Unlike sysfs, debugfs is not netns aware. So batman has to take care to avoid namespace clashes.
Each namespace is given a directory within debugfs/batman-adv/netns, using the namespaces inum as the directory name. Files for namespaces other than the global namespace are placed within the namespace specific directory. Additionally, a symbolic link is used to link the global namespaces inum back to debugfs/batman-adv/ so tools do not need to differentiate between the global namespace and other namespaces. Signed-off-by: Andrew Lunn <[email protected]> --- v2: Add missing includes --- net/batman-adv/debugfs.c | 119 +++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 116 insertions(+), 3 deletions(-) diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c index 3dc5208..1c6b71c 100644 --- a/net/batman-adv/debugfs.c +++ b/net/batman-adv/debugfs.c @@ -27,8 +27,12 @@ #include <linux/fs.h> #include <linux/jiffies.h> #include <linux/kernel.h> +#include <linux/kref.h> +#include <linux/list.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/netdevice.h> +#include <linux/ns_common.h> #include <linux/poll.h> #include <linux/printk.h> #include <linux/sched.h> /* for linux/wait.h */ @@ -42,6 +46,7 @@ #include <linux/types.h> #include <linux/uaccess.h> #include <linux/wait.h> +#include <net/net_namespace.h> #include <stdarg.h> #include "bridge_loop_avoidance.h" @@ -53,6 +58,73 @@ #include "translation-table.h" static struct dentry *batadv_debugfs; +static struct dentry *batadv_ns_debugfs; + +struct batadv_debugfs_ns_entry { + struct net *net; + struct dentry *dir; + struct kref refcount; + struct list_head link; +}; + +static LIST_HEAD(batadv_debugfs_ns); +static DEFINE_MUTEX(batadv_debugfs_ns_mutex); + +static struct dentry *batadv_debugfs_ns_get(struct net *net) +{ + struct batadv_debugfs_ns_entry *ns_entry; + char name[32]; + + mutex_lock(&batadv_debugfs_ns_mutex); + list_for_each_entry(ns_entry, &batadv_debugfs_ns, link) { + if (ns_entry->net == net) { + kref_get(&ns_entry->refcount); + mutex_unlock(&batadv_debugfs_ns_mutex); + return ns_entry->dir; + } + } + + ns_entry = kzalloc(sizeof(*ns_entry), GFP_ATOMIC); + if (ns_entry) { + INIT_LIST_HEAD(&ns_entry->link); + ns_entry->net = net; + kref_init(&ns_entry->refcount); + sprintf(name, "%u", net->ns.inum); + ns_entry->dir = debugfs_create_dir(name, batadv_ns_debugfs); + if (!ns_entry->dir) { + kfree(ns_entry); + mutex_unlock(&batadv_debugfs_ns_mutex); + return NULL; + } + list_add(&ns_entry->link, &batadv_debugfs_ns); + } + mutex_unlock(&batadv_debugfs_ns_mutex); + return ns_entry->dir; +} + +static void batadv_ns_entry_release(struct kref *ref) +{ + struct batadv_debugfs_ns_entry *ns_entry; + + ns_entry = container_of(ref, struct batadv_debugfs_ns_entry, refcount); + debugfs_remove_recursive(ns_entry->dir); + list_del(&ns_entry->link); + kfree(ns_entry); +} + +static void batadv_debugfs_ns_put(struct net *net) +{ + struct batadv_debugfs_ns_entry *ns_entry; + + mutex_lock(&batadv_debugfs_ns_mutex); + list_for_each_entry(ns_entry, &batadv_debugfs_ns, link) { + if (ns_entry->net == net) { + kref_put(&ns_entry->refcount, batadv_ns_entry_release); + break; + } + } + mutex_unlock(&batadv_debugfs_ns_mutex); +} #ifdef CONFIG_BATMAN_ADV_DEBUG #define BATADV_LOG_BUFF_MASK (batadv_log_buff_len - 1) @@ -451,6 +523,7 @@ void batadv_debugfs_init(void) { struct batadv_debuginfo **bat_debug; struct dentry *file; + char name[32]; batadv_debugfs = debugfs_create_dir(BATADV_DEBUGFS_SUBDIR, NULL); if (batadv_debugfs == ERR_PTR(-ENODEV)) @@ -471,6 +544,15 @@ void batadv_debugfs_init(void) } } + batadv_ns_debugfs = debugfs_create_dir("netns", batadv_debugfs); + if (!batadv_ns_debugfs) + goto err; + + /* Create a symlink for the default name space */ + sprintf(name, "%u", init_net.ns.inum); + if (!debugfs_create_symlink(name, batadv_ns_debugfs, "..")) + goto err; + return; err: debugfs_remove_recursive(batadv_debugfs); @@ -492,14 +574,24 @@ void batadv_debugfs_destroy(void) */ int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface) { + struct net *net = dev_net(hard_iface->net_dev); + char *name = hard_iface->net_dev->name; struct batadv_debuginfo **bat_debug; + struct dentry *debugfs_ns_dir; struct dentry *file; if (!batadv_debugfs) goto out; - hard_iface->debug_dir = debugfs_create_dir(hard_iface->net_dev->name, - batadv_debugfs); + debugfs_ns_dir = batadv_debugfs; + + if (net != &init_net) { + debugfs_ns_dir = batadv_debugfs_ns_get(net); + if (!debugfs_ns_dir) + goto out; + } + + hard_iface->debug_dir = debugfs_create_dir(name, debugfs_ns_dir); if (!hard_iface->debug_dir) goto out; @@ -517,6 +609,8 @@ int batadv_debugfs_add_hardif(struct batadv_hard_iface *hard_iface) rem_attr: debugfs_remove_recursive(hard_iface->debug_dir); hard_iface->debug_dir = NULL; + if (net != &init_net) + batadv_debugfs_ns_put(net); out: return -ENOMEM; } @@ -528,22 +622,36 @@ out: */ void batadv_debugfs_del_hardif(struct batadv_hard_iface *hard_iface) { + struct net *net = dev_net(hard_iface->net_dev); + if (batadv_debugfs) { debugfs_remove_recursive(hard_iface->debug_dir); hard_iface->debug_dir = NULL; } + if (net != &init_net) + batadv_debugfs_ns_put(net); } int batadv_debugfs_add_meshif(struct net_device *dev) { struct batadv_priv *bat_priv = netdev_priv(dev); struct batadv_debuginfo **bat_debug; + struct net *net = dev_net(dev); + struct dentry *debugfs_ns_dir; struct dentry *file; if (!batadv_debugfs) goto out; - bat_priv->debug_dir = debugfs_create_dir(dev->name, batadv_debugfs); + debugfs_ns_dir = batadv_debugfs; + + if (net != &init_net) { + debugfs_ns_dir = batadv_debugfs_ns_get(net); + if (!debugfs_ns_dir) + goto out; + } + + bat_priv->debug_dir = debugfs_create_dir(dev->name, debugfs_ns_dir); if (!bat_priv->debug_dir) goto out; @@ -572,6 +680,8 @@ int batadv_debugfs_add_meshif(struct net_device *dev) rem_attr: debugfs_remove_recursive(bat_priv->debug_dir); bat_priv->debug_dir = NULL; + if (net != &init_net) + batadv_debugfs_ns_put(net); out: return -ENOMEM; } @@ -579,6 +689,7 @@ out: void batadv_debugfs_del_meshif(struct net_device *dev) { struct batadv_priv *bat_priv = netdev_priv(dev); + struct net *net = dev_net(dev); batadv_debug_log_cleanup(bat_priv); @@ -586,4 +697,6 @@ void batadv_debugfs_del_meshif(struct net_device *dev) debugfs_remove_recursive(bat_priv->debug_dir); bat_priv->debug_dir = NULL; } + if (net != &init_net) + batadv_debugfs_ns_put(net); } -- 2.7.0.rc3
