From patchwork Thu Mar 28 16:40:26 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 232127 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 7F1FE2C00A2 for ; Fri, 29 Mar 2013 03:58:34 +1100 (EST) Received: from localhost ([::1]:32985 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ULFv4-00082V-3r for incoming@patchwork.ozlabs.org; Thu, 28 Mar 2013 12:43:18 -0400 Received: from eggs.gnu.org ([208.118.235.92]:46547) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ULFt6-0005oE-8T for qemu-devel@nongnu.org; Thu, 28 Mar 2013 12:41:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ULFt2-0002ER-De for qemu-devel@nongnu.org; Thu, 28 Mar 2013 12:41:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55829) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ULFt2-0002EJ-3c for qemu-devel@nongnu.org; Thu, 28 Mar 2013 12:41:12 -0400 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 r2SGfBIV025098 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 28 Mar 2013 12:41:11 -0400 Received: from localhost (ovpn-112-23.ams2.redhat.com [10.36.112.23]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r2SGfAjK022497; Thu, 28 Mar 2013 12:41:10 -0400 From: Stefan Hajnoczi To: Date: Thu, 28 Mar 2013 17:40:26 +0100 Message-Id: <1364488837-15916-13-git-send-email-stefanha@redhat.com> In-Reply-To: <1364488837-15916-1-git-send-email-stefanha@redhat.com> References: <1364488837-15916-1-git-send-email-stefanha@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Kevin Wolf , Anthony Liguori , Stefan Hajnoczi Subject: [Qemu-devel] [PATCH 12/23] qcow2: Finalise interface of handle_alloc() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Kevin Wolf The interface works completely on a byte granularity now and duplicated parameters are removed. Signed-off-by: Kevin Wolf Signed-off-by: Stefan Hajnoczi --- block/qcow2-cluster.c | 29 ++++++++++++++++------------- block/qcow2.h | 5 +++++ 2 files changed, 21 insertions(+), 13 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 8f4ef0d..8ed1f7d 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -875,13 +875,9 @@ static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset, * newly allocated cluster. * * -errno: in error cases - * - * TODO Get rid of n_start, n_end - * TODO Make *bytes actually behave as specified above */ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, - uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m, - int n_start, int n_end) + uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m) { BDRVQcowState *s = bs->opaque; int l2_index; @@ -901,8 +897,11 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, * Calculate the number of clusters to look for. We stop at L2 table * boundaries to keep things simple. */ + nb_clusters = + size_to_clusters(s, offset_into_cluster(s, guest_offset) + *bytes); + l2_index = offset_to_l2_index(s, guest_offset); - nb_clusters = MIN(size_to_clusters(s, *bytes), s->l2_size - l2_index); + nb_clusters = MIN(nb_clusters, s->l2_size - l2_index); /* Find L2 entry for the first involved cluster */ ret = get_cluster_table(bs, guest_offset, &l2_table, &l2_index); @@ -954,10 +953,13 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, * newly allocated cluster to the end of the aread that the write * request actually writes to (excluding COW at the end) */ - int requested_sectors = n_end; + int requested_sectors = + (*bytes + offset_into_cluster(s, guest_offset)) + >> BDRV_SECTOR_BITS; int avail_sectors = nb_clusters << (s->cluster_bits - BDRV_SECTOR_BITS); - int alloc_n_start = *host_offset == 0 ? n_start : 0; + int alloc_n_start = offset_into_cluster(s, guest_offset) + >> BDRV_SECTOR_BITS; int nb_sectors = MIN(requested_sectors, avail_sectors); if (*host_offset == 0) { @@ -984,7 +986,9 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, qemu_co_queue_init(&(*m)->dependent_requests); QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); - *bytes = nb_clusters * s->cluster_size; + *bytes = MIN(*bytes, (nb_sectors * BDRV_SECTOR_SIZE) + - offset_into_cluster(s, guest_offset)); + assert(*bytes != 0); } else { *bytes = 0; return 0; @@ -1139,10 +1143,9 @@ again: alloc_n_end = n_end; } - cur_bytes = nb_clusters * s->cluster_size; + cur_bytes = MIN(cur_bytes, ((alloc_n_end - alloc_n_start) << BDRV_SECTOR_BITS)); - ret = handle_alloc(bs, offset, &cluster_offset, &cur_bytes, m, - alloc_n_start, alloc_n_end); + ret = handle_alloc(bs, offset, &cluster_offset, &cur_bytes, m); if (ret < 0) { return ret; } @@ -1150,7 +1153,7 @@ again: if (!*host_offset) { *host_offset = cluster_offset; } - nb_clusters = size_to_clusters(s, cur_bytes); + nb_clusters = size_to_clusters(s, cur_bytes + offset_into_cluster(s, offset)); /* Some cleanup work */ done: diff --git a/block/qcow2.h b/block/qcow2.h index c4eaf67..32806bd 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -271,6 +271,11 @@ static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset) return offset & ~(s->cluster_size - 1); } +static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset) +{ + return offset & (s->cluster_size - 1); +} + static inline int size_to_clusters(BDRVQcowState *s, int64_t size) { return (size + (s->cluster_size - 1)) >> s->cluster_bits;