From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:32780) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YKrsO-0003Ec-Hp for qemu-devel@nongnu.org; Mon, 09 Feb 2015 12:12:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YKrsM-0006D7-P7 for qemu-devel@nongnu.org; Mon, 09 Feb 2015 12:12:00 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52642) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YKrsM-0006C3-I9 for qemu-devel@nongnu.org; Mon, 09 Feb 2015 12:11:58 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t19HBvbt003181 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Mon, 9 Feb 2015 12:11:58 -0500 From: Max Reitz Date: Mon, 9 Feb 2015 12:11:17 -0500 Message-Id: <1423501897-30410-18-git-send-email-mreitz@redhat.com> In-Reply-To: <1423501897-30410-1-git-send-email-mreitz@redhat.com> References: <1423501897-30410-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v2 17/37] block: Prepare remaining BB functions for NULL BDS List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Markus Armbruster , Max Reitz , Stefan Hajnoczi , John Snow There are several BlockBackend functions which, in theory, cannot fail. This patch makes them cope with the BlockDriverState pointer being NULL by making them fall back to some default action like ignoring the value in setters and returning the default in getters. Signed-off-by: Max Reitz --- block/block-backend.c | 76 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 60 insertions(+), 16 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index 524cf59..c3418f7 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -644,7 +644,11 @@ int64_t blk_getlength(BlockBackend *blk) void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr) { - bdrv_get_geometry(blk->bs, nb_sectors_ptr); + if (!blk->bs) { + *nb_sectors_ptr = 0; + } else { + bdrv_get_geometry(blk->bs, nb_sectors_ptr); + } } int64_t blk_nb_sectors(BlockBackend *blk) @@ -871,17 +875,27 @@ int blk_is_read_only(BlockBackend *blk) int blk_is_sg(BlockBackend *blk) { + if (!blk->bs) { + return 0; + } + return bdrv_is_sg(blk->bs); } int blk_enable_write_cache(BlockBackend *blk) { + if (!blk->bs) { + return 0; + } + return bdrv_enable_write_cache(blk->bs); } void blk_set_enable_write_cache(BlockBackend *blk, bool wce) { - bdrv_set_enable_write_cache(blk->bs, wce); + if (blk->bs) { + bdrv_set_enable_write_cache(blk->bs, wce); + } } void blk_invalidate_cache(BlockBackend *blk, Error **errp) @@ -906,12 +920,16 @@ bool blk_is_available(BlockBackend *blk) void blk_lock_medium(BlockBackend *blk, bool locked) { - bdrv_lock_medium(blk->bs, locked); + if (blk->bs) { + bdrv_lock_medium(blk->bs, locked); + } } void blk_eject(BlockBackend *blk, bool eject_flag) { - bdrv_eject(blk->bs, eject_flag); + if (blk->bs) { + bdrv_eject(blk->bs, eject_flag); + } } int blk_get_flags(BlockBackend *blk) @@ -925,7 +943,11 @@ int blk_get_flags(BlockBackend *blk) int blk_get_max_transfer_length(BlockBackend *blk) { - return blk->bs->bl.max_transfer_length; + if (blk->bs) { + return blk->bs->bl.max_transfer_length; + } else { + return 0; + } } void blk_set_guest_block_size(BlockBackend *blk, int align) @@ -940,22 +962,32 @@ void *blk_blockalign(BlockBackend *blk, size_t size) bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp) { + if (!blk->bs) { + return false; + } + return bdrv_op_is_blocked(blk->bs, op, errp); } void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason) { - bdrv_op_unblock(blk->bs, op, reason); + if (blk->bs) { + bdrv_op_unblock(blk->bs, op, reason); + } } void blk_op_block_all(BlockBackend *blk, Error *reason) { - bdrv_op_block_all(blk->bs, reason); + if (blk->bs) { + bdrv_op_block_all(blk->bs, reason); + } } void blk_op_unblock_all(BlockBackend *blk, Error *reason) { - bdrv_op_unblock_all(blk->bs, reason); + if (blk->bs) { + bdrv_op_unblock_all(blk->bs, reason); + } } AioContext *blk_get_aio_context(BlockBackend *blk) @@ -975,15 +1007,19 @@ static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb) void blk_set_aio_context(BlockBackend *blk, AioContext *new_context) { - bdrv_set_aio_context(blk->bs, new_context); + if (blk->bs) { + bdrv_set_aio_context(blk->bs, new_context); + } } void blk_add_aio_context_notifier(BlockBackend *blk, void (*attached_aio_context)(AioContext *new_context, void *opaque), void (*detach_aio_context)(void *opaque), void *opaque) { - bdrv_add_aio_context_notifier(blk->bs, attached_aio_context, - detach_aio_context, opaque); + if (blk->bs) { + bdrv_add_aio_context_notifier(blk->bs, attached_aio_context, + detach_aio_context, opaque); + } } void blk_remove_aio_context_notifier(BlockBackend *blk, @@ -992,23 +1028,31 @@ void blk_remove_aio_context_notifier(BlockBackend *blk, void (*detach_aio_context)(void *), void *opaque) { - bdrv_remove_aio_context_notifier(blk->bs, attached_aio_context, - detach_aio_context, opaque); + if (blk->bs) { + bdrv_remove_aio_context_notifier(blk->bs, attached_aio_context, + detach_aio_context, opaque); + } } void blk_add_close_notifier(BlockBackend *blk, Notifier *notify) { - bdrv_add_close_notifier(blk->bs, notify); + if (blk->bs) { + bdrv_add_close_notifier(blk->bs, notify); + } } void blk_io_plug(BlockBackend *blk) { - bdrv_io_plug(blk->bs); + if (blk->bs) { + bdrv_io_plug(blk->bs); + } } void blk_io_unplug(BlockBackend *blk) { - bdrv_io_unplug(blk->bs); + if (blk->bs) { + bdrv_io_unplug(blk->bs); + } } BlockAcctStats *blk_get_stats(BlockBackend *blk) -- 2.1.0