Merge remote-tracking branch 'remotes/mdroth/tags/qga-pull-2017-03-06-tag' into staging

qemu-ga patch queue for 2.9

* fix fsfreeze for filesystems mounted in multiple locations
* fix test failure when running in a chroot
* support for socket-based activation

# gpg: Signature made Mon 06 Mar 2017 07:54:17 GMT
# gpg:                using RSA key 0x3353C9CEF108B584
# gpg: Good signature from "Michael Roth <flukshun@gmail.com>"
# gpg:                 aka "Michael Roth <mdroth@utexas.edu>"
# gpg:                 aka "Michael Roth <mdroth@linux.vnet.ibm.com>"
# Primary key fingerprint: CEAC C9E1 5534 EBAB B82D  3FA0 3353 C9CE F108 B584

* remotes/mdroth/tags/qga-pull-2017-03-06-tag:
  tests: check path to avoid a failing qga/get-vcpus test
  qga: ignore EBUSY when freezing a filesystem
  qga: add systemd socket activation support

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

5 files changed, 114 insertions, 38 deletions

diff --git a/qga/channel-posix.c b/qga/channel-posix.c
index 71582e0c38..3f34465159 100644
--- a/qga/channel-posix.c
+++ b/qga/channel-posix.c
@@ -118,14 +118,16 @@ static int ga_channel_client_add(GAChannel *c, int fd)
     return 0;
 }
 
-static gboolean ga_channel_open(GAChannel *c, const gchar *path, GAChannelMethod method)
+static gboolean ga_channel_open(GAChannel *c, const gchar *path,
+                                GAChannelMethod method, int fd)
 {
     int ret;
     c->method = method;
 
     switch (c->method) {
     case GA_CHANNEL_VIRTIO_SERIAL: {
-        int fd = qemu_open(path, O_RDWR | O_NONBLOCK
+        assert(fd < 0);
+        fd = qemu_open(path, O_RDWR | O_NONBLOCK
 #ifndef CONFIG_SOLARIS
                            | O_ASYNC
 #endif
@@ -153,7 +155,9 @@ static gboolean ga_channel_open(GAChannel *c, const gchar *path, GAChannelMethod
     }
     case GA_CHANNEL_ISA_SERIAL: {
         struct termios tio;
-        int fd = qemu_open(path, O_RDWR | O_NOCTTY | O_NONBLOCK);
+
+        assert(fd < 0);
+        fd = qemu_open(path, O_RDWR | O_NOCTTY | O_NONBLOCK);
         if (fd == -1) {
             g_critical("error opening channel: %s", strerror(errno));
             return false;
@@ -183,37 +187,41 @@ static gboolean ga_channel_open(GAChannel *c, const gchar *path, GAChannelMethod
         break;
     }
     case GA_CHANNEL_UNIX_LISTEN: {
-        Error *local_err = NULL;
-        int fd = unix_listen(path, NULL, strlen(path), &local_err);
-        if (local_err != NULL) {
-            g_critical("%s", error_get_pretty(local_err));
-            error_free(local_err);
-            return false;
+        if (fd < 0) {
+            Error *local_err = NULL;
+
+            fd = unix_listen(path, NULL, strlen(path), &local_err);
+            if (local_err != NULL) {
+                g_critical("%s", error_get_pretty(local_err));
+                error_free(local_err);
+                return false;
+            }
         }
         ga_channel_listen_add(c, fd, true);
         break;
     }
     case GA_CHANNEL_VSOCK_LISTEN: {
-        Error *local_err = NULL;
-        SocketAddress *addr;
-        char *addr_str;
-        int fd;
-
-        addr_str = g_strdup_printf("vsock:%s", path);
-        addr = socket_parse(addr_str, &local_err);
-        g_free(addr_str);
-        if (local_err != NULL) {
-            g_critical("%s", error_get_pretty(local_err));
-            error_free(local_err);
-            return false;
-        }
+        if (fd < 0) {
+            Error *local_err = NULL;
+            SocketAddress *addr;
+            char *addr_str;
 
-        fd = socket_listen(addr, &local_err);
-        qapi_free_SocketAddress(addr);
-        if (local_err != NULL) {
-            g_critical("%s", error_get_pretty(local_err));
-            error_free(local_err);
-            return false;
+            addr_str = g_strdup_printf("vsock:%s", path);
+            addr = socket_parse(addr_str, &local_err);
+            g_free(addr_str);
+            if (local_err != NULL) {
+                g_critical("%s", error_get_pretty(local_err));
+                error_free(local_err);
+                return false;
+            }
+
+            fd = socket_listen(addr, &local_err);
+            qapi_free_SocketAddress(addr);
+            if (local_err != NULL) {
+                g_critical("%s", error_get_pretty(local_err));
+                error_free(local_err);
+                return false;
+            }
         }
         ga_channel_listen_add(c, fd, true);
         break;
@@ -262,13 +270,13 @@ GIOStatus ga_channel_read(GAChannel *c, gchar *buf, gsize size, gsize *count)
 }
 
 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
-                          GAChannelCallback cb, gpointer opaque)
+                          int listen_fd, GAChannelCallback cb, gpointer opaque)
 {
     GAChannel *c = g_new0(GAChannel, 1);
     c->event_cb = cb;
     c->user_data = opaque;
 
-    if (!ga_channel_open(c, path, method)) {
+    if (!ga_channel_open(c, path, method, listen_fd)) {
         g_critical("error opening channel");
         ga_channel_free(c);
         return NULL;
diff --git a/qga/channel-win32.c b/qga/channel-win32.c
index 21f9deedf6..7e6dc4d26f 100644
--- a/qga/channel-win32.c
+++ b/qga/channel-win32.c
@@ -316,7 +316,7 @@ static gboolean ga_channel_open(GAChannel *c, GAChannelMethod method,
 }
 
 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
-                          GAChannelCallback cb, gpointer opaque)
+                          int listen_fd, GAChannelCallback cb, gpointer opaque)
 {
     GAChannel *c = g_new0(GAChannel, 1);
     SECURITY_ATTRIBUTES sec_attrs;
diff --git a/qga/channel.h b/qga/channel.h
index 8fd0c8f72c..1778416115 100644
--- a/qga/channel.h
+++ b/qga/channel.h
@@ -25,7 +25,8 @@ typedef enum {
 typedef gboolean (*GAChannelCallback)(GIOCondition condition, gpointer opaque);
 
 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
-                          GAChannelCallback cb, gpointer opaque);
+                          int listen_fd, GAChannelCallback cb,
+                          gpointer opaque);
 void ga_channel_free(GAChannel *c);
 GIOStatus ga_channel_read(GAChannel *c, gchar *buf, gsize size, gsize *count);
 GIOStatus ga_channel_write_all(GAChannel *c, const gchar *buf, gsize size);
diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index ea37c097cf..73d93eb5ce 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -1243,6 +1243,9 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
          * filesystems may not implement fsfreeze for less obvious reasons.
          * these will report EOPNOTSUPP. we simply ignore these when tallying
          * the number of frozen filesystems.
+         * if a filesystem is mounted more than once (aka bind mount) a
+         * consecutive attempt to freeze an already frozen filesystem will
+         * return EBUSY.
          *
          * any other error means a failure to freeze a filesystem we
          * expect to be freezable, so return an error in those cases
@@ -1250,7 +1253,7 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
          */
         ret = ioctl(fd, FIFREEZE);
         if (ret == -1) {
-            if (errno != EOPNOTSUPP) {
+            if (errno != EOPNOTSUPP && errno != EBUSY) {
                 error_setg_errno(errp, errno, "failed to freeze %s",
                                  mount->dirname);
                 close(fd);
diff --git a/qga/main.c b/qga/main.c
index 9435bc74b8..92658bc0e2 100644
--- a/qga/main.c
+++ b/qga/main.c
@@ -28,6 +28,7 @@
 #include "qga/channel.h"
 #include "qemu/bswap.h"
 #include "qemu/help_option.h"
+#include "qemu/sockets.h"
 #ifdef _WIN32
 #include "qga/service-win32.h"
 #include "qga/vss-win32.h"
@@ -185,6 +186,37 @@ void reopen_fd_to_null(int fd)
 }
 #endif
 
+/**
+ * get_listen_fd:
+ * @consume: true to prevent future calls from succeeding
+ *
+ * Fetch a listen file descriptor that was passed via systemd socket
+ * activation.  Use @consume to prevent child processes from thinking a file
+ * descriptor was passed.
+ *
+ * Returns: file descriptor or -1 if no fd was passed
+ */
+static int get_listen_fd(bool consume)
+{
+#ifdef _WIN32
+    return -1; /* no fd passing expected, unsetenv(3) not available */
+#else
+    const char *listen_fds = getenv("LISTEN_FDS");
+    int fd = STDERR_FILENO + 1;
+
+    if (!listen_fds || strcmp(listen_fds, "1") != 0) {
+        return -1;
+    }
+
+    if (consume) {
+        unsetenv("LISTEN_FDS");
+    }
+
+    qemu_set_cloexec(fd);
+    return fd;
+#endif /* !_WIN32 */
+}
+
 static void usage(const char *cmd)
 {
     printf(
@@ -649,7 +681,8 @@ static gboolean channel_event_cb(GIOCondition condition, gpointer data)
     return true;
 }
 
-static gboolean channel_init(GAState *s, const gchar *method, const gchar *path)
+static gboolean channel_init(GAState *s, const gchar *method, const gchar *path,
+                             int listen_fd)
 {
     GAChannelMethod channel_method;
 
@@ -667,7 +700,8 @@ static gboolean channel_init(GAState *s, const gchar *method, const gchar *path)
         return false;
     }
 
-    s->channel = ga_channel_new(channel_method, path, channel_event_cb, s);
+    s->channel = ga_channel_new(channel_method, path, listen_fd,
+                                channel_event_cb, s);
     if (!s->channel) {
         g_critical("failed to create guest agent channel");
         return false;
@@ -1026,7 +1060,9 @@ static void config_dump(GAConfig *config)
 
     g_key_file_set_boolean(keyfile, "general", "daemon", config->daemonize);
     g_key_file_set_string(keyfile, "general", "method", config->method);
-    g_key_file_set_string(keyfile, "general", "path", config->channel_path);
+    if (config->channel_path) {
+        g_key_file_set_string(keyfile, "general", "path", config->channel_path);
+    }
     if (config->log_filepath) {
         g_key_file_set_string(keyfile, "general", "logfile",
                               config->log_filepath);
@@ -1295,7 +1331,9 @@ static int run_agent(GAState *s, GAConfig *config)
 #endif
 
     s->main_loop = g_main_loop_new(NULL, false);
-    if (!channel_init(ga_state, config->method, config->channel_path)) {
+
+    if (!channel_init(ga_state, config->method, config->channel_path,
+                      get_listen_fd(true))) {
         g_critical("failed to initialize guest agent channel");
         return EXIT_FAILURE;
     }
@@ -1319,6 +1357,7 @@ int main(int argc, char **argv)
     int ret = EXIT_SUCCESS;
     GAState *s = g_new0(GAState, 1);
     GAConfig *config = g_new0(GAConfig, 1);
+    int listen_fd;
 
     config->log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL;
 
@@ -1340,7 +1379,32 @@ int main(int argc, char **argv)
         config->method = g_strdup("virtio-serial");
     }
 
-    if (config->channel_path == NULL) {
+    listen_fd = get_listen_fd(false);
+    if (listen_fd >= 0) {
+        SocketAddress *addr;
+
+        g_free(config->method);
+        g_free(config->channel_path);
+        config->method = NULL;
+        config->channel_path = NULL;
+
+        addr = socket_local_address(listen_fd, NULL);
+        if (addr) {
+            if (addr->type == SOCKET_ADDRESS_KIND_UNIX) {
+                config->method = g_strdup("unix-listen");
+            } else if (addr->type == SOCKET_ADDRESS_KIND_VSOCK) {
+                config->method = g_strdup("vsock-listen");
+            }
+
+            qapi_free_SocketAddress(addr);
+        }
+
+        if (!config->method) {
+            g_critical("unsupported listen fd type");
+            ret = EXIT_FAILURE;
+            goto end;
+        }
+    } else if (config->channel_path == NULL) {
         if (strcmp(config->method, "virtio-serial") == 0) {
             /* try the default path for the virtio-serial port */
             config->channel_path = g_strdup(QGA_VIRTIO_PATH_DEFAULT);