[Qemu-devel] [6872] Implement cancellation method for dma async I/O (Avi Kivity)

[Anthony Liguori]

Revision: 6872
          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6872
Author:   aliguori
Date:     2009-03-20 18:26:07 +0000 (Fri, 20 Mar 2009)
Log Message:
-----------
Implement cancellation method for dma async I/O (Avi Kivity)

Move the dma helpers to a private aio pool, and implement a cancellation
method for them.  Should prevent issues when cancelling I/O while dma is
in progress.

Signed-off-by: Avi Kivity <address@hidden>
Signed-off-by: Anthony Liguori <address@hidden>

Modified Paths:
--------------
    trunk/dma-helpers.c
    trunk/dma.h
    trunk/vl.c

Modified: trunk/dma-helpers.c
===================================================================
--- trunk/dma-helpers.c 2009-03-20 18:26:03 UTC (rev 6871)
+++ trunk/dma-helpers.c 2009-03-20 18:26:07 UTC (rev 6872)
@@ -10,6 +10,8 @@
 #include "dma.h"
 #include "block_int.h"
 
+static AIOPool dma_aio_pool;
+
 void qemu_sglist_init(QEMUSGList *qsg, int alloc_hint)
 {
     qsg->sg = qemu_malloc(alloc_hint * sizeof(ScatterGatherEntry));
@@ -126,7 +128,7 @@
     DMABlockState *dbs = qemu_malloc(sizeof(*dbs));
 
     dbs->bs = bs;
-    dbs->acb = qemu_aio_get(bs, cb, opaque);
+    dbs->acb = qemu_aio_get_pool(&dma_aio_pool, bs, cb, opaque);
     dbs->sg = sg;
     dbs->sector_num = sector_num;
     dbs->sg_cur_index = 0;
@@ -153,3 +155,14 @@
     return dma_bdrv_io(bs, sg, sector, cb, opaque, 1);
 }
 
+static void dma_aio_cancel(BlockDriverAIOCB *acb)
+{
+    DMABlockState *dbs = (DMABlockState *)acb->opaque;
+
+    bdrv_aio_cancel(dbs->acb);
+}
+
+void dma_helper_init(void)
+{
+    aio_pool_init(&dma_aio_pool, sizeof(BlockDriverAIOCB), dma_aio_cancel);
+}

Modified: trunk/dma.h
===================================================================
--- trunk/dma.h 2009-03-20 18:26:03 UTC (rev 6871)
+++ trunk/dma.h 2009-03-20 18:26:07 UTC (rev 6872)
@@ -37,5 +37,6 @@
 BlockDriverAIOCB *dma_bdrv_write(BlockDriverState *bs,
                                  QEMUSGList *sg, uint64_t sector,
                                  BlockDriverCompletionFunc *cb, void *opaque);
+void dma_helper_init(void);
 
 #endif

Modified: trunk/vl.c
===================================================================
--- trunk/vl.c  2009-03-20 18:26:03 UTC (rev 6871)
+++ trunk/vl.c  2009-03-20 18:26:07 UTC (rev 6872)
@@ -5515,6 +5515,7 @@
     cpu_exec_init_all(tb_size * 1024 * 1024);
 
     bdrv_init();
+    dma_helper_init();
 
     /* we always create the cdrom drive, even if no disk is there */