[PATCH v3 1/4] block: Add trivial backing_fmt support to qcow, sheepdog, vmdk
For qcow2 and qed, we want to encourage the use of -F always, as these
formats can suffer from data corruption or security holes if backing
format is probed. But for other formats, the backing format cannot be
recorded. Making the user decide on a per-format basis whether to
supply a backing format string is awkward, better is to just blindly
accept a backing format argument even if it is ignored by the
contraints of the format at hand.
Signed-off-by: Eric Blake <eblake(a)redhat.com>
---
block/qcow.c | 6 ++++++
block/sheepdog.c | 6 ++++++
block/vmdk.c | 5 +++++
3 files changed, 17 insertions(+)
diff --git a/block/qcow.c b/block/qcow.c
index fce89898681f..d05c3d526170 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -947,6 +947,7 @@ static int coroutine_fn qcow_co_create_opts(const char *filename,
static const QDictRenames opt_renames[] = {
{ BLOCK_OPT_BACKING_FILE, "backing-file" },
+ { BLOCK_OPT_BACKING_FMT, "backing-fmt" },
{ BLOCK_OPT_ENCRYPT, BLOCK_OPT_ENCRYPT_FORMAT },
{ NULL, NULL },
};
@@ -1151,6 +1152,11 @@ static QemuOptsList qcow_create_opts = {
.type = QEMU_OPT_STRING,
.help = "File name of a base image"
},
+ {
+ .name = BLOCK_OPT_BACKING_FMT,
+ .type = QEMU_OPT_STRING,
+ .help = "Ignored (use raw backing files with caution)",
+ },
{
.name = BLOCK_OPT_ENCRYPT,
.type = QEMU_OPT_BOOL,
diff --git a/block/sheepdog.c b/block/sheepdog.c
index cfa84338a2d6..248dcf4dfa01 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -2187,6 +2187,7 @@ static int coroutine_fn sd_co_create_opts(const char *filename,
QemuOpts *opts,
/* Change legacy command line options into QMP ones */
static const QDictRenames opt_renames[] = {
{ BLOCK_OPT_BACKING_FILE, "backing-file" },
+ { BLOCK_OPT_BACKING_FMT, "backing-fmt" },
{ BLOCK_OPT_OBJECT_SIZE, "object-size" },
{ NULL, NULL },
};
@@ -3189,6 +3190,11 @@ static QemuOptsList sd_create_opts = {
.type = QEMU_OPT_STRING,
.help = "File name of a base image"
},
+ {
+ .name = BLOCK_OPT_BACKING_FMT,
+ .type = QEMU_OPT_STRING,
+ .help = "Ignored (use raw backing files with caution)",
+ },
{
.name = BLOCK_OPT_PREALLOC,
.type = QEMU_OPT_STRING,
diff --git a/block/vmdk.c b/block/vmdk.c
index 20e909d99794..53f3d864f3fe 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -3005,6 +3005,11 @@ static QemuOptsList vmdk_create_opts = {
.type = QEMU_OPT_STRING,
.help = "File name of a base image"
},
+ {
+ .name = BLOCK_OPT_BACKING_FMT,
+ .type = QEMU_OPT_STRING,
+ .help = "Ignored (base image must be vmdk format)",
+ },
{
.name = BLOCK_OPT_COMPAT6,
.type = QEMU_OPT_BOOL,
--
2.25.1