Commit ca2e2144 authored by Fam Zheng's avatar Fam Zheng Committed by Eric Blake
Browse files

block-backend: Allow more "can inactivate" cases 



These two conditions corresponds to mirror job's source and target,
which need to be allowed as they are part of the non-shared storage
migration workflow: failing to inactivate either will result in a
failure during migration completion.

Signed-off-by: default avatarFam Zheng <famz@redhat.com>
Message-Id: <20170823134242.12080-3-famz@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
[eblake: improve comment grammar]
Signed-off-by: default avatarEric Blake <eblake@redhat.com>
parent c16de8f5

block/block-backend.c

+17 −5
Original line number Diff line number Diff line
@@ -70,6 +70,7 @@ struct BlockBackend { 


    int quiesce_counter;

    VMChangeStateEntry *vmsh;

    bool force_allow_inactivate;

};



typedef struct BlockBackendAIOCB {
@@ -192,17 +193,28 @@ static void blk_root_activate(BdrvChild *child, Error **errp) 
    }

}



void blk_set_force_allow_inactivate(BlockBackend *blk)

{

    blk->force_allow_inactivate = true;

}



static bool blk_can_inactivate(BlockBackend *blk)

{

    /* Only inactivate BlockBackends for guest devices (which are inactive at

     * this point because the VM is stopped) and unattached monitor-owned

     * BlockBackends. If there is still any other user like a block job, then

     * we simply can't inactivate the image. */

    /* If it is a guest device, inactivate is ok. */

    if (blk->dev || blk_name(blk)[0]) {

        return true;

    }



    return false;

    /* Inactivating means no more writes to the image can be done,

     * even if those writes would be changes invisible to the

     * guest.  For block job BBs that satisfy this, we can just allow

     * it.  This is the case for mirror job source, which is required

     * by libvirt non-shared block migration. */

    if (!(blk->perm & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED))) {

        return true;

    }



    return blk->force_allow_inactivate;

}



static int blk_root_inactivate(BdrvChild *child)

include/sysemu/block-backend.h

+1 −0
Original line number Diff line number Diff line
@@ -241,5 +241,6 @@ void blk_set_io_limits(BlockBackend *blk, ThrottleConfig *cfg); 
void blk_io_limits_disable(BlockBackend *blk);

void blk_io_limits_enable(BlockBackend *blk, const char *group);

void blk_io_limits_update_group(BlockBackend *blk, const char *group);

void blk_set_force_allow_inactivate(BlockBackend *blk);



#endif