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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.c93
1 files changed, 62 insertions, 31 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 89bdafd88dbd..cb136a919f2a 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -113,12 +113,42 @@ static void nbd_end_request(struct request *req)
spin_unlock_irqrestore(q->queue_lock, flags);
}
+static void sock_shutdown(struct nbd_device *lo, int lock)
+{
+ /* Forcibly shutdown the socket causing all listeners
+ * to error
+ *
+ * FIXME: This code is duplicated from sys_shutdown, but
+ * there should be a more generic interface rather than
+ * calling socket ops directly here */
+ if (lock)
+ mutex_lock(&lo->tx_lock);
+ if (lo->sock) {
+ printk(KERN_WARNING "%s: shutting down socket\n",
+ lo->disk->disk_name);
+ lo->sock->ops->shutdown(lo->sock, SEND_SHUTDOWN|RCV_SHUTDOWN);
+ lo->sock = NULL;
+ }
+ if (lock)
+ mutex_unlock(&lo->tx_lock);
+}
+
+static void nbd_xmit_timeout(unsigned long arg)
+{
+ struct task_struct *task = (struct task_struct *)arg;
+
+ printk(KERN_WARNING "nbd: killing hung xmit (%s, pid: %d)\n",
+ task->comm, task->pid);
+ force_sig(SIGKILL, task);
+}
+
/*
* Send or receive packet.
*/
-static int sock_xmit(struct socket *sock, int send, void *buf, int size,
+static int sock_xmit(struct nbd_device *lo, int send, void *buf, int size,
int msg_flags)
{
+ struct socket *sock = lo->sock;
int result;
struct msghdr msg;
struct kvec iov;
@@ -139,9 +169,20 @@ static int sock_xmit(struct socket *sock, int send, void *buf, int size,
msg.msg_controllen = 0;
msg.msg_flags = msg_flags | MSG_NOSIGNAL;
- if (send)
+ if (send) {
+ struct timer_list ti;
+
+ if (lo->xmit_timeout) {
+ init_timer(&ti);
+ ti.function = nbd_xmit_timeout;
+ ti.data = (unsigned long)current;
+ ti.expires = jiffies + lo->xmit_timeout;
+ add_timer(&ti);
+ }
result = kernel_sendmsg(sock, &msg, &iov, 1, size);
- else
+ if (lo->xmit_timeout)
+ del_timer_sync(&ti);
+ } else
result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0);
if (signal_pending(current)) {
@@ -150,6 +191,7 @@ static int sock_xmit(struct socket *sock, int send, void *buf, int size,
current->pid, current->comm,
dequeue_signal_lock(current, &current->blocked, &info));
result = -EINTR;
+ sock_shutdown(lo, !send);
break;
}
@@ -167,23 +209,22 @@ static int sock_xmit(struct socket *sock, int send, void *buf, int size,
return result;
}
-static inline int sock_send_bvec(struct socket *sock, struct bio_vec *bvec,
+static inline int sock_send_bvec(struct nbd_device *lo, struct bio_vec *bvec,
int flags)
{
int result;
void *kaddr = kmap(bvec->bv_page);
- result = sock_xmit(sock, 1, kaddr + bvec->bv_offset, bvec->bv_len,
- flags);
+ result = sock_xmit(lo, 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 *lo, struct request *req)
{
int result, flags;
struct nbd_request request;
unsigned long size = req->nr_sectors << 9;
- struct socket *sock = lo->sock;
request.magic = htonl(NBD_REQUEST_MAGIC);
request.type = htonl(nbd_cmd(req));
@@ -196,8 +237,8 @@ static int nbd_send_req(struct nbd_device *lo, struct request *req)
nbdcmd_to_ascii(nbd_cmd(req)),
(unsigned long long)req->sector << 9,
req->nr_sectors << 9);
- result = sock_xmit(sock, 1, &request, sizeof(request),
- (nbd_cmd(req) == NBD_CMD_WRITE)? MSG_MORE: 0);
+ result = sock_xmit(lo, 1, &request, sizeof(request),
+ (nbd_cmd(req) == NBD_CMD_WRITE) ? MSG_MORE : 0);
if (result <= 0) {
printk(KERN_ERR "%s: Send control failed (result %d)\n",
lo->disk->disk_name, result);
@@ -217,7 +258,7 @@ static int nbd_send_req(struct nbd_device *lo, struct request *req)
flags = MSG_MORE;
dprintk(DBG_TX, "%s: request %p: sending %d bytes data\n",
lo->disk->disk_name, req, bvec->bv_len);
- result = sock_send_bvec(sock, bvec, flags);
+ result = sock_send_bvec(lo, bvec, flags);
if (result <= 0) {
printk(KERN_ERR "%s: Send data failed (result %d)\n",
lo->disk->disk_name, result);
@@ -257,11 +298,11 @@ out:
return ERR_PTR(err);
}
-static inline int sock_recv_bvec(struct socket *sock, struct bio_vec *bvec)
+static inline int sock_recv_bvec(struct nbd_device *lo, struct bio_vec *bvec)
{
int result;
void *kaddr = kmap(bvec->bv_page);
- result = sock_xmit(sock, 0, kaddr + bvec->bv_offset, bvec->bv_len,
+ result = sock_xmit(lo, 0, kaddr + bvec->bv_offset, bvec->bv_len,
MSG_WAITALL);
kunmap(bvec->bv_page);
return result;
@@ -273,10 +314,9 @@ static struct request *nbd_read_stat(struct nbd_device *lo)
int result;
struct nbd_reply reply;
struct request *req;
- struct socket *sock = lo->sock;
reply.magic = 0;
- result = sock_xmit(sock, 0, &reply, sizeof(reply), MSG_WAITALL);
+ result = sock_xmit(lo, 0, &reply, sizeof(reply), MSG_WAITALL);
if (result <= 0) {
printk(KERN_ERR "%s: Receive control failed (result %d)\n",
lo->disk->disk_name, result);
@@ -317,7 +357,7 @@ static struct request *nbd_read_stat(struct nbd_device *lo)
struct bio_vec *bvec;
rq_for_each_segment(bvec, req, iter) {
- result = sock_recv_bvec(sock, bvec);
+ result = sock_recv_bvec(lo, bvec);
if (result <= 0) {
printk(KERN_ERR "%s: Receive data failed (result %d)\n",
lo->disk->disk_name, result);
@@ -392,6 +432,7 @@ static void nbd_clear_que(struct nbd_device *lo)
}
}
+
/*
* We always wait for result of write, for now. It would be nice to make it optional
* in future
@@ -500,7 +541,9 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
sreq.nr_sectors = 0;
if (!lo->sock)
return -EINVAL;
+ mutex_lock(&lo->tx_lock);
nbd_send_req(lo, &sreq);
+ mutex_unlock(&lo->tx_lock);
return 0;
case NBD_CLEAR_SOCK:
@@ -544,6 +587,9 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
set_blocksize(inode->i_bdev, lo->blksize);
set_capacity(lo->disk, lo->bytesize >> 9);
return 0;
+ case NBD_SET_TIMEOUT:
+ lo->xmit_timeout = arg * HZ;
+ return 0;
case NBD_SET_SIZE_BLOCKS:
lo->bytesize = ((u64) arg) * lo->blksize;
inode->i_bdev->bd_inode->i_size = lo->bytesize;
@@ -556,22 +602,7 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
error = nbd_do_it(lo);
if (error)
return error;
- /* on return tidy up in case we have a signal */
- /* Forcibly shutdown the socket causing all listeners
- * to error
- *
- * FIXME: This code is duplicated from sys_shutdown, but
- * there should be a more generic interface rather than
- * calling socket ops directly here */
- mutex_lock(&lo->tx_lock);
- if (lo->sock) {
- printk(KERN_WARNING "%s: shutting down socket\n",
- lo->disk->disk_name);
- lo->sock->ops->shutdown(lo->sock,
- SEND_SHUTDOWN|RCV_SHUTDOWN);
- lo->sock = NULL;
- }
- mutex_unlock(&lo->tx_lock);
+ sock_shutdown(lo, 1);
file = lo->file;
lo->file = NULL;
nbd_clear_que(lo);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.