[PATCH v5 2/5] block/io: bdrv_common_block_status_above: support include_base

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

In order to reuse bdrv_common_block_status_above in
bdrv_is_allocated_above, let's support include_base parameter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/coroutines.h |  2 ++
 block/io.c         | 14 ++++++++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/block/coroutines.h b/block/coroutines.h
index f69179f5ef..1cb3128b94 100644
--- a/block/coroutines.h
+++ b/block/coroutines.h
@@ -41,6 +41,7 @@ bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes,
 int coroutine_fn
 bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   BlockDriverState *base,
+                                  bool include_base,
                                   bool want_zero,
                                   int64_t offset,
                                   int64_t bytes,
@@ -50,6 +51,7 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
 int generated_co_wrapper
 bdrv_common_block_status_above(BlockDriverState *bs,
                                BlockDriverState *base,
+                               bool include_base,
                                bool want_zero,
                                int64_t offset,
                                int64_t bytes,
diff --git a/block/io.c b/block/io.c
index f2a89d9417..c3ef387f7e 100644
--- a/block/io.c
+++ b/block/io.c
@@ -2357,6 +2357,7 @@ early_out:
 int coroutine_fn
 bdrv_co_common_block_status_above(BlockDriverState *bs,
                                   BlockDriverState *base,
+                                  bool include_base,
                                   bool want_zero,
                                   int64_t offset,
                                   int64_t bytes,
@@ -2368,8 +2369,8 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
     int ret = 0;
     bool first = true;
 
-    assert(bs != base);
-    for (p = bs; p != base; p = backing_bs(p)) {
+    assert(include_base || bs != base);
+    for (p = bs; include_base || p != base; p = backing_bs(p)) {
         ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map,
                                    file);
         if (ret < 0) {
@@ -2408,6 +2409,11 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
 
         /* [offset, pnum] unallocated on this layer, which could be only
          * the first part of [offset, bytes].  */
+
+        if (p == base) {
+            break;
+        }
+
         assert(*pnum <= bytes);
         bytes = *pnum;
         first = false;
@@ -2420,7 +2426,7 @@ int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
                             int64_t offset, int64_t bytes, int64_t *pnum,
                             int64_t *map, BlockDriverState **file)
 {
-    return bdrv_common_block_status_above(bs, base, true, offset, bytes,
+    return bdrv_common_block_status_above(bs, base, false, true, offset, bytes,
                                           pnum, map, file);
 }
 
@@ -2437,7 +2443,7 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
     int ret;
     int64_t dummy;
 
-    ret = bdrv_common_block_status_above(bs, backing_bs(bs), false, offset,
+    ret = bdrv_common_block_status_above(bs, bs, true, false, offset,
                                          bytes, pnum ? pnum : &dummy, NULL,
                                          NULL);
     if (ret < 0) {
-- 
2.21.0