make process loading more generic

3 files changed, 31 insertions, 17 deletions

diff --git a/arch/riscv64/include/proc.h b/arch/riscv64/include/proc.h
new file mode 100644
index 0000000..c0bf3af
--- /dev/null
+++ b/arch/riscv64/include/proc.h
@@ -0,0 +1,9 @@
+#ifndef APOS_RISCV_PROC_H
+#define APOS_RISCV_PROC_H
+
+/**
+ * @file proc.h
+ * riscv64-specific process-related stuff. Currently empty.
+ */
+
+#endif /* APOS_RISCV_PROC_H */
diff --git a/arch/riscv64/kernel/proc.c b/arch/riscv64/kernel/proc.c
index bbe9782..c95021d 100644
--- a/arch/riscv64/kernel/proc.c
+++ b/arch/riscv64/kernel/proc.c
@@ -8,33 +8,32 @@
 #include "regs.h"
 #include "csr.h"
 
-stat_t jump_to_userspace(struct tcb *t, int argc, char **argv)
+/* TODO: actually map fdt into the target address space */
+stat_t run_init(struct tcb *t, void *fdt)
 {
-	csr_write(CSR_SEPC, t->entry);
 	csr_write(CSR_SSCRATCH, t);
-	__asm__ volatile ("mv sp, %0\n" : : "r" (t->proc_stack_top) : "memory");
+	__asm__ volatile ("mv sp, %0\n" : : "r" (t->thread_stack_top) : "memory");
+	__asm__ volatile ("mv a0, %0\n" : : "r" (fdt) : );
 	__asm__ volatile ("sret\n" ::: "memory");
 	/* we should never reach this */
 	return ERR_ADDR;
 }
 
-stat_t return_to_userspace(struct tcb *t)
+stat_t set_return(vm_t v)
 {
-	/* lol */
-	return ERR_ADDR;
+	csr_write(CSR_SEPC, v);
+	return OK;
 }
 
 stat_t prepare_thread(struct tcb *t)
 {
 	/* get location of registers in memory */
 	/* TODO: check alignment, should be fine but just to be sure */
-	struct riscv_regs *r = (struct riscv_regs *)t;
-	r--;
+	struct riscv_regs *r = (struct riscv_regs *)(--t);
 
-	r->sp = (long)t->proc_stack_top;
+	/* insert important values into register slots */
+	r->sp = (long)t->thread_stack_top;
 	r->tp = (long)t;
 
-	/* set entry point */
-	csr_write(CSR_SEPC, t->entry);
 	return OK;
 }
diff --git a/arch/riscv64/kernel/vmem.c b/arch/riscv64/kernel/vmem.c
index cd5e4c4..73db4dc 100644
--- a/arch/riscv64/kernel/vmem.c
+++ b/arch/riscv64/kernel/vmem.c
@@ -96,12 +96,12 @@ static void __destroy_branch(struct vmem *b)
 	if (!b)
 		return;
 
-	for (size_t i = 0; i < BASE_PAGE_SIZE / sizeof(pm_t); ++i) {
+	for (size_t i = 0; i < RISCV_NUM_LEAVES; ++i) {
 		if (is_branch(b->leaf[i]))
 			__destroy_branch((struct vmem *)pte_addr(b->leaf[i]));
-
-		free_page(MM_KPAGE, (pm_t)pte_addr(b->leaf[i]));
 	}
+
+	free_page(MM_KPAGE, (pm_t)__pa(b));
 }
 
 stat_t map_vpage(struct vmem *branch, pm_t paddr, vm_t vaddr, vmflags_t flags,
@@ -150,7 +150,7 @@ void flush_tlb_all()
 	__asm__ volatile ("sfence.vma\n" ::: "memory");
 }
 
-static void __start_vmem(struct vmem *branch, enum mm_mode m)
+static void __use_vmem(struct vmem *branch, enum mm_mode m)
 {
 	branch = (struct vmem *)__pa(branch);
 
@@ -173,7 +173,7 @@ struct vmem *init_vmem(void *fdt)
 	UNUSED(fdt);
 	struct vmem *b = create_vmem();
 	/* update which memory branch to use */
-	__start_vmem(b, Sv39);
+	use_vmem(b);
 	return b;
 }
 
@@ -186,9 +186,15 @@ struct vmem *create_vmem()
 	return b;
 }
 
+stat_t use_vmem(struct vmem *b)
+{
+	__use_vmem(b, Sv39);
+	return OK;
+}
+
 stat_t destroy_vmem(struct vmem *b)
 {
-	free_page(MM_KPAGE, (pm_t)b);
+	__destroy_branch(b);
 	return OK;
 }