| /* |
| * 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> |
| #include <linux/linkage.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) |
| */ |
| |
| ENTRY(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 |
| ENDPROC(lstrncpy_from_user) |
| |
| .section .fixup,"ax" |
| 3: fixup_branch $lsfu_exit |
| ldi -EFAULT,%r28 |
| .previous |
| |
| .section __ex_table,"aw" |
| ASM_ULONG_INSN 1b,3b |
| ASM_ULONG_INSN 2b,3b |
| .previous |
| |
| .procend |
| |
| /* |
| * unsigned long lclear_user(void *to, unsigned long n) |
| * |
| * Returns 0 for success. |
| * otherwise, returns number of bytes not transferred. |
| */ |
| |
| ENTRY(lclear_user) |
| .proc |
| .callinfo NO_CALLS |
| .entry |
| comib,=,n 0,%r25,$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 |
| ENDPROC(lclear_user) |
| |
| .section .fixup,"ax" |
| 2: fixup_branch $lclu_done |
| ldo 1(%r25),%r25 |
| .previous |
| |
| .section __ex_table,"aw" |
| ASM_ULONG_INSN 1b,2b |
| .previous |
| |
| .procend |
| |
| /* |
| * long lstrnlen_user(char *s, long n) |
| * |
| * Returns 0 if exception before zero byte or reaching N, |
| * N+1 if N would be exceeded, |
| * else strlen + 1 (i.e. includes zero byte). |
| */ |
| |
| ENTRY(lstrnlen_user) |
| .proc |
| .callinfo NO_CALLS |
| .entry |
| comib,= 0,%r25,$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 */ |
| ENDPROC(lstrnlen_user) |
| |
| .section .fixup,"ax" |
| 3: fixup_branch $lslen_done |
| copy %r24,%r26 /* reset r26 so 0 is returned on fault */ |
| .previous |
| |
| .section __ex_table,"aw" |
| ASM_ULONG_INSN 1b,3b |
| ASM_ULONG_INSN 2b,3b |
| .previous |
| |
| .procend |
| |
| .end |