[PATCH v2] launch: add support for autodetection of appliance image format
by Pavel Butsykin
This feature allows you to use different image formats for the fixed
appliance. The raw format is used by default.
Signed-off-by: Pavel Butsykin <pbutsykin(a)virtuozzo.com>
---
lib/launch-direct.c | 2 ++
lib/launch-libvirt.c | 19 ++++++++++++-------
m4/guestfs_appliance.m4 | 11 +++++++++++
3 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/lib/launch-direct.c b/lib/launch-direct.c
index 0be662e25..b9b54857a 100644
--- a/lib/launch-direct.c
+++ b/lib/launch-direct.c
@@ -592,7 +592,9 @@ launch_direct (guestfs_h *g, void *datav, const char *arg)
append_list ("id=appliance");
append_list ("cache=unsafe");
append_list ("if=none");
+#ifndef APPLIANCE_FMT_AUTO
append_list ("format=raw");
+#endif
} end_list ();
start_list ("-device") {
append_list ("scsi-hd");
diff --git a/lib/launch-libvirt.c b/lib/launch-libvirt.c
index 4adb2cfb3..030ea6911 100644
--- a/lib/launch-libvirt.c
+++ b/lib/launch-libvirt.c
@@ -212,9 +212,10 @@ get_source_format_or_autodetect (guestfs_h *g, struct drive *drv)
/**
* Create a qcow2 format overlay, with the given C<backing_drive>
- * (file). The C<format> parameter, which must be non-NULL, is the
- * backing file format. This is used to create the appliance overlay,
- * and also for read-only drives.
+ * (file). The C<format> parameter is the backing file format.
+ * The C<format> parameter can be NULL, in this case the backing
+ * format will be determined automatically. This is used to create
+ * the appliance overlay, and also for read-only drives.
*/
static char *
make_qcow2_overlay (guestfs_h *g, const char *backing_drive,
@@ -223,8 +224,6 @@ make_qcow2_overlay (guestfs_h *g, const char *backing_drive,
char *overlay;
struct guestfs_disk_create_argv optargs;
- assert (format != NULL);
-
if (guestfs_int_lazy_make_tmpdir (g) == -1)
return NULL;
@@ -232,8 +231,10 @@ make_qcow2_overlay (guestfs_h *g, const char *backing_drive,
optargs.bitmask = GUESTFS_DISK_CREATE_BACKINGFILE_BITMASK;
optargs.backingfile = backing_drive;
- optargs.bitmask |= GUESTFS_DISK_CREATE_BACKINGFORMAT_BITMASK;
- optargs.backingformat = format;
+ if (format) {
+ optargs.bitmask |= GUESTFS_DISK_CREATE_BACKINGFORMAT_BITMASK;
+ optargs.backingformat = format;
+ }
if (guestfs_disk_create_argv (g, overlay, "qcow2", -1, &optargs) == -1) {
free (overlay);
@@ -461,7 +462,11 @@ launch_libvirt (guestfs_h *g, void *datav, const char *libvirt_uri)
/* Note that appliance can be NULL if using the old-style appliance. */
if (appliance) {
+#ifdef APPLIANCE_FMT_AUTO
+ params.appliance_overlay = make_qcow2_overlay (g, appliance, NULL);
+#else
params.appliance_overlay = make_qcow2_overlay (g, appliance, "raw");
+#endif
if (!params.appliance_overlay)
goto cleanup;
}
diff --git a/m4/guestfs_appliance.m4 b/m4/guestfs_appliance.m4
index 81c43879f..4e1ec8135 100644
--- a/m4/guestfs_appliance.m4
+++ b/m4/guestfs_appliance.m4
@@ -139,3 +139,14 @@ AC_SUBST([GUESTFS_DEFAULT_PATH])
AC_DEFINE_UNQUOTED([GUESTFS_DEFAULT_PATH], ["$GUESTFS_DEFAULT_PATH"],
[Define guestfs default path.])
+
+AC_ARG_ENABLE([appliance-fmt-auto],
+ [AS_HELP_STRING([--enable-appliance-fmt-auto],
+ [enable autodetection of appliance image format @<:@default=no@:>@])],
+ [ENABLE_APPLIANCE_FMT_AUTO="$enableval"],
+ [ENABLE_APPLIANCE_FMT_AUTO=no])
+
+if test "x$ENABLE_APPLIANCE_FMT_AUTO" = "xyes"; then
+ AC_DEFINE([APPLIANCE_FMT_AUTO], [1],
+ [Define to 1 if enabled autodetection of appliance image format.])
+fi
--
2.13.0
4 years, 9 months
1.39 proposal: Let's split up the libguestfs git repo and tarballs
by Richard W.M. Jones
My contention is that the libguestfs git repository is too large and
unwieldy. There are too many separate, unrelated projects and as a
result of that the source has too many dependencies and takes too long
to build and test.
The project divides (sort of) naturally into layers -- the library,
the bindings, the various virt tools -- and could be split along those
lines into separate projects which can then be released and evolve at
their own pace.
My suggested split would be something like this:
* libguestfs: The library, daemon and appliance. That would include
the following directories in a single project:
appliance
bash
contrib
daemon
docs
examples
gnulib
lib
logo
test-tool
tmp
utils
website
* 1 project for each language binding:
csharp
erlang
gobject
golang
haskell
java
lua
ocaml
php
perl
python
ruby
* virt-customize and related tools, we'd probably call this subproject
"virt-builder". It would include virt-builder, virt-customize and
virt-sysprep, since they share a lot of common code.
* 1 project for each of the following items:
small tools written in C
(virt-cat, virt-filesystems, virt-log, virt-ls, virt-tail,
virt-diff, virt-edit, virt-format, guestmount, virt-inspector,
virt-make-fs, virt-rescue)
guestfish
virt-alignment-scan and virt-df
virt-dib
virt-get-kernel
virt-resize
virt-sparsify
virt-v2v and virt-p2v
virt-win-reg
* I'd be inclined to drop the legacy Perl tools virt-tar,
virt-list-filesystems, virt-list-partitions unless someone
especially wished to step forward to maintain them.
* common code and generator: Off to the side we'd somehow need to
package up the common code and the generator for use by all of the
above projects. It wouldn't be a separate project for downstream
packagers, but instead the code would be included (ie. duplicated)
in tarballs and upstream available as a side git repo that you'd
need to include when building (git submodule?). This is somewhat
unspecified.
M4, PO, and tests would be split between the projects as appropriate.
My proposal would be to do this incrementally, rather than all at
once, moving the easier things out first.
Thoughts?
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines. Supports shell scripting,
bindings from many languages. http://libguestfs.org
4 years, 11 months
[PATCH] v2v: rhv-upload-plugin - improve wait logic after finalize (RHBZ#1680361)
by Daniel Erez
After invoking transfer_service.finalize, check operation
status by examining ImageTransferPhase and DiskStatus.
This is done instead of failing after a predefined timeout
regardless the status.
* not verified *
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1680361
---
v2v/rhv-upload-plugin.py | 26 +++++++++++++++++++++-----
1 file changed, 21 insertions(+), 5 deletions(-)
diff --git a/v2v/rhv-upload-plugin.py b/v2v/rhv-upload-plugin.py
index 2a950c5ed..873c11ce1 100644
--- a/v2v/rhv-upload-plugin.py
+++ b/v2v/rhv-upload-plugin.py
@@ -523,14 +523,30 @@ def close(h):
# waiting for the transfer object to cease to exist, which
# falls through to the exception case and then we can
# continue.
- endt = time.time() + timeout
+ start = time.time()
try:
while True:
time.sleep(1)
- tmp = transfer_service.get()
- if time.time() > endt:
- raise RuntimeError("timed out waiting for transfer "
- "to finalize")
+ transfer = transfer_service.get()
+
+ if transfer is None:
+ disk_service = h['disk_service']
+ disk = disk_service.get()
+ if disk.status == types.DiskStatus.OK:
+ continue
+
+ if transfer.phase == types.ImageTransferPhase.FINISHED_SUCCESS:
+ debug("finalized after %s seconds", time.time() - start)
+ break
+
+ if transfer.phase ==
types.ImageTransferPhase.FINALIZING_SUCCESS:
+ if time.time() > start + timeout:
+ raise RuntimeError("timed out waiting for transfer "
+ "to finalize")
+ continue
+
+ raise RuntimeError("Unexpected transfer phase while
finalizing "
+ "upload %r" % transfer.phase)
except sdk.NotFoundError:
pass
--
5 years, 3 months
[PATCH nbdkit 0/7] server: Implement NBD_FLAG_CAN_MULTI_CONN.
by Richard W.M. Jones
First thing to say is that I need to do a *lot* more testing on this,
so this is just an early peek. In particular, although it passed
‘make check && make check-valgrind’ I have *not* tested it against a
multi-conn-aware client such as the Linux kernel >= 4.9.
This implements NBD_FLAG_CAN_MULTI_CONN, described in the protocol doc
as:
"NBD_FLAG_CAN_MULTI_CONN: Indicates that the server operates
entirely without cache, or that the cache it uses is shared among
all connections to the given device. In particular, if this flag is
present, then the effects of NBD_CMD_FLUSH and NBD_CMD_FLAG_FUA MUST
be visible across all connections when the server sends its reply to
that command to the client. In the absence of this flag, clients
SHOULD NOT multiplex their commands over more than one connection to
the export."
This is necessary to support the Linux nbd client -C option.
The only plugin which sets the flag so far is file. The ocaml, sh and
nbd plugins allow the flag to be controlled or passed through.
Notable also is that the blocksize filter has to filter out this flag,
because I'm not convinced that the bounce buffer is safe. However I
believe the other filters *are* safe (although not really certain
about the fua filter, and the new cache filter is tricky too).
My feeling is that we should set the flag unconditionally for all
readonly connections, but I can think of nasty corner cases where it
might not work. We should most probably set it in all plugins that
are readonly (eg. nbdkit-pattern-plugin).
Rich.
5 years, 6 months
[PATCH nbdkit v5 FINAL 00/19] Implement extents.
by Richard W.M. Jones
This has already been pushed upstream. I am simply posting these here
so we have a reference in the mailing list in case we find bugs later
(as I'm sure we will - it's a complex patch series).
Great thanks to Eric Blake for tireless review on this one. It also
seems to have identified a few minor bugs in qemu along the way.
Rich.
5 years, 7 months
[PATCH nbdkit] Add support for writing plugins in Rust.
by Richard W.M. Jones
This adds very rough support for writing nbdkit plugins in Rust. This
is not very idiomatic -- essentially we're handling the direct C calls
from nbdkit in Rust. We have to use ‘unsafe’ in a few places because
there's no way to tell the Rust code that nbdkit satisfies guarantees
(eg. around thread safety, always returning leaked pointers back to
the close function, always doing bounds checking).
See the TODO file changes for the mising bits.
TBH there's not much to review here.
Rich.
5 years, 7 months
[RFC PATCH] protocol: Add NBD_CMD_FLAG_FAST_ZERO
by Eric Blake
While it may be counterintuitive at first, the introduction of
NBD_CMD_WRITE_ZEROES and NBD_CMD_BLOCK_STATUS has caused a performance
regression in qemu [1], when copying a sparse file. When the
destination file must contain the same contents as the source, but it
is not known in advance whether the destination started life with all
zero content, then there are cases where it is faster to request a
bulk zero of the entire device followed by writing only the portions
of the device that are to contain data, as that results in fewer I/O
transactions overall. In fact, there are even situations where
trimming the entire device prior to writing zeroes may be faster than
bare write zero request [2]. However, if a bulk zero request ever
falls back to the same speed as a normal write, a bulk pre-zeroing
algorithm is actually a pessimization, as it ends up writing portions
of the disk twice.
[1] https://lists.gnu.org/archive/html/qemu-devel/2019-03/msg06389.html
[2] https://github.com/libguestfs/nbdkit/commit/407f8dde
Hence, it is desirable to have a way for clients to specify that a
particular write zero request is being attempted for a fast wipe, and
get an immediate failure if the zero request would otherwise take the
same time as a write. Conversely, if the client is not performing a
pre-initialization pass, it is still more efficient in terms of
networking traffic to send NBD_CMD_WRITE_ZERO requests where the
server implements the fallback to the slower write, than it is for the
client to have to perform the fallback to send NBD_CMD_WRITE with a
zeroed buffer.
Add a protocol flag and corresponding transmission advertisement flag
to make it easier for clients to inform the server of their intent. If
the server advertises NBD_FLAG_SEND_FAST_ZERO, then it promises two
things: to perform a fallback to write when the client does not
request NBD_CMD_FLAG_FAST_ZERO (so that the client benefits from the
lower network overhead); and to fail quickly with ENOTSUP if the
client requested the flag but the server cannot write zeroes more
efficiently than a normal write (so that the client is not penalized
with the time of writing data areas of the disk twice).
Note that the semantics are chosen so that servers should advertise
the new flag whether or not they have fast zeroing (that is, this is
NOT the server advertising that it has fast zeroes, but rather
advertising that the client can get feedback as needed on whether
zeroing is fast). It is also intentional that the new advertisement
includes a new errno value, ENOTSUP, with rules that this error should
not be returned for any pre-existing behaviors, must not happen when
the client does not request a fast zero, and must be returned quickly
if the client requested fast zero but anything other than the error
would not be fast; while leaving it possible for clients to
distinguish other errors like EINVAL if alignment constraints are not
met. Clients should not send the flag unless the server advertised
support, but well-behaved servers should already be reporting EINVAL
to unrecognized flags. If the server does not advertise the new
feature, clients can safely fall back to assuming that writing zeroes
is no faster than normal writes.
Note that the Linux fallocate(2) interface may or may not be powerful
enough to easily determine if zeroing will be efficient - in
particular, FALLOC_FL_ZERO_RANGE in isolation does NOT give that
insight; for block devices, it is known that ioctl(BLKZEROOUT) does
NOT have a way for userspace to probe if it is efficient or slow. But
with enough demand, the kernel may add another FALLOC_FL_ flag to use
with FALLOC_FL_ZERO_RANGE, and/or appropriate ioctls with guaranteed
ENOTSUP failures if a fast path cannot be taken. If a server cannot
easily determine if write zeroes will be efficient, it is better off
not advertising NBD_FLAG_SEND_FAST_ZERO.
Signed-off-by: Eric Blake <eblake(a)redhat.com>
---
I will not push this without both:
- a positive review (for example, we may decide that burning another
NBD_FLAG_* is undesirable, and that we should instead have some sort
of NBD_OPT_ handshake for determining when the server supports
NBD_CMF_FLAG_FAST_ZERO)
- a reference client and server implementation (probably both via qemu,
since it was qemu that raised the problem in the first place)
doc/proto.md | 44 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 43 insertions(+), 1 deletion(-)
diff --git a/doc/proto.md b/doc/proto.md
index 8aaad96..1107766 100644
--- a/doc/proto.md
+++ b/doc/proto.md
@@ -1059,6 +1059,17 @@ The field has the following format:
which support the command without advertising this bit, and
conversely that this bit does not guarantee that the command will
succeed or have an impact.
+- bit 11, `NBD_FLAG_SEND_FAST_ZERO`: allow clients to detect whether
+ `NBD_CMD_WRITE_ZEROES` is efficient. The server MUST set this
+ transmission flag to 1 if the `NBD_CMD_WRITE_ZEROES` request
+ supports the `NBD_CMD_FLAG_FAST_ZERO` flag, and MUST set this
+ transmission flag to 0 if `NBD_FLAG_SEND_WRITE_ZEROES` is not
+ set. Servers SHOULD NOT set this transmission flag if there is no
+ quick way to determine whether a particular write zeroes request
+ will be efficient, but the lack of an efficient write zero
+ implementation SHOULD NOT prevent a server from setting this
+ flag. Clients MUST NOT set the `NBD_CMD_FLAG_FAST_ZERO` request flag
+ unless this transmission flag is set.
Clients SHOULD ignore unknown flags.
@@ -1636,6 +1647,12 @@ valid may depend on negotiation during the handshake phase.
MUST NOT send metadata on more than one extent in the reply. Client
implementors should note that using this flag on multiple contiguous
requests is likely to be inefficient.
+- bit 4, `NBD_CMD_FLAG_FAST_ZERO`; valid during
+ `NBD_CMD_WRITE_ZEROES`. If set, but the server cannot perform the
+ write zeroes any faster than it would for an equivalent
+ `NBD_CMD_WRITE`, then the server MUST fail quickly with an error of
+ `ENOTSUP`. The client MUST NOT set this unless the server advertised
+ `NBD_FLAG_SEND_FAST_ZERO`.
##### Structured reply flags
@@ -2004,7 +2021,10 @@ The following request types exist:
reached permanent storage, unless `NBD_CMD_FLAG_FUA` is in use.
A client MUST NOT send a write zeroes request unless
- `NBD_FLAG_SEND_WRITE_ZEROES` was set in the transmission flags field.
+ `NBD_FLAG_SEND_WRITE_ZEROES` was set in the transmission flags
+ field. Additionally, a client MUST NOT send the
+ `NBD_CMD_FLAG_FAST_ZERO` flag unless `NBD_FLAG_SEND_FAST_ZERO` was
+ set in the transimssion flags field.
By default, the server MAY use trimming to zero out the area, even
if it did not advertise `NBD_FLAG_SEND_TRIM`; but it MUST ensure
@@ -2014,6 +2034,23 @@ The following request types exist:
same area will not cause fragmentation or cause failure due to
insufficient space.
+ If the server advertised `NBD_FLAG_SEND_FAST_ZERO` but
+ `NBD_CMD_FLAG_FAST_ZERO` is not set, then the server MUST NOT fail
+ with `ENOTSUP`, even if the operation is no faster than a
+ corresponding `NBD_CMD_WRITE`. Conversely, if
+ `NBD_CMD_FLAG_FAST_ZERO` is set, the server MUST fail quickly with
+ `ENOTSUP` unless the request can be serviced more efficiently than
+ a corresponding `NBD_CMD_WRITE`. The server's determination of
+ efficiency MAY depend on whether the request was suitably aligned,
+ on whether the `NBD_CMD_FLAG_NO_HOLE` flag was present, or even on
+ whether a previous `NBD_CMD_TRIM` had been performed on the
+ region. If the server did not advertise
+ `NBD_FLAG_SEND_FAST_ZERO`, then it SHOULD NOT fail with `ENOTSUP`,
+ regardless of the speed of servicing a request, and SHOULD fail
+ with `EINVAL` if the `NBD_CMD_FLAG_FAST_ZERO` flag was set. A
+ server MAY advertise `NBD_FLAG_SEND_FAST_ZERO` whether or not it
+ can perform efficient zeroing.
+
If an error occurs, the server MUST set the appropriate error code
in the error field.
@@ -2114,6 +2151,7 @@ The following error values are defined:
* `EINVAL` (22), Invalid argument.
* `ENOSPC` (28), No space left on device.
* `EOVERFLOW` (75), Value too large.
+* `ENOTSUP` (95), Operation not supported.
* `ESHUTDOWN` (108), Server is in the process of being shut down.
The server SHOULD return `ENOSPC` if it receives a write request
@@ -2125,6 +2163,10 @@ request is not aligned to advertised minimum block sizes. Finally, it
SHOULD return `EPERM` if it receives a write or trim request on a
read-only export.
+The server SHOULD NOT return `ENOTSUP` except as documented in
+response to `NBD_CMD_WRITE_ZEROES` when `NBD_CMD_FLAG_FAST_ZERO` is
+supported.
+
The server SHOULD return `EINVAL` if it receives an unknown command.
The server SHOULD return `EINVAL` if it receives an unknown command flag. It
--
2.20.1
5 years, 7 months
small question regarding ovirt
by Hetz Ben Hamo
Hi,
Small questoin: when running the P2v hard disk image, and I want to convert
a phyical machine to oVirt, to which machine do I connect when the GUI
starts? one of the nodes or the hosted engine? (i'm not talking about the
URL).
Thanks
5 years, 7 months
[PATCH v2 0/3] v2v: add -o json output mode
by Pino Toscano
This series adds a new output mode for virt-v2v, called -o json.
It produces local files, just like -o local, although the metadata
produced is a JSON file with data that v2v collected in the conversion
process. This can be useful for converting to unsupported destinations,
still based on QEMU/KVM.
In addition to a simple different metadata, it offers a way to relocate
the disks, with %{...}-like variables (only 3 added ATM, more can be
added) to change their paths depending on data of the guest/disks.
Changes from v1:
- remove extra code for optional named parameters in pcre_tests.ml
- allow %-escaping of variables in Var_expander
Pino Toscano (3):
common/mlpcre: add offset flag for PCRE.matches
v2v: add Var_expander
v2v: add -o json output mode
.gitignore | 1 +
common/mlpcre/PCRE.ml | 2 +-
common/mlpcre/PCRE.mli | 5 +-
common/mlpcre/pcre-c.c | 16 +-
common/mlpcre/pcre_tests.ml | 11 +-
v2v/Makefile.am | 36 +++-
v2v/cmdline.ml | 29 +++
v2v/create_json.ml | 348 ++++++++++++++++++++++++++++++++++
v2v/create_json.mli | 29 +++
v2v/dummy.c | 2 +
v2v/output_json.ml | 116 ++++++++++++
v2v/output_json.mli | 31 +++
v2v/var_expander.ml | 72 +++++++
v2v/var_expander.mli | 82 ++++++++
v2v/var_expander_tests.ml | 113 +++++++++++
v2v/virt-v2v-output-local.pod | 55 ++++++
v2v/virt-v2v.pod | 15 +-
17 files changed, 951 insertions(+), 12 deletions(-)
create mode 100644 v2v/create_json.ml
create mode 100644 v2v/create_json.mli
create mode 100644 v2v/dummy.c
create mode 100644 v2v/output_json.ml
create mode 100644 v2v/output_json.mli
create mode 100644 v2v/var_expander.ml
create mode 100644 v2v/var_expander.mli
create mode 100644 v2v/var_expander_tests.ml
--
2.20.1
5 years, 7 months
