[8/14,LoongArch] Linux Startup and Dynamic Loading Code
Commit Message
From 74fcaf6fef4f5e0780f7b25d08a9965fe500deb8 Mon Sep 17 00:00:00 2001
From: caiyinyu <caiyinyu@loongson.cn>
Date: Tue, 27 Jul 2021 15:59:12 +0800
Subject: [PATCH 08/14] LoongArch: Linux Startup and Dynamic Loading Code
This contains the Linux-specific code for loading programs on LoongArch.
* sysdeps/unix/sysv/linux/loongarch/dl-static.c: New file.
* sysdeps/unix/sysv/linux/loongarch/ldsodefs.h: Likewise.
---
sysdeps/unix/sysv/linux/loongarch/dl-static.c | 79 +++++++++++++++++++
sysdeps/unix/sysv/linux/loongarch/ldsodefs.h | 32 ++++++++
2 files changed, 111 insertions(+)
create mode 100644 sysdeps/unix/sysv/linux/loongarch/dl-static.c
create mode 100644 sysdeps/unix/sysv/linux/loongarch/ldsodefs.h
b/sysdeps/unix/sysv/linux/loongarch/dl-static.c
new file mode 100644
@@ -0,0 +1,79 @@
+/* Copyright (C) 2021 Free Software Foundation, Inc.
+
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library. If not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <ldsodefs.h>
+
+#ifdef SHARED
+
+void
+_dl_var_init (void *array[])
+{
+ /* It has to match "variables" below. */
+ enum
+ {
+ DL_PAGESIZE = 0
+ };
+
+ GLRO (dl_pagesize) = *((size_t *) array[DL_PAGESIZE]);
+}
+
+#else
+
+static void *variables[] = {&GLRO (dl_pagesize)};
+
+static void _dl_unprotect_relro (struct link_map *l)
+{
+ ElfW (Addr) start = ((l->l_addr + l->l_relro_addr)
+ & ~(GLRO (dl_pagesize) - 1));
+ ElfW (Addr) end = ((l->l_addr + l->l_relro_addr + l->l_relro_size)
+ & ~(GLRO (dl_pagesize) - 1));
+
+ if (start != end)
+ __mprotect ((void *) start, end - start, PROT_READ | PROT_WRITE);
+}
+
+void dl_static_init (struct link_map *l)
+{
+ struct link_map *rtld_map = l;
+ struct r_scope_elem **scope;
+ const ElfW (Sym) *ref = NULL;
+ lookup_t loadbase;
+ void (*f) (void *[]);
+ size_t i;
+
+ loadbase = _dl_lookup_symbol_x ("_dl_var_init", l, &ref, l->l_local_scope,
+ NULL, 0, 1, NULL);
+
+ for (scope = l->l_local_scope; *scope != NULL; scope++)
+ for (i = 0; i < (*scope)->r_nlist; i++)
+ if ((*scope)->r_list[i] == loadbase)
+ {
+ rtld_map = (*scope)->r_list[i];
+ break;
+ }
+
+ if (ref != NULL)
+ {
+ f = (void (*) (void *[])) DL_SYMBOL_ADDRESS (loadbase, ref);
+ _dl_unprotect_relro (rtld_map);
+ f (variables);
+ _dl_protect_relro (rtld_map);
+ }
+}
+
+#endif
b/sysdeps/unix/sysv/linux/loongarch/ldsodefs.h
new file mode 100644
@@ -0,0 +1,32 @@
+/* Copyright (C) 2021 Free Software Foundation, Inc.
+
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library. If not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _LDSODEFS_H
+
+/* Get the real definitions. */
+#include_next <ldsodefs.h>
+
+/* Now define our stuff. */
+
+/* We need special support to initialize DSO loaded for statically linked
+ binaries. */
+extern void _dl_static_init (struct link_map *map);
+#undef DL_STATIC_INIT
+#define DL_STATIC_INIT(map) _dl_static_init (map)
+
+#endif /* ldsodefs.h */