| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Just like strncpy() except that if a fault occurs during copying, |
| * -EFAULT is returned. |
| * |
| * Inputs: |
| * in0: address of destination buffer |
| * in1: address of string to be copied |
| * in2: length of buffer in bytes |
| * Outputs: |
| * r8: -EFAULT in case of fault or number of bytes copied if no fault |
| * |
| * Copyright (C) 1998-2001 Hewlett-Packard Co |
| * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com> |
| * |
| * 00/03/06 D. Mosberger Fixed to return proper return value (bug found by |
| * by Andreas Schwab <schwab@suse.de>). |
| */ |
| |
| #include <linux/export.h> |
| #include <asm/asmmacro.h> |
| |
| GLOBAL_ENTRY(__strncpy_from_user) |
| alloc r2=ar.pfs,3,0,0,0 |
| mov r8=0 |
| mov r9=in1 |
| ;; |
| add r10=in1,in2 |
| cmp.eq p6,p0=r0,in2 |
| (p6) br.ret.spnt.many rp |
| |
| // XXX braindead copy loop---this needs to be optimized |
| .Loop1: |
| EX(.Lexit, ld1 r8=[in1],1) |
| ;; |
| EX(.Lexit, st1 [in0]=r8,1) |
| cmp.ne p6,p7=r8,r0 |
| ;; |
| (p6) cmp.ne.unc p8,p0=in1,r10 |
| (p8) br.cond.dpnt.few .Loop1 |
| ;; |
| (p6) mov r8=in2 // buffer filled up---return buffer length |
| (p7) sub r8=in1,r9,1 // return string length (excluding NUL character) |
| [.Lexit:] |
| br.ret.sptk.many rp |
| END(__strncpy_from_user) |
| EXPORT_SYMBOL(__strncpy_from_user) |
