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path: root/drivers/net/netconsole.c
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Diffstat (limited to 'drivers/net/netconsole.c')
-rw-r--r--drivers/net/netconsole.c171
1 files changed, 131 insertions, 40 deletions
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 55570988250..458c4d674a9 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -62,44 +62,93 @@ static int __init option_setup(char *opt)
__setup("netconsole=", option_setup);
#endif /* MODULE */
+/* Linked list of all configured targets */
+static LIST_HEAD(target_list);
+
+/* This needs to be a spinlock because write_msg() cannot sleep */
+static DEFINE_SPINLOCK(target_list_lock);
+
/**
* struct netconsole_target - Represents a configured netconsole target.
+ * @list: Links this target into the target_list.
* @np: The netpoll structure for this target.
*/
struct netconsole_target {
+ struct list_head list;
struct netpoll np;
};
-static struct netconsole_target default_target = {
- .np = {
- .name = "netconsole",
- .dev_name = "eth0",
- .local_port = 6665,
- .remote_port = 6666,
- .remote_mac = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
- },
-};
+/* Allocate new target and setup netpoll for it */
+static struct netconsole_target *alloc_target(char *target_config)
+{
+ int err = -ENOMEM;
+ struct netconsole_target *nt;
+
+ /* Allocate and initialize with defaults */
+ nt = kzalloc(sizeof(*nt), GFP_KERNEL);
+ if (!nt) {
+ printk(KERN_ERR "netconsole: failed to allocate memory\n");
+ goto fail;
+ }
+
+ 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);
+
+ /* Parse parameters and setup netpoll */
+ err = netpoll_parse_options(&nt->np, target_config);
+ if (err)
+ goto fail;
+
+ err = netpoll_setup(&nt->np);
+ if (err)
+ goto fail;
+
+ return nt;
+
+fail:
+ kfree(nt);
+ return ERR_PTR(err);
+}
+
+/* Cleanup netpoll for given target and free it */
+static void free_target(struct netconsole_target *nt)
+{
+ netpoll_cleanup(&nt->np);
+ kfree(nt);
+}
/* Handle network interface device notifications */
static int netconsole_netdev_event(struct notifier_block *this,
unsigned long event,
void *ptr)
{
+ unsigned long flags;
+ struct netconsole_target *nt;
struct net_device *dev = ptr;
- struct netconsole_target *nt = &default_target;
- if (nt->np.dev == dev) {
- switch (event) {
- case NETDEV_CHANGEADDR:
- memcpy(nt->np.local_mac, dev->dev_addr, ETH_ALEN);
- break;
+ if (!(event == NETDEV_CHANGEADDR || event == NETDEV_CHANGENAME))
+ goto done;
+
+ spin_lock_irqsave(&target_list_lock, flags);
+ list_for_each_entry(nt, &target_list, list) {
+ if (nt->np.dev == dev) {
+ switch (event) {
+ case NETDEV_CHANGEADDR:
+ memcpy(nt->np.local_mac, dev->dev_addr, ETH_ALEN);
+ break;
- case NETDEV_CHANGENAME:
- strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
- break;
+ case NETDEV_CHANGENAME:
+ strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
+ break;
+ }
}
}
+ spin_unlock_irqrestore(&target_list_lock, flags);
+done:
return NOTIFY_DONE;
}
@@ -111,18 +160,32 @@ static void write_msg(struct console *con, const char *msg, unsigned int len)
{
int frag, left;
unsigned long flags;
- struct netconsole_target *nt = &default_target;
-
- if (netif_running(nt->np.dev)) {
- local_irq_save(flags);
- for (left = len; left;) {
- frag = min(left, MAX_PRINT_CHUNK);
- netpoll_send_udp(&nt->np, msg, frag);
- msg += frag;
- left -= frag;
+ struct netconsole_target *nt;
+ const char *tmp;
+
+ /* Avoid taking lock and disabling interrupts unnecessarily */
+ if (list_empty(&target_list))
+ return;
+
+ spin_lock_irqsave(&target_list_lock, flags);
+ list_for_each_entry(nt, &target_list, list) {
+ if (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
+ * at least one target if we die inside here, instead
+ * of unnecessarily keeping all targets in lock-step.
+ */
+ tmp = msg;
+ for (left = len; left;) {
+ frag = min(left, MAX_PRINT_CHUNK);
+ netpoll_send_udp(&nt->np, tmp, frag);
+ tmp += frag;
+ left -= frag;
+ }
}
- local_irq_restore(flags);
}
+ spin_unlock_irqrestore(&target_list_lock, flags);
}
static struct console netconsole = {
@@ -134,39 +197,67 @@ static struct console netconsole = {
static int __init init_netconsole(void)
{
int err = 0;
- struct netconsole_target *nt = &default_target;
+ struct netconsole_target *nt, *tmp;
+ unsigned long flags;
+ char *target_config;
+ char *input = config;
- if (!strnlen(config, MAX_PARAM_LENGTH)) {
+ if (!strnlen(input, MAX_PARAM_LENGTH)) {
printk(KERN_INFO "netconsole: not configured, aborting\n");
goto out;
}
- err = netpoll_parse_options(&nt->np, config);
- if (err)
- goto out;
-
- err = netpoll_setup(&nt->np);
- if (err)
- goto out;
+ while ((target_config = strsep(&input, ";"))) {
+ nt = alloc_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);
+ }
err = register_netdevice_notifier(&netconsole_netdev_notifier);
if (err)
- goto out;
+ goto fail;
register_console(&netconsole);
printk(KERN_INFO "netconsole: network logging started\n");
out:
return err;
+
+fail:
+ printk(KERN_ERR "netconsole: cleaning up\n");
+
+ /*
+ * Remove all targets 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);
+ }
+
+ return err;
}
static void __exit cleanup_netconsole(void)
{
- struct netconsole_target *nt = &default_target;
+ struct netconsole_target *nt, *tmp;
unregister_console(&netconsole);
unregister_netdevice_notifier(&netconsole_netdev_notifier);
- netpoll_cleanup(&nt->np);
+
+ /*
+ * Remove all targets 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);
+ }
}
module_init(init_netconsole);