}
/**
- * tiocswinsz - implement window size set ioctl
- * @tty; tty
- * @arg: user buffer for result
+ * tty_do_resize - resize event
+ * @tty: tty being resized
+ * @real_tty: real tty (if using a pty/tty pair)
+ * @rows: rows (character)
+ * @cols: cols (character)
*
- * Copies the user idea of the window size to the kernel. Traditionally
- * this is just advisory information but for the Linux console it
- * actually has driver level meaning and triggers a VC resize.
- *
- * Locking:
- * Called function use the console_sem is used to ensure we do
- * not try and resize the console twice at once.
- * The tty->termios_mutex is used to ensure we don't double
- * resize and get confused. Lock order - tty->termios_mutex before
- * console sem
+ * Update the termios variables and send the neccessary signals to
+ * peform a terminal resize correctly
*/
-static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
- struct winsize __user *arg)
+int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
+ struct winsize *ws)
{
- struct winsize tmp_ws;
struct pid *pgrp, *rpgrp;
unsigned long flags;
- if (copy_from_user(&tmp_ws, arg, sizeof(*arg)))
- return -EFAULT;
-
mutex_lock(&tty->termios_mutex);
- if (!memcmp(&tmp_ws, &tty->winsize, sizeof(*arg)))
+ if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
goto done;
-
-#ifdef CONFIG_VT
- if (tty->driver->type == TTY_DRIVER_TYPE_CONSOLE) {
- if (vc_lock_resize(tty->driver_data, tmp_ws.ws_col,
- tmp_ws.ws_row)) {
- mutex_unlock(&tty->termios_mutex);
- return -ENXIO;
- }
- }
-#endif
/* Get the PID values and reference them so we can
avoid holding the tty ctrl lock while sending signals */
spin_lock_irqsave(&tty->ctrl_lock, flags);
put_pid(pgrp);
put_pid(rpgrp);
- tty->winsize = tmp_ws;
- real_tty->winsize = tmp_ws;
+ tty->winsize = *ws;
+ real_tty->winsize = *ws;
done:
mutex_unlock(&tty->termios_mutex);
return 0;
}
+/**
+ * tiocswinsz - implement window size set ioctl
+ * @tty; tty
+ * @arg: user buffer for result
+ *
+ * Copies the user idea of the window size to the kernel. Traditionally
+ * this is just advisory information but for the Linux console it
+ * actually has driver level meaning and triggers a VC resize.
+ *
+ * Locking:
+ * Driver dependant. The default do_resize method takes the
+ * tty termios mutex and ctrl_lock. The console takes its own lock
+ * then calls into the default method.
+ */
+
+static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
+ struct winsize __user *arg)
+{
+ struct winsize tmp_ws;
+ if (copy_from_user(&tmp_ws, arg, sizeof(*arg)))
+ return -EFAULT;
+
+ if (tty->ops->resize)
+ return tty->ops->resize(tty, real_tty, &tmp_ws);
+ else
+ return tty_do_resize(tty, real_tty, &tmp_ws);
+}
+
/**
* tioccons - allow admin to move logical console
* @file: the file to become console
*/
#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;
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;
-
- 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;
+ tty_do_resize(tty, real_tty, &ws);
}
if (CON_IS_VISIBLE(vc))
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)
+{
+ 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)
{
- int rc;
+ 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)
.start = con_start,
.throttle = con_throttle,
.unthrottle = con_unthrottle,
+ .resize = vt_resize,
};
int __init vty_init(void)
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);
get_user(cc, &vtsizes->v_cols))
ret = -EFAULT;
else {
+ acquire_console_sem();
for (i = 0; i < MAX_NR_CONSOLES; i++) {
vc = vc_cons[i].d;
if (vc) {
vc->vc_resize_user = 1;
- vc_lock_resize(vc_cons[i].d, cc, ll);
+ vc_resize(vc_cons[i].d, cc, ll);
}
}
+ release_console_sem();
}
break;
}
extern void tty_driver_flush_buffer(struct tty_struct *tty);
extern void tty_throttle(struct tty_struct *tty);
extern void tty_unthrottle(struct tty_struct *tty);
+extern int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
+ struct winsize *ws);
extern int is_current_pgrp_orphaned(void);
extern struct pid *tty_get_pgrp(struct tty_struct *tty);
*
* Optional: If not provided then the write method is called under
* the atomic write lock to keep it serialized with the ldisc.
+ *
+ * int (*resize)(struct tty_struct *tty, struct tty_struct *real_tty,
+ * unsigned int rows, unsigned int cols);
+ *
+ * Called when a termios request is issued which changes the
+ * requested terminal geometry.
+ *
+ * Optional: the default action is to update the termios structure
+ * without error. This is usually the correct behaviour. Drivers should
+ * not force errors here if they are not resizable objects (eg a serial
+ * line). See tty_do_resize() if you need to wrap the standard method
+ * in your own logic - the usual case.
*/
#include <linux/fs.h>
int (*tiocmget)(struct tty_struct *tty, struct file *file);
int (*tiocmset)(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear);
+ int (*resize)(struct tty_struct *tty, struct tty_struct *real_tty,
+ struct winsize *ws);
#ifdef CONFIG_CONSOLE_POLL
int (*poll_init)(struct tty_driver *driver, int line, char *options);
int (*poll_get_char)(struct tty_driver *driver, int line);
int vc_allocate(unsigned int console);
int vc_cons_allocated(unsigned int console);
int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int lines);
-int vc_lock_resize(struct vc_data *vc, unsigned int cols, unsigned int lines);
void vc_deallocate(unsigned int console);
void reset_palette(struct vc_data *vc);
void do_blank_screen(int entering_gfx);
projects / GitHub / LineageOS / G12 / android_kernel_amlogic_linux-4.9.git / commitdiff