From: Alan Mackenzie <acm@muc.de>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jirislaby@kernel.org>,
Simona Vetter <simona@ffwll.ch>,
linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
Helge Deller <deller@gmx.de>,
Thomas Zimmermann <tzimmermann@suse.de>,
linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org
Cc: acm@muc.de
Subject: [Patch 8/9]: vt: Enhancements to the VT ioctl interface
Date: Thu, 27 Aug 2026 18:56:30 +0000 [thread overview]
Message-ID: <apCIXtwoPY_a3QOi@MAC.fritz.box> (raw)
In-Reply-To: <apCEDM2sWv_M354-@MAC.fritz.box>
vt: 32b glyph: 10. Enhancements to the VT ioctl interface
Handle the current 16-bit P/GIO_UNIMAP ioctls by converting
to/from 32-bit code-points/glyph numbers. Add handling for new
32-bit ioctls P/GIO_UNIMAP21. Convert to and from __user in
vt_ioctl.c rather than in vt.c or consolemap.c.
Signed-off-by: Alan Mackenzie <acm@muc.de>
diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c
index 28993a3d0acb..05986430e1bb 100644
--- a/drivers/tty/vt/vt_ioctl.c
+++ b/drivers/tty/vt/vt_ioctl.c
@@ -24,7 +24,6 @@
#include <linux/major.h>
#include <linux/fs.h>
#include <linux/console.h>
-#include <linux/consolemap.h>
#include <linux/signal.h>
#include <linux/suspend.h>
#include <linux/timex.h>
@@ -36,6 +35,7 @@
#include <linux/kbd_kern.h>
#include <linux/vt_kern.h>
+#include <linux/consolemap.h>
#include <linux/kbd_diacr.h>
#include <linux/selection.h>
@@ -484,10 +484,155 @@ static int vt_k_ioctl(struct tty_struct *tty, unsigned int cmd,
return 0;
}
+#ifdef CONFIG_FB_GLYPH_21BIT
+static int vt__user_unipair_8_to_21(unsigned int ct,
+ struct unipair __user *entries,
+ struct unipair21 **tmp21_entries)
+{
+ struct unipair *tmp_entries;
+ int i, ret = 0;
+
+ tmp_entries = kmalloc_array(ct, sizeof(struct unipair), GFP_KERNEL);
+ if (!tmp_entries)
+ return -ENOMEM;
+ if (copy_from_user(tmp_entries, entries, ct * sizeof(struct unipair))) {
+ ret = -EFAULT;
+ goto free_tmp;
+ }
+ *tmp21_entries = kmalloc_array(ct, sizeof(struct unipair21), GFP_KERNEL);
+ if (!*tmp21_entries) {
+ ret = -ENOMEM;
+ goto free_tmp;
+ }
+ for (i = 0; i < ct; i++) {
+ (*tmp21_entries)[i].unicode = tmp_entries[i].unicode;
+ (*tmp21_entries)[i].fontpos = tmp_entries[i].fontpos;
+ }
+free_tmp: kfree(tmp_entries);
+ return ret;
+}
+
+static int vt_unipair_21_to__user_8(unsigned int ct,
+ struct unipair21 *entries21,
+ struct unipair __user *entries)
+{
+ struct unipair *tmp_entries;
+ int i, ret = 0;
+
+ tmp_entries = kmalloc_array(ct, sizeof(struct unipair), GFP_KERNEL);
+ if (!tmp_entries)
+ return -ENOMEM;
+ for (i = 0; i < ct; i++) {
+ if ((entries21[i].unicode > 0xffff) ||
+ (entries21[i].fontpos > 0xffff)) {
+ ret = -EINVAL;
+ goto free_tmp;
+ }
+ tmp_entries[i].unicode = entries21[i].unicode;
+ tmp_entries[i].fontpos = entries21[i].fontpos;
+ }
+ if (copy_to_user(entries, tmp_entries, ct * sizeof(struct unipair)))
+ ret = -EFAULT;
+free_tmp: kfree(tmp_entries);
+ return ret;
+}
+
static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
bool perm, struct vc_data *vc)
{
struct unimapdesc tmp;
+ struct unipair21 *tmp21_entries = NULL;
+ int ret = 0, ret1 = 0;
+ unsigned int ct;
+
+ if (copy_from_user(&tmp, user_ud, sizeof(tmp)))
+ return -EFAULT;
+ switch (cmd) {
+ case PIO_UNIMAP:
+ if (!perm)
+ return -EPERM;
+ ret = vt__user_unipair_8_to_21(tmp.entry_ct, tmp.entries,
+ &tmp21_entries);
+ if (ret)
+ return ret;
+ ret = con_set_unimap(vc, tmp.entry_ct, tmp21_entries);
+ kfree(tmp21_entries);
+ return ret;
+
+ case GIO_UNIMAP:
+ if (!perm && fg_console != vc->vc_num)
+ return -EPERM;
+ tmp21_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair21),
+ GFP_KERNEL);
+ if (!tmp21_entries)
+ return -ENOMEM;
+ ret = con_get_unimap(vc, tmp.entry_ct, &ct, tmp21_entries);
+ if (ret)
+ goto free_tmp21;
+ ret = vt_unipair_21_to__user_8(ct, tmp21_entries, tmp.entries);
+free_tmp21: ret1 = put_user(ct, &user_ud->entry_ct);
+ kfree(tmp21_entries);
+ return ret ? ret : ret1;
+ }
+ return 0;
+}
+
+static inline int do_unimap_ioctl21(int cmd, struct unimapdesc21 __user *user_ud,
+ bool perm, struct vc_data *vc)
+{
+ struct unimapdesc21 tmp;
+ struct unipair21 *k_entries;
+ int ret = 0, ret1 = 0;
+
+ if (copy_from_user(&tmp, user_ud, sizeof(tmp)))
+ return -EFAULT;
+ switch (cmd) {
+ case PIO_UNIMAP21:
+ if (!perm)
+ return -EPERM;
+ k_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair21),
+ GFP_KERNEL);
+ if (!k_entries)
+ return -ENOMEM;
+ if (copy_from_user(k_entries, tmp.entries,
+ tmp.entry_ct * sizeof(struct unipair21))) {
+ ret = -EFAULT;
+ goto free_k_entries;
+ }
+ ret = con_set_unimap(vc, tmp.entry_ct, k_entries);
+free_k_entries: kfree(k_entries);
+ return ret;
+ case GIO_UNIMAP21:
+ if (!perm && fg_console != vc->vc_num)
+ return -EPERM;
+ k_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair21),
+ GFP_KERNEL);
+ if (!k_entries)
+ return -ENOMEM;
+ ret = con_get_unimap(vc, tmp.entry_ct, &tmp.entry_ct,
+ k_entries);
+ if (ret)
+ goto free_k_entries1;
+ if (copy_to_user(tmp.entries, k_entries,
+ tmp.entry_ct * sizeof(struct unipair21)))
+ ret = -EFAULT;
+free_k_entries1: ret1 = put_user(tmp.entry_ct, &user_ud->entry_ct);
+ kfree(k_entries);
+ return ret ? ret : ret1;
+ }
+ return 0;
+}
+
+#else
+static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
+ bool perm, struct vc_data *vc)
+{
+ struct unimapdesc tmp;
+ struct unipair *k_entries;
+ int ret = 0, ret1 = 0;
if (copy_from_user(&tmp, user_ud, sizeof tmp))
return -EFAULT;
@@ -495,15 +640,41 @@ static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
case PIO_UNIMAP:
if (!perm)
return -EPERM;
- return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
+ k_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair),
+ GFP_KERNEL);
+ if (!k_entries)
+ return -ENOMEM;
+ if (copy_from_user(k_entries, tmp.entries,
+ tmp.entry_ct * sizeof(struct unipair))) {
+ ret = -EFAULT;
+ goto free_k_entries;
+ }
+ ret = con_set_unimap(vc, tmp.entry_ct, k_entries);
+free_k_entries: kfree(k_entries);
+ return ret;
case GIO_UNIMAP:
if (!perm && fg_console != vc->vc_num)
return -EPERM;
- return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct),
- tmp.entries);
+ k_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair),
+ GFP_KERNEL);
+ if (!k_entries)
+ return -ENOMEM;
+ ret = con_get_unimap(vc, tmp.entry_ct, &tmp.entry_ct,
+ k_entries);
+ if (ret)
+ goto free_k_entries1;
+ if (copy_to_user(tmp.entries, k_entries,
+ tmp.entry_ct * sizeof(struct unipair)))
+ ret = -EFAULT;
+free_k_entries1: ret1 = put_user(tmp.entry_ct, &user_ud->entry_ct);
+ kfree(k_entries);
+ return ret ? ret : ret1;
}
return 0;
}
+#endif /* CONFIG_FB_GLYPH_21BIT */
static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
bool perm)
@@ -543,6 +714,12 @@ static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
case GIO_UNIMAP:
return do_unimap_ioctl(cmd, up, perm, vc);
+#ifdef CONFIG_FB_GLYPH_21BIT
+ case PIO_UNIMAP21:
+ case GIO_UNIMAP21:
+ return do_unimap_ioctl21(cmd, up, perm, vc);
+#endif
+
default:
return -ENOIOCTLCMD;
}
@@ -1026,16 +1203,20 @@ compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
}
struct compat_unimapdesc {
- unsigned short entry_ct;
+ u16 entry_ct;
compat_caddr_t entries;
};
+#ifdef CONFIG_FB_GLYPH_21BIT
static inline int
compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
int perm, struct vc_data *vc)
{
struct compat_unimapdesc tmp;
struct unipair __user *tmp_entries;
+ struct unipair21 *tmp21_entries = NULL;
+ int ret = 0, ret1 = 0;
+ unsigned int ct;
if (copy_from_user(&tmp, user_ud, sizeof tmp))
return -EFAULT;
@@ -1044,14 +1225,83 @@ compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
case PIO_UNIMAP:
if (!perm)
return -EPERM;
- return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
+ ret = vt__user_unipair_8_to_21(tmp.entry_ct, tmp_entries,
+ &tmp21_entries);
+ if (ret)
+ return ret;
+ ret = con_set_unimap(vc, tmp.entry_ct, tmp21_entries);
+ kfree(tmp21_entries);
+ return ret;
+
case GIO_UNIMAP:
if (!perm && fg_console != vc->vc_num)
return -EPERM;
- return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
+ tmp21_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair21),
+ GFP_KERNEL);
+ if (!tmp21_entries)
+ return -ENOMEM;
+ ret = con_get_unimap(vc, tmp.entry_ct, &ct, tmp21_entries);
+ if (ret)
+ goto free_tmp21;
+ ret = vt_unipair_21_to__user_8(ct, tmp21_entries, tmp_entries);
+free_tmp21: ret1 = put_user(ct, &user_ud->entry_ct);
+ kfree(tmp21_entries);
+ return ret ? ret : ret1;
+ }
+ return 0;
+}
+#else
+static inline int
+compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
+ int perm, struct vc_data *vc)
+{
+ struct compat_unimapdesc tmp;
+ struct unipair __user *tmp_entries;
+ struct unipair *k_entries;
+ int ret = 0, ret1 = 0;
+
+ if (copy_from_user(&tmp, user_ud, sizeof(tmp)))
+ return -EFAULT;
+ tmp_entries = compat_ptr(tmp.entries);
+ switch (cmd) {
+ case PIO_UNIMAP:
+ if (!perm)
+ return -EPERM;
+ k_entries = kmalloc_array(tmp.entry_ct,
+ sizeof(struct unipair),
+ GFP_KERNEL);
+ if (!k_entries)
+ return -ENOMEM;
+ if (copy_from_user(k_entries, tmp_entries,
+ tmp.entry_ct * sizeof(struct unipair))) {
+ ret = -EFAULT;
+ goto free_k_entries;
+ }
+ ret = con_set_unimap(vc, tmp.entry_ct, k_entries);
+free_k_entries: kfree(k_entries);
+ return ret;
+ case GIO_UNIMAP:
+ if (!perm && fg_console != vc->vc_num)
+ return -EPERM;
+ k_entries = kmalloc_array(tmp.entry_ct, sizeof(struct unipair),
+ GFP_KERNEL);
+ if (!k_entries)
+ return -ENOMEM;
+ ret = con_get_unimap(vc, tmp.entry_ct, &tmp.entry_ct,
+ k_entries);
+ if (ret)
+ goto free_k_entries1;
+ if (copy_to_user(tmp_entries, k_entries,
+ tmp.entry_ct * sizeof(struct unipair)))
+ ret = -EFAULT;
+free_k_entries1: ret1 = put_user(tmp.entry_ct, &user_ud->entry_ct);
+ kfree(k_entries);
+ return ret ? ret : ret1;
}
return 0;
}
+#endif /* CONFIG_FB_GLYPH_21BIT */
long vt_compat_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
diff --git a/include/uapi/linux/kd.h b/include/uapi/linux/kd.h
index 6b384065c013..342654dfbc16 100644
--- a/include/uapi/linux/kd.h
+++ b/include/uapi/linux/kd.h
@@ -56,7 +56,7 @@ typedef char scrnmap_t;
#define GIO_SCRNMAP 0x4B40 /* get screen mapping from kernel */
#define PIO_SCRNMAP 0x4B41 /* put screen mapping table in kernel */
#define GIO_UNISCRNMAP 0x4B69 /* get full Unicode screen mapping */
-#define PIO_UNISCRNMAP 0x4B6A /* set full Unicode screen mapping */
+#define PIO_UNISCRNMAP 0x4B6A /* set full Unicode screen mapping */
#define GIO_UNIMAP 0x4B66 /* get unicode-to-font mapping from kernel */
struct unipair {
@@ -67,8 +67,19 @@ struct unimapdesc {
unsigned short entry_ct;
struct unipair __user *entries;
};
+struct unipair21 {
+ unsigned int unicode;
+ unsigned int fontpos;
+};
+struct unimapdesc21 {
+ unsigned int entry_ct;
+ struct unipair21 __user *entries;
+};
#define PIO_UNIMAP 0x4B67 /* put unicode-to-font mapping in kernel */
#define PIO_UNIMAPCLR 0x4B68 /* clear table, possibly advise hash algorithm */
+#define GIO_UNIMAP21 0x4B6E /* get 21-bit unicode-to-font mapping from kernel */
+#define PIO_UNIMAP21 0x4B6F /* put 21-bit unicode-to-font mapping to kernel */
+
struct unimapinit {
unsigned short advised_hashsize; /* 0 if no opinion */
unsigned short advised_hashstep; /* 0 if no opinion */
@@ -185,6 +196,6 @@ struct console_font {
/* note: 0x4B00-0x4B4E all have had a value at some time;
don't reuse for the time being */
-/* note: 0x4B60-0x4B6D, 0x4B70-0x4B72 used above */
+/* note: 0x4B60-0x4B6F, 0x4B70-0x4B72 used above */
#endif /* _UAPI_LINUX_KD_H */
diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h
index d008c3d0a9bb..af99aeefe177 100644
--- a/include/linux/vt_kern.h
+++ b/include/linux/vt_kern.h
@@ -90,13 +96,13 @@ static inline int con_clear_unimap(struct vc_data *vc)
return 0;
}
static inline
-int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)
+int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair *list)
{
return 0;
}
static inline
-int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct,
- struct unipair __user *list)
+int con_get_unimap(struct vc_data *vc, ushort ct, ushort *uct,
+ struct unipair *list)
{
return -EINVAL;
}
--
Alan Mackenzie (Nuremberg, Germany).
next prev parent reply other threads:[~2026-08-27 18:56 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-27 18:38 vt: Enlarge the framebuffer glyph size from 16 to 32 bits Alan Mackenzie
2026-08-27 18:42 ` [Patch 1/9]: Make consolemap.c handle Unicode planes outside BMP Alan Mackenzie
2026-08-28 4:57 ` Jiri Slaby
2026-08-27 18:45 ` [Patch 2/9]: Glyph size: Use GLYPH_SZ/HW rather than hardcoded 2, 1 Alan Mackenzie
2026-08-27 18:47 ` [Patch 3/9]: Replace scr_readw/writew by scr_readg/writeg, etc Alan Mackenzie
2026-08-27 18:48 ` [Patch 4/9]: Amend internal manipulation of glyph structure Alan Mackenzie
2026-08-27 18:50 ` [Patch 5/9]: vt: Amend three Kconfig files Alan Mackenzie
2026-08-27 18:52 ` [Patch 6/9]: vt: Use u32 and typedef u1632 to handle whole glyphs Alan Mackenzie
2026-08-27 18:54 ` [Patch 7/9]: vt: Handle up to 2^21 glyphs, rather than 256/512 Alan Mackenzie
2026-08-27 18:56 ` Alan Mackenzie [this message]
2026-08-27 18:58 ` [Patch 9/9]: vt: Misc changes, e.g. to #include directives Alan Mackenzie
2026-08-28 6:12 ` vt: Enlarge the framebuffer glyph size from 16 to 32 bits Thomas Zimmermann
2026-08-28 14:36 ` Alan Mackenzie
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=apCIXtwoPY_a3QOi@MAC.fritz.box \
--to=acm@muc.de \
--cc=deller@gmx.de \
--cc=dri-devel@lists.freedesktop.org \
--cc=gregkh@linuxfoundation.org \
--cc=jirislaby@kernel.org \
--cc=linux-fbdev@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=simona@ffwll.ch \
--cc=tzimmermann@suse.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®