Have #ip's protocol ctl()s throw errors
[akaros.git] / kern / include / kthread.h
index e3bd513..0b9f4bf 100644 (file)
@@ -6,13 +6,17 @@
  * reason, usually during blocking IO operations.  Check out
  * Documentation/kthreads.txt for more info than you care about. */
 
-#ifndef ROS_KERN_KTHREAD_H
-#define ROS_KERN_KTHREAD_H
+#pragma once
 
 #include <ros/common.h>
 #include <trap.h>
 #include <sys/queue.h>
 #include <atomic.h>
+#include <setjmp.h>
+
+struct errbuf {
+       struct jmpbuf jmpbuf;
+};
 
 struct proc;
 struct kthread;
@@ -22,21 +26,27 @@ TAILQ_HEAD(semaphore_tailq, semaphore);
 
 #define GENBUF_SZ 128  /* plan9 uses this as a scratch space, per syscall */
 
+#define KTH_IS_KTASK                   (1 << 0)
+#define KTH_SAVE_ADDR_SPACE            (1 << 1)
+#define KTH_KTASK_FLAGS                        (KTH_IS_KTASK)
+#define KTH_DEFAULT_FLAGS              (KTH_SAVE_ADDR_SPACE)
+
 /* This captures the essence of a kernel context that we want to suspend.  When
  * a kthread is running, we make sure its stacktop is the default kernel stack,
  * meaning it will receive the interrupts from userspace. */
 struct kthread {
-       struct kernel_ctx                       context;
+       struct jmpbuf                           context;
        uintptr_t                                       stacktop;
        struct proc                                     *proc;
        struct syscall                          *sysc;
-       void                                            *errbuf;        /* TODO: avoiding include loops */
+       struct errbuf                           *errbuf;
        TAILQ_ENTRY(kthread)            link;
        /* ID, other shit, etc */
-       bool                                            is_ktask;       /* default is FALSE */
+       int                                                     flags;
        char                                            *name;
        char                                            generic_buf[GENBUF_SZ];
        struct systrace_record          *trace;
+       struct systrace_record          *strace;
 };
 
 /* Semaphore for kthreads to sleep on.  0 or less means you need to sleep */
@@ -54,6 +64,23 @@ struct semaphore {
 #endif
 };
 
+/* omitted elements (the sem debug stuff) are initialized to 0 */
+#define SEMAPHORE_INITIALIZER(name, n)                                         \
+{                                                                              \
+    .waiters    = TAILQ_HEAD_INITIALIZER((name).waiters),                      \
+       .nr_signals = (n),                                                         \
+    .lock       = SPINLOCK_INITIALIZER,                                        \
+    .irq_okay   = FALSE,                                                       \
+}
+
+#define SEMAPHORE_INITIALIZER_IRQSAVE(name, n)                                 \
+{                                                                              \
+    .waiters    = TAILQ_HEAD_INITIALIZER((name).waiters),                      \
+       .nr_signals = (n),                                                         \
+    .lock       = SPINLOCK_INITIALIZER_IRQSAVE,                                \
+    .irq_okay   = TRUE,                                                        \
+}
+
 struct cond_var {
        struct semaphore                        sem;
        spinlock_t                                      *lock;          /* usually points to internal_ */
@@ -81,7 +108,14 @@ struct kthread *__kthread_zalloc(void);
 void restart_kthread(struct kthread *kthread);
 void kthread_runnable(struct kthread *kthread);
 void kthread_yield(void);
+void kthread_usleep(uint64_t usec);
 void ktask(char *name, void (*fn)(void*), void *arg);
+
+static inline bool is_ktask(struct kthread *kthread)
+{
+       return kthread->flags & KTH_IS_KTASK;
+}
+
 /* Debugging */
 void check_poison(char *msg);
 
@@ -120,11 +154,14 @@ void __reg_abortable_cv(struct cv_lookup_elm *cle, struct cond_var *cv);
 void dereg_abortable_cv(struct cv_lookup_elm *cle);
 bool should_abort(struct cv_lookup_elm *cle);
 
-/* qlocks are plan9's binary sempahore, which are wrappers around our sems */
+uintptr_t switch_to_ktask(void);
+void switch_back_from_ktask(uintptr_t old_ret);
+
+/* qlocks are plan9's binary sempahore, which are wrappers around our sems.
+ * Not sure if they'll need irqsave or normal sems. */
 typedef struct semaphore qlock_t;
 #define qlock_init(x) sem_init((x), 1)
 #define qlock(x) sem_down(x)
 #define qunlock(x) sem_up(x)
 #define canqlock(x) sem_trydown(x)
-
-#endif /* ROS_KERN_KTHREAD_H */
+#define QLOCK_INITIALIZER(name) SEMAPHORE_INITIALIZER(name, 1)