diff options
| -rw-r--r-- | block.c | 61 |
1 files changed, 44 insertions, 17 deletions
diff --git a/block.c b/block.c index f6e7cf4fb9..f06de58a3b 100644 --- a/block.c +++ b/block.c @@ -2375,21 +2375,21 @@ typedef struct BdrvReplaceChildState { BlockDriverState *old_bs; } BdrvReplaceChildState; -static void bdrv_replace_child_commit(void *opaque) +static void GRAPH_WRLOCK bdrv_replace_child_commit(void *opaque) { BdrvReplaceChildState *s = opaque; GLOBAL_STATE_CODE(); - bdrv_unref(s->old_bs); + bdrv_schedule_unref(s->old_bs); } -static void bdrv_replace_child_abort(void *opaque) +static void GRAPH_WRLOCK bdrv_replace_child_abort(void *opaque) { BdrvReplaceChildState *s = opaque; BlockDriverState *new_bs = s->child->bs; GLOBAL_STATE_CODE(); - bdrv_graph_wrlock(s->old_bs); + assert_bdrv_graph_writable(); /* old_bs reference is transparently moved from @s to @s->child */ if (!s->child->bs) { @@ -2408,7 +2408,6 @@ static void bdrv_replace_child_abort(void *opaque) assert(s->child->quiesced_parent); bdrv_replace_child_noperm(s->child, s->old_bs); - bdrv_graph_wrunlock(); bdrv_unref(new_bs); } @@ -2426,6 +2425,9 @@ static TransactionActionDrv bdrv_replace_child_drv = { * Both @child->bs and @new_bs (if non-NULL) must be drained. @new_bs must be * kept drained until the transaction is completed. * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. + * * The function doesn't update permissions, caller is responsible for this. */ static void GRAPH_WRLOCK @@ -2951,16 +2953,15 @@ typedef struct BdrvAttachChildCommonState { AioContext *old_child_ctx; } BdrvAttachChildCommonState; -static void bdrv_attach_child_common_abort(void *opaque) +static void GRAPH_WRLOCK bdrv_attach_child_common_abort(void *opaque) { BdrvAttachChildCommonState *s = opaque; BlockDriverState *bs = s->child->bs; GLOBAL_STATE_CODE(); + assert_bdrv_graph_writable(); - bdrv_graph_wrlock(NULL); bdrv_replace_child_noperm(s->child, NULL); - bdrv_graph_wrunlock(); if (bdrv_get_aio_context(bs) != s->old_child_ctx) { bdrv_try_change_aio_context(bs, s->old_child_ctx, NULL, &error_abort); @@ -2984,7 +2985,7 @@ static void bdrv_attach_child_common_abort(void *opaque) tran_commit(tran); } - bdrv_unref(bs); + bdrv_schedule_unref(bs); bdrv_child_free(s->child); } @@ -2998,6 +2999,9 @@ static TransactionActionDrv bdrv_attach_child_common_drv = { * * Function doesn't update permissions, caller is responsible for this. * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. + * * Returns new created child. * * The caller must hold the AioContext lock for @child_bs. Both @parent_bs and @@ -3114,6 +3118,9 @@ bdrv_attach_child_common(BlockDriverState *child_bs, * The caller must hold the AioContext lock for @child_bs. Both @parent_bs and * @child_bs can move to a different AioContext in this function. Callers must * make sure that their AioContext locking is still correct after this. + * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. */ static BdrvChild * GRAPH_WRLOCK bdrv_attach_child_noperm(BlockDriverState *parent_bs, @@ -3180,8 +3187,8 @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, ret = bdrv_refresh_perms(child_bs, tran, errp); out: - bdrv_graph_wrunlock(); tran_finalize(tran, ret); + bdrv_graph_wrunlock(); bdrv_unref(child_bs); @@ -3227,8 +3234,8 @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, } out: - bdrv_graph_wrunlock(); tran_finalize(tran, ret); + bdrv_graph_wrunlock(); bdrv_unref(child_bs); @@ -3393,6 +3400,9 @@ static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) * The caller must hold the AioContext lock for @child_bs. Both @parent_bs and * @child_bs can move to a different AioContext in this function. Callers must * make sure that their AioContext locking is still correct after this. + * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. */ static int GRAPH_WRLOCK bdrv_set_file_or_backing_noperm(BlockDriverState *parent_bs, @@ -3488,6 +3498,9 @@ out: * * If a backing child is already present (i.e. we're detaching a node), that * child node must be drained. + * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. */ static int GRAPH_WRLOCK bdrv_set_backing_noperm(BlockDriverState *bs, @@ -3519,8 +3532,8 @@ int bdrv_set_backing_hd_drained(BlockDriverState *bs, ret = bdrv_refresh_perms(bs, tran, errp); out: - bdrv_graph_wrunlock(); tran_finalize(tran, ret); + bdrv_graph_wrunlock(); return ret; } @@ -4594,7 +4607,9 @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) aio_context_release(ctx); } + bdrv_graph_wrlock(NULL); tran_commit(tran); + bdrv_graph_wrunlock(); QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) { BlockDriverState *bs = bs_entry->state.bs; @@ -4611,7 +4626,9 @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) goto cleanup; abort: + bdrv_graph_wrlock(NULL); tran_abort(tran); + bdrv_graph_wrunlock(); QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { if (bs_entry->prepared) { @@ -4678,6 +4695,9 @@ int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, * true and reopen_state->new_backing_bs contains a pointer to the new * backing BlockDriverState (or NULL). * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. + * * Return 0 on success, otherwise return < 0 and set @errp. * * The caller must hold the AioContext lock of @reopen_state->bs. @@ -4811,6 +4831,9 @@ static int bdrv_reopen_parse_file_or_backing(BDRVReopenState *reopen_state, * commit() for any other BDS that have been left in a prepare() state * * The caller must hold the AioContext lock of @reopen_state->bs. + * + * After calling this function, the transaction @change_child_tran may only be + * completed while holding a writer lock for the graph. */ static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, @@ -5262,6 +5285,9 @@ static TransactionActionDrv bdrv_remove_child_drv = { * Function doesn't update permissions, caller is responsible for this. * * @child->bs (if non-NULL) must be drained. + * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. */ static void GRAPH_WRLOCK bdrv_remove_child(BdrvChild *child, Transaction *tran) { @@ -5280,6 +5306,9 @@ static void GRAPH_WRLOCK bdrv_remove_child(BdrvChild *child, Transaction *tran) /* * Both @from and @to (if non-NULL) must be drained. @to must be kept drained * until the transaction is completed. + * + * After calling this function, the transaction @tran may only be completed + * while holding a writer lock for the graph. */ static int GRAPH_WRLOCK bdrv_replace_node_noperm(BlockDriverState *from, @@ -5386,8 +5415,8 @@ static int bdrv_replace_node_common(BlockDriverState *from, ret = 0; out: - bdrv_graph_wrunlock(); tran_finalize(tran, ret); + bdrv_graph_wrunlock(); bdrv_drained_end(to); bdrv_drained_end(from); @@ -5483,12 +5512,10 @@ int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, ret = bdrv_refresh_perms(bs_new, tran, errp); out: - bdrv_graph_wrunlock(); tran_finalize(tran, ret); - bdrv_graph_rdlock_main_loop(); bdrv_refresh_limits(bs_top, NULL, NULL); - bdrv_graph_rdunlock_main_loop(); + bdrv_graph_wrunlock(); bdrv_drained_end(bs_top); bdrv_drained_end(bs_new); @@ -5523,10 +5550,10 @@ int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs, refresh_list = g_slist_prepend(refresh_list, new_bs); ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp); - bdrv_graph_wrunlock(); tran_finalize(tran, ret); + bdrv_graph_wrunlock(); bdrv_drained_end(old_bs); bdrv_drained_end(new_bs); bdrv_unref(old_bs); |