[PATCH 2/5] Linux: Define MMAP_CALL_INTERNAL

[Stefan Liebler]

On 03/05/2022 20:30, Florian Weimer wrote:
> * Florian Weimer via Libc-alpha:
> 
>> Unlike MMAP_CALL, this avoids a TCB dependency for an errno update
>> on failure.
>>
>> <mmap_internal.h> cannot be included as is on several architectures
>> due to the definition of page_unit, so introduce a separate header
>> file for the definition of MMAP_CALL and MMAP_CALL_INTERNAL,
>>  <mmap_call.h>.
>> ---
>>  sysdeps/unix/sysv/linux/mmap_call.h           | 22 +++++++++++++++++++
>>  sysdeps/unix/sysv/linux/mmap_internal.h       |  6 +----
>>  .../s390/{mmap_internal.h => mmap_call.h}     | 14 ++++++------
>>  3 files changed, 30 insertions(+), 12 deletions(-)
>>  create mode 100644 sysdeps/unix/sysv/linux/mmap_call.h
>>  rename sysdeps/unix/sysv/linux/s390/{mmap_internal.h => mmap_call.h} (78%)
>>
>> diff --git a/sysdeps/unix/sysv/linux/mmap_call.h b/sysdeps/unix/sysv/linux/mmap_call.h
>> new file mode 100644
>> index 0000000000..3547c99e14
>> --- /dev/null
>> +++ b/sysdeps/unix/sysv/linux/mmap_call.h
>> @@ -0,0 +1,22 @@
>> +/* Generic definition of MMAP_CALL and MMAP_CALL_INTERNAL.
>> +   Copyright (C) 2017-2022 Free Software Foundation, Inc.
>> +   This file is part of the GNU C Library.
>> +
>> +   The GNU C Library is free software; you can redistribute it and/or
>> +   modify it under the terms of the GNU Lesser General Public
>> +   License as published by the Free Software Foundation; either
>> +   version 2.1 of the License, or (at your option) any later version.
>> +
>> +   The GNU C Library 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
>> +   Lesser General Public License for more details.
>> +
>> +   You should have received a copy of the GNU Lesser General Public
>> +   License along with the GNU C Library; if not, see
>> +   <https://www.gnu.org/licenses/>.  */
>> +
>> +#define MMAP_CALL(__nr, __addr, __len, __prot, __flags, __fd, __offset) \
>> +  INLINE_SYSCALL_CALL (__nr, __addr, __len, __prot, __flags, __fd, __offset)
>> +#define MMAP_CALL_INTERNAL(__nr, __addr, __len, __prot, __flags, __fd, __offset) \
>> +  INTERNAL_SYSCALL_CALL (__nr, __addr, __len, __prot, __flags, __fd, __offset)
>> diff --git a/sysdeps/unix/sysv/linux/mmap_internal.h b/sysdeps/unix/sysv/linux/mmap_internal.h
>> index 841b731391..aebf97d064 100644
>> --- a/sysdeps/unix/sysv/linux/mmap_internal.h
>> +++ b/sysdeps/unix/sysv/linux/mmap_internal.h
>> @@ -42,10 +42,6 @@ static uint64_t page_unit;
>>  /* Do not accept offset not multiple of page size.  */
>>  #define MMAP_OFF_LOW_MASK  (MMAP2_PAGE_UNIT - 1)
>>  
>> -/* An architecture may override this.  */
>> -#ifndef MMAP_CALL
>> -# define MMAP_CALL(__nr, __addr, __len, __prot, __flags, __fd, __offset) \
>> -  INLINE_SYSCALL_CALL (__nr, __addr, __len, __prot, __flags, __fd, __offset)
>> -#endif
>> +#include <mmap_call.h>
>>  
>>  #endif /* MMAP_INTERNAL_LINUX_H  */
>> diff --git a/sysdeps/unix/sysv/linux/s390/mmap_internal.h b/sysdeps/unix/sysv/linux/s390/mmap_call.h
>> similarity index 78%
>> rename from sysdeps/unix/sysv/linux/s390/mmap_internal.h
>> rename to sysdeps/unix/sysv/linux/s390/mmap_call.h
>> index cc76ac9735..f169b8bab9 100644
>> --- a/sysdeps/unix/sysv/linux/s390/mmap_internal.h
>> +++ b/sysdeps/unix/sysv/linux/s390/mmap_call.h
>> @@ -16,9 +16,6 @@
>>     License along with the GNU C Library; if not, see
>>     <https://www.gnu.org/licenses/>.  */
>>  
>> -#ifndef MMAP_S390_INTERNAL_H
>> -# define MMAP_S390_INTERNAL_H
>> -
>>  #define MMAP_CALL(__nr, __addr, __len, __prot, __flags, __fd, __offset)	\
>>    ({									\
>>      long int __args[6] = { (long int) (__addr), (long int) (__len),	\
>> @@ -26,7 +23,10 @@
>>  			   (long int) (__fd), (long int) (__offset) };	\
>>      INLINE_SYSCALL_CALL (__nr, __args);					\
>>    })
>> -
>> -#include_next <mmap_internal.h>
>> -
>> -#endif
>> +#define MMAP_CALL_INTERNAL(__nr, __addr, __len, __prot, __flags, __fd, __offset)	\
>> +  ({									\
>> +    long int __args[6] = { (long int) (__addr), (long int) (__len),	\
>> +			   (long int) (__prot), (long int) (__flags),	\
>> +			   (long int) (__fd), (long int) (__offset) };	\
>> +    INTERNAL_SYSCALL_CALL (__nr, __args);				\
>> +  })
> 
> Stefan, would you be able to review this patch?  It's mostly an S390
> change, after all.
> 
> Thanks,
> Florian
> 

Sure. The patch looks good to me.
Moving the definition of MMAP_CALL is just a mechanical change. The
definition of MMAP_CALL_INTERNAL is similar and no other architecture
than s390x has its own definition of MMAP_CALL.
Thanks.

Reviewed-by: Stefan Liebler <stli@linux.ibm.com>