From 0406c2a938cf46c81c2d6c8ed14a4994993a3860 Mon Sep 17 00:00:00 2001

From: John Snow <jsnow@redhat.com>

Date: Wed, 27 Mar 2019 17:22:45 +0100

Subject: [PATCH 107/163] nbd/client: Split out nbd_send_meta_query()

RH-Author: John Snow <jsnow@redhat.com>

Message-id: <20190327172308.31077-33-jsnow@redhat.com>

Patchwork-id: 85202

O-Subject: [RHEL-7.7 qemu-kvm-rhev PATCH 32/55] nbd/client: Split out nbd_send_meta_query()

Bugzilla: 1691009

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

RH-Acked-by: Max Reitz <mreitz@redhat.com>

RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

From: Eric Blake <eblake@redhat.com>

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 <eblake@redhat.com>

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>

Message-Id: <20190117193658.16413-12-eblake@redhat.com>

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

(cherry picked from commit 757b3ab989dea1c3143dd0d499441415ac7fcbc0)

Signed-off-by: John Snow <jsnow@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 nbd/client.c     | 64 ++++++++++++++++++++++++++++++++++++++------------------

 nbd/trace-events |  2 +-

 2 files changed, 45 insertions(+), 21 deletions(-)

diff --git a/nbd/client.c b/nbd/client.c

index 7799389..96da68e 100644

--- a/nbd/client.c

+++ b/nbd/client.c

@@ -629,6 +629,46 @@ static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,

     return QIO_CHANNEL(tioc);

 }

+/*

+ * nbd_send_meta_query:

+ * Send 0 or 1 set/list meta context queries.

+ * Return 0 on success, -1 with errp set for any error

+ */

+static int nbd_send_meta_query(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;

+    uint32_t query_len = 0;

+    uint32_t data_len;

+    char *data;

+    char *p;

+

+    data_len = sizeof(export_len) + export_len + sizeof(queries);

+    if (query) {

+        query_len = strlen(query);

+        data_len += sizeof(query_len) + query_len;

+    } else {

+        assert(opt == NBD_OPT_LIST_META_CONTEXT);

+    }

+    p = data = g_malloc(data_len);

+

+    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(queries), query_len);

+        memcpy(p += sizeof(query_len), query, query_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 +693,10 @@ 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_meta_query(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 +713,7 @@ 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 c3966d2..59521e4 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"

 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

-- 

1.8.3.1