The statx manpage [1] shows that it has been supported from Linux 4.11
and glibc 2.28, the Linux support can be checked for all of the
architectures with this command:

    $ git grep -r statx v4.11 arch/ include/uapi/asm-generic/unistd.h \
      | grep -E "aarch64|arm|mips|s390|x86|:include/uapi"

Besides riscv and loongarch, all of the nolibc supported architectures
have added sys_statx from Linux v4.11. riscv is mainlined to v4.15,
loongarch is mainlined to v5.19, both of them use the generic unistd.h,
so, they have added sys_statx from their first mainline versions.

The current oldest stable branch is v4.14, only reserving sys_statx
still preserves compatibility with all of the supported stable branches,
So, let's remove the old arch related and dependent sys_stat support
completely.

This is friendly to the future new architecture porting.

[1]: https://man7.org/linux/man-pages/man2/statx.2.html

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

Both glibc and musl provide RB_ flags via <sys/reboot.h> for reboot(),
they don't need to include <linux/reboot.h>, let nolibc provide RB_
flags too.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

Do several cleanups together:

- Since all supported architectures have my_syscall6() now, remove the
  #ifdef check.

- Move the mmap() related macros to tools/include/nolibc/types.h and
  reuse most of them from <linux/mman.h>

- Apply the new generic __sysret() to convert the calling of sys_map()
  to oneline code

Note, since MAP_FAILED is -1 on Linux, so we can use the generic
__sysret() which returns -1 upon error and still satisfy user land that
checks for MAP_FAILED.

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230702192347.GJ16233@1wt.eu/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

Keep backwards compatibility through unions.

The compatibility macros like

 #define st_atime st_atim.tv_sec

as documented in stat(3type) don't work for nolibc because it would
break with other stat-like structures that contain the field st_atime.

The stx_atime, stx_mtime, stx_ctime are in type of 'struct
statx_timestamp', which is incompatible with 'struct timespec', should
be converted explicitly.

    /* include/uapi/linux/stat.h */

    struct statx_timestamp {
    	__s64	tv_sec;
    	__u32	tv_nsec;
    	__s32	__reserved;
    };

    /* include/uapi/linux/time.h */
    struct timespec {
    	__kernel_old_time_t	tv_sec;		/* seconds */
    	long			tv_nsec;	/* nanoseconds */
    };

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/linux-riscv/3a3edd48-1ace-4c89-89e8-9c594dd1b3c9@t-8ch.de/
Co-authored-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
[wt: squashed Zhangjin & Thomas' patches into one to preserve "bisectability"]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The same constants and some more have been exposed to userspace via
linux/reboot.h for a long time.

To avoid conflicts and trim down nolibc a bit drop the custom
definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

These are useful for users and will also be used in an upcoming
testcase.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Include linux/fcntl.h for O_* and AT_*. asm/fcntl.h is included
by linux/fcntl.h, so it can be safely removed.

Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

Defining S_I* flags in types.h can cause some build failures if
linux/stat.h is included prior to it. But if not defined, some toolchains
that include some glibc parts will in turn fail because linux/stat.h
already takes care of avoiding these definitions when glibc is present.

Let's preserve the macros here but first include linux/stat.h and check
for their definition before doing so. We also define the previously
missing permission macros so that we don't get a different behavior
depending on the first include found.

Cc: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

After the nolibc includes were split to facilitate portability from
standard libcs, programs that include only what they need may miss
some symbols which are needed by libgcc. This is the case for raise()
which is needed by the divide by zero code in some architectures for
example.

Regardless, being able to include only the apparently needed files is
convenient.

Instead of trying to move all exported definitions to a single file,
since this can change over time, this patch takes another approach
consisting in including the nolibc header at the end of all standard
include files. This way their types and functions are already known
at the moment of inclusion, and including any single one of them is
sufficient to bring all the required ones.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

The mode field has the type encoded as an value in a field, not as a bit
mask. Mask the mode with S_IFMT instead of each type to test. Otherwise,
false positives are possible: eg S_ISDIR will return true for block
devices because S_IFDIR = 0040000 and S_IFBLK = 0060000 since mode is
masked with S_IFDIR instead of S_IFMT. These macros now match the
similar definitions in tools/include/uapi/linux/stat.h.

Signed-off-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>