commit 8243ccb7433e59a3faa3cca27fb6c40d6da2b37c
author Max Reitz <mreitz@redhat.com> Tue Jun 13 22:20:52 2017 +0200
committer Max Reitz <mreitz@redhat.com> Tue Jul 11 17:45:01 2017 +0200
tree 18ab94c4ea476c161f7c579c30e9203abb96afbc
parent 32a1681adc44f52e7c8a19408cd3be8452a0897b

block: Add PreallocMode to BD.bdrv_truncate()

Add a PreallocMode parameter to the bdrv_truncate() function implemented
by each block driver. Currently, we always pass PREALLOC_MODE_OFF and no
driver accepts anything else.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

block/sheepdog.c

diff --git a/block/sheepdog.c b/block/sheepdog.c
index 08d7b11..b7b7e6b 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -2153,13 +2153,20 @@
     return s->inode.vdi_size;
 }
 
-static int sd_truncate(BlockDriverState *bs, int64_t offset, Error **errp)
+static int sd_truncate(BlockDriverState *bs, int64_t offset,
+                       PreallocMode prealloc, Error **errp)
 {
     BDRVSheepdogState *s = bs->opaque;
     int ret, fd;
     unsigned int datalen;
     uint64_t max_vdi_size;
 
+    if (prealloc != PREALLOC_MODE_OFF) {
+        error_setg(errp, "Unsupported preallocation mode '%s'",
+                   PreallocMode_lookup[prealloc]);
+        return -ENOTSUP;
+    }
+
     max_vdi_size = (UINT64_C(1) << s->inode.block_size_shift) * MAX_DATA_OBJS;
     if (offset < s->inode.vdi_size) {
         error_setg(errp, "shrinking is not supported");
@@ -2448,7 +2455,7 @@
     BDRVSheepdogState *s = bs->opaque;
 
     if (offset > s->inode.vdi_size) {
-        ret = sd_truncate(bs, offset, NULL);
+        ret = sd_truncate(bs, offset, PREALLOC_MODE_OFF, NULL);
         if (ret < 0) {
             return ret;
         }