diff mbox series

[v3,07/36] qcow2: Handle full/falloc preallocation in qcow2_create2()

Message ID 20180223192549.26666-8-kwolf@redhat.com
State New
Headers show
Series x-blockdev-create for protocols and qcow2 | expand

Commit Message

Kevin Wolf Feb. 23, 2018, 7:25 p.m. UTC 
Once qcow2_create2() can be called directly on an already existing node,
we must provide the 'full' and 'falloc' preallocation modes outside of
creating the image on the protocol layer. Fortunately, we have
preallocated truncate now which can provide this functionality.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/qcow2.c | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)
diff mbox series

Patch

diff --git a/block/qcow2.c b/block/qcow2.c
index 9a2028b3cf..64bf2863cd 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2872,6 +2872,25 @@  static int qcow2_create2(BlockdevCreateOptions *create_options, Error **errp)
     }
     blk_set_allow_write_beyond_eof(blk, true);
 
+    /* Clear the protocol layer and preallocate it if necessary */
+    ret = blk_truncate(blk, 0, PREALLOC_MODE_OFF, errp);
+    if (ret < 0) {
+        goto out;
+    }
+
+    if (qcow2_opts->preallocation == PREALLOC_MODE_FULL ||
+        qcow2_opts->preallocation == PREALLOC_MODE_FALLOC)
+    {
+        int64_t prealloc_size =
+            qcow2_calc_prealloc_size(qcow2_opts->size, cluster_size,
+                                     refcount_order);
+
+        ret = blk_truncate(blk, prealloc_size, qcow2_opts->preallocation, errp);
+        if (ret < 0) {
+            goto out;
+        }
+    }
+
     /* Write the header */
     QEMU_BUILD_BUG_ON((1 << MIN_CLUSTER_BITS) < sizeof(*header));
     header = g_malloc0(cluster_size);
@@ -3108,15 +3127,6 @@  static int qcow2_create(const char *filename, QemuOpts *opts, Error **errp)
 
 
     /* Create and open the file (protocol layer) */
-    if (prealloc == PREALLOC_MODE_FULL || prealloc == PREALLOC_MODE_FALLOC) {
-        int refcount_order = ctz32(refcount_bits);
-        int64_t prealloc_size =
-            qcow2_calc_prealloc_size(size, cluster_size, refcount_order);
-        qemu_opt_set_number(opts, BLOCK_OPT_SIZE, prealloc_size, &error_abort);
-        qemu_opt_set(opts, BLOCK_OPT_PREALLOC, PreallocMode_str(prealloc),
-                     &error_abort);
-    }
-
     ret = bdrv_create_file(filename, opts, errp);
     if (ret < 0) {
         goto finish;