From 5289475d1375017ab4288b276383e9684280876d Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Fri, 2 Mar 2012 15:00:02 +0000
Subject: [PATCH] vt: tackle the main part of the selection logic
We leave the existing paste mess alone and just fix up the vt side of
things.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/vt/selection.c | 39 ++++++++++++++++++++++++++++++--------
drivers/tty/vt/vt.c | 2 ++
2 files changed, 33 insertions(+), 8 deletions(-)
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c
index 2a5091670927..8e9b4be97a2d 100644
--- a/drivers/tty/vt/selection.c
+++ b/drivers/tty/vt/selection.c
@@ -62,10 +62,14 @@ sel_pos(int n)
use_unicode);
}
-/* remove the current selection highlight, if any,
- from the console holding the selection. */
-void
-clear_selection(void) {
+/**
+ * clear_selection - remove current selection
+ *
+ * Remove the current selection highlight, if any from the console
+ * holding the selection. The caller must hold the console lock.
+ */
+void clear_selection(void)
+{
highlight_pointer(-1); /* hide the pointer */
if (sel_start != -1) {
highlight(sel_start, sel_end);
@@ -75,7 +79,7 @@ clear_selection(void) {
/*
* User settable table: what characters are to be considered alphabetic?
- * 256 bits. FIXME: Needs a locking model.
+ * 256 bits. Locked by the console lock.
*/
static u32 inwordLut[8]={
0x00000000, /* control chars */
@@ -92,10 +96,20 @@ static inline int inword(const u16 c) {
return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
}
-/* set inwordLut contents. Invoked by ioctl(). */
+/**
+ * set loadlut - load the LUT table
+ * @p: user table
+ *
+ * Load the LUT table from user space. The caller must hold the console
+ * lock. Make a temporary copy so a partial update doesn't make a mess.
+ */
int sel_loadlut(char __user *p)
{
- return copy_from_user(inwordLut, (u32 __user *)(p+4), 32) ? -EFAULT : 0;
+ u32 tmplut[8];
+ if (copy_from_user(tmplut, (u32 __user *)(p+4), 32))
+ return -EFAULT;
+ memcpy(inwordLut, tmplut, 32);
+ return 0;
}
/* does screen address p correspond to character at LH/RH edge of screen? */
@@ -131,7 +145,16 @@ static int store_utf8(u16 c, char *p)
}
}
-/* set the current selection. Invoked by ioctl() or by kernel code. */
+/**
+ * set_selection - set the current selection.
+ * @sel: user selection info
+ * @tty: the console tty
+ *
+ * Invoked by the ioctl handle for the vt layer.
+ *
+ * The entire selection process is managed under the console_lock. It's
+ * a lot under the lock but its hardly a performance path
+ */
int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
{
struct vc_data *vc = vc_cons[fg_console].d;
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index ab7385e526af..e5abceacc2d0 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -2623,7 +2623,9 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
console_unlock();
break;
case TIOCL_SELLOADLUT:
+ console_lock();
ret = sel_loadlut(p);
+ console_unlock();
break;
case TIOCL_GETSHIFTSTATE:
--
2.34.1