[PATCH V7 12/20] csky: ELF and module probe
From: Guo Ren
Date: Fri Oct 05 2018 - 01:45:53 EST
This patch adds ELF definition and module relocate codes.
Signed-off-by: Guo Ren <ren_guo@xxxxxxxxx>
---
arch/csky/abiv1/inc/abi/elf.h | 26 ++++++++++++
arch/csky/abiv2/inc/abi/elf.h | 43 ++++++++++++++++++++
arch/csky/include/asm/elf.h | 85 +++++++++++++++++++++++++++++++++++++++
arch/csky/kernel/module.c | 92 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 246 insertions(+)
create mode 100644 arch/csky/abiv1/inc/abi/elf.h
create mode 100644 arch/csky/abiv2/inc/abi/elf.h
create mode 100644 arch/csky/include/asm/elf.h
create mode 100644 arch/csky/kernel/module.c
diff --git a/arch/csky/abiv1/inc/abi/elf.h b/arch/csky/abiv1/inc/abi/elf.h
new file mode 100644
index 0000000..3058cc0
--- /dev/null
+++ b/arch/csky/abiv1/inc/abi/elf.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ABI_CSKY_ELF_H
+#define __ABI_CSKY_ELF_H
+
+#define ELF_CORE_COPY_REGS(pr_reg, regs) do { \
+ pr_reg[0] = regs->pc; \
+ pr_reg[1] = regs->regs[9]; \
+ pr_reg[2] = regs->usp; \
+ pr_reg[3] = regs->sr; \
+ pr_reg[4] = regs->a0; \
+ pr_reg[5] = regs->a1; \
+ pr_reg[6] = regs->a2; \
+ pr_reg[7] = regs->a3; \
+ pr_reg[8] = regs->regs[0]; \
+ pr_reg[9] = regs->regs[1]; \
+ pr_reg[10] = regs->regs[2]; \
+ pr_reg[11] = regs->regs[3]; \
+ pr_reg[12] = regs->regs[4]; \
+ pr_reg[13] = regs->regs[5]; \
+ pr_reg[14] = regs->regs[6]; \
+ pr_reg[15] = regs->regs[7]; \
+ pr_reg[16] = regs->regs[8]; \
+ pr_reg[17] = regs->lr; \
+} while (0);
+#endif /* __ABI_CSKY_ELF_H */
diff --git a/arch/csky/abiv2/inc/abi/elf.h b/arch/csky/abiv2/inc/abi/elf.h
new file mode 100644
index 0000000..290f49e
--- /dev/null
+++ b/arch/csky/abiv2/inc/abi/elf.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ABI_CSKY_ELF_H
+#define __ABI_CSKY_ELF_H
+
+/* The member sort in array pr_reg[x] is defined by GDB. */
+#define ELF_CORE_COPY_REGS(pr_reg, regs) do { \
+ pr_reg[0] = regs->pc; \
+ pr_reg[1] = regs->a1; \
+ pr_reg[2] = regs->a0; \
+ pr_reg[3] = regs->sr; \
+ pr_reg[4] = regs->a2; \
+ pr_reg[5] = regs->a3; \
+ pr_reg[6] = regs->regs[0]; \
+ pr_reg[7] = regs->regs[1]; \
+ pr_reg[8] = regs->regs[2]; \
+ pr_reg[9] = regs->regs[3]; \
+ pr_reg[10] = regs->regs[4]; \
+ pr_reg[11] = regs->regs[5]; \
+ pr_reg[12] = regs->regs[6]; \
+ pr_reg[13] = regs->regs[7]; \
+ pr_reg[14] = regs->regs[8]; \
+ pr_reg[15] = regs->regs[9]; \
+ pr_reg[16] = regs->usp; \
+ pr_reg[17] = regs->lr; \
+ pr_reg[18] = regs->exregs[0]; \
+ pr_reg[19] = regs->exregs[1]; \
+ pr_reg[20] = regs->exregs[2]; \
+ pr_reg[21] = regs->exregs[3]; \
+ pr_reg[22] = regs->exregs[4]; \
+ pr_reg[23] = regs->exregs[5]; \
+ pr_reg[24] = regs->exregs[6]; \
+ pr_reg[25] = regs->exregs[7]; \
+ pr_reg[26] = regs->exregs[8]; \
+ pr_reg[27] = regs->exregs[9]; \
+ pr_reg[28] = regs->exregs[10]; \
+ pr_reg[29] = regs->exregs[11]; \
+ pr_reg[30] = regs->exregs[12]; \
+ pr_reg[31] = regs->exregs[13]; \
+ pr_reg[32] = regs->exregs[14]; \
+ pr_reg[33] = regs->tls; \
+} while (0);
+#endif /* __ABI_CSKY_ELF_H */
diff --git a/arch/csky/include/asm/elf.h b/arch/csky/include/asm/elf.h
new file mode 100644
index 0000000..773b133
--- /dev/null
+++ b/arch/csky/include/asm/elf.h
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_ELF_H
+#define __ASM_CSKY_ELF_H
+
+#include <asm/ptrace.h>
+#include <abi/regdef.h>
+
+#define ELF_ARCH 252
+
+/* CSKY Relocations */
+#define R_CSKY_NONE 0
+#define R_CSKY_32 1
+#define R_CSKY_PCIMM8BY4 2
+#define R_CSKY_PCIMM11BY2 3
+#define R_CSKY_PCIMM4BY2 4
+#define R_CSKY_PC32 5
+#define R_CSKY_PCRELJSR_IMM11BY2 6
+#define R_CSKY_GNU_VTINHERIT 7
+#define R_CSKY_GNU_VTENTRY 8
+#define R_CSKY_RELATIVE 9
+#define R_CSKY_COPY 10
+#define R_CSKY_GLOB_DAT 11
+#define R_CSKY_JUMP_SLOT 12
+#define R_CSKY_ADDR_HI16 24
+#define R_CSKY_ADDR_LO16 25
+#define R_CSKY_PCRELJSR_IMM26BY2 40
+
+typedef unsigned long elf_greg_t;
+
+typedef struct user_fp elf_fpregset_t;
+
+#define ELF_NGREG (sizeof(struct pt_regs) / sizeof(elf_greg_t))
+
+typedef elf_greg_t elf_gregset_t[ELF_NGREG];
+
+/*
+ * This is used to ensure we don't load something for the wrong architecture.
+ */
+#define elf_check_arch(x) ((x)->e_machine == ELF_ARCH)
+
+/*
+ * These are used to set parameters in the core dumps.
+ */
+#define USE_ELF_CORE_DUMP
+#define ELF_EXEC_PAGESIZE 4096
+#define ELF_CLASS ELFCLASS32
+#define ELF_PLAT_INIT(_r, load_addr) { _r->a0 = 0; }
+
+#ifdef __cskyBE__
+#define ELF_DATA ELFDATA2MSB
+#else
+#define ELF_DATA ELFDATA2LSB
+#endif
+
+/*
+ * This is the location that an ET_DYN program is loaded if exec'ed. Typical
+ * use of this is to invoke "./ld.so someprog" to test out a new version of
+ * the loader. We need to make sure that it is out of the way of the program
+ * that it will "exec", and that there is sufficient room for the brk.
+ */
+#define ELF_ET_DYN_BASE 0x0UL
+#include <abi/elf.h>
+
+/* Similar, but for a thread other than current. */
+struct task_struct;
+extern int dump_task_regs(struct task_struct *tsk, elf_gregset_t *elf_regs);
+#define ELF_CORE_COPY_TASK_REGS(tsk, elf_regs) dump_task_regs(tsk, elf_regs)
+
+#define ELF_HWCAP (0)
+
+/*
+ * This yields a string that ld.so will use to load implementation specific
+ * libraries for optimization. This is more specific in intent than poking
+ * at uname or /proc/cpuinfo.
+ */
+#define ELF_PLATFORM (NULL)
+#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
+struct linux_binprm;
+extern int arch_setup_additional_pages(struct linux_binprm *bprm,
+ int uses_interp);
+#endif /* __ASM_CSKY_ELF_H */
diff --git a/arch/csky/kernel/module.c b/arch/csky/kernel/module.c
new file mode 100644
index 0000000..65abab0
--- /dev/null
+++ b/arch/csky/kernel/module.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <asm/pgtable.h>
+
+#if defined(__CSKYABIV2__)
+#define IS_BSR32(hi16, lo16) (((hi16) & 0xFC00) == 0xE000)
+#define IS_JSRI32(hi16, lo16) ((hi16) == 0xEAE0)
+
+#define CHANGE_JSRI_TO_LRW(addr) do { \
+ *(uint16_t *)(addr) = (*(uint16_t *)(addr) & 0xFF9F) | 0x001a; \
+ *((uint16_t *)(addr) + 1) = *((uint16_t *)(addr) + 1) & 0xFFFF; \
+} while (0)
+
+#define SET_JSR32_R26(addr) do { \
+ *(uint16_t *)(addr) = 0xE8Fa; \
+ *((uint16_t *)(addr) + 1) = 0x0000; \
+} while (0)
+#endif
+
+int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec, struct module *me)
+{
+ unsigned int i;
+ Elf32_Rela *rel = (void *) sechdrs[relsec].sh_addr;
+ Elf32_Sym *sym;
+ uint32_t *location;
+ short *temp;
+#if defined(__CSKYABIV2__)
+ uint16_t *location_tmp;
+#endif
+
+ for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+ /* This is where to make the change */
+ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ + rel[i].r_offset;
+ sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+ + ELF32_R_SYM(rel[i].r_info);
+
+ switch (ELF32_R_TYPE(rel[i].r_info)) {
+ case R_CSKY_32:
+ /* We add the value into the location given */
+ *location = rel[i].r_addend + sym->st_value;
+ break;
+ case R_CSKY_PC32:
+ /* Add the value, subtract its postition */
+ *location = rel[i].r_addend + sym->st_value
+ - (uint32_t)location;
+ break;
+ case R_CSKY_PCRELJSR_IMM11BY2:
+ break;
+ case R_CSKY_PCRELJSR_IMM26BY2:
+#if defined(__CSKYABIV2__)
+ location_tmp = (uint16_t *)location;
+ if (IS_BSR32(*location_tmp, *(location_tmp + 1)))
+ break;
+
+ if (IS_JSRI32(*location_tmp, *(location_tmp + 1))) {
+ /* jsri 0x... --> lrw r26, 0x... */
+ CHANGE_JSRI_TO_LRW(location);
+ /* lsli r0, r0 --> jsr r26 */
+ SET_JSR32_R26(location + 1);
+ }
+#endif
+ break;
+ case R_CSKY_ADDR_HI16:
+ temp = ((short *)location) + 1;
+ *temp = (short)
+ ((rel[i].r_addend + sym->st_value) >> 16);
+ break;
+ case R_CSKY_ADDR_LO16:
+ temp = ((short *)location) + 1;
+ *temp = (short)
+ ((rel[i].r_addend + sym->st_value) & 0xffff);
+ break;
+ default:
+ pr_err("module %s: Unknown relocation: %u\n",
+ me->name, ELF32_R_TYPE(rel[i].r_info));
+ return -ENOEXEC;
+ }
+ }
+ return 0;
+}
--
2.7.4