Add "--with-max-memory-bytes", to limit the used memorymaxmem

I have no idea if this works, but it does at least compile.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>

4 files changed, 40 insertions, 14 deletions

diff --git a/config.h.in b/config.h.in
index dbacd78..fa453f2 100644
--- a/config.h.in
+++ b/config.h.in
@@ -12,6 +12,9 @@
 /* Define if subproject MCPPBS_SPROJ_NORM is enabled */
 #undef MACHINE_ENABLED
 
+/* Maximum bytes of memory */
+#undef MAX_MEMORY_BYTES
+
 /* Define to the address where bug reports for this package should be sent. */
 #undef PACKAGE_BUGREPORT
 
diff --git a/configure b/configure
index b001ba3..e1beee1 100755
--- a/configure
+++ b/configure
@@ -646,7 +646,6 @@ infodir
 docdir
 oldincludedir
 includedir
-runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -672,6 +671,7 @@ enable_option_checking
 enable_stow
 with_arch
 enable_print_device_tree
+with_max_memory_bytes
 enable_optional_subprojects
 enable_vm
 enable_logo
@@ -733,7 +733,6 @@ datadir='${datarootdir}'
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
-runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -986,15 +985,6 @@ do
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
-  -runstatedir | --runstatedir | --runstatedi | --runstated \
-  | --runstate | --runstat | --runsta | --runst | --runs \
-  | --run | --ru | --r)
-    ac_prev=runstatedir ;;
-  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
-  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
-  | --run=* | --ru=* | --r=*)
-    runstatedir=$ac_optarg ;;
-
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1132,7 +1122,7 @@ fi
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir runstatedir
+		libdir localedir mandir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1285,7 +1275,6 @@ Fine tuning of the installation directories:
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
-  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -1333,6 +1322,7 @@ Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
   --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
   --with-arch             Set the RISC-V architecture
+  --with-max-memory-bytes Limit the maximum availiable memory
   --with-payload          Set ELF payload for bbl
   --with-logo             Specify a better logo
 
@@ -4095,6 +4085,20 @@ $as_echo "#define PK_PRINT_DEVICE_TREE /**/" >>confdefs.h
 
 fi
 
+
+# Check whether --with-max-memory-bytes was given.
+if test "${with_max_memory_bytes+set}" = set; then :
+  withval=$with_max_memory_bytes;
+fi
+
+if test "x$with_max_memory_bytes" != "xno"; then :
+
+
+$as_echo "#define MAX_MEMORY_BYTES \"\$with_max_memory_bytes\"" >>confdefs.h
+
+
+fi
+
 CFLAGS="-Wall -Werror -D__NO_INLINE__ -mcmodel=medany -O2 -std=gnu99 -Wno-unused -Wno-attributes -fno-delete-null-pointer-checks -fno-PIE"
 LDFLAGS="$LDFLAGS -Wl,--build-id=none"
 
diff --git a/configure.ac b/configure.ac
index 917179f..f482ae9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -88,6 +88,11 @@ AS_IF([test "x$enable_print_device_tree" == "xyes"], [
   AC_DEFINE([PK_PRINT_DEVICE_TREE],,[Define if the DTS is to be displayed])
 ])
 
+AC_ARG_WITH([max-memory-bytes], AS_HELP_STRING([--with-max-memory-bytes], [Limit the maximum availiable memory]))
+AS_IF([test "x$with_max_memory_bytes" != "xno"], [
+  AC_DEFINE([MAX_MEMORY_BYTES],"$with_max_memory_bytes",[Maximum bytes of memory])
+])
+
 CFLAGS="-Wall -Werror -D__NO_INLINE__ -mcmodel=medany -O2 -std=gnu99 -Wno-unused -Wno-attributes -fno-delete-null-pointer-checks -fno-PIE"
 LDFLAGS="$LDFLAGS -Wl,--build-id=none"
 
diff --git a/machine/fdt.c b/machine/fdt.c
index e8a504f..ba94b8d 100644
--- a/machine/fdt.c
+++ b/machine/fdt.c
@@ -126,6 +126,15 @@ const uint32_t *fdt_get_size(const struct fdt_scan_node *node, const uint32_t *v
   return value;
 }
 
+const uint32_t *fdt_set_size(const struct fdt_scan_node *node, uint32_t *value, uint64_t new_value)
+{
+  for (int cells = node->size_cells; cells > 0; --cells) {
+    *value++ = new_value;
+    new_value >>= 32;
+  }
+  return value;
+}
+
 int fdt_string_list_index(const struct fdt_scan_prop *prop, const char *str)
 {
   const char *list = (const char *)prop->value;
@@ -176,9 +185,14 @@ static void mem_done(const struct fdt_scan_node *node, void *extra)
 
   while (end - value > 0) {
     uint64_t base, size;
-    value = fdt_get_address(node->parent, value, &base);
+    const uint32_t *size_ptr;
+    size_ptr = value = fdt_get_address(node->parent, value, &base);
     value = fdt_get_size   (node->parent, value, &size);
     if (base <= self && self <= base + size) { mem_size = size; }
+#ifdef MAX_MEMORY_BYTES
+    if (size > (uintptr_t)(MAX_MEMORY_BYTES))
+      fdt_set_size(node->parent, (uint32_t *)size_ptr, (uintptr_t)(MAX_MEMORY_BYTES));
+#endif
   }
   assert (end == value);
 }