Merge remote-tracking branch 'stefanha/block' into staging

# By Kevin Wolf (4) and others
# Via Stefan Hajnoczi
* stefanha/block:
  dataplane: support viostor virtio-pci status bit setting
  dataplane: avoid reentrancy during virtio_blk_data_plane_stop()
  win32-aio: use iov utility functions instead of open-coding them
  win32-aio: Fix memory leak
  win32-aio: Fix vectored reads
  aio: Fix return value of aio_poll()
  ide: Remove wrong assertion
  block: fix null-pointer bug on error case in block commit

aio-posix.c

@@ -264,5 +264,6 @@ bool aio_poll(AioContext *ctx, bool blocking)
         }
     }
 
-    return progress;
+    assert(progress || busy);
+    return true;
 }

aio-win32.c

@@ -214,5 +214,6 @@ bool aio_poll(AioContext *ctx, bool blocking)
         events[ret - WAIT_OBJECT_0] = events[--count];
     }
 
-    return progress;
+    assert(progress || busy);
+    return true;
 }

block/commit.c

@@ -65,7 +65,7 @@ static void coroutine_fn commit_run(void *opaque)
     BlockDriverState *active = s->active;
     BlockDriverState *top = s->top;
     BlockDriverState *base = s->base;
-    BlockDriverState *overlay_bs = NULL;
+    BlockDriverState *overlay_bs;
     int64_t sector_num, end;
     int ret = 0;
     int n = 0;
@@ -92,8 +92,6 @@ static void coroutine_fn commit_run(void *opaque)
         }
     }
 
-    overlay_bs = bdrv_find_overlay(active, top);
-
     end = s->common.len >> BDRV_SECTOR_BITS;
     buf = qemu_blockalign(top, COMMIT_BUFFER_SIZE);
 
@@ -156,7 +154,8 @@ static void coroutine_fn commit_run(void *opaque)
     if (s->base_flags != bdrv_get_flags(base)) {
         bdrv_reopen(base, s->base_flags, NULL);
     }
-    if (s->orig_overlay_flags != bdrv_get_flags(overlay_bs)) {
+    overlay_bs = bdrv_find_overlay(active, top);
+    if (overlay_bs && s->orig_overlay_flags != bdrv_get_flags(overlay_bs)) {
         bdrv_reopen(overlay_bs, s->orig_overlay_flags, NULL);
     }
 

block/win32-aio.c

@@ -29,6 +29,7 @@
 #include "block/aio.h"
 #include "raw-aio.h"
 #include "qemu/event_notifier.h"
+#include "qemu/iov.h"
 #include <windows.h>
 #include <winioctl.h>
 
@@ -80,15 +81,9 @@ static void win32_aio_process_completion(QEMUWin32AIOState *s,
     if (!waiocb->is_linear) {
         if (ret == 0 && waiocb->is_read) {
             QEMUIOVector *qiov = waiocb->qiov;
-            char *p = waiocb->buf;
-            int i;
-
-            for (i = 0; i < qiov->niov; ++i) {
-                memcpy(p, qiov->iov[i].iov_base, qiov->iov[i].iov_len);
-                p += qiov->iov[i].iov_len;
-            }
-            qemu_vfree(waiocb->buf);
+            iov_from_buf(qiov->iov, qiov->niov, 0, waiocb->buf, qiov->size);
         }
+        qemu_vfree(waiocb->buf);
     }
 
 
@@ -153,13 +148,7 @@ BlockDriverAIOCB *win32_aio_submit(BlockDriverState *bs,
     if (qiov->niov > 1) {
         waiocb->buf = qemu_blockalign(bs, qiov->size);
         if (type & QEMU_AIO_WRITE) {
-            char *p = waiocb->buf;
-            int i;
-
-            for (i = 0; i < qiov->niov; ++i) {
-                memcpy(p, qiov->iov[i].iov_base, qiov->iov[i].iov_len);
-                p += qiov->iov[i].iov_len;
-            }
+            iov_to_buf(qiov->iov, qiov->niov, 0, waiocb->buf, qiov->size);
         }
         waiocb->is_linear = false;
     } else {

hw/dataplane/virtio-blk.c

@@ -40,6 +40,7 @@ typedef struct {
 
 struct VirtIOBlockDataPlane {
     bool started;
+    bool stopping;
     QEMUBH *start_bh;
     QemuThread thread;
 
@@ -357,7 +358,7 @@ static void *data_plane_thread(void *opaque)
 
     do {
         event_poll(&s->event_poll);
-    } while (s->started || s->num_reqs > 0);
+    } while (!s->stopping || s->num_reqs > 0);
     return NULL;
 }
 
@@ -486,10 +487,10 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s)
 
 void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
 {
-    if (!s->started) {
+    if (!s->started || s->stopping) {
         return;
     }
-    s->started = false;
+    s->stopping = true;
     trace_virtio_blk_data_plane_stop(s);
 
     /* Stop thread or cancel pending thread creation BH */
@@ -511,4 +512,6 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
     s->vdev->binding->set_guest_notifiers(s->vdev->binding_opaque, 1, false);
 
     vring_teardown(&s->vring);
+    s->started = false;
+    s->stopping = false;
 }

hw/ide/pci.c

@@ -311,7 +311,6 @@ void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val)
             if (bm->bus->dma->aiocb) {
                 bdrv_drain_all();
                 assert(bm->bus->dma->aiocb == NULL);
-                assert((bm->status & BM_STATUS_DMAING) == 0);
             }
         } else {
             bm->cur_addr = bm->addr;

hw/virtio-blk.c

@@ -571,7 +571,8 @@ static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
     uint32_t features;
 
 #ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
-    if (s->dataplane && !(status & VIRTIO_CONFIG_S_DRIVER)) {
+    if (s->dataplane && !(status & (VIRTIO_CONFIG_S_DRIVER |
+                                    VIRTIO_CONFIG_S_DRIVER_OK))) {
         virtio_blk_data_plane_stop(s->dataplane);
     }
 #endif

include/block/aio.h

@@ -173,16 +173,14 @@ bool aio_pending(AioContext *ctx);
  * aio as a result of executing I/O completion or bh callbacks.
  *
  * If there is no pending AIO operation or completion (bottom half),
- * return false.  If there are pending bottom halves, return true.
+ * return false.  If there are pending AIO operations of bottom halves,
+ * return true.
  *
  * If there are no pending bottom halves, but there are pending AIO
  * operations, it may not be possible to make any progress without
  * blocking.  If @blocking is true, this function will wait until one
  * or more AIO events have completed, to ensure something has moved
  * before returning.
- *
- * If @blocking is false, this function will also return false if the
- * function cannot make any progress without blocking.
  */
 bool aio_poll(AioContext *ctx, bool blocking);
 

tests/test-aio.c

@@ -315,13 +315,13 @@ static void test_wait_event_notifier_noflush(void)
     event_notifier_set(&data.e);
     g_assert(aio_poll(ctx, false));
     g_assert_cmpint(data.n, ==, 1);
-    g_assert(!aio_poll(ctx, false));
+    g_assert(aio_poll(ctx, false));
     g_assert_cmpint(data.n, ==, 1);
 
     event_notifier_set(&data.e);
     g_assert(aio_poll(ctx, false));
     g_assert_cmpint(data.n, ==, 2);
-    g_assert(!aio_poll(ctx, false));
+    g_assert(aio_poll(ctx, false));
     g_assert_cmpint(data.n, ==, 2);
 
     event_notifier_set(&dummy.e);