]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/char/vt.c
tty: shutdown method
[linux-2.6-omap-h63xx.git] / drivers / char / vt.c
index 1bc00c9d860d70f917f2d945162aad3755b31749..37a45db5bae080a376c37902643b9d44fcc3fbd9 100644 (file)
@@ -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)
@@ -2094,27 +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;
 
@@ -2541,8 +2565,6 @@ 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))
@@ -2736,6 +2758,12 @@ 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;
 
@@ -2765,25 +2793,18 @@ static int con_open(struct tty_struct *tty, struct file *filp)
  */
 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)
@@ -2907,6 +2928,8 @@ 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)
@@ -4061,7 +4084,6 @@ 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);