[Qemu-devel] [PATCH v9 7/9] qcow2: Resize the cache upon image resizing

Leonid Bloch posted 9 patches 7 years, 1 month ago
There is a newer version of this series
[Qemu-devel] [PATCH v9 7/9] qcow2: Resize the cache upon image resizing
Posted by Leonid Bloch 7 years, 1 month ago
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>
---
 block/qcow2.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/block/qcow2.c b/block/qcow2.c
index 01c39c56c0..1445cd5360 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -3418,6 +3418,7 @@ 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)
@@ -3642,6 +3643,8 @@ 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),
@@ -3652,6 +3655,13 @@ 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);
+    if (ret < 0) {
+        goto fail;
+    }
     ret = 0;
 fail:
     qemu_co_mutex_unlock(&s->lock);
-- 
2.17.1