1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun/* 3*4882a593Smuzhiyun * Just like strncpy() except that if a fault occurs during copying, 4*4882a593Smuzhiyun * -EFAULT is returned. 5*4882a593Smuzhiyun * 6*4882a593Smuzhiyun * Inputs: 7*4882a593Smuzhiyun * in0: address of destination buffer 8*4882a593Smuzhiyun * in1: address of string to be copied 9*4882a593Smuzhiyun * in2: length of buffer in bytes 10*4882a593Smuzhiyun * Outputs: 11*4882a593Smuzhiyun * r8: -EFAULT in case of fault or number of bytes copied if no fault 12*4882a593Smuzhiyun * 13*4882a593Smuzhiyun * Copyright (C) 1998-2001 Hewlett-Packard Co 14*4882a593Smuzhiyun * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com> 15*4882a593Smuzhiyun * 16*4882a593Smuzhiyun * 00/03/06 D. Mosberger Fixed to return proper return value (bug found by 17*4882a593Smuzhiyun * by Andreas Schwab <schwab@suse.de>). 18*4882a593Smuzhiyun */ 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun#include <asm/asmmacro.h> 21*4882a593Smuzhiyun#include <asm/export.h> 22*4882a593Smuzhiyun 23*4882a593SmuzhiyunGLOBAL_ENTRY(__strncpy_from_user) 24*4882a593Smuzhiyun alloc r2=ar.pfs,3,0,0,0 25*4882a593Smuzhiyun mov r8=0 26*4882a593Smuzhiyun mov r9=in1 27*4882a593Smuzhiyun ;; 28*4882a593Smuzhiyun add r10=in1,in2 29*4882a593Smuzhiyun cmp.eq p6,p0=r0,in2 30*4882a593Smuzhiyun(p6) br.ret.spnt.many rp 31*4882a593Smuzhiyun 32*4882a593Smuzhiyun // XXX braindead copy loop---this needs to be optimized 33*4882a593Smuzhiyun.Loop1: 34*4882a593Smuzhiyun EX(.Lexit, ld1 r8=[in1],1) 35*4882a593Smuzhiyun ;; 36*4882a593Smuzhiyun EX(.Lexit, st1 [in0]=r8,1) 37*4882a593Smuzhiyun cmp.ne p6,p7=r8,r0 38*4882a593Smuzhiyun ;; 39*4882a593Smuzhiyun(p6) cmp.ne.unc p8,p0=in1,r10 40*4882a593Smuzhiyun(p8) br.cond.dpnt.few .Loop1 41*4882a593Smuzhiyun ;; 42*4882a593Smuzhiyun(p6) mov r8=in2 // buffer filled up---return buffer length 43*4882a593Smuzhiyun(p7) sub r8=in1,r9,1 // return string length (excluding NUL character) 44*4882a593Smuzhiyun[.Lexit:] 45*4882a593Smuzhiyun br.ret.sptk.many rp 46*4882a593SmuzhiyunEND(__strncpy_from_user) 47*4882a593SmuzhiyunEXPORT_SYMBOL(__strncpy_from_user) 48