vt: Store font in struct vc_font

Replace struct console_font with struct vc_font for the type of the
vc_font field of struct vc_data. Struct console_font is UAPI, which
prevents further changes. Hence a new data type is required.

Struct console_font has a documented vertical pitch of 32 bytes. This
is not the case after the font data has been loaded into the kernel.
Changing the type of vc_font addresses this inconsistency.

The font data is now declared as constant, as it might come from the
kernel's read-only section. There's some fallout throughout the console
code where non-const variables refer to it. Fix them. A later update
will declare the font data to a dedicated data type.

v3:
- fix typos

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/drivers/video/fbdev/core/bitblit.c b/drivers/video/fbdev/core/bitblit.c
index 085ffb44c51a91a622614708e40656e6789224d2..7478accea8ecf0770e8eb2113779f82f8ae30e9b 100644 (file)
--- a/drivers/video/fbdev/core/bitblit.c
+++ b/drivers/video/fbdev/core/bitblit.c
@@ -22,8 +22,7 @@
 /*
  * Accelerated handlers.
  */
-static void update_attr(u8 *dst, u8 *src, int attribute,
-                              struct vc_data *vc)
+static void update_attr(u8 *dst, const u8 *src, int attribute, struct vc_data *vc)
 {
        int i, offset = (vc->vc_font.height < 10) ? 1 : 2;
        int width = DIV_ROUND_UP(vc->vc_font.width, 8);
@@ -81,7 +80,7 @@ static inline void bit_putcs_aligned(struct vc_data *vc, struct fb_info *info,
        u16 charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
        unsigned int charcnt = vc->vc_font.charcount;
        u32 idx = vc->vc_font.width >> 3;
-       u8 *src;
+       const u8 *src;
 
        while (cnt--) {
                u16 ch = scr_readw(s++) & charmask;
@@ -120,7 +119,7 @@ static inline void bit_putcs_unaligned(struct vc_data *vc,
        u32 shift_low = 0, mod = vc->vc_font.width % 8;
        u32 shift_high = 8;
        u32 idx = vc->vc_font.width >> 3;
-       u8 *src;
+       const u8 *src;
 
        while (cnt--) {
                u16 ch = scr_readw(s++) & charmask;
@@ -267,7 +266,7 @@ static void bit_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
        int y = real_y(par->p, vc->state.y);
        int attribute, use_sw = vc->vc_cursor_type & CUR_SW;
        int err = 1;
-       char *src;
+       const u8 *src;
 
        cursor.set = 0;
 
@@ -278,7 +277,7 @@ static void bit_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
        attribute = get_attribute(info, c);
        src = vc->vc_font.data + ((c & charmask) * (w * vc->vc_font.height));
 
-       if (par->cursor_state.image.data != src ||
+       if (par->cursor_state.image.data != (const char *)src ||
            par->cursor_reset) {
                par->cursor_state.image.data = src;
                cursor.set |= FB_CUR_SETIMAGE;

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 666261ae59d82ca49aae526feee99e0ce1ede06c..247bb90c08d347cf9d80312c079ee525301d11a4 100644 (file)
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2286,7 +2286,7 @@ static bool fbcon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
 
 static int fbcon_get_font(struct vc_data *vc, struct console_font *font, unsigned int vpitch)
 {
-       u8 *fontdata = vc->vc_font.data;
+       const u8 *fontdata = vc->vc_font.data;
        u8 *data = font->data;
        int i, j;
 
@@ -2417,7 +2417,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h, int charcount,
        struct fbcon_par *par = info->fbcon_par;
        struct fbcon_display *p = &fb_display[vc->vc_num];
        int resize, ret, old_userfont, old_width, old_height, old_charcount;
-       u8 *old_data = vc->vc_font.data;
+       const u8 *old_data = vc->vc_font.data;
 
        resize = (w != vc->vc_font.width) || (h != vc->vc_font.height);
        vc->vc_font.data = (void *)(p->fontdata = data);

diff --git a/drivers/video/fbdev/core/fbcon.h b/drivers/video/fbdev/core/fbcon.h
index fca14e9b729b974b1b792d0cdb4da7ca2f8f40b3..3f4386a402374426f42e13e7566f9a343c62e363 100644 (file)
--- a/drivers/video/fbdev/core/fbcon.h
+++ b/drivers/video/fbdev/core/fbcon.h
@@ -82,8 +82,8 @@ struct fbcon_par {
        int    rotate;
        int    cur_rotate;
        char  *cursor_data;
-       u8    *fontbuffer;
-       u8    *fontdata;
+       u8          *fontbuffer;
+       const u8    *fontdata;
        u8    *cursor_src;
        u32    cursor_size;
        u32    fd_size;

diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h
index ebdb9750d348f9d067c6aae67851c3e8dc95901a..ea0cdf4278a3fd04de224a30ae119e16519985b7 100644 (file)
--- a/include/linux/console_struct.h
+++ b/include/linux/console_struct.h
@@ -13,8 +13,9 @@
 #ifndef _LINUX_CONSOLE_STRUCT_H
 #define _LINUX_CONSOLE_STRUCT_H
 
-#include <linux/wait.h>
+#include <linux/math.h>
 #include <linux/vt.h>
+#include <linux/wait.h>
 #include <linux/workqueue.h>
 
 struct uni_pagedict;
@@ -58,6 +59,30 @@ struct vc_state {
        bool            reverse;
 };
 
+/**
+ * struct vc_font - Describes a font
+ * @width: The width of a single glyph in bits
+ * @height: The height of a single glyph in scanlines
+ * @charcount: The number of glyphs in the font
+ * @data: The raw font data
+ *
+ * Font data is organized as an array of glyphs. Each glyph is a bitmap with
+ * set bits indicating the foreground color. Unset bits indicate background
+ * color. The fields @width and @height store a single glyph's number of
+ * horizontal bits and vertical scanlines. If width is not a multiple of 8,
+ * there are trailing bits to fill up the byte. These bits should not be drawn.
+ *
+ * The field @data points to the first glyph's first byte. The value @charcount
+ * gives the number of glyphs in the font. There are no empty scanlines between
+ * two adjacent glyphs.
+ */
+struct vc_font {
+       unsigned int width;
+       unsigned int height;
+       unsigned int charcount;
+       const unsigned char *data;
+};
+
 /*
  * Example: vc_data of a console that was scrolled 3 lines down.
  *
@@ -122,7 +147,7 @@ struct vc_data {
        unsigned long   vc_pos;                 /* Cursor address */
        /* fonts */
        unsigned short  vc_hi_font_mask;        /* [#] Attribute set for upper 256 chars of font or 0 if not supported */
-       struct console_font vc_font;            /* Current VC font set */
+       struct vc_font vc_font;                 /* Current VC font set */
        unsigned short  vc_video_erase_char;    /* Background erase character */
        /* VT terminal data */
        unsigned int    vc_state;               /* Escape sequence parser state */