diff options
Diffstat (limited to 'drivers/net/netdevsim/bus.c')
| -rw-r--r-- | drivers/net/netdevsim/bus.c | 43 |
1 files changed, 40 insertions, 3 deletions
diff --git a/drivers/net/netdevsim/bus.c b/drivers/net/netdevsim/bus.c index 6aeed0c600f8..c086d1e522dc 100644 --- a/drivers/net/netdevsim/bus.c +++ b/drivers/net/netdevsim/bus.c @@ -17,6 +17,7 @@ static DEFINE_IDA(nsim_bus_dev_ids); static LIST_HEAD(nsim_bus_dev_list); static DEFINE_MUTEX(nsim_bus_dev_list_lock); +static bool nsim_bus_enable; static struct nsim_bus_dev *to_nsim_bus_dev(struct device *dev) { @@ -99,6 +100,9 @@ new_port_store(struct device *dev, struct device_attribute *attr, unsigned int port_index; int ret; + /* Prevent to use nsim_bus_dev before initialization. */ + if (!smp_load_acquire(&nsim_bus_dev->init)) + return -EBUSY; ret = kstrtouint(buf, 0, &port_index); if (ret) return ret; @@ -116,6 +120,9 @@ del_port_store(struct device *dev, struct device_attribute *attr, unsigned int port_index; int ret; + /* Prevent to use nsim_bus_dev before initialization. */ + if (!smp_load_acquire(&nsim_bus_dev->init)) + return -EBUSY; ret = kstrtouint(buf, 0, &port_index); if (ret) return ret; @@ -179,15 +186,30 @@ new_device_store(struct bus_type *bus, const char *buf, size_t count) pr_err("Format for adding new device is \"id port_count\" (uint uint).\n"); return -EINVAL; } - nsim_bus_dev = nsim_bus_dev_new(id, port_count); - if (IS_ERR(nsim_bus_dev)) - return PTR_ERR(nsim_bus_dev); mutex_lock(&nsim_bus_dev_list_lock); + /* Prevent to use resource before initialization. */ + if (!smp_load_acquire(&nsim_bus_enable)) { + err = -EBUSY; + goto err; + } + + nsim_bus_dev = nsim_bus_dev_new(id, port_count); + if (IS_ERR(nsim_bus_dev)) { + err = PTR_ERR(nsim_bus_dev); + goto err; + } + + /* Allow using nsim_bus_dev */ + smp_store_release(&nsim_bus_dev->init, true); + list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list); mutex_unlock(&nsim_bus_dev_list_lock); return count; +err: + mutex_unlock(&nsim_bus_dev_list_lock); + return err; } static BUS_ATTR_WO(new_device); @@ -215,6 +237,11 @@ del_device_store(struct bus_type *bus, const char *buf, size_t count) err = -ENOENT; mutex_lock(&nsim_bus_dev_list_lock); + /* Prevent to use resource before initialization. */ + if (!smp_load_acquire(&nsim_bus_enable)) { + mutex_unlock(&nsim_bus_dev_list_lock); + return -EBUSY; + } list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) { if (nsim_bus_dev->dev.id != id) continue; @@ -284,6 +311,8 @@ nsim_bus_dev_new(unsigned int id, unsigned int port_count) nsim_bus_dev->dev.type = &nsim_bus_dev_type; nsim_bus_dev->port_count = port_count; nsim_bus_dev->initial_net = current->nsproxy->net_ns; + /* Disallow using nsim_bus_dev */ + smp_store_release(&nsim_bus_dev->init, false); err = device_register(&nsim_bus_dev->dev); if (err) @@ -299,6 +328,8 @@ err_nsim_bus_dev_free: static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev) { + /* Disallow using nsim_bus_dev */ + smp_store_release(&nsim_bus_dev->init, false); device_unregister(&nsim_bus_dev->dev); ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id); kfree(nsim_bus_dev); @@ -320,6 +351,8 @@ int nsim_bus_init(void) err = driver_register(&nsim_driver); if (err) goto err_bus_unregister; + /* Allow using resources */ + smp_store_release(&nsim_bus_enable, true); return 0; err_bus_unregister: @@ -331,12 +364,16 @@ void nsim_bus_exit(void) { struct nsim_bus_dev *nsim_bus_dev, *tmp; + /* Disallow using resources */ + smp_store_release(&nsim_bus_enable, false); + mutex_lock(&nsim_bus_dev_list_lock); list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) { list_del(&nsim_bus_dev->list); nsim_bus_dev_del(nsim_bus_dev); } mutex_unlock(&nsim_bus_dev_list_lock); + driver_unregister(&nsim_driver); bus_unregister(&nsim_bus); } |