[kernel] Consolodate koid and close syscalls

A number of object types had _close or _koid syscalls. Moved those to be
generic for kobject.

src/kernel/syscalls/channel.cpp

@@ -13,15 +13,6 @@ channel_create(j6_handle_t *handle)
 	return j6_status_ok;
 }
 
-j6_status_t
-channel_close(j6_handle_t handle)
-{
-	channel *c = remove_handle<channel>(handle);
-	if (!c) return j6_err_invalid_arg;
-	c->close();
-	return j6_status_ok;
-}
-
 j6_status_t
 channel_send(j6_handle_t handle, size_t *len, void *data)
 {

src/kernel/syscalls/endpoint.cpp

@@ -15,15 +15,6 @@ endpoint_create(j6_handle_t *handle)
 	return j6_status_ok;
 }
 
-j6_status_t
-endpoint_close(j6_handle_t handle)
-{
-	endpoint *e = remove_handle<endpoint>(handle);
-	if (!e) return j6_err_invalid_arg;
-	e->close();
-	return j6_status_ok;
-}
-
 j6_status_t
 endpoint_send(j6_handle_t handle, j6_tag_t tag, size_t len, void *data)
 {

src/kernel/syscalls/helpers.h

@@ -3,6 +3,7 @@
 /// Utility functions for use in syscall handler implementations
 
 #include "j6/types.h"
+#include "objects/kobject.h"
 #include "objects/process.h"
 
 namespace syscalls {
@@ -26,6 +27,13 @@ T * get_handle(j6_handle_t handle)
 	return static_cast<T*>(o);
 }
 
+template <>
+inline kobject * get_handle<kobject>(j6_handle_t handle)
+{
+	process &p = process::current();
+	return p.lookup_handle(handle);
+}
+
 template <typename T>
 T * remove_handle(j6_handle_t handle)
 {

src/kernel/syscalls/object.cpp

@@ -3,18 +3,29 @@
 #include "j6/types.h"
 
 #include "log.h"
-#include "objects/process.h"
 #include "objects/thread.h"
+#include "syscalls/helpers.h"
 
 namespace syscalls {
 
+j6_status_t
+object_koid(j6_handle_t handle, j6_koid_t *koid)
+{
+	if (koid == nullptr)
+		return j6_err_invalid_arg;
+
+	kobject *obj = get_handle<kobject>(handle);
+	if (!obj)
+		return j6_err_invalid_arg;
+
+	*koid = obj->koid();
+	return j6_status_ok;
+}
+
 j6_status_t
 object_wait(j6_handle_t handle, j6_signal_t mask, j6_signal_t *sigs)
 {
-	thread &th = thread::current();
-	process &p = process::current();
-
-	kobject *obj = p.lookup_handle(handle);
+	kobject *obj = get_handle<kobject>(handle);
 	if (!obj)
 		return j6_err_invalid_arg;
 
@@ -24,6 +35,7 @@ object_wait(j6_handle_t handle, j6_signal_t mask, j6_signal_t *sigs)
 		return j6_status_ok;
 	}
 
+	thread &th = thread::current();
 	obj->add_blocked_thread(&th);
 	th.wait_on_signals(obj, mask);
 
@@ -40,8 +52,7 @@ object_signal(j6_handle_t handle, j6_signal_t signals)
 	if ((signals & j6_signal_user_mask) != signals)
 		return j6_err_invalid_arg;
 
-	process &p = process::current();
-	kobject *obj = p.lookup_handle(handle);
+	kobject *obj = get_handle<kobject>(handle);
 	if (!obj)
 		return j6_err_invalid_arg;
 
@@ -49,4 +60,15 @@ object_signal(j6_handle_t handle, j6_signal_t signals)
 	return j6_status_ok;
 }
 
+j6_status_t
+object_close(j6_handle_t handle)
+{
+	kobject *obj = get_handle<kobject>(handle);
+	if (!obj)
+		return j6_err_invalid_arg;
+
+	obj->close();
+	return j6_status_ok;
+}
+
 } // namespace syscalls

src/kernel/syscalls/process.cpp

@@ -6,16 +6,6 @@
 
 namespace syscalls {
 
-j6_status_t
-process_koid(j6_koid_t *koid)
-{
-	if (koid == nullptr)
-		return j6_err_invalid_arg;
-
-	*koid = process::current().koid();
-	return j6_status_ok;
-}
-
 j6_status_t
 process_exit(int64_t status)
 {

src/kernel/syscalls/thread.cpp

@@ -7,16 +7,6 @@
 
 namespace syscalls {
 
-j6_status_t
-thread_koid(j6_koid_t *koid)
-{
-	if (koid == nullptr)
-		return j6_err_invalid_arg;
-
-	*koid =  thread::current().koid();
-	return j6_status_ok;
-}
-
 j6_status_t
 thread_create(void *rip, j6_handle_t *handle)
 {

src/kernel/syscalls/vm_area.cpp

@@ -47,17 +47,6 @@ vma_unmap(j6_handle_t handle)
 	return j6_status_ok;
 }
 
-j6_status_t
-vma_close(j6_handle_t handle)
-{
-	j6_status_t status = vma_unmap(handle);
-	if (status != j6_status_ok)
-		return status;
-
-	remove_handle<vm_area>(handle);
-	return j6_status_ok;
-}
-
 j6_status_t
 vma_resize(j6_handle_t handle, size_t *size)
 {