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TTY: con3215, centralize allocation 

There are two copies of allocations of device information. One of them
is totally broken. See:
raw->cdev = cdev;
raw->inbuf = (char *) raw + sizeof(struct raw3215_info);
memset(raw, 0, sizeof(struct raw3215_info));

It suggests that this path was never executed. The code uses both
raw->cdev and raw->inbuf all over. And it is NULL due to the memset
here, so it would panic immediately. I believe nobody used that driver
without being a system console.

Either way, let us fix it by moving the allocations (and
initializations) to a single place. This will save us some double
initializations later too.

And while at it, initialize the timer properly -- once, at the
allocation.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby 2012-04-02 13:54:08 +02:00 committed by Greg Kroah-Hartman
parent 9f8c0b081d
commit fe2fc9ca5d
1 changed files with 39 additions and 35 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

74
drivers/s390/char/con3215.c
View File

@ -324,10 +324,7 @@ static inline void raw3215_try_io(struct raw3215_info *raw)
}
} else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
/* delay small writes */
init_timer(&raw->timer);
raw->timer.expires = RAW3215_TIMEOUT + jiffies;
raw->timer.data = (unsigned long) raw;
raw->timer.function = raw3215_timeout;
add_timer(&raw->timer);
raw->flags |= RAW3215_TIMER_RUNS;
}
@ -648,6 +645,35 @@ static void raw3215_shutdown(struct raw3215_info *raw)
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
static struct raw3215_info *raw3215_alloc_info(void)
{
struct raw3215_info *info;
info = kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA);
if (!info)
return NULL;
info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA);
if (!info->buffer || !info->inbuf) {
kfree(info);
return NULL;
}
setup_timer(&info->timer, raw3215_timeout, (unsigned long)info);
init_waitqueue_head(&info->empty_wait);
tasklet_init(&info->tlet, raw3215_wakeup, (unsigned long)info);
return info;
}
static void raw3215_free_info(struct raw3215_info *raw)
{
kfree(raw->inbuf);
kfree(raw->buffer);
kfree(raw);
}
static int raw3215_probe (struct ccw_device *cdev)
{
struct raw3215_info *raw;
@ -656,11 +682,15 @@ static int raw3215_probe (struct ccw_device *cdev)
/* Console is special. */
if (raw3215[0] && (raw3215[0] == dev_get_drvdata(&cdev->dev)))
return 0;
raw = kmalloc(sizeof(struct raw3215_info) +
RAW3215_INBUF_SIZE, GFP_KERNEL|GFP_DMA);
raw = raw3215_alloc_info();
if (raw == NULL)
return -ENOMEM;
raw->cdev = cdev;
dev_set_drvdata(&cdev->dev, raw);
cdev->handler = raw3215_irq;
spin_lock(&raw3215_device_lock);
for (line = 0; line < NR_3215; line++) {
if (!raw3215[line]) {
@ -670,28 +700,10 @@ static int raw3215_probe (struct ccw_device *cdev)
}
spin_unlock(&raw3215_device_lock);
if (line == NR_3215) {
kfree(raw);
raw3215_free_info(raw);
return -ENODEV;
}
raw->cdev = cdev;
raw->inbuf = (char *) raw + sizeof(struct raw3215_info);
memset(raw, 0, sizeof(struct raw3215_info));
raw->buffer = kmalloc(RAW3215_BUFFER_SIZE,
GFP_KERNEL|GFP_DMA);
if (raw->buffer == NULL) {
spin_lock(&raw3215_device_lock);
raw3215[line] = NULL;
spin_unlock(&raw3215_device_lock);
kfree(raw);
return -ENOMEM;
}
init_waitqueue_head(&raw->empty_wait);
tasklet_init(&raw->tlet, raw3215_wakeup, (unsigned long) raw);
dev_set_drvdata(&cdev->dev, raw);
cdev->handler = raw3215_irq;
return 0;
}
@ -703,8 +715,7 @@ static void raw3215_remove (struct ccw_device *cdev)
raw = dev_get_drvdata(&cdev->dev);
if (raw) {
dev_set_drvdata(&cdev->dev, NULL);
kfree(raw->buffer);
kfree(raw);
raw3215_free_info(raw);
}
}
@ -897,23 +908,16 @@ static int __init con3215_init(void)
if (IS_ERR(cdev))
return -ENODEV;
raw3215[0] = raw = (struct raw3215_info *)
kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA);
raw->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
raw->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA);
raw3215[0] = raw = raw3215_alloc_info();
raw->cdev = cdev;
dev_set_drvdata(&cdev->dev, raw);
cdev->handler = raw3215_irq;
raw->flags |= RAW3215_FIXED;
init_waitqueue_head(&raw->empty_wait);
tasklet_init(&raw->tlet, raw3215_wakeup, (unsigned long) raw);
/* Request the console irq */
if (raw3215_startup(raw) != 0) {
kfree(raw->inbuf);
kfree(raw->buffer);
kfree(raw);
raw3215_free_info(raw);
raw3215[0] = NULL;
return -ENODEV;
}