create impl and CAP_PROC checking

7 files changed, 68 insertions, 15 deletions

diff --git a/arch/riscv64/kernel/cpu.c b/arch/riscv64/kernel/cpu.c
index a730b87..d6d07ec 100644
--- a/arch/riscv64/kernel/cpu.c
+++ b/arch/riscv64/kernel/cpu.c
@@ -11,6 +11,7 @@
 
 #include <arch/cpu.h>
 
+/** Keeps track of initialized cpus. */
 static atomic_long cpus = 0;
 
 void cpu_assign(struct tcb *t)
diff --git a/common/proc.c b/common/proc.c
index 270ec0c..137a2fe 100644
--- a/common/proc.c
+++ b/common/proc.c
@@ -39,6 +39,9 @@ stat_t init_proc(void *fdt)
 	/* set current tcb */
 	use_tcb(t);
 
+	/* init process has all capabilities */
+	set_caps(t->caps, 0, CAP_CAPS | CAP_PROC | CAP_CALL);
+
 	/* allocate stacks after ELF file to make sure nothing of importance
 	 * clashes */
 	return prepare_proc(t, get_init_base(fdt), 0);
diff --git a/common/tcb.c b/common/tcb.c
index 675aa1f..1c1a623 100644
--- a/common/tcb.c
+++ b/common/tcb.c
@@ -300,6 +300,12 @@ __weak struct tcb *cur_tcb()
 struct tcb *cur_proc()
 {
 	struct tcb *t = cur_tcb();
+	return get_tcb(t->pid);
+}
+
+struct tcb *eff_proc()
+{
+	struct tcb *t = cur_tcb();
 	return get_tcb(t->eid);
 }
 
diff --git a/common/uapi/proc.c b/common/uapi/proc.c
index ea42a3a..0039195 100644
--- a/common/uapi/proc.c
+++ b/common/uapi/proc.c
@@ -17,16 +17,25 @@
 /**
  * Create syscall handler.
  *
- * \todo Implement.
- *
  * @param func Function to jump to at thread creation.
- * @param arg Argument to pass to the function.
+ * @param d0 Argument 0.
+ * @param d1 Argument 1.
+ * @param d2 Argument 2.
+ * @param d3 Argument 3.
  *
- * @return \ref OK and 0.
+ * @return ERR_OOMEM if thread creation was unsuccessful, otherwise OK and the
+ * thread id.
  */
 SYSCALL_DEFINE5(create)(sys_arg_t func,
-		sys_arg_t d0, sys_arg_t d1, sys_arg_t d2, sys_arg_t d3){
-	return SYS_RET1(OK);
+                        sys_arg_t d0, sys_arg_t d1, sys_arg_t d2, sys_arg_t d3){
+	struct tcb *t = create_thread(cur_tcb());
+	if (!t)
+		return SYS_RET1(ERR_OOMEM);
+
+	set_args(t, SYS_RET5(t->tid, d0, d1, d2, d3));
+	set_return(t, func);
+
+	return SYS_RET2(OK, t->tid);
 }
 
 /**
@@ -45,7 +54,11 @@ SYSCALL_DEFINE5(create)(sys_arg_t func,
  * @return \ref OK and 0.
  */
 SYSCALL_DEFINE0(fork)(){
-	struct tcb *t = create_proc(cur_proc());
+	struct tcb *c = cur_proc();
+	if (!(get_caps(c->caps, 0) & CAP_PROC))
+		return SYS_RET1(ERR_PERM);
+
+	struct tcb *t = create_proc(eff_proc());
 	if (!t)
 		return SYS_RET1(ERR_OOMEM);
 
@@ -103,6 +116,10 @@ SYSCALL_DEFINE2(exec)(sys_arg_t bin, sys_arg_t interp){
  */
 SYSCALL_DEFINE2(spawn)(sys_arg_t bin, sys_arg_t interp)
 {
+	struct tcb *c = cur_proc();
+	if (!(get_caps(c->caps, 0) & CAP_PROC))
+		return SYS_RET1(ERR_PERM);
+
 	struct tcb *t = create_proc(NULL);
 	if (!t)
 		return SYS_RET1(ERR_OOMEM);
@@ -120,6 +137,10 @@ SYSCALL_DEFINE2(spawn)(sys_arg_t bin, sys_arg_t interp)
  */
 SYSCALL_DEFINE1(kill)(sys_arg_t tid)
 {
+	struct tcb *c = cur_proc();
+	if (!(get_caps(c->caps, 0) & CAP_PROC))
+		return SYS_RET1(ERR_PERM);
+
 	return SYS_RET1(OK);
 }
 
@@ -134,6 +155,10 @@ SYSCALL_DEFINE1(kill)(sys_arg_t tid)
  * @return \ref OK.
  */
 SYSCALL_DEFINE1(swap)(sys_arg_t tid){
+	struct tcb *c = cur_proc();
+	if (!(get_caps(c->caps, 0) & CAP_PROC))
+		return SYS_RET1(ERR_PERM);
+
 	struct tcb *t = get_tcb(tid);
 	if (!t)
 		return SYS_RET1(ERR_INVAL);
diff --git a/include/apos/caps.h b/include/apos/caps.h
index b64b05a..e8ef76b 100644
--- a/include/apos/caps.h
+++ b/include/apos/caps.h
@@ -22,9 +22,6 @@ enum {
 
 	/** Thread is allowed to force interrupt to callback in other thread. */
 	CAP_CALL = (1 << 2),
-
-	/** Thread is allowed to assign threads to processors. */
-	CAP_ASSIGN = (1 << 3),
 };
 
 /**
diff --git a/include/apos/tcb.h b/include/apos/tcb.h
index a31e308..b92cd10 100644
--- a/include/apos/tcb.h
+++ b/include/apos/tcb.h
@@ -268,11 +268,18 @@ struct tcb *cur_tcb();
 /**
  * Get currently executing process.
  *
- * @return Current process \ref tcb.
+ * @return Effective process \ref tcb.
  */
 struct tcb *cur_proc();
 
 /**
+ * Get currently executing process.
+ *
+ * @return Effective process \ref tcb.
+ */
+struct tcb *eff_proc();
+
+/**
  * Set \c t as current \ref tcb.
  *
  * Also updates the current cpu id of the tcb.
diff --git a/include/apos/uapi.h b/include/apos/uapi.h
index 7d612b6..084c1fa 100644
--- a/include/apos/uapi.h
+++ b/include/apos/uapi.h
@@ -51,12 +51,25 @@ struct sys_ret {
 	sys_arg_t ar4;
 };
 
+/** Helper for returning sys_ret with 0 arguments. */
 #define SYS_RET0() (struct sys_ret){0, 0, 0, 0, 0, 0}
+
+/** Helper for returning sys_ret with 1 arguments. */
 #define SYS_RET1(a) (struct sys_ret){a, 0, 0, 0, 0, 0}
+
+/** Helper for returning sys_ret with 2 arguments. */
 #define SYS_RET2(a, b) (struct sys_ret){a, b, 0, 0, 0, 0}
+
+/** Helper for returning sys_ret with 3 arguments. */
 #define SYS_RET3(a, b, c) (struct sys_ret){a, b, c, 0, 0, 0}
+
+/** Helper for returning sys_ret with 4 arguments. */
 #define SYS_RET4(a, b, c, d) (struct sys_ret){a, b, c, d, 0, 0}
+
+/** Helper for returning sys_ret with 5 arguments. */
 #define SYS_RET5(a, b, c, d, e) (struct sys_ret){a, b, c, d, e, 0}
+
+/** Helper for returning sys_ret with 6 arguments. */
 #define SYS_RET6(a, b, c, d, e, f) (struct sys_ret){a, b, c, d, e, f}
 
 /**
@@ -504,10 +517,11 @@ SYSCALL_DECLARE2(ipc_notify, tid, swap);
  * Creates thread in current effective process context.
  *
  * @param func Function to call on startup.
- * @param arg Argument to pass to function.
- * @param c Unused.
- * @param d Unused.
- * @param e Unused.
+ * @param d0 Argument 0.
+ * @param d1 Argument 1.
+ * @param d2 Argument 2.
+ * @param d3 Argument 3.
+ *
  * @return \ref OK and 0.
  * \todo Should this take stack size etc?
  */