Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 704 insertions, 0 deletions

diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
new file mode 100644
index 000000000..18f1c6074
--- /dev/null
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -0,0 +1,704 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Register map access API - debugfs
+//
+// Copyright 2011 Wolfson Microelectronics plc
+//
+// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/idr.h>
+
+#include "internal.h"
+
+struct regmap_debugfs_node {
+	struct regmap *map;
+	struct list_head link;
+};
+
+static DEFINE_IDA(dummy_ida);
+static struct dentry *regmap_debugfs_root;
+static LIST_HEAD(regmap_debugfs_early_list);
+static DEFINE_MUTEX(regmap_debugfs_early_lock);
+
+/* Calculate the length of a fixed format  */
+static size_t regmap_calc_reg_len(int max_val)
+{
+	return snprintf(NULL, 0, "%x", max_val);
+}
+
+static ssize_t regmap_name_read_file(struct file *file,
+				     char __user *user_buf, size_t count,
+				     loff_t *ppos)
+{
+	struct regmap *map = file->private_data;
+	const char *name = "nodev";
+	int ret;
+	char *buf;
+
+	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (map->dev && map->dev->driver)
+		name = map->dev->driver->name;
+
+	ret = snprintf(buf, PAGE_SIZE, "%s\n", name);
+	if (ret >= PAGE_SIZE) {
+		kfree(buf);
+		return ret;
+	}
+
+	ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
+	kfree(buf);
+	return ret;
+}
+
+static const struct file_operations regmap_name_fops = {
+	.open = simple_open,
+	.read = regmap_name_read_file,
+	.llseek = default_llseek,
+};
+
+static void regmap_debugfs_free_dump_cache(struct regmap *map)
+{
+	struct regmap_debugfs_off_cache *c;
+
+	while (!list_empty(&map->debugfs_off_cache)) {
+		c = list_first_entry(&map->debugfs_off_cache,
+				     struct regmap_debugfs_off_cache,
+				     list);
+		list_del(&c->list);
+		kfree(c);
+	}
+}
+
+static bool regmap_printable(struct regmap *map, unsigned int reg)
+{
+	if (regmap_precious(map, reg))
+		return false;
+
+	if (!regmap_readable(map, reg) && !regmap_cached(map, reg))
+		return false;
+
+	return true;
+}
+
+/*
+ * Work out where the start offset maps into register numbers, bearing
+ * in mind that we suppress hidden registers.
+ */
+static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
+						  unsigned int base,
+						  loff_t from,
+						  loff_t *pos)
+{
+	struct regmap_debugfs_off_cache *c = NULL;
+	loff_t p = 0;
+	unsigned int i, ret;
+	unsigned int fpos_offset;
+	unsigned int reg_offset;
+
+	/* Suppress the cache if we're using a subrange */
+	if (base)
+		return base;
+
+	/*
+	 * If we don't have a cache build one so we don't have to do a
+	 * linear scan each time.
+	 */
+	mutex_lock(&map->cache_lock);
+	i = base;
+	if (list_empty(&map->debugfs_off_cache)) {
+		for (; i <= map->max_register; i += map->reg_stride) {
+			/* Skip unprinted registers, closing off cache entry */
+			if (!regmap_printable(map, i)) {
+				if (c) {
+					c->max = p - 1;
+					c->max_reg = i - map->reg_stride;
+					list_add_tail(&c->list,
+						      &map->debugfs_off_cache);
+					c = NULL;
+				}
+
+				continue;
+			}
+
+			/* No cache entry?  Start a new one */
+			if (!c) {
+				c = kzalloc_obj(*c);
+				if (!c) {
+					regmap_debugfs_free_dump_cache(map);
+					mutex_unlock(&map->cache_lock);
+					return base;
+				}
+				c->min = p;
+				c->base_reg = i;
+			}
+
+			p += map->debugfs_tot_len;
+		}
+	}
+
+	/* Close the last entry off if we didn't scan beyond it */
+	if (c) {
+		c->max = p - 1;
+		c->max_reg = i - map->reg_stride;
+		list_add_tail(&c->list,
+			      &map->debugfs_off_cache);
+	}
+
+	/*
+	 * This should never happen; we return above if we fail to
+	 * allocate and we should never be in this code if there are
+	 * no registers at all.
+	 */
+	WARN_ON(list_empty(&map->debugfs_off_cache));
+	ret = base;
+
+	/* Find the relevant block:offset */
+	list_for_each_entry(c, &map->debugfs_off_cache, list) {
+		if (from >= c->min && from <= c->max) {
+			fpos_offset = from - c->min;
+			reg_offset = fpos_offset / map->debugfs_tot_len;
+			*pos = c->min + (reg_offset * map->debugfs_tot_len);
+			mutex_unlock(&map->cache_lock);
+			return c->base_reg + (reg_offset * map->reg_stride);
+		}
+
+		*pos = c->max;
+		ret = c->max_reg;
+	}
+	mutex_unlock(&map->cache_lock);
+
+	return ret;
+}
+
+static inline void regmap_calc_tot_len(struct regmap *map,
+				       void *buf, size_t count)
+{
+	/* Calculate the length of a fixed format  */
+	if (!map->debugfs_tot_len) {
+		map->debugfs_reg_len = regmap_calc_reg_len(map->max_register);
+		map->debugfs_val_len = 2 * map->format.val_bytes;
+		map->debugfs_tot_len = map->debugfs_reg_len +
+			map->debugfs_val_len + 3;      /* : \n */
+	}
+}
+
+static int regmap_next_readable_reg(struct regmap *map, int reg)
+{
+	struct regmap_debugfs_off_cache *c;
+	int ret = -EINVAL;
+
+	if (regmap_printable(map, reg + map->reg_stride)) {
+		ret = reg + map->reg_stride;
+	} else {
+		mutex_lock(&map->cache_lock);
+		list_for_each_entry(c, &map->debugfs_off_cache, list) {
+			if (reg > c->max_reg)
+				continue;
+			if (reg < c->base_reg) {
+				ret = c->base_reg;
+				break;
+			}
+		}
+		mutex_unlock(&map->cache_lock);
+	}
+	return ret;
+}
+
+static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from,
+				   unsigned int to, char __user *user_buf,
+				   size_t count, loff_t *ppos)
+{
+	size_t buf_pos = 0;
+	loff_t p = *ppos;
+	ssize_t ret;
+	int i;
+	char *buf;
+	unsigned int val, start_reg;
+
+	if (*ppos < 0 || !count)
+		return -EINVAL;
+
+	if (count > (PAGE_SIZE << MAX_PAGE_ORDER))
+		count = PAGE_SIZE << MAX_PAGE_ORDER;
+
+	buf = kmalloc(count, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	regmap_calc_tot_len(map, buf, count);
+
+	/* Work out which register we're starting at */
+	start_reg = regmap_debugfs_get_dump_start(map, from, *ppos, &p);
+
+	for (i = start_reg; i >= 0 && i <= to;
+	     i = regmap_next_readable_reg(map, i)) {
+
+		/* If we're in the region the user is trying to read */
+		if (p >= *ppos) {
+			/* ...but not beyond it */
+			if (buf_pos + map->debugfs_tot_len > count)
+				break;
+
+			/* Format the register */
+			snprintf(buf + buf_pos, count - buf_pos, "%.*x: ",
+				 map->debugfs_reg_len, i - from);
+			buf_pos += map->debugfs_reg_len + 2;
+
+			/* Format the value, write all X if we can't read */
+			ret = regmap_read(map, i, &val);
+			if (ret == 0)
+				snprintf(buf + buf_pos, count - buf_pos,
+					 "%.*x", map->debugfs_val_len, val);
+			else
+				memset(buf + buf_pos, 'X',
+				       map->debugfs_val_len);
+			buf_pos += 2 * map->format.val_bytes;
+
+			buf[buf_pos++] = '\n';
+		}
+		p += map->debugfs_tot_len;
+	}
+
+	ret = buf_pos;
+
+	if (copy_to_user(user_buf, buf, buf_pos)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	*ppos += buf_pos;
+
+out:
+	kfree(buf);
+	return ret;
+}
+
+static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf,
+				    size_t count, loff_t *ppos)
+{
+	struct regmap *map = file->private_data;
+
+	return regmap_read_debugfs(map, 0, map->max_register, user_buf,
+				   count, ppos);
+}
+
+#undef REGMAP_ALLOW_WRITE_DEBUGFS
+#ifdef REGMAP_ALLOW_WRITE_DEBUGFS
+/*
+ * This can be dangerous especially when we have clients such as
+ * PMICs, therefore don't provide any real compile time configuration option
+ * for this feature, people who want to use this will need to modify
+ * the source code directly.
+ */
+static ssize_t regmap_map_write_file(struct file *file,
+				     const char __user *user_buf,
+				     size_t count, loff_t *ppos)
+{
+	char buf[32];
+	size_t buf_size;
+	char *start = buf;
+	unsigned long reg, value;
+	struct regmap *map = file->private_data;
+	int ret;
+
+	buf_size = min(count, (sizeof(buf)-1));
+	if (copy_from_user(buf, user_buf, buf_size))
+		return -EFAULT;
+	buf[buf_size] = 0;
+
+	while (*start == ' ')
+		start++;
+	reg = simple_strtoul(start, &start, 16);
+	while (*start == ' ')
+		start++;
+	if (kstrtoul(start, 16, &value))
+		return -EINVAL;
+
+	/* Userspace has been fiddling around behind the kernel's back */
+	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+
+	ret = regmap_write(map, reg, value);
+	if (ret < 0)
+		return ret;
+	return buf_size;
+}
+#else
+#define regmap_map_write_file NULL
+#endif
+
+static const struct file_operations regmap_map_fops = {
+	.open = simple_open,
+	.read = regmap_map_read_file,
+	.write = regmap_map_write_file,
+	.llseek = default_llseek,
+};
+
+static ssize_t regmap_range_read_file(struct file *file, char __user *user_buf,
+				      size_t count, loff_t *ppos)
+{
+	struct regmap_range_node *range = file->private_data;
+	struct regmap *map = range->map;
+
+	return regmap_read_debugfs(map, range->range_min, range->range_max,
+				   user_buf, count, ppos);
+}
+
+static const struct file_operations regmap_range_fops = {
+	.open = simple_open,
+	.read = regmap_range_read_file,
+	.llseek = default_llseek,
+};
+
+static ssize_t regmap_reg_ranges_read_file(struct file *file,
+					   char __user *user_buf, size_t count,
+					   loff_t *ppos)
+{
+	struct regmap *map = file->private_data;
+	struct regmap_debugfs_off_cache *c;
+	loff_t p = 0;
+	size_t buf_pos = 0;
+	char *buf;
+	char *entry;
+	int ret;
+	unsigned int entry_len;
+
+	if (*ppos < 0 || !count)
+		return -EINVAL;
+
+	if (count > (PAGE_SIZE << MAX_PAGE_ORDER))
+		count = PAGE_SIZE << MAX_PAGE_ORDER;
+
+	buf = kmalloc(count, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	entry = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!entry) {
+		kfree(buf);
+		return -ENOMEM;
+	}
+
+	/* While we are at it, build the register dump cache
+	 * now so the read() operation on the `registers' file
+	 * can benefit from using the cache.  We do not care
+	 * about the file position information that is contained
+	 * in the cache, just about the actual register blocks */
+	regmap_calc_tot_len(map, buf, count);
+	regmap_debugfs_get_dump_start(map, 0, *ppos, &p);
+
+	/* Reset file pointer as the fixed-format of the `registers'
+	 * file is not compatible with the `range' file */
+	p = 0;
+	mutex_lock(&map->cache_lock);
+	list_for_each_entry(c, &map->debugfs_off_cache, list) {
+		entry_len = snprintf(entry, PAGE_SIZE, "%x-%x\n",
+				     c->base_reg, c->max_reg);
+		if (p >= *ppos) {
+			if (buf_pos + entry_len > count)
+				break;
+			memcpy(buf + buf_pos, entry, entry_len);
+			buf_pos += entry_len;
+		}
+		p += entry_len;
+	}
+	mutex_unlock(&map->cache_lock);
+
+	kfree(entry);
+	ret = buf_pos;
+
+	if (copy_to_user(user_buf, buf, buf_pos)) {
+		ret = -EFAULT;
+		goto out_buf;
+	}
+
+	*ppos += buf_pos;
+out_buf:
+	kfree(buf);
+	return ret;
+}
+
+static const struct file_operations regmap_reg_ranges_fops = {
+	.open = simple_open,
+	.read = regmap_reg_ranges_read_file,
+	.llseek = default_llseek,
+};
+
+static int regmap_access_show(struct seq_file *s, void *ignored)
+{
+	struct regmap *map = s->private;
+	int i, reg_len;
+
+	reg_len = regmap_calc_reg_len(map->max_register);
+
+	for (i = 0; i <= map->max_register; i += map->reg_stride) {
+		/* Ignore registers which are neither readable nor writable */
+		if (!regmap_readable(map, i) && !regmap_writeable(map, i))
+			continue;
+
+		/* Format the register */
+		seq_printf(s, "%.*x: %c %c %c %c\n", reg_len, i,
+			   regmap_readable(map, i) ? 'y' : 'n',
+			   regmap_writeable(map, i) ? 'y' : 'n',
+			   regmap_volatile(map, i) ? 'y' : 'n',
+			   regmap_precious(map, i) ? 'y' : 'n');
+	}
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(regmap_access);
+
+static ssize_t regmap_cache_only_write_file(struct file *file,
+					    const char __user *user_buf,
+					    size_t count, loff_t *ppos)
+{
+	struct regmap *map = container_of(file->private_data,
+					  struct regmap, cache_only);
+	bool new_val, require_sync = false;
+	int err;
+
+	err = kstrtobool_from_user(user_buf, count, &new_val);
+	/* Ignore malforned data like debugfs_write_file_bool() */
+	if (err)
+		return count;
+
+	map->lock(map->lock_arg);
+
+	if (new_val && !map->cache_only) {
+		dev_warn(map->dev, "debugfs cache_only=Y forced\n");
+		add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+	} else if (!new_val && map->cache_only) {
+		dev_warn(map->dev, "debugfs cache_only=N forced: syncing cache\n");
+		require_sync = true;
+	}
+	map->cache_only = new_val;
+
+	map->unlock(map->lock_arg);
+
+	if (require_sync) {
+		err = regcache_sync(map);
+		if (err)
+			dev_err(map->dev, "Failed to sync cache %d\n", err);
+	}
+
+	return count;
+}
+
+static const struct file_operations regmap_cache_only_fops = {
+	.open = simple_open,
+	.read = debugfs_read_file_bool,
+	.write = regmap_cache_only_write_file,
+};
+
+static ssize_t regmap_cache_bypass_write_file(struct file *file,
+					      const char __user *user_buf,
+					      size_t count, loff_t *ppos)
+{
+	struct regmap *map = container_of(file->private_data,
+					  struct regmap, cache_bypass);
+	bool new_val;
+	int err;
+
+	err = kstrtobool_from_user(user_buf, count, &new_val);
+	/* Ignore malforned data like debugfs_write_file_bool() */
+	if (err)
+		return count;
+
+	map->lock(map->lock_arg);
+
+	if (new_val && !map->cache_bypass) {
+		dev_warn(map->dev, "debugfs cache_bypass=Y forced\n");
+		add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+	} else if (!new_val && map->cache_bypass) {
+		dev_warn(map->dev, "debugfs cache_bypass=N forced\n");
+	}
+	map->cache_bypass = new_val;
+
+	map->unlock(map->lock_arg);
+
+	return count;
+}
+
+static const struct file_operations regmap_cache_bypass_fops = {
+	.open = simple_open,
+	.read = debugfs_read_file_bool,
+	.write = regmap_cache_bypass_write_file,
+};
+
+void regmap_debugfs_init(struct regmap *map)
+{
+	struct rb_node *next;
+	struct regmap_range_node *range_node;
+	const char *devname = "dummy";
+	const char *name = map->name;
+	int id;
+
+	/*
+	 * Userspace can initiate reads from the hardware over debugfs.
+	 * Normally internal regmap structures and buffers are protected with
+	 * a mutex or a spinlock, but if the regmap owner decided to disable
+	 * all locking mechanisms, this is no longer the case. For safety:
+	 * don't create the debugfs entries if locking is disabled.
+	 */
+	if (map->debugfs_disable) {
+		dev_dbg(map->dev, "regmap locking disabled - not creating debugfs entries\n");
+		return;
+	}
+
+	/* If we don't have the debugfs root yet, postpone init */
+	if (!regmap_debugfs_root) {
+		struct regmap_debugfs_node *node;
+		node = kzalloc_obj(*node);
+		if (!node)
+			return;
+		node->map = map;
+		mutex_lock(&regmap_debugfs_early_lock);
+		list_add(&node->link, &regmap_debugfs_early_list);
+		mutex_unlock(&regmap_debugfs_early_lock);
+		return;
+	}
+
+	INIT_LIST_HEAD(&map->debugfs_off_cache);
+	mutex_init(&map->cache_lock);
+	map->debugfs_dummy_id = -1;
+
+	if (map->dev)
+		devname = dev_name(map->dev);
+
+	if (name) {
+		if (!map->debugfs_name) {
+			map->debugfs_name = kasprintf(GFP_KERNEL, "%s-%s",
+					      devname, name);
+			if (!map->debugfs_name)
+				return;
+		}
+		name = map->debugfs_name;
+	} else {
+		name = devname;
+	}
+
+	if (!strcmp(name, "dummy")) {
+		kfree(map->debugfs_name);
+		id = ida_alloc(&dummy_ida, GFP_KERNEL);
+		if (id < 0)
+			return;
+		map->debugfs_name = kasprintf(GFP_KERNEL, "dummy%d", id);
+		if (!map->debugfs_name) {
+			ida_free(&dummy_ida, id);
+			return;
+		}
+		map->debugfs_dummy_id = id;
+		name = map->debugfs_name;
+	}
+
+	map->debugfs = debugfs_create_dir(name, regmap_debugfs_root);
+
+	debugfs_create_file("name", 0400, map->debugfs,
+			    map, &regmap_name_fops);
+
+	debugfs_create_file("range", 0400, map->debugfs,
+			    map, &regmap_reg_ranges_fops);
+
+	if (map->max_register || regmap_readable(map, 0)) {
+		umode_t registers_mode;
+
+#if defined(REGMAP_ALLOW_WRITE_DEBUGFS)
+		registers_mode = 0600;
+#else
+		registers_mode = 0400;
+#endif
+
+		debugfs_create_file("registers", registers_mode, map->debugfs,
+				    map, &regmap_map_fops);
+		debugfs_create_file("access", 0400, map->debugfs,
+				    map, &regmap_access_fops);
+	}
+
+	if (map->cache_type) {
+		debugfs_create_file("cache_only", 0600, map->debugfs,
+				    &map->cache_only, &regmap_cache_only_fops);
+		debugfs_create_bool("cache_dirty", 0400, map->debugfs,
+				    &map->cache_dirty);
+		debugfs_create_file("cache_bypass", 0600, map->debugfs,
+				    &map->cache_bypass,
+				    &regmap_cache_bypass_fops);
+	}
+
+	/*
+	 * This could interfere with driver operation. Therefore, don't provide
+	 * any real compile time configuration option for this feature. One will
+	 * have to modify the source code directly in order to use it.
+	 */
+#undef REGMAP_ALLOW_FORCE_WRITE_FIELD_DEBUGFS
+#ifdef REGMAP_ALLOW_FORCE_WRITE_FIELD_DEBUGFS
+	debugfs_create_bool("force_write_field", 0600, map->debugfs,
+			    &map->force_write_field);
+#endif
+
+	next = rb_first(&map->range_tree);
+	while (next) {
+		range_node = rb_entry(next, struct regmap_range_node, node);
+
+		if (range_node->name)
+			debugfs_create_file(range_node->name, 0400,
+					    map->debugfs, range_node,
+					    &regmap_range_fops);
+
+		next = rb_next(&range_node->node);
+	}
+
+	if (map->cache_ops && map->cache_ops->debugfs_init)
+		map->cache_ops->debugfs_init(map);
+}
+
+void regmap_debugfs_exit(struct regmap *map)
+{
+	if (map->debugfs) {
+		debugfs_remove_recursive(map->debugfs);
+		mutex_lock(&map->cache_lock);
+		regmap_debugfs_free_dump_cache(map);
+		mutex_unlock(&map->cache_lock);
+		if (map->debugfs_dummy_id >= 0) {
+			ida_free(&dummy_ida, map->debugfs_dummy_id);
+			map->debugfs_dummy_id = -1;
+		}
+		kfree(map->debugfs_name);
+		map->debugfs_name = NULL;
+	} else {
+		struct regmap_debugfs_node *node, *tmp;
+
+		mutex_lock(&regmap_debugfs_early_lock);
+		list_for_each_entry_safe(node, tmp, &regmap_debugfs_early_list,
+					 link) {
+			if (node->map == map) {
+				list_del(&node->link);
+				kfree(node);
+			}
+		}
+		mutex_unlock(&regmap_debugfs_early_lock);
+	}
+}
+
+void regmap_debugfs_initcall(void)
+{
+	struct regmap_debugfs_node *node, *tmp;
+
+	regmap_debugfs_root = debugfs_create_dir("regmap", NULL);
+
+	mutex_lock(&regmap_debugfs_early_lock);
+	list_for_each_entry_safe(node, tmp, &regmap_debugfs_early_list, link) {
+		regmap_debugfs_init(node->map);
+		list_del(&node->link);
+		kfree(node);
+	}
+	mutex_unlock(&regmap_debugfs_early_lock);
+}