From 50b601614491460dcc76857695b24a5ca13b0737 Mon Sep 17 00:00:00 2001
From: Garen Tyler <garentyler@garen.dev>
Date: Sun, 12 Nov 2023 13:47:22 -0700
Subject: [PATCH] either_copyin and either_copyout

---
 kernel/proc.c                                 | 31 -------------
 kernel/rustkernel/src/arch/mod.rs             |  5 ++-
 .../src/arch/riscv/virtual_memory.rs          | 44 ++++++++++++++++++-
 kernel/rustkernel/src/console/mod.rs          |  8 +---
 4 files changed, 47 insertions(+), 41 deletions(-)

diff --git a/kernel/proc.c b/kernel/proc.c
index b4085d3..b9196c9 100644
--- a/kernel/proc.c
+++ b/kernel/proc.c
@@ -8,7 +8,6 @@
 
 struct proc proc[NPROC];
 struct proc *initproc;
-extern void forkret(void);
 
 // helps ensure that wakeups of wait()ing
 // parents are not lost. helps obey the
@@ -76,33 +75,3 @@ forkret(void)
 
   usertrapret();
 }
-
-// Copy to either a user address, or kernel address,
-// depending on usr_dst.
-// Returns 0 on success, -1 on error.
-int
-either_copyout(int user_dst, uint64 dst, void *src, uint64 len)
-{
-  struct proc *p = myproc();
-  if(user_dst){
-    return copyout(p->pagetable, dst, src, len);
-  } else {
-    memmove((char *)dst, src, len);
-    return 0;
-  }
-}
-
-// Copy from either a user address, or kernel address,
-// depending on usr_src.
-// Returns 0 on success, -1 on error.
-int
-either_copyin(void *dst, int user_src, uint64 src, uint64 len)
-{
-  struct proc *p = myproc();
-  if(user_src){
-    return copyin(p->pagetable, dst, src, len);
-  } else {
-    memmove(dst, (char*)src, len);
-    return 0;
-  }
-}
diff --git a/kernel/rustkernel/src/arch/mod.rs b/kernel/rustkernel/src/arch/mod.rs
index 005693d..51b242c 100644
--- a/kernel/rustkernel/src/arch/mod.rs
+++ b/kernel/rustkernel/src/arch/mod.rs
@@ -46,8 +46,9 @@ pub mod mem {
 pub mod virtual_memory {
     #[cfg(target_arch = "riscv64")]
     pub use super::riscv::virtual_memory::{
-        copyin, copyinstr, copyout, kvminit as init, kvminithart as inithart, mappages, uvmalloc,
-        uvmcopy, uvmcreate, uvmdealloc, uvmfree, uvmunmap,
+        copyin, copyinstr, copyout, either_copyin, either_copyout, kvminit as init,
+        kvminithart as inithart, mappages, uvmalloc, uvmcopy, uvmcreate, uvmdealloc, uvmfree,
+        uvmunmap,
     };
 }
 
diff --git a/kernel/rustkernel/src/arch/riscv/virtual_memory.rs b/kernel/rustkernel/src/arch/riscv/virtual_memory.rs
index 080f850..0297cc3 100644
--- a/kernel/rustkernel/src/arch/riscv/virtual_memory.rs
+++ b/kernel/rustkernel/src/arch/riscv/virtual_memory.rs
@@ -1,6 +1,6 @@
 use super::{
     asm,
-    mem::{make_satp, pte2pa, kstack},
+    mem::{kstack, make_satp, pte2pa},
     plic::PLIC,
     power::QEMU_POWER,
 };
@@ -17,6 +17,7 @@ use crate::{
         kalloc::{kalloc, kfree},
         memmove, memset,
     },
+    proc::process::Process,
 };
 use core::ptr::{addr_of, addr_of_mut, null_mut};
 
@@ -25,6 +26,9 @@ extern "C" {
     pub static etext: [u8; 0];
     /// trampoline.S
     pub static trampoline: [u8; 0];
+
+    // pub fn either_copyin(dst: *mut u8, user_src: i32, src: u64, len: u64) -> i32;
+    // pub fn either_copyout(user_dst: i32, dst: u64, src: *mut u8, len: u64) -> i32;
 }
 
 /// The kernel's pagetable.
@@ -113,7 +117,13 @@ pub unsafe fn kvmmake() -> Pagetable {
             panic!("kalloc");
         }
         let virtual_addr = kstack(i) as u64;
-        kvmmap(pagetable, virtual_addr, page as u64, PAGE_SIZE as u64, PTE_R | PTE_W);
+        kvmmap(
+            pagetable,
+            virtual_addr,
+            page as u64,
+            PAGE_SIZE as u64,
+            PTE_R | PTE_W,
+        );
     }
 
     pagetable
@@ -559,6 +569,36 @@ pub unsafe extern "C" fn copyin(
     0
 }
 
+// Copy to either a user address, or kernel address,
+// depending on usr_dst.
+// Returns 0 on success, -1 on error.
+#[no_mangle]
+pub unsafe extern "C" fn either_copyout(user_dst: i32, dst: u64, src: *mut u8, len: u64) -> i32 {
+    let p = Process::current().unwrap();
+
+    if user_dst > 0 {
+        copyout(p.pagetable, dst, src, len)
+    } else {
+        memmove(dst as *mut u8, src, len as u32);
+        0
+    }
+}
+
+// Copy from either a user address, or kernel address,
+// depending on usr_src.
+// Returns 0 on success, -1 on error.
+#[no_mangle]
+pub unsafe extern "C" fn either_copyin(dst: *mut u8, user_src: i32, src: u64, len: u64) -> i32 {
+    let p = Process::current().unwrap();
+
+    if user_src > 0 {
+        copyin(p.pagetable, dst, src, len)
+    } else {
+        memmove(dst, src as *mut u8, len as u32);
+        0
+    }
+}
+
 /// Copy a null-terminated string from user to kernel.
 ///
 /// Copy bytes to `dst` from virtual address `src_virtual_addr`
diff --git a/kernel/rustkernel/src/console/mod.rs b/kernel/rustkernel/src/console/mod.rs
index 27d7cb3..7414b6e 100644
--- a/kernel/rustkernel/src/console/mod.rs
+++ b/kernel/rustkernel/src/console/mod.rs
@@ -11,6 +11,7 @@
 pub mod printf;
 
 use crate::{
+    arch::virtual_memory::{either_copyin, either_copyout},
     fs::file::{devsw, CONSOLE},
     hardware::uart::Uart,
     proc::{
@@ -19,12 +20,7 @@ use crate::{
     },
     sync::mutex::Mutex,
 };
-use core::{ffi::c_void, ptr::addr_of_mut};
-
-extern "C" {
-    fn either_copyin(dst: *mut c_void, user_src: i32, src: u64, len: u64) -> i32;
-    fn either_copyout(user_dst: i32, dst: u64, src: *mut c_void, len: u64) -> i32;
-}
+use core::ptr::addr_of_mut;
 
 pub static UART0: &Uart = &crate::hardware::UARTS[0].1;