mmap64: use INLINE_SYSCALL() helper fails for ppc

[Khem Raj]

On Wed, Apr 25, 2012 at 8:35 AM, Bernhard Reutner-Fischer
<rep.dot.nop at gmail.com> wrote:
> On 25 April 2012 17:27, Mike Frysinger <vapier at gentoo.org> wrote:
>> On Thursday 12 April 2012 19:43:44 Mike Frysinger wrote:
>>> On Thursday 12 April 2012 19:38:08 Khem Raj wrote:
>>> > I am seeing build failure on ppc
>>> >
>>> > | libc/libc_so.a(mmap64.os): In function `mmap64':
>>> > |
>>> > | /home/kraj/work/openembedded-core/build/tmp-uclibc/work/ppc603e-oe-linu
>>> > | x-
>>>
>>> uclibc/uclibc-0.9.33+gitra7c4e889e9c36fc19198654ada229aaa11955ee6-
>>>
>>> r6.0/git/libc/sysdeps/linux/common/mmap64.c:60:
>>> > undefined reference to `__illegally_sized_syscall_arg6'
>>> >
>>> > | collect2: error: ld returned 1 exit status
>>> >
>>> > It could be related to
>>> >
>>> > Author: Mike Frysinger <vapier at gentoo.org>
>>> > Date:   Wed Apr 11 16:05:08 2012 -0400
>>> >
>>> >     mmap64: use INLINE_SYSCALL() helper
>>>
>>> i was assuming INLINE_SYSCALL() would implicitly cast down the sizes, but i
>>> guess this is kind of better ... it forces you to add casts when you know
>>> it's ok, but errors out when you missed something.
>>>
>>> i'll commit a fix shortly (just to case it down to 32bits).
>>
>> how about this ?  not sure if there is a native type laying around to do what
>> i want ...
>
> That should work. Khem?
>
> thanks,
>> -mike
>>
>> --- a/libc/sysdeps/linux/common/mmap64.c
>> +++ b/libc/sysdeps/linux/common/mmap64.c
>> @@ -50,6 +50,16 @@ __ptr_t mmap64(__ptr_t addr, size_t len, int prot, int flags, int fd, __off64_t
>>
>>  __ptr_t mmap64(__ptr_t addr, size_t len, int prot, int flags, int fd, __off64_t offset)
>>  {
>> +       /*
>> +        * Some arches check the size in INLINE_SYSCALL() and barf if it's
>> +        * too big (i.e. a 64bit value getting truncated to 32bit).
>> +        */
>> +#  if __WORDSIZE == 32
>> +       uint32_t sys_offset;
>> +#  else
>> +       uint64_t sys_offset;
>> +#  endif
>> +
>>        if (offset & ((1 << MMAP2_PAGE_SHIFT) - 1)) {
>>                __set_errno(EINVAL);
>>                return MAP_FAILED;
>> @@ -61,8 +71,10 @@ __ptr_t mmap64(__ptr_t addr, size_t len, int prot, int flags, int fd, __off64_t
>>         * sign extend things and pass in the wrong value.  So cast it to
>>         * an unsigned 64-bit value before doing the shift.
>>         */
>> +       sys_offset = (uint64_t)offset >> MMAP2_PAGE_SHIFT;
>> +
>>        return (__ptr_t) INLINE_SYSCALL(mmap2, 6, addr, len, prot, flags, fd,
>> -                                       ((uint64_t)offset >> MMAP2_PAGE_SHIFT));
>> +                                       sys_offset);
>>  }
>>
>>  # endif

Looks ok. I cant try it out right now but may be later today