drbd: Converted drbd_cfg_mutex into drbd_cfg_rwsem

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Philipp Reisner 2011-04-13 14:21:29 -07:00
parent 695d08fa94
commit ef35626284
3 changed files with 24 additions and 17 deletions

View File

@ -171,7 +171,9 @@ drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) {
extern struct ratelimit_state drbd_ratelimit_state;
extern struct idr minors;
extern struct list_head drbd_tconns;
extern struct mutex drbd_cfg_mutex;
extern struct rw_semaphore drbd_cfg_rwsem;
/* drbd_cfg_rwsem protects: drbd_tconns list,
note: non sleeping iterations over the idrs are protoected by RCU */
/* on the wire */
enum drbd_packet {

View File

@ -120,7 +120,7 @@ module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0
*/
struct idr minors;
struct list_head drbd_tconns; /* list of struct drbd_tconn */
DEFINE_MUTEX(drbd_cfg_mutex);
DECLARE_RWSEM(drbd_cfg_rwsem);
struct kmem_cache *drbd_request_cache;
struct kmem_cache *drbd_ee_cache; /* peer requests */
@ -2330,14 +2330,14 @@ struct drbd_tconn *conn_by_name(const char *name)
if (!name || !name[0])
return NULL;
mutex_lock(&drbd_cfg_mutex);
down_read(&drbd_cfg_rwsem);
list_for_each_entry(tconn, &drbd_tconns, all_tconn) {
if (!strcmp(tconn->name, name))
goto found;
}
tconn = NULL;
found:
mutex_unlock(&drbd_cfg_mutex);
up_read(&drbd_cfg_rwsem);
return tconn;
}
@ -2404,9 +2404,9 @@ struct drbd_tconn *drbd_new_tconn(const char *name)
DRBD_ON_NO_DATA_DEF, /* on_no_data */
};
mutex_lock(&drbd_cfg_mutex);
down_write(&drbd_cfg_rwsem);
list_add_tail(&tconn->all_tconn, &drbd_tconns);
mutex_unlock(&drbd_cfg_mutex);
up_write(&drbd_cfg_rwsem);
return tconn;

View File

@ -1905,7 +1905,7 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info)
new_my_addr = (struct sockaddr *)&new_conf->my_addr;
new_peer_addr = (struct sockaddr *)&new_conf->peer_addr;
/* No need to take drbd_cfg_mutex here. All reconfiguration is
/* No need to take drbd_cfg_rwsem here. All reconfiguration is
* strictly serialized on genl_lock(). We are protected against
* concurrent reconfiguration/addition/deletion */
list_for_each_entry(oconn, &drbd_tconns, all_tconn) {
@ -2581,7 +2581,7 @@ int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb)
*/
/* synchronize with drbd_new_tconn/drbd_free_tconn */
mutex_lock(&drbd_cfg_mutex);
down_read(&drbd_cfg_rwsem);
next_tconn:
/* revalidate iterator position */
list_for_each_entry(tmp, &drbd_tconns, all_tconn) {
@ -2642,7 +2642,7 @@ next_tconn:
}
out:
mutex_unlock(&drbd_cfg_mutex);
up_read(&drbd_cfg_rwsem);
/* where to start the next iteration */
cb->args[0] = (long)pos;
cb->args[1] = (pos == tconn) ? volume + 1 : 0;
@ -2894,9 +2894,9 @@ int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info)
if (retcode != NO_ERROR)
goto out;
mutex_lock(&drbd_cfg_mutex);
down_write(&drbd_cfg_rwsem);
retcode = adm_delete_minor(adm_ctx.mdev);
mutex_unlock(&drbd_cfg_mutex);
up_write(&drbd_cfg_rwsem);
/* if this was the last volume of this connection,
* this will terminate all threads */
if (retcode == NO_ERROR)
@ -2924,7 +2924,7 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
goto out;
}
mutex_lock(&drbd_cfg_mutex);
down_read(&drbd_cfg_rwsem);
/* demote */
idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {
retcode = drbd_set_role(mdev, R_SECONDARY, 0);
@ -2951,14 +2951,17 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
goto out_unlock;
}
}
up_read(&drbd_cfg_rwsem);
/* delete volumes */
down_write(&drbd_cfg_rwsem);
idr_for_each_entry(&adm_ctx.tconn->volumes, mdev, i) {
retcode = adm_delete_minor(mdev);
if (retcode != NO_ERROR) {
/* "can not happen" */
drbd_msg_put_info("failed to delete volume");
goto out_unlock;
up_write(&drbd_cfg_rwsem);
goto out;
}
}
@ -2973,10 +2976,12 @@ int drbd_adm_down(struct sk_buff *skb, struct genl_info *info)
/* "can not happen" */
retcode = ERR_CONN_IN_USE;
drbd_msg_put_info("failed to delete connection");
goto out_unlock;
}
up_write(&drbd_cfg_rwsem);
goto out;
out_unlock:
mutex_unlock(&drbd_cfg_mutex);
up_read(&drbd_cfg_rwsem);
out:
drbd_adm_finish(info, retcode);
return 0;
@ -2992,14 +2997,14 @@ int drbd_adm_delete_connection(struct sk_buff *skb, struct genl_info *info)
if (retcode != NO_ERROR)
goto out;
mutex_lock(&drbd_cfg_mutex);
down_write(&drbd_cfg_rwsem);
if (conn_lowest_minor(adm_ctx.tconn) < 0) {
drbd_free_tconn(adm_ctx.tconn);
retcode = NO_ERROR;
} else {
retcode = ERR_CONN_IN_USE;
}
mutex_unlock(&drbd_cfg_mutex);
up_write(&drbd_cfg_rwsem);
out:
drbd_adm_finish(info, retcode);