Merge remote-tracking branch 'remotes/famz/tags/block-pull-request' into staging

# gpg: Signature made Tue 11 Apr 2017 13:10:55 BST
# gpg:                using RSA key 0xCA35624C6A9171C6
# gpg: Good signature from "Fam Zheng <famz@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 5003 7CB7 9706 0F76 F021  AD56 CA35 624C 6A91 71C6

* remotes/famz/tags/block-pull-request:
  sheepdog: Use bdrv_coroutine_enter before BDRV_POLL_WHILE
  block: Fix bdrv_co_flush early return
  block: Use bdrv_coroutine_enter to start I/O coroutines
  qemu-io-cmds: Use bdrv_coroutine_enter
  blockjob: Use bdrv_coroutine_enter to start coroutine
  block: Introduce bdrv_coroutine_enter
  async: Introduce aio_co_enter
  coroutine: Extract qemu_aio_coroutine_enter
  tests/block-job-txn: Don't start block job before adding to txn
  block: Quiesce old aio context during bdrv_set_aio_context
  block: Make bdrv_parent_drained_begin/end public

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 19 insertions, 17 deletions

diff --git a/block/block-backend.c b/block/block-backend.c
index 18ece99c6e..a8f2b3440f 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1045,7 +1045,7 @@ static int blk_prw(BlockBackend *blk, int64_t offset, uint8_t *buf,
         co_entry(&rwco);
     } else {
         Coroutine *co = qemu_coroutine_create(co_entry, &rwco);
-        qemu_coroutine_enter(co);
+        bdrv_coroutine_enter(blk_bs(blk), co);
         BDRV_POLL_WHILE(blk_bs(blk), rwco.ret == NOT_DONE);
     }
 
@@ -1152,7 +1152,7 @@ static BlockAIOCB *blk_aio_prwv(BlockBackend *blk, int64_t offset, int bytes,
     acb->has_returned = false;
 
     co = qemu_coroutine_create(co_entry, acb);
-    qemu_coroutine_enter(co);
+    bdrv_coroutine_enter(blk_bs(blk), co);
 
     acb->has_returned = true;
     if (acb->rwco.ret != NOT_DONE) {
diff --git a/block/io.c b/block/io.c
index 7321ddab3d..bae6947032 100644
--- a/block/io.c
+++ b/block/io.c
@@ -44,7 +44,7 @@ static void coroutine_fn bdrv_co_do_rw(void *opaque);
 static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs,
     int64_t offset, int count, BdrvRequestFlags flags);
 
-static void bdrv_parent_drained_begin(BlockDriverState *bs)
+void bdrv_parent_drained_begin(BlockDriverState *bs)
 {
     BdrvChild *c;
 
@@ -55,7 +55,7 @@ static void bdrv_parent_drained_begin(BlockDriverState *bs)
     }
 }
 
-static void bdrv_parent_drained_end(BlockDriverState *bs)
+void bdrv_parent_drained_end(BlockDriverState *bs)
 {
     BdrvChild *c;
 
@@ -616,7 +616,7 @@ static int bdrv_prwv_co(BdrvChild *child, int64_t offset,
         bdrv_rw_co_entry(&rwco);
     } else {
         co = qemu_coroutine_create(bdrv_rw_co_entry, &rwco);
-        qemu_coroutine_enter(co);
+        bdrv_coroutine_enter(child->bs, co);
         BDRV_POLL_WHILE(child->bs, rwco.ret == NOT_DONE);
     }
     return rwco.ret;
@@ -1880,7 +1880,7 @@ int64_t bdrv_get_block_status_above(BlockDriverState *bs,
     } else {
         co = qemu_coroutine_create(bdrv_get_block_status_above_co_entry,
                                    &data);
-        qemu_coroutine_enter(co);
+        bdrv_coroutine_enter(bs, co);
         BDRV_POLL_WHILE(bs, !data.done);
     }
     return data.ret;
@@ -2006,7 +2006,7 @@ bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos,
         };
         Coroutine *co = qemu_coroutine_create(bdrv_co_rw_vmstate_entry, &data);
 
-        qemu_coroutine_enter(co);
+        bdrv_coroutine_enter(bs, co);
         while (data.ret == -EINPROGRESS) {
             aio_poll(bdrv_get_aio_context(bs), true);
         }
@@ -2223,7 +2223,7 @@ static BlockAIOCB *bdrv_co_aio_prw_vector(BdrvChild *child,
     acb->is_write = is_write;
 
     co = qemu_coroutine_create(bdrv_co_do_rw, acb);
-    qemu_coroutine_enter(co);
+    bdrv_coroutine_enter(child->bs, co);
 
     bdrv_co_maybe_schedule_bh(acb);
     return &acb->common;
@@ -2254,7 +2254,7 @@ BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs,
     acb->req.error = -EINPROGRESS;
 
     co = qemu_coroutine_create(bdrv_aio_flush_co_entry, acb);
-    qemu_coroutine_enter(co);
+    bdrv_coroutine_enter(bs, co);
 
     bdrv_co_maybe_schedule_bh(acb);
     return &acb->common;
@@ -2278,16 +2278,17 @@ static void coroutine_fn bdrv_flush_co_entry(void *opaque)
 
 int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
 {
-    int ret;
+    int current_gen;
+    int ret = 0;
+
+    bdrv_inc_in_flight(bs);
 
     if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs) ||
         bdrv_is_sg(bs)) {
-        return 0;
+        goto early_exit;
     }
 
-    bdrv_inc_in_flight(bs);
-
-    int current_gen = bs->write_gen;
+    current_gen = bs->write_gen;
 
     /* Wait until any previous flushes are completed */
     while (bs->active_flush_req) {
@@ -2370,6 +2371,7 @@ out:
     /* Return value is ignored - it's ok if wait queue is empty */
     qemu_co_queue_next(&bs->flush_queue);
 
+early_exit:
     bdrv_dec_in_flight(bs);
     return ret;
 }
@@ -2387,7 +2389,7 @@ int bdrv_flush(BlockDriverState *bs)
         bdrv_flush_co_entry(&flush_co);
     } else {
         co = qemu_coroutine_create(bdrv_flush_co_entry, &flush_co);
-        qemu_coroutine_enter(co);
+        bdrv_coroutine_enter(bs, co);
         BDRV_POLL_WHILE(bs, flush_co.ret == NOT_DONE);
     }
 
@@ -2534,7 +2536,7 @@ int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int count)
         bdrv_pdiscard_co_entry(&rwco);
     } else {
         co = qemu_coroutine_create(bdrv_pdiscard_co_entry, &rwco);
-        qemu_coroutine_enter(co);
+        bdrv_coroutine_enter(bs, co);
         BDRV_POLL_WHILE(bs, rwco.ret == NOT_DONE);
     }
 
diff --git a/block/sheepdog.c b/block/sheepdog.c
index 1b71fc81ec..14d6327209 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -736,7 +736,7 @@ static int do_req(int sockfd, BlockDriverState *bs, SheepdogReq *hdr,
     } else {
         co = qemu_coroutine_create(do_co_req, &srco);
         if (bs) {
-            qemu_coroutine_enter(co);
+            bdrv_coroutine_enter(bs, co);
             BDRV_POLL_WHILE(bs, !srco.finished);
         } else {
             qemu_coroutine_enter(co);