Xenbus implementation ported from Linux to Mini-os, simple thread support introduced

to simplify the porting. 64 bit version of Mini-os now compiles, but does not work
because of the pagetables and some bits of scheduler not being written.

Signed-off-by: Grzegorz Milos <gm281@cam.ac.uk>

1 files changed, 91 insertions, 0 deletions

diff --git a/extras/mini-os/include/wait.h b/extras/mini-os/include/wait.h
new file mode 100644
index 0000000000..4c23855620
--- /dev/null
+++ b/extras/mini-os/include/wait.h
@@ -0,0 +1,91 @@
+#ifndef __WAIT_H__
+#define __WAIT_H__
+
+#include <sched.h>
+#include <list.h>
+#include <lib.h>
+#include <os.h>
+
+struct wait_queue
+{
+    struct thread *thread;
+    struct list_head thread_list;
+};
+
+struct wait_queue_head
+{
+    /* TODO - lock required? */
+    struct list_head thread_list;
+};
+
+#define DECLARE_WAIT_QUEUE_HEAD(name) \
+   struct wait_queue_head name =     \
+        { .thread_list = { &(name).thread_list, &(name).thread_list} }
+
+#define __WAIT_QUEUE_HEAD_INITIALIZER(name) {                           \
+    .thread_list      = { &(name).thread_list, &(name).thread_list } }
+
+
+#define DEFINE_WAIT(name)                               \
+struct wait_queue name = {                              \
+    .thread       = current,                            \
+    .thread_list  = LIST_HEAD_INIT((name).thread_list), \
+}
+
+
+
+static inline void init_waitqueue_entry(struct wait_queue *q, struct thread *thread)
+{
+    q->thread = thread;
+}
+
+
+static inline void add_wait_queue(struct wait_queue_head *h, struct wait_queue *q)
+{
+    if (list_empty(&q->thread_list))
+        list_add(&q->thread_list, &h->thread_list);   
+}
+
+static inline void remove_wait_queue(struct wait_queue *q)
+{
+    list_del(&q->thread_list);
+}
+
+static inline void wake_up(struct wait_queue_head *head)
+{
+    struct list_head *tmp, *next;
+    list_for_each_safe(tmp, next, &head->thread_list)
+    {
+         struct wait_queue *curr;
+         curr = list_entry(tmp, struct wait_queue, thread_list);
+         wake(curr->thread);
+    }
+}
+
+#define wait_event(wq, condition) do{             \
+    unsigned long flags;                          \
+    if(condition)                                 \
+        break;                                    \
+    DEFINE_WAIT(__wait);                          \
+    for(;;)                                       \
+    {                                             \
+        /* protect the list */                    \
+        local_irq_save(flags);                    \
+        add_wait_queue(&wq, &__wait);             \
+        block(current);                           \
+        local_irq_restore(flags);                 \
+        if(condition)                             \
+            break;                                \
+        schedule();                               \
+    }                                             \
+    local_irq_save(flags);                        \
+    /* need to wake up */                         \
+    wake(current);                                \
+    remove_wait_queue(&__wait);                   \
+    local_irq_restore(flags);                     \
+} while(0) 
+
+
+
+
+#endif /* __WAIT_H__ */