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path: root/drivers/block/nbd.c
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Diffstat (limited to 'drivers/block/nbd.c')
-rw-r--r--drivers/block/nbd.c104
1 files changed, 81 insertions, 23 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index d32cd943dff2..929bd255a290 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -106,6 +106,7 @@ struct nbd_device {
struct nbd_config *config;
struct mutex config_lock;
struct gendisk *disk;
+ struct workqueue_struct *recv_workq;
struct list_head list;
struct task_struct *task_recv;
@@ -132,9 +133,10 @@ static struct dentry *nbd_dbg_dir;
#define NBD_MAGIC 0x68797548
+#define NBD_DEF_BLKSIZE 1024
+
static unsigned int nbds_max = 16;
static int max_part = 16;
-static struct workqueue_struct *recv_workqueue;
static int part_shift;
static int nbd_dev_dbg_init(struct nbd_device *nbd);
@@ -226,8 +228,8 @@ static void nbd_put(struct nbd_device *nbd)
if (refcount_dec_and_mutex_lock(&nbd->refs,
&nbd_index_mutex)) {
idr_remove(&nbd_index_idr, nbd->index);
- mutex_unlock(&nbd_index_mutex);
nbd_dev_remove(nbd);
+ mutex_unlock(&nbd_index_mutex);
}
}
@@ -340,8 +342,10 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
}
config = nbd->config;
- if (!mutex_trylock(&cmd->lock))
+ if (!mutex_trylock(&cmd->lock)) {
+ nbd_config_put(nbd);
return BLK_EH_RESET_TIMER;
+ }
if (config->num_connections > 1) {
dev_err_ratelimited(nbd_to_dev(nbd),
@@ -644,6 +648,12 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index)
ret = -ENOENT;
goto out;
}
+ if (cmd->status != BLK_STS_OK) {
+ dev_err(disk_to_dev(nbd->disk), "Command already handled %p\n",
+ req);
+ ret = -ENOENT;
+ goto out;
+ }
if (test_bit(NBD_CMD_REQUEUED, &cmd->flags)) {
dev_err(disk_to_dev(nbd->disk), "Raced with timeout on req %p\n",
req);
@@ -908,6 +918,26 @@ static blk_status_t nbd_queue_rq(struct blk_mq_hw_ctx *hctx,
return ret;
}
+static struct socket *nbd_get_socket(struct nbd_device *nbd, unsigned long fd,
+ int *err)
+{
+ struct socket *sock;
+
+ *err = 0;
+ sock = sockfd_lookup(fd, err);
+ if (!sock)
+ return NULL;
+
+ if (sock->ops->shutdown == sock_no_shutdown) {
+ dev_err(disk_to_dev(nbd->disk), "Unsupported socket: shutdown callout must be supported.\n");
+ *err = -EINVAL;
+ sockfd_put(sock);
+ return NULL;
+ }
+
+ return sock;
+}
+
static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg,
bool netlink)
{
@@ -917,7 +947,7 @@ static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg,
struct nbd_sock *nsock;
int err;
- sock = sockfd_lookup(arg, &err);
+ sock = nbd_get_socket(nbd, arg, &err);
if (!sock)
return err;
@@ -940,14 +970,15 @@ static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg,
sockfd_put(sock);
return -ENOMEM;
}
+
+ config->socks = socks;
+
nsock = kzalloc(sizeof(struct nbd_sock), GFP_KERNEL);
if (!nsock) {
sockfd_put(sock);
return -ENOMEM;
}
- config->socks = socks;
-
nsock->fallback_index = -1;
nsock->dead = false;
mutex_init(&nsock->tx_lock);
@@ -969,7 +1000,7 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg)
int i;
int err;
- sock = sockfd_lookup(arg, &err);
+ sock = nbd_get_socket(nbd, arg, &err);
if (!sock)
return err;
@@ -1011,7 +1042,7 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg)
/* We take the tx_mutex in an error path in the recv_work, so we
* need to queue_work outside of the tx_mutex.
*/
- queue_work(recv_workqueue, &args->work);
+ queue_work(nbd->recv_workq, &args->work);
atomic_inc(&config->live_connections);
wake_up(&config->conn_wait);
@@ -1116,6 +1147,10 @@ static void nbd_config_put(struct nbd_device *nbd)
kfree(nbd->config);
nbd->config = NULL;
+ if (nbd->recv_workq)
+ destroy_workqueue(nbd->recv_workq);
+ nbd->recv_workq = NULL;
+
nbd->tag_set.timeout = 0;
queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue);
@@ -1141,6 +1176,14 @@ static int nbd_start_device(struct nbd_device *nbd)
return -EINVAL;
}
+ nbd->recv_workq = alloc_workqueue("knbd%d-recv",
+ WQ_MEM_RECLAIM | WQ_HIGHPRI |
+ WQ_UNBOUND, 0, nbd->index);
+ if (!nbd->recv_workq) {
+ dev_err(disk_to_dev(nbd->disk), "Could not allocate knbd recv work queue.\n");
+ return -ENOMEM;
+ }
+
blk_mq_update_nr_hw_queues(&nbd->tag_set, config->num_connections);
nbd->task_recv = current;
@@ -1171,7 +1214,7 @@ static int nbd_start_device(struct nbd_device *nbd)
INIT_WORK(&args->work, recv_work);
args->nbd = nbd;
args->index = i;
- queue_work(recv_workqueue, &args->work);
+ queue_work(nbd->recv_workq, &args->work);
}
nbd_size_update(nbd);
return error;
@@ -1191,8 +1234,10 @@ static int nbd_start_device_ioctl(struct nbd_device *nbd, struct block_device *b
mutex_unlock(&nbd->config_lock);
ret = wait_event_interruptible(config->recv_wq,
atomic_read(&config->recv_threads) == 0);
- if (ret)
+ if (ret) {
sock_shutdown(nbd);
+ flush_workqueue(nbd->recv_workq);
+ }
mutex_lock(&nbd->config_lock);
bd_set_size(bdev, 0);
/* user requested, ignore socket errors */
@@ -1207,13 +1252,21 @@ static void nbd_clear_sock_ioctl(struct nbd_device *nbd,
struct block_device *bdev)
{
sock_shutdown(nbd);
- kill_bdev(bdev);
+ __invalidate_device(bdev, true);
nbd_bdev_reset(bdev);
if (test_and_clear_bit(NBD_HAS_CONFIG_REF,
&nbd->config->runtime_flags))
nbd_config_put(nbd);
}
+static bool nbd_is_valid_blksize(unsigned long blksize)
+{
+ if (!blksize || !is_power_of_2(blksize) || blksize < 512 ||
+ blksize > PAGE_SIZE)
+ return false;
+ return true;
+}
+
/* Must be called with config_lock held */
static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
unsigned int cmd, unsigned long arg)
@@ -1229,8 +1282,9 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
case NBD_SET_SOCK:
return nbd_add_socket(nbd, arg, false);
case NBD_SET_BLKSIZE:
- if (!arg || !is_power_of_2(arg) || arg < 512 ||
- arg > PAGE_SIZE)
+ if (!arg)
+ arg = NBD_DEF_BLKSIZE;
+ if (!nbd_is_valid_blksize(arg))
return -EINVAL;
nbd_size_set(nbd, arg,
div_s64(config->bytesize, arg));
@@ -1310,7 +1364,7 @@ static struct nbd_config *nbd_alloc_config(void)
atomic_set(&config->recv_threads, 0);
init_waitqueue_head(&config->recv_wq);
init_waitqueue_head(&config->conn_wait);
- config->blksize = 1024;
+ config->blksize = NBD_DEF_BLKSIZE;
atomic_set(&config->live_connections, 0);
try_module_get(THIS_MODULE);
return config;
@@ -1742,6 +1796,12 @@ again:
if (info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]) {
u64 bsize =
nla_get_u64(info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]);
+ if (!bsize)
+ bsize = NBD_DEF_BLKSIZE;
+ if (!nbd_is_valid_blksize(bsize)) {
+ ret = -EINVAL;
+ goto out;
+ }
nbd_size_set(nbd, bsize, div64_u64(config->bytesize, bsize));
}
if (info->attrs[NBD_ATTR_TIMEOUT]) {
@@ -1817,6 +1877,12 @@ static void nbd_disconnect_and_put(struct nbd_device *nbd)
mutex_lock(&nbd->config_lock);
nbd_disconnect(nbd);
mutex_unlock(&nbd->config_lock);
+ /*
+ * Make sure recv thread has finished, so it does not drop the last
+ * config ref and try to destroy the workqueue from inside the work
+ * queue.
+ */
+ flush_workqueue(nbd->recv_workq);
if (test_and_clear_bit(NBD_HAS_CONFIG_REF,
&nbd->config->runtime_flags))
nbd_config_put(nbd);
@@ -2197,19 +2263,12 @@ static int __init nbd_init(void)
if (nbds_max > 1UL << (MINORBITS - part_shift))
return -EINVAL;
- recv_workqueue = alloc_workqueue("knbd-recv",
- WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
- if (!recv_workqueue)
- return -ENOMEM;
- if (register_blkdev(NBD_MAJOR, "nbd")) {
- destroy_workqueue(recv_workqueue);
+ if (register_blkdev(NBD_MAJOR, "nbd"))
return -EIO;
- }
if (genl_register_family(&nbd_genl_family)) {
unregister_blkdev(NBD_MAJOR, "nbd");
- destroy_workqueue(recv_workqueue);
return -EINVAL;
}
nbd_dbg_init();
@@ -2251,7 +2310,6 @@ static void __exit nbd_cleanup(void)
idr_destroy(&nbd_index_idr);
genl_unregister_family(&nbd_genl_family);
- destroy_workqueue(recv_workqueue);
unregister_blkdev(NBD_MAJOR, "nbd");
}