qemu-storage-daemon: Add --blockdev option

This adds a --blockdev option to the storage daemon that works the same
as the -blockdev option of the system emulator.

In order to be able to link with blockdev.o, we also need to change
stream.o from common-obj to block-obj, which is where all other block
jobs already are.

In contrast to the system emulator, qemu-storage-daemon options will be
processed in the order they are given. The user needs to take care to
refer to other objects only after defining them.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200224143008.13362-7-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

4 files changed, 43 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 2bf59d4f42..7c75440182 100644
--- a/Makefile
+++ b/Makefile
@@ -450,6 +450,8 @@ dummy := $(call unnest-vars,, \
                 qga-vss-dll-obj-y \
                 block-obj-y \
                 block-obj-m \
+                storage-daemon-obj-y \
+                storage-daemon-obj-m \
                 crypto-obj-y \
                 qom-obj-y \
                 io-obj-y \
@@ -482,6 +484,7 @@ TARGET_DIRS_RULES := $(foreach t, all fuzz clean install, $(addsuffix /$(t), $(T
 SOFTMMU_ALL_RULES=$(filter %-softmmu/all, $(TARGET_DIRS_RULES))
 $(SOFTMMU_ALL_RULES): $(authz-obj-y)
 $(SOFTMMU_ALL_RULES): $(block-obj-y)
+$(SOFTMMU_ALL_RULES): $(storage-daemon-obj-y)
 $(SOFTMMU_ALL_RULES): $(chardev-obj-y)
 $(SOFTMMU_ALL_RULES): $(crypto-obj-y)
 $(SOFTMMU_ALL_RULES): $(io-obj-y)
@@ -586,7 +589,7 @@ qemu-img.o: qemu-img-cmds.h
 qemu-img$(EXESUF): qemu-img.o $(authz-obj-y) $(block-obj-y) $(crypto-obj-y) $(io-obj-y) $(qom-obj-y) $(COMMON_LDADDS)
 qemu-nbd$(EXESUF): qemu-nbd.o $(authz-obj-y) $(block-obj-y) $(crypto-obj-y) $(io-obj-y) $(qom-obj-y) $(COMMON_LDADDS)
 qemu-io$(EXESUF): qemu-io.o $(authz-obj-y) $(block-obj-y) $(crypto-obj-y) $(io-obj-y) $(qom-obj-y) $(COMMON_LDADDS)
-qemu-storage-daemon$(EXESUF): qemu-storage-daemon.o $(authz-obj-y) $(block-obj-y) $(crypto-obj-y) $(io-obj-y) $(qom-obj-y) $(COMMON_LDADDS)
+qemu-storage-daemon$(EXESUF): qemu-storage-daemon.o $(authz-obj-y) $(block-obj-y) $(crypto-obj-y) $(io-obj-y) $(qom-obj-y) $(storage-daemon-obj-y) $(COMMON_LDADDS)
 
 qemu-bridge-helper$(EXESUF): qemu-bridge-helper.o $(COMMON_LDADDS)
 
diff --git a/Makefile.objs b/Makefile.objs
index 8a1cbe8000..3db3a7db6e 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -27,6 +27,13 @@ io-obj-y = io/
 
 endif # CONFIG_SOFTMMU or CONFIG_TOOLS
 
+#######################################################################
+# storage-daemon-obj-y is code used by qemu-storage-daemon (these objects are
+# used for system emulation, too, but specified separately there)
+
+storage-daemon-obj-y = block/
+storage-daemon-obj-y += blockdev.o iothread.o
+
 ######################################################################
 # Target independent part of system emulation. The long term path is to
 # suppress *all* target specific code in case of system emulation, i.e. a
diff --git a/block/Makefile.objs b/block/Makefile.objs
index e06cf0b284..cb36ae2503 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -46,7 +46,7 @@ block-obj-y += aio_task.o
 block-obj-y += backup-top.o
 block-obj-y += filter-compress.o
 
-common-obj-y += stream.o
+block-obj-y += stream.o
 
 common-obj-y += qapi-sysemu.o
 
diff --git a/qemu-storage-daemon.c b/qemu-storage-daemon.c
index fc4aef572b..c30caaf59e 100644
--- a/qemu-storage-daemon.c
+++ b/qemu-storage-daemon.c
@@ -31,6 +31,10 @@
 #include "crypto/init.h"
 
 #include "qapi/error.h"
+#include "qapi/qapi-visit-block-core.h"
+#include "qapi/qapi-commands-block-core.h"
+#include "qapi/qobject-input-visitor.h"
+
 #include "qemu-common.h"
 #include "qemu-version.h"
 #include "qemu/config-file.h"
@@ -52,15 +56,27 @@ static void help(void)
 "                         specify tracing options\n"
 "  -V, --version          output version information and exit\n"
 "\n"
+"  --blockdev [driver=]<driver>[,node-name=<N>][,discard=ignore|unmap]\n"
+"             [,cache.direct=on|off][,cache.no-flush=on|off]\n"
+"             [,read-only=on|off][,auto-read-only=on|off]\n"
+"             [,force-share=on|off][,detect-zeroes=on|off|unmap]\n"
+"             [,driver specific parameters...]\n"
+"                         configure a block backend\n"
+"\n"
 QEMU_HELP_BOTTOM "\n",
     error_get_progname());
 }
 
+enum {
+    OPTION_BLOCKDEV = 256,
+};
+
 static void process_options(int argc, char *argv[])
 {
     int c;
 
     static const struct option long_options[] = {
+        {"blockdev", required_argument, NULL, OPTION_BLOCKDEV},
         {"help", no_argument, NULL, 'h'},
         {"trace", required_argument, NULL, 'T'},
         {"version", no_argument, NULL, 'V'},
@@ -90,6 +106,21 @@ static void process_options(int argc, char *argv[])
             printf("qemu-storage-daemon version "
                    QEMU_FULL_VERSION "\n" QEMU_COPYRIGHT "\n");
             exit(EXIT_SUCCESS);
+        case OPTION_BLOCKDEV:
+            {
+                Visitor *v;
+                BlockdevOptions *options;
+
+                v = qobject_input_visitor_new_str(optarg, "driver",
+                                                  &error_fatal);
+
+                visit_type_BlockdevOptions(v, NULL, &options, &error_fatal);
+                visit_free(v);
+
+                qmp_blockdev_add(options, &error_fatal);
+                qapi_free_BlockdevOptions(options);
+                break;
+            }
         default:
             g_assert_not_reached();
         }