qemu-nbd: add option to set detect-zeroes mode

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Peter Lieven 2014-08-13 19:20:18 +02:00 committed by Stefan Hajnoczi
parent 9e7dac7c6c
commit b3838a4088

View file

@ -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>
@ -41,6 +43,7 @@
#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;
@ -96,6 +99,8 @@ static void usage(const char *name)
#ifdef CONFIG_LINUX_AIO
" --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) {