From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81C6DC31E46 for ; Wed, 12 Jun 2019 22:43:47 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 546BC20B7C for ; Wed, 12 Jun 2019 22:43:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 546BC20B7C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35636 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBy6-000589-BU for qemu-devel@archiver.kernel.org; Wed, 12 Jun 2019 18:43:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46082) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hbBSq-0008Nt-HY for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:11:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hbBSo-00089J-BR for qemu-devel@nongnu.org; Wed, 12 Jun 2019 18:11:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45442) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hbBSg-00083M-Ql; Wed, 12 Jun 2019 18:11:22 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id EC67030C31A4; Wed, 12 Jun 2019 22:11:16 +0000 (UTC) Received: from localhost (unknown [10.40.205.72]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4ABF75DEDF; Wed, 12 Jun 2019 22:11:16 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Thu, 13 Jun 2019 00:09:49 +0200 Message-Id: <20190612221004.2317-28-mreitz@redhat.com> In-Reply-To: <20190612221004.2317-1-mreitz@redhat.com> References: <20190612221004.2317-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Wed, 12 Jun 2019 22:11:16 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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 v5 27/42] commit: Deal with filters X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This includes some permission limiting (for example, we only need to take the RESIZE permission if the base is smaller than the top). Signed-off-by: Max Reitz --- block/block-backend.c | 16 ++++--- block/commit.c | 97 ++++++++++++++++++++++++++++++++----------- blockdev.c | 6 ++- 3 files changed, 87 insertions(+), 32 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index f5d9407d20..227a6951a0 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -2156,11 +2156,17 @@ int blk_commit_all(void) AioContext *aio_context =3D blk_get_aio_context(blk); =20 aio_context_acquire(aio_context); - if (blk_is_inserted(blk) && blk->root->bs->backing) { - int ret =3D bdrv_commit(blk->root->bs); - if (ret < 0) { - aio_context_release(aio_context); - return ret; + if (blk_is_inserted(blk)) { + BlockDriverState *non_filter; + + /* Legacy function, so skip implicit filters */ + non_filter =3D bdrv_skip_implicit_filters(blk->root->bs); + if (bdrv_filtered_cow_child(non_filter)) { + int ret =3D bdrv_commit(non_filter); + if (ret < 0) { + aio_context_release(aio_context); + return ret; + } } } aio_context_release(aio_context); diff --git a/block/commit.c b/block/commit.c index f20a26fecd..ec5a8c8edf 100644 --- a/block/commit.c +++ b/block/commit.c @@ -112,7 +112,7 @@ static void commit_abort(Job *job) * something to base, the intermediate images aren't valid any more.= */ bdrv_child_try_set_perm(s->commit_top_bs->backing, 0, BLK_PERM_ALL, &error_abort); - bdrv_replace_node(s->commit_top_bs, backing_bs(s->commit_top_bs), + bdrv_replace_node(s->commit_top_bs, s->commit_top_bs->backing->bs, &error_abort); =20 bdrv_unref(s->commit_top_bs); @@ -137,6 +137,7 @@ static void commit_clean(Job *job) static int coroutine_fn commit_run(Job *job, Error **errp) { CommitBlockJob *s =3D container_of(job, CommitBlockJob, common.job); + BlockDriverState *filtered_base; int64_t offset; uint64_t delay_ns =3D 0; int ret =3D 0; @@ -163,6 +164,9 @@ static int coroutine_fn commit_run(Job *job, Error **= errp) } } =20 + filtered_base =3D bdrv_filtered_cow_bs(bdrv_find_overlay(blk_bs(s->t= op), + blk_bs(s->bas= e))); + buf =3D blk_blockalign(s->top, COMMIT_BUFFER_SIZE); =20 for (offset =3D 0; offset < len; offset +=3D n) { @@ -176,7 +180,7 @@ static int coroutine_fn commit_run(Job *job, Error **= errp) break; } /* Copy if allocated above the base */ - ret =3D bdrv_is_allocated_above(blk_bs(s->top), blk_bs(s->base), + ret =3D bdrv_is_allocated_above(blk_bs(s->top), filtered_base, offset, COMMIT_BUFFER_SIZE, &n); copy =3D (ret =3D=3D 1); trace_commit_one_iteration(s, offset, n, ret); @@ -269,15 +273,35 @@ void commit_start(const char *job_id, BlockDriverSt= ate *bs, CommitBlockJob *s; BlockDriverState *iter; BlockDriverState *commit_top_bs =3D NULL; + BlockDriverState *filtered_base; Error *local_err =3D NULL; + int64_t base_size, top_size; + uint64_t perms, iter_shared_perms; int ret; =20 assert(top !=3D bs); - if (top =3D=3D base) { + if (bdrv_skip_rw_filters(top) =3D=3D bdrv_skip_rw_filters(base)) { error_setg(errp, "Invalid files for merge: top and base are the = same"); return; } =20 + base_size =3D bdrv_getlength(base); + if (base_size < 0) { + error_setg_errno(errp, -base_size, "Could not inquire base image= size"); + return; + } + + top_size =3D bdrv_getlength(top); + if (top_size < 0) { + error_setg_errno(errp, -top_size, "Could not inquire top image s= ize"); + return; + } + + perms =3D BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE; + if (base_size < top_size) { + perms |=3D BLK_PERM_RESIZE; + } + s =3D block_job_create(job_id, &commit_job_driver, NULL, bs, 0, BLK_= PERM_ALL, speed, creation_flags, NULL, NULL, errp); if (!s) { @@ -313,17 +337,43 @@ void commit_start(const char *job_id, BlockDriverSt= ate *bs, =20 s->commit_top_bs =3D commit_top_bs; =20 - /* Block all nodes between top and base, because they will - * disappear from the chain after this operation. */ + /* + * Block all nodes between top and base, because they will + * disappear from the chain after this operation. + * Note that this assumes that the user is fine with removing all + * nodes (including R/W filters) between top and base. Assuring + * this is the responsibility of the interface (i.e. whoever calls + * commit_start()). + */ assert(bdrv_chain_contains(top, base)); - for (iter =3D top; iter !=3D base; iter =3D backing_bs(iter)) { - /* XXX BLK_PERM_WRITE needs to be allowed so we don't block ours= elves - * at s->base (if writes are blocked for a node, they are also b= locked - * for its backing file). The other options would be a second fi= lter - * driver above s->base. */ + + /* + * The topmost node with + * bdrv_skip_rw_filters(filtered_base) =3D=3D bdrv_skip_rw_filters(b= ase) + */ + filtered_base =3D bdrv_filtered_cow_bs(bdrv_find_overlay(top, base))= ; + + assert(bdrv_skip_rw_filters(filtered_base) =3D=3D bdrv_skip_rw_filte= rs(base)); + + /* + * XXX BLK_PERM_WRITE needs to be allowed so we don't block ourselve= s + * at s->base (if writes are blocked for a node, they are also block= ed + * for its backing file). The other options would be a second filter + * driver above s->base. + */ + iter_shared_perms =3D BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE; + + for (iter =3D top; iter !=3D base; iter =3D bdrv_filtered_bs(iter)) = { + if (iter =3D=3D filtered_base) { + /* + * From here on, all nodes are filters on the base. This + * allows us to share BLK_PERM_CONSISTENT_READ. + */ + iter_shared_perms |=3D BLK_PERM_CONSISTENT_READ; + } + ret =3D block_job_add_bdrv(&s->common, "intermediate node", iter= , 0, - BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRI= TE, - errp); + iter_shared_perms, errp); if (ret < 0) { goto fail; } @@ -340,9 +390,7 @@ void commit_start(const char *job_id, BlockDriverStat= e *bs, } =20 s->base =3D blk_new(s->common.job.aio_context, - BLK_PERM_CONSISTENT_READ - | BLK_PERM_WRITE - | BLK_PERM_RESIZE, + perms, BLK_PERM_CONSISTENT_READ | BLK_PERM_GRAPH_MOD | BLK_PERM_WRITE_UNCHANGED); @@ -408,19 +456,22 @@ int bdrv_commit(BlockDriverState *bs) if (!drv) return -ENOMEDIUM; =20 - if (!bs->backing) { + backing_file_bs =3D bdrv_filtered_cow_bs(bs); + + if (!backing_file_bs) { return -ENOTSUP; } =20 if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, NULL) || - bdrv_op_is_blocked(bs->backing->bs, BLOCK_OP_TYPE_COMMIT_TARGET,= NULL)) { + bdrv_op_is_blocked(backing_file_bs, BLOCK_OP_TYPE_COMMIT_TARGET,= NULL)) + { return -EBUSY; } =20 - ro =3D bs->backing->bs->read_only; + ro =3D backing_file_bs->read_only; =20 if (ro) { - if (bdrv_reopen_set_read_only(bs->backing->bs, false, NULL)) { + if (bdrv_reopen_set_read_only(backing_file_bs, false, NULL)) { return -EACCES; } } @@ -436,8 +487,6 @@ int bdrv_commit(BlockDriverState *bs) } =20 /* Insert commit_top block node above backing, so we can write to it= */ - backing_file_bs =3D backing_bs(bs); - commit_top_bs =3D bdrv_new_open_driver(&bdrv_commit_top, NULL, BDRV_= O_RDWR, &local_err); if (commit_top_bs =3D=3D NULL) { @@ -522,15 +571,13 @@ ro_cleanup: qemu_vfree(buf); =20 blk_unref(backing); - if (backing_file_bs) { - bdrv_set_backing_hd(bs, backing_file_bs, &error_abort); - } + bdrv_set_backing_hd(bs, backing_file_bs, &error_abort); bdrv_unref(commit_top_bs); blk_unref(src); =20 if (ro) { /* ignoring error return here */ - bdrv_reopen_set_read_only(bs->backing->bs, true, NULL); + bdrv_reopen_set_read_only(backing_file_bs, true, NULL); } =20 return ret; diff --git a/blockdev.c b/blockdev.c index 605e7b0994..5036d064d4 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1095,7 +1095,7 @@ void hmp_commit(Monitor *mon, const QDict *qdict) return; } =20 - bs =3D blk_bs(blk); + bs =3D bdrv_skip_implicit_filters(blk_bs(blk)); aio_context =3D bdrv_get_aio_context(bs); aio_context_acquire(aio_context); =20 @@ -3392,7 +3392,9 @@ void qmp_block_commit(bool has_job_id, const char *= job_id, const char *device, =20 assert(bdrv_get_aio_context(base_bs) =3D=3D aio_context); =20 - for (iter =3D top_bs; iter !=3D backing_bs(base_bs); iter =3D backin= g_bs(iter)) { + for (iter =3D top_bs; iter !=3D bdrv_filtered_bs(base_bs); + iter =3D bdrv_filtered_bs(iter)) + { if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp))= { goto out; } --=20 2.21.0