[PULL 16/18] linux-user: Add support for 'clock_nanosleep_time64()' and 'clock_adjtime64()'

[Laurent Vivier <laurent@vivier.eu>]

From: Filip Bozuta <Filip.Bozuta@syrmia.com>

This patch implements functionality for following time64 syscall:

*clock_nanosleep_time64()

    This is a year 2038 safe vairant of syscall:
    int clock_nanosleep(clockid_t clockid, int flags,
                        const struct timespec *request,
                        struct timespec *remain)
    --high-resolution sleep with specifiable clock--
    man page: https://man7.org/linux/man-pages/man2/clock_nanosleep.2.html

*clock_adjtime64()

    This is a year 2038 safe variant of syscall:
    int clock_adjtime(clockid_t clk_id, struct timex *buf)
    --tune kernel clock--
    man page: https://man7.org/linux/man-pages/man2/clock_adjtime.2.html

Implementation notes:

    Syscall 'clock_nanosleep_time64()' was implemented similarly
    to syscall 'clock_nanosleep()' except that 'host_to_target_timespec64()'
    and 'target_to_host_timespec64()' were used instead of the regular
    'host_to_target_timespec()' and 'target_to_host_timespec()'.

    For 'clock_adjtime64()' a 64-bit target kernel version of 'struct timex'
    was defined in 'syscall_defs.h': 'struct target__kernel_timex'.
    This type was used to convert the values of 64-bit timex type between
    host and target. For this purpose a 64-bit timex converting functions
    'target_to_host_timex64()' and 'host_to_target_timex64()'. An existing
    function 'copy_to_user_timeval64()' was used to convert the field
    'time' which if of type 'struct timeval' from host to target.
    Function 'copy_from_user_timveal64()' was added in this patch and
    used to convert the 'time' field from target to host.

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200824192116.65562-2-Filip.Bozuta@syrmia.com>
[lv: add missing defined(TARGET_NR_clock_nanosleep_time64)]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c      | 140 +++++++++++++++++++++++++++++++++++++-
 linux-user/syscall_defs.h |  31 +++++++++
 2 files changed, 168 insertions(+), 3 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index b28c8edb421e..82414c08d655 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -774,7 +774,8 @@ safe_syscall4(int, accept4, int, fd, struct sockaddr *, addr, socklen_t *, len,
 safe_syscall2(int, nanosleep, const struct timespec *, req,
               struct timespec *, rem)
 #endif
-#ifdef TARGET_NR_clock_nanosleep
+#if defined(TARGET_NR_clock_nanosleep) || \
+    defined(TARGET_NR_clock_nanosleep_time64)
 safe_syscall4(int, clock_nanosleep, const clockid_t, clock, int, flags,
               const struct timespec *, req, struct timespec *, rem)
 #endif
@@ -1177,8 +1178,25 @@ static inline abi_long copy_to_user_timeval(abi_ulong target_tv_addr,
     return 0;
 }
 
+static inline abi_long copy_from_user_timeval64(struct timeval *tv,
+                                                abi_ulong target_tv_addr)
+{
+    struct target__kernel_sock_timeval *target_tv;
+
+    if (!lock_user_struct(VERIFY_READ, target_tv, target_tv_addr, 1)) {
+        return -TARGET_EFAULT;
+    }
+
+    __get_user(tv->tv_sec, &target_tv->tv_sec);
+    __get_user(tv->tv_usec, &target_tv->tv_usec);
+
+    unlock_user_struct(target_tv, target_tv_addr, 0);
+
+    return 0;
+}
+
 static inline abi_long copy_to_user_timeval64(abi_ulong target_tv_addr,
-                                             const struct timeval *tv)
+                                              const struct timeval *tv)
 {
     struct target__kernel_sock_timeval *target_tv;
 
@@ -1222,7 +1240,8 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
     defined(TARGET_NR_timer_settime64) || \
     defined(TARGET_NR_mq_timedsend_time64) || \
     defined(TARGET_NR_mq_timedreceive_time64) || \
-    (defined(TARGET_NR_timerfd_settime64) && defined(CONFIG_TIMERFD))
+    (defined(TARGET_NR_timerfd_settime64) && defined(CONFIG_TIMERFD)) || \
+    defined(TARGET_NR_clock_nanosleep_time64)
 static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
                                                  abi_ulong target_addr)
 {
@@ -6953,6 +6972,87 @@ static inline abi_long host_to_target_timex(abi_long target_addr,
 }
 #endif
 
+
+#if defined(TARGET_NR_clock_adjtime64) && defined(CONFIG_CLOCK_ADJTIME)
+static inline abi_long target_to_host_timex64(struct timex *host_tx,
+                                              abi_long target_addr)
+{
+    struct target__kernel_timex *target_tx;
+
+    if (copy_from_user_timeval64(&host_tx->time, target_addr +
+                                 offsetof(struct target__kernel_timex,
+                                          time))) {
+        return -TARGET_EFAULT;
+    }
+
+    if (!lock_user_struct(VERIFY_READ, target_tx, target_addr, 1)) {
+        return -TARGET_EFAULT;
+    }
+
+    __get_user(host_tx->modes, &target_tx->modes);
+    __get_user(host_tx->offset, &target_tx->offset);
+    __get_user(host_tx->freq, &target_tx->freq);
+    __get_user(host_tx->maxerror, &target_tx->maxerror);
+    __get_user(host_tx->esterror, &target_tx->esterror);
+    __get_user(host_tx->status, &target_tx->status);
+    __get_user(host_tx->constant, &target_tx->constant);
+    __get_user(host_tx->precision, &target_tx->precision);
+    __get_user(host_tx->tolerance, &target_tx->tolerance);
+    __get_user(host_tx->tick, &target_tx->tick);
+    __get_user(host_tx->ppsfreq, &target_tx->ppsfreq);
+    __get_user(host_tx->jitter, &target_tx->jitter);
+    __get_user(host_tx->shift, &target_tx->shift);
+    __get_user(host_tx->stabil, &target_tx->stabil);
+    __get_user(host_tx->jitcnt, &target_tx->jitcnt);
+    __get_user(host_tx->calcnt, &target_tx->calcnt);
+    __get_user(host_tx->errcnt, &target_tx->errcnt);
+    __get_user(host_tx->stbcnt, &target_tx->stbcnt);
+    __get_user(host_tx->tai, &target_tx->tai);
+
+    unlock_user_struct(target_tx, target_addr, 0);
+    return 0;
+}
+
+static inline abi_long host_to_target_timex64(abi_long target_addr,
+                                              struct timex *host_tx)
+{
+    struct target__kernel_timex *target_tx;
+
+   if (copy_to_user_timeval64(target_addr +
+                              offsetof(struct target__kernel_timex, time),
+                              &host_tx->time)) {
+        return -TARGET_EFAULT;
+    }
+
+    if (!lock_user_struct(VERIFY_WRITE, target_tx, target_addr, 0)) {
+        return -TARGET_EFAULT;
+    }
+
+    __put_user(host_tx->modes, &target_tx->modes);
+    __put_user(host_tx->offset, &target_tx->offset);
+    __put_user(host_tx->freq, &target_tx->freq);
+    __put_user(host_tx->maxerror, &target_tx->maxerror);
+    __put_user(host_tx->esterror, &target_tx->esterror);
+    __put_user(host_tx->status, &target_tx->status);
+    __put_user(host_tx->constant, &target_tx->constant);
+    __put_user(host_tx->precision, &target_tx->precision);
+    __put_user(host_tx->tolerance, &target_tx->tolerance);
+    __put_user(host_tx->tick, &target_tx->tick);
+    __put_user(host_tx->ppsfreq, &target_tx->ppsfreq);
+    __put_user(host_tx->jitter, &target_tx->jitter);
+    __put_user(host_tx->shift, &target_tx->shift);
+    __put_user(host_tx->stabil, &target_tx->stabil);
+    __put_user(host_tx->jitcnt, &target_tx->jitcnt);
+    __put_user(host_tx->calcnt, &target_tx->calcnt);
+    __put_user(host_tx->errcnt, &target_tx->errcnt);
+    __put_user(host_tx->stbcnt, &target_tx->stbcnt);
+    __put_user(host_tx->tai, &target_tx->tai);
+
+    unlock_user_struct(target_tx, target_addr, 1);
+    return 0;
+}
+#endif
+
 static inline abi_long target_to_host_sigevent(struct sigevent *host_sevp,
                                                abi_ulong target_addr)
 {
@@ -9940,6 +10040,21 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
             }
         }
         return ret;
+#endif
+#if defined(TARGET_NR_clock_adjtime64) && defined(CONFIG_CLOCK_ADJTIME)
+    case TARGET_NR_clock_adjtime64:
+        {
+            struct timex htx;
+
+            if (target_to_host_timex64(&htx, arg2) != 0) {
+                return -TARGET_EFAULT;
+            }
+            ret = get_errno(clock_adjtime(arg1, &htx));
+            if (!is_error(ret) && host_to_target_timex64(arg2, &htx)) {
+                    return -TARGET_EFAULT;
+            }
+        }
+        return ret;
 #endif
     case TARGET_NR_getpgid:
         return get_errno(getpgid(arg1));
@@ -11911,6 +12026,25 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         return ret;
     }
 #endif
+#ifdef TARGET_NR_clock_nanosleep_time64
+    case TARGET_NR_clock_nanosleep_time64:
+    {
+        struct timespec ts;
+
+        if (target_to_host_timespec64(&ts, arg3)) {
+            return -TARGET_EFAULT;
+        }
+
+        ret = get_errno(safe_clock_nanosleep(arg1, arg2,
+                                             &ts, arg4 ? &ts : NULL));
+
+        if (ret == -TARGET_EINTR && arg4 && arg2 != TIMER_ABSTIME &&
+            host_to_target_timespec64(arg4, &ts)) {
+            return -TARGET_EFAULT;
+        }
+        return ret;
+    }
+#endif
 
 #if defined(TARGET_NR_set_tid_address) && defined(__NR_set_tid_address)
     case TARGET_NR_set_tid_address:
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index a6abc7e70be8..9d07991176b8 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -294,6 +294,37 @@ struct target_timex {
     abi_int:32; abi_int:32; abi_int:32;
 };
 
+struct target__kernel_timex {
+    abi_uint modes;               /* Mode selector */
+    abi_int: 32;                  /* pad */
+    abi_llong offset;             /* Time offset */
+    abi_llong freq;               /* Frequency offset */
+    abi_llong maxerror;           /* Maximum error (microseconds) */
+    abi_llong esterror;           /* Estimated error (microseconds) */
+    abi_int status;               /* Clock command/status */
+    abi_int: 32;                  /* pad */
+    abi_llong constant;           /* PLL (phase-locked loop) time constant */
+    abi_llong precision;          /* Clock precision (microseconds, ro) */
+    abi_llong tolerance;          /* Clock freq. tolerance (ppm, ro) */
+    struct target__kernel_sock_timeval time;  /* Current time */
+    abi_llong tick;               /* Microseconds between clock ticks */
+    abi_llong ppsfreq;            /* PPS (pulse per second) frequency */
+    abi_llong jitter;             /* PPS jitter (ro); nanoseconds */
+    abi_int shift;                /* PPS interval duration (seconds) */
+    abi_int: 32;                  /* pad */
+    abi_llong stabil;             /* PPS stability */
+    abi_llong jitcnt;             /* PPS jitter limit exceeded (ro) */
+    abi_llong calcnt;             /* PPS calibration intervals */
+    abi_llong errcnt;             /* PPS calibration errors */
+    abi_llong stbcnt;             /* PPS stability limit exceeded */
+    abi_int tai;                  /* TAI offset */
+
+    /* Further padding bytes to allow for future expansion */
+    abi_int:32; abi_int:32; abi_int:32; abi_int:32;
+    abi_int:32; abi_int:32; abi_int:32; abi_int:32;
+    abi_int:32; abi_int:32; abi_int:32;
+};
+
 typedef abi_long target_clock_t;
 
 #define TARGET_HZ 100
-- 
2.26.2