adv_pci_dio: Protect access to counter subdevice with a spin lock.

diff --git a/comedi/drivers/adv_pci_dio.c b/comedi/drivers/adv_pci_dio.c
index d793f6501fb488d8d9531151322bb1389775d3c9..19bf31eadf31a4f2478be0bf1cf5ffc54d5cfa57 100644 (file)
--- a/comedi/drivers/adv_pci_dio.c
+++ b/comedi/drivers/adv_pci_dio.c
@@ -471,12 +471,15 @@ static int pci_8254_insn_read(comedi_device * dev, comedi_subdevice * s,
 {
        const diosubd_data *d = (const diosubd_data *)s->private;
        unsigned int chan, chip, chipchan;
+       unsigned long flags;
 
        chan = CR_CHAN(insn->chanspec); /* channel on subdevice */
        chip = chan / 3;                /* chip on subdevice */
        chipchan = chan - (3 * chip);   /* channel on chip on subdevice */
+       comedi_spin_lock_irqsave(&s->spin_lock, flags);
        data[0] = i8254_read(dev->iobase + d->addr + (SIZE_8254 * chip),
                        0, chipchan);
+       comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
        return 1;
 }
 
@@ -488,12 +491,15 @@ static int pci_8254_insn_write(comedi_device * dev, comedi_subdevice * s,
 {
        const diosubd_data *d = (const diosubd_data *)s->private;
        unsigned int chan, chip, chipchan;
+       unsigned long flags;
 
        chan = CR_CHAN(insn->chanspec); /* channel on subdevice */
        chip = chan / 3;                /* chip on subdevice */
        chipchan = chan - (3 * chip);   /* channel on chip on subdevice */
+       comedi_spin_lock_irqsave(&s->spin_lock, flags);
        i8254_write(dev->iobase + d->addr + (SIZE_8254 * chip),
                        0, chipchan, data[0]);
+       comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
        return 1;
 }
 
@@ -506,26 +512,29 @@ static int pci_8254_insn_config(comedi_device * dev, comedi_subdevice * s,
        const diosubd_data *d = (const diosubd_data *)s->private;
        unsigned int chan, chip, chipchan;
        unsigned long iobase;
-       int ret;
+       int ret = 0;
+       unsigned long flags;
 
        chan = CR_CHAN(insn->chanspec); /* channel on subdevice */
        chip = chan / 3;                /* chip on subdevice */
        chipchan = chan - (3 * chip);   /* channel on chip on subdevice */
        iobase = dev->iobase + d->addr + (SIZE_8254 * chip);
+       comedi_spin_lock_irqsave(&s->spin_lock, flags);
        switch (data[0]) {
        case INSN_CONFIG_SET_COUNTER_MODE:
                ret = i8254_set_mode(iobase, 0, chipchan, data[1]);
                if (ret < 0)
-                       return -EINVAL;
+                       ret = -EINVAL;
                break;
        case INSN_CONFIG_8254_READ_STATUS:
                data[1] = i8254_status(iobase, 0, chipchan);
                break;
        default:
-               return -EINVAL;
+               ret = -EINVAL;
                break;
        }
-       return insn->n;
+       comedi_spin_unlock_irqrestore(&s->spin_lock, flags);
+       return ret < 0 ? ret : insn->n;
 }
 
 /*