Commit bd745e23 authored by Max Reitz's avatar Max Reitz Committed by Kevin Wolf
Browse files

blockdev: Allow more options for BB-less BDS tree 



Most of the options which blockdev_init() parses for both the
BlockBackend and the root BDS are valid for just the root BDS as well
(e.g. read-only). This patch allows specifying these options even if not
creating a BlockBackend.

Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent fbf8175e

blockdev.c

+91 −6
Original line number Diff line number Diff line
@@ -614,6 +614,54 @@ err_no_opts: 
    return NULL;

}



static QemuOptsList qemu_root_bds_opts;



/* Takes the ownership of bs_opts */

static BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp)

{

    BlockDriverState *bs;

    QemuOpts *opts;

    Error *local_error = NULL;

    BlockdevDetectZeroesOptions detect_zeroes;

    int ret;

    int bdrv_flags = 0;



    opts = qemu_opts_create(&qemu_root_bds_opts, NULL, 1, errp);

    if (!opts) {

        goto fail;

    }



    qemu_opts_absorb_qdict(opts, bs_opts, &local_error);

    if (local_error) {

        error_propagate(errp, local_error);

        goto fail;

    }



    extract_common_blockdev_options(opts, &bdrv_flags, NULL, NULL,

                                    &detect_zeroes, &local_error);

    if (local_error) {

        error_propagate(errp, local_error);

        goto fail;

    }



    bs = NULL;

    ret = bdrv_open(&bs, NULL, NULL, bs_opts, bdrv_flags, errp);

    if (ret < 0) {

        goto fail_no_bs_opts;

    }



    bs->detect_zeroes = detect_zeroes;



fail_no_bs_opts:

    qemu_opts_del(opts);

    return bs;



fail:

    qemu_opts_del(opts);

    QDECREF(bs_opts);

    return NULL;

}



static void qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,

                            Error **errp)

{
@@ -3171,18 +3219,14 @@ void qmp_blockdev_add(BlockdevOptions *options, Error **errp) 


        bs = blk_bs(blk);

    } else {

        int ret;



        if (!qdict_get_try_str(qdict, "node-name")) {

            error_setg(errp, "'id' and/or 'node-name' need to be specified for "

                       "the root node");

            goto fail;

        }



        bs = NULL;

        ret = bdrv_open(&bs, NULL, NULL, qdict, BDRV_O_RDWR | BDRV_O_CACHE_WB,

                        errp);

        if (ret < 0) {

        bs = bds_tree_init(qdict, errp);

        if (!bs) {

            goto fail;

        }

    }
@@ -3337,6 +3381,47 @@ QemuOptsList qemu_common_drive_opts = { 
    },

};



static QemuOptsList qemu_root_bds_opts = {

    .name = "root-bds",

    .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),

    .desc = {

        {

            .name = "discard",

            .type = QEMU_OPT_STRING,

            .help = "discard operation (ignore/off, unmap/on)",

        },{

            .name = "cache.writeback",

            .type = QEMU_OPT_BOOL,

            .help = "enables writeback mode for any caches",

        },{

            .name = "cache.direct",

            .type = QEMU_OPT_BOOL,

            .help = "enables use of O_DIRECT (bypass the host page cache)",

        },{

            .name = "cache.no-flush",

            .type = QEMU_OPT_BOOL,

            .help = "ignore any flush requests for the device",

        },{

            .name = "aio",

            .type = QEMU_OPT_STRING,

            .help = "host AIO implementation (threads, native)",

        },{

            .name = "read-only",

            .type = QEMU_OPT_BOOL,

            .help = "open drive file as read-only",

        },{

            .name = "copy-on-read",

            .type = QEMU_OPT_BOOL,

            .help = "copy read data from backing file into image file",

        },{

            .name = "detect-zeroes",

            .type = QEMU_OPT_STRING,

            .help = "try to optimize zero writes (off, on, unmap)",

        },

        { /* end of list */ }

    },

};



QemuOptsList qemu_drive_opts = {

    .name = "drive",

    .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),