Hi,
On 5/14/22 16:03, Huacai Chen wrote:
Add ELF-related definition and module relocate codes for basic LoongArch
support.
"module relocation code"
Cc: Jessica Yu <jeyu@xxxxxxxxxx>
Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
---
arch/loongarch/include/asm/cpufeature.h | 24 ++
arch/loongarch/include/asm/elf.h | 299 ++++++++++++++++++
arch/loongarch/include/asm/exec.h | 10 +
arch/loongarch/include/asm/module.h | 80 +++++
arch/loongarch/include/asm/module.lds.h | 7 +
arch/loongarch/include/asm/vermagic.h | 19 ++
arch/loongarch/include/uapi/asm/auxvec.h | 17 ++
arch/loongarch/include/uapi/asm/hwcap.h | 20 ++
arch/loongarch/kernel/elf.c | 30 ++
arch/loongarch/kernel/inst.c | 40 +++
arch/loongarch/kernel/module-sections.c | 121 ++++++++
arch/loongarch/kernel/module.c | 374 +++++++++++++++++++++++
12 files changed, 1041 insertions(+)
create mode 100644 arch/loongarch/include/asm/cpufeature.h
create mode 100644 arch/loongarch/include/asm/elf.h
create mode 100644 arch/loongarch/include/asm/exec.h
create mode 100644 arch/loongarch/include/asm/module.h
create mode 100644 arch/loongarch/include/asm/module.lds.h
create mode 100644 arch/loongarch/include/asm/vermagic.h
create mode 100644 arch/loongarch/include/uapi/asm/auxvec.h
create mode 100644 arch/loongarch/include/uapi/asm/hwcap.h
create mode 100644 arch/loongarch/kernel/elf.c
create mode 100644 arch/loongarch/kernel/inst.c
create mode 100644 arch/loongarch/kernel/module-sections.c
create mode 100644 arch/loongarch/kernel/module.c
diff --git a/arch/loongarch/include/asm/cpufeature.h b/arch/loongarch/include/asm/cpufeature.h
new file mode 100644
index 000000000000..4da22a8e63de
--- /dev/null
+++ b/arch/loongarch/include/asm/cpufeature.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * CPU feature definitions for module loading, used by
+ * module_cpu_feature_match(), see uapi/asm/hwcap.h for LoongArch CPU features.
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#ifndef __ASM_CPUFEATURE_H
+#define __ASM_CPUFEATURE_H
+
+#include <uapi/asm/hwcap.h>
+#include <asm/elf.h>
+
+#define MAX_CPU_FEATURES (8 * sizeof(elf_hwcap))
+
+#define cpu_feature(x) ilog2(HWCAP_ ## x)
+
+static inline bool cpu_have_feature(unsigned int num)
+{
+ return elf_hwcap & (1UL << num);
+}
+
+#endif /* __ASM_CPUFEATURE_H */
diff --git a/arch/loongarch/include/asm/elf.h b/arch/loongarch/include/asm/elf.h
new file mode 100644
index 000000000000..52734d705545
--- /dev/null
+++ b/arch/loongarch/include/asm/elf.h
@@ -0,0 +1,299 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_ELF_H
+#define _ASM_ELF_H
+
+#include <linux/auxvec.h>
+#include <linux/fs.h>
+#include <uapi/linux/elf.h>
+
+#include <asm/current.h>
+#include <asm/vdso.h>
+
+/* ELF header e_flags defines. */
+
+/* The ABI of a file. */
+#define EF_LARCH_ABI_LP32 0x00000001 /* LP32 ABI. */
+#define EF_LARCH_ABI_LP64 0x00000003 /* LP64 ABI */
+#define EF_LARCH_ABI 0x00000003
These 3 constants are unused anywhere else, in addition they're from the
old-world. (New-world definitions can be checked at [1]; and it'll soon
get amended *again*, discussion at [2] in Chinese.)
It seems we could just remove the definitions for now.
[1]:
https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=include/elf/loongarch.h;h=b7aa4ff069c4ce9c60d046274ad9cc74cb2e5d6b;hb=HEAD#l95
[2]: https://github.com/loongson/LoongArch-Documentation/pull/47
+
+/* LoongArch relocation types used by the dynamic linker */
+#define R_LARCH_NONE 0
+#define R_LARCH_32 1
+#define R_LARCH_64 2
+#define R_LARCH_RELATIVE 3
+#define R_LARCH_COPY 4
+#define R_LARCH_JUMP_SLOT 5
+#define R_LARCH_TLS_DTPMOD32 6
+#define R_LARCH_TLS_DTPMOD64 7
+#define R_LARCH_TLS_DTPREL32 8
+#define R_LARCH_TLS_DTPREL64 9
+#define R_LARCH_TLS_TPREL32 10
+#define R_LARCH_TLS_TPREL64 11
+#define R_LARCH_IRELATIVE 12
+#define R_LARCH_MARK_LA 20
+#define R_LARCH_MARK_PCREL 21
+#define R_LARCH_SOP_PUSH_PCREL 22
+#define R_LARCH_SOP_PUSH_ABSOLUTE 23
+#define R_LARCH_SOP_PUSH_DUP 24
+#define R_LARCH_SOP_PUSH_GPREL 25
+#define R_LARCH_SOP_PUSH_TLS_TPREL 26
+#define R_LARCH_SOP_PUSH_TLS_GOT 27
+#define R_LARCH_SOP_PUSH_TLS_GD 28
+#define R_LARCH_SOP_PUSH_PLT_PCREL 29
+#define R_LARCH_SOP_ASSERT 30
+#define R_LARCH_SOP_NOT 31
+#define R_LARCH_SOP_SUB 32
+#define R_LARCH_SOP_SL 33
+#define R_LARCH_SOP_SR 34
+#define R_LARCH_SOP_ADD 35
+#define R_LARCH_SOP_AND 36
+#define R_LARCH_SOP_IF_ELSE 37
+#define R_LARCH_SOP_POP_32_S_10_5 38
+#define R_LARCH_SOP_POP_32_U_10_12 39
+#define R_LARCH_SOP_POP_32_S_10_12 40
+#define R_LARCH_SOP_POP_32_S_10_16 41
+#define R_LARCH_SOP_POP_32_S_10_16_S2 42
+#define R_LARCH_SOP_POP_32_S_5_20 43
+#define R_LARCH_SOP_POP_32_S_0_5_10_16_S2 44
+#define R_LARCH_SOP_POP_32_S_0_10_10_16_S2 45
+#define R_LARCH_SOP_POP_32_U 46
+#define R_LARCH_ADD8 47
+#define R_LARCH_ADD16 48
+#define R_LARCH_ADD24 49
+#define R_LARCH_ADD32 50
+#define R_LARCH_ADD64 51
+#define R_LARCH_SUB8 52
+#define R_LARCH_SUB16 53
+#define R_LARCH_SUB24 54
+#define R_LARCH_SUB32 55
+#define R_LARCH_SUB64 56
+#define R_LARCH_GNU_VTINHERIT 57
+#define R_LARCH_GNU_VTENTRY 58
+
+#ifndef ELF_ARCH
+
+/* ELF register definitions */
+
+/*
+ * General purpose have the following registers:
+ * Register Number
+ * GPRs 32
+ * ORIG_A0 1
+ * ERA 1
+ * BADVADDR 1
+ * CRMD 1
+ * PRMD 1
+ * EUEN 1
+ * ECFG 1
+ * ESTAT 1
+ * Reserved 5
+ */
+#define ELF_NGREG 45
+
+/*
+ * Floating point have the following registers:
+ * Register Number
+ * FPR 32
+ * FCC 1
+ * FCSR 1
+ */
+#define ELF_NFPREG 34
+
+typedef unsigned long elf_greg_t;
+typedef elf_greg_t elf_gregset_t[ELF_NGREG];
+
+typedef double elf_fpreg_t;
+typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG];
+
+void loongarch_dump_regs64(u64 *uregs, const struct pt_regs *regs);
+
+#ifdef CONFIG_32BIT
+/*
+ * This is used to ensure we don't load something for the wrong architecture.
+ */
+#define elf_check_arch elf32_check_arch
+
+/*
+ * These are used to set parameters in the core dumps.
+ */
+#define ELF_CLASS ELFCLASS32
+
+#define ELF_CORE_COPY_REGS(dest, regs) \
+ loongarch_dump_regs32((u32 *)&(dest), (regs));
+
+#endif /* CONFIG_32BIT */
+
+#ifdef CONFIG_64BIT
+/*
+ * This is used to ensure we don't load something for the wrong architecture.
+ */
+#define elf_check_arch elf64_check_arch
+
+/*
+ * These are used to set parameters in the core dumps.
+ */
+#define ELF_CLASS ELFCLASS64
+
+#define ELF_CORE_COPY_REGS(dest, regs) \
+ loongarch_dump_regs64((u64 *)&(dest), (regs));
+
+#endif /* CONFIG_64BIT */
+
+/*
+ * These are used to set parameters in the core dumps.
+ */
+#define ELF_DATA ELFDATA2LSB
+#define ELF_ARCH EM_LOONGARCH
+
+#endif /* !defined(ELF_ARCH) */
+
+#define loongarch_elf_check_machine(x) ((x)->e_machine == EM_LOONGARCH)
+
+#define vmcore_elf32_check_arch loongarch_elf_check_machine
+#define vmcore_elf64_check_arch loongarch_elf_check_machine
+
+/*
+ * Return non-zero if HDR identifies an 32bit ELF binary.
+ */
+#define elf32_check_arch(hdr) \
+({ \
+ int __res = 1; \
+ struct elfhdr *__h = (hdr); \
+ \
+ if (!loongarch_elf_check_machine(__h)) \
+ __res = 0; \
+ if (__h->e_ident[EI_CLASS] != ELFCLASS32) \
+ __res = 0; \
+ \
+ __res; \
+})
+
+/*
+ * Return non-zero if HDR identifies an 64bit ELF binary.
+ */
+#define elf64_check_arch(hdr) \
+({ \
+ int __res = 1; \
+ struct elfhdr *__h = (hdr); \
+ \
+ if (!loongarch_elf_check_machine(__h)) \
+ __res = 0; \
+ if (__h->e_ident[EI_CLASS] != ELFCLASS64) \
+ __res = 0; \
+ \
+ __res; \
+})
+
+#ifdef CONFIG_32BIT
+
+#define SET_PERSONALITY2(ex, state) \
+do { \
+ current->thread.vdso = &vdso_info; \
+ \
+ loongarch_set_personality_fcsr(state); \
+ \
+ if (personality(current->personality) != PER_LINUX) \
+ set_personality(PER_LINUX); \
+} while (0)
+
+#endif /* CONFIG_32BIT */
+
+#ifdef CONFIG_64BIT
+
+#define SET_PERSONALITY2(ex, state) \
+do { \
+ unsigned int p; \
+ \
+ clear_thread_flag(TIF_32BIT_REGS); \
+ clear_thread_flag(TIF_32BIT_ADDR); \
+ \
+ current->thread.vdso = &vdso_info; \
+ loongarch_set_personality_fcsr(state); \
+ \
+ p = personality(current->personality); \
+ if (p != PER_LINUX32 && p != PER_LINUX) \
+ set_personality(PER_LINUX); \
+} while (0)
+
+#endif /* CONFIG_64BIT */
+
+#define CORE_DUMP_USE_REGSET
+#define ELF_EXEC_PAGESIZE PAGE_SIZE
+
+/*
+ * This yields a mask that user programs can use to figure out what
+ * instruction set this cpu supports. This could be done in userspace,
+ * but it's not easy, and we've already done it here.
+ */
+
+#define ELF_HWCAP (elf_hwcap)
+extern unsigned int elf_hwcap;
+#include <asm/hwcap.h>
+
+/*
+ * 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 __elf_platform
+extern const char *__elf_platform;
+
+#define ELF_PLAT_INIT(_r, load_addr) do { \
+ _r->regs[1] = _r->regs[2] = _r->regs[3] = _r->regs[4] = 0; \
+ _r->regs[5] = _r->regs[6] = _r->regs[7] = _r->regs[8] = 0; \
+ _r->regs[9] = _r->regs[10] = _r->regs[11] = _r->regs[12] = 0; \
+ _r->regs[13] = _r->regs[14] = _r->regs[15] = _r->regs[16] = 0; \
+ _r->regs[17] = _r->regs[18] = _r->regs[19] = _r->regs[20] = 0; \
+ _r->regs[21] = _r->regs[22] = _r->regs[23] = _r->regs[24] = 0; \
+ _r->regs[25] = _r->regs[26] = _r->regs[27] = _r->regs[28] = 0; \
+ _r->regs[29] = _r->regs[30] = _r->regs[31] = 0; \
+} while (0)
+
+/*
+ * 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 (TASK_SIZE / 3 * 2)
+
+/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
+#define ARCH_DLINFO \
+do { \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, \
+ (unsigned long)current->mm->context.vdso); \
+} while (0)
+
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
+struct linux_binprm;
+extern int arch_setup_additional_pages(struct linux_binprm *bprm,
+ int uses_interp);
+
+struct arch_elf_state {
+ int fp_abi;
+ int interp_fp_abi;
+};
+
+#define LOONGARCH_ABI_FP_ANY (0)
+
+#define INIT_ARCH_ELF_STATE { \
+ .fp_abi = LOONGARCH_ABI_FP_ANY, \
+ .interp_fp_abi = LOONGARCH_ABI_FP_ANY, \
+}
+
+#define elf_read_implies_exec(ex, exec_stk) (exec_stk == EXSTACK_DEFAULT)
+
+extern int arch_elf_pt_proc(void *ehdr, void *phdr, struct file *elf,
+ bool is_interp, struct arch_elf_state *state);
+
+extern int arch_check_elf(void *ehdr, bool has_interpreter, void *interp_ehdr,
+ struct arch_elf_state *state);
+
+extern void loongarch_set_personality_fcsr(struct arch_elf_state *state);
+
+#endif /* _ASM_ELF_H */
diff --git a/arch/loongarch/include/asm/exec.h b/arch/loongarch/include/asm/exec.h
new file mode 100644
index 000000000000..ba0220812ebb
--- /dev/null
+++ b/arch/loongarch/include/asm/exec.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_EXEC_H
+#define _ASM_EXEC_H
+
+extern unsigned long arch_align_stack(unsigned long sp);
+
+#endif /* _ASM_EXEC_H */
diff --git a/arch/loongarch/include/asm/module.h b/arch/loongarch/include/asm/module.h
new file mode 100644
index 000000000000..5f716a851083
--- /dev/null
+++ b/arch/loongarch/include/asm/module.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_MODULE_H
+#define _ASM_MODULE_H
+
+#include <asm/inst.h>
+#include <asm-generic/module.h>
+
+#define RELA_STACK_DEPTH 16
+
+struct mod_section {
+ Elf_Shdr *shdr;
+ int num_entries;
+ int max_entries;
+};
+
+struct mod_arch_specific {
+ struct mod_section plt;
+ struct mod_section plt_idx;
+};
+
+struct plt_entry {
+ u32 inst_lu12iw;
+ u32 inst_lu32id;
+ u32 inst_lu52id;
+ u32 inst_jirl;
+};
+
+struct plt_idx_entry {
+ unsigned long symbol_addr;
+};
+
+Elf_Addr module_emit_plt_entry(struct module *mod, unsigned long val);
+
+static inline struct plt_entry emit_plt_entry(unsigned long val)
+{
+ u32 lu12iw, lu32id, lu52id, jirl;
+
+ lu12iw = (lu12iw_op << 25 | (((val >> 12) & 0xfffff) << 5) | LOONGARCH_GPR_T1),
And here's that instruction, famously ubiquitous while not belonging to
any of the 9 "basic" formats (hence no helper for emitting it).
We can adopt the loongarch-opcodes [3] scheme and make everything
consistent later. ;-)
[3]: https://github.com/loongson-community/loongarch-opcodes
(Disclaimer: I'm the creator and maintainer of said community scheme,
although that doesn't make the "official" or "ISA manual" scheme more
correct.)
+ lu32id = larch_insn_gen_lu32id(LOONGARCH_GPR_T1, ADDR_IMM(val, LU32ID));
+ lu52id = larch_insn_gen_lu52id(LOONGARCH_GPR_T1, LOONGARCH_GPR_T1, ADDR_IMM(val, LU52ID));
+ jirl = larch_insn_gen_jirl(0, LOONGARCH_GPR_T1, 0, (val & 0xfff));
+
+ return (struct plt_entry) { lu12iw, lu32id, lu52id, jirl };
+}
+
+static inline struct plt_idx_entry emit_plt_idx_entry(unsigned long val)
+{
+ return (struct plt_idx_entry) { val };
+}
+
+static inline int get_plt_idx(unsigned long val, const struct mod_section *sec)
+{
+ int i;
+ struct plt_idx_entry *plt_idx = (struct plt_idx_entry *)sec->shdr->sh_addr;
+
+ for (i = 0; i < sec->num_entries; i++) {
+ if (plt_idx[i].symbol_addr == val)
+ return i;
+ }
+
+ return -1;
+}
+
+static inline struct plt_entry *get_plt_entry(unsigned long val,
+ const struct mod_section *sec_plt,
+ const struct mod_section *sec_plt_idx)
+{
+ int plt_idx = get_plt_idx(val, sec_plt_idx);
+ struct plt_entry *plt = (struct plt_entry *)sec_plt->shdr->sh_addr;
+
+ if (plt_idx < 0)
+ return NULL;
+
+ return plt + plt_idx;
+}
+
+#endif /* _ASM_MODULE_H */
diff --git a/arch/loongarch/include/asm/module.lds.h b/arch/loongarch/include/asm/module.lds.h
new file mode 100644
index 000000000000..31c1c0db11a3
--- /dev/null
+++ b/arch/loongarch/include/asm/module.lds.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2020-2022 Loongson Technology Corporation Limited */
+SECTIONS {
+ . = ALIGN(4);
+ .plt : { BYTE(0) }
+ .plt.idx : { BYTE(0) }
+}
diff --git a/arch/loongarch/include/asm/vermagic.h b/arch/loongarch/include/asm/vermagic.h
new file mode 100644
index 000000000000..8b47ccfe3aad
--- /dev/null
+++ b/arch/loongarch/include/asm/vermagic.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_VERMAGIC_H
+#define _ASM_VERMAGIC_H
+
+#define MODULE_PROC_FAMILY "LOONGARCH "
+
+#ifdef CONFIG_32BIT
+#define MODULE_KERNEL_TYPE "32BIT "
+#elif defined CONFIG_64BIT
+#define MODULE_KERNEL_TYPE "64BIT "
+#endif
+
+#define MODULE_ARCH_VERMAGIC \
+ MODULE_PROC_FAMILY MODULE_KERNEL_TYPE
+
+#endif /* _ASM_VERMAGIC_H */
diff --git a/arch/loongarch/include/uapi/asm/auxvec.h b/arch/loongarch/include/uapi/asm/auxvec.h
new file mode 100644
index 000000000000..922d9e6b5058
--- /dev/null
+++ b/arch/loongarch/include/uapi/asm/auxvec.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Author: Hanlu Li <lihanlu@xxxxxxxxxxx>
+ * Huacai Chen <chenhuacai@xxxxxxxxxxx>
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#ifndef __ASM_AUXVEC_H
+#define __ASM_AUXVEC_H
+
+/* Location of VDSO image. */
+#define AT_SYSINFO_EHDR 33
+
+#define AT_VECTOR_SIZE_ARCH 1 /* entries in ARCH_DLINFO */
+
+#endif /* __ASM_AUXVEC_H */
diff --git a/arch/loongarch/include/uapi/asm/hwcap.h b/arch/loongarch/include/uapi/asm/hwcap.h
new file mode 100644
index 000000000000..8840b72fa8e8
--- /dev/null
+++ b/arch/loongarch/include/uapi/asm/hwcap.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_ASM_HWCAP_H
+#define _UAPI_ASM_HWCAP_H
+
+/* HWCAP flags */
+#define HWCAP_LOONGARCH_CPUCFG (1 << 0)
+#define HWCAP_LOONGARCH_LAM (1 << 1)
+#define HWCAP_LOONGARCH_UAL (1 << 2)
+#define HWCAP_LOONGARCH_FPU (1 << 3)
+#define HWCAP_LOONGARCH_LSX (1 << 4)
+#define HWCAP_LOONGARCH_LASX (1 << 5)
+#define HWCAP_LOONGARCH_CRC32 (1 << 6)
+#define HWCAP_LOONGARCH_COMPLEX (1 << 7)
+#define HWCAP_LOONGARCH_CRYPTO (1 << 8)
+#define HWCAP_LOONGARCH_LVZ (1 << 9)
+#define HWCAP_LOONGARCH_LBT_X86 (1 << 10)
+#define HWCAP_LOONGARCH_LBT_ARM (1 << 11)
+#define HWCAP_LOONGARCH_LBT_MIPS (1 << 12)
+
+#endif /* _UAPI_ASM_HWCAP_H */
diff --git a/arch/loongarch/kernel/elf.c b/arch/loongarch/kernel/elf.c
new file mode 100644
index 000000000000..183e94fc9c69
--- /dev/null
+++ b/arch/loongarch/kernel/elf.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Huacai Chen <chenhuacai@xxxxxxxxxxx>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/binfmts.h>
+#include <linux/elf.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+
+#include <asm/cpu-features.h>
+#include <asm/cpu-info.h>
+
+int arch_elf_pt_proc(void *_ehdr, void *_phdr, struct file *elf,
+ bool is_interp, struct arch_elf_state *state)
+{
+ return 0;
+}
+
+int arch_check_elf(void *_ehdr, bool has_interpreter, void *_interp_ehdr,
+ struct arch_elf_state *state)
+{
+ return 0;
+}
+
+void loongarch_set_personality_fcsr(struct arch_elf_state *state)
+{
+ current->thread.fpu.fcsr = boot_cpu_data.fpu_csr0;
+}
diff --git a/arch/loongarch/kernel/inst.c b/arch/loongarch/kernel/inst.c
new file mode 100644
index 000000000000..b1df0ec34bd1
--- /dev/null
+++ b/arch/loongarch/kernel/inst.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <asm/inst.h>
+
+u32 larch_insn_gen_lu32id(enum loongarch_gpr rd, int imm)
+{
+ union loongarch_instruction insn;
+
+ insn.reg1i20_format.opcode = lu32id_op;
+ insn.reg1i20_format.rd = rd;
+ insn.reg1i20_format.immediate = imm;
+
+ return insn.word;
+}
+
+u32 larch_insn_gen_lu52id(enum loongarch_gpr rd, enum loongarch_gpr rj, int imm)
+{
+ union loongarch_instruction insn;
+
+ insn.reg2i12_format.opcode = lu52id_op;
+ insn.reg2i12_format.rd = rd;
+ insn.reg2i12_format.rj = rj;
+ insn.reg2i12_format.immediate = imm;
+
+ return insn.word;
+}
+
+u32 larch_insn_gen_jirl(enum loongarch_gpr rd, enum loongarch_gpr rj, unsigned long pc, unsigned long dest)
+{
+ union loongarch_instruction insn;
+
+ insn.reg2i16_format.opcode = jirl_op;
+ insn.reg2i16_format.rd = rd;
+ insn.reg2i16_format.rj = rj;
+ insn.reg2i16_format.immediate = (dest - pc) >> 2;
+
+ return insn.word;
+}
diff --git a/arch/loongarch/kernel/module-sections.c b/arch/loongarch/kernel/module-sections.c
new file mode 100644
index 000000000000..6d498288977d
--- /dev/null
+++ b/arch/loongarch/kernel/module-sections.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/elf.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+Elf_Addr module_emit_plt_entry(struct module *mod, unsigned long val)
+{
+ int nr;
+ struct mod_section *plt_sec = &mod->arch.plt;
+ struct mod_section *plt_idx_sec = &mod->arch.plt_idx;
+ struct plt_entry *plt = get_plt_entry(val, plt_sec, plt_idx_sec);
+ struct plt_idx_entry *plt_idx;
+
+ if (plt)
+ return (Elf_Addr)plt;
+
+ nr = plt_sec->num_entries;
+
+ /* There is no duplicate entry, create a new one */
+ plt = (struct plt_entry *)plt_sec->shdr->sh_addr;
+ plt[nr] = emit_plt_entry(val);
+ plt_idx = (struct plt_idx_entry *)plt_idx_sec->shdr->sh_addr;
+ plt_idx[nr] = emit_plt_idx_entry(val);
+
+ plt_sec->num_entries++;
+ plt_idx_sec->num_entries++;
+ BUG_ON(plt_sec->num_entries > plt_sec->max_entries);
+
+ return (Elf_Addr)&plt[nr];
+}
+
+static int is_rela_equal(const Elf_Rela *x, const Elf_Rela *y)
+{
+ return x->r_info == y->r_info && x->r_addend == y->r_addend;
+}
+
+static bool duplicate_rela(const Elf_Rela *rela, int idx)
+{
+ int i;
+
+ for (i = 0; i < idx; i++) {
+ if (is_rela_equal(&rela[i], &rela[idx]))
+ return true;
+ }
+
+ return false;
+}
+
+static void count_max_entries(Elf_Rela *relas, int num, unsigned int *plts)
+{
+ unsigned int i, type;
+
+ for (i = 0; i < num; i++) {
+ type = ELF_R_TYPE(relas[i].r_info);
+ if (type == R_LARCH_SOP_PUSH_PLT_PCREL) {
+ if (!duplicate_rela(relas, i))
+ (*plts)++;
+ }
+ }
+}
+
+int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
+ char *secstrings, struct module *mod)
+{
+ unsigned int i, num_plts = 0;
+
+ /*
+ * Find the empty .plt sections.
+ */
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt"))
+ mod->arch.plt.shdr = sechdrs + i;
+ else if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt.idx"))
+ mod->arch.plt_idx.shdr = sechdrs + i;
+ }
+
+ if (!mod->arch.plt.shdr) {
+ pr_err("%s: module PLT section(s) missing\n", mod->name);
+ return -ENOEXEC;
+ }
+ if (!mod->arch.plt_idx.shdr) {
+ pr_err("%s: module PLT.IDX section(s) missing\n", mod->name);
+ return -ENOEXEC;
+ }
+
+ /* Calculate the maxinum number of entries */
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ int num_rela = sechdrs[i].sh_size / sizeof(Elf_Rela);
+ Elf_Rela *relas = (void *)ehdr + sechdrs[i].sh_offset;
+ Elf_Shdr *dst_sec = sechdrs + sechdrs[i].sh_info;
+
+ if (sechdrs[i].sh_type != SHT_RELA)
+ continue;
+
+ /* ignore relocations that operate on non-exec sections */
+ if (!(dst_sec->sh_flags & SHF_EXECINSTR))
+ continue;
+
+ count_max_entries(relas, num_rela, &num_plts);
+ }
+
+ mod->arch.plt.shdr->sh_type = SHT_NOBITS;
+ mod->arch.plt.shdr->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
+ mod->arch.plt.shdr->sh_addralign = L1_CACHE_BYTES;
+ mod->arch.plt.shdr->sh_size = (num_plts + 1) * sizeof(struct plt_entry);
+ mod->arch.plt.num_entries = 0;
+ mod->arch.plt.max_entries = num_plts;
+
+ mod->arch.plt_idx.shdr->sh_type = SHT_NOBITS;
+ mod->arch.plt_idx.shdr->sh_flags = SHF_ALLOC;
+ mod->arch.plt_idx.shdr->sh_addralign = L1_CACHE_BYTES;
+ mod->arch.plt_idx.shdr->sh_size = (num_plts + 1) * sizeof(struct plt_idx_entry);
+ mod->arch.plt_idx.num_entries = 0;
+ mod->arch.plt_idx.max_entries = num_plts;
+
+ return 0;
+}
diff --git a/arch/loongarch/kernel/module.c b/arch/loongarch/kernel/module.c
new file mode 100644
index 000000000000..f2d3bcd35a39
--- /dev/null
+++ b/arch/loongarch/kernel/module.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Author: Hanlu Li <lihanlu@xxxxxxxxxxx>
+ * Huacai Chen <chenhuacai@xxxxxxxxxxx>
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#define pr_fmt(fmt) "kmod: " fmt
+
+#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>
+
+static inline bool signed_imm_check(long val, unsigned int bit)
+{
+ return -(1L << (bit - 1)) <= val && val < (1L << (bit - 1));
+}
+
+static inline bool unsigned_imm_check(unsigned long val, unsigned int bit)
+{
+ return val < (1UL << bit);
+}
+
+static int rela_stack_push(s64 stack_value, s64 *rela_stack, size_t *rela_stack_top)
+{
+ if (*rela_stack_top >= RELA_STACK_DEPTH)
+ return -ENOEXEC;
+
+ rela_stack[(*rela_stack_top)++] = stack_value;
+ pr_debug("%s stack_value = 0x%llx\n", __func__, stack_value);
+
+ return 0;
+}
+
+static int rela_stack_pop(s64 *stack_value, s64 *rela_stack, size_t *rela_stack_top)
+{
+ if (*rela_stack_top == 0)
+ return -ENOEXEC;
+
+ *stack_value = rela_stack[--(*rela_stack_top)];
+ pr_debug("%s stack_value = 0x%llx\n", __func__, *stack_value);
+
+ return 0;
+}
+
+static int apply_r_larch_none(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ return 0;
+}
+
+static int apply_r_larch_error(struct module *me, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ pr_err("%s: Unsupport relocation type %u, please add its support.\n", me->name, type);
+ return -EINVAL;
+}
+
+static int apply_r_larch_32(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ *location = v;
+ return 0;
+}
+
+static int apply_r_larch_64(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ *(Elf_Addr *)location = v;
+ return 0;
+}
+
+static int apply_r_larch_sop_push_pcrel(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ return rela_stack_push(v - (u64)location, rela_stack, rela_stack_top);
+}
+
+static int apply_r_larch_sop_push_absolute(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ return rela_stack_push(v, rela_stack, rela_stack_top);
+}
+
+static int apply_r_larch_sop_push_dup(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ int err = 0;
+ s64 opr1;
+
+ err = rela_stack_pop(&opr1, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+ err = rela_stack_push(opr1, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+ err = rela_stack_push(opr1, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+static int apply_r_larch_sop_push_plt_pcrel(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ ptrdiff_t offset = (void *)v - (void *)location;
+
+ if (offset >= SZ_128M)
+ v = module_emit_plt_entry(mod, v);
+
+ if (offset < -SZ_128M)
+ v = module_emit_plt_entry(mod, v);
+
+ return apply_r_larch_sop_push_pcrel(mod, location, v, rela_stack, rela_stack_top, type);
+}
+
+static int apply_r_larch_sop(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ int err = 0;
+ s64 opr1, opr2, opr3;
+
+ if (type == R_LARCH_SOP_IF_ELSE) {
+ err = rela_stack_pop(&opr3, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+ }
+
+ err = rela_stack_pop(&opr2, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+ err = rela_stack_pop(&opr1, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+
+ switch (type) {
+ case R_LARCH_SOP_AND:
+ err = rela_stack_push(opr1 & opr2, rela_stack, rela_stack_top);
+ break;
+ case R_LARCH_SOP_ADD:
+ err = rela_stack_push(opr1 + opr2, rela_stack, rela_stack_top);
+ break;
+ case R_LARCH_SOP_SUB:
+ err = rela_stack_push(opr1 - opr2, rela_stack, rela_stack_top);
+ break;
+ case R_LARCH_SOP_SL:
+ err = rela_stack_push(opr1 << opr2, rela_stack, rela_stack_top);
+ break;
+ case R_LARCH_SOP_SR:
+ err = rela_stack_push(opr1 >> opr2, rela_stack, rela_stack_top);
+ break;
+ case R_LARCH_SOP_IF_ELSE:
+ err = rela_stack_push(opr1 ? opr2 : opr3, rela_stack, rela_stack_top);
+ break;
+ default:
+ pr_err("%s: Unsupport relocation type %u handler\n", mod->name, type);
+ return -EINVAL;
+ }
+
+ return err;
+}
+
+static int apply_r_larch_sop_imm_field(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ int err = 0;
+ s64 opr1;
+ union loongarch_instruction *insn = (union loongarch_instruction *)location;
+
+ err = rela_stack_pop(&opr1, rela_stack, rela_stack_top);
+ if (err)
+ return err;
+
+ switch (type) {
+ case R_LARCH_SOP_POP_32_U_10_12:
+ if (!unsigned_imm_check(opr1, 12))
+ goto overflow;
+
+ /* (*(uint32_t *) PC) [21 ... 10] = opr [11 ... 0] */
+ insn->reg2i12_format.immediate = opr1 & 0xfff;
+ return 0;
+ case R_LARCH_SOP_POP_32_S_10_12:
+ if (!signed_imm_check(opr1, 12))
+ goto overflow;
+
+ insn->reg2i12_format.immediate = opr1 & 0xfff;
+ return 0;
+ case R_LARCH_SOP_POP_32_S_10_16:
+ if (!signed_imm_check(opr1, 16))
+ goto overflow;
+
+ insn->reg2i16_format.immediate = opr1 & 0xffff;
+ return 0;
+ case R_LARCH_SOP_POP_32_S_10_16_S2:
+ if (opr1 % 4)
+ goto unaligned;
+
+ if (!signed_imm_check(opr1, 18))
+ goto overflow;
+
+ insn->reg2i16_format.immediate = (opr1 >> 2) & 0xffff;
+ return 0;
+ case R_LARCH_SOP_POP_32_S_5_20:
+ if (!signed_imm_check(opr1, 20))
+ goto overflow;
+
+ insn->reg1i20_format.immediate = (opr1) & 0xfffff;
+ return 0;
+ case R_LARCH_SOP_POP_32_S_0_5_10_16_S2:
+ if (opr1 % 4)
+ goto unaligned;
+
+ if (!signed_imm_check(opr1, 23))
+ goto overflow;
+
+ opr1 >>= 2;
+ insn->reg1i21_format.immediate_l = opr1 & 0xffff;
+ insn->reg1i21_format.immediate_h = (opr1 >> 16) & 0x1f;
+ return 0;
+ case R_LARCH_SOP_POP_32_S_0_10_10_16_S2:
+ if (opr1 % 4)
+ goto unaligned;
+
+ if (!signed_imm_check(opr1, 28))
+ goto overflow;
+
+ opr1 >>= 2;
+ insn->reg0i26_format.immediate_l = opr1 & 0xffff;
+ insn->reg0i26_format.immediate_h = (opr1 >> 16) & 0x3ff;
+ return 0;
+ case R_LARCH_SOP_POP_32_U:
+ if (!unsigned_imm_check(opr1, 32))
+ goto overflow;
+
+ /* (*(uint32_t *) PC) = opr */
+ *location = (u32)opr1;
+ return 0;
+ default:
+ pr_err("%s: Unsupport relocation type %u handler\n", mod->name, type);
"%s: Unsupported relocation type %u" would be enough.
+ return -EINVAL;
+ }
+
+overflow:
+ pr_err("module %s: opr1 = 0x%llx overflow! dangerous %s (%u) relocation\n",
+ mod->name, opr1, __func__, type);
+ return -ENOEXEC;
+
+unaligned:
+ pr_err("module %s: opr1 = 0x%llx unaligned! dangerous %s (%u) relocation\n",
+ mod->name, opr1, __func__, type);
+ return -ENOEXEC;
+}
+
+static int apply_r_larch_add_sub(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type)
+{
+ switch (type) {
+ case R_LARCH_ADD32:
+ *(s32 *)location += v;
+ return 0;
+ case R_LARCH_ADD64:
+ *(s64 *)location += v;
+ return 0;
+ case R_LARCH_SUB32:
+ *(s32 *)location -= v;
+ return 0;
+ case R_LARCH_SUB64:
+ *(s64 *)location -= v;
+ return 0;
+ default:
+ pr_err("%s: Unsupport relocation type %u handler\n", mod->name, type);
+ return -EINVAL;
+ }
+}
+
+/*
+ * reloc_handlers_rela() - Apply a particular relocation to a module
+ * @mod: the module to apply the reloc to
+ * @location: the address at which the reloc is to be applied
+ * @v: the value of the reloc, with addend for RELA-style
+ * @rela_stack: the stack used for store relocation info, LOCAL to THIS module
+ * @rela_stac_top: where the stack operation(pop/push) applies to
+ *
+ * Return: 0 upon success, else -ERRNO
+ */
+typedef int (*reloc_rela_handler)(struct module *mod, u32 *location, Elf_Addr v,
+ s64 *rela_stack, size_t *rela_stack_top, unsigned int type);
+
+/* The handlers for known reloc types */
+static reloc_rela_handler reloc_rela_handlers[] = {
+ [R_LARCH_NONE ... R_LARCH_SUB64] = apply_r_larch_error,
+
+ [R_LARCH_NONE] = apply_r_larch_none,
+ [R_LARCH_32] = apply_r_larch_32,
+ [R_LARCH_64] = apply_r_larch_64,
+ [R_LARCH_MARK_LA] = apply_r_larch_none,
+ [R_LARCH_MARK_PCREL] = apply_r_larch_none,
+ [R_LARCH_SOP_PUSH_PCREL] = apply_r_larch_sop_push_pcrel,
+ [R_LARCH_SOP_PUSH_ABSOLUTE] = apply_r_larch_sop_push_absolute,
+ [R_LARCH_SOP_PUSH_DUP] = apply_r_larch_sop_push_dup,
+ [R_LARCH_SOP_PUSH_PLT_PCREL] = apply_r_larch_sop_push_plt_pcrel,
+ [R_LARCH_SOP_SUB ... R_LARCH_SOP_IF_ELSE] = apply_r_larch_sop,
+ [R_LARCH_SOP_POP_32_S_10_5 ... R_LARCH_SOP_POP_32_U] = apply_r_larch_sop_imm_field,
+ [R_LARCH_ADD32 ... R_LARCH_SUB64] = apply_r_larch_add_sub,
+};
+
+int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *mod)
+{
+ int i, err;
+ unsigned int type;
+ s64 rela_stack[RELA_STACK_DEPTH];
+ size_t rela_stack_top = 0;
+ reloc_rela_handler handler;
+ void *location;
+ Elf_Addr v;
+ Elf_Sym *sym;
+ Elf_Rela *rel = (void *) sechdrs[relsec].sh_addr;
+
+ pr_debug("%s: Applying relocate section %u to %u\n", __func__, relsec,
+ sechdrs[relsec].sh_info);
+
+ rela_stack_top = 0;
+ 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;
+ /* This is the symbol it is referring to */
+ sym = (Elf_Sym *)sechdrs[symindex].sh_addr + ELF_R_SYM(rel[i].r_info);
+ if (IS_ERR_VALUE(sym->st_value)) {
+ /* Ignore unresolved weak symbol */
+ if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
+ continue;
+ pr_warn("%s: Unknown symbol %s\n", mod->name, strtab + sym->st_name);
+ return -ENOENT;
+ }
+
+ type = ELF_R_TYPE(rel[i].r_info);
+
+ if (type < ARRAY_SIZE(reloc_rela_handlers))
+ handler = reloc_rela_handlers[type];
+ else
+ handler = NULL;
+
+ if (!handler) {
+ pr_err("%s: Unknown relocation type %u\n", mod->name, type);
+ return -EINVAL;
+ }
+
+ pr_debug("type %d st_value %llx r_addend %llx loc %llx\n",
+ (int)ELF_R_TYPE(rel[i].r_info),
+ sym->st_value, rel[i].r_addend, (u64)location);
+
+ v = sym->st_value + rel[i].r_addend;
+ err = handler(mod, location, v, rela_stack, &rela_stack_top, type);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+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));
+}
Overall good; with the comments and nits addressed,
Reviewed-by: WANG Xuerui <git@xxxxxxxxxx>
