[PATCH v2 2/2] linux-user: Add support for utimensat_time64() and semtimedop_time64()

[Filip Bozuta <Filip.Bozuta@syrmia.com>]

This patch introduces functionality for following time64 syscalls:

*utimensat_time64()

    int utimensat(int dirfd, const char *pathname,
                  const struct timespec times[2], int flags);
    -- change file timestamps with nanosecond precision --
    man page: https://man7.org/linux/man-pages/man2/utimensat.2.html

*semtimedop_time64()

    int semtimedop(int semid, struct sembuf *sops, size_t nsops,
                   const struct timespec *timeout);
    -- System V semaphore operations --
    man page: https://www.man7.org/linux/man-pages/man2/semtimedop.2.html

Implementation notes:

   Syscall 'utimensat_time64()' is implemented in similar way as its
   regular variants only difference being that time64 converting function
   is used to convert values of 'struct timespec' between host and target
   ('target_to_host_timespec64()').

   For syscall 'semtimedop_time64()' and additional argument is added
   in function 'do_semtimedop()' through which the aproppriate 'struct timespec'
   converting function is called (false for regular target_to_host_timespec()
   and true for target_to_host_timespec64()). For 'do_ipc()' a
   check was added as that additional argument: 'TARGET_ABI_BITS == 64'.

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c | 60 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 50 insertions(+), 10 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index fc6a6e32e4..4d460af744 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1253,7 +1253,8 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
 #endif
 
 #if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64) || \
-    defined(TARGET_NR_pselect6_time64) || defined(TARGET_NR_ppoll_time64)
+    defined(TARGET_NR_pselect6_time64) || defined(TARGET_NR_ppoll_time64) || \
+    defined(TARGET_NR_utimensat_time64) || defined(TARGET_NR_semtimedop_time64)
 static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
                                                  abi_ulong target_addr)
 {
@@ -4117,7 +4118,7 @@ static inline abi_long target_to_host_sembuf(struct sembuf *host_sembuf,
 }
 
 #if defined(TARGET_NR_ipc) || defined(TARGET_NR_semop) || \
-    defined(TARGET_NR_semtimedop)
+    defined(TARGET_NR_semtimedop) || defined(TARGET_NR_semtimedop_time64)
 
 /*
  * This macro is required to handle the s390 variants, which passes the
@@ -4134,7 +4135,7 @@ static inline abi_long target_to_host_sembuf(struct sembuf *host_sembuf,
 static inline abi_long do_semtimedop(int semid,
                                      abi_long ptr,
                                      unsigned nsops,
-                                     abi_long timeout)
+                                     abi_long timeout, bool time64)
 {
     struct sembuf sops[nsops];
     struct timespec ts, *pts = NULL;
@@ -4142,8 +4143,14 @@ static inline abi_long do_semtimedop(int semid,
 
     if (timeout) {
         pts = &ts;
-        if (target_to_host_timespec(pts, timeout)) {
-            return -TARGET_EFAULT;
+        if (time64) {
+            if (target_to_host_timespec64(pts, timeout)) {
+                return -TARGET_EFAULT;
+            }
+        } else {
+            if (target_to_host_timespec(pts, timeout)) {
+                return -TARGET_EFAULT;
+            }
         }
     }
 
@@ -4657,7 +4664,7 @@ static abi_long do_ipc(CPUArchState *cpu_env,
 
     switch (call) {
     case IPCOP_semop:
-        ret = do_semtimedop(first, ptr, second, 0);
+        ret = do_semtimedop(first, ptr, second, 0, false);
         break;
     case IPCOP_semtimedop:
     /*
@@ -4667,9 +4674,9 @@ static abi_long do_ipc(CPUArchState *cpu_env,
      * to a struct timespec where the generic variant uses fifth parameter.
      */
 #if defined(TARGET_S390X)
-        ret = do_semtimedop(first, ptr, second, third);
+        ret = do_semtimedop(first, ptr, second, third, TARGET_ABI_BITS == 64);
 #else
-        ret = do_semtimedop(first, ptr, second, fifth);
+        ret = do_semtimedop(first, ptr, second, fifth, TARGET_ABI_BITS == 64);
 #endif
         break;
 
@@ -9887,11 +9894,15 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
 #endif
 #ifdef TARGET_NR_semop
     case TARGET_NR_semop:
-        return do_semtimedop(arg1, arg2, arg3, 0);
+        return do_semtimedop(arg1, arg2, arg3, 0, false);
 #endif
 #ifdef TARGET_NR_semtimedop
     case TARGET_NR_semtimedop:
-        return do_semtimedop(arg1, arg2, arg3, arg4);
+        return do_semtimedop(arg1, arg2, arg3, arg4, false);
+#endif
+#ifdef TARGET_NR_semtimedop_time64
+    case TARGET_NR_semtimedop_time64:
+        return do_semtimedop(arg1, arg2, arg3, arg4, true);
 #endif
 #ifdef TARGET_NR_semctl
     case TARGET_NR_semctl:
@@ -11938,6 +11949,35 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         }
         return ret;
 #endif
+#ifdef TARGET_NR_utimensat_time64
+    case TARGET_NR_utimensat_time64:
+        {
+            struct timespec *tsp, ts[2];
+            if (!arg3) {
+                tsp = NULL;
+            } else {
+                if (target_to_host_timespec64(ts, arg3)) {
+                    return -TARGET_EFAULT;
+                }
+                if (target_to_host_timespec64(ts + 1, arg3 +
+                                     sizeof(struct target__kernel_timespec))) {
+                    return -TARGET_EFAULT;
+                }
+                tsp = ts;
+            }
+            if (!arg2)
+                ret = get_errno(sys_utimensat(arg1, NULL, tsp, arg4));
+            else {
+                p = lock_user_string(arg2);
+                if (!p) {
+                    return -TARGET_EFAULT;
+                }
+                ret = get_errno(sys_utimensat(arg1, path(p), tsp, arg4));
+                unlock_user(p, arg2, 0);
+            }
+        }
+        return ret;
+#endif
 #ifdef TARGET_NR_futex
     case TARGET_NR_futex:
         return do_futex(arg1, arg2, arg3, arg4, arg5, arg6);
-- 
2.25.1