[KERNEL] SysFS interface added (/sys/block/dnbd*/net/)

1 files changed, 212 insertions, 0 deletions

diff --git a/src/kernel/sysfs.c b/src/kernel/sysfs.c
new file mode 100644
index 0000000..e363824
--- /dev/null
+++ b/src/kernel/sysfs.c
@@ -0,0 +1,212 @@
+/*
+ * This file is part of the Distributed Network Block Device 3
+ *
+ * Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
+ *
+ * This file may be licensed under the terms of of the
+ * GNU General Public License Version 2 (the ``GPL'').
+ *
+ * Software distributed under the License is distributed
+ * on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
+ * express or implied. See the GPL for the specific language
+ * governing rights and limitations.
+ *
+ * You should have received a copy of the GPL along with this
+ * program. If not, go to http://www.gnu.org/licenses/gpl.html
+ * or write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include <linux/kobject.h>
+
+#include "sysfs.h"
+#include "utils.h"
+
+typedef struct
+{
+    struct attribute attr;
+    ssize_t (*show)(char *, dnbd3_device_t *);
+    ssize_t (*store)(const char *, size_t, dnbd3_device_t *);
+} device_attr_t;
+
+typedef struct
+{
+    struct attribute attr;
+    ssize_t (*show)(char *, dnbd3_server_t *);
+    ssize_t (*store)(const char *, size_t, dnbd3_server_t *);
+} server_attr_t;
+
+
+ssize_t show_cur_server_ip(char *buf, dnbd3_device_t *dev)
+{
+    return sprintf(buf, "%s\n", dev->cur_server.host);
+}
+
+ssize_t show_cur_server_rtt(char *buf, dnbd3_device_t *dev)
+{
+    return sprintf(buf, "%lluus\n", dev->cur_server.rtt);
+}
+
+ssize_t show_alt_server_num(char *buf, dnbd3_device_t *dev)
+{
+    return sprintf(buf, "%d\n", dev->alt_servers_num);
+}
+
+ssize_t show_vid(char *buf, dnbd3_device_t *dev)
+{
+    return sprintf(buf, "%d\n", dev->vid);
+}
+
+ssize_t show_rid(char *buf, dnbd3_device_t *dev)
+{
+    return sprintf(buf, "%d\n", dev->rid);
+}
+
+ssize_t show_alt_server_ip(char *buf, dnbd3_server_t *srv)
+{
+    return sprintf(buf, "%s\n", srv->host);
+}
+
+ssize_t show_alt_server_rtt(char *buf, dnbd3_server_t *srv)
+{
+    return sprintf(buf, "%lluus\n", srv->rtt);
+}
+
+device_attr_t cur_server_ip =
+{
+    .attr = {.name = "cur_server_ip", .mode = 0444 },
+    .show   = show_cur_server_ip,
+    .store  = NULL,
+};
+
+device_attr_t cur_server_rtt =
+{
+    .attr = {.name = "cur_server_rtt", .mode = 0444 },
+    .show   = show_cur_server_rtt,
+    .store  = NULL,
+};
+
+device_attr_t alt_server_num =
+{
+    .attr = {.name = "alt_server_num", .mode = 0444 },
+    .show   = show_alt_server_num,
+    .store  = NULL,
+};
+
+device_attr_t vid =
+{
+    .attr = {.name = "vid", .mode = 0444 },
+    .show   = show_vid,
+    .store  = NULL,
+};
+
+device_attr_t rid =
+{
+    .attr = {.name = "rid", .mode = 0444 },
+    .show   = show_rid,
+    .store  = NULL,
+};
+
+server_attr_t alt_server_ip =
+{
+    .attr = {.name = "alt_server_ip", .mode = 0444 },
+    .show   = show_alt_server_ip,
+    .store  = NULL,
+};
+
+server_attr_t alt_server_rtt =
+{
+    .attr = {.name = "alt_server_rtt", .mode = 0444 },
+    .show   = show_alt_server_rtt,
+    .store  = NULL,
+};
+
+ssize_t device_show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+    device_attr_t *device_attr = container_of(attr, device_attr_t, attr);
+    dnbd3_device_t *dev = container_of(kobj, dnbd3_device_t, kobj);
+    return device_attr->show(buf, dev);
+}
+
+ssize_t server_show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+    server_attr_t *server_attr = container_of(attr, server_attr_t, attr);
+    dnbd3_server_t *srv = container_of(kobj, dnbd3_server_t, kobj);
+    return server_attr->show(buf, srv);
+}
+
+struct attribute *device_attrs[] =
+{
+    &cur_server_ip.attr,
+    &cur_server_rtt.attr,
+    &alt_server_num.attr,
+    &vid.attr,
+    &rid.attr,
+    NULL,
+};
+
+struct attribute *server_attrs[] =
+{
+    &alt_server_ip.attr,
+    &alt_server_rtt.attr,
+    NULL,
+};
+
+struct sysfs_ops device_ops =
+{
+    .show = device_show,
+};
+
+struct sysfs_ops server_ops =
+{
+    .show = server_show,
+};
+
+void release(struct kobject *kobj) {}
+
+struct kobj_type device_ktype =
+{
+    .default_attrs = device_attrs,
+    .sysfs_ops = &device_ops,
+    .release = release,
+};
+
+struct kobj_type server_ktype =
+{
+    .default_attrs = server_attrs,
+    .sysfs_ops = &server_ops,
+    .release = release,
+};
+
+void dnbd3_sysfs_init(dnbd3_device_t *dev)
+{
+    int i;
+    char name[] = "alt_server99";
+    struct kobject *kobj = &dev->kobj;
+    struct kobj_type *ktype = &device_ktype;
+    struct kobject *parent = &disk_to_dev(dev->disk)->kobj;
+
+    kobject_init_and_add(kobj, ktype, parent, "net");
+
+    for (i = 0; i < NUMBER_SERVERS; i++)
+    {
+        sprintf(name, "alt_server%d", i);
+        kobj = &dev->alt_servers[i].kobj;
+        ktype = &server_ktype;
+        parent = &dev->kobj;
+        kobject_init_and_add(kobj, ktype, parent, name);
+    }
+}
+
+void dnbd3_sysfs_exit(dnbd3_device_t *dev)
+{
+    int i;
+
+    for (i = 0; i < NUMBER_SERVERS; i++)
+    {
+        kobject_put(&dev->alt_servers[i].kobj);
+    }
+
+    kobject_put(&dev->kobj);
+}