2 files changed, 125 insertions, 101 deletions

diff --git a/kernel/fs/debugfs/file.c b/kernel/fs/debugfs/file.c
index 830a7e76f..d2ba12e23 100644
--- a/kernel/fs/debugfs/file.c
+++ b/kernel/fs/debugfs/file.c
@@ -17,7 +17,6 @@
 #include <linux/fs.h>
 #include <linux/seq_file.h>
 #include <linux/pagemap.h>
-#include <linux/namei.h>
 #include <linux/debugfs.h>
 #include <linux/io.h>
 #include <linux/slab.h>
@@ -43,16 +42,21 @@ const struct file_operations debugfs_file_operations = {
 	.llseek =	noop_llseek,
 };
 
-static void *debugfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+static struct dentry *debugfs_create_mode(const char *name, umode_t mode,
+					  struct dentry *parent, void *value,
+				          const struct file_operations *fops,
+				          const struct file_operations *fops_ro,
+				          const struct file_operations *fops_wo)
 {
-	nd_set_link(nd, d_inode(dentry)->i_private);
-	return NULL;
-}
+	/* if there are no write bits set, make read only */
+	if (!(mode & S_IWUGO))
+		return debugfs_create_file(name, mode, parent, value, fops_ro);
+	/* if there are no read bits set, make write only */
+	if (!(mode & S_IRUGO))
+		return debugfs_create_file(name, mode, parent, value, fops_wo);
 
-const struct inode_operations debugfs_link_operations = {
-	.readlink       = generic_readlink,
-	.follow_link    = debugfs_follow_link,
-};
+	return debugfs_create_file(name, mode, parent, value, fops);
+}
 
 static int debugfs_u8_set(void *data, u64 val)
 {
@@ -95,14 +99,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
 				 struct dentry *parent, u8 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u8_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u8_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_u8);
+	return debugfs_create_mode(name, mode, parent, value, &fops_u8,
+				   &fops_u8_ro, &fops_u8_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u8);
 
@@ -147,14 +145,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n");
 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
 				  struct dentry *parent, u16 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u16_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u16_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_u16);
+	return debugfs_create_mode(name, mode, parent, value, &fops_u16,
+				   &fops_u16_ro, &fops_u16_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u16);
 
@@ -199,14 +191,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
 				 struct dentry *parent, u32 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u32_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u32_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_u32);
+	return debugfs_create_mode(name, mode, parent, value, &fops_u32,
+				   &fops_u32_ro, &fops_u32_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u32);
 
@@ -252,17 +238,59 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
 				 struct dentry *parent, u64 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u64_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_u64_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_u64);
+	return debugfs_create_mode(name, mode, parent, value, &fops_u64,
+				   &fops_u64_ro, &fops_u64_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u64);
 
+static int debugfs_ulong_set(void *data, u64 val)
+{
+	*(unsigned long *)data = val;
+	return 0;
+}
+
+static int debugfs_ulong_get(void *data, u64 *val)
+{
+	*val = *(unsigned long *)data;
+	return 0;
+}
+DEFINE_SIMPLE_ATTRIBUTE(fops_ulong, debugfs_ulong_get, debugfs_ulong_set, "%llu\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_ulong_ro, debugfs_ulong_get, NULL, "%llu\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_ulong_wo, NULL, debugfs_ulong_set, "%llu\n");
+
+/**
+ * debugfs_create_ulong - create a debugfs file that is used to read and write
+ * an unsigned long value.
+ * @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.
+ * @value: a pointer to the variable that the file should read to and write
+ *         from.
+ *
+ * This function creates a file in debugfs with the given name that
+ * contains the value of the variable @value.  If the @mode variable is so
+ * set, it can be read from, and written to.
+ *
+ * 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, %NULL will be returned.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned.  It is not wise to check for this value, but rather, check for
+ * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
+ * code.
+ */
+struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
+				    struct dentry *parent, unsigned long *value)
+{
+	return debugfs_create_mode(name, mode, parent, value, &fops_ulong,
+				   &fops_ulong_ro, &fops_ulong_wo);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_ulong);
+
 DEFINE_SIMPLE_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n");
 DEFINE_SIMPLE_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n");
 DEFINE_SIMPLE_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n");
@@ -276,6 +304,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n");
 DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n");
 
 DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_x64_ro, debugfs_u64_get, NULL, "0x%016llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_x64_wo, NULL, debugfs_u64_set, "0x%016llx\n");
 
 /*
  * debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value
@@ -298,14 +328,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n
 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
 				 struct dentry *parent, u8 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_x8_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_x8_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_x8);
+	return debugfs_create_mode(name, mode, parent, value, &fops_x8,
+				   &fops_x8_ro, &fops_x8_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_x8);
 
@@ -322,14 +346,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_x8);
 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
 				 struct dentry *parent, u16 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_x16_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_x16_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_x16);
+	return debugfs_create_mode(name, mode, parent, value, &fops_x16,
+				   &fops_x16_ro, &fops_x16_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_x16);
 
@@ -346,14 +364,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_x16);
 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
 				 struct dentry *parent, u32 *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_x32_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value, &fops_x32_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_x32);
+	return debugfs_create_mode(name, mode, parent, value, &fops_x32,
+				   &fops_x32_ro, &fops_x32_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_x32);
 
@@ -370,7 +382,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_x32);
 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
 				 struct dentry *parent, u64 *value)
 {
-	return debugfs_create_file(name, mode, parent, value, &fops_x64);
+	return debugfs_create_mode(name, mode, parent, value, &fops_x64,
+				   &fops_x64_ro, &fops_x64_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_x64);
 
@@ -387,6 +400,8 @@ static int debugfs_size_t_get(void *data, u64 *val)
 }
 DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
 			"%llu\n");	/* %llu and %zu are more or less the same */
+DEFINE_SIMPLE_ATTRIBUTE(fops_size_t_ro, debugfs_size_t_get, NULL, "%llu\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_size_t_wo, NULL, debugfs_size_t_set, "%llu\n");
 
 /**
  * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
@@ -401,7 +416,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
 				     struct dentry *parent, size_t *value)
 {
-	return debugfs_create_file(name, mode, parent, value, &fops_size_t);
+	return debugfs_create_mode(name, mode, parent, value, &fops_size_t,
+				   &fops_size_t_ro, &fops_size_t_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_size_t);
 
@@ -434,24 +450,16 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set, "%lld\n");
 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
 				 struct dentry *parent, atomic_t *value)
 {
-	/* if there are no write bits set, make read only */
-	if (!(mode & S_IWUGO))
-		return debugfs_create_file(name, mode, parent, value,
-					&fops_atomic_t_ro);
-	/* if there are no read bits set, make write only */
-	if (!(mode & S_IRUGO))
-		return debugfs_create_file(name, mode, parent, value,
-					&fops_atomic_t_wo);
-
-	return debugfs_create_file(name, mode, parent, value, &fops_atomic_t);
+	return debugfs_create_mode(name, mode, parent, value, &fops_atomic_t,
+				   &fops_atomic_t_ro, &fops_atomic_t_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_atomic_t);
 
-static ssize_t read_file_bool(struct file *file, char __user *user_buf,
-			      size_t count, loff_t *ppos)
+ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
+			       size_t count, loff_t *ppos)
 {
 	char buf[3];
-	u32 *val = file->private_data;
+	bool *val = file->private_data;
 
 	if (*val)
 		buf[0] = 'Y';
@@ -461,14 +469,15 @@ static ssize_t read_file_bool(struct file *file, char __user *user_buf,
 	buf[2] = 0x00;
 	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
 }
+EXPORT_SYMBOL_GPL(debugfs_read_file_bool);
 
-static ssize_t write_file_bool(struct file *file, const 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)
 {
 	char buf[32];
 	size_t buf_size;
 	bool bv;
-	u32 *val = file->private_data;
+	bool *val = file->private_data;
 
 	buf_size = min(count, (sizeof(buf)-1));
 	if (copy_from_user(buf, user_buf, buf_size))
@@ -480,10 +489,23 @@ static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
 
 	return count;
 }
+EXPORT_SYMBOL_GPL(debugfs_write_file_bool);
 
 static const struct file_operations fops_bool = {
-	.read =		read_file_bool,
-	.write =	write_file_bool,
+	.read =		debugfs_read_file_bool,
+	.write =	debugfs_write_file_bool,
+	.open =		simple_open,
+	.llseek =	default_llseek,
+};
+
+static const struct file_operations fops_bool_ro = {
+	.read =		debugfs_read_file_bool,
+	.open =		simple_open,
+	.llseek =	default_llseek,
+};
+
+static const struct file_operations fops_bool_wo = {
+	.write =	debugfs_write_file_bool,
 	.open =		simple_open,
 	.llseek =	default_llseek,
 };
@@ -513,9 +535,10 @@ static const struct file_operations fops_bool = {
  * code.
  */
 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
-				   struct dentry *parent, u32 *value)
+				   struct dentry *parent, bool *value)
 {
-	return debugfs_create_file(name, mode, parent, value, &fops_bool);
+	return debugfs_create_mode(name, mode, parent, value, &fops_bool,
+				   &fops_bool_ro, &fops_bool_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_bool);
 
diff --git a/kernel/fs/debugfs/inode.c b/kernel/fs/debugfs/inode.c
index 12756040c..b7fcc0de0 100644
--- a/kernel/fs/debugfs/inode.c
+++ b/kernel/fs/debugfs/inode.c
@@ -44,11 +44,6 @@ static struct inode *debugfs_get_inode(struct super_block *sb)
 	return inode;
 }
 
-static inline int debugfs_positive(struct dentry *dentry)
-{
-	return d_really_is_positive(dentry) && !d_unhashed(dentry);
-}
-
 struct debugfs_mount_opts {
 	kuid_t uid;
 	kgid_t gid;
@@ -174,7 +169,7 @@ static void debugfs_evict_inode(struct inode *inode)
 	truncate_inode_pages_final(&inode->i_data);
 	clear_inode(inode);
 	if (S_ISLNK(inode->i_mode))
-		kfree(inode->i_private);
+		kfree(inode->i_link);
 }
 
 static const struct super_operations debugfs_super_operations = {
@@ -276,8 +271,12 @@ static struct dentry *start_creating(const char *name, struct dentry *parent)
 		dput(dentry);
 		dentry = ERR_PTR(-EEXIST);
 	}
-	if (IS_ERR(dentry))
+
+	if (IS_ERR(dentry)) {
 		mutex_unlock(&d_inode(parent)->i_mutex);
+		simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+	}
+
 	return dentry;
 }
 
@@ -511,8 +510,8 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
 		return failed_creating(dentry);
 	}
 	inode->i_mode = S_IFLNK | S_IRWXUGO;
-	inode->i_op = &debugfs_link_operations;
-	inode->i_private = link;
+	inode->i_op = &simple_symlink_inode_operations;
+	inode->i_link = link;
 	d_instantiate(dentry, inode);
 	return end_creating(dentry);
 }
@@ -522,7 +521,7 @@ static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
 {
 	int ret = 0;
 
-	if (debugfs_positive(dentry)) {
+	if (simple_positive(dentry)) {
 		dget(dentry);
 		if (d_is_dir(dentry))
 			ret = simple_rmdir(d_inode(parent), dentry);
@@ -538,7 +537,8 @@ static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
 /**
  * debugfs_remove - removes a file or directory from the debugfs filesystem
  * @dentry: a pointer to a the dentry of the file or directory to be
- *          removed.
+ *          removed.  If this parameter is NULL or an error value, nothing
+ *          will be done.
  *
  * This function removes a file or directory in debugfs that was previously
  * created with a call to another debugfs function (like
@@ -570,7 +570,8 @@ EXPORT_SYMBOL_GPL(debugfs_remove);
 
 /**
  * debugfs_remove_recursive - recursively removes a directory
- * @dentry: a pointer to a the dentry of the directory to be removed.
+ * @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
@@ -602,7 +603,7 @@ void debugfs_remove_recursive(struct dentry *dentry)
 	 */
 	spin_lock(&parent->d_lock);
 	list_for_each_entry(child, &parent->d_subdirs, d_child) {
-		if (!debugfs_positive(child))
+		if (!simple_positive(child))
 			continue;
 
 		/* perhaps simple_empty(child) makes more sense */
@@ -623,7 +624,7 @@ void debugfs_remove_recursive(struct dentry *dentry)
 		 * from d_subdirs. When releasing the parent->d_lock we can
 		 * no longer trust that the next pointer is valid.
 		 * Restart the loop. We'll skip this one with the
-		 * debugfs_positive() check.
+		 * simple_positive() check.
 		 */
 		goto loop;
 	}