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Diffstat (limited to 'arch/parisc/lib/lusercopy.S')
| -rw-r--r-- | arch/parisc/lib/lusercopy.S | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/arch/parisc/lib/lusercopy.S b/arch/parisc/lib/lusercopy.S new file mode 100644 index 00000000000..a0509855c9a --- /dev/null +++ b/arch/parisc/lib/lusercopy.S @@ -0,0 +1,193 @@ +/* + * User Space Access Routines + * + * Copyright (C) 2000-2002 Hewlett-Packard (John Marvin) + * Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org> + * Copyright (C) 2001 Matthieu Delahaye <delahaym at esiee.fr> + * Copyright (C) 2003 Randolph Chung <tausq with parisc-linux.org> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* + * These routines still have plenty of room for optimization + * (word & doubleword load/store, dual issue, store hints, etc.). + */ + +/* + * The following routines assume that space register 3 (sr3) contains + * the space id associated with the current users address space. + */ + + + .text + +#include <asm/assembly.h> +#include <asm/errno.h> + + /* + * get_sr gets the appropriate space value into + * sr1 for kernel/user space access, depending + * on the flag stored in the task structure. + */ + + .macro get_sr + mfctl %cr30,%r1 + ldw TI_SEGMENT(%r1),%r22 + mfsp %sr3,%r1 + or,<> %r22,%r0,%r0 + copy %r0,%r1 + mtsp %r1,%sr1 + .endm + + .macro fixup_branch lbl + ldil L%\lbl, %r1 + ldo R%\lbl(%r1), %r1 + bv %r0(%r1) + .endm + + /* + * long lstrncpy_from_user(char *dst, const char *src, long n) + * + * Returns -EFAULT if exception before terminator, + * N if the entire buffer filled, + * otherwise strlen (i.e. excludes zero byte) + */ + + .export lstrncpy_from_user,code +lstrncpy_from_user: + .proc + .callinfo NO_CALLS + .entry + comib,= 0,%r24,$lsfu_done + copy %r24,%r23 + get_sr +1: ldbs,ma 1(%sr1,%r25),%r1 +$lsfu_loop: + stbs,ma %r1,1(%r26) + comib,=,n 0,%r1,$lsfu_done + addib,<>,n -1,%r24,$lsfu_loop +2: ldbs,ma 1(%sr1,%r25),%r1 +$lsfu_done: + sub %r23,%r24,%r28 +$lsfu_exit: + bv %r0(%r2) + nop + .exit + + .section .fixup,"ax" +3: fixup_branch $lsfu_exit + ldi -EFAULT,%r28 + .previous + + .section __ex_table,"aw" +#ifdef __LP64__ + .dword 1b,3b + .dword 2b,3b +#else + .word 1b,3b + .word 2b,3b +#endif + .previous + + .procend + + /* + * unsigned long lclear_user(void *to, unsigned long n) + * + * Returns 0 for success. + * otherwise, returns number of bytes not transferred. + */ + + .export lclear_user,code +lclear_user: + .proc + .callinfo NO_CALLS + .entry + comib,=,n 0,%r25,$lclu_done + get_sr +$lclu_loop: + addib,<> -1,%r25,$lclu_loop +1: stbs,ma %r0,1(%sr1,%r26) + +$lclu_done: + bv %r0(%r2) + copy %r25,%r28 + .exit + + .section .fixup,"ax" +2: fixup_branch $lclu_done + ldo 1(%r25),%r25 + .previous + + .section __ex_table,"aw" +#ifdef __LP64__ + .dword 1b,2b +#else + .word 1b,2b +#endif + .previous + + .procend + + /* + * long lstrnlen_user(char *s, long n) + * + * Returns 0 if exception before zero byte or reaching N, + * N+1 if N would be exceeded, + * else strlen + 1 (i.e. includes zero byte). + */ + + .export lstrnlen_user,code +lstrnlen_user: + .proc + .callinfo NO_CALLS + .entry + comib,= 0,%r25,$lslen_nzero + copy %r26,%r24 + get_sr +1: ldbs,ma 1(%sr1,%r26),%r1 +$lslen_loop: + comib,=,n 0,%r1,$lslen_done + addib,<> -1,%r25,$lslen_loop +2: ldbs,ma 1(%sr1,%r26),%r1 +$lslen_done: + bv %r0(%r2) + sub %r26,%r24,%r28 + .exit + +$lslen_nzero: + b $lslen_done + ldo 1(%r26),%r26 /* special case for N == 0 */ + + .section .fixup,"ax" +3: fixup_branch $lslen_done + copy %r24,%r26 /* reset r26 so 0 is returned on fault */ + .previous + + .section __ex_table,"aw" +#ifdef __LP64__ + .dword 1b,3b + .dword 2b,3b +#else + .word 1b,3b + .word 2b,3b +#endif + .previous + + .procend + + .end |