Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'fs.mount_setattr.v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull mount_setattr test/doc fixes from Christian Brauner:
"This contains a fix for one of the selftests for the mount_setattr
syscall to create idmapped mounts, an entry for idmapped mounts for
maintainers, and missing kernel documentation for the helper we split
out some time ago to get and yield write access to a mount when
changing mount properties"
* tag 'fs.mount_setattr.v5.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
fs: add kernel doc for mnt_{hold,unhold}_writers()
MAINTAINERS: add entry for idmapped mounts
tests: fix idmapped mount_setattr test
+41
-2
+9
MAINTAINERS
+9
MAINTAINERS
···
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W: https://github.com/o2genum/ideapad-slidebar
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F: drivers/input/misc/ideapad_slidebar.c
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+
IDMAPPED MOUNTS
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M: Christian Brauner <brauner@kernel.org>
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L: linux-fsdevel@vger.kernel.org
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S: Maintained
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T: git git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux.git
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F: Documentation/filesystems/idmappings.rst
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F: tools/testing/selftests/mount_setattr/
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F: include/linux/mnt_idmapping.h
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+
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IDT VersaClock 5 CLOCK DRIVER
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M: Luca Ceresoli <luca@lucaceresoli.net>
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S: Maintained
+30
fs/namespace.c
+30
fs/namespace.c
···
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}
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EXPORT_SYMBOL(mnt_drop_write_file);
471
471
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+
/**
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+
* mnt_hold_writers - prevent write access to the given mount
474
+
* @mnt: mnt to prevent write access to
475
+
*
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* Prevents write access to @mnt if there are no active writers for @mnt.
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+
* This function needs to be called and return successfully before changing
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+
* properties of @mnt that need to remain stable for callers with write access
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+
* to @mnt.
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+
*
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+
* After this functions has been called successfully callers must pair it with
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+
* a call to mnt_unhold_writers() in order to stop preventing write access to
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+
* @mnt.
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+
*
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+
* Context: This function expects lock_mount_hash() to be held serializing
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* setting MNT_WRITE_HOLD.
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* Return: On success 0 is returned.
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+
* On error, -EBUSY is returned.
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+
*/
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static inline int mnt_hold_writers(struct mount *mnt)
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{
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mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
···
518
500
return 0;
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}
520
502
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+
/**
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+
* mnt_unhold_writers - stop preventing write access to the given mount
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+
* @mnt: mnt to stop preventing write access to
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+
*
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+
* Stop preventing write access to @mnt allowing callers to gain write access
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+
* to @mnt again.
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+
*
510
+
* This function can only be called after a successful call to
511
+
* mnt_hold_writers().
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+
*
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* Context: This function expects lock_mount_hash() to be held.
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+
*/
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static inline void mnt_unhold_writers(struct mount *mnt)
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{
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/*
+2
-2
tools/testing/selftests/mount_setattr/mount_setattr_test.c
+2
-2
tools/testing/selftests/mount_setattr/mount_setattr_test.c
···
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}
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/**
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-
* Validate that an attached mount in our mount namespace can be idmapped.
1239
+
* Validate that an attached mount in our mount namespace cannot be idmapped.
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* (The kernel enforces that the mount's mount namespace and the caller's mount
1241
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* namespace match.)
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*/
···
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attr.userns_fd = get_userns_fd(0, 10000, 10000);
1261
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ASSERT_GE(attr.userns_fd, 0);
1262
-
ASSERT_EQ(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
1262
+
ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
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ASSERT_EQ(close(attr.userns_fd), 0);
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ASSERT_EQ(close(open_tree_fd), 0);
1265
1265
}