Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/drivers/s390/char/sclp_tty.c b/drivers/s390/char/sclp_tty.c
new file mode 100644
index 0000000..a20d7c8
--- /dev/null
+++ b/drivers/s390/char/sclp_tty.c
@@ -0,0 +1,813 @@
+/*
+ *  drivers/s390/char/sclp_tty.c
+ *    SCLP line mode terminal driver.
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Peschke <mpeschke@de.ibm.com>
+ *		 Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <asm/uaccess.h>
+
+#include "ctrlchar.h"
+#include "sclp.h"
+#include "sclp_rw.h"
+#include "sclp_tty.h"
+
+#define SCLP_TTY_PRINT_HEADER "sclp tty driver: "
+
+/*
+ * size of a buffer that collects single characters coming in
+ * via sclp_tty_put_char()
+ */
+#define SCLP_TTY_BUF_SIZE 512
+
+/*
+ * There is exactly one SCLP terminal, so we can keep things simple
+ * and allocate all variables statically.
+ */
+
+/* Lock to guard over changes to global variables. */
+static spinlock_t sclp_tty_lock;
+/* List of free pages that can be used for console output buffering. */
+static struct list_head sclp_tty_pages;
+/* List of full struct sclp_buffer structures ready for output. */
+static struct list_head sclp_tty_outqueue;
+/* Counter how many buffers are emitted. */
+static int sclp_tty_buffer_count;
+/* Pointer to current console buffer. */
+static struct sclp_buffer *sclp_ttybuf;
+/* Timer for delayed output of console messages. */
+static struct timer_list sclp_tty_timer;
+/* Waitqueue to wait for buffers to get empty. */
+static wait_queue_head_t sclp_tty_waitq;
+
+static struct tty_struct *sclp_tty;
+static unsigned char sclp_tty_chars[SCLP_TTY_BUF_SIZE];
+static unsigned short int sclp_tty_chars_count;
+
+struct tty_driver *sclp_tty_driver;
+
+extern struct termios  tty_std_termios;
+
+static struct sclp_ioctls sclp_ioctls;
+static struct sclp_ioctls sclp_ioctls_init =
+{
+	8,			/* 1 hor. tab. = 8 spaces */
+	0,			/* no echo of input by this driver */
+	80,			/* 80 characters/line */
+	1,			/* write after 1/10 s without final new line */
+	MAX_KMEM_PAGES,		/* quick fix: avoid __alloc_pages */
+	MAX_KMEM_PAGES,		/* take 32/64 pages from kernel memory, */
+	0,			/* do not convert to lower case */
+	0x6c			/* to seprate upper and lower case */
+				/* ('%' in EBCDIC) */
+};
+
+/* This routine is called whenever we try to open a SCLP terminal. */
+static int
+sclp_tty_open(struct tty_struct *tty, struct file *filp)
+{
+	sclp_tty = tty;
+	tty->driver_data = NULL;
+	tty->low_latency = 0;
+	return 0;
+}
+
+/* This routine is called when the SCLP terminal is closed. */
+static void
+sclp_tty_close(struct tty_struct *tty, struct file *filp)
+{
+	if (tty->count > 1)
+		return;
+	sclp_tty = NULL;
+}
+
+/* execute commands to control the i/o behaviour of the SCLP tty at runtime */
+static int
+sclp_tty_ioctl(struct tty_struct *tty, struct file * file,
+	       unsigned int cmd, unsigned long arg)
+{
+	unsigned long flags;
+	unsigned int obuf;
+	int check;
+	int rc;
+
+	if (tty->flags & (1 << TTY_IO_ERROR))
+		return -EIO;
+	rc = 0;
+	check = 0;
+	switch (cmd) {
+	case TIOCSCLPSHTAB:
+		/* set width of horizontal tab	*/
+		if (get_user(sclp_ioctls.htab, (unsigned short __user *) arg))
+			rc = -EFAULT;
+		else
+			check = 1;
+		break;
+	case TIOCSCLPGHTAB:
+		/* get width of horizontal tab	*/
+		if (put_user(sclp_ioctls.htab, (unsigned short __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSECHO:
+		/* enable/disable echo of input */
+		if (get_user(sclp_ioctls.echo, (unsigned char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPGECHO:
+		/* Is echo of input enabled ?  */
+		if (put_user(sclp_ioctls.echo, (unsigned char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSCOLS:
+		/* set number of columns for output  */
+		if (get_user(sclp_ioctls.columns, (unsigned short __user *) arg))
+			rc = -EFAULT;
+		else
+			check = 1;
+		break;
+	case TIOCSCLPGCOLS:
+		/* get number of columns for output  */
+		if (put_user(sclp_ioctls.columns, (unsigned short __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSNL:
+		/* enable/disable writing without final new line character  */
+		if (get_user(sclp_ioctls.final_nl, (signed char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPGNL:
+		/* Is writing without final new line character enabled ?  */
+		if (put_user(sclp_ioctls.final_nl, (signed char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSOBUF:
+		/*
+		 * set the maximum buffers size for output, will be rounded
+		 * up to next 4kB boundary and stored as number of SCCBs
+		 * (4kB Buffers) limitation: 256 x 4kB
+		 */
+		if (get_user(obuf, (unsigned int __user *) arg) == 0) {
+			if (obuf & 0xFFF)
+				sclp_ioctls.max_sccb = (obuf >> 12) + 1;
+			else
+				sclp_ioctls.max_sccb = (obuf >> 12);
+		} else
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPGOBUF:
+		/* get the maximum buffers size for output  */
+		obuf = sclp_ioctls.max_sccb << 12;
+		if (put_user(obuf, (unsigned int __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPGKBUF:
+		/* get the number of buffers got from kernel at startup */
+		if (put_user(sclp_ioctls.kmem_sccb, (unsigned short __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSCASE:
+		/* enable/disable conversion from upper to lower case */
+		if (get_user(sclp_ioctls.tolower, (unsigned char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPGCASE:
+		/* Is conversion from upper to lower case of input enabled? */
+		if (put_user(sclp_ioctls.tolower, (unsigned char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSDELIM:
+		/*
+		 * set special character used for separating upper and
+		 * lower case, 0x00 disables this feature
+		 */
+		if (get_user(sclp_ioctls.delim, (unsigned char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPGDELIM:
+		/*
+		 * get special character used for separating upper and
+		 * lower case, 0x00 disables this feature
+		 */
+		if (put_user(sclp_ioctls.delim, (unsigned char __user *) arg))
+			rc = -EFAULT;
+		break;
+	case TIOCSCLPSINIT:
+		/* set initial (default) sclp ioctls  */
+		sclp_ioctls = sclp_ioctls_init;
+		check = 1;
+		break;
+	default:
+		rc = -ENOIOCTLCMD;
+		break;
+	}
+	if (check) {
+		spin_lock_irqsave(&sclp_tty_lock, flags);
+		if (sclp_ttybuf != NULL) {
+			sclp_set_htab(sclp_ttybuf, sclp_ioctls.htab);
+			sclp_set_columns(sclp_ttybuf, sclp_ioctls.columns);
+		}
+		spin_unlock_irqrestore(&sclp_tty_lock, flags);
+	}
+	return rc;
+}
+
+/*
+ * This routine returns the numbers of characters the tty driver
+ * will accept for queuing to be written.  This number is subject
+ * to change as output buffers get emptied, or if the output flow
+ * control is acted. This is not an exact number because not every
+ * character needs the same space in the sccb. The worst case is
+ * a string of newlines. Every newlines creates a new mto which
+ * needs 8 bytes.
+ */
+static int
+sclp_tty_write_room (struct tty_struct *tty)
+{
+	unsigned long flags;
+	struct list_head *l;
+	int count;
+
+	spin_lock_irqsave(&sclp_tty_lock, flags);
+	count = 0;
+	if (sclp_ttybuf != NULL)
+		count = sclp_buffer_space(sclp_ttybuf) / sizeof(struct mto);
+	list_for_each(l, &sclp_tty_pages)
+		count += NR_EMPTY_MTO_PER_SCCB;
+	spin_unlock_irqrestore(&sclp_tty_lock, flags);
+	return count;
+}
+
+static void
+sclp_ttybuf_callback(struct sclp_buffer *buffer, int rc)
+{
+	unsigned long flags;
+	void *page;
+
+	do {
+		page = sclp_unmake_buffer(buffer);
+		spin_lock_irqsave(&sclp_tty_lock, flags);
+		/* Remove buffer from outqueue */
+		list_del(&buffer->list);
+		sclp_tty_buffer_count--;
+		list_add_tail((struct list_head *) page, &sclp_tty_pages);
+		/* Check if there is a pending buffer on the out queue. */
+		buffer = NULL;
+		if (!list_empty(&sclp_tty_outqueue))
+			buffer = list_entry(sclp_tty_outqueue.next,
+					    struct sclp_buffer, list);
+		spin_unlock_irqrestore(&sclp_tty_lock, flags);
+	} while (buffer && sclp_emit_buffer(buffer, sclp_ttybuf_callback));
+	wake_up(&sclp_tty_waitq);
+	/* check if the tty needs a wake up call */
+	if (sclp_tty != NULL) {
+		tty_wakeup(sclp_tty);
+	}
+}
+
+static inline void
+__sclp_ttybuf_emit(struct sclp_buffer *buffer)
+{
+	unsigned long flags;
+	int count;
+	int rc;
+
+	spin_lock_irqsave(&sclp_tty_lock, flags);
+	list_add_tail(&buffer->list, &sclp_tty_outqueue);
+	count = sclp_tty_buffer_count++;
+	spin_unlock_irqrestore(&sclp_tty_lock, flags);
+	if (count)
+		return;
+	rc = sclp_emit_buffer(buffer, sclp_ttybuf_callback);
+	if (rc)
+		sclp_ttybuf_callback(buffer, rc);
+}
+
+/*
+ * When this routine is called from the timer then we flush the
+ * temporary write buffer.
+ */
+static void
+sclp_tty_timeout(unsigned long data)
+{
+	unsigned long flags;
+	struct sclp_buffer *buf;
+
+	spin_lock_irqsave(&sclp_tty_lock, flags);
+	buf = sclp_ttybuf;
+	sclp_ttybuf = NULL;
+	spin_unlock_irqrestore(&sclp_tty_lock, flags);
+
+	if (buf != NULL) {
+		__sclp_ttybuf_emit(buf);
+	}
+}
+
+/*
+ * Write a string to the sclp tty.
+ */
+static void
+sclp_tty_write_string(const unsigned char *str, int count)
+{
+	unsigned long flags;
+	void *page;
+	int written;
+	struct sclp_buffer *buf;
+
+	if (count <= 0)
+		return;
+	spin_lock_irqsave(&sclp_tty_lock, flags);
+	do {
+		/* Create a sclp output buffer if none exists yet */
+		if (sclp_ttybuf == NULL) {
+			while (list_empty(&sclp_tty_pages)) {
+				spin_unlock_irqrestore(&sclp_tty_lock, flags);
+				if (in_interrupt())
+					sclp_sync_wait();
+				else
+					wait_event(sclp_tty_waitq,
+						!list_empty(&sclp_tty_pages));
+				spin_lock_irqsave(&sclp_tty_lock, flags);
+			}
+			page = sclp_tty_pages.next;
+			list_del((struct list_head *) page);
+			sclp_ttybuf = sclp_make_buffer(page,
+						       sclp_ioctls.columns,
+						       sclp_ioctls.htab);
+		}
+		/* try to write the string to the current output buffer */
+		written = sclp_write(sclp_ttybuf, str, count);
+		if (written == count)
+			break;
+		/*
+		 * Not all characters could be written to the current
+		 * output buffer. Emit the buffer, create a new buffer
+		 * and then output the rest of the string.
+		 */
+		buf = sclp_ttybuf;
+		sclp_ttybuf = NULL;
+		spin_unlock_irqrestore(&sclp_tty_lock, flags);
+		__sclp_ttybuf_emit(buf);
+		spin_lock_irqsave(&sclp_tty_lock, flags);
+		str += written;
+		count -= written;
+	} while (count > 0);
+	/* Setup timer to output current console buffer after 1/10 second */
+	if (sclp_ioctls.final_nl) {
+		if (sclp_ttybuf != NULL &&
+		    sclp_chars_in_buffer(sclp_ttybuf) != 0 &&
+		    !timer_pending(&sclp_tty_timer)) {
+			init_timer(&sclp_tty_timer);
+			sclp_tty_timer.function = sclp_tty_timeout;
+			sclp_tty_timer.data = 0UL;
+			sclp_tty_timer.expires = jiffies + HZ/10;
+			add_timer(&sclp_tty_timer);
+		}
+	} else {
+		if (sclp_ttybuf != NULL &&
+		    sclp_chars_in_buffer(sclp_ttybuf) != 0) {
+			buf = sclp_ttybuf;
+			sclp_ttybuf = NULL;
+			spin_unlock_irqrestore(&sclp_tty_lock, flags);
+			__sclp_ttybuf_emit(buf);
+			spin_lock_irqsave(&sclp_tty_lock, flags);
+		}
+	}
+	spin_unlock_irqrestore(&sclp_tty_lock, flags);
+}
+
+/*
+ * This routine is called by the kernel to write a series of characters to the
+ * tty device. The characters may come from user space or kernel space. This
+ * routine will return the number of characters actually accepted for writing.
+ */
+static int
+sclp_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
+{
+	if (sclp_tty_chars_count > 0) {
+		sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+		sclp_tty_chars_count = 0;
+	}
+	sclp_tty_write_string(buf, count);
+	return count;
+}
+
+/*
+ * This routine is called by the kernel to write a single character to the tty
+ * device. If the kernel uses this routine, it must call the flush_chars()
+ * routine (if defined) when it is done stuffing characters into the driver.
+ *
+ * Characters provided to sclp_tty_put_char() are buffered by the SCLP driver.
+ * If the given character is a '\n' the contents of the SCLP write buffer
+ * - including previous characters from sclp_tty_put_char() and strings from
+ * sclp_write() without final '\n' - will be written.
+ */
+static void
+sclp_tty_put_char(struct tty_struct *tty, unsigned char ch)
+{
+	sclp_tty_chars[sclp_tty_chars_count++] = ch;
+	if (ch == '\n' || sclp_tty_chars_count >= SCLP_TTY_BUF_SIZE) {
+		sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+		sclp_tty_chars_count = 0;
+	}
+}
+
+/*
+ * This routine is called by the kernel after it has written a series of
+ * characters to the tty device using put_char().
+ */
+static void
+sclp_tty_flush_chars(struct tty_struct *tty)
+{
+	if (sclp_tty_chars_count > 0) {
+		sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+		sclp_tty_chars_count = 0;
+	}
+}
+
+/*
+ * This routine returns the number of characters in the write buffer of the
+ * SCLP driver. The provided number includes all characters that are stored
+ * in the SCCB (will be written next time the SCLP is not busy) as well as
+ * characters in the write buffer (will not be written as long as there is a
+ * final line feed missing).
+ */
+static int
+sclp_tty_chars_in_buffer(struct tty_struct *tty)
+{
+	unsigned long flags;
+	struct list_head *l;
+	struct sclp_buffer *t;
+	int count;
+
+	spin_lock_irqsave(&sclp_tty_lock, flags);
+	count = 0;
+	if (sclp_ttybuf != NULL)
+		count = sclp_chars_in_buffer(sclp_ttybuf);
+	list_for_each(l, &sclp_tty_outqueue) {
+		t = list_entry(l, struct sclp_buffer, list);
+		count += sclp_chars_in_buffer(t);
+	}
+	spin_unlock_irqrestore(&sclp_tty_lock, flags);
+	return count;
+}
+
+/*
+ * removes all content from buffers of low level driver
+ */
+static void
+sclp_tty_flush_buffer(struct tty_struct *tty)
+{
+	if (sclp_tty_chars_count > 0) {
+		sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
+		sclp_tty_chars_count = 0;
+	}
+}
+
+/*
+ * push input to tty
+ */
+static void
+sclp_tty_input(unsigned char* buf, unsigned int count)
+{
+	unsigned int cchar;
+
+	/*
+	 * If this tty driver is currently closed
+	 * then throw the received input away.
+	 */
+	if (sclp_tty == NULL)
+		return;
+	cchar = ctrlchar_handle(buf, count, sclp_tty);
+	switch (cchar & CTRLCHAR_MASK) {
+	case CTRLCHAR_SYSRQ:
+		break;
+	case CTRLCHAR_CTRL:
+		sclp_tty->flip.count++;
+		*sclp_tty->flip.flag_buf_ptr++ = TTY_NORMAL;
+		*sclp_tty->flip.char_buf_ptr++ = cchar;
+		tty_flip_buffer_push(sclp_tty);
+		break;
+	case CTRLCHAR_NONE:
+		/* send (normal) input to line discipline */
+		memcpy(sclp_tty->flip.char_buf_ptr, buf, count);
+		if (count < 2 ||
+		    (strncmp ((const char *) buf + count - 2, "^n", 2) &&
+		     strncmp ((const char *) buf + count - 2, "\0252n", 2))) {
+			sclp_tty->flip.char_buf_ptr[count] = '\n';
+			count++;
+		} else
+			count -= 2;
+		memset(sclp_tty->flip.flag_buf_ptr, TTY_NORMAL, count);
+		sclp_tty->flip.char_buf_ptr += count;
+		sclp_tty->flip.flag_buf_ptr += count;
+		sclp_tty->flip.count += count;
+		tty_flip_buffer_push(sclp_tty);
+		break;
+	}
+}
+
+/*
+ * get a EBCDIC string in upper/lower case,
+ * find out characters in lower/upper case separated by a special character,
+ * modifiy original string,
+ * returns length of resulting string
+ */
+static int
+sclp_switch_cases(unsigned char *buf, int count,
+		  unsigned char delim, int tolower)
+{
+	unsigned char *ip, *op;
+	int toggle;
+
+	/* initially changing case is off */
+	toggle = 0;
+	ip = op = buf;
+	while (count-- > 0) {
+		/* compare with special character */
+		if (*ip == delim) {
+			/* followed by another special character? */
+			if (count && ip[1] == delim) {
+				/*
+				 * ... then put a single copy of the special
+				 * character to the output string
+				 */
+				*op++ = *ip++;
+				count--;
+			} else
+				/*
+				 * ... special character follower by a normal
+				 * character toggles the case change behaviour
+				 */
+				toggle = ~toggle;
+			/* skip special character */
+			ip++;
+		} else
+			/* not the special character */
+			if (toggle)
+				/* but case switching is on */
+				if (tolower)
+					/* switch to uppercase */
+					*op++ = _ebc_toupper[(int) *ip++];
+				else
+					/* switch to lowercase */
+					*op++ = _ebc_tolower[(int) *ip++];
+			else
+				/* no case switching, copy the character */
+				*op++ = *ip++;
+	}
+	/* return length of reformatted string. */
+	return op - buf;
+}
+
+static void
+sclp_get_input(unsigned char *start, unsigned char *end)
+{
+	int count;
+
+	count = end - start;
+	/*
+	 * if set in ioctl convert EBCDIC to lower case
+	 * (modify original input in SCCB)
+	 */
+	if (sclp_ioctls.tolower)
+		EBC_TOLOWER(start, count);
+
+	/*
+	 * if set in ioctl find out characters in lower or upper case
+	 * (depends on current case) separated by a special character,
+	 * works on EBCDIC
+	 */
+	if (sclp_ioctls.delim)
+		count = sclp_switch_cases(start, count,
+					  sclp_ioctls.delim,
+					  sclp_ioctls.tolower);
+
+	/* convert EBCDIC to ASCII (modify original input in SCCB) */
+	sclp_ebcasc_str(start, count);
+
+	/* if set in ioctl write operators input to console  */
+	if (sclp_ioctls.echo)
+		sclp_tty_write(sclp_tty, start, count);
+
+	/* transfer input to high level driver */
+	sclp_tty_input(start, count);
+}
+
+static inline struct gds_vector *
+find_gds_vector(struct gds_vector *start, struct gds_vector *end, u16 id)
+{
+	struct gds_vector *vec;
+
+	for (vec = start; vec < end; vec = (void *) vec + vec->length)
+		if (vec->gds_id == id)
+			return vec;
+	return NULL;
+}
+
+static inline struct gds_subvector *
+find_gds_subvector(struct gds_subvector *start,
+		   struct gds_subvector *end, u8 key)
+{
+	struct gds_subvector *subvec;
+
+	for (subvec = start; subvec < end;
+	     subvec = (void *) subvec + subvec->length)
+		if (subvec->key == key)
+			return subvec;
+	return NULL;
+}
+
+static inline void
+sclp_eval_selfdeftextmsg(struct gds_subvector *start,
+			 struct gds_subvector *end)
+{
+	struct gds_subvector *subvec;
+
+	subvec = start;
+	while (subvec < end) {
+		subvec = find_gds_subvector(subvec, end, 0x30);
+		if (!subvec)
+			break;
+		sclp_get_input((unsigned char *)(subvec + 1),
+			       (unsigned char *) subvec + subvec->length);
+		subvec = (void *) subvec + subvec->length;
+	}
+}
+
+static inline void
+sclp_eval_textcmd(struct gds_subvector *start,
+		  struct gds_subvector *end)
+{
+	struct gds_subvector *subvec;
+
+	subvec = start;
+	while (subvec < end) {
+		subvec = find_gds_subvector(subvec, end,
+					    GDS_KEY_SelfDefTextMsg);
+		if (!subvec)
+			break;
+		sclp_eval_selfdeftextmsg((struct gds_subvector *)(subvec + 1),
+					 (void *)subvec + subvec->length);
+		subvec = (void *) subvec + subvec->length;
+	}
+}
+
+static inline void
+sclp_eval_cpmsu(struct gds_vector *start, struct gds_vector *end)
+{
+	struct gds_vector *vec;
+
+	vec = start;
+	while (vec < end) {
+		vec = find_gds_vector(vec, end, GDS_ID_TextCmd);
+		if (!vec)
+			break;
+		sclp_eval_textcmd((struct gds_subvector *)(vec + 1),
+				  (void *) vec + vec->length);
+		vec = (void *) vec + vec->length;
+	}
+}
+
+
+static inline void
+sclp_eval_mdsmu(struct gds_vector *start, void *end)
+{
+	struct gds_vector *vec;
+
+	vec = find_gds_vector(start, end, GDS_ID_CPMSU);
+	if (vec)
+		sclp_eval_cpmsu(vec + 1, (void *) vec + vec->length);
+}
+
+static void
+sclp_tty_receiver(struct evbuf_header *evbuf)
+{
+	struct gds_vector *start, *end, *vec;
+
+	start = (struct gds_vector *)(evbuf + 1);
+	end = (void *) evbuf + evbuf->length;
+	vec = find_gds_vector(start, end, GDS_ID_MDSMU);
+	if (vec)
+		sclp_eval_mdsmu(vec + 1, (void *) vec + vec->length);
+}
+
+static void
+sclp_tty_state_change(struct sclp_register *reg)
+{
+}
+
+static struct sclp_register sclp_input_event =
+{
+	.receive_mask = EvTyp_OpCmd_Mask | EvTyp_PMsgCmd_Mask,
+	.state_change_fn = sclp_tty_state_change,
+	.receiver_fn = sclp_tty_receiver
+};
+
+static struct tty_operations sclp_ops = {
+	.open = sclp_tty_open,
+	.close = sclp_tty_close,
+	.write = sclp_tty_write,
+	.put_char = sclp_tty_put_char,
+	.flush_chars = sclp_tty_flush_chars,
+	.write_room = sclp_tty_write_room,
+	.chars_in_buffer = sclp_tty_chars_in_buffer,
+	.flush_buffer = sclp_tty_flush_buffer,
+	.ioctl = sclp_tty_ioctl,
+};
+
+int __init
+sclp_tty_init(void)
+{
+	struct tty_driver *driver;
+	void *page;
+	int i;
+	int rc;
+
+	if (!CONSOLE_IS_SCLP)
+		return 0;
+	driver = alloc_tty_driver(1);
+	if (!driver)
+		return -ENOMEM;
+
+	rc = sclp_rw_init();
+	if (rc) {
+		printk(KERN_ERR SCLP_TTY_PRINT_HEADER
+		       "could not register tty - "
+		       "sclp_rw_init returned %d\n", rc);
+		put_tty_driver(driver);
+		return rc;
+	}
+	/* Allocate pages for output buffering */
+	INIT_LIST_HEAD(&sclp_tty_pages);
+	for (i = 0; i < MAX_KMEM_PAGES; i++) {
+		page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+		if (page == NULL) {
+			put_tty_driver(driver);
+			return -ENOMEM;
+		}
+		list_add_tail((struct list_head *) page, &sclp_tty_pages);
+	}
+	INIT_LIST_HEAD(&sclp_tty_outqueue);
+	spin_lock_init(&sclp_tty_lock);
+	init_waitqueue_head(&sclp_tty_waitq);
+	init_timer(&sclp_tty_timer);
+	sclp_ttybuf = NULL;
+	sclp_tty_buffer_count = 0;
+	if (MACHINE_IS_VM) {
+		/*
+		 * save 4 characters for the CPU number
+		 * written at start of each line by VM/CP
+		 */
+		sclp_ioctls_init.columns = 76;
+		/* case input lines to lowercase */
+		sclp_ioctls_init.tolower = 1;
+	}
+	sclp_ioctls = sclp_ioctls_init;
+	sclp_tty_chars_count = 0;
+	sclp_tty = NULL;
+
+	rc = sclp_register(&sclp_input_event);
+	if (rc) {
+		put_tty_driver(driver);
+		return rc;
+	}
+
+	driver->owner = THIS_MODULE;
+	driver->driver_name = "sclp_line";
+	driver->name = "sclp_line";
+	driver->major = TTY_MAJOR;
+	driver->minor_start = 64;
+	driver->type = TTY_DRIVER_TYPE_SYSTEM;
+	driver->subtype = SYSTEM_TYPE_TTY;
+	driver->init_termios = tty_std_termios;
+	driver->init_termios.c_iflag = IGNBRK | IGNPAR;
+	driver->init_termios.c_oflag = ONLCR | XTABS;
+	driver->init_termios.c_lflag = ISIG | ECHO;
+	driver->flags = TTY_DRIVER_REAL_RAW;
+	tty_set_operations(driver, &sclp_ops);
+	rc = tty_register_driver(driver);
+	if (rc) {
+		printk(KERN_ERR SCLP_TTY_PRINT_HEADER
+		       "could not register tty - "
+		       "tty_register_driver returned %d\n", rc);
+		put_tty_driver(driver);
+		return rc;
+	}
+	sclp_tty_driver = driver;
+	return 0;
+}
+module_init(sclp_tty_init);