Commit bbc8ea98 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

block-backend: Remember if attached device is non-qdev 



Almost all block devices are qdevified by now. This allows us to go back
from the BlockBackend to the DeviceState. xen_disk is the last device
that is missing. We'll remember in the BlockBackend if a xen_disk is
attached and can then disable any features that require going from a BB
to the DeviceState.

While at it, clearly mark the function used by xen_disk as legacy even
in its name, not just in TODO comments.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
parent 2bf7e10f

block/block-backend.c

+20 −8
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ struct BlockBackend { 
    BlockBackendPublic public;



    void *dev;                  /* attached device model, if any */

    bool legacy_dev;            /* true if dev is not a DeviceState */

    /* TODO change to DeviceState when all users are qdevified */

    const BlockDevOps *dev_ops;

    void *dev_opaque;
@@ -506,32 +507,38 @@ void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) 
    }

}



/*

 * Attach device model @dev to @blk.

 * Return 0 on success, -EBUSY when a device model is attached already.

 */

int blk_attach_dev(BlockBackend *blk, void *dev)

/* TODO change to DeviceState *dev when all users are qdevified */

static int blk_do_attach_dev(BlockBackend *blk, void *dev)

{

    if (blk->dev) {

        return -EBUSY;

    }

    blk_ref(blk);

    blk->dev = dev;

    blk->legacy_dev = false;

    blk_iostatus_reset(blk);

    return 0;

}



/*

 * Attach device model @dev to @blk.

 * Return 0 on success, -EBUSY when a device model is attached already.

 */

int blk_attach_dev(BlockBackend *blk, DeviceState *dev)

{

    return blk_do_attach_dev(blk, dev);

}



/*

 * Attach device model @dev to @blk.

 * @blk must not have a device model attached already.

 * TODO qdevified devices don't use this, remove when devices are qdevified

 */

void blk_attach_dev_nofail(BlockBackend *blk, void *dev)

void blk_attach_dev_legacy(BlockBackend *blk, void *dev)

{

    if (blk_attach_dev(blk, dev) < 0) {

    if (blk_do_attach_dev(blk, dev) < 0) {

        abort();

    }

    blk->legacy_dev = true;

}



/*
@@ -585,6 +592,11 @@ BlockBackend *blk_by_dev(void *dev) 
void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops,

                     void *opaque)

{

    /* All drivers that use blk_set_dev_ops() are qdevified and we want to keep

     * it that way, so we can assume blk->dev is a DeviceState if blk->dev_ops

     * is set. */

    assert(!blk->legacy_dev);



    blk->dev_ops = ops;

    blk->dev_opaque = opaque;

}

hw/block/xen_disk.c

+1 −1
Original line number Diff line number Diff line
@@ -1079,7 +1079,7 @@ static int blk_connect(struct XenDevice *xendev) 
         * so we can blk_unref() unconditionally */

        blk_ref(blkdev->blk);

    }

    blk_attach_dev_nofail(blkdev->blk, blkdev);

    blk_attach_dev_legacy(blkdev->blk, blkdev);

    blkdev->file_size = blk_getlength(blkdev->blk);

    if (blkdev->file_size < 0) {

        BlockDriverState *bs = blk_bs(blkdev->blk);

include/sysemu/block-backend.h

+2 −2
Original line number Diff line number Diff line
@@ -107,8 +107,8 @@ BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk); 
void blk_iostatus_disable(BlockBackend *blk);

void blk_iostatus_reset(BlockBackend *blk);

void blk_iostatus_set_err(BlockBackend *blk, int error);

int blk_attach_dev(BlockBackend *blk, void *dev);

void blk_attach_dev_nofail(BlockBackend *blk, void *dev);

int blk_attach_dev(BlockBackend *blk, DeviceState *dev);

void blk_attach_dev_legacy(BlockBackend *blk, void *dev);

void blk_detach_dev(BlockBackend *blk, void *dev);

void *blk_get_attached_dev(BlockBackend *blk);

BlockBackend *blk_by_dev(void *dev);