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Re: [PATCH v5 00/14] port C-SKY to glibc
On Wed, Nov 21, 2018 at 05:01:32PM +0000, Joseph Myers wrote:
> On Wed, 21 Nov 2018, Mao Han wrote:
>
> > I'v modified patch 14/14 to a generic version with __NR3264_fstatat
> > conditionals (in the attachment). It is tested in the same environment
> > as patch V5 and got same result, but have't test fstat64 path yet.
>
> Thanks, this is the sort of thing I'm looking for, but I'm concerned about
> the use of __NR3264_fstatat. As I understand, that's an internal
> implementation detail of the asm-generic unistd.h; it shouldn't be
> considered something stable that will reliably be there in future kernel
> versions. Rather, the stable interface from asm/unistd.h is the
> __NR_<syscall> macros for each <syscall> provided by the kernel. So I
> think the #ifdef conditionals need to be on the actual syscalls used in
> each case (e.g. you'd condition on __NR_fstat64 when using fstat64 in the
> existing INLINE_SYSCALL use). In statx_cp.c you'll need to find some stat
> syscall to condition on that's present on all existing architectures, as
> the aim is that no existing glibc architecture should get any code
> compiled from that file (which you could check using
> build-many-glibcs.py).
Yes. __NR_<syscall> macros should be used here. I'v change __NR3264_fstat*
to __NR_fstat*.
Current unistd.h alway have __NR_fstatat64 defined to __NR3264_fstatat
for 32-bit platform, so I used __NR3264_fstatat to make conditionals
work. As Arnd said that __NR3264_fstatat and the related macro will be
gone in 4.20 and the patch is not forwarded yet, C-SKY will get some
compile error with current kernel header, I added some conditionals
in unistd.h for test:
+#if defined(__ARCH_WANT_NEW_STAT) || defined(__ARCH_WANT_STAT64)
#define __NR_fstatat64 __NR3264_fstatat
#define __NR_fstat64 __NR3264_fstat
+#endif
Current statx_cp.c will check __NR_fstat64, __NR_fstatat64, __WORDSIZE == 32
to see if it is a 32 bit platforms without fstat64; __NR_fstat and
__NR_newfstatat check is for mips64-*-n32 and x86_64-*-x32 they always use
64 bit system call but got __WORDSIZE == 32.
I'v add an #error in statx_cp.c while using build-many-glibcs.py to do
the build test. Seems no other arch compiled code inside statx_cp.c
> Also, it's a bad idea to duplicate the contents of
> sysdeps/unix/sysv/linux/fxstat64.c in
> sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat64.c - rather, keep the
> existing #include, and modify sysdeps/unix/sysv/linux/fxstat64.c
> appropriately to handle the statx case (which definitely requires using
> __NR_fstat64 in the #ifdef, since this file is used in cases not using the
> asm-generic syscall list at all).
>
OK. I've modified sysdeps/unix/sysv/linux/fxstat64.c directly. I was quite
hesitate to change that file as it will affect more arch.
> You're using AT_NO_AUTOMOUNT in these statx calls - does that match what
> the old stat syscalls do on other architectures? (I think the aim there
> should be to match the old stat syscalls, so if those don't automount for
> stat of an automount point, then using AT_NO_AUTOMOUNT is correct.)
AT_NO_AUTOMOUNT is from ./include/linux/fs.h in the kernel. fstatat64
will call vfs_fstatat and fstat64 will call vfs_stat; they both got
AT_NO_AUTOMOUNT inside in call.
static inline int vfs_stat(const char __user *filename, struct kstat *stat)
{
return vfs_statx(AT_FDCWD, filename, AT_NO_AUTOMOUNT,
stat, STATX_BASIC_STATS);
}
static inline int vfs_fstatat(int dfd, const char __user *filename,
struct kstat *stat, int flags)
{
return vfs_statx(dfd, filename, flags | AT_NO_AUTOMOUNT,
stat, STATX_BASIC_STATS);
}
Best Regards,
Mao Han
>From d1a3b0fc2cd91f7a969468fd28c7eef27a2359c6 Mon Sep 17 00:00:00 2001
Message-Id: <d1a3b0fc2cd91f7a969468fd28c7eef27a2359c6.1542960800.git.han_mao@c-sky.com>
From: Mao Han <han_mao@c-sky.com>
Date: Fri, 23 Nov 2018 15:46:20 +0800
Subject: [PATCH V2 1/1] Add statx conditionals for wordsize-32 *xstat.c
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/generic/wordsize-32/fxstat.c: Add
conditionals for kernel without stat64.
* sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat64.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat64.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/statx_cp.c: New file.
* sysdeps/unix/sysv/linux/statx_cp.h: Likewise.
---
sysdeps/unix/sysv/linux/Makefile | 3 +-
sysdeps/unix/sysv/linux/fxstat64.c | 13 +++-
sysdeps/unix/sysv/linux/fxstatat64.c | 11 +++
.../unix/sysv/linux/generic/wordsize-32/fxstat.c | 11 +++
.../unix/sysv/linux/generic/wordsize-32/fxstatat.c | 11 +++
.../unix/sysv/linux/generic/wordsize-32/lxstat.c | 11 +++
.../unix/sysv/linux/generic/wordsize-32/lxstat64.c | 19 +++++-
.../unix/sysv/linux/generic/wordsize-32/xstat.c | 10 +++
.../unix/sysv/linux/generic/wordsize-32/xstat64.c | 14 +++-
sysdeps/unix/sysv/linux/statx_cp.c | 78 ++++++++++++++++++++++
sysdeps/unix/sysv/linux/statx_cp.h | 23 +++++++
11 files changed, 199 insertions(+), 5 deletions(-)
create mode 100644 sysdeps/unix/sysv/linux/statx_cp.c
create mode 100644 sysdeps/unix/sysv/linux/statx_cp.h
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 72b6b64..2943a10 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -177,7 +177,8 @@ sysdep_routines += xstatconv internal_statvfs internal_statvfs64 \
close_nocancel fcntl_nocancel nanosleep_nocancel \
open_nocancel open64_nocancel \
openat_nocancel openat64_nocancel \
- pause_nocancel read_nocancel waitpid_nocancel write_nocancel
+ pause_nocancel read_nocancel waitpid_nocancel \
+ write_nocancel statx_cp
sysdep_headers += bits/fcntl-linux.h
diff --git a/sysdeps/unix/sysv/linux/fxstat64.c b/sysdeps/unix/sysv/linux/fxstat64.c
index 0d05389..e2e51dc 100644
--- a/sysdeps/unix/sysv/linux/fxstat64.c
+++ b/sysdeps/unix/sysv/linux/fxstat64.c
@@ -1,4 +1,4 @@
-/* fxstat64 using Linux fstat64 system call.
+/* fxstat64 using Linux fstat64/statx system call.
Copyright (C) 1997-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
@@ -18,6 +18,7 @@
#include <errno.h>
#include <stddef.h>
+#include <fcntl.h>
#include <sys/stat.h>
#include <kernel_stat.h>
@@ -26,13 +27,23 @@
#include <kernel-features.h>
+#include "statx_cp.h"
+
/* Get information about the file FD in BUF. */
int
___fxstat64 (int vers, int fd, struct stat64 *buf)
{
int result;
+#ifdef __NR_fstat64
result = INLINE_SYSCALL (fstat64, 2, fd, buf);
+#else
+ struct statx tmp;
+ result = INLINE_SYSCALL (statx, 5, fd, "", AT_EMPTY_PATH, STATX_BASIC_STATS,
+ &tmp);
+ if (result == 0)
+ __cp_stat64_statx (buf, &tmp);
+#endif
#if defined _HAVE_STAT64___ST_INO && !__ASSUME_ST_INO_64_BIT
if (__builtin_expect (!result, 1) && buf->__st_ino != (__ino_t) buf->st_ino)
buf->st_ino = buf->__st_ino;
diff --git a/sysdeps/unix/sysv/linux/fxstatat64.c b/sysdeps/unix/sysv/linux/fxstatat64.c
index baa9a60..95123ed 100644
--- a/sysdeps/unix/sysv/linux/fxstatat64.c
+++ b/sysdeps/unix/sysv/linux/fxstatat64.c
@@ -26,6 +26,8 @@
#include <sysdep.h>
#include <sys/syscall.h>
+#include "statx_cp.h"
+
/* Get information about the file NAME in BUF. */
int
@@ -37,7 +39,16 @@ __fxstatat64 (int vers, int fd, const char *file, struct stat64 *st, int flag)
int result;
INTERNAL_SYSCALL_DECL (err);
+#ifdef __NR_fstatat64
result = INTERNAL_SYSCALL (fstatat64, err, 4, fd, file, st, flag);
+#else
+ struct statx tmp;
+
+ result = INTERNAL_SYSCALL (statx, err, 5, fd, file, AT_NO_AUTOMOUNT | flag,
+ STATX_BASIC_STATS, &tmp);
+ if (result == 0)
+ __cp_stat64_statx (st, &tmp);
+#endif
if (!__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 1))
return 0;
else
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat.c
index b5c766d..0c0ff10 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat.c
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstat.c
@@ -18,6 +18,7 @@
#include <errno.h>
#include <stddef.h>
+#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <kernel_stat.h>
@@ -27,6 +28,7 @@
#if !XSTAT_IS_XSTAT64
#include "overflow.h"
+#include "statx_cp.h"
/* Get information about the file FD in BUF. */
int
@@ -34,8 +36,17 @@ __fxstat (int vers, int fd, struct stat *buf)
{
if (vers == _STAT_VER_KERNEL)
{
+# ifdef __NR_fstat64
int rc = INLINE_SYSCALL (fstat64, 2, fd, buf);
return rc ?: stat_overflow (buf);
+# else
+ struct statx tmp;
+ int rc = INLINE_SYSCALL (statx, 5, fd, "", AT_EMPTY_PATH,
+ STATX_BASIC_STATS, &tmp);
+ if (rc == 0)
+ __cp_stat_statx (buf, &tmp);
+ return rc;
+# endif
}
errno = EINVAL;
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat.c
index 0bda8f7..58e3a90 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat.c
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/fxstatat.c
@@ -28,6 +28,7 @@
#if !XSTAT_IS_XSTAT64
#include "overflow.h"
+#include "statx_cp.h"
/* Get information about the file NAME in BUF. */
int
@@ -35,8 +36,18 @@ __fxstatat (int vers, int fd, const char *file, struct stat *buf, int flag)
{
if (vers == _STAT_VER_KERNEL)
{
+# ifdef __NR_fstatat64
int rc = INLINE_SYSCALL (fstatat64, 4, fd, file, buf, flag);
return rc ?: stat_overflow (buf);
+# else
+ struct statx tmp;
+ int rc = INLINE_SYSCALL (statx, 5, fd, file,
+ AT_NO_AUTOMOUNT | flag,
+ STATX_BASIC_STATS, &tmp);
+ if (rc == 0)
+ __cp_stat_statx (buf, &tmp);
+ return rc;
+# endif
}
errno = EINVAL;
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat.c
index c278a4d..b680782 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat.c
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat.c
@@ -27,6 +27,7 @@
#if !XSTAT_IS_XSTAT64
#include "overflow.h"
+#include "statx_cp.h"
/* Get information about the file NAME in BUF. */
int
@@ -34,9 +35,19 @@ __lxstat (int vers, const char *name, struct stat *buf)
{
if (vers == _STAT_VER_KERNEL)
{
+#ifdef __NR_fstatat64
int rc = INLINE_SYSCALL (fstatat64, 4, AT_FDCWD, name, buf,
AT_SYMLINK_NOFOLLOW);
return rc ?: stat_overflow (buf);
+#else
+ struct statx tmp;
+ int rc = INLINE_SYSCALL (statx, 5, AT_FDCWD, name,
+ AT_NO_AUTOMOUNT | AT_SYMLINK_NOFOLLOW,
+ STATX_BASIC_STATS, &tmp);
+ if (rc == 0)
+ __cp_stat_statx (buf, &tmp);
+ return rc;
+#endif
}
errno = EINVAL;
return -1;
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat64.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat64.c
index 761dd16..c41c759 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat64.c
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/lxstat64.c
@@ -32,13 +32,28 @@
#include <sysdep.h>
#include <sys/syscall.h>
+#include "statx_cp.h"
+
/* Get information about the file NAME in BUF. */
int
__lxstat64 (int vers, const char *name, struct stat64 *buf)
{
if (vers == _STAT_VER_KERNEL)
- return INLINE_SYSCALL (fstatat64, 4, AT_FDCWD, name, buf,
- AT_SYMLINK_NOFOLLOW);
+ {
+#ifdef __NR_fstatat64
+ return INLINE_SYSCALL (fstatat64, 4, AT_FDCWD, name, buf,
+ AT_SYMLINK_NOFOLLOW);
+#else
+ struct statx tmp;
+ int rc = INLINE_SYSCALL (statx, 5, AT_FDCWD, name,
+ AT_NO_AUTOMOUNT | AT_SYMLINK_NOFOLLOW,
+ STATX_BASIC_STATS, &tmp);
+ if (rc == 0)
+ __cp_stat64_statx (buf, &tmp);
+ return rc;
+#endif
+ }
+
errno = EINVAL;
return -1;
}
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat.c
index 1fd57ff..b67f4bb 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat.c
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat.c
@@ -27,6 +27,7 @@
#if !XSTAT_IS_XSTAT64
#include "overflow.h"
+#include "statx_cp.h"
/* Get information about the file NAME in BUF. */
int
@@ -34,8 +35,17 @@ __xstat (int vers, const char *name, struct stat *buf)
{
if (vers == _STAT_VER_KERNEL)
{
+# ifdef __NR_fstatat64
int rc = INLINE_SYSCALL (fstatat64, 4, AT_FDCWD, name, buf, 0);
return rc ?: stat_overflow (buf);
+# else
+ struct statx tmp;
+ int rc = INLINE_SYSCALL (statx, 5, AT_FDCWD, name, AT_NO_AUTOMOUNT,
+ STATX_BASIC_STATS, &tmp);
+ if (rc == 0)
+ __cp_stat_statx (buf, &tmp);
+ return rc;
+# endif
}
errno = EINVAL;
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat64.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat64.c
index ae70495..209675e 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat64.c
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/xstat64.c
@@ -32,13 +32,25 @@
#include <sysdep.h>
#include <sys/syscall.h>
+#include "statx_cp.h"
+
/* Get information about the file NAME in BUF. */
int
__xstat64 (int vers, const char *name, struct stat64 *buf)
{
if (vers == _STAT_VER_KERNEL)
+ {
+#ifdef __NR_fstatat64
return INLINE_SYSCALL (fstatat64, 4, AT_FDCWD, name, buf, 0);
-
+#else
+ struct statx tmp;
+ int rc = INLINE_SYSCALL (statx, 5, AT_FDCWD, name, AT_NO_AUTOMOUNT,
+ STATX_BASIC_STATS, &tmp);
+ if (rc == 0)
+ __cp_stat64_statx (buf, &tmp);
+ return rc;
+#endif
+ }
errno = EINVAL;
return -1;
}
diff --git a/sysdeps/unix/sysv/linux/statx_cp.c b/sysdeps/unix/sysv/linux/statx_cp.c
new file mode 100644
index 0000000..f31f5da4
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/statx_cp.c
@@ -0,0 +1,78 @@
+/* Struct statx to stat/stat64 conversion for Linux.
+ Copyright (C) 2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <stddef.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <kernel_stat.h>
+
+#include <sysdep.h>
+#include <sys/syscall.h>
+
+#if !defined(__NR_fstat64) && !defined(__NR_fstatat64) && __WORDSIZE == 32 \
+ && !defined(__NR_fstat) && !defined(__NR_newfstatat)
+void
+__cp_stat_statx (struct stat *to, struct statx *from)
+{
+ memset(to, 0, sizeof(struct stat));
+ to->st_dev = ((from->stx_dev_minor & 0xff) | (from->stx_dev_major << 8)
+ | ((from->stx_dev_minor & ~0xff) << 12));
+ to->st_rdev = ((from->stx_rdev_minor & 0xff) | (from->stx_rdev_major << 8)
+ | ((from->stx_rdev_minor & ~0xff) << 12));
+ to->st_ino = from->stx_ino;
+ to->st_mode = from->stx_mode;
+ to->st_nlink = from->stx_nlink;
+ to->st_uid = from->stx_uid;
+ to->st_gid = from->stx_gid;
+ to->st_atime = from->stx_atime.tv_sec;
+ to->st_atim.tv_nsec = from->stx_atime.tv_nsec;
+ to->st_mtime = from->stx_mtime.tv_sec;
+ to->st_mtim.tv_nsec = from->stx_mtime.tv_nsec;
+ to->st_ctime = from->stx_ctime.tv_sec;
+ to->st_ctim.tv_nsec = from->stx_ctime.tv_nsec;
+ to->st_size = from->stx_size;
+ to->st_blocks = from->stx_blocks;
+ to->st_blksize = from->stx_blksize;
+}
+
+void
+__cp_stat64_statx (struct stat64 *to, struct statx *from)
+{
+ memset(to, 0, sizeof(struct stat64));
+ to->st_dev = ((from->stx_dev_minor & 0xff) | (from->stx_dev_major << 8)
+ | ((from->stx_dev_minor & ~0xff) << 12));
+ to->st_rdev = ((from->stx_rdev_minor & 0xff) | (from->stx_rdev_major << 8)
+ | ((from->stx_rdev_minor & ~0xff) << 12));
+ to->st_ino = from->stx_ino;
+ to->st_mode = from->stx_mode;
+ to->st_nlink = from->stx_nlink;
+ to->st_uid = from->stx_uid;
+ to->st_gid = from->stx_gid;
+ to->st_atime = from->stx_atime.tv_sec;
+ to->st_atim.tv_nsec = from->stx_atime.tv_nsec;
+ to->st_mtime = from->stx_mtime.tv_sec;
+ to->st_mtim.tv_nsec = from->stx_mtime.tv_nsec;
+ to->st_ctime = from->stx_ctime.tv_sec;
+ to->st_ctim.tv_nsec = from->stx_ctime.tv_nsec;
+ to->st_size = from->stx_size;
+ to->st_blocks = from->stx_blocks;
+ to->st_blksize = from->stx_blksize;
+}
+#endif
diff --git a/sysdeps/unix/sysv/linux/statx_cp.h b/sysdeps/unix/sysv/linux/statx_cp.h
new file mode 100644
index 0000000..7e411a7
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/statx_cp.h
@@ -0,0 +1,23 @@
+/* Struct statx to stat/stat64 conversion for Linux.
+ Copyright (C) 2018 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
+ <http://www.gnu.org/licenses/>. */
+
+extern void __cp_stat_statx (struct stat *to, struct statx *from)
+ attribute_hidden;
+
+extern void __cp_stat64_statx (struct stat64 *to, struct statx *from)
+ attribute_hidden;
--
2.7.4