[PATCH v2 09/10] fbcon: Fill cursor mask in helper function

Thomas Zimmermann
2026-04-07T09:26:24Z

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.

v2:
- fix sparse truncated-bits warning

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..ff4c69e971f8 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 int pattern = 0xffffffff;
+ 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++ = (unsigned char)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