diff options
Diffstat (limited to 'src/kernel/blk.c')
| -rw-r--r-- | src/kernel/blk.c | 57 |
1 files changed, 44 insertions, 13 deletions
diff --git a/src/kernel/blk.c b/src/kernel/blk.c index 69d02d5..43251d3 100644 --- a/src/kernel/blk.c +++ b/src/kernel/blk.c @@ -33,6 +33,25 @@ #define dnbd3_req_special(req) \ blk_rq_is_private(req) +static int dnbd3_close_device(dnbd3_device_t *dev) +{ + int result; + dnbd3_blk_fail_all_requests(dev); + dev->panic = 0; + dev->discover = 0; + result = dnbd3_net_disconnect(dev); + dnbd3_blk_fail_all_requests(dev); + blk_mq_freeze_queue(dev->queue); + set_capacity(dev->disk, 0); + blk_mq_unfreeze_queue(dev->queue); + if (dev->imgname) + { + kfree(dev->imgname); + dev->imgname = NULL; + } + return result; +} + static int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) { int result = -100; @@ -45,8 +64,7 @@ static int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int dnbd3_server_t *alt_server; unsigned long irqflags; int i = 0; - - while (dev->disconnecting) { /* do nothing */ } + u8 locked = 0; if (arg != 0) { @@ -83,6 +101,12 @@ static int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int switch (cmd) { case IOCTL_OPEN: + if (atomic_cmpxchg(&dev->connection_lock, 0, 1) != 0) + { + result = -EBUSY; + break; + } + locked = 1; if (dev->imgname != NULL) { result = -EBUSY; @@ -165,20 +189,22 @@ static int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int break; case IOCTL_CLOSE: - dnbd3_blk_fail_all_requests(dev); - result = dnbd3_net_disconnect(dev); - dnbd3_blk_fail_all_requests(dev); - blk_mq_freeze_queue(dev->queue); - set_capacity(dev->disk, 0); - blk_mq_unfreeze_queue(dev->queue); - if (dev->imgname) + if (atomic_cmpxchg(&dev->connection_lock, 0, 1) != 0) { - kfree(dev->imgname); - dev->imgname = NULL; + result = -EBUSY; + break; } + locked = 1; + result = dnbd3_close_device(dev); break; case IOCTL_SWITCH: + if (atomic_cmpxchg(&dev->connection_lock, 0, 1) != 0) + { + result = -EBUSY; + break; + } + locked = 1; if (dev->imgname == NULL) { result = -ENOENT; @@ -278,6 +304,9 @@ static int dnbd3_blk_ioctl(struct block_device *bdev, fmode_t mode, unsigned int break; } + if (locked) + atomic_set(&dev->connection_lock, 0); + cleanup_return: if (msg) kfree(msg); if (imgname) kfree(imgname); @@ -354,7 +383,7 @@ int dnbd3_blk_add_device(dnbd3_device_t *dev, int minor) dev->thread_receive = NULL; dev->thread_discover = NULL; dev->discover = 0; - dev->disconnecting = 0; + atomic_set(&dev->connection_lock, 0); dev->panic = 0; dev->panic_count = 0; dev->reported_size = 0; @@ -432,8 +461,10 @@ out: int dnbd3_blk_del_device(dnbd3_device_t *dev) { + while (atomic_cmpxchg(&dev->connection_lock, 0, 1) != 0) + schedule(); + dnbd3_close_device(dev); dnbd3_sysfs_exit(dev); - dnbd3_net_disconnect(dev); del_gendisk(dev->disk); blk_cleanup_queue(dev->queue); blk_mq_free_tag_set(&dev->tag_set); |