Commit 8fd138c3 authored by Martin Schwidefsky's avatar Martin Schwidefsky Committed by Martin Schwidefsky

[S390] tape: cleanup reference counting

Rename tape_get_device to tape_find_device and tape_get_device_reference
to tape_get_device. The old names didn't make too much sense.

Follow the get_device()/put_device() semantic and convert tape_put_device
to a void function.
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 1b52fff0
......@@ -292,9 +292,9 @@ extern int tape_generic_pm_suspend(struct ccw_device *);
extern int tape_generic_probe(struct ccw_device *);
extern void tape_generic_remove(struct ccw_device *);
extern struct tape_device *tape_get_device(int devindex);
extern struct tape_device *tape_get_device_reference(struct tape_device *);
extern struct tape_device *tape_put_device(struct tape_device *);
extern struct tape_device *tape_find_device(int devindex);
extern struct tape_device *tape_get_device(struct tape_device *);
extern void tape_put_device(struct tape_device *);
/* Externals from tape_char.c */
extern int tapechar_init(void);
......
......@@ -113,16 +113,16 @@ tape_34xx_work_handler(struct work_struct *work)
{
struct tape_34xx_work *p =
container_of(work, struct tape_34xx_work, work);
struct tape_device *device = p->device;
switch(p->op) {
case TO_MSEN:
tape_34xx_medium_sense(p->device);
tape_34xx_medium_sense(device);
break;
default:
DBF_EVENT(3, "T34XX: internal error: unknown work\n");
}
p->device = tape_put_device(p->device);
tape_put_device(device);
kfree(p);
}
......@@ -136,7 +136,7 @@ tape_34xx_schedule_work(struct tape_device *device, enum tape_op op)
INIT_WORK(&p->work, tape_34xx_work_handler);
p->device = tape_get_device_reference(device);
p->device = tape_get_device(device);
p->op = op;
schedule_work(&p->work);
......
......@@ -608,7 +608,7 @@ tape_3590_schedule_work(struct tape_device *device, enum tape_op op)
INIT_WORK(&p->work, tape_3590_work_handler);
p->device = tape_get_device_reference(device);
p->device = tape_get_device(device);
p->op = op;
schedule_work(&p->work);
......
......@@ -239,7 +239,7 @@ tapeblock_setup_device(struct tape_device * device)
disk->major = tapeblock_major;
disk->first_minor = device->first_minor;
disk->fops = &tapeblock_fops;
disk->private_data = tape_get_device_reference(device);
disk->private_data = tape_get_device(device);
disk->queue = blkdat->request_queue;
set_capacity(disk, 0);
sprintf(disk->disk_name, "btibm%d",
......@@ -247,11 +247,11 @@ tapeblock_setup_device(struct tape_device * device)
blkdat->disk = disk;
blkdat->medium_changed = 1;
blkdat->request_queue->queuedata = tape_get_device_reference(device);
blkdat->request_queue->queuedata = tape_get_device(device);
add_disk(disk);
tape_get_device_reference(device);
tape_get_device(device);
INIT_WORK(&blkdat->requeue_task, tapeblock_requeue);
return 0;
......@@ -274,13 +274,14 @@ tapeblock_cleanup_device(struct tape_device *device)
}
del_gendisk(device->blk_data.disk);
device->blk_data.disk->private_data =
tape_put_device(device->blk_data.disk->private_data);
device->blk_data.disk->private_data = NULL;
tape_put_device(device);
put_disk(device->blk_data.disk);
device->blk_data.disk = NULL;
cleanup_queue:
device->blk_data.request_queue->queuedata = tape_put_device(device);
device->blk_data.request_queue->queuedata = NULL;
tape_put_device(device);
blk_cleanup_queue(device->blk_data.request_queue);
device->blk_data.request_queue = NULL;
......@@ -363,7 +364,7 @@ tapeblock_open(struct block_device *bdev, fmode_t mode)
struct tape_device * device;
int rc;
device = tape_get_device_reference(disk->private_data);
device = tape_get_device(disk->private_data);
if (device->required_tapemarks) {
DBF_EVENT(2, "TBLOCK: missing tapemarks\n");
......
......@@ -286,9 +286,9 @@ tapechar_open (struct inode *inode, struct file *filp)
lock_kernel();
minor = iminor(filp->f_path.dentry->d_inode);
device = tape_get_device(minor / TAPE_MINORS_PER_DEV);
device = tape_find_device(minor / TAPE_MINORS_PER_DEV);
if (IS_ERR(device)) {
DBF_EVENT(3, "TCHAR:open: tape_get_device() failed\n");
DBF_EVENT(3, "TCHAR:open: tape_find_device() failed\n");
rc = PTR_ERR(device);
goto out;
}
......@@ -340,7 +340,8 @@ tapechar_release(struct inode *inode, struct file *filp)
device->char_data.idal_buf = NULL;
}
tape_release(device);
filp->private_data = tape_put_device(device);
filp->private_data = NULL;
tape_put_device(device);
return 0;
}
......
......@@ -511,11 +511,12 @@ tape_alloc_device(void)
* increment the reference count.
*/
struct tape_device *
tape_get_device_reference(struct tape_device *device)
tape_get_device(struct tape_device *device)
{
DBF_EVENT(4, "tape_get_device_reference(%p) = %i\n", device,
atomic_inc_return(&device->ref_count));
int count;
count = atomic_inc_return(&device->ref_count);
DBF_EVENT(4, "tape_get_device(%p) = %i\n", device, count);
return device;
}
......@@ -525,32 +526,25 @@ tape_get_device_reference(struct tape_device *device)
* The function returns a NULL pointer to be used by the caller
* for clearing reference pointers.
*/
struct tape_device *
void
tape_put_device(struct tape_device *device)
{
int remain;
int count;
remain = atomic_dec_return(&device->ref_count);
if (remain > 0) {
DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, remain);
} else {
if (remain < 0) {
DBF_EVENT(4, "put device without reference\n");
} else {
DBF_EVENT(4, "tape_free_device(%p)\n", device);
kfree(device->modeset_byte);
kfree(device);
}
count = atomic_dec_return(&device->ref_count);
DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, count);
BUG_ON(count < 0);
if (count == 0) {
kfree(device->modeset_byte);
kfree(device);
}
return NULL;
}
/*
* Find tape device by a device index.
*/
struct tape_device *
tape_get_device(int devindex)
tape_find_device(int devindex)
{
struct tape_device *device, *tmp;
......@@ -558,7 +552,7 @@ tape_get_device(int devindex)
read_lock(&tape_device_lock);
list_for_each_entry(tmp, &tape_device_list, node) {
if (tmp->first_minor / TAPE_MINORS_PER_DEV == devindex) {
device = tape_get_device_reference(tmp);
device = tape_get_device(tmp);
break;
}
}
......@@ -607,7 +601,8 @@ __tape_discard_requests(struct tape_device *device)
list_del(&request->list);
/* Decrease ref_count for removed request. */
request->device = tape_put_device(device);
request->device = NULL;
tape_put_device(device);
request->rc = -EIO;
if (request->callback != NULL)
request->callback(request, request->callback_data);
......@@ -665,9 +660,11 @@ tape_generic_remove(struct ccw_device *cdev)
tape_cleanup_device(device);
}
if (dev_get_drvdata(&cdev->dev)) {
device = dev_get_drvdata(&cdev->dev);
if (device) {
sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group);
dev_set_drvdata(&cdev->dev, tape_put_device(dev_get_drvdata(&cdev->dev)));
dev_set_drvdata(&cdev->dev, NULL);
tape_put_device(device);
}
}
......@@ -722,9 +719,8 @@ tape_free_request (struct tape_request * request)
{
DBF_LH(6, "Free request %p\n", request);
if (request->device != NULL) {
request->device = tape_put_device(request->device);
}
if (request->device)
tape_put_device(request->device);
kfree(request->cpdata);
kfree(request->cpaddr);
kfree(request);
......@@ -839,7 +835,8 @@ static void tape_long_busy_timeout(unsigned long data)
BUG_ON(request->status != TAPE_REQUEST_LONG_BUSY);
DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id);
__tape_start_next_request(device);
device->lb_timeout.data = (unsigned long) tape_put_device(device);
device->lb_timeout.data = 0UL;
tape_put_device(device);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
}
......@@ -919,7 +916,7 @@ __tape_start_request(struct tape_device *device, struct tape_request *request)
}
/* Increase use count of device for the added request. */
request->device = tape_get_device_reference(device);
request->device = tape_get_device(device);
if (list_empty(&device->req_queue)) {
/* No other requests are on the queue. Start this one. */
......@@ -1118,8 +1115,8 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
if (req->status == TAPE_REQUEST_LONG_BUSY) {
DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id);
if (del_timer(&device->lb_timeout)) {
device->lb_timeout.data = (unsigned long)
tape_put_device(device);
device->lb_timeout.data = 0UL;
tape_put_device(device);
__tape_start_next_request(device);
}
return;
......@@ -1174,7 +1171,7 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
break;
case TAPE_IO_LONG_BUSY:
device->lb_timeout.data =
(unsigned long)tape_get_device_reference(device);
(unsigned long) tape_get_device(device);
device->lb_timeout.expires = jiffies +
LONG_BUSY_TIMEOUT * HZ;
DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id);
......@@ -1327,7 +1324,7 @@ EXPORT_SYMBOL(tape_generic_online);
EXPORT_SYMBOL(tape_generic_offline);
EXPORT_SYMBOL(tape_generic_pm_suspend);
EXPORT_SYMBOL(tape_put_device);
EXPORT_SYMBOL(tape_get_device_reference);
EXPORT_SYMBOL(tape_get_device);
EXPORT_SYMBOL(tape_state_verbose);
EXPORT_SYMBOL(tape_op_verbose);
EXPORT_SYMBOL(tape_state_set);
......
......@@ -45,7 +45,7 @@ static int tape_proc_show(struct seq_file *m, void *v)
seq_printf(m, "TapeNo\tBusID CuType/Model\t"
"DevType/Model\tBlkSize\tState\tOp\tMedState\n");
}
device = tape_get_device(n);
device = tape_find_device(n);
if (IS_ERR(device))
return 0;
spin_lock_irq(get_ccwdev_lock(device->cdev));
......
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