per-process virtual memory

VGA is only mapped into the virtual memory because there are no other
ways of interacting with the OS.

1 files changed, 16 insertions, 5 deletions

diff --git a/src/kernel/proc.c b/src/kernel/proc.c
index 4a931a5..6b80254 100644
--- a/src/kernel/proc.c
+++ b/src/kernel/proc.c
@@ -1,19 +1,30 @@
 #include <kernel/arch/generic.h>
 #include <kernel/mem.h>
 #include <kernel/proc.h>
+#include <stdint.h>
 
 struct process *process_current;
 
-struct process *process_new(void *eip) {
-	struct process *proc;
-	proc = page_alloc(1); // TODO kmalloc
-	proc->stack_top = proc->esp = page_alloc(1) + 1 * PAGE_SIZE;
-	proc->eip = eip;
+struct process *process_new() {
+	struct process *proc = page_alloc(1); // TODO kmalloc
+	proc->pages = pagedir_new();
 
+	// map the stack to the last page in memory
+	pagedir_map(proc->pages, (void*)~PAGE_MASK, page_alloc(1), true, true);
+	proc->stack_top = proc->esp = (void*) ~0;
+
+	// map the kernel
+	//   yup, .text is writeable too. the plan is to not map the kernel
+	//   into user memory at all, but i'll implement that later. TODO
+	for (size_t p = 0x100000; p < &_bss_end; p += PAGE_SIZE)
+		pagedir_map(proc->pages, (void*)p, (void*)p, false, true);
+
+	// the kernel still has to load the executable code and set EIP
 	return proc;
 }
 
 void process_switch(struct process *proc) {
 	process_current = proc;
+	pagedir_switch(proc->pages);
 	sysexit(proc->eip, proc->esp);
 }