The LFS support is implemented on fxstat64.c, instead of fxstat.c for
64-bit architectures. The fxstatat.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 issues __NR_fstatat64 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, mips32,
microblaze, s390, sh, powerpc, and sparc32). it issues
__NR_fstatat64 and convert to non-LFS stat struct based on the
version.
Also non-LFS mips64 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 issues __NR_newfstatat for _STAT_VER_KERNEL or
_STAT_VER_LINUX.
1.2. 64-bit kABI outlier (sparc64): it issuess fstatat64 with a
temporary stat64 and convert to output stat64 based on the
input version (and using a sparc64 specific __xstat32_conv).
1.3. New 32-bit kABIs with only 64-bit time_t support (arc and
riscv32): it issues __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 uses the __NR_fstatat64 syscall instead.
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>
With all Linux ABIs using the expected Linux kABI to indicate
syscalls errors, the INTERNAL_SYSCALL_DECL is an empty declaration
on all ports.
This patch removes the 'err' argument on INTERNAL_SYSCALL* macro
and remove the INTERNAL_SYSCALL_DECL usage.
Checked with a build against all affected ABIs.
Linux kernel have remove stat64 family from default syscall set, new
implementations with statx is needed when __ARCH_WANT_STAT64 is not
define. This patch add conditionals for relevant functions, using statx
system call to get information and then copy to the return buf, ref to
include/linux/fs.h from linux kernel.
* sysdeps/unix/sysv/linux/Makefile: Add statx_cp.c.
* sysdeps/unix/sysv/linux/fxstat64.c: Add conditionals for kernel
without stat64 system call support.
* sysdeps/unix/sysv/linux/fxstatat64.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat64.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/xstat.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/xstat64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/statx_cp.c: New file.
* sysdeps/unix/sysv/linux/statx_cp.c: Likewise.
* sysdeps/unix/sysv/linux/statx_cp.h: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/statx_cp.c: Likewise.
This patch cleans up for __ASSUME_ATFCTS now always being true for the
supported Linux kernel versions by removing conditional code in
sysdeps/unix/sysv/linux. Several fchownat.c files that were only
present because of differences in the fallback syscalls used
(depending on the architecture-specific names of chown-related
syscalls for 32-bit uids) are removed. Files that looks like they
could be replaced by syscalls.list entries have the standard "Consider
moving to syscalls.list." comment (see bug 14138) added. Conditionals
on the relevant __NR_* syscall numbers being defined are also removed,
since my analysis indicated that the relevant syscalls are always
defined for all relevant kernel versions using any affected file.
Much of the removed fallback code had unbounded stack allocations, so
this reduces the number of cases to consider for anyone reviewing uses
of alloca and VLAs in glibc.
There remain tests of __ASSUME_ATFCTS in io/openat.c (to determine
whether to define __have_atfcts) and sysdeps/posix/getcwd.c (which
also uses __have_atfcts); thus, the definition of __ASSUME_ATFCTS
remains in kernel-features.h. The logical condition relevant there is
whether openat64_not_cancel_3 is known to work. Hurd doesn't use this
version of getcwd at all, so the conditionals in getcwd.c are always
true in glibc. However, this code is also used in gnulib. So the
best way to deal with the conditionals there may be for gnulib people
to deal with merging all relevant changes in both directions between
the glibc and gnulib versions of this file, at the end of which the
openat conditionals should be in whatever form is best for gnulib, and
hardcoded in the _LIBC case to having openat supported.
Tested by comparing before-and-after disassembly of installed
(stripped) shared libraries, on x86_64 and x86. On x86 the patch made
no change to the disassembly; on x86_64, the only changes were in
readlinkat, where formerly the return value from the readlinkat
syscall was stored in an int variable before being converted to
ssize_t for the return, and now the return value is returned directly
without truncation to int. I think it's clearly correct not to
truncate the return value (although I also think the truncation would
not have been a user-visible bug because the kernel would never have
returned a value it could have affected).
* include/fcntl.h (__atfct_seterrno): Remove prototype.
(__atfct_seterrno_2): Likewise.
* sysdeps/unix/sysv/linux/alpha/dl-fxstatat64.c: Do not include
<kernel-features.h>.
(__ASSUME_ATFCTS): Do not undefine and redefine.
* sysdeps/unix/sysv/linux/alpha/fxstatat.c [__ASSUME_ATFCTS]
(__have_atfcts): Remove conditional definition.
(__fxstatat([__NR_fstatat64]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code and code
unreachable if [__ASSUME_ATFCTS].
* sysdeps/unix/sysv/linux/dl-fxstatat64.c (__ASSUME_ATFCTS): Do
not undefine and redefine.
* sysdeps/unix/sysv/linux/faccessat.c: Do not include
<kernel-features.h>.
(faccessat) [__NR_faccessat]: Make code unconditional.
(faccessat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fchmodat.c: Do not include
<kernel-features.h>.
(fchmodat) [__NR_fchmodat]: Make code unconditional.
(fchmodat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fchownat.c: Do not include
<kernel-features.h>.
(fchownat) [__NR_fchownat]: Make code unconditional.
(fchownat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/futimesat.c: Do not include
<kernel-features.h>.
(futimesat) [__NR_futimesat]: Make code unconditional.
(futimesat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fxstatat.c: Do not include
<kernel-features.h>.
(__fxstatat) [__NR_newfstatat]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/fxstatat64.c: Do not include
<kernel-features.h>.
(__fxstatat64) [__NR_fstatat64]: Make code unconditional.
(__fxstatat64) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/i386/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/i386/fxstatat.c: Do not include
<kernel-features.h>.
(__fxstatat) [__NR_fstatat64]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/linkat.c: Do not include
<kernel-features.h>.
(linkat) [__NR_linkat]: Make code unconditional.
(linkat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/m68k/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/mips/mips64/fxstatat64.c: Do not include
<kernel-features.h>.
(__fxstatat64) [__NR_newfstatat]: Make code unconditional.
(__fxstatat64) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/mkdirat.c: Do not include
<kernel-features.h>.
(mkdirat) [__NR_mkdirat]: Make code unconditional.
(mkdirat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/openat.c: Do not include
<kernel-features.h>.
[!__ASSUME_ATFCTS] (__atfct_seterrno): Remove function.
[!__ASSUME_ATFCTS] (__have_atfcts): Remove variable.
(OPENAT_NOT_CANCEL) [__NR_openat]: Make code unconditional.
(OPENAT_NOT_CANCEL) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/powerpc/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/readlinkat.c: Do not include
<kernel-features.h>.
(readlinkat) [__NR_readlinkat]: Make code unconditional.
(readlinkat) [!__ASSUME_ATFCTS]: Remove conditional code. Return
result of INLINE_SYSCALL directly, not via int variable.
* sysdeps/unix/sysv/linux/renameat.c: Do not include
<kernel-features.h>.
[!__ASSUME_ATFCTS] (__atfct_seterrno_2): Remove function.
(renameat) [__NR_renameat]: Make code unconditional.
(renameat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/sh/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/sparc/sparc32/fchownat.c: Remove file.
* sysdeps/unix/sysv/linux/sparc/sparc64/dl-fxstatat64.c
(__ASSUME_ATFCTS): Do not undefine and redefine.
* sysdeps/unix/sysv/linux/symlinkat.c: Do not include
<kernel-features.h>.
(symlinkat) [__NR_symlinkat]: Make code unconditional.
(symlinkat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/unlinkat.c: Do not include
<kernel-features.h>.
(unlinkat) [__NR_unlinkat]: Make code unconditional.
(unlinkat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/wordsize-64/dl-fxstatat64.c
(__ASSUME_ATFCTS): Do not undefine and redefine.
* sysdeps/unix/sysv/linux/wordsize-64/fxstatat.c: Do not include
<kernel-features.h>.
(__fxstatat) [__NR_newfstatat]: Make code unconditional.
(__fxstatat) [!__ASSUME_ATFCTS]: Remove conditional code.
* sysdeps/unix/sysv/linux/xmknodat.c: Do not include
<kernel-features.h>.
(__xmknodat) [__NR_mknodat]: Make code unconditional.
(__xmknodat) [!__ASSUME_ATFCTS]: Remove conditional code.
fchownat, and unlinkat.
(static-only-routines): Add fstatat and fstatat64.
(tests): Add tst-unlinkat, tst-fstatat, tst-futimesat, tst-renameat,
and tst-fchownat.
* io/Versions [GLIBC_2.4]: Add fchownat, __fxstatat, __fxstatat64,
and unlinkat.
* io/fcntl.h: Define AT_FDCWD, AT_SYMLINK_NOFOLLOW, and AT_REMOVEDIR.
* io/fstatat.c: New file.
* io/fstatat64.c: New file.
* io/sys/stat.h: Declare fstatat, fstatat64, __fxstatat, __fxstatat64
and define fstatat and fstatat64 inline functions.
* libio/stdio.h: Declare renameat.
* misc/Makefile (routines): Add futimesat.
* misc/Versions [GLIBC_2.4]: Add futimesat.
* posix/unistd.h: Declare fchownat and unlinkat.
* stdio-common/Makefile (routines): Add renameat.
* stdio-common/Versions [GLIBC_2.4]: Add renameat.
* sysdeps/generic/fchownat.c: New file.
* sysdeps/generic/futimesat.c: New file.
* sysdeps/generic/fxstatat.c: New file.
* sysdeps/generic/fxstatat64.c: New file.
* sysdeps/generic/renameat.c: New file.
* sysdeps/generic/unlinkat.c: New file.
* sysdeps/unix/sysv/linux/fchownat.c: New file.
* sysdeps/unix/sysv/linux/futimesat.c: New file.
* sysdeps/unix/sysv/linux/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/fxstatat64.c: New file.
* sysdeps/unix/sysv/linux/renameat.c: New file.
* sysdeps/unix/sysv/linux/unlinkat.c: New file.
* sysdeps/unix/sysv/linux/alpha/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/i386/fchownat.c: New file.
* sysdeps/unix/sysv/linux/i386/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/m68k/fchownat.c: New file.
* sysdeps/unix/sysv/linux/m68k/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/powerpc/fchownat.c: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c: New file.
* sysdeps/unix/sysv/linux/s390/s390-32/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/sh/fchownat.c: New file.
* sysdeps/unix/sysv/linux/sh/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/fchownat.c: New file.
* sysdeps/unix/sysv/linux/sparc/sparc32/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/sparc/sparc64/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/wordsize-64/fxstatat.c: New file.
* sysdeps/unix/sysv/linux/wordsize-64/fxstatat64.c: New file.
* time/sys/time.h: Declare futimesat.
* include/fcntl.h: Declare __atfct_seterrno.
* sysdeps/unix/sysv/linux/openat.c (__atfct_seterrno): New function.
Split out from openat code and called.
(do_test): Allow openat to fail with ENOSYS. Handle AT_FDCWD.
* sysdeps/generic/openat.c: Handle AT_FDCWD.
* sysdeps/generic/openat64.c: Likewise.
* io/tst-unlinkat.c: New file.
* io/tst-fstatat.c: New file.
* io/tst-futimesat.c: New file.
* io/tst-renameat.c: New file.
* io/tst-fchownat.c: New file.
* io/tst-openat.c: Don't fail if openat is not implemented.
* sysdeps/unix/sysv/linux/powerpc/chown.c: Don't provide backward
compatibility code if new kernel is guaranteed.
* time/sys/time.h: Add a few nonnull attributes.
