[PATCH] s390: sclp driver part 2.

Reworked sclp driver part 2.

drivers/s390/char/sclp.h

+/*
+ *  drivers/s390/char/sclp.h
+ *
+ *  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>
+ */
+
+#ifndef __SCLP_H__
+#define __SCLP_H__
+
+#include <linux/types.h>
+#include <linux/list.h>
+
+#include <asm/ebcdic.h>
+
+/* maximum number of pages concerning our own memory management */
+#define MAX_KMEM_PAGES (sizeof(unsigned long) << 3)
+#define MAX_CONSOLE_PAGES	4
+
+#define EvTyp_OpCmd		0x01
+#define EvTyp_Msg		0x02
+#define EvTyp_StateChange	0x08
+#define EvTyp_PMsgCmd		0x09
+#define EvTyp_CntlProgOpCmd	0x20
+#define EvTyp_CntlProgIdent	0x0B
+#define EvTyp_SigQuiesce	0x1D
+
+#define EvTyp_OpCmd_Mask	0x80000000
+#define EvTyp_Msg_Mask		0x40000000
+#define EvTyp_StateChange_Mask	0x01000000
+#define EvTyp_PMsgCmd_Mask	0x00800000
+#define EvTyp_CtlProgOpCmd_Mask	0x00000001
+#define EvTyp_CtlProgIdent_Mask	0x00200000
+#define EvTyp_SigQuiesce_Mask	0x00000008
+
+#define GnrlMsgFlgs_DOM		0x8000
+#define GnrlMsgFlgs_SndAlrm	0x4000
+#define GnrlMsgFlgs_HoldMsg	0x2000
+
+#define LnTpFlgs_CntlText	0x8000
+#define LnTpFlgs_LabelText	0x4000
+#define LnTpFlgs_DataText	0x2000
+#define LnTpFlgs_EndText	0x1000
+#define LnTpFlgs_PromptText	0x0800
+
+#define SCLP_COMMAND_INITIATED	0
+#define SCLP_BUSY		2
+#define SCLP_NOT_OPERATIONAL	3
+
+typedef unsigned int sclp_cmdw_t;
+
+#define SCLP_CMDW_READDATA	0x00770005
+#define SCLP_CMDW_WRITEDATA	0x00760005
+#define SCLP_CMDW_WRITEMASK	0x00780005
+
+#define GDS_ID_MDSMU		0x1310
+#define GDS_ID_MDSRouteInfo	0x1311
+#define GDS_ID_AgUnWrkCorr	0x1549
+#define GDS_ID_SNACondReport	0x1532
+#define GDS_ID_CPMSU		0x1212
+#define GDS_ID_RoutTargInstr	0x154D
+#define GDS_ID_OpReq		0x8070
+#define GDS_ID_TextCmd		0x1320
+
+#define GDS_KEY_SelfDefTextMsg	0x31
+
+typedef u32 sccb_mask_t;	/* ATTENTION: assumes 32bit mask !!! */
+
+struct sccb_header {
+	u16	length;
+	u8	function_code;
+	u8	control_mask[3];
+	u16	response_code;
+} __attribute__((packed));
+
+struct gds_subvector {
+	u8	length;
+	u8	key;
+} __attribute__((packed));
+
+struct gds_vector {
+	u16	length;
+	u16	gds_id;
+} __attribute__((packed));
+
+struct evbuf_header {
+	u16	length;
+	u8	type;
+	u8	flags;
+	u16	_reserved;
+} __attribute__((packed));
+
+struct sclp_req {
+	struct list_head list;		/* list_head for request queueing. */
+	sclp_cmdw_t command;		/* sclp command to execute */
+	void	*sccb;			/* pointer to the sccb to execute */
+	char	status;			/* status of this request */
+	/* Callback that is called after reaching final status. */
+	void (*callback)(struct sclp_req *, void *data);
+	void *callback_data;
+};
+
+#define SCLP_REQ_FILLED	  0x00	/* request is ready to be processed */
+#define SCLP_REQ_QUEUED	  0x01	/* request is queued to be processed */
+#define SCLP_REQ_RUNNING  0x02	/* request is currently running */
+#define SCLP_REQ_DONE	  0x03	/* request is completed successfully */
+#define SCLP_REQ_FAILED	  0x05	/* request is finally failed */
+
+/* function pointers that a high level driver has to use for registration */
+/* of some routines it wants to be called from the low level driver */
+struct sclp_register {
+	struct list_head list;
+	/* event masks this user is registered for */
+	sccb_mask_t receive_mask;
+	sccb_mask_t send_mask;
+	/* actually present events */
+	sccb_mask_t sclp_receive_mask;
+	sccb_mask_t sclp_send_mask;
+	/* called if event type availability changes */
+	void (*state_change_fn)(struct sclp_register *);
+	/* called for events in cp_receive_mask/sclp_receive_mask */
+	void (*receiver_fn)(struct evbuf_header *);
+};
+
+/* externals from sclp.c */
+void sclp_add_request(struct sclp_req *req);
+void sclp_sync_wait(void);
+int sclp_register(struct sclp_register *reg);
+void sclp_unregister(struct sclp_register *reg);
+
+/* useful inlines */
+
+/* VM uses EBCDIC 037, LPAR+native(SE+HMC) use EBCDIC 500 */
+/* translate single character from ASCII to EBCDIC */
+static inline unsigned char
+sclp_ascebc(unsigned char ch)
+{
+	return (MACHINE_IS_VM) ? _ascebc[ch] : _ascebc_500[ch];
+}
+
+/* translate string from EBCDIC to ASCII */
+static inline void
+sclp_ebcasc_str(unsigned char *str, int nr)
+{
+	(MACHINE_IS_VM) ? EBCASC(str, nr) : EBCASC_500(str, nr);
+}
+
+/* translate string from ASCII to EBCDIC */
+static inline void
+sclp_ascebc_str(unsigned char *str, int nr)
+{
+	(MACHINE_IS_VM) ? ASCEBC(str, nr) : ASCEBC_500(str, nr);
+}
+
+#endif	 /* __SCLP_H__ */

drivers/s390/char/sclp_con.c

+/*
+ *  drivers/s390/char/sclp_con.c
+ *    SCLP line mode console 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/version.h>
+#include <linux/kmod.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+#include <linux/bootmem.h>
+
+#include "sclp.h"
+#include "sclp_rw.h"
+
+#define SCLP_CON_PRINT_HEADER "sclp console driver: "
+
+#define sclp_console_major 4		/* TTYAUX_MAJOR */
+#define sclp_console_minor 64
+#define sclp_console_name  "console"
+
+/* Lock to guard over changes to global variables */
+static spinlock_t sclp_con_lock;
+/* List of free pages that can be used for console output buffering */
+static struct list_head sclp_con_pages;
+/* List of full struct sclp_buffer structures ready for output */
+static struct list_head sclp_con_outqueue;
+/* Counter how many buffers are emitted (max 1) and how many */
+/* are on the output queue. */
+static int sclp_con_buffer_count;
+/* Pointer to current console buffer */
+static struct sclp_buffer *sclp_conbuf;
+/* Timer for delayed output of console messages */
+static struct timer_list sclp_con_timer;
+
+/* Output format for console messages */
+static unsigned short sclp_con_columns;
+static unsigned short sclp_con_width_htab;
+
+static void
+sclp_conbuf_callback(struct sclp_buffer *buffer, int rc)
+{
+	unsigned long flags;
+	struct sclp_buffer *next;
+	void *page;
+
+	/* FIXME: what if rc != 0x0020 */
+	page = sclp_unmake_buffer(buffer);
+	spin_lock_irqsave(&sclp_con_lock, flags);
+	list_add_tail((struct list_head *) page, &sclp_con_pages);
+	sclp_con_buffer_count--;
+	/* Remove buffer from outqueue */
+	list_del(&buffer->list);
+	/* Check if there is a pending buffer on the out queue. */
+	next = NULL;
+	if (!list_empty(&sclp_con_outqueue))
+		next = list_entry(sclp_con_outqueue.next,
+				  struct sclp_buffer, list);
+	spin_unlock_irqrestore(&sclp_con_lock, flags);
+	if (next != NULL)
+		sclp_emit_buffer(next, sclp_conbuf_callback);
+}
+
+static inline void
+__sclp_conbuf_emit(struct sclp_buffer *buffer)
+{
+	list_add_tail(&buffer->list, &sclp_con_outqueue);
+	if (sclp_con_buffer_count++ == 0)
+		sclp_emit_buffer(buffer, sclp_conbuf_callback);
+}
+
+/*
+ * When this routine is called from the timer then we flush the
+ * temporary write buffer without further waiting on a final new line.
+ */
+static void
+sclp_console_timeout(unsigned long data)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sclp_con_lock, flags);
+	if (sclp_conbuf != NULL) {
+		__sclp_conbuf_emit(sclp_conbuf);
+		sclp_conbuf = NULL;
+	}
+	spin_unlock_irqrestore(&sclp_con_lock, flags);
+}
+
+/*
+ * Writes the given message to S390 system console
+ */
+void
+sclp_console_write(struct console *console, const char *message,
+		   unsigned int count)
+{
+	unsigned long flags;
+	void *page;
+	int written;
+
+	if (count <= 0)
+		return;
+	spin_lock_irqsave(&sclp_con_lock, flags);
+	/*
+	 * process escape characters, write message into buffer,
+	 * send buffer to SCLP
+	 */
+	do {
+		/* make sure we have a console output buffer */
+		if (sclp_conbuf == NULL) {
+			while (list_empty(&sclp_con_pages)) {
+				spin_unlock_irqrestore(&sclp_con_lock, flags);
+				sclp_sync_wait();
+				spin_lock_irqsave(&sclp_con_lock, flags);
+			}
+			page = sclp_con_pages.next;
+			list_del((struct list_head *) page);
+			sclp_conbuf = sclp_make_buffer(page, sclp_con_columns,
+						       sclp_con_width_htab);
+		}
+		/* try to write the string to the current output buffer */
+		written = sclp_write(sclp_conbuf, message, count, 0);
+		if (written == -EFAULT || 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.
+		 */
+		__sclp_conbuf_emit(sclp_conbuf);
+		sclp_conbuf = NULL;
+		message += written;
+		count -= written;
+	} while (count > 0);
+	/* Setup timer to output current console buffer after 1/10 second */
+	if (sclp_conbuf != NULL && !timer_pending(&sclp_con_timer)) {
+		init_timer(&sclp_con_timer);
+		sclp_con_timer.function = sclp_console_timeout;
+		sclp_con_timer.data = 0UL;
+		sclp_con_timer.expires = jiffies + HZ/10;
+		add_timer(&sclp_con_timer);
+	}
+	spin_unlock_irqrestore(&sclp_con_lock, flags);
+}
+
+/* returns the device number of the SCLP console */
+kdev_t
+sclp_console_device(struct console *c)
+{
+	return	mk_kdev(sclp_console_major, sclp_console_minor);
+}
+
+/*
+ * This routine is called from panic when the kernel
+ * is going to give up. We have to make sure that all buffers
+ * will be flushed to the SCLP.
+ */
+void
+sclp_console_unblank(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sclp_con_lock, flags);
+	if (timer_pending(&sclp_con_timer))
+		del_timer(&sclp_con_timer);
+	if (sclp_conbuf != NULL) {
+		__sclp_conbuf_emit(sclp_conbuf);
+		sclp_conbuf = NULL;
+	}
+	while (sclp_con_buffer_count > 0) {
+		spin_unlock_irqrestore(&sclp_con_lock, flags);
+		sclp_sync_wait();
+		spin_lock_irqsave(&sclp_con_lock, flags);
+	}
+	spin_unlock_irqrestore(&sclp_con_lock, flags);
+}
+
+/*
+ * used to register the SCLP console to the kernel and to
+ * give printk necessary information
+ */
+struct console sclp_console =
+{
+	.name = sclp_console_name,
+	.write = sclp_console_write,
+	.device = sclp_console_device,
+	.unblank = sclp_console_unblank,
+	.flags = CON_PRINTBUFFER
+};
+
+/*
+ * called by console_init() in drivers/char/tty_io.c at boot-time.
+ */
+void __init
+sclp_console_init(void)
+{
+	void *page;
+	int i;
+
+	if (!CONSOLE_IS_SCLP)
+		return;
+	if (sclp_rw_init() != 0)
+		return;
+	/* Allocate pages for output buffering */
+	INIT_LIST_HEAD(&sclp_con_pages);
+	for (i = 0; i < MAX_CONSOLE_PAGES; i++) {
+		page = alloc_bootmem_low_pages(PAGE_SIZE);
+		if (page == NULL)
+			return;
+		list_add_tail((struct list_head *) page, &sclp_con_pages);
+	}
+	INIT_LIST_HEAD(&sclp_con_outqueue);
+	spin_lock_init(&sclp_con_lock);
+	sclp_con_buffer_count = 0;
+	sclp_conbuf = NULL;
+	init_timer(&sclp_con_timer);
+
+	/* Set output format */
+	if (MACHINE_IS_VM)
+		/*
+		 * save 4 characters for the CPU number
+		 * written at start of each line by VM/CP
+		 */
+		sclp_con_columns = 76;
+	else
+		sclp_con_columns = 80;
+	sclp_con_width_htab = 8;
+
+	/* enable printks access to this driver */
+	register_console(&sclp_console);
+}

drivers/s390/char/sclp_cpi.c

+/*
+ * Author: Martin Peschke <mpeschke@de.ibm.com>
+ * Copyright (C) 2001 IBM Entwicklung GmbH, IBM Corporation
+ *
+ * SCLP Control-Program Identification.
+ */
+
+#include <linux/config.h>
+#include <linux/version.h>
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <asm/ebcdic.h>
+#include <asm/semaphore.h>
+
+#include "sclp.h"
+#include "sclp_rw.h"
+
+#define CPI_LENGTH_SYSTEM_TYPE	8
+#define CPI_LENGTH_SYSTEM_NAME	8
+#define CPI_LENGTH_SYSPLEX_NAME	8
+
+struct cpi_evbuf {
+	struct evbuf_header header;
+	u8	id_format;
+	u8	reserved0;
+	u8	system_type[CPI_LENGTH_SYSTEM_TYPE];
+	u64	reserved1;
+	u8	system_name[CPI_LENGTH_SYSTEM_NAME];
+	u64	reserved2;
+	u64	system_level;
+	u64	reserved3;
+	u8	sysplex_name[CPI_LENGTH_SYSPLEX_NAME];
+	u8	reserved4[16];
+} __attribute__((packed));
+
+struct cpi_sccb {
+	struct sccb_header header;
+	struct cpi_evbuf cpi_evbuf;
+} __attribute__((packed));
+
+/* Event type structure for write message and write priority message */
+static struct sclp_register sclp_cpi_event =
+{
+	.send_mask = EvTyp_CtlProgIdent_Mask
+};
+
+MODULE_AUTHOR(
+	"Martin Peschke, IBM Deutschland Entwicklung GmbH "
+	"<mpeschke@de.ibm.com>");
+
+MODULE_DESCRIPTION(
+	"identify this operating system instance to the S/390 "
+	"or zSeries hardware");
+
+static char *system_name = NULL;
+MODULE_PARM(system_name, "s");
+MODULE_PARM_DESC(system_name, "e.g. hostname - max. 8 characters");
+
+static char *sysplex_name = NULL;
+#ifdef ALLOW_SYSPLEX_NAME
+MODULE_PARM(sysplex_name, "s");
+MODULE_PARM_DESC(sysplex_name, "if applicable - max. 8 characters");
+#endif
+
+/* use default value for this field (as well as for system level) */
+static char *system_type = "LINUX";
+
+static int
+cpi_check_parms(void)
+{
+	/* reject if no system type specified */
+	if (!system_type) {
+		printk("cpi: bug: no system type specified\n");
+		return -EINVAL;
+	}
+
+	/* reject if system type larger than 8 characters */
+	if (strlen(system_type) > CPI_LENGTH_SYSTEM_NAME) {
+		printk("cpi: bug: system type has length of %li characters - "
+		       "only %i characters supported\n",
+		       strlen(system_type), CPI_LENGTH_SYSTEM_TYPE);
+		return -EINVAL;
+	}
+
+	/* reject if no system name specified */
+	if (!system_name) {
+		printk("cpi: no system name specified\n");
+		return -EINVAL;
+	}
+
+	/* reject if system name larger than 8 characters */
+	if (strlen(system_name) > CPI_LENGTH_SYSTEM_NAME) {
+		printk("cpi: system name has length of %li characters - "
+		       "only %i characters supported\n",
+		       strlen(system_name), CPI_LENGTH_SYSTEM_NAME);
+		return -EINVAL;
+	}
+
+	/* reject if specified sysplex name larger than 8 characters */
+	if (sysplex_name && strlen(sysplex_name) > CPI_LENGTH_SYSPLEX_NAME) {
+		printk("cpi: sysplex name has length of %li characters"
+		       " - only %i characters supported\n",
+		       strlen(sysplex_name), CPI_LENGTH_SYSPLEX_NAME);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static void
+cpi_callback(struct sclp_req *req, void *data)
+{
+	struct semaphore *sem;
+
+	sem = (struct semaphore *) data;
+	up(sem);
+}
+
+static struct sclp_req *
+cpi_prepare_req(void)
+{
+	struct sclp_req *req;
+	struct cpi_sccb *sccb;
+	struct cpi_evbuf *evb;
+
+	req = (struct sclp_req *) kmalloc(sizeof(struct sclp_req), GFP_KERNEL);
+	if (req == NULL)
+		return ERR_PTR(-ENOMEM);
+	sccb = (struct cpi_sccb *) get_free_page(GFP_KERNEL);
+	if (sccb == NULL) {
+		kfree(req);
+		return ERR_PTR(-ENOMEM);
+	}
+	memset(sccb, 0, sizeof(struct cpi_sccb));
+
+	/* setup SCCB for Control-Program Identification */
+	sccb->header.length = sizeof(struct cpi_sccb);
+	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
+	sccb->cpi_evbuf.header.type = 0x0B;
+	evb = &sccb->cpi_evbuf;
+
+	/* set system type */
+	memset(evb->system_type, ' ', CPI_LENGTH_SYSTEM_TYPE);
+	memcpy(evb->system_type, system_type, strlen(system_type));
+	sclp_ascebc_str(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
+	EBC_TOUPPER(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
+
+	/* set system name */
+	memset(evb->system_name, ' ', CPI_LENGTH_SYSTEM_NAME);
+	memcpy(evb->system_name, system_name, strlen(system_name));
+	sclp_ascebc_str(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
+	EBC_TOUPPER(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
+
+	/* set sytem level */
+	evb->system_level = LINUX_VERSION_CODE;
+
+	/* set sysplex name */
+	if (sysplex_name) {
+		memset(evb->sysplex_name, ' ', CPI_LENGTH_SYSPLEX_NAME);
+		memcpy(evb->sysplex_name, sysplex_name, strlen(sysplex_name));
+		sclp_ascebc_str(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
+		EBC_TOUPPER(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
+	}
+
+	/* prepare request data structure presented to SCLP driver */
+	req->command = SCLP_CMDW_WRITEDATA;
+	req->sccb = sccb;
+	req->status = SCLP_REQ_FILLED;
+	req->callback = cpi_callback;
+	return req;
+}
+
+static void
+cpi_free_req(struct sclp_req *req)
+{
+	free_page((unsigned long) req->sccb);
+	kfree(req);
+}
+
+static int __init
+cpi_module_init(void)
+{
+	struct semaphore sem;
+	struct sclp_req *req;
+	int rc;
+
+	rc = cpi_check_parms();
+	if (rc)
+		return rc;
+
+	rc = sclp_register(&sclp_cpi_event);
+	if (rc) {
+		/* could not register sclp event. Die. */
+		printk("cpi: could not register to hardware console.\n");
+		return -EINVAL;
+	}
+	if (!(sclp_cpi_event.sclp_send_mask & EvTyp_CtlProgIdent_Mask)) {
+		printk("cpi: no control program identification support\n");
+		sclp_unregister(&sclp_cpi_event);
+		return -ENOTSUPP;
+	}
+
+	req = cpi_prepare_req();
+	if (IS_ERR(req)) {
+		printk("cpi: couldn't allocate request\n");
+		sclp_unregister(&sclp_cpi_event);
+		return PTR_ERR(req);
+	}
+
+	/* Prepare semaphore */
+	sema_init(&sem, 0);
+	req->callback_data = &sem;
+	/* Add request to sclp queue */
+	sclp_add_request(req);
+	/* make "insmod" sleep until callback arrives */
+	down(&sem);
+
+	rc = ((struct cpi_sccb *) req->sccb)->header.response_code;
+	if (rc != 0x0020) {
+		printk("cpi: failed with response code 0x%x\n", rc);
+		rc = -ECOMM;
+	} else
+		rc = 0;
+
+	cpi_free_req(req);
+
+	return rc;
+}
+
+
+static void __exit cpi_module_exit(void)
+{
+}
+
+
+/* declare driver module init/cleanup functions */
+module_init(cpi_module_init);
+module_exit(cpi_module_exit);
+

drivers/s390/char/sclp_rw.h

+/*
+ *  drivers/s390/char/sclp_rw.h
+ *    interface to the SCLP-read/write 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>
+ */
+
+#ifndef __SCLP_RW_H__
+#define __SCLP_RW_H__
+
+struct mto {
+	u16 length;
+	u16 type;
+	u16 line_type_flags;
+	u8  alarm_control;
+	u8  _reserved[3];
+} __attribute__((packed));
+
+struct go {
+	u16 length;
+	u16 type;
+	u32 domid;
+	u8  hhmmss_time[8];
+	u8  th_time[3];
+	u8  reserved_0;
+	u8  dddyyyy_date[7];
+	u8  _reserved_1;
+	u16 general_msg_flags;
+	u8  _reserved_2[10];
+	u8  originating_system_name[8];
+	u8  job_guest_name[8];
+} __attribute__((packed));
+
+struct mdb_header {
+	u16 length;
+	u16 type;
+	u32 tag;
+	u32 revision_code;
+} __attribute__((packed));
+
+struct mdb {
+	struct mdb_header header;
+	struct go go;
+} __attribute__((packed));
+
+struct msg_buf {
+	struct evbuf_header header;
+	struct mdb mdb;
+} __attribute__((packed));
+
+struct write_sccb {
+	struct sccb_header header;
+	struct msg_buf msg_buf;
+} __attribute__((packed));
+
+/* The number of empty mto buffers that can be contained in a single sccb. */
+#define NR_EMPTY_MTO_PER_SCCB ((PAGE_SIZE - sizeof(struct sclp_buffer) - \
+			sizeof(struct write_sccb)) / sizeof(struct mto))
+
+/*
+ * data structure for information about list of SCCBs (only for writing),
+ * will be located at the end of a SCCBs page
+ */
+struct sclp_buffer {
+	struct list_head list;		/* list_head for sccb_info chain */
+	struct sclp_req request;
+	struct write_sccb *sccb;
+	char *current_line;
+	int current_length;
+	/* output format settings */
+	unsigned short columns;
+	unsigned short htab;
+	/* statistics about this buffer */
+	unsigned int mto_char_sum;	/* # chars in sccb */
+	unsigned int mto_number;	/* # mtos in sccb */
+	/* Callback that is called after reaching final status. */
+	void (*callback)(struct sclp_buffer *, int);
+};
+
+int sclp_rw_init(void);
+struct sclp_buffer *sclp_make_buffer(void *, unsigned short, unsigned short);
+void *sclp_unmake_buffer(struct sclp_buffer *);
+int sclp_buffer_space(struct sclp_buffer *);
+int sclp_write(struct sclp_buffer *buffer, const char *, int, int);
+void sclp_move_current_line(struct sclp_buffer *, struct sclp_buffer *);
+void sclp_emit_buffer(struct sclp_buffer *,void (*)(struct sclp_buffer *,int));
+void sclp_set_columns(struct sclp_buffer *, unsigned short);
+void sclp_set_htab(struct sclp_buffer *, unsigned short);
+int sclp_chars_in_buffer(struct sclp_buffer *);
+
+#endif	/* __SCLP_RW_H__ */

drivers/s390/char/sclp_tty.h

+/*
+ *  drivers/s390/char/sclp_tty.h
+ *    interface to the SCLP-read/write 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>
+ */
+
+#ifndef __SCLP_TTY_H__
+#define __SCLP_TTY_H__
+
+#include <linux/ioctl.h>
+
+/* This is the type of data structures storing sclp ioctl setting. */
+struct sclp_ioctls {
+	unsigned short htab;
+	unsigned char echo;
+	unsigned short columns;
+	signed char final_nl;
+	unsigned short max_sccb;
+	unsigned short kmem_sccb;	/* cant be modified at run time */
+	unsigned char tolower;
+	unsigned char delim;
+};
+
+/* must be unique, FIXME: must be added in Documentation/ioctl_number.txt */
+#define SCLP_IOCTL_LETTER 'B'
+
+/* set width of horizontal tabulator */
+#define TIOCSCLPSHTAB	_IOW(SCLP_IOCTL_LETTER, 0, unsigned short)
+/* enable/disable echo of input (independent from line discipline) */
+#define TIOCSCLPSECHO	_IOW(SCLP_IOCTL_LETTER, 1, unsigned char)
+/* set number of colums for output */
+#define TIOCSCLPSCOLS	_IOW(SCLP_IOCTL_LETTER, 2, unsigned short)
+/* enable/disable writing without final new line character */
+#define TIOCSCLPSNL	_IOW(SCLP_IOCTL_LETTER, 4, signed char)
+/* set the maximum buffers size for output, rounded up to next 4kB boundary */
+#define TIOCSCLPSOBUF	_IOW(SCLP_IOCTL_LETTER, 5, unsigned short)
+/* set initial (default) sclp ioctls */
+#define TIOCSCLPSINIT	_IO(SCLP_IOCTL_LETTER, 6)
+/* enable/disable conversion from upper to lower case of input */
+#define TIOCSCLPSCASE	_IOW(SCLP_IOCTL_LETTER, 7, unsigned char)
+/* set special character used for seperating upper and lower case, */
+/* 0x00 disables this feature */
+#define TIOCSCLPSDELIM	_IOW(SCLP_IOCTL_LETTER, 9, unsigned char)
+
+/* get width of horizontal tabulator */
+#define TIOCSCLPGHTAB	_IOR(SCLP_IOCTL_LETTER, 10, unsigned short)
+/* Is echo of input enabled ? (independent from line discipline) */
+#define TIOCSCLPGECHO	_IOR(SCLP_IOCTL_LETTER, 11, unsigned char)
+/* get number of colums for output */
+#define TIOCSCLPGCOLS	_IOR(SCLP_IOCTL_LETTER, 12, unsigned short)
+/* Is writing without final new line character enabled ? */
+#define TIOCSCLPGNL	_IOR(SCLP_IOCTL_LETTER, 14, signed char)
+/* get the maximum buffers size for output */
+#define TIOCSCLPGOBUF	_IOR(SCLP_IOCTL_LETTER, 15, unsigned short)
+/* Is conversion from upper to lower case of input enabled ? */
+#define TIOCSCLPGCASE	_IOR(SCLP_IOCTL_LETTER, 17, unsigned char)
+/* get special character used for seperating upper and lower case, */
+/* 0x00 disables this feature */
+#define TIOCSCLPGDELIM	_IOR(SCLP_IOCTL_LETTER, 19, unsigned char)
+/* get the number of buffers/pages got from kernel at startup */
+#define TIOCSCLPGKBUF	_IOR(SCLP_IOCTL_LETTER, 20, unsigned short)
+
+#endif	/* __SCLP_TTY_H__ */