linux: Fix sys/mount.h usage with kernel headers
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Build for i686
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Commit Message
Now that kernel exports linux/mount.h and includes it on linux/fs.h,
its definitions might clash with glibc exports sys/mount.h. To avoid
the need to rearrange the Linux header to be always after glibc one,
the glibc sys/mount.h is changed to:
1. Undefine the macros also used as enum constants. This covers prior
inclusion of <linux/mount.h> (for instance MS_RDONLY).
2. Include <linux/mount.h> based on the usual __has_include check
(needs to use __has_include ("linux/mount.h") to paper over GCC
bugs.
3. Define enum fsconfig_command only if FSOPEN_CLOEXEC is not defined.
(FSOPEN_CLOEXEC should be a very close proxy.)
4. Define struct mount_attr if MOUNT_ATTR_SIZE_VER0 is not defined.
(Added in the same commit on the Linux side.)
5. Undefine some macros also used on linux/fs.h.
This patch also adds some tests to check if including linux/fs.h and
linux/mount.h after and before sys/mount.h does work.
Checked on x86_64-linux-gnu.
---
scripts/glibccompile.py | 45 +++++++++++
sysdeps/unix/sysv/linux/Makefile | 8 ++
sysdeps/unix/sysv/linux/sys/mount.h | 78 ++++++++++++++++++--
sysdeps/unix/sysv/linux/tst-mount-compile.py | 66 +++++++++++++++++
4 files changed, 189 insertions(+), 8 deletions(-)
create mode 100755 scripts/glibccompile.py
create mode 100755 sysdeps/unix/sysv/linux/tst-mount-compile.py
Comments
Hi,
Le 09/08/2022 à 19:22, Adhemerval Zanella via Libc-alpha a écrit :
> Now that kernel exports linux/mount.h and includes it on linux/fs.h,
> its definitions might clash with glibc exports sys/mount.h. To avoid
> the need to rearrange the Linux header to be always after glibc one,
> the glibc sys/mount.h is changed to:
>
> 1. Undefine the macros also used as enum constants. This covers prior
> inclusion of <linux/mount.h> (for instance MS_RDONLY).
>
> 2. Include <linux/mount.h> based on the usual __has_include check
> (needs to use __has_include ("linux/mount.h") to paper over GCC
> bugs.
>
> 3. Define enum fsconfig_command only if FSOPEN_CLOEXEC is not defined.
> (FSOPEN_CLOEXEC should be a very close proxy.)
>
> 4. Define struct mount_attr if MOUNT_ATTR_SIZE_VER0 is not defined.
> (Added in the same commit on the Linux side.)
>
> 5. Undefine some macros also used on linux/fs.h.
>
> This patch also adds some tests to check if including linux/fs.h and
> linux/mount.h after and before sys/mount.h does work.
For the record there's a change submitted today for review:
[RFC][PATCH] uapi: Remove the inclusion of linux/mount.h from
uapi/linux/fs.h <https://lore.kernel.org/linux-api/163410.1659964655@warthog.procyon.org.uk/#r>
https://lore.kernel.org/linux-api/163410.1659964655@warthog.procyon.org.uk/
Regards.
On 09/08/22 14:43, Yann Droneaud wrote:
> Hi,
>
> Le 09/08/2022 à 19:22, Adhemerval Zanella via Libc-alpha a écrit :
>> Now that kernel exports linux/mount.h and includes it on linux/fs.h,
>> its definitions might clash with glibc exports sys/mount.h. To avoid
>> the need to rearrange the Linux header to be always after glibc one,
>> the glibc sys/mount.h is changed to:
>>
>> 1. Undefine the macros also used as enum constants. This covers prior
>> inclusion of <linux/mount.h> (for instance MS_RDONLY).
>>
>> 2. Include <linux/mount.h> based on the usual __has_include check
>> (needs to use __has_include ("linux/mount.h") to paper over GCC
>> bugs.
>>
>> 3. Define enum fsconfig_command only if FSOPEN_CLOEXEC is not defined.
>> (FSOPEN_CLOEXEC should be a very close proxy.)
>>
>> 4. Define struct mount_attr if MOUNT_ATTR_SIZE_VER0 is not defined.
>> (Added in the same commit on the Linux side.)
>>
>> 5. Undefine some macros also used on linux/fs.h.
>>
>> This patch also adds some tests to check if including linux/fs.h and
>> linux/mount.h after and before sys/mount.h does work.
>
> For the record there's a change submitted today for review:
>
> [RFC][PATCH] uapi: Remove the inclusion of linux/mount.h from uapi/linux/fs.h <https://lore.kernel.org/linux-api/163410.1659964655@warthog.procyon.org.uk/#r>
>
> https://lore.kernel.org/linux-api/163410.1659964655@warthog.procyon.org.uk/
Thanks Yann, although I think we will still need to fix on glibc side
in case user do include linux/fs.h and/or linux/mount.h before
sys/mount.h.
* Adhemerval Zanella:
> diff --git a/scripts/glibccompile.py b/scripts/glibccompile.py
> new file mode 100755
> index 0000000000..3eb4e30cc4
> --- /dev/null
> +++ b/scripts/glibccompile.py
> @@ -0,0 +1,45 @@
> +#!/usr/bin/python3
> +# Provide functions to build code snippets.
> +# Copyright (C) 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/>.
> +
> +import os.path
> +import subprocess
> +import tempfile
> +import collections
> +
> +CompileResult = collections.namedtuple("CompileResult", "returncode output")
Convention is to use '' strings (outside doctext).
> +def compile_c_snippet(snippet, cc, extra_cc_args=""):
> + """Compile and return whether the SNIPPET can be build with CC along
> + EXTRA_CC_ARGS compiler flags. Return a CompileResult with RETURNCODE
> + being 0 for success, or the failure value and the compiler output.
> + """
> + with tempfile.TemporaryDirectory() as temp_dir:
> + c_file_name = os.path.join(temp_dir, 'test.c')
> + obj_file_name = os.path.join(temp_dir, 'test.o')
> + with open(c_file_name, 'w') as c_file:
> + c_file.write(snippet)
> + # Compilation has to be from stdin to avoid the temporary file
> + # name being written into the generated dependencies.
> + cmd = ('%s %s -c -o %s -x c - < %s' % (cc, extra_cc_args,
> + obj_file_name, c_file_name))
> + try:
> + return CompileResult(subprocess.run(cmd, shell=True,
> + capture_output=True, check=True).returncode, "")
> + except subprocess.SubprocessError as e:
> + return CompileResult(1, e.stderr)
It's a bit weird to use check=True and catch the exception.
Overall, this could probably go into glibcextract, and as a separate patch?
> diff --git a/sysdeps/unix/sysv/linux/sys/mount.h b/sysdeps/unix/sysv/linux/sys/mount.h
> index f965986ba8..ae8406838b 100644
> --- a/sysdeps/unix/sysv/linux/sys/mount.h
> +++ b/sysdeps/unix/sysv/linux/sys/mount.h
> @@ -27,6 +27,19 @@
> #include <stddef.h>
> #include <sys/ioctl.h>
>
> +#ifdef __has_include
> +# if __has_include ("linux/mount.h")
> +# include "linux/mount.h"
> +# ifdef FSOPEN_CLOEXEC
> +# define __mount_fsopen_cloexec_defined 1
> +# endif
> +# ifdef MOUNT_ATTR_SIZE_VER0
> +# define __mount_attr_size_ver0_defined 1
> +# endif
> +# endif
> +#endif
I think those __mount_ defines are not *that* useful.
> +
> +#undef BLOCK_SIZE
> #define BLOCK_SIZE 1024
If we don't have enum constants, should we #undef things? If we
redefine as the same token as the kernel, there won't be a preprocessor
warning.
Thanks,
Florian
On 10/08/22 06:23, Florian Weimer wrote:
> * Adhemerval Zanella:
>
>> diff --git a/scripts/glibccompile.py b/scripts/glibccompile.py
>> new file mode 100755
>> index 0000000000..3eb4e30cc4
>> --- /dev/null
>> +++ b/scripts/glibccompile.py
>> @@ -0,0 +1,45 @@
>> +#!/usr/bin/python3
>> +# Provide functions to build code snippets.
>> +# Copyright (C) 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/>.
>> +
>> +import os.path
>> +import subprocess
>> +import tempfile
>> +import collections
>> +
>> +CompileResult = collections.namedtuple("CompileResult", "returncode output")
>
> Convention is to use '' strings (outside doctext).
Ack, I will change it.
>
>> +def compile_c_snippet(snippet, cc, extra_cc_args=""):
>> + """Compile and return whether the SNIPPET can be build with CC along
>> + EXTRA_CC_ARGS compiler flags. Return a CompileResult with RETURNCODE
>> + being 0 for success, or the failure value and the compiler output.
>> + """
>> + with tempfile.TemporaryDirectory() as temp_dir:
>> + c_file_name = os.path.join(temp_dir, 'test.c')
>> + obj_file_name = os.path.join(temp_dir, 'test.o')
>> + with open(c_file_name, 'w') as c_file:
>> + c_file.write(snippet)
>> + # Compilation has to be from stdin to avoid the temporary file
>> + # name being written into the generated dependencies.
>> + cmd = ('%s %s -c -o %s -x c - < %s' % (cc, extra_cc_args,
>> + obj_file_name, c_file_name))
>> + try:
>> + return CompileResult(subprocess.run(cmd, shell=True,
>> + capture_output=True, check=True).returncode, "")
>> + except subprocess.SubprocessError as e:
>> + return CompileResult(1, e.stderr)
>
> It's a bit weird to use check=True and catch the exception.
Right, I think we can simplify to avoid the check=True and the exception
handling.
>
> Overall, this could probably go into glibcextract, and as a separate patch?
Alright, this sound feasible.
>
>> diff --git a/sysdeps/unix/sysv/linux/sys/mount.h b/sysdeps/unix/sysv/linux/sys/mount.h
>> index f965986ba8..ae8406838b 100644
>> --- a/sysdeps/unix/sysv/linux/sys/mount.h
>> +++ b/sysdeps/unix/sysv/linux/sys/mount.h
>> @@ -27,6 +27,19 @@
>> #include <stddef.h>
>> #include <sys/ioctl.h>
>>
>> +#ifdef __has_include
>> +# if __has_include ("linux/mount.h")
>> +# include "linux/mount.h"
>> +# ifdef FSOPEN_CLOEXEC
>> +# define __mount_fsopen_cloexec_defined 1
>> +# endif
>> +# ifdef MOUNT_ATTR_SIZE_VER0
>> +# define __mount_attr_size_ver0_defined 1
>> +# endif
>> +# endif
>> +#endif
>
> I think those __mount_ defines are not *that* useful.
Not sure I am following, should I remove them? If so it would require some more
ifdefs on their usage below.
>
>> +
>> +#undef BLOCK_SIZE
>> #define BLOCK_SIZE 1024
>
> If we don't have enum constants, should we #undef things? If we
> redefine as the same token as the kernel, there won't be a preprocessor
> warning.
This is required because of linux/fs.h (I caught it with the new testcase).
Not sure if this is really required now that kernel is avoid including
linux/mount.h on linux/fs.h.
* Adhemerval Zanella Netto:
>>> diff --git a/sysdeps/unix/sysv/linux/sys/mount.h b/sysdeps/unix/sysv/linux/sys/mount.h
>>> index f965986ba8..ae8406838b 100644
>>> --- a/sysdeps/unix/sysv/linux/sys/mount.h
>>> +++ b/sysdeps/unix/sysv/linux/sys/mount.h
>>> @@ -27,6 +27,19 @@
>>> #include <stddef.h>
>>> #include <sys/ioctl.h>
>>>
>>> +#ifdef __has_include
>>> +# if __has_include ("linux/mount.h")
>>> +# include "linux/mount.h"
>>> +# ifdef FSOPEN_CLOEXEC
>>> +# define __mount_fsopen_cloexec_defined 1
>>> +# endif
>>> +# ifdef MOUNT_ATTR_SIZE_VER0
>>> +# define __mount_attr_size_ver0_defined 1
>>> +# endif
>>> +# endif
>>> +#endif
>>
>> I think those __mount_ defines are not *that* useful.
>
> Not sure I am following, should I remove them? If so it would require
> some more ifdefs on their usage below.
Yes, basically check FSOPEN_CLOEXEC and MOUNT_ATTR_SIZE_VER0 directly.
It's required to get this to work without __has_include, if I'm not
mistkaen.
>>> +
>>> +#undef BLOCK_SIZE
>>> #define BLOCK_SIZE 1024
>>
>> If we don't have enum constants, should we #undef things? If we
>> redefine as the same token as the kernel, there won't be a preprocessor
>> warning.
>
> This is required because of linux/fs.h (I caught it with the new testcase).
> Not sure if this is really required now that kernel is avoid including
> linux/mount.h on linux/fs.h.
Ah. BLOCK_SIZE is special:
#define BLOCK_SIZE_BITS 10
#define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
So not 1024 and hence warning-prone.
But for the other definitions that use integer literals, we should
probably use the same literal as the kernel in our headers and not
#undef these constants (as an additional consistency check).
Thanks,
Florian
new file mode 100755
@@ -0,0 +1,45 @@
+#!/usr/bin/python3
+# Provide functions to build code snippets.
+# Copyright (C) 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/>.
+
+import os.path
+import subprocess
+import tempfile
+import collections
+
+CompileResult = collections.namedtuple("CompileResult", "returncode output")
+
+def compile_c_snippet(snippet, cc, extra_cc_args=""):
+ """Compile and return whether the SNIPPET can be build with CC along
+ EXTRA_CC_ARGS compiler flags. Return a CompileResult with RETURNCODE
+ being 0 for success, or the failure value and the compiler output.
+ """
+ with tempfile.TemporaryDirectory() as temp_dir:
+ c_file_name = os.path.join(temp_dir, 'test.c')
+ obj_file_name = os.path.join(temp_dir, 'test.o')
+ with open(c_file_name, 'w') as c_file:
+ c_file.write(snippet)
+ # Compilation has to be from stdin to avoid the temporary file
+ # name being written into the generated dependencies.
+ cmd = ('%s %s -c -o %s -x c - < %s' % (cc, extra_cc_args,
+ obj_file_name, c_file_name))
+ try:
+ return CompileResult(subprocess.run(cmd, shell=True,
+ capture_output=True, check=True).returncode, "")
+ except subprocess.SubprocessError as e:
+ return CompileResult(1, e.stderr)
@@ -265,6 +265,14 @@ $(objpfx)tst-mount-consts.out: ../sysdeps/unix/sysv/linux/tst-mount-consts.py
< /dev/null > $@ 2>&1; $(evaluate-test)
$(objpfx)tst-mount-consts.out: $(sysdeps-linux-python-deps)
+tests-special += $(objpfx)tst-mount-compile.ou
+$(objpfx)tst-mount-compile.out: ../sysdeps/unix/sysv/linux/tst-mount-compile.py
+ $(sysdeps-linux-python) \
+ ../sysdeps/unix/sysv/linux/tst-mount-compile.py \
+ $(sysdeps-linux-python-cc) \
+ < /dev/null > $@ 2>&1; $(evaluate-test)
+$(objpfx)tst-mount-compile.out: $(sysdeps-linux-python-deps)
+
tst-rseq-disable-ENV = GLIBC_TUNABLES=glibc.pthread.rseq=0
endif # $(subdir) == misc
@@ -27,6 +27,19 @@
#include <stddef.h>
#include <sys/ioctl.h>
+#ifdef __has_include
+# if __has_include ("linux/mount.h")
+# include "linux/mount.h"
+# ifdef FSOPEN_CLOEXEC
+# define __mount_fsopen_cloexec_defined 1
+# endif
+# ifdef MOUNT_ATTR_SIZE_VER0
+# define __mount_attr_size_ver0_defined 1
+# endif
+# endif
+#endif
+
+#undef BLOCK_SIZE
#define BLOCK_SIZE 1024
#define BLOCK_SIZE_BITS 10
@@ -35,70 +48,100 @@
supported */
enum
{
+#undef MS_RDONLY
MS_RDONLY = 1, /* Mount read-only. */
#define MS_RDONLY MS_RDONLY
+#undef MS_NOSUID
MS_NOSUID = 2, /* Ignore suid and sgid bits. */
#define MS_NOSUID MS_NOSUID
+#undef MS_NODEV
MS_NODEV = 4, /* Disallow access to device special files. */
#define MS_NODEV MS_NODEV
+#undef MS_NOEXEC
MS_NOEXEC = 8, /* Disallow program execution. */
#define MS_NOEXEC MS_NOEXEC
+#undef MS_SYNCHRONOUS
MS_SYNCHRONOUS = 16, /* Writes are synced at once. */
#define MS_SYNCHRONOUS MS_SYNCHRONOUS
+#undef MS_REMOUNT
MS_REMOUNT = 32, /* Alter flags of a mounted FS. */
#define MS_REMOUNT MS_REMOUNT
+#undef MS_MANDLOCK
MS_MANDLOCK = 64, /* Allow mandatory locks on an FS. */
#define MS_MANDLOCK MS_MANDLOCK
+#undef MS_DIRSYNC
MS_DIRSYNC = 128, /* Directory modifications are synchronous. */
#define MS_DIRSYNC MS_DIRSYNC
+#undef MS_NOSYMFOLLOW
MS_NOSYMFOLLOW = 256, /* Do not follow symlinks. */
#define MS_NOSYMFOLLOW MS_NOSYMFOLLOW
+#undef MS_NOATIME
MS_NOATIME = 1024, /* Do not update access times. */
#define MS_NOATIME MS_NOATIME
+#undef MS_NODIRATIME
MS_NODIRATIME = 2048, /* Do not update directory access times. */
#define MS_NODIRATIME MS_NODIRATIME
+#undef MS_BIND
MS_BIND = 4096, /* Bind directory at different place. */
#define MS_BIND MS_BIND
+#undef MS_MOVE
MS_MOVE = 8192,
#define MS_MOVE MS_MOVE
+#undef MS_REC
MS_REC = 16384,
#define MS_REC MS_REC
+#undef MS_SILENT
MS_SILENT = 32768,
#define MS_SILENT MS_SILENT
+#undef MS_POSIXACL
MS_POSIXACL = 1 << 16, /* VFS does not apply the umask. */
#define MS_POSIXACL MS_POSIXACL
+#undef MS_UNBINDABLE
MS_UNBINDABLE = 1 << 17, /* Change to unbindable. */
#define MS_UNBINDABLE MS_UNBINDABLE
+#undef MS_PRIVATE
MS_PRIVATE = 1 << 18, /* Change to private. */
#define MS_PRIVATE MS_PRIVATE
+#undef MS_SLAVE
MS_SLAVE = 1 << 19, /* Change to slave. */
#define MS_SLAVE MS_SLAVE
+#undef MS_SHARED
MS_SHARED = 1 << 20, /* Change to shared. */
#define MS_SHARED MS_SHARED
+#undef MS_RELATIME
MS_RELATIME = 1 << 21, /* Update atime relative to mtime/ctime. */
#define MS_RELATIME MS_RELATIME
+#undef MS_KERNMOUNT
MS_KERNMOUNT = 1 << 22, /* This is a kern_mount call. */
#define MS_KERNMOUNT MS_KERNMOUNT
+#undef MS_I_VERSION
MS_I_VERSION = 1 << 23, /* Update inode I_version field. */
#define MS_I_VERSION MS_I_VERSION
+#undef MS_STRICTATIME
MS_STRICTATIME = 1 << 24, /* Always perform atime updates. */
#define MS_STRICTATIME MS_STRICTATIME
+#undef MS_LAZYTIME
MS_LAZYTIME = 1 << 25, /* Update the on-disk [acm]times lazily. */
#define MS_LAZYTIME MS_LAZYTIME
+#undef MS_ACTIVE
MS_ACTIVE = 1 << 30,
#define MS_ACTIVE MS_ACTIVE
+#undef MS_NOUSER
MS_NOUSER = 1 << 31
#define MS_NOUSER MS_NOUSER
};
/* Flags that can be altered by MS_REMOUNT */
+#undef MS_RMT_MASK
#define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION \
|MS_LAZYTIME)
/* Magic mount flag number. Has to be or-ed to the flag values. */
+#undef MS_MGC_VAL
#define MS_MGC_VAL 0xc0ed0000 /* Magic flag number to indicate "new" flags */
+#undef MS_MGC_MSK
#define MS_MGC_MSK 0xffff0000 /* Magic flag number mask */
@@ -106,20 +149,35 @@ enum
is probably as bad and I don't want to create yet another include
file. */
+#undef BLKROSET
#define BLKROSET _IO(0x12, 93) /* Set device read-only (0 = read-write). */
+#undef BLKROGET
#define BLKROGET _IO(0x12, 94) /* Get read-only status (0 = read_write). */
+#undef BLKRRPART
#define BLKRRPART _IO(0x12, 95) /* Re-read partition table. */
+#undef BLKGETSIZE
#define BLKGETSIZE _IO(0x12, 96) /* Return device size. */
+#undef BLKFLSBUF
#define BLKFLSBUF _IO(0x12, 97) /* Flush buffer cache. */
+#undef BLKRASET
#define BLKRASET _IO(0x12, 98) /* Set read ahead for block device. */
+#undef BLKRAGET
#define BLKRAGET _IO(0x12, 99) /* Get current read ahead setting. */
+#undef BLKFRASET
#define BLKFRASET _IO(0x12,100) /* Set filesystem read-ahead. */
+#undef BLKFRAGET
#define BLKFRAGET _IO(0x12,101) /* Get filesystem read-ahead. */
+#undef BLKSECTSET
#define BLKSECTSET _IO(0x12,102) /* Set max sectors per request. */
+#undef BLKSECTGET
#define BLKSECTGET _IO(0x12,103) /* Get max sectors per request. */
+#undef BLKSSZGET
#define BLKSSZGET _IO(0x12,104) /* Get block device sector size. */
+#undef BLKBSZGET
#define BLKBSZGET _IOR(0x12,112,size_t)
+#undef BLKBSZSET
#define BLKBSZSET _IOW(0x12,113,size_t)
+#undef BLKGETSIZE64
#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size. */
@@ -157,6 +215,7 @@ enum
#define MOUNT_ATTR_NOSYMFOLLOW 0x00200000 /* Do not follow symlinks. */
+#ifndef __mount_attr_size_ver0_defined
/* For mount_setattr. */
struct mount_attr
{
@@ -165,6 +224,7 @@ struct mount_attr
uint64_t propagation;
uint64_t userns_fd;
};
+#endif
#define MOUNT_ATTR_SIZE_VER0 32 /* sizeof first published struct */
@@ -185,26 +245,28 @@ struct mount_attr
#define FSPICK_EMPTY_PATH 0x00000008
+#ifndef __mount_fsopen_cloexec_defined
/* The type of fsconfig call made. */
enum fsconfig_command
{
FSCONFIG_SET_FLAG = 0, /* Set parameter, supplying no value */
-#define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG
+# define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG
FSCONFIG_SET_STRING = 1, /* Set parameter, supplying a string value */
-#define FSCONFIG_SET_STRING FSCONFIG_SET_STRING
+# define FSCONFIG_SET_STRING FSCONFIG_SET_STRING
FSCONFIG_SET_BINARY = 2, /* Set parameter, supplying a binary blob value */
-#define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY
+# define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY
FSCONFIG_SET_PATH = 3, /* Set parameter, supplying an object by path */
-#define FSCONFIG_SET_PATH FSCONFIG_SET_PATH
+# define FSCONFIG_SET_PATH FSCONFIG_SET_PATH
FSCONFIG_SET_PATH_EMPTY = 4, /* Set parameter, supplying an object by (empty) path */
-#define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY
+# define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY
FSCONFIG_SET_FD = 5, /* Set parameter, supplying an object by fd */
-#define FSCONFIG_SET_FD FSCONFIG_SET_FD
+# define FSCONFIG_SET_FD FSCONFIG_SET_FD
FSCONFIG_CMD_CREATE = 6, /* Invoke superblock creation */
-#define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE
+# define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE
FSCONFIG_CMD_RECONFIGURE = 7, /* Invoke superblock reconfiguration */
-#define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE
+# define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE
};
+#endif
/* open_tree flags. */
#define OPEN_TREE_CLONE 1 /* Clone the target tree and attach the clone */
new file mode 100755
@@ -0,0 +1,66 @@
+#!/usr/bin/python3
+# Check if glibc provided sys/mount.h can be used along related kernel
+# headers.
+# Copyright (C) 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/>.
+
+import argparse
+import sys
+
+import glibccompile
+import glibcsyscalls
+
+
+def main():
+ """The main entry point."""
+ parser = argparse.ArgumentParser(
+ description="Check if glibc provided sys/mount.h can be "
+ " used along related kernel headers.")
+ parser.add_argument('--cc', metavar='CC',
+ help='C compiler (including options) to use')
+ args = parser.parse_args()
+
+ linux_version_headers = glibcsyscalls.linux_kernel_version(args.cc)
+ # Linux started to provide mount.h with 5.0.
+ if linux_version_headers < (5, 0):
+ sys.exit (77)
+
+ def check(testname, snippet):
+ # Add -Werror to catch macro redefinitions and _ISOMAC to avoid internal
+ # glibc definitions.
+ r = glibccompile.compile_c_snippet(snippet, args.cc, '-Werror -D_ISOMAC')
+ if r.returncode != 0:
+ print("error: test {}:\n{}".format(testname, r.output.decode()))
+ return r.returncode
+
+ status = max(
+ check("sys/mount.h + linux/mount.h",
+ "#include <sys/mount.h>\n"
+ "#include <linux/mount.h>"),
+ check("sys/mount.h + linux/fs.h",
+ "#include <sys/mount.h>\n"
+ "#include <linux/fs.h>"),
+ check("linux/mount.h + sys/mount.h",
+ "#include <linux/mount.h>\n"
+ "#include <sys/mount.h>"),
+ check("linux/fs.h + sys/mount.h",
+ "#include <linux/fs.h>\n"
+ "#include <sys/mount.h>"))
+ sys.exit(status)
+
+if __name__ == '__main__':
+ main()