From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37405) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VOIoN-00048w-Gh for qemu-devel@nongnu.org; Mon, 23 Sep 2013 22:57:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VOIoE-0005wQ-Fd for qemu-devel@nongnu.org; Mon, 23 Sep 2013 22:57:15 -0400 Received: from e28smtp04.in.ibm.com ([122.248.162.4]:36011) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VOIoD-0005wM-PX for qemu-devel@nongnu.org; Mon, 23 Sep 2013 22:57:06 -0400 Received: from /spool/local by e28smtp04.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 24 Sep 2013 08:26:57 +0530 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id B837CE0053 for ; Tue, 24 Sep 2013 08:27:57 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r8O2unS731326444 for ; Tue, 24 Sep 2013 08:26:52 +0530 Received: from d28av04.in.ibm.com (localhost [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id r8O2upqF010862 for ; Tue, 24 Sep 2013 08:26:51 +0530 Message-ID: <5240FF65.2090909@linux.vnet.ibm.com> Date: Tue, 24 Sep 2013 10:56:37 +0800 From: Wenchao Xia MIME-Version: 1.0 References: <1379842791-3776-1-git-send-email-xiawenc@linux.vnet.ibm.com> <1379842791-3776-3-git-send-email-xiawenc@linux.vnet.ibm.com> <52401735.7090503@redhat.com> In-Reply-To: <52401735.7090503@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH V2 2/4] qemu-nbd: support internal snapshot export List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: kwolf@redhat.com, stefanha@gmail.com, qemu-devel@nongnu.org 于 2013/9/23 18:25, Paolo Bonzini 写道: > Il 22/09/2013 11:39, Wenchao Xia ha scritto: >> Now it is possible to directly export an internal snapshot, which >> can be used to probe the snapshot's contents without qemu-img >> convert. >> >> Signed-off-by: Wenchao Xia >> --- >> qemu-nbd.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++++- >> 1 files changed, 53 insertions(+), 1 deletions(-) >> >> diff --git a/qemu-nbd.c b/qemu-nbd.c >> index c26c98e..e450d04 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 >> #include >> @@ -304,6 +305,23 @@ static void nbd_accept(void *opaque) >> } >> } >> >> +#define SNAPSHOT_OPT_ID "id" >> +#define SNAPSHOT_OPT_NAME "name" >> + >> +static QEMUOptionParameter snapshot_options[] = { >> + { >> + .name = SNAPSHOT_OPT_ID, >> + .type = OPT_STRING, >> + .help = "snapshot id" >> + }, >> + { >> + .name = SNAPSHOT_OPT_NAME, >> + .type = OPT_STRING, >> + .help = "snapshot name" >> + }, >> + { NULL } >> +}; > I think whatever mechanism you use here to pick a snapshot id or name > should be implemented in qemu-img too. qemu-img already pick up snapshot by mixed id and name, do you like to add a new interface like the above(Keep old interface untouched for compatiablity)? > Also, I think QEMUOptionParameter is being phased out. > Is QemuOptsList the recommanded method? >> int main(int argc, char **argv) >> { >> BlockDriverState *bs; >> @@ -315,7 +333,10 @@ 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"; >> + QEMUOptionParameter *sn_param = NULL; >> + const QEMUOptionParameter *sn_param_id, *sn_param_name; >> + const char *sn_id = NULL, *sn_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 +349,7 @@ int main(int argc, char **argv) >> { "connect", 1, NULL, 'c' }, >> { "disconnect", 0, NULL, 'd' }, >> { "snapshot", 0, NULL, 's' }, >> + { "snapshot-load", 1, NULL, 'l' }, > Please call this option "load-snapshot". > OK. > Paolo > >> { "nocache", 0, NULL, 'n' }, >> { "cache", 1, NULL, QEMU_NBD_OPT_CACHE }, >> #ifdef CONFIG_LINUX_AIO >> @@ -428,6 +450,14 @@ int main(int argc, char **argv) >> errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg); >> } >> break; >> + case 'l': >> + sn_param = parse_option_parameters(optarg, >> + snapshot_options, sn_param); >> + if (!sn_param) { >> + errx(EXIT_FAILURE, >> + "Invalid snapshot-load options '%s'", optarg); >> + } >> + /* fall through */ >> case 'r': >> nbdflags |= NBD_FLAG_READ_ONLY; >> flags&= ~BDRV_O_RDWR; >> @@ -581,6 +611,24 @@ int main(int argc, char **argv) >> error_get_pretty(local_err)); >> } >> >> + if (sn_param) { >> + sn_param_id = get_option_parameter(sn_param, SNAPSHOT_OPT_ID); >> + sn_param_name = get_option_parameter(sn_param, SNAPSHOT_OPT_NAME); >> + if (sn_param_id) { >> + sn_id = sn_param_id->value.s; >> + } >> + if (sn_param_name) { >> + sn_name = sn_param_name->value.s; >> + } >> + ret = bdrv_snapshot_load_tmp(bs, sn_id, sn_name,&local_err); >> + if (ret< 0) { >> + errno = -ret; >> + err(EXIT_FAILURE, >> + "Failed to load snapshot, reason:\n%s", >> + error_get_pretty(local_err)); >> + } >> + } >> + >> fd_size = bdrv_getlength(bs); >> >> if (partition != -1) { >> @@ -641,6 +689,10 @@ int main(int argc, char **argv) >> unlink(sockpath); >> } >> >> + if (sn_param) { >> + free_option_parameters(sn_param); >> + } >> + >> if (device) { >> void *ret; >> pthread_join(client_thread,&ret); >>