[PATCH] s390: introduce struct subchannel_id

This patch introduces a struct subchannel_id containing the subchannel number
(formerly referred to as "irq") and switches code formerly relying on the
subchannel number over to it.

While we're touching inline assemblies anyway, make sure they have correct
memory constraints.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

18 files changed, 313 insertions, 238 deletions

diff --git a/drivers/s390/cio/blacklist.c b/drivers/s390/cio/blacklist.c
index a1c52a68219..a4b03031ff5 100644
--- a/drivers/s390/cio/blacklist.c
+++ b/drivers/s390/cio/blacklist.c
@@ -35,7 +35,7 @@
  */
 
 /* 65536 bits to indicate if a devno is blacklisted or not */
-#define __BL_DEV_WORDS ((__MAX_SUBCHANNELS + (8*sizeof(long) - 1)) / \
+#define __BL_DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
 			 (8*sizeof(long)))
 static unsigned long bl_dev[__BL_DEV_WORDS];
 typedef enum {add, free} range_action;
@@ -50,7 +50,7 @@ blacklist_range (range_action action, unsigned int from, unsigned int to)
 	if (!to)
 		to = from;
 
-	if (from > to || to > __MAX_SUBCHANNELS) {
+	if (from > to || to > __MAX_SUBCHANNEL) {
 		printk (KERN_WARNING "Invalid blacklist range "
 			"0x%04x to 0x%04x, skipping\n", from, to);
 		return;
@@ -143,7 +143,7 @@ blacklist_parse_parameters (char *str, range_action action)
 		if (strncmp(str,"all,",4) == 0 || strcmp(str,"all") == 0 ||
 		    strncmp(str,"all\n",4) == 0 || strncmp(str,"all ",4) == 0) {
 			from = 0;
-			to = __MAX_SUBCHANNELS;
+			to = __MAX_SUBCHANNEL;
 			str += 3;
 		} else {
 			int rc;
@@ -226,20 +226,21 @@ is_blacklisted (int devno)
 static inline void
 s390_redo_validation (void)
 {
-	unsigned int irq;
+	struct subchannel_id schid;
 
 	CIO_TRACE_EVENT (0, "redoval");
-	for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+	init_subchannel_id(&schid);
+	do {
 		int ret;
 		struct subchannel *sch;
 
-		sch = get_subchannel_by_schid(irq);
+		sch = get_subchannel_by_schid(schid);
 		if (sch) {
 			/* Already known. */
 			put_device(&sch->dev);
 			continue;
 		}
-		ret = css_probe_device(irq);
+		ret = css_probe_device(schid);
 		if (ret == -ENXIO)
 			break; /* We're through. */
 		if (ret == -ENOMEM)
@@ -248,7 +249,7 @@ s390_redo_validation (void)
 			 * panic.
 			 */
 			break;
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 }
 
 /*
@@ -289,12 +290,12 @@ static int cio_ignore_read (char *page, char **start, off_t off,
 	len = 0;
 	for (devno = off; /* abuse the page variable
 			   * as counter, see fs/proc/generic.c */
-	     devno < __MAX_SUBCHANNELS && len + entry_size < count; devno++) {
+	     devno < __MAX_SUBCHANNEL && len + entry_size < count; devno++) {
 		if (!test_bit(devno, bl_dev))
 			continue;
 		len += sprintf(page + len, "0.0.%04lx", devno);
 		if (test_bit(devno + 1, bl_dev)) { /* print range */
-			while (++devno < __MAX_SUBCHANNELS)
+			while (++devno < __MAX_SUBCHANNEL)
 				if (!test_bit(devno, bl_dev))
 					break;
 			len += sprintf(page + len, "-0.0.%04lx", --devno);
@@ -302,7 +303,7 @@ static int cio_ignore_read (char *page, char **start, off_t off,
 		len += sprintf(page + len, "\n");
 	}
 
-	if (devno < __MAX_SUBCHANNELS)
+	if (devno < __MAX_SUBCHANNEL)
 		*eof = 1;
 	*start = (char *) (devno - off); /* number of checked entries */
 	return len;
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index fa3c23b80e3..aff5d149b72 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -104,8 +104,8 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
 		.code   = 0x0004,
 	};
 
-	ssd_area->f_sch = sch->irq;
-	ssd_area->l_sch = sch->irq;
+	ssd_area->f_sch = sch->schid.sch_no;
+	ssd_area->l_sch = sch->schid.sch_no;
 
 	ccode = chsc(ssd_area);
 	if (ccode > 0) {
@@ -147,7 +147,8 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
 	 */
 	if (ssd_area->st > 3) { /* uhm, that looks strange... */
 		CIO_CRW_EVENT(0, "Strange subchannel type %d"
-			      " for sch %04x\n", ssd_area->st, sch->irq);
+			      " for sch %04x\n", ssd_area->st,
+			      sch->schid.sch_no);
 		/*
 		 * There may have been a new subchannel type defined in the
 		 * time since this code was written; since we don't know which
@@ -157,7 +158,7 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
 	} else {
 		const char *type[4] = {"I/O", "chsc", "message", "ADM"};
 		CIO_CRW_EVENT(6, "ssd: sch %04x is %s subchannel\n",
-			      sch->irq, type[ssd_area->st]);
+			      sch->schid.sch_no, type[ssd_area->st]);
 
 		sch->ssd_info.valid = 1;
 		sch->ssd_info.type = ssd_area->st;
@@ -232,7 +233,7 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
 	mask = 0x80 >> j;
 	spin_lock(&sch->lock);
 
-	stsch(sch->irq, &schib);
+	stsch(sch->schid, &schib);
 	if (!schib.pmcw.dnv)
 		goto out_unreg;
 	memcpy(&sch->schib, &schib, sizeof(struct schib));
@@ -284,7 +285,7 @@ out_unlock:
 out_unreg:
 	spin_unlock(&sch->lock);
 	sch->lpm = 0;
-	if (css_enqueue_subchannel_slow(sch->irq)) {
+	if (css_enqueue_subchannel_slow(sch->schid)) {
 		css_clear_subchannel_slow_list();
 		need_rescan = 1;
 	}
@@ -337,7 +338,7 @@ s390_process_res_acc_sch(u8 chpid, __u16 fla, u32 fla_mask,
 	 * new path information and eventually check for logically
 	 * offline chpids.
 	 */
-	ccode = stsch(sch->irq, &sch->schib);
+	ccode = stsch(sch->schid, &sch->schib);
 	if (ccode > 0)
 		return 0;
 
@@ -348,7 +349,8 @@ static int
 s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
 {
 	struct subchannel *sch;
-	int irq, rc;
+	int rc;
+	struct subchannel_id schid;
 	char dbf_txt[15];
 
 	sprintf(dbf_txt, "accpr%x", chpid);
@@ -370,10 +372,11 @@ s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
 		return 0; /* no need to do the rest */
 
 	rc = 0;
-	for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+	init_subchannel_id(&schid);
+	do {
 		int chp_mask, old_lpm;
 
-		sch = get_subchannel_by_schid(irq);
+		sch = get_subchannel_by_schid(schid);
 		if (!sch) {
 			struct schib schib;
 			int ret;
@@ -385,7 +388,7 @@ s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
 			 * that beast may be on we'll have to do a stsch
 			 * on all devices, grr...
 			 */
-			if (stsch(irq, &schib)) {
+			if (stsch(schid, &schib)) {
 				/* We're through */
 				if (need_rescan)
 					rc = -EAGAIN;
@@ -396,7 +399,7 @@ s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
 				continue;
 			}
 			/* Put it on the slow path. */
-			ret = css_enqueue_subchannel_slow(irq);
+			ret = css_enqueue_subchannel_slow(schid);
 			if (ret) {
 				css_clear_subchannel_slow_list();
 				need_rescan = 1;
@@ -428,7 +431,7 @@ s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
 		put_device(&sch->dev);
 		if (fla_mask == 0xffff)
 			break;
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 	return rc;
 }
 
@@ -608,7 +611,8 @@ static int
 chp_add(int chpid)
 {
 	struct subchannel *sch;
-	int irq, ret, rc;
+	int ret, rc;
+	struct subchannel_id schid;
 	char dbf_txt[15];
 
 	if (!get_chp_status(chpid))
@@ -618,14 +622,15 @@ chp_add(int chpid)
 	CIO_TRACE_EVENT(2, dbf_txt);
 
 	rc = 0;
-	for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+	init_subchannel_id(&schid);
+	do {
 		int i;
 
-		sch = get_subchannel_by_schid(irq);
+		sch = get_subchannel_by_schid(schid);
 		if (!sch) {
 			struct schib schib;
 
-			if (stsch(irq, &schib)) {
+			if (stsch(schid, &schib)) {
 				/* We're through */
 				if (need_rescan)
 					rc = -EAGAIN;
@@ -636,7 +641,7 @@ chp_add(int chpid)
 				continue;
 			}
 			/* Put it on the slow path. */
-			ret = css_enqueue_subchannel_slow(irq);
+			ret = css_enqueue_subchannel_slow(schid);
 			if (ret) {
 				css_clear_subchannel_slow_list();
 				need_rescan = 1;
@@ -648,7 +653,7 @@ chp_add(int chpid)
 		spin_lock(&sch->lock);
 		for (i=0; i<8; i++)
 			if (sch->schib.pmcw.chpid[i] == chpid) {
-				if (stsch(sch->irq, &sch->schib) != 0) {
+				if (stsch(sch->schid, &sch->schib) != 0) {
 					/* Endgame. */
 					spin_unlock(&sch->lock);
 					return rc;
@@ -669,7 +674,7 @@ chp_add(int chpid)
 
 		spin_unlock(&sch->lock);
 		put_device(&sch->dev);
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 	return rc;
 }
 
@@ -702,7 +707,7 @@ __check_for_io_and_kill(struct subchannel *sch, int index)
 	if (!device_is_online(sch))
 		/* cio could be doing I/O. */
 		return 0;
-	cc = stsch(sch->irq, &sch->schib);
+	cc = stsch(sch->schid, &sch->schib);
 	if (cc)
 		return 0;
 	if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
@@ -743,7 +748,7 @@ __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
 			 * just varied off path. Then kill it.
 			 */
 			if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
-				if (css_enqueue_subchannel_slow(sch->irq)) {
+				if (css_enqueue_subchannel_slow(sch->schid)) {
 					css_clear_subchannel_slow_list();
 					need_rescan = 1;
 				}
@@ -789,7 +794,8 @@ static int
 s390_vary_chpid( __u8 chpid, int on)
 {
 	char dbf_text[15];
-	int status, irq, ret;
+	int status, ret;
+	struct subchannel_id schid;
 	struct subchannel *sch;
 
 	sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
@@ -818,26 +824,27 @@ s390_vary_chpid( __u8 chpid, int on)
 	if (!on)
 		goto out;
 	/* Scan for new devices on varied on path. */
-	for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+	init_subchannel_id(&schid);
+	do {
 		struct schib schib;
 
 		if (need_rescan)
 			break;
-		sch = get_subchannel_by_schid(irq);
+		sch = get_subchannel_by_schid(schid);
 		if (sch) {
 			put_device(&sch->dev);
 			continue;
 		}
-		if (stsch(irq, &schib))
+		if (stsch(schid, &schib))
 			/* We're through */
 			break;
 		/* Put it on the slow path. */
-		ret = css_enqueue_subchannel_slow(irq);
+		ret = css_enqueue_subchannel_slow(schid);
 		if (ret) {
 			css_clear_subchannel_slow_list();
 			need_rescan = 1;
 		}
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 out:
 	if (need_rescan || css_slow_subchannels_exist())
 		queue_work(slow_path_wq, &slow_path_work);
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 185bc73c3ec..396bada65f8 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -135,7 +135,7 @@ cio_tpi(void)
 		return 0;
 	irb = (struct irb *) __LC_IRB;
 	/* Store interrupt response block to lowcore. */
-	if (tsch (tpi_info->irq, irb) != 0)
+	if (tsch (tpi_info->schid, irb) != 0)
 		/* Not status pending or not operational. */
 		return 1;
 	sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
@@ -163,10 +163,10 @@ cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
 	else
 		sch->lpm = 0;
 
-	stsch (sch->irq, &sch->schib);
+	stsch (sch->schid, &sch->schib);
 
 	CIO_MSG_EVENT(0, "cio_start: 'not oper' status for "
-		      "subchannel %04x!\n", sch->irq);
+		      "subchannel %04x!\n", sch->schid.sch_no);
 	sprintf(dbf_text, "no%s", sch->dev.bus_id);
 	CIO_TRACE_EVENT(0, dbf_text);
 	CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
@@ -204,7 +204,7 @@ cio_start_key (struct subchannel *sch,	/* subchannel structure */
 	sch->orb.key = key >> 4;
 	/* issue "Start Subchannel" */
 	sch->orb.cpa = (__u32) __pa (cpa);
-	ccode = ssch (sch->irq, &sch->orb);
+	ccode = ssch (sch->schid, &sch->orb);
 
 	/* process condition code */
 	sprintf (dbf_txt, "ccode:%d", ccode);
@@ -243,7 +243,7 @@ cio_resume (struct subchannel *sch)
 	CIO_TRACE_EVENT (4, "resIO");
 	CIO_TRACE_EVENT (4, sch->dev.bus_id);
 
-	ccode = rsch (sch->irq);
+	ccode = rsch (sch->schid);
 
 	sprintf (dbf_txt, "ccode:%d", ccode);
 	CIO_TRACE_EVENT (4, dbf_txt);
@@ -283,7 +283,7 @@ cio_halt(struct subchannel *sch)
 	/*
 	 * Issue "Halt subchannel" and process condition code
 	 */
-	ccode = hsch (sch->irq);
+	ccode = hsch (sch->schid);
 
 	sprintf (dbf_txt, "ccode:%d", ccode);
 	CIO_TRACE_EVENT (2, dbf_txt);
@@ -318,7 +318,7 @@ cio_clear(struct subchannel *sch)
 	/*
 	 * Issue "Clear subchannel" and process condition code
 	 */
-	ccode = csch (sch->irq);
+	ccode = csch (sch->schid);
 
 	sprintf (dbf_txt, "ccode:%d", ccode);
 	CIO_TRACE_EVENT (2, dbf_txt);
@@ -351,7 +351,7 @@ cio_cancel (struct subchannel *sch)
 	CIO_TRACE_EVENT (2, "cancelIO");
 	CIO_TRACE_EVENT (2, sch->dev.bus_id);
 
-	ccode = xsch (sch->irq);
+	ccode = xsch (sch->schid);
 
 	sprintf (dbf_txt, "ccode:%d", ccode);
 	CIO_TRACE_EVENT (2, dbf_txt);
@@ -359,7 +359,7 @@ cio_cancel (struct subchannel *sch)
 	switch (ccode) {
 	case 0:		/* success */
 		/* Update information in scsw. */
-		stsch (sch->irq, &sch->schib);
+		stsch (sch->schid, &sch->schib);
 		return 0;
 	case 1:		/* status pending */
 		return -EBUSY;
@@ -381,7 +381,7 @@ cio_modify (struct subchannel *sch)
 
 	ret = 0;
 	for (retry = 0; retry < 5; retry++) {
-		ccode = msch_err (sch->irq, &sch->schib);
+		ccode = msch_err (sch->schid, &sch->schib);
 		if (ccode < 0)	/* -EIO if msch gets a program check. */
 			return ccode;
 		switch (ccode) {
@@ -414,7 +414,7 @@ cio_enable_subchannel (struct subchannel *sch, unsigned int isc)
 	CIO_TRACE_EVENT (2, "ensch");
 	CIO_TRACE_EVENT (2, sch->dev.bus_id);
 
-	ccode = stsch (sch->irq, &sch->schib);
+	ccode = stsch (sch->schid, &sch->schib);
 	if (ccode)
 		return -ENODEV;
 
@@ -432,13 +432,13 @@ cio_enable_subchannel (struct subchannel *sch, unsigned int isc)
 			 */
 			sch->schib.pmcw.csense = 0;
 		if (ret == 0) {
-			stsch (sch->irq, &sch->schib);
+			stsch (sch->schid, &sch->schib);
 			if (sch->schib.pmcw.ena)
 				break;
 		}
 		if (ret == -EBUSY) {
 			struct irb irb;
-			if (tsch(sch->irq, &irb) != 0)
+			if (tsch(sch->schid, &irb) != 0)
 				break;
 		}
 	}
@@ -461,7 +461,7 @@ cio_disable_subchannel (struct subchannel *sch)
 	CIO_TRACE_EVENT (2, "dissch");
 	CIO_TRACE_EVENT (2, sch->dev.bus_id);
 
-	ccode = stsch (sch->irq, &sch->schib);
+	ccode = stsch (sch->schid, &sch->schib);
 	if (ccode == 3)		/* Not operational. */
 		return -ENODEV;
 
@@ -485,7 +485,7 @@ cio_disable_subchannel (struct subchannel *sch)
 			 */
 			break;
 		if (ret == 0) {
-			stsch (sch->irq, &sch->schib);
+			stsch (sch->schid, &sch->schib);
 			if (!sch->schib.pmcw.ena)
 				break;
 		}
@@ -508,12 +508,12 @@ cio_disable_subchannel (struct subchannel *sch)
  *   -ENODEV for subchannels with invalid device number or blacklisted devices
  */
 int
-cio_validate_subchannel (struct subchannel *sch, unsigned int irq)
+cio_validate_subchannel (struct subchannel *sch, struct subchannel_id schid)
 {
 	char dbf_txt[15];
 	int ccode;
 
-	sprintf (dbf_txt, "valsch%x", irq);
+	sprintf (dbf_txt, "valsch%x", schid.sch_no);
 	CIO_TRACE_EVENT (4, dbf_txt);
 
 	/* Nuke all fields. */
@@ -522,17 +522,17 @@ cio_validate_subchannel (struct subchannel *sch, unsigned int irq)
 	spin_lock_init(&sch->lock);
 
 	/* Set a name for the subchannel */
-	snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.0.%04x", irq);
+	snprintf (sch->dev.bus_id, BUS_ID_SIZE, "0.0.%04x", schid.sch_no);
 
 	/*
 	 * The first subchannel that is not-operational (ccode==3)
 	 *  indicates that there aren't any more devices available.
 	 */
-	sch->irq = irq;
-	ccode = stsch (irq, &sch->schib);
+	ccode = stsch (schid, &sch->schib);
 	if (ccode)
 		return -ENXIO;
 
+	sch->schid = schid;
 	/* Copy subchannel type from path management control word. */
 	sch->st = sch->schib.pmcw.st;
 
@@ -543,7 +543,7 @@ cio_validate_subchannel (struct subchannel *sch, unsigned int irq)
 		CIO_DEBUG(KERN_INFO, 0,
 			  "Subchannel %04X reports "
 			  "non-I/O subchannel type %04X\n",
-			  sch->irq, sch->st);
+			  sch->schid.sch_no, sch->st);
 		/* We stop here for non-io subchannels. */
 		return sch->st;
 	}
@@ -573,7 +573,7 @@ cio_validate_subchannel (struct subchannel *sch, unsigned int irq)
 	CIO_DEBUG(KERN_INFO, 0,
 		  "Detected device %04X on subchannel %04X"
 		  " - PIM = %02X, PAM = %02X, POM = %02X\n",
-		  sch->schib.pmcw.dev, sch->irq, sch->schib.pmcw.pim,
+		  sch->schib.pmcw.dev, sch->schid.sch_no, sch->schib.pmcw.pim,
 		  sch->schib.pmcw.pam, sch->schib.pmcw.pom);
 
 	/*
@@ -632,7 +632,7 @@ do_IRQ (struct pt_regs *regs)
 		if (sch)
 			spin_lock(&sch->lock);
 		/* Store interrupt response block to lowcore. */
-		if (tsch (tpi_info->irq, irb) == 0 && sch) {
+		if (tsch (tpi_info->schid, irb) == 0 && sch) {
 			/* Keep subchannel information word up to date. */
 			memcpy (&sch->schib.scsw, &irb->scsw,
 				sizeof (irb->scsw));
@@ -693,26 +693,28 @@ wait_cons_dev (void)
 static int
 cio_console_irq(void)
 {
-	int irq;
+	struct subchannel_id schid;
 	
+	init_subchannel_id(&schid);
 	if (console_irq != -1) {
 		/* VM provided us with the irq number of the console. */
-		if (stsch(console_irq, &console_subchannel.schib) != 0 ||
+		schid.sch_no = console_irq;
+		if (stsch(schid, &console_subchannel.schib) != 0 ||
 		    !console_subchannel.schib.pmcw.dnv)
 			return -1;
 		console_devno = console_subchannel.schib.pmcw.dev;
 	} else if (console_devno != -1) {
 		/* At least the console device number is known. */
-		for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
-			if (stsch(irq, &console_subchannel.schib) != 0)
+		do {
+			if (stsch(schid, &console_subchannel.schib) != 0)
 				break;
 			if (console_subchannel.schib.pmcw.dnv &&
 			    console_subchannel.schib.pmcw.dev ==
 			    console_devno) {
-				console_irq = irq;
+				console_irq = schid.sch_no;
 				break;
 			}
-		}
+		} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 		if (console_irq == -1)
 			return -1;
 	} else {
@@ -729,6 +731,7 @@ struct subchannel *
 cio_probe_console(void)
 {
 	int irq, ret;
+	struct subchannel_id schid;
 
 	if (xchg(&console_subchannel_in_use, 1) != 0)
 		return ERR_PTR(-EBUSY);
@@ -738,7 +741,9 @@ cio_probe_console(void)
 		return ERR_PTR(-ENODEV);
 	}
 	memset(&console_subchannel, 0, sizeof(struct subchannel));
-	ret = cio_validate_subchannel(&console_subchannel, irq);
+	init_subchannel_id(&schid);
+	schid.sch_no = irq;
+	ret = cio_validate_subchannel(&console_subchannel, schid);
 	if (ret) {
 		console_subchannel_in_use = 0;
 		return ERR_PTR(-ENODEV);
@@ -770,11 +775,11 @@ cio_release_console(void)
 
 /* Bah... hack to catch console special sausages. */
 int
-cio_is_console(int irq)
+cio_is_console(struct subchannel_id schid)
 {
 	if (!console_subchannel_in_use)
 		return 0;
-	return (irq == console_subchannel.irq);
+	return schid_equal(&schid, &console_subchannel.schid);
 }
 
 struct subchannel *
@@ -787,7 +792,7 @@ cio_get_console_subchannel(void)
 
 #endif
 static inline int
-__disable_subchannel_easy(unsigned int schid, struct schib *schib)
+__disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
 {
 	int retry, cc;
 
@@ -805,7 +810,7 @@ __disable_subchannel_easy(unsigned int schid, struct schib *schib)
 }
 
 static inline int
-__clear_subchannel_easy(unsigned int schid)
+__clear_subchannel_easy(struct subchannel_id schid)
 {
 	int retry;
 
@@ -815,8 +820,8 @@ __clear_subchannel_easy(unsigned int schid)
 		struct tpi_info ti;
 
 		if (tpi(&ti)) {
-			tsch(ti.irq, (struct irb *)__LC_IRB);
-			if (ti.irq == schid)
+			tsch(ti.schid, (struct irb *)__LC_IRB);
+			if (schid_equal(&ti.schid, &schid))
 				return 0;
 		}
 		udelay(100);
@@ -830,10 +835,11 @@ extern void do_reipl(unsigned long devno);
 void
 clear_all_subchannels(void)
 {
-	unsigned int schid;
+	struct subchannel_id schid;
 
 	local_irq_disable();
-	for (schid=0;schid<=highest_subchannel;schid++) {
+	init_subchannel_id(&schid);
+	do {
 		struct schib schib;
 		if (stsch(schid, &schib))
 			break; /* break out of the loop */
@@ -849,7 +855,7 @@ clear_all_subchannels(void)
 			stsch(schid, &schib);
 			__disable_subchannel_easy(schid, &schib);
 		}
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 }
 
 /* Make sure all subchannels are quiet before we re-ipl an lpar. */
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index c50a9da420a..0ca987344e0 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -1,6 +1,8 @@
 #ifndef S390_CIO_H
 #define S390_CIO_H
 
+#include "schid.h"
+
 /*
  * where we put the ssd info
  */
@@ -83,7 +85,7 @@ struct orb {
 
 /* subchannel data structure used by I/O subroutines */
 struct subchannel {
-	unsigned int irq;	/* aka. subchannel number */
+	struct subchannel_id schid;
 	spinlock_t lock;	/* subchannel lock */
 
 	enum {
@@ -114,7 +116,7 @@ struct subchannel {
 
 #define to_subchannel(n) container_of(n, struct subchannel, dev)
 
-extern int cio_validate_subchannel (struct subchannel *, unsigned int);
+extern int cio_validate_subchannel (struct subchannel *, struct subchannel_id);
 extern int cio_enable_subchannel (struct subchannel *, unsigned int);
 extern int cio_disable_subchannel (struct subchannel *);
 extern int cio_cancel (struct subchannel *);
@@ -127,14 +129,15 @@ extern int cio_cancel (struct subchannel *);
 extern int cio_set_options (struct subchannel *, int);
 extern int cio_get_options (struct subchannel *);
 extern int cio_modify (struct subchannel *);
+
 /* Use with care. */
 #ifdef CONFIG_CCW_CONSOLE
 extern struct subchannel *cio_probe_console(void);
 extern void cio_release_console(void);
-extern int cio_is_console(int irq);
+extern int cio_is_console(struct subchannel_id);
 extern struct subchannel *cio_get_console_subchannel(void);
 #else
-#define cio_is_console(irq) 0
+#define cio_is_console(schid) 0
 #define cio_get_console_subchannel() NULL
 #endif
 
diff --git a/drivers/s390/cio/cmf.c b/drivers/s390/cio/cmf.c
index b978f7fe832..0b03714e696 100644
--- a/drivers/s390/cio/cmf.c
+++ b/drivers/s390/cio/cmf.c
@@ -1,5 +1,5 @@
 /*
- * linux/drivers/s390/cio/cmf.c ($Revision: 1.16 $)
+ * linux/drivers/s390/cio/cmf.c ($Revision: 1.19 $)
  *
  * Linux on zSeries Channel Measurement Facility support
  *
@@ -178,7 +178,7 @@ set_schib(struct ccw_device *cdev, u32 mme, int mbfc, unsigned long address)
 	/* msch can silently fail, so do it again if necessary */
 	for (retry = 0; retry < 3; retry++) {
 		/* prepare schib */
-		stsch(sch->irq, schib);
+		stsch(sch->schid, schib);
 		schib->pmcw.mme  = mme;
 		schib->pmcw.mbfc = mbfc;
 		/* address can be either a block address or a block index */
@@ -188,7 +188,7 @@ set_schib(struct ccw_device *cdev, u32 mme, int mbfc, unsigned long address)
 			schib->pmcw.mbi = address;
 
 		/* try to submit it */
-		switch(ret = msch_err(sch->irq, schib)) {
+		switch(ret = msch_err(sch->schid, schib)) {
 			case 0:
 				break;
 			case 1:
@@ -202,7 +202,7 @@ set_schib(struct ccw_device *cdev, u32 mme, int mbfc, unsigned long address)
 				ret = -EINVAL;
 				break;
 		}
-		stsch(sch->irq, schib); /* restore the schib */
+		stsch(sch->schid, schib); /* restore the schib */
 
 		if (ret)
 			break;
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 7e4d57b4266..5137dafd1e8 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -33,7 +33,7 @@ struct device css_bus_device = {
 };
 
 static struct subchannel *
-css_alloc_subchannel(int irq)
+css_alloc_subchannel(struct subchannel_id schid)
 {
 	struct subchannel *sch;
 	int ret;
@@ -41,13 +41,11 @@ css_alloc_subchannel(int irq)
 	sch = kmalloc (sizeof (*sch), GFP_KERNEL | GFP_DMA);
 	if (sch == NULL)
 		return ERR_PTR(-ENOMEM);
-	ret = cio_validate_subchannel (sch, irq);
+	ret = cio_validate_subchannel (sch, schid);
 	if (ret < 0) {
 		kfree(sch);
 		return ERR_PTR(ret);
 	}
-	if (irq > highest_subchannel)
-		highest_subchannel = irq;
 
 	if (sch->st != SUBCHANNEL_TYPE_IO) {
 		/* For now we ignore all non-io subchannels. */
@@ -87,7 +85,7 @@ css_subchannel_release(struct device *dev)
 	struct subchannel *sch;
 
 	sch = to_subchannel(dev);
-	if (!cio_is_console(sch->irq))
+	if (!cio_is_console(sch->schid))
 		kfree(sch);
 }
 
@@ -114,12 +112,12 @@ css_register_subchannel(struct subchannel *sch)
 }
 
 int
-css_probe_device(int irq)
+css_probe_device(struct subchannel_id schid)
 {
 	int ret;
 	struct subchannel *sch;
 
-	sch = css_alloc_subchannel(irq);
+	sch = css_alloc_subchannel(schid);
 	if (IS_ERR(sch))
 		return PTR_ERR(sch);
 	ret = css_register_subchannel(sch);
@@ -132,26 +130,26 @@ static int
 check_subchannel(struct device * dev, void * data)
 {
 	struct subchannel *sch;
-	int irq = (unsigned long)data;
+	struct subchannel_id *schid = data;
 
 	sch = to_subchannel(dev);
-	return (sch->irq == irq);
+	return schid_equal(&sch->schid, schid);
 }
 
 struct subchannel *
-get_subchannel_by_schid(int irq)
+get_subchannel_by_schid(struct subchannel_id schid)
 {
 	struct device *dev;
 
 	dev = bus_find_device(&css_bus_type, NULL,
-			      (void *)(unsigned long)irq, check_subchannel);
+			      (void *)&schid, check_subchannel);
 
 	return dev ? to_subchannel(dev) : NULL;
 }
 
 
 static inline int
-css_get_subchannel_status(struct subchannel *sch, int schid)
+css_get_subchannel_status(struct subchannel *sch, struct subchannel_id schid)
 {
 	struct schib schib;
 	int cc;
@@ -170,13 +168,13 @@ css_get_subchannel_status(struct subchannel *sch, int schid)
 }
 	
 static int
-css_evaluate_subchannel(int irq, int slow)
+css_evaluate_subchannel(struct subchannel_id schid, int slow)
 {
 	int event, ret, disc;
 	struct subchannel *sch;
 	unsigned long flags;
 
-	sch = get_subchannel_by_schid(irq);
+	sch = get_subchannel_by_schid(schid);
 	disc = sch ? device_is_disconnected(sch) : 0;
 	if (disc && slow) {
 		if (sch)
@@ -194,9 +192,10 @@ css_evaluate_subchannel(int irq, int slow)
 			put_device(&sch->dev);
 		return -EAGAIN; /* Will be done on the slow path. */
 	}
-	event = css_get_subchannel_status(sch, irq);
+	event = css_get_subchannel_status(sch, schid);
 	CIO_MSG_EVENT(4, "Evaluating schid %04x, event %d, %s, %s path.\n",
-		      irq, event, sch?(disc?"disconnected":"normal"):"unknown",
+		      schid.sch_no, event,
+		      sch?(disc?"disconnected":"normal"):"unknown",
 		      slow?"slow":"fast");
 	switch (event) {
 	case CIO_NO_PATH:
@@ -253,7 +252,7 @@ css_evaluate_subchannel(int irq, int slow)
 			sch->schib.pmcw.intparm = 0;
 			cio_modify(sch);
 			put_device(&sch->dev);
-			ret = css_probe_device(irq);
+			ret = css_probe_device(schid);
 		} else {
 			/*
 			 * We can't immediately deregister the disconnected
@@ -272,7 +271,7 @@ css_evaluate_subchannel(int irq, int slow)
 			device_trigger_reprobe(sch);
 			spin_unlock_irqrestore(&sch->lock, flags);
 		}
-		ret = sch ? 0 : css_probe_device(irq);
+		ret = sch ? 0 : css_probe_device(schid);
 		break;
 	default:
 		BUG();
@@ -284,10 +283,12 @@ css_evaluate_subchannel(int irq, int slow)
 static void
 css_rescan_devices(void)
 {
-	int irq, ret;
+	int ret;
+	struct subchannel_id schid;
 
-	for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
-		ret = css_evaluate_subchannel(irq, 1);
+	init_subchannel_id(&schid);
+	do {
+		ret = css_evaluate_subchannel(schid, 1);
 		/* No more memory. It doesn't make sense to continue. No
 		 * panic because this can happen in midflight and just
 		 * because we can't use a new device is no reason to crash
@@ -297,12 +298,12 @@ css_rescan_devices(void)
 		/* -ENXIO indicates that there are no more subchannels. */
 		if (ret == -ENXIO)
 			break;
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 }
 
 struct slow_subchannel {
 	struct list_head slow_list;
-	unsigned long schid;
+	struct subchannel_id schid;
 };
 
 static LIST_HEAD(slow_subchannels_head);
@@ -357,20 +358,24 @@ int
 css_process_crw(int irq)
 {
 	int ret;
+	struct subchannel_id mchk_schid;
 
 	CIO_CRW_EVENT(2, "source is subchannel %04X\n", irq);
 
 	if (need_rescan)
 		/* We need to iterate all subchannels anyway. */
 		return -EAGAIN;
+
+	init_subchannel_id(&mchk_schid);
+	mchk_schid.sch_no = irq;
 	/* 
 	 * Since we are always presented with IPI in the CRW, we have to
 	 * use stsch() to find out if the subchannel in question has come
 	 * or gone.
 	 */
-	ret = css_evaluate_subchannel(irq, 0);
+	ret = css_evaluate_subchannel(mchk_schid, 0);
 	if (ret == -EAGAIN) {
-		if (css_enqueue_subchannel_slow(irq)) {
+		if (css_enqueue_subchannel_slow(mchk_schid)) {
 			css_clear_subchannel_slow_list();
 			need_rescan = 1;
 		}
@@ -404,7 +409,8 @@ css_generate_pgid(void)
 static int __init
 init_channel_subsystem (void)
 {
-	int ret, irq;
+	int ret;
+	struct subchannel_id schid;
 
 	if (chsc_determine_css_characteristics() == 0)
 		css_characteristics_avail = 1;
@@ -420,13 +426,14 @@ init_channel_subsystem (void)
 
 	ctl_set_bit(6, 28);
 
-	for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+	init_subchannel_id(&schid);
+	do {
 		struct subchannel *sch;
 
-		if (cio_is_console(irq))
+		if (cio_is_console(schid))
 			sch = cio_get_console_subchannel();
 		else {
-			sch = css_alloc_subchannel(irq);
+			sch = css_alloc_subchannel(schid);
 			if (IS_ERR(sch))
 				ret = PTR_ERR(sch);
 			else
@@ -448,7 +455,7 @@ init_channel_subsystem (void)
 		 * console subchannel.
 		 */
 		css_register_subchannel(sch);
-	}
+	} while (schid.sch_no++ < __MAX_SUBCHANNEL);
 	return 0;
 
 out_bus:
@@ -482,7 +489,7 @@ struct bus_type css_bus_type = {
 subsys_initcall(init_channel_subsystem);