[Qemu-devel] [PATCH 1/2] raw-posix: Convert to bdrv_co_flush

[Kevin Wolf <kwolf@redhat.com>]

The next patch will introduce an early return. Using a bottom half to invoke
the AIO callback wouldn't be much less code, so let's go with the native
block layer interface.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/raw-posix.c |   53 ++++++++++++++++++++++++++++++++++++++++-------------
 1 files changed, 40 insertions(+), 13 deletions(-)

diff --git a/block/raw-posix.c b/block/raw-posix.c
index a3de373..dcae88a 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -357,15 +357,42 @@ static BlockDriverAIOCB *raw_aio_writev(BlockDriverState *bs,
                           cb, opaque, QEMU_AIO_WRITE);
 }
 
-static BlockDriverAIOCB *raw_aio_flush(BlockDriverState *bs,
-        BlockDriverCompletionFunc *cb, void *opaque)
+typedef struct CoroutineIOCompletion {
+    Coroutine *coroutine;
+    int ret;
+} CoroutineIOCompletion;
+
+static void raw_aio_flush_cb(void *opaque, int ret)
+{
+    CoroutineIOCompletion *co = opaque;
+
+    co->ret = ret;
+    qemu_coroutine_enter(co->coroutine, NULL);
+}
+
+static int raw_co_flush(BlockDriverState *bs)
 {
     BDRVRawState *s = bs->opaque;
+    BlockDriverAIOCB *acb;
+    int ret;
 
-    if (fd_open(bs) < 0)
-        return NULL;
+    CoroutineIOCompletion co = {
+        .coroutine = qemu_coroutine_self(),
+    };
 
-    return paio_submit(bs, s->fd, 0, NULL, 0, cb, opaque, QEMU_AIO_FLUSH);
+    ret = fd_open(bs);
+    if (ret < 0) {
+        return ret;
+    }
+
+    acb = paio_submit(bs, s->fd, 0, NULL, 0, raw_aio_flush_cb, &co, QEMU_AIO_FLUSH);
+    if (acb == NULL) {
+        return -EIO;
+    }
+
+    qemu_coroutine_yield();
+
+    return co.ret;
 }
 
 static void raw_close(BlockDriverState *bs)
@@ -635,9 +662,9 @@ static BlockDriver bdrv_file = {
     .bdrv_create = raw_create,
     .bdrv_co_discard = raw_co_discard,
 
-    .bdrv_aio_readv = raw_aio_readv,
+    .bdrv_aio_readv  = raw_aio_readv,
     .bdrv_aio_writev = raw_aio_writev,
-    .bdrv_aio_flush = raw_aio_flush,
+    .bdrv_co_flush   = raw_co_flush,
 
     .bdrv_truncate = raw_truncate,
     .bdrv_getlength = raw_getlength,
@@ -903,9 +930,9 @@ static BlockDriver bdrv_host_device = {
     .create_options     = raw_create_options,
     .bdrv_has_zero_init = hdev_has_zero_init,
 
-    .bdrv_aio_readv	= raw_aio_readv,
-    .bdrv_aio_writev	= raw_aio_writev,
-    .bdrv_aio_flush	= raw_aio_flush,
+    .bdrv_aio_readv     = raw_aio_readv,
+    .bdrv_aio_writev    = raw_aio_writev,
+    .bdrv_co_flush      = raw_co_flush,
 
     .bdrv_truncate      = raw_truncate,
     .bdrv_getlength	= raw_getlength,
@@ -1024,7 +1051,7 @@ static BlockDriver bdrv_host_floppy = {
 
     .bdrv_aio_readv     = raw_aio_readv,
     .bdrv_aio_writev    = raw_aio_writev,
-    .bdrv_aio_flush	= raw_aio_flush,
+    .bdrv_co_flush      = raw_co_flush,
 
     .bdrv_truncate      = raw_truncate,
     .bdrv_getlength	= raw_getlength,
@@ -1123,7 +1150,7 @@ static BlockDriver bdrv_host_cdrom = {
 
     .bdrv_aio_readv     = raw_aio_readv,
     .bdrv_aio_writev    = raw_aio_writev,
-    .bdrv_aio_flush	= raw_aio_flush,
+    .bdrv_co_flush      = raw_co_flush,
 
     .bdrv_truncate      = raw_truncate,
     .bdrv_getlength     = raw_getlength,
@@ -1242,7 +1269,7 @@ static BlockDriver bdrv_host_cdrom = {
 
     .bdrv_aio_readv     = raw_aio_readv,
     .bdrv_aio_writev    = raw_aio_writev,
-    .bdrv_aio_flush	= raw_aio_flush,
+    .bdrv_co_flush      = raw_co_flush,
 
     .bdrv_truncate      = raw_truncate,
     .bdrv_getlength     = raw_getlength,
-- 
1.7.6.4