unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
{
struct cxl_context *ctx = file->private_data;
int mask = 0;
unsigned long flags;
poll_wait(file, &ctx->wq, poll);
pr_devel("afu_poll wait done pe: %i\n", ctx->pe);
spin_lock_irqsave(&ctx->lock, flags);
if (ctx_event_pending(ctx))
mask |= POLLIN | POLLRDNORM;
else if (ctx->status == CLOSED)
/* Only error on closed when there are no futher events pending
*/
mask |= POLLERR;
spin_unlock_irqrestore(&ctx->lock, flags);
pr_devel("afu_poll pe: %i returning %#x\n", ctx->pe, mask);
return mask;
}
static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
loff_t *off)
{
struct cxl_context *ctx = file->private_data;
struct cxl_event event;
unsigned long flags;
int rc;
DEFINE_WAIT(wait);
if (count < CXL_READ_MIN_SIZE)
return -EINVAL;
spin_lock_irqsave(&ctx->lock, flags);
for (;;) {
prepare_to_wait(&ctx->wq, &wait, TASK_INTERRUPTIBLE);
if (ctx_event_pending(ctx))
break;
if (file->f_flags & O_NONBLOCK) {
rc = -EAGAIN;
goto out;
}
if (signal_pending(current)) {
rc = -ERESTARTSYS;
goto out;
}
spin_unlock_irqrestore(&ctx->lock, flags);
pr_devel("afu_read going to sleep...\n");
schedule();
pr_devel("afu_read woken up\n");
spin_lock_irqsave(&ctx->lock, flags);
}
finish_wait(&ctx->wq, &wait);
memset(&event, 0, sizeof(event));
event.header.process_element = ctx->pe;
event.header.size = sizeof(struct cxl_event_header);
if (ctx->pending_irq) {
pr_devel("afu_read delivering AFU interrupt\n");
event.header.size += sizeof(struct cxl_event_afu_interrupt);
event.header.type = CXL_EVENT_AFU_INTERRUPT;
event.irq.irq = find_first_bit(ctx->irq_bitmap, ctx->irq_count) + 1;
clear_bit(event.irq.irq - 1, ctx->irq_bitmap);
if (bitmap_empty(ctx->irq_bitmap, ctx->irq_count))
ctx->pending_irq = false;
} else if (ctx->pending_fault) {
pr_devel("afu_read delivering data storage fault\n");
event.header.size += sizeof(struct cxl_event_data_storage);
event.header.type = CXL_EVENT_DATA_STORAGE;
event.fault.addr = ctx->fault_addr;
event.fault.dsisr = ctx->fault_dsisr;
ctx->pending_fault = false;
} else if (ctx->pending_afu_err) {
pr_devel("afu_read delivering afu error\n");
event.header.size += sizeof(struct cxl_event_afu_error);
event.header.type = CXL_EVENT_AFU_ERROR;
event.afu_error.error = ctx->afu_err;
ctx->pending_afu_err = false;
} else if (ctx->status == CLOSED) {
pr_devel("afu_read fatal error\n");
spin_unlock_irqrestore(&ctx->lock, flags);
return -EIO;
} else
WARN(1, "afu_read must be buggy\n");
spin_unlock_irqrestore(&ctx->lock, flags);
if (copy_to_user(buf, &event, event.header.size))
return -EFAULT;
return event.header.size;
out:
finish_wait(&ctx->wq, &wait);
spin_unlock_irqrestore(&ctx->lock, flags);
return rc;
}
