exec compiles but argstr() doesn't work yet

1 files changed, 50 insertions, 24 deletions

diff --git a/exec.c b/exec.c
index 6d0ef24..a9776bc 100644
--- a/exec.c
+++ b/exec.c
@@ -1,14 +1,13 @@
 #include "types.h"
 #include "param.h"
 #include "memlayout.h"
-#include "mmu.h"
+#include "riscv.h"
 #include "proc.h"
 #include "defs.h"
-#include "traps.h"
-#include "msr.h"
-#include "x86.h"
 #include "elf.h"
 
+static int loadseg(pde_t *pgdir, uint64 addr, struct inode *ip, uint offset, uint sz);
+
 int
 exec(char *path, char **argv)
 {
@@ -18,9 +17,11 @@ exec(char *path, char **argv)
   struct elfhdr elf;
   struct inode *ip;
   struct proghdr ph;
-  pde_t *pgdir, *oldpgdir;
+  pagetable_t pagetable = 0, oldpagetable;
   struct proc *p = myproc();
   uint64 oldsz = p->sz;
+
+  printf("EXEC\n");
   
   begin_op();
 
@@ -29,7 +30,6 @@ exec(char *path, char **argv)
     return -1;
   }
   ilock(ip);
-  pgdir = 0;
 
   // Check ELF header
   if(readi(ip, (char*)&elf, 0, sizeof(elf)) != sizeof(elf))
@@ -37,7 +37,7 @@ exec(char *path, char **argv)
   if(elf.magic != ELF_MAGIC)
     goto bad;
 
-  if((pgdir = setupkvm()) == 0)
+  if((pagetable = proc_pagetable(p)) == 0)
     goto bad;
 
   // Load program into memory.
@@ -51,11 +51,11 @@ exec(char *path, char **argv)
       goto bad;
     if(ph.vaddr + ph.memsz < ph.vaddr)
       goto bad;
-    if((sz = allocuvm(pgdir, sz, ph.vaddr + ph.memsz)) == 0)
+    if((sz = uvmalloc(pagetable, sz, ph.vaddr + ph.memsz)) == 0)
       goto bad;
     if(ph.vaddr % PGSIZE != 0)
       goto bad;
-    if(loaduvm(pgdir, (char*)ph.vaddr, ip, ph.off, ph.filesz) < 0)
+    if(loadseg(pagetable, ph.vaddr, ip, ph.off, ph.filesz) < 0)
       goto bad;
   }
   iunlockput(ip);
@@ -63,11 +63,10 @@ exec(char *path, char **argv)
   ip = 0;
 
   // Allocate two pages at the next page boundary.
-  // Make the first inaccessible.  Use the second as the user stack.
+  // Use the second as the user stack.
   sz = PGROUNDUP(sz);
-  if((sz = allocuvm(pgdir, sz, sz + 2*PGSIZE)) == 0)
+  if((sz = uvmalloc(pagetable, sz, sz + 2*PGSIZE)) == 0)
     goto bad;
-  clearpteu(pgdir, (char*)(sz - 2*PGSIZE));
   sp = sz;
 
   // Push argument strings, prepare rest of stack in ustack.
@@ -75,7 +74,7 @@ exec(char *path, char **argv)
     if(argc >= MAXARG)
       goto bad;
     sp = (sp - (strlen(argv[argc]) + 1)) & ~(sizeof(uint64)-1);
-    if(copyout(pgdir, sp, argv[argc], strlen(argv[argc]) + 1) < 0)
+    if(copyout(pagetable, sp, argv[argc], strlen(argv[argc]) + 1) < 0)
       goto bad;
     ustack[3+argc] = sp;
   }
@@ -85,11 +84,12 @@ exec(char *path, char **argv)
   ustack[1] = argc;
   ustack[2] = sp - (argc+1)*sizeof(uint64);  // argv pointer
 
-  p->sf->rdi = argc;
-  p->sf->rsi = sp - (argc+1)*sizeof(uint64);
+  // arguments to user main(argc, argv)
+  p->tf->a0 = argc;
+  p->tf->a1 = sp - (argc+1)*sizeof(uint64);
 
   sp -= (3+argc+1) * sizeof(uint64);
-  if(copyout(pgdir, sp, ustack, (3+argc+1)*sizeof(uint64)) < 0)
+  if(copyout(pagetable, sp, (char *)ustack, (3+argc+1)*sizeof(uint64)) < 0)
     goto bad;
 
   // Save program name for debugging.
@@ -99,21 +99,47 @@ exec(char *path, char **argv)
   safestrcpy(p->name, last, sizeof(p->name));
     
   // Commit to the user image.
-  oldpgdir = p->pgdir;
-  p->pgdir = pgdir;
+  oldpagetable = p->pagetable;
+  p->pagetable = pagetable;
   p->sz = sz;
-  p->sf->rcx = elf.entry;  // main
-  p->sf->rsp = sp;
-  switchuvm(p);
-  freevm(oldpgdir, oldsz);
+  p->tf->epc = elf.entry;  // initial program counter = main
+  p->tf->sp = sp; // initial stack pointer
+  proc_freepagetable(oldpagetable, oldsz);
   return 0;
 
  bad:
-  if(pgdir)
-    freevm(pgdir, sz);
+  if(pagetable)
+    proc_freepagetable(pagetable, sz);
   if(ip){
     iunlockput(ip);
     end_op();
   }
   return -1;
 }
+
+// Load a program segment into pagetable at virtual address va.
+// va must be page-aligned
+// and the pages from va to va+sz must already be mapped.
+// Returns 0 on success, -1 on failure.
+static int
+loadseg(pagetable_t pagetable, uint64 va, struct inode *ip, uint offset, uint sz)
+{
+  uint i, n;
+  uint64 pa;
+  pte_t *pte;
+
+  if((va % PGSIZE) != 0)
+    panic("loadseg: va must be page aligned");
+  for(i = 0; i < sz; i += PGSIZE){
+    pa = walkaddr(pagetable, va + i);
+    if(pa == 0)
+      panic("loadseg: address should exist");
+    if(sz - i < PGSIZE)
+      n = sz - i;
+    else
+      n = PGSIZE;
+    if(readi(ip, (char *)pa, offset+i, n) != n)
+      return -1;
+  }
+  return 0;
+}