From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:38330) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Th1QB-0002uj-Kr for qemu-devel@nongnu.org; Fri, 07 Dec 2012 12:09:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Th1Q6-0007ZM-Ec for qemu-devel@nongnu.org; Fri, 07 Dec 2012 12:09:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53825) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Th1Q6-0007ZH-7D for qemu-devel@nongnu.org; Fri, 07 Dec 2012 12:09:02 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id qB7H91Yr014906 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 7 Dec 2012 12:09:01 -0500 From: Kevin Wolf Date: Fri, 7 Dec 2012 18:08:49 +0100 Message-Id: <1354900129-5745-9-git-send-email-kwolf@redhat.com> In-Reply-To: <1354900129-5745-1-git-send-email-kwolf@redhat.com> References: <1354900129-5745-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH 8/8] qcow2: Factor out handle_dependencies() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com Signed-off-by: Kevin Wolf --- block/qcow2-cluster.c | 70 +++++++++++++++++++++++++++++------------------- 1 files changed, 42 insertions(+), 28 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 7a038ac..468ef1b 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -753,38 +753,16 @@ out: } /* - * Allocates new clusters for the given guest_offset. - * - * At most *nb_clusters are allocated, and on return *nb_clusters is updated to - * contain the number of clusters that have been allocated and are contiguous - * in the image file. - * - * If *host_offset is non-zero, it specifies the offset in the image file at - * which the new clusters must start. *nb_clusters can be 0 on return in this - * case if the cluster at host_offset is already in use. If *host_offset is - * zero, the clusters can be allocated anywhere in the image file. - * - * *host_offset is updated to contain the offset into the image file at which - * the first allocated cluster starts. - * - * Return 0 on success and -errno in error cases. -EAGAIN means that the - * function has been waiting for another request and the allocation must be - * restarted, but the whole request should not be failed. + * Check if there already is an AIO write request in flight which allocates + * the same cluster. In this case we need to wait until the previous + * request has completed and updated the L2 table accordingly. */ -static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset, - uint64_t *host_offset, unsigned int *nb_clusters) +static int handle_dependencies(BlockDriverState *bs, uint64_t guest_offset, + unsigned int *nb_clusters) { BDRVQcowState *s = bs->opaque; QCowL2Meta *old_alloc; - trace_qcow2_do_alloc_clusters_offset(qemu_coroutine_self(), guest_offset, - *host_offset, *nb_clusters); - - /* - * Check if there already is an AIO write request in flight which allocates - * the same cluster. In this case we need to wait until the previous - * request has completed and updated the L2 table accordingly. - */ QLIST_FOREACH(old_alloc, &s->cluster_allocs, next_in_flight) { uint64_t start = guest_offset >> s->cluster_bits; @@ -817,6 +795,42 @@ static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset, abort(); } + return 0; +} + +/* + * Allocates new clusters for the given guest_offset. + * + * At most *nb_clusters are allocated, and on return *nb_clusters is updated to + * contain the number of clusters that have been allocated and are contiguous + * in the image file. + * + * If *host_offset is non-zero, it specifies the offset in the image file at + * which the new clusters must start. *nb_clusters can be 0 on return in this + * case if the cluster at host_offset is already in use. If *host_offset is + * zero, the clusters can be allocated anywhere in the image file. + * + * *host_offset is updated to contain the offset into the image file at which + * the first allocated cluster starts. + * + * Return 0 on success and -errno in error cases. -EAGAIN means that the + * function has been waiting for another request and the allocation must be + * restarted, but the whole request should not be failed. + */ +static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset, + uint64_t *host_offset, unsigned int *nb_clusters) +{ + BDRVQcowState *s = bs->opaque; + int ret; + + trace_qcow2_do_alloc_clusters_offset(qemu_coroutine_self(), guest_offset, + *host_offset, *nb_clusters); + + ret = handle_dependencies(bs, guest_offset, nb_clusters); + if (ret < 0) { + return ret; + } + /* Allocate new clusters */ trace_qcow2_cluster_alloc_phys(qemu_coroutine_self()); if (*host_offset == 0) { @@ -828,7 +842,7 @@ static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset, *host_offset = cluster_offset; return 0; } else { - int ret = qcow2_alloc_clusters_at(bs, *host_offset, *nb_clusters); + ret = qcow2_alloc_clusters_at(bs, *host_offset, *nb_clusters); if (ret < 0) { return ret; } -- 1.7.6.5