[kernel] Have process_start syscall take a list of handles

This also prompted a change of the process initialization protocol to
allow handles to get typed, and changing to marking them as just
self/other handls. This also means exposing the object type enum to
userspace.

src/drivers/fb/main.cpp

@@ -41,7 +41,7 @@ main(int argc, const char **argv)
 	j6_init_framebuffer *fb = nullptr;
 	for (unsigned i = 0; i < initc; ++i) {
 		if (initv[i].type == j6_init_desc_framebuffer) {
-			fb = reinterpret_cast<j6_init_framebuffer*>(initv[i].value);
+			fb = reinterpret_cast<j6_init_framebuffer*>(initv[i].data);
 			break;
 		}
 	}

src/drivers/nulldrv/main.cpp

@@ -15,7 +15,6 @@ extern j6_handle_t __handle_sys;
 j6_handle_t endp = j6_handle_invalid;
 
 extern "C" {
-	void _init_libc(j6_process_init *);
 	int main(int, const char **);
 }
 

src/include/j6/init.h

@@ -3,18 +3,25 @@
 /// Types used in process and thread initialization
 
 #include <stdint.h>
+#include "j6/types.h"
 
 enum j6_init_type {					// `value` is a:
-	j6_init_handle_system,			// Handle to the system
-	j6_init_handle_process,			// Handle to this process
-	j6_init_handle_thread,			// Handle to this thread
-	j6_init_handle_space,			// Handle to this process' address space
+	j6_init_handle_self,			// Handle to the system
+	j6_init_handle_other,			// Handle to this process
 	j6_init_desc_framebuffer		// Pointer to a j6_init_framebuffer descriptor
 };
 
+struct j6_typed_handle {
+	enum j6_object_type type;
+	j6_handle_t handle;
+};
+
 struct j6_init_value {
 	enum j6_init_type type;
-	uint64_t value;
+	union {
+		struct j6_typed_handle handle;
+		void *data;
+	};
 };
 
 /// Structure defining a framebuffer.

src/include/j6/object_types.inc

@@ -0,0 +1,12 @@
+OBJECT_TYPE( none,     0x00 )
+
+OBJECT_TYPE( system,   0x01 )
+
+OBJECT_TYPE( event,    0x02 )
+OBJECT_TYPE( channel,  0x03 )
+OBJECT_TYPE( endpoint, 0x04 )
+
+OBJECT_TYPE( vma,      0x05 )
+
+OBJECT_TYPE( process,  0x06 )
+OBJECT_TYPE( thread,   0x07 )

src/include/j6/types.h

@@ -36,15 +36,10 @@ typedef uint64_t j6_handle_t;
 #define j6_handle_id_mask 0xffffffffull
 #define j6_handle_invalid 0xffffffffull
 
-/// A process' initial data structure for communicating with the system
-struct j6_process_init
-{
-	j6_handle_t process;
-	j6_handle_t handles[3];
-};
+enum j6_object_type {
+#define OBJECT_TYPE( name, val ) j6_object_type_ ## name = val,
+#include "j6/object_types.inc"
+#undef OBJECT_TYPE
 
-/// A thread's initial data structure
-struct j6_thread_init
-{
-	j6_handle_t thread;
+	j6_object_type_max
 };

src/include/syscalls.inc

@@ -9,7 +9,7 @@ SYSCALL(0x0a, object_signal,     j6_handle_t, j6_signal_t)
 SYSCALL(0x0b, object_close,      j6_handle_t)
 
 SYSCALL(0x10, process_create,    j6_handle_t *)
-SYSCALL(0x11, process_start,     j6_handle_t *, uintptr_t)
+SYSCALL(0x11, process_start,     j6_handle_t, uintptr_t, j6_handle_t *, size_t)
 SYSCALL(0x11, process_kill,      j6_handle_t)
 SYSCALL(0x17, process_exit,      int32_t)
 

src/kernel/objects/kobject.h

@@ -16,17 +16,9 @@ public:
 	/// Types of kernel objects.
 	enum class type : uint16_t
 	{
-		none,
-		system,
-
-		event,
-		channel,
-		endpoint,
-
-		vma,
-
-		process,
-		thread,
+#define OBJECT_TYPE( name, val ) name = val,
+#include "j6/object_types.inc"
+#undef OBJECT_TYPE
 
 		max
 	};

src/kernel/scheduler.cpp

@@ -119,27 +119,26 @@ load_process_image(const kernel::args::program *program)
 		fb_desc->flags |= 1;
 
 	j6_init_value *initv = push<j6_init_value>(tcb->rsp3);
-	initv->type = j6_init_handle_system;
-	initv->value = static_cast<uint64_t>(proc.add_handle(&system::get()));
+	initv->type = j6_init_handle_other;
+	initv->handle.type = j6_object_type_system;
+	initv->handle.handle = proc.add_handle(&system::get());
 
 	initv = push<j6_init_value>(tcb->rsp3);
-	initv->type = j6_init_handle_process;
-	initv->value = static_cast<uint64_t>(proc.self_handle());
+	initv->type = j6_init_handle_self;
+	initv->handle.type = j6_object_type_process;
+	initv->handle.handle = proc.self_handle();
 
 	initv = push<j6_init_value>(tcb->rsp3);
-	initv->type = j6_init_handle_thread;
-	initv->value = static_cast<uint64_t>(th.self_handle());
-
-	initv = push<j6_init_value>(tcb->rsp3);
-	initv->type = j6_init_handle_space;
-	//initv->value = static_cast<uint64_t>(proc.add_handle(&space));
+	initv->type = j6_init_handle_self;
+	initv->handle.type = j6_object_type_thread;
+	initv->handle.handle = th.self_handle();
 
 	initv = push<j6_init_value>(tcb->rsp3);
 	initv->type = j6_init_desc_framebuffer;
-	initv->value = reinterpret_cast<uint64_t>(fb_desc);
+	initv->data = fb_desc;
 
 	uint64_t *initc = push<uint64_t>(tcb->rsp3);
-	*initc = 5;
+	*initc = 4;
 
 	char **argv0 = push<char*>(tcb->rsp3);
 	*argv0 = message_arg;

src/kernel/syscalls/process.cpp

@@ -16,8 +16,18 @@ process_create(j6_handle_t *handle)
 }
 
 j6_status_t
-process_start(j6_handle_t *handle, uintptr_t entrypoint)
+process_start(j6_handle_t handle, uintptr_t entrypoint, j6_handle_t *handles, size_t handle_count)
 {
+	process &p = process::current();
+	process *c = get_handle<process>(handle);
+	if (handle_count && !handles)
+		return j6_err_invalid_arg;
+
+	for (size_t i = 0; i < handle_count; ++i) {
+		kobject *o = p.lookup_handle(handles[i]);
+		if (o) c->add_handle(o);
+	}
+
 	return j6_err_nyi;
 }
 

src/libraries/libc/arch/x86_64/init_libc.c

@@ -28,8 +28,9 @@ _init_libc(uint64_t *rsp)
 	__initv = (struct j6_init_value *)rsp;
 
 	for (unsigned i = 0; i < __initc; ++i) {
-		if (__initv[i].type == j6_init_handle_system) {
-			__handle_sys = __initv[i].value;
+		if (__initv[i].type == j6_init_handle_other &&
+			__initv[i].handle.type == j6_object_type_system) {
+			__handle_sys = __initv[i].handle.handle;
 			break;
 		}
 	}