[Qemu-devel] [PATCH v8 09/21] null: Switch to .bdrv_co_block_status()

[Eric Blake <eblake@redhat.com>]

We are gradually moving away from sector-based interfaces, towards
byte-based.  Update the null driver accordingly.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>

---
v6-v7: no change
v5: minor fix to type of 'ret'
v4: rebase to interface tweak
v3: no change
v2: rebase to mapping parameter
---
 block/null.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/block/null.c b/block/null.c
index 214d394fff4..806a8631e4d 100644
--- a/block/null.c
+++ b/block/null.c
@@ -223,22 +223,23 @@ static int null_reopen_prepare(BDRVReopenState *reopen_state,
     return 0;
 }

-static int64_t coroutine_fn null_co_get_block_status(BlockDriverState *bs,
-                                                     int64_t sector_num,
-                                                     int nb_sectors, int *pnum,
-                                                     BlockDriverState **file)
+static int coroutine_fn null_co_block_status(BlockDriverState *bs,
+                                             bool want_zero, int64_t offset,
+                                             int64_t bytes, int64_t *pnum,
+                                             int64_t *map,
+                                             BlockDriverState **file)
 {
     BDRVNullState *s = bs->opaque;
-    off_t start = sector_num * BDRV_SECTOR_SIZE;
+    int ret = BDRV_BLOCK_OFFSET_VALID;

-    *pnum = nb_sectors;
+    *pnum = bytes;
+    *map = offset;
     *file = bs;

     if (s->read_zeroes) {
-        return BDRV_BLOCK_OFFSET_VALID | start | BDRV_BLOCK_ZERO;
-    } else {
-        return BDRV_BLOCK_OFFSET_VALID | start;
+        ret |= BDRV_BLOCK_ZERO;
     }
+    return ret;
 }

 static void null_refresh_filename(BlockDriverState *bs, QDict *opts)
@@ -270,7 +271,7 @@ static BlockDriver bdrv_null_co = {
     .bdrv_co_flush_to_disk  = null_co_flush,
     .bdrv_reopen_prepare    = null_reopen_prepare,

-    .bdrv_co_get_block_status   = null_co_get_block_status,
+    .bdrv_co_block_status   = null_co_block_status,

     .bdrv_refresh_filename  = null_refresh_filename,
 };
@@ -290,7 +291,7 @@ static BlockDriver bdrv_null_aio = {
     .bdrv_aio_flush         = null_aio_flush,
     .bdrv_reopen_prepare    = null_reopen_prepare,

-    .bdrv_co_get_block_status   = null_co_get_block_status,
+    .bdrv_co_block_status   = null_co_block_status,

     .bdrv_refresh_filename  = null_refresh_filename,
 };
-- 
2.14.3