From: Paolo Bonzini <pbonzini@redhat.com>
Date: Wed, 4 Sep 2013 17:00:21 +0000 (+0200)
Subject: block: keep bs->total_sectors up to date even for growable block devices
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=df2a6f29a5019707d69f6eeb30cf792841cae5aa;p=qmiga%2Fqemu.git

block: keep bs->total_sectors up to date even for growable block devices

If a BlockDriverState is growable, after every write we need to
check if bs->total_sectors might have changed.  With this change,
bdrv_getlength does not need anymore a system call.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---

diff --git a/block.c b/block.c
index 905bf34251..d9a3a7f9db 100644
--- a/block.c
+++ b/block.c
@@ -2739,6 +2739,9 @@ static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
     if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
         bs->wr_highest_sector = sector_num + nb_sectors - 1;
     }
+    if (bs->growable && ret >= 0) {
+        bs->total_sectors = MAX(bs->total_sectors, sector_num + nb_sectors);
+    }
 
     tracked_request_end(&req);
 
@@ -2813,7 +2816,7 @@ int64_t bdrv_getlength(BlockDriverState *bs)
     if (!drv)
         return -ENOMEDIUM;
 
-    if (bs->growable || bdrv_dev_has_removable_media(bs)) {
+    if (bdrv_dev_has_removable_media(bs)) {
         if (drv->bdrv_getlength) {
             return drv->bdrv_getlength(bs);
         }