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linux: Consolidate fxstat{64}

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The LFS support is implemented on fxstat64.c, instead of fxstat.c for
64-bit architectures.  The fxstat.c implements the non-LFS and it is
a no-op for !XSTAT_IS_XSTAT64.

The generic non-LFS implementation handles two cases:

  1. New kABIs which uses generic pre 64-bit time Linux ABI (csky and
     nios): it issuess __NR_fstat64 plus handle the overflow on st_ino,
     st_size, or st_blocks.  It only handles _STAT_VER_KERNEL.

  2. Old KABIs with old non-LFS support (arm, i386, hppa, m68k,
     microblaze, s390, sh, powerpc, and sparc32).  For _STAT_VER_KERNEL
     it issues __NR_fstat, otherwise it calls __NR_fstat64 and convert
     to non-LFS stat struct and handle possible overflows on st_ino,
     st_size, or st_blocks.

Also non-LFS mips is an outlier and it has its own implementation since
_STAT_VER_LINUX requires a different conversion function (it uses the
kernel_stat as the sysissues argument since its exported ABI is
different than the kernel one for both non-LFS and LFS implementation).

The generic LFS implementation handles multiple cases:

  1. XSTAT_IS_XSTAT64 being 1:

    1.1. 64-bit kABI (aarch64, ia64, powerpc64*, s390x, riscv64, and
	 x86_64): it issuess __NR_fstat for _STAT_VER_KERNEL or
	 _STAT_VER_LINUX.

    1.2. Old 64-bit kABI with defines __NR_fstat64 instead of __NR_fstat
         (sparc64): it issues __NR_fstat for _STAT_VER_KERNEL or
         __NR_fstat64 and convert to struct stat64.

    1.3. New 32-bit kABIs with only 64-bit time_t support (arc and
	 riscv32): it issuess __NR_statx and covert to struct stat64.

  2. Old ABIs with XSTAT_IS_XSTAT64 being 0 (arm, csky, i386, hppa,
     m68k, microblaze, mips32, nios2, sh, powerpc32, and sparc32): it
     issues __NR_fstat64.

Also, two special cases requires specific implementations:

  1. alpha: it requires to handle _STAT_VER_KERNEL64 to issues
     __NR_fstat64 and use the kernel_stat with __NR_fstat otherwise.

  2. mips64: as for non-LFS implementation its ABIs differ from
     glibc exported one, which requires an specific conversion
     function to handle the kernel_stat.

Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
This commit is contained in:
Adhemerval Zanella
2020-07-15 16:34:47 +00:00
parent 4f40e6adc4
commit 5febe6a38f
18 changed files with 105 additions and 266 deletions
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42
sysdeps/unix/sysv/linux/mips/fxstat.c Normal file
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/* fxstat using old-style Unix stat system call.
Copyright (C) 1991-2020 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/>. */
#include <sys/stat.h>
#include <fcntl.h>
#include <kernel_stat.h>
#include <sysdep.h>
#include <xstatconv.h>
/* Get information about the file NAME in BUF. */
int
__fxstat (int vers, int fd, struct stat *buf)
{
switch (vers)
{
case _STAT_VER_KERNEL:
return INLINE_SYSCALL_CALL (fstat, fd, buf);
default:
{
struct kernel_stat kbuf;
int r = INTERNAL_SYSCALL_CALL (fstat, fd, &kbuf);
return r ?: __xstat_conv (vers, &kbuf, buf);
}
}
}
hidden_def (__fxstat)