[PATCH] sample_configfs: bin_file read and write

From: SunKe
Date: Wed Jul 10 2019 - 07:00:08 EST


Add bin_file read and write function

Signed-off-by: SunKe <sunke32@xxxxxxxxxx>
---
samples/configfs/configfs_sample.c | 43 ++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)

diff --git a/samples/configfs/configfs_sample.c b/samples/configfs/configfs_sample.c
index 004a4e2..c76b784 100644
--- a/samples/configfs/configfs_sample.c
+++ b/samples/configfs/configfs_sample.c
@@ -146,6 +146,8 @@ static struct childless childless_subsys = {
struct simple_child {
struct config_item item;
int storeme;
+ void *data;
+ size_t len;
};

static inline struct simple_child *to_simple_child(struct config_item *item)
@@ -153,6 +155,46 @@ static inline struct simple_child *to_simple_child(struct config_item *item)
return item ? container_of(item, struct simple_child, item) : NULL;
}

+static ssize_t simple_child_bin_storeme_bin_write(struct config_item *item,
+ const void *data, size_t size)
+{
+ struct simple_child *simple_child = to_simple_child(item);
+
+ kfree(simple_child->data);
+ simple_child->data = NULL;
+
+ simple_child->data = kmemdup(data, size, GFP_KERNEL);
+ if (!simple_child->data)
+ return -ENOMEM;
+ simple_child->len = size;
+
+ return 0;
+}
+
+static ssize_t simple_child_bin_storeme_bin_read(struct config_item *item,
+ void *data, size_t size)
+{
+ struct simple_child *simple_child = to_simple_child(item);
+
+ if (!data) {
+ size = simple_child->len;
+ } else {
+ memcpy(data, simple_child->data, simple_child->len);
+ size = simple_child->len;
+ }
+
+ return size;
+}
+
+#define MAX_SIZE (128 * 1024)
+
+CONFIGFS_BIN_ATTR(simple_child_bin_, storeme_bin, NULL, MAX_SIZE);
+
+static struct configfs_bin_attribute *simple_child_bin_attrs[] = {
+ &simple_child_bin_attr_storeme_bin,
+ NULL,
+};
+
static ssize_t simple_child_storeme_show(struct config_item *item, char *page)
{
return sprintf(page, "%d\n", to_simple_child(item)->storeme);
@@ -196,6 +238,7 @@ static struct configfs_item_operations simple_child_item_ops = {
static const struct config_item_type simple_child_type = {
.ct_item_ops = &simple_child_item_ops,
.ct_attrs = simple_child_attrs,
+ .ct_bin_attrs = simple_child_bin_attrs,
.ct_owner = THIS_MODULE,
};

--
2.7.4