[Qemu-devel] [PATCH v2 01/13] block: Make essential BlockDriver objects public

[Max Reitz <mreitz@redhat.com>]

There are some block drivers which are essential to QEMU and may not be
removed: These are raw, file and qcow2 (as the default non-raw format).
Make their BlockDriver objects public so they can be directly referenced
throughout the block layer without needing to call bdrv_find_format()
and having to deal with an error at runtime, while the real problem
occured during linking (where raw, file or qcow2 were not linked into
qemu).

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 block/qcow2.c             | 4 ++--
 block/raw-posix.c         | 4 ++--
 block/raw-win32.c         | 4 ++--
 block/raw_bsd.c           | 4 ++--
 include/block/block_int.h | 8 ++++++++
 5 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/block/qcow2.c b/block/qcow2.c
index 8b9ffc4..0eeba36 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2847,7 +2847,7 @@ static QemuOptsList qcow2_create_opts = {
     }
 };
 
-static BlockDriver bdrv_qcow2 = {
+BlockDriver *bdrv_qcow2 = &(BlockDriver){
     .format_name        = "qcow2",
     .instance_size      = sizeof(BDRVQcowState),
     .bdrv_probe         = qcow2_probe,
@@ -2893,7 +2893,7 @@ static BlockDriver bdrv_qcow2 = {
 
 static void bdrv_qcow2_init(void)
 {
-    bdrv_register(&bdrv_qcow2);
+    bdrv_register(bdrv_qcow2);
 }
 
 block_init(bdrv_qcow2_init);
diff --git a/block/raw-posix.c b/block/raw-posix.c
index b1af77e..6766cec 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -1684,7 +1684,7 @@ static QemuOptsList raw_create_opts = {
     }
 };
 
-static BlockDriver bdrv_file = {
+BlockDriver *bdrv_file = &(BlockDriver){
     .format_name = "file",
     .protocol_name = "file",
     .instance_size = sizeof(BDRVRawState),
@@ -2550,7 +2550,7 @@ static void bdrv_file_init(void)
      * Register all the drivers.  Note that order is important, the driver
      * registered last will get probed first.
      */
-    bdrv_register(&bdrv_file);
+    bdrv_register(bdrv_file);
     bdrv_register(&bdrv_host_device);
 #ifdef __linux__
     bdrv_register(&bdrv_host_floppy);
diff --git a/block/raw-win32.c b/block/raw-win32.c
index 7b58881..96f097e 100644
--- a/block/raw-win32.c
+++ b/block/raw-win32.c
@@ -540,7 +540,7 @@ static QemuOptsList raw_create_opts = {
     }
 };
 
-static BlockDriver bdrv_file = {
+BlockDriver *bdrv_file = &(BlockDriver){
     .format_name	= "file",
     .protocol_name	= "file",
     .instance_size	= sizeof(BDRVRawState),
@@ -721,7 +721,7 @@ static BlockDriver bdrv_host_device = {
 
 static void bdrv_file_init(void)
 {
-    bdrv_register(&bdrv_file);
+    bdrv_register(bdrv_file);
     bdrv_register(&bdrv_host_device);
 }
 
diff --git a/block/raw_bsd.c b/block/raw_bsd.c
index 401b967..cdb019e 100644
--- a/block/raw_bsd.c
+++ b/block/raw_bsd.c
@@ -173,7 +173,7 @@ static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
     return 1;
 }
 
-static BlockDriver bdrv_raw = {
+BlockDriver *bdrv_raw = &(BlockDriver){
     .format_name          = "raw",
     .bdrv_probe           = &raw_probe,
     .bdrv_reopen_prepare  = &raw_reopen_prepare,
@@ -202,7 +202,7 @@ static BlockDriver bdrv_raw = {
 
 static void bdrv_raw_init(void)
 {
-    bdrv_register(&bdrv_raw);
+    bdrv_register(bdrv_raw);
 }
 
 block_init(bdrv_raw_init);
diff --git a/include/block/block_int.h b/include/block/block_int.h
index a1c17b9..2ff3fc4 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -411,6 +411,14 @@ struct BlockDriverState {
     Error *backing_blocker;
 };
 
+
+/* Essential block drivers which must always be statically linked into qemu, and
+ * which therefore can be accessed without using bdrv_find_format() */
+extern BlockDriver *bdrv_file;
+extern BlockDriver *bdrv_raw;
+extern BlockDriver *bdrv_qcow2;
+
+
 int get_tmp_filename(char *filename, int size);
 
 void bdrv_set_io_limits(BlockDriverState *bs,
-- 
1.9.3