block/gluster: Do not force-cap *pnum

bdrv_co_block_status() does it for us, we do not need to do it here.

The advantage of not capping *pnum is that bdrv_co_block_status() can
cache larger data regions than requested by its caller.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210812084148.14458-6-hreitz@redhat.com>

diff --git a/block/gluster.c b/block/gluster.c
index 48a04417cf94ba13dd2a19c6f8ccdfd2091f0045..d51938e447c0bcb2f0bacec469e128bb72dc58b7 100644 (file)
--- a/block/gluster.c
+++ b/block/gluster.c
@@ -1461,7 +1461,8 @@ exit:
  * the specified offset) that are known to be in the same
  * allocated/unallocated state.
  *
- * 'bytes' is the max value 'pnum' should be set to.
+ * 'bytes' is a soft cap for 'pnum'.  If the information is free, 'pnum' may
+ * well exceed it.
  *
  * (Based on raw_co_block_status() from file-posix.c.)
  */
@@ -1502,7 +1503,7 @@ static int coroutine_fn qemu_gluster_co_block_status(BlockDriverState *bs,
     } else if (data == offset) {
         /* On a data extent, compute bytes to the end of the extent,
          * possibly including a partial sector at EOF. */
-        *pnum = MIN(bytes, hole - offset);
+        *pnum = hole - offset;
 
         /*
          * We are not allowed to return partial sectors, though, so
@@ -1521,7 +1522,7 @@ static int coroutine_fn qemu_gluster_co_block_status(BlockDriverState *bs,
     } else {
         /* On a hole, compute bytes to the beginning of the next extent.  */
         assert(hole == offset);
-        *pnum = MIN(bytes, data - offset);
+        *pnum = data - offset;
         ret = BDRV_BLOCK_ZERO;
     }