Splitting up virt-v2v
by Richard W.M. Jones
For a long time I've wanted to split up virt-v2v into smaller
components to make it easier to consume. It's never been clear how to
do this, but I think I have a workable plan now, described in this email.
----------------------------------------------------------------------
First, the AIMS, which are:
(a) Preserve current functionality, including copying conversion,
in-place conversion, and the virt-v2v command line.
(b) Allow warm migration to use virt-v2v without requiring the
"--debug-overlays hack".
(c) Allow threads, multi-conn, and parallel copying of guest disks, all
for better copying performance.
(d) Allow an alternate supervisor to convert and copy many guests in
parallel, given that the supervisor has a global view of the
system/network (I'm not intending to implement this, only to make
it possible).
(e) Better progress bars.
(f) Better logging.
(g) Reuse as much existing code as possible. This is NOT a rewrite!
----------------------------------------------------------------------
Here's my PLAN:
/usr/bin/virt-v2v still exists, but it's now a supervisor program
(possibly even a shell script) that runs the steps below:
(1) Set up the input side by running "helper-v2v-input-<type>". For
all input types this creates a temporary directory containing:
/tmp/XXXXXX/in1 NBD endpoints overlaying the source disk(s)
/tmp/XXXXXX/in2 (these are actually Unix domain sockets)
/tmp/XXXXXX/in3
/tmp/XXXXXX/metadata.in Metadata parsed from the source.
Currently for most inputs we have a running nbdkit process for
each source disk, and we'd do the same here, except we add
nbdkit-cow-filter on top so that the source disk is protected from
being modified. Another small difference is that for -i disk
(local input) we would need an active nbdkit process on top of the
disk, whereas currently we set the disk as a qcow2 backing file.
(2) Perform the conversion by running "helper-v2v-convert". This does
the conversion and sparsification. It writes directly to the NBD
endpoints (in*) above. The writes are stored in the COW overlay
so the source disk is not modified.
Conversion will also create an output metadata file:
/tmp/XXXXXX/metadata.out Target metadata
Exact format of the metadata files is to be decided, but some kind
of not-quite-libvirt-XML may be suitable. It's also not clear if
the metadata format is an internal detail of virt-v2v, or if we
document it as a stable API.
(3) Set up the output side by running "helper-v2v-output-<type>
setup". This will read the output metadata and do whatever is
needed to set up the empty output disks (perhaps by creating a
guest on the target, but also this could be done in step (5)
below).
This will create:
/tmp/XXXXXX/out1 NBD endpoints overlaying the target disk(s)
/tmp/XXXXXX/out2 (these are actually Unix domain sockets)
/tmp/XXXXXX/out3
(4) Do the copy. By default this will run either nbdcopy or qemu-img
convert from in* -> out*.
Copying could be done in parallel, currently it is done serially.
(5) Finalize the output by running "helper-v2v-output-<type> final".
This might create the target guest and whatever else is needed.
(6) Kill the NBD servers and clean up the temporary directory.
----------------------------------------------------------------------
Let's see how this plan matches the aims.
Aim (a):
Copying conversion works as outlined above. In-place conversion
works by placing an NBD server on top of the files you want to
convert and running helper-v2v-convert (virt-v2v --in-place would
also still work for backwards compat).
Aim (b):
Warm migration: Should be fairly clear this can work in the same way
as in-place conversion, but I'll discuss this further with Martin K
and Tomas to make sure I'm not missing anything.
Aims (c), (d):
Threads etc for performance: Although I don't plan to implement
this, it's clear that an alternate supervisor program could improve
performance here by either doing copies of a single guest / multiple
disks in parallel, but even better by having a global view of the
system and doing copies of multiple guests' disks in parallel.
This is outside the scope of the virt-v2v project, but in scope for
something like MTV.
Aim (e):
Better progress bars: nbdcopy should have support for
machine-readable progress bars, once I push the changes. It will
mean no more need to parse debug logs.
Aim (f):
Better logging: I hope we can log each step separately.
A custom supervisor program would also be able to tell which
particular step failed (eg. did it fail in conversion? did it fail
copying a disk and which one?)
Aim (g):
This works by splitting up the existing v2v code base into separate
binaries. It is already broadly structured (internally) like this.
So it's not a rewrite, it's a big refactoring.
However I'd probably write a new virt-v2v supervisor binary, because
the existing command line parsing code is extremely complex.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines. Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top
3 years, 9 months
[PATCH nbdcopy] copy: Implement extent metadata for efficient copying.
by Richard W.M. Jones
This implements these interconnected options:
--allocated
--destination-is-zero (alias: --target-is-zero)
--no-extents
---
TODO | 6 +-
copy/Makefile.am | 7 +
copy/copy-sparse-allocated.sh | 92 ++++++++++++++
copy/copy-sparse-no-extents.sh | 92 ++++++++++++++
copy/copy-sparse.sh | 97 ++++++++++++++
copy/file-ops.c | 181 ++++++++++++++++++++++++++
copy/main.c | 107 ++++++++++++++--
copy/multi-thread-copying.c | 226 ++++++++++++++++++++++++---------
copy/nbd-ops.c | 176 +++++++++++++++++++++++++
copy/nbdcopy.h | 50 ++++++++
copy/nbdcopy.pod | 32 ++++-
copy/pipe-ops.c | 30 ++++-
12 files changed, 1015 insertions(+), 81 deletions(-)
diff --git a/TODO b/TODO
index 9e5c821..8c0402e 100644
--- a/TODO
+++ b/TODO
@@ -30,9 +30,9 @@ Performance: Chart it over various buffer sizes and threads, as that
Examine other fuzzers: https://gitlab.com/akihe/radamsa
nbdcopy:
- - Properly handle extents/sparseness in input and output.
- - Write zeroes efficiently.
- - Detect zeroes (optionally) and turn into sparseness.
+ - --synchronous mode does not yet support extents.
+ - Detect zeroes (optionally) and turn into sparseness
+ (like qemu-img convert -S).
- Progress bar: allow it to be written to a file descriptor
and/or written in a machine-consumable format.
- Minimum/preferred/maximum block size.
diff --git a/copy/Makefile.am b/copy/Makefile.am
index 8f2d168..cfbc386 100644
--- a/copy/Makefile.am
+++ b/copy/Makefile.am
@@ -26,6 +26,9 @@ EXTRA_DIST = \
copy-nbd-to-small-block-error.sh \
copy-nbd-to-small-nbd-error.sh \
copy-nbd-to-stdout.sh \
+ copy-sparse.sh \
+ copy-sparse-allocated.sh \
+ copy-sparse-no-extents.sh \
copy-stdin-to-nbd.sh \
nbdcopy.pod \
$(NULL)
@@ -46,6 +49,7 @@ nbdcopy_SOURCES = \
$(NULL)
nbdcopy_CPPFLAGS = \
-I$(top_srcdir)/include \
+ -I$(top_srcdir)/common/include \
-I$(top_srcdir)/common/utils \
$(NULL)
nbdcopy_CFLAGS = \
@@ -88,6 +92,9 @@ TESTS += \
copy-nbd-to-small-nbd-error.sh \
copy-stdin-to-nbd.sh \
copy-nbd-to-stdout.sh \
+ copy-sparse.sh \
+ copy-sparse-allocated.sh \
+ copy-sparse-no-extents.sh \
$(ROOT_TESTS) \
$(NULL)
diff --git a/copy/copy-sparse-allocated.sh b/copy/copy-sparse-allocated.sh
new file mode 100755
index 0000000..203c3b9
--- /dev/null
+++ b/copy/copy-sparse-allocated.sh
@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+# nbd client library in userspace
+# Copyright (C) 2020 Red Hat Inc.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+# Adapted from copy-sparse.sh.
+#
+# This test depends on the nbdkit default sparse block size (32K).
+
+. ../tests/functions.sh
+
+set -e
+set -x
+
+requires nbdkit --version
+requires nbdkit --exit-with-parent --version
+requires nbdkit data --version
+requires nbdkit eval --version
+
+out=copy-sparse-allocated.out
+cleanup_fn rm -f $out
+
+$VG nbdcopy --allocated -- \
+ [ nbdkit --exit-with-parent data data='
+ 1
+ @1073741823 1
+ @4294967295 1
+ @4294967296 1
+ ' ] \
+ [ nbdkit --exit-with-parent eval \
+ get_size=' echo 7E ' \
+ pwrite=" echo \$@ >> $out " \
+ trim=" echo \$@ >> $out " \
+ zero=" echo \$@ >> $out " ]
+
+sort -o $out $out
+
+echo Output:
+cat $out
+
+if [ "$(cat $out)" != "pwrite 1 4294967296
+pwrite 32768 0
+pwrite 32768 1073709056
+pwrite 32768 4294934528
+zero 134184960 32768
+zero 134184960 4160749568
+zero 134184960 939524096
+zero 134217728 1073741824
+zero 134217728 1207959552
+zero 134217728 134217728
+zero 134217728 1342177280
+zero 134217728 1476395008
+zero 134217728 1610612736
+zero 134217728 1744830464
+zero 134217728 1879048192
+zero 134217728 2013265920
+zero 134217728 2147483648
+zero 134217728 2281701376
+zero 134217728 2415919104
+zero 134217728 2550136832
+zero 134217728 268435456
+zero 134217728 2684354560
+zero 134217728 2818572288
+zero 134217728 2952790016
+zero 134217728 3087007744
+zero 134217728 3221225472
+zero 134217728 3355443200
+zero 134217728 3489660928
+zero 134217728 3623878656
+zero 134217728 3758096384
+zero 134217728 3892314112
+zero 134217728 402653184
+zero 134217728 4026531840
+zero 134217728 536870912
+zero 134217728 671088640
+zero 134217728 805306368" ]; then
+ echo "$0: output does not match expected"
+ exit 1
+fi
diff --git a/copy/copy-sparse-no-extents.sh b/copy/copy-sparse-no-extents.sh
new file mode 100755
index 0000000..e976d55
--- /dev/null
+++ b/copy/copy-sparse-no-extents.sh
@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+# nbd client library in userspace
+# Copyright (C) 2020 Red Hat Inc.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+# Adapted from copy-sparse.sh
+#
+# This test depends on the nbdkit default sparse block size (32K).
+
+. ../tests/functions.sh
+
+set -e
+set -x
+
+# Skip this test under valgrind, it takes too long.
+if [ "x$LIBNBD_VALGRIND" = "x1" ]; then
+ echo "$0: test skipped under valgrind"
+ exit 77
+fi
+
+requires nbdkit --version
+requires nbdkit --exit-with-parent --version
+requires nbdkit data --version
+requires nbdkit eval --version
+
+out=copy-sparse-no-extents.out
+cleanup_fn rm -f $out
+
+$VG nbdcopy --no-extents -- \
+ [ nbdkit --exit-with-parent data data='
+ 1
+ @1073741823 1
+ ' ] \
+ [ nbdkit --exit-with-parent eval \
+ get_size=' echo 7E ' \
+ pwrite=" echo \$@ >> $out " \
+ trim=" echo \$@ >> $out " \
+ zero=" echo \$@ >> $out " ]
+
+sort -n -o $out $out
+
+echo Output:
+cat $out
+
+if [ "$(cat $out)" != "pwrite 33554432 0
+pwrite 33554432 100663296
+pwrite 33554432 1006632960
+pwrite 33554432 1040187392
+pwrite 33554432 134217728
+pwrite 33554432 167772160
+pwrite 33554432 201326592
+pwrite 33554432 234881024
+pwrite 33554432 268435456
+pwrite 33554432 301989888
+pwrite 33554432 33554432
+pwrite 33554432 335544320
+pwrite 33554432 369098752
+pwrite 33554432 402653184
+pwrite 33554432 436207616
+pwrite 33554432 469762048
+pwrite 33554432 503316480
+pwrite 33554432 536870912
+pwrite 33554432 570425344
+pwrite 33554432 603979776
+pwrite 33554432 637534208
+pwrite 33554432 67108864
+pwrite 33554432 671088640
+pwrite 33554432 704643072
+pwrite 33554432 738197504
+pwrite 33554432 771751936
+pwrite 33554432 805306368
+pwrite 33554432 838860800
+pwrite 33554432 872415232
+pwrite 33554432 905969664
+pwrite 33554432 939524096
+pwrite 33554432 973078528" ]; then
+ echo "$0: output does not match expected"
+ exit 1
+fi
diff --git a/copy/copy-sparse.sh b/copy/copy-sparse.sh
new file mode 100755
index 0000000..2fc4d9a
--- /dev/null
+++ b/copy/copy-sparse.sh
@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+# nbd client library in userspace
+# Copyright (C) 2020 Red Hat Inc.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+# This test depends on the nbdkit default sparse block size (32K).
+
+. ../tests/functions.sh
+
+set -e
+set -x
+
+requires nbdkit --version
+requires nbdkit --exit-with-parent --version
+requires nbdkit data --version
+requires nbdkit eval --version
+
+out=copy-sparse.out
+cleanup_fn rm -f $out
+
+# Copy from a sparse data disk to an nbdkit-eval-plugin instance which
+# is logging everything. This allows us to see exactly what nbdcopy
+# is writing, to ensure it is writing and trimming the target as
+# expected.
+$VG nbdcopy -- \
+ [ nbdkit --exit-with-parent data data='
+ 1
+ @1073741823 1
+ @4294967295 1
+ @4294967296 1
+ ' ] \
+ [ nbdkit --exit-with-parent eval \
+ get_size=' echo 7E ' \
+ pwrite=" echo \$@ >> $out " \
+ trim=" echo \$@ >> $out " \
+ zero=" echo \$@ >> $out " ]
+
+# Order of the output could vary because requests are sent in
+# parallel.
+sort -n -o $out $out
+
+echo Output:
+cat $out
+
+# Check the output matches expected.
+if [ "$(cat $out)" != "pwrite 1 4294967296
+pwrite 32768 0
+pwrite 32768 1073709056
+pwrite 32768 4294934528
+trim 134184960 32768
+trim 134184960 4160749568
+trim 134184960 939524096
+trim 134217728 1073741824
+trim 134217728 1207959552
+trim 134217728 134217728
+trim 134217728 1342177280
+trim 134217728 1476395008
+trim 134217728 1610612736
+trim 134217728 1744830464
+trim 134217728 1879048192
+trim 134217728 2013265920
+trim 134217728 2147483648
+trim 134217728 2281701376
+trim 134217728 2415919104
+trim 134217728 2550136832
+trim 134217728 268435456
+trim 134217728 2684354560
+trim 134217728 2818572288
+trim 134217728 2952790016
+trim 134217728 3087007744
+trim 134217728 3221225472
+trim 134217728 3355443200
+trim 134217728 3489660928
+trim 134217728 3623878656
+trim 134217728 3758096384
+trim 134217728 3892314112
+trim 134217728 402653184
+trim 134217728 4026531840
+trim 134217728 536870912
+trim 134217728 671088640
+trim 134217728 805306368" ]; then
+ echo "$0: output does not match expected"
+ exit 1
+fi
diff --git a/copy/file-ops.c b/copy/file-ops.c
index 9e94b30..cd19e81 100644
--- a/copy/file-ops.c
+++ b/copy/file-ops.c
@@ -24,7 +24,16 @@
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <pthread.h>
+
+#if defined (__linux__)
+#include <linux/fs.h> /* For BLKZEROOUT */
+#endif
+
+#include "isaligned.h"
#include "nbdcopy.h"
static size_t
@@ -74,6 +83,64 @@ file_synch_write (struct rw *rw,
}
}
+static bool
+file_synch_trim (struct rw *rw, uint64_t offset, uint64_t count)
+{
+ assert (rw->t == LOCAL);
+
+#ifdef FALLOC_FL_PUNCH_HOLE
+ int fd = rw->u.local.fd;
+ int r;
+
+ r = fallocate (fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ offset, count);
+ if (r == -1) {
+ perror ("fallocate: FALLOC_FL_PUNCH_HOLE");
+ exit (EXIT_FAILURE);
+ }
+ return true;
+#else /* !FALLOC_FL_PUNCH_HOLE */
+ return false;
+#endif
+}
+
+static bool
+file_synch_zero (struct rw *rw, uint64_t offset, uint64_t count)
+{
+ assert (rw->t == LOCAL);
+
+ if (S_ISREG (rw->u.local.stat.st_mode)) {
+#ifdef FALLOC_FL_ZERO_RANGE
+ int fd = rw->u.local.fd;
+ int r;
+
+ r = fallocate (fd, FALLOC_FL_ZERO_RANGE, offset, count);
+ if (r == -1) {
+ perror ("fallocate: FALLOC_FL_ZERO_RANGE");
+ exit (EXIT_FAILURE);
+ }
+ return true;
+#endif
+ }
+ else if (S_ISBLK (rw->u.local.stat.st_mode) &&
+ IS_ALIGNED (offset | count, rw->u.local.sector_size)) {
+#ifdef BLKZEROOUT
+ int fd = rw->u.local.fd;
+ int r;
+ uint64_t range[2] = {offset, count};
+
+ r = ioctl (fd, BLKZEROOUT, &range);
+ if (r == -1) {
+ perror ("ioctl: BLKZEROOUT");
+ exit (EXIT_FAILURE);
+ }
+ return true;
+#endif
+ }
+
+ return false;
+}
+
static void
file_asynch_read (struct rw *rw,
struct buffer *buffer,
@@ -104,9 +171,123 @@ file_asynch_write (struct rw *rw,
}
}
+static bool
+file_asynch_trim (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb)
+{
+ assert (rw->t == LOCAL);
+
+ if (!file_synch_trim (rw, buffer->offset, buffer->len))
+ return false;
+ errno = 0;
+ if (cb.callback (cb.user_data, &errno) == -1) {
+ perror (rw->name);
+ exit (EXIT_FAILURE);
+ }
+ return true;
+}
+
+static bool
+file_asynch_zero (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb)
+{
+ assert (rw->t == LOCAL);
+
+ if (!file_synch_zero (rw, buffer->offset, buffer->len))
+ return false;
+ errno = 0;
+ if (cb.callback (cb.user_data, &errno) == -1) {
+ perror (rw->name);
+ exit (EXIT_FAILURE);
+ }
+ return true;
+}
+
+static void
+file_get_extents (struct rw *rw, uintptr_t index,
+ uint64_t offset, uint64_t count,
+ extent_list *ret)
+{
+ assert (rw->t == LOCAL);
+
+ ret->size = 0;
+
+#ifdef SEEK_HOLE
+ static pthread_mutex_t lseek_lock = PTHREAD_MUTEX_INITIALIZER;
+
+ if (rw->u.local.seek_hole_supported) {
+ uint64_t end = offset + count;
+ int fd = rw->u.local.fd;
+ off_t pos;
+ struct extent e;
+
+ pthread_mutex_lock (&lseek_lock);
+
+ /* This loop is taken pretty much verbatim from nbdkit-file-plugin. */
+ do {
+ pos = lseek (fd, offset, SEEK_DATA);
+ if (pos == -1) {
+ if (errno == ENXIO)
+ pos = end;
+ else {
+ perror ("lseek: SEEK_DATA");
+ exit (EXIT_FAILURE);
+ }
+ }
+
+ /* We know there is a hole from offset to pos-1. */
+ if (pos > offset) {
+ e.offset = offset;
+ e.length = pos - offset;
+ e.hole = true;
+ if (extent_list_append (ret, e) == -1) {
+ perror ("realloc");
+ exit (EXIT_FAILURE);
+ }
+ }
+
+ offset = pos;
+ if (offset >= end)
+ break;
+
+ pos = lseek (fd, offset, SEEK_HOLE);
+ if (pos == -1) {
+ perror ("lseek: SEEK_HOLE");
+ exit (EXIT_FAILURE);
+ }
+
+ /* We know there is allocated data from offset to pos-1. */
+ if (pos > offset) {
+ e.offset = offset;
+ e.length = pos - offset;
+ e.hole = false;
+ if (extent_list_append (ret, e) == -1) {
+ perror ("realloc");
+ exit (EXIT_FAILURE);
+ }
+ }
+
+ offset = pos;
+ } while (offset < end);
+
+ pthread_mutex_unlock (&lseek_lock);
+ return;
+ }
+#endif
+
+ /* Otherwise return the default extent covering the whole range. */
+ default_get_extents (rw, index, offset, count, ret);
+}
+
+
struct rw_ops file_ops = {
.synch_read = file_synch_read,
.synch_write = file_synch_write,
+ .synch_trim = file_synch_trim,
+ .synch_zero = file_synch_zero,
.asynch_read = file_asynch_read,
.asynch_write = file_asynch_write,
+ .asynch_trim = file_asynch_trim,
+ .asynch_zero = file_asynch_zero,
+ .get_extents = file_get_extents,
};
diff --git a/copy/main.c b/copy/main.c
index 0b0589e..8187944 100644
--- a/copy/main.c
+++ b/copy/main.c
@@ -27,9 +27,11 @@
#include <limits.h>
#include <fcntl.h>
#include <unistd.h>
+#include <errno.h>
+#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
-#include <assert.h>
+#include <sys/ioctl.h>
#include <pthread.h>
@@ -37,7 +39,10 @@
#include "nbdcopy.h"
+bool allocated; /* --allocated flag */
unsigned connections = 4; /* --connections */
+bool destination_is_zero; /* --destination-is-zero flag */
+bool extents = true; /* ! --no-extents flag */
bool flush; /* --flush flag */
unsigned max_requests = 64; /* --requests */
bool progress; /* -p flag */
@@ -46,13 +51,14 @@ unsigned threads; /* --threads */
struct rw src, dst; /* The source and destination. */
static bool is_nbd_uri (const char *s);
+static bool seek_hole_supported (int fd);
static int open_local (const char *prog,
const char *filename, bool writing, struct rw *rw);
static void open_nbd_uri (const char *prog,
- const char *uri, struct rw *rw);
+ const char *uri, bool writing, struct rw *rw);
static void open_nbd_subprocess (const char *prog,
const char **argv, size_t argc,
- struct rw *rw);
+ bool writing, struct rw *rw);
static void __attribute__((noreturn))
usage (FILE *fp, int exitcode)
@@ -85,19 +91,26 @@ main (int argc, char *argv[])
HELP_OPTION = CHAR_MAX + 1,
LONG_OPTIONS,
SHORT_OPTIONS,
+ ALLOCATED_OPTION,
+ DESTINATION_IS_ZERO_OPTION,
FLUSH_OPTION,
+ NO_EXTENTS_OPTION,
SYNCHRONOUS_OPTION,
};
const char *short_options = "C:pR:T:V";
const struct option long_options[] = {
{ "help", no_argument, NULL, HELP_OPTION },
{ "long-options", no_argument, NULL, LONG_OPTIONS },
+ { "allocated", no_argument, NULL, ALLOCATED_OPTION },
{ "connections", required_argument, NULL, 'C' },
+ { "destination-is-zero",no_argument, NULL, DESTINATION_IS_ZERO_OPTION },
{ "flush", no_argument, NULL, FLUSH_OPTION },
+ { "no-extents", no_argument, NULL, NO_EXTENTS_OPTION },
{ "progress", no_argument, NULL, 'p' },
{ "requests", required_argument, NULL, 'R' },
{ "short-options", no_argument, NULL, SHORT_OPTIONS },
{ "synchronous", no_argument, NULL, SYNCHRONOUS_OPTION },
+ { "target-is-zero", no_argument, NULL, DESTINATION_IS_ZERO_OPTION },
{ "threads", required_argument, NULL, 'T' },
{ "version", no_argument, NULL, 'V' },
{ NULL }
@@ -129,10 +142,22 @@ main (int argc, char *argv[])
}
exit (EXIT_SUCCESS);
+ case ALLOCATED_OPTION:
+ allocated = true;
+ break;
+
+ case DESTINATION_IS_ZERO_OPTION:
+ destination_is_zero = true;
+ break;
+
case FLUSH_OPTION:
flush = true;
break;
+ case NO_EXTENTS_OPTION:
+ extents = false;
+ break;
+
case SYNCHRONOUS_OPTION:
synchronous = true;
break;
@@ -191,7 +216,8 @@ main (int argc, char *argv[])
src.t = NBD;
src.name = argv[optind+1];
open_nbd_subprocess (argv[0],
- (const char **) &argv[optind+1], i-optind-1, &src);
+ (const char **) &argv[optind+1], i-optind-1,
+ false, &src);
optind = i+1;
}
else { /* Source is not [...]. */
@@ -201,7 +227,7 @@ main (int argc, char *argv[])
if (src.t == LOCAL)
src.u.local.fd = open_local (argv[0], src.name, false, &src);
else
- open_nbd_uri (argv[0], src.name, &src);
+ open_nbd_uri (argv[0], src.name, false, &src);
}
if (optind >= argc)
@@ -218,7 +244,8 @@ main (int argc, char *argv[])
dst.t = NBD;
dst.name = argv[optind+1];
open_nbd_subprocess (argv[0],
- (const char **) &argv[optind+1], i-optind-1, &dst);
+ (const char **) &argv[optind+1], i-optind-1,
+ true, &dst);
optind = i+1;
}
else { /* Destination is not [...] */
@@ -228,7 +255,7 @@ main (int argc, char *argv[])
if (dst.t == LOCAL)
dst.u.local.fd = open_local (argv[0], dst.name, true /* writing */, &dst);
else {
- open_nbd_uri (argv[0], dst.name, &dst);
+ open_nbd_uri (argv[0], dst.name, true, &dst);
/* Obviously this is not going to work if the server is
* advertising read-only, so fail early with a nice error message.
@@ -318,6 +345,7 @@ main (int argc, char *argv[])
perror ("truncate");
exit (EXIT_FAILURE);
}
+ destination_is_zero = true;
}
else if (dst.t == NBD) {
dst.size = nbd_get_size (dst.u.nbd.ptr[0]);
@@ -345,16 +373,23 @@ main (int argc, char *argv[])
if (src.t == NBD) {
for (i = 1; i < connections; ++i)
- open_nbd_uri (argv[0], src.name, &src);
+ open_nbd_uri (argv[0], src.name, false, &src);
assert (src.u.nbd.size == connections);
}
if (dst.t == NBD) {
for (i = 1; i < connections; ++i)
- open_nbd_uri (argv[0], dst.name, &dst);
+ open_nbd_uri (argv[0], dst.name, true, &dst);
assert (dst.u.nbd.size == connections);
}
}
+ /* If the source is NBD and we couldn't negotiate meta
+ * base:allocation then turn off extents.
+ */
+ if (src.t == NBD &&
+ !nbd_can_meta_context (src.u.nbd.ptr[0], "base:allocation"))
+ extents = false;
+
/* Start copying. */
if (synchronous)
synch_copying ();
@@ -483,11 +518,18 @@ open_local (const char *prog,
perror ("lseek");
exit (EXIT_FAILURE);
}
+ rw->u.local.seek_hole_supported = seek_hole_supported (fd);
+ rw->u.local.sector_size = 4096;
+#ifdef BLKSSZGET
+ if (ioctl (fd, BLKSSZGET, &rw->u.local.sector_size))
+ fprintf (stderr, "warning: cannot get sector size: %s: %m", rw->name);
+#endif
}
else if (S_ISREG (rw->u.local.stat.st_mode)) {
/* Regular file. */
rw->ops = &file_ops;
rw->size = rw->u.local.stat.st_size;
+ rw->u.local.seek_hole_supported = seek_hole_supported (fd);
}
else {
/* Probably stdin/stdout, a pipe or a socket. Set size == -1
@@ -496,14 +538,26 @@ open_local (const char *prog,
synchronous = true;
rw->ops = &pipe_ops;
rw->size = -1;
+ rw->u.local.seek_hole_supported = false;
}
return fd;
}
+static bool
+seek_hole_supported (int fd)
+{
+#ifndef SEEK_HOLE
+ return false;
+#else
+ off_t r = lseek (fd, 0, SEEK_HOLE);
+ return r >= 0;
+#endif
+}
+
static void
open_nbd_uri (const char *prog,
- const char *uri, struct rw *rw)
+ const char *uri, bool writing, struct rw *rw)
{
struct nbd_handle *nbd;
@@ -514,6 +568,11 @@ open_nbd_uri (const char *prog,
exit (EXIT_FAILURE);
}
nbd_set_uri_allow_local_file (nbd, true); /* Allow ?tls-psk-file. */
+ if (extents && !writing &&
+ nbd_add_meta_context (nbd, "base:allocation") == -1) {
+ fprintf (stderr, "%s: %s\n", prog, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
if (handles_append (&rw->u.nbd, nbd) == -1) {
perror ("realloc");
@@ -531,7 +590,7 @@ DEFINE_VECTOR_TYPE (const_string_vector, const char *);
static void
open_nbd_subprocess (const char *prog,
const char **argv, size_t argc,
- struct rw *rw)
+ bool writing, struct rw *rw)
{
struct nbd_handle *nbd;
const_string_vector copy = empty_vector;
@@ -543,6 +602,11 @@ open_nbd_subprocess (const char *prog,
fprintf (stderr, "%s: %s\n", prog, nbd_get_error ());
exit (EXIT_FAILURE);
}
+ if (extents && !writing &&
+ nbd_add_meta_context (nbd, "base:allocation") == -1) {
+ fprintf (stderr, "%s: %s\n", prog, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
if (handles_append (&rw->u.nbd, nbd) == -1) {
memory_error:
@@ -565,3 +629,24 @@ open_nbd_subprocess (const char *prog,
free (copy.ptr);
}
+
+/* Default implementation of rw->ops->get_extents for backends which
+ * don't/can't support extents. Also used for the --no-extents case.
+ */
+void
+default_get_extents (struct rw *rw, uintptr_t index,
+ uint64_t offset, uint64_t count,
+ extent_list *ret)
+{
+ struct extent e;
+
+ ret->size = 0;
+
+ e.offset = offset;
+ e.length = count;
+ e.hole = false;
+ if (extent_list_append (ret, e) == -1) {
+ perror ("realloc");
+ exit (EXIT_FAILURE);
+ }
+}
diff --git a/copy/multi-thread-copying.c b/copy/multi-thread-copying.c
index 3805daf..8081bb1 100644
--- a/copy/multi-thread-copying.c
+++ b/copy/multi-thread-copying.c
@@ -27,6 +27,7 @@
#include <poll.h>
#include <errno.h>
#include <assert.h>
+#include <sys/stat.h>
#include <pthread.h>
@@ -122,12 +123,14 @@ multi_thread_copying (void)
free (workers);
}
+static void wait_for_request_slots (uintptr_t index);
static unsigned in_flight (struct nbd_handle *src_nbd,
struct nbd_handle *dst_nbd);
static void poll_both_ends (struct nbd_handle *src_nbd,
struct nbd_handle *dst_nbd);
static int finished_read (void *vp, int *error);
-static int finished_write (void *vp, int *error);
+static int free_buffer (void *vp, int *error);
+static void fill_dst_range_with_zeroes (struct buffer *buffer);
/* There are 'threads' worker threads, each copying work ranges from
* src to dst until there are no more work ranges.
@@ -138,13 +141,7 @@ worker_thread (void *indexp)
uintptr_t index = (uintptr_t) indexp;
uint64_t offset, count;
struct nbd_handle *src_nbd, *dst_nbd;
- bool done = false;
-
- if (! get_next_offset (&offset, &count))
- /* No work to do, return immediately. Can happen for files which
- * are smaller than THREAD_WORK_SIZE where multi-conn is enabled.
- */
- return NULL;
+ extent_list exts = empty_vector;
/* In the case where src or dst is NBD, use
* {src|dst}.u.nbd.ptr[index] so that each thread is connected to
@@ -161,54 +158,77 @@ worker_thread (void *indexp)
else
dst_nbd = NULL;
- while (!done) {
- struct buffer *buffer;
- char *data;
- size_t len;
-
- if (count == 0) {
- /* Get another work range. */
- done = ! get_next_offset (&offset, &count);
- if (done) break;
- assert (0 < count && count <= THREAD_WORK_SIZE);
- }
-
- /* If the number of requests in flight exceeds the limit, poll
- * waiting for at least one request to finish. This enforces the
- * user --requests option.
- */
- while (in_flight (src_nbd, dst_nbd) >= max_requests)
- poll_both_ends (src_nbd, dst_nbd);
-
- /* Create a new buffer. This will be freed in a callback handler. */
- len = count;
- if (len > MAX_REQUEST_SIZE)
- len = MAX_REQUEST_SIZE;
- data = malloc (len);
- if (data == NULL) {
- perror ("malloc");
- exit (EXIT_FAILURE);
- }
- buffer = malloc (sizeof *buffer);
- if (buffer == NULL) {
- perror ("malloc");
- exit (EXIT_FAILURE);
- }
- buffer->offset = offset;
- buffer->len = len;
- buffer->data = data;
- buffer->free_data = free;
- buffer->index = index;
-
- /* Begin the asynch read operation. */
- src.ops->asynch_read (&src, buffer,
- (nbd_completion_callback) {
- .callback = finished_read,
- .user_data = buffer,
- });
-
- offset += len;
- count -= len;
+ while (get_next_offset (&offset, &count)) {
+ size_t i;
+
+ assert (0 < count && count <= THREAD_WORK_SIZE);
+ if (extents)
+ src.ops->get_extents (&src, index, offset, count, &exts);
+ else
+ default_get_extents (&src, index, offset, count, &exts);
+
+ for (i = 0; i < exts.size; ++i) {
+ struct buffer *buffer;
+ char *data;
+ size_t len;
+
+ if (exts.ptr[i].hole) {
+ /* The source is a hole so we can proceed directly to
+ * skipping, trimming or writing zeroes at the destination.
+ */
+ buffer = calloc (1, sizeof *buffer);
+ if (buffer == NULL) {
+ perror ("malloc");
+ exit (EXIT_FAILURE);
+ }
+ buffer->offset = exts.ptr[i].offset;
+ buffer->len = exts.ptr[i].length;
+ buffer->index = index;
+ fill_dst_range_with_zeroes (buffer);
+ }
+
+ else /* data */ {
+ /* As the extent might be larger than permitted for a single
+ * command, we may have to split this into multiple read
+ * requests.
+ */
+ while (exts.ptr[i].length > 0) {
+ len = exts.ptr[i].length;
+ if (len > MAX_REQUEST_SIZE)
+ len = MAX_REQUEST_SIZE;
+ data = malloc (len);
+ if (data == NULL) {
+ perror ("malloc");
+ exit (EXIT_FAILURE);
+ }
+ buffer = calloc (1, sizeof *buffer);
+ if (buffer == NULL) {
+ perror ("malloc");
+ exit (EXIT_FAILURE);
+ }
+ buffer->offset = exts.ptr[i].offset;
+ buffer->len = len;
+ buffer->data = data;
+ buffer->free_data = free;
+ buffer->index = index;
+
+ wait_for_request_slots (index);
+
+ /* Begin the asynch read operation. */
+ src.ops->asynch_read (&src, buffer,
+ (nbd_completion_callback) {
+ .callback = finished_read,
+ .user_data = buffer,
+ });
+
+ exts.ptr[i].offset += len;
+ exts.ptr[i].length -= len;
+ }
+ }
+
+ offset += count;
+ count = 0;
+ } /* for extents */
}
/* Wait for in flight NBD requests to finish. */
@@ -218,14 +238,37 @@ worker_thread (void *indexp)
if (progress)
progress_bar (1, 1);
+ free (exts.ptr);
return NULL;
}
+/* If the number of requests in flight exceeds the limit, poll
+ * waiting for at least one request to finish. This enforces
+ * the user --requests option.
+ */
+static void
+wait_for_request_slots (uintptr_t index)
+{
+ struct nbd_handle *src_nbd, *dst_nbd;
+
+ if (src.t == NBD)
+ src_nbd = src.u.nbd.ptr[index];
+ else
+ src_nbd = NULL;
+ if (dst.t == NBD)
+ dst_nbd = dst.u.nbd.ptr[index];
+ else
+ dst_nbd = NULL;
+
+ while (in_flight (src_nbd, dst_nbd) >= max_requests)
+ poll_both_ends (src_nbd, dst_nbd);
+}
+
/* Count the number of NBD commands in flight. Since the commands are
* auto-retired in the callbacks we don't need to count "done"
* commands.
*/
-static inline unsigned
+static unsigned
in_flight (struct nbd_handle *src_nbd, struct nbd_handle *dst_nbd)
{
return
@@ -335,18 +378,79 @@ finished_read (void *vp, int *error)
dst.ops->asynch_write (&dst, buffer,
(nbd_completion_callback) {
- .callback = finished_write,
+ .callback = free_buffer,
.user_data = buffer,
});
return 1; /* auto-retires the command */
}
-/* Callback called when dst has finished one write command. We can
- * now free the buffer.
+/* Fill a range in dst with zeroes. This is called from the copying
+ * loop when we see a hole in the source. Depending on the command
+ * line flags this could mean:
+ *
+ * --destination-is-zero:
+ * do nothing
+ *
+ * --allocated: we must write zeroes either using an efficient
+ * zeroing command or writing a buffer of zeroes
+ *
+ * (neither flag) try trimming if supported, else write zeroes
+ * as above
+ *
+ * This takes over ownership of the buffer and frees it eventually.
*/
+static void
+fill_dst_range_with_zeroes (struct buffer *buffer)
+{
+ char *data;
+
+ if (destination_is_zero)
+ goto free_and_return;
+
+ if (!allocated) {
+ /* Try trimming. */
+ wait_for_request_slots (buffer->index);
+ if (dst.ops->asynch_trim (&dst, buffer,
+ (nbd_completion_callback) {
+ .callback = free_buffer,
+ .user_data = buffer,
+ }))
+ return;
+ }
+
+ /* Try efficient zeroing. */
+ wait_for_request_slots (buffer->index);
+ if (dst.ops->asynch_zero (&dst, buffer,
+ (nbd_completion_callback) {
+ .callback = free_buffer,
+ .user_data = buffer,
+ }))
+ return;
+
+ /* Fall back to loop writing zeroes. This is going to be slow
+ * anyway, so do it synchronously. XXX
+ */
+ data = calloc (1, BUFSIZ);
+ if (!data) {
+ perror ("calloc");
+ exit (EXIT_FAILURE);
+ }
+ while (buffer->len > 0) {
+ size_t len = buffer->len > BUFSIZ ? BUFSIZ : buffer->len;
+
+ dst.ops->synch_write (&dst, data, len, buffer->offset);
+ buffer->len -= len;
+ buffer->offset += len;
+ }
+ free (data);
+
+ free_and_return:
+ free_buffer (buffer, &errno);
+}
+
static int
-finished_write (void *vp, int *error)
+free_buffer (void *vp, int *error)
{
struct buffer *buffer = vp;
diff --git a/copy/nbd-ops.c b/copy/nbd-ops.c
index 3ae01ad..6a8ac95 100644
--- a/copy/nbd-ops.c
+++ b/copy/nbd-ops.c
@@ -57,6 +57,37 @@ nbd_synch_write (struct rw *rw,
}
}
+static bool
+nbd_synch_trim (struct rw *rw, uint64_t offset, uint64_t count)
+{
+ assert (rw->t == NBD);
+
+ if (nbd_can_trim (rw->u.nbd.ptr[0]) == 0)
+ return false;
+
+ if (nbd_trim (rw->u.nbd.ptr[0], count, offset, 0) == -1) {
+ fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
+ return true;
+}
+
+static bool
+nbd_synch_zero (struct rw *rw, uint64_t offset, uint64_t count)
+{
+ assert (rw->t == NBD);
+
+ if (nbd_can_zero (rw->u.nbd.ptr[0]) == 0)
+ return false;
+
+ if (nbd_zero (rw->u.nbd.ptr[0],
+ count, offset, LIBNBD_CMD_FLAG_NO_HOLE) == -1) {
+ fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
+ return true;
+}
+
static void
nbd_asynch_read (struct rw *rw,
struct buffer *buffer,
@@ -87,9 +118,154 @@ nbd_asynch_write (struct rw *rw,
}
}
+static bool
+nbd_asynch_trim (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb)
+{
+ assert (rw->t == NBD);
+
+ if (nbd_can_trim (rw->u.nbd.ptr[0]) == 0)
+ return false;
+
+ if (nbd_aio_trim (rw->u.nbd.ptr[buffer->index],
+ buffer->len, buffer->offset,
+ cb, 0) == -1) {
+ fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
+ return true;
+}
+
+static bool
+nbd_asynch_zero (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb)
+{
+ assert (rw->t == NBD);
+
+ if (nbd_can_zero (rw->u.nbd.ptr[0]) == 0)
+ return false;
+
+ if (nbd_aio_zero (rw->u.nbd.ptr[buffer->index],
+ buffer->len, buffer->offset,
+ cb, LIBNBD_CMD_FLAG_NO_HOLE) == -1) {
+ fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
+ return true;
+}
+
+static int
+add_extent (void *vp, const char *metacontext,
+ uint64_t offset, uint32_t *entries, size_t nr_entries,
+ int *error)
+{
+ extent_list *ret = vp;
+ size_t i;
+
+ if (strcmp (metacontext, "base:allocation") != 0)
+ return 0;
+
+ for (i = 0; i < nr_entries; i += 2) {
+ struct extent e;
+
+ e.offset = offset;
+ e.length = entries[i];
+ /* Note we deliberately don't care about the ZERO flag. */
+ e.hole = (entries[i+1] & LIBNBD_STATE_HOLE) != 0;
+ if (extent_list_append (ret, e) == -1) {
+ perror ("realloc");
+ exit (EXIT_FAILURE);
+ }
+
+ offset += entries[i];
+ }
+
+ return 0;
+}
+
+/* This is done synchronously, but that's fine because commands from
+ * the previous work range in flight continue to run, it's difficult
+ * to (sanely) start new work until we have the full list of extents,
+ * and in almost every case the remote NBD server can answer our
+ * request for extents in a single round trip.
+ */
+static void
+nbd_get_extents (struct rw *rw, uintptr_t index,
+ uint64_t offset, uint64_t count,
+ extent_list *ret)
+{
+ extent_list exts = empty_vector;
+ struct nbd_handle *nbd;
+
+ assert (rw->t == NBD);
+ nbd = rw->u.nbd.ptr[index];
+
+ ret->size = 0;
+
+ while (count > 0) {
+ size_t i;
+
+ exts.size = 0;
+ if (nbd_block_status (nbd, count, offset,
+ (nbd_extent_callback) {
+ .user_data = &exts,
+ .callback = add_extent
+ }, 0) == -1) {
+ /* XXX We could call default_get_extents, but unclear if it's
+ * the right thing to do if the server is returning errors.
+ */
+ fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
+ exit (EXIT_FAILURE);
+ }
+
+ /* The server should always make progress. */
+ if (exts.size == 0) {
+ fprintf (stderr, "%s: NBD server is broken: it is not returning extent information.\nTry nbdcopy --no-extents as a workaround.\n",
+ rw->name);
+ exit (EXIT_FAILURE);
+ }
+
+ /* Copy the extents returned into the final list (ret). This is
+ * complicated because the extents returned by the server may
+ * begin earlier and begin or end later than the requested size.
+ */
+ for (i = 0; i < exts.size; ++i) {
+ uint64_t d;
+
+ if (exts.ptr[i].offset + exts.ptr[i].length <= offset)
+ continue;
+ if (exts.ptr[i].offset < offset) {
+ d = offset - exts.ptr[i].offset;
+ exts.ptr[i].offset += d;
+ exts.ptr[i].length -= d;
+ assert (exts.ptr[i].offset == offset);
+ }
+ if (exts.ptr[i].offset + exts.ptr[i].length > offset + count) {
+ d = offset + count - exts.ptr[i].offset - exts.ptr[i].length;
+ exts.ptr[i].length -= d;
+ assert (exts.ptr[i].length == offset + count);
+ }
+ if (extent_list_append (ret, exts.ptr[i]) == -1) {
+ perror ("realloc");
+ exit (EXIT_FAILURE);
+ }
+
+ offset += exts.ptr[i].length;
+ count -= exts.ptr[i].length;
+ }
+ }
+
+ free (exts.ptr);
+}
+
struct rw_ops nbd_ops = {
.synch_read = nbd_synch_read,
.synch_write = nbd_synch_write,
+ .synch_trim = nbd_synch_trim,
+ .synch_zero = nbd_synch_zero,
.asynch_read = nbd_asynch_read,
.asynch_write = nbd_asynch_write,
+ .asynch_trim = nbd_asynch_trim,
+ .asynch_zero = nbd_asynch_zero,
+ .get_extents = nbd_get_extents,
};
diff --git a/copy/nbdcopy.h b/copy/nbdcopy.h
index 9e4fc19..d74abad 100644
--- a/copy/nbdcopy.h
+++ b/copy/nbdcopy.h
@@ -47,6 +47,8 @@ struct rw {
struct { /* For LOCAL. */
int fd;
struct stat stat;
+ bool seek_hole_supported;
+ int sector_size;
} local;
handles nbd; /* For NBD, one handle per connection. */
} u;
@@ -63,6 +65,14 @@ struct buffer {
uintptr_t index; /* Thread number. */
};
+/* List of extents for rw->ops->get_extents. */
+struct extent {
+ uint64_t offset;
+ uint64_t length;
+ bool hole;
+};
+DEFINE_VECTOR_TYPE(extent_list, struct extent);
+
/* The operations struct hides some of the differences between local
* file, NBD and pipes from the copying code.
*
@@ -80,6 +90,16 @@ struct rw_ops {
void (*synch_write) (struct rw *rw,
const void *data, size_t len, uint64_t offset);
+ /* Synchronously trim. buffer->data is not used. If not possible,
+ * returns false.
+ */
+ bool (*synch_trim) (struct rw *rw, uint64_t offset, uint64_t count);
+
+ /* Synchronously zero. buffer->data is not used. If not possible,
+ * returns false.
+ */
+ bool (*synch_zero) (struct rw *rw, uint64_t offset, uint64_t count);
+
/* Asynchronous I/O operations. These start the operation and call
* 'cb' on completion.
*
@@ -95,12 +115,42 @@ struct rw_ops {
void (*asynch_write) (struct rw *rw,
struct buffer *buffer,
nbd_completion_callback cb);
+
+ /* Asynchronously trim. buffer->data is not used. If not possible,
+ * returns false.
+ */
+ bool (*asynch_trim) (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb);
+
+ /* Asynchronously zero. buffer->data is not used. If not possible,
+ * returns false.
+ */
+ bool (*asynch_zero) (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb);
+
+ /* Read base:allocation extents metadata for a region of the source.
+ * For local files the same information is read from the kernel.
+ *
+ * Note that qemu-img fetches extents for the entire disk up front,
+ * and we want to avoid doing that because it had very negative
+ * behaviour for certain sources (ie. VDDK).
+ */
+ void (*get_extents) (struct rw *rw, uintptr_t index,
+ uint64_t offset, uint64_t count,
+ extent_list *ret);
};
extern struct rw_ops file_ops;
extern struct rw_ops nbd_ops;
extern struct rw_ops pipe_ops;
+extern void default_get_extents (struct rw *rw, uintptr_t index,
+ uint64_t offset, uint64_t count,
+ extent_list *ret);
+
+extern bool allocated;
extern unsigned connections;
+extern bool destination_is_zero;
+extern bool extents;
extern bool flush;
extern unsigned max_requests;
extern bool progress;
diff --git a/copy/nbdcopy.pod b/copy/nbdcopy.pod
index f654f65..5ff7434 100644
--- a/copy/nbdcopy.pod
+++ b/copy/nbdcopy.pod
@@ -4,7 +4,9 @@ nbdcopy - copy to and from an NBD server
=head1 SYNOPSIS
- nbdcopy [-C N|--connections=N] [--flush] [-p|--progress]
+ nbdcopy [--allocated] [-C N|--connections=N]
+ [--destination-is-zero|--target-is-zero]
+ [--flush] [--no-extents] [-p|--progress]
[-R N|--requests=N] [--synchronous]
[-T N|--threads=N]
SOURCE DESTINATION
@@ -74,6 +76,15 @@ formats use C<qemu-img convert>, see L<qemu-img(1)>.
Display brief command line help and exit.
+=item B<--allocated>
+
+Normally nbdcopy tries to create a sparse output (with holes), if the
+destination supports that. It does this in two ways: either using
+extent informtation from the source to copy holes (see
+I<--no-extents>), or by detecting runs of zeroes (see I<-S>). If you
+use I<--allocated> then nbdcopy creates a fully allocated, non-sparse
+output on the destination.
+
=item B<-C> N
=item B<--connections=>N
@@ -82,11 +93,30 @@ Set the maximum number of NBD connections ("multi-conn"). By default
nbdcopy will try to use multi-conn with up to 4 connections if the NBD
server supports it.
+=item B<--destination-is-zero>
+
+=item B<--target-is-zero>
+
+Assume the destination is already zeroed. This allows nbdcopy to skip
+copying blocks of zeroes from the source to the destination. This is
+not safe unless the destination device is already zeroed.
+(I<--target-is-zero> is provided for compatibility with
+L<qemu-img(1)>.)
+
=item B<--flush>
Flush writes to ensure that everything is written to persistent
storage before nbdcopy exits.
+=item B<--no-extents>
+
+Normally nbdcopy uses extent metadata to skip over parts of the source
+disk which contain holes. If you use this flag, nbdcopy ignores
+extent information and reads everything, which is usually slower. You
+might use this flag in two situations: the source NBD server has
+incorrect metadata information; or the source has very slow extent
+querying so it's faster to simply read all of the data.
+
=item B<-p>
=item B<--progress>
diff --git a/copy/pipe-ops.c b/copy/pipe-ops.c
index e10a31e..0788aae 100644
--- a/copy/pipe-ops.c
+++ b/copy/pipe-ops.c
@@ -61,6 +61,12 @@ pipe_synch_write (struct rw *rw,
}
}
+static bool
+pipe_synch_trim_zero (struct rw *rw, uint64_t offset, uint64_t count)
+{
+ return false; /* not supported by pipes */
+}
+
static void
pipe_asynch_read (struct rw *rw,
struct buffer *buffer,
@@ -77,16 +83,30 @@ pipe_asynch_write (struct rw *rw,
abort (); /* See comment below. */
}
+static bool
+pipe_asynch_trim_zero (struct rw *rw, struct buffer *buffer,
+ nbd_completion_callback cb)
+{
+ return false; /* not supported by pipes */
+}
+
struct rw_ops pipe_ops = {
.synch_read = pipe_synch_read,
.synch_write = pipe_synch_write,
+ .synch_trim = pipe_synch_trim_zero,
+ .synch_zero = pipe_synch_trim_zero,
- /* Asynch pipe operations are not defined. These should never be
- * called because pipes/streams/sockets force --synchronous.
- * Because calling a NULL pointer screws up the stack trace when
- * we're not using frame pointers, these are defined to functions
- * that call abort().
+ /* Asynch pipe read/write operations are not defined. These should
+ * never be called because pipes/streams/sockets force synchronous
+ * mode. Because calling a NULL pointer screws up the stack trace
+ * when we're not using frame pointers, these are defined to
+ * functions that call abort().
*/
.asynch_read = pipe_asynch_read,
.asynch_write = pipe_asynch_write,
+
+ .asynch_trim = pipe_asynch_trim_zero,
+ .asynch_zero = pipe_asynch_trim_zero,
+
+ .get_extents = default_get_extents,
};
--
2.29.0.rc2
3 years, 10 months
[v2v PATCH] windows: use libosinfo only for in-disk virtio-win
by Pino Toscano
Try to install the Windows drivers from virtio-win only in case it is
requested from a local directory (and not an ISO, or a block file).
---
v2v/windows_virtio.ml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/v2v/windows_virtio.ml b/v2v/windows_virtio.ml
index 4e00cd61..207fff2e 100644
--- a/v2v/windows_virtio.ml
+++ b/v2v/windows_virtio.ml
@@ -298,7 +298,7 @@ and ddb_regedits inspect drv_name drv_pciid =
* been copied.
*)
and copy_drivers g inspect driverdir =
- [] <> copy_from_libosinfo g inspect driverdir ||
+ (is_directory virtio_win && [] <> copy_from_libosinfo g inspect driverdir) ||
[] <> copy_from_virtio_win g inspect "/" driverdir
virtio_iso_path_matches_guest_os
(fun () ->
--
2.28.0
4 years
virt-v2v: Virtio-Scsi patch
by Jean-Louis Dupond
Hi,
I was trying to migrate some VM's to Virtio-SCSI block devices, as this
gives some advantages.
While checking the virt-v2v code, I found out that it supported
Virtio-SCSI, but some bits were missing.
In attachment a small patch that adds the missing bits :)
Best regards
Jean-Louis
4 years
Re: [Libguestfs] About libguestfs python3.6 command execution
by Richard W.M. Jones
On Sat, Nov 28, 2020 at 02:56:12AM +0300, İzzettin Erdem wrote:
> Hello Richard,
>
> I am working on OpenStack Sahara for a year and Sahara uses libguestfs for
> creating images according to the given .yaml file (sahara-image-pack bianry). I
> used this binary -and it worked- 6 months ago and after some version upgrades
> I've needed it again. When I try to create images I am taking errors from
> libguestfs.
>
> I did some research and in I found "sh" function in the guestfs.py file.
> Sahara-image-pack is using this function and sends it some commands but this
> function throws errors below. I tried to solve and did some tries to execute sh
> function with guestfs object but still the same.
>
> Main error is "guestfsd: error: /bin/sh: Exec format error". There is detailed
> logs below.
>
> I am kind of newbie, can you help me, please?
>
> http://paste.openstack.org/show/800516/
> http://paste.openstack.org/show/800517/
What version of libguestfs? Where did you get it from?
What is the output of "libguestfs-test-tool"?
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines. Boot with a
live CD or over the network (PXE) and turn machines into KVM guests.
http://libguestfs.org/virt-v2v
4 years
Re: [Libguestfs] virt-p2v NVMe disks
by Richard W.M. Jones
On Tue, Nov 10, 2020 at 11:53:19PM +0000, Femi Adegoke wrote:
> Actually I suspect we need to modify virt-p2v to recognize
> /dev/nvme* as a block device name.
>
> Hi Mr. Jones,
>
> Any approximate time frame on when the NVMe "mod" might happen?
I guess when someone contributes a patch.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines. Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top
4 years, 1 month
Re: [Libguestfs] virt-sparsify failed (was: [oVirt Jenkins] ovirt-system-tests_basic-suite-master_nightly - Build # 479 - Failure!)
by Nir Soffer
On Mon, Oct 12, 2020 at 9:05 AM Yedidyah Bar David <didi(a)redhat.com> wrote:
>
> Hi all,
>
> On Mon, Oct 12, 2020 at 5:17 AM <jenkins(a)jenkins.phx.ovirt.org> wrote:
> >
> > Project: https://jenkins.ovirt.org/job/ovirt-system-tests_basic-suite-master_nightly/
> > Build: https://jenkins.ovirt.org/job/ovirt-system-tests_basic-suite-master_night...
>
> Above failed with:
>
> https://jenkins.ovirt.org/job/ovirt-system-tests_basic-suite-master_night...
>
> vdsm.log has:
>
> https://jenkins.ovirt.org/job/ovirt-system-tests_basic-suite-master_night...
>
> 2020-10-11 22:05:14,695-0400 INFO (jsonrpc/1) [api.host] FINISH
> getJobs return={'jobs': {'05eaea44-7e4c-4442-9926-2bcb696520f1':
> {'id': '05eaea44-7e4c-4442-9926-2bcb696520f1', 'status': 'failed',
> 'description': 'sparsify_volume', 'job_type': 'storage', 'error':
> {'code': 100, 'message': 'General Exception: (\'Command
> [\\\'/usr/bin/virt-sparsify\\\', \\\'--machine-readable\\\',
> \\\'--in-place\\\',
> \\\'/rhev/data-center/mnt/192.168.200.4:_exports_nfs_share1/8b292c13-fd8a-4a7c-903c-5724ec742c10/images/a367c179-2ac9-4930-abeb-848229f81c97/515fcf06-8743-45d1-9af8-61a0c48e8c67\\\']
> failed with rc=1 out=b\\\'3/12\\\\n{ "message": "libguestfs error:
> guestfs_launch failed.\\\\\\\\nThis usually means the libguestfs
> appliance failed to start or crashed.\\\\\\\\nDo:\\\\\\\\n export
> LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1\\\\\\\\nand run the command
> again. For further information, read:\\\\\\\\n
> http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs\\\\\\\\nYou
> can also run \\\\\\\'libguestfs-test-tool\\\\\\\' and post the
> *complete* output\\\\\\\\ninto a bug report or message to the
> libguestfs mailing list.", "timestamp":
> "2020-10-11T22:05:08.397538670-04:00", "type": "error" }\\\\n\\\'
> err=b"virt-sparsify: error: libguestfs error: guestfs_launch
> failed.\\\\nThis usually means the libguestfs appliance failed to
> start or crashed.\\\\nDo:\\\\n export LIBGUESTFS_DEBUG=1
> LIBGUESTFS_TRACE=1\\\\nand run the command again. For further
> information, read:\\\\n
> http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs\\\\nYou
> can also run \\\'libguestfs-test-tool\\\' and post the *complete*
> output\\\\ninto a bug report or message to the libguestfs mailing
> list.\\\\n\\\\nIf reporting bugs, run virt-sparsify with debugging
> enabled and include the \\\\ncomplete output:\\\\n\\\\n virt-sparsify
> -v -x [...]\\\\n"\',)'}}}, 'status': {'code': 0, 'message': 'Done'}}
> from=::ffff:192.168.201.4,43318,
> flow_id=365642f4-2fe2-45df-937a-f4ca435eea38 (api:54)
> 2020-10-11 22:05:14,695-0400 DEBUG (jsonrpc/1) [jsonrpc.JsonRpcServer]
> Return 'Host.getJobs' in bridge with
> {'05eaea44-7e4c-4442-9926-2bcb696520f1': {'id':
> '05eaea44-7e4c-4442-9926-2bcb696520f1', 'status': 'failed',
> 'description': 'sparsify_volume', 'job_type': 'storage', 'error':
> {'code': 100, 'message': 'General Exception: (\'Command
> [\\\'/usr/bin/virt-sparsify\\\', \\\'--machine-readable\\\',
> \\\'--in-place\\\',
> \\\'/rhev/data-center/mnt/192.168.200.4:_exports_nfs_share1/8b292c13-fd8a-4a7c-903c-5724ec742c10/images/a367c179-2ac9-4930-abeb-848229f81c97/515fcf06-8743-45d1-9af8-61a0c48e8c67\\\']
> failed with rc=1 out=b\\\'3/12\\\\n{ "message": "libguestfs error:
> guestfs_launch failed.\\\\\\\\nThis usually means the libguestfs
> appliance failed to start or crashed.\\\\\\\\nDo:\\\\\\\\n export
> LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1\\\\\\\\nand run the command
> again. For further information, read:\\\\\\\\n
> http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs\\\\\\\\nYou
> can also run \\\\\\\'libguestfs-test-tool\\\\\\\' and post the
> *complete* output\\\\\\\\ninto a bug report or message to the
> libguestfs mailing list.", "timestamp":
> "2020-10-11T22:05:08.397538670-04:00", "type": "error" }\\\\n\\\'
> err=b"virt-sparsify: error: libguestfs error: guestfs_launch
> failed.\\\\nThis usually means the libguestfs appliance failed to
> start or crashed.\\\\nDo:\\\\n export LIBGUESTFS_DEBUG=1
> LIBGUESTFS_TRACE=1\\\\nand run the command again. For further
> information, read:\\\\n
> http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs\\\\nYou
> can also run \\\'libguestfs-test-tool\\\' and post the *complete*
> output\\\\ninto a bug report or message to the libguestfs mailing
> list.\\\\n\\\\nIf reporting bugs, run virt-sparsify with debugging
> enabled and include the \\\\ncomplete output:\\\\n\\\\n virt-sparsify
> -v -x [...]\\\\n"\',)'}}} (__init__:356)
>
> /var/log/messages has:
>
> Oct 11 22:04:51 lago-basic-suite-master-host-0 kvm[80601]: 1 guest now active
> Oct 11 22:05:06 lago-basic-suite-master-host-0 journal[80557]: Domain
> id=1 name='guestfs-hl0ntvn92rtkk2u0'
> uuid=05ea5a53-562f-49f8-a8ca-76b45c5325b4 is tainted: custom-argv
> Oct 11 22:05:06 lago-basic-suite-master-host-0 journal[80557]: Domain
> id=1 name='guestfs-hl0ntvn92rtkk2u0'
> uuid=05ea5a53-562f-49f8-a8ca-76b45c5325b4 is tainted: host-cpu
> Oct 11 22:05:06 lago-basic-suite-master-host-0 kvm[80801]: 2 guests now active
> Oct 11 22:05:08 lago-basic-suite-master-host-0 journal[80557]:
> internal error: End of file from qemu monitor
> Oct 11 22:05:08 lago-basic-suite-master-host-0 kvm[80807]: 1 guest now active
> Oct 11 22:05:08 lago-basic-suite-master-host-0 journal[80557]: cannot
> resolve symlink /tmp/libguestfseTG8xF/console.sock: No such file or
> directoryKN<F3>L^?
> Oct 11 22:05:08 lago-basic-suite-master-host-0 journal[80557]: cannot
> resolve symlink /tmp/libguestfseTG8xF/guestfsd.sock: No such file or
> directoryKN<F3>L^?
> Oct 11 22:05:08 lago-basic-suite-master-host-0 journal[80557]: cannot
> lookup default selinux label for /tmp/libguestfs1WkcF7/overlay1.qcow2
> Oct 11 22:05:08 lago-basic-suite-master-host-0 journal[80557]: cannot
> lookup default selinux label for
> /var/tmp/.guestfs-36/appliance.d/kernel
> Oct 11 22:05:08 lago-basic-suite-master-host-0 journal[80557]: cannot
> lookup default selinux label for
> /var/tmp/.guestfs-36/appliance.d/initrd
> Oct 11 22:05:08 lago-basic-suite-master-host-0 vdsm[74096]: ERROR Job
> '05eaea44-7e4c-4442-9926-2bcb696520f1' failed#012Traceback (most
> recent call last):#012 File
> "/usr/lib/python3.6/site-packages/vdsm/jobs.py", line 159, in run#012
> self._run()#012 File
> "/usr/lib/python3.6/site-packages/vdsm/storage/sdm/api/sparsify_volume.py",
> line 57, in _run#012
> virtsparsify.sparsify_inplace(self._vol_info.path)#012 File
> "/usr/lib/python3.6/site-packages/vdsm/virtsparsify.py", line 40, in
> sparsify_inplace#012 commands.run(cmd)#012 File
> "/usr/lib/python3.6/site-packages/vdsm/common/commands.py", line 101,
> in run#012 raise cmdutils.Error(args, p.returncode, out,
> err)#012vdsm.common.cmdutils.Error: Command ['/usr/bin/virt-sparsify',
> '--machine-readable', '--in-place',
> '/rhev/data-center/mnt/192.168.200.4:_exports_nfs_share1/8b292c13-fd8a-4a7c-903c-5724ec742c10/images/a367c179-2ac9-4930-abeb-848229f81c97/515fcf06-8743-45d1-9af8-61a0c48e8c67']
> failed with rc=1 out=b'3/12\n{ "message": "libguestfs error:
> guestfs_launch failed.\\nThis usually means the libguestfs appliance
> failed to start or crashed.\\nDo:\\n export LIBGUESTFS_DEBUG=1
> LIBGUESTFS_TRACE=1\\nand run the command again. For further
> information, read:\\n
> http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs\\nYou
> can also run \'libguestfs-test-tool\' and post the *complete*
> output\\ninto a bug report or message to the libguestfs mailing
> list.", "timestamp": "2020-10-11T22:05:08.397538670-04:00", "type":
> "error" }\n' err=b"virt-sparsify: error: libguestfs error:
> guestfs_launch failed.\nThis usually means the libguestfs appliance
> failed to start or crashed.\nDo:\n export LIBGUESTFS_DEBUG=1
> LIBGUESTFS_TRACE=1\nand run the command again. For further
> information, read:\n
> http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs\nYou can
> also run 'libguestfs-test-tool' and post the *complete* output\ninto a
> bug report or message to the libguestfs mailing list.\n\nIf reporting
> bugs, run virt-sparsify with debugging enabled and include the
> \ncomplete output:\n\n virt-sparsify -v -x [...]\n"
>
> The next run of the job (480) did finish successfully. No idea if it
> was already fixed by a patch, or is simply a random/env issue.
I think this is env issue, we run on overloaded vms with small amount of memory.
I have seen such radnom failures before.
> Is it possible to pass LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1 without
> patching vdsm? Not sure. In any case, if this does not cause too much
> excess debug logging, perhaps better always pass it, to help
> retroactively analyze such failures.
Unfortunately using LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1 creates
huge amount of logs so it is not possible to include these log for every run.
Maybe we can show the logs only if the command failed, but vdsm infrastructure
make this hard to do since we always log commnad stderr, even if the command
was successful.
Also I'm not sure this is a good idea to always run virt-sparsify in
debug level.
I think I posted a patch to run libguestfs-test-tool after virt-something errors
for collecting data, but I cannot find it. Maybe this can be useful,
so after every
virt-something error we will have enough info about the issue in vdsm log.
> Or, patch
> virt-sparsify/libguestfs/whatever to always log at least enough
> information on failure even without passing these.
I think this is the right solution - when virt-something tool fails,
it should log the
reason for the failure - the error that caused the tool to fail. I'm
not sure this is
easy to do as the failing code run inside a special VM. Maybe the code running
in the VM should log the output in a machine readable way, so once an error
is detected virt-something can report the error as the reason, without running
in debug mode.
Nir
4 years, 1 month
[PATCH libnbd] copy: Allowing copying from NBD server to NBD server.
by Richard W.M. Jones
This patch is a straightforward refactoring of libnbd’s nbdcopy
program, and not very interesting.
However I have plans for nbdcopy (see full todo below). I would like
to use this utility for virt-v2v as a replacement for ”qemu-img convert”.
qemu-img has caused us a series of problems:
- change in zeroing behaviour caused a big performance regression
- qemu-img reads extents up-front which is problematic when reading
from VDDK because the progress counter sticks at 0% for ages
- no support for NBD multi-conn, leaving a lot of performance on the table
- inflexible progress bar
The idea is to make nbdcopy into a very customizable and highly
efficient copying tool [it obviously is not right now].
Rich.
----------------------------------------------------------------------
progress bar
- write to fd
- machine-readable
threads
- how many copying threads do we create
read order, write order
- allow reads/writes in order or out of order
multi-conn
- control it separately at either end
extents
- do we check them at all?
- do we check them before or as we go along?
(probably best to always check as we go along?)
- do we zero up front or as we go along?
(best always as we go along?)
synchronous
- some kind of deliberately linear mode, eg for pipes
- with FUA on writes
--from / --to
- send data from/to an NBD server as subprocess
- can we do this?
block size
- force requests to be aligned to block size
support for copying ranges
- offset and size
- in a later version, since this is hard to get right
io_uring(?)
- in nbdcopy
- in libnbd
- later version - hard, needs benchmarking to prove it is worthwhile
4 years, 1 month
