[PATCH 00/10] fbcon,fonts: Refactor framebuffer console rotation

[PATCH 00/10] fbcon,fonts: Refactor framebuffer console rotation

[Thomas Zimmermann]

Refactor the framebuffer console rotation into individual components
for glyphs, fonts and the overall fbcon state. Right now this is mixed
up in fbcon_rotate.{c,h}. Also build cursor rotation on top of the new
interfaces.

Start with an OOB fix in patch 1. If buffer allocation fails, fbcon
currently uses a too-small glyph buffer for output. Avoid that.

Patches 2 to 4 make a number of small improvements to the font library
and its callers.

Patches 5 to 8 refactor the font rotation. Fbcon rotation rotates each
individual glphy in a font buffer and uses the rotated buffer's glyphs
for output. The result looks like the console buffer has been rotated
as a whole. Split this into helpers that rotate individual glyphs and
a helper that rotates the font buffer of these. Then reimplement fbcon
rotation on top. Document the public font helpers.

Patch 9 rebuilds cursor rotation on top of the new glyph helpers. The
fbcon cursor is itself a glyph that has to be rotated in sync with the
font.

Patch 10 moves the state of fbcon rotation into a single place and makes
is a build-time conditional.

Tested with fbcon under bochs on Qemu.

Built upon the fbcon changes at [1].

[1] https://lore.kernel.org/linux-fbdev/20260309141723.137364-1-tzimmermann@suse.de/

Thomas Zimmermann (10):
  fbcon: Avoid OOB font access if console rotation fails
  vt: Implement helpers for struct vc_font in source file
  lib/fonts: Provide helpers for calculating glyph pitch and size
  lib/fonts: Clean up Makefile
  lib/fonts: Implement glyph rotation
  lib/fonts: Refactor glyph-pattern helpers
  lib/fonts: Refactor glyph-rotation helpers
  lib/fonts: Implement font rotation
  fbcon: Fill cursor mask in helper function
  fbcon: Put font-rotation state into separate struct

 drivers/tty/vt/vt.c                     |  34 +++
 drivers/video/fbdev/core/bitblit.c      |  35 +--
 drivers/video/fbdev/core/fbcon.c        |  48 ++++-
 drivers/video/fbdev/core/fbcon.h        |  14 +-
 drivers/video/fbdev/core/fbcon_ccw.c    |  70 ++----
 drivers/video/fbdev/core/fbcon_cw.c     |  70 ++----
 drivers/video/fbdev/core/fbcon_rotate.c |  88 ++------
 drivers/video/fbdev/core/fbcon_rotate.h |  71 ------
 drivers/video/fbdev/core/fbcon_ud.c     |  67 ++----
 include/linux/console_struct.h          |  30 +--
 include/linux/font.h                    |  51 +++++
 lib/fonts/Makefile                      |  36 ++--
 lib/fonts/font_rotate.c                 | 275 ++++++++++++++++++++++++
 lib/fonts/fonts.c                       |   2 +-
 14 files changed, 525 insertions(+), 366 deletions(-)
 create mode 100644 lib/fonts/font_rotate.c

-- 
2.53.0

[PATCH 01/10] fbcon: Avoid OOB font access if console rotation fails

[Thomas Zimmermann]

Clear the font buffer if the reallocation during console rotation fails
in fbcon_rotate_font(). The putcs implementations for the rotated buffer
will return early in this case. See [1] for an example.

Currently, fbcon_rotate_font() keeps the old buffer, which is to small
for the rotated font. Printing to the rotated console with a high-enough
character code will overflow the font buffer.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 6cc50e1c5b57 ("[PATCH] fbcon: Console Rotation - Add support to rotate font bitmap")
Cc: <stable@vger.kernel.org> # v2.6.15+
Link: https://elixir.bootlin.com/linux/v6.19/source/drivers/video/fbdev/core/fbcon_ccw.c#L144 # [1]
---
 drivers/video/fbdev/core/fbcon_rotate.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index 1562a8f20b4f..5348f6c6f57c 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -46,6 +46,10 @@ int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 		info->fbops->fb_sync(info);
 
 	if (par->fd_size < d_cellsize * len) {
+		kfree(par->fontbuffer);
+		par->fontbuffer = NULL;
+		par->fd_size = 0;
+
 		dst = kmalloc_array(len, d_cellsize, GFP_KERNEL);
 
 		if (dst == NULL) {
@@ -54,7 +58,6 @@ int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 		}
 
 		par->fd_size = d_cellsize * len;
-		kfree(par->fontbuffer);
 		par->fontbuffer = dst;
 	}
 
-- 
2.53.0

[PATCH 02/10] vt: Implement helpers for struct vc_font in source file

[Thomas Zimmermann]

Move the helpers vc_font_pitch() and vc_font_size() from the VT
header file into source file. They are not called very often, so
there's no benefit in keeping them in the headers. Also avoids
including <liux/math.h> from the header.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/tty/vt/vt.c            | 35 ++++++++++++++++++++++++++++++++++
 include/linux/console_struct.h | 30 ++---------------------------
 2 files changed, 37 insertions(+), 28 deletions(-)

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index e2df99e3d458..3d89d30c9596 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -71,6 +71,7 @@
  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
  */
 
+#include <linux/math.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/sched/signal.h>
@@ -230,6 +231,40 @@ enum {
 	blank_vesa_wait,
 };
 
+/*
+ * struct vc_font
+ */
+
+/**
+ * vc_font_pitch - Calculates the number of bytes between two adjacent scanlines
+ * @font: The VC font
+ *
+ * Returns:
+ * The number of bytes between two adjacent scanlines in the font data
+ */
+unsigned int vc_font_pitch(const struct vc_font *font)
+{
+	return DIV_ROUND_UP(font->width, 8);
+}
+EXPORT_SYMBOL_GPL(vc_font_pitch);
+
+/**
+ * vc_font_size - Calculates the size of the font data in bytes
+ * @font: The VC font
+ *
+ * vc_font_size() calculates the number of bytes of font data in the
+ * font specified by @font. The function calculates the size from the
+ * font parameters.
+ *
+ * Returns:
+ * The size of the font data in bytes.
+ */
+unsigned int vc_font_size(const struct vc_font *font)
+{
+	return font->height * vc_font_pitch(font) * font->charcount;
+}
+EXPORT_SYMBOL_GPL(vc_font_size);
+
 /*
  * /sys/class/tty/tty0/
  *
diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h
index 6ce498b31855..fe915afdece5 100644
--- a/include/linux/console_struct.h
+++ b/include/linux/console_struct.h
@@ -13,7 +13,6 @@
 #ifndef _LINUX_CONSOLE_STRUCT_H
 #define _LINUX_CONSOLE_STRUCT_H
 
-#include <linux/math.h>
 #include <linux/vt.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
@@ -83,33 +82,8 @@ struct vc_font {
 	const unsigned char *data;
 };
 
-/**
- * vc_font_pitch - Calculates the number of bytes between two adjacent scanlines
- * @font: The VC font
- *
- * Returns:
- * The number of bytes between two adjacent scanlines in the font data
- */
-static inline unsigned int vc_font_pitch(const struct vc_font *font)
-{
-	return DIV_ROUND_UP(font->width, 8);
-}
-
-/**
- * vc_font_size - Calculates the size of the font data in bytes
- * @font: The VC font
- *
- * vc_font_size() calculates the number of bytes of font data in the
- * font specified by @font. The function calculates the size from the
- * font parameters.
- *
- * Returns:
- * The size of the font data in bytes.
- */
-static inline unsigned int vc_font_size(const struct vc_font *font)
-{
-	return font->height * vc_font_pitch(font) * font->charcount;
-}
+unsigned int vc_font_pitch(const struct vc_font *font);
+unsigned int vc_font_size(const struct vc_font *font);
 
 /*
  * Example: vc_data of a console that was scrolled 3 lines down.
-- 
2.53.0

[PATCH 03/10] lib/fonts: Provide helpers for calculating glyph pitch and size

[Thomas Zimmermann]

Implement pitch and size calculation for a single font glyph in the
new helpers font_glyph_pitch() and font_glyph_size(). Replace the
instances where the calculations are opencoded.

Note that in the case of fbcon console rotation, the parameters for
a glyph's width and height might be reversed. This is intentionally.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/tty/vt/vt.c                     |  5 ++--
 drivers/video/fbdev/core/fbcon_ccw.c    | 11 +++----
 drivers/video/fbdev/core/fbcon_cw.c     | 11 +++----
 drivers/video/fbdev/core/fbcon_rotate.c |  6 ++--
 drivers/video/fbdev/core/fbcon_ud.c     |  7 +++--
 include/linux/font.h                    | 40 +++++++++++++++++++++++++
 lib/fonts/fonts.c                       |  2 +-
 7 files changed, 61 insertions(+), 21 deletions(-)

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 3d89d30c9596..23b9683b52a5 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -71,7 +71,6 @@
  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
  */
 
-#include <linux/math.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/sched/signal.h>
@@ -244,7 +243,7 @@ enum {
  */
 unsigned int vc_font_pitch(const struct vc_font *font)
 {
-	return DIV_ROUND_UP(font->width, 8);
+	return font_glyph_pitch(font->width);
 }
 EXPORT_SYMBOL_GPL(vc_font_pitch);
 
@@ -261,7 +260,7 @@ EXPORT_SYMBOL_GPL(vc_font_pitch);
  */
 unsigned int vc_font_size(const struct vc_font *font)
 {
-	return font->height * vc_font_pitch(font) * font->charcount;
+	return font_glyph_size(font->width, font->height) * font->charcount;
 }
 EXPORT_SYMBOL_GPL(vc_font_size);
 
diff --git a/drivers/video/fbdev/core/fbcon_ccw.c b/drivers/video/fbdev/core/fbcon_ccw.c
index 2f394b5a17f7..96ef449ee6ac 100644
--- a/drivers/video/fbdev/core/fbcon_ccw.c
+++ b/drivers/video/fbdev/core/fbcon_ccw.c
@@ -26,7 +26,7 @@ static void ccw_update_attr(u8 *dst, u8 *src, int attribute,
 				  struct vc_data *vc)
 {
 	int i, j, offset = (vc->vc_font.height < 10) ? 1 : 2;
-	int width = (vc->vc_font.height + 7) >> 3;
+	int width = font_glyph_pitch(vc->vc_font.height);
 	int mod = vc->vc_font.height % 8;
 	u8 c, msk = ~(0xff << offset), msk1 = 0;
 
@@ -101,7 +101,7 @@ static inline void ccw_putcs_aligned(struct vc_data *vc, struct fb_info *info,
 {
 	struct fbcon_par *par = info->fbcon_par;
 	u16 charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
-	u32 idx = (vc->vc_font.height + 7) >> 3;
+	u32 idx = font_glyph_pitch(vc->vc_font.height);
 	u8 *src;
 
 	while (cnt--) {
@@ -131,7 +131,7 @@ static void ccw_putcs(struct vc_data *vc, struct fb_info *info,
 {
 	struct fb_image image;
 	struct fbcon_par *par = info->fbcon_par;
-	u32 width = (vc->vc_font.height + 7)/8;
+	u32 width = font_glyph_pitch(vc->vc_font.height);
 	u32 cellsize = width * vc->vc_font.width;
 	u32 maxcnt = info->pixmap.size/cellsize;
 	u32 scan_align = info->pixmap.scan_align - 1;
@@ -223,7 +223,8 @@ static void ccw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	struct fb_cursor cursor;
 	struct fbcon_par *par = info->fbcon_par;
 	unsigned short charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
-	int w = (vc->vc_font.height + 7) >> 3, c;
+	int w = font_glyph_pitch(vc->vc_font.height);
+	int c;
 	int y = real_y(par->p, vc->state.y);
 	int attribute, use_sw = vc->vc_cursor_type & CUR_SW;
 	int err = 1, dx, dy;
@@ -297,7 +298,7 @@ static void ccw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 		char *tmp, *mask = kmalloc_array(w, vc->vc_font.width,
 						 GFP_ATOMIC);
 		int cur_height, size, i = 0;
-		int width = (vc->vc_font.width + 7)/8;
+		int width = font_glyph_pitch(vc->vc_font.width);
 
 		if (!mask)
 			return;
diff --git a/drivers/video/fbdev/core/fbcon_cw.c b/drivers/video/fbdev/core/fbcon_cw.c
index 3c3ad3471ec4..ea712654edae 100644
--- a/drivers/video/fbdev/core/fbcon_cw.c
+++ b/drivers/video/fbdev/core/fbcon_cw.c
@@ -26,7 +26,7 @@ static void cw_update_attr(u8 *dst, u8 *src, int attribute,
 				  struct vc_data *vc)
 {
 	int i, j, offset = (vc->vc_font.height < 10) ? 1 : 2;
-	int width = (vc->vc_font.height + 7) >> 3;
+	int width = font_glyph_pitch(vc->vc_font.height);
 	u8 c, msk = ~(0xff >> offset);
 
 	for (i = 0; i < vc->vc_font.width; i++) {
@@ -86,7 +86,7 @@ static inline void cw_putcs_aligned(struct vc_data *vc, struct fb_info *info,
 {
 	struct fbcon_par *par = info->fbcon_par;
 	u16 charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
-	u32 idx = (vc->vc_font.height + 7) >> 3;
+	u32 idx = font_glyph_pitch(vc->vc_font.height);
 	u8 *src;
 
 	while (cnt--) {
@@ -116,7 +116,7 @@ static void cw_putcs(struct vc_data *vc, struct fb_info *info,
 {
 	struct fb_image image;
 	struct fbcon_par *par = info->fbcon_par;
-	u32 width = (vc->vc_font.height + 7)/8;
+	u32 width = font_glyph_pitch(vc->vc_font.height);
 	u32 cellsize = width * vc->vc_font.width;
 	u32 maxcnt = info->pixmap.size/cellsize;
 	u32 scan_align = info->pixmap.scan_align - 1;
@@ -206,7 +206,8 @@ static void cw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	struct fb_cursor cursor;
 	struct fbcon_par *par = info->fbcon_par;
 	unsigned short charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
-	int w = (vc->vc_font.height + 7) >> 3, c;
+	int w = font_glyph_pitch(vc->vc_font.height);
+	int c;
 	int y = real_y(par->p, vc->state.y);
 	int attribute, use_sw = vc->vc_cursor_type & CUR_SW;
 	int err = 1, dx, dy;
@@ -280,7 +281,7 @@ static void cw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 		char *tmp, *mask = kmalloc_array(w, vc->vc_font.width,
 						 GFP_ATOMIC);
 		int cur_height, size, i = 0;
-		int width = (vc->vc_font.width + 7)/8;
+		int width = font_glyph_pitch(vc->vc_font.width);
 
 		if (!mask)
 			return;
diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index 5348f6c6f57c..18575c5182db 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -33,14 +33,12 @@ int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 	src = par->fontdata = vc->vc_font.data;
 	par->cur_rotate = par->p->con_rotate;
 	len = vc->vc_font.charcount;
-	s_cellsize = ((vc->vc_font.width + 7)/8) *
-		vc->vc_font.height;
+	s_cellsize = font_glyph_size(vc->vc_font.width, vc->vc_font.height);
 	d_cellsize = s_cellsize;
 
 	if (par->rotate == FB_ROTATE_CW ||
 	    par->rotate == FB_ROTATE_CCW)
-		d_cellsize = ((vc->vc_font.height + 7)/8) *
-			vc->vc_font.width;
+		d_cellsize = font_glyph_size(vc->vc_font.height, vc->vc_font.width);
 
 	if (info->fbops->fb_sync)
 		info->fbops->fb_sync(info);
diff --git a/drivers/video/fbdev/core/fbcon_ud.c b/drivers/video/fbdev/core/fbcon_ud.c
index 6fc30cad5b19..f7cd89c42b01 100644
--- a/drivers/video/fbdev/core/fbcon_ud.c
+++ b/drivers/video/fbdev/core/fbcon_ud.c
@@ -26,7 +26,7 @@ static void ud_update_attr(u8 *dst, u8 *src, int attribute,
 				  struct vc_data *vc)
 {
 	int i, offset = (vc->vc_font.height < 10) ? 1 : 2;
-	int width = (vc->vc_font.width + 7) >> 3;
+	int width = font_glyph_pitch(vc->vc_font.width);
 	unsigned int cellsize = vc->vc_font.height * width;
 	u8 c;
 
@@ -153,7 +153,7 @@ static void ud_putcs(struct vc_data *vc, struct fb_info *info,
 {
 	struct fb_image image;
 	struct fbcon_par *par = info->fbcon_par;
-	u32 width = (vc->vc_font.width + 7)/8;
+	u32 width = font_glyph_pitch(vc->vc_font.width);
 	u32 cellsize = width * vc->vc_font.height;
 	u32 maxcnt = info->pixmap.size/cellsize;
 	u32 scan_align = info->pixmap.scan_align - 1;
@@ -253,7 +253,8 @@ static void ud_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	struct fb_cursor cursor;
 	struct fbcon_par *par = info->fbcon_par;
 	unsigned short charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;
-	int w = (vc->vc_font.width + 7) >> 3, c;
+	int w = font_glyph_pitch(vc->vc_font.width);
+	int c;
 	int y = real_y(par->p, vc->state.y);
 	int attribute, use_sw = vc->vc_cursor_type & CUR_SW;
 	int err = 1, dx, dy;
diff --git a/include/linux/font.h b/include/linux/font.h
index 5401f07dd6ce..3bd49d914b22 100644
--- a/include/linux/font.h
+++ b/include/linux/font.h
@@ -11,10 +11,50 @@
 #ifndef _VIDEO_FONT_H
 #define _VIDEO_FONT_H
 
+#include <linux/math.h>
 #include <linux/types.h>
 
 struct console_font;
 
+/*
+ * Glyphs
+ */
+
+/**
+ * font_glyph_pitch - Calculates the number of bytes per scanline
+ * @width: The glyph width in bits per scanline
+ *
+ * A glyph's pitch is the number of bytes in a single scanline, rounded
+ * up to the next full byte. The parameter @width receives the number
+ * of visible bits per scanline. For example, if width is 14 bytes per
+ * scanline, the pitch is 2 bytes per scanline. If width is 8 bits per
+ * scanline, the pitch is 1 byte per scanline.
+ *
+ * Returns:
+ * The number of bytes in a single scanline of the glyph
+ */
+static inline unsigned int font_glyph_pitch(unsigned int width)
+{
+	return DIV_ROUND_UP(width, 8);
+}
+
+/**
+ * font_glyph_size - Calculates the number of bytes per glyph
+ * @width: The glyph width in bits per scanline
+ * @vpitch: The number of scanlines in the glyph
+ *
+ * The number of bytes in a glyph depends on the pitch and the number
+ * of scanlines. font_glyph_size automatically calculates the pitch
+ * from the given width. The parameter @vpitch gives the number of
+ * scanlines, which is usually the glyph's height in scanlines. Fonts
+ * coming from user space can sometimes have a different vertical pitch
+ * with empty scanlines between two adjacent glyphs.
+ */
+static inline unsigned int font_glyph_size(unsigned int width, unsigned int vpitch)
+{
+	return font_glyph_pitch(width) * vpitch;
+}
+
 /*
  * font_data_t and helpers
  */
diff --git a/lib/fonts/fonts.c b/lib/fonts/fonts.c
index 5938f542906b..f5d5333450a0 100644
--- a/lib/fonts/fonts.c
+++ b/lib/fonts/fonts.c
@@ -26,7 +26,7 @@
 
 #include "font.h"
 
-#define console_font_pitch(font) DIV_ROUND_UP((font)->width, 8)
+#define console_font_pitch(font) font_glyph_pitch((font)->width)
 
 /*
  * Helpers for font_data_t
-- 
2.53.0

[PATCH 04/10] lib/fonts: Clean up Makefile

[Thomas Zimmermann]

Simplify the Makefile. Drop font-obj-y and sort the fonts by dictionary
order. Done in preparation for supporting optional font rotation.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 lib/fonts/Makefile | 35 +++++++++++++++++------------------
 1 file changed, 17 insertions(+), 18 deletions(-)

diff --git a/lib/fonts/Makefile b/lib/fonts/Makefile
index 30a85a4292fa..3268d344c0a1 100644
--- a/lib/fonts/Makefile
+++ b/lib/fonts/Makefile
@@ -1,23 +1,22 @@
 # SPDX-License-Identifier: GPL-2.0
 # Font handling
 
-font-objs := fonts.o
+font-y := fonts.o
 
-font-objs-$(CONFIG_FONT_SUN8x16)   += font_sun8x16.o
-font-objs-$(CONFIG_FONT_SUN12x22)  += font_sun12x22.o
-font-objs-$(CONFIG_FONT_8x8)       += font_8x8.o
-font-objs-$(CONFIG_FONT_8x16)      += font_8x16.o
-font-objs-$(CONFIG_FONT_6x11)      += font_6x11.o
-font-objs-$(CONFIG_FONT_7x14)      += font_7x14.o
-font-objs-$(CONFIG_FONT_10x18)     += font_10x18.o
-font-objs-$(CONFIG_FONT_PEARL_8x8) += font_pearl_8x8.o
-font-objs-$(CONFIG_FONT_ACORN_8x8) += font_acorn_8x8.o
-font-objs-$(CONFIG_FONT_MINI_4x6)  += font_mini_4x6.o
-font-objs-$(CONFIG_FONT_6x10)      += font_6x10.o
-font-objs-$(CONFIG_FONT_TER10x18)  += font_ter10x18.o
-font-objs-$(CONFIG_FONT_TER16x32)  += font_ter16x32.o
-font-objs-$(CONFIG_FONT_6x8)       += font_6x8.o
+# Built-in fonts
+font-$(CONFIG_FONT_10x18)     += font_10x18.o
+font-$(CONFIG_FONT_6x10)      += font_6x10.o
+font-$(CONFIG_FONT_6x11)      += font_6x11.o
+font-$(CONFIG_FONT_6x8)       += font_6x8.o
+font-$(CONFIG_FONT_7x14)      += font_7x14.o
+font-$(CONFIG_FONT_8x16)      += font_8x16.o
+font-$(CONFIG_FONT_8x8)       += font_8x8.o
+font-$(CONFIG_FONT_ACORN_8x8) += font_acorn_8x8.o
+font-$(CONFIG_FONT_MINI_4x6)  += font_mini_4x6.o
+font-$(CONFIG_FONT_PEARL_8x8) += font_pearl_8x8.o
+font-$(CONFIG_FONT_SUN12x22)  += font_sun12x22.o
+font-$(CONFIG_FONT_SUN8x16)   += font_sun8x16.o
+font-$(CONFIG_FONT_TER10x18)  += font_ter10x18.o
+font-$(CONFIG_FONT_TER16x32)  += font_ter16x32.o
 
-font-objs += $(font-objs-y)
-
-obj-$(CONFIG_FONT_SUPPORT)         += font.o
+obj-$(CONFIG_FONT_SUPPORT) += font.o
-- 
2.53.0

[PATCH 05/10] lib/fonts: Implement glyph rotation

[Thomas Zimmermann]

Move the glphy rotation helpers from fbcon to the font library. Wrap them
behind clean interfaces. Also clear the output memory to zero. Previously,
the implementation relied on the caller to do that.

Go through the fbcon code and callers of the glyph-rotation helpers. In
addition to the font rotation, there's also the cursor code, which uses
the rotation helpers.

The font-rotation relied on a single memset to zero for the whole font.
This is now multiple memsets on each glyph. This will be sorted out when
the font library also implements font rotation.

Building glyph rotation in the font library still depends on
CONFIG_FRAMEBUFFER_CONSOLE_ROTATION=y. If we get more users of the code,
we can still add a dedicated Kconfig symbol to the font library.

No changes have been made to the actual implementation of the rotate_*()
and pattern_*() functions. These will be refactored as separate changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/video/fbdev/core/fbcon_ccw.c    |   4 +-
 drivers/video/fbdev/core/fbcon_cw.c     |   4 +-
 drivers/video/fbdev/core/fbcon_rotate.c |  12 +-
 drivers/video/fbdev/core/fbcon_rotate.h |  71 -----------
 include/linux/font.h                    |   8 ++
 lib/fonts/Makefile                      |   1 +
 lib/fonts/font_rotate.c                 | 150 ++++++++++++++++++++++++
 7 files changed, 167 insertions(+), 83 deletions(-)
 create mode 100644 lib/fonts/font_rotate.c

diff --git a/drivers/video/fbdev/core/fbcon_ccw.c b/drivers/video/fbdev/core/fbcon_ccw.c
index 96ef449ee6ac..72453a2aaca8 100644
--- a/drivers/video/fbdev/core/fbcon_ccw.c
+++ b/drivers/video/fbdev/core/fbcon_ccw.c
@@ -12,6 +12,7 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/fb.h>
+#include <linux/font.h>
 #include <linux/vt_kern.h>
 #include <linux/console.h>
 #include <asm/types.h>
@@ -344,8 +345,7 @@ static void ccw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 		size = cur_height * width;
 		while (size--)
 			tmp[i++] = 0xff;
-		memset(mask, 0, w * vc->vc_font.width);
-		rotate_ccw(tmp, mask, vc->vc_font.width, vc->vc_font.height);
+		font_glyph_rotate_270(tmp, vc->vc_font.width, vc->vc_font.height, mask);
 		kfree(tmp);
 	}
 
diff --git a/drivers/video/fbdev/core/fbcon_cw.c b/drivers/video/fbdev/core/fbcon_cw.c
index ea712654edae..5690fc1d7854 100644
--- a/drivers/video/fbdev/core/fbcon_cw.c
+++ b/drivers/video/fbdev/core/fbcon_cw.c
@@ -12,6 +12,7 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/fb.h>
+#include <linux/font.h>
 #include <linux/vt_kern.h>
 #include <linux/console.h>
 #include <asm/types.h>
@@ -327,8 +328,7 @@ static void cw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 		size = cur_height * width;
 		while (size--)
 			tmp[i++] = 0xff;
-		memset(mask, 0, w * vc->vc_font.width);
-		rotate_cw(tmp, mask, vc->vc_font.width, vc->vc_font.height);
+		font_glyph_rotate_90(tmp, vc->vc_font.width, vc->vc_font.height, mask);
 		kfree(tmp);
 	}
 
diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index 18575c5182db..588dc9d6758a 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -12,6 +12,7 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/fb.h>
+#include <linux/font.h>
 #include <linux/vt_kern.h>
 #include <linux/console.h>
 #include <asm/types.h>
@@ -60,30 +61,25 @@ int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 	}
 
 	dst = par->fontbuffer;
-	memset(dst, 0, par->fd_size);
 
 	switch (par->rotate) {
 	case FB_ROTATE_UD:
 		for (i = len; i--; ) {
-			rotate_ud(src, dst, vc->vc_font.width,
-				  vc->vc_font.height);
-
+			font_glyph_rotate_180(src, vc->vc_font.width, vc->vc_font.height, dst);
 			src += s_cellsize;
 			dst += d_cellsize;
 		}
 		break;
 	case FB_ROTATE_CW:
 		for (i = len; i--; ) {
-			rotate_cw(src, dst, vc->vc_font.width,
-				  vc->vc_font.height);
+			font_glyph_rotate_90(src, vc->vc_font.width, vc->vc_font.height, dst);
 			src += s_cellsize;
 			dst += d_cellsize;
 		}
 		break;
 	case FB_ROTATE_CCW:
 		for (i = len; i--; ) {
-			rotate_ccw(src, dst, vc->vc_font.width,
-				   vc->vc_font.height);
+			font_glyph_rotate_270(src, vc->vc_font.width, vc->vc_font.height, dst);
 			src += s_cellsize;
 			dst += d_cellsize;
 		}
diff --git a/drivers/video/fbdev/core/fbcon_rotate.h b/drivers/video/fbdev/core/fbcon_rotate.h
index 8cb019e8a9c0..725bcae2df61 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.h
+++ b/drivers/video/fbdev/core/fbcon_rotate.h
@@ -19,77 +19,6 @@
         (fb_scrollmode(s) == SCROLL_REDRAW || fb_scrollmode(s) == SCROLL_MOVE || !(i)->fix.xpanstep) ? \
         (i)->var.xres : (i)->var.xres_virtual; })
 
-
-static inline int pattern_test_bit(u32 x, u32 y, u32 pitch, const char *pat)
-{
-	u32 tmp = (y * pitch) + x, index = tmp / 8,  bit = tmp % 8;
-
-	pat +=index;
-	return (*pat) & (0x80 >> bit);
-}
-
-static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat)
-{
-	u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8;
-
-	pat += index;
-
-	(*pat) |= 0x80 >> bit;
-}
-
-static inline void rotate_ud(const char *in, char *out, u32 width, u32 height)
-{
-	int i, j;
-	int shift = (8 - (width % 8)) & 7;
-
-	width = (width + 7) & ~7;
-
-	for (i = 0; i < height; i++) {
-		for (j = 0; j < width - shift; j++) {
-			if (pattern_test_bit(j, i, width, in))
-				pattern_set_bit(width - (1 + j + shift),
-						height - (1 + i),
-						width, out);
-		}
-
-	}
-}
-
-static inline void rotate_cw(const char *in, char *out, u32 width, u32 height)
-{
-	int i, j, h = height, w = width;
-	int shift = (8 - (height % 8)) & 7;
-
-	width = (width + 7) & ~7;
-	height = (height + 7) & ~7;
-
-	for (i = 0; i < h; i++) {
-		for (j = 0; j < w; j++) {
-			if (pattern_test_bit(j, i, width, in))
-				pattern_set_bit(height - 1 - i - shift, j,
-						height, out);
-
-		}
-	}
-}
-
-static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height)
-{
-	int i, j, h = height, w = width;
-	int shift = (8 - (width % 8)) & 7;
-
-	width = (width + 7) & ~7;
-	height = (height + 7) & ~7;
-
-	for (i = 0; i < h; i++) {
-		for (j = 0; j < w; j++) {
-			if (pattern_test_bit(j, i, width, in))
-				pattern_set_bit(i, width - 1 - j - shift,
-						height, out);
-		}
-	}
-}
-
 int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc);
 
 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_ROTATION)
diff --git a/include/linux/font.h b/include/linux/font.h
index 3bd49d914b22..0a240dd70422 100644
--- a/include/linux/font.h
+++ b/include/linux/font.h
@@ -104,6 +104,14 @@ unsigned int font_data_size(font_data_t *fd);
 bool font_data_is_equal(font_data_t *lhs, font_data_t *rhs);
 int font_data_export(font_data_t *fd, struct console_font *font, unsigned int vpitch);
 
+/* font_rotate.c */
+void font_glyph_rotate_90(const unsigned char *glyph, unsigned int width, unsigned int height,
+			  unsigned char *out);
+void font_glyph_rotate_180(const unsigned char *glyph, unsigned int width, unsigned int height,
+			   unsigned char *out);
+void font_glyph_rotate_270(const unsigned char *glyph, unsigned int width, unsigned int height,
+			   unsigned char *out);
+
 /*
  * Font description
  */
diff --git a/lib/fonts/Makefile b/lib/fonts/Makefile
index 3268d344c0a1..32ece0e265c8 100644
--- a/lib/fonts/Makefile
+++ b/lib/fonts/Makefile
@@ -2,6 +2,7 @@
 # Font handling
 
 font-y := fonts.o
+font-$(CONFIG_FRAMEBUFFER_CONSOLE_ROTATION) += font_rotate.o
 
 # Built-in fonts
 font-$(CONFIG_FONT_10x18)     += font_10x18.o
diff --git a/lib/fonts/font_rotate.c b/lib/fonts/font_rotate.c
new file mode 100644
index 000000000000..3e0a19c889f3
--- /dev/null
+++ b/lib/fonts/font_rotate.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Font rotation
+ *
+ *    Copyright (C) 2005 Antonino Daplas <adaplas @pol.net>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/export.h>
+#include <linux/math.h>
+#include <linux/string.h>
+
+#include "font.h"
+
+static inline int pattern_test_bit(u32 x, u32 y, u32 pitch, const char *pat)
+{
+	u32 tmp = (y * pitch) + x, index = tmp / 8,  bit = tmp % 8;
+
+	pat += index;
+	return (*pat) & (0x80 >> bit);
+}
+
+static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat)
+{
+	u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8;
+
+	pat += index;
+
+	(*pat) |= 0x80 >> bit;
+}
+
+static inline void rotate_cw(const char *in, char *out, u32 width, u32 height)
+{
+	int i, j, h = height, w = width;
+	int shift = (8 - (height % 8)) & 7;
+
+	width = (width + 7) & ~7;
+	height = (height + 7) & ~7;
+
+	for (i = 0; i < h; i++) {
+		for (j = 0; j < w; j++) {
+			if (pattern_test_bit(j, i, width, in))
+				pattern_set_bit(height - 1 - i - shift, j,
+						height, out);
+		}
+	}
+}
+
+/**
+ * font_glyph_rotate_90 - Rotate a glyph pattern by 90° in clockwise direction
+ * @glyph: The glyph to rotate
+ * @width: The glyph width in bits per scanline
+ * @height: The number of scanlines in the glyph
+ * @out: The rotated glyph bitmap
+ *
+ * The parameters @width and @height refer to the input glyph given in @glyph.
+ * The caller has to provide the output buffer @out of sufficient size to hold
+ * the rotated glyph. Rotating by 90° flips the width and height for the output
+ * glyph. Depending on the glyph pitch, the size of the output glyph can be
+ * different then the size of the input. Caller shave to take this into account
+ * when allocating the output memory.
+ */
+void font_glyph_rotate_90(const unsigned char *glyph, unsigned int width, unsigned int height,
+			  unsigned char *out)
+{
+	memset(out, 0, font_glyph_size(height, width)); /* flip width/height */
+
+	rotate_cw(glyph, out, width, height);
+}
+EXPORT_SYMBOL_GPL(font_glyph_rotate_90);
+
+static inline void rotate_ud(const char *in, char *out, u32 width, u32 height)
+{
+	int i, j;
+	int shift = (8 - (width % 8)) & 7;
+
+	width = (width + 7) & ~7;
+
+	for (i = 0; i < height; i++) {
+		for (j = 0; j < width - shift; j++) {
+			if (pattern_test_bit(j, i, width, in))
+				pattern_set_bit(width - (1 + j + shift),
+						height - (1 + i),
+						width, out);
+		}
+	}
+}
+
+/**
+ * font_glyph_rotate_180 - Rotate a glyph pattern by 180°
+ * @glyph: The glyph to rotate
+ * @width: The glyph width in bits per scanline
+ * @height: The number of scanlines in the glyph
+ * @out: The rotated glyph bitmap
+ *
+ * The parameters @width and @height refer to the input glyph given in @glyph.
+ * The caller has to provide the output buffer @out of sufficient size to hold
+ * the rotated glyph.
+ */
+void font_glyph_rotate_180(const unsigned char *glyph, unsigned int width, unsigned int height,
+			   unsigned char *out)
+{
+	memset(out, 0, font_glyph_size(width, height));
+
+	rotate_ud(glyph, out, width, height);
+}
+EXPORT_SYMBOL_GPL(font_glyph_rotate_180);
+
+static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height)
+{
+	int i, j, h = height, w = width;
+	int shift = (8 - (width % 8)) & 7;
+
+	width = (width + 7) & ~7;
+	height = (height + 7) & ~7;
+
+	for (i = 0; i < h; i++) {
+		for (j = 0; j < w; j++) {
+			if (pattern_test_bit(j, i, width, in))
+				pattern_set_bit(i, width - 1 - j - shift,
+						height, out);
+		}
+	}
+}
+
+/**
+ * font_glyph_rotate_270 - Rotate a glyph pattern by 270° in clockwise direction
+ * @glyph: The glyph to rotate
+ * @width: The glyph width in bits per scanline
+ * @height: The number of scanlines in the glyph
+ * @out: The rotated glyph bitmap
+ *
+ * The parameters @width and @height refer to the input glyph given in @glyph.
+ * The caller has to provide the output buffer @out of sufficient size to hold
+ * the rotated glyph. Rotating by 270° flips the width and height for the output
+ * glyph. Depending on the glyph pitch, the size of the output glyph can be
+ * different then the size of the input. Caller shave to take this into account
+ * when allocating the output memory.
+ */
+void font_glyph_rotate_270(const unsigned char *glyph, unsigned int width, unsigned int height,
+			   unsigned char *out)
+{
+	memset(out, 0, font_glyph_size(height, width)); /* flip width/height */
+
+	rotate_ccw(glyph, out, width, height);
+}
+EXPORT_SYMBOL_GPL(font_glyph_rotate_270);
-- 
2.53.0

[PATCH 06/10] lib/fonts: Refactor glyph-pattern helpers

[Thomas Zimmermann]

Change the signatures of the pattern helpers to align them with other
font-glyph helpers: use the font_glyph_ prefix and pass the glyph
buffer first.

Calculating the position of the involved bit is somewhat obfuscated
in the original implementation. Move it into the new helper
__font_glphy_pos() and use the result as array index and bit position.

Note that these bit helpers use a bit pitch, while other code uses a
byte pitch. This is intentional an required here.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 lib/fonts/font_rotate.c | 45 ++++++++++++++++++++++++-----------------
 1 file changed, 27 insertions(+), 18 deletions(-)

diff --git a/lib/fonts/font_rotate.c b/lib/fonts/font_rotate.c
index 3e0a19c889f3..cfaf5b98f49a 100644
--- a/lib/fonts/font_rotate.c
+++ b/lib/fonts/font_rotate.c
@@ -15,21 +15,33 @@
 
 #include "font.h"
 
-static inline int pattern_test_bit(u32 x, u32 y, u32 pitch, const char *pat)
+static unsigned int __font_glyph_pos(unsigned int x, unsigned int y, unsigned int bit_pitch,
+				     unsigned int *bit)
 {
-	u32 tmp = (y * pitch) + x, index = tmp / 8,  bit = tmp % 8;
+	unsigned int off = y * bit_pitch + x;
+	unsigned int bit_shift = off % 8;
 
-	pat += index;
-	return (*pat) & (0x80 >> bit);
+	*bit = 0x80 >> bit_shift; /* MSB has position 0, LSB has position 7 */
+
+	return off / 8;
 }
 
-static inline void pattern_set_bit(u32 x, u32 y, u32 pitch, char *pat)
+static bool font_glyph_test_bit(const unsigned char *glyph, unsigned int x, unsigned int y,
+				unsigned int bit_pitch)
 {
-	u32 tmp = (y * pitch) + x, index = tmp / 8, bit = tmp % 8;
+	unsigned int bit;
+	unsigned int i = __font_glyph_pos(x, y, bit_pitch, &bit);
+
+	return glyph[i] & bit;
+}
 
-	pat += index;
+static void font_glyph_set_bit(unsigned char *glyph, unsigned int x, unsigned int y,
+			       unsigned int bit_pitch)
+{
+	unsigned int bit;
+	unsigned int i = __font_glyph_pos(x, y, bit_pitch, &bit);
 
-	(*pat) |= 0x80 >> bit;
+	glyph[i] |= bit;
 }
 
 static inline void rotate_cw(const char *in, char *out, u32 width, u32 height)
@@ -42,9 +54,8 @@ static inline void rotate_cw(const char *in, char *out, u32 width, u32 height)
 
 	for (i = 0; i < h; i++) {
 		for (j = 0; j < w; j++) {
-			if (pattern_test_bit(j, i, width, in))
-				pattern_set_bit(height - 1 - i - shift, j,
-						height, out);
+			if (font_glyph_test_bit(in, j, i, width))
+				font_glyph_set_bit(out, height - 1 - i - shift, j, height);
 		}
 	}
 }
@@ -81,10 +92,9 @@ static inline void rotate_ud(const char *in, char *out, u32 width, u32 height)
 
 	for (i = 0; i < height; i++) {
 		for (j = 0; j < width - shift; j++) {
-			if (pattern_test_bit(j, i, width, in))
-				pattern_set_bit(width - (1 + j + shift),
-						height - (1 + i),
-						width, out);
+			if (font_glyph_test_bit(in, j, i, width))
+				font_glyph_set_bit(out, width - (1 + j + shift),
+						   height - (1 + i), width);
 		}
 	}
 }
@@ -119,9 +129,8 @@ static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height)
 
 	for (i = 0; i < h; i++) {
 		for (j = 0; j < w; j++) {
-			if (pattern_test_bit(j, i, width, in))
-				pattern_set_bit(i, width - 1 - j - shift,
-						height, out);
+			if (font_glyph_test_bit(in, j, i, width))
+				font_glyph_set_bit(out, i, width - 1 - j - shift, height);
 		}
 	}
 }
-- 
2.53.0

[PATCH 07/10] lib/fonts: Refactor glyph-rotation helpers

[Thomas Zimmermann]

Change the signatures of the glyph-rotation helpers to match their
public interfaces. Drop the inline qualifier.

Rename several variables to better match their meaning. Especially
rename variables to bit_pitch (or a variant thereof) if they store
a pitch value in bits per scanline. The original code is fairly
confusing about this. Move the calculation of the bit pitch into the
new helper font_glyph_bit_pitch().

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 lib/fonts/font_rotate.c | 85 ++++++++++++++++++++++++-----------------
 1 file changed, 49 insertions(+), 36 deletions(-)

diff --git a/lib/fonts/font_rotate.c b/lib/fonts/font_rotate.c
index cfaf5b98f49a..f1e441a931ab 100644
--- a/lib/fonts/font_rotate.c
+++ b/lib/fonts/font_rotate.c
@@ -15,6 +15,12 @@
 
 #include "font.h"
 
+/* number of bits per line */
+static unsigned int font_glyph_bit_pitch(unsigned int width)
+{
+	return round_up(width, 8);
+}
+
 static unsigned int __font_glyph_pos(unsigned int x, unsigned int y, unsigned int bit_pitch,
 				     unsigned int *bit)
 {
@@ -44,18 +50,21 @@ static void font_glyph_set_bit(unsigned char *glyph, unsigned int x, unsigned in
 	glyph[i] |= bit;
 }
 
-static inline void rotate_cw(const char *in, char *out, u32 width, u32 height)
+static void __font_glyph_rotate_90(const unsigned char *glyph,
+				   unsigned int width, unsigned int height,
+				   unsigned char *out)
 {
-	int i, j, h = height, w = width;
-	int shift = (8 - (height % 8)) & 7;
-
-	width = (width + 7) & ~7;
-	height = (height + 7) & ~7;
-
-	for (i = 0; i < h; i++) {
-		for (j = 0; j < w; j++) {
-			if (font_glyph_test_bit(in, j, i, width))
-				font_glyph_set_bit(out, height - 1 - i - shift, j, height);
+	unsigned int x, y;
+	unsigned int shift = (8 - (height % 8)) & 7;
+	unsigned int bit_pitch = font_glyph_bit_pitch(width);
+	unsigned int out_bit_pitch = font_glyph_bit_pitch(height);
+
+	for (y = 0; y < height; y++) {
+		for (x = 0; x < width; x++) {
+			if (font_glyph_test_bit(glyph, x, y, bit_pitch)) {
+				font_glyph_set_bit(out, out_bit_pitch - 1 - y - shift, x,
+						   out_bit_pitch);
+			}
 		}
 	}
 }
@@ -79,22 +88,24 @@ void font_glyph_rotate_90(const unsigned char *glyph, unsigned int width, unsign
 {
 	memset(out, 0, font_glyph_size(height, width)); /* flip width/height */
 
-	rotate_cw(glyph, out, width, height);
+	__font_glyph_rotate_90(glyph, width, height, out);
 }
 EXPORT_SYMBOL_GPL(font_glyph_rotate_90);
 
-static inline void rotate_ud(const char *in, char *out, u32 width, u32 height)
+static void __font_glyph_rotate_180(const unsigned char *glyph,
+				    unsigned int width, unsigned int height,
+				    unsigned char *out)
 {
-	int i, j;
-	int shift = (8 - (width % 8)) & 7;
-
-	width = (width + 7) & ~7;
-
-	for (i = 0; i < height; i++) {
-		for (j = 0; j < width - shift; j++) {
-			if (font_glyph_test_bit(in, j, i, width))
-				font_glyph_set_bit(out, width - (1 + j + shift),
-						   height - (1 + i), width);
+	unsigned int x, y;
+	unsigned int shift = (8 - (width % 8)) & 7;
+	unsigned int bit_pitch = font_glyph_bit_pitch(width);
+
+	for (y = 0; y < height; y++) {
+		for (x = 0; x < width; x++) {
+			if (font_glyph_test_bit(glyph, x, y, bit_pitch)) {
+				font_glyph_set_bit(out, width - (1 + x + shift), height - (1 + y),
+						   bit_pitch);
+			}
 		}
 	}
 }
@@ -115,22 +126,24 @@ void font_glyph_rotate_180(const unsigned char *glyph, unsigned int width, unsig
 {
 	memset(out, 0, font_glyph_size(width, height));
 
-	rotate_ud(glyph, out, width, height);
+	__font_glyph_rotate_180(glyph, width, height, out);
 }
 EXPORT_SYMBOL_GPL(font_glyph_rotate_180);
 
-static inline void rotate_ccw(const char *in, char *out, u32 width, u32 height)
+static void __font_glyph_rotate_270(const unsigned char *glyph,
+				    unsigned int width, unsigned int height,
+				    unsigned char *out)
 {
-	int i, j, h = height, w = width;
-	int shift = (8 - (width % 8)) & 7;
-
-	width = (width + 7) & ~7;
-	height = (height + 7) & ~7;
-
-	for (i = 0; i < h; i++) {
-		for (j = 0; j < w; j++) {
-			if (font_glyph_test_bit(in, j, i, width))
-				font_glyph_set_bit(out, i, width - 1 - j - shift, height);
+	unsigned int x, y;
+	unsigned int shift = (8 - (width % 8)) & 7;
+	unsigned int bit_pitch = font_glyph_bit_pitch(width);
+	unsigned int out_bit_pitch = font_glyph_bit_pitch(height);
+
+	for (y = 0; y < height; y++) {
+		for (x = 0; x < width; x++) {
+			if (font_glyph_test_bit(glyph, x, y, bit_pitch))
+				font_glyph_set_bit(out, y, bit_pitch - 1 - x - shift,
+						   out_bit_pitch);
 		}
 	}
 }
@@ -154,6 +167,6 @@ void font_glyph_rotate_270(const unsigned char *glyph, unsigned int width, unsig
 {
 	memset(out, 0, font_glyph_size(height, width)); /* flip width/height */
 
-	rotate_ccw(glyph, out, width, height);
+	__font_glyph_rotate_270(glyph, width, height, out);
 }
 EXPORT_SYMBOL_GPL(font_glyph_rotate_270);
-- 
2.53.0

[PATCH 08/10] lib/fonts: Implement font rotation

[Thomas Zimmermann]

Move the core of fbcon's font-rotation code to the font library as
the new helper font_data_rotate(). The code can rotate in steps of
90°. For completeness, it also copies the glyph data for multiples
of 360°.

Bring back the memset optimization. A memset to 0 again clears the
whole glyph output buffer. Then use the internal rotation helpers on
the cleared output. Fbcon's original implementation worked like this,
but lost it during refactoring.

Replace fbcon's font-rotation code with the new implementations.
All that's left to do for fbcon is to maintain its internal fbcon
state.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/video/fbdev/core/fbcon.h        |   2 +-
 drivers/video/fbdev/core/fbcon_rotate.c |  78 +++++-------------
 include/linux/font.h                    |   3 +
 lib/fonts/font_rotate.c                 | 103 ++++++++++++++++++++++++
 4 files changed, 126 insertions(+), 60 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcon.h b/drivers/video/fbdev/core/fbcon.h
index 1e3c1ef84762..1793f34a6c84 100644
--- a/drivers/video/fbdev/core/fbcon.h
+++ b/drivers/video/fbdev/core/fbcon.h
@@ -86,7 +86,7 @@ struct fbcon_par {
 	const u8    *fontdata;
 	u8    *cursor_src;
 	u32    cursor_size;
-	u32    fd_size;
+	size_t fd_size;
 
 	const struct fbcon_bitops *bitops;
 };
diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index 588dc9d6758a..74206f5a6e98 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -8,84 +8,44 @@
  *  more details.
  */
 
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/string.h>
+#include <linux/errno.h>
 #include <linux/fb.h>
 #include <linux/font.h>
-#include <linux/vt_kern.h>
-#include <linux/console.h>
-#include <asm/types.h>
+
 #include "fbcon.h"
 #include "fbcon_rotate.h"
 
 int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 {
 	struct fbcon_par *par = info->fbcon_par;
-	int len, err = 0;
-	int s_cellsize, d_cellsize, i;
-	const u8 *src;
-	u8 *dst;
+	unsigned char *fontbuffer;
+	int ret;
 
 	if (vc->vc_font.data == par->fontdata &&
 	    par->p->con_rotate == par->cur_rotate)
-		goto finished;
+		return 0;
 
-	src = par->fontdata = vc->vc_font.data;
+	par->fontdata = vc->vc_font.data;
 	par->cur_rotate = par->p->con_rotate;
-	len = vc->vc_font.charcount;
-	s_cellsize = font_glyph_size(vc->vc_font.width, vc->vc_font.height);
-	d_cellsize = s_cellsize;
-
-	if (par->rotate == FB_ROTATE_CW ||
-	    par->rotate == FB_ROTATE_CCW)
-		d_cellsize = font_glyph_size(vc->vc_font.height, vc->vc_font.width);
 
 	if (info->fbops->fb_sync)
 		info->fbops->fb_sync(info);
 
-	if (par->fd_size < d_cellsize * len) {
-		kfree(par->fontbuffer);
-		par->fontbuffer = NULL;
-		par->fd_size = 0;
-
-		dst = kmalloc_array(len, d_cellsize, GFP_KERNEL);
-
-		if (dst == NULL) {
-			err = -ENOMEM;
-			goto finished;
-		}
-
-		par->fd_size = d_cellsize * len;
-		par->fontbuffer = dst;
+	fontbuffer = font_data_rotate(par->p->fontdata, vc->vc_font.width,
+				      vc->vc_font.height, vc->vc_font.charcount,
+				      par->rotate, par->fontbuffer, &par->fd_size);
+	if (IS_ERR(fontbuffer)) {
+		ret = PTR_ERR(fontbuffer);
+		goto err_kfree;
 	}
 
-	dst = par->fontbuffer;
+	par->fontbuffer = fontbuffer;
 
-	switch (par->rotate) {
-	case FB_ROTATE_UD:
-		for (i = len; i--; ) {
-			font_glyph_rotate_180(src, vc->vc_font.width, vc->vc_font.height, dst);
-			src += s_cellsize;
-			dst += d_cellsize;
-		}
-		break;
-	case FB_ROTATE_CW:
-		for (i = len; i--; ) {
-			font_glyph_rotate_90(src, vc->vc_font.width, vc->vc_font.height, dst);
-			src += s_cellsize;
-			dst += d_cellsize;
-		}
-		break;
-	case FB_ROTATE_CCW:
-		for (i = len; i--; ) {
-			font_glyph_rotate_270(src, vc->vc_font.width, vc->vc_font.height, dst);
-			src += s_cellsize;
-			dst += d_cellsize;
-		}
-		break;
-	}
+	return 0;
+
+err_kfree:
+	kfree(par->fontbuffer);
+	par->fontbuffer = NULL; /* clear here to avoid output */
 
-finished:
-	return err;
+	return ret;
 }
diff --git a/include/linux/font.h b/include/linux/font.h
index 0a240dd70422..6845f02d739a 100644
--- a/include/linux/font.h
+++ b/include/linux/font.h
@@ -111,6 +111,9 @@ void font_glyph_rotate_180(const unsigned char *glyph, unsigned int width, unsig
 			   unsigned char *out);
 void font_glyph_rotate_270(const unsigned char *glyph, unsigned int width, unsigned int height,
 			   unsigned char *out);
+unsigned char *font_data_rotate(font_data_t *fd, unsigned int width, unsigned int height,
+				unsigned int charcount, unsigned int steps,
+				unsigned char *buf, size_t *bufsize);
 
 /*
  * Font description
diff --git a/lib/fonts/font_rotate.c b/lib/fonts/font_rotate.c
index f1e441a931ab..d8c8973310c2 100644
--- a/lib/fonts/font_rotate.c
+++ b/lib/fonts/font_rotate.c
@@ -9,8 +9,11 @@
  * more details.
  */
 
+#include <linux/errno.h>
 #include <linux/export.h>
 #include <linux/math.h>
+#include <linux/overflow.h>
+#include <linux/slab.h>
 #include <linux/string.h>
 
 #include "font.h"
@@ -170,3 +173,103 @@ void font_glyph_rotate_270(const unsigned char *glyph, unsigned int width, unsig
 	__font_glyph_rotate_270(glyph, width, height, out);
 }
 EXPORT_SYMBOL_GPL(font_glyph_rotate_270);
+
+/**
+ * font_data_rotate - Rotate font data by multiples of 90°
+ * @fd: The font data to rotate
+ * @width: The glyph width in bits per scanline
+ * @height: The number of scanlines in the glyph
+ * @charcount: The number of glyphs in the font
+ * @steps: Number of rotation steps of 90°
+ * @buf: Preallocated output buffer; can be NULL
+ * @bufsize: The size of @buf in bytes; can be NULL
+ *
+ * The parameters @width and @height refer to the visible number of pixels
+ * and scanlines in a single glyph. The number of glyphs is given in @charcount.
+ * Rotation happens in steps of 90°. The @steps parameter can have any value,
+ * but only 0 to 3 produce distinct results. With 4 or higher, a full rotation
+ * has been performed. You can pass any value for @steps and the helper will
+ * perform the appropriate rotation. Note that the returned buffer is not
+ * compatible with font_data_t. It only contains glphy data in the same format
+ * as returned by font_data_buf(). Callers are responsible to free the returned
+ * buffer with kfree(). Font rotation typically happens when displays get
+ * re-oriented. To avoid unnecessary re-allocation of the memory buffer, the
+ * caller can pass in an earlier result buffer in @buf for reuse. The buffer
+ * size of given and returned in @bufsize. The allocation semantics are compatible
+ * with krealloc().
+ *
+ * Returns:
+ * A buffer with rotated glyphs on success, or an error pointer otherwise
+ */
+unsigned char *font_data_rotate(font_data_t *fd, unsigned int width, unsigned int height,
+				unsigned int charcount, unsigned int steps,
+				unsigned char *buf, size_t *bufsize)
+{
+	const unsigned char *src = font_data_buf(fd);
+	unsigned int s_cellsize = font_glyph_size(width, height);
+	unsigned int d_cellsize, i;
+	unsigned char *dst;
+	size_t size;
+
+	steps %= 4;
+
+	switch (steps) {
+	case 0:
+	case 2:
+		d_cellsize = s_cellsize;
+		break;
+	case 1:
+	case 3:
+		d_cellsize = font_glyph_size(height, width); /* flip width/height */
+		break;
+	}
+
+	if (check_mul_overflow(charcount, d_cellsize, &size))
+		return ERR_PTR(-EINVAL);
+
+	if (!buf || !bufsize || size > *bufsize) {
+		dst = kmalloc_array(charcount, d_cellsize, GFP_KERNEL);
+		if (!dst)
+			return ERR_PTR(-ENOMEM);
+
+		kfree(buf);
+		buf = dst;
+		if (bufsize)
+			*bufsize = size;
+	} else {
+		dst = buf;
+	}
+
+	switch (steps) {
+	case 0:
+		memcpy(dst, src, size);
+		break;
+	case 1:
+		memset(dst, 0, size);
+		for (i = 0; i < charcount; ++i) {
+			__font_glyph_rotate_90(src, width, height, dst);
+			src += s_cellsize;
+			dst += d_cellsize;
+		}
+		break;
+	case 2:
+		memset(dst, 0, size);
+		for (i = 0; i < charcount; ++i) {
+			__font_glyph_rotate_180(src, width, height, dst);
+			src += s_cellsize;
+			dst += d_cellsize;
+		}
+		break;
+	case 3:
+		memset(dst, 0, size);
+		for (i = 0; i < charcount; ++i) {
+			__font_glyph_rotate_270(src, width, height, dst);
+			src += s_cellsize;
+			dst += d_cellsize;
+		}
+		break;
+	}
+
+	return buf;
+}
+EXPORT_SYMBOL_GPL(font_data_rotate);
-- 
2.53.0

[PATCH 09/10] fbcon: Fill cursor mask in helper function

[Thomas Zimmermann]

Fbcon creates a cursor shape on the fly from the user-configured
settings. The logic to create a glyph with the cursor's bitmap mask
is duplicated in four places. In the cases that involve console
rotation, the implementation further rotates the cursor glyph for
displaying.

Consolidate all cursor-mask creation in a single helper. Update the
callers accordingly. For console rotation, use the glyph helpers to
rotate the created cursor glyph to the correct orientation.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/video/fbdev/core/bitblit.c   | 35 ++-----------------
 drivers/video/fbdev/core/fbcon.c     | 40 ++++++++++++++++++++++
 drivers/video/fbdev/core/fbcon.h     |  2 ++
 drivers/video/fbdev/core/fbcon_ccw.c | 51 ++++++----------------------
 drivers/video/fbdev/core/fbcon_cw.c  | 51 ++++++----------------------
 drivers/video/fbdev/core/fbcon_ud.c  | 50 +++++++--------------------
 6 files changed, 78 insertions(+), 151 deletions(-)

diff --git a/drivers/video/fbdev/core/bitblit.c b/drivers/video/fbdev/core/bitblit.c
index 7478accea8ec..65681dcc5930 100644
--- a/drivers/video/fbdev/core/bitblit.c
+++ b/drivers/video/fbdev/core/bitblit.c
@@ -329,46 +329,17 @@ static void bit_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	    vc->vc_cursor_type != par->p->cursor_shape ||
 	    par->cursor_state.mask == NULL ||
 	    par->cursor_reset) {
-		char *mask = kmalloc_array(w, vc->vc_font.height, GFP_ATOMIC);
-		int cur_height, size, i = 0;
-		u8 msk = 0xff;
+		unsigned char *mask = kmalloc_array(vc->vc_font.height, w, GFP_ATOMIC);
 
 		if (!mask)
 			return;
+		fbcon_fill_cursor_mask(par, vc, mask);
 
 		kfree(par->cursor_state.mask);
-		par->cursor_state.mask = mask;
+		par->cursor_state.mask = (const char *)mask;
 
 		par->p->cursor_shape = vc->vc_cursor_type;
 		cursor.set |= FB_CUR_SETSHAPE;
-
-		switch (CUR_SIZE(par->p->cursor_shape)) {
-		case CUR_NONE:
-			cur_height = 0;
-			break;
-		case CUR_UNDERLINE:
-			cur_height = (vc->vc_font.height < 10) ? 1 : 2;
-			break;
-		case CUR_LOWER_THIRD:
-			cur_height = vc->vc_font.height/3;
-			break;
-		case CUR_LOWER_HALF:
-			cur_height = vc->vc_font.height >> 1;
-			break;
-		case CUR_TWO_THIRDS:
-			cur_height = (vc->vc_font.height << 1)/3;
-			break;
-		case CUR_BLOCK:
-		default:
-			cur_height = vc->vc_font.height;
-			break;
-		}
-		size = (vc->vc_font.height - cur_height) * w;
-		while (size--)
-			mask[i++] = ~msk;
-		size = cur_height * w;
-		while (size--)
-			mask[i++] = msk;
 	}
 
 	par->cursor_state.enable = enable && !use_sw;
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 8641b0b3edc4..345d9aa193f0 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -446,6 +446,46 @@ static void fbcon_del_cursor_work(struct fb_info *info)
 	cancel_delayed_work_sync(&par->cursor_work);
 }
 
+void fbcon_fill_cursor_mask(struct fbcon_par *par, struct vc_data *vc, unsigned char *mask)
+{
+	static const unsigned char pattern = 0xff;
+	unsigned int pitch = vc_font_pitch(&vc->vc_font);
+	unsigned int cur_height, size;
+
+	switch (CUR_SIZE(vc->vc_cursor_type)) {
+	case CUR_NONE:
+		cur_height = 0;
+		break;
+	case CUR_UNDERLINE:
+		if (vc->vc_font.height < 10)
+			cur_height = 1;
+		else
+			cur_height = 2;
+		break;
+	case CUR_LOWER_THIRD:
+		cur_height = vc->vc_font.height / 3;
+		break;
+	case CUR_LOWER_HALF:
+		cur_height = vc->vc_font.height / 2;
+		break;
+	case CUR_TWO_THIRDS:
+		cur_height = (vc->vc_font.height * 2) / 3;
+		break;
+	case CUR_BLOCK:
+	default:
+		cur_height = vc->vc_font.height;
+		break;
+	}
+
+	size = (vc->vc_font.height - cur_height) * pitch;
+	while (size--)
+		*mask++ = (unsigned char)~pattern;
+
+	size = cur_height * pitch;
+	while (size--)
+		*mask++ = pattern;
+}
+
 #ifndef MODULE
 static int __init fb_console_setup(char *this_opt)
 {
diff --git a/drivers/video/fbdev/core/fbcon.h b/drivers/video/fbdev/core/fbcon.h
index 1793f34a6c84..bb0727b70631 100644
--- a/drivers/video/fbdev/core/fbcon.h
+++ b/drivers/video/fbdev/core/fbcon.h
@@ -192,6 +192,8 @@ extern void fbcon_set_tileops(struct vc_data *vc, struct fb_info *info);
 extern void fbcon_set_bitops_ur(struct fbcon_par *par);
 extern int  soft_cursor(struct fb_info *info, struct fb_cursor *cursor);
 
+void fbcon_fill_cursor_mask(struct fbcon_par *par, struct vc_data *vc, unsigned char *mask);
+
 #define FBCON_ATTRIBUTE_UNDERLINE 1
 #define FBCON_ATTRIBUTE_REVERSE   2
 #define FBCON_ATTRIBUTE_BOLD      4
diff --git a/drivers/video/fbdev/core/fbcon_ccw.c b/drivers/video/fbdev/core/fbcon_ccw.c
index 72453a2aaca8..723d9a33067f 100644
--- a/drivers/video/fbdev/core/fbcon_ccw.c
+++ b/drivers/video/fbdev/core/fbcon_ccw.c
@@ -296,57 +296,26 @@ static void ccw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	    vc->vc_cursor_type != par->p->cursor_shape ||
 	    par->cursor_state.mask == NULL ||
 	    par->cursor_reset) {
-		char *tmp, *mask = kmalloc_array(w, vc->vc_font.width,
-						 GFP_ATOMIC);
-		int cur_height, size, i = 0;
-		int width = font_glyph_pitch(vc->vc_font.width);
+		unsigned char *tmp, *mask;
 
-		if (!mask)
+		tmp = kmalloc_array(vc->vc_font.height, vc_font_pitch(&vc->vc_font), GFP_ATOMIC);
+		if (!tmp)
 			return;
+		fbcon_fill_cursor_mask(par, vc, tmp);
 
-		tmp = kmalloc_array(width, vc->vc_font.height, GFP_ATOMIC);
-
-		if (!tmp) {
-			kfree(mask);
+		mask = kmalloc_array(vc->vc_font.width, w, GFP_ATOMIC);
+		if (!mask) {
+			kfree(tmp);
 			return;
 		}
+		font_glyph_rotate_270(tmp, vc->vc_font.width, vc->vc_font.height, mask);
+		kfree(tmp);
 
 		kfree(par->cursor_state.mask);
-		par->cursor_state.mask = mask;
+		par->cursor_state.mask = (const char *)mask;
 
 		par->p->cursor_shape = vc->vc_cursor_type;
 		cursor.set |= FB_CUR_SETSHAPE;
-
-		switch (CUR_SIZE(par->p->cursor_shape)) {
-		case CUR_NONE:
-			cur_height = 0;
-			break;
-		case CUR_UNDERLINE:
-			cur_height = (vc->vc_font.height < 10) ? 1 : 2;
-			break;
-		case CUR_LOWER_THIRD:
-			cur_height = vc->vc_font.height/3;
-			break;
-		case CUR_LOWER_HALF:
-			cur_height = vc->vc_font.height >> 1;
-			break;
-		case CUR_TWO_THIRDS:
-			cur_height = (vc->vc_font.height << 1)/3;
-			break;
-		case CUR_BLOCK:
-		default:
-			cur_height = vc->vc_font.height;
-			break;
-		}
-
-		size = (vc->vc_font.height - cur_height) * width;
-		while (size--)
-			tmp[i++] = 0;
-		size = cur_height * width;
-		while (size--)
-			tmp[i++] = 0xff;
-		font_glyph_rotate_270(tmp, vc->vc_font.width, vc->vc_font.height, mask);
-		kfree(tmp);
 	}
 
 	par->cursor_state.enable = enable && !use_sw;
diff --git a/drivers/video/fbdev/core/fbcon_cw.c b/drivers/video/fbdev/core/fbcon_cw.c
index 5690fc1d7854..732d093d462f 100644
--- a/drivers/video/fbdev/core/fbcon_cw.c
+++ b/drivers/video/fbdev/core/fbcon_cw.c
@@ -279,57 +279,26 @@ static void cw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	    vc->vc_cursor_type != par->p->cursor_shape ||
 	    par->cursor_state.mask == NULL ||
 	    par->cursor_reset) {
-		char *tmp, *mask = kmalloc_array(w, vc->vc_font.width,
-						 GFP_ATOMIC);
-		int cur_height, size, i = 0;
-		int width = font_glyph_pitch(vc->vc_font.width);
+		unsigned char *tmp, *mask;
 
-		if (!mask)
+		tmp = kmalloc_array(vc->vc_font.height, vc_font_pitch(&vc->vc_font), GFP_ATOMIC);
+		if (!tmp)
 			return;
+		fbcon_fill_cursor_mask(par, vc, tmp);
 
-		tmp = kmalloc_array(width, vc->vc_font.height, GFP_ATOMIC);
-
-		if (!tmp) {
-			kfree(mask);
+		mask = kmalloc_array(vc->vc_font.width, w, GFP_ATOMIC);
+		if (!mask) {
+			kfree(tmp);
 			return;
 		}
+		font_glyph_rotate_90(tmp, vc->vc_font.width, vc->vc_font.height, mask);
+		kfree(tmp);
 
 		kfree(par->cursor_state.mask);
-		par->cursor_state.mask = mask;
+		par->cursor_state.mask = (const char *)mask;
 
 		par->p->cursor_shape = vc->vc_cursor_type;
 		cursor.set |= FB_CUR_SETSHAPE;
-
-		switch (CUR_SIZE(par->p->cursor_shape)) {
-		case CUR_NONE:
-			cur_height = 0;
-			break;
-		case CUR_UNDERLINE:
-			cur_height = (vc->vc_font.height < 10) ? 1 : 2;
-			break;
-		case CUR_LOWER_THIRD:
-			cur_height = vc->vc_font.height/3;
-			break;
-		case CUR_LOWER_HALF:
-			cur_height = vc->vc_font.height >> 1;
-			break;
-		case CUR_TWO_THIRDS:
-			cur_height = (vc->vc_font.height << 1)/3;
-			break;
-		case CUR_BLOCK:
-		default:
-			cur_height = vc->vc_font.height;
-			break;
-		}
-
-		size = (vc->vc_font.height - cur_height) * width;
-		while (size--)
-			tmp[i++] = 0;
-		size = cur_height * width;
-		while (size--)
-			tmp[i++] = 0xff;
-		font_glyph_rotate_90(tmp, vc->vc_font.width, vc->vc_font.height, mask);
-		kfree(tmp);
 	}
 
 	par->cursor_state.enable = enable && !use_sw;
diff --git a/drivers/video/fbdev/core/fbcon_ud.c b/drivers/video/fbdev/core/fbcon_ud.c
index f7cd89c42b01..a1981fa4701a 100644
--- a/drivers/video/fbdev/core/fbcon_ud.c
+++ b/drivers/video/fbdev/core/fbcon_ud.c
@@ -326,50 +326,26 @@ static void ud_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	    vc->vc_cursor_type != par->p->cursor_shape ||
 	    par->cursor_state.mask == NULL ||
 	    par->cursor_reset) {
-		char *mask = kmalloc_array(w, vc->vc_font.height, GFP_ATOMIC);
-		int cur_height, size, i = 0;
-		u8 msk = 0xff;
+		unsigned char *tmp, *mask;
 
-		if (!mask)
+		tmp = kmalloc_array(vc->vc_font.height, w, GFP_ATOMIC);
+		if (!tmp)
 			return;
+		fbcon_fill_cursor_mask(par, vc, tmp);
+
+		mask = kmalloc_array(vc->vc_font.height, w, GFP_ATOMIC);
+		if (!mask) {
+			kfree(tmp);
+			return;
+		}
+		font_glyph_rotate_180(tmp, vc->vc_font.width, vc->vc_font.height, mask);
+		kfree(tmp);
 
 		kfree(par->cursor_state.mask);
-		par->cursor_state.mask = mask;
+		par->cursor_state.mask = (const char *)mask;
 
 		par->p->cursor_shape = vc->vc_cursor_type;
 		cursor.set |= FB_CUR_SETSHAPE;
-
-		switch (CUR_SIZE(par->p->cursor_shape)) {
-		case CUR_NONE:
-			cur_height = 0;
-			break;
-		case CUR_UNDERLINE:
-			cur_height = (vc->vc_font.height < 10) ? 1 : 2;
-			break;
-		case CUR_LOWER_THIRD:
-			cur_height = vc->vc_font.height/3;
-			break;
-		case CUR_LOWER_HALF:
-			cur_height = vc->vc_font.height >> 1;
-			break;
-		case CUR_TWO_THIRDS:
-			cur_height = (vc->vc_font.height << 1)/3;
-			break;
-		case CUR_BLOCK:
-		default:
-			cur_height = vc->vc_font.height;
-			break;
-		}
-
-		size = cur_height * w;
-
-		while (size--)
-			mask[i++] = msk;
-
-		size = (vc->vc_font.height - cur_height) * w;
-
-		while (size--)
-			mask[i++] = ~msk;
 	}
 
 	par->cursor_state.enable = enable && !use_sw;
-- 
2.53.0

[PATCH 10/10] fbcon: Put font-rotation state into separate struct

[Thomas Zimmermann]

Move all temporary state of the font-rotation code into the struct
rotated in struct fbcon_par. Protect it with the Kconfig symbol
CONFIG_FRAMEBUFFER_CONSOLE_ROTATION. Avoids mixing it up with fbcon's
regular state.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/video/fbdev/core/fbcon.c        |  8 ++++++--
 drivers/video/fbdev/core/fbcon.h        | 12 +++++++----
 drivers/video/fbdev/core/fbcon_ccw.c    |  8 ++++----
 drivers/video/fbdev/core/fbcon_cw.c     |  8 ++++----
 drivers/video/fbdev/core/fbcon_rotate.c | 27 +++++++++++++------------
 drivers/video/fbdev/core/fbcon_ud.c     | 10 ++++-----
 6 files changed, 41 insertions(+), 32 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 345d9aa193f0..00fa5990dfc5 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -787,7 +787,9 @@ static void fbcon_release(struct fb_info *info)
 		kfree(par->cursor_state.mask);
 		kfree(par->cursor_data);
 		kfree(par->cursor_src);
-		kfree(par->fontbuffer);
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_ROTATION
+		kfree(par->rotated.buf);
+#endif
 		kfree(info->fbcon_par);
 		info->fbcon_par = NULL;
 	}
@@ -1040,7 +1042,9 @@ static const char *fbcon_startup(void)
 	par = info->fbcon_par;
 	par->currcon = -1;
 	par->graphics = 1;
-	par->cur_rotate = -1;
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_ROTATION
+	par->rotated.buf_rotate = -1;
+#endif
 
 	p->con_rotate = initial_rotation;
 	if (p->con_rotate == -1)
diff --git a/drivers/video/fbdev/core/fbcon.h b/drivers/video/fbdev/core/fbcon.h
index bb0727b70631..5a3866b7ee33 100644
--- a/drivers/video/fbdev/core/fbcon.h
+++ b/drivers/video/fbdev/core/fbcon.h
@@ -80,13 +80,17 @@ struct fbcon_par {
 	int    graphics;
 	bool   initialized;
 	int    rotate;
-	int    cur_rotate;
 	char  *cursor_data;
-	u8          *fontbuffer;
-	const u8    *fontdata;
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_ROTATION
+	struct {
+		font_data_t *fontdata;  /* source font */
+		u8 *buf;                /* rotated glphys */
+		size_t bufsize;
+		int buf_rotate;         /* rotation of buf */
+	} rotated;
+#endif
 	u8    *cursor_src;
 	u32    cursor_size;
-	size_t fd_size;
 
 	const struct fbcon_bitops *bitops;
 };
diff --git a/drivers/video/fbdev/core/fbcon_ccw.c b/drivers/video/fbdev/core/fbcon_ccw.c
index 723d9a33067f..33f02d579e02 100644
--- a/drivers/video/fbdev/core/fbcon_ccw.c
+++ b/drivers/video/fbdev/core/fbcon_ccw.c
@@ -106,7 +106,7 @@ static inline void ccw_putcs_aligned(struct vc_data *vc, struct fb_info *info,
 	u8 *src;
 
 	while (cnt--) {
-		src = par->fontbuffer + (scr_readw(s--) & charmask) * cellsize;
+		src = par->rotated.buf + (scr_readw(s--) & charmask) * cellsize;
 
 		if (attr) {
 			ccw_update_attr(buf, src, attr, vc);
@@ -142,7 +142,7 @@ static void ccw_putcs(struct vc_data *vc, struct fb_info *info,
 	u8 *dst, *buf = NULL;
 	u32 vyres = GETVYRES(par->p, info);
 
-	if (!par->fontbuffer)
+	if (!par->rotated.buf)
 		return;
 
 	image.fg_color = fg;
@@ -232,14 +232,14 @@ static void ccw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	char *src;
 	u32 vyres = GETVYRES(par->p, info);
 
-	if (!par->fontbuffer)
+	if (!par->rotated.buf)
 		return;
 
 	cursor.set = 0;
 
  	c = scr_readw((u16 *) vc->vc_pos);
 	attribute = get_attribute(info, c);
-	src = par->fontbuffer + ((c & charmask) * (w * vc->vc_font.width));
+	src = par->rotated.buf + ((c & charmask) * (w * vc->vc_font.width));
 
 	if (par->cursor_state.image.data != src ||
 	    par->cursor_reset) {
diff --git a/drivers/video/fbdev/core/fbcon_cw.c b/drivers/video/fbdev/core/fbcon_cw.c
index 732d093d462f..bde820967eb9 100644
--- a/drivers/video/fbdev/core/fbcon_cw.c
+++ b/drivers/video/fbdev/core/fbcon_cw.c
@@ -91,7 +91,7 @@ static inline void cw_putcs_aligned(struct vc_data *vc, struct fb_info *info,
 	u8 *src;
 
 	while (cnt--) {
-		src = par->fontbuffer + (scr_readw(s++) & charmask) * cellsize;
+		src = par->rotated.buf + (scr_readw(s++) & charmask) * cellsize;
 
 		if (attr) {
 			cw_update_attr(buf, src, attr, vc);
@@ -127,7 +127,7 @@ static void cw_putcs(struct vc_data *vc, struct fb_info *info,
 	u8 *dst, *buf = NULL;
 	u32 vxres = GETVXRES(par->p, info);
 
-	if (!par->fontbuffer)
+	if (!par->rotated.buf)
 		return;
 
 	image.fg_color = fg;
@@ -215,14 +215,14 @@ static void cw_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	char *src;
 	u32 vxres = GETVXRES(par->p, info);
 
-	if (!par->fontbuffer)
+	if (!par->rotated.buf)
 		return;
 
 	cursor.set = 0;
 
  	c = scr_readw((u16 *) vc->vc_pos);
 	attribute = get_attribute(info, c);
-	src = par->fontbuffer + ((c & charmask) * (w * vc->vc_font.width));
+	src = par->rotated.buf + ((c & charmask) * (w * vc->vc_font.width));
 
 	if (par->cursor_state.image.data != src ||
 	    par->cursor_reset) {
diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index 74206f5a6e98..6cdbc96eeca6 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -18,34 +18,35 @@
 int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 {
 	struct fbcon_par *par = info->fbcon_par;
-	unsigned char *fontbuffer;
+	unsigned char *buf;
 	int ret;
 
-	if (vc->vc_font.data == par->fontdata &&
-	    par->p->con_rotate == par->cur_rotate)
+	if (par->p->fontdata == par->rotated.fontdata && par->rotate == par->rotated.buf_rotate)
 		return 0;
 
-	par->fontdata = vc->vc_font.data;
-	par->cur_rotate = par->p->con_rotate;
+	par->rotated.fontdata = par->p->fontdata;
+	par->rotated.buf_rotate = par->rotate;
 
 	if (info->fbops->fb_sync)
 		info->fbops->fb_sync(info);
 
-	fontbuffer = font_data_rotate(par->p->fontdata, vc->vc_font.width,
-				      vc->vc_font.height, vc->vc_font.charcount,
-				      par->rotate, par->fontbuffer, &par->fd_size);
-	if (IS_ERR(fontbuffer)) {
-		ret = PTR_ERR(fontbuffer);
+	buf = font_data_rotate(par->rotated.fontdata, vc->vc_font.width,
+			       vc->vc_font.height, vc->vc_font.charcount,
+			       par->rotated.buf_rotate, par->rotated.buf,
+			       &par->rotated.bufsize);
+	if (IS_ERR(buf)) {
+		ret = PTR_ERR(buf);
 		goto err_kfree;
 	}
 
-	par->fontbuffer = fontbuffer;
+	par->rotated.buf = buf;
 
 	return 0;
 
 err_kfree:
-	kfree(par->fontbuffer);
-	par->fontbuffer = NULL; /* clear here to avoid output */
+	kfree(par->rotated.buf);
+	par->rotated.buf = NULL; /* clear here to avoid output */
+	par->rotated.bufsize = 0;
 
 	return ret;
 }
diff --git a/drivers/video/fbdev/core/fbcon_ud.c b/drivers/video/fbdev/core/fbcon_ud.c
index a1981fa4701a..eaf08999e249 100644
--- a/drivers/video/fbdev/core/fbcon_ud.c
+++ b/drivers/video/fbdev/core/fbcon_ud.c
@@ -92,7 +92,7 @@ static inline void ud_putcs_aligned(struct vc_data *vc, struct fb_info *info,
 	u8 *src;
 
 	while (cnt--) {
-		src = par->fontbuffer + (scr_readw(s--) & charmask) * cellsize;
+		src = par->rotated.buf + (scr_readw(s--) & charmask) * cellsize;
 
 		if (attr) {
 			ud_update_attr(buf, src, attr, vc);
@@ -127,7 +127,7 @@ static inline void ud_putcs_unaligned(struct vc_data *vc,
 	u8 *src;
 
 	while (cnt--) {
-		src = par->fontbuffer + (scr_readw(s--) & charmask) * cellsize;
+		src = par->rotated.buf + (scr_readw(s--) & charmask) * cellsize;
 
 		if (attr) {
 			ud_update_attr(buf, src, attr, vc);
@@ -164,7 +164,7 @@ static void ud_putcs(struct vc_data *vc, struct fb_info *info,
 	u32 vyres = GETVYRES(par->p, info);
 	u32 vxres = GETVXRES(par->p, info);
 
-	if (!par->fontbuffer)
+	if (!par->rotated.buf)
 		return;
 
 	image.fg_color = fg;
@@ -262,14 +262,14 @@ static void ud_cursor(struct vc_data *vc, struct fb_info *info, bool enable,
 	u32 vyres = GETVYRES(par->p, info);
 	u32 vxres = GETVXRES(par->p, info);
 
-	if (!par->fontbuffer)
+	if (!par->rotated.buf)
 		return;
 
 	cursor.set = 0;
 
  	c = scr_readw((u16 *) vc->vc_pos);
 	attribute = get_attribute(info, c);
-	src = par->fontbuffer + ((c & charmask) * (w * vc->vc_font.height));
+	src = par->rotated.buf + ((c & charmask) * (w * vc->vc_font.height));
 
 	if (par->cursor_state.image.data != src ||
 	    par->cursor_reset) {
-- 
2.53.0