tty: vt: pass vc_resize_user as a parameter

It is pretty unfortunate to set vc_data::vc_resize_user in two callers
of vc_do_resize(). vc_resize_user is immediately reset there (while
remembering it). So instead of this back and forth, pass 'from_user' as
a parameter.

Notes on 'int user':
* The name changes from 'user' to 'from_user' on some places to be
  consistent.
* The type is bool now as 'int user' might evoke user's uid or whatever.

Provided vc_resize() is called on many places and they need not to care
about this parameter, its prototype is kept unchanged. Instead, it is
now an inline calling a new __vc_resize() which implements the above.

This patch makes the situation much more obvious.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-8-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/vt.c

@@ -1115,13 +1115,13 @@ int vc_allocate(unsigned int currcons)	/* return 0 on success */
 }
 
 static inline int resize_screen(struct vc_data *vc, int width, int height,
-				int user)
+				bool from_user)
 {
 	/* Resizes the resolution of the display adapater */
 	int err = 0;
 
 	if (vc->vc_sw->con_resize)
-		err = vc->vc_sw->con_resize(vc, width, height, user);
+		err = vc->vc_sw->con_resize(vc, width, height, from_user);
 
 	return err;
 }
@@ -1132,6 +1132,7 @@ static inline int resize_screen(struct vc_data *vc, int width, int height,
  *	@vc: virtual console private data
  *	@cols: columns
  *	@lines: lines
+ *	@from_user: invoked by a user?
  *
  *	Resize a virtual console, clipping according to the actual constraints.
  *	If the caller passes a tty structure then update the termios winsize
@@ -1142,21 +1143,17 @@ static inline int resize_screen(struct vc_data *vc, int width, int height,
  */
 
 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
-				unsigned int cols, unsigned int lines)
+			unsigned int cols, unsigned int lines, bool from_user)
 {
 	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
 	unsigned long end;
 	unsigned int old_rows, old_row_size, first_copied_row;
 	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
-	unsigned int user;
 	unsigned short *oldscreen, *newscreen;
 	u32 **new_uniscr = NULL;
 
 	WARN_CONSOLE_UNLOCKED();
 
-	user = vc->vc_resize_user;
-	vc->vc_resize_user = 0;
-
 	if (cols > VC_MAXCOL || lines > VC_MAXROW)
 		return -EINVAL;
 
@@ -1182,7 +1179,7 @@ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
 		 * to deal with possible errors from the code below, we call
 		 * the resize_screen here as well.
 		 */
-		return resize_screen(vc, new_cols, new_rows, user);
+		return resize_screen(vc, new_cols, new_rows, from_user);
 	}
 
 	if (new_screen_size > KMALLOC_MAX_SIZE || !new_screen_size)
@@ -1205,7 +1202,7 @@ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
 	old_rows = vc->vc_rows;
 	old_row_size = vc->vc_size_row;
 
-	err = resize_screen(vc, new_cols, new_rows, user);
+	err = resize_screen(vc, new_cols, new_rows, from_user);
 	if (err) {
 		kfree(newscreen);
 		vc_uniscr_free(new_uniscr);
@@ -1292,22 +1289,23 @@ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
 }
 
 /**
- *	vc_resize		-	resize a VT
+ *	__vc_resize		-	resize a VT
  *	@vc: virtual console
  *	@cols: columns
  *	@rows: rows
+ *	@from_user: invoked by a user?
  *
  *	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->port.tty
  */
-
-int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
+int __vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows,
+		bool from_user)
 {
-	return vc_do_resize(vc->port.tty, vc, cols, rows);
+	return vc_do_resize(vc->port.tty, vc, cols, rows, from_user);
 }
-EXPORT_SYMBOL(vc_resize);
+EXPORT_SYMBOL(__vc_resize);
 
 /**
  *	vt_resize		-	resize a VT
@@ -1327,7 +1325,7 @@ static int vt_resize(struct tty_struct *tty, struct winsize *ws)
 	int ret;
 
 	console_lock();
-	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
+	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row, false);
 	console_unlock();
 	return ret;
 }

drivers/tty/vt/vt_ioctl.c

@@ -714,8 +714,7 @@ static int vt_resizex(struct vc_data *vc, struct vt_consize __user *cs)
 				vcp->vc_scan_lines = v.v_vlin;
 			if (v.v_clin)
 				vcp->vc_cell_height = v.v_clin;
-			vcp->vc_resize_user = 1;
-			ret = vc_resize(vcp, v.v_cols, v.v_rows);
+			ret = __vc_resize(vcp, v.v_cols, v.v_rows, true);
 			if (ret) {
 				vcp->vc_scan_lines = save_scan_lines;
 				vcp->vc_cell_height = save_cell_height;
@@ -923,9 +922,8 @@ int vt_ioctl(struct tty_struct *tty,
 			vc = vc_cons[i].d;
 
 			if (vc) {
-				vc->vc_resize_user = 1;
 				/* FIXME: review v tty lock */
-				vc_resize(vc_cons[i].d, cc, ll);
+				__vc_resize(vc_cons[i].d, cc, ll, true);
 			}
 		}
 		console_unlock();

drivers/video/console/vgacon.c

@@ -1081,12 +1081,12 @@ static int vgacon_font_get(struct vc_data *c, struct console_font *font, unsigne
 }
 
 static int vgacon_resize(struct vc_data *c, unsigned int width,
-			 unsigned int height, unsigned int user)
+			 unsigned int height, bool from_user)
 {
 	if ((width << 1) * height > vga_vram_size)
 		return -EINVAL;
 
-	if (user) {
+	if (from_user) {
 		/*
 		 * Ho ho!  Someone (svgatextmode, eh?) may have reprogrammed
 		 * the video mode!  Set the new defaults then and go away.

drivers/video/fbdev/core/fbcon.c

@@ -1996,7 +1996,7 @@ static void updatescrollmode(struct fbcon_display *p,
 #define CALC_FONTSZ(h, p, c) ((h) * (p) * (c)) /* size = height * pitch * charcount */
 
 static int fbcon_resize(struct vc_data *vc, unsigned int width,
-			unsigned int height, unsigned int user)
+			unsigned int height, bool from_user)
 {
 	struct fb_info *info = fbcon_info_from_console(vc->vc_num);
 	struct fbcon_ops *ops = info->fbcon_par;

include/linux/console.h

@@ -66,7 +66,7 @@ struct consw {
 	int	(*con_font_default)(struct vc_data *vc,
 			struct console_font *font, char *name);
 	int     (*con_resize)(struct vc_data *vc, unsigned int width,
-			unsigned int height, unsigned int user);
+			      unsigned int height, bool from_user);
 	void	(*con_set_palette)(struct vc_data *vc,
 			const unsigned char *table);
 	void	(*con_scrolldelta)(struct vc_data *vc, int lines);

include/linux/console_struct.h

@@ -151,7 +151,6 @@ struct vc_data {
 	DECLARE_BITMAP(vc_tab_stop, VC_TABSTOPS_COUNT);	/* Tab stops. 256 columns. */
 	unsigned char   vc_palette[16*3];       /* Colour palette for VGA+ */
 	unsigned short * vc_translate;
-	unsigned int    vc_resize_user;         /* resize request from user */
 	unsigned int	vc_bell_pitch;		/* Console bell pitch */
 	unsigned int	vc_bell_duration;	/* Console bell duration */
 	unsigned short	vc_cur_blink_ms;	/* Cursor blink duration */

include/linux/vt_kern.h

@@ -25,7 +25,8 @@ 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_resize(struct vc_data *vc, unsigned int cols, unsigned int lines,
+		bool from_user);
 struct vc_data *vc_deallocate(unsigned int console);
 void reset_palette(struct vc_data *vc);
 void do_blank_screen(int entering_gfx);
@@ -42,6 +43,12 @@ void redraw_screen(struct vc_data *vc, int is_switch);
 #define update_screen(x) redraw_screen(x, 0)
 #define switch_screen(x) redraw_screen(x, 1)
 
+static inline int vc_resize(struct vc_data *vc, unsigned int cols,
+			    unsigned int lines)
+{
+	return __vc_resize(vc, cols, lines, false);
+}
+
 struct tty_struct;
 int tioclinux(struct tty_struct *tty, unsigned long arg);