diff options
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/nbd.c | 98 |
1 files changed, 70 insertions, 28 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index f169faf..f3536e6 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -59,6 +59,10 @@ struct nbd_device { pid_t pid; /* pid of nbd-client, if attached */ int xmit_timeout; int disconnect; /* a disconnect has been requested by user */ + + struct timer_list timeout_timer; + struct task_struct *task_recv; + struct task_struct *task_send; }; #define NBD_MAGIC 0x68797548 @@ -121,6 +125,7 @@ static void sock_shutdown(struct nbd_device *nbd, int lock) 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); } if (lock) mutex_unlock(&nbd->tx_lock); @@ -128,11 +133,23 @@ static void sock_shutdown(struct nbd_device *nbd, int lock) static void nbd_xmit_timeout(unsigned long arg) { - struct task_struct *task = (struct task_struct *)arg; + struct nbd_device *nbd = (struct nbd_device *)arg; + struct task_struct *task; + + if (list_empty(&nbd->queue_head)) + return; + + nbd->disconnect = 1; + + task = READ_ONCE(nbd->task_recv); + if (task) + force_sig(SIGKILL, task); - printk(KERN_WARNING "nbd: killing hung xmit (%s, pid: %d)\n", - task->comm, task->pid); - force_sig(SIGKILL, task); + task = READ_ONCE(nbd->task_send); + if (task) + force_sig(SIGKILL, nbd->task_send); + + dev_err(nbd_to_dev(nbd), "Connection timed out, killed receiver and sender, shutting down connection\n"); } /* @@ -171,33 +188,12 @@ static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size, msg.msg_controllen = 0; msg.msg_flags = msg_flags | MSG_NOSIGNAL; - if (send) { - struct timer_list ti; - - if (nbd->xmit_timeout) { - init_timer(&ti); - ti.function = nbd_xmit_timeout; - ti.data = (unsigned long)current; - ti.expires = jiffies + nbd->xmit_timeout; - add_timer(&ti); - } + if (send) result = kernel_sendmsg(sock, &msg, &iov, 1, size); - if (nbd->xmit_timeout) - del_timer_sync(&ti); - } else + else result = kernel_recvmsg(sock, &msg, &iov, 1, size, msg.msg_flags); - if (signal_pending(current)) { - siginfo_t info; - printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n", - task_pid_nr(current), current->comm, - dequeue_signal_lock(current, ¤t->blocked, &info)); - result = -EINTR; - sock_shutdown(nbd, !send); - break; - } - if (result <= 0) { if (result == 0) result = -EPIPE; /* short read */ @@ -210,6 +206,9 @@ static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size, 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; } @@ -415,12 +414,26 @@ static int nbd_do_it(struct nbd_device *nbd) return ret; } + nbd->task_recv = current; + while ((req = nbd_read_stat(nbd)) != NULL) nbd_end_request(nbd, req); + nbd->task_recv = NULL; + + if (signal_pending(current)) { + siginfo_t info; + + ret = dequeue_signal_lock(current, ¤t->blocked, &info); + dev_warn(nbd_to_dev(nbd), "pid %d, %s, got signal %d\n", + task_pid_nr(current), current->comm, ret); + sock_shutdown(nbd, 1); + ret = -ETIMEDOUT; + } + device_remove_file(disk_to_dev(nbd->disk), &pid_attr); nbd->pid = 0; - return 0; + return ret; } static void nbd_clear_que(struct nbd_device *nbd) @@ -482,6 +495,9 @@ static void nbd_handle_req(struct nbd_device *nbd, struct request *req) 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++; @@ -508,6 +524,8 @@ static int nbd_thread(void *data) struct nbd_device *nbd = data; struct request *req; + nbd->task_send = current; + set_user_nice(current, MIN_NICE); while (!kthread_should_stop() || !list_empty(&nbd->waiting_queue)) { /* wait for something to do */ @@ -515,6 +533,18 @@ static int nbd_thread(void *data) kthread_should_stop() || !list_empty(&nbd->waiting_queue)); + if (signal_pending(current)) { + siginfo_t info; + int ret; + + ret = dequeue_signal_lock(current, ¤t->blocked, + &info); + dev_warn(nbd_to_dev(nbd), "pid %d, %s, got signal %d\n", + task_pid_nr(current), current->comm, ret); + sock_shutdown(nbd, 1); + break; + } + /* extract request */ if (list_empty(&nbd->waiting_queue)) continue; @@ -528,6 +558,9 @@ static int nbd_thread(void *data) /* handle request */ nbd_handle_req(nbd, req); } + + nbd->task_send = NULL; + return 0; } @@ -648,6 +681,12 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, 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: @@ -842,6 +881,9 @@ static int __init nbd_init(void) spin_lock_init(&nbd_dev[i].queue_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; |