Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...

2 files changed, 32 insertions, 16 deletions

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index ddd708b09fa1..93e4ca6b2ad7 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -997,25 +997,19 @@ static const struct file_operations u32_array_fops = {
  * @array as data. If the @mode variable is so set it can be read from.
  * Writing is not supported. Seek within the file is also not supported.
  * Once array is created its size can not be changed.
- *
- * The function returns a pointer to dentry on success. If an error occurs,
- * %ERR_PTR(-ERROR) or NULL will be returned. If debugfs is not enabled in
- * the kernel, the value %ERR_PTR(-ENODEV) will be returned.
  */
-struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
-					    struct dentry *parent,
-					    u32 *array, u32 elements)
+void debugfs_create_u32_array(const char *name, umode_t mode,
+			      struct dentry *parent, u32 *array, u32 elements)
 {
 	struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
 
 	if (data == NULL)
-		return NULL;
+		return;
 
 	data->array = array;
 	data->elements = elements;
 
-	return debugfs_create_file_unsafe(name, mode, parent, data,
-					&u32_array_fops);
+	debugfs_create_file_unsafe(name, mode, parent, data, &u32_array_fops);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
 
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 1e444fe1f778..042b688ed124 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -2,13 +2,16 @@
 /*
  *  inode.c - part of debugfs, a tiny little debug file system
  *
- *  Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
+ *  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/mount.h>
@@ -285,15 +288,17 @@ static struct dentry *start_creating(const char *name, struct dentry *parent)
 	struct dentry *dentry;
 	int error;
 
-	pr_debug("debugfs: creating file '%s'\n",name);
+	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)
+	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
@@ -306,6 +311,12 @@ static struct dentry *start_creating(const char *name, struct dentry *parent)
 	inode_lock(d_inode(parent));
 	dentry = lookup_one_len(name, parent, strlen(name));
 	if (!IS_ERR(dentry) && d_really_is_positive(dentry)) {
+		if (d_is_dir(dentry))
+			pr_err("Directory '%s' with parent '%s' already present!\n",
+			       name, parent->d_name.name);
+		else
+			pr_err("File '%s' in directory '%s' already present!\n",
+			       name, parent->d_name.name);
 		dput(dentry);
 		dentry = ERR_PTR(-EEXIST);
 	}
@@ -349,8 +360,11 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
 		return dentry;
 
 	inode = debugfs_get_inode(dentry->d_sb);
-	if (unlikely(!inode))
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create file '%s'\n",
+		       name);
 		return failed_creating(dentry);
+	}
 
 	inode->i_mode = mode;
 	inode->i_private = data;
@@ -511,8 +525,11 @@ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
 		return dentry;
 
 	inode = debugfs_get_inode(dentry->d_sb);
-	if (unlikely(!inode))
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create directory '%s'\n",
+		       name);
 		return failed_creating(dentry);
+	}
 
 	inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
 	inode->i_op = &simple_dir_inode_operations;
@@ -550,8 +567,11 @@ struct dentry *debugfs_create_automount(const char *name,
 		return dentry;
 
 	inode = debugfs_get_inode(dentry->d_sb);
-	if (unlikely(!inode))
+	if (unlikely(!inode)) {
+		pr_err("out of free dentries, can not create automount '%s'\n",
+		       name);
 		return failed_creating(dentry);
+	}
 
 	make_empty_dir_inode(inode);
 	inode->i_flags |= S_AUTOMOUNT;
@@ -606,6 +626,8 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
 
 	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 failed_creating(dentry);
 	}