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Subject[PATCH 24/69] TTY: con3215, centralize allocation
Date
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>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
---
drivers/s390/char/con3215.c | 74 +++++++++++++++++++++++--------------------
1 file changed, 39 insertions(+), 35 deletions(-)

diff --git a/drivers/s390/char/con3215.c b/drivers/s390/char/con3215.c
index 4f9f1dc..7e30f85 100644
--- a/drivers/s390/char/con3215.c
+++ b/drivers/s390/char/con3215.c
@@ -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;
}
--
1.7.9.2



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