Signed-Off-By: Paul Clements --- ./drivers/block/nbd.c.SIZE_ZERO 2007-08-16 13:08:06.000000000 -0400 +++ ./drivers/block/nbd.c 2007-08-23 16:42:09.000000000 -0400 @@ -113,12 +113,42 @@ static void nbd_end_request(struct reque 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 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 current->pid, current->comm, dequeue_signal_lock(current, ¤t->blocked, &info)); result = -EINTR; + sock_shutdown(lo, !send); break; } @@ -167,23 +209,22 @@ static int sock_xmit(struct socket *sock 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, i, 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_devic 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); @@ -219,7 +260,7 @@ static int nbd_send_req(struct nbd_devic 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, @@ -261,11 +302,11 @@ 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; @@ -277,10 +318,9 @@ static struct request *nbd_read_stat(str 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); @@ -322,7 +362,7 @@ static struct request *nbd_read_stat(str rq_for_each_bio(bio, req) { struct bio_vec *bvec; bio_for_each_segment(bvec, bio, i) { - 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, @@ -401,6 +441,7 @@ static void nbd_clear_que(struct nbd_dev } } + /* * We always wait for result of write, for now. It would be nice to make it optional * in future @@ -511,7 +552,9 @@ static int nbd_ioctl(struct inode *inode 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: @@ -555,6 +598,9 @@ static int nbd_ioctl(struct inode *inode 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; @@ -567,22 +613,7 @@ static int nbd_ioctl(struct inode *inode 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); --- ./include/linux/nbd.h.PRISTINE 2007-08-22 13:15:45.000000000 -0400 +++ ./include/linux/nbd.h 2007-08-22 13:17:02.000000000 -0400 @@ -26,6 +26,7 @@ #define NBD_PRINT_DEBUG _IO( 0xab, 6 ) #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) #define NBD_DISCONNECT _IO( 0xab, 8 ) +#define NBD_SET_TIMEOUT _IO( 0xab, 9 ) enum { NBD_CMD_READ = 0, @@ -65,6 +66,7 @@ struct nbd_device { int blksize; u64 bytesize; pid_t pid; /* pid of nbd-client, if attached */ + int xmit_timeout; }; #endif