/* only allow one open process at a time to open each channel */
static int rtlx_open(struct inode *inode, struct file *filp)
{
int minor, ret;
struct rtlx_channel *chan;
/* assume only 1 device at the mo. */
minor = MINOR(inode->i_rdev);
if (rtlx == NULL) {
struct rtlx_info **p;
if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
printk(KERN_ERR "vpe_get_shared is NULL. "
"Has an SP program been loaded?\n");
return -EFAULT;
}
if (*p == NULL) {
printk(KERN_ERR "vpe_shared %p %p\n", p, *p);
return -EFAULT;
}
if ((ret = rtlx_init(*p)) < 0)
return ret;
}
chan = &rtlx->channel[minor];
if (test_and_set_bit(RTLX_STATE_OPENED, &chan->lx_state))
return -EBUSY;
return 0;
}
/* only allow one open process at a time to open each channel */
static int rtlx_open(struct inode *inode, struct file *filp)
{
int minor, ret;
struct rtlx_channel *chan;
/* assume only 1 device at the mo. */
minor = MINOR(inode->i_rdev);
if (rtlx == NULL) {
struct rtlx_info **p;
if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
printk(" vpe_get_shared is NULL. Has an SP program been loaded?\n");
return (-EFAULT);
}
if (*p == NULL) {
printk(" vpe_shared %p %p\n", p, *p);
return (-EFAULT);
}
if ((ret = rtlx_init(*p)) < 0)
return (ret);
}
chan = &rtlx->channel[minor];
/* already open? */
if (chan->lx_state == RTLX_STATE_OPENED)
return (-EBUSY);
chan->lx_state = RTLX_STATE_OPENED;
return (0);
}
static void rtlx_interrupt(void)
{
int i;
struct rtlx_info *info;
struct rtlx_info **p = vpe_get_shared(aprp_cpu_index());
if (p == NULL || *p == NULL)
return;
info = *p;
if (info->ap_int_pending == 1 && smp_processor_id() == 0) {
for (i = 0; i < RTLX_CHANNELS; i++) {
wake_up(&channel_wqs[i].lx_queue);
wake_up(&channel_wqs[i].rt_queue);
}
info->ap_int_pending = 0;
}
}
int rtlx_open(int index, int can_sleep)
{
struct rtlx_info **p;
struct rtlx_channel *chan;
enum rtlx_state state;
int ret = 0;
if (index >= RTLX_CHANNELS) {
printk(KERN_DEBUG "rtlx_open index out of range\n");
return -ENOSYS;
}
if (atomic_inc_return(&channel_wqs[index].in_open) > 1) {
printk(KERN_DEBUG "rtlx_open channel %d already opened\n",
index);
ret = -EBUSY;
goto out_fail;
}
if (rtlx == NULL) {
if( (p = vpe_get_shared(tclimit)) == NULL) {
if (can_sleep) {
__wait_event_interruptible(channel_wqs[index].lx_queue,
(p = vpe_get_shared(tclimit)), ret);
if (ret)
goto out_fail;
} else {
printk(KERN_DEBUG "No SP program loaded, and device "
"opened with O_NONBLOCK\n");
ret = -ENOSYS;
goto out_fail;
}
}
smp_rmb();
if (*p == NULL) {
if (can_sleep) {
DEFINE_WAIT(wait);
for (;;) {
prepare_to_wait(
&channel_wqs[index].lx_queue,
&wait, TASK_INTERRUPTIBLE);
smp_rmb();
if (*p != NULL)
break;
if (!signal_pending(current)) {
schedule();
continue;
}
ret = -ERESTARTSYS;
goto out_fail;
}
finish_wait(&channel_wqs[index].lx_queue, &wait);
} else {
pr_err(" *vpe_get_shared is NULL. "
"Has an SP program been loaded?\n");
ret = -ENOSYS;
goto out_fail;
}
}
if ((unsigned int)*p < KSEG0) {
printk(KERN_WARNING "vpe_get_shared returned an "
"invalid pointer maybe an error code %d\n",
(int)*p);
ret = -ENOSYS;
goto out_fail;
}
if ((ret = rtlx_init(*p)) < 0)
goto out_ret;
}
chan = &rtlx->channel[index];
state = xchg(&chan->lx_state, RTLX_STATE_OPENED);
if (state == RTLX_STATE_OPENED) {
ret = -EBUSY;
goto out_fail;
}
out_fail:
smp_mb();
atomic_dec(&channel_wqs[index].in_open);
smp_mb();
out_ret:
return ret;
}
int rtlx_open(int index, int can_sleep)
{
int ret;
struct rtlx_channel *chan;
volatile struct rtlx_info **p;
if (index >= RTLX_CHANNELS) {
printk(KERN_DEBUG "rtlx_open index out of range\n");
return -ENOSYS;
}
if (channel_wqs[index].in_open) {
printk(KERN_DEBUG "rtlx_open channel %d already opened\n", index);
return -EBUSY;
}
channel_wqs[index].in_open++;
if (rtlx == NULL) {
if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
if (can_sleep) {
DECLARE_WAITQUEUE(wait, current);
/* go to sleep */
add_wait_queue(&channel_wqs[index].lx_queue, &wait);
set_current_state(TASK_INTERRUPTIBLE);
while ((p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
schedule();
set_current_state(TASK_INTERRUPTIBLE);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
/* back running */
} else {
printk( KERN_DEBUG "No SP program loaded, and device "
"opened with O_NONBLOCK\n");
channel_wqs[index].in_open = 0;
return -ENOSYS;
}
}
if (*p == NULL) {
if (can_sleep) {
DECLARE_WAITQUEUE(wait, current);
/* go to sleep */
add_wait_queue(&channel_wqs[index].lx_queue, &wait);
set_current_state(TASK_INTERRUPTIBLE);
while (*p == NULL) {
schedule();
/* reset task state to interruptable otherwise
we'll whizz round here like a very fast loopy
thing. schedule() appears to return with state
set to TASK_RUNNING.
If the loaded SP program, for whatever reason,
doesn't set up the shared structure *p will never
become true. So whoever connected to either /dev/rt?
or if it was kspd, will then take up rather a lot of
processor cycles.
*/
set_current_state(TASK_INTERRUPTIBLE);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
/* back running */
}
else {
printk(" *vpe_get_shared is NULL. "
"Has an SP program been loaded?\n");
channel_wqs[index].in_open = 0;
return -ENOSYS;
}
}
if ((unsigned int)*p < KSEG0) {
printk(KERN_WARNING "vpe_get_shared returned an invalid pointer "
"maybe an error code %d\n", (int)*p);
channel_wqs[index].in_open = 0;
return -ENOSYS;
}
if ((ret = rtlx_init(*p)) < 0) {
channel_wqs[index].in_open = 0;
return ret;
}
}
chan = &rtlx->channel[index];
if (chan->lx_state == RTLX_STATE_OPENED) {
channel_wqs[index].in_open = 0;
return -EBUSY;
}
chan->lx_state = RTLX_STATE_OPENED;
channel_wqs[index].in_open = 0;
return 0;
}
int rtlx_open(int index, int can_sleep)
{
volatile struct rtlx_info **p;
struct rtlx_channel *chan;
enum rtlx_state state;
int ret = 0;
if (index >= RTLX_CHANNELS) {
printk(KERN_DEBUG "rtlx_open index out of range\n");
return -ENOSYS;
}
if (atomic_inc_return(&channel_wqs[index].in_open) > 1) {
printk(KERN_DEBUG "rtlx_open channel %d already opened\n",
index);
ret = -EBUSY;
goto out_fail;
}
if (rtlx == NULL) {
if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
if (can_sleep) {
__wait_event_interruptible(channel_wqs[index].lx_queue,
(p = vpe_get_shared(RTLX_TARG_VPE)),
ret);
if (ret)
goto out_fail;
} else {
printk(KERN_DEBUG "No SP program loaded, and device "
"opened with O_NONBLOCK\n");
ret = -ENOSYS;
goto out_fail;
}
}
if (*p == NULL) {
if (can_sleep) {
__wait_event_interruptible(channel_wqs[index].lx_queue,
*p != NULL,
ret);
if (ret)
goto out_fail;
} else {
printk(" *vpe_get_shared is NULL. "
"Has an SP program been loaded?\n");
ret = -ENOSYS;
goto out_fail;
}
}
if ((unsigned int)*p < KSEG0) {
printk(KERN_WARNING "vpe_get_shared returned an invalid pointer "
"maybe an error code %d\n", (int)*p);
ret = -ENOSYS;
goto out_fail;
}
if ((ret = rtlx_init(*p)) < 0)
goto out_ret;
}
chan = &rtlx->channel[index];
state = xchg(&chan->lx_state, RTLX_STATE_OPENED);
if (state == RTLX_STATE_OPENED) {
ret = -EBUSY;
goto out_fail;
}
out_fail:
smp_mb();
atomic_dec(&channel_wqs[index].in_open);
smp_mb();
out_ret:
return ret;
}
