From 636192c4b6052820ea126a5287c58a8f53f3c84f Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 11 Jan 2019 13:47:20 -0600 Subject: [PATCH] qemu-nbd: Add --bitmap=NAME option Having to fire up qemu, then use QMP commands for nbd-server-start and nbd-server-add, just to expose a persistent dirty bitmap, is rather tedious. Make it possible to expose a dirty bitmap using just qemu-nbd (of course, for now this only works when qemu-nbd is visiting a BDS formatted as qcow2). Of course, any good feature also needs unit testing, so expand iotest 223 to cover it. Signed-off-by: Eric Blake Message-Id: <20190111194720.15671-9-eblake@redhat.com> --- qemu-nbd.c | 10 ++++++++-- qemu-nbd.texi | 4 ++++ tests/qemu-iotests/223 | 18 +++++++++++++++++- tests/qemu-iotests/223.out | 12 +++++++++++- 4 files changed, 40 insertions(+), 4 deletions(-) diff --git a/qemu-nbd.c b/qemu-nbd.c index 1552274c189..51b55f2e066 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -95,6 +95,7 @@ static void usage(const char *name) "Exposing part of the image:\n" " -o, --offset=OFFSET offset into the image\n" " -P, --partition=NUM only expose partition NUM\n" +" -B, --bitmap=NAME expose a persistent dirty bitmap\n" "\n" "General purpose options:\n" " --object type,id=ID,... define an object such as 'secret' for providing\n" @@ -509,7 +510,7 @@ int main(int argc, char **argv) off_t fd_size; QemuOpts *sn_opts = NULL; const char *sn_id_or_name = NULL; - const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:"; + const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:"; struct option lopt[] = { { "help", no_argument, NULL, 'h' }, { "version", no_argument, NULL, 'V' }, @@ -519,6 +520,7 @@ int main(int argc, char **argv) { "offset", required_argument, NULL, 'o' }, { "read-only", no_argument, NULL, 'r' }, { "partition", required_argument, NULL, 'P' }, + { "bitmap", required_argument, NULL, 'B' }, { "connect", required_argument, NULL, 'c' }, { "disconnect", no_argument, NULL, 'd' }, { "snapshot", no_argument, NULL, 's' }, @@ -558,6 +560,7 @@ int main(int argc, char **argv) QDict *options = NULL; const char *export_name = ""; /* Default export name */ const char *export_description = NULL; + const char *bitmap = NULL; const char *tlscredsid = NULL; bool imageOpts = false; bool writethrough = true; @@ -695,6 +698,9 @@ int main(int argc, char **argv) exit(EXIT_FAILURE); } break; + case 'B': + bitmap = optarg; + break; case 'k': sockpath = optarg; if (sockpath[0] != '/') { @@ -1016,7 +1022,7 @@ int main(int argc, char **argv) } export = nbd_export_new(bs, dev_offset, fd_size, export_name, - export_description, NULL, nbdflags, + export_description, bitmap, nbdflags, nbd_export_closed, writethrough, NULL, &error_fatal); diff --git a/qemu-nbd.texi b/qemu-nbd.texi index 9a84e81eed9..96b1546006a 100644 --- a/qemu-nbd.texi +++ b/qemu-nbd.texi @@ -45,6 +45,10 @@ auto-detecting Export the disk as read-only @item -P, --partition=@var{num} Only expose partition @var{num} +@item -B, --bitmap=@var{name} +If @var{filename} has a qcow2 persistent bitmap @var{name}, expose +that bitmap via the ``qemu:dirty-bitmap:@var{name}'' context +accessible through NBD_OPT_SET_META_CONTEXT. @item -s, --snapshot Use @var{filename} as an external snapshot, create a temporary file with backing_file=@var{filename}, redirect the write to diff --git a/tests/qemu-iotests/223 b/tests/qemu-iotests/223 index 0bcc98a8677..773892dbe60 100755 --- a/tests/qemu-iotests/223 +++ b/tests/qemu-iotests/223 @@ -25,6 +25,7 @@ status=1 # failure is the default! _cleanup() { + nbd_server_stop _cleanup_test_img _cleanup_qemu rm -f "$TEST_DIR/nbd" @@ -35,6 +36,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15 . ./common.rc . ./common.filter . ./common.qemu +. ./common.nbd _supported_fmt qcow2 _supported_proto file # uses NBD as well @@ -163,7 +165,7 @@ $QEMU_IMG map --output=json --image-opts \ "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b2" | _filter_qemu_img_map echo -echo "=== End NBD server ===" +echo "=== End qemu NBD server ===" echo _send_qemu_cmd $QEMU_HANDLE '{"execute":"nbd-server-remove", @@ -176,6 +178,20 @@ _send_qemu_cmd $QEMU_HANDLE '{"execute":"nbd-server-stop"}' "return" _send_qemu_cmd $QEMU_HANDLE '{"execute":"nbd-server-stop"}' "error" # Again _send_qemu_cmd $QEMU_HANDLE '{"execute":"quit"}' "return" +echo +echo "=== Use qemu-nbd as server ===" +echo + +nbd_server_start_unix_socket -r -f $IMGFMT -B b "$TEST_IMG" +IMG="driver=nbd,server.type=unix,server.path=$nbd_unix_socket" +$QEMU_IMG map --output=json --image-opts \ + "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b" | _filter_qemu_img_map + +nbd_server_start_unix_socket -f $IMGFMT -B b2 "$TEST_IMG" +IMG="driver=nbd,server.type=unix,server.path=$nbd_unix_socket" +$QEMU_IMG map --output=json --image-opts \ + "$IMG,x-dirty-bitmap=qemu:dirty-bitmap:b2" | _filter_qemu_img_map + # success, all done echo '*** done' rm -f $seq.full diff --git a/tests/qemu-iotests/223.out b/tests/qemu-iotests/223.out index ebd3935c974..0de5240a75e 100644 --- a/tests/qemu-iotests/223.out +++ b/tests/qemu-iotests/223.out @@ -61,7 +61,7 @@ read 2097152/2097152 bytes at offset 2097152 { "start": 1024, "length": 2096128, "depth": 0, "zero": false, "data": true}, { "start": 2097152, "length": 2097152, "depth": 0, "zero": false, "data": false}] -=== End NBD server === +=== End qemu NBD server === {"return": {}} {"return": {}} @@ -69,4 +69,14 @@ read 2097152/2097152 bytes at offset 2097152 {"return": {}} {"error": {"class": "GenericError", "desc": "NBD server not running"}} {"return": {}} + +=== Use qemu-nbd as server === + +[{ "start": 0, "length": 65536, "depth": 0, "zero": false, "data": false}, +{ "start": 65536, "length": 2031616, "depth": 0, "zero": false, "data": true}, +{ "start": 2097152, "length": 2097152, "depth": 0, "zero": false, "data": false}] +[{ "start": 0, "length": 512, "depth": 0, "zero": false, "data": true}, +{ "start": 512, "length": 512, "depth": 0, "zero": false, "data": false}, +{ "start": 1024, "length": 2096128, "depth": 0, "zero": false, "data": true}, +{ "start": 2097152, "length": 2097152, "depth": 0, "zero": false, "data": false}] *** done -- 2.39.2