[Qemu-devel] [PATCH 0/2] block: make .bdrv_close optional

[Qemu-devel] [PATCH 0/2] block: make .bdrv_close optional

[Vladimir Sementsov-Ogievskiy]

Several block drivers have to define empty .bdrv_close handler. Let's
instead make it optional.

Vladimir Sementsov-Ogievskiy (2):
  block: make .bdrv_close optional
  block: drop empty .bdrv_close handlers

 block.c              | 4 +++-
 block/blkreplay.c    | 5 -----
 block/commit.c       | 5 -----
 block/copy-on-read.c | 6 ------
 block/mirror.c       | 5 -----
 block/null.c         | 6 ------
 block/raw-format.c   | 5 -----
 block/snapshot.c     | 4 +++-
 8 files changed, 6 insertions(+), 34 deletions(-)

-- 
2.11.1

[Qemu-devel] [PATCH 1/2] block: make .bdrv_close optional

[Vladimir Sementsov-Ogievskiy]

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block.c          | 4 +++-
 block/snapshot.c | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/block.c b/block.c
index 39f373e035..9694018a68 100644
--- a/block.c
+++ b/block.c
@@ -3349,7 +3349,9 @@ static void bdrv_close(BlockDriverState *bs)
     bdrv_drain(bs); /* in case flush left pending I/O */
 
     if (bs->drv) {
-        bs->drv->bdrv_close(bs);
+        if (bs->drv->bdrv_close) {
+            bs->drv->bdrv_close(bs);
+        }
         bs->drv = NULL;
     }
 
diff --git a/block/snapshot.c b/block/snapshot.c
index f9903bc94e..3218a542df 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -218,7 +218,9 @@ int bdrv_snapshot_goto(BlockDriverState *bs,
         qobject_unref(file_options);
         qdict_put_str(options, "file", bdrv_get_node_name(file));
 
-        drv->bdrv_close(bs);
+        if (drv->bdrv_close) {
+            drv->bdrv_close(bs);
+        }
         bdrv_unref_child(bs, bs->file);
         bs->file = NULL;
 
-- 
2.11.1

[Qemu-devel] [PATCH 2/2] block: drop empty .bdrv_close handlers

[Vladimir Sementsov-Ogievskiy]

.bdrv_close handler is optional after previous commit, no needs to keep
empty functions more.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/blkreplay.c    | 5 -----
 block/commit.c       | 5 -----
 block/copy-on-read.c | 6 ------
 block/mirror.c       | 5 -----
 block/null.c         | 6 ------
 block/raw-format.c   | 5 -----
 6 files changed, 32 deletions(-)

diff --git a/block/blkreplay.c b/block/blkreplay.c
index 766150ade6..b5d9efdeca 100755
--- a/block/blkreplay.c
+++ b/block/blkreplay.c
@@ -43,10 +43,6 @@ fail:
     return ret;
 }
 
-static void blkreplay_close(BlockDriverState *bs)
-{
-}
-
 static int64_t blkreplay_getlength(BlockDriverState *bs)
 {
     return bdrv_getlength(bs->file->bs);
@@ -135,7 +131,6 @@ static BlockDriver bdrv_blkreplay = {
     .instance_size          = 0,
 
     .bdrv_open              = blkreplay_open,
-    .bdrv_close             = blkreplay_close,
     .bdrv_child_perm        = bdrv_filter_default_perms,
     .bdrv_getlength         = blkreplay_getlength,
 
diff --git a/block/commit.c b/block/commit.c
index e1814d9693..eb414579bd 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -239,10 +239,6 @@ static void bdrv_commit_top_refresh_filename(BlockDriverState *bs, QDict *opts)
             bs->backing->bs->filename);
 }
 
-static void bdrv_commit_top_close(BlockDriverState *bs)
-{
-}
-
 static void bdrv_commit_top_child_perm(BlockDriverState *bs, BdrvChild *c,
                                        const BdrvChildRole *role,
                                        BlockReopenQueue *reopen_queue,
@@ -260,7 +256,6 @@ static BlockDriver bdrv_commit_top = {
     .bdrv_co_preadv             = bdrv_commit_top_preadv,
     .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
     .bdrv_refresh_filename      = bdrv_commit_top_refresh_filename,
-    .bdrv_close                 = bdrv_commit_top_close,
     .bdrv_child_perm            = bdrv_commit_top_child_perm,
 };
 
diff --git a/block/copy-on-read.c b/block/copy-on-read.c
index a19164f9eb..64dcc424b5 100644
--- a/block/copy-on-read.c
+++ b/block/copy-on-read.c
@@ -45,11 +45,6 @@ static int cor_open(BlockDriverState *bs, QDict *options, int flags,
 }
 
 
-static void cor_close(BlockDriverState *bs)
-{
-}
-
-
 #define PERM_PASSTHROUGH (BLK_PERM_CONSISTENT_READ \
                           | BLK_PERM_WRITE \
                           | BLK_PERM_RESIZE)
@@ -143,7 +138,6 @@ BlockDriver bdrv_copy_on_read = {
     .format_name                        = "copy-on-read",
 
     .bdrv_open                          = cor_open,
-    .bdrv_close                         = cor_close,
     .bdrv_child_perm                    = cor_child_perm,
 
     .bdrv_getlength                     = cor_getlength,
diff --git a/block/mirror.c b/block/mirror.c
index d2806812c8..e949aa1fc5 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1424,10 +1424,6 @@ static void bdrv_mirror_top_refresh_filename(BlockDriverState *bs, QDict *opts)
             bs->backing->bs->filename);
 }
 
-static void bdrv_mirror_top_close(BlockDriverState *bs)
-{
-}
-
 static void bdrv_mirror_top_child_perm(BlockDriverState *bs, BdrvChild *c,
                                        const BdrvChildRole *role,
                                        BlockReopenQueue *reopen_queue,
@@ -1454,7 +1450,6 @@ static BlockDriver bdrv_mirror_top = {
     .bdrv_co_flush              = bdrv_mirror_top_flush,
     .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
     .bdrv_refresh_filename      = bdrv_mirror_top_refresh_filename,
-    .bdrv_close                 = bdrv_mirror_top_close,
     .bdrv_child_perm            = bdrv_mirror_top_child_perm,
 };
 
diff --git a/block/null.c b/block/null.c
index 5d610fdfba..d442d3e901 100644
--- a/block/null.c
+++ b/block/null.c
@@ -97,10 +97,6 @@ static int null_file_open(BlockDriverState *bs, QDict *options, int flags,
     return ret;
 }
 
-static void null_close(BlockDriverState *bs)
-{
-}
-
 static int64_t null_getlength(BlockDriverState *bs)
 {
     BDRVNullState *s = bs->opaque;
@@ -263,7 +259,6 @@ static BlockDriver bdrv_null_co = {
 
     .bdrv_file_open         = null_file_open,
     .bdrv_parse_filename    = null_co_parse_filename,
-    .bdrv_close             = null_close,
     .bdrv_getlength         = null_getlength,
 
     .bdrv_co_preadv         = null_co_preadv,
@@ -283,7 +278,6 @@ static BlockDriver bdrv_null_aio = {
 
     .bdrv_file_open         = null_file_open,
     .bdrv_parse_filename    = null_aio_parse_filename,
-    .bdrv_close             = null_close,
     .bdrv_getlength         = null_getlength,
 
     .bdrv_aio_preadv        = null_aio_preadv,
diff --git a/block/raw-format.c b/block/raw-format.c
index 2fd69cdb08..6f6dc99b2c 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -459,10 +459,6 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags,
     return 0;
 }
 
-static void raw_close(BlockDriverState *bs)
-{
-}
-
 static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
 {
     /* smallest possible positive score so that raw is used if and only if no
@@ -543,7 +539,6 @@ BlockDriver bdrv_raw = {
     .bdrv_reopen_commit   = &raw_reopen_commit,
     .bdrv_reopen_abort    = &raw_reopen_abort,
     .bdrv_open            = &raw_open,
-    .bdrv_close           = &raw_close,
     .bdrv_child_perm      = bdrv_filter_default_perms,
     .bdrv_co_create_opts  = &raw_co_create_opts,
     .bdrv_co_preadv       = &raw_co_preadv,
-- 
2.11.1

Re: [Qemu-devel] [PATCH 0/2] block: make .bdrv_close optional

[Kevin Wolf]

Am 14.08.2018 um 14:43 hat Vladimir Sementsov-Ogievskiy geschrieben:
> Several block drivers have to define empty .bdrv_close handler. Let's
> instead make it optional.

Thanks, applied to the block branch.

Kevin