1 files changed, 75 insertions, 14 deletions

diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c
index e4a66e1fd05f..9c44252e52a3 100644
--- a/drivers/tty/vt/vc_screen.c
+++ b/drivers/tty/vt/vc_screen.c
@@ -10,6 +10,12 @@
  *	Attribute/character pair is in native endianity.
  *            [minor: N+128]
  *
+ * /dev/vcsuN: similar to /dev/vcsaN but using 4-byte unicode values
+ *	instead of 1-byte screen glyph values.
+ *            [minor: N+64]
+ *
+ * /dev/vcsuaN: same idea as /dev/vcsaN for unicode (not yet implemented).
+ *
  * This replaces screendump and part of selection, so that the system
  * administrator can control access using file system permissions.
  *
@@ -51,6 +57,26 @@
 
 #define CON_BUF_SIZE (CONFIG_BASE_SMALL ? 256 : PAGE_SIZE)
 
+/*
+ * Our minor space:
+ *
+ *   0 ... 63	glyph mode without attributes
+ *  64 ... 127	unicode mode without attributes
+ * 128 ... 191	glyph mode with attributes
+ * 192 ... 255	unused (reserved for unicode with attributes)
+ *
+ * This relies on MAX_NR_CONSOLES being  <= 63, meaning 63 actual consoles
+ * with minors 0, 64, 128 and 192 being proxies for the foreground console.
+ */
+#if MAX_NR_CONSOLES > 63
+#warning "/dev/vcs* devices may not accommodate more than 63 consoles"
+#endif
+
+#define console(inode)		(iminor(inode) & 63)
+#define use_unicode(inode)	(iminor(inode) & 64)
+#define use_attributes(inode)	(iminor(inode) & 128)
+
+
 struct vcs_poll_data {
 	struct notifier_block notifier;
 	unsigned int cons_num;
@@ -102,7 +128,7 @@ vcs_poll_data_get(struct file *file)
 	poll = kzalloc(sizeof(*poll), GFP_KERNEL);
 	if (!poll)
 		return NULL;
-	poll->cons_num = iminor(file_inode(file)) & 127;
+	poll->cons_num = console(file_inode(file));
 	init_waitqueue_head(&poll->waitq);
 	poll->notifier.notifier_call = vcs_notifier;
 	if (register_vt_notifier(&poll->notifier) != 0) {
@@ -140,7 +166,7 @@ vcs_poll_data_get(struct file *file)
 static struct vc_data*
 vcs_vc(struct inode *inode, int *viewed)
 {
-	unsigned int currcons = iminor(inode) & 127;
+	unsigned int currcons = console(inode);
 
 	WARN_CONSOLE_UNLOCKED();
 
@@ -164,7 +190,6 @@ static int
 vcs_size(struct inode *inode)
 {
 	int size;
-	int minor = iminor(inode);
 	struct vc_data *vc;
 
 	WARN_CONSOLE_UNLOCKED();
@@ -175,8 +200,12 @@ vcs_size(struct inode *inode)
 
 	size = vc->vc_rows * vc->vc_cols;
 
-	if (minor & 128)
+	if (use_attributes(inode)) {
+		if (use_unicode(inode))
+			return -EOPNOTSUPP;
 		size = 2*size + HEADER_SIZE;
+	} else if (use_unicode(inode))
+		size *= 4;
 	return size;
 }
 
@@ -197,12 +226,10 @@ static ssize_t
 vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 {
 	struct inode *inode = file_inode(file);
-	unsigned int currcons = iminor(inode);
 	struct vc_data *vc;
 	struct vcs_poll_data *poll;
-	long pos;
-	long attr, read;
-	int col, maxcol, viewed;
+	long pos, read;
+	int attr, uni_mode, row, col, maxcol, viewed;
 	unsigned short *org = NULL;
 	ssize_t ret;
 	char *con_buf;
@@ -218,7 +245,8 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 	 */
 	console_lock();
 
-	attr = (currcons & 128);
+	uni_mode = use_unicode(inode);
+	attr = use_attributes(inode);
 	ret = -ENXIO;
 	vc = vcs_vc(inode, &viewed);
 	if (!vc)
@@ -227,6 +255,10 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 	ret = -EINVAL;
 	if (pos < 0)
 		goto unlock_out;
+	/* we enforce 32-bit alignment for pos and count in unicode mode */
+	if (uni_mode && (pos | count) & 3)
+		goto unlock_out;
+
 	poll = file->private_data;
 	if (count && poll)
 		poll->seen_last_update = true;
@@ -266,7 +298,27 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 		con_buf_start = con_buf0 = con_buf;
 		orig_count = this_round;
 		maxcol = vc->vc_cols;
-		if (!attr) {
+		if (uni_mode) {
+			unsigned int nr;
+
+			ret = vc_uniscr_check(vc);
+			if (ret)
+				break;
+			p /= 4;
+			row = p / vc->vc_cols;
+			col = p % maxcol;
+			nr = maxcol - col;
+			do {
+				if (nr > this_round/4)
+					nr = this_round/4;
+				vc_uniscr_copy_line(vc, con_buf0, row, col, nr);
+				con_buf0 += nr * 4;
+				this_round -= nr * 4;
+				row++;
+				col = 0;
+				nr = maxcol;
+			} while (this_round);
+		} else if (!attr) {
 			org = screen_pos(vc, p, viewed);
 			col = p % maxcol;
 			p += maxcol - col;
@@ -375,7 +427,6 @@ static ssize_t
 vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 {
 	struct inode *inode = file_inode(file);
-	unsigned int currcons = iminor(inode);
 	struct vc_data *vc;
 	long pos;
 	long attr, size, written;
@@ -396,7 +447,7 @@ vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 	 */
 	console_lock();
 
-	attr = (currcons & 128);
+	attr = use_attributes(inode);
 	ret = -ENXIO;
 	vc = vcs_vc(inode, &viewed);
 	if (!vc)
@@ -593,9 +644,15 @@ vcs_fasync(int fd, struct file *file, int on)
 static int
 vcs_open(struct inode *inode, struct file *filp)
 {
-	unsigned int currcons = iminor(inode) & 127;
+	unsigned int currcons = console(inode);
+	bool attr = use_attributes(inode);
+	bool uni_mode = use_unicode(inode);
 	int ret = 0;
-	
+
+	/* we currently don't support attributes in unicode mode */
+	if (attr && uni_mode)
+		return -EOPNOTSUPP;
+
 	console_lock();
 	if(currcons && !vc_cons_allocated(currcons-1))
 		ret = -ENXIO;
@@ -628,6 +685,8 @@ void vcs_make_sysfs(int index)
 {
 	device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 1), NULL,
 		      "vcs%u", index + 1);
+	device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 65), NULL,
+		      "vcsu%u", index + 1);
 	device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 129), NULL,
 		      "vcsa%u", index + 1);
 }
@@ -635,6 +694,7 @@ void vcs_make_sysfs(int index)
 void vcs_remove_sysfs(int index)
 {
 	device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 1));
+	device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 65));
 	device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 129));
 }
 
@@ -647,6 +707,7 @@ int __init vcs_init(void)
 	vc_class = class_create(THIS_MODULE, "vc");
 
 	device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 0), NULL, "vcs");
+	device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 64), NULL, "vcsu");
 	device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 128), NULL, "vcsa");
 	for (i = 0; i < MIN_NR_CONSOLES; i++)
 		vcs_make_sysfs(i);