" \ + " jump 4b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .dword 2b,3b\n" \ + " .dword 4b,3b\n" \ + " .previous\n" \ + : "=r" (err) \ + : "r" (x), "r" (addr), "g" (-EFAULT), "0" (err)) + +/* See comment before __put_user_asm. */ + +#define __get_user_asm(x, addr, err, op) \ + __asm__ __volatile__( \ + " "op" [%2],%1\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + "3: move.d %3,%0\n" \ + " moveq 0,%1\n" \ + " jump 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .dword 2b,3b\n" \ + " .previous\n" \ + : "=r" (err), "=r" (x) \ + : "r" (addr), "g" (-EFAULT), "0" (err)) + +#define __get_user_asm_64(x, addr, err) \ + __asm__ __volatile__( \ + " move.d [%2],%M1\n" \ + "2: move.d [%2+4],%H1\n" \ + "4:\n" \ + " .section .fixup,\"ax\"\n" \ + "3: move.d %3,%0\n" \ + " moveq 0,%1\n" \ + " jump 4b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .dword 2b,3b\n" \ + " .dword 4b,3b\n" \ + " .previous\n" \ + : "=r" (err), "=r" (x) \ + : "r" (addr), "g" (-EFAULT), "0" (err)) + +/* + * Copy a null terminated string from userspace. + * + * Must return: + * -EFAULT for an exception + * count if we hit the buffer limit + * bytes copied if we hit a null byte + * (without the null byte) + */ +extern inline long +__do_strncpy_from_user(char *dst, const char *src, long count) +{ + long res; + + if (count == 0) + return 0; + + /* + * Currently, in 2.4.0-test9, most ports use a simple byte-copy loop. + * So do we. + * + * This code is deduced from: + * + * char tmp2; + * long tmp1, tmp3 + * tmp1 = count; + * while ((*dst++ = (tmp2 = *src++)) != 0 + * && --tmp1) + * ; + * + * res = count - tmp1; + * + * with tweaks. + */ + + __asm__ __volatile__ ( + " move.d %3,%0\n" + " move.b [%2+],$r9\n" + "1: beq 2f\n" + " move.b $r9,[%1+]\n" + + " subq 1,%0\n" + " bne 1b\n" + " move.b [%2+],$r9\n" + + "2: sub.d %3,%0\n" + " neg.d %0,%0\n" + "3:\n" + " .section .fixup,\"ax\"\n" + "4: move.d %7,%0\n" + " jump 3b\n" + + /* There's one address for a fault at the first move, and + two possible PC values for a fault at the second move, + being a delay-slot filler. However, the branch-target + for the second move is the same as the first address. + Just so you don't get confused... */ + " .previous\n" + " .section __ex_table,\"a\"\n" + " .dword 1b,4b\n" + " .dword 2b,4b\n" + " .previous" + : "=r" (res), "=r" (dst), "=r" (src), "=r" (count) + : "3" (count), "1" (dst), "2" (src), "g" (-EFAULT) + : "r9"); + + return res; +} + +/* A few copy asms to build up the more complex ones from. + + Note again, a post-increment is performed regardless of whether a bus + fault occurred in that instruction, and PC for a faulted insn is the + address *after* the insn. */ + +#define __asm_copy_user_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm__ __volatile__ ( \ + COPY \ + "1:\n" \ + " .section .fixup,\"ax\"\n" \ + FIXUP \ + " jump 1b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + TENTRY \ + " .previous\n" \ + : "=r" (to), "=r" (from), "=r" (ret) \ + : "0" (to), "1" (from), "2" (ret) \ + : "r9", "memory") + +#define __asm_copy_from_user_1(to, from, ret) \ + __asm_copy_user_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "2: move.b $r9,[%0+]\n", \ + "3: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 2b,3b\n") + +#define __asm_copy_from_user_2x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_user_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + "2: move.w $r9,[%0+]\n" COPY, \ + "3: addq 2,%2\n" \ + " clear.w [%0+]\n" FIXUP, \ + " .dword 2b,3b\n" TENTRY) + +#define __asm_copy_from_user_2(to, from, ret) \ + __asm_copy_from_user_2x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_3(to, from, ret) \ + __asm_copy_from_user_2x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "4: move.b $r9,[%0+]\n", \ + "5: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 4b,5b\n") + +#define __asm_copy_from_user_4x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_user_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + "2: move.d $r9,[%0+]\n" COPY, \ + "3: addq 4,%2\n" \ + " clear.d [%0+]\n" FIXUP, \ + " .dword 2b,3b\n" TENTRY) + +#define __asm_copy_from_user_4(to, from, ret) \ + __asm_copy_from_user_4x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_5(to, from, ret) \ + __asm_copy_from_user_4x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "4: move.b $r9,[%0+]\n", \ + "5: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 4b,5b\n") + +#define __asm_copy_from_user_6x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_4x_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + "4: move.w $r9,[%0+]\n" COPY, \ + "5: addq 2,%2\n" \ + " clear.w [%0+]\n" FIXUP, \ + " .dword 4b,5b\n" TENTRY) + +#define __asm_copy_from_user_6(to, from, ret) \ + __asm_copy_from_user_6x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_7(to, from, ret) \ + __asm_copy_from_user_6x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "6: move.b $r9,[%0+]\n", \ + "7: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 6b,7b\n") + +#define __asm_copy_from_user_8x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_4x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + "4: move.d $r9,[%0+]\n" COPY, \ + "5: addq 4,%2\n" \ + " clear.d [%0+]\n" FIXUP, \ + " .dword 4b,5b\n" TENTRY) + +#define __asm_copy_from_user_8(to, from, ret) \ + __asm_copy_from_user_8x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_9(to, from, ret) \ + __asm_copy_from_user_8x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "6: move.b $r9,[%0+]\n", \ + "7: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 6b,7b\n") + +#define __asm_copy_from_user_10x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_8x_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + "6: move.w $r9,[%0+]\n" COPY, \ + "7: addq 2,%2\n" \ + " clear.w [%0+]\n" FIXUP, \ + " .dword 6b,7b\n" TENTRY) + +#define __asm_copy_from_user_10(to, from, ret) \ + __asm_copy_from_user_10x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_11(to, from, ret) \ + __asm_copy_from_user_10x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "8: move.b $r9,[%0+]\n", \ + "9: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 8b,9b\n") + +#define __asm_copy_from_user_12x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_8x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + "6: move.d $r9,[%0+]\n" COPY, \ + "7: addq 4,%2\n" \ + " clear.d [%0+]\n" FIXUP, \ + " .dword 6b,7b\n" TENTRY) + +#define __asm_copy_from_user_12(to, from, ret) \ + __asm_copy_from_user_12x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_13(to, from, ret) \ + __asm_copy_from_user_12x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "8: move.b $r9,[%0+]\n", \ + "9: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 8b,9b\n") + +#define __asm_copy_from_user_14x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_12x_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + "8: move.w $r9,[%0+]\n" COPY, \ + "9: addq 2,%2\n" \ + " clear.w [%0+]\n" FIXUP, \ + " .dword 8b,9b\n" TENTRY) + +#define __asm_copy_from_user_14(to, from, ret) \ + __asm_copy_from_user_14x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_15(to, from, ret) \ + __asm_copy_from_user_14x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + "10: move.b $r9,[%0+]\n", \ + "11: addq 1,%2\n" \ + " clear.b [%0+]\n", \ + " .dword 10b,11b\n") + +#define __asm_copy_from_user_16x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_12x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + "8: move.d $r9,[%0+]\n" COPY, \ + "9: addq 4,%2\n" \ + " clear.d [%0+]\n" FIXUP, \ + " .dword 8b,9b\n" TENTRY) + +#define __asm_copy_from_user_16(to, from, ret) \ + __asm_copy_from_user_16x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_20x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_16x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + "10: move.d $r9,[%0+]\n" COPY, \ + "11: addq 4,%2\n" \ + " clear.d [%0+]\n" FIXUP, \ + " .dword 10b,11b\n" TENTRY) + +#define __asm_copy_from_user_20(to, from, ret) \ + __asm_copy_from_user_20x_cont(to, from, ret, "", "", "") + +#define __asm_copy_from_user_24x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_from_user_20x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + "12: move.d $r9,[%0+]\n" COPY, \ + "13: addq 4,%2\n" \ + " clear.d [%0+]\n" FIXUP, \ + " .dword 12b,13b\n" TENTRY) + +#define __asm_copy_from_user_24(to, from, ret) \ + __asm_copy_from_user_24x_cont(to, from, ret, "", "", "") + +/* And now, the to-user ones. */ + +#define __asm_copy_to_user_1(to, from, ret) \ + __asm_copy_user_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n2:\n", \ + "3: addq 1,%2\n", \ + " .dword 2b,3b\n") + +#define __asm_copy_to_user_2x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_user_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + " move.w $r9,[%0+]\n2:\n" COPY, \ + "3: addq 2,%2\n" FIXUP, \ + " .dword 2b,3b\n" TENTRY) + +#define __asm_copy_to_user_2(to, from, ret) \ + __asm_copy_to_user_2x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_3(to, from, ret) \ + __asm_copy_to_user_2x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n4:\n", \ + "5: addq 1,%2\n", \ + " .dword 4b,5b\n") + +#define __asm_copy_to_user_4x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_user_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + " move.d $r9,[%0+]\n2:\n" COPY, \ + "3: addq 4,%2\n" FIXUP, \ + " .dword 2b,3b\n" TENTRY) + +#define __asm_copy_to_user_4(to, from, ret) \ + __asm_copy_to_user_4x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_5(to, from, ret) \ + __asm_copy_to_user_4x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n4:\n", \ + "5: addq 1,%2\n", \ + " .dword 4b,5b\n") + +#define __asm_copy_to_user_6x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_4x_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + " move.w $r9,[%0+]\n4:\n" COPY, \ + "5: addq 2,%2\n" FIXUP, \ + " .dword 4b,5b\n" TENTRY) + +#define __asm_copy_to_user_6(to, from, ret) \ + __asm_copy_to_user_6x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_7(to, from, ret) \ + __asm_copy_to_user_6x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n6:\n", \ + "7: addq 1,%2\n", \ + " .dword 6b,7b\n") + +#define __asm_copy_to_user_8x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_4x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + " move.d $r9,[%0+]\n4:\n" COPY, \ + "5: addq 4,%2\n" FIXUP, \ + " .dword 4b,5b\n" TENTRY) + +#define __asm_copy_to_user_8(to, from, ret) \ + __asm_copy_to_user_8x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_9(to, from, ret) \ + __asm_copy_to_user_8x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n6:\n", \ + "7: addq 1,%2\n", \ + " .dword 6b,7b\n") + +#define __asm_copy_to_user_10x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_8x_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + " move.w $r9,[%0+]\n6:\n" COPY, \ + "7: addq 2,%2\n" FIXUP, \ + " .dword 6b,7b\n" TENTRY) + +#define __asm_copy_to_user_10(to, from, ret) \ + __asm_copy_to_user_10x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_11(to, from, ret) \ + __asm_copy_to_user_10x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n8:\n", \ + "9: addq 1,%2\n", \ + " .dword 8b,9b\n") + +#define __asm_copy_to_user_12x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_8x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + " move.d $r9,[%0+]\n6:\n" COPY, \ + "7: addq 4,%2\n" FIXUP, \ + " .dword 6b,7b\n" TENTRY) + +#define __asm_copy_to_user_12(to, from, ret) \ + __asm_copy_to_user_12x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_13(to, from, ret) \ + __asm_copy_to_user_12x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n8:\n", \ + "9: addq 1,%2\n", \ + " .dword 8b,9b\n") + +#define __asm_copy_to_user_14x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_12x_cont(to, from, ret, \ + " move.w [%1+],$r9\n" \ + " move.w $r9,[%0+]\n8:\n" COPY, \ + "9: addq 2,%2\n" FIXUP, \ + " .dword 8b,9b\n" TENTRY) + +#define __asm_copy_to_user_14(to, from, ret) \ + __asm_copy_to_user_14x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_15(to, from, ret) \ + __asm_copy_to_user_14x_cont(to, from, ret, \ + " move.b [%1+],$r9\n" \ + " move.b $r9,[%0+]\n10:\n", \ + "11: addq 1,%2\n", \ + " .dword 10b,11b\n") + +#define __asm_copy_to_user_16x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_12x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + " move.d $r9,[%0+]\n8:\n" COPY, \ + "9: addq 4,%2\n" FIXUP, \ + " .dword 8b,9b\n" TENTRY) + +#define __asm_copy_to_user_16(to, from, ret) \ + __asm_copy_to_user_16x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_20x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_16x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + " move.d $r9,[%0+]\n10:\n" COPY, \ + "11: addq 4,%2\n" FIXUP, \ + " .dword 10b,11b\n" TENTRY) + +#define __asm_copy_to_user_20(to, from, ret) \ + __asm_copy_to_user_20x_cont(to, from, ret, "", "", "") + +#define __asm_copy_to_user_24x_cont(to, from, ret, COPY, FIXUP, TENTRY) \ + __asm_copy_to_user_20x_cont(to, from, ret, \ + " move.d [%1+],$r9\n" \ + " move.d $r9,[%0+]\n12:\n" COPY, \ + "13: addq 4,%2\n" FIXUP, \ + " .dword 12b,13b\n" TENTRY) + +#define __asm_copy_to_user_24(to, from, ret) \ + __asm_copy_to_user_24x_cont(to, from, ret, "", "", "") + +/* Define a few clearing asms with exception handlers. */ + +/* This frame-asm is like the __asm_copy_user_cont one, but has one less + input. */ + +#define __asm_clear(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm__ __volatile__ ( \ + CLEAR \ + "1:\n" \ + " .section .fixup,\"ax\"\n" \ + FIXUP \ + " jump 1b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + TENTRY \ + " .previous" \ + : "=r" (to), "=r" (ret) \ + : "0" (to), "1" (ret) \ + : "memory") + +#define __asm_clear_1(to, ret) \ + __asm_clear(to, ret, \ + " clear.b [%0+]\n2:\n", \ + "3: addq 1,%1\n", \ + " .dword 2b,3b\n") + +#define __asm_clear_2(to, ret) \ + __asm_clear(to, ret, \ + " clear.w [%0+]\n2:\n", \ + "3: addq 2,%1\n", \ + " .dword 2b,3b\n") + +#define __asm_clear_3(to, ret) \ + __asm_clear(to, ret, \ + " clear.w [%0+]\n" \ + "2: clear.b [%0+]\n3:\n", \ + "4: addq 2,%1\n" \ + "5: addq 1,%1\n", \ + " .dword 2b,4b\n" \ + " .dword 3b,5b\n") + +#define __asm_clear_4x_cont(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm_clear(to, ret, \ + " clear.d [%0+]\n2:\n" CLEAR, \ + "3: addq 4,%1\n" FIXUP, \ + " .dword 2b,3b\n" TENTRY) + +#define __asm_clear_4(to, ret) \ + __asm_clear_4x_cont(to, ret, "", "", "") + +#define __asm_clear_8x_cont(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm_clear_4x_cont(to, ret, \ + " clear.d [%0+]\n4:\n" CLEAR, \ + "5: addq 4,%1\n" FIXUP, \ + " .dword 4b,5b\n" TENTRY) + +#define __asm_clear_8(to, ret) \ + __asm_clear_8x_cont(to, ret, "", "", "") + +#define __asm_clear_12x_cont(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm_clear_8x_cont(to, ret, \ + " clear.d [%0+]\n6:\n" CLEAR, \ + "7: addq 4,%1\n" FIXUP, \ + " .dword 6b,7b\n" TENTRY) + +#define __asm_clear_12(to, ret) \ + __asm_clear_12x_cont(to, ret, "", "", "") + +#define __asm_clear_16x_cont(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm_clear_12x_cont(to, ret, \ + " clear.d [%0+]\n8:\n" CLEAR, \ + "9: addq 4,%1\n" FIXUP, \ + " .dword 8b,9b\n" TENTRY) + +#define __asm_clear_16(to, ret) \ + __asm_clear_16x_cont(to, ret, "", "", "") + +#define __asm_clear_20x_cont(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm_clear_16x_cont(to, ret, \ + " clear.d [%0+]\n10:\n" CLEAR, \ + "11: addq 4,%1\n" FIXUP, \ + " .dword 10b,11b\n" TENTRY) + +#define __asm_clear_20(to, ret) \ + __asm_clear_20x_cont(to, ret, "", "", "") + +#define __asm_clear_24x_cont(to, ret, CLEAR, FIXUP, TENTRY) \ + __asm_clear_20x_cont(to, ret, \ + " clear.d [%0+]\n12:\n" CLEAR, \ + "13: addq 4,%1\n" FIXUP, \ + " .dword 12b,13b\n" TENTRY) + +#define __asm_clear_24(to, ret) \ + __asm_clear_24x_cont(to, ret, "", "", "") + +/* + * Return the size of a string (including the ending 0) + * + * Return length of string in userspace including terminating 0 + * or 0 for error. Return a value greater than N if too long. + */ + +extern inline long +strnlen_user(const char *s, long n) +{ + long res, tmp1; + + if (!access_ok(VERIFY_READ, s, 0)) + return 0; + + /* + * This code is deduced from: + * + * tmp1 = n; + * while (tmp1-- > 0 && *s++) + * ; + * + * res = n - tmp1; + * + * (with tweaks). + */ + + __asm__ __volatile__ ( + " move.d %1,$r9\n" + "0:\n" + " ble 1f\n" + " subq 1,$r9\n" + + " test.b [%0+]\n" + " bne 0b\n" + " test.d $r9\n" + "1:\n" + " move.d %1,%0\n" + " sub.d $r9,%0\n" + "2:\n" + " .section .fixup,\"ax\"\n" + + "3: clear.d %0\n" + " jump 2b\n" + + /* There's one address for a fault at the first move, and + two possible PC values for a fault at the second move, + being a delay-slot filler. However, the branch-target + for the second move is the same as the first address. + Just so you don't get confused... */ + " .previous\n" + " .section __ex_table,\"a\"\n" + " .dword 0b,3b\n" + " .dword 1b,3b\n" + " .previous\n" + : "=r" (res), "=r" (tmp1) + : "0" (s), "1" (n) + : "r9"); + + return res; +} + +#endif |