[PATCH v3 22/33] nds32: Loadable modules
From: Greentime Hu
Date: Fri Dec 08 2017 - 04:41:23 EST
From: Greentime Hu <greentime@xxxxxxxxxxxxx>
This patch adds support for loadable modules.
Signed-off-by: Vincent Chen <vincentc@xxxxxxxxxxxxx>
Signed-off-by: Greentime Hu <greentime@xxxxxxxxxxxxx>
---
arch/nds32/include/asm/module.h | 24 ++++
arch/nds32/kernel/module.c | 299 +++++++++++++++++++++++++++++++++++++++
2 files changed, 323 insertions(+)
create mode 100644 arch/nds32/include/asm/module.h
create mode 100644 arch/nds32/kernel/module.c
diff --git a/arch/nds32/include/asm/module.h b/arch/nds32/include/asm/module.h
new file mode 100644
index 0000000..5ed2b75
--- /dev/null
+++ b/arch/nds32/include/asm/module.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2005-2017 Andes Technology Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _ASM_NDS32_MODULE_H
+#define _ASM_NDS32_MODULE_H
+
+#include <asm-generic/module.h>
+
+#define MODULE_ARCH_VERMAGIC "NDS32v3"
+
+#endif /* _ASM_NDS32_MODULE_H */
diff --git a/arch/nds32/kernel/module.c b/arch/nds32/kernel/module.c
new file mode 100644
index 0000000..bb34e23
--- /dev/null
+++ b/arch/nds32/kernel/module.c
@@ -0,0 +1,299 @@
+/*
+ * Copyright (C) 2005-2017 Andes Technology Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+
+#include <asm/pgtable.h>
+
+void *module_alloc(unsigned long size)
+{
+ return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
+ GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
+ __builtin_return_address(0));
+}
+
+void module_free(struct module *module, void *region)
+{
+ vfree(region);
+}
+
+int module_frob_arch_sections(Elf_Ehdr * hdr,
+ Elf_Shdr * sechdrs,
+ char *secstrings, struct module *mod)
+{
+ return 0;
+}
+
+void do_reloc16(unsigned int val, unsigned int *loc, unsigned int val_mask,
+ unsigned int val_shift, unsigned int loc_mask,
+ unsigned int partial_in_place, unsigned int swap)
+{
+ unsigned int tmp = 0, tmp2 = 0;
+
+ __asm__ __volatile__("\tlhi.bi\t%0, [%2], 0\n"
+ "\tbeqz\t%3, 1f\n"
+ "\twsbh\t%0, %1\n"
+ "1:\n":"=r"(tmp):"0"(tmp), "r"(loc), "r"(swap)
+ );
+
+ tmp2 = tmp & loc_mask;
+ if (partial_in_place) {
+ tmp &= (!loc_mask);
+ tmp =
+ tmp2 | ((tmp + ((val & val_mask) >> val_shift)) & val_mask);
+ } else {
+ tmp = tmp2 | ((val & val_mask) >> val_shift);
+ }
+
+ __asm__ __volatile__("\tbeqz\t%3, 2f\n"
+ "\twsbh\t%0, %1\n"
+ "2:\n"
+ "\tshi.bi\t%0, [%2], 0\n":"=r"(tmp):"0"(tmp),
+ "r"(loc), "r"(swap)
+ );
+}
+
+void do_reloc32(unsigned int val, unsigned int *loc, unsigned int val_mask,
+ unsigned int val_shift, unsigned int loc_mask,
+ unsigned int partial_in_place, unsigned int swap)
+{
+ unsigned int tmp = 0, tmp2 = 0;
+
+ __asm__ __volatile__("\tlmw.bi\t%0, [%2], %0, 0\n"
+ "\tbeqz\t%3, 1f\n"
+ "\twsbh\t%0, %1\n"
+ "\trotri\t%0, %1, 16\n"
+ "1:\n":"=r"(tmp):"0"(tmp), "r"(loc), "r"(swap)
+ );
+
+ tmp2 = tmp & loc_mask;
+ if (partial_in_place) {
+ tmp &= (!loc_mask);
+ tmp =
+ tmp2 | ((tmp + ((val & val_mask) >> val_shift)) & val_mask);
+ } else {
+ tmp = tmp2 | ((val & val_mask) >> val_shift);
+ }
+
+ __asm__ __volatile__("\tbeqz\t%3, 2f\n"
+ "\twsbh\t%0, %1\n"
+ "\trotri\t%0, %1, 16\n"
+ "2:\n"
+ "\tsmw.bi\t%0, [%2], %0, 0\n":"=r"(tmp):"0"(tmp),
+ "r"(loc), "r"(swap)
+ );
+}
+
+static inline int exceed_limit(int offset, unsigned int val_mask,
+ struct module *module, Elf32_Rela * rel,
+ unsigned int relindex, unsigned int reloc_order)
+{
+ int abs_off = offset < 0 ? ~offset : offset;
+
+ if (abs_off & (~val_mask)) {
+ pr_err("\n%s: relocation type %d out of range.\n"
+ "please rebuild the kernel module with gcc option \"-Wa,-mno-small-text\".\n",
+ module->name, ELF32_R_TYPE(rel->r_info));
+ pr_err("section %d reloc %d offset 0x%x relative 0x%x.\n",
+ relindex, reloc_order, rel->r_offset, offset);
+ return true;
+ }
+ return false;
+}
+
+#ifdef __NDS32_EL__
+#define NEED_SWAP 1
+#else
+#define NEED_SWAP 0
+#endif
+
+int
+apply_relocate_add(Elf32_Shdr * sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relindex,
+ struct module *module)
+{
+ Elf32_Shdr *symsec = sechdrs + symindex;
+ Elf32_Shdr *relsec = sechdrs + relindex;
+ Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
+ Elf32_Rela *rel = (void *)relsec->sh_addr;
+ unsigned int i;
+
+ for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rela); i++, rel++) {
+ Elf32_Addr *loc;
+ Elf32_Sym *sym;
+ Elf32_Addr v;
+ s32 offset;
+
+ offset = ELF32_R_SYM(rel->r_info);
+ if (offset < 0
+ || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
+ pr_err("%s: bad relocation\n", module->name);
+ pr_err("section %d reloc %d\n", relindex, i);
+ return -ENOEXEC;
+ }
+
+ sym = ((Elf32_Sym *) symsec->sh_addr) + offset;
+
+ if (rel->r_offset < 0
+ || rel->r_offset > dstsec->sh_size - sizeof(u16)) {
+ pr_err("%s: out of bounds relocation\n", module->name);
+ pr_err("section %d reloc %d offset 0x%0x size %d\n",
+ relindex, i, rel->r_offset, dstsec->sh_size);
+ return -ENOEXEC;
+ }
+
+ loc = (Elf32_Addr *) (dstsec->sh_addr + rel->r_offset);
+ v = sym->st_value + rel->r_addend;
+
+ switch (ELF32_R_TYPE(rel->r_info)) {
+ case R_NDS32_NONE:
+ case R_NDS32_INSN16:
+ case R_NDS32_LABEL:
+ case R_NDS32_LONGCALL1:
+ case R_NDS32_LONGCALL2:
+ case R_NDS32_LONGCALL3:
+ case R_NDS32_LONGCALL4:
+ case R_NDS32_LONGJUMP1:
+ case R_NDS32_LONGJUMP2:
+ case R_NDS32_LONGJUMP3:
+ case R_NDS32_9_FIXED_RELA:
+ case R_NDS32_15_FIXED_RELA:
+ case R_NDS32_17_FIXED_RELA:
+ case R_NDS32_25_FIXED_RELA:
+ case R_NDS32_LOADSTORE:
+ case R_NDS32_DWARF2_OP1_RELA:
+ case R_NDS32_DWARF2_OP2_RELA:
+ case R_NDS32_DWARF2_LEB_RELA:
+ case R_NDS32_RELA_NOP_MIX ... R_NDS32_RELA_NOP_MAX:
+ break;
+
+ case R_NDS32_32_RELA:
+ do_reloc32(v, loc, 0xffffffff, 0, 0, 0, 0);
+ break;
+
+ case R_NDS32_HI20_RELA:
+ do_reloc32(v, loc, 0xfffff000, 12, 0xfff00000, 0,
+ NEED_SWAP);
+ break;
+
+ case R_NDS32_LO12S3_RELA:
+ do_reloc32(v, loc, 0x00000fff, 3, 0xfffff000, 0,
+ NEED_SWAP);
+ break;
+
+ case R_NDS32_LO12S2_RELA:
+ do_reloc32(v, loc, 0x00000fff, 2, 0xfffff000, 0,
+ NEED_SWAP);
+ break;
+
+ case R_NDS32_LO12S1_RELA:
+ do_reloc32(v, loc, 0x00000fff, 1, 0xfffff000, 0,
+ NEED_SWAP);
+ break;
+
+ case R_NDS32_LO12S0_RELA:
+ case R_NDS32_LO12S0_ORI_RELA:
+ do_reloc32(v, loc, 0x00000fff, 0, 0xfffff000, 0,
+ NEED_SWAP);
+ break;
+
+ case R_NDS32_9_PCREL_RELA:
+ if (exceed_limit
+ ((v - (Elf32_Addr) loc), 0x000000ff, module, rel,
+ relindex, i))
+ return -ENOEXEC;
+ do_reloc16(v - (Elf32_Addr) loc, loc, 0x000001ff, 1,
+ 0xffffff00, 0, NEED_SWAP);
+ break;
+
+ case R_NDS32_15_PCREL_RELA:
+ if (exceed_limit
+ ((v - (Elf32_Addr) loc), 0x00003fff, module, rel,
+ relindex, i))
+ return -ENOEXEC;
+ do_reloc32(v - (Elf32_Addr) loc, loc, 0x00007fff, 1,
+ 0xffffc000, 0, NEED_SWAP);
+ break;
+
+ case R_NDS32_17_PCREL_RELA:
+ if (exceed_limit
+ ((v - (Elf32_Addr) loc), 0x0000ffff, module, rel,
+ relindex, i))
+ return -ENOEXEC;
+ do_reloc32(v - (Elf32_Addr) loc, loc, 0x0001ffff, 1,
+ 0xffff0000, 0, NEED_SWAP);
+ break;
+
+ case R_NDS32_25_PCREL_RELA:
+ if (exceed_limit
+ ((v - (Elf32_Addr) loc), 0x00ffffff, module, rel,
+ relindex, i))
+ return -ENOEXEC;
+ do_reloc32(v - (Elf32_Addr) loc, loc, 0x01ffffff, 1,
+ 0xff000000, 0, NEED_SWAP);
+ break;
+ case R_NDS32_WORD_9_PCREL_RELA:
+ if (exceed_limit
+ ((v - (Elf32_Addr) loc), 0x000000ff, module, rel,
+ relindex, i))
+ return -ENOEXEC;
+ do_reloc32(v - (Elf32_Addr) loc, loc, 0x000001ff, 1,
+ 0xffffff00, 0, NEED_SWAP);
+ break;
+
+ case R_NDS32_SDA15S3_RELA:
+ case R_NDS32_SDA15S2_RELA:
+ case R_NDS32_SDA15S1_RELA:
+ case R_NDS32_SDA15S0_RELA:
+ pr_err("%s: unsupported relocation type %d.\n",
+ module->name, ELF32_R_TYPE(rel->r_info));
+ pr_err
+ ("Small data section access doesn't work in the kernel space; "
+ "please rebuild the kernel module with gcc option -mcmodel=large.\n");
+ pr_err("section %d reloc %d offset 0x%x size %d\n",
+ relindex, i, rel->r_offset, dstsec->sh_size);
+ break;
+
+ default:
+ pr_err("%s: unsupported relocation type %d.\n",
+ module->name, ELF32_R_TYPE(rel->r_info));
+ pr_err("section %d reloc %d offset 0x%x size %d\n",
+ relindex, i, rel->r_offset, dstsec->sh_size);
+ }
+ }
+ return 0;
+}
+
+int
+apply_relocate(Elf32_Shdr * sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *module)
+{
+ return 0;
+}
+
+int
+module_finalize(const Elf32_Ehdr * hdr, const Elf_Shdr * sechdrs,
+ struct module *module)
+{
+ return 0;
+}
+
+void module_arch_cleanup(struct module *mod)
+{
+}
--
1.7.9.5