X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fchar%2Fn_hdlc.c;h=69ec6399c714b206ea11de8c30d8ba75fd0a9bd6;hb=8cc7117e7c4968b10fd7327b4a62d9c23082a7b3;hp=337a87f86a3bff05dc22eb296591ac1c5ae5e03d;hpb=6ab3d5624e172c553004ecc862bfeac16d9d68b7;p=safe%2Fjmp%2Flinux-2.6 diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c index 337a87f..69ec639 100644 --- a/drivers/char/n_hdlc.c +++ b/drivers/char/n_hdlc.c @@ -199,7 +199,7 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty); #define tty2n_hdlc(tty) ((struct n_hdlc *) ((tty)->disc_data)) #define n_hdlc2tty(n_hdlc) ((n_hdlc)->tty) -static struct tty_ldisc n_hdlc_ldisc = { +static struct tty_ldisc_ops n_hdlc_ldisc = { .owner = THIS_MODULE, .magic = TTY_LDISC_MAGIC, .name = "hdlc", @@ -229,7 +229,7 @@ static void n_hdlc_release(struct n_hdlc *n_hdlc) wake_up_interruptible (&tty->read_wait); wake_up_interruptible (&tty->write_wait); - if (tty != NULL && tty->disc_data == n_hdlc) + if (tty->disc_data == n_hdlc) tty->disc_data = NULL; /* Break the tty->n_hdlc link */ /* Release transmit and receive buffers */ @@ -342,12 +342,10 @@ static int n_hdlc_tty_open (struct tty_struct *tty) #endif /* Flush any pending characters in the driver and discipline. */ - - if (tty->ldisc.flush_buffer) - tty->ldisc.flush_buffer (tty); + if (tty->ldisc.ops->flush_buffer) + tty->ldisc.ops->flush_buffer(tty); - if (tty->driver->flush_buffer) - tty->driver->flush_buffer (tty); + tty_driver_flush_buffer(tty); if (debuglevel >= DEBUG_LEVEL_INFO) printk("%s(%d)n_hdlc_tty_open() success\n",__FILE__,__LINE__); @@ -399,8 +397,13 @@ static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty) /* Send the next block of data to device */ tty->flags |= (1 << TTY_DO_WRITE_WAKEUP); - actual = tty->driver->write(tty, tbuf->buf, tbuf->count); - + actual = tty->ops->write(tty, tbuf->buf, tbuf->count); + + /* rollback was possible and has been done */ + if (actual == -ERESTARTSYS) { + n_hdlc->tbuf = tbuf; + break; + } /* if transmit error, throw frame away by */ /* pretending it was accepted by driver */ if (actual < 0) @@ -496,7 +499,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, __FILE__,__LINE__, count); /* This can happen if stuff comes in on the backup tty */ - if (n_hdlc == 0 || tty != n_hdlc->tty) + if (!n_hdlc || tty != n_hdlc->tty) return; /* verify line is using HDLC discipline */ @@ -573,26 +576,36 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file, return -EFAULT; } + lock_kernel(); + for (;;) { - if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) + if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) { + unlock_kernel(); return -EIO; + } n_hdlc = tty2n_hdlc (tty); if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC || - tty != n_hdlc->tty) + tty != n_hdlc->tty) { + unlock_kernel(); return 0; + } rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list); if (rbuf) break; /* no data */ - if (file->f_flags & O_NONBLOCK) + if (file->f_flags & O_NONBLOCK) { + unlock_kernel(); return -EAGAIN; + } interruptible_sleep_on (&tty->read_wait); - if (signal_pending(current)) + if (signal_pending(current)) { + unlock_kernel(); return -EINTR; + } } if (rbuf->count > nr) @@ -613,7 +626,7 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file, kfree(rbuf); else n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,rbuf); - + unlock_kernel(); return ret; } /* end of n_hdlc_tty_read() */ @@ -656,12 +669,18 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file, count = maxframe; } + lock_kernel(); + add_wait_queue(&tty->write_wait, &wait); set_current_state(TASK_INTERRUPTIBLE); /* Allocate transmit buffer */ /* sleep until transmit buffer available */ while (!(tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list))) { + if (file->f_flags & O_NONBLOCK) { + error = -EAGAIN; + break; + } schedule(); n_hdlc = tty2n_hdlc (tty); @@ -690,7 +709,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file, n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf); n_hdlc_send_frames(n_hdlc,tty); } - + unlock_kernel(); return error; } /* end of n_hdlc_tty_write() */ @@ -735,8 +754,7 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file, case TIOCOUTQ: /* get the pending tx byte count in the driver */ - count = tty->driver->chars_in_buffer ? - tty->driver->chars_in_buffer(tty) : 0; + count = tty_chars_in_buffer(tty); /* add size of next output frame in queue */ spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock,flags); if (n_hdlc->tx_buf_list.head) @@ -780,13 +798,14 @@ static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp, poll_wait(filp, &tty->write_wait, wait); /* set bits for operations that won't block */ - if(n_hdlc->rx_buf_list.head) + if (n_hdlc->rx_buf_list.head) mask |= POLLIN | POLLRDNORM; /* readable */ if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) mask |= POLLHUP; - if(tty_hung_up_p(filp)) + if (tty_hung_up_p(filp)) mask |= POLLHUP; - if(n_hdlc->tx_free_buf_list.head) + if (!tty_is_writelocked(tty) && + n_hdlc->tx_free_buf_list.head) mask |= POLLOUT | POLLWRNORM; /* writable */ } return mask; @@ -861,7 +880,7 @@ static void n_hdlc_buf_put(struct n_hdlc_buf_list *list, spin_lock_irqsave(&list->spinlock,flags); buf->link=NULL; - if(list->tail) + if (list->tail) list->tail->link = buf; else list->head = buf;