From 25829686076eac2d3d6216145377ecca8f92d6bd Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Tue, 19 Feb 2019 17:00:20 +0100
Subject: [PATCH 19/23] qcow2: Resize the cache upon image resizing

RH-Author: Kevin Wolf <kwolf@redhat.com>
Message-id: <20190219170023.27826-11-kwolf@redhat.com>
Patchwork-id: 84553
O-Subject: [RHEL-7.7 qemu-kvm-rhev PATCH 10/13] qcow2: Resize the cache upon image resizing
Bugzilla: 1656913
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Max Reitz <mreitz@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

From: Leonid Bloch <lbloch@janustech.com>

The caches are now recalculated upon image resizing. This is done
because the new default behavior of assigning L2 cache relatively to
the image size, implies that the cache will be adapted accordingly
after an image resize.

Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 45b4949c7bcdcd998cb42f5c517e80a2657cfd33)
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 block/qcow2.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/block/qcow2.c b/block/qcow2.c
index fc6bddd..72f1ea8 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -3462,6 +3462,7 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
     uint64_t old_length;
     int64_t new_l1_size;
     int ret;
+    QDict *options;
 
     if (prealloc != PREALLOC_MODE_OFF && prealloc != PREALLOC_MODE_METADATA &&
         prealloc != PREALLOC_MODE_FALLOC && prealloc != PREALLOC_MODE_FULL)
@@ -3686,6 +3687,8 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
         }
     }
 
+    bs->total_sectors = offset / BDRV_SECTOR_SIZE;
+
     /* write updated header.size */
     offset = cpu_to_be64(offset);
     ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),
@@ -3696,6 +3699,14 @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset,
     }
 
     s->l1_vm_state_index = new_l1_size;
+
+    /* Update cache sizes */
+    options = qdict_clone_shallow(bs->options);
+    ret = qcow2_update_options(bs, options, s->flags, errp);
+    qobject_unref(options);
+    if (ret < 0) {
+        goto fail;
+    }
     ret = 0;
 fail:
     qemu_co_mutex_unlock(&s->lock);
-- 
1.8.3.1