[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v3 10/19] nbd/client: Split out nbd_send_one_met
From: |
Vladimir Sementsov-Ogievskiy |
Subject: |
Re: [Qemu-devel] [PATCH v3 10/19] nbd/client: Split out nbd_send_one_meta_context() |
Date: |
Tue, 15 Jan 2019 13:18:48 +0000 |
12.01.2019 20:58, Eric Blake wrote:
> Refactor nbd_negotiate_simple_meta_context() to pull out the
> code that can be reused to send a LIST request for 0 or 1 query.
> No semantic change. The old comment about 'sizeof(uint32_t)'
> being equivalent to '/* number of queries */' is no longer
> needed, now that we are computing 'sizeof(queries)' instead.
>
> Signed-off-by: Eric Blake <address@hidden>
> Message-Id: <address@hidden>
> Reviewed-by: Richard W.M. Jones <address@hidden>
>
> ---
> v3: Improve commit message [Rich], formatting tweak [checkpatch],
> rebase to dropped patch
> ---
> nbd/client.c | 67 +++++++++++++++++++++++++++++++++---------------
> nbd/trace-events | 2 +-
> 2 files changed, 48 insertions(+), 21 deletions(-)
>
> diff --git a/nbd/client.c b/nbd/client.c
> index 77993890f04..3c716be2719 100644
> --- a/nbd/client.c
> +++ b/nbd/client.c
> @@ -629,6 +629,49 @@ static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
> return QIO_CHANNEL(tioc);
> }
>
> +/*
> + * nbd_send_one_meta_context:
> + * Send 0 or 1 set/list meta context queries.
> + * Return 0 on success, -1 with errp set for any error
> + */
> +static int nbd_send_one_meta_context(QIOChannel *ioc,
> + uint32_t opt,
> + const char *export,
> + const char *query,
> + Error **errp)
> +{
> + int ret;
> + uint32_t export_len = strlen(export);
> + uint32_t queries = !!query;
n_ or nb_ prefix may make it more clear
> + uint32_t context_len = 0;
> + uint32_t data_len;
> + char *data;
> + char *p;
> +
> + data_len = sizeof(export_len) + export_len + sizeof(queries);
> + if (query) {
> + context_len = strlen(query);
looks like it then should be query_len
> + data_len += sizeof(context_len) + context_len;
> + } else {
> + assert(opt == NBD_OPT_LIST_META_CONTEXT);
> + }
> + data = g_malloc(data_len);
> + p = data;
may use p = data = g_malloc
> +
> + trace_nbd_opt_meta_request(nbd_opt_lookup(opt), query ?: "(all)",
> export);
> + stl_be_p(p, export_len);
> + memcpy(p += sizeof(export_len), export, export_len);
> + stl_be_p(p += export_len, queries);
> + if (query) {
> + stl_be_p(p += sizeof(uint32_t), context_len);
:), aha, please, s/uint32_t/queries, as you promised
Hmm, its my code. It's hard to read and not very comfortable to maintain..
In block/nbd-client.c we have
payload_advance* functions, to read such formatted data, I think, it should be
good to make something like this for server-part. Not about these series, of
course.
Interesting, troubles around "don't use be64_to_cpuS, use only be64_to_cpu",
do they apply somehow to *_be_p functions family?
> + memcpy(p += sizeof(context_len), query, context_len);
> + }
> +
> + ret = nbd_send_option_request(ioc, opt, data_len, data, errp);
> + g_free(data);
> + return ret;
> +}
> +
> /* nbd_negotiate_simple_meta_context:
> * Request the server to set the meta context for export @info->name
> * using @info->x_dirty_bitmap with a fallback to "base:allocation",
> @@ -653,26 +696,10 @@ static int nbd_negotiate_simple_meta_context(QIOChannel
> *ioc,
> NBDOptionReply reply;
> const char *context = info->x_dirty_bitmap ?: "base:allocation";
> bool received = false;
> - uint32_t export_len = strlen(info->name);
> - uint32_t context_len = strlen(context);
> - uint32_t data_len = sizeof(export_len) + export_len +
> - sizeof(uint32_t) + /* number of queries */
> - sizeof(context_len) + context_len;
> - char *data = g_malloc(data_len);
> - char *p = data;
>
> - trace_nbd_opt_meta_request(context, info->name);
> - stl_be_p(p, export_len);
> - memcpy(p += sizeof(export_len), info->name, export_len);
> - stl_be_p(p += export_len, 1);
> - stl_be_p(p += sizeof(uint32_t), context_len);
> - memcpy(p += sizeof(context_len), context, context_len);
> -
> - ret = nbd_send_option_request(ioc, NBD_OPT_SET_META_CONTEXT, data_len,
> data,
> - errp);
> - g_free(data);
> - if (ret < 0) {
> - return ret;
> + if (nbd_send_one_meta_context(ioc, NBD_OPT_SET_META_CONTEXT,
> + info->name, context, errp) < 0) {
> + return -1;
> }
>
> if (nbd_receive_option_reply(ioc, NBD_OPT_SET_META_CONTEXT, &reply,
> @@ -689,7 +716,7 @@ static int nbd_negotiate_simple_meta_context(QIOChannel
> *ioc,
> if (reply.type == NBD_REP_META_CONTEXT) {
> char *name;
>
> - if (reply.length != sizeof(info->context_id) + context_len) {
> + if (reply.length != sizeof(info->context_id) + strlen(context)) {
> error_setg(errp, "Failed to negotiate meta context '%s', server
> "
> "answered with unexpected length %" PRIu32, context,
> reply.length);
> diff --git a/nbd/trace-events b/nbd/trace-events
> index c3966d2b653..59521e47a3d 100644
> --- a/nbd/trace-events
> +++ b/nbd/trace-events
> @@ -12,7 +12,7 @@ nbd_receive_query_exports_start(const char *wantname)
> "Querying export list for
> nbd_receive_query_exports_success(const char *wantname) "Found desired
> export name '%s'"
> nbd_receive_starttls_new_client(void) "Setting up TLS"
> nbd_receive_starttls_tls_handshake(void) "Starting TLS handshake"
> -nbd_opt_meta_request(const char *context, const char *export) "Requesting to
> set meta context %s for export %s"
> +nbd_opt_meta_request(const char *optname, const char *context, const char
> *export) "Requesting %s %s for export %s"
Hmm, you forget nbd_opt_lookup()
With this and s/uint32_t/queries (other tiny things up to you):
Reviewed-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> nbd_opt_meta_reply(const char *context, uint32_t id) "Received mapping of
> context %s to id %" PRIu32
> nbd_receive_negotiate(void *tlscreds, const char *hostname) "Receiving
> negotiation tlscreds=%p hostname=%s"
> nbd_receive_negotiate_magic(uint64_t magic) "Magic is 0x%" PRIx64
>
--
Best regards,
Vladimir
- [Qemu-devel] [PATCH v3 00/19] nbd: add qemu-nbd --list, Eric Blake, 2019/01/12
- [Qemu-devel] [PATCH v3 16/19] nbd/client: Add meta contexts to nbd_receive_export_list(), Eric Blake, 2019/01/12
- [Qemu-devel] [PATCH v3 17/19] qemu-nbd: Add --list option, Eric Blake, 2019/01/12
- [Qemu-devel] [PATCH v3 19/19] iotests: Enhance 223, 233 to cover 'qemu-nbd --list', Eric Blake, 2019/01/12
- [Qemu-devel] [PATCH v3 07/19] nbd/client: Refactor nbd_receive_list(), Eric Blake, 2019/01/12
- [Qemu-devel] [PATCH v3 10/19] nbd/client: Split out nbd_send_one_meta_context(), Eric Blake, 2019/01/12
- Re: [Qemu-devel] [PATCH v3 10/19] nbd/client: Split out nbd_send_one_meta_context(),
Vladimir Sementsov-Ogievskiy <=
- Re: [Qemu-devel] [PATCH v3 10/19] nbd/client: Split out nbd_send_one_meta_context(), Vladimir Sementsov-Ogievskiy, 2019/01/16
[Qemu-devel] [PATCH v3 13/19] nbd/client: Split handshake into two functions, Eric Blake, 2019/01/12
[Qemu-devel] [PATCH v3 09/19] nbd/client: Change signature of nbd_negotiate_simple_meta_context(), Eric Blake, 2019/01/12
[Qemu-devel] [PATCH v3 15/19] nbd/client: Add nbd_receive_export_list(), Eric Blake, 2019/01/12