coccinelle: alloc_cast: drop removed allocatorsgrafted

- pci_alloc_consistent() and pci_zalloc_consistent() were removed by
  commit 7968778914e5
  ("PCI: Remove the deprecated "pci-dma-compat.h" API")

- kmem_alloc() was removed by commit f078d4ea8276
  ("xfs: convert kmem_alloc() to kmalloc()")

- kmem_zalloc() was removed by commit 10634530f7ba
  ("xfs: convert kmem_zalloc() to kzalloc()")

- kmem_zone_alloc() and kmem_zone_zalloc() were removed by commit
  bae633a4a283 ("xfs: remove xfs_zone_{alloc,zalloc} helpers")

So drop them from the rules.

No functional change.

Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>

1 files changed, 932 insertions, 0 deletions

diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
new file mode 100644
index 000000000..e054e6291
--- /dev/null
+++ b/fs/debugfs/inode.c
@@ -0,0 +1,932 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  inode.c - part of debugfs, a tiny little debug file system
+ *
+ *  Copyright (C) 2004,2019 Greg Kroah-Hartman <greg@kroah.com>
+ *  Copyright (C) 2004 IBM Inc.
+ *  Copyright (C) 2019 Linux Foundation <gregkh@linuxfoundation.org>
+ *
+ *  debugfs is for people to use instead of /proc or /sys.
+ *  See ./Documentation/core-api/kernel-api.rst for more details.
+ */
+
+#define pr_fmt(fmt)	"debugfs: " fmt
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
+#include <linux/pagemap.h>
+#include <linux/init.h>
+#include <linux/kobject.h>
+#include <linux/namei.h>
+#include <linux/debugfs.h>
+#include <linux/fsnotify.h>
+#include <linux/string.h>
+#include <linux/seq_file.h>
+#include <linux/magic.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+
+#include "internal.h"
+
+#define DEBUGFS_DEFAULT_MODE	0700
+
+static struct vfsmount *debugfs_mount;
+static int debugfs_mount_count;
+static bool debugfs_registered;
+static bool debugfs_enabled __ro_after_init = IS_ENABLED(CONFIG_DEBUG_FS_ALLOW_ALL);
+
+/*
+ * Don't allow access attributes to be changed whilst the kernel is locked down
+ * so that we can use the file mode as part of a heuristic to determine whether
+ * to lock down individual files.
+ */
+static int debugfs_setattr(struct mnt_idmap *idmap,
+			   struct dentry *dentry, struct iattr *ia)
+{
+	int ret;
+
+	if (ia->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) {
+		ret = security_locked_down(LOCKDOWN_DEBUGFS);
+		if (ret)
+			return ret;
+	}
+	return simple_setattr(&nop_mnt_idmap, dentry, ia);
+}
+
+static const struct inode_operations debugfs_file_inode_operations = {
+	.setattr	= debugfs_setattr,
+};
+static const struct inode_operations debugfs_dir_inode_operations = {
+	.lookup		= simple_lookup,
+	.setattr	= debugfs_setattr,
+};
+static const struct inode_operations debugfs_symlink_inode_operations = {
+	.get_link	= simple_get_link,
+	.setattr	= debugfs_setattr,
+};
+
+static struct inode *debugfs_get_inode(struct super_block *sb)
+{
+	struct inode *inode = new_inode(sb);
+	if (inode) {
+		inode->i_ino = get_next_ino();
+		simple_inode_init_ts(inode);
+	}
+	return inode;
+}
+
+struct debugfs_fs_info {
+	kuid_t uid;
+	kgid_t gid;
+	umode_t mode;
+	/* Opt_* bitfield. */
+	unsigned int opts;
+};
+
+enum {
+	Opt_uid,
+	Opt_gid,
+	Opt_mode,
+	Opt_source,
+};
+
+static const struct fs_parameter_spec debugfs_param_specs[] = {
+	fsparam_gid	("gid",		Opt_gid),
+	fsparam_u32oct	("mode",	Opt_mode),
+	fsparam_uid	("uid",		Opt_uid),
+	fsparam_string	("source",	Opt_source),
+	{}
+};
+
+static int debugfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+	struct debugfs_fs_info *opts = fc->s_fs_info;
+	struct fs_parse_result result;
+	int opt;
+
+	opt = fs_parse(fc, debugfs_param_specs, param, &result);
+	if (opt < 0) {
+		/*
+                * We might like to report bad mount options here; but
+                * traditionally debugfs has ignored all mount options
+                */
+		if (opt == -ENOPARAM)
+			return 0;
+
+		return opt;
+	}
+
+	switch (opt) {
+	case Opt_uid:
+		opts->uid = result.uid;
+		break;
+	case Opt_gid:
+		opts->gid = result.gid;
+		break;
+	case Opt_mode:
+		opts->mode = result.uint_32 & S_IALLUGO;
+		break;
+	case Opt_source:
+		if (fc->source)
+			return invalfc(fc, "Multiple sources specified");
+		fc->source = param->string;
+		param->string = NULL;
+		break;
+	/*
+	 * We might like to report bad mount options here;
+	 * but traditionally debugfs has ignored all mount options
+	 */
+	}
+
+	opts->opts |= BIT(opt);
+
+	return 0;
+}
+
+static void _debugfs_apply_options(struct super_block *sb, bool remount)
+{
+	struct debugfs_fs_info *fsi = sb->s_fs_info;
+	struct inode *inode = d_inode(sb->s_root);
+
+	/*
+	 * On remount, only reset mode/uid/gid if they were provided as mount
+	 * options.
+	 */
+
+	if (!remount || fsi->opts & BIT(Opt_mode)) {
+		inode->i_mode &= ~S_IALLUGO;
+		inode->i_mode |= fsi->mode;
+	}
+
+	if (!remount || fsi->opts & BIT(Opt_uid))
+		inode->i_uid = fsi->uid;
+
+	if (!remount || fsi->opts & BIT(Opt_gid))
+		inode->i_gid = fsi->gid;
+}
+
+static void debugfs_apply_options(struct super_block *sb)
+{
+	_debugfs_apply_options(sb, false);
+}
+
+static void debugfs_apply_options_remount(struct super_block *sb)
+{
+	_debugfs_apply_options(sb, true);
+}
+
+static int debugfs_reconfigure(struct fs_context *fc)
+{
+	struct super_block *sb = fc->root->d_sb;
+	struct debugfs_fs_info *sb_opts = sb->s_fs_info;
+	struct debugfs_fs_info *new_opts = fc->s_fs_info;
+
+	if (!new_opts)
+		return 0;
+
+	sync_filesystem(sb);
+
+	/* structure copy of new mount options to sb */
+	*sb_opts = *new_opts;
+	debugfs_apply_options_remount(sb);
+
+	return 0;
+}
+
+static int debugfs_show_options(struct seq_file *m, struct dentry *root)
+{
+	struct debugfs_fs_info *fsi = root->d_sb->s_fs_info;
+
+	if (!uid_eq(fsi->uid, GLOBAL_ROOT_UID))
+		seq_printf(m, ",uid=%u",
+			   from_kuid_munged(&init_user_ns, fsi->uid));
+	if (!gid_eq(fsi->gid, GLOBAL_ROOT_GID))
+		seq_printf(m, ",gid=%u",
+			   from_kgid_munged(&init_user_ns, fsi->gid));
+	if (fsi->mode != DEBUGFS_DEFAULT_MODE)
+		seq_printf(m, ",mode=%o", fsi->mode);
+
+	return 0;
+}
+
+static struct kmem_cache *debugfs_inode_cachep __ro_after_init;
+
+static void init_once(void *foo)
+{
+	struct debugfs_inode_info *info = foo;
+	inode_init_once(&info->vfs_inode);
+}
+
+static struct inode *debugfs_alloc_inode(struct super_block *sb)
+{
+	struct debugfs_inode_info *info;
+	info = alloc_inode_sb(sb, debugfs_inode_cachep, GFP_KERNEL);
+	if (!info)
+		return NULL;
+	return &info->vfs_inode;
+}
+
+static void debugfs_free_inode(struct inode *inode)
+{
+	if (S_ISLNK(inode->i_mode))
+		kfree(inode->i_link);
+	kmem_cache_free(debugfs_inode_cachep, DEBUGFS_I(inode));
+}
+
+static const struct super_operations debugfs_super_operations = {
+	.statfs		= simple_statfs,
+	.show_options	= debugfs_show_options,
+	.alloc_inode	= debugfs_alloc_inode,
+	.free_inode	= debugfs_free_inode,
+};
+
+static void debugfs_release_dentry(struct dentry *dentry)
+{
+	struct debugfs_fsdata *fsd = dentry->d_fsdata;
+
+	if (fsd) {
+		WARN_ON(!list_empty(&fsd->cancellations));
+		mutex_destroy(&fsd->cancellations_mtx);
+	}
+	kfree(fsd);
+}
+
+static struct vfsmount *debugfs_automount(struct path *path)
+{
+	struct inode *inode = path->dentry->d_inode;
+
+	return DEBUGFS_I(inode)->automount(path->dentry, inode->i_private);
+}
+
+static const struct dentry_operations debugfs_dops = {
+	.d_release = debugfs_release_dentry,
+	.d_automount = debugfs_automount,
+};
+
+static int debugfs_fill_super(struct super_block *sb, struct fs_context *fc)
+{
+	static const struct tree_descr debug_files[] = {{""}};
+	int err;
+
+	err = simple_fill_super(sb, DEBUGFS_MAGIC, debug_files);
+	if (err)
+		return err;
+
+	sb->s_op = &debugfs_super_operations;
+	set_default_d_op(sb, &debugfs_dops);
+	sb->s_d_flags |= DCACHE_DONTCACHE;
+
+	debugfs_apply_options(sb);
+
+	return 0;
+}
+
+static int debugfs_get_tree(struct fs_context *fc)
+{
+	int err;
+
+	err = get_tree_single(fc, debugfs_fill_super);
+	if (err)
+		return err;
+
+	return debugfs_reconfigure(fc);
+}
+
+static void debugfs_free_fc(struct fs_context *fc)
+{
+	kfree(fc->s_fs_info);
+}
+
+static const struct fs_context_operations debugfs_context_ops = {
+	.free		= debugfs_free_fc,
+	.parse_param	= debugfs_parse_param,
+	.get_tree	= debugfs_get_tree,
+	.reconfigure	= debugfs_reconfigure,
+};
+
+static int debugfs_init_fs_context(struct fs_context *fc)
+{
+	struct debugfs_fs_info *fsi;
+
+	fsi = kzalloc_obj(struct debugfs_fs_info);
+	if (!fsi)
+		return -ENOMEM;
+
+	fsi->mode = DEBUGFS_DEFAULT_MODE;
+
+	fc->s_fs_info = fsi;
+	fc->ops = &debugfs_context_ops;
+	return 0;
+}
+
+static struct file_system_type debug_fs_type = {
+	.owner =	THIS_MODULE,
+	.name =		"debugfs",
+	.init_fs_context = debugfs_init_fs_context,
+	.parameters =	debugfs_param_specs,
+	.kill_sb =	kill_anon_super,
+};
+MODULE_ALIAS_FS("debugfs");
+
+/**
+ * debugfs_lookup() - look up an existing debugfs file
+ * @name: a pointer to a string containing the name of the file to look up.
+ * @parent: a pointer to the parent dentry of the file.
+ *
+ * This function will return a pointer to a dentry if it succeeds.  If the file
+ * doesn't exist or an error occurs, %NULL will be returned.  The returned
+ * dentry must be passed to dput() when it is no longer needed.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned.
+ */
+struct dentry *debugfs_lookup(const char *name, struct dentry *parent)
+{
+	struct dentry *dentry;
+
+	if (!debugfs_initialized() || IS_ERR_OR_NULL(name) || IS_ERR(parent))
+		return NULL;
+
+	if (!parent)
+		parent = debugfs_mount->mnt_root;
+
+	dentry = lookup_noperm_positive_unlocked(&QSTR(name), parent);
+	if (IS_ERR(dentry))
+		return NULL;
+	return dentry;
+}
+EXPORT_SYMBOL_GPL(debugfs_lookup);
+
+static struct dentry *debugfs_start_creating(const char *name,
+					     struct dentry *parent)
+{
+	struct dentry *dentry;
+	int error;
+
+	if (!debugfs_enabled)
+		return ERR_PTR(-EPERM);
+
+	if (!debugfs_initialized()) {
+		pr_err("Unable to create file '%s', debugfs is not initialized yet\n",
+		       name);
+		return ERR_PTR(-ENOENT);
+	}
+
+	pr_debug("creating file '%s'\n", name);
+
+	if (IS_ERR(parent))
+		return parent;
+
+	error = simple_pin_fs(&debug_fs_type, &debugfs_mount,
+			      &debugfs_mount_count);
+	if (error) {
+		pr_err("Unable to pin filesystem for file '%s'\n", name);
+		return ERR_PTR(error);
+	}
+
+	/* If the parent is not specified, we create it in the root.
+	 * We need the root dentry to do this, which is in the super
+	 * block. A pointer to that is in the struct vfsmount that we
+	 * have around.
+	 */
+	if (!parent)
+		parent = debugfs_mount->mnt_root;
+
+	dentry = simple_start_creating(parent, name);
+	if (IS_ERR(dentry)) {
+		if (dentry == ERR_PTR(-EEXIST))
+			pr_err("'%s' already exists in '%pd'\n", name, parent);
+		simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+	}
+	return dentry;
+}
+
+static struct dentry *debugfs_failed_creating(struct dentry *dentry)
+{
+	simple_done_creating(dentry);
+	simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+	return ERR_PTR(-ENOMEM);
+}
+
+static struct dentry *debugfs_end_creating(struct dentry *dentry)
+{
+	simple_done_creating(dentry);
+	return dentry; // borrowed
+}
+
+static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
+				struct dentry *parent, void *data,
+				const void *aux,
+				const struct file_operations *proxy_fops,
+				const void *real_fops)
+{
+	struct dentry *dentry;
+	struct inode *inode;
+
+	if (!(mode & S_IFMT))
+		mode |= S_IFREG;
+	BUG_ON(!S_ISREG(mode));
+	dentry = debugfs_start_creating(name, parent);
+
+	if (IS_ERR(dentry))
+		return dentry;
+
+	inode = debugfs_get_inode(dentry->d_sb);
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create file '%s'\n",
+		       name);
+		return debugfs_failed_creating(dentry);
+	}
+
+	inode->i_mode = mode;
+	inode->i_private = data;
+
+	inode->i_op = &debugfs_file_inode_operations;
+	if (!real_fops)
+		proxy_fops = &debugfs_noop_file_operations;
+	inode->i_fop = proxy_fops;
+	DEBUGFS_I(inode)->raw = real_fops;
+	DEBUGFS_I(inode)->aux = (void *)aux;
+
+	d_make_persistent(dentry, inode);
+	fsnotify_create(d_inode(dentry->d_parent), dentry);
+	return debugfs_end_creating(dentry);
+}
+
+struct dentry *debugfs_create_file_full(const char *name, umode_t mode,
+					struct dentry *parent, void *data,
+					const void *aux,
+					const struct file_operations *fops)
+{
+	return __debugfs_create_file(name, mode, parent, data, aux,
+				&debugfs_full_proxy_file_operations,
+				fops);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_file_full);
+
+struct dentry *debugfs_create_file_short(const char *name, umode_t mode,
+					struct dentry *parent, void *data,
+					const void *aux,
+					const struct debugfs_short_fops *fops)
+{
+	return __debugfs_create_file(name, mode, parent, data, aux,
+				&debugfs_full_short_proxy_file_operations,
+				fops);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_file_short);
+
+/**
+ * debugfs_create_file_unsafe - create a file in the debugfs filesystem
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have.
+ * @parent: a pointer to the parent dentry for this file.  This should be a
+ *          directory dentry if set.  If this parameter is NULL, then the
+ *          file will be created in the root of the debugfs filesystem.
+ * @data: a pointer to something that the caller will want to get to later
+ *        on.  The inode.i_private pointer will point to this value on
+ *        the open() call.
+ * @fops: a pointer to a struct file_operations that should be used for
+ *        this file.
+ *
+ * debugfs_create_file_unsafe() is completely analogous to
+ * debugfs_create_file(), the only difference being that the fops
+ * handed it will not get protected against file removals by the
+ * debugfs core.
+ *
+ * It is your responsibility to protect your struct file_operation
+ * methods against file removals by means of debugfs_file_get()
+ * and debugfs_file_put(). ->open() is still protected by
+ * debugfs though.
+ *
+ * Any struct file_operations defined by means of
+ * DEFINE_DEBUGFS_ATTRIBUTE() is protected against file removals and
+ * thus, may be used here.
+ */
+struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
+				   struct dentry *parent, void *data,
+				   const struct file_operations *fops)
+{
+
+	return __debugfs_create_file(name, mode, parent, data, NULL,
+				&debugfs_open_proxy_file_operations,
+				fops);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_file_unsafe);
+
+/**
+ * debugfs_create_file_size - create a file in the debugfs filesystem
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have.
+ * @parent: a pointer to the parent dentry for this file.  This should be a
+ *          directory dentry if set.  If this parameter is NULL, then the
+ *          file will be created in the root of the debugfs filesystem.
+ * @data: a pointer to something that the caller will want to get to later
+ *        on.  The inode.i_private pointer will point to this value on
+ *        the open() call.
+ * @fops: a pointer to a struct file_operations that should be used for
+ *        this file.
+ * @file_size: initial file size
+ *
+ * This is the basic "create a file" function for debugfs.  It allows for a
+ * wide range of flexibility in creating a file, or a directory (if you want
+ * to create a directory, the debugfs_create_dir() function is
+ * recommended to be used instead.)
+ */
+void debugfs_create_file_size(const char *name, umode_t mode,
+			      struct dentry *parent, void *data,
+			      const struct file_operations *fops,
+			      loff_t file_size)
+{
+	struct dentry *de = debugfs_create_file(name, mode, parent, data, fops);
+
+	if (!IS_ERR(de))
+		d_inode(de)->i_size = file_size;
+}
+EXPORT_SYMBOL_GPL(debugfs_create_file_size);
+
+/**
+ * debugfs_create_dir - create a directory in the debugfs filesystem
+ * @name: a pointer to a string containing the name of the directory to
+ *        create.
+ * @parent: a pointer to the parent dentry for this file.  This should be a
+ *          directory dentry if set.  If this parameter is NULL, then the
+ *          directory will be created in the root of the debugfs filesystem.
+ *
+ * This function creates a directory in debugfs with the given name.
+ *
+ * This function will return a pointer to a dentry if it succeeds.  This
+ * pointer must be passed to the debugfs_remove() function when the file is
+ * to be removed (no automatic cleanup happens if your module is unloaded,
+ * you are responsible here.)  If an error occurs, ERR_PTR(-ERROR) will be
+ * returned.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned.
+ *
+ * NOTE: it's expected that most callers should _ignore_ the errors returned
+ * by this function. Other debugfs functions handle the fact that the "dentry"
+ * passed to them could be an error and they don't crash in that case.
+ * Drivers should generally work fine even if debugfs fails to init anyway.
+ */
+struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
+{
+	struct dentry *dentry = debugfs_start_creating(name, parent);
+	struct inode *inode;
+
+	if (IS_ERR(dentry))
+		return dentry;
+
+	inode = debugfs_get_inode(dentry->d_sb);
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create directory '%s'\n",
+		       name);
+		return debugfs_failed_creating(dentry);
+	}
+
+	inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
+	inode->i_op = &debugfs_dir_inode_operations;
+	inode->i_fop = &simple_dir_operations;
+
+	/* directory inodes start off with i_nlink == 2 (for "." entry) */
+	inc_nlink(inode);
+	d_make_persistent(dentry, inode);
+	inc_nlink(d_inode(dentry->d_parent));
+	fsnotify_mkdir(d_inode(dentry->d_parent), dentry);
+	return debugfs_end_creating(dentry);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_dir);
+
+/**
+ * debugfs_create_automount - create automount point in the debugfs filesystem
+ * @name: a pointer to a string containing the name of the file to create.
+ * @parent: a pointer to the parent dentry for this file.  This should be a
+ *          directory dentry if set.  If this parameter is NULL, then the
+ *          file will be created in the root of the debugfs filesystem.
+ * @f: function to be called when pathname resolution steps on that one.
+ * @data: opaque argument to pass to f().
+ *
+ * @f should return what ->d_automount() would.
+ */
+struct dentry *debugfs_create_automount(const char *name,
+					struct dentry *parent,
+					debugfs_automount_t f,
+					void *data)
+{
+	struct dentry *dentry = debugfs_start_creating(name, parent);
+	struct inode *inode;
+
+	if (IS_ERR(dentry))
+		return dentry;
+
+	inode = debugfs_get_inode(dentry->d_sb);
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create automount '%s'\n",
+		       name);
+		return debugfs_failed_creating(dentry);
+	}
+
+	make_empty_dir_inode(inode);
+	inode->i_flags |= S_AUTOMOUNT;
+	inode->i_private = data;
+	DEBUGFS_I(inode)->automount = f;
+	/* directory inodes start off with i_nlink == 2 (for "." entry) */
+	inc_nlink(inode);
+	d_make_persistent(dentry, inode);
+	inc_nlink(d_inode(dentry->d_parent));
+	fsnotify_mkdir(d_inode(dentry->d_parent), dentry);
+	return debugfs_end_creating(dentry);
+}
+EXPORT_SYMBOL(debugfs_create_automount);
+
+/**
+ * debugfs_create_symlink- create a symbolic link in the debugfs filesystem
+ * @name: a pointer to a string containing the name of the symbolic link to
+ *        create.
+ * @parent: a pointer to the parent dentry for this symbolic link.  This
+ *          should be a directory dentry if set.  If this parameter is NULL,
+ *          then the symbolic link will be created in the root of the debugfs
+ *          filesystem.
+ * @target: a pointer to a string containing the path to the target of the
+ *          symbolic link.
+ *
+ * This function creates a symbolic link with the given name in debugfs that
+ * links to the given target path.
+ *
+ * This function will return a pointer to a dentry if it succeeds.  This
+ * pointer must be passed to the debugfs_remove() function when the symbolic
+ * link is to be removed (no automatic cleanup happens if your module is
+ * unloaded, you are responsible here.)  If an error occurs, ERR_PTR(-ERROR)
+ * will be returned.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned.
+ */
+struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
+				      const char *target)
+{
+	struct dentry *dentry;
+	struct inode *inode;
+	char *link = kstrdup(target, GFP_KERNEL);
+	if (!link)
+		return ERR_PTR(-ENOMEM);
+
+	dentry = debugfs_start_creating(name, parent);
+	if (IS_ERR(dentry)) {
+		kfree(link);
+		return dentry;
+	}
+
+	inode = debugfs_get_inode(dentry->d_sb);
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create symlink '%s'\n",
+		       name);
+		kfree(link);
+		return debugfs_failed_creating(dentry);
+	}
+	inode->i_mode = S_IFLNK | S_IRWXUGO;
+	inode->i_op = &debugfs_symlink_inode_operations;
+	inode->i_link = link;
+	d_make_persistent(dentry, inode);
+	return debugfs_end_creating(dentry);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_symlink);
+
+static void __debugfs_file_removed(struct dentry *dentry)
+{
+	struct debugfs_fsdata *fsd;
+
+	/*
+	 * Paired with the closing smp_mb() implied by a successful
+	 * cmpxchg() in debugfs_file_get(): either
+	 * debugfs_file_get() must see a dead dentry or we must see a
+	 * debugfs_fsdata instance at ->d_fsdata here (or both).
+	 */
+	smp_mb();
+	fsd = READ_ONCE(dentry->d_fsdata);
+	if (!fsd)
+		return;
+
+	/* if this was the last reference, we're done */
+	if (refcount_dec_and_test(&fsd->active_users))
+		return;
+
+	/*
+	 * If there's still a reference, the code that obtained it can
+	 * be in different states:
+	 *  - The common case of not using cancellations, or already
+	 *    after debugfs_leave_cancellation(), where we just need
+	 *    to wait for debugfs_file_put() which signals the completion;
+	 *  - inside a cancellation section, i.e. between
+	 *    debugfs_enter_cancellation() and debugfs_leave_cancellation(),
+	 *    in which case we need to trigger the ->cancel() function,
+	 *    and then wait for debugfs_file_put() just like in the
+	 *    previous case;
+	 *  - before debugfs_enter_cancellation() (but obviously after
+	 *    debugfs_file_get()), in which case we may not see the
+	 *    cancellation in the list on the first round of the loop,
+	 *    but debugfs_enter_cancellation() signals the completion
+	 *    after adding it, so this code gets woken up to call the
+	 *    ->cancel() function.
+	 */
+	while (refcount_read(&fsd->active_users)) {
+		struct debugfs_cancellation *c;
+
+		/*
+		 * Lock the cancellations. Note that the cancellations
+		 * structs are meant to be on the stack, so we need to
+		 * ensure we either use them here or don't touch them,
+		 * and debugfs_leave_cancellation() will wait for this
+		 * to be finished processing before exiting one. It may
+		 * of course win and remove the cancellation, but then
+		 * chances are we never even got into this bit, we only
+		 * do if the refcount isn't zero already.
+		 */
+		mutex_lock(&fsd->cancellations_mtx);
+		while ((c = list_first_entry_or_null(&fsd->cancellations,
+						     typeof(*c), list))) {
+			list_del_init(&c->list);
+			c->cancel(dentry, c->cancel_data);
+		}
+		mutex_unlock(&fsd->cancellations_mtx);
+
+		wait_for_completion(&fsd->active_users_drained);
+	}
+}
+
+static void remove_one(struct dentry *victim)
+{
+        if (d_is_reg(victim))
+		__debugfs_file_removed(victim);
+	simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+}
+
+/**
+ * debugfs_remove - recursively removes a directory
+ * @dentry: a pointer to a the dentry of the directory to be removed.  If this
+ *          parameter is NULL or an error value, nothing will be done.
+ *
+ * This function recursively removes a directory tree in debugfs that
+ * was previously created with a call to another debugfs function
+ * (like debugfs_create_file() or variants thereof.)
+ *
+ * This function is required to be called in order for the file to be
+ * removed, no automatic cleanup of files will happen when a module is
+ * removed, you are responsible here.
+ */
+void debugfs_remove(struct dentry *dentry)
+{
+	if (IS_ERR_OR_NULL(dentry))
+		return;
+
+	simple_pin_fs(&debug_fs_type, &debugfs_mount, &debugfs_mount_count);
+	simple_recursive_removal(dentry, remove_one);
+	simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+}
+EXPORT_SYMBOL_GPL(debugfs_remove);
+
+/**
+ * debugfs_lookup_and_remove - lookup a directory or file and recursively remove it
+ * @name: a pointer to a string containing the name of the item to look up.
+ * @parent: a pointer to the parent dentry of the item.
+ *
+ * This is the equlivant of doing something like
+ * debugfs_remove(debugfs_lookup(..)) but with the proper reference counting
+ * handled for the directory being looked up.
+ */
+void debugfs_lookup_and_remove(const char *name, struct dentry *parent)
+{
+	struct dentry *dentry;
+
+	dentry = debugfs_lookup(name, parent);
+	if (!dentry)
+		return;
+
+	debugfs_remove(dentry);
+	dput(dentry);
+}
+EXPORT_SYMBOL_GPL(debugfs_lookup_and_remove);
+
+/**
+ * debugfs_change_name - rename a file/directory in the debugfs filesystem
+ * @dentry: dentry of an object to be renamed.
+ * @fmt: format for new name
+ *
+ * This function renames a file/directory in debugfs.  The target must not
+ * exist for rename to succeed.
+ *
+ * This function will return 0 on success and -E... on failure.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned.
+ */
+int __printf(2, 3) debugfs_change_name(struct dentry *dentry, const char *fmt, ...)
+{
+	int error = 0;
+	const char *new_name;
+	struct name_snapshot old_name;
+	struct dentry *target;
+	struct renamedata rd = {};
+	struct inode *dir;
+	va_list ap;
+
+	if (IS_ERR_OR_NULL(dentry))
+		return 0;
+
+	va_start(ap, fmt);
+	new_name = kvasprintf_const(GFP_KERNEL, fmt, ap);
+	va_end(ap);
+	if (!new_name)
+		return -ENOMEM;
+
+	rd.old_parent = dget_parent(dentry);
+	rd.new_parent = rd.old_parent;
+	rd.flags = RENAME_NOREPLACE;
+	target = lookup_noperm_unlocked(&QSTR(new_name), rd.new_parent);
+	if (IS_ERR(target)) {
+		error = PTR_ERR(target);
+		goto out_free;
+	}
+
+	error = start_renaming_two_dentries(&rd, dentry, target);
+	if (error) {
+		if (error == -EEXIST && target == dentry)
+			/* it isn't an error to rename a thing to itself */
+			error = 0;
+		goto out;
+	}
+
+	dir = d_inode(rd.old_parent);
+	take_dentry_name_snapshot(&old_name, dentry);
+	simple_rename_timestamp(dir, dentry, dir, rd.new_dentry);
+	d_move(dentry, rd.new_dentry);
+	fsnotify_move(dir, dir, &old_name.name, d_is_dir(dentry), NULL, dentry);
+	release_dentry_name_snapshot(&old_name);
+	end_renaming(&rd);
+out:
+	dput(rd.old_parent);
+	dput(target);
+out_free:
+	kfree_const(new_name);
+	return error;
+}
+EXPORT_SYMBOL_GPL(debugfs_change_name);
+
+/**
+ * debugfs_initialized - Tells whether debugfs has been registered
+ */
+bool debugfs_initialized(void)
+{
+	return debugfs_registered;
+}
+EXPORT_SYMBOL_GPL(debugfs_initialized);
+
+static int __init debugfs_kernel(char *str)
+{
+	if (str) {
+		if (!strcmp(str, "on"))
+			debugfs_enabled = true;
+		else if (!strcmp(str, "off"))
+			debugfs_enabled = false;
+		else if (!strcmp(str, "no-mount")) {
+			pr_notice("debugfs=no-mount is a deprecated alias "
+				  "for debugfs=off\n");
+			debugfs_enabled = false;
+		}
+	}
+
+	return 0;
+}
+early_param("debugfs", debugfs_kernel);
+
+static int __init debugfs_init(void)
+{
+	int retval;
+
+	if (!debugfs_enabled)
+		return -EPERM;
+
+	retval = sysfs_create_mount_point(kernel_kobj, "debug");
+	if (retval)
+		return retval;
+
+	debugfs_inode_cachep = kmem_cache_create("debugfs_inode_cache",
+				sizeof(struct debugfs_inode_info), 0,
+				SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
+				init_once);
+	if (debugfs_inode_cachep == NULL) {
+		sysfs_remove_mount_point(kernel_kobj, "debug");
+		return -ENOMEM;
+	}
+
+	retval = register_filesystem(&debug_fs_type);
+	if (retval) { // Really not going to happen
+		sysfs_remove_mount_point(kernel_kobj, "debug");
+		kmem_cache_destroy(debugfs_inode_cachep);
+		return retval;
+	}
+	debugfs_registered = true;
+	return 0;
+}
+core_initcall(debugfs_init);