2007-12-26 03:11:04

by Joonwoo Park

[permalink] [raw]
Subject: [PATCH] netconsole: register cmdline netconsole configs to configfs

This patch intorduces cmdline netconsole configs to register to configfs with dynamic netconsole. Satyam Sharma who designed shiny
dynamic reconfiguration for netconsole, mentioned about this issue already. (http://lkml.org/lkml/2007/7/29/360)
But I think, without separately managing of two kind of netconsole target objects, it's possible by using config_group instead of
config_item in the netconsole_target and default_groups feature of configfs.

Patch was tested with configuration creation/destruction by kernel and module.
And it makes possible to enable/disable, modify and review netconsole target configs from cmdline.

Signed-off-by: Joonwoo Park <[email protected]>
---
drivers/net/netconsole.c | 91 ++++++++++++++++++++++++++++++++++++----------
1 files changed, 72 insertions(+), 19 deletions(-)

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 5ffbb88..04e4555 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -93,7 +93,7 @@ static DEFINE_SPINLOCK(target_list_lock);
struct netconsole_target {
struct list_head list;
#ifdef CONFIG_NETCONSOLE_DYNAMIC
- struct config_item item;
+ struct config_group group;
#endif
int enabled;
struct netpoll np;
@@ -103,16 +103,49 @@ struct netconsole_target {

static struct configfs_subsystem netconsole_subsys;

-static int __init dynamic_netconsole_init(void)
+static void netconsole_target_put(struct netconsole_target *nt);
+static struct config_item_type netconsole_target_type;
+
+static int __init dynamic_netconsole_init(int defaults)
{
+ int err;
+ unsigned long flags;
config_group_init(&netconsole_subsys.su_group);
+
+ if (defaults > 0) {
+ struct list_head *pos;
+ struct config_group **groups;
+ int i = 0;
+
+ groups = kcalloc(defaults, sizeof(struct config_group *),
+ GFP_KERNEL);
+ if (!groups)
+ return -ENOMEM;
+
+ spin_lock_irqsave(&target_list_lock, flags);
+ list_for_each(pos, &target_list) {
+ struct netconsole_target *nt;
+ nt = list_entry(pos, struct netconsole_target, list);
+ groups[i] = &nt->group;
+ i++;
+ }
+ spin_unlock_irqrestore(&target_list_lock, flags);
+ netconsole_subsys.su_group.default_groups = groups;
+ }
+
mutex_init(&netconsole_subsys.su_mutex);
- return configfs_register_subsystem(&netconsole_subsys);
+
+ err = configfs_register_subsystem(&netconsole_subsys);
+ if (err)
+ kfree(netconsole_subsys.su_group.default_groups);
+
+ return err;
}

static void __exit dynamic_netconsole_exit(void)
{
configfs_unregister_subsystem(&netconsole_subsys);
+ kfree(netconsole_subsys.su_group.default_groups);
}

/*
@@ -122,14 +155,23 @@ static void __exit dynamic_netconsole_exit(void)
*/
static void netconsole_target_get(struct netconsole_target *nt)
{
- if (config_item_name(&nt->item))
- config_item_get(&nt->item);
+ if (config_item_name(&nt->group.cg_item))
+ config_item_get(&nt->group.cg_item);
}

static void netconsole_target_put(struct netconsole_target *nt)
{
- if (config_item_name(&nt->item))
- config_item_put(&nt->item);
+ if (config_item_name(&nt->group.cg_item))
+ config_item_put(&nt->group.cg_item);
+}
+
+static void dynamic_netconsole_init_type_name(struct netconsole_target *nt,
+ int index)
+{
+ char name[16];
+ snprintf(name, sizeof(name), "netcon%d", index);
+ config_item_init_type_name(&nt->group.cg_item, name,
+ &netconsole_target_type);
}

#else /* !CONFIG_NETCONSOLE_DYNAMIC */
@@ -155,6 +197,11 @@ static void netconsole_target_put(struct netconsole_target *nt)
{
}

+static void dynamic_netconsole_init_type_name(struct netconsole_target *nt,
+ int index)
+{
+}
+
#endif /* CONFIG_NETCONSOLE_DYNAMIC */

/* Allocate new target (from boot/module param) and setup netpoll for it */
@@ -236,8 +283,8 @@ struct netconsole_target_attr {
static struct netconsole_target *to_target(struct config_item *item)
{
return item ?
- container_of(item, struct netconsole_target, item) :
- NULL;
+ container_of(to_config_group(item), struct netconsole_target,
+ group) : NULL;
}

/*
@@ -368,7 +415,7 @@ static ssize_t store_dev_name(struct netconsole_target *nt,
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
"disable to update parameters\n",
- config_item_name(&nt->item));
+ config_item_name(&nt->group.cg_item));
return -EINVAL;
}

@@ -392,7 +439,7 @@ static ssize_t store_local_port(struct netconsole_target *nt,
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
"disable to update parameters\n",
- config_item_name(&nt->item));
+ config_item_name(&nt->group.cg_item));
return -EINVAL;
}

@@ -415,7 +462,7 @@ static ssize_t store_remote_port(struct netconsole_target *nt,
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
"disable to update parameters\n",
- config_item_name(&nt->item));
+ config_item_name(&nt->group.cg_item));
return -EINVAL;
}

@@ -435,7 +482,7 @@ static ssize_t store_local_ip(struct netconsole_target *nt,
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
"disable to update parameters\n",
- config_item_name(&nt->item));
+ config_item_name(&nt->group.cg_item));
return -EINVAL;
}

@@ -451,7 +498,7 @@ static ssize_t store_remote_ip(struct netconsole_target *nt,
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
"disable to update parameters\n",
- config_item_name(&nt->item));
+ config_item_name(&nt->group.cg_item));
return -EINVAL;
}

@@ -471,7 +518,7 @@ static ssize_t store_remote_mac(struct netconsole_target *nt,
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
"disable to update parameters\n",
- config_item_name(&nt->item));
+ config_item_name(&nt->group.cg_item));
return -EINVAL;
}

@@ -606,14 +653,15 @@ static struct config_item *make_netconsole_target(struct config_group *group,
memset(nt->np.remote_mac, 0xff, ETH_ALEN);

/* Initialize the config_item member */
- config_item_init_type_name(&nt->item, name, &netconsole_target_type);
+ config_item_init_type_name(&nt->group.cg_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;
+ return &nt->group.cg_item;
}

static void drop_netconsole_target(struct config_group *group,
@@ -633,7 +681,7 @@ static void drop_netconsole_target(struct config_group *group,
if (nt->enabled)
netpoll_cleanup(&nt->np);

- config_item_put(&nt->item);
+ config_item_put(&nt->group.cg_item);
}

static struct configfs_group_operations netconsole_subsys_group_ops = {
@@ -743,6 +791,7 @@ static int __init init_netconsole(void)
unsigned long flags;
char *target_config;
char *input = config;
+ int i = 0;

if (strnlen(input, MAX_PARAM_LENGTH)) {
while ((target_config = strsep(&input, ";"))) {
@@ -751,9 +800,13 @@ static int __init init_netconsole(void)
err = PTR_ERR(nt);
goto fail;
}
+
+ dynamic_netconsole_init_type_name(nt, i);
+
spin_lock_irqsave(&target_list_lock, flags);
list_add(&nt->list, &target_list);
spin_unlock_irqrestore(&target_list_lock, flags);
+ i++;
}
}

@@ -761,7 +814,7 @@ static int __init init_netconsole(void)
if (err)
goto fail;

- err = dynamic_netconsole_init();
+ err = dynamic_netconsole_init(i);
if (err)
goto undonotifier;

---

Thanks.
Joonwoo