From: Keiichi KII <[email protected]>
The netconsole is a very useful module for collecting kernel message under
certain circumstances(e.g. disk logging fails, serial port is unavailable).
But current netconsole is not flexible. For example, if you want to change ip
address for logging agent, in the case of built-in netconsole, you can't change
config except for changing boot parameter and rebooting your system, or in the
case of module netconsole, you need to remove it and reload with different
parameters.
So, I propose the following extended features for netconsole.
1) support for multiple logging agents.
2) add interface to access each parameter of netconsole
using sysfs.
This patch is for linux-2.6.20-rc1-mm1 and is divided to each function.
Your comments are very welcome.
Signed-off-by: Keiichi KII <[email protected]>
Signed-off-by: Takayoshi Kochi <[email protected]>
---
--
Keiichi KII
NEC Corporation OSS Promotion Center
E-mail: [email protected]
From: Keiichi KII <[email protected]>
This patch contains the following cleanups.
- add __init for initialization functions(option_setup() and
init_netconsole()).
Signed-off-by: Keiichi KII <[email protected]>
Signed-off-by: Takayoshi Kochi <[email protected]>
---
--- linux-mm/drivers/net/netconsole.c 2006-12-26 14:10:17.177090000 +0900
+++ enhanced-netconsole/drivers/net/netconsole.c.cleanup 2006-12-25 16:44:31.615793750 +0900
@@ -91,7 +91,7 @@ static struct console netconsole = {
.write = write_msg
};
-static int option_setup(char *opt)
+static int __init option_setup(char *opt)
{
configured = !netpoll_parse_options(&np, opt);
return 1;
@@ -99,7 +99,7 @@ static int option_setup(char *opt)
__setup("netconsole=", option_setup);
-static int init_netconsole(void)
+static int __init init_netconsole(void)
{
int err;
--
Keiichi KII
NEC Corporation OSS Promotion Center
E-mail: [email protected]
From: Keiichi KII <[email protected]>
This patch contains the following changes.
create a sysfs entry for netconsole in /sys/class/misc.
This entry has elements related to netconsole as follows.
You can change configuration of netconsole(writable attributes such as IP
address, port number and so on) and check current configuration of netconsole.
-+- /sys/class/misc/
|-+- netconsole/
|-+- port1/
| |--- id [r--r--r--] unique port id
| |--- remove [-w-------] if you write something to "remove",
| | this port is removed.
| |--- dev_name [r--r--r--] network interface name
| |--- local_ip [rw-r--r--] source IP to use, writable
| |--- local_port [rw-r--r--] source port number for UDP packets, writable
| |--- local_mac [r--r--r--] source MAC address
| |--- remote_ip [rw-r--r--] port number for logging agent, writable
| |--- remote_port [rw-r--r--] IP address for logging agent, writable
| ---- remote_mac [rw-r--r--] MAC address for logging agent, writable
|--- port2/
|--- port3/
...
Signed-off-by: Keiichi KII <[email protected]>
Signed-off-by: Takayoshi Kochi <[email protected]>
---
[changes]
1. use ETH_ALEN from if_ether.h.
2. remove initialization for static variable.
3. follow the kernel coding style.
--- linux-mm/drivers/net/netconsole.c 2006-12-26 14:19:01.441854500 +0900
+++ enhanced-netconsole/drivers/net/netconsole.c.sysfs 2006-12-25 16:44:49.520912750 +0900
@@ -45,6 +45,8 @@
#include <linux/sysrq.h>
#include <linux/smp.h>
#include <linux/netpoll.h>
+#include <linux/miscdevice.h>
+#include <linux/inet.h>
MODULE_AUTHOR("Maintainer: Matt Mackall <[email protected]>");
MODULE_DESCRIPTION("Console driver for network interfaces");
@@ -56,18 +58,231 @@ MODULE_PARM_DESC(netconsole, " netconsol
struct netconsole_target {
struct list_head list;
+ struct kobject obj;
int id;
struct netpoll np;
};
+#define MAX_PRINT_CHUNK 1000
+#define CONFIG_SEPARATOR ";"
+
+struct target_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct netconsole_target*, char*);
+ ssize_t (*store)(struct netconsole_target*, const char*,
+ size_t count);
+};
+
static int add_target(char* target_config);
+static void setup_target_sysfs(struct netconsole_target *nt);
static void cleanup_netconsole(void);
static void delete_target(struct netconsole_target *nt);
+static int miscdev_configured;
+
static LIST_HEAD(target_list);
static DEFINE_SPINLOCK(target_list_lock);
+static ssize_t show_id(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%d\n", nt->id);
+}
+
+static ssize_t show_dev_name(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%s\n", nt->np.dev_name);
+}
+
+static ssize_t show_local_port(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%d\n", nt->np.local_port);
+}
+
+static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%d\n", nt->np.remote_port);
+}
+
+static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%d.%d.%d.%d\n", HIPQUAD(nt->np.local_ip));
+}
+
+static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%d.%d.%d.%d\n", HIPQUAD(nt->np.remote_ip));
+}
+
+static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%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 sprintf(buf, "%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]);
+}
+
+static ssize_t store_local_port(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ spin_lock(&target_list_lock);
+ nt->np.local_port = simple_strtol(buf, NULL, 10);
+ spin_unlock(&target_list_lock);
+
+ return count;
+}
+
+static ssize_t store_remote_port(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ spin_lock(&target_list_lock);
+ nt->np.remote_port = simple_strtol(buf, NULL, 10);
+ spin_unlock(&target_list_lock);
+
+ return count;
+}
+
+static ssize_t store_local_ip(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ spin_lock(&target_list_lock);
+ nt->np.local_ip = ntohl(in_aton(buf));
+ spin_unlock(&target_list_lock);
+
+ return count;
+}
+
+static ssize_t store_remote_ip(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ spin_lock(&target_list_lock);
+ nt->np.remote_ip = ntohl(in_aton(buf));
+ spin_unlock(&target_list_lock);
+
+ return count;
+}
+
+static ssize_t store_remote_mac(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ unsigned char input_mac[ETH_ALEN] =
+ {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+ const char *cur = buf;
+ char *delim;
+ int i = 0;
+
+ for(i = 0; i < ETH_ALEN; i++) {
+ input_mac[i] = simple_strtol(cur, NULL, 16);
+ if (i != ETH_ALEN - 1 && (delim = strchr(cur, ':')) == NULL)
+ return -EINVAL;
+ cur = delim + 1;
+ }
+ spin_lock(&target_list_lock);
+ memcpy(nt->np.remote_mac, input_mac, ETH_ALEN);
+ spin_unlock(&target_list_lock);
+
+ return count;
+}
+
+static ssize_t store_remove(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ kobject_unregister(&nt->obj);
+ return count;
+}
+
+#define NETCON_CLASS_ATTR(_name, _mode, _show, _store) \
+struct target_attr target_attr_##_name = \
+ __ATTR(_name, _mode, _show, _store)
+
+static NETCON_CLASS_ATTR(id, S_IRUGO, show_id, NULL);
+static NETCON_CLASS_ATTR(dev_name, S_IRUGO, show_dev_name, NULL);
+static NETCON_CLASS_ATTR(local_port, S_IRUGO | S_IWUSR,
+ show_local_port, store_local_port);
+static NETCON_CLASS_ATTR(remote_port, S_IRUGO | S_IWUSR,
+ show_remote_port, store_remote_port);
+static NETCON_CLASS_ATTR(local_ip, S_IRUGO | S_IWUSR,
+ show_local_ip, store_local_ip);
+static NETCON_CLASS_ATTR(remote_ip, S_IRUGO | S_IWUSR,
+ show_remote_ip, store_remote_ip);
+static NETCON_CLASS_ATTR(local_mac, S_IRUGO, show_local_mac, NULL);
+static NETCON_CLASS_ATTR(remote_mac, S_IRUGO | S_IWUSR,
+ show_remote_mac, store_remote_mac);
+static NETCON_CLASS_ATTR(remove, S_IWUSR, NULL, store_remove);
+
+static struct attribute *target_attrs[] = {
+ &target_attr_id.attr,
+ &target_attr_dev_name.attr,
+ &target_attr_local_port.attr,
+ &target_attr_remote_port.attr,
+ &target_attr_local_ip.attr,
+ &target_attr_remote_ip.attr,
+ &target_attr_local_mac.attr,
+ &target_attr_remote_mac.attr,
+ &target_attr_remove.attr,
+ NULL
+};
+
+static ssize_t show_target_attr(struct kobject *kobj,
+ struct attribute *attr,
+ char *buffer)
+{
+ struct target_attr *na =
+ container_of(attr, struct target_attr, attr);
+ struct netconsole_target * nt =
+ container_of(kobj, struct netconsole_target, obj);
+ if (na->show)
+ return na->show(nt, buffer);
+ else
+ return -EACCES;
+}
+
+static ssize_t store_target_attr(struct kobject *kobj,
+ struct attribute *attr,
+ const char *buffer, size_t count)
+{
+ struct target_attr *na =
+ container_of(attr, struct target_attr, attr);
+ struct netconsole_target *nt =
+ container_of(kobj, struct netconsole_target, obj);
+ if (na->store)
+ return na->store(nt, buffer, count);
+ else
+ return -EACCES;
+}
+
+static void release_target(struct kobject *kobj)
+{
+ struct netconsole_target *nt =
+ container_of(kobj, struct netconsole_target, obj);
+
+ delete_target(nt);
+}
+
+static struct sysfs_ops target_sysfs_ops = {
+ .show = show_target_attr,
+ .store = store_target_attr
+};
+
+static struct kobj_type target_ktype = {
+ .release = release_target,
+ .sysfs_ops = &target_sysfs_ops,
+ .default_attrs = target_attrs,
+};
+
+static struct miscdevice netconsole_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "netconsole",
+};
+
static struct netpoll np = {
.name = "netconsole",
.dev_name = "eth0",
@@ -76,9 +291,6 @@ static struct netpoll np = {
.remote_mac = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
};
-#define MAX_PRINT_CHUNK 1000
-#define CONFIG_SEPARATOR ";"
-
static int add_target(char* target_config)
{
int retval = 0;
@@ -119,10 +331,19 @@ static int add_target(char* target_confi
list_add(&new_target->list, &target_list);
spin_unlock(&target_list_lock);
+ setup_target_sysfs(new_target);
out:
return retval;
}
+static void setup_target_sysfs(struct netconsole_target *nt)
+{
+ kobject_set_name(&nt->obj, "port%d", nt->id);
+ nt->obj.parent = &netconsole_miscdev.class->kobj;
+ nt->obj.ktype = &target_ktype;
+ kobject_register(&nt->obj);
+}
+
static void delete_target(struct netconsole_target *nt)
{
spin_lock(&target_list_lock);
@@ -178,6 +399,15 @@ static int __init init_netconsole(void)
char *p;
char *tmp = config;
+ if (misc_register(&netconsole_miscdev)) {
+ printk(KERN_ERR
+ "netconsole: failed to register misc device for "
+ "name = %s, id = %d\n",
+ netconsole_miscdev.name, netconsole_miscdev.minor);
+ return -EIO;
+ } else
+ miscdev_configured = 1;
+
register_console(&netconsole);
if(!strlen(config)) {
@@ -202,9 +432,13 @@ static void cleanup_netconsole(void)
struct netconsole_target *nt, *tmp;
unregister_console(&netconsole);
+
list_for_each_entry_safe(nt, tmp, &target_list, list) {
- delete_target(nt);
+ kobject_unregister(&nt->obj);
}
+
+ if (miscdev_configured)
+ misc_deregister(&netconsole_miscdev);
}
module_init(init_netconsole);
--
Keiichi KII
NEC Corporation OSS Promotion Center
E-mail: [email protected]
From: Keiichi KII <[email protected]>
This patch contains switch function of netpoll.
If "enabled" attribute of certain port is '1', this port is used
and the configurations of this port are uable to change.
If "enabled" attribute of certain port is '0', this port isn't used
and the configurations of this port are able to change.
-+- /sys/class/misc/
|-+- netconsole/
|-+- port1/
| |--- id [r--r--r--] id
| |--- enabled [rw-r--r--] 0: disable 1: enable, writable
| ...
|--- port2/
...
Signed-off-by: Keiichi KII <[email protected]>
Signed-off-by: Takayoshi Kochi <[email protected]>
---
--- linux-mm/drivers/net/netconsole.c 2006-12-26 14:19:01.461855750 +0900
+++ enhanced-netconsole/drivers/net/netconsole.c.switch 2006-12-25 16:44:57.453408500 +0900
@@ -60,6 +60,7 @@ struct netconsole_target {
struct list_head list;
struct kobject obj;
int id;
+ int enabled;
struct netpoll np;
};
@@ -130,10 +131,19 @@ static ssize_t show_remote_mac(struct ne
nt->np.remote_mac[4], nt->np.remote_mac[5]);
}
+static ssize_t show_enabled(struct netconsole_target *nt, char *buf)
+{
+ return sprintf(buf, "%d\n", nt->enabled);
+}
+
static ssize_t store_local_port(struct netconsole_target *nt, const char *buf,
size_t count)
{
spin_lock(&target_list_lock);
+ if (nt->enabled) {
+ spin_unlock(&target_list_lock);
+ return -EINVAL;
+ }
nt->np.local_port = simple_strtol(buf, NULL, 10);
spin_unlock(&target_list_lock);
@@ -144,6 +154,10 @@ static ssize_t store_remote_port(struct
size_t count)
{
spin_lock(&target_list_lock);
+ if (nt->enabled) {
+ spin_unlock(&target_list_lock);
+ return -EINVAL;
+ }
nt->np.remote_port = simple_strtol(buf, NULL, 10);
spin_unlock(&target_list_lock);
@@ -154,6 +168,10 @@ static ssize_t store_local_ip(struct net
size_t count)
{
spin_lock(&target_list_lock);
+ if (nt->enabled) {
+ spin_unlock(&target_list_lock);
+ return -EINVAL;
+ }
nt->np.local_ip = ntohl(in_aton(buf));
spin_unlock(&target_list_lock);
@@ -164,6 +182,10 @@ static ssize_t store_remote_ip(struct ne
size_t count)
{
spin_lock(&target_list_lock);
+ if (nt->enabled) {
+ spin_unlock(&target_list_lock);
+ return -EINVAL;
+ }
nt->np.remote_ip = ntohl(in_aton(buf));
spin_unlock(&target_list_lock);
@@ -186,12 +208,39 @@ static ssize_t store_remote_mac(struct n
cur = delim + 1;
}
spin_lock(&target_list_lock);
+ if (nt->enabled) {
+ spin_unlock(&target_list_lock);
+ return -EINVAL;
+ }
memcpy(nt->np.remote_mac, input_mac, ETH_ALEN);
spin_unlock(&target_list_lock);
return count;
}
+static ssize_t store_enabled(struct netconsole_target *nt, const char *buf,
+ size_t count)
+{
+ int enabled = 0;
+
+ if (count >= 2 && (count != 2 || buf[count - 1] != '\n')) {
+ printk(KERN_ERR "netconsole: invalid argument: %s\n", buf);
+ return -EINVAL;
+ } else if (strncmp(buf, "1", 1) == 0) {
+ enabled = 1;
+ } else if(strncmp(buf, "0", 1) == 0) {
+ enabled = 0;
+ } else {
+ printk(KERN_ERR "netconsole: invalid argument: %s\n", buf);
+ return -EINVAL;
+ }
+ spin_lock(&target_list_lock);
+ nt->enabled = enabled;
+ spin_unlock(&target_list_lock);
+
+ return count;
+}
+
static ssize_t store_remove(struct netconsole_target *nt, const char *buf,
size_t count)
{
@@ -216,6 +265,8 @@ static NETCON_CLASS_ATTR(remote_ip, S_IR
static NETCON_CLASS_ATTR(local_mac, S_IRUGO, show_local_mac, NULL);
static NETCON_CLASS_ATTR(remote_mac, S_IRUGO | S_IWUSR,
show_remote_mac, store_remote_mac);
+static NETCON_CLASS_ATTR(enabled, S_IRUGO | S_IWUSR,
+ show_enabled, store_enabled);
static NETCON_CLASS_ATTR(remove, S_IWUSR, NULL, store_remove);
static struct attribute *target_attrs[] = {
@@ -227,6 +278,7 @@ static struct attribute *target_attrs[]
&target_attr_remote_ip.attr,
&target_attr_local_mac.attr,
&target_attr_remote_mac.attr,
+ &target_attr_enabled.attr,
&target_attr_remove.attr,
NULL
};
@@ -242,7 +294,7 @@ static ssize_t show_target_attr(struct k
if (na->show)
return na->show(nt, buffer);
else
- return -EACCES;
+ return -EINVAL;
}
static ssize_t store_target_attr(struct kobject *kobj,
@@ -256,7 +308,7 @@ static ssize_t store_target_attr(struct
if (na->store)
return na->store(nt, buffer, count);
else
- return -EACCES;
+ return -EINVAL;
}
static void release_target(struct kobject *kobj)
@@ -322,6 +374,7 @@ static int add_target(char* target_confi
atomic_inc(&target_count);
new_target->id = atomic_read(&target_count);
+ new_target->enabled = 1;
printk(KERN_INFO "netconsole: add target: "
"remote ip_addr=%d.%d.%d.%d remote port=%d\n",
@@ -368,7 +421,8 @@ static void write_msg(struct console *co
for(left = len; left; ) {
frag = min(left, MAX_PRINT_CHUNK);
list_for_each_entry(target, &target_list, list) {
- netpoll_send_udp(&target->np, msg, frag);
+ if (target->enabled)
+ netpoll_send_udp(&target->np, msg, frag);
}
msg += frag;
left -= frag;
--
Keiichi KII
NEC Corporation OSS Promotion Center
E-mail: [email protected]
From: Keiichi KII <[email protected]>
This patch contains switch function of netpoll.
If "enabled" attribute of certain port is '1', this port is used
and the configurations of this port are uable to change.
If "enabled" attribute of certain port is '0', this port isn't used
and the configurations of this port are able to change.
-+- /sys/class/misc/
|-+- netconsole/
|-+- port1/
| |--- id [r--r--r--] id
| |--- enabled [rw-r--r--] 0: disable 1: enable, writable
| ...
|--- port2/
...
Signed-off-by: Keiichi KII <[email protected]>
Signed-off-by: Takayoshi Kochi <[email protected]>
---
--- linux-mm/drivers/net/netconsole.c 2006-12-26 14:19:01.481857000 +0900
+++ enhanced-netconsole/drivers/net/netconsole.c.add 2006-12-25 16:45:05.121887750 +0900
@@ -335,6 +335,30 @@ static struct miscdevice netconsole_misc
.name = "netconsole",
};
+static ssize_t store_miscdev_add(struct class_device *cdev,
+ const char *buf, size_t count)
+{
+ char *target_param;
+
+ target_param = kmalloc(count+1, GFP_KERNEL);
+ if (!target_param) {
+ printk(KERN_ERR "netconsole: kmalloc() failed!\n");
+ return -ENOMEM;
+ }
+
+ strcpy(target_param, buf);
+ if (target_param[count - 1] == '\n')
+ target_param[count - 1] = '\0';
+
+ printk(KERN_INFO "netconsole: config = [%s]\n", target_param);
+ add_target(target_param);
+ kfree(target_param);
+
+ return count;
+}
+
+static CLASS_DEVICE_ATTR(add, S_IWUSR, NULL, store_miscdev_add);
+
static struct netpoll np = {
.name = "netconsole",
.dev_name = "eth0",
@@ -464,6 +488,9 @@ static int __init init_netconsole(void)
register_console(&netconsole);
+ class_device_create_file(netconsole_miscdev.class,
+ &class_device_attr_add);
+
if(!strlen(config)) {
printk(KERN_ERR "netconsole: not configured\n");
return 0;
--
Keiichi KII
NEC Corporation OSS Promotion Center
E-mail: [email protected]
Keiichi KII wrote:
> From: Keiichi KII <[email protected]>
>
> This patch contains the following changes.
>
> create a sysfs entry for netconsole in /sys/class/misc.
> This entry has elements related to netconsole as follows.
> You can change configuration of netconsole(writable attributes such as IP
> address, port number and so on) and check current configuration of netconsole.
>
> -+- /sys/class/misc/
> |-+- netconsole/
> |-+- port1/
> | |--- id [r--r--r--] unique port id
> | |--- remove [-w-------] if you write something to "remove",
> | | this port is removed.
>
IMHO this kind of "magic side effect" is a misuse of sysfs. and would
make proper locking
impossible. How do you deal with the dangling reference to the
netconsole object?
f= open (... netconsole/port1/remove")
write(f, "", 1)
sleep(2)
write(f, "", 1) .... this probably would crash...
Maybe having a state variable/sysfs file so you could setup the port and
turn it on/off with write.
> | |--- dev_name [r--r--r--] network interface name
>
Please don't use dev_name, instead use a a symlink. You see if the
device is renamed,
the dev_name will be wrong, but the symlink to the net_device kobject
should be okay.
> | |--- local_ip [rw-r--r--] source IP to use, writable
> | |--- local_port [rw-r--r--] source port number for UDP packets, writable
> | |--- local_mac [r--r--r--] source MAC address
> | |--- remote_ip [rw-r--r--] port number for logging agent, writable
> | |--- remote_port [rw-r--r--] IP address for logging agent, writable
> | ---- remote_mac [rw-r--r--] MAC address for logging agent, writable
> |--- port2/
> |--- port3/
> ...
>
> Signed-off-by: Keiichi KII <[email protected]>
> Signed-off-by: Takayoshi Kochi <[email protected]>
>
>> create a sysfs entry for netconsole in /sys/class/misc.
>> This entry has elements related to netconsole as follows.
>> You can change configuration of netconsole(writable attributes such as IP
>> address, port number and so on) and check current configuration of netconsole.
>>
>> -+- /sys/class/misc/
>> |-+- netconsole/
>> |-+- port1/
>> | |--- id [r--r--r--] unique port id
>> | |--- remove [-w-------] if you write something to "remove",
>> | | this port is removed.
>>
> IMHO this kind of "magic side effect" is a misuse of sysfs. and would
> make proper locking
> impossible. How do you deal with the dangling reference to the
> netconsole object?
I manage the reference by using a list.
If you write something to "remove",
firstly the port entry is removed from sysfs and then
the reference is removed from the list and a resource of the port is freed.
> f= open (... netconsole/port1/remove")
> write(f, "", 1)
> sleep(2)
> write(f, "", 1) .... this probably would crash...
>
>
> Maybe having a state variable/sysfs file so you could setup the port and
> turn it on/off with write.
You are right.
When I tested above program, my machine crashed.
I'm going to rethink the interface for netconsole.
Thanks for your comments.
--
Keiichi KII
NEC Corporation OSS Promotion Center
E-mail: [email protected]