Hi, Riku,
Thanks a lots for your review.
I have no problem deleting "#ifdef TARGET_NR_adjtimex" in strace.c.
However, I want to bring to your attention the case of future target Linux
platforms seizing supporting adjtimex(). Let's say this reflects in such a way
that TARGET_NR_adjtimex is not defined for such platform. Then we will have a
compiler error that print_adjtimex() is unused. With "ifdef", we wouldn't.
Thanks,
Aleksandar
________________________________________
From: Riku Voipio [riku.voi...@iki.fi]
Sent: Wednesday, September 21, 2016 9:42 PM
To: Aleksandar Markovic
Cc: qemu-devel@nongnu.org; peter.mayd...@linaro.org; Petar Jovanovic; Miodrag
Dinic; Aleksandar Rikalo; Aleksandar Markovic
Subject: Re: [Qemu-devel] [PATCH v5 1/8] linux-user: Add support for adjtimex()
syscall
On Wed, Sep 14, 2016 at 10:19:54PM +0200, Aleksandar Markovic wrote:
> From: Aleksandar Markovic <aleksandar.marko...@imgtec.com>
>
> This patch implements Qemu user mode adjtimex() syscall support.
>
> Syscall adjtimex() reads and optionally sets parameters for a clock
> adjustment algorithm used in network synchonization or similar scenarios.
>
> The implementation is based on invocation of host's adjtimex(), and
> its key part is in the correspondent case segment of the main switch
> statement of the function do_syscall(), in file linux-user/syscalls.c.
> Also, support for related structure "timex" is added to the file
> linux-user/syscall_defs.h, based on its definition in Linux kernel. All
> necessary conversions of the data structures from target to host and from
> host to target are covered. Two new functions, target_to_host_timex() and
> host_to_target_timex(), are provided for the purpose of such conversions.
> Moreover, the relevant support for "-strace" Qemu option is included in
> files linux-user/strace.c and linux-user/strace.list.
>
> This patch also fixes failures of LTP tests adjtimex01 and adjtimex02, if
> executed in Qemu user mode.
>
> Signed-off-by: Aleksandar Rikalo <aleksandar.rik...@imgtec.com>
> Signed-off-by: Aleksandar Markovic <aleksandar.marko...@imgtec.com>
> ---
> linux-user/strace.c | 12 +++++++
> linux-user/strace.list | 2 +-
> linux-user/syscall.c | 90
> ++++++++++++++++++++++++++++++++++++++++++++++-
> linux-user/syscall_defs.h | 28 +++++++++++++++
> 4 files changed, 130 insertions(+), 2 deletions(-)
>
> diff --git a/linux-user/strace.c b/linux-user/strace.c
> index cc10dc4..7ddcaf8 100644
> --- a/linux-user/strace.c
> +++ b/linux-user/strace.c
> @@ -919,6 +919,18 @@ print_access(const struct syscallname *name,
> }
> #endif
>
> +#ifdef TARGET_NR_adjtimex
The ifdef isn't needed, all linux platorms support adjtimex.
> +static void
> +print_adjtimex(const struct syscallname *name,
> + abi_long arg0, abi_long arg1, abi_long arg2,
> + abi_long arg3, abi_long arg4, abi_long arg5)
> +{
> + print_syscall_prologue(name);
> + print_pointer(arg0, 1);
> + print_syscall_epilogue(name);
> +}
> +#endif
> +
> #ifdef TARGET_NR_brk
> static void
> print_brk(const struct syscallname *name,
> diff --git a/linux-user/strace.list b/linux-user/strace.list
> index aa967a2..9a665a8 100644
> --- a/linux-user/strace.list
> +++ b/linux-user/strace.list
> @@ -16,7 +16,7 @@
> { TARGET_NR_add_key, "add_key" , NULL, NULL, NULL },
> #endif
> #ifdef TARGET_NR_adjtimex
> -{ TARGET_NR_adjtimex, "adjtimex" , NULL, NULL, NULL },
> +{ TARGET_NR_adjtimex, "adjtimex" , NULL, print_adjtimex, NULL },
> #endif
> #ifdef TARGET_NR_afs_syscall
> { TARGET_NR_afs_syscall, "afs_syscall" , NULL, NULL, NULL },
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index ca06943..5643840 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -35,6 +35,7 @@
> #include <sys/swap.h>
> #include <linux/capability.h>
> #include <sched.h>
> +#include <sys/timex.h>
> #ifdef __ia64__
> int __clone2(int (*fn)(void *), void *child_stack_base,
> size_t stack_size, int flags, void *arg, ...);
> @@ -6578,6 +6579,78 @@ static inline abi_long target_ftruncate64(void
> *cpu_env, abi_long arg1,
> }
> #endif
>
> +#ifdef TARGET_NR_adjtimex
> +static inline abi_long target_to_host_timex(struct timex *host_buf,
> + abi_long target_addr)
> +{
> + struct target_timex *target_buf;
> +
> + if (!lock_user_struct(VERIFY_READ, target_buf, target_addr, 1)) {
> + return -TARGET_EFAULT;
> + }
> +
> + host_buf->modes = tswap32(target_buf->modes);
> + host_buf->offset = tswapal(target_buf->offset);
> + host_buf->freq = tswapal(target_buf->freq);
> + host_buf->maxerror = tswapal(target_buf->maxerror);
> + host_buf->esterror = tswapal(target_buf->esterror);
> + host_buf->status = tswap32(target_buf->status);
> + host_buf->constant = tswapal(target_buf->constant);
> + host_buf->precision = tswapal(target_buf->precision);
> + host_buf->tolerance = tswapal(target_buf->tolerance);
> + host_buf->time.tv_sec = tswapal(target_buf->time.tv_sec);
> + host_buf->time.tv_usec = tswapal(target_buf->time.tv_usec);
> + host_buf->tick = tswapal(target_buf->tick);
> + host_buf->ppsfreq = tswapal(target_buf->ppsfreq);
> + host_buf->jitter = tswapal(target_buf->jitter);
> + host_buf->shift = tswap32(target_buf->shift);
> + host_buf->stabil = tswapal(target_buf->stabil);
> + host_buf->jitcnt = tswapal(target_buf->jitcnt);
> + host_buf->calcnt = tswapal(target_buf->calcnt);
> + host_buf->errcnt = tswapal(target_buf->errcnt);
> + host_buf->stbcnt = tswapal(target_buf->stbcnt);
> + host_buf->tai = tswap32(target_buf->tai);
> +
> + unlock_user_struct(target_buf, target_addr, 0);
> + return 0;
> +}
> +
> +static inline abi_long host_to_target_timex(abi_long target_addr,
> + struct timex *host_buf)
> +{
> + struct target_timex *target_buf;
> +
> + if (!lock_user_struct(VERIFY_WRITE, target_buf, target_addr, 0)) {
> + return -TARGET_EFAULT;
> + }
> +
> + target_buf->modes = tswap32(host_buf->modes);
> + target_buf->offset = tswapal(host_buf->offset);
> + target_buf->freq = tswapal(host_buf->freq);
> + target_buf->maxerror = tswapal(host_buf->maxerror);
> + target_buf->esterror = tswapal(host_buf->esterror);
> + target_buf->status = tswap32(host_buf->status);
> + target_buf->constant = tswapal(host_buf->constant);
> + target_buf->precision = tswapal(host_buf->precision);
> + target_buf->tolerance = tswapal(host_buf->tolerance);
> + target_buf->time.tv_sec = tswapal(host_buf->time.tv_sec);
> + target_buf->time.tv_usec = tswapal(host_buf->time.tv_usec);
> + target_buf->tick = tswapal(host_buf->tick);
> + target_buf->ppsfreq = tswapal(host_buf->ppsfreq);
> + target_buf->jitter = tswapal(host_buf->jitter);
> + target_buf->shift = tswap32(host_buf->shift);
> + target_buf->stabil = tswapal(host_buf->stabil);
> + target_buf->jitcnt = tswapal(host_buf->jitcnt);
> + target_buf->calcnt = tswapal(host_buf->calcnt);
> + target_buf->errcnt = tswapal(host_buf->errcnt);
> + target_buf->stbcnt = tswapal(host_buf->stbcnt);
> + target_buf->tai = tswap32(host_buf->tai);
> +
> + unlock_user_struct(target_buf, target_addr, 1);
> + return 0;
> +}
> +#endif
> +
> static inline abi_long target_to_host_timespec(struct timespec *host_ts,
> abi_ulong target_addr)
> {
> @@ -9419,8 +9492,23 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> break;
> #endif
> #endif
> +#ifdef TARGET_NR_adjtimex
> case TARGET_NR_adjtimex:
> - goto unimplemented;
> + {
> + struct timex host_buf;
> +
> + if (target_to_host_timex(&host_buf, arg1) != 0) {
> + goto efault;
> + }
> + ret = get_errno(adjtimex(&host_buf));
> + if (!is_error(ret) && arg1) {
> + if (host_to_target_timex(arg1, &host_buf) != 0) {
> + goto efault;
> + }
> + }
> + }
> + break;
> +#endif
> #ifdef TARGET_NR_create_module
> case TARGET_NR_create_module:
> #endif
> diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
> index 7835654..afd9191 100644
> --- a/linux-user/syscall_defs.h
> +++ b/linux-user/syscall_defs.h
> @@ -207,6 +207,34 @@ struct target_itimerspec {
> struct target_timespec it_value;
> };
>
> +struct target_timex {
> + unsigned int modes; /* Mode selector */
> + abi_long offset; /* Time offset */
> + abi_long freq; /* Frequency offset */
> + abi_long maxerror; /* Maximum error (microseconds) */
> + abi_long esterror; /* Estimated error (microseconds) */
> + int status; /* Clock command/status */
> + abi_long constant; /* PLL (phase-locked loop) time constant */
> + abi_long precision; /* Clock precision (microseconds, ro) */
> + abi_long tolerance; /* Clock freq. tolerance (ppm, ro) */
> + struct target_timeval time; /* Current time */
> + abi_long tick; /* Microseconds between clock ticks */
> + abi_long ppsfreq; /* PPS (pulse per second) frequency */
> + abi_long jitter; /* PPS jitter (ro); nanoseconds */
> + int shift; /* PPS interval duration (seconds) */
> + abi_long stabil; /* PPS stability */
> + abi_long jitcnt; /* PPS jitter limit exceeded (ro) */
> + abi_long calcnt; /* PPS calibration intervals */
> + abi_long errcnt; /* PPS calibration errors */
> + abi_long stbcnt; /* PPS stability limit exceeded */
> + int tai; /* TAI offset */
> +
> + /* Further padding bytes to allow for future expansion */
> + int:32; int:32; int:32; int:32;
> + int:32; int:32; int:32; int:32;
> + int:32; int:32; int:32;
> +};
> +
> typedef abi_long target_clock_t;
>
> #define TARGET_HZ 100
> --
> 2.9.3
>
>
