{"id":814196,"url":"http://patchwork.ozlabs.org/api/1.2/patches/814196/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20170915101008.16646-5-kwolf@redhat.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.2/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20170915101008.16646-5-kwolf@redhat.com>","list_archive_url":null,"date":"2017-09-15T10:10:06","name":"[4/6] block: Base permissions on rw state after reopen","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"64cb1202e0da35b9d5407ea8d7349cc6982e885c","submitter":{"id":2714,"url":"http://patchwork.ozlabs.org/api/1.2/people/2714/?format=json","name":"Kevin Wolf","email":"kwolf@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20170915101008.16646-5-kwolf@redhat.com/mbox/","series":[{"id":3264,"url":"http://patchwork.ozlabs.org/api/1.2/series/3264/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=3264","date":"2017-09-15T10:10:02","name":"block: Fix permissions after ro/rw reopen","version":1,"mbox":"http://patchwork.ozlabs.org/series/3264/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/814196/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/814196/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ext-mx03.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx03.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=kwolf@redhat.com"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xtrny0YzRz9sxR\n\tfor ;\n\tFri, 15 Sep 2017 20:13:26 +1000 (AEST)","from localhost ([::1]:52348 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dsnci-0005AP-3T\n\tfor incoming@patchwork.ozlabs.org; Fri, 15 Sep 2017 06:13:24 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:37326)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dsnZw-0002Dm-Cv\n\tfor qemu-devel@nongnu.org; Fri, 15 Sep 2017 06:10:35 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dsnZr-0004N2-Ms\n\tfor qemu-devel@nongnu.org; Fri, 15 Sep 2017 06:10:32 -0400","from mx1.redhat.com ([209.132.183.28]:46816)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from )\n\tid 1dsnZn-0004Gq-1d; Fri, 15 Sep 2017 06:10:23 -0400","from smtp.corp.redhat.com\n\t(int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby mx1.redhat.com (Postfix) with ESMTPS id 274F880F79;\n\tFri, 15 Sep 2017 10:10:22 +0000 (UTC)","from localhost.localdomain.com (ovpn-117-157.ams2.redhat.com\n\t[10.36.117.157])\n\tby smtp.corp.redhat.com (Postfix) with ESMTP id DFDB971C4D;\n\tFri, 15 Sep 2017 10:10:20 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com 274F880F79","From":"Kevin Wolf ","To":"qemu-block@nongnu.org","Date":"Fri, 15 Sep 2017 12:10:06 +0200","Message-Id":"<20170915101008.16646-5-kwolf@redhat.com>","In-Reply-To":"<20170915101008.16646-1-kwolf@redhat.com>","References":"<20170915101008.16646-1-kwolf@redhat.com>","X-Scanned-By":"MIMEDefang 2.79 on 10.5.11.16","X-Greylist":"Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.27]);\n\tFri, 15 Sep 2017 10:10:22 +0000 (UTC)","X-detected-operating-system":"by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic]\n\t[fuzzy]","X-Received-From":"209.132.183.28","Subject":"[Qemu-devel] [PATCH 4/6] block: Base permissions on rw state after\n\treopen","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Cc":"kwolf@redhat.com, famz@redhat.com, qemu-devel@nongnu.org,\n\tmreitz@redhat.com","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"},"content":"When new permissions are calculated during bdrv_reopen(), they need to\nbe based on the state of the graph as it will be after the reopen has\ncompleted, not on the current state of the involved nodes.\n\nThis patch makes bdrv_is_writable() optionally accept a BlockReopenQueue\nfrom which the new flags are taken. This is then used for determining\nthe new bs->file permissions of format drivers as soon as we add the\ncode to actually pass a non-NULL reopen queue to the .bdrv_child_perm\ncallbacks.\n\nWhile moving bdrv_is_writable(), make it static. It isn't used outside\nblock.c.\n\nSigned-off-by: Kevin Wolf \n---\n include/block/block.h | 1 -\n block.c | 52 ++++++++++++++++++++++++++++++++++++---------------\n 2 files changed, 37 insertions(+), 16 deletions(-)","diff":"diff --git a/include/block/block.h b/include/block/block.h\nindex 2ad18775af..082eb2cd9c 100644\n--- a/include/block/block.h\n+++ b/include/block/block.h\n@@ -435,7 +435,6 @@ int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,\n int64_t offset, int64_t bytes, int64_t *pnum);\n \n bool bdrv_is_read_only(BlockDriverState *bs);\n-bool bdrv_is_writable(BlockDriverState *bs);\n int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only,\n bool ignore_allow_rdw, Error **errp);\n int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp);\ndiff --git a/block.c b/block.c\nindex 0b499fda4c..ed8d51dd42 100644\n--- a/block.c\n+++ b/block.c\n@@ -239,12 +239,6 @@ bool bdrv_is_read_only(BlockDriverState *bs)\n return bs->read_only;\n }\n \n-/* Returns whether the image file can be written to right now */\n-bool bdrv_is_writable(BlockDriverState *bs)\n-{\n- return !bdrv_is_read_only(bs) && !(bs->open_flags & BDRV_O_INACTIVE);\n-}\n-\n int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only,\n bool ignore_allow_rdw, Error **errp)\n {\n@@ -1537,6 +1531,41 @@ static int bdrv_child_check_perm(BdrvChild *c, BlockReopenQueue *q,\n static void bdrv_child_abort_perm_update(BdrvChild *c);\n static void bdrv_child_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared);\n \n+typedef struct BlockReopenQueueEntry {\n+ bool prepared;\n+ BDRVReopenState state;\n+ QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry;\n+} BlockReopenQueueEntry;\n+\n+/*\n+ * Return the flags that @bs will have after the reopens in @q have\n+ * successfully completed. If @q is NULL (or @bs is not contained in @q),\n+ * return the current flags.\n+ */\n+static int bdrv_reopen_get_flags(BlockReopenQueue *q, BlockDriverState *bs)\n+{\n+ BlockReopenQueueEntry *entry;\n+\n+ if (q != NULL) {\n+ QSIMPLEQ_FOREACH(entry, q, entry) {\n+ if (entry->state.bs == bs) {\n+ return entry->state.flags;\n+ }\n+ }\n+ }\n+\n+ return bs->open_flags;\n+}\n+\n+/* Returns whether the image file can be written to after the reopen queue @q\n+ * has been successfully applied, or right now if @q is NULL. */\n+static bool bdrv_is_writable(BlockDriverState *bs, BlockReopenQueue *q)\n+{\n+ int flags = bdrv_reopen_get_flags(q, bs);\n+\n+ return (flags & (BDRV_O_RDWR | BDRV_O_INACTIVE)) == BDRV_O_RDWR;\n+}\n+\n static void bdrv_child_perm(BlockDriverState *bs, BlockDriverState *child_bs,\n BdrvChild *c, const BdrvChildRole *role,\n BlockReopenQueue *reopen_queue,\n@@ -1574,7 +1603,7 @@ static int bdrv_check_perm(BlockDriverState *bs, BlockReopenQueue *q,\n \n /* Write permissions never work with read-only images */\n if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) &&\n- !bdrv_is_writable(bs))\n+ !bdrv_is_writable(bs, q))\n {\n error_setg(errp, \"Block node is read-only\");\n return -EPERM;\n@@ -1864,8 +1893,7 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,\n &perm, &shared);\n \n /* Format drivers may touch metadata even if the guest doesn't write */\n- /* TODO Take flags from reopen_queue */\n- if (bdrv_is_writable(bs)) {\n+ if (bdrv_is_writable(bs, reopen_queue)) {\n perm |= BLK_PERM_WRITE | BLK_PERM_RESIZE;\n }\n \n@@ -2642,12 +2670,6 @@ BlockDriverState *bdrv_open(const char *filename, const char *reference,\n NULL, errp);\n }\n \n-typedef struct BlockReopenQueueEntry {\n- bool prepared;\n- BDRVReopenState state;\n- QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry;\n-} BlockReopenQueueEntry;\n-\n /*\n * Adds a BlockDriverState to a simple queue for an atomic, transactional\n * reopen of multiple devices.\n","prefixes":["4/6"]}