qemu/linux-user/cris/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

48 lines
1.3 KiB
C

#ifndef CRIS_TARGET_SYSCALL_H
#define CRIS_TARGET_SYSCALL_H
#define UNAME_MACHINE "cris"
#define UNAME_MINIMUM_RELEASE "2.6.32"
/* pt_regs not only specifices the format in the user-struct during
* ptrace but is also the frame format used in the kernel prologue/epilogues
* themselves
*/
struct target_pt_regs {
unsigned long orig_r10;
/* pushed by movem r13, [sp] in SAVE_ALL. */
unsigned long r0;
unsigned long r1;
unsigned long r2;
unsigned long r3;
unsigned long r4;
unsigned long r5;
unsigned long r6;
unsigned long r7;
unsigned long r8;
unsigned long r9;
unsigned long r10;
unsigned long r11;
unsigned long r12;
unsigned long r13;
unsigned long acr;
unsigned long srs;
unsigned long mof;
unsigned long spc;
unsigned long ccs;
unsigned long srp;
unsigned long erp; /* This is actually the debugged process' PC */
/* For debugging purposes; saved only when needed. */
unsigned long exs;
unsigned long eda;
};
#define TARGET_CLONE_BACKWARDS2
#define TARGET_MINSIGSTKSZ 2048
#define TARGET_MCL_CURRENT 1
#define TARGET_MCL_FUTURE 2
#define TARGET_MCL_ONFAULT 4
#endif