#include <linux/pg.h>
#include <linux/device.h>
#include <linux/sched.h> /* current, TASK_* */
+#include <linux/smp_lock.h>
#include <linux/jiffies.h>
#include <asm/uaccess.h>
{
int unit = iminor(inode) & 0x7f;
struct pg *dev = &devices[unit];
+ int ret = 0;
- if ((unit >= PG_UNITS) || (!dev->present))
- return -ENODEV;
+ lock_kernel();
+ if ((unit >= PG_UNITS) || (!dev->present)) {
+ ret = -ENODEV;
+ goto out;
+ }
- if (test_and_set_bit(0, &dev->access))
- return -EBUSY;
+ if (test_and_set_bit(0, &dev->access)) {
+ ret = -EBUSY;
+ goto out;
+ }
if (dev->busy) {
pg_reset(dev);
if (dev->bufptr == NULL) {
clear_bit(0, &dev->access);
printk("%s: buffer allocation failed\n", dev->name);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out;
}
file->private_data = dev;
- return 0;
+out:
+ unlock_kernel();
+ return ret;
}
static int pg_release(struct inode *inode, struct file *file)
#include <linux/mtio.h>
#include <linux/device.h>
#include <linux/sched.h> /* current, TASK_*, schedule_timeout() */
+#include <linux/smp_lock.h>
#include <asm/uaccess.h>
struct pt_unit *tape = pt + unit;
int err;
- if (unit >= PT_UNITS || (!tape->present))
+ lock_kernel();
+ if (unit >= PT_UNITS || (!tape->present)) {
+ unlock_kernel();
return -ENODEV;
+ }
err = -EBUSY;
if (!atomic_dec_and_test(&tape->available))
}
file->private_data = tape;
+ unlock_kernel();
return 0;
out:
atomic_inc(&tape->available);
+ unlock_kernel();
return err;
}