Split out non-recursive parts, and refactor as block graph transaction action.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> --- block.c | 79 ++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 59 insertions(+), 20 deletions(-) diff --git a/block.c b/block.c index 0d0f065db4..e12acd5029 100644 --- a/block.c +++ b/block.c @@ -48,6 +48,7 @@ #include "qemu/timer.h" #include "qemu/cutils.h" #include "qemu/id.h" +#include "qemu/transactions.h" #include "block/coroutines.h" #ifdef CONFIG_BSD @@ -2011,6 +2012,61 @@ static void bdrv_child_perm(BlockDriverState *bs, BlockDriverState *child_bs, } } +static void bdrv_child_set_perm_commit(void *opaque) +{ + BdrvChild *c = opaque; + + c->has_backup_perm = false; +} + +static void bdrv_child_set_perm_abort(void *opaque) +{ + BdrvChild *c = opaque; + /* + * We may have child->has_backup_perm unset at this point, as in case of + * _check_ stage of permission update failure we may _check_ not the whole + * subtree. Still, _abort_ is called on the whole subtree anyway. + */ + if (c->has_backup_perm) { + c->perm = c->backup_perm; + c->shared_perm = c->backup_shared_perm; + c->has_backup_perm = false; + } +} + +static BdrvActionDrv bdrv_child_set_pem_drv = { + .abort = bdrv_child_set_perm_abort, + .commit = bdrv_child_set_perm_commit, +}; + +/* + * With tran=NULL needs to be followed by direct call to either + * bdrv_child_set_perm_commit() or bdrv_child_set_perm_abort(). + * + * With non-NUll tran needs to be followed by tran_abort() or tran_commit() + * instead. + */ +static void bdrv_child_set_perm_safe(BdrvChild *c, uint64_t perm, + uint64_t shared, GSList **tran) +{ + if (!c->has_backup_perm) { + c->has_backup_perm = true; + c->backup_perm = c->perm; + c->backup_shared_perm = c->shared_perm; + } + /* + * Note: it's OK if c->has_backup_perm was already set, as we can find the + * same c twice during check_perm procedure + */ + + c->perm = perm; + c->shared_perm = shared; + + if (tran) { + tran_prepend(tran, &bdrv_child_set_pem_drv, c); + } +} + /* * Check whether permissions on this node can be changed in a way that * @cumulative_perms and @cumulative_shared_perms are the new cumulative @@ -2276,37 +2332,20 @@ static int bdrv_child_check_perm(BdrvChild *c, BlockReopenQueue *q, return ret; } - if (!c->has_backup_perm) { - c->has_backup_perm = true; - c->backup_perm = c->perm; - c->backup_shared_perm = c->shared_perm; - } - /* - * Note: it's OK if c->has_backup_perm was already set, as we can find the - * same child twice during check_perm procedure - */ - - c->perm = perm; - c->shared_perm = shared; + bdrv_child_set_perm_safe(c, perm, shared, NULL); return 0; } static void bdrv_child_set_perm(BdrvChild *c) { - c->has_backup_perm = false; - + bdrv_child_set_perm_commit(c); bdrv_set_perm(c->bs); } static void bdrv_child_abort_perm_update(BdrvChild *c) { - if (c->has_backup_perm) { - c->perm = c->backup_perm; - c->shared_perm = c->backup_shared_perm; - c->has_backup_perm = false; - } - + bdrv_child_set_perm_abort(c); bdrv_abort_perm_update(c->bs); } -- 2.21.3