qemu-patch-raspberry4/linux-user/sparc/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

45 lines
1.2 KiB
C

#ifndef SPARC_TARGET_SYSCALL_H
#define SPARC_TARGET_SYSCALL_H
#include "target_errno.h"
struct target_pt_regs {
abi_ulong psr;
abi_ulong pc;
abi_ulong npc;
abi_ulong y;
abi_ulong u_regs[16];
};
#define UNAME_MACHINE "sparc"
#define UNAME_MINIMUM_RELEASE "2.6.32"
/* SPARC kernels don't define this in their Kconfig, but they have the
* same ABI as if they did, implemented by sparc-specific code which fishes
* directly in the u_regs() struct for half the parameters in sparc_do_fork()
* and copy_thread().
*/
#define TARGET_CLONE_BACKWARDS
#define TARGET_MINSIGSTKSZ 4096
#define TARGET_MCL_CURRENT 0x2000
#define TARGET_MCL_FUTURE 0x4000
#define TARGET_MCL_ONFAULT 0x8000
/* For SPARC SHMLBA is determined at runtime in the kernel, and
* libc has to runtime-detect it using the hwcaps (see glibc
* sysdeps/unix/sysv/linux/sparc/getshmlba; we follow the same
* logic here, though we know we're not the sparc v9 64-bit case).
*/
#define TARGET_FORCE_SHMLBA
static inline abi_ulong target_shmlba(CPUSPARCState *env)
{
if (!(env->def.features & CPU_FEATURE_FLUSH)) {
return 64 * 1024;
} else {
return 256 * 1024;
}
}
#endif /* SPARC_TARGET_SYSCALL_H */