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| author | Simon Rettberg | 2020-07-17 18:19:58 +0200 |
|---|---|---|
| committer | Simon Rettberg | 2020-07-17 18:19:58 +0200 |
| commit | a231e6283e1c79a33d6f3bdf786832f10e355d0c (patch) | |
| tree | a5be40fa9fe93230d06de56ccac3c378f80c3833 /src/kernel/core.c | |
| parent | [KERNEL] After nullptr check, MAYBE RETURN!? (diff) | |
| download | dnbd3-ng-a231e6283e1c79a33d6f3bdf786832f10e355d0c.tar.gz dnbd3-ng-a231e6283e1c79a33d6f3bdf786832f10e355d0c.tar.xz dnbd3-ng-a231e6283e1c79a33d6f3bdf786832f10e355d0c.zip | |
[KERNEL] Trying to get locking under control
Current code doesn't pay much attention to properly locking when
accessing structures that are being used in multiple workers/threads.
Try to fix this, slowly.
Diffstat (limited to 'src/kernel/core.c')
| -rw-r--r-- | src/kernel/core.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/src/kernel/core.c b/src/kernel/core.c index 35ea1ef..8da2b39 100644 --- a/src/kernel/core.c +++ b/src/kernel/core.c @@ -124,6 +124,7 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, switch (cmd) { case IOCTL_OPEN: debug_dev(dev, "ioctl open"); + mutex_lock(&dev->device_lock); if (dev->imgname != NULL) { result = -EBUSY; } else if (imgname == NULL) { @@ -131,7 +132,6 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, } else if (msg == NULL) { result = -EINVAL; } else { - mutex_lock(&dev->device_lock); if (sizeof(msg->host) != sizeof(dnbd3_host_t)) { warn_dev(dev, "odd size bug#1 triggered in ioctl"); } @@ -154,7 +154,6 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, } else { dev->number_connections = msg->number_connections; } - mutex_unlock(&dev->device_lock); result = dnbd3_net_connect(dev); if (result) { @@ -165,10 +164,12 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, } imgname = NULL; } + mutex_unlock(&dev->device_lock); break; case IOCTL_CLOSE: debug_dev(dev, "ioctl close"); + mutex_lock(&dev->device_lock); result = dnbd3_net_disconnect(dev); set_capacity(dev->disk, 0); if (dev->imgname) { @@ -177,6 +178,7 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, } dev->rid = 0; dev->reported_size = 0; + mutex_unlock(&dev->device_lock); break; case IOCTL_SWITCH: @@ -187,6 +189,7 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, case IOCTL_ADD_SRV: case IOCTL_REM_SRV: debug_dev(dev, "ioctl add/rem srv"); + mutex_lock(&dev->device_lock); if (dev->imgname == NULL) { result = -ENOENT; } else if (dev->new_servers_num >= NUMBER_SERVERS) { @@ -194,16 +197,15 @@ static int dnbd3_ioctl(struct block_device *bdev, fmode_t mode, } else if (msg == NULL) { result = -EINVAL; } else { - mutex_lock(&dev->device_lock); memcpy(&dev->new_servers[dev->new_servers_num].host, &msg->host, sizeof(msg->host)); /* 0 = ADD, 1 = REM */ dev->new_servers[dev->new_servers_num].failures = (cmd == IOCTL_ADD_SRV ? 0 : 1); dev->new_servers_num++; - mutex_unlock(&dev->device_lock); result = 0; } + mutex_unlock(&dev->device_lock); break; case BLKFLSBUF: @@ -417,7 +419,7 @@ static void dnbd3_dev_remove(struct dnbd3_device *dev) struct gendisk *disk = dev->disk; struct request_queue *q; - if (dev->connected) { + if (dev->socks) { dnbd3_net_disconnect(dev); } |