qemu/linux-user/riscv/target_syscall.h
Filip Bozuta 02e5d7d78e linux-user: Add strace support for printing arguments of syscalls used to lock and unlock memory
This patch implements strace argument printing functionality for following syscalls:

    * mlock, munlock, mlockall, munlockall - lock and unlock memory

       int mlock(const void *addr, size_t len)
       int munlock(const void *addr, size_t len)
       int mlockall(int flags)
       int munlockall(void)
       man page: https://man7.org/linux/man-pages/man2/mlock.2.html

Implementation notes:

    Syscall mlockall() takes an argument that is composed of predefined values
    which represent flags that determine the type of locking operation that is
    to be performed. For that reason, a printing function "print_mlockall" was
    stated in file "strace.list". This printing function uses an already existing
    function "print_flags()" to print the "flags" argument.  These flags are stated
    inside an array "mlockall_flags" that contains values of type "struct flags".
    These values are instantiated using an existing macro "FLAG_TARGET()" that
    crates aproppriate target flag values based on those defined in files
    '/target_syscall.h'. These target flag values were changed from
    "TARGET_MLOCKALL_MCL*" to "TARGET_MCL_*" so that they can be aproppriately set
    and recognised in "strace.c" with "FLAG_TARGET()". Value for "MCL_ONFAULT"
    was added in this patch. This value was also added in "syscall.c" in function
    "target_to_host_mlockall_arg()". Because this flag value was added in kernel
    version 4.4, it is enwrapped in an #ifdef directive (both in "syscall.c" and
    in "strace.c") as to support older kernel versions.
    The other syscalls have only primitive argument types, so the
    rest of the implementation was handled by stating an appropriate
    printing format in file "strace.list". Syscall mlock2() is not implemented in
    "syscall.c" and thus it's argument printing is not implemented in this patch.

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200811164553.27713-4-Filip.Bozuta@syrmia.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-08-27 12:29:50 +02:00

63 lines
1.2 KiB
C

/*
* This struct defines the way the registers are stored on the
* stack during a system call.
*
* Reference: linux/arch/riscv/include/uapi/asm/ptrace.h
*/
#ifndef LINUX_USER_RISCV_TARGET_SYSCALL_H
#define LINUX_USER_RISCV_TARGET_SYSCALL_H
struct target_pt_regs {
abi_long sepc;
abi_long ra;
abi_long sp;
abi_long gp;
abi_long tp;
abi_long t0;
abi_long t1;
abi_long t2;
abi_long s0;
abi_long s1;
abi_long a0;
abi_long a1;
abi_long a2;
abi_long a3;
abi_long a4;
abi_long a5;
abi_long a6;
abi_long a7;
abi_long s2;
abi_long s3;
abi_long s4;
abi_long s5;
abi_long s6;
abi_long s7;
abi_long s8;
abi_long s9;
abi_long s10;
abi_long s11;
abi_long t3;
abi_long t4;
abi_long t5;
abi_long t6;
};
#ifdef TARGET_RISCV32
#define UNAME_MACHINE "riscv32"
#else
#define UNAME_MACHINE "riscv64"
#endif
#define UNAME_MINIMUM_RELEASE "4.15.0"
#define TARGET_MINSIGSTKSZ 2048
#define TARGET_MCL_CURRENT 1
#define TARGET_MCL_FUTURE 2
#define TARGET_MCL_ONFAULT 4
/* clone(flags, newsp, ptidptr, tls, ctidptr) for RISC-V */
/* This comes from linux/kernel/fork.c, CONFIG_CLONE_BACKWARDS */
#define TARGET_CLONE_BACKWARDS
#endif