Commit 981776b3 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

block: Add permissions to BlockBackend 



The BlockBackend can now store the permissions that its user requires.
This is necessary because nodes can be ejected from or inserted into a
BlockBackend and all of these operations must make sure that the user
still gets what it requested initially.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Acked-by: default avatarFam Zheng <famz@redhat.com>
parent f68c598b

block/block-backend.c

+27 −0
Original line number Diff line number Diff line
@@ -59,6 +59,9 @@ struct BlockBackend { 
    bool iostatus_enabled;

    BlockDeviceIoStatus iostatus;



    uint64_t perm;

    uint64_t shared_perm;



    bool allow_write_beyond_eof;



    NotifierList remove_bs_notifiers, insert_bs_notifiers;
@@ -126,6 +129,8 @@ BlockBackend *blk_new(void) 


    blk = g_new0(BlockBackend, 1);

    blk->refcnt = 1;

    blk->perm = 0;

    blk->shared_perm = BLK_PERM_ALL;

    blk_set_enable_write_cache(blk, true);



    qemu_co_queue_init(&blk->public.throttled_reqs[0]);
@@ -511,6 +516,27 @@ void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) 
    }

}



/*

 * Sets the permission bitmasks that the user of the BlockBackend needs.

 */

int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm,

                 Error **errp)

{

    int ret;



    if (blk->root) {

        ret = bdrv_child_try_set_perm(blk->root, perm, shared_perm, errp);

        if (ret < 0) {

            return ret;

        }

    }



    blk->perm = perm;

    blk->shared_perm = shared_perm;



    return 0;

}



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

{

    if (blk->dev) {
@@ -557,6 +583,7 @@ void blk_detach_dev(BlockBackend *blk, void *dev) 
    blk->dev_ops = NULL;

    blk->dev_opaque = NULL;

    blk->guest_block_size = 512;

    blk_set_perm(blk, 0, BLK_PERM_ALL, &error_abort);

    blk_unref(blk);

}

include/sysemu/block-backend.h

+2 −0
Original line number Diff line number Diff line
@@ -105,6 +105,8 @@ void blk_remove_bs(BlockBackend *blk); 
void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs);

bool bdrv_has_blk(BlockDriverState *bs);

bool bdrv_is_root_node(BlockDriverState *bs);

int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm,

                 Error **errp);



void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow);

void blk_iostatus_enable(BlockBackend *blk);