v4.19.13 snapshot.
diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
new file mode 100644
index 0000000..3b0ba54
--- /dev/null
+++ b/include/linux/debugfs.h
@@ -0,0 +1,388 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * debugfs.h - a tiny little debug file system
+ *
+ * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 2004 IBM Inc.
+ *
+ * debugfs is for people to use instead of /proc or /sys.
+ * See Documentation/filesystems/ for more details.
+ */
+
+#ifndef _DEBUGFS_H_
+#define _DEBUGFS_H_
+
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+
+#include <linux/types.h>
+#include <linux/compiler.h>
+
+struct device;
+struct file_operations;
+
+struct debugfs_blob_wrapper {
+ void *data;
+ unsigned long size;
+};
+
+struct debugfs_reg32 {
+ char *name;
+ unsigned long offset;
+};
+
+struct debugfs_regset32 {
+ const struct debugfs_reg32 *regs;
+ int nregs;
+ void __iomem *base;
+};
+
+extern struct dentry *arch_debugfs_dir;
+
+#define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
+static int __fops ## _open(struct inode *inode, struct file *file) \
+{ \
+ __simple_attr_check_format(__fmt, 0ull); \
+ return simple_attr_open(inode, file, __get, __set, __fmt); \
+} \
+static const struct file_operations __fops = { \
+ .owner = THIS_MODULE, \
+ .open = __fops ## _open, \
+ .release = simple_attr_release, \
+ .read = debugfs_attr_read, \
+ .write = debugfs_attr_write, \
+ .llseek = no_llseek, \
+}
+
+#if defined(CONFIG_DEBUG_FS)
+
+struct dentry *debugfs_lookup(const char *name, struct dentry *parent);
+
+struct dentry *debugfs_create_file(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops);
+struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops);
+
+struct dentry *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 *debugfs_create_dir(const char *name, struct dentry *parent);
+
+struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
+ const char *dest);
+
+typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
+struct dentry *debugfs_create_automount(const char *name,
+ struct dentry *parent,
+ debugfs_automount_t f,
+ void *data);
+
+void debugfs_remove(struct dentry *dentry);
+void debugfs_remove_recursive(struct dentry *dentry);
+
+const struct file_operations *debugfs_real_fops(const struct file *filp);
+
+int debugfs_file_get(struct dentry *dentry);
+void debugfs_file_put(struct dentry *dentry);
+
+ssize_t debugfs_attr_read(struct file *file, char __user *buf,
+ size_t len, loff_t *ppos);
+ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
+ size_t len, loff_t *ppos);
+
+struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
+ struct dentry *new_dir, const char *new_name);
+
+struct dentry *debugfs_create_u8(const char *name, umode_t mode,
+ struct dentry *parent, u8 *value);
+struct dentry *debugfs_create_u16(const char *name, umode_t mode,
+ struct dentry *parent, u16 *value);
+struct dentry *debugfs_create_u32(const char *name, umode_t mode,
+ struct dentry *parent, u32 *value);
+struct dentry *debugfs_create_u64(const char *name, umode_t mode,
+ struct dentry *parent, u64 *value);
+struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
+ struct dentry *parent, unsigned long *value);
+struct dentry *debugfs_create_x8(const char *name, umode_t mode,
+ struct dentry *parent, u8 *value);
+struct dentry *debugfs_create_x16(const char *name, umode_t mode,
+ struct dentry *parent, u16 *value);
+struct dentry *debugfs_create_x32(const char *name, umode_t mode,
+ struct dentry *parent, u32 *value);
+struct dentry *debugfs_create_x64(const char *name, umode_t mode,
+ struct dentry *parent, u64 *value);
+struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
+ struct dentry *parent, size_t *value);
+struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
+ struct dentry *parent, atomic_t *value);
+struct dentry *debugfs_create_bool(const char *name, umode_t mode,
+ struct dentry *parent, bool *value);
+
+struct dentry *debugfs_create_blob(const char *name, umode_t mode,
+ struct dentry *parent,
+ struct debugfs_blob_wrapper *blob);
+
+struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
+ struct dentry *parent,
+ struct debugfs_regset32 *regset);
+
+void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+ int nregs, void __iomem *base, char *prefix);
+
+struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
+ struct dentry *parent,
+ u32 *array, u32 elements);
+
+struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
+ struct dentry *parent,
+ int (*read_fn)(struct seq_file *s,
+ void *data));
+
+bool debugfs_initialized(void);
+
+ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos);
+
+ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
+ size_t count, loff_t *ppos);
+
+#else
+
+#include <linux/err.h>
+
+/*
+ * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
+ * so users have a chance to detect if there was a real error or not. We don't
+ * want to duplicate the design decision mistakes of procfs and devfs again.
+ */
+
+static inline struct dentry *debugfs_lookup(const char *name,
+ struct dentry *parent)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_file_unsafe(const char *name,
+ umode_t mode, struct dentry *parent,
+ void *data,
+ const struct file_operations *fops)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops,
+ loff_t file_size)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_dir(const char *name,
+ struct dentry *parent)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_symlink(const char *name,
+ struct dentry *parent,
+ const char *dest)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_automount(const char *name,
+ struct dentry *parent,
+ struct vfsmount *(*f)(void *),
+ void *data)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline void debugfs_remove(struct dentry *dentry)
+{ }
+
+static inline void debugfs_remove_recursive(struct dentry *dentry)
+{ }
+
+const struct file_operations *debugfs_real_fops(const struct file *filp);
+
+static inline int debugfs_file_get(struct dentry *dentry)
+{
+ return 0;
+}
+
+static inline void debugfs_file_put(struct dentry *dentry)
+{ }
+
+static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
+ size_t len, loff_t *ppos)
+{
+ return -ENODEV;
+}
+
+static inline ssize_t debugfs_attr_write(struct file *file,
+ const char __user *buf,
+ size_t len, loff_t *ppos)
+{
+ return -ENODEV;
+}
+
+static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
+ struct dentry *new_dir, char *new_name)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
+ struct dentry *parent,
+ u8 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
+ struct dentry *parent,
+ u16 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
+ struct dentry *parent,
+ u32 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
+ struct dentry *parent,
+ u64 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_ulong(const char *name,
+ umode_t mode,
+ struct dentry *parent,
+ unsigned long *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
+ struct dentry *parent,
+ u8 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
+ struct dentry *parent,
+ u16 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
+ struct dentry *parent,
+ u32 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
+ struct dentry *parent,
+ u64 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
+ struct dentry *parent,
+ size_t *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
+ struct dentry *parent, atomic_t *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
+ struct dentry *parent,
+ bool *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
+ struct dentry *parent,
+ struct debugfs_blob_wrapper *blob)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_regset32(const char *name,
+ umode_t mode, struct dentry *parent,
+ struct debugfs_regset32 *regset)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+ int nregs, void __iomem *base, char *prefix)
+{
+}
+
+static inline bool debugfs_initialized(void)
+{
+ return false;
+}
+
+static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
+ struct dentry *parent,
+ u32 *array, u32 elements)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
+ const char *name,
+ struct dentry *parent,
+ int (*read_fn)(struct seq_file *s,
+ void *data))
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline ssize_t debugfs_read_file_bool(struct file *file,
+ char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ return -ENODEV;
+}
+
+static inline ssize_t debugfs_write_file_bool(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ return -ENODEV;
+}
+
+#endif
+
+#endif