Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c
index 7556139..f245a5a 100644
--- a/drivers/tty/vt/selection.c
+++ b/drivers/tty/vt/selection.c
@@ -35,18 +35,18 @@
 /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
 #define isspace(c)	((c) == ' ')
 
-extern void poke_blanked_console(void);
-
 /* FIXME: all this needs locking */
-/* Variables for selection control. */
-/* Use a dynamic buffer, instead of static (Dec 1994) */
-struct vc_data *sel_cons;		/* must not be deallocated */
-static int use_unicode;
-static volatile int sel_start = -1; 	/* cleared by clear_selection */
-static int sel_end;
-static int sel_buffer_lth;
-static char *sel_buffer;
-static DEFINE_MUTEX(sel_lock);
+static struct vc_selection {
+	struct mutex lock;
+	struct vc_data *cons;			/* must not be deallocated */
+	char *buffer;
+	unsigned int buf_len;
+	volatile int start;			/* cleared by clear_selection */
+	int end;
+} vc_sel = {
+	.lock = __MUTEX_INITIALIZER(vc_sel.lock),
+	.start = -1,
+};
 
 /* clear_selection, highlight and highlight_pointer can be called
    from interrupt (via scrollback/front) */
@@ -54,22 +54,21 @@
 /* set reverse video on characters s-e of console with selection. */
 static inline void highlight(const int s, const int e)
 {
-	invert_screen(sel_cons, s, e-s+2, 1);
+	invert_screen(vc_sel.cons, s, e-s+2, true);
 }
 
 /* use complementary color to show the pointer */
 static inline void highlight_pointer(const int where)
 {
-	complement_pos(sel_cons, where);
+	complement_pos(vc_sel.cons, where);
 }
 
 static u32
-sel_pos(int n)
+sel_pos(int n, bool unicode)
 {
-	if (use_unicode)
-		return screen_glyph_unicode(sel_cons, n / 2);
-	return inverse_translate(sel_cons, screen_glyph(sel_cons, n),
-				0);
+	if (unicode)
+		return screen_glyph_unicode(vc_sel.cons, n / 2);
+	return inverse_translate(vc_sel.cons, screen_glyph(vc_sel.cons, n), 0);
 }
 
 /**
@@ -81,16 +80,16 @@
 void clear_selection(void)
 {
 	highlight_pointer(-1); /* hide the pointer */
-	if (sel_start != -1) {
-		highlight(sel_start, sel_end);
-		sel_start = -1;
+	if (vc_sel.start != -1) {
+		highlight(vc_sel.start, vc_sel.end);
+		vc_sel.start = -1;
 	}
 }
 EXPORT_SYMBOL_GPL(clear_selection);
 
 bool vc_is_sel(struct vc_data *vc)
 {
-	return vc == sel_cons;
+	return vc == vc_sel.cons;
 }
 
 /*
@@ -186,151 +185,33 @@
 	return set_selection_kernel(&v, tty);
 }
 
-static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
+static int vc_selection_store_chars(struct vc_data *vc, bool unicode)
 {
-	struct vc_data *vc = vc_cons[fg_console].d;
-	int new_sel_start, new_sel_end, spc;
 	char *bp, *obp;
-	int i, ps, pe, multiplier;
-	u32 c;
-	int mode, ret = 0;
-
-	poke_blanked_console();
-
-	v->xs = min_t(u16, v->xs - 1, vc->vc_cols - 1);
-	v->ys = min_t(u16, v->ys - 1, vc->vc_rows - 1);
-	v->xe = min_t(u16, v->xe - 1, vc->vc_cols - 1);
-	v->ye = min_t(u16, v->ye - 1, vc->vc_rows - 1);
-	ps = v->ys * vc->vc_size_row + (v->xs << 1);
-	pe = v->ye * vc->vc_size_row + (v->xe << 1);
-
-	if (v->sel_mode == TIOCL_SELCLEAR) {
-		/* useful for screendump without selection highlights */
-		clear_selection();
-		return 0;
-	}
-
-	if (mouse_reporting() && (v->sel_mode & TIOCL_SELMOUSEREPORT)) {
-		mouse_report(tty, v->sel_mode & TIOCL_SELBUTTONMASK, v->xs,
-			     v->ys);
-		return 0;
-	}
-
-	if (ps > pe)	/* make sel_start <= sel_end */
-		swap(ps, pe);
-
-	if (sel_cons != vc_cons[fg_console].d) {
-		clear_selection();
-		sel_cons = vc_cons[fg_console].d;
-	}
-	mode = vt_do_kdgkbmode(fg_console);
-	if (mode == K_UNICODE)
-		use_unicode = 1;
-	else
-		use_unicode = 0;
-
-	switch (v->sel_mode)
-	{
-		case TIOCL_SELCHAR:	/* character-by-character selection */
-			new_sel_start = ps;
-			new_sel_end = pe;
-			break;
-		case TIOCL_SELWORD:	/* word-by-word selection */
-			spc = isspace(sel_pos(ps));
-			for (new_sel_start = ps; ; ps -= 2)
-			{
-				if ((spc && !isspace(sel_pos(ps))) ||
-				    (!spc && !inword(sel_pos(ps))))
-					break;
-				new_sel_start = ps;
-				if (!(ps % vc->vc_size_row))
-					break;
-			}
-			spc = isspace(sel_pos(pe));
-			for (new_sel_end = pe; ; pe += 2)
-			{
-				if ((spc && !isspace(sel_pos(pe))) ||
-				    (!spc && !inword(sel_pos(pe))))
-					break;
-				new_sel_end = pe;
-				if (!((pe + 2) % vc->vc_size_row))
-					break;
-			}
-			break;
-		case TIOCL_SELLINE:	/* line-by-line selection */
-			new_sel_start = ps - ps % vc->vc_size_row;
-			new_sel_end = pe + vc->vc_size_row
-				    - pe % vc->vc_size_row - 2;
-			break;
-		case TIOCL_SELPOINTER:
-			highlight_pointer(pe);
-			return 0;
-		default:
-			return -EINVAL;
-	}
-
-	/* remove the pointer */
-	highlight_pointer(-1);
-
-	/* select to end of line if on trailing space */
-	if (new_sel_end > new_sel_start &&
-		!atedge(new_sel_end, vc->vc_size_row) &&
-		isspace(sel_pos(new_sel_end))) {
-		for (pe = new_sel_end + 2; ; pe += 2)
-			if (!isspace(sel_pos(pe)) ||
-			    atedge(pe, vc->vc_size_row))
-				break;
-		if (isspace(sel_pos(pe)))
-			new_sel_end = pe;
-	}
-	if (sel_start == -1)	/* no current selection */
-		highlight(new_sel_start, new_sel_end);
-	else if (new_sel_start == sel_start)
-	{
-		if (new_sel_end == sel_end)	/* no action required */
-			return 0;
-		else if (new_sel_end > sel_end)	/* extend to right */
-			highlight(sel_end + 2, new_sel_end);
-		else				/* contract from right */
-			highlight(new_sel_end + 2, sel_end);
-	}
-	else if (new_sel_end == sel_end)
-	{
-		if (new_sel_start < sel_start)	/* extend to left */
-			highlight(new_sel_start, sel_start - 2);
-		else				/* contract from left */
-			highlight(sel_start, new_sel_start - 2);
-	}
-	else	/* some other case; start selection from scratch */
-	{
-		clear_selection();
-		highlight(new_sel_start, new_sel_end);
-	}
-	sel_start = new_sel_start;
-	sel_end = new_sel_end;
+	unsigned int i;
 
 	/* Allocate a new buffer before freeing the old one ... */
-	multiplier = use_unicode ? 4 : 1;  /* chars can take up to 4 bytes */
-	bp = kmalloc_array((sel_end - sel_start) / 2 + 1, multiplier,
-			   GFP_KERNEL);
+	/* chars can take up to 4 bytes with unicode */
+	bp = kmalloc_array((vc_sel.end - vc_sel.start) / 2 + 1, unicode ? 4 : 1,
+			   GFP_KERNEL | __GFP_NOWARN);
 	if (!bp) {
 		printk(KERN_WARNING "selection: kmalloc() failed\n");
 		clear_selection();
 		return -ENOMEM;
 	}
-	kfree(sel_buffer);
-	sel_buffer = bp;
+	kfree(vc_sel.buffer);
+	vc_sel.buffer = bp;
 
 	obp = bp;
-	for (i = sel_start; i <= sel_end; i += 2) {
-		c = sel_pos(i);
-		if (use_unicode)
+	for (i = vc_sel.start; i <= vc_sel.end; i += 2) {
+		u32 c = sel_pos(i, unicode);
+		if (unicode)
 			bp += store_utf8(c, bp);
 		else
 			*bp++ = c;
 		if (!isspace(c))
 			obp = bp;
-		if (! ((i + 2) % vc->vc_size_row)) {
+		if (!((i + 2) % vc->vc_size_row)) {
 			/* strip trailing blanks from line and add newline,
 			   unless non-space at end of line. */
 			if (obp != bp) {
@@ -340,20 +221,144 @@
 			obp = bp;
 		}
 	}
-	sel_buffer_lth = bp - sel_buffer;
+	vc_sel.buf_len = bp - vc_sel.buffer;
 
-	return ret;
+	return 0;
+}
+
+static int vc_do_selection(struct vc_data *vc, unsigned short mode, int ps,
+		int pe)
+{
+	int new_sel_start, new_sel_end, spc;
+	bool unicode = vt_do_kdgkbmode(fg_console) == K_UNICODE;
+
+	switch (mode) {
+	case TIOCL_SELCHAR:	/* character-by-character selection */
+		new_sel_start = ps;
+		new_sel_end = pe;
+		break;
+	case TIOCL_SELWORD:	/* word-by-word selection */
+		spc = isspace(sel_pos(ps, unicode));
+		for (new_sel_start = ps; ; ps -= 2) {
+			if ((spc && !isspace(sel_pos(ps, unicode))) ||
+			    (!spc && !inword(sel_pos(ps, unicode))))
+				break;
+			new_sel_start = ps;
+			if (!(ps % vc->vc_size_row))
+				break;
+		}
+
+		spc = isspace(sel_pos(pe, unicode));
+		for (new_sel_end = pe; ; pe += 2) {
+			if ((spc && !isspace(sel_pos(pe, unicode))) ||
+			    (!spc && !inword(sel_pos(pe, unicode))))
+				break;
+			new_sel_end = pe;
+			if (!((pe + 2) % vc->vc_size_row))
+				break;
+		}
+		break;
+	case TIOCL_SELLINE:	/* line-by-line selection */
+		new_sel_start = rounddown(ps, vc->vc_size_row);
+		new_sel_end = rounddown(pe, vc->vc_size_row) +
+			vc->vc_size_row - 2;
+		break;
+	case TIOCL_SELPOINTER:
+		highlight_pointer(pe);
+		return 0;
+	default:
+		return -EINVAL;
+	}
+
+	/* remove the pointer */
+	highlight_pointer(-1);
+
+	/* select to end of line if on trailing space */
+	if (new_sel_end > new_sel_start &&
+		!atedge(new_sel_end, vc->vc_size_row) &&
+		isspace(sel_pos(new_sel_end, unicode))) {
+		for (pe = new_sel_end + 2; ; pe += 2)
+			if (!isspace(sel_pos(pe, unicode)) ||
+			    atedge(pe, vc->vc_size_row))
+				break;
+		if (isspace(sel_pos(pe, unicode)))
+			new_sel_end = pe;
+	}
+	if (vc_sel.start == -1)	/* no current selection */
+		highlight(new_sel_start, new_sel_end);
+	else if (new_sel_start == vc_sel.start)
+	{
+		if (new_sel_end == vc_sel.end)	/* no action required */
+			return 0;
+		else if (new_sel_end > vc_sel.end)	/* extend to right */
+			highlight(vc_sel.end + 2, new_sel_end);
+		else				/* contract from right */
+			highlight(new_sel_end + 2, vc_sel.end);
+	}
+	else if (new_sel_end == vc_sel.end)
+	{
+		if (new_sel_start < vc_sel.start) /* extend to left */
+			highlight(new_sel_start, vc_sel.start - 2);
+		else				/* contract from left */
+			highlight(vc_sel.start, new_sel_start - 2);
+	}
+	else	/* some other case; start selection from scratch */
+	{
+		clear_selection();
+		highlight(new_sel_start, new_sel_end);
+	}
+	vc_sel.start = new_sel_start;
+	vc_sel.end = new_sel_end;
+
+	return vc_selection_store_chars(vc, unicode);
+}
+
+static int vc_selection(struct vc_data *vc, struct tiocl_selection *v,
+		struct tty_struct *tty)
+{
+	int ps, pe;
+
+	poke_blanked_console();
+
+	if (v->sel_mode == TIOCL_SELCLEAR) {
+		/* useful for screendump without selection highlights */
+		clear_selection();
+		return 0;
+	}
+
+	v->xs = min_t(u16, v->xs - 1, vc->vc_cols - 1);
+	v->ys = min_t(u16, v->ys - 1, vc->vc_rows - 1);
+	v->xe = min_t(u16, v->xe - 1, vc->vc_cols - 1);
+	v->ye = min_t(u16, v->ye - 1, vc->vc_rows - 1);
+
+	if (mouse_reporting() && (v->sel_mode & TIOCL_SELMOUSEREPORT)) {
+		mouse_report(tty, v->sel_mode & TIOCL_SELBUTTONMASK, v->xs,
+			     v->ys);
+		return 0;
+	}
+
+	ps = v->ys * vc->vc_size_row + (v->xs << 1);
+	pe = v->ye * vc->vc_size_row + (v->xe << 1);
+	if (ps > pe)	/* make vc_sel.start <= vc_sel.end */
+		swap(ps, pe);
+
+	if (vc_sel.cons != vc) {
+		clear_selection();
+		vc_sel.cons = vc;
+	}
+
+	return vc_do_selection(vc, v->sel_mode, ps, pe);
 }
 
 int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
 {
 	int ret;
 
-	mutex_lock(&sel_lock);
+	mutex_lock(&vc_sel.lock);
 	console_lock();
-	ret = __set_selection_kernel(v, tty);
+	ret = vc_selection(vc_cons[fg_console].d, v, tty);
 	console_unlock();
-	mutex_unlock(&sel_lock);
+	mutex_unlock(&vc_sel.lock);
 
 	return ret;
 }
@@ -385,26 +390,26 @@
 	tty_buffer_lock_exclusive(&vc->port);
 
 	add_wait_queue(&vc->paste_wait, &wait);
-	mutex_lock(&sel_lock);
-	while (sel_buffer && sel_buffer_lth > pasted) {
+	mutex_lock(&vc_sel.lock);
+	while (vc_sel.buffer && vc_sel.buf_len > pasted) {
 		set_current_state(TASK_INTERRUPTIBLE);
 		if (signal_pending(current)) {
 			ret = -EINTR;
 			break;
 		}
 		if (tty_throttled(tty)) {
-			mutex_unlock(&sel_lock);
+			mutex_unlock(&vc_sel.lock);
 			schedule();
-			mutex_lock(&sel_lock);
+			mutex_lock(&vc_sel.lock);
 			continue;
 		}
 		__set_current_state(TASK_RUNNING);
-		count = sel_buffer_lth - pasted;
-		count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
+		count = vc_sel.buf_len - pasted;
+		count = tty_ldisc_receive_buf(ld, vc_sel.buffer + pasted, NULL,
 					      count);
 		pasted += count;
 	}
-	mutex_unlock(&sel_lock);
+	mutex_unlock(&vc_sel.lock);
 	remove_wait_queue(&vc->paste_wait, &wait);
 	__set_current_state(TASK_RUNNING);