Move DRAM to high addresses

6 files changed, 40 insertions, 41 deletions

diff --git a/pk/file.c b/pk/file.c
index 9176f1a..53087c3 100644
--- a/pk/file.c
+++ b/pk/file.c
@@ -91,7 +91,7 @@ file_t* file_openat(int dirfd, const char* fn, int flags, int mode)
     return ERR_PTR(-ENOMEM);
 
   size_t fn_size = strlen(fn)+1;
-  long ret = frontend_syscall(SYS_openat, dirfd, (long)fn, fn_size, flags, mode, 0, 0);
+  long ret = frontend_syscall(SYS_openat, dirfd, va2pa(fn), fn_size, flags, mode, 0, 0);
   if (ret >= 0)
   {
     f->kfd = ret;
@@ -120,31 +120,31 @@ int fd_close(int fd)
 ssize_t file_read(file_t* f, void* buf, size_t size)
 {
   populate_mapping(buf, size, PROT_WRITE);
-  return frontend_syscall(SYS_read, f->kfd, (uintptr_t)buf, size, 0, 0, 0, 0);
+  return frontend_syscall(SYS_read, f->kfd, va2pa(buf), size, 0, 0, 0, 0);
 }
 
 ssize_t file_pread(file_t* f, void* buf, size_t size, off_t offset)
 {
   populate_mapping(buf, size, PROT_WRITE);
-  return frontend_syscall(SYS_pread, f->kfd, (uintptr_t)buf, size, offset, 0, 0, 0);
+  return frontend_syscall(SYS_pread, f->kfd, va2pa(buf), size, offset, 0, 0, 0);
 }
 
 ssize_t file_write(file_t* f, const void* buf, size_t size)
 {
   populate_mapping(buf, size, PROT_READ);
-  return frontend_syscall(SYS_write, f->kfd, (uintptr_t)buf, size, 0, 0, 0, 0);
+  return frontend_syscall(SYS_write, f->kfd, va2pa(buf), size, 0, 0, 0, 0);
 }
 
 ssize_t file_pwrite(file_t* f, const void* buf, size_t size, off_t offset)
 {
   populate_mapping(buf, size, PROT_READ);
-  return frontend_syscall(SYS_pwrite, f->kfd, (uintptr_t)buf, size, offset, 0, 0, 0);
+  return frontend_syscall(SYS_pwrite, f->kfd, va2pa(buf), size, offset, 0, 0, 0);
 }
 
 int file_stat(file_t* f, struct stat* s)
 {
   struct frontend_stat buf;
-  long ret = frontend_syscall(SYS_fstat, f->kfd, (uintptr_t)&buf, 0, 0, 0, 0, 0);
+  long ret = frontend_syscall(SYS_fstat, f->kfd, va2pa(&buf), 0, 0, 0, 0, 0);
   copy_stat(s, &buf);
   return ret;
 }
diff --git a/pk/mmap.c b/pk/mmap.c
index 2f6a202..9f886ed 100644
--- a/pk/mmap.c
+++ b/pk/mmap.c
@@ -85,26 +85,21 @@ static size_t pt_idx(uintptr_t addr, int level)
   return idx & ((1 << RISCV_PGLEVEL_BITS) - 1);
 }
 
-static pte_t* __maybe_create_root_page_table()
+static pte_t* __walk_create(uintptr_t addr);
+
+static pte_t* __attribute__((noinline)) __continue_walk_create(uintptr_t addr, pte_t* pte)
 {
-  if (!root_page_table)
-    root_page_table = (void*)__page_alloc();
-  return root_page_table;
+  *pte = ptd_create(ppn(__page_alloc()));
+  return __walk_create(addr);
 }
 
 static pte_t* __walk_internal(uintptr_t addr, int create)
 {
-  pte_t* t = __maybe_create_root_page_table();
+  pte_t* t = root_page_table;
   for (int i = (VA_BITS - RISCV_PGSHIFT) / RISCV_PGLEVEL_BITS - 1; i > 0; i--) {
     size_t idx = pt_idx(addr, i);
-    if (!(t[idx] & PTE_V)) {
-      if (!create)
-        return 0;
-      uintptr_t page = __page_alloc();
-      t[idx] = ptd_create(ppn(page));
-    }
-    else
-      kassert(PTE_TABLE(t[idx]));
+    if (unlikely(!(t[idx] & PTE_V)))
+      return create ? __continue_walk_create(addr, &t[idx]) : 0;
     t = (pte_t*)(pte_ppn(t[idx]) << RISCV_PGSHIFT);
   }
   return &t[pt_idx(addr, 0)];
@@ -176,7 +171,7 @@ int __valid_user_range(uintptr_t vaddr, size_t len)
 {
   if (vaddr + len < vaddr)
     return 0;
-  return vaddr >= first_free_paddr && vaddr + len <= current.mmap_max;
+  return vaddr + len <= current.mmap_max;
 }
 
 static int __handle_page_fault(uintptr_t vaddr, int prot)
@@ -190,7 +185,7 @@ static int __handle_page_fault(uintptr_t vaddr, int prot)
     return -1;
   else if (!(*pte & PTE_V))
   {
-    uintptr_t ppn = vpn;
+    uintptr_t ppn = vpn + (first_free_paddr / RISCV_PGSIZE);
 
     vmr_t* v = (vmr_t*)*pte;
     *pte = pte_create(ppn, prot_to_type(PROT_READ|PROT_WRITE, 0));
@@ -407,16 +402,16 @@ uintptr_t pk_vm_init()
 {
   size_t mem_pages = mem_size >> RISCV_PGSHIFT;
   free_pages = MAX(8, mem_pages >> (RISCV_PGLEVEL_BITS-1));
-  first_free_page = mem_size - free_pages * RISCV_PGSIZE;
+  first_free_page = first_free_paddr;
+  first_free_paddr += free_pages * RISCV_PGSIZE;
 
-  __map_kernel_range(0, 0, first_free_paddr, PROT_READ|PROT_WRITE|PROT_EXEC);
-  __map_kernel_range(first_free_page, first_free_page, free_pages * RISCV_PGSIZE, PROT_READ|PROT_WRITE);
+  root_page_table = (void*)__page_alloc();
+  __map_kernel_range(DRAM_BASE, DRAM_BASE, first_free_paddr - DRAM_BASE, PROT_READ|PROT_WRITE|PROT_EXEC);
 
-  // keep user addresses positive
-  current.mmap_max = MIN(first_free_page, (uintptr_t)INTPTR_MAX + 1);
-  current.brk_max = current.mmap_max;
+  current.mmap_max = current.brk_max =
+    MIN(DRAM_BASE, mem_size - (first_free_paddr - DRAM_BASE));
 
-  size_t stack_size = RISCV_PGSIZE * CLAMP(mem_size/(RISCV_PGSIZE*32), 1, 256);
+  size_t stack_size = RISCV_PGSIZE * 64;
   size_t stack_bottom = __do_mmap(current.mmap_max - stack_size, stack_size, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED, 0, 0);
   kassert(stack_bottom != (uintptr_t)-1);
   current.stack_top = stack_bottom + stack_size;
diff --git a/pk/mmap.h b/pk/mmap.h
index e3c2035..3fc3186 100644
--- a/pk/mmap.h
+++ b/pk/mmap.h
@@ -5,6 +5,7 @@
 #include "syscall.h"
 #include "encoding.h"
 #include "file.h"
+#include "mtrap.h"
 #include <stddef.h>
 
 #define PROT_NONE 0
@@ -31,4 +32,7 @@ uintptr_t do_mremap(uintptr_t addr, size_t old_size, size_t new_size, int flags)
 uintptr_t do_mprotect(uintptr_t addr, size_t length, int prot);
 uintptr_t do_brk(uintptr_t addr);
 
+#define va2pa(va) ({ uintptr_t __va = (uintptr_t)(va); \
+  __va >= DRAM_BASE ? __va : __va + first_free_paddr; })
+
 #endif
diff --git a/pk/pk.c b/pk/pk.c
index 6878811..ab2e119 100644
--- a/pk/pk.c
+++ b/pk/pk.c
@@ -70,7 +70,7 @@ typedef union {
 
 static size_t parse_args(arg_buf* args)
 {
-  long r = frontend_syscall(SYS_getmainvars, (uintptr_t)args, sizeof(*args), 0, 0, 0, 0, 0);
+  long r = frontend_syscall(SYS_getmainvars, va2pa(args), sizeof(*args), 0, 0, 0, 0, 0);
   kassert(r == 0);
   uint64_t* pk_argv = &args->buf[1];
   // pk_argv[0] is the proxy kernel itself.  skip it and any flags.
diff --git a/pk/pk.lds b/pk/pk.lds
index 0897e50..522e4a8 100644
--- a/pk/pk.lds
+++ b/pk/pk.lds
@@ -10,7 +10,7 @@ SECTIONS
   /*--------------------------------------------------------------------*/
 
   /* Begining of code and text segment */
-  . = 0;
+  . = 0x80000000;
   _ftext = .;
   PROVIDE( eprol = . );
 
diff --git a/pk/syscall.c b/pk/syscall.c
index 1c9e234..9f2be88 100644
--- a/pk/syscall.c
+++ b/pk/syscall.c
@@ -111,8 +111,8 @@ int sys_renameat(int old_fd, const char *old_path, int new_fd, const char *new_p
   if(old_kfd != -1 && new_kfd != -1) {
     size_t old_size = strlen(old_path)+1;
     size_t new_size = strlen(new_path)+1;
-    return frontend_syscall(SYS_renameat, old_kfd, (uintptr_t)old_path, old_size,
-                                           new_kfd, (uintptr_t)new_path, new_size, 0);
+    return frontend_syscall(SYS_renameat, old_kfd, va2pa(old_path), old_size,
+                                           new_kfd, va2pa(new_path), new_size, 0);
   }
   return -EBADF;
 }
@@ -191,7 +191,7 @@ long sys_lstat(const char* name, void* st)
 {
   struct frontend_stat buf;
   size_t name_size = strlen(name)+1;
-  long ret = frontend_syscall(SYS_lstat, (uintptr_t)name, name_size, (uintptr_t)&buf, 0, 0, 0, 0);
+  long ret = frontend_syscall(SYS_lstat, va2pa(name), name_size, va2pa(&buf), 0, 0, 0, 0);
   copy_stat(st, &buf);
   return ret;
 }
@@ -202,7 +202,7 @@ long sys_fstatat(int dirfd, const char* name, void* st, int flags)
   if (kfd != -1) {
     struct frontend_stat buf;
     size_t name_size = strlen(name)+1;
-    long ret = frontend_syscall(SYS_fstatat, kfd, (uintptr_t)name, name_size, (uintptr_t)&buf, flags, 0, 0);
+    long ret = frontend_syscall(SYS_fstatat, kfd, va2pa(name), name_size, va2pa(&buf), flags, 0, 0);
     copy_stat(st, &buf);
     return ret;
   }
@@ -219,7 +219,7 @@ long sys_faccessat(int dirfd, const char *name, int mode)
   int kfd = at_kfd(dirfd);
   if (kfd != -1) {
     size_t name_size = strlen(name)+1;
-    return frontend_syscall(SYS_faccessat, kfd, (uintptr_t)name, name_size, mode, 0, 0, 0);
+    return frontend_syscall(SYS_faccessat, kfd, va2pa(name), name_size, mode, 0, 0, 0);
   }
   return -EBADF;
 }
@@ -236,8 +236,8 @@ long sys_linkat(int old_dirfd, const char* old_name, int new_dirfd, const char*
   if (old_kfd != -1 && new_kfd != -1) {
     size_t old_size = strlen(old_name)+1;
     size_t new_size = strlen(new_name)+1;
-    return frontend_syscall(SYS_linkat, old_kfd, (uintptr_t)old_name, old_size,
-                                        new_kfd, (uintptr_t)new_name, new_size,
+    return frontend_syscall(SYS_linkat, old_kfd, va2pa(old_name), old_size,
+                                        new_kfd, va2pa(new_name), new_size,
                                         flags);
   }
   return -EBADF;
@@ -253,7 +253,7 @@ long sys_unlinkat(int dirfd, const char* name, int flags)
   int kfd = at_kfd(dirfd);
   if (kfd != -1) {
     size_t name_size = strlen(name)+1;
-    return frontend_syscall(SYS_unlinkat, kfd, (uintptr_t)name, name_size, flags, 0, 0, 0);
+    return frontend_syscall(SYS_unlinkat, kfd, va2pa(name), name_size, flags, 0, 0, 0);
   }
   return -EBADF;
 }
@@ -268,7 +268,7 @@ long sys_mkdirat(int dirfd, const char* name, int mode)
   int kfd = at_kfd(dirfd);
   if (kfd != -1) {
     size_t name_size = strlen(name)+1;
-    return frontend_syscall(SYS_mkdirat, kfd, (uintptr_t)name, name_size, mode, 0, 0, 0);
+    return frontend_syscall(SYS_mkdirat, kfd, va2pa(name), name_size, mode, 0, 0, 0);
   }
   return -EBADF;
 }
@@ -281,7 +281,7 @@ long sys_mkdir(const char* name, int mode)
 long sys_getcwd(const char* buf, size_t size)
 {
   populate_mapping(buf, size, PROT_WRITE);
-  return frontend_syscall(SYS_getcwd, (uintptr_t)buf, size, 0, 0, 0, 0, 0);
+  return frontend_syscall(SYS_getcwd, va2pa(buf), size, 0, 0, 0, 0, 0);
 }
 
 size_t sys_brk(size_t pos)
@@ -384,7 +384,7 @@ ssize_t sys_writev(int fd, const long* iov, int cnt)
 
 int sys_chdir(const char *path)
 {
-  return frontend_syscall(SYS_chdir, (uintptr_t)path, 0, 0, 0, 0, 0, 0);
+  return frontend_syscall(SYS_chdir, va2pa(path), 0, 0, 0, 0, 0, 0);
 }
 
 int sys_getdents(int fd, void* dirbuf, int count)