@@ -18,11 +18,13 @@
#include "qemu-common.h"
#include "block/block.h"
+#include "block/block_int.h"
#include "block/nbd.h"
#include "qemu/main-loop.h"
#include "qemu/sockets.h"
#include "qemu/error-report.h"
#include "block/snapshot.h"
+#include "qapi/util.h"
#include <stdarg.h>
#include <stdio.h>
@@ -38,9 +40,10 @@
#include <pthread.h>
#define SOCKET_PATH "/var/lock/qemu-nbd-%s"
-#define QEMU_NBD_OPT_CACHE 1
-#define QEMU_NBD_OPT_AIO 2
-#define QEMU_NBD_OPT_DISCARD 3
+#define QEMU_NBD_OPT_CACHE 1
+#define QEMU_NBD_OPT_AIO 2
+#define QEMU_NBD_OPT_DISCARD 3
+#define QEMU_NBD_OPT_DETECT_ZEROES 4
static NBDExport *exp;
static int verbose;
@@ -57,45 +60,47 @@ static void usage(const char *name)
"Usage: %s [OPTIONS] FILE\n"
"QEMU Disk Network Block Device Server\n"
"\n"
-" -h, --help display this help and exit\n"
-" -V, --version output version information and exit\n"
+" -h, --help display this help and exit\n"
+" -V, --version output version information and exit\n"
"\n"
"Connection properties:\n"
-" -p, --port=PORT port to listen on (default `%d')\n"
-" -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
-" -k, --socket=PATH path to the unix socket\n"
-" (default '"SOCKET_PATH"')\n"
-" -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
-" -t, --persistent don't exit on the last connection\n"
-" -v, --verbose display extra debugging information\n"
+" -p, --port=PORT port to listen on (default `%d')\n"
+" -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n"
+" -k, --socket=PATH path to the unix socket\n"
+" (default '"SOCKET_PATH"')\n"
+" -e, --shared=NUM device can be shared by NUM clients (default '1')\n"
+" -t, --persistent don't exit on the last connection\n"
+" -v, --verbose display extra debugging information\n"
"\n"
"Exposing part of the image:\n"
-" -o, --offset=OFFSET offset into the image\n"
-" -P, --partition=NUM only expose partition NUM\n"
+" -o, --offset=OFFSET offset into the image\n"
+" -P, --partition=NUM only expose partition NUM\n"
"\n"
#ifdef __linux__
"Kernel NBD client support:\n"
-" -c, --connect=DEV connect FILE to the local NBD device DEV\n"
-" -d, --disconnect disconnect the specified device\n"
+" -c, --connect=DEV connect FILE to the local NBD device DEV\n"
+" -d, --disconnect disconnect the specified device\n"
"\n"
#endif
"\n"
"Block device options:\n"
-" -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
-" -r, --read-only export read-only\n"
-" -s, --snapshot use FILE as an external snapshot, create a temporary\n"
-" file with backing_file=FILE, redirect the write to\n"
-" the temporary one\n"
+" -f, --format=FORMAT set image format (raw, qcow2, ...)\n"
+" -r, --read-only export read-only\n"
+" -s, --snapshot use FILE as an external snapshot, create a temporary\n"
+" file with backing_file=FILE, redirect the write to\n"
+" the temporary one\n"
" -l, --load-snapshot=SNAPSHOT_PARAM\n"
-" load an internal snapshot inside FILE and export it\n"
-" as an read-only device, SNAPSHOT_PARAM format is\n"
-" 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
-" '[ID_OR_NAME]'\n"
-" -n, --nocache disable host cache\n"
-" --cache=MODE set cache mode (none, writeback, ...)\n"
+" load an internal snapshot inside FILE and export it\n"
+" as an read-only device, SNAPSHOT_PARAM format is\n"
+" 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
+" '[ID_OR_NAME]'\n"
+" -n, --nocache disable host cache\n"
+" --cache=MODE set cache mode (none, writeback, ...)\n"
#ifdef CONFIG_LINUX_AIO
-" --aio=MODE set AIO mode (native or threads)\n"
+" --aio=MODE set AIO mode (native or threads)\n"
#endif
+" --discard=MODE set discard mode (ignore, unmap)\n"
+" --detect-zeroes=MODE set detect-zeroes mode (off, on, discard)\n"
"\n"
"Report bugs to <qemu-devel@nongnu.org>\n"
, name, NBD_DEFAULT_PORT, "DEVICE");
@@ -410,6 +415,7 @@ int main(int argc, char **argv)
{ "aio", 1, NULL, QEMU_NBD_OPT_AIO },
#endif
{ "discard", 1, NULL, QEMU_NBD_OPT_DISCARD },
+ { "detect-zeroes", 1, NULL, QEMU_NBD_OPT_DETECT_ZEROES },
{ "shared", 1, NULL, 'e' },
{ "format", 1, NULL, 'f' },
{ "persistent", 0, NULL, 't' },
@@ -432,6 +438,7 @@ int main(int argc, char **argv)
pthread_t client_thread;
const char *fmt = NULL;
Error *local_err = NULL;
+ BlockdevDetectZeroesOptions detect_zeroes = BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
/* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
@@ -483,6 +490,23 @@ int main(int argc, char **argv)
errx(EXIT_FAILURE, "Invalid discard mode `%s'", optarg);
}
break;
+ case QEMU_NBD_OPT_DETECT_ZEROES:
+ detect_zeroes =
+ qapi_enum_parse(BlockdevDetectZeroesOptions_lookup,
+ optarg,
+ BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX,
+ BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
+ &local_err);
+ if (local_err) {
+ errx(EXIT_FAILURE, "Failed to parse detect_zeroes mode: %s",
+ error_get_pretty(local_err));
+ }
+ if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
+ !(flags & BDRV_O_UNMAP)) {
+ errx(EXIT_FAILURE, "setting detect-zeroes to unmap is not allowed "
+ "without setting discard operation to unmap");
+ }
+ break;
case 'b':
bindto = optarg;
break;
@@ -686,6 +710,7 @@ int main(int argc, char **argv)
error_get_pretty(local_err));
}
+ bs->detect_zeroes = detect_zeroes;
fd_size = bdrv_getlength(bs);
if (partition != -1) {
Signed-off-by: Peter Lieven <pl@kamp.de> --- qemu-nbd.c | 81 +++++++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 53 insertions(+), 28 deletions(-)