Commit 6c2e581d authored by Kevin Wolf's avatar Kevin Wolf
Browse files

nbd: Support auto-read-only option 



If read-only=off, but auto-read-only=on is given, open a read-write NBD
connection if the server provides a read-write export, but instead of
erroring out for read-only exports, just degrade to read-only.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
parent eaa2410f

block/nbd-client.c

+5 −5
Original line number Diff line number Diff line
@@ -992,11 +992,11 @@ int nbd_client_init(BlockDriverState *bs, 
        logout("Failed to negotiate with the NBD server\n");

        return ret;

    }

    if (client->info.flags & NBD_FLAG_READ_ONLY &&

        !bdrv_is_read_only(bs)) {

        error_setg(errp,

                   "request for write access conflicts with read-only export");

        return -EACCES;

    if (client->info.flags & NBD_FLAG_READ_ONLY) {

        ret = bdrv_apply_auto_read_only(bs, "NBD export is read-only", errp);

        if (ret < 0) {

            return ret;

        }

    }

    if (client->info.flags & NBD_FLAG_SEND_FUA) {

        bs->supported_write_flags = BDRV_REQ_FUA;