WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/mm/as.c

 #include <arch/mm/asid.h>
 #include <synch/spinlock.h>
 #include <adt/list.h>
 #include <adt/btree.h>
 #include <proc/task.h>
+#include <proc/thread.h>
 #include <arch/asm.h>
 #include <panic.h>
 #include <debug.h>
 #include <print.h>
 #include <memstr.h>
 #include <arch.h>
 #include <errno.h>
 #include <config.h>
 #include <arch/types.h>
 #include <typedefs.h>
+#include <syscall/copy.h>
+#include <arch/interrupt.h>
 as_operations_t *as_operations = NULL;
 /** Address space lock. It protects inactive_as_with_asid_head. */
 SPINLOCK_INITIALIZE(as_lock);
+ *
  * This is the high-level page fault handler.
  * Interrupts are assumed disabled.
+ *
  * @param page Faulting page.
+ * @param istate Pointer to interrupted state.
+ *
- * @return 0 on page fault, 1 on success.
+ * @return 0 on page fault, 1 on success or 2 if the fault was caused by copy_to_uspace() or copy_from_uspace().
  */
-int as_page_fault(__address page)
+int as_page_fault(__address page, istate_t *istate)
+{
     pte_t *pte;
     as_area_t *area;
     __address frame;
         /*
          * No area contained mapping for 'page'.
          * Signal page fault to low-level handler.
          */
         spinlock_unlock(&AS->lock);
-        return 0;
+        goto page_fault;
+    }
     if (area->attributes & AS_AREA_ATTR_PARTIAL) {
         /*
          * The address space area is not fully initialized.
          * Avoid possible race by returning error.
          */
         spinlock_unlock(&area->lock);
         spinlock_unlock(&AS->lock);
-        return 0;
+        goto page_fault;
+    }
     ASSERT(!(area->flags & AS_AREA_DEVICE));
     page_table_lock(AS, false);
     page_mapping_insert(AS, page, frame, get_area_flags(area));
     page_table_unlock(AS, false);
     spinlock_unlock(&area->lock);
     spinlock_unlock(&AS->lock);
-    return 1;
+    return AS_PF_OK;
+page_fault:
+    if (!THREAD)
+        return AS_PF_FAULT;
+    if (THREAD->in_copy_from_uspace) {
+        THREAD->in_copy_from_uspace = false;
+        istate_set_retaddr(istate, (__address) &memcpy_from_uspace_failover_address);
+    } else if (THREAD->in_copy_to_uspace) {
+        THREAD->in_copy_to_uspace = false;
+        istate_set_retaddr(istate, (__address) &memcpy_to_uspace_failover_address);
+    } else {
+        return AS_PF_FAULT;
+    }
+    return AS_PF_DEFER;
+}
 /** Switch address spaces.
+ *
  * @param old Old address space or NULL.
  *     TASK. Otherwise zero is returned.
  */
 __native sys_as_area_accept(as_area_acptsnd_arg_t *uspace_accept_arg)
+{
     as_area_acptsnd_arg_t arg;
+    int rc;
-    copy_from_uspace(&arg, uspace_accept_arg, sizeof(as_area_acptsnd_arg_t));
+    rc = copy_from_uspace(&arg, uspace_accept_arg, sizeof(as_area_acptsnd_arg_t));
+    if (rc != 0)
+        return rc;
     if (!arg.size)
         return (__native) EPERM;
     if (arg.task_id == TASK->taskid) {
 /** Wrapper for as_area_send. */
 __native sys_as_area_send(as_area_acptsnd_arg_t *uspace_send_arg)
+{
     as_area_acptsnd_arg_t arg;
+    int rc;
-    copy_from_uspace(&arg, uspace_send_arg, sizeof(as_area_acptsnd_arg_t));
+    rc = copy_from_uspace(&arg, uspace_send_arg, sizeof(as_area_acptsnd_arg_t));
+    if (rc != 0)
+        return rc;
     if (!arg.size)
         return (__native) EPERM;
     if (arg.task_id == TASK->taskid) {

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/mm/as.c – Rev 1248 → 1288