Commit 085e5676 authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Martin K. Petersen
Browse files

scsi: ch: add refcounting 



struct scsi_changer needs refcounting as the device might be removed
while the fd is still open.

[mkp: whitespace]

Signed-off-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent db269932

drivers/scsi/ch.c

+19 −3
Original line number Diff line number Diff line
@@ -105,6 +105,7 @@ do { \ 
static struct class * ch_sysfs_class;



typedef struct {

	struct kref         ref;

	struct list_head    list;

	int                 minor;

	char                name[8];
@@ -563,13 +564,23 @@ static int ch_gstatus(scsi_changer *ch, int type, unsigned char __user *dest) 


/* ------------------------------------------------------------------------ */



static void ch_destroy(struct kref *ref)

{

	scsi_changer *ch = container_of(ref, scsi_changer, ref);



	kfree(ch->dt);

	kfree(ch);

}



static int

ch_release(struct inode *inode, struct file *file)

{

	scsi_changer *ch = file->private_data;



	scsi_device_put(ch->device);

	ch->device = NULL;

	file->private_data = NULL;

	kref_put(&ch->ref, ch_destroy);

	return 0;

}
@@ -588,6 +599,7 @@ ch_open(struct inode *inode, struct file *file) 
		mutex_unlock(&ch_mutex);

		return -ENXIO;

	}

	kref_get(&ch->ref);

	spin_unlock(&ch_index_lock);



	file->private_data = ch;
@@ -935,8 +947,11 @@ static int ch_probe(struct device *dev) 
	}



	mutex_init(&ch->lock);

	kref_init(&ch->ref);

	ch->device = sd;

	ch_readconfig(ch);

	ret = ch_readconfig(ch);

	if (ret)

		goto destroy_dev;

	if (init)

		ch_init_elem(ch);
@@ -944,6 +959,8 @@ static int ch_probe(struct device *dev) 
	sdev_printk(KERN_INFO, sd, "Attached scsi changer %s\n", ch->name);



	return 0;

destroy_dev:

	device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR, ch->minor));

remove_idr:

	idr_remove(&ch_index_idr, ch->minor);

free_ch:
@@ -960,8 +977,7 @@ static int ch_remove(struct device *dev) 
	spin_unlock(&ch_index_lock);



	device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR,ch->minor));

	kfree(ch->dt);

	kfree(ch);

	kref_put(&ch->ref, ch_destroy);

	return 0;

}