diff options
Diffstat (limited to 'arch/tile/kernel/ptrace.c')
| -rw-r--r-- | arch/tile/kernel/ptrace.c | 140 |
1 files changed, 113 insertions, 27 deletions
diff --git a/arch/tile/kernel/ptrace.c b/arch/tile/kernel/ptrace.c index e92e40527d6..9835312d5a9 100644 --- a/arch/tile/kernel/ptrace.c +++ b/arch/tile/kernel/ptrace.c @@ -19,7 +19,10 @@ #include <linux/kprobes.h> #include <linux/compat.h> #include <linux/uaccess.h> +#include <linux/regset.h> +#include <linux/elf.h> #include <asm/traps.h> +#include <arch/chip.h> void user_enable_single_step(struct task_struct *child) { @@ -45,6 +48,100 @@ void ptrace_disable(struct task_struct *child) clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); } +/* + * Get registers from task and ready the result for userspace. + * Note that we localize the API issues to getregs() and putregs() at + * some cost in performance, e.g. we need a full pt_regs copy for + * PEEKUSR, and two copies for POKEUSR. But in general we expect + * GETREGS/PUTREGS to be the API of choice anyway. + */ +static char *getregs(struct task_struct *child, struct pt_regs *uregs) +{ + *uregs = *task_pt_regs(child); + + /* Set up flags ABI bits. */ + uregs->flags = 0; +#ifdef CONFIG_COMPAT + if (task_thread_info(child)->status & TS_COMPAT) + uregs->flags |= PT_FLAGS_COMPAT; +#endif + + return (char *)uregs; +} + +/* Put registers back to task. */ +static void putregs(struct task_struct *child, struct pt_regs *uregs) +{ + struct pt_regs *regs = task_pt_regs(child); + + /* Don't allow overwriting the kernel-internal flags word. */ + uregs->flags = regs->flags; + + /* Only allow setting the ICS bit in the ex1 word. */ + uregs->ex1 = PL_ICS_EX1(USER_PL, EX1_ICS(uregs->ex1)); + + *regs = *uregs; +} + +enum tile_regset { + REGSET_GPR, +}; + +static int tile_gpr_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + struct pt_regs regs; + + getregs(target, ®s); + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, ®s, 0, + sizeof(regs)); +} + +static int tile_gpr_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + struct pt_regs regs; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, ®s, 0, + sizeof(regs)); + if (ret) + return ret; + + putregs(target, ®s); + + return 0; +} + +static const struct user_regset tile_user_regset[] = { + [REGSET_GPR] = { + .core_note_type = NT_PRSTATUS, + .n = ELF_NGREG, + .size = sizeof(elf_greg_t), + .align = sizeof(elf_greg_t), + .get = tile_gpr_get, + .set = tile_gpr_set, + }, +}; + +static const struct user_regset_view tile_user_regset_view = { + .name = CHIP_ARCH_NAME, + .e_machine = ELF_ARCH, + .ei_osabi = ELF_OSABI, + .regsets = tile_user_regset, + .n = ARRAY_SIZE(tile_user_regset), +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &tile_user_regset_view; +} + long arch_ptrace(struct task_struct *child, long request, unsigned long addr, unsigned long data) { @@ -53,14 +150,13 @@ long arch_ptrace(struct task_struct *child, long request, long ret = -EIO; char *childreg; struct pt_regs copyregs; - int ex1_offset; switch (request) { case PTRACE_PEEKUSR: /* Read register from pt_regs. */ if (addr >= PTREGS_SIZE) break; - childreg = (char *)task_pt_regs(child) + addr; + childreg = getregs(child, ©regs) + addr; #ifdef CONFIG_COMPAT if (is_compat_task()) { if (addr & (sizeof(compat_long_t)-1)) @@ -79,17 +175,7 @@ long arch_ptrace(struct task_struct *child, long request, case PTRACE_POKEUSR: /* Write register in pt_regs. */ if (addr >= PTREGS_SIZE) break; - childreg = (char *)task_pt_regs(child) + addr; - - /* Guard against overwrites of the privilege level. */ - ex1_offset = PTREGS_OFFSET_EX1; -#if defined(CONFIG_COMPAT) && defined(__BIG_ENDIAN) - if (is_compat_task()) /* point at low word */ - ex1_offset += sizeof(compat_long_t); -#endif - if (addr == ex1_offset) - data = PL_ICS_EX1(USER_PL, EX1_ICS(data)); - + childreg = getregs(child, ©regs) + addr; #ifdef CONFIG_COMPAT if (is_compat_task()) { if (addr & (sizeof(compat_long_t)-1)) @@ -102,24 +188,20 @@ long arch_ptrace(struct task_struct *child, long request, break; *(long *)childreg = data; } + putregs(child, ©regs); ret = 0; break; case PTRACE_GETREGS: /* Get all registers from the child. */ - if (copy_to_user(datap, task_pt_regs(child), - sizeof(struct pt_regs)) == 0) { - ret = 0; - } + ret = copy_regset_to_user(child, &tile_user_regset_view, + REGSET_GPR, 0, + sizeof(struct pt_regs), datap); break; case PTRACE_SETREGS: /* Set all registers in the child. */ - if (copy_from_user(©regs, datap, - sizeof(struct pt_regs)) == 0) { - copyregs.ex1 = - PL_ICS_EX1(USER_PL, EX1_ICS(copyregs.ex1)); - *task_pt_regs(child) = copyregs; - ret = 0; - } + ret = copy_regset_from_user(child, &tile_user_regset_view, + REGSET_GPR, 0, + sizeof(struct pt_regs), datap); break; case PTRACE_GETFPREGS: /* Get the child FPU state. */ @@ -128,12 +210,16 @@ long arch_ptrace(struct task_struct *child, long request, case PTRACE_SETOPTIONS: /* Support TILE-specific ptrace options. */ - child->ptrace &= ~PT_TRACE_MASK_TILE; + BUILD_BUG_ON(PTRACE_O_MASK_TILE & PTRACE_O_MASK); tmp = data & PTRACE_O_MASK_TILE; data &= ~PTRACE_O_MASK_TILE; ret = ptrace_request(child, request, addr, data); - if (tmp & PTRACE_O_TRACEMIGRATE) - child->ptrace |= PT_TRACE_MIGRATE; + if (ret == 0) { + unsigned int flags = child->ptrace; + flags &= ~(PTRACE_O_MASK_TILE << PT_OPT_FLAG_SHIFT); + flags |= (tmp << PT_OPT_FLAG_SHIFT); + child->ptrace = flags; + } break; default: |