[PATCH V2] debugfs: Add debugfs_create_ulong()

Viresh Kumar
2015-10-09T17:11:27Z

Add debugfs_create_ulong() for the users of type 'unsigned long'. These
will be 32 bits long on a 32 bit machine and 64 bits long on a 64 bit
machine.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
V1->V2:
- Fix missing debugfs_create_xlong() routine, was left in the
repository.

fs/debugfs/file.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/debugfs.h | 4 +++
2 files changed, 76 insertions(+)

diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index b70c20fae502..129d19b72fd4 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -251,6 +251,60 @@ struct dentry *debugfs_create_u64(const char *name, umode_t mode,
}
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)
+{
+ /* if there are no write bits set, make read only */
+ if (!(mode & S_IWUGO))
+ return debugfs_create_file(name, mode, parent, value, &fops_ulong_ro);
+ /* if there are no read bits set, make write only */
+ if (!(mode & S_IRUGO))
+ return debugfs_create_file(name, mode, parent, value, &fops_ulong_wo);
+
+ return debugfs_create_file(name, mode, parent, value, &fops_ulong);
+}
+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");
@@ -264,6 +318,7 @@ 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_xlong, debugfs_ulong_get, debugfs_ulong_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
@@ -362,6 +417,23 @@ struct dentry *debugfs_create_x64(const char *name, umode_t mode,
}
EXPORT_SYMBOL_GPL(debugfs_create_x64);

+/**
+ * debugfs_create_xlong - 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.
+ */
+struct dentry *debugfs_create_xlong(const char *name, umode_t mode,
+ struct dentry *parent, unsigned long *value)
+{
+ return debugfs_create_file(name, mode, parent, value, &fops_xlong);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_xlong);
+

static int debugfs_size_t_set(void *data, u64 val)
{
diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index 8321fe3058d6..60b150248b54 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -79,6 +79,8 @@ struct dentry *debugfs_create_u32(const char *name, umode_t mode,
struct dentry *parent, u32 *value);
struct dentry *debugfs_create_u64(const char *name, umode_t mode,
struct dentry *parent, u64 *value);
+struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
+ struct dentry *parent, unsigned long *value);
struct dentry *debugfs_create_x8(const char *name, umode_t mode,
struct dentry *parent, u8 *value);
struct dentry *debugfs_create_x16(const char *name, umode_t mode,
@@ -87,6 +89,8 @@ struct dentry *debugfs_create_x32(const char *name, umode_t mode,
struct dentry *parent, u32 *value);
struct dentry *debugfs_create_x64(const char *name, umode_t mode,
struct dentry *parent, u64 *value);
+struct dentry *debugfs_create_xlong(const char *name, umode_t mode,
+ struct dentry *parent, unsigned long *value);
struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
struct dentry *parent, size_t *value);
struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
--
2.4.0