Merge remote-tracking branch 'quintela/migration.next' into staging

[qemu.git] / qemu-nbd.c

diff --git a/qemu-nbd.c b/qemu-nbd.c
index 8b87dea5f6aba377ee3c830a3e4c29f51080498e..c26c98ef1d97ae7b8a2b375572cdb2ba1e71213f 100644 (file)
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -17,8 +17,9 @@
  */
 
 #include "qemu-common.h"
-#include "block.h"
-#include "nbd.h"
+#include "block/block.h"
+#include "block/nbd.h"
+#include "qemu/main-loop.h"
 
 #include <stdarg.h>
 #include <stdio.h>
@@ -33,16 +34,17 @@
 #include <libgen.h>
 #include <pthread.h>
 
-#define SOCKET_PATH         "/var/lock/qemu-nbd-%s"
-#define QEMU_NBD_OPT_CACHE  1
-#define QEMU_NBD_OPT_AIO    2
+#define SOCKET_PATH          "/var/lock/qemu-nbd-%s"
+#define QEMU_NBD_OPT_CACHE   1
+#define QEMU_NBD_OPT_AIO     2
+#define QEMU_NBD_OPT_DISCARD 3
 
 static NBDExport *exp;
 static int verbose;
 static char *srcpath;
 static char *sockpath;
-static bool sigterm_reported;
-static bool nbd_started;
+static int persistent = 0;
+static enum { RUNNING, TERMINATE, TERMINATING, TERMINATED } state;
 static int shared = 1;
 static int nb_fds;
 
@@ -186,7 +188,7 @@ static int find_partition(BlockDriverState *bs, int partition,
 
 static void termsig_handler(int signum)
 {
-    sigterm_reported = true;
+    state = TERMINATE;
     qemu_notify_event();
 }
 
@@ -269,10 +271,20 @@ static int nbd_can_accept(void *opaque)
     return nb_fds < shared;
 }
 
+static void nbd_export_closed(NBDExport *exp)
+{
+    assert(state == TERMINATING);
+    state = TERMINATED;
+}
+
 static void nbd_client_closed(NBDClient *client)
 {
     nb_fds--;
+    if (nb_fds == 0 && !persistent && state == RUNNING) {
+        state = TERMINATE;
+    }
     qemu_notify_event();
+    nbd_client_put(client);
 }
 
 static void nbd_accept(void *opaque)
@@ -282,7 +294,11 @@ static void nbd_accept(void *opaque)
     socklen_t addr_len = sizeof(addr);
 
     int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len);
-    nbd_started = true;
+    if (state >= TERMINATE) {
+        close(fd);
+        return;
+    }
+
     if (fd >= 0 && nbd_client_new(exp, fd, nbd_client_closed)) {
         nb_fds++;
     }
@@ -291,6 +307,7 @@ static void nbd_accept(void *opaque)
 int main(int argc, char **argv)
 {
     BlockDriverState *bs;
+    BlockDriver *drv;
     off_t dev_offset = 0;
     uint32_t nbdflags = 0;
     bool disconnect = false;
@@ -298,7 +315,7 @@ int main(int argc, char **argv)
     char *device = NULL;
     int port = NBD_DEFAULT_PORT;
     off_t fd_size;
-    const char *sopt = "hVb:o:p:rsnP:c:dvk:e:t";
+    const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:t";
     struct option lopt[] = {
         { "help", 0, NULL, 'h' },
         { "version", 0, NULL, 'V' },
@@ -316,7 +333,9 @@ int main(int argc, char **argv)
 #ifdef CONFIG_LINUX_AIO
         { "aio", 1, NULL, QEMU_NBD_OPT_AIO },
 #endif
+        { "discard", 1, NULL, QEMU_NBD_OPT_DISCARD },
         { "shared", 1, NULL, 'e' },
+        { "format", 1, NULL, 'f' },
         { "persistent", 0, NULL, 't' },
         { "verbose", 0, NULL, 'v' },
         { NULL, 0, NULL, 0 }
@@ -329,12 +348,14 @@ int main(int argc, char **argv)
     int partition = -1;
     int ret;
     int fd;
-    int persistent = 0;
     bool seen_cache = false;
+    bool seen_discard = false;
 #ifdef CONFIG_LINUX_AIO
     bool seen_aio = false;
 #endif
     pthread_t client_thread;
+    const char *fmt = NULL;
+    Error *local_err = NULL;
 
     /* The client thread uses SIGTERM to interrupt the server.  A signal
      * handler ensures that "qemu-nbd -v -c" exits with a nice status code.
@@ -376,6 +397,15 @@ int main(int argc, char **argv)
             }
             break;
 #endif
+        case QEMU_NBD_OPT_DISCARD:
+            if (seen_discard) {
+                errx(EXIT_FAILURE, "--discard can only be specified once");
+            }
+            seen_discard = true;
+            if (bdrv_parse_discard_flags(optarg, &flags) == -1) {
+                errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg);
+            }
+            break;
         case 'b':
             bindto = optarg;
             break;
@@ -429,6 +459,9 @@ int main(int argc, char **argv)
                 errx(EXIT_FAILURE, "Shared device number must be greater than 0\n");
             }
             break;
+        case 'f':
+            fmt = optarg;
+            break;
        case 't':
            persistent = 1;
            break;
@@ -526,14 +559,26 @@ int main(int argc, char **argv)
         snprintf(sockpath, 128, SOCKET_PATH, basename(device));
     }
 
+    qemu_init_main_loop();
     bdrv_init();
     atexit(bdrv_close_all);
 
+    if (fmt) {
+        drv = bdrv_find_format(fmt);
+        if (!drv) {
+            errx(EXIT_FAILURE, "Unknown file format '%s'", fmt);
+        }
+    } else {
+        drv = NULL;
+    }
+
     bs = bdrv_new("hda");
     srcpath = argv[optind];
-    if ((ret = bdrv_open(bs, srcpath, flags, NULL)) < 0) {
+    ret = bdrv_open(bs, srcpath, NULL, flags, drv, &local_err);
+    if (ret < 0) {
         errno = -ret;
-        err(EXIT_FAILURE, "Failed to bdrv_open '%s'", argv[optind]);
+        err(EXIT_FAILURE, "Failed to bdrv_open '%s': %s", argv[optind],
+            error_get_pretty(local_err));
     }
 
     fd_size = bdrv_getlength(bs);
@@ -546,7 +591,7 @@ int main(int argc, char **argv)
         }
     }
 
-    exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, NULL);
+    exp = nbd_export_new(bs, dev_offset, fd_size, nbdflags, nbd_export_closed);
 
     if (sockpath) {
         fd = unix_socket_incoming(sockpath);
@@ -571,7 +616,6 @@ int main(int argc, char **argv)
         memset(&client_thread, 0, sizeof(client_thread));
     }
 
-    qemu_init_main_loop();
     qemu_set_fd_handler2(fd, nbd_can_accept, nbd_accept, NULL,
                          (void *)(uintptr_t)fd);
 
@@ -581,14 +625,18 @@ int main(int argc, char **argv)
         err(EXIT_FAILURE, "Could not chdir to root directory");
     }
 
+    state = RUNNING;
     do {
         main_loop_wait(false);
-    } while (!sigterm_reported && (persistent || !nbd_started || nb_fds > 0));
+        if (state == TERMINATE) {
+            state = TERMINATING;
+            nbd_export_close(exp);
+            nbd_export_put(exp);
+            exp = NULL;
+        }
+    } while (state != TERMINATED);
 
-    nbd_export_close(exp);
-    nbd_export_put(exp);
     bdrv_close(bs);
-
     if (sockpath) {
         unlink(sockpath);
     }