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
  ...

mm/backing-dev.c

@@ -103,39 +103,25 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v)
 }
 DEFINE_SHOW_ATTRIBUTE(bdi_debug_stats);
 
-static int bdi_debug_register(struct backing_dev_info *bdi, const char *name)
+static void bdi_debug_register(struct backing_dev_info *bdi, const char *name)
 {
-	if (!bdi_debug_root)
-		return -ENOMEM;
-
 	bdi->debug_dir = debugfs_create_dir(name, bdi_debug_root);
-	if (!bdi->debug_dir)
-		return -ENOMEM;
 
-	bdi->debug_stats = debugfs_create_file("stats", 0444, bdi->debug_dir,
-					       bdi, &bdi_debug_stats_fops);
-	if (!bdi->debug_stats) {
-		debugfs_remove(bdi->debug_dir);
-		bdi->debug_dir = NULL;
-		return -ENOMEM;
-	}
-
-	return 0;
+	debugfs_create_file("stats", 0444, bdi->debug_dir, bdi,
+			    &bdi_debug_stats_fops);
 }
 
 static void bdi_debug_unregister(struct backing_dev_info *bdi)
 {
-	debugfs_remove(bdi->debug_stats);
-	debugfs_remove(bdi->debug_dir);
+	debugfs_remove_recursive(bdi->debug_dir);
 }
 #else
 static inline void bdi_debug_init(void)
 {
 }
-static inline int bdi_debug_register(struct backing_dev_info *bdi,
+static inline void bdi_debug_register(struct backing_dev_info *bdi,
 				      const char *name)
 {
-	return 0;
 }
 static inline void bdi_debug_unregister(struct backing_dev_info *bdi)
 {

mm/cleancache.c

@@ -304,8 +304,7 @@ static int __init init_cleancache(void)
 {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *root = debugfs_create_dir("cleancache", NULL);
-	if (root == NULL)
-		return -ENXIO;
+
 	debugfs_create_u64("succ_gets", 0444, root, &cleancache_succ_gets);
 	debugfs_create_u64("failed_gets", 0444, root, &cleancache_failed_gets);
 	debugfs_create_u64("puts", 0444, root, &cleancache_puts);

mm/hwpoison-inject.c

@@ -77,63 +77,40 @@ static void pfn_inject_exit(void)
 
 static int pfn_inject_init(void)
 {
-	struct dentry *dentry;
-
 	hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
-	if (hwpoison_dir == NULL)
-		return -ENOMEM;
 
 	/*
 	 * Note that the below poison/unpoison interfaces do not involve
 	 * hardware status change, hence do not require hardware support.
 	 * They are mainly for testing hwpoison in software level.
 	 */
-	dentry = debugfs_create_file("corrupt-pfn", 0200, hwpoison_dir,
-					  NULL, &hwpoison_fops);
-	if (!dentry)
-		goto fail;
+	debugfs_create_file("corrupt-pfn", 0200, hwpoison_dir, NULL,
+			    &hwpoison_fops);
 
-	dentry = debugfs_create_file("unpoison-pfn", 0200, hwpoison_dir,
-				     NULL, &unpoison_fops);
-	if (!dentry)
-		goto fail;
+	debugfs_create_file("unpoison-pfn", 0200, hwpoison_dir, NULL,
+			    &unpoison_fops);
 
-	dentry = debugfs_create_u32("corrupt-filter-enable", 0600,
-				    hwpoison_dir, &hwpoison_filter_enable);
-	if (!dentry)
-		goto fail;
+	debugfs_create_u32("corrupt-filter-enable", 0600, hwpoison_dir,
+			   &hwpoison_filter_enable);
 
-	dentry = debugfs_create_u32("corrupt-filter-dev-major", 0600,
-				    hwpoison_dir, &hwpoison_filter_dev_major);
-	if (!dentry)
-		goto fail;
+	debugfs_create_u32("corrupt-filter-dev-major", 0600, hwpoison_dir,
+			   &hwpoison_filter_dev_major);
 
-	dentry = debugfs_create_u32("corrupt-filter-dev-minor", 0600,
-				    hwpoison_dir, &hwpoison_filter_dev_minor);
-	if (!dentry)
-		goto fail;
+	debugfs_create_u32("corrupt-filter-dev-minor", 0600, hwpoison_dir,
+			   &hwpoison_filter_dev_minor);
 
-	dentry = debugfs_create_u64("corrupt-filter-flags-mask", 0600,
-				    hwpoison_dir, &hwpoison_filter_flags_mask);
-	if (!dentry)
-		goto fail;
+	debugfs_create_u64("corrupt-filter-flags-mask", 0600, hwpoison_dir,
+			   &hwpoison_filter_flags_mask);
 
-	dentry = debugfs_create_u64("corrupt-filter-flags-value", 0600,
-				    hwpoison_dir, &hwpoison_filter_flags_value);
-	if (!dentry)
-		goto fail;
+	debugfs_create_u64("corrupt-filter-flags-value", 0600, hwpoison_dir,
+			   &hwpoison_filter_flags_value);
 
 #ifdef CONFIG_MEMCG
-	dentry = debugfs_create_u64("corrupt-filter-memcg", 0600,
-				    hwpoison_dir, &hwpoison_filter_memcg);
-	if (!dentry)
-		goto fail;
+	debugfs_create_u64("corrupt-filter-memcg", 0600, hwpoison_dir,
+			   &hwpoison_filter_memcg);
 #endif
 
 	return 0;
-fail:
-	pfn_inject_exit();
-	return -ENOMEM;
 }
 
 module_init(pfn_inject_init);

mm/kmemleak.c

@@ -2105,14 +2105,9 @@ void __init kmemleak_init(void)
  */
 static int __init kmemleak_late_init(void)
 {
-	struct dentry *dentry;
-
 	kmemleak_initialized = 1;
 
-	dentry = debugfs_create_file("kmemleak", 0644, NULL, NULL,
-				     &kmemleak_fops);
-	if (!dentry)
-		pr_warn("Failed to create the debugfs kmemleak file\n");
+	debugfs_create_file("kmemleak", 0644, NULL, NULL, &kmemleak_fops);
 
 	if (kmemleak_error) {
 		/*

mm/zsmalloc.c

@@ -575,8 +575,6 @@ static void __init zs_stat_init(void)
 	}
 
 	zs_stat_root = debugfs_create_dir("zsmalloc", NULL);
-	if (!zs_stat_root)
-		pr_warn("debugfs 'zsmalloc' stat dir creation failed\n");
 }
 
 static void __exit zs_stat_exit(void)
@@ -647,29 +645,15 @@ DEFINE_SHOW_ATTRIBUTE(zs_stats_size);
 
 static void zs_pool_stat_create(struct zs_pool *pool, const char *name)
 {
-	struct dentry *entry;
-
 	if (!zs_stat_root) {
 		pr_warn("no root stat dir, not creating <%s> stat dir\n", name);
 		return;
 	}
 
-	entry = debugfs_create_dir(name, zs_stat_root);
-	if (!entry) {
-		pr_warn("debugfs dir <%s> creation failed\n", name);
-		return;
-	}
-	pool->stat_dentry = entry;
+	pool->stat_dentry = debugfs_create_dir(name, zs_stat_root);
 
-	entry = debugfs_create_file("classes", S_IFREG | 0444,
-				    pool->stat_dentry, pool,
-				    &zs_stats_size_fops);
-	if (!entry) {
-		pr_warn("%s: debugfs file entry <%s> creation failed\n",
-				name, "classes");
-		debugfs_remove_recursive(pool->stat_dentry);
-		pool->stat_dentry = NULL;
-	}
+	debugfs_create_file("classes", S_IFREG | 0444, pool->stat_dentry, pool,
+			    &zs_stats_size_fops);
 }
 
 static void zs_pool_stat_destroy(struct zs_pool *pool)

mm/zswap.c

@@ -1253,8 +1253,6 @@ static int __init zswap_debugfs_init(void)
 		return -ENODEV;
 
 	zswap_debugfs_root = debugfs_create_dir("zswap", NULL);
-	if (!zswap_debugfs_root)
-		return -ENOMEM;
 
 	debugfs_create_u64("pool_limit_hit", 0444,
 			   zswap_debugfs_root, &zswap_pool_limit_hit);