diff options
Diffstat (limited to 'drivers/block/nbd.c')
| -rw-r--r-- | drivers/block/nbd.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 7e0501c47153..ac07e8c94c79 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -26,6 +26,7 @@ #include <linux/ioctl.h> #include <linux/mutex.h> #include <linux/compiler.h> +#include <linux/completion.h> #include <linux/err.h> #include <linux/kernel.h> #include <linux/slab.h> @@ -80,6 +81,9 @@ struct link_dead_args { #define NBD_RT_DESTROY_ON_DISCONNECT 6 #define NBD_RT_DISCONNECT_ON_CLOSE 7 +#define NBD_DESTROY_ON_DISCONNECT 0 +#define NBD_DISCONNECT_REQUESTED 1 + struct nbd_config { u32 flags; unsigned long runtime_flags; @@ -113,6 +117,9 @@ struct nbd_device { struct list_head list; struct task_struct *task_recv; struct task_struct *task_setup; + + struct completion *destroy_complete; + unsigned long flags; }; #define NBD_CMD_REQUEUED 1 @@ -223,6 +230,16 @@ static void nbd_dev_remove(struct nbd_device *nbd) disk->private_data = NULL; put_disk(disk); } + + /* + * Place this in the last just before the nbd is freed to + * make sure that the disk and the related kobject are also + * totally removed to avoid duplicate creation of the same + * one. + */ + if (test_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags) && nbd->destroy_complete) + complete(nbd->destroy_complete); + kfree(nbd); } @@ -1125,6 +1142,7 @@ static int nbd_disconnect(struct nbd_device *nbd) dev_info(disk_to_dev(nbd->disk), "NBD_DISCONNECT\n"); set_bit(NBD_RT_DISCONNECT_REQUESTED, &config->runtime_flags); + set_bit(NBD_DISCONNECT_REQUESTED, &nbd->flags); send_disconnects(nbd); return 0; } @@ -1636,6 +1654,7 @@ static int nbd_dev_add(int index) nbd->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING; nbd->tag_set.driver_data = nbd; + nbd->destroy_complete = NULL; err = blk_mq_alloc_tag_set(&nbd->tag_set); if (err) @@ -1750,6 +1769,7 @@ static int nbd_genl_size_set(struct genl_info *info, struct nbd_device *nbd) static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info) { + DECLARE_COMPLETION_ONSTACK(destroy_complete); struct nbd_device *nbd = NULL; struct nbd_config *config; int index = -1; @@ -1801,6 +1821,17 @@ again: mutex_unlock(&nbd_index_mutex); return -EINVAL; } + + if (test_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags) && + test_bit(NBD_DISCONNECT_REQUESTED, &nbd->flags)) { + nbd->destroy_complete = &destroy_complete; + mutex_unlock(&nbd_index_mutex); + + /* Wait untill the the nbd stuff is totally destroyed */ + wait_for_completion(&destroy_complete); + goto again; + } + if (!refcount_inc_not_zero(&nbd->refs)) { mutex_unlock(&nbd_index_mutex); if (index == -1) @@ -1855,7 +1886,10 @@ again: if (flags & NBD_CFLAG_DESTROY_ON_DISCONNECT) { set_bit(NBD_RT_DESTROY_ON_DISCONNECT, &config->runtime_flags); + set_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags); put_dev = true; + } else { + clear_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags); } if (flags & NBD_CFLAG_DISCONNECT_ON_CLOSE) { set_bit(NBD_RT_DISCONNECT_ON_CLOSE, @@ -2029,10 +2063,12 @@ static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info) if (!test_and_set_bit(NBD_RT_DESTROY_ON_DISCONNECT, &config->runtime_flags)) put_dev = true; + set_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags); } else { if (test_and_clear_bit(NBD_RT_DESTROY_ON_DISCONNECT, &config->runtime_flags)) refcount_inc(&nbd->refs); + clear_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags); } if (flags & NBD_CFLAG_DISCONNECT_ON_CLOSE) { |