linux-user: support timerfd_{create, gettime, settime} syscalls

Adds support for the timerfd_create, timerfd_gettime & timerfd_settime
syscalls, allowing use of timerfds by target programs.

v2: By Riku - added configure check for timerfd and ifdefs
for benefit of old distributions like RHEL5.

Signed-off-by: Paul Burton <paul@archlinuxmips.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

3 files changed, 71 insertions, 0 deletions

diff --git a/configure b/configure
index 283c71cb7a..3d0ab1b193 100755
--- a/configure
+++ b/configure
@@ -3456,6 +3456,20 @@ if compile_prog "" "" ; then
   sendfile=yes
 fi
 
+# check for timerfd support (glibc 2.8 and newer)
+timerfd=no
+cat > $TMPC << EOF
+#include <sys/timerfd.h>
+
+int main(void)
+{
+    return(timerfd_create(CLOCK_REALTIME, 0));
+}
+EOF
+if compile_prog "" "" ; then
+  timerfd=yes
+fi
+
 # Check if tools are available to build documentation.
 if test "$docs" != "no" ; then
   if has makeinfo && has pod2man; then
@@ -4524,6 +4538,9 @@ fi
 if test "$sendfile" = "yes" ; then
   echo "CONFIG_SENDFILE=y" >> $config_host_mak
 fi
+if test "$timerfd" = "yes" ; then
+  echo "CONFIG_TIMERFD=y" >> $config_host_mak
+fi
 if test "$inotify" = "yes" ; then
   echo "CONFIG_INOTIFY=y" >> $config_host_mak
 fi
diff --git a/linux-user/strace.list b/linux-user/strace.list
index fcb258d348..8de972a6ee 100644
--- a/linux-user/strace.list
+++ b/linux-user/strace.list
@@ -1404,6 +1404,15 @@
 #ifdef TARGET_NR_timer_settime
 { TARGET_NR_timer_settime, "timer_settime" , NULL, NULL, NULL },
 #endif
+#ifdef TARGET_NR_timerfd_create
+{ TARGET_NR_timerfd_create, "timerfd_create" , NULL, NULL, NULL },
+#endif
+#ifdef TARGET_NR_timerfd_gettime
+{ TARGET_NR_timerfd_gettime, "timerfd_gettime" , NULL, NULL, NULL },
+#endif
+#ifdef TARGET_NR_timerfd_settime
+{ TARGET_NR_timerfd_settime, "timerfd_settime" , NULL, NULL, NULL },
+#endif
 #ifdef TARGET_NR_times
 { TARGET_NR_times, "times" , NULL, NULL, NULL },
 #endif
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 7c108abcf2..44853d090a 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -58,6 +58,7 @@ int __clone2(int (*fn)(void *), void *child_stack_base,
 #include <sys/shm.h>
 #include <sys/sem.h>
 #include <sys/statfs.h>
+#include <sys/timerfd.h>
 #include <utime.h>
 #include <sys/sysinfo.h>
 //#include <sys/user.h>
@@ -9547,6 +9548,50 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
     }
 #endif
 
+#if defined(TARGET_NR_timerfd_create) && defined(CONFIG_TIMERFD)
+    case TARGET_NR_timerfd_create:
+        ret = get_errno(timerfd_create(arg1,
+                target_to_host_bitmask(arg2, fcntl_flags_tbl)));
+        break;
+#endif
+
+#if defined(TARGET_NR_timerfd_gettime) && defined(CONFIG_TIMERFD)
+    case TARGET_NR_timerfd_gettime:
+        {
+            struct itimerspec its_curr;
+
+            ret = get_errno(timerfd_gettime(arg1, &its_curr));
+
+            if (arg2 && host_to_target_itimerspec(arg2, &its_curr)) {
+                goto efault;
+            }
+        }
+        break;
+#endif
+
+#if defined(TARGET_NR_timerfd_settime) && defined(CONFIG_TIMERFD)
+    case TARGET_NR_timerfd_settime:
+        {
+            struct itimerspec its_new, its_old, *p_new;
+
+            if (arg3) {
+                if (target_to_host_itimerspec(&its_new, arg3)) {
+                    goto efault;
+                }
+                p_new = &its_new;
+            } else {
+                p_new = NULL;
+            }
+
+            ret = get_errno(timerfd_settime(arg1, arg2, p_new, &its_old));
+
+            if (arg4 && host_to_target_itimerspec(arg4, &its_old)) {
+                goto efault;
+            }
+        }
+        break;
+#endif
+
     default:
     unimplemented:
         gemu_log("qemu: Unsupported syscall: %d\n", num);