diff options
| -rw-r--r-- | arch/mips/Kbuild | 1 | ||||
| -rw-r--r-- | arch/mips/include/asm/abi.h | 5 | ||||
| -rw-r--r-- | arch/mips/include/asm/elf.h | 7 | ||||
| -rw-r--r-- | arch/mips/include/asm/processor.h | 8 | ||||
| -rw-r--r-- | arch/mips/include/asm/vdso.h | 73 | ||||
| -rw-r--r-- | arch/mips/include/uapi/asm/Kbuild | 2 | ||||
| -rw-r--r-- | arch/mips/include/uapi/asm/auxvec.h | 17 | ||||
| -rw-r--r-- | arch/mips/kernel/signal.c | 12 | ||||
| -rw-r--r-- | arch/mips/kernel/signal32.c | 7 | ||||
| -rw-r--r-- | arch/mips/kernel/signal_n32.c | 5 | ||||
| -rw-r--r-- | arch/mips/kernel/vdso.c | 160 | ||||
| -rw-r--r-- | arch/mips/vdso/.gitignore | 4 | ||||
| -rw-r--r-- | arch/mips/vdso/Makefile | 160 | ||||
| -rw-r--r-- | arch/mips/vdso/elf.S | 68 | ||||
| -rw-r--r-- | arch/mips/vdso/genvdso.c | 293 | ||||
| -rw-r--r-- | arch/mips/vdso/genvdso.h | 187 | ||||
| -rw-r--r-- | arch/mips/vdso/sigreturn.S | 49 | ||||
| -rw-r--r-- | arch/mips/vdso/vdso.h | 80 | ||||
| -rw-r--r-- | arch/mips/vdso/vdso.lds.S | 100 |
19 files changed, 1114 insertions, 124 deletions
diff --git a/arch/mips/Kbuild b/arch/mips/Kbuild index dd295335891a..5c3f688a5232 100644 --- a/arch/mips/Kbuild +++ b/arch/mips/Kbuild @@ -17,6 +17,7 @@ obj- := $(platform-) obj-y += kernel/ obj-y += mm/ obj-y += net/ +obj-y += vdso/ ifdef CONFIG_KVM obj-y += kvm/ diff --git a/arch/mips/include/asm/abi.h b/arch/mips/include/asm/abi.h index 37f84078e78a..940760844e2f 100644 --- a/arch/mips/include/asm/abi.h +++ b/arch/mips/include/asm/abi.h @@ -11,19 +11,20 @@ #include <asm/signal.h> #include <asm/siginfo.h> +#include <asm/vdso.h> struct mips_abi { int (* const setup_frame)(void *sig_return, struct ksignal *ksig, struct pt_regs *regs, sigset_t *set); - const unsigned long signal_return_offset; int (* const setup_rt_frame)(void *sig_return, struct ksignal *ksig, struct pt_regs *regs, sigset_t *set); - const unsigned long rt_signal_return_offset; const unsigned long restart; unsigned off_sc_fpregs; unsigned off_sc_fpc_csr; unsigned off_sc_used_math; + + struct mips_vdso_image *vdso; }; #endif /* _ASM_ABI_H */ diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h index 53b26933b12c..b01a6ff468e0 100644 --- a/arch/mips/include/asm/elf.h +++ b/arch/mips/include/asm/elf.h @@ -8,6 +8,7 @@ #ifndef _ASM_ELF_H #define _ASM_ELF_H +#include <linux/auxvec.h> #include <linux/fs.h> #include <uapi/linux/elf.h> @@ -419,6 +420,12 @@ extern const char *__elf_platform; #define ELF_ET_DYN_BASE (TASK_SIZE / 3 * 2) #endif +#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, diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h index 59ee6dcf6eed..3f832c3dd8f5 100644 --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -36,12 +36,6 @@ extern unsigned int vced_count, vcei_count; */ #define HAVE_ARCH_PICK_MMAP_LAYOUT 1 -/* - * A special page (the vdso) is mapped into all processes at the very - * top of the virtual memory space. - */ -#define SPECIAL_PAGES_SIZE PAGE_SIZE - #ifdef CONFIG_32BIT #ifdef CONFIG_KVM_GUEST /* User space process size is limited to 1GB in KVM Guest Mode */ @@ -80,7 +74,7 @@ extern unsigned int vced_count, vcei_count; #endif -#define STACK_TOP ((TASK_SIZE & PAGE_MASK) - SPECIAL_PAGES_SIZE) +#define STACK_TOP (TASK_SIZE & PAGE_MASK) /* * This decides where the kernel will search for a free chunk of vm diff --git a/arch/mips/include/asm/vdso.h b/arch/mips/include/asm/vdso.h index cca56aa40ff4..db2d45be8f2e 100644 --- a/arch/mips/include/asm/vdso.h +++ b/arch/mips/include/asm/vdso.h @@ -1,29 +1,70 @@ /* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> * - * Copyright (C) 2009 Cavium Networks + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. */ #ifndef __ASM_VDSO_H #define __ASM_VDSO_H -#include <linux/types.h> +#include <linux/mm_types.h> +/** + * struct mips_vdso_image - Details of a VDSO image. + * @data: Pointer to VDSO image data (page-aligned). + * @size: Size of the VDSO image data (page-aligned). + * @off_sigreturn: Offset of the sigreturn() trampoline. + * @off_rt_sigreturn: Offset of the rt_sigreturn() trampoline. + * @mapping: Special mapping structure. + * + * This structure contains details of a VDSO image, including the image data + * and offsets of certain symbols required by the kernel. It is generated as + * part of the VDSO build process, aside from the mapping page array, which is + * populated at runtime. + */ +struct mips_vdso_image { + void *data; + unsigned long size; -#ifdef CONFIG_32BIT -struct mips_vdso { - u32 signal_trampoline[2]; - u32 rt_signal_trampoline[2]; + unsigned long off_sigreturn; + unsigned long off_rt_sigreturn; + + struct vm_special_mapping mapping; }; -#else /* !CONFIG_32BIT */ -struct mips_vdso { - u32 o32_signal_trampoline[2]; - u32 o32_rt_signal_trampoline[2]; - u32 rt_signal_trampoline[2]; - u32 n32_rt_signal_trampoline[2]; + +/* + * The following structures are auto-generated as part of the build for each + * ABI by genvdso, see arch/mips/vdso/Makefile. + */ + +extern struct mips_vdso_image vdso_image; + +#ifdef CONFIG_MIPS32_O32 +extern struct mips_vdso_image vdso_image_o32; +#endif + +#ifdef CONFIG_MIPS32_N32 +extern struct mips_vdso_image vdso_image_n32; +#endif + +/** + * union mips_vdso_data - Data provided by the kernel for the VDSO. + * + * This structure contains data needed by functions within the VDSO. It is + * populated by the kernel and mapped read-only into user memory. + * + * Note: Care should be taken when modifying as the layout must remain the same + * for both 64- and 32-bit (for 32-bit userland on 64-bit kernel). + */ +union mips_vdso_data { + struct { + }; + + u8 page[PAGE_SIZE]; }; -#endif /* CONFIG_32BIT */ #endif /* __ASM_VDSO_H */ diff --git a/arch/mips/include/uapi/asm/Kbuild b/arch/mips/include/uapi/asm/Kbuild index 96fe7395ed8d..f2cf41461146 100644 --- a/arch/mips/include/uapi/asm/Kbuild +++ b/arch/mips/include/uapi/asm/Kbuild @@ -1,9 +1,9 @@ # UAPI Header export list include include/uapi/asm-generic/Kbuild.asm -generic-y += auxvec.h generic-y += ipcbuf.h +header-y += auxvec.h header-y += bitfield.h header-y += bitsperlong.h header-y += break.h diff --git a/arch/mips/include/uapi/asm/auxvec.h b/arch/mips/include/uapi/asm/auxvec.h new file mode 100644 index 000000000000..c9c7195272c4 --- /dev/null +++ b/arch/mips/include/uapi/asm/auxvec.h @@ -0,0 +1,17 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#ifndef __ASM_AUXVEC_H +#define __ASM_AUXVEC_H + +/* Location of VDSO image. */ +#define AT_SYSINFO_EHDR 33 + +#endif /* __ASM_AUXVEC_H */ diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index 2fec67bfc457..bf792e2839a6 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -36,7 +36,6 @@ #include <asm/ucontext.h> #include <asm/cpu-features.h> #include <asm/war.h> -#include <asm/vdso.h> #include <asm/dsp.h> #include <asm/inst.h> #include <asm/msa.h> @@ -752,16 +751,15 @@ static int setup_rt_frame(void *sig_return, struct ksignal *ksig, struct mips_abi mips_abi = { #ifdef CONFIG_TRAD_SIGNALS .setup_frame = setup_frame, - .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline), #endif .setup_rt_frame = setup_rt_frame, - .rt_signal_return_offset = - offsetof(struct mips_vdso, rt_signal_trampoline), .restart = __NR_restart_syscall, .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), .off_sc_used_math = offsetof(struct sigcontext, sc_used_math), + + .vdso = &vdso_image, }; static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) @@ -801,11 +799,11 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) } if (sig_uses_siginfo(&ksig->ka)) - ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset, + ret = abi->setup_rt_frame(vdso + abi->vdso->off_rt_sigreturn, ksig, regs, oldset); else - ret = abi->setup_frame(vdso + abi->signal_return_offset, ksig, - regs, oldset); + ret = abi->setup_frame(vdso + abi->vdso->off_sigreturn, + ksig, regs, oldset); signal_setup_done(ret, ksig, 0); } diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c index f7e89524e316..4909639aa35b 100644 --- a/arch/mips/kernel/signal32.c +++ b/arch/mips/kernel/signal32.c @@ -31,7 +31,6 @@ #include <asm/ucontext.h> #include <asm/fpu.h> #include <asm/war.h> -#include <asm/vdso.h> #include <asm/dsp.h> #include "signal-common.h" @@ -406,14 +405,12 @@ static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig, */ struct mips_abi mips_abi_32 = { .setup_frame = setup_frame_32, - .signal_return_offset = - offsetof(struct mips_vdso, o32_signal_trampoline), .setup_rt_frame = setup_rt_frame_32, - .rt_signal_return_offset = - offsetof(struct mips_vdso, o32_rt_signal_trampoline), .restart = __NR_O32_restart_syscall, .off_sc_fpregs = offsetof(struct sigcontext32, sc_fpregs), .off_sc_fpc_csr = offsetof(struct sigcontext32, sc_fpc_csr), .off_sc_used_math = offsetof(struct sigcontext32, sc_used_math), + + .vdso = &vdso_image_o32, }; diff --git a/arch/mips/kernel/signal_n32.c b/arch/mips/kernel/signal_n32.c index 0d017fdcaf07..a7bc38430500 100644 --- a/arch/mips/kernel/signal_n32.c +++ b/arch/mips/kernel/signal_n32.c @@ -38,7 +38,6 @@ #include <asm/fpu.h> #include <asm/cpu-features.h> #include <asm/war.h> -#include <asm/vdso.h> #include "signal-common.h" @@ -151,11 +150,11 @@ static int setup_rt_frame_n32(void *sig_return, struct ksignal *ksig, struct mips_abi mips_abi_n32 = { .setup_rt_frame = setup_rt_frame_n32, - .rt_signal_return_offset = - offsetof(struct mips_vdso, n32_rt_signal_trampoline), .restart = __NR_N32_restart_syscall, .off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), .off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), .off_sc_used_math = offsetof(struct sigcontext, sc_used_math), + + .vdso = &vdso_image_n32, }; diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c index ed2a278722a9..56cc3c4377fb 100644 --- a/arch/mips/kernel/vdso.c +++ b/arch/mips/kernel/vdso.c @@ -1,122 +1,116 @@ /* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> * - * Copyright (C) 2009, 2010 Cavium Networks, Inc. + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. */ - -#include <linux/kernel.h> -#include <linux/err.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/init.h> #include <linux/binfmts.h> #include <linux/elf.h> -#include <linux/vmalloc.h> -#include <linux/unistd.h> -#include <linux/random.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <asm/abi.h> #include <asm/vdso.h> -#include <asm/uasm.h> -#include <asm/processor.h> + +/* Kernel-provided data used by the VDSO. */ +static union mips_vdso_data vdso_data __page_aligned_data; /* - * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... + * Mapping for the VDSO data pages. The real pages are mapped manually, as + * what we map and where within the area they are mapped is determined at + * runtime. */ -#define __NR_O32_sigreturn 4119 -#define __NR_O32_rt_sigreturn 4193 -#define __NR_N32_rt_sigreturn 6211 +static struct page *no_pages[] = { NULL }; +static struct vm_special_mapping vdso_vvar_mapping = { + .name = "[vvar]", + .pages = no_pages, +}; -static struct page *vdso_page; - -static void __init install_trampoline(u32 *tramp, unsigned int sigreturn) +static void __init init_vdso_image(struct mips_vdso_image *image) { - uasm_i_addiu(&tramp, 2, 0, sigreturn); /* li v0, sigreturn */ - uasm_i_syscall(&tramp, 0); + unsigned long num_pages, i; + + BUG_ON(!PAGE_ALIGNED(image->data)); + BUG_ON(!PAGE_ALIGNED(image->size)); + + num_pages = image->size / PAGE_SIZE; + + for (i = 0; i < num_pages; i++) { + image->mapping.pages[i] = + virt_to_page(image->data + (i * PAGE_SIZE)); + } } static int __init init_vdso(void) { - struct mips_vdso *vdso; - - vdso_page = alloc_page(GFP_KERNEL); - if (!vdso_page) - panic("Cannot allocate vdso"); - - vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL); - if (!vdso) - panic("Cannot map vdso"); - clear_page(vdso); - - install_trampoline(vdso->rt_signal_trampoline, __NR_rt_sigreturn); -#ifdef CONFIG_32BIT - install_trampoline(vdso->signal_trampoline, __NR_sigreturn); -#else - install_trampoline(vdso->n32_rt_signal_trampoline, - __NR_N32_rt_sigreturn); - install_trampoline(vdso->o32_signal_trampoline, __NR_O32_sigreturn); - install_trampoline(vdso->o32_rt_signal_trampoline, - __NR_O32_rt_sigreturn); + init_vdso_image(&vdso_image); + +#ifdef CONFIG_MIPS32_O32 + init_vdso_image(&vdso_image_o32); #endif - vunmap(vdso); +#ifdef CONFIG_MIPS32_N32 + init_vdso_image(&vdso_image_n32); +#endif return 0; } subsys_initcall(init_vdso); -static unsigned long vdso_addr(unsigned long start) -{ - unsigned long offset = 0UL; - - if (current->flags & PF_RANDOMIZE) { - offset = get_random_int(); - offset <<= PAGE_SHIFT; - if (TASK_IS_32BIT_ADDR) - offset &= 0xfffffful; - else - offset &= 0xffffffful; - } - - return STACK_TOP + offset; -} - int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) { - int ret; - unsigned long addr; + struct mips_vdso_image *image = current->thread.abi->vdso; struct mm_struct *mm = current->mm; + unsigned long base, vdso_addr; + struct vm_area_struct *vma; + int ret; down_write(&mm->mmap_sem); - addr = vdso_addr(mm->start_stack); - - addr = get_unmapped_area(NULL, addr, PAGE_SIZE, 0, 0); - if (IS_ERR_VALUE(addr)) { - ret = addr; - goto up_fail; + base = get_unmapped_area(NULL, 0, PAGE_SIZE + image->size, 0, 0); + if (IS_ERR_VALUE(base)) { + ret = base; + goto out; } - ret = install_special_mapping(mm, addr, PAGE_SIZE, - VM_READ|VM_EXEC| - VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, - &vdso_page); + vdso_addr = base + PAGE_SIZE; + + vma = _install_special_mapping(mm, base, PAGE_SIZE, + VM_READ | VM_MAYREAD, + &vdso_vvar_mapping); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto out; + } + /* Map data page. */ + ret = remap_pfn_range(vma, base, + virt_to_phys(&vdso_data) >> PAGE_SHIFT, + PAGE_SIZE, PAGE_READONLY); if (ret) - goto up_fail; + goto out; + + /* Map VDSO image. */ + vma = _install_special_mapping(mm, vdso_addr, image->size, + VM_READ | VM_EXEC | + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, + &image->mapping); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto out; + } - mm->context.vdso = (void *)addr; + mm->context.vdso = (void *)vdso_addr; + ret = 0; -up_fail: +out: up_write(&mm->mmap_sem); return ret; } - -const char *arch_vma_name(struct vm_area_struct *vma) -{ - if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) - return "[vdso]"; - return NULL; -} diff --git a/arch/mips/vdso/.gitignore b/arch/mips/vdso/.gitignore new file mode 100644 index 000000000000..5286a7d73d79 --- /dev/null +++ b/arch/mips/vdso/.gitignore @@ -0,0 +1,4 @@ +*.so* +vdso-*image.c +genvdso +vdso*.lds diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile new file mode 100644 index 000000000000..ef5f348f386a --- /dev/null +++ b/arch/mips/vdso/Makefile @@ -0,0 +1,160 @@ +# Objects to go into the VDSO. +obj-vdso-y := elf.o gettimeofday.o sigreturn.o + +# Common compiler flags between ABIs. +ccflags-vdso := \ + $(filter -I%,$(KBUILD_CFLAGS)) \ + $(filter -E%,$(KBUILD_CFLAGS)) \ + $(filter -march=%,$(KBUILD_CFLAGS)) +cflags-vdso := $(ccflags-vdso) \ + $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ + -O2 -g -fPIC -fno-common -fno-builtin -G 0 -DDISABLE_BRANCH_PROFILING \ + $(call cc-option, -fno-stack-protector) +aflags-vdso := $(ccflags-vdso) \ + $(filter -I%,$(KBUILD_CFLAGS)) \ + $(filter -E%,$(KBUILD_CFLAGS)) \ + -D__ASSEMBLY__ -Wa,-gdwarf-2 + +# +# For the pre-R6 code in arch/mips/vdso/vdso.h for locating +# the base address of VDSO, the linker will emit a R_MIPS_PC32 +# relocation in binutils > 2.25 but it will fail with older versions +# because that relocation is not supported for that symbol. As a result +# of which we are forced to disable the VDSO symbols when building +# with < 2.25 binutils on pre-R6 kernels. For more references on why we +# can't use other methods to get the base address of VDSO please refer to +# the comments on that file. +# +ifndef CONFIG_CPU_MIPSR6 + ifeq ($(call ld-ifversion, -gt, 22400000, y),) + $(warning MIPS VDSO requires binutils > 2.24) + obj-vdso-y := $(filter-out gettimeofday.o, $(obj-vdso-y)) + ccflags-vdso += -DDISABLE_MIPS_VDSO + endif +endif + +# VDSO linker flags. +VDSO_LDFLAGS := \ + -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1 \ + -nostdlib -shared \ + $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \ + $(call cc-ldoption, -Wl$(comma)--build-id) + +GCOV_PROFILE := n + +# +# Shared build commands. +# + +quiet_cmd_vdsold = VDSO $@ + cmd_vdsold = $(CC) $(c_flags) $(VDSO_LDFLAGS) \ + -Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@ + +hostprogs-y := genvdso + +quiet_cmd_genvdso = GENVDSO $@ +define cmd_genvdso + cp $< $(<:%.dbg=%) && \ + $(OBJCOPY) -S $< $(<:%.dbg=%) && \ + $(obj)/genvdso $< $(<:%.dbg=%) $@ $(VDSO_NAME) +endef + +# +# Build native VDSO. +# + +native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS)) + +targets += $(obj-vdso-y) +targets += vdso.lds vdso.so.dbg vdso.so vdso-image.c + +obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o) + +$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi) +$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi) + +$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(native-abi) + +$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE + $(call if_changed,vdsold) + +$(obj)/vdso-image.c: $(obj)/vdso.so.dbg $(obj)/genvdso FORCE + $(call if_changed,genvdso) + +obj-y += vdso-image.o + +# +# Build O32 VDSO. +# + +# Define these outside the ifdef to ensure they are picked up by clean. +targets += $(obj-vdso-y:%.o=%-o32.o) +targets += vdso-o32.lds vdso-o32.so.dbg vdso-o32.so vdso-o32-image.c + +ifdef CONFIG_MIPS32_O32 + +obj-vdso-o32 := $(obj-vdso-y:%.o=$(obj)/%-o32.o) + +$(obj-vdso-o32): KBUILD_CFLAGS := $(cflags-vdso) -mabi=32 +$(obj-vdso-o32): KBUILD_AFLAGS := $(aflags-vdso) -mabi=32 + +$(obj)/%-o32.o: $(src)/%.S FORCE + $(call if_changed_dep,as_o_S) + +$(obj)/%-o32.o: $(src)/%.c FORCE + $(call cmd,force_checksrc) + $(call if_changed_rule,cc_o_c) + +$(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := -mabi=32 +$(obj)/vdso-o32.lds: $(src)/vdso.lds.S FORCE + $(call if_changed_dep,cpp_lds_S) + +$(obj)/vdso-o32.so.dbg: $(obj)/vdso-o32.lds $(obj-vdso-o32) FORCE + $(call if_changed,vdsold) + +$(obj)/vdso-o32-image.c: VDSO_NAME := o32 +$(obj)/vdso-o32-image.c: $(obj)/vdso-o32.so.dbg $(obj)/genvdso FORCE + $(call if_changed,genvdso) + +obj-y += vdso-o32-image.o + +endif + +# +# Build N32 VDSO. +# + +targets += $(obj-vdso-y:%.o=%-n32.o) +targets += vdso-n32.lds vdso-n32.so.dbg vdso-n32.so vdso-n32-image.c + +ifdef CONFIG_MIPS32_N32 + +obj-vdso-n32 := $(obj-vdso-y:%.o=$(obj)/%-n32.o) + +$(obj-vdso-n32): KBUILD_CFLAGS := $(cflags-vdso) -mabi=n32 +$(obj-vdso-n32): KBUILD_AFLAGS := $(aflags-vdso) -mabi=n32 + +$(obj)/%-n32.o: $(src)/%.S FORCE + $(call if_changed_dep,as_o_S) + +$(obj)/%-n32.o: $(src)/%.c FORCE + $(call cmd,force_checksrc) + $(call if_changed_rule,cc_o_c) + +$(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := -mabi=n32 +$(obj)/vdso-n32.lds: $(src)/vdso.lds.S FORCE + $(call if_changed_dep,cpp_lds_S) + +$(obj)/vdso-n32.so.dbg: $(obj)/vdso-n32.lds $(obj-vdso-n32) FORCE + $(call if_changed,vdsold) + +$(obj)/vdso-n32-image.c: VDSO_NAME := n32 +$(obj)/vdso-n32-image.c: $(obj)/vdso-n32.so.dbg $(obj)/genvdso FORCE + $(call if_changed,genvdso) + +obj-y += vdso-n32-image.o + +endif + +# FIXME: Need install rule for debug. +# Needs to deal with dependency for generation of dbg by cmd_genvdso... diff --git a/arch/mips/vdso/elf.S b/arch/mips/vdso/elf.S new file mode 100644 index 000000000000..be37bbb1f061 --- /dev/null +++ b/arch/mips/vdso/elf.S @@ -0,0 +1,68 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include "vdso.h" + +#include <linux/elfnote.h> +#include <linux/version.h> + +ELFNOTE_START(Linux, 0, "a") + .long LINUX_VERSION_CODE +ELFNOTE_END + +/* + * The .MIPS.abiflags section must be defined with the FP ABI flags set + * to 'any' to be able to link with both old and new libraries. + * Newer toolchains are capable of automatically generating this, but we want + * to work with older toolchains as well. Therefore, we define the contents of + * this section here (under different names), and then genvdso will patch + * it to have the correct name and type. + * + * We base the .MIPS.abiflags section on preprocessor definitions rather than + * CONFIG_* because we need to match the particular ABI we are building the + * VDSO for. + * + * See https://dmz-portal.mips.com/wiki/MIPS_O32_ABI_-_FR0_and_FR1_Interlinking + * for the .MIPS.abiflags section description. + */ + + .section .mips_abiflags, "a" + .align 3 +__mips_abiflags: + .hword 0 /* version */ + .byte __mips /* isa_level */ + + /* isa_rev */ +#ifdef __mips_isa_rev + .byte __mips_isa_rev +#else + .byte 0 +#endif + + /* gpr_size */ +#ifdef __mips64 + .byte 2 /* AFL_REG_64 */ +#else + .byte 1 /* AFL_REG_32 */ +#endif + + /* cpr1_size */ +#if (defined(__mips_isa_rev) && __mips_isa_rev >= 6) || defined(__mips64) + .byte 2 /* AFL_REG_64 */ +#else + .byte 1 /* AFL_REG_32 */ +#endif + + .byte 0 /* cpr2_size (AFL_REG_NONE) */ + .byte 0 /* fp_abi (Val_GNU_MIPS_ABI_FP_ANY) */ + .word 0 /* isa_ext */ + .word 0 /* ases */ + .word 0 /* flags1 */ + .word 0 /* flags2 */ diff --git a/arch/mips/vdso/genvdso.c b/arch/mips/vdso/genvdso.c new file mode 100644 index 000000000000..530a36f465ce --- /dev/null +++ b/arch/mips/vdso/genvdso.c @@ -0,0 +1,293 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +/* + * This tool is used to generate the real VDSO images from the raw image. It + * first patches up the MIPS ABI flags and GNU attributes sections defined in + * elf.S to have the correct name and type. It then generates a C source file + * to be compiled into the kernel containing the VDSO image data and a + * mips_vdso_image struct for it, including symbol offsets extracted from the + * image. + * + * We need to be passed both a stripped and unstripped VDSO image. The stripped + * image is compiled into the kernel, but we must also patch up the unstripped + * image's ABI flags sections so that it can be installed and used for + * debugging. + */ + +#include <sys/mman.h> +#include <sys/stat.h> +#include <sys/types.h> + +#include <byteswap.h> +#include <elf.h> +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <stdarg.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +/* Define these in case the system elf.h is not new enough to have them. */ +#ifndef SHT_GNU_ATTRIBUTES +# define SHT_GNU_ATTRIBUTES 0x6ffffff5 +#endif +#ifndef SHT_MIPS_ABIFLAGS +# define SHT_MIPS_ABIFLAGS 0x7000002a +#endif + +enum { + ABI_O32 = (1 << 0), + ABI_N32 = (1 << 1), + ABI_N64 = (1 << 2), + + ABI_ALL = ABI_O32 | ABI_N32 | ABI_N64, +}; + +/* Symbols the kernel requires offsets for. */ +static struct { + const char *name; + const char *offset_name; + unsigned int abis; +} vdso_symbols[] = { + { "__vdso_sigreturn", "off_sigreturn", ABI_O32 }, + { "__vdso_rt_sigreturn", "off_rt_sigreturn", ABI_ALL }, + {} +}; + +static const char *program_name; +static const char *vdso_name; +static unsigned char elf_class; +static unsigned int elf_abi; +static bool need_swap; +static FILE *out_file; + +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +# define HOST_ORDER ELFDATA2LSB +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ +# define HOST_ORDER ELFDATA2MSB +#endif + +#define BUILD_SWAP(bits) \ + static uint##bits##_t swap_uint##bits(uint##bits##_t val) \ + { \ + return need_swap ? bswap_##bits(val) : val; \ + } + +BUILD_SWAP(16) +BUILD_SWAP(32) +BUILD_SWAP(64) + +#define __FUNC(name, bits) name##bits +#define _FUNC(name, bits) __FUNC(name, bits) +#define FUNC(name) _FUNC(name, ELF_BITS) + +#define __ELF(x, bits) Elf##bits##_##x +#define _ELF(x, bits) __ELF(x, bits) +#define ELF(x) _ELF(x, ELF_BITS) + +/* + * Include genvdso.h twice with ELF_BITS defined differently to get functions + * for both ELF32 and ELF64. + */ + +#define ELF_BITS 64 +#include "genvdso.h" +#undef ELF_BITS + +#define ELF_BITS 32 +#include "genvdso.h" +#undef ELF_BITS + +static void *map_vdso(const char *path, size_t *_size) +{ + int fd; + struct stat stat; + void *addr; + const Elf32_Ehdr *ehdr; + + fd = open(path, O_RDWR); + if (fd < 0) { + fprintf(stderr, "%s: Failed to open '%s': %s\n", program_name, + path, strerror(errno)); + return NULL; + } + + if (fstat(fd, &stat) != 0) { + fprintf(stderr, "%s: Failed to stat '%s': %s\n", program_name, + path, strerror(errno)); + return NULL; + } + + addr = mmap(NULL, stat.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, + 0); + if (addr == MAP_FAILED) { + fprintf(stderr, "%s: Failed to map '%s': %s\n", program_name, + path, strerror(errno)); + return NULL; + } + + /* ELF32/64 header formats are the same for the bits we're checking. */ + ehdr = addr; + + if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0) { + fprintf(stderr, "%s: '%s' is not an ELF file\n", program_name, + path); + return NULL; + } + + elf_class = ehdr->e_ident[EI_CLASS]; + switch (elf_class) { + case ELFCLASS32: + case ELFCLASS64: + break; + default: + fprintf(stderr, "%s: '%s' has invalid ELF class\n", + program_name, path); + return NULL; + } + + switch (ehdr->e_ident[EI_DATA]) { + case ELFDATA2LSB: + case ELFDATA2MSB: + need_swap = ehdr->e_ident[EI_DATA] != HOST_ORDER; + break; + default: + fprintf(stderr, "%s: '%s' has invalid ELF data order\n", + program_name, path); + return NULL; + } + + if (swap_uint16(ehdr->e_machine) != EM_MIPS) { + fprintf(stderr, + "%s: '%s' has invalid ELF machine (expected EM_MIPS)\n", + program_name, path); + return NULL; + } else if (swap_uint16(ehdr->e_type) != ET_DYN) { + fprintf(stderr, + "%s: '%s' has invalid ELF type (expected ET_DYN)\n", + program_name, path); + return NULL; + } + + *_size = stat.st_size; + return addr; +} + +static bool patch_vdso(const char *path, void *vdso) +{ + if (elf_class == ELFCLASS64) + return patch_vdso64(path, vdso); + else + return patch_vdso32(path, vdso); +} + +static bool get_symbols(const char *path, void *vdso) +{ + if (elf_class == ELFCLASS64) + return get_symbols64(path, vdso); + else + return get_symbols32(path, vdso); +} + +int main(int argc, char **argv) +{ + const char *dbg_vdso_path, *vdso_path, *out_path; + void *dbg_vdso, *vdso; + size_t dbg_vdso_size, vdso_size, i; + + program_name = argv[0]; + + if (argc < 4 || argc > 5) { + fprintf(stderr, + "Usage: %s <debug VDSO> <stripped VDSO> <output file> [<name>]\n", + program_name); + return EXIT_FAILURE; + } + + dbg_vdso_path = argv[1]; + vdso_path = argv[2]; + out_path = argv[3]; + vdso_name = (argc > 4) ? argv[4] : ""; + + dbg_vdso = map_vdso(dbg_vdso_path, &dbg_vdso_size); + if (!dbg_vdso) + return EXIT_FAILURE; + + vdso = map_vdso(vdso_path, &vdso_size); + if (!vdso) + return EXIT_FAILURE; + + /* Patch both the VDSOs' ABI flags sections. */ + if (!patch_vdso(dbg_vdso_path, dbg_vdso)) + return EXIT_FAILURE; + if (!patch_vdso(vdso_path, vdso)) + return EXIT_FAILURE; + + if (msync(dbg_vdso, dbg_vdso_size, MS_SYNC) != 0) { + fprintf(stderr, "%s: Failed to sync '%s': %s\n", program_name, + dbg_vdso_path, strerror(errno)); + return EXIT_FAILURE; + } else if (msync(vdso, vdso_size, MS_SYNC) != 0) { + fprintf(stderr, "%s: Failed to sync '%s': %s\n", program_name, + vdso_path, strerror(errno)); + return EXIT_FAILURE; + } + + out_file = fopen(out_path, "w"); + if (!out_file) { + fprintf(stderr, "%s: Failed to open '%s': %s\n", program_name, + out_path, strerror(errno)); + return EXIT_FAILURE; + } + + fprintf(out_file, "/* Automatically generated - do not edit */\n"); + fprintf(out_file, "#include <linux/linkage.h>\n"); + fprintf(out_file, "#include <linux/mm.h>\n"); + fprintf(out_file, "#include <asm/vdso.h>\n"); + + /* Write out the stripped VDSO data. */ + fprintf(out_file, + "static unsigned char vdso_data[PAGE_ALIGN(%zu)] __page_aligned_data = {\n\t", + vdso_size); + for (i = 0; i < vdso_size; i++) { + if (!(i % 10)) + fprintf(out_file, "\n\t"); + fprintf(out_file, "0x%02x, ", ((unsigned char *)vdso)[i]); + } + fprintf(out_file, "\n};\n"); + + /* Preallocate a page array. */ + fprintf(out_file, + "static struct page *vdso_pages[PAGE_ALIGN(%zu) / PAGE_SIZE];\n", + vdso_size); + + fprintf(out_file, "struct mips_vdso_image vdso_image%s%s = {\n", + (vdso_name[0]) ? "_" : "", vdso_name); + fprintf(out_file, "\t.data = vdso_data,\n"); + fprintf(out_file, "\t.size = PAGE_ALIGN(%zu),\n", vdso_size); + fprintf(out_file, "\t.mapping = {\n"); + fprintf(out_file, "\t\t.name = \"[vdso]\",\n"); + fprintf(out_file, "\t\t.pages = vdso_pages,\n"); + fprintf(out_file, "\t},\n"); + + /* Calculate and write symbol offsets to <output file> */ + if (!get_symbols(dbg_vdso_path, dbg_vdso)) { + unlink(out_path); + return EXIT_FAILURE; + } + + fprintf(out_file, "};\n"); + + return EXIT_SUCCESS; +} diff --git a/arch/mips/vdso/genvdso.h b/arch/mips/vdso/genvdso.h new file mode 100644 index 000000000000..94334727059a --- /dev/null +++ b/arch/mips/vdso/genvdso.h @@ -0,0 +1,187 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +static inline bool FUNC(patch_vdso)(const char *path, void *vdso) +{ + const ELF(Ehdr) *ehdr = vdso; + void *shdrs; + ELF(Shdr) *shdr; + char *shstrtab, *name; + uint16_t sh_count, sh_entsize, i; + unsigned int local_gotno, symtabno, gotsym; + ELF(Dyn) *dyn = NULL; + + shdrs = vdso + FUNC(swap_uint)(ehdr->e_shoff); + sh_count = swap_uint16(ehdr->e_shnum); + sh_entsize = swap_uint16(ehdr->e_shentsize); + + shdr = shdrs + (sh_entsize * swap_uint16(ehdr->e_shstrndx)); + shstrtab = vdso + FUNC(swap_uint)(shdr->sh_offset); + + for (i = 0; i < sh_count; i++) { + shdr = shdrs + (i * sh_entsize); + name = shstrtab + swap_uint32(shdr->sh_name); + + /* + * Ensure there are no relocation sections - ld.so does not + * relocate the VDSO so if there are relocations things will + * break. + */ + switch (swap_uint32(shdr->sh_type)) { + case SHT_REL: + case SHT_RELA: + fprintf(stderr, + "%s: '%s' contains relocation sections\n", + program_name, path); + return false; + case SHT_DYNAMIC: + dyn = vdso + FUNC(swap_uint)(shdr->sh_offset); + break; + } + + /* Check for existing sections. */ + if (strcmp(name, ".MIPS.abiflags") == 0) { + fprintf(stderr, + "%s: '%s' already contains a '.MIPS.abiflags' section\n", + program_name, path); + return false; + } + + if (strcmp(name, ".mips_abiflags") == 0) { + strcpy(name, ".MIPS.abiflags"); + shdr->sh_type = swap_uint32(SHT_MIPS_ABIFLAGS); + shdr->sh_entsize = shdr->sh_size; + } + } + + /* + * Ensure the GOT has no entries other than the standard 2, for the same + * reason we check that there's no relocation sections above. + * The standard two entries are: + * - Lazy resolver + * - Module pointer + */ + if (dyn) { + local_gotno = symtabno = gotsym = 0; + + while (FUNC(swap_uint)(dyn->d_tag) != DT_NULL) { + switch (FUNC(swap_uint)(dyn->d_tag)) { + /* + * This member holds the number of local GOT entries. + */ + case DT_MIPS_LOCAL_GOTNO: + local_gotno = FUNC(swap_uint)(dyn->d_un.d_val); + break; + /* + * This member holds the number of entries in the + * .dynsym section. + */ + case DT_MIPS_SYMTABNO: + symtabno = FUNC(swap_uint)(dyn->d_un.d_val); + break; + /* + * This member holds the index of the first dynamic + * symbol table entry that corresponds to an entry in + * the GOT. + */ + case DT_MIPS_GOTSYM: + gotsym = FUNC(swap_uint)(dyn->d_un.d_val); + break; + } + + dyn++; + } + + if (local_gotno > 2 || symtabno - gotsym) { + fprintf(stderr, + "%s: '%s' contains unexpected GOT entries\n", + program_name, path); + return false; + } + } + + return true; +} + +static inline bool FUNC(get_symbols)(const char *path, void *vdso) +{ + const ELF(Ehdr) *ehdr = vdso; + void *shdrs, *symtab; + ELF(Shdr) *shdr; + const ELF(Sym) *sym; + char *strtab, *name; + uint16_t sh_count, sh_entsize, st_count, st_entsize, i, j; + uint64_t offset; + uint32_t flags; + + shdrs = vdso + FUNC(swap_uint)(ehdr->e_shoff); + sh_count = swap_uint16(ehdr->e_shnum); + sh_entsize = swap_uint16(ehdr->e_shentsize); + + for (i = 0; i < sh_count; i++) { + shdr = shdrs + (i * sh_entsize); + + if (swap_uint32(shdr->sh_type) == SHT_SYMTAB) + break; + } + + if (i == sh_count) { + fprintf(stderr, "%s: '%s' has no symbol table\n", program_name, + path); + return false; + } + + /* Get flags */ + flags = swap_uint32(ehdr->e_flags); + if (elf_class == ELFCLASS64) + elf_abi = ABI_N64; + else if (flags & EF_MIPS_ABI2) + elf_abi = ABI_N32; + else + elf_abi = ABI_O32; + + /* Get symbol table. */ + symtab = vdso + FUNC(swap_uint)(shdr->sh_offset); + st_entsize = FUNC(swap_uint)(shdr->sh_entsize); + st_count = FUNC(swap_uint)(shdr->sh_size) / st_entsize; + + /* Get string table. */ + shdr = shdrs + (swap_uint32(shdr->sh_link) * sh_entsize); + strtab = vdso + FUNC(swap_uint)(shdr->sh_offset); + + /* Write offsets for symbols needed by the kernel. */ + for (i = 0; vdso_symbols[i].name; i++) { + if (!(vdso_symbols[i].abis & elf_abi)) + continue; + + for (j = 0; j < st_count; j++) { + sym = symtab + (j * st_entsize); + name = strtab + swap_uint32(sym->st_name); + + if (!strcmp(name, vdso_symbols[i].name)) { + offset = FUNC(swap_uint)(sym->st_value); + + fprintf(out_file, + "\t.%s = 0x%" PRIx64 ",\n", + vdso_symbols[i].offset_name, offset); + break; + } + } + + if (j == st_count) { + fprintf(stderr, + "%s: '%s' is missing required symbol '%s'\n", + program_name, path, vdso_symbols[i].name); + return false; + } + } + + return true; +} diff --git a/arch/mips/vdso/sigreturn.S b/arch/mips/vdso/sigreturn.S new file mode 100644 index 000000000000..715bf5993529 --- /dev/null +++ b/arch/mips/vdso/sigreturn.S @@ -0,0 +1,49 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include "vdso.h" + +#include <uapi/asm/unistd.h> + +#include <asm/regdef.h> +#include <asm/asm.h> + + .section .text + .cfi_sections .debug_frame + +LEAF(__vdso_rt_sigreturn) + .cfi_startproc + .frame sp, 0, ra + .mask 0x00000000, 0 + .fmask 0x00000000, 0 + .cfi_signal_frame + + li v0, __NR_rt_sigreturn + syscall + + .cfi_endproc + END(__vdso_rt_sigreturn) + +#if _MIPS_SIM == _MIPS_SIM_ABI32 + +LEAF(__vdso_sigreturn) + .cfi_startproc + .frame sp, 0, ra + .mask 0x00000000, 0 + .fmask 0x00000000, 0 + .cfi_signal_frame + + li v0, __NR_sigreturn + syscall + + .cfi_endproc + END(__vdso_sigreturn) + +#endif diff --git a/arch/mips/vdso/vdso.h b/arch/mips/vdso/vdso.h new file mode 100644 index 000000000000..0bb6b1adc385 --- /dev/null +++ b/arch/mips/vdso/vdso.h @@ -0,0 +1,80 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <asm/sgidefs.h> + +#if _MIPS_SIM != _MIPS_SIM_ABI64 && defined(CONFIG_64BIT) + +/* Building 32-bit VDSO for the 64-bit kernel. Fake a 32-bit Kconfig. */ +#undef CONFIG_64BIT +#define CONFIG_32BIT 1 +#ifndef __ASSEMBLY__ +#include <asm-generic/atomic64.h> +#endif +#endif + +#ifndef __ASSEMBLY__ + +#include <asm/asm.h> +#include <asm/page.h> +#include <asm/vdso.h> + +static inline unsigned long get_vdso_base(void) +{ + unsigned long addr; + + /* + * We can't use cpu_has_mips_r6 since it needs the cpu_data[] + * kernel symbol. + */ +#ifdef CONFIG_CPU_MIPSR6 + /* + * lapc <symbol> is an alias to addiupc reg, <symbol> - . + * + * We can't use addiupc because there is no label-label + * support for the addiupc reloc + */ + __asm__("lapc %0, _start \n" + : "=r" (addr) : :); +#else + /* + * Get the base load address of the VDSO. We have to avoid generating + * relocations and references to the GOT because ld.so does not peform + * relocations on the VDSO. We use the current offset from the VDSO base + * and perform a PC-relative branch which gives the absolute address in + * ra, and take the difference. The assembler chokes on + * "li %0, _start - .", so embed the offset as a word and branch over + * it. + * + */ + + __asm__( + " .set push \n" + " .set noreorder \n" + " bal 1f \n" + " nop \n" + " .word _start - . \n" + "1: lw %0, 0($31) \n" + " " STR(PTR_ADDU) " %0, $31, %0 \n" + " .set pop \n" + : "=r" (addr) + : + : "$31"); +#endif /* CONFIG_CPU_MIPSR6 */ + + return addr; +} + +static inline const union mips_vdso_data *get_vdso_data(void) +{ + return (const union mips_vdso_data *)(get_vdso_base() - PAGE_SIZE); +} + +#endif /* __ASSEMBLY__ */ diff --git a/arch/mips/vdso/vdso.lds.S b/arch/mips/vdso/vdso.lds.S new file mode 100644 index 000000000000..21655b6fefc5 --- /dev/null +++ b/arch/mips/vdso/vdso.lds.S @@ -0,0 +1,100 @@ +/* + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith <alex.smith@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <asm/sgidefs.h> + +#if _MIPS_SIM == _MIPS_SIM_ABI64 +OUTPUT_FORMAT("elf64-tradlittlemips", "elf64-tradbigmips", "elf64-tradlittlemips") +#elif _MIPS_SIM == _MIPS_SIM_NABI32 +OUTPUT_FORMAT("elf32-ntradlittlemips", "elf32-ntradbigmips", "elf32-ntradlittlemips") +#else +OUTPUT_FORMAT("elf32-tradlittlemips", "elf32-tradbigmips", "elf32-tradlittlemips") +#endif + +OUTPUT_ARCH(mips) + +SECTIONS +{ + PROVIDE(_start = .); + . = SIZEOF_HEADERS; + + /* + * In order to retain compatibility with older toolchains we provide the + * ABI flags section ourself. Newer assemblers will automatically + * generate .MIPS.abiflags sections so we discard such input sections, + * and then manually define our own section here. genvdso will patch + * this section to have the correct name/type. + */ + .mips_abiflags : { *(.mips_abiflags) } :text :abiflags + + .reginfo : { *(.reginfo) } :text :reginfo + + .hash : { *(.hash) } :text + .gnu.hash : { *(.gnu.hash) } + .dynsym : { *(.dynsym) } + .dynstr : { *(.dynstr) } + .gnu.version : { *(.gnu.version) } + .gnu.version_d : { *(.gnu.version_d) } + .gnu.version_r : { *(.gnu.version_r) } + + .note : { *(.note.*) } :text :note + + .text : { *(.text*) } :text + PROVIDE (__etext = .); + PROVIDE (_etext = .); + PROVIDE (etext = .); + + .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr + .eh_frame : { KEEP (*(.eh_frame)) } :text + + .dynamic : { *(.dynamic) } :text :dynamic + + .rodata : { *(.rodata*) } :text + + _end = .; + PROVIDE(end = .); + + /DISCARD/ : { + *(.MIPS.abiflags) + *(.gnu.attributes) + *(.note.GNU-stack) + *(.data .data.* .gnu.linkonce.d.* .sdata*) + *(.bss .sbss .dynbss .dynsbss) + } +} + +PHDRS +{ + /* + * Provide a PT_MIPS_ABIFLAGS header to assign the ABI flags section + * to. We can specify the header type directly here so no modification + * is needed later on. + */ + abiflags 0x70000003; + + /* + * The ABI flags header must exist directly after the PT_INTERP header, + * so we must explicitly place the PT_MIPS_REGINFO header after it to + * stop the linker putting one in at the start. + */ + reginfo 0x70000000; + + text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ + dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ + note PT_NOTE FLAGS(4); /* PF_R */ + eh_frame_hdr PT_GNU_EH_FRAME; +} + +VERSION +{ + LINUX_2.6 { + local: *; + }; +} |