runtime/linux/uprobes2/uprobes_x86.h - systemtap

Data types defined

Functions defined

Macros defined

Source code

#ifndef _ASM_UPROBES_H
#define _ASM_UPROBES_H
/*
*  Userspace Probes (UProbes)
*  uprobes.h
*
* 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/>.
*
* Copyright (C) IBM Corporation, 2008
*/
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <asm/thread_info.h>

/* Normally defined in Kconfig */
#define CONFIG_URETPROBES 1
#define CONFIG_UPROBES_SSOL 1

typedef u8 uprobe_opcode_t;
#define BREAKPOINT_INSTRUCTION    0xcc
#define BP_INSN_SIZE 1
#define MAX_UINSN_BYTES 16

// SLOT_IP should be 16 for 64-bit apps (include/asm-x86_64/elf.h)
// but 12 for 32-bit apps (arch/x86_64/ia32/ia32_binfmt.c)
#ifdef CONFIG_X86_32
#define SLOT_IP(tsk) 12
#else
#define SLOT_IP(tsk) (test_tsk_thread_flag(tsk, TIF_IA32) ? 12 : 16)
#endif

#define BREAKPOINT_SIGNAL SIGTRAP
#define SSTEP_SIGNAL SIGTRAP

/* Architecture specific switch for where the IP points after a bp hit */
#define ARCH_BP_INST_PTR(inst_ptr)    (inst_ptr - BP_INSN_SIZE)

#define UPFIX_RIP_RAX 0x1    /* (%rip) insn rewritten to use (%rax) */
#define UPFIX_RIP_RCX 0x2    /* (%rip) insn rewritten to use (%rcx) */
#define UPFIX_ABS_IP  0x4    /* %ip after SS needs no fixup */
#define UPFIX_RETURN  0x8    /* need to adjust return address on stack */

#ifdef CONFIG_X86_64
struct uprobe_probept_arch_info {
    unsigned long flags;
    unsigned long rip_target_address;
};

struct uprobe_task_arch_info {
    unsigned long saved_scratch_register;
};
#else
struct uprobe_probept_arch_info {
    unsigned long flags;
};

struct uprobe_task_arch_info {};
#endif

struct uprobe_probept;
struct uprobe_task;

static int arch_validate_probed_insn(struct uprobe_probept *ppt,
                        struct task_struct *tsk);

/* On x86, the int3 traps leaves ip pointing past the int3 instruction. */
static inline unsigned long arch_get_probept(struct pt_regs *regs)
{
    return (unsigned long) (regs->ip - BP_INSN_SIZE);
}

static inline void arch_reset_ip_for_sstep(struct pt_regs *regs)
{
    regs->ip -= BP_INSN_SIZE;
}

static inline void arch_restore_uret_addr(unsigned long ret_addr,
    struct pt_regs *regs)
{
    regs->ip = ret_addr;
}

static inline unsigned long arch_get_cur_sp(struct pt_regs *regs)
{
    return (unsigned long) regs->sp;
}

/*
* On x86_32, if a function returns a struct or union, the return
* value is copied into an area created by the caller.  The address
* of this area is passed on the stack as a "hidden" first argument.
* When such a function returns, it uses a "ret $4" instruction to pop
* not only the return address but also the hidden arg.  To accommodate
* such functions, we add 4 bytes of slop when predicting the return
* address. See PR #10078.
*/
#define STRUCT_RETURN_SLOP 4

static inline unsigned long arch_predict_sp_at_ret(struct pt_regs *regs,
        struct task_struct *tsk)
{
    if (test_tsk_thread_flag(tsk, TIF_IA32))
        return (unsigned long) (regs->sp + 4 + STRUCT_RETURN_SLOP);
    else
        return (unsigned long) (regs->sp + 8);
}

static unsigned long arch_hijack_uret_addr(unsigned long trampoline_addr,
                struct pt_regs*, struct uprobe_task*);
#endif                /* _ASM_UPROBES_H */