init gnumach copy

1 files changed, 372 insertions, 0 deletions

diff --git a/device/intr.c b/device/intr.c
new file mode 100644
index 0000000..9035c03
--- /dev/null
+++ b/device/intr.c
@@ -0,0 +1,372 @@
+/*
+ * Copyright (c) 2010, 2011, 2016, 2019 Free Software Foundation, Inc.
+ *
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * THE FREE SOFTWARE FOUNDATIONALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  THE FREE SOFTWARE FOUNDATION DISCLAIMS ANY LIABILITY OF ANY KIND
+ * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ */
+
+#include <kern/assert.h>
+#include <device/intr.h>
+#include <device/device_types.h>
+#include <device/device_port.h>
+#include <device/notify.h>
+#include <kern/printf.h>
+#include <machine/spl.h>
+#include <machine/irq.h>
+#include <ipc/ipc_space.h>
+
+#ifndef MACH_XEN
+
+queue_head_t main_intr_queue;
+static boolean_t deliver_intr (int id, ipc_port_t dst_port);
+
+#ifndef LINUX_DEV
+#define SA_SHIRQ 0x04000000
+
+struct intr_list {
+  user_intr_t *user_intr;
+  unsigned long flags;
+  struct intr_list *next;
+};
+static struct intr_list *user_intr_handlers[NINTR];
+#endif
+
+static user_intr_t *
+search_intr (struct irqdev *dev, ipc_port_t dst_port)
+{
+  user_intr_t *e;
+  queue_iterate (dev->intr_queue, e, user_intr_t *, chain)
+    {
+      if (e->dst_port == dst_port)
+	return e;
+    }
+  return NULL;
+}
+
+
+/*
+ * Interrupt handling logic:
+ *
+ * interrupt.S raises spl (thus IF cleared)
+ * interrupt.S EOI
+ * interrupt.S calls the handler
+ *   - for pure in-kernel handlers, they do whatever they want with IF cleared.
+ *   - when a userland handler is registered, queue_intr masks the irq.
+ * interrupt.S lowers spl with splx_cli, thus IF still cleared
+ * iret, that also sets IF
+ *
+ * later on, (irq_acknowledge), userland acks the IRQ, that unmasks the irq
+ */
+kern_return_t
+irq_acknowledge (ipc_port_t receive_port)
+{
+  user_intr_t *e;
+  kern_return_t ret = 0;
+
+  spl_t s = splhigh ();
+  e = search_intr (&irqtab, receive_port);
+
+  if (!e)
+    {
+      printf("didn't find user intr for interrupt !?\n");
+      ret = KERN_INVALID_ARGUMENT;
+    }
+  else
+    {
+      if (!e->n_unacked)
+        ret = D_INVALID_OPERATION;
+      else
+        e->n_unacked--;
+    }
+  splx (s);
+
+  if (ret)
+    return ret;
+
+  __enable_irq (irqtab.irq[e->id]);
+
+  return D_SUCCESS;
+}
+
+/* This function can only be used in the interrupt handler. */
+static void
+queue_intr (struct irqdev *dev, int id, user_intr_t *e)
+{
+  /* Until userland has handled the IRQ in the driver, we have to keep it
+   * disabled. Level-triggered interrupts would keep raising otherwise. */
+  __disable_irq (dev->irq[id]);
+
+  spl_t s = splhigh ();
+  e->n_unacked++;
+  e->interrupts++;
+  dev->tot_num_intr++;
+  splx (s);
+
+  thread_wakeup ((event_t) &intr_thread);
+}
+
+int
+deliver_user_intr (struct irqdev *dev, int id, user_intr_t *e)
+{
+  /* The reference of the port was increased
+   * when the port was installed.  If the reference is 1, it means
+   * the port was deallocated and we should clean after it. */
+  if (!e->dst_port || e->dst_port->ip_references == 1)
+    {
+      thread_wakeup ((event_t) &intr_thread);
+      return 0;
+    }
+  else
+    {
+      queue_intr (dev, id, e);
+      return 1;
+    }
+}
+
+/* insert an interrupt entry in the queue.
+ * This entry exists in the queue until
+ * the corresponding interrupt port is removed.*/
+user_intr_t *
+insert_intr_entry (struct irqdev *dev, int id, ipc_port_t dst_port)
+{
+  user_intr_t *e, *new, *ret;
+  int free = 0;
+
+  new = (user_intr_t *) kalloc (sizeof (*new));
+  if (new == NULL)
+    return NULL;
+
+  /* check whether the intr entry has been in the queue. */
+  spl_t s = splhigh ();
+  e = search_intr (dev, dst_port);
+  if (e)
+    {
+      printf ("the interrupt entry for irq[%d] and port %p has already been inserted\n", id, dst_port);
+      free = 1;
+      ret = NULL;
+      goto out;
+    }
+  printf("irq handler [%d]: new delivery port %p entry %p\n", id, dst_port, new);
+  ret = new;
+  new->id = id;
+  new->dst_port = dst_port;
+  new->interrupts = 0;
+  new->n_unacked = 0;
+
+  queue_enter (dev->intr_queue, new, user_intr_t *, chain);
+out:
+  splx (s);
+  if (free)
+    kfree ((vm_offset_t) new, sizeof (*new));
+  return ret;
+}
+
+#ifndef LINUX_DEV
+
+static void
+user_irq_handler (int id)
+{
+  struct intr_list *handler;
+  struct intr_list **prev = &user_intr_handlers[id];
+  user_intr_t *e;
+  spl_t s;
+
+  s = splhigh();
+
+  for (handler = *prev; handler; handler = handler->next)
+    {
+      e = handler->user_intr;
+      if (!deliver_user_intr(&irqtab, id, e))
+        {
+          /* We failed to deliver this interrupt, remove handler from list */
+	  *prev = handler->next;
+        }
+      prev = &handler->next;
+    }
+  splx(s);
+}
+
+int
+install_user_intr_handler (struct irqdev *dev, int id, unsigned long flags,
+			  user_intr_t *user_intr)
+{
+  unsigned int irq = dev->irq[id];
+  struct intr_list **head = &user_intr_handlers[id];
+  struct intr_list *new, *old = *head;
+  spl_t s;
+
+  flags |= SA_SHIRQ;
+
+  assert (irq < NINTR);
+
+  /* Don't allow overriding hardclock/kdintr etc */
+  if ((ivect[irq] != user_irq_handler) && (ivect[irq] != intnull))
+    {
+      printf("You can't have this interrupt\n");
+      return D_ALREADY_OPEN;
+    }
+
+  if (old)
+    {
+      if (!(old->flags & flags & SA_SHIRQ))
+        {
+          printf ("Cannot share irq\n");
+          return D_ALREADY_OPEN;
+        }
+    }
+
+  new = (struct intr_list *)kalloc (sizeof (struct intr_list));
+  new->user_intr = user_intr;
+  new->flags = flags;
+
+  s = splhigh();
+  new->next = *head;
+  *head = new;
+  ivect[irq] = user_irq_handler;
+  iunit[irq] = (int)irq;
+  unmask_irq (irq);
+  splx(s);
+
+  return D_SUCCESS;
+}
+#endif
+
+void
+intr_thread (void)
+{
+  user_intr_t *e;
+  int id;
+  ipc_port_t dst_port;
+  queue_init (&main_intr_queue);
+
+  for (;;)
+    {
+      assert_wait ((event_t) &intr_thread, FALSE);
+      /* Make sure we wake up from times to times to check for aborted processes */
+      thread_set_timeout (hz);
+      spl_t s = splhigh ();
+
+      /* Now check for interrupts */
+      int del;
+      do
+	{
+	  del = 0;
+
+	  queue_iterate (&main_intr_queue, e, user_intr_t *, chain)
+	    {
+	      /* The reference of the port was increased
+               * when the port was installed.  If the reference is 1, it means
+               * the port was deallocated and we should clean after it. */
+	      if (e->dst_port->ip_references == 1)
+		{
+		  clear_wait (current_thread (), 0, 0);
+		  del = 1;
+		  break;
+		}
+
+	      if (e->interrupts)
+		{
+		  clear_wait (current_thread (), 0, 0);
+		  id = e->id;
+		  dst_port = e->dst_port;
+		  e->interrupts--;
+		  irqtab.tot_num_intr--;
+
+		  splx (s);
+		  deliver_intr (id, dst_port);
+		  s = splhigh ();
+		}
+	    }
+
+	  /* remove the entry without dest port from the queue and free it. */
+	  if (del)
+	    {
+	      /*
+	       * We clear unacked irqs now, so the Linux handling can trigger,
+	       * and we will cleanup later after the Linux handler is cleared.
+	       */
+	      assert (!queue_empty (&main_intr_queue));
+	      queue_remove (&main_intr_queue, e, user_intr_t *, chain);
+
+	      printf ("irq handler [%d]: release a dead delivery port %p entry %p\n", e->id, e->dst_port, e);
+	      ipc_port_release (e->dst_port);
+	      e->dst_port = MACH_PORT_NULL;
+
+	      if (e->n_unacked)
+		printf("irq handler [%d]: still %d unacked irqs in entry %p\n", e->id, e->n_unacked, e);
+	      while (e->n_unacked)
+	      {
+		__enable_irq (irqtab.irq[e->id]);
+		e->n_unacked--;
+	      }
+
+#if 0
+#ifndef LINUX_DEV
+	      // TODO: remove from the action list
+#else
+	      // FIXME: with the Linux irq handler we don't actually control the action list
+#endif
+	      splx (s);
+	      kfree ((vm_offset_t) e, sizeof (*e));
+	      s = splhigh ();
+#endif
+	    }
+	}
+      while (del || irqtab.tot_num_intr);
+      splx (s);
+      thread_block (NULL);
+    }
+}
+
+static boolean_t
+deliver_intr (int id, ipc_port_t dst_port)
+{
+  ipc_kmsg_t kmsg;
+  device_intr_notification_t *n;
+  mach_port_t dest = (mach_port_t) dst_port;
+
+  if (dest == MACH_PORT_NULL)
+    return FALSE;
+
+  kmsg = ikm_alloc(sizeof *n);
+  if (kmsg == IKM_NULL)
+    return FALSE;
+
+  ikm_init(kmsg, sizeof *n);
+  n = (device_intr_notification_t *) &kmsg->ikm_header;
+
+  mach_msg_header_t *m = &n->intr_header;
+  mach_msg_type_t *t = &n->intr_type;
+
+  m->msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0);
+  m->msgh_size = sizeof *n;
+  m->msgh_seqno = DEVICE_NOTIFY_MSGH_SEQNO;
+  m->msgh_local_port = MACH_PORT_NULL;
+  m->msgh_remote_port = MACH_PORT_NULL;
+  m->msgh_id = DEVICE_INTR_NOTIFY;
+
+  t->msgt_name = MACH_MSG_TYPE_INTEGER_32;
+  t->msgt_size = 32;
+  t->msgt_number = 1;
+  t->msgt_inline = TRUE;
+  t->msgt_longform = FALSE;
+  t->msgt_deallocate = FALSE;
+  t->msgt_unused = 0;
+
+  n->intr_header.msgh_remote_port = dest;
+  n->id = id;
+
+  ipc_port_copy_send (dst_port);
+  ipc_mqueue_send_always(kmsg);
+
+  return TRUE;
+}
+
+#endif	/* MACH_XEN */