#include <linux/moduleparam.h>
#include <linux/string.h>
#include <linux/netpoll.h>
+#include <linux/inet.h>
+#include <linux/configfs.h>
MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>");
MODULE_DESCRIPTION("Console driver for network interfaces");
/**
* struct netconsole_target - Represents a configured netconsole target.
* @list: Links this target into the target_list.
+ * @item: Links us into the configfs subsystem hierarchy.
+ * @enabled: On / off knob to enable / disable target.
+ * Visible from userspace (read-write).
+ * We maintain a strict 1:1 correspondence between this and
+ * whether the corresponding netpoll is active or inactive.
+ * Also, other parameters of a target may be modified at
+ * runtime only when it is disabled (enabled == 0).
* @np: The netpoll structure for this target.
+ * Contains the other userspace visible parameters:
+ * dev_name (read-write)
+ * local_port (read-write)
+ * remote_port (read-write)
+ * local_ip (read-write)
+ * remote_ip (read-write)
+ * local_mac (read-only)
+ * remote_mac (read-write)
*/
struct netconsole_target {
struct list_head list;
+#ifdef CONFIG_NETCONSOLE_DYNAMIC
+ struct config_item item;
+#endif
+ int enabled;
struct netpoll np;
};
-/* Allocate new target and setup netpoll for it */
-static struct netconsole_target *alloc_target(char *target_config)
+#ifdef CONFIG_NETCONSOLE_DYNAMIC
+
+static struct configfs_subsystem netconsole_subsys;
+
+static int __init dynamic_netconsole_init(void)
+{
+ config_group_init(&netconsole_subsys.su_group);
+ mutex_init(&netconsole_subsys.su_mutex);
+ return configfs_register_subsystem(&netconsole_subsys);
+}
+
+static void __exit dynamic_netconsole_exit(void)
+{
+ configfs_unregister_subsystem(&netconsole_subsys);
+}
+
+/*
+ * Targets that were created by parsing the boot/module option string
+ * do not exist in the configfs hierarchy (and have NULL names) and will
+ * never go away, so make these a no-op for them.
+ */
+static void netconsole_target_get(struct netconsole_target *nt)
+{
+ if (config_item_name(&nt->item))
+ config_item_get(&nt->item);
+}
+
+static void netconsole_target_put(struct netconsole_target *nt)
+{
+ if (config_item_name(&nt->item))
+ config_item_put(&nt->item);
+}
+
+#else /* !CONFIG_NETCONSOLE_DYNAMIC */
+
+static int __init dynamic_netconsole_init(void)
+{
+ return 0;
+}
+
+static void __exit dynamic_netconsole_exit(void)
+{
+}
+
+/*
+ * No danger of targets going away from under us when dynamic
+ * reconfigurability is off.
+ */
+static void netconsole_target_get(struct netconsole_target *nt)
+{
+}
+
+static void netconsole_target_put(struct netconsole_target *nt)
+{
+}
+
+#endif /* CONFIG_NETCONSOLE_DYNAMIC */
+
+/* Allocate new target (from boot/module param) and setup netpoll for it */
+static struct netconsole_target *alloc_param_target(char *target_config)
{
int err = -ENOMEM;
struct netconsole_target *nt;
- /* Allocate and initialize with defaults */
+ /*
+ * Allocate and initialize with defaults.
+ * Note that these targets get their config_item fields zeroed-out.
+ */
nt = kzalloc(sizeof(*nt), GFP_KERNEL);
if (!nt) {
printk(KERN_ERR "netconsole: failed to allocate memory\n");
if (err)
goto fail;
+ nt->enabled = 1;
+
return nt;
fail:
return ERR_PTR(err);
}
-/* Cleanup netpoll for given target and free it */
-static void free_target(struct netconsole_target *nt)
+/* Cleanup netpoll for given target (from boot/module param) and free it */
+static void free_param_target(struct netconsole_target *nt)
{
netpoll_cleanup(&nt->np);
kfree(nt);
}
+#ifdef CONFIG_NETCONSOLE_DYNAMIC
+
+/*
+ * Our subsystem hierarchy is:
+ *
+ * /sys/kernel/config/netconsole/
+ * |
+ * <target>/
+ * | enabled
+ * | dev_name
+ * | local_port
+ * | remote_port
+ * | local_ip
+ * | remote_ip
+ * | local_mac
+ * | remote_mac
+ * |
+ * <target>/...
+ */
+
+struct netconsole_target_attr {
+ struct configfs_attribute attr;
+ ssize_t (*show)(struct netconsole_target *nt,
+ char *buf);
+ ssize_t (*store)(struct netconsole_target *nt,
+ const char *buf,
+ size_t count);
+};
+
+static struct netconsole_target *to_target(struct config_item *item)
+{
+ return item ?
+ container_of(item, struct netconsole_target, item) :
+ NULL;
+}
+
+/*
+ * Wrapper over simple_strtol (base 10) with sanity and range checking.
+ * We return (signed) long only because we may want to return errors.
+ * Do not use this to convert numbers that are allowed to be negative.
+ */
+static long strtol10_check_range(const char *cp, long min, long max)
+{
+ long ret;
+ char *p = (char *) cp;
+
+ WARN_ON(min < 0);
+ WARN_ON(max < min);
+
+ ret = simple_strtol(p, &p, 10);
+
+ if (*p && (*p != '\n')) {
+ printk(KERN_ERR "netconsole: invalid input\n");
+ return -EINVAL;
+ }
+ if ((ret < min) || (ret > max)) {
+ printk(KERN_ERR "netconsole: input %ld must be between "
+ "%ld and %ld\n", ret, min, max);
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+/*
+ * Attribute operations for netconsole_target.
+ */
+
+static ssize_t show_enabled(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", nt->enabled);
+}
+
+static ssize_t show_dev_name(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%s\n", nt->np.dev_name);
+}
+
+static ssize_t show_local_port(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.local_port);
+}
+
+static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.remote_port);
+}
+
+static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
+ HIPQUAD(nt->np.local_ip));
+}
+
+static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
+ HIPQUAD(nt->np.remote_ip));
+}
+
+static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%02x:%02x:%02x:%02x:%02x:%02x\n",
+ nt->np.local_mac[0], nt->np.local_mac[1],
+ nt->np.local_mac[2], nt->np.local_mac[3],
+ nt->np.local_mac[4], nt->np.local_mac[5]);
+}
+
+static ssize_t show_remote_mac(struct netconsole_target *nt, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%02x:%02x:%02x:%02x:%02x:%02x\n",
+ nt->np.remote_mac[0], nt->np.remote_mac[1],
+ nt->np.remote_mac[2], nt->np.remote_mac[3],
+ nt->np.remote_mac[4], nt->np.remote_mac[5]);
+}
+
+/*
+ * This one is special -- targets created through the configfs interface
+ * are not enabled (and the corresponding netpoll activated) by default.
+ * The user is expected to set the desired parameters first (which
+ * would enable him to dynamically add new netpoll targets for new
+ * network interfaces as and when they come up).
+ */
+static ssize_t store_enabled(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ int err;
+ long enabled;
+
+ enabled = strtol10_check_range(buf, 0, 1);
+ if (enabled < 0)
+ return enabled;
+
+ if (enabled) { /* 1 */
+
+ /*
+ * Skip netpoll_parse_options() -- all the attributes are
+ * already configured via configfs. Just print them out.
+ */
+ netpoll_print_options(&nt->np);
+
+ err = netpoll_setup(&nt->np);
+ if (err)
+ return err;
+
+ printk(KERN_INFO "netconsole: network logging started\n");
+
+ } else { /* 0 */
+ netpoll_cleanup(&nt->np);
+ }
+
+ nt->enabled = enabled;
+
+ return strnlen(buf, count);
+}
+
+static ssize_t store_dev_name(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ size_t len;
+
+ if (nt->enabled) {
+ printk(KERN_ERR "netconsole: target (%s) is enabled, "
+ "disable to update parameters\n",
+ config_item_name(&nt->item));
+ return -EINVAL;
+ }
+
+ strlcpy(nt->np.dev_name, buf, IFNAMSIZ);
+
+ /* Get rid of possible trailing newline from echo(1) */
+ len = strnlen(nt->np.dev_name, IFNAMSIZ);
+ if (nt->np.dev_name[len - 1] == '\n')
+ nt->np.dev_name[len - 1] = '\0';
+
+ return strnlen(buf, count);
+}
+
+static ssize_t store_local_port(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ long local_port;
+#define __U16_MAX ((__u16) ~0U)
+
+ if (nt->enabled) {
+ printk(KERN_ERR "netconsole: target (%s) is enabled, "
+ "disable to update parameters\n",
+ config_item_name(&nt->item));
+ return -EINVAL;
+ }
+
+ local_port = strtol10_check_range(buf, 0, __U16_MAX);
+ if (local_port < 0)
+ return local_port;
+
+ nt->np.local_port = local_port;
+
+ return strnlen(buf, count);
+}
+
+static ssize_t store_remote_port(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ long remote_port;
+#define __U16_MAX ((__u16) ~0U)
+
+ if (nt->enabled) {
+ printk(KERN_ERR "netconsole: target (%s) is enabled, "
+ "disable to update parameters\n",
+ config_item_name(&nt->item));
+ return -EINVAL;
+ }
+
+ remote_port = strtol10_check_range(buf, 0, __U16_MAX);
+ if (remote_port < 0)
+ return remote_port;
+
+ nt->np.remote_port = remote_port;
+
+ return strnlen(buf, count);
+}
+
+static ssize_t store_local_ip(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ if (nt->enabled) {
+ printk(KERN_ERR "netconsole: target (%s) is enabled, "
+ "disable to update parameters\n",
+ config_item_name(&nt->item));
+ return -EINVAL;
+ }
+
+ nt->np.local_ip = ntohl(in_aton(buf));
+
+ return strnlen(buf, count);
+}
+
+static ssize_t store_remote_ip(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ if (nt->enabled) {
+ printk(KERN_ERR "netconsole: target (%s) is enabled, "
+ "disable to update parameters\n",
+ config_item_name(&nt->item));
+ return -EINVAL;
+ }
+
+ nt->np.remote_ip = ntohl(in_aton(buf));
+
+ return strnlen(buf, count);
+}
+
+static ssize_t store_remote_mac(struct netconsole_target *nt,
+ const char *buf,
+ size_t count)
+{
+ u8 remote_mac[ETH_ALEN];
+ char *p = (char *) buf;
+ int i;
+
+ if (nt->enabled) {
+ printk(KERN_ERR "netconsole: target (%s) is enabled, "
+ "disable to update parameters\n",
+ config_item_name(&nt->item));
+ return -EINVAL;
+ }
+
+ for (i = 0; i < ETH_ALEN - 1; i++) {
+ remote_mac[i] = simple_strtoul(p, &p, 16);
+ if (*p != ':')
+ goto invalid;
+ p++;
+ }
+ remote_mac[ETH_ALEN - 1] = simple_strtoul(p, &p, 16);
+ if (*p && (*p != '\n'))
+ goto invalid;
+
+ memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
+
+ return strnlen(buf, count);
+
+invalid:
+ printk(KERN_ERR "netconsole: invalid input\n");
+ return -EINVAL;
+}
+
+/*
+ * Attribute definitions for netconsole_target.
+ */
+
+#define NETCONSOLE_TARGET_ATTR_RO(_name) \
+static struct netconsole_target_attr netconsole_target_##_name = \
+ __CONFIGFS_ATTR(_name, S_IRUGO, show_##_name, NULL)
+
+#define NETCONSOLE_TARGET_ATTR_RW(_name) \
+static struct netconsole_target_attr netconsole_target_##_name = \
+ __CONFIGFS_ATTR(_name, S_IRUGO | S_IWUSR, show_##_name, store_##_name)
+
+NETCONSOLE_TARGET_ATTR_RW(enabled);
+NETCONSOLE_TARGET_ATTR_RW(dev_name);
+NETCONSOLE_TARGET_ATTR_RW(local_port);
+NETCONSOLE_TARGET_ATTR_RW(remote_port);
+NETCONSOLE_TARGET_ATTR_RW(local_ip);
+NETCONSOLE_TARGET_ATTR_RW(remote_ip);
+NETCONSOLE_TARGET_ATTR_RO(local_mac);
+NETCONSOLE_TARGET_ATTR_RW(remote_mac);
+
+static struct configfs_attribute *netconsole_target_attrs[] = {
+ &netconsole_target_enabled.attr,
+ &netconsole_target_dev_name.attr,
+ &netconsole_target_local_port.attr,
+ &netconsole_target_remote_port.attr,
+ &netconsole_target_local_ip.attr,
+ &netconsole_target_remote_ip.attr,
+ &netconsole_target_local_mac.attr,
+ &netconsole_target_remote_mac.attr,
+ NULL,
+};
+
+/*
+ * Item operations and type for netconsole_target.
+ */
+
+static void netconsole_target_release(struct config_item *item)
+{
+ kfree(to_target(item));
+}
+
+static ssize_t netconsole_target_attr_show(struct config_item *item,
+ struct configfs_attribute *attr,
+ char *buf)
+{
+ ssize_t ret = -EINVAL;
+ struct netconsole_target *nt = to_target(item);
+ struct netconsole_target_attr *na =
+ container_of(attr, struct netconsole_target_attr, attr);
+
+ if (na->show)
+ ret = na->show(nt, buf);
+
+ return ret;
+}
+
+static ssize_t netconsole_target_attr_store(struct config_item *item,
+ struct configfs_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ ssize_t ret = -EINVAL;
+ struct netconsole_target *nt = to_target(item);
+ struct netconsole_target_attr *na =
+ container_of(attr, struct netconsole_target_attr, attr);
+
+ if (na->store)
+ ret = na->store(nt, buf, count);
+
+ return ret;
+}
+
+static struct configfs_item_operations netconsole_target_item_ops = {
+ .release = netconsole_target_release,
+ .show_attribute = netconsole_target_attr_show,
+ .store_attribute = netconsole_target_attr_store,
+};
+
+static struct config_item_type netconsole_target_type = {
+ .ct_attrs = netconsole_target_attrs,
+ .ct_item_ops = &netconsole_target_item_ops,
+ .ct_owner = THIS_MODULE,
+};
+
+/*
+ * Group operations and type for netconsole_subsys.
+ */
+
+static struct config_item *make_netconsole_target(struct config_group *group,
+ const char *name)
+{
+ unsigned long flags;
+ struct netconsole_target *nt;
+
+ /*
+ * Allocate and initialize with defaults.
+ * Target is disabled at creation (enabled == 0).
+ */
+ nt = kzalloc(sizeof(*nt), GFP_KERNEL);
+ if (!nt) {
+ printk(KERN_ERR "netconsole: failed to allocate memory\n");
+ return NULL;
+ }
+
+ nt->np.name = "netconsole";
+ strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
+ nt->np.local_port = 6665;
+ nt->np.remote_port = 6666;
+ memset(nt->np.remote_mac, 0xff, ETH_ALEN);
+
+ /* Initialize the config_item member */
+ config_item_init_type_name(&nt->item, name, &netconsole_target_type);
+
+ /* Adding, but it is disabled */
+ spin_lock_irqsave(&target_list_lock, flags);
+ list_add(&nt->list, &target_list);
+ spin_unlock_irqrestore(&target_list_lock, flags);
+
+ return &nt->item;
+}
+
+static void drop_netconsole_target(struct config_group *group,
+ struct config_item *item)
+{
+ unsigned long flags;
+ struct netconsole_target *nt = to_target(item);
+
+ spin_lock_irqsave(&target_list_lock, flags);
+ list_del(&nt->list);
+ spin_unlock_irqrestore(&target_list_lock, flags);
+
+ /*
+ * The target may have never been enabled, or was manually disabled
+ * before being removed so netpoll may have already been cleaned up.
+ */
+ if (nt->enabled)
+ netpoll_cleanup(&nt->np);
+
+ config_item_put(&nt->item);
+}
+
+static struct configfs_group_operations netconsole_subsys_group_ops = {
+ .make_item = make_netconsole_target,
+ .drop_item = drop_netconsole_target,
+};
+
+static struct config_item_type netconsole_subsys_type = {
+ .ct_group_ops = &netconsole_subsys_group_ops,
+ .ct_owner = THIS_MODULE,
+};
+
+/* The netconsole configfs subsystem */
+static struct configfs_subsystem netconsole_subsys = {
+ .su_group = {
+ .cg_item = {
+ .ci_namebuf = "netconsole",
+ .ci_type = &netconsole_subsys_type,
+ },
+ },
+};
+
+#endif /* CONFIG_NETCONSOLE_DYNAMIC */
+
/* Handle network interface device notifications */
static int netconsole_netdev_event(struct notifier_block *this,
unsigned long event,
spin_lock_irqsave(&target_list_lock, flags);
list_for_each_entry(nt, &target_list, list) {
+ netconsole_target_get(nt);
if (nt->np.dev == dev) {
switch (event) {
case NETDEV_CHANGEADDR:
break;
}
}
+ netconsole_target_put(nt);
}
spin_unlock_irqrestore(&target_list_lock, flags);
spin_lock_irqsave(&target_list_lock, flags);
list_for_each_entry(nt, &target_list, list) {
- if (netif_running(nt->np.dev)) {
+ netconsole_target_get(nt);
+ if (nt->enabled && netif_running(nt->np.dev)) {
/*
* We nest this inside the for-each-target loop above
* so that we're able to get as much logging out to
left -= frag;
}
}
+ netconsole_target_put(nt);
}
spin_unlock_irqrestore(&target_list_lock, flags);
}
static int __init init_netconsole(void)
{
- int err = 0;
+ int err;
struct netconsole_target *nt, *tmp;
unsigned long flags;
char *target_config;
char *input = config;
- if (!strnlen(input, MAX_PARAM_LENGTH)) {
- printk(KERN_INFO "netconsole: not configured, aborting\n");
- goto out;
- }
-
- while ((target_config = strsep(&input, ";"))) {
- nt = alloc_target(target_config);
- if (IS_ERR(nt)) {
- err = PTR_ERR(nt);
- goto fail;
+ if (strnlen(input, MAX_PARAM_LENGTH)) {
+ while ((target_config = strsep(&input, ";"))) {
+ nt = alloc_param_target(target_config);
+ if (IS_ERR(nt)) {
+ err = PTR_ERR(nt);
+ goto fail;
+ }
+ spin_lock_irqsave(&target_list_lock, flags);
+ list_add(&nt->list, &target_list);
+ spin_unlock_irqrestore(&target_list_lock, flags);
}
- spin_lock_irqsave(&target_list_lock, flags);
- list_add(&nt->list, &target_list);
- spin_unlock_irqrestore(&target_list_lock, flags);
}
err = register_netdevice_notifier(&netconsole_netdev_notifier);
if (err)
goto fail;
+ err = dynamic_netconsole_init();
+ if (err)
+ goto undonotifier;
+
register_console(&netconsole);
printk(KERN_INFO "netconsole: network logging started\n");
-out:
return err;
+undonotifier:
+ unregister_netdevice_notifier(&netconsole_netdev_notifier);
+
fail:
printk(KERN_ERR "netconsole: cleaning up\n");
/*
- * Remove all targets and destroy them. Skipping the list
+ * Remove all targets and destroy them (only targets created
+ * from the boot/module option exist here). Skipping the list
* lock is safe here, and netpoll_cleanup() will sleep.
*/
list_for_each_entry_safe(nt, tmp, &target_list, list) {
list_del(&nt->list);
- free_target(nt);
+ free_param_target(nt);
}
return err;
struct netconsole_target *nt, *tmp;
unregister_console(&netconsole);
+ dynamic_netconsole_exit();
unregister_netdevice_notifier(&netconsole_netdev_notifier);
/*
- * Remove all targets and destroy them. Skipping the list
- * lock is safe here, and netpoll_cleanup() will sleep.
+ * Targets created via configfs pin references on our module
+ * and would first be rmdir(2)'ed from userspace. We reach
+ * here only when they are already destroyed, and only those
+ * created from the boot/module option are left, so remove and
+ * destroy them. Skipping the list lock is safe here, and
+ * netpoll_cleanup() will sleep.
*/
list_for_each_entry_safe(nt, tmp, &target_list, list) {
list_del(&nt->list);
- free_target(nt);
+ free_param_target(nt);
}
}
projects / linux-2.6 / commitdiff