From 13168d62bc035570e773e33d16d9ca2e699a5db1 Mon Sep 17 00:00:00 2001
Message-Id: <13168d62bc035570e773e33d16d9ca2e699a5db1.1368098699.git.minovotn@redhat.com>
In-Reply-To: <618a4b91ddb04b21f9dc0c1defe7693fb7cc1748.1368098699.git.minovotn@redhat.com>
References: <618a4b91ddb04b21f9dc0c1defe7693fb7cc1748.1368098699.git.minovotn@redhat.com>
From: Kevin Wolf <kwolf@redhat.com>
Date: Fri, 5 Apr 2013 19:44:50 +0200
Subject: [PATCH 11/24] qcow2: Return real error in
 qcow2_update_snapshot_refcount

RH-Author: Kevin Wolf <kwolf@redhat.com>
Message-id: <1365191091-25631-12-git-send-email-kwolf@redhat.com>
Patchwork-id: 50172
O-Subject: [RHEL-6.5 qemu-kvm PATCH 11/12] qcow2: Return real error in qcow2_update_snapshot_refcount
Bugzilla: 796011
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
RH-Acked-by: Fam Zheng <famz@redhat.com>

Bugzilla: 796011

This fixes the error message triggered by the following script:

    cat > /tmp/blkdebug.cfg <<EOF
    [inject-error]
    event = "cluster_free"
    errno = "28"
    immediately = "off"
    EOF

    $qemu_img create -f qcow2 test.qcow2 10G
    $qemu_img snapshot -c snap test.qcow2
    $qemu_img snapshot -d snap blkdebug:/tmp/blkdebug.cfg:test.qcow2

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit c2bc78b6a975ea2dcd7eee9f0dce22cc060cdcdc)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/qcow2-refcount.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

Signed-off-by: Michal Novotny <minovotn@redhat.com>
---
 block/qcow2-refcount.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 82b747b..d898324 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -729,10 +729,9 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
             l1_table = NULL;
         }
         l1_allocated = 1;
-        if (bdrv_pread(bs->file, l1_table_offset,
-                       l1_table, l1_size2) != l1_size2)
-        {
-            ret = -EIO;
+
+        ret = bdrv_pread(bs->file, l1_table_offset, l1_table, l1_size2);
+        if (ret < 0) {
             goto fail;
         }
 
@@ -787,7 +786,7 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
                         }
 
                         if (refcount < 0) {
-                            ret = -EIO;
+                            ret = refcount;
                             goto fail;
                         }
                     }
@@ -818,7 +817,7 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
                 refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
             }
             if (refcount < 0) {
-                ret = -EIO;
+                ret = refcount;
                 goto fail;
             } else if (refcount == 1) {
                 l2_offset |= QCOW_OFLAG_COPIED;
-- 
1.7.11.7