From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56908) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YsSxv-00048R-5e for qemu-devel@nongnu.org; Wed, 13 May 2015 05:28:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YsSxq-0001fg-QA for qemu-devel@nongnu.org; Wed, 13 May 2015 05:28:35 -0400 From: Fam Zheng Date: Wed, 13 May 2015 17:28:10 +0000 Message-Id: <1431538099-3286-3-git-send-email-famz@redhat.com> In-Reply-To: <1431538099-3286-1-git-send-email-famz@redhat.com> References: <1431538099-3286-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v2 02/11] block: Add op blocker notifier list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , qemu-block@nongnu.org, jcody@redhat.com, armbru@redhat.com, mreitz@redhat.com, Stefan Hajnoczi , pbonzini@redhat.com BDS users can register a notifier and get notified about op blocker changes. Signed-off-by: Fam Zheng --- block.c | 28 ++++++++++++++++++++++++++++ include/block/block.h | 8 ++++++++ include/block/block_int.h | 3 +++ 3 files changed, 39 insertions(+) diff --git a/block.c b/block.c index 7904098..cb47308 100644 --- a/block.c +++ b/block.c @@ -3375,6 +3375,12 @@ struct BdrvOpBlocker { QLIST_ENTRY(BdrvOpBlocker) list; }; +void bdrv_op_blocker_add_notifier(BlockDriverState *bs, + Notifier *notifier) +{ + notifier_list_add(&bs->op_blocker_notifiers, notifier); +} + bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp) { BdrvOpBlocker *blocker; @@ -3391,26 +3397,48 @@ bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp) return false; } +static void bdrv_op_blocker_notify(BlockDriverState *bs, BlockOpType op, + Error *reason, bool blocking) +{ + BlockOpEvent event = (BlockOpEvent) { + op = op, + reason = reason, + blocking = true, + }; + + notifier_list_notify(&bs->op_blocker_notifiers, &event); +} + void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason) { + bool blocked; BdrvOpBlocker *blocker; assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); blocker = g_new0(BdrvOpBlocker, 1); blocker->reason = reason; + blocked = !QLIST_EMPTY(&bs->op_blockers[op]); QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list); + if (!blocked) { + bdrv_op_blocker_notify(bs, op, reason, true); + } } void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason) { + bool blocked; BdrvOpBlocker *blocker, *next; assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); + blocked = !QLIST_EMPTY(&bs->op_blockers[op]); QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) { if (blocker->reason == reason) { QLIST_REMOVE(blocker, list); g_free(blocker); } } + if (blocked && QLIST_EMPTY(&bs->op_blockers[op])) { + bdrv_op_blocker_notify(bs, op, reason, false); + } } void bdrv_op_block_all(BlockDriverState *bs, Error *reason) diff --git a/include/block/block.h b/include/block/block.h index 906fb31..3420b2c 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -163,6 +163,12 @@ typedef enum BlockOpType { BLOCK_OP_TYPE_MAX, } BlockOpType; +typedef struct { + BlockOpType type; + Error *reason; + bool blocking; +} BlockOpEvent; + void bdrv_iostatus_enable(BlockDriverState *bs); void bdrv_iostatus_reset(BlockDriverState *bs); void bdrv_iostatus_disable(BlockDriverState *bs); @@ -491,6 +497,8 @@ void bdrv_disable_copy_on_read(BlockDriverState *bs); void bdrv_ref(BlockDriverState *bs); void bdrv_unref(BlockDriverState *bs); +void bdrv_op_blocker_add_notifier(BlockDriverState *bs, + Notifier *notifier); bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); diff --git a/include/block/block_int.h b/include/block/block_int.h index db29b74..29d1c84 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -418,6 +418,9 @@ struct BlockDriverState { /* operation blockers */ QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX]; + /* Callback when one list in op_blockers has "empty" status change. */ + NotifierList op_blocker_notifiers; + /* long-running background operation */ BlockJob *job; -- 2.4.0