diff options
Diffstat (limited to 'target/arm/arch_dump.c')
| -rw-r--r-- | target/arm/arch_dump.c | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/target/arm/arch_dump.c b/target/arm/arch_dump.c new file mode 100644 index 0000000..1a9861f --- /dev/null +++ b/target/arm/arch_dump.c @@ -0,0 +1,337 @@ +/* Support for writing ELF notes for ARM architectures + * + * Copyright (C) 2015 Red Hat Inc. + * + * Author: Andrew Jones <drjones@redhat.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 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 "qemu/osdep.h" +#include "cpu.h" +#include "elf.h" +#include "sysemu/dump.h" + +/* struct user_pt_regs from arch/arm64/include/uapi/asm/ptrace.h */ +struct aarch64_user_regs { + uint64_t regs[31]; + uint64_t sp; + uint64_t pc; + uint64_t pstate; +} QEMU_PACKED; + +QEMU_BUILD_BUG_ON(sizeof(struct aarch64_user_regs) != 272); + +/* struct elf_prstatus from include/uapi/linux/elfcore.h */ +struct aarch64_elf_prstatus { + char pad1[32]; /* 32 == offsetof(struct elf_prstatus, pr_pid) */ + uint32_t pr_pid; + char pad2[76]; /* 76 == offsetof(struct elf_prstatus, pr_reg) - + offsetof(struct elf_prstatus, pr_ppid) */ + struct aarch64_user_regs pr_reg; + uint32_t pr_fpvalid; + char pad3[4]; +} QEMU_PACKED; + +QEMU_BUILD_BUG_ON(sizeof(struct aarch64_elf_prstatus) != 392); + +/* struct user_fpsimd_state from arch/arm64/include/uapi/asm/ptrace.h + * + * While the vregs member of user_fpsimd_state is of type __uint128_t, + * QEMU uses an array of uint64_t, where the high half of the 128-bit + * value is always in the 2n+1'th index. Thus we also break the 128- + * bit values into two halves in this reproduction of user_fpsimd_state. + */ +struct aarch64_user_vfp_state { + uint64_t vregs[64]; + uint32_t fpsr; + uint32_t fpcr; + char pad[8]; +} QEMU_PACKED; + +QEMU_BUILD_BUG_ON(sizeof(struct aarch64_user_vfp_state) != 528); + +struct aarch64_note { + Elf64_Nhdr hdr; + char name[8]; /* align_up(sizeof("CORE"), 4) */ + union { + struct aarch64_elf_prstatus prstatus; + struct aarch64_user_vfp_state vfp; + }; +} QEMU_PACKED; + +#define AARCH64_NOTE_HEADER_SIZE offsetof(struct aarch64_note, prstatus) +#define AARCH64_PRSTATUS_NOTE_SIZE \ + (AARCH64_NOTE_HEADER_SIZE + sizeof(struct aarch64_elf_prstatus)) +#define AARCH64_PRFPREG_NOTE_SIZE \ + (AARCH64_NOTE_HEADER_SIZE + sizeof(struct aarch64_user_vfp_state)) + +static void aarch64_note_init(struct aarch64_note *note, DumpState *s, + const char *name, Elf64_Word namesz, + Elf64_Word type, Elf64_Word descsz) +{ + memset(note, 0, sizeof(*note)); + + note->hdr.n_namesz = cpu_to_dump32(s, namesz); + note->hdr.n_descsz = cpu_to_dump32(s, descsz); + note->hdr.n_type = cpu_to_dump32(s, type); + + memcpy(note->name, name, namesz); +} + +static int aarch64_write_elf64_prfpreg(WriteCoreDumpFunction f, + CPUARMState *env, int cpuid, + DumpState *s) +{ + struct aarch64_note note; + int ret, i; + + aarch64_note_init(¬e, s, "CORE", 5, NT_PRFPREG, sizeof(note.vfp)); + + for (i = 0; i < 64; ++i) { + note.vfp.vregs[i] = cpu_to_dump64(s, float64_val(env->vfp.regs[i])); + } + + if (s->dump_info.d_endian == ELFDATA2MSB) { + /* For AArch64 we must always swap the vfp.regs's 2n and 2n+1 + * entries when generating BE notes, because even big endian + * hosts use 2n+1 for the high half. + */ + for (i = 0; i < 32; ++i) { + uint64_t tmp = note.vfp.vregs[2*i]; + note.vfp.vregs[2*i] = note.vfp.vregs[2*i+1]; + note.vfp.vregs[2*i+1] = tmp; + } + } + + note.vfp.fpsr = cpu_to_dump32(s, vfp_get_fpsr(env)); + note.vfp.fpcr = cpu_to_dump32(s, vfp_get_fpcr(env)); + + ret = f(¬e, AARCH64_PRFPREG_NOTE_SIZE, s); + if (ret < 0) { + return -1; + } + + return 0; +} + +int arm_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs, + int cpuid, void *opaque) +{ + struct aarch64_note note; + CPUARMState *env = &ARM_CPU(cs)->env; + DumpState *s = opaque; + uint64_t pstate, sp; + int ret, i; + + aarch64_note_init(¬e, s, "CORE", 5, NT_PRSTATUS, sizeof(note.prstatus)); + + note.prstatus.pr_pid = cpu_to_dump32(s, cpuid); + note.prstatus.pr_fpvalid = cpu_to_dump32(s, 1); + + if (!is_a64(env)) { + aarch64_sync_32_to_64(env); + pstate = cpsr_read(env); + sp = 0; + } else { + pstate = pstate_read(env); + sp = env->xregs[31]; + } + + for (i = 0; i < 31; ++i) { + note.prstatus.pr_reg.regs[i] = cpu_to_dump64(s, env->xregs[i]); + } + note.prstatus.pr_reg.sp = cpu_to_dump64(s, sp); + note.prstatus.pr_reg.pc = cpu_to_dump64(s, env->pc); + note.prstatus.pr_reg.pstate = cpu_to_dump64(s, pstate); + + ret = f(¬e, AARCH64_PRSTATUS_NOTE_SIZE, s); + if (ret < 0) { + return -1; + } + + return aarch64_write_elf64_prfpreg(f, env, cpuid, s); +} + +/* struct pt_regs from arch/arm/include/asm/ptrace.h */ +struct arm_user_regs { + uint32_t regs[17]; + char pad[4]; +} QEMU_PACKED; + +QEMU_BUILD_BUG_ON(sizeof(struct arm_user_regs) != 72); + +/* struct elf_prstatus from include/uapi/linux/elfcore.h */ +struct arm_elf_prstatus { + char pad1[24]; /* 24 == offsetof(struct elf_prstatus, pr_pid) */ + uint32_t pr_pid; + char pad2[44]; /* 44 == offsetof(struct elf_prstatus, pr_reg) - + offsetof(struct elf_prstatus, pr_ppid) */ + struct arm_user_regs pr_reg; + uint32_t pr_fpvalid; +} QEMU_PACKED arm_elf_prstatus; + +QEMU_BUILD_BUG_ON(sizeof(struct arm_elf_prstatus) != 148); + +/* struct user_vfp from arch/arm/include/asm/user.h */ +struct arm_user_vfp_state { + uint64_t vregs[32]; + uint32_t fpscr; +} QEMU_PACKED; + +QEMU_BUILD_BUG_ON(sizeof(struct arm_user_vfp_state) != 260); + +struct arm_note { + Elf32_Nhdr hdr; + char name[8]; /* align_up(sizeof("LINUX"), 4) */ + union { + struct arm_elf_prstatus prstatus; + struct arm_user_vfp_state vfp; + }; +} QEMU_PACKED; + +#define ARM_NOTE_HEADER_SIZE offsetof(struct arm_note, prstatus) +#define ARM_PRSTATUS_NOTE_SIZE \ + (ARM_NOTE_HEADER_SIZE + sizeof(struct arm_elf_prstatus)) +#define ARM_VFP_NOTE_SIZE \ + (ARM_NOTE_HEADER_SIZE + sizeof(struct arm_user_vfp_state)) + +static void arm_note_init(struct arm_note *note, DumpState *s, + const char *name, Elf32_Word namesz, + Elf32_Word type, Elf32_Word descsz) +{ + memset(note, 0, sizeof(*note)); + + note->hdr.n_namesz = cpu_to_dump32(s, namesz); + note->hdr.n_descsz = cpu_to_dump32(s, descsz); + note->hdr.n_type = cpu_to_dump32(s, type); + + memcpy(note->name, name, namesz); +} + +static int arm_write_elf32_vfp(WriteCoreDumpFunction f, CPUARMState *env, + int cpuid, DumpState *s) +{ + struct arm_note note; + int ret, i; + + arm_note_init(¬e, s, "LINUX", 6, NT_ARM_VFP, sizeof(note.vfp)); + + for (i = 0; i < 32; ++i) { + note.vfp.vregs[i] = cpu_to_dump64(s, float64_val(env->vfp.regs[i])); + } + + note.vfp.fpscr = cpu_to_dump32(s, vfp_get_fpscr(env)); + + ret = f(¬e, ARM_VFP_NOTE_SIZE, s); + if (ret < 0) { + return -1; + } + + return 0; +} + +int arm_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs, + int cpuid, void *opaque) +{ + struct arm_note note; + CPUARMState *env = &ARM_CPU(cs)->env; + DumpState *s = opaque; + int ret, i, fpvalid = !!arm_feature(env, ARM_FEATURE_VFP); + + arm_note_init(¬e, s, "CORE", 5, NT_PRSTATUS, sizeof(note.prstatus)); + + note.prstatus.pr_pid = cpu_to_dump32(s, cpuid); + note.prstatus.pr_fpvalid = cpu_to_dump32(s, fpvalid); + + for (i = 0; i < 16; ++i) { + note.prstatus.pr_reg.regs[i] = cpu_to_dump32(s, env->regs[i]); + } + note.prstatus.pr_reg.regs[16] = cpu_to_dump32(s, cpsr_read(env)); + + ret = f(¬e, ARM_PRSTATUS_NOTE_SIZE, s); + if (ret < 0) { + return -1; + } else if (fpvalid) { + return arm_write_elf32_vfp(f, env, cpuid, s); + } + + return 0; +} + +int cpu_get_dump_info(ArchDumpInfo *info, + const GuestPhysBlockList *guest_phys_blocks) +{ + ARMCPU *cpu = ARM_CPU(first_cpu); + CPUARMState *env = &cpu->env; + GuestPhysBlock *block; + hwaddr lowest_addr = ULLONG_MAX; + + /* Take a best guess at the phys_base. If we get it wrong then crash + * will need '--machdep phys_offset=<phys-offset>' added to its command + * line, which isn't any worse than assuming we can use zero, but being + * wrong. This is the same algorithm the crash utility uses when + * attempting to guess as it loads non-dumpfile formatted files. + */ + QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) { + if (block->target_start < lowest_addr) { + lowest_addr = block->target_start; + } + } + + if (arm_feature(env, ARM_FEATURE_AARCH64)) { + info->d_machine = EM_AARCH64; + info->d_class = ELFCLASS64; + info->page_size = (1 << 16); /* aarch64 max pagesize */ + if (lowest_addr != ULLONG_MAX) { + info->phys_base = lowest_addr; + } + } else { + info->d_machine = EM_ARM; + info->d_class = ELFCLASS32; + info->page_size = (1 << 12); + if (lowest_addr < UINT_MAX) { + info->phys_base = lowest_addr; + } + } + + /* We assume the relevant endianness is that of EL1; this is right + * for kernels, but might give the wrong answer if you're trying to + * dump a hypervisor that happens to be running an opposite-endian + * kernel. + */ + info->d_endian = (env->cp15.sctlr_el[1] & SCTLR_EE) != 0 + ? ELFDATA2MSB : ELFDATA2LSB; + + return 0; +} + +ssize_t cpu_get_note_size(int class, int machine, int nr_cpus) +{ + ARMCPU *cpu = ARM_CPU(first_cpu); + CPUARMState *env = &cpu->env; + size_t note_size; + + if (class == ELFCLASS64) { + note_size = AARCH64_PRSTATUS_NOTE_SIZE; + note_size += AARCH64_PRFPREG_NOTE_SIZE; + } else { + note_size = ARM_PRSTATUS_NOTE_SIZE; + if (arm_feature(env, ARM_FEATURE_VFP)) { + note_size += ARM_VFP_NOTE_SIZE; + } + } + + return note_size * nr_cpus; +} |