kernel: sched: Expose sched_init_stack()

Signed-off-by: Ian Moffett <ian@osmora.org>

2 files changed, 58 insertions, 57 deletions

diff --git a/sys/include/sys/sched.h b/sys/include/sys/sched.h
index 8245120..01a58fe 100644
--- a/sys/include/sys/sched.h
+++ b/sys/include/sys/sched.h
@@ -43,6 +43,7 @@ void sched_init(void);
 void sched_exit(void);
 void sched_context_switch(struct trapframe *tf);
 void sched_rest(void);
+uintptr_t sched_init_stack(void *stack_top, struct exec_args args);
 
 __noreturn
 uint64_t sys_exit(struct syscall_args *args);
diff --git a/sys/kern/kern_sched.c b/sys/kern/kern_sched.c
index c362b98..669d255 100644
--- a/sys/kern/kern_sched.c
+++ b/sys/kern/kern_sched.c
@@ -139,63 +139,6 @@ sched_enter(void)
 }
 
 static uintptr_t
-sched_init_stack(void *stack_top, struct exec_args args)
-{
-    uintptr_t *sp = stack_top;
-    uintptr_t old_sp = 0;
-    size_t argc, envc, len;
-    char **argvp = args.argp;
-    char **envp = args.envp;
-    struct auxval auxv = args.auxv;
-
-    /* Copy strings */
-    old_sp = (uintptr_t)sp;
-    for (argc = 0; argvp[argc] != NULL; ++argc) {
-        len = strlen(argvp[argc]) + 1;
-        sp = (void *)((char *)sp - len);
-        memcpy((char *)sp, argvp[argc], len);
-    }
-    for (envc = 0; envp[envc] != NULL; ++envc) {
-        len = strlen(envp[envc]) + 1;
-        sp = (void *)((char *)sp - len);
-        memcpy((char *)sp, envp[envc], len);
-    }
-
-    /* Ensure the stack is aligned */
-    sp = (void *)__ALIGN_DOWN((uintptr_t)sp, 16);
-    if (((argc + envc + 1) & 1) != 0)
-        --sp;
-
-    AUXVAL(sp, AT_NULL, 0x0);
-    AUXVAL(sp, AT_SECURE, 0x0);
-    AUXVAL(sp, AT_ENTRY, auxv.at_entry);
-    AUXVAL(sp, AT_PHDR, auxv.at_phdr);
-    AUXVAL(sp, AT_PHNUM, auxv.at_phnum);
-    AUXVAL(sp, AT_PAGESIZE, vm_get_page_size());
-    STACK_PUSH(sp, 0);
-
-    /* Copy envp pointers */
-    sp -= envc;
-    for (int i = 0; i < envc; ++i) {
-        len = strlen(envp[i]) + 1;
-        old_sp -= len;
-        sp[i] = KERN_TO_USER(old_sp);
-    }
-
-    /* Copy argvp pointers */
-    STACK_PUSH(sp, 0);
-    sp -= argc;
-    for (int i = 0; i < argc; ++i) {
-        len = strlen(argvp[i]) + 1;
-        old_sp -= len;
-        sp[i] = KERN_TO_USER(old_sp);
-    }
-
-    STACK_PUSH(sp, argc);
-    return (uintptr_t)sp;
-}
-
-static uintptr_t
 sched_create_stack(struct vas vas, bool user, struct exec_args args,
                    struct proc *td)
 {
@@ -345,6 +288,63 @@ sched_make_idletd(void)
     sched_enqueue_td(td);
 }
 
+uintptr_t
+sched_init_stack(void *stack_top, struct exec_args args)
+{
+    uintptr_t *sp = stack_top;
+    uintptr_t old_sp = 0;
+    size_t argc, envc, len;
+    char **argvp = args.argp;
+    char **envp = args.envp;
+    struct auxval auxv = args.auxv;
+
+    /* Copy strings */
+    old_sp = (uintptr_t)sp;
+    for (argc = 0; argvp[argc] != NULL; ++argc) {
+        len = strlen(argvp[argc]) + 1;
+        sp = (void *)((char *)sp - len);
+        memcpy((char *)sp, argvp[argc], len);
+    }
+    for (envc = 0; envp[envc] != NULL; ++envc) {
+        len = strlen(envp[envc]) + 1;
+        sp = (void *)((char *)sp - len);
+        memcpy((char *)sp, envp[envc], len);
+    }
+
+    /* Ensure the stack is aligned */
+    sp = (void *)__ALIGN_DOWN((uintptr_t)sp, 16);
+    if (((argc + envc + 1) & 1) != 0)
+        --sp;
+
+    AUXVAL(sp, AT_NULL, 0x0);
+    AUXVAL(sp, AT_SECURE, 0x0);
+    AUXVAL(sp, AT_ENTRY, auxv.at_entry);
+    AUXVAL(sp, AT_PHDR, auxv.at_phdr);
+    AUXVAL(sp, AT_PHNUM, auxv.at_phnum);
+    AUXVAL(sp, AT_PAGESIZE, vm_get_page_size());
+    STACK_PUSH(sp, 0);
+
+    /* Copy envp pointers */
+    sp -= envc;
+    for (int i = 0; i < envc; ++i) {
+        len = strlen(envp[i]) + 1;
+        old_sp -= len;
+        sp[i] = KERN_TO_USER(old_sp);
+    }
+
+    /* Copy argvp pointers */
+    STACK_PUSH(sp, 0);
+    sp -= argc;
+    for (int i = 0; i < argc; ++i) {
+        len = strlen(argvp[i]) + 1;
+        old_sp -= len;
+        sp[i] = KERN_TO_USER(old_sp);
+    }
+
+    STACK_PUSH(sp, argc);
+    return (uintptr_t)sp;
+}
+
 /*
  * Cause an early preemption and lets
  * the next thread run.