1 files changed, 93 insertions, 75 deletions

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 82a51f38a54..57029fefd64 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -100,10 +100,10 @@
 #include <linux/font.h>
 #include <linux/bitops.h>
 #include <linux/notifier.h>
-
-#include <asm/io.h>
+#include <linux/device.h>
+#include <linux/io.h>
 #include <asm/system.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 
 #define MAX_NR_CON_DRIVER 16
 
@@ -803,7 +803,25 @@ static inline int resize_screen(struct vc_data *vc, int width, int height,
  */
 #define VC_RESIZE_MAXCOL (32767)
 #define VC_RESIZE_MAXROW (32767)
-int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int lines)
+
+/**
+ *	vc_do_resize	-	resizing method for the tty
+ *	@tty: tty being resized
+ *	@real_tty: real tty (different to tty if a pty/tty pair)
+ *	@vc: virtual console private data
+ *	@cols: columns
+ *	@lines: lines
+ *
+ *	Resize a virtual console, clipping according to the actual constraints.
+ *	If the caller passes a tty structure then update the termios winsize
+ *	information and perform any neccessary signal handling.
+ *
+ *	Caller must hold the console semaphore. Takes the termios mutex and
+ *	ctrl_lock of the tty IFF a tty is passed.
+ */
+
+static int vc_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
+		struct vc_data *vc, unsigned int cols, unsigned int lines)
 {
 	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
 	unsigned int old_cols, old_rows, old_row_size, old_screen_size;
@@ -907,26 +925,15 @@ int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int lines)
 	gotoxy(vc, vc->vc_x, vc->vc_y);
 	save_cur(vc);
 
-	if (vc->vc_tty) {
-		struct winsize ws, *cws = &vc->vc_tty->winsize;
-		struct pid *pgrp = NULL;
-
+	if (tty) {
+		/* Rewrite the requested winsize data with the actual
+		   resulting sizes */
+		struct winsize ws;
 		memset(&ws, 0, sizeof(ws));
 		ws.ws_row = vc->vc_rows;
 		ws.ws_col = vc->vc_cols;
 		ws.ws_ypixel = vc->vc_scan_lines;
-
-		mutex_lock(&vc->vc_tty->termios_mutex);
-		spin_lock_irq(&vc->vc_tty->ctrl_lock);
-		if ((ws.ws_row != cws->ws_row || ws.ws_col != cws->ws_col))
-			pgrp = get_pid(vc->vc_tty->pgrp);
-		spin_unlock_irq(&vc->vc_tty->ctrl_lock);
-		if (pgrp) {
-			kill_pgrp(vc->vc_tty->pgrp, SIGWINCH, 1);
-			put_pid(pgrp);
-		}
-		*cws = ws;
-		mutex_unlock(&vc->vc_tty->termios_mutex);
+		tty_do_resize(tty, real_tty, &ws);
 	}
 
 	if (CON_IS_VISIBLE(vc))
@@ -934,14 +941,47 @@ int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int lines)
 	return err;
 }
 
-int vc_lock_resize(struct vc_data *vc, unsigned int cols, unsigned int lines)
+/**
+ *	vc_resize		-	resize a VT
+ *	@vc: virtual console
+ *	@cols: columns
+ *	@rows: rows
+ *
+ *	Resize a virtual console as seen from the console end of things. We
+ *	use the common vc_do_resize methods to update the structures. The
+ *	caller must hold the console sem to protect console internals and
+ *	vc->vc_tty
+ */
+
+int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
 {
-	int rc;
+	return vc_do_resize(vc->vc_tty, vc->vc_tty, vc, cols, rows);
+}
+
+/**
+ *	vt_resize		-	resize a VT
+ *	@tty: tty to resize
+ *	@real_tty: tty if a pty/tty pair
+ *	@ws: winsize attributes
+ *
+ *	Resize a virtual terminal. This is called by the tty layer as we
+ *	register our own handler for resizing. The mutual helper does all
+ *	the actual work.
+ *
+ *	Takes the console sem and the called methods then take the tty
+ *	termios_mutex and the tty ctrl_lock in that order.
+ */
+
+int vt_resize(struct tty_struct *tty, struct tty_struct *real_tty,
+	struct winsize *ws)
+{
+	struct vc_data *vc = tty->driver_data;
+	int ret;
 
 	acquire_console_sem();
-	rc = vc_resize(vc, cols, lines);
+	ret = vc_do_resize(tty, real_tty, vc, ws->ws_col, ws->ws_row);
 	release_console_sem();
-	return rc;
+	return ret;
 }
 
 void vc_deallocate(unsigned int currcons)
@@ -2096,27 +2136,9 @@ static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int co
 	    release_console_sem();
 	    return 0;
 	}
-	release_console_sem();
-
 	orig_buf = buf;
 	orig_count = count;
 
-	/* At this point 'buf' is guaranteed to be a kernel buffer
-	 * and therefore no access to userspace (and therefore sleeping)
-	 * will be needed.  The con_buf_mtx serializes all tty based
-	 * console rendering and vcs write/read operations.  We hold
-	 * the console spinlock during the entire write.
-	 */
-
-	acquire_console_sem();
-
-	vc = tty->driver_data;
-	if (vc == NULL) {
-		printk(KERN_ERR "vt: argh, driver_data _became_ NULL !\n");
-		release_console_sem();
-		goto out;
-	}
-
 	himask = vc->vc_hi_font_mask;
 	charmask = himask ? 0x1ff : 0xff;
 
@@ -2330,8 +2352,6 @@ rescan_last_byte:
 	FLUSH
 	console_conditional_schedule();
 	release_console_sem();
-
-out:
 	notify_update(vc);
 	return n;
 #undef FLUSH
@@ -2543,8 +2563,6 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
 	int lines;
 	int ret;
 
-	if (tty->driver->type != TTY_DRIVER_TYPE_CONSOLE)
-		return -EINVAL;
 	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
 		return -EPERM;
 	if (get_user(type, p))
@@ -2738,6 +2756,12 @@ static int con_open(struct tty_struct *tty, struct file *filp)
 		ret = vc_allocate(currcons);
 		if (ret == 0) {
 			struct vc_data *vc = vc_cons[currcons].d;
+
+			/* Still being freed */
+			if (vc->vc_tty) {
+				release_console_sem();
+				return -ERESTARTSYS;
+			}
 			tty->driver_data = vc;
 			vc->vc_tty = tty;
 
@@ -2758,34 +2782,20 @@ static int con_open(struct tty_struct *tty, struct file *filp)
 	return ret;
 }
 
-/*
- * We take tty_mutex in here to prevent another thread from coming in via init_dev
- * and taking a ref against the tty while we're in the process of forgetting
- * about it and cleaning things up.
- *
- * This is because vcs_remove_sysfs() can sleep and will drop the BKL.
- */
 static void con_close(struct tty_struct *tty, struct file *filp)
 {
-	mutex_lock(&tty_mutex);
-	acquire_console_sem();
-	if (tty && tty->count == 1) {
-		struct vc_data *vc = tty->driver_data;
+	/* Nothing to do - we defer to shutdown */
+}
 
-		if (vc)
-			vc->vc_tty = NULL;
-		tty->driver_data = NULL;
-		vcs_remove_sysfs(tty);
-		release_console_sem();
-		mutex_unlock(&tty_mutex);
-		/*
-		 * tty_mutex is released, but we still hold BKL, so there is
-		 * still exclusion against init_dev()
-		 */
-		return;
-	}
+static void con_shutdown(struct tty_struct *tty)
+{
+	struct vc_data *vc = tty->driver_data;
+	BUG_ON(vc == NULL);
+	acquire_console_sem();
+	vc->vc_tty = NULL;
+	vcs_remove_sysfs(tty);
 	release_console_sem();
-	mutex_unlock(&tty_mutex);
+	tty_shutdown(tty);
 }
 
 static int default_italic_color    = 2; // green (ASCII)
@@ -2909,10 +2919,20 @@ static const struct tty_operations con_ops = {
 	.start = con_start,
 	.throttle = con_throttle,
 	.unthrottle = con_unthrottle,
+	.resize = vt_resize,
+	.shutdown = con_shutdown
 };
 
-int __init vty_init(void)
+static struct cdev vc0_cdev;
+
+int __init vty_init(const struct file_operations *console_fops)
 {
+	cdev_init(&vc0_cdev, console_fops);
+	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
+	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
+		panic("Couldn't register /dev/tty0 driver\n");
+	device_create(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
+
 	vcs_init();
 
 	console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
@@ -2931,7 +2951,6 @@ int __init vty_init(void)
 	tty_set_operations(console_driver, &con_ops);
 	if (tty_register_driver(console_driver))
 		panic("Couldn't register console driver\n");
-
 	kbd_init();
 	console_map_init();
 #ifdef CONFIG_PROM_CONSOLE
@@ -3425,7 +3444,7 @@ int register_con_driver(const struct consw *csw, int first, int last)
 	if (retval)
 		goto err;
 
-	con_driver->dev = device_create_drvdata(vtconsole_class, NULL,
+	con_driver->dev = device_create(vtconsole_class, NULL,
 						MKDEV(0, con_driver->node),
 						NULL, "vtcon%i",
 						con_driver->node);
@@ -3536,7 +3555,7 @@ static int __init vtconsole_class_init(void)
 		struct con_driver *con = &registered_con_driver[i];
 
 		if (con->con && !con->dev) {
-			con->dev = device_create_drvdata(vtconsole_class, NULL,
+			con->dev = device_create(vtconsole_class, NULL,
 							 MKDEV(0, con->node),
 							 NULL, "vtcon%i",
 							 con->node);
@@ -4063,7 +4082,6 @@ EXPORT_SYMBOL(default_blu);
 EXPORT_SYMBOL(update_region);
 EXPORT_SYMBOL(redraw_screen);
 EXPORT_SYMBOL(vc_resize);
-EXPORT_SYMBOL(vc_lock_resize);
 EXPORT_SYMBOL(fg_console);
 EXPORT_SYMBOL(console_blank_hook);
 EXPORT_SYMBOL(console_blanked);