Skip to content

Commit

Permalink
[S390] cio: kernel stack overflow.
Browse files Browse the repository at this point in the history
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>
  • Loading branch information
Heiko Carstens authored and Martin Schwidefsky committed Aug 30, 2006
1 parent 8f61701 commit 292888c
Show file tree
Hide file tree
Showing 4 changed files with 22 additions and 37 deletions.
14 changes: 5 additions & 9 deletions drivers/s390/cio/ccwgroup.c
Original file line number Diff line number Diff line change
Expand Up @@ -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);
Expand Down Expand Up @@ -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);
}
Expand Down
6 changes: 2 additions & 4 deletions drivers/s390/cio/chsc.c
Original file line number Diff line number Diff line change
Expand Up @@ -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. */
Expand Down
19 changes: 7 additions & 12 deletions drivers/s390/cio/device.c
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand Down Expand Up @@ -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);
Expand Down Expand Up @@ -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;
Expand Down
20 changes: 8 additions & 12 deletions drivers/s390/cio/device_fsm.c
Original file line number Diff line number Diff line change
Expand Up @@ -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) {
Expand Down Expand Up @@ -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,
Expand Down

0 comments on commit 292888c

Please sign in to comment.