From patchwork Tue Jun 7 09:20:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 9160181 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D012F60467 for ; Tue, 7 Jun 2016 09:21:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B877C20410 for ; Tue, 7 Jun 2016 09:21:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AC33D269A3; Tue, 7 Jun 2016 09:21:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id E99F920410 for ; Tue, 7 Jun 2016 09:21:19 +0000 (UTC) Received: from localhost ([::1]:48001 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bADCI-0003p4-Ne for patchwork-qemu-devel@patchwork.kernel.org; Tue, 07 Jun 2016 05:21:18 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48411) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bADBz-0003nZ-1i for qemu-devel@nongnu.org; Tue, 07 Jun 2016 05:21:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bADBv-0000AM-S1 for qemu-devel@nongnu.org; Tue, 07 Jun 2016 05:20:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47933) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bADBo-00007R-8K; Tue, 07 Jun 2016 05:20:48 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8F06137E64; Tue, 7 Jun 2016 09:20:47 +0000 (UTC) Received: from noname.str.redhat.com. (dhcp-192-197.str.redhat.com [10.33.192.197]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u579KjZU005698; Tue, 7 Jun 2016 05:20:46 -0400 From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 7 Jun 2016 11:20:39 +0200 Message-Id: <1465291239-12576-1-git-send-email-kwolf@redhat.com> In-Reply-To: <575643D7.3090807@redhat.com> References: <575643D7.3090807@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Tue, 07 Jun 2016 09:20:47 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 3/5] qcow2: Make copy_sectors() byte based X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, jsnow@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP This will allow copy on write operations where the overwritten part of the cluster is not aligned to sector boundaries. Also rename the function because it has nothing to do with sectors any more. Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake --- block/qcow2-cluster.c | 55 +++++++++++++++++++++++++-------------------------- 1 file changed, 27 insertions(+), 28 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index c5b739e..1e3f7f0 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -390,22 +390,18 @@ int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num, return 0; } -static int coroutine_fn copy_sectors(BlockDriverState *bs, - uint64_t start_sect, - uint64_t cluster_offset, - int n_start, int n_end) +static int coroutine_fn do_perform_cow(BlockDriverState *bs, + uint64_t src_cluster_offset, + uint64_t cluster_offset, + int offset_in_cluster, + int bytes) { BDRVQcow2State *s = bs->opaque; QEMUIOVector qiov; struct iovec iov; - int n, ret; - - n = n_end - n_start; - if (n <= 0) { - return 0; - } + int ret; - iov.iov_len = n * BDRV_SECTOR_SIZE; + iov.iov_len = bytes; iov.iov_base = qemu_try_blockalign(bs, iov.iov_len); if (iov.iov_base == NULL) { return -ENOMEM; @@ -424,18 +420,21 @@ static int coroutine_fn copy_sectors(BlockDriverState *bs, * interface. This avoids double I/O throttling and request tracking, * which can lead to deadlock when block layer copy-on-read is enabled. */ - ret = bs->drv->bdrv_co_preadv(bs, (start_sect + n_start) * BDRV_SECTOR_SIZE, - n * BDRV_SECTOR_SIZE, &qiov, 0); + ret = bs->drv->bdrv_co_preadv(bs, src_cluster_offset + offset_in_cluster, + bytes, &qiov, 0); if (ret < 0) { goto out; } if (bs->encrypted) { Error *err = NULL; + int64_t sector = (cluster_offset + offset_in_cluster) + >> BDRV_SECTOR_BITS; assert(s->cipher); - if (qcow2_encrypt_sectors(s, start_sect + n_start, - iov.iov_base, iov.iov_base, n, - true, &err) < 0) { + assert((offset_in_cluster & ~BDRV_SECTOR_MASK) == 0); + assert((bytes & ~BDRV_SECTOR_MASK) == 0); + if (qcow2_encrypt_sectors(s, sector, iov.iov_base, iov.iov_base, + bytes >> BDRV_SECTOR_BITS, true, &err) < 0) { ret = -EIO; error_free(err); goto out; @@ -443,14 +442,14 @@ static int coroutine_fn copy_sectors(BlockDriverState *bs, } ret = qcow2_pre_write_overlap_check(bs, 0, - cluster_offset + n_start * BDRV_SECTOR_SIZE, n * BDRV_SECTOR_SIZE); + cluster_offset + offset_in_cluster, bytes); if (ret < 0) { goto out; } BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE); - ret = bdrv_co_writev(bs->file->bs, (cluster_offset >> 9) + n_start, n, - &qiov); + ret = bdrv_co_pwritev(bs->file->bs, cluster_offset + offset_in_cluster, + bytes, &qiov, 0); if (ret < 0) { goto out; } @@ -745,9 +744,8 @@ static int perform_cow(BlockDriverState *bs, QCowL2Meta *m, Qcow2COWRegion *r) } qemu_co_mutex_unlock(&s->lock); - ret = copy_sectors(bs, m->offset / BDRV_SECTOR_SIZE, m->alloc_offset, - r->offset / BDRV_SECTOR_SIZE, - r->offset / BDRV_SECTOR_SIZE + r->nb_sectors); + ret = do_perform_cow(bs, m->offset, m->alloc_offset, + r->offset, r->nb_sectors * BDRV_SECTOR_SIZE); qemu_co_mutex_lock(&s->lock); if (ret < 0) { @@ -809,13 +807,14 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m) assert(l2_index + m->nb_clusters <= s->l2_size); for (i = 0; i < m->nb_clusters; i++) { /* if two concurrent writes happen to the same unallocated cluster - * each write allocates separate cluster and writes data concurrently. - * The first one to complete updates l2 table with pointer to its - * cluster the second one has to do RMW (which is done above by - * copy_sectors()), update l2 table with its cluster pointer and free - * old cluster. This is what this loop does */ - if(l2_table[l2_index + i] != 0) + * each write allocates separate cluster and writes data concurrently. + * The first one to complete updates l2 table with pointer to its + * cluster the second one has to do RMW (which is done above by + * perform_cow()), update l2 table with its cluster pointer and free + * old cluster. This is what this loop does */ + if (l2_table[l2_index + i] != 0) { old_cluster[j++] = l2_table[l2_index + i]; + } l2_table[l2_index + i] = cpu_to_be64((cluster_offset + (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);