[PATCH 1/5] console: Delete unused con_font_copy() callback implementations

[PATCH 1/5] console: Delete unused con_font_copy() callback implementations

[Peilin Ye]

Recently in commit 3c4e0dff2095 ("vt: Disable KD_FONT_OP_COPY") we
disabled the KD_FONT_OP_COPY ioctl() option. Delete all the
con_font_copy() callbacks, since we no longer use them.

Mark KD_FONT_OP_COPY as "obsolete" in include/uapi/linux/kd.h, just like
what we have done for PPPIOCDETACH in commit af8d3c7c001a ("ppp: remove
the PPPIOCDETACH ioctl").

Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
---
 drivers/usb/misc/sisusbvga/sisusb_con.c |  6 ------
 drivers/video/console/dummycon.c        |  6 ------
 drivers/video/fbdev/core/fbcon.c        | 11 -----------
 include/linux/console.h                 |  1 -
 include/uapi/linux/kd.h                 |  2 +-
 5 files changed, 1 insertion(+), 25 deletions(-)

diff --git a/drivers/usb/misc/sisusbvga/sisusb_con.c b/drivers/usb/misc/sisusbvga/sisusb_con.c
index c63e545fb105..fd9954381fbf 100644
--- a/drivers/usb/misc/sisusbvga/sisusb_con.c
+++ b/drivers/usb/misc/sisusbvga/sisusb_con.c
@@ -1358,11 +1358,6 @@ static int sisusbdummycon_font_default(struct vc_data *vc,
 	return 0;
 }
 
-static int sisusbdummycon_font_copy(struct vc_data *vc, int con)
-{
-	return 0;
-}
-
 static const struct consw sisusb_dummy_con = {
 	.owner =		THIS_MODULE,
 	.con_startup =		sisusbdummycon_startup,
@@ -1377,7 +1372,6 @@ static const struct consw sisusb_dummy_con = {
 	.con_blank =		sisusbdummycon_blank,
 	.con_font_set =		sisusbdummycon_font_set,
 	.con_font_default =	sisusbdummycon_font_default,
-	.con_font_copy =	sisusbdummycon_font_copy,
 };
 
 int
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 2a0d0bda7faa..ab3df752fb57 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -136,11 +136,6 @@ static int dummycon_font_default(struct vc_data *vc,
 	return 0;
 }
 
-static int dummycon_font_copy(struct vc_data *vc, int con)
-{
-	return 0;
-}
-
 /*
  *  The console `switch' structure for the dummy console
  *
@@ -161,6 +156,5 @@ const struct consw dummy_con = {
 	.con_blank =	dummycon_blank,
 	.con_font_set =	dummycon_font_set,
 	.con_font_default =	dummycon_font_default,
-	.con_font_copy =	dummycon_font_copy,
 };
 EXPORT_SYMBOL_GPL(dummy_con);
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index cef437817b0d..26d1b0916692 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2451,16 +2451,6 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
 	return 0;
 }
 
-static int fbcon_copy_font(struct vc_data *vc, int con)
-{
-	struct fbcon_display *od = &fb_display[con];
-	struct console_font *f = &vc->vc_font;
-
-	if (od->fontdata == f->data)
-		return 0;	/* already the same font... */
-	return fbcon_do_set_font(vc, f->width, f->height, od->fontdata, od->userfont);
-}
-
 /*
  *  User asked to set font; we are guaranteed that
  *	a) width and height are in range 1..32
@@ -3111,7 +3101,6 @@ static const struct consw fb_con = {
 	.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_invert_region 	= fbcon_invert_region,
 	.con_screen_pos 	= fbcon_screen_pos,
diff --git a/include/linux/console.h b/include/linux/console.h
index 4b1e26c4cb42..20874db50bc8 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -62,7 +62,6 @@ struct consw {
 	int	(*con_font_get)(struct vc_data *vc, struct console_font *font);
 	int	(*con_font_default)(struct vc_data *vc,
 			struct console_font *font, char *name);
-	int	(*con_font_copy)(struct vc_data *vc, int con);
 	int     (*con_resize)(struct vc_data *vc, unsigned int width,
 			unsigned int height, unsigned int user);
 	void	(*con_set_palette)(struct vc_data *vc,
diff --git a/include/uapi/linux/kd.h b/include/uapi/linux/kd.h
index 4616b31f84da..ee929ece4112 100644
--- a/include/uapi/linux/kd.h
+++ b/include/uapi/linux/kd.h
@@ -173,7 +173,7 @@ struct console_font {
 #define KD_FONT_OP_SET		0	/* Set font */
 #define KD_FONT_OP_GET		1	/* Get font */
 #define KD_FONT_OP_SET_DEFAULT	2	/* Set font to default, data points to name / NULL */
-#define KD_FONT_OP_COPY		3	/* Copy from another console */
+#define KD_FONT_OP_COPY		3	/* Obsolete, do not use */
 
 #define KD_FONT_FLAG_DONT_RECALC 	1	/* Don't recalculate hw charcell size [compat] */
 
-- 
2.25.1

[PATCH v3 2/5] console: Delete dummy con_font_set() and con_font_default() callback implementations

[Peilin Ye]

.con_font_set and .con_font_default callbacks should not pass `struct
console_font *` as a parameter, since `struct console_font` is a UAPI
structure.

We are trying to let them use our new kernel font descriptor, `struct
font_desc` instead. To make that work slightly easier, first delete all of
their no-op implementations used by dummy consoles.

This will make KD_FONT_OP_SET and KD_FONT_OP_SET_DEFAULT ioctl() requests
on dummy consoles start to fail and return `-ENOSYS`, which is intended,
since no user should ever expect such operations to succeed on dummy
consoles.

Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
v2: https://lore.kernel.org/lkml/c5563eeea36aae7bd72ea2e985bc610d585ece40.1604306433.git.yepeilin.cs@gmail.com/

Strictly speaking this is different from v2 (see changelog), but it really
shouldn't matter, so I'm keeping Greg's "Reviewed-by:".

Changes in v3:
  - Improve commit message. (Jiri)
  - Do not delete con_font_copy() callbacks, since they have been deleted
    in patch "console: Delete unused con_font_copy() callback
    implementations".

Change in v2:
  - Do not Cc: stable.

 drivers/usb/misc/sisusbvga/sisusb_con.c | 15 ---------------
 drivers/video/console/dummycon.c        | 14 --------------
 2 files changed, 29 deletions(-)

diff --git a/drivers/usb/misc/sisusbvga/sisusb_con.c b/drivers/usb/misc/sisusbvga/sisusb_con.c
index fd9954381fbf..dfa0d5ce6012 100644
--- a/drivers/usb/misc/sisusbvga/sisusb_con.c
+++ b/drivers/usb/misc/sisusbvga/sisusb_con.c
@@ -1345,19 +1345,6 @@ static int sisusbdummycon_blank(struct vc_data *vc, int blank, int mode_switch)
 	return 0;
 }
 
-static int sisusbdummycon_font_set(struct vc_data *vc,
-				   struct console_font *font,
-				   unsigned int flags)
-{
-	return 0;
-}
-
-static int sisusbdummycon_font_default(struct vc_data *vc,
-				       struct console_font *font, char *name)
-{
-	return 0;
-}
-
 static const struct consw sisusb_dummy_con = {
 	.owner =		THIS_MODULE,
 	.con_startup =		sisusbdummycon_startup,
@@ -1370,8 +1357,6 @@ static const struct consw sisusb_dummy_con = {
 	.con_scroll =		sisusbdummycon_scroll,
 	.con_switch =		sisusbdummycon_switch,
 	.con_blank =		sisusbdummycon_blank,
-	.con_font_set =		sisusbdummycon_font_set,
-	.con_font_default =	sisusbdummycon_font_default,
 };
 
 int
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index ab3df752fb57..f1711b2f9ff0 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -124,18 +124,6 @@ static int dummycon_switch(struct vc_data *vc)
 	return 0;
 }
 
-static int dummycon_font_set(struct vc_data *vc, struct console_font *font,
-			     unsigned int flags)
-{
-	return 0;
-}
-
-static int dummycon_font_default(struct vc_data *vc,
-				 struct console_font *font, char *name)
-{
-	return 0;
-}
-
 /*
  *  The console `switch' structure for the dummy console
  *
@@ -154,7 +142,5 @@ const struct consw dummy_con = {
 	.con_scroll =	dummycon_scroll,
 	.con_switch =	dummycon_switch,
 	.con_blank =	dummycon_blank,
-	.con_font_set =	dummycon_font_set,
-	.con_font_default =	dummycon_font_default,
 };
 EXPORT_SYMBOL_GPL(dummy_con);
-- 
2.25.1