fix nbd makefile

2 files changed, 1 insertions, 1137 deletions

diff --git a/builder/dnbd3-rootfs/binaries/nbd/Makefile b/builder/dnbd3-rootfs/binaries/nbd/Makefile
index ca0423f5..4dd501c3 100644..100755
--- a/builder/dnbd3-rootfs/binaries/nbd/Makefile
+++ b/builder/dnbd3-rootfs/binaries/nbd/Makefile
@@ -12,4 +12,4 @@ clean:
 	make --directory /lib/modules/$(shell uname -r)/build M=$(PWD) clean
 
 update:
-	curl --location --remote-name https://raw.githubusercontent.com/torvalds/linux/master/drivers/block/nbd.c
+	curl --location --remote-name "https://raw.githubusercontent.com/torvalds/linux/v$(uname --kernel-release | cut --delimiter='.' --fields=1-2)/drivers/block/nbd.c"
diff --git a/builder/dnbd3-rootfs/binaries/nbd/nbd.c b/builder/dnbd3-rootfs/binaries/nbd/nbd.c
deleted file mode 100644
index 1b876233..00000000
--- a/builder/dnbd3-rootfs/binaries/nbd/nbd.c
+++ /dev/null
@@ -1,1136 +0,0 @@
-/*
- * Network block device - make block devices work over TCP
- *
- * Note that you can not swap over this thing, yet. Seems to work but
- * deadlocks sometimes - you can not swap over TCP in general.
- * 
- * Copyright 1997-2000, 2008 Pavel Machek <pavel@ucw.cz>
- * Parts copyright 2001 Steven Whitehouse <steve@chygwyn.com>
- *
- * This file is released under GPLv2 or later.
- *
- * (part of code stolen from loop.c)
- */
-
-#include <linux/major.h>
-
-#include <linux/blkdev.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/sched.h>
-#include <linux/fs.h>
-#include <linux/bio.h>
-#include <linux/stat.h>
-#include <linux/errno.h>
-#include <linux/file.h>
-#include <linux/ioctl.h>
-#include <linux/mutex.h>
-#include <linux/compiler.h>
-#include <linux/err.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <net/sock.h>
-#include <linux/net.h>
-#include <linux/kthread.h>
-#include <linux/types.h>
-#include <linux/debugfs.h>
-
-#include <asm/uaccess.h>
-#include <asm/types.h>
-
-#include <linux/nbd.h>
-
-struct nbd_device {
-	u32 flags;
-	struct socket * sock;	/* If == NULL, device is not ready, yet	*/
-	int magic;
-
-	spinlock_t queue_lock;
-	struct list_head queue_head;	/* Requests waiting result */
-	struct request *active_req;
-	wait_queue_head_t active_wq;
-	struct list_head waiting_queue;	/* Requests to be sent */
-	wait_queue_head_t waiting_wq;
-
-	struct mutex tx_lock;
-	struct gendisk *disk;
-	int blksize;
-	loff_t bytesize;
-	int xmit_timeout;
-	bool disconnect; /* a disconnect has been requested by user */
-
-	struct timer_list timeout_timer;
-	spinlock_t tasks_lock;
-	struct task_struct *task_recv;
-	struct task_struct *task_send;
-
-#if IS_ENABLED(CONFIG_DEBUG_FS)
-	struct dentry *dbg_dir;
-#endif
-};
-
-#if IS_ENABLED(CONFIG_DEBUG_FS)
-static struct dentry *nbd_dbg_dir;
-#endif
-
-#define nbd_name(nbd) ((nbd)->disk->disk_name)
-
-#define NBD_MAGIC 0x68797548
-
-static unsigned int nbds_max = 16;
-static struct nbd_device *nbd_dev;
-static int max_part;
-
-/*
- * Use just one lock (or at most 1 per NIC). Two arguments for this:
- * 1. Each NIC is essentially a synchronization point for all servers
- *    accessed through that NIC so there's no need to have more locks
- *    than NICs anyway.
- * 2. More locks lead to more "Dirty cache line bouncing" which will slow
- *    down each lock to the point where they're actually slower than just
- *    a single lock.
- * Thanks go to Jens Axboe and Al Viro for their LKML emails explaining this!
- */
-static DEFINE_SPINLOCK(nbd_lock);
-
-static inline struct device *nbd_to_dev(struct nbd_device *nbd)
-{
-	return disk_to_dev(nbd->disk);
-}
-
-static const char *nbdcmd_to_ascii(int cmd)
-{
-	switch (cmd) {
-	case  NBD_CMD_READ: return "read";
-	case NBD_CMD_WRITE: return "write";
-	case  NBD_CMD_DISC: return "disconnect";
-	case NBD_CMD_FLUSH: return "flush";
-	case  NBD_CMD_TRIM: return "trim/discard";
-	}
-	return "invalid";
-}
-
-static void nbd_end_request(struct nbd_device *nbd, struct request *req)
-{
-	int error = req->errors ? -EIO : 0;
-	struct request_queue *q = req->q;
-	unsigned long flags;
-
-	dev_dbg(nbd_to_dev(nbd), "request %p: %s\n", req,
-		error ? "failed" : "done");
-
-	spin_lock_irqsave(q->queue_lock, flags);
-	__blk_end_request_all(req, error);
-	spin_unlock_irqrestore(q->queue_lock, flags);
-}
-
-/*
- * Forcibly shutdown the socket causing all listeners to error
- */
-static void sock_shutdown(struct nbd_device *nbd)
-{
-	if (!nbd->sock)
-		return;
-
-	dev_warn(disk_to_dev(nbd->disk), "shutting down socket\n");
-	kernel_sock_shutdown(nbd->sock, SHUT_RDWR);
-	nbd->sock = NULL;
-	del_timer_sync(&nbd->timeout_timer);
-}
-
-static void nbd_xmit_timeout(unsigned long arg)
-{
-	struct nbd_device *nbd = (struct nbd_device *)arg;
-	unsigned long flags;
-
-	if (list_empty(&nbd->queue_head))
-		return;
-
-	nbd->disconnect = true;
-
-	spin_lock_irqsave(&nbd->tasks_lock, flags);
-
-	if (nbd->task_recv)
-		force_sig(SIGKILL, nbd->task_recv);
-
-	if (nbd->task_send)
-		force_sig(SIGKILL, nbd->task_send);
-
-	spin_unlock_irqrestore(&nbd->tasks_lock, flags);
-
-	dev_err(nbd_to_dev(nbd), "Connection timed out, killed receiver and sender, shutting down connection\n");
-}
-
-/*
- *  Send or receive packet.
- */
-static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size,
-		int msg_flags)
-{
-	struct socket *sock = nbd->sock;
-	int result;
-	struct msghdr msg;
-	struct kvec iov;
-	sigset_t blocked, oldset;
-	unsigned long pflags = current->flags;
-
-	if (unlikely(!sock)) {
-		dev_err(disk_to_dev(nbd->disk),
-			"Attempted %s on closed socket in sock_xmit\n",
-			(send ? "send" : "recv"));
-		return -EINVAL;
-	}
-
-	/* Allow interception of SIGKILL only
-	 * Don't allow other signals to interrupt the transmission */
-	siginitsetinv(&blocked, sigmask(SIGKILL));
-	sigprocmask(SIG_SETMASK, &blocked, &oldset);
-
-	current->flags |= PF_MEMALLOC;
-	do {
-		sock->sk->sk_allocation = GFP_NOIO | __GFP_MEMALLOC;
-		iov.iov_base = buf;
-		iov.iov_len = size;
-		msg.msg_name = NULL;
-		msg.msg_namelen = 0;
-		msg.msg_control = NULL;
-		msg.msg_controllen = 0;
-		msg.msg_flags = msg_flags | MSG_NOSIGNAL;
-
-		if (send)
-			result = kernel_sendmsg(sock, &msg, &iov, 1, size);
-		else
-			result = kernel_recvmsg(sock, &msg, &iov, 1, size,
-						msg.msg_flags);
-
-		if (result <= 0) {
-			if (result == 0)
-				result = -EPIPE; /* short read */
-			break;
-		}
-		size -= result;
-		buf += result;
-	} while (size > 0);
-
-	sigprocmask(SIG_SETMASK, &oldset, NULL);
-	tsk_restore_flags(current, pflags, PF_MEMALLOC);
-
-	if (!send && nbd->xmit_timeout)
-		mod_timer(&nbd->timeout_timer, jiffies + nbd->xmit_timeout);
-
-	return result;
-}
-
-static inline int sock_send_bvec(struct nbd_device *nbd, struct bio_vec *bvec,
-		int flags)
-{
-	int result;
-	void *kaddr = kmap(bvec->bv_page);
-	result = sock_xmit(nbd, 1, kaddr + bvec->bv_offset,
-			   bvec->bv_len, flags);
-	kunmap(bvec->bv_page);
-	return result;
-}
-
-/* always call with the tx_lock held */
-static int nbd_send_req(struct nbd_device *nbd, struct request *req)
-{
-	int result, flags;
-	struct nbd_request request;
-	unsigned long size = blk_rq_bytes(req);
-	u32 type;
-
-	if (req->cmd_type == REQ_TYPE_DRV_PRIV)
-		type = NBD_CMD_DISC;
-	else if (req->cmd_flags & REQ_DISCARD)
-		type = NBD_CMD_TRIM;
-	else if (req->cmd_flags & REQ_FLUSH)
-		type = NBD_CMD_FLUSH;
-	else if (rq_data_dir(req) == WRITE)
-		type = NBD_CMD_WRITE;
-	else
-		type = NBD_CMD_READ;
-
-	memset(&request, 0, sizeof(request));
-	request.magic = htonl(NBD_REQUEST_MAGIC);
-	request.type = htonl(type);
-	if (type != NBD_CMD_FLUSH && type != NBD_CMD_DISC) {
-		request.from = cpu_to_be64((u64)blk_rq_pos(req) << 9);
-		request.len = htonl(size);
-	}
-	memcpy(request.handle, &req, sizeof(req));
-
-	dev_dbg(nbd_to_dev(nbd), "request %p: sending control (%s@%llu,%uB)\n",
-		req, nbdcmd_to_ascii(type),
-		(unsigned long long)blk_rq_pos(req) << 9, blk_rq_bytes(req));
-	result = sock_xmit(nbd, 1, &request, sizeof(request),
-			(type == NBD_CMD_WRITE) ? MSG_MORE : 0);
-	if (result <= 0) {
-		dev_err(disk_to_dev(nbd->disk),
-			"Send control failed (result %d)\n", result);
-		return -EIO;
-	}
-
-	if (type == NBD_CMD_WRITE) {
-		struct req_iterator iter;
-		struct bio_vec bvec;
-		/*
-		 * we are really probing at internals to determine
-		 * whether to set MSG_MORE or not...
-		 */
-		rq_for_each_segment(bvec, req, iter) {
-			flags = 0;
-			if (!rq_iter_last(bvec, iter))
-				flags = MSG_MORE;
-			dev_dbg(nbd_to_dev(nbd), "request %p: sending %d bytes data\n",
-				req, bvec.bv_len);
-			result = sock_send_bvec(nbd, &bvec, flags);
-			if (result <= 0) {
-				dev_err(disk_to_dev(nbd->disk),
-					"Send data failed (result %d)\n",
-					result);
-				return -EIO;
-			}
-		}
-	}
-	return 0;
-}
-
-static struct request *nbd_find_request(struct nbd_device *nbd,
-					struct request *xreq)
-{
-	struct request *req, *tmp;
-	int err;
-
-	err = wait_event_interruptible(nbd->active_wq, nbd->active_req != xreq);
-	if (unlikely(err))
-		return ERR_PTR(err);
-
-	spin_lock(&nbd->queue_lock);
-	list_for_each_entry_safe(req, tmp, &nbd->queue_head, queuelist) {
-		if (req != xreq)
-			continue;
-		list_del_init(&req->queuelist);
-		spin_unlock(&nbd->queue_lock);
-		return req;
-	}
-	spin_unlock(&nbd->queue_lock);
-
-	return ERR_PTR(-ENOENT);
-}
-
-static inline int sock_recv_bvec(struct nbd_device *nbd, struct bio_vec *bvec)
-{
-	int result;
-	void *kaddr = kmap(bvec->bv_page);
-	result = sock_xmit(nbd, 0, kaddr + bvec->bv_offset, bvec->bv_len,
-			MSG_WAITALL);
-	kunmap(bvec->bv_page);
-	return result;
-}
-
-/* NULL returned = something went wrong, inform userspace */
-static struct request *nbd_read_stat(struct nbd_device *nbd)
-{
-	int result;
-	struct nbd_reply reply;
-	struct request *req;
-
-	reply.magic = 0;
-	result = sock_xmit(nbd, 0, &reply, sizeof(reply), MSG_WAITALL);
-	if (result <= 0) {
-		dev_err(disk_to_dev(nbd->disk),
-			"Receive control failed (result %d)\n", result);
-		return ERR_PTR(result);
-	}
-
-	if (ntohl(reply.magic) != NBD_REPLY_MAGIC) {
-		dev_err(disk_to_dev(nbd->disk), "Wrong magic (0x%lx)\n",
-				(unsigned long)ntohl(reply.magic));
-		return ERR_PTR(-EPROTO);
-	}
-
-	req = nbd_find_request(nbd, *(struct request **)reply.handle);
-	if (IS_ERR(req)) {
-		result = PTR_ERR(req);
-		if (result != -ENOENT)
-			return ERR_PTR(result);
-
-		dev_err(disk_to_dev(nbd->disk), "Unexpected reply (%p)\n",
-			reply.handle);
-		return ERR_PTR(-EBADR);
-	}
-
-	if (ntohl(reply.error)) {
-		dev_err(disk_to_dev(nbd->disk), "Other side returned error (%d)\n",
-			ntohl(reply.error));
-		req->errors++;
-		return req;
-	}
-
-	dev_dbg(nbd_to_dev(nbd), "request %p: got reply\n", req);
-	if (rq_data_dir(req) != WRITE) {
-		struct req_iterator iter;
-		struct bio_vec bvec;
-
-		rq_for_each_segment(bvec, req, iter) {
-			result = sock_recv_bvec(nbd, &bvec);
-			if (result <= 0) {
-				dev_err(disk_to_dev(nbd->disk), "Receive data failed (result %d)\n",
-					result);
-				req->errors++;
-				return req;
-			}
-			dev_dbg(nbd_to_dev(nbd), "request %p: got %d bytes data\n",
-				req, bvec.bv_len);
-		}
-	}
-	return req;
-}
-
-static ssize_t pid_show(struct device *dev,
-			struct device_attribute *attr, char *buf)
-{
-	struct gendisk *disk = dev_to_disk(dev);
-	struct nbd_device *nbd = (struct nbd_device *)disk->private_data;
-
-	return sprintf(buf, "%d\n", task_pid_nr(nbd->task_recv));
-}
-
-static struct device_attribute pid_attr = {
-	.attr = { .name = "pid", .mode = S_IRUGO},
-	.show = pid_show,
-};
-
-static int nbd_thread_recv(struct nbd_device *nbd)
-{
-	struct request *req;
-	int ret;
-	unsigned long flags;
-
-	BUG_ON(nbd->magic != NBD_MAGIC);
-
-	sk_set_memalloc(nbd->sock->sk);
-
-	spin_lock_irqsave(&nbd->tasks_lock, flags);
-	nbd->task_recv = current;
-	spin_unlock_irqrestore(&nbd->tasks_lock, flags);
-
-	ret = device_create_file(disk_to_dev(nbd->disk), &pid_attr);
-	if (ret) {
-		dev_err(disk_to_dev(nbd->disk), "device_create_file failed!\n");
-
-		spin_lock_irqsave(&nbd->tasks_lock, flags);
-		nbd->task_recv = NULL;
-		spin_unlock_irqrestore(&nbd->tasks_lock, flags);
-
-		return ret;
-	}
-
-	while (1) {
-		req = nbd_read_stat(nbd);
-		if (IS_ERR(req)) {
-			ret = PTR_ERR(req);
-			break;
-		}
-
-		nbd_end_request(nbd, req);
-	}
-
-	device_remove_file(disk_to_dev(nbd->disk), &pid_attr);
-
-	spin_lock_irqsave(&nbd->tasks_lock, flags);
-	nbd->task_recv = NULL;
-	spin_unlock_irqrestore(&nbd->tasks_lock, flags);
-
-	if (signal_pending(current)) {
-		siginfo_t info;
-
-		ret = dequeue_signal_lock(current, &current->blocked, &info);
-		dev_warn(nbd_to_dev(nbd), "pid %d, %s, got signal %d\n",
-			 task_pid_nr(current), current->comm, ret);
-		mutex_lock(&nbd->tx_lock);
-		sock_shutdown(nbd);
-		mutex_unlock(&nbd->tx_lock);
-		ret = -ETIMEDOUT;
-	}
-
-	return ret;
-}
-
-static void nbd_clear_que(struct nbd_device *nbd)
-{
-	struct request *req;
-
-	BUG_ON(nbd->magic != NBD_MAGIC);
-
-	/*
-	 * Because we have set nbd->sock to NULL under the tx_lock, all
-	 * modifications to the list must have completed by now.  For
-	 * the same reason, the active_req must be NULL.
-	 *
-	 * As a consequence, we don't need to take the spin lock while
-	 * purging the list here.
-	 */
-	BUG_ON(nbd->sock);
-	BUG_ON(nbd->active_req);
-
-	while (!list_empty(&nbd->queue_head)) {
-		req = list_entry(nbd->queue_head.next, struct request,
-				 queuelist);
-		list_del_init(&req->queuelist);
-		req->errors++;
-		nbd_end_request(nbd, req);
-	}
-
-	while (!list_empty(&nbd->waiting_queue)) {
-		req = list_entry(nbd->waiting_queue.next, struct request,
-				 queuelist);
-		list_del_init(&req->queuelist);
-		req->errors++;
-		nbd_end_request(nbd, req);
-	}
-	dev_dbg(disk_to_dev(nbd->disk), "queue cleared\n");
-}
-
-
-static void nbd_handle_req(struct nbd_device *nbd, struct request *req)
-{
-	if (req->cmd_type != REQ_TYPE_FS)
-		goto error_out;
-
-	if (rq_data_dir(req) == WRITE &&
-	    (nbd->flags & NBD_FLAG_READ_ONLY)) {
-		dev_err(disk_to_dev(nbd->disk),
-			"Write on read-only\n");
-		goto error_out;
-	}
-
-	req->errors = 0;
-
-	mutex_lock(&nbd->tx_lock);
-	if (unlikely(!nbd->sock)) {
-		mutex_unlock(&nbd->tx_lock);
-		dev_err(disk_to_dev(nbd->disk),
-			"Attempted send on closed socket\n");
-		goto error_out;
-	}
-
-	nbd->active_req = req;
-
-	if (nbd->xmit_timeout && list_empty_careful(&nbd->queue_head))
-		mod_timer(&nbd->timeout_timer, jiffies + nbd->xmit_timeout);
-
-	if (nbd_send_req(nbd, req) != 0) {
-		dev_err(disk_to_dev(nbd->disk), "Request send failed\n");
-		req->errors++;
-		nbd_end_request(nbd, req);
-	} else {
-		spin_lock(&nbd->queue_lock);
-		list_add_tail(&req->queuelist, &nbd->queue_head);
-		spin_unlock(&nbd->queue_lock);
-	}
-
-	nbd->active_req = NULL;
-	mutex_unlock(&nbd->tx_lock);
-	wake_up_all(&nbd->active_wq);
-
-	return;
-
-error_out:
-	req->errors++;
-	nbd_end_request(nbd, req);
-}
-
-static int nbd_thread_send(void *data)
-{
-	struct nbd_device *nbd = data;
-	struct request *req;
-	unsigned long flags;
-
-	spin_lock_irqsave(&nbd->tasks_lock, flags);
-	nbd->task_send = current;
-	spin_unlock_irqrestore(&nbd->tasks_lock, flags);
-
-	set_user_nice(current, MIN_NICE);
-	while (!kthread_should_stop() || !list_empty(&nbd->waiting_queue)) {
-		/* wait for something to do */
-		wait_event_interruptible(nbd->waiting_wq,
-					 kthread_should_stop() ||
-					 !list_empty(&nbd->waiting_queue));
-
-		if (signal_pending(current)) {
-			siginfo_t info;
-			int ret;
-
-			ret = dequeue_signal_lock(current, &current->blocked,
-						  &info);
-			dev_warn(nbd_to_dev(nbd), "pid %d, %s, got signal %d\n",
-				 task_pid_nr(current), current->comm, ret);
-			mutex_lock(&nbd->tx_lock);
-			sock_shutdown(nbd);
-			mutex_unlock(&nbd->tx_lock);
-			break;
-		}
-
-		/* extract request */
-		if (list_empty(&nbd->waiting_queue))
-			continue;
-
-		spin_lock_irq(&nbd->queue_lock);
-		req = list_entry(nbd->waiting_queue.next, struct request,
-				 queuelist);
-		list_del_init(&req->queuelist);
-		spin_unlock_irq(&nbd->queue_lock);
-
-		/* handle request */
-		nbd_handle_req(nbd, req);
-	}
-
-	spin_lock_irqsave(&nbd->tasks_lock, flags);
-	nbd->task_send = NULL;
-	spin_unlock_irqrestore(&nbd->tasks_lock, flags);
-
-	/* Clear maybe pending signals */
-	if (signal_pending(current)) {
-		siginfo_t info;
-		dequeue_signal_lock(current, &current->blocked, &info);
-	}
-
-	return 0;
-}
-
-/*
- * We always wait for result of write, for now. It would be nice to make it optional
- * in future
- * if ((rq_data_dir(req) == WRITE) && (nbd->flags & NBD_WRITE_NOCHK))
- *   { printk( "Warning: Ignoring result!\n"); nbd_end_request( req ); }
- */
-
-static void nbd_request_handler(struct request_queue *q)
-		__releases(q->queue_lock) __acquires(q->queue_lock)
-{
-	struct request *req;
-	
-	while ((req = blk_fetch_request(q)) != NULL) {
-		struct nbd_device *nbd;
-
-		spin_unlock_irq(q->queue_lock);
-
-		nbd = req->rq_disk->private_data;
-
-		BUG_ON(nbd->magic != NBD_MAGIC);
-
-		dev_dbg(nbd_to_dev(nbd), "request %p: dequeued (flags=%x)\n",
-			req, req->cmd_type);
-
-		if (unlikely(!nbd->sock)) {
-			dev_err(disk_to_dev(nbd->disk),
-				"Attempted send on closed socket\n");
-			req->errors++;
-			nbd_end_request(nbd, req);
-			spin_lock_irq(q->queue_lock);
-			continue;
-		}
-
-		spin_lock_irq(&nbd->queue_lock);
-		list_add_tail(&req->queuelist, &nbd->waiting_queue);
-		spin_unlock_irq(&nbd->queue_lock);
-
-		wake_up(&nbd->waiting_wq);
-
-		spin_lock_irq(q->queue_lock);
-	}
-}
-
-static int nbd_dev_dbg_init(struct nbd_device *nbd);
-static void nbd_dev_dbg_close(struct nbd_device *nbd);
-
-/* Must be called with tx_lock held */
-
-static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
-		       unsigned int cmd, unsigned long arg)
-{
-	switch (cmd) {
-	case NBD_DISCONNECT: {
-		struct request sreq;
-
-		dev_info(disk_to_dev(nbd->disk), "NBD_DISCONNECT\n");
-		if (!nbd->sock)
-			return -EINVAL;
-
-		mutex_unlock(&nbd->tx_lock);
-		fsync_bdev(bdev);
-		mutex_lock(&nbd->tx_lock);
-		blk_rq_init(NULL, &sreq);
-		sreq.cmd_type = REQ_TYPE_DRV_PRIV;
-
-		/* Check again after getting mutex back.  */
-		if (!nbd->sock)
-			return -EINVAL;
-
-		nbd->disconnect = true;
-
-		nbd_send_req(nbd, &sreq);
-		return 0;
-	}
- 
-	case NBD_CLEAR_SOCK: {
-		struct socket *sock = nbd->sock;
-		nbd->sock = NULL;
-		nbd_clear_que(nbd);
-		BUG_ON(!list_empty(&nbd->queue_head));
-		BUG_ON(!list_empty(&nbd->waiting_queue));
-		kill_bdev(bdev);
-		if (sock)
-			sockfd_put(sock);
-		return 0;
-	}
-
-	case NBD_SET_SOCK: {
-		struct socket *sock;
-		int err;
-		if (nbd->sock)
-			return -EBUSY;
-		sock = sockfd_lookup(arg, &err);
-		if (sock) {
-			nbd->sock = sock;
-			if (max_part > 0)
-				bdev->bd_invalidated = 1;
-			nbd->disconnect = false; /* we're connected now */
-			return 0;
-		}
-		return -EINVAL;
-	}
-
-	case NBD_SET_BLKSIZE:
-		nbd->blksize = arg;
-		nbd->bytesize &= ~(nbd->blksize-1);
-		bdev->bd_inode->i_size = nbd->bytesize;
-		set_blocksize(bdev, nbd->blksize);
-		set_capacity(nbd->disk, nbd->bytesize >> 9);
-		return 0;
-
-	case NBD_SET_SIZE:
-		nbd->bytesize = arg & ~(nbd->blksize-1);
-		bdev->bd_inode->i_size = nbd->bytesize;
-		set_blocksize(bdev, nbd->blksize);
-		set_capacity(nbd->disk, nbd->bytesize >> 9);
-		return 0;
-
-	case NBD_SET_TIMEOUT:
-		nbd->xmit_timeout = arg * HZ;
-		if (arg)
-			mod_timer(&nbd->timeout_timer,
-				  jiffies + nbd->xmit_timeout);
-		else
-			del_timer_sync(&nbd->timeout_timer);
-
-		return 0;
-
-	case NBD_SET_FLAGS:
-		nbd->flags = arg;
-		return 0;
-
-	case NBD_SET_SIZE_BLOCKS:
-		nbd->bytesize = ((u64) arg) * nbd->blksize;
-		bdev->bd_inode->i_size = nbd->bytesize;
-		set_blocksize(bdev, nbd->blksize);
-		set_capacity(nbd->disk, nbd->bytesize >> 9);
-		return 0;
-
-	case NBD_DO_IT: {
-		struct task_struct *thread;
-		struct socket *sock;
-		int error;
-
-		if (nbd->task_recv)
-			return -EBUSY;
-		if (!nbd->sock)
-			return -EINVAL;
-
-		mutex_unlock(&nbd->tx_lock);
-
-		if (nbd->flags & NBD_FLAG_READ_ONLY)
-			set_device_ro(bdev, true);
-		if (nbd->flags & NBD_FLAG_SEND_TRIM)
-			queue_flag_set_unlocked(QUEUE_FLAG_DISCARD,
-				nbd->disk->queue);
-		if (nbd->flags & NBD_FLAG_SEND_FLUSH)
-			blk_queue_flush(nbd->disk->queue, REQ_FLUSH);
-		else
-			blk_queue_flush(nbd->disk->queue, 0);
-
-		thread = kthread_run(nbd_thread_send, nbd, "%s",
-				     nbd_name(nbd));
-		if (IS_ERR(thread)) {
-			mutex_lock(&nbd->tx_lock);
-			return PTR_ERR(thread);
-		}
-
-		nbd_dev_dbg_init(nbd);
-		error = nbd_thread_recv(nbd);
-		nbd_dev_dbg_close(nbd);
-		kthread_stop(thread);
-
-		mutex_lock(&nbd->tx_lock);
-
-		sock_shutdown(nbd);
-		sock = nbd->sock;
-		nbd->sock = NULL;
-		nbd_clear_que(nbd);
-		kill_bdev(bdev);
-		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue);
-		set_device_ro(bdev, false);
-		if (sock)
-			sockfd_put(sock);
-		nbd->flags = 0;
-		nbd->bytesize = 0;
-		bdev->bd_inode->i_size = 0;
-		set_capacity(nbd->disk, 0);
-		if (max_part > 0)
-			blkdev_reread_part(bdev);
-		if (nbd->disconnect) /* user requested, ignore socket errors */
-			return 0;
-		return error;
-	}
-
-	case NBD_CLEAR_QUE:
-		/*
-		 * This is for compatibility only.  The queue is always cleared
-		 * by NBD_DO_IT or NBD_CLEAR_SOCK.
-		 */
-		return 0;
-
-	case NBD_PRINT_DEBUG:
-		dev_info(disk_to_dev(nbd->disk),
-			"next = %p, prev = %p, head = %p\n",
-			nbd->queue_head.next, nbd->queue_head.prev,
-			&nbd->queue_head);
-		return 0;
-	}
-	return -ENOTTY;
-}
-
-static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
-		     unsigned int cmd, unsigned long arg)
-{
-	struct nbd_device *nbd = bdev->bd_disk->private_data;
-	int error;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
-	BUG_ON(nbd->magic != NBD_MAGIC);
-
-	mutex_lock(&nbd->tx_lock);
-	error = __nbd_ioctl(bdev, nbd, cmd, arg);
-	mutex_unlock(&nbd->tx_lock);
-
-	return error;
-}
-
-static const struct block_device_operations nbd_fops =
-{
-	.owner =	THIS_MODULE,
-	.ioctl =	nbd_ioctl,
-};
-
-#if IS_ENABLED(CONFIG_DEBUG_FS)
-
-static int nbd_dbg_tasks_show(struct seq_file *s, void *unused)
-{
-	struct nbd_device *nbd = s->private;
-
-	if (nbd->task_recv)
-		seq_printf(s, "recv: %d\n", task_pid_nr(nbd->task_recv));
-	if (nbd->task_send)
-		seq_printf(s, "send: %d\n", task_pid_nr(nbd->task_send));
-
-	return 0;
-}
-
-static int nbd_dbg_tasks_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, nbd_dbg_tasks_show, inode->i_private);
-}
-
-static const struct file_operations nbd_dbg_tasks_ops = {
-	.open = nbd_dbg_tasks_open,
-	.read = seq_read,
-	.llseek = seq_lseek,
-	.release = single_release,
-};
-
-static int nbd_dbg_flags_show(struct seq_file *s, void *unused)
-{
-	struct nbd_device *nbd = s->private;
-	u32 flags = nbd->flags;
-
-	seq_printf(s, "Hex: 0x%08x\n\n", flags);
-
-	seq_puts(s, "Known flags:\n");
-
-	if (flags & NBD_FLAG_HAS_FLAGS)
-		seq_puts(s, "NBD_FLAG_HAS_FLAGS\n");
-	if (flags & NBD_FLAG_READ_ONLY)
-		seq_puts(s, "NBD_FLAG_READ_ONLY\n");
-	if (flags & NBD_FLAG_SEND_FLUSH)
-		seq_puts(s, "NBD_FLAG_SEND_FLUSH\n");
-	if (flags & NBD_FLAG_SEND_TRIM)
-		seq_puts(s, "NBD_FLAG_SEND_TRIM\n");
-
-	return 0;
-}
-
-static int nbd_dbg_flags_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, nbd_dbg_flags_show, inode->i_private);
-}
-
-static const struct file_operations nbd_dbg_flags_ops = {
-	.open = nbd_dbg_flags_open,
-	.read = seq_read,
-	.llseek = seq_lseek,
-	.release = single_release,
-};
-
-static int nbd_dev_dbg_init(struct nbd_device *nbd)
-{
-	struct dentry *dir;
-	struct dentry *f;
-
-	dir = debugfs_create_dir(nbd_name(nbd), nbd_dbg_dir);
-	if (IS_ERR_OR_NULL(dir)) {
-		dev_err(nbd_to_dev(nbd), "Failed to create debugfs dir for '%s' (%ld)\n",
-			nbd_name(nbd), PTR_ERR(dir));
-		return PTR_ERR(dir);
-	}
-	nbd->dbg_dir = dir;
-
-	f = debugfs_create_file("tasks", 0444, dir, nbd, &nbd_dbg_tasks_ops);
-	if (IS_ERR_OR_NULL(f)) {
-		dev_err(nbd_to_dev(nbd), "Failed to create debugfs file 'tasks', %ld\n",
-			PTR_ERR(f));
-		return PTR_ERR(f);
-	}
-
-	f = debugfs_create_u64("size_bytes", 0444, dir, &nbd->bytesize);
-	if (IS_ERR_OR_NULL(f)) {
-		dev_err(nbd_to_dev(nbd), "Failed to create debugfs file 'size_bytes', %ld\n",
-			PTR_ERR(f));
-		return PTR_ERR(f);
-	}
-
-	f = debugfs_create_u32("timeout", 0444, dir, &nbd->xmit_timeout);
-	if (IS_ERR_OR_NULL(f)) {
-		dev_err(nbd_to_dev(nbd), "Failed to create debugfs file 'timeout', %ld\n",
-			PTR_ERR(f));
-		return PTR_ERR(f);
-	}
-
-	f = debugfs_create_u32("blocksize", 0444, dir, &nbd->blksize);
-	if (IS_ERR_OR_NULL(f)) {
-		dev_err(nbd_to_dev(nbd), "Failed to create debugfs file 'blocksize', %ld\n",
-			PTR_ERR(f));
-		return PTR_ERR(f);
-	}
-
-	f = debugfs_create_file("flags", 0444, dir, &nbd, &nbd_dbg_flags_ops);
-	if (IS_ERR_OR_NULL(f)) {
-		dev_err(nbd_to_dev(nbd), "Failed to create debugfs file 'flags', %ld\n",
-			PTR_ERR(f));
-		return PTR_ERR(f);
-	}
-
-	return 0;
-}
-
-static void nbd_dev_dbg_close(struct nbd_device *nbd)
-{
-	debugfs_remove_recursive(nbd->dbg_dir);
-}
-
-static int nbd_dbg_init(void)
-{
-	struct dentry *dbg_dir;
-
-	dbg_dir = debugfs_create_dir("nbd", NULL);
-	if (IS_ERR(dbg_dir))
-		return PTR_ERR(dbg_dir);
-
-	nbd_dbg_dir = dbg_dir;
-
-	return 0;
-}
-
-static void nbd_dbg_close(void)
-{
-	debugfs_remove_recursive(nbd_dbg_dir);
-}
-
-#else  /* IS_ENABLED(CONFIG_DEBUG_FS) */
-
-static int nbd_dev_dbg_init(struct nbd_device *nbd)
-{
-	return 0;
-}
-
-static void nbd_dev_dbg_close(struct nbd_device *nbd)
-{
-}
-
-static int nbd_dbg_init(void)
-{
-	return 0;
-}
-
-static void nbd_dbg_close(void)
-{
-}
-
-#endif
-
-/*
- * And here should be modules and kernel interface 
- *  (Just smiley confuses emacs :-)
- */
-
-static int __init nbd_init(void)
-{
-	int err = -ENOMEM;
-	int i;
-	int part_shift;
-
-	BUILD_BUG_ON(sizeof(struct nbd_request) != 28);
-
-	if (max_part < 0) {
-		printk(KERN_ERR "nbd: max_part must be >= 0\n");
-		return -EINVAL;
-	}
-
-	part_shift = 0;
-	if (max_part > 0) {
-		part_shift = fls(max_part);
-
-		/*
-		 * Adjust max_part according to part_shift as it is exported
-		 * to user space so that user can know the max number of
-		 * partition kernel should be able to manage.
-		 *
-		 * Note that -1 is required because partition 0 is reserved
-		 * for the whole disk.
-		 */
-		max_part = (1UL << part_shift) - 1;
-	}
-
-	if ((1UL << part_shift) > DISK_MAX_PARTS)
-		return -EINVAL;
-
-	if (nbds_max > 1UL << (MINORBITS - part_shift))
-		return -EINVAL;
-
-	nbd_dev = kcalloc(nbds_max, sizeof(*nbd_dev), GFP_KERNEL);
-	if (!nbd_dev)
-		return -ENOMEM;
-
-	for (i = 0; i < nbds_max; i++) {
-		struct gendisk *disk = alloc_disk(1 << part_shift);
-		if (!disk)
-			goto out;
-		nbd_dev[i].disk = disk;
-		/*
-		 * The new linux 2.5 block layer implementation requires
-		 * every gendisk to have its very own request_queue struct.
-		 * These structs are big so we dynamically allocate them.
-		 */
-		disk->queue = blk_init_queue(nbd_request_handler, &nbd_lock);
-		if (!disk->queue) {
-			put_disk(disk);
-			goto out;
-		}
-		/*
-		 * Tell the block layer that we are not a rotational device
-		 */
-		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, disk->queue);
-		queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, disk->queue);
-		disk->queue->limits.discard_granularity = 512;
-		blk_queue_max_discard_sectors(disk->queue, UINT_MAX);
-		disk->queue->limits.discard_zeroes_data = 0;
-		blk_queue_max_hw_sectors(disk->queue, 65536);
-		disk->queue->limits.max_sectors = 256;
-	}
-
-	if (register_blkdev(NBD_MAJOR, "nbd")) {
-		err = -EIO;
-		goto out;
-	}
-
-	printk(KERN_INFO "nbd: registered device at major %d\n", NBD_MAJOR);
-
-	nbd_dbg_init();
-
-	for (i = 0; i < nbds_max; i++) {
-		struct gendisk *disk = nbd_dev[i].disk;
-		nbd_dev[i].magic = NBD_MAGIC;
-		INIT_LIST_HEAD(&nbd_dev[i].waiting_queue);
-		spin_lock_init(&nbd_dev[i].queue_lock);
-		spin_lock_init(&nbd_dev[i].tasks_lock);
-		INIT_LIST_HEAD(&nbd_dev[i].queue_head);
-		mutex_init(&nbd_dev[i].tx_lock);
-		init_timer(&nbd_dev[i].timeout_timer);
-		nbd_dev[i].timeout_timer.function = nbd_xmit_timeout;
-		nbd_dev[i].timeout_timer.data = (unsigned long)&nbd_dev[i];
-		init_waitqueue_head(&nbd_dev[i].active_wq);
-		init_waitqueue_head(&nbd_dev[i].waiting_wq);
-		nbd_dev[i].blksize = 1024;
-		nbd_dev[i].bytesize = 0;
-		disk->major = NBD_MAJOR;
-		disk->first_minor = i << part_shift;
-		disk->fops = &nbd_fops;
-		disk->private_data = &nbd_dev[i];
-		sprintf(disk->disk_name, "nbd%d", i);
-		set_capacity(disk, 0);
-		add_disk(disk);
-	}
-
-	return 0;
-out:
-	while (i--) {
-		blk_cleanup_queue(nbd_dev[i].disk->queue);
-		put_disk(nbd_dev[i].disk);
-	}
-	kfree(nbd_dev);
-	return err;
-}
-
-static void __exit nbd_cleanup(void)
-{
-	int i;
-
-	nbd_dbg_close();
-
-	for (i = 0; i < nbds_max; i++) {
-		struct gendisk *disk = nbd_dev[i].disk;
-		nbd_dev[i].magic = 0;
-		if (disk) {
-			del_gendisk(disk);
-			blk_cleanup_queue(disk->queue);
-			put_disk(disk);
-		}
-	}
-	unregister_blkdev(NBD_MAJOR, "nbd");
-	kfree(nbd_dev);
-	printk(KERN_INFO "nbd: unregistered device at major %d\n", NBD_MAJOR);
-}
-
-module_init(nbd_init);
-module_exit(nbd_cleanup);
-
-MODULE_DESCRIPTION("Network Block Device");
-MODULE_LICENSE("GPL");
-
-module_param(nbds_max, int, 0444);
-MODULE_PARM_DESC(nbds_max, "number of network block devices to initialize (default: 16)");
-module_param(max_part, int, 0444);
-MODULE_PARM_DESC(max_part, "number of partitions per device (default: 0)");