diff options
| -rw-r--r-- | block/snapshot.c | 18 | ||||
| -rw-r--r-- | include/block/snapshot.h | 8 | ||||
| -rw-r--r-- | qemu-nbd.c | 46 | ||||
| -rw-r--r-- | qemu-nbd.texi | 8 |
4 files changed, 77 insertions, 3 deletions
diff --git a/block/snapshot.c b/block/snapshot.c index 565222e24a..9047f8ddc9 100644 --- a/block/snapshot.c +++ b/block/snapshot.c @@ -25,6 +25,24 @@ #include "block/snapshot.h" #include "block/block_int.h" +QemuOptsList internal_snapshot_opts = { + .name = "snapshot", + .head = QTAILQ_HEAD_INITIALIZER(internal_snapshot_opts.head), + .desc = { + { + .name = SNAPSHOT_OPT_ID, + .type = QEMU_OPT_STRING, + .help = "snapshot id" + },{ + .name = SNAPSHOT_OPT_NAME, + .type = QEMU_OPT_STRING, + .help = "snapshot name" + },{ + /* end of list */ + } + }, +}; + int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info, const char *name) { diff --git a/include/block/snapshot.h b/include/block/snapshot.h index d05bea7223..770d9bbc8c 100644 --- a/include/block/snapshot.h +++ b/include/block/snapshot.h @@ -27,6 +27,14 @@ #include "qemu-common.h" #include "qapi/error.h" +#include "qemu/option.h" + + +#define SNAPSHOT_OPT_BASE "snapshot." +#define SNAPSHOT_OPT_ID "snapshot.id" +#define SNAPSHOT_OPT_NAME "snapshot.name" + +extern QemuOptsList internal_snapshot_opts; typedef struct QEMUSnapshotInfo { char id_str[128]; /* unique snapshot id */ diff --git a/qemu-nbd.c b/qemu-nbd.c index c26c98ef1d..fe6053ca56 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -20,6 +20,7 @@ #include "block/block.h" #include "block/nbd.h" #include "qemu/main-loop.h" +#include "block/snapshot.h" #include <stdarg.h> #include <stdio.h> @@ -79,7 +80,14 @@ static void usage(const char *name) "\n" "Block device options:\n" " -r, --read-only export read-only\n" -" -s, --snapshot use snapshot file\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" #ifdef CONFIG_LINUX_AIO @@ -315,7 +323,9 @@ int main(int argc, char **argv) char *device = NULL; int port = NBD_DEFAULT_PORT; off_t fd_size; - const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:t"; + QemuOpts *sn_opts = NULL; + const char *sn_id_or_name = NULL; + const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:"; struct option lopt[] = { { "help", 0, NULL, 'h' }, { "version", 0, NULL, 'V' }, @@ -328,6 +338,7 @@ int main(int argc, char **argv) { "connect", 1, NULL, 'c' }, { "disconnect", 0, NULL, 'd' }, { "snapshot", 0, NULL, 's' }, + { "load-snapshot", 1, NULL, 'l' }, { "nocache", 0, NULL, 'n' }, { "cache", 1, NULL, QEMU_NBD_OPT_CACHE }, #ifdef CONFIG_LINUX_AIO @@ -428,6 +439,17 @@ int main(int argc, char **argv) errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg); } break; + case 'l': + if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { + sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0); + if (!sn_opts) { + errx(EXIT_FAILURE, "Failed in parsing snapshot param `%s'", + optarg); + } + } else { + sn_id_or_name = optarg; + } + /* fall through */ case 'r': nbdflags |= NBD_FLAG_READ_ONLY; flags &= ~BDRV_O_RDWR; @@ -581,6 +603,22 @@ int main(int argc, char **argv) error_get_pretty(local_err)); } + if (sn_opts) { + ret = bdrv_snapshot_load_tmp(bs, + qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), + qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), + &local_err); + } else if (sn_id_or_name) { + ret = bdrv_snapshot_load_tmp_by_id_or_name(bs, sn_id_or_name, + &local_err); + } + if (ret < 0) { + errno = -ret; + err(EXIT_FAILURE, + "Failed to load snapshot: %s", + error_get_pretty(local_err)); + } + fd_size = bdrv_getlength(bs); if (partition != -1) { @@ -641,6 +679,10 @@ int main(int argc, char **argv) unlink(sockpath); } + if (sn_opts) { + qemu_opts_del(sn_opts); + } + if (device) { void *ret; pthread_join(client_thread, &ret); diff --git a/qemu-nbd.texi b/qemu-nbd.texi index 6055ec693b..5b55f769ac 100644 --- a/qemu-nbd.texi +++ b/qemu-nbd.texi @@ -27,7 +27,13 @@ Export QEMU disk image using NBD protocol. @item -P, --partition=@var{num} only expose partition @var{num} @item -s, --snapshot - use snapshot file + use @var{filename} as an external snapshot, create a temporary + file with backing_file=@var{filename}, redirect the write to + the temporary one +@item -l, --load-snapshot=@var{snapshot_param} + load an internal snapshot inside @var{filename} and export it + as an read-only device, @var{snapshot_param} format is + 'snapshot.id=[ID],snapshot.name=[NAME]' or '[ID_OR_NAME]' @item -n, --nocache @itemx --cache=@var{cache} set cache mode to be used with the file. See the documentation of |