diff options
| -rw-r--r-- | drivers/char/tty_io.c | 72 | ||||
| -rw-r--r-- | drivers/char/vt.c | 82 | ||||
| -rw-r--r-- | drivers/char/vt_ioctl.c | 4 | ||||
| -rw-r--r-- | include/linux/tty.h | 2 | ||||
| -rw-r--r-- | include/linux/tty_driver.h | 14 | ||||
| -rw-r--r-- | include/linux/vt_kern.h | 1 |
6 files changed, 121 insertions, 54 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 0e6866f..a27160b 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -2496,45 +2496,25 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) } /** - * 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); @@ -2550,14 +2530,42 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty, 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 * diff --git a/drivers/char/vt.c b/drivers/char/vt.c index 1bc00c9..60359c3 100644 --- a/drivers/char/vt.c +++ b/drivers/char/vt.c @@ -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; @@ -907,24 +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; - - 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)) @@ -932,14 +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) +{ + 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) @@ -2907,6 +2949,7 @@ static const struct tty_operations con_ops = { .start = con_start, .throttle = con_throttle, .unthrottle = con_unthrottle, + .resize = vt_resize, }; int __init vty_init(void) @@ -4061,7 +4104,6 @@ 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); diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c index 3211afd..c904e9a 100644 --- a/drivers/char/vt_ioctl.c +++ b/drivers/char/vt_ioctl.c @@ -947,14 +947,16 @@ int vt_ioctl(struct tty_struct *tty, struct file * file, 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; } diff --git a/include/linux/tty.h b/include/linux/tty.h index e3579cb..0cbec74 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -331,6 +331,8 @@ extern int tty_write_room(struct tty_struct *tty); 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); diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h index e1065ac..16d2794 100644 --- a/include/linux/tty_driver.h +++ b/include/linux/tty_driver.h @@ -168,6 +168,18 @@ * * 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> @@ -206,6 +218,8 @@ struct tty_operations { 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); diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h index 1c78d56..1cbd0a7 100644 --- a/include/linux/vt_kern.h +++ b/include/linux/vt_kern.h @@ -35,7 +35,6 @@ extern int fg_console, last_console, want_console; 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); |