These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / tty / n_r3964.c

diff --git a/kernel/drivers/tty/n_r3964.c b/kernel/drivers/tty/n_r3964.c
index 8b157d6..3451114 100644 (file)
--- a/kernel/drivers/tty/n_r3964.c
+++ b/kernel/drivers/tty/n_r3964.c
@@ -276,7 +276,7 @@ static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code)
                        add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length,
                                error_code, NULL);
                }
-               wake_up_interruptible(&pInfo->read_wait);
+               wake_up_interruptible(&pInfo->tty->read_wait);
        }
 
        spin_lock_irqsave(&pInfo->lock, flags);
@@ -542,7 +542,7 @@ static void on_receive_block(struct r3964_info *pInfo)
                                pBlock);
                }
        }
-       wake_up_interruptible(&pInfo->read_wait);
+       wake_up_interruptible(&pInfo->tty->read_wait);
 
        pInfo->state = R3964_IDLE;
 
@@ -978,8 +978,8 @@ static int r3964_open(struct tty_struct *tty)
        }
 
        spin_lock_init(&pInfo->lock);
+       mutex_init(&pInfo->read_lock);
        pInfo->tty = tty;
-       init_waitqueue_head(&pInfo->read_wait);
        pInfo->priority = R3964_MASTER;
        pInfo->rx_first = pInfo->rx_last = NULL;
        pInfo->tx_first = pInfo->tx_last = NULL;
@@ -1045,7 +1045,6 @@ static void r3964_close(struct tty_struct *tty)
        }
 
        /* Free buffers: */
-       wake_up_interruptible(&pInfo->read_wait);
        kfree(pInfo->rx_buf);
        TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf);
        kfree(pInfo->tx_buf);
@@ -1065,7 +1064,16 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 
        TRACE_L("read()");
 
-       tty_lock(tty);
+       /*
+        *      Internal serialization of reads.
+        */
+       if (file->f_flags & O_NONBLOCK) {
+               if (!mutex_trylock(&pInfo->read_lock))
+                       return -EAGAIN;
+       } else {
+               if (mutex_lock_interruptible(&pInfo->read_lock))
+                       return -ERESTARTSYS;
+       }
 
        pClient = findClient(pInfo, task_pid(current));
        if (pClient) {
@@ -1077,7 +1085,7 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
                                goto unlock;
                        }
                        /* block until there is a message: */
-                       wait_event_interruptible_tty(tty, pInfo->read_wait,
+                       wait_event_interruptible(tty->read_wait,
                                        (pMsg = remove_msg(pInfo, pClient)));
                }
 
@@ -1107,7 +1115,7 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
        }
        ret = -EPERM;
 unlock:
-       tty_unlock(tty);
+       mutex_unlock(&pInfo->read_lock);
        return ret;
 }
 
@@ -1156,8 +1164,6 @@ static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
        pHeader->locks = 0;
        pHeader->owner = NULL;
 
-       tty_lock(tty);
-
        pClient = findClient(pInfo, task_pid(current));
        if (pClient) {
                pHeader->owner = pClient;
@@ -1175,8 +1181,6 @@ static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
        add_tx_queue(pInfo, pHeader);
        trigger_transmit(pInfo);
 
-       tty_unlock(tty);
-
        return 0;
 }
 
@@ -1227,7 +1231,7 @@ static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
 
        pClient = findClient(pInfo, task_pid(current));
        if (pClient) {
-               poll_wait(file, &pInfo->read_wait, wait);
+               poll_wait(file, &tty->read_wait, wait);
                spin_lock_irqsave(&pInfo->lock, flags);
                pMsg = pClient->first_msg;
                spin_unlock_irqrestore(&pInfo->lock, flags);