From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Wed, 30 Aug 2006 12:33:35 +0000 (+0200)
Subject: [S390] cio: kernel stack overflow.
X-Git-Tag: v2.6.18-rc6~31^2~2
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=292888c81e74115db5e5a4a838f730a7c3662982;p=linux-2.6

[S390] cio: kernel stack overflow.

Use different kind of assignment to make sure gcc doesn't create code
that creates temp variables on the stack, assigns values to it and
copies the content of the whole temp variable to the destination.
This reduces stack usage of e.g. ccwgroup_driver_register from 976
to 48 bytes instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index 3cba6c9fab..38954f5cd1 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -183,11 +183,9 @@ ccwgroup_create(struct device *root,
 
 	gdev->creator_id = creator_id;
 	gdev->count = argc;
-	gdev->dev = (struct device ) {
-		.bus = &ccwgroup_bus_type,
-		.parent = root,
-		.release = ccwgroup_release,
-	};
+	gdev->dev.bus = &ccwgroup_bus_type;
+	gdev->dev.parent = root;
+	gdev->dev.release = ccwgroup_release;
 
 	snprintf (gdev->dev.bus_id, BUS_ID_SIZE, "%s",
 			gdev->cdev[0]->dev.bus_id);
@@ -391,10 +389,8 @@ int
 ccwgroup_driver_register (struct ccwgroup_driver *cdriver)
 {
 	/* register our new driver with the core */
-	cdriver->driver = (struct device_driver) {
-		.bus = &ccwgroup_bus_type,
-		.name = cdriver->name,
-	};
+	cdriver->driver.bus = &ccwgroup_bus_type;
+	cdriver->driver.name = cdriver->name;
 
 	return driver_register(&cdriver->driver);
 }
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index 61ce3f1d52..6405e9bd6e 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -1391,10 +1391,8 @@ new_channel_path(int chpid)
 	/* fill in status, etc. */
 	chp->id = chpid;
 	chp->state = 1;
-	chp->dev = (struct device) {
-		.parent  = &css[0]->device,
-		.release = chp_release,
-	};
+	chp->dev.parent = &css[0]->device;
+	chp->dev.release = chp_release;
 	snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
 
 	/* Obtain channel path description and fill it in. */
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 585fa04233..646da56404 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -556,12 +556,11 @@ get_disc_ccwdev_by_devno(unsigned int devno, unsigned int ssid,
 			 struct ccw_device *sibling)
 {
 	struct device *dev;
-	struct match_data data = {
-		.devno   = devno,
-		.ssid    = ssid,
-		.sibling = sibling,
-	};
+	struct match_data data;
 
+	data.devno = devno;
+	data.ssid = ssid;
+	data.sibling = sibling;
 	dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 
 	return dev ? to_ccwdev(dev) : NULL;
@@ -835,10 +834,8 @@ io_subchannel_probe (struct subchannel *sch)
 		return -ENOMEM;
 	}
 	atomic_set(&cdev->private->onoff, 0);
-	cdev->dev = (struct device) {
-		.parent = &sch->dev,
-		.release = ccw_device_release,
-	};
+	cdev->dev.parent = &sch->dev;
+	cdev->dev.release = ccw_device_release;
 	INIT_LIST_HEAD(&cdev->private->kick_work.entry);
 	/* Do first half of device_register. */
 	device_initialize(&cdev->dev);
@@ -977,9 +974,7 @@ ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
 	int rc;
 
 	/* Initialize the ccw_device structure. */
-	cdev->dev = (struct device) {
-		.parent = &sch->dev,
-	};
+	cdev->dev.parent= &sch->dev;
 	rc = io_subchannel_recog(cdev, sch);
 	if (rc)
 		return rc;
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 6d91c2eb20..35e162ba6d 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -267,12 +267,10 @@ ccw_device_recog_done(struct ccw_device *cdev, int state)
 			notify = 1;
 		}
 		/* fill out sense information */
-		cdev->id = (struct ccw_device_id) {
-			.cu_type   = cdev->private->senseid.cu_type,
-			.cu_model  = cdev->private->senseid.cu_model,
-			.dev_type  = cdev->private->senseid.dev_type,
-			.dev_model = cdev->private->senseid.dev_model,
-		};
+		cdev->id.cu_type   = cdev->private->senseid.cu_type;
+		cdev->id.cu_model  = cdev->private->senseid.cu_model;
+		cdev->id.dev_type  = cdev->private->senseid.dev_type;
+		cdev->id.dev_model = cdev->private->senseid.dev_model;
 		if (notify) {
 			cdev->private->state = DEV_STATE_OFFLINE;
 			if (same_dev) {
@@ -566,12 +564,10 @@ ccw_device_verify_done(struct ccw_device *cdev, int err)
 		/* Deliver fake irb to device driver, if needed. */
 		if (cdev->private->flags.fake_irb) {
 			memset(&cdev->private->irb, 0, sizeof(struct irb));
-			cdev->private->irb.scsw = (struct scsw) {
-				.cc = 1,
-				.fctl = SCSW_FCTL_START_FUNC,
-				.actl = SCSW_ACTL_START_PEND,
-				.stctl = SCSW_STCTL_STATUS_PEND,
-			};
+			cdev->private->irb.scsw.cc = 1;
+			cdev->private->irb.scsw.fctl = SCSW_FCTL_START_FUNC;
+			cdev->private->irb.scsw.actl = SCSW_ACTL_START_PEND;
+			cdev->private->irb.scsw.stctl = SCSW_STCTL_STATUS_PEND;
 			cdev->private->flags.fake_irb = 0;
 			if (cdev->handler)
 				cdev->handler(cdev, cdev->private->intparm,