block stream: close unused files and update ->backing_hd

Close the now unused images that were part of the previous backing file
chain and adjust ->backing_hd, backing_filename and backing_format
properly.

Fixes https://bugzilla.redhat.com/show_bug.cgi?id=801449

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Marcelo Tosatti 2012-03-26 21:22:10 -03:00 committed by Kevin Wolf
parent 28d3d1658a
commit 5a67a1048e
1 changed files with 34 additions and 0 deletions

View File

@ -76,6 +76,39 @@ static int coroutine_fn stream_populate(BlockDriverState *bs,
return bdrv_co_copy_on_readv(bs, sector_num, nb_sectors, &qiov);
}
static void close_unused_images(BlockDriverState *top, BlockDriverState *base,
const char *base_id)
{
BlockDriverState *intermediate;
intermediate = top->backing_hd;
while (intermediate) {
BlockDriverState *unused;
/* reached base */
if (intermediate == base) {
break;
}
unused = intermediate;
intermediate = intermediate->backing_hd;
unused->backing_hd = NULL;
bdrv_delete(unused);
}
top->backing_hd = base;
pstrcpy(top->backing_file, sizeof(top->backing_file), "");
pstrcpy(top->backing_format, sizeof(top->backing_format), "");
if (base_id) {
pstrcpy(top->backing_file, sizeof(top->backing_file), base_id);
if (base->drv) {
pstrcpy(top->backing_format, sizeof(top->backing_format),
base->drv->format_name);
}
}
}
/*
* Given an image chain: [BASE] -> [INTER1] -> [INTER2] -> [TOP]
*
@ -223,6 +256,7 @@ retry:
base_id = s->backing_file_id;
}
ret = bdrv_change_backing_file(bs, base_id, NULL);
close_unused_images(bs, base, base_id);
}
qemu_vfree(buf);