[PATCH] con_font_op split

Preparations for cleanups: con_font_op() is turned into a switch calling
con_font_{get,set,default,copy} depending on the operation required;
method ->con_font_op() also split, with NULL resulting in -ENOSYS on
operation in question.

Code that used to be in con_font_op() got slightly cleaned up after move
into new helpers (we are beginning to untangle the mess; there will be
more cleanups in the next patches).

Methods are currently using exact same arguments as old ->con_font_op().
That will change in subsequent patches, method by method (right now there's
a hell of a scary field reuse between them, making impossible to do any
static checks and practically begging for bugs).
Signed-off-by: Al Viro <viro@parcelfarce.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/vt.c

@@ -3023,21 +3023,75 @@ void reset_palette(int currcons)
 
 #define max_font_size 65536
 
-int con_font_op(int currcons, struct console_font_op *op)
+int con_font_get(int currcons, struct console_font_op *op)
 {
+	struct console_font_op old_op;
 	int rc = -EINVAL;
-	int size = max_font_size, set;
 	u8 *temp = NULL;
+	int c;
+
+	if (vt_cons[currcons]->vc_mode != KD_TEXT)
+		return -EINVAL;
+
+	memcpy(&old_op, op, sizeof(old_op));
+	if (op->data) {
+		temp = kmalloc(max_font_size, GFP_KERNEL);
+		if (!temp)
+			return -ENOMEM;
+		op->data = temp;
+	}
+
+	acquire_console_sem();
+	if (sw->con_font_get)
+		rc = sw->con_font_get(vc_cons[currcons].d, op);
+	else
+		rc = -ENOSYS;
+	release_console_sem();
+
+	op->data = old_op.data;
+	if (rc)
+		goto out;
+
+	c = (op->width+7)/8 * 32 * op->charcount;
+	
+	if (op->data && op->charcount > old_op.charcount)
+		rc = -ENOSPC;
+	if (!(op->flags & KD_FONT_FLAG_OLD)) {
+		if (op->width > old_op.width || 
+		    op->height > old_op.height) 
+			rc = -ENOSPC;
+	} else {
+		if (op->width != 8)
+			rc = -EIO;
+		else if ((old_op.height && op->height > old_op.height) ||
+			 op->height > 32)
+			rc = -ENOSPC;
+	}
+	if (rc)
+		goto out;
+
+	if (op->data && copy_to_user(op->data, temp, c))
+		rc = -EFAULT;
+
+out:
+	kfree(temp);
+	return rc;
+}
+
+int con_font_set(int currcons, struct console_font_op *op)
+{
 	struct console_font_op old_op;
+	int rc = -EINVAL;
+	int size;
+	u8 *temp;
 
 	if (vt_cons[currcons]->vc_mode != KD_TEXT)
-		goto quit;
+		return -EINVAL;
 	memcpy(&old_op, op, sizeof(old_op));
-	if (op->op == KD_FONT_OP_SET) {
 	if (!op->data)
 		return -EINVAL;
 	if (op->charcount > 512)
-			goto quit;
+		return -EINVAL;
 	if (!op->height) {		/* Need to guess font height [compat] */
 		int h, i;
 		u8 __user *charmap = op->data;
@@ -3046,75 +3100,90 @@ int con_font_op(int currcons, struct console_font_op *op)
 		/* If from KDFONTOP ioctl, don't allow things which can be done in userland,
 		   so that we can get rid of this soon */
 		if (!(op->flags & KD_FONT_FLAG_OLD))
-				goto quit;
-			rc = -EFAULT;
+			return -EINVAL;
 		for (h = 32; h > 0; h--)
 			for (i = 0; i < op->charcount; i++) {
 				if (get_user(tmp, &charmap[32*i+h-1]))
-						goto quit;
+					return -EFAULT;
 				if (tmp)
 					goto nonzero;
 			}
-			rc = -EINVAL;
-			goto quit;
+		return -EINVAL;
 	nonzero:
-			rc = -EINVAL;
 		op->height = h;
 	}
 	if (op->width > 32 || op->height > 32)
-			goto quit;
+		return -EINVAL;
 	size = (op->width+7)/8 * 32 * op->charcount;
 	if (size > max_font_size)
 		return -ENOSPC;
-		set = 1;
-	} else if (op->op == KD_FONT_OP_GET)
-		set = 0;
-	else {
-		acquire_console_sem();
-		rc = sw->con_font_op(vc_cons[currcons].d, op);
-		release_console_sem();
-		return rc;
-	}
-	if (op->data) {
 	temp = kmalloc(size, GFP_KERNEL);
 	if (!temp)
 		return -ENOMEM;
-		if (set && copy_from_user(temp, op->data, size)) {
+	if (copy_from_user(temp, op->data, size)) {
 		rc = -EFAULT;
-			goto quit;
+		goto out;
 	}
 	op->data = temp;
-	}
+	acquire_console_sem();
+	if (sw->con_font_set)
+		rc = sw->con_font_set(vc_cons[currcons].d, op);
+	else
+		rc = -ENOSYS;
+	release_console_sem();
+	op->data = old_op.data;
+out:
+	kfree(temp);
+	return rc;
+}
+
+int con_font_default(int currcons, struct console_font_op *op)
+{
+	int rc;
+
+	if (vt_cons[currcons]->vc_mode != KD_TEXT)
+		return -EINVAL;
 
 	acquire_console_sem();
-	rc = sw->con_font_op(vc_cons[currcons].d, op);
+	if (sw->con_font_default)
+		rc = sw->con_font_default(vc_cons[currcons].d, op);
+	else
+		rc = -ENOSYS;
 	release_console_sem();
+	return rc;
+}
 
-	op->data = old_op.data;
-	if (!rc && !set) {
-		int c = (op->width+7)/8 * 32 * op->charcount;
+int con_font_copy(int currcons, struct console_font_op *op)
+{
+	int rc;
 
-		if (op->data && op->charcount > old_op.charcount)
-			rc = -ENOSPC;
-		if (!(op->flags & KD_FONT_FLAG_OLD)) {
-			if (op->width > old_op.width || 
-			    op->height > old_op.height)
-				rc = -ENOSPC;
-		} else {
-			if (op->width != 8)
-				rc = -EIO;
-			else if ((old_op.height && op->height > old_op.height) ||
-			         op->height > 32)
-				rc = -ENOSPC;
-		}
-		if (!rc && op->data && copy_to_user(op->data, temp, c))
-			rc = -EFAULT;
-	}
-quit:	if (temp)
-		kfree(temp);
+	if (vt_cons[currcons]->vc_mode != KD_TEXT)
+		return -EINVAL;
+
+	acquire_console_sem();
+	if (sw->con_font_copy)
+		rc = sw->con_font_copy(vc_cons[currcons].d, op);
+	else
+		rc = -ENOSYS;
+	release_console_sem();
 	return rc;
 }
 
+int con_font_op(int currcons, struct console_font_op *op)
+{
+	switch (op->op) {
+	case KD_FONT_OP_SET:
+		return con_font_set(currcons, op);
+	case KD_FONT_OP_GET:
+		return con_font_get(currcons, op);
+	case KD_FONT_OP_SET_DEFAULT:
+		return con_font_default(currcons, op);
+	case KD_FONT_OP_COPY:
+		return con_font_copy(currcons, op);
+	}
+	return -ENOSYS;
+}
+
 /*
  *	Interface exported to selection and vcs.
  */

drivers/video/console/dummycon.c

@@ -71,7 +71,10 @@ const struct consw dummy_con = {
     .con_bmove =	DUMMY,
     .con_switch =	DUMMY,
     .con_blank =	DUMMY,
-    .con_font_op =	DUMMY,
+    .con_font_set =	DUMMY,
+    .con_font_get =	DUMMY,
+    .con_font_default =	DUMMY,
+    .con_font_copy =	DUMMY,
     .con_set_palette =	DUMMY,
     .con_scrolldelta =	DUMMY,
 };

drivers/video/console/fbcon.c

@@ -165,7 +165,6 @@ static void fbcon_bmove(struct vc_data *vc, int sy, int sx, int dy, int dx,
 			int height, int width);
 static int fbcon_switch(struct vc_data *vc);
 static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch);
-static int fbcon_font_op(struct vc_data *vc, struct console_font_op *op);
 static int fbcon_set_palette(struct vc_data *vc, unsigned char *table);
 static int fbcon_scrolldelta(struct vc_data *vc, int lines);
 void accel_clear_margins(struct vc_data *vc, struct fb_info *info,
@@ -2001,7 +2000,7 @@ static void fbcon_free_font(struct display *p)
 	p->userfont = 0;
 }
 
-static inline int fbcon_get_font(struct vc_data *vc, struct console_font_op *op)
+static int fbcon_get_font(struct vc_data *vc, struct console_font_op *op)
 {
 	u8 *fontdata = vc->vc_font.data;
 	u8 *data = op->data;
@@ -2168,7 +2167,7 @@ static int fbcon_do_set_font(struct vc_data *vc, struct console_font_op *op,
 	return 0;
 }
 
-static inline int fbcon_copy_font(struct vc_data *vc, struct console_font_op *op)
+static int fbcon_copy_font(struct vc_data *vc, struct console_font_op *op)
 {
 	struct display *od;
 	int h = op->height;
@@ -2185,7 +2184,7 @@ static inline int fbcon_copy_font(struct vc_data *vc, struct console_font_op *op
 	return fbcon_do_set_font(vc, op, od->fontdata, od->userfont);
 }
 
-static inline int fbcon_set_font(struct vc_data *vc, struct console_font_op *op)
+static int fbcon_set_font(struct vc_data *vc, struct console_font_op *op)
 {
 	int w = op->width;
 	int h = op->height;
@@ -2273,7 +2272,7 @@ static inline int fbcon_set_font(struct vc_data *vc, struct console_font_op *op)
 	return fbcon_do_set_font(vc, op, new_data, 1);
 }
 
-static inline int fbcon_set_def_font(struct vc_data *vc, struct console_font_op *op)
+static int fbcon_set_def_font(struct vc_data *vc, struct console_font_op *op)
 {
 	struct fb_info *info = registered_fb[(int) con2fb_map[vc->vc_num]];
 	char name[MAX_FONT_NAME];
@@ -2293,22 +2292,6 @@ static inline int fbcon_set_def_font(struct vc_data *vc, struct console_font_op
 	return fbcon_do_set_font(vc, op, f->data, 0);
 }
 
-static int fbcon_font_op(struct vc_data *vc, struct console_font_op *op)
-{
-	switch (op->op) {
-	case KD_FONT_OP_SET:
-		return fbcon_set_font(vc, op);
-	case KD_FONT_OP_GET:
-		return fbcon_get_font(vc, op);
-	case KD_FONT_OP_SET_DEFAULT:
-		return fbcon_set_def_font(vc, op);
-	case KD_FONT_OP_COPY:
-		return fbcon_copy_font(vc, op);
-	default:
-		return -ENOSYS;
-	}
-}
-
 static u16 palette_red[16];
 static u16 palette_green[16];
 static u16 palette_blue[16];
@@ -2609,7 +2592,10 @@ const struct consw fb_con = {
 	.con_bmove 		= fbcon_bmove,
 	.con_switch 		= fbcon_switch,
 	.con_blank 		= fbcon_blank,
-	.con_font_op 		= fbcon_font_op,
+	.con_font_set 		= fbcon_set_font,
+	.con_font_get 		= fbcon_get_font,
+	.con_font_default	= fbcon_set_def_font,
+	.con_font_copy 		= fbcon_copy_font,
 	.con_set_palette 	= fbcon_set_palette,
 	.con_scrolldelta 	= fbcon_scrolldelta,
 	.con_set_origin 	= fbcon_set_origin,

drivers/video/console/mdacon.c

@@ -517,11 +517,6 @@ static int mdacon_blank(struct vc_data *c, int blank, int mode_switch)
 	}
 }
 
-static int mdacon_font_op(struct vc_data *c, struct console_font_op *op)
-{
-	return -ENOSYS;
-}
-
 static int mdacon_scrolldelta(struct vc_data *c, int lines)
 {
 	return 0;
@@ -594,7 +589,6 @@ const struct consw mda_con = {
 	.con_bmove =		mdacon_bmove,
 	.con_switch =		mdacon_switch,
 	.con_blank =		mdacon_blank,
-	.con_font_op =		mdacon_font_op,
 	.con_set_palette =	mdacon_set_palette,
 	.con_scrolldelta =	mdacon_scrolldelta,
 	.con_build_attr =	mdacon_build_attr,

drivers/video/console/newport_con.c

@@ -543,18 +543,14 @@ static int newport_set_def_font(int unit, struct console_font_op *op)
 	return 0;
 }
 
-static int newport_font_op(struct vc_data *vc, struct console_font_op *op)
+static int newport_font_default(struct vc_data *vc, struct console_font_op *op)
 {
-	int unit = vc->vc_num;
+	return newport_set_def_font(vc->vc_num, op);
+}
 
-	switch (op->op) {
-	case KD_FONT_OP_SET:
-		return newport_set_font(unit, op);
-	case KD_FONT_OP_SET_DEFAULT:
-		return newport_set_def_font(unit, op);
-	default:
-		return -ENOSYS;
-	}
+static int newport_font_set(struct vc_data *vc, struct console_font_op *op)
+{
+	return newport_set_font(vc->vc_num, op);
 }
 
 static int newport_set_palette(struct vc_data *vc, unsigned char *table)
@@ -717,7 +713,8 @@ const struct consw newport_con = {
     .con_bmove =	newport_bmove,
     .con_switch =	newport_switch,
     .con_blank =	newport_blank,
-    .con_font_op =	newport_font_op,
+    .con_font_set =	newport_font_set,
+    .con_font_default =	newport_font_default,
     .con_set_palette =	newport_set_palette,
     .con_scrolldelta =	newport_scrolldelta,
     .con_set_origin =	DUMMY,

drivers/video/console/promcon.c

@@ -456,12 +456,6 @@ promcon_cursor(struct vc_data *conp, int mode)
 	}
 }
 
-static int
-promcon_font_op(struct vc_data *conp, struct console_font_op *op)
-{
-	return -ENOSYS;
-}
-        
 static int
 promcon_blank(struct vc_data *conp, int blank, int mode_switch)
 {
@@ -586,7 +580,6 @@ const struct consw prom_con = {
 	.con_bmove =		promcon_bmove,
 	.con_switch =		promcon_switch,
 	.con_blank =		promcon_blank,
-	.con_font_op =		promcon_font_op,
 	.con_set_palette =	DUMMY,
 	.con_scrolldelta =	DUMMY,
 #if !(PROMCON_COLOR)

drivers/video/console/sticon.c

@@ -85,11 +85,6 @@ static int sticon_set_palette(struct vc_data *c, unsigned char *table)
     return -EINVAL;
 }
 
-static int sticon_font_op(struct vc_data *c, struct console_font_op *op)
-{
-    return -ENOSYS;
-}
-
 static void sticon_putc(struct vc_data *conp, int c, int ypos, int xpos)
 {
     int unit = conp->vc_num;
@@ -366,7 +361,6 @@ static struct consw sti_con = {
 	.con_bmove		= sticon_bmove,
 	.con_switch		= sticon_switch,
 	.con_blank		= sticon_blank,
-	.con_font_op		= sticon_font_op,
 	.con_set_palette	= sticon_set_palette,
 	.con_scrolldelta	= sticon_scrolldelta,
 	.con_set_origin		= sticon_set_origin,

drivers/video/console/vgacon.c

@@ -77,7 +77,6 @@ static void vgacon_deinit(struct vc_data *c);
 static void vgacon_cursor(struct vc_data *c, int mode);
 static int vgacon_switch(struct vc_data *c);
 static int vgacon_blank(struct vc_data *c, int blank, int mode_switch);
-static int vgacon_font_op(struct vc_data *c, struct console_font_op *op);
 static int vgacon_set_palette(struct vc_data *vc, unsigned char *table);
 static int vgacon_scrolldelta(struct vc_data *c, int lines);
 static int vgacon_set_origin(struct vc_data *c);
@@ -908,38 +907,42 @@ static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight)
 	return 0;
 }
 
-static int vgacon_font_op(struct vc_data *c, struct console_font_op *op)
+static int vgacon_font_set(struct vc_data *c, struct console_font_op *op)
 {
 	int rc;
 
 	if (vga_video_type < VIDEO_TYPE_EGAM)
 		return -EINVAL;
 
-	if (op->op == KD_FONT_OP_SET) {
-		if (op->width != 8
-		    || (op->charcount != 256 && op->charcount != 512))
+	if (op->width != 8 || (op->charcount != 256 && op->charcount != 512))
 		return -EINVAL;
+
 	rc = vgacon_do_font_op(&state, op->data, 1, op->charcount == 512);
-		if (!rc && !(op->flags & KD_FONT_FLAG_DONT_RECALC))
+	if (rc)
+		return rc;
+
+	if (!(op->flags & KD_FONT_FLAG_DONT_RECALC))
 		rc = vgacon_adjust_height(c, op->height);
-	} else if (op->op == KD_FONT_OP_GET) {
+	return rc;
+}
+
+static int vgacon_font_get(struct vc_data *c, struct console_font_op *op)
+{
+	if (vga_video_type < VIDEO_TYPE_EGAM)
+		return -EINVAL;
+
 	op->width = 8;
 	op->height = c->vc_font.height;
 	op->charcount = vga_512_chars ? 512 : 256;
 	if (!op->data)
 		return 0;
-		rc = vgacon_do_font_op(&state, op->data, 0, 0);
-	} else
-		rc = -ENOSYS;
-	return rc;
+	return vgacon_do_font_op(&state, op->data, 0, 0);
 }
 
 #else
 
-static int vgacon_font_op(struct vc_data *c, struct console_font_op *op)
-{
-	return -ENOSYS;
-}
+#define vgacon_font_set NULL
+#define vgacon_font_get NULL
 
 #endif
 
@@ -1079,7 +1082,8 @@ const struct consw vga_con = {
 	.con_bmove = DUMMY,
 	.con_switch = vgacon_switch,
 	.con_blank = vgacon_blank,
-	.con_font_op = vgacon_font_op,
+	.con_font_set = vgacon_font_set,
+	.con_font_get = vgacon_font_get,
 	.con_set_palette = vgacon_set_palette,
 	.con_scrolldelta = vgacon_scrolldelta,
 	.con_set_origin = vgacon_set_origin,

include/linux/console.h

@@ -40,7 +40,10 @@ struct consw {
 	void	(*con_bmove)(struct vc_data *, int, int, int, int, int, int);
 	int	(*con_switch)(struct vc_data *);
 	int	(*con_blank)(struct vc_data *, int, int);
-	int	(*con_font_op)(struct vc_data *, struct console_font_op *);
+	int	(*con_font_set)(struct vc_data *, struct console_font_op *);
+	int	(*con_font_get)(struct vc_data *, struct console_font_op *);
+	int	(*con_font_default)(struct vc_data *, struct console_font_op *);
+	int	(*con_font_copy)(struct vc_data *, struct console_font_op *);
 	int	(*con_resize)(struct vc_data *, unsigned int, unsigned int);
 	int	(*con_set_palette)(struct vc_data *, unsigned char *);
 	int	(*con_scrolldelta)(struct vc_data *, int);

include/linux/vt_kern.h

@@ -50,6 +50,10 @@ void do_unblank_screen(int leaving_gfx);
 void unblank_screen(void);
 void poke_blanked_console(void);
 int con_font_op(int currcons, struct console_font_op *op);
+int con_font_set(int currcons, struct console_font_op *op);
+int con_font_get(int currcons, struct console_font_op *op);
+int con_font_default(int currcons, struct console_font_op *op);
+int con_font_copy(int currcons, struct console_font_op *op);
 int con_set_cmap(unsigned char __user *cmap);
 int con_get_cmap(unsigned char __user *cmap);
 void scrollback(int);