uaccess clean up

4ec2e3db · Silas Boyd-Wickizer · ae8f1bcf · 4ec2e3db · 4ec2e3db · 4ec2e3db
--- a/include/kernel.hh
+++ b/include/kernel.hh
@@ -205,9 +205,9 @@ void            release(struct spinlock*);
 int             argcheckptr(void *argval, int);
 int             argcheckstr(const char*);
 int             fetchint64(uptr, u64*);
-int             fetchstr(char*, const char*, unsigned);
+int             fetchstr(char*, const char*, u64);
-int             umemcpy(void*, void*, u64);
+int             fetchmem(void*, const void*, u64);
-int             kmemcpy(void*, void*, u64);
+int             putmem(void*, const void*, u64);
 u64             syscall(u64 a0, u64 a1, u64 a2, u64 a3, u64 a4, u64 num);
 // string.c

--- a/kernel/net.cc
+++ b/kernel/net.cc
@@ -282,7 +282,7 @@ netbind(int sock, void *xaddr, int xaddrlen)
  if (addr == nullptr)
    return -1;
-  if (umemcpy(addr, xaddr, xaddrlen))
+  if (fetchmem(addr, xaddr, xaddrlen))
    return -1;
  lwip_core_lock();
@@ -311,7 +311,7 @@ netaccept(int sock, void *xaddr, void *xaddrlen)
  void *addr;
  int ss;
-  if (umemcpy(&len, lenptr, sizeof(*lenptr)))
+  if (fetchmem(&len, lenptr, sizeof(*lenptr)))
    return -1;
  addr = kmalloc(len, "sockaddr");
@@ -326,7 +326,7 @@ netaccept(int sock, void *xaddr, void *xaddrlen)
    return ss;
  }
-  if (kmemcpy(xaddrlen, &len, sizeof(len)) || kmemcpy(xaddr, addr, len)) {
+  if (putmem(xaddrlen, &len, sizeof(len)) || putmem(xaddr, addr, len)) {
    lwip_core_lock();
    lwip_close(ss);
    lwip_core_unlock();
@@ -357,7 +357,7 @@ netwrite(int sock, char *ubuf, int len)
    return -1;
  cc = MIN(len, PGSIZE);
-  if (umemcpy(kbuf, ubuf, cc)) {
+  if (fetchmem(kbuf, ubuf, cc)) {
    kfree(kbuf);
    return -1;
  }
@@ -388,7 +388,7 @@ netread(int sock, char *ubuf, int len)
    return r;
  }
-  kmemcpy(ubuf, kbuf, r);
+  putmem(ubuf, kbuf, r);
  kfree(kbuf);
  return r;
 }

--- a/kernel/syscall.cc
+++ b/kernel/syscall.cc
@@ -10,15 +10,32 @@
 #include "cpu.hh"
 #include "kmtrace.hh"
-extern "C" int __fetchstr(char* dst, const char* usrc, unsigned size);
+extern "C" int __uaccess_mem(void* dst, const void* src, u64 size);
-extern "C" int __fetchint64(uptr addr, u64* ip);
+extern "C" int __uaccess_str(char* dst, const char* src, u64 size);
+extern "C" int __uaccess_int64(uptr addr, u64* ip);
 int
-fetchstr(char* dst, const char* usrc, unsigned size)
+fetchmem(void* dst, const void* usrc, u64 size)
 {
  if(mycpu()->ncli != 0)
    panic("fetchstr: cli'd");
-  return __fetchstr(dst, usrc, size);
+  return __uaccess_mem(dst, usrc, size);
+}
+int
+putmem(void *udst, const void *src, u64 size)
+{
+  if(mycpu()->ncli != 0)
+    panic("fetchstr: cli'd");
+  return __uaccess_mem(udst, src, size);
+}
+int
+fetchstr(char* dst, const char* usrc, u64 size)
+{
+  if(mycpu()->ncli != 0)
+    panic("fetchstr: cli'd");
+  return __uaccess_str(dst, usrc, size);
 }
 int
@@ -26,7 +43,7 @@ fetchint64(uptr addr, u64 *ip)
 {
  if(mycpu()->ncli != 0)
    panic("fetchstr: cli'd");
-  return __fetchint64(addr, ip);
+  return __uaccess_int64(addr, ip);
 }
 // Fetch the nul-terminated string at addr from process p.
@@ -60,43 +77,6 @@ argcheckptr(void *p, int size)
  return 0;
 }
-static int
-umemptr(void *umem, void **ret, u64 size)
-{
-  uptr ptr = (uptr) umem;
-  for(uptr va = PGROUNDDOWN(ptr); va < ptr+size; va = va + PGSIZE)
-    if(pagefault(myproc()->vmap, va, 0) < 0)
-      return -1;
-  *ret = umem;
-  return 0;
-}
-int
-umemcpy(void *dst, void *umem, u64 size)
-{
-  void *ptr;
-  if (umemptr(umem, &ptr, size))
-    return -1;
-  memmove(dst, ptr, size);
-  return 0;
-}
-int
-kmemcpy(void *umem, void *src, u64 size)
-{
-  void *ptr;
-  if (umemptr(umem, &ptr, size))
-    return -1;
-  memmove(ptr, src, size);
-  return 0;
-}
 u64
 syscall(u64 a0, u64 a1, u64 a2, u64 a3, u64 a4, u64 num)
 {

--- a/kernel/trap.cc
+++ b/kernel/trap.cc
@@ -12,7 +12,7 @@
 #include "bits.hh"
 #include "kalloc.hh"
-extern "C" void __fetch_end(void);
+extern "C" void __uaccess_end(void);
 struct intdesc idt[256] __attribute__((aligned(16)));
@@ -60,7 +60,7 @@ do_pagefault(struct trapframe *tf)
    }
    cprintf("pagefault: failed in kernel\n");
    tf->rax = -1;
-    tf->rip = (u64)__fetch_end;
+    tf->rip = (u64)__uaccess_end;
    return 0;
  } else if (tf->err & FEC_U) {
      sti();

--- a/kernel/uaccess.S
+++ b/kernel/uaccess.S
 #include "mmu.h"
 #include "asmdefines.h"
+#define ENTRY(name) .globl name ; .align 8; name :
+// We aren't allowed to touch rbx,rsp,rbp,r12-r15
 .code64
-.globl __fetchint64
-.align 8
 // rdi user src
 // rsi kernel dst
-// We aren't allowed to touch rbx,rsp,rbp,r12-r15
+ENTRY(__uaccess_int64)
-__fetchint64:
        mov     %gs:0x8, %r11
        movl    $1, PROC_UACCESS(%r11)
        mov     (%rdi), %r10
        mov     %r10, (%rsi)
        mov     $0, %rax
-        jmp     __fetch_end
+        jmp     __uaccess_end
-.globl __fetchstr
+// rdi dst
-.align 8
+// rsi src
-// rdi kernel dst
+// rdx dst len
-// rsi user src
+ENTRY(__uaccess_str)
-// rdx kernel len
-// We aren't allowed to touch rbx,rsp,rbp,r12-r15
-__fetchstr:
        mov     %gs:0x8, %r11
        movl    $1, PROC_UACCESS(%r11)
@@ -40,11 +38,30 @@ __fetchstr:
        // Error
        movq    $-1, %rax
 2:      // Done
-        jmp     __fetch_end
+        jmp     __uaccess_end
+// rdi dst
+// rsi src
+// rdx len
+ENTRY(__uaccess_mem)
+        mov     %gs:0x8, %r11
+        movl    $1, PROC_UACCESS(%r11)
-.globl __fetch_end
+        // %rcx is loop instruction counter
+        mov     %rdx, %rcx
+        xor     %rax, %rax
+1:   
+        movb    (%rsi), %r10b
+        movb    %r10b, (%rdi)
+        inc     %rdi
+        inc     %rsi
+        loop    1b
+        // Done
+        jmp     __uaccess_end
+.globl __uaccess_end
 .align 8
-__fetch_end:
+__uaccess_end:
        movl $0, PROC_UACCESS(%r11)
        ret