weenix

1 files changed, 73 insertions, 2 deletions

diff --git a/kernel/proc/fork.c b/kernel/proc/fork.c
index 28f9f9c..cbf5e30 100644
--- a/kernel/proc/fork.c
+++ b/kernel/proc/fork.c
@@ -57,6 +57,77 @@ static uintptr_t fork_setup_stack(const regs_t *regs, void *kstack)
  */
 long do_fork(struct regs *regs)
 {
-    NOT_YET_IMPLEMENTED("VM: do_fork");
-    return -1;
+    // NOT_YET_IMPLEMENTED("VM: do_fork");
+
+    // Create a new process
+    proc_t *child_proc = proc_create("child from fork");
+    if (child_proc == NULL)
+    {
+        return -ENOMEM;
+    }
+    // Create a new thread
+    kthread_t *child_thread = kthread_clone(curthr);
+    if (child_thread == NULL)
+    {
+        proc_destroy(child_proc);
+        return -ENOMEM;
+    }
+
+    // Set the child process's parent to the current process
+    // child_thread->kt_proc = child_proc;
+    // list_insert_head(&child_proc->p_threads, &child_thread->kt_plink);
+
+    // Get the new vmmap_t for the child process
+    // vmmap_t *child_vmmap = vmmap_clone(curproc->p_vmmap);
+    // if (child_vmmap == NULL)
+    // {
+    //     kthread_destroy(child_thread);
+    //     proc_destroy(child_proc);
+    //     return -ENOMEM;
+    // }
+
+    // Set the new vmmap_t for the child process
+    // child_proc->p_vmmap = child_vmmap;
+    // // Set the vmmap to the child process
+    // child_thread->kt_proc = child_proc;
+
+    // Set the working directory of the child process to the current process
+    // vref(curproc->p_cwd);
+    // child_proc->p_cwd = curproc->p_cwd;
+
+    // Copy over each file descriptor from the parent to the child
+    // for (int i = 0; i < NFILES; i++)
+    // {
+    //     if (curproc->p_files[i] != NULL)
+    //     {
+    //         fref(curproc->p_files[i]);
+    //         child_proc->p_files[i] = curproc->p_files[i];
+    //     }
+    // }
+
+    // Fix the values of the registers and the rest of the kthread's ctx
+    regs->r_rax = 0; // Set the return value to 0 for the child
+    child_thread->kt_ctx.c_rsp = fork_setup_stack(regs, child_thread->kt_kstack); // Set the stack pointer for the child
+    child_thread->kt_ctx.c_rip = (uintptr_t) userland_entry; // Set the instruction pointer to userland_entry
+    // child_thread->kt_ctx.c_rbp = curthr->kt_ctx.c_rbp; // Set the current thread's base pointer to the child's base pointer
+    child_thread->kt_ctx.c_pml4 = curproc->p_pml4; // Set the current thread's page table to the current proc's
+    child_thread->kt_proc = child_proc; // Set the child process to the child thread
+
+    // Update the list
+    list_insert_tail(&child_proc->p_threads, &child_thread->kt_plink);
+
+
+    // Update the brks for the child process
+    // child_proc->p_brk = curproc->p_brk;
+    // child_proc->p_start_brk = curproc->p_start_brk;
+
+    // Unmap the parent's page table and flush the TLB
+    pt_unmap_range(curproc->p_pml4, USER_MEM_LOW, USER_MEM_HIGH);
+    tlb_flush_all();
+
+    // Prepare the child process to be run on the CPU
+    sched_make_runnable(child_thread);
+
+    // Return the child's process id to the parent
+    return child_proc->p_pid;
 }