forked from Minki/linux
78fae52cf4
It isn't needed at all in these files, dynamic debug is the best way to enable this type of thing, if you really want it. As it is, these defines were not doing anything at all. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
80 lines
1.7 KiB
C
80 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* fs/sysfs/symlink.c - operations for initializing and mounting sysfs
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*
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* Copyright (c) 2001-3 Patrick Mochel
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* Copyright (c) 2007 SUSE Linux Products GmbH
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* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
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*
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* Please see Documentation/filesystems/sysfs.txt for more information.
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*/
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#include <linux/fs.h>
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#include <linux/magic.h>
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#include <linux/mount.h>
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#include <linux/init.h>
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#include <linux/user_namespace.h>
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#include "sysfs.h"
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static struct kernfs_root *sysfs_root;
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struct kernfs_node *sysfs_root_kn;
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static struct dentry *sysfs_mount(struct file_system_type *fs_type,
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int flags, const char *dev_name, void *data)
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{
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struct dentry *root;
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void *ns;
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bool new_sb;
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if (!(flags & SB_KERNMOUNT)) {
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if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET))
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return ERR_PTR(-EPERM);
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}
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ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET);
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root = kernfs_mount_ns(fs_type, flags, sysfs_root,
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SYSFS_MAGIC, &new_sb, ns);
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if (IS_ERR(root) || !new_sb)
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kobj_ns_drop(KOBJ_NS_TYPE_NET, ns);
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else if (new_sb)
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root->d_sb->s_iflags |= SB_I_USERNS_VISIBLE;
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return root;
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}
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static void sysfs_kill_sb(struct super_block *sb)
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{
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void *ns = (void *)kernfs_super_ns(sb);
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kernfs_kill_sb(sb);
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kobj_ns_drop(KOBJ_NS_TYPE_NET, ns);
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}
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static struct file_system_type sysfs_fs_type = {
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.name = "sysfs",
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.mount = sysfs_mount,
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.kill_sb = sysfs_kill_sb,
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.fs_flags = FS_USERNS_MOUNT,
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};
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int __init sysfs_init(void)
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{
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int err;
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sysfs_root = kernfs_create_root(NULL, KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK,
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NULL);
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if (IS_ERR(sysfs_root))
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return PTR_ERR(sysfs_root);
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sysfs_root_kn = sysfs_root->kn;
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err = register_filesystem(&sysfs_fs_type);
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if (err) {
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kernfs_destroy_root(sysfs_root);
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return err;
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}
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return 0;
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}
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