diff options
Diffstat (limited to 'arch/h8300/kernel/ptrace.c')
-rw-r--r-- | arch/h8300/kernel/ptrace.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/arch/h8300/kernel/ptrace.c b/arch/h8300/kernel/ptrace.c new file mode 100644 index 000000000000..92075544a19a --- /dev/null +++ b/arch/h8300/kernel/ptrace.c @@ -0,0 +1,203 @@ +/* + * linux/arch/h8300/kernel/ptrace.c + * + * Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp> + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/audit.h> +#include <linux/tracehook.h> +#include <linux/regset.h> +#include <linux/elf.h> + +#define CCR_MASK 0x6f /* mode/imask not set */ +#define EXR_MASK 0x80 /* modify only T */ + +#define PT_REG(r) offsetof(struct pt_regs, r) + +extern void user_disable_single_step(struct task_struct *child); + +/* Mapping from PT_xxx to the stack offset at which the register is + saved. Notice that usp has no stack-slot and needs to be treated + specially (see get_reg/put_reg below). */ +static const int register_offset[] = { + PT_REG(er1), PT_REG(er2), PT_REG(er3), PT_REG(er4), + PT_REG(er5), PT_REG(er6), PT_REG(er0), -1, + PT_REG(orig_er0), PT_REG(ccr), PT_REG(pc), +#if defined(CONFIG_CPU_H8S) + PT_REG(exr), +#endif +}; + +/* read register */ +long h8300_get_reg(struct task_struct *task, int regno) +{ + switch (regno) { + case PT_USP: + return task->thread.usp + sizeof(long)*2; + case PT_CCR: + case PT_EXR: + return *(unsigned short *)(task->thread.esp0 + + register_offset[regno]); + default: + return *(unsigned long *)(task->thread.esp0 + + register_offset[regno]); + } +} + +int h8300_put_reg(struct task_struct *task, int regno, unsigned long data) +{ + unsigned short oldccr; + unsigned short oldexr; + + switch (regno) { + case PT_USP: + task->thread.usp = data - sizeof(long)*2; + case PT_CCR: + oldccr = *(unsigned short *)(task->thread.esp0 + + register_offset[regno]); + oldccr &= ~CCR_MASK; + data &= CCR_MASK; + data |= oldccr; + *(unsigned short *)(task->thread.esp0 + + register_offset[regno]) = data; + break; + case PT_EXR: + oldexr = *(unsigned short *)(task->thread.esp0 + + register_offset[regno]); + oldccr &= ~EXR_MASK; + data &= EXR_MASK; + data |= oldexr; + *(unsigned short *)(task->thread.esp0 + + register_offset[regno]) = data; + break; + default: + *(unsigned long *)(task->thread.esp0 + + register_offset[regno]) = data; + break; + } + return 0; +} + +static int regs_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + int r; + struct user_regs_struct regs; + long *reg = (long *)®s; + + /* build user regs in buffer */ + for (r = 0; r < ARRAY_SIZE(register_offset); r++) + *reg++ = h8300_get_reg(target, r); + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + ®s, 0, sizeof(regs)); +} + +static int regs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int r; + int ret; + struct user_regs_struct regs; + long *reg; + + /* build user regs in buffer */ + for (reg = (long *)®s, r = 0; r < ARRAY_SIZE(register_offset); r++) + *reg++ = h8300_get_reg(target, r); + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + ®s, 0, sizeof(regs)); + if (ret) + return ret; + + /* write back to pt_regs */ + for (reg = (long *)®s, r = 0; r < ARRAY_SIZE(register_offset); r++) + h8300_put_reg(target, r, *reg++); + return 0; +} + +enum h8300_regset { + REGSET_GENERAL, +}; + +static const struct user_regset h8300_regsets[] = { + [REGSET_GENERAL] = { + .core_note_type = NT_PRSTATUS, + .n = ELF_NGREG, + .size = sizeof(long), + .align = sizeof(long), + .get = regs_get, + .set = regs_set, + }, +}; + +static const struct user_regset_view user_h8300_native_view = { + .name = "h8300", + .e_machine = EM_H8_300, + .regsets = h8300_regsets, + .n = ARRAY_SIZE(h8300_regsets), +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &user_h8300_native_view; +} + +void ptrace_disable(struct task_struct *child) +{ + user_disable_single_step(child); +} + +long arch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + int ret; + + switch (request) { + default: + ret = ptrace_request(child, request, addr, data); + break; + } + return ret; +} + +asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) +{ + long ret = 0; + + if (test_thread_flag(TIF_SYSCALL_TRACE) && + tracehook_report_syscall_entry(regs)) + /* + * Tracing decided this syscall should not happen. + * We'll return a bogus call number to get an ENOSYS + * error, but leave the original number in regs->regs[0]. + */ + ret = -1L; + + audit_syscall_entry(regs->er1, regs->er2, regs->er3, + regs->er4, regs->er5); + + return ret ?: regs->er0; +} + +asmlinkage void do_syscall_trace_leave(struct pt_regs *regs) +{ + int step; + + audit_syscall_exit(regs); + + step = test_thread_flag(TIF_SINGLESTEP); + if (step || test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall_exit(regs, step); +} |