diff options
Diffstat (limited to 'arch/ia64/lib/strncpy_from_user.S')
| -rw-r--r-- | arch/ia64/lib/strncpy_from_user.S | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/ia64/lib/strncpy_from_user.S b/arch/ia64/lib/strncpy_from_user.S new file mode 100644 index 000000000000..a504381f31eb --- /dev/null +++ b/arch/ia64/lib/strncpy_from_user.S @@ -0,0 +1,44 @@ +/* + * 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 <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) |