Merge remote-tracking branch 'bonzini/nbd-for-anthony' into staging

* bonzini/nbd-for-anthony: (26 commits)
  nbd: add myself as maintainer
  qemu-nbd: throttle requests
  qemu-nbd: asynchronous operation
  qemu-nbd: add client pointer to NBDRequest
  qemu-nbd: move client handling to nbd.c
  qemu-nbd: use common main loop
  link the main loop and its dependencies into the tools
  qemu-nbd: introduce NBDRequest
  qemu-nbd: introduce NBDExport
  qemu-nbd: introduce nbd_do_receive_request
  qemu-nbd: more robust handling of invalid requests
  qemu-nbd: introduce nbd_do_send_reply
  qemu-nbd: simplify nbd_trip
  move corking functions to osdep.c
  qemu-nbd: remove data_size argument to nbd_trip
  qemu-nbd: remove offset argument to nbd_trip
  Update ioctl order in nbd_init() to detect EBUSY
  nbd: add support for NBD_CMD_TRIM
  nbd: add support for NBD_CMD_FLUSH
  nbd: add support for NBD_CMD_FLAG_FUA
  ...

1 files changed, 43 insertions, 0 deletions

diff --git a/oslib-posix.c b/oslib-posix.c
index ce755496b5..b6a3c7fc55 100644
--- a/oslib-posix.c
+++ b/oslib-posix.c
@@ -55,6 +55,21 @@ static int running_on_valgrind = -1;
 #else
 #  define running_on_valgrind 0
 #endif
+#ifdef CONFIG_LINUX
+#include <sys/syscall.h>
+#endif
+#ifdef CONFIG_EVENTFD
+#include <sys/eventfd.h>
+#endif
+
+int qemu_get_thread_id(void)
+{
+#if defined(__linux__)
+    return syscall(SYS_gettid);
+#else
+    return getpid();
+#endif
+}
 
 int qemu_daemon(int nochdir, int noclose)
 {
@@ -162,6 +177,34 @@ int qemu_pipe(int pipefd[2])
     return ret;
 }
 
+/*
+ * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
+ */
+int qemu_eventfd(int fds[2])
+{
+#ifdef CONFIG_EVENTFD
+    int ret;
+
+    ret = eventfd(0, 0);
+    if (ret >= 0) {
+        fds[0] = ret;
+        fds[1] = dup(ret);
+        if (fds[1] == -1) {
+            close(ret);
+            return -1;
+        }
+        qemu_set_cloexec(ret);
+        qemu_set_cloexec(fds[1]);
+        return 0;
+    }
+    if (errno != ENOSYS) {
+        return -1;
+    }
+#endif
+
+    return qemu_pipe(fds);
+}
+
 int qemu_utimens(const char *path, const struct timespec *times)
 {
     struct timeval tv[2], tv_now;