diff options
| -rw-r--r-- | drivers/w1/w1.c | 180 | ||||
| -rw-r--r-- | drivers/w1/w1.h | 32 | ||||
| -rw-r--r-- | drivers/w1/w1_int.c | 17 | ||||
| -rw-r--r-- | drivers/w1/w1_netlink.c | 166 |
4 files changed, 300 insertions, 95 deletions
diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 97b35cb8b6da..53846c7f24ff 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -79,19 +79,10 @@ static void w1_slave_release(struct device *dev) { struct w1_slave *sl = dev_to_w1_slave(dev); - dev_dbg(dev, "%s: Releasing %s.\n", __func__, sl->name); - - while (atomic_read(&sl->refcnt)) { - dev_dbg(dev, "Waiting for %s to become free: refcnt=%d.\n", - sl->name, atomic_read(&sl->refcnt)); - if (msleep_interruptible(1000)) - flush_signals(current); - } + dev_dbg(dev, "%s: Releasing %s [%p]\n", __func__, sl->name, sl); w1_family_put(sl->family); sl->master->slave_count--; - - complete(&sl->released); } static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -277,7 +268,6 @@ static ssize_t w1_master_attribute_store_pullup(struct device *dev, mutex_lock(&md->mutex); md->enable_pullup = tmp; mutex_unlock(&md->mutex); - wake_up_process(md->thread); return count; } @@ -370,23 +360,20 @@ static ssize_t w1_master_attribute_show_slaves(struct device *dev, { struct w1_master *md = dev_to_w1_master(dev); int c = PAGE_SIZE; + struct list_head *ent, *n; + struct w1_slave *sl = NULL; - mutex_lock(&md->mutex); - - if (md->slave_count == 0) - c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n"); - else { - struct list_head *ent, *n; - struct w1_slave *sl; + mutex_lock(&md->list_mutex); - list_for_each_safe(ent, n, &md->slist) { - sl = list_entry(ent, struct w1_slave, w1_slave_entry); + list_for_each_safe(ent, n, &md->slist) { + sl = list_entry(ent, struct w1_slave, w1_slave_entry); - c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name); - } + c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name); } + if (!sl) + c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n"); - mutex_unlock(&md->mutex); + mutex_unlock(&md->list_mutex); return PAGE_SIZE - c; } @@ -440,19 +427,22 @@ static int w1_atoreg_num(struct device *dev, const char *buf, size_t count, } /* Searches the slaves in the w1_master and returns a pointer or NULL. - * Note: must hold the mutex + * Note: must not hold list_mutex */ struct w1_slave *w1_slave_search_device(struct w1_master *dev, struct w1_reg_num *rn) { struct w1_slave *sl; + mutex_lock(&dev->list_mutex); list_for_each_entry(sl, &dev->slist, w1_slave_entry) { if (sl->reg_num.family == rn->family && sl->reg_num.id == rn->id && sl->reg_num.crc == rn->crc) { + mutex_unlock(&dev->list_mutex); return sl; } } + mutex_unlock(&dev->list_mutex); return NULL; } @@ -509,7 +499,10 @@ static ssize_t w1_master_attribute_store_remove(struct device *dev, mutex_lock(&md->mutex); sl = w1_slave_search_device(md, &rn); if (sl) { - w1_slave_detach(sl); + result = w1_slave_detach(sl); + /* refcnt 0 means it was detached in the call */ + if (result == 0) + result = count; } else { dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family, (unsigned long long)rn.id); @@ -704,7 +697,9 @@ static int __w1_attach_slave_device(struct w1_slave *sl) dev_set_uevent_suppress(&sl->dev, false); kobject_uevent(&sl->dev.kobj, KOBJ_ADD); + mutex_lock(&sl->master->list_mutex); list_add_tail(&sl->w1_slave_entry, &sl->master->slist); + mutex_unlock(&sl->master->list_mutex); return 0; } @@ -731,8 +726,8 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) memset(&msg, 0, sizeof(msg)); memcpy(&sl->reg_num, rn, sizeof(sl->reg_num)); - atomic_set(&sl->refcnt, 0); - init_completion(&sl->released); + atomic_set(&sl->refcnt, 1); + atomic_inc(&sl->master->refcnt); /* slave modules need to be loaded in a context with unlocked mutex */ mutex_unlock(&dev->mutex); @@ -772,23 +767,48 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) return 0; } -void w1_slave_detach(struct w1_slave *sl) +int w1_unref_slave(struct w1_slave *sl) { - struct w1_netlink_msg msg; - - dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__, sl->name, sl); - - list_del(&sl->w1_slave_entry); - - memset(&msg, 0, sizeof(msg)); - memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id)); - msg.type = W1_SLAVE_REMOVE; - w1_netlink_send(sl->master, &msg); - - device_unregister(&sl->dev); + struct w1_master *dev = sl->master; + int refcnt; + mutex_lock(&dev->list_mutex); + refcnt = atomic_sub_return(1, &sl->refcnt); + if (refcnt == 0) { + struct w1_netlink_msg msg; + + dev_dbg(&sl->dev, "%s: detaching %s [%p].\n", __func__, + sl->name, sl); + + list_del(&sl->w1_slave_entry); + + memset(&msg, 0, sizeof(msg)); + memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id)); + msg.type = W1_SLAVE_REMOVE; + w1_netlink_send(sl->master, &msg); + + device_unregister(&sl->dev); + #ifdef DEBUG + memset(sl, 0, sizeof(*sl)); + #endif + kfree(sl); + } + atomic_dec(&dev->refcnt); + mutex_unlock(&dev->list_mutex); + return refcnt; +} - wait_for_completion(&sl->released); - kfree(sl); +int w1_slave_detach(struct w1_slave *sl) +{ + /* Only detach a slave once as it decreases the refcnt each time. */ + int destroy_now; + mutex_lock(&sl->master->list_mutex); + destroy_now = !test_bit(W1_SLAVE_DETACH, &sl->flags); + set_bit(W1_SLAVE_DETACH, &sl->flags); + mutex_unlock(&sl->master->list_mutex); + + if (destroy_now) + destroy_now = !w1_unref_slave(sl); + return destroy_now ? 0 : -EBUSY; } struct w1_master *w1_search_master_id(u32 id) @@ -817,7 +837,7 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id) mutex_lock(&w1_mlock); list_for_each_entry(dev, &w1_masters, w1_master_entry) { - mutex_lock(&dev->mutex); + mutex_lock(&dev->list_mutex); list_for_each_entry(sl, &dev->slist, w1_slave_entry) { if (sl->reg_num.family == id->family && sl->reg_num.id == id->id && @@ -828,7 +848,7 @@ struct w1_slave *w1_search_slave(struct w1_reg_num *id) break; } } - mutex_unlock(&dev->mutex); + mutex_unlock(&dev->list_mutex); if (found) break; @@ -848,6 +868,7 @@ void w1_reconnect_slaves(struct w1_family *f, int attach) dev_dbg(&dev->dev, "Reconnecting slaves in device %s " "for family %02x.\n", dev->name, f->fid); mutex_lock(&dev->mutex); + mutex_lock(&dev->list_mutex); list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { /* If it is a new family, slaves with the default * family driver and are that family will be @@ -859,14 +880,19 @@ void w1_reconnect_slaves(struct w1_family *f, int attach) (!attach && sl->family->fid == f->fid)) { struct w1_reg_num rn; + mutex_unlock(&dev->list_mutex); memcpy(&rn, &sl->reg_num, sizeof(rn)); - w1_slave_detach(sl); - - w1_attach_slave_device(dev, &rn); + /* If it was already in use let the automatic + * scan pick it up again later. + */ + if (!w1_slave_detach(sl)) + w1_attach_slave_device(dev, &rn); + mutex_lock(&dev->list_mutex); } } dev_dbg(&dev->dev, "Reconnecting slaves in device %s " "has been finished.\n", dev->name); + mutex_unlock(&dev->list_mutex); mutex_unlock(&dev->mutex); } mutex_unlock(&w1_mlock); @@ -1020,17 +1046,24 @@ void w1_search_process_cb(struct w1_master *dev, u8 search_type, { struct w1_slave *sl, *sln; + mutex_lock(&dev->list_mutex); list_for_each_entry(sl, &dev->slist, w1_slave_entry) clear_bit(W1_SLAVE_ACTIVE, &sl->flags); + mutex_unlock(&dev->list_mutex); w1_search_devices(dev, search_type, cb); + mutex_lock(&dev->list_mutex); list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { - if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl) + if (!test_bit(W1_SLAVE_ACTIVE, &sl->flags) && !--sl->ttl) { + mutex_unlock(&dev->list_mutex); w1_slave_detach(sl); + mutex_lock(&dev->list_mutex); + } else if (test_bit(W1_SLAVE_ACTIVE, &sl->flags)) sl->ttl = dev->slave_ttl; } + mutex_unlock(&dev->list_mutex); if (dev->search_count > 0) dev->search_count--; @@ -1041,6 +1074,26 @@ static void w1_search_process(struct w1_master *dev, u8 search_type) w1_search_process_cb(dev, search_type, w1_slave_found); } +int w1_process_callbacks(struct w1_master *dev) +{ + int ret = 0; + struct w1_async_cmd *async_cmd, *async_n; + + /* The list can be added to in another thread, loop until it is empty */ + while (!list_empty(&dev->async_list)) { + list_for_each_entry_safe(async_cmd, async_n, &dev->async_list, + async_entry) { + /* drop the lock, if it is a search it can take a long + * time */ + mutex_unlock(&dev->list_mutex); + async_cmd->cb(dev, async_cmd); + ret = 1; + mutex_lock(&dev->list_mutex); + } + } + return ret; +} + int w1_process(void *data) { struct w1_master *dev = (struct w1_master *) data; @@ -1048,23 +1101,46 @@ int w1_process(void *data) * time can be calculated in jiffies once. */ const unsigned long jtime = msecs_to_jiffies(w1_timeout * 1000); + /* remainder if it woke up early */ + unsigned long jremain = 0; - while (!kthread_should_stop()) { - if (dev->search_count) { + for (;;) { + + if (!jremain && dev->search_count) { mutex_lock(&dev->mutex); w1_search_process(dev, W1_SEARCH); mutex_unlock(&dev->mutex); } + mutex_lock(&dev->list_mutex); + /* Note, w1_process_callback drops the lock while processing, + * but locks it again before returning. + */ + if (!w1_process_callbacks(dev) && jremain) { + /* a wake up is either to stop the thread, process + * callbacks, or search, it isn't process callbacks, so + * schedule a search. + */ + jremain = 1; + } + try_to_freeze(); __set_current_state(TASK_INTERRUPTIBLE); + /* hold list_mutex until after interruptible to prevent loosing + * the wakeup signal when async_cmd is added. + */ + mutex_unlock(&dev->list_mutex); + if (kthread_should_stop()) break; /* Only sleep when the search is active. */ - if (dev->search_count) - schedule_timeout(jtime); + if (dev->search_count) { + if (!jremain) + jremain = jtime; + jremain = schedule_timeout(jremain); + } else schedule(); } diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h index 3376bfbb10f4..a096ef40119e 100644 --- a/drivers/w1/w1.h +++ b/drivers/w1/w1.h @@ -58,6 +58,7 @@ struct w1_reg_num #define W1_RESUME_CMD 0xA5 #define W1_SLAVE_ACTIVE 0 +#define W1_SLAVE_DETACH 1 struct w1_slave { @@ -74,7 +75,6 @@ struct w1_slave struct w1_family *family; void *family_data; struct device dev; - struct completion released; }; typedef void (*w1_slave_found_callback)(struct w1_master *, u64); @@ -171,7 +171,14 @@ struct w1_master struct list_head w1_master_entry; struct module *owner; unsigned char name[W1_MAXNAMELEN]; + /* list_mutex protects just slist and async_list so slaves can be + * searched for and async commands added while the master has + * w1_master.mutex locked and is operating on the bus. + * lock order w1_mlock, w1_master.mutex, w1_master_list_mutex + */ + struct mutex list_mutex; struct list_head slist; + struct list_head async_list; int max_slave_count, slave_count; unsigned long attempts; int slave_ttl; @@ -205,11 +212,29 @@ struct w1_master u32 seq; }; +/** + * struct w1_async_cmd - execute callback from the w1_process kthread + * @async_entry: link entry + * @cb: callback function, must list_del and destroy this list before + * returning + * + * When inserted into the w1_master async_list, w1_process will execute + * the callback. Embed this into the structure with the command details. + */ +struct w1_async_cmd { + struct list_head async_entry; + void (*cb)(struct w1_master *dev, struct w1_async_cmd *async_cmd); +}; + int w1_create_master_attributes(struct w1_master *); void w1_destroy_master_attributes(struct w1_master *master); void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); +/* call w1_unref_slave to release the reference counts w1_search_slave added */ struct w1_slave *w1_search_slave(struct w1_reg_num *id); +/* decrements the reference on sl->master and sl, and cleans up if zero + * returns the reference count after it has been decremented */ +int w1_unref_slave(struct w1_slave *sl); void w1_slave_found(struct w1_master *dev, u64 rn); void w1_search_process_cb(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb); @@ -224,7 +249,8 @@ struct w1_master *w1_search_master_id(u32 id); */ void w1_reconnect_slaves(struct w1_family *f, int attach); int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn); -void w1_slave_detach(struct w1_slave *sl); +/* 0 success, otherwise EBUSY */ +int w1_slave_detach(struct w1_slave *sl); u8 w1_triplet(struct w1_master *dev, int bdir); void w1_write_8(struct w1_master *, u8); @@ -260,6 +286,8 @@ extern int w1_max_slave_ttl; extern struct list_head w1_masters; extern struct mutex w1_mlock; +/* returns 1 if there were commands to executed 0 otherwise */ +extern int w1_process_callbacks(struct w1_master *dev); extern int w1_process(void *); #endif /* __KERNEL__ */ diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index 423f3c2b9e7d..66b2caae48f3 100644 --- a/drivers/w1/w1_int.c +++ b/drivers/w1/w1_int.c @@ -75,8 +75,10 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl, atomic_set(&dev->refcnt, 2); INIT_LIST_HEAD(&dev->slist); + INIT_LIST_HEAD(&dev->async_list); mutex_init(&dev->mutex); mutex_init(&dev->bus_mutex); + mutex_init(&dev->list_mutex); memcpy(&dev->dev, device, sizeof(struct device)); dev_set_name(&dev->dev, "w1_bus_master%u", dev->id); @@ -188,17 +190,22 @@ void __w1_remove_master_device(struct w1_master *dev) struct w1_netlink_msg msg; struct w1_slave *sl, *sln; - set_bit(W1_ABORT_SEARCH, &dev->flags); - kthread_stop(dev->thread); - mutex_lock(&w1_mlock); list_del(&dev->w1_master_entry); mutex_unlock(&w1_mlock); + set_bit(W1_ABORT_SEARCH, &dev->flags); + kthread_stop(dev->thread); + mutex_lock(&dev->mutex); - list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) + mutex_lock(&dev->list_mutex); + list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) { + mutex_unlock(&dev->list_mutex); w1_slave_detach(sl); + mutex_lock(&dev->list_mutex); + } w1_destroy_master_attributes(dev); + mutex_unlock(&dev->list_mutex); mutex_unlock(&dev->mutex); atomic_dec(&dev->refcnt); @@ -208,7 +215,9 @@ void __w1_remove_master_device(struct w1_master *dev) if (msleep_interruptible(1000)) flush_signals(current); + w1_process_callbacks(dev); } + w1_process_callbacks(dev); memset(&msg, 0, sizeof(msg)); msg.id.mst.id = dev->id; diff --git a/drivers/w1/w1_netlink.c b/drivers/w1/w1_netlink.c index 747174be7b50..06d614af1166 100644 --- a/drivers/w1/w1_netlink.c +++ b/drivers/w1/w1_netlink.c @@ -119,10 +119,12 @@ static int w1_get_slaves(struct w1_master *dev, if (req_cmd->cmd == W1_CMD_LIST_SLAVES) { __u64 rn; + mutex_lock(&dev->list_mutex); list_for_each_entry(sl, &dev->slist, w1_slave_entry) { memcpy(&rn, &sl->reg_num, sizeof(rn)); w1_send_slave(dev, rn); } + mutex_unlock(&dev->list_mutex); } else { w1_search_process_cb(dev, cmd->cmd == W1_CMD_ALARM_SEARCH ? W1_ALARM_SEARCH : W1_SEARCH, w1_found_send_slave); @@ -368,29 +370,134 @@ static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rm return error; } +/* Bundle together a reference count, the full message, and broken out + * commands to be executed on each w1 master kthread in one memory allocation. + */ +struct w1_cb_block { + atomic_t refcnt; + struct cn_msg msg; + /* cn_msg data */ + /* one or more variable length struct w1_cb_node */ +}; +struct w1_cb_node { + struct w1_async_cmd async; + /* pointers within w1_cb_block and msg data */ + struct w1_cb_block *block; + struct w1_netlink_msg *m; + struct w1_slave *sl; + struct w1_master *dev; +}; + +static void w1_process_cb(struct w1_master *dev, struct w1_async_cmd *async_cmd) +{ + struct w1_cb_node *node = container_of(async_cmd, struct w1_cb_node, + async); + u16 mlen = node->m->len; + u8 *cmd_data = node->m->data; + int err = 0; + struct w1_slave *sl = node->sl; + struct w1_netlink_cmd *cmd = NULL; + + mutex_lock(&dev->mutex); + if (sl && w1_reset_select_slave(sl)) + err = -ENODEV; + + while (mlen && !err) { + cmd = (struct w1_netlink_cmd *)cmd_data; + + if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) { + err = -E2BIG; + break; + } + + if (sl) + err = w1_process_command_slave(sl, &node->block->msg, + node->m, cmd); + else + err = w1_process_command_master(dev, &node->block->msg, + node->m, cmd); + + w1_netlink_send_error(&node->block->msg, node->m, cmd, err); + err = 0; + + cmd_data += cmd->len + sizeof(struct w1_netlink_cmd); + mlen -= cmd->len + sizeof(struct w1_netlink_cmd); + } + + if (!cmd || err) + w1_netlink_send_error(&node->block->msg, node->m, cmd, err); + + if (sl) + w1_unref_slave(sl); + else + atomic_dec(&dev->refcnt); + mutex_unlock(&dev->mutex); + + mutex_lock(&dev->list_mutex); + list_del(&async_cmd->async_entry); + mutex_unlock(&dev->list_mutex); + + if (atomic_sub_return(1, &node->block->refcnt) == 0) + kfree(node->block); +} + static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) { struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1); - struct w1_netlink_cmd *cmd; struct w1_slave *sl; struct w1_master *dev; + u16 msg_len; int err = 0; + struct w1_cb_block *block = NULL; + struct w1_cb_node *node = NULL; + int node_count = 0; + + /* Count the number of master or slave commands there are to allocate + * space for one cb_node each. + */ + msg_len = msg->len; + while (msg_len && !err) { + if (m->len + sizeof(struct w1_netlink_msg) > msg_len) { + err = -E2BIG; + break; + } + + if (m->type == W1_MASTER_CMD || m->type == W1_SLAVE_CMD) + ++node_count; + + msg_len -= sizeof(struct w1_netlink_msg) + m->len; + m = (struct w1_netlink_msg *)(((u8 *)m) + + sizeof(struct w1_netlink_msg) + m->len); + } + m = (struct w1_netlink_msg *)(msg + 1); + if (node_count) { + /* msg->len doesn't include itself */ + long size = sizeof(struct w1_cb_block) + msg->len + + node_count*sizeof(struct w1_cb_node); + block = kmalloc(size, GFP_KERNEL); + if (!block) { + w1_netlink_send_error(msg, m, NULL, -ENOMEM); + return; + } + atomic_set(&block->refcnt, 1); + memcpy(&block->msg, msg, sizeof(*msg) + msg->len); + node = (struct w1_cb_node *)((u8 *)block->msg.data + msg->len); + } - while (msg->len && !err) { + msg_len = msg->len; + while (msg_len && !err) { struct w1_reg_num id; u16 mlen = m->len; - u8 *cmd_data = m->data; dev = NULL; sl = NULL; - cmd = NULL; memcpy(&id, m->id.id, sizeof(id)); #if 0 printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n", __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len); #endif - if (m->len + sizeof(struct w1_netlink_msg) > msg->len) { + if (m->len + sizeof(struct w1_netlink_msg) > msg_len) { err = -E2BIG; break; } @@ -415,41 +522,24 @@ static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) if (!mlen) goto out_cont; - mutex_lock(&dev->mutex); + atomic_inc(&block->refcnt); + node->async.cb = w1_process_cb; + node->block = block; + node->m = (struct w1_netlink_msg *)((u8 *)&block->msg + + (size_t)((u8 *)m - (u8 *)msg)); + node->sl = sl; + node->dev = dev; - if (sl && w1_reset_select_slave(sl)) { - err = -ENODEV; - goto out_up; - } - - while (mlen) { - cmd = (struct w1_netlink_cmd *)cmd_data; - - if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) { - err = -E2BIG; - break; - } - - if (sl) - err = w1_process_command_slave(sl, msg, m, cmd); - else - err = w1_process_command_master(dev, msg, m, cmd); + mutex_lock(&dev->list_mutex); + list_add_tail(&node->async.async_entry, &dev->async_list); + wake_up_process(dev->thread); + mutex_unlock(&dev->list_mutex); + ++node; - w1_netlink_send_error(msg, m, cmd, err); - err = 0; - - cmd_data += cmd->len + sizeof(struct w1_netlink_cmd); - mlen -= cmd->len + sizeof(struct w1_netlink_cmd); - } -out_up: - atomic_dec(&dev->refcnt); - if (sl) - atomic_dec(&sl->refcnt); - mutex_unlock(&dev->mutex); out_cont: - if (!cmd || err) - w1_netlink_send_error(msg, m, cmd, err); - msg->len -= sizeof(struct w1_netlink_msg) + m->len; + if (err) + w1_netlink_send_error(msg, m, NULL, err); + msg_len -= sizeof(struct w1_netlink_msg) + m->len; m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len); /* @@ -458,6 +548,8 @@ out_cont: if (err == -ENODEV) err = 0; } + if (block && atomic_sub_return(1, &block->refcnt) == 0) + kfree(block); } int w1_init_netlink(void) |