[PATCH 35/46] debugfs: Add debugfs_create_u64()

Greg Kroah-Hartman
2007-04-27T19:09:51Z

From: Michael Ellerman <michael@ellerman.id.au>

I went to use this the other day, only to find it didn't exist.

It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick
test shows it seems to be working.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
fs/debugfs/file.c | 42 ++++++++++++++++++++++++++++++++++++++++++
include/linux/debugfs.h | 9 +++++++++
2 files changed, 51 insertions(+), 0 deletions(-)

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 682f928..2e124e0 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -179,6 +179,48 @@ struct dentry *debugfs_create_u32(const char *name, mode_t mode,
}
EXPORT_SYMBOL_GPL(debugfs_create_u32);

+static void debugfs_u64_set(void *data, u64 val)
+{
+ *(u64 *)data = val;
+}
+
+static u64 debugfs_u64_get(void *data)
+{
+ return *(u64 *)data;
+}
+DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n");
+
+/**
+ * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit 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_u64(const char *name, mode_t mode,
+ struct dentry *parent, u64 *value)
+{
+ return debugfs_create_file(name, mode, parent, value, &fops_u64);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_u64);
+
static ssize_t read_file_bool(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index 9fa0983..5a9c495 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -44,6 +44,8 @@ struct dentry *debugfs_create_u16(const char *name, mode_t mode,
struct dentry *parent, u16 *value);
struct dentry *debugfs_create_u32(const char *name, mode_t mode,
struct dentry *parent, u32 *value);
+struct dentry *debugfs_create_u64(const char *name, mode_t mode,
+ struct dentry *parent, u64 *value);
struct dentry *debugfs_create_bool(const char *name, mode_t mode,
struct dentry *parent, u32 *value);

@@ -104,6 +106,13 @@ static inline struct dentry *debugfs_create_u32(const char *name, mode_t mode,
return ERR_PTR(-ENODEV);
}

+static inline struct dentry *debugfs_create_u64(const char *name, mode_t mode,
+ struct dentry *parent,
+ u64 *value)
+{
+ return ERR_PTR(-ENODEV);
+}
+
static inline struct dentry *debugfs_create_bool(const char *name, mode_t mode,
struct dentry *parent,
u32 *value)
--
1.5.1.2