Commit 138796d0 authored by Eric Blake's avatar Eric Blake
Browse files

nbd/client: Refactor nbd_opt_go() to support NBD_OPT_INFO 



Rename the function to nbd_opt_info_or_go() with an added parameter
and slight changes to comments and trace messages, in order to
reuse the function for NBD_OPT_INFO.

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-Id: <20190117193658.16413-17-eblake@redhat.com>
Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
parent b3c9d33b

nbd/client.c

+22 −14
Original line number Diff line number Diff line
@@ -330,11 +330,16 @@ static int nbd_receive_list(QIOChannel *ioc, char **name, char **description, 
}





/* Returns -1 if NBD_OPT_GO proves the export @info->name cannot be

 * used, 0 if NBD_OPT_GO is unsupported (fall back to NBD_OPT_LIST and

/*

 * nbd_opt_info_or_go:

 * Send option for NBD_OPT_INFO or NBD_OPT_GO and parse the reply.

 * Returns -1 if the option proves the export @info->name cannot be

 * used, 0 if the option is unsupported (fall back to NBD_OPT_LIST and

 * NBD_OPT_EXPORT_NAME in that case), and > 0 if the export is good to

 * go (with the rest of @info populated). */

static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp)

 * go (with the rest of @info populated).

 */

static int nbd_opt_info_or_go(QIOChannel *ioc, uint32_t opt,

                              NBDExportInfo *info, Error **errp)

{

    NBDOptionReply reply;

    uint32_t len = strlen(info->name);
@@ -347,7 +352,8 @@ static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp) 
     * flags still 0 is a witness of a broken server. */

    info->flags = 0;



    trace_nbd_opt_go_start(info->name);

    assert(opt == NBD_OPT_GO || opt == NBD_OPT_INFO);

    trace_nbd_opt_info_go_start(nbd_opt_lookup(opt), info->name);

    buf = g_malloc(4 + len + 2 + 2 * info->request_sizes + 1);

    stl_be_p(buf, len);

    memcpy(buf + 4, info->name, len);
@@ -356,7 +362,7 @@ static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp) 
    if (info->request_sizes) {

        stw_be_p(buf + 4 + len + 2, NBD_INFO_BLOCK_SIZE);

    }

    error = nbd_send_option_request(ioc, NBD_OPT_GO,

    error = nbd_send_option_request(ioc, opt,

                                    4 + len + 2 + 2 * info->request_sizes,

                                    buf, errp);

    g_free(buf);
@@ -365,7 +371,7 @@ static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp) 
    }



    while (1) {

        if (nbd_receive_option_reply(ioc, NBD_OPT_GO, &reply, errp) < 0) {

        if (nbd_receive_option_reply(ioc, opt, &reply, errp) < 0) {

            return -1;

        }

        error = nbd_handle_reply_err(ioc, &reply, errp);
@@ -375,8 +381,10 @@ static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp) 
        len = reply.length;



        if (reply.type == NBD_REP_ACK) {

            /* Server is done sending info and moved into transmission

               phase, but make sure it sent flags */

            /*

             * Server is done sending info, and moved into transmission

             * phase for NBD_OPT_GO, but make sure it sent flags

             */

            if (len) {

                error_setg(errp, "server sent invalid NBD_REP_ACK");

                return -1;
@@ -385,7 +393,7 @@ static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp) 
                error_setg(errp, "broken server omitted NBD_INFO_EXPORT");

                return -1;

            }

            trace_nbd_opt_go_success();

            trace_nbd_opt_info_go_success(nbd_opt_lookup(opt));

            return 1;

        }

        if (reply.type != NBD_REP_INFO) {
@@ -479,12 +487,12 @@ static int nbd_opt_go(QIOChannel *ioc, NBDExportInfo *info, Error **errp) 
                nbd_send_opt_abort(ioc);

                return -1;

            }

            trace_nbd_opt_go_info_block_size(info->min_block, info->opt_block,

            trace_nbd_opt_info_block_size(info->min_block, info->opt_block,

                                          info->max_block);

            break;



        default:

            trace_nbd_opt_go_info_unknown(type, nbd_info_lookup(type));

            trace_nbd_opt_info_unknown(type, nbd_info_lookup(type));

            if (nbd_drop(ioc, len, errp) < 0) {

                error_prepend(errp, "Failed to read info payload: ");

                nbd_send_opt_abort(ioc);
@@ -993,7 +1001,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds, 
         * TLS).  If it is not available, fall back to

         * NBD_OPT_LIST for nicer error messages about a missing

         * export, then use NBD_OPT_EXPORT_NAME.  */

        result = nbd_opt_go(ioc, info, errp);

        result = nbd_opt_info_or_go(ioc, NBD_OPT_GO, info, errp);

        if (result < 0) {

            return -EINVAL;

        }

nbd/trace-events

+4 −4
Original line number Diff line number Diff line
@@ -4,10 +4,10 @@ nbd_receive_option_reply(uint32_t option, const char *optname, uint32_t type, co 
nbd_server_error_msg(uint32_t err, const char *type, const char *msg) "server reported error 0x%" PRIx32 " (%s) with additional message: %s"

nbd_reply_err_unsup(uint32_t option, const char *name) "server doesn't understand request %" PRIu32 " (%s), attempting fallback"

nbd_receive_list(const char *name, const char *desc) "export list includes '%s', description '%s'"

nbd_opt_go_start(const char *name) "Attempting NBD_OPT_GO for export '%s'"

nbd_opt_go_success(void) "Export is good to go"

nbd_opt_go_info_unknown(int info, const char *name) "Ignoring unknown info %d (%s)"

nbd_opt_go_info_block_size(uint32_t minimum, uint32_t preferred, uint32_t maximum) "Block sizes are 0x%" PRIx32 ", 0x%" PRIx32 ", 0x%" PRIx32

nbd_opt_info_go_start(const char *opt, const char *name) "Attempting %s for export '%s'"

nbd_opt_info_go_success(const char *opt) "Export is ready after %s request"

nbd_opt_info_unknown(int info, const char *name) "Ignoring unknown info %d (%s)"

nbd_opt_info_block_size(uint32_t minimum, uint32_t preferred, uint32_t maximum) "Block sizes are 0x%" PRIx32 ", 0x%" PRIx32 ", 0x%" PRIx32

nbd_receive_query_exports_start(const char *wantname) "Querying export list for '%s'"

nbd_receive_query_exports_success(const char *wantname) "Found desired export name '%s'"

nbd_receive_starttls_new_client(void) "Setting up TLS"