From patchwork Thu Aug 10 17:37:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 13349763 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 0EE70C001DE for ; Thu, 10 Aug 2023 17:45:17 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qU9gE-00045R-HM; Thu, 10 Aug 2023 13:42:38 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qU9gA-00041w-55 for qemu-devel@nongnu.org; Thu, 10 Aug 2023 13:42:34 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qU9g6-000511-S4 for qemu-devel@nongnu.org; Thu, 10 Aug 2023 13:42:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1691689350; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JfWfQay1QhwVSoZ1XCnHsphs7KmgDAF9TUmLE2L8eq0=; b=BoAZWPvw7Qzjk26OfRWWPbFrqh6iMj5r50F/B/ag0/CKfFnYYlH/Jj4tEI2LpvZTE/QIgX Z1OrJuZBIR/LHCqveQu/l3pH6Hcv/wwpgJq8whgSP2LIySEdBc+gqpJtnQH5DqzH2LAvq8 jKaHYLD6fFpDeVlHLZDyqBnP+ZAOhao= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-488-SS5gWB1ZP96rbSRJEVp_2A-1; Thu, 10 Aug 2023 13:42:26 -0400 X-MC-Unique: SS5gWB1ZP96rbSRJEVp_2A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7CEC33C11C67; Thu, 10 Aug 2023 17:42:26 +0000 (UTC) Received: from green.redhat.com (unknown [10.2.16.169]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0A9001121314; Thu, 10 Aug 2023 17:42:25 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, vsementsov@yandex-team.ru, Kevin Wolf , Hanna Reitz Subject: [PATCH v5 13/17] nbd/client: Accept 64-bit block status chunks Date: Thu, 10 Aug 2023 12:37:00 -0500 Message-ID: <20230810173646.17695-32-eblake@redhat.com> In-Reply-To: <20230810173646.17695-19-eblake@redhat.com> References: <20230810173646.17695-19-eblake@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Once extended mode is enabled, we need to accept 64-bit status replies (even for replies that don't exceed a 32-bit length). It is easier to normalize narrow replies into wide format so that the rest of our code only has to handle one width. Although a server is non-compliant if it sends a 64-bit reply in compact mode, or a 32-bit reply in extended mode, it is still easy enough to tolerate these mismatches. In normal execution, we are only requesting "base:allocation" which never exceeds 32 bits for flag values. But during testing with x-dirty-bitmap, we can force qemu to connect to some other context that might have 64-bit status bit; however, we ignore those upper bits (other than mapping qemu:allocation-depth into something that 'qemu-img map --output=json' can expose), and since that only affects testing, we really don't bother with checking whether more than the two least-significant bits are set. Signed-off-by: Eric Blake Reviewed-by: Vladimir Sementsov-Ogievskiy --- v5: factor out duplicate length calculation [Vladimir], add R-b v4: tweak comments and error message about count mismatch, fix setting of wide in loop [Vladimir] --- block/nbd.c | 49 ++++++++++++++++++++++++++++++++-------------- block/trace-events | 1 + 2 files changed, 35 insertions(+), 15 deletions(-) diff --git a/block/nbd.c b/block/nbd.c index d60782b25c7..d37f5425a0f 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -616,13 +616,17 @@ static int nbd_parse_offset_hole_payload(BDRVNBDState *s, */ static int nbd_parse_blockstatus_payload(BDRVNBDState *s, NBDStructuredReplyChunk *chunk, - uint8_t *payload, uint64_t orig_length, - NBDExtent32 *extent, Error **errp) + uint8_t *payload, bool wide, + uint64_t orig_length, + NBDExtent64 *extent, Error **errp) { uint32_t context_id; + uint32_t count; + size_t ext_len = wide ? sizeof(*extent) : sizeof(NBDExtent32); + size_t pay_len = sizeof(context_id) + wide * sizeof(count) + ext_len; /* The server succeeded, so it must have sent [at least] one extent */ - if (chunk->length < sizeof(context_id) + sizeof(*extent)) { + if (chunk->length < pay_len) { error_setg(errp, "Protocol error: invalid payload for " "NBD_REPLY_TYPE_BLOCK_STATUS"); return -EINVAL; @@ -637,8 +641,15 @@ static int nbd_parse_blockstatus_payload(BDRVNBDState *s, return -EINVAL; } - extent->length = payload_advance32(&payload); - extent->flags = payload_advance32(&payload); + if (wide) { + count = payload_advance32(&payload); + extent->length = payload_advance64(&payload); + extent->flags = payload_advance64(&payload); + } else { + count = 0; + extent->length = payload_advance32(&payload); + extent->flags = payload_advance32(&payload); + } if (extent->length == 0) { error_setg(errp, "Protocol error: server sent status chunk with " @@ -659,7 +670,7 @@ static int nbd_parse_blockstatus_payload(BDRVNBDState *s, * (always a safe status, even if it loses information). */ if (s->info.min_block && !QEMU_IS_ALIGNED(extent->length, - s->info.min_block)) { + s->info.min_block)) { trace_nbd_parse_blockstatus_compliance("extent length is unaligned"); if (extent->length > s->info.min_block) { extent->length = QEMU_ALIGN_DOWN(extent->length, @@ -673,13 +684,15 @@ static int nbd_parse_blockstatus_payload(BDRVNBDState *s, /* * We used NBD_CMD_FLAG_REQ_ONE, so the server should not have * sent us any more than one extent, nor should it have included - * status beyond our request in that extent. However, it's easy - * enough to ignore the server's noncompliance without killing the + * status beyond our request in that extent. Furthermore, a wide + * server should have replied with an accurate count (we left + * count at 0 for a narrow server). However, it's easy enough to + * ignore the server's noncompliance without killing the * connection; just ignore trailing extents, and clamp things to * the length of our request. */ - if (chunk->length > sizeof(context_id) + sizeof(*extent)) { - trace_nbd_parse_blockstatus_compliance("more than one extent"); + if (count != wide || chunk->length > pay_len) { + trace_nbd_parse_blockstatus_compliance("unexpected extent count"); } if (extent->length > orig_length) { extent->length = orig_length; @@ -1125,7 +1138,7 @@ nbd_co_receive_cmdread_reply(BDRVNBDState *s, uint64_t cookie, static int coroutine_fn nbd_co_receive_blockstatus_reply(BDRVNBDState *s, uint64_t cookie, - uint64_t length, NBDExtent32 *extent, + uint64_t length, NBDExtent64 *extent, int *request_ret, Error **errp) { NBDReplyChunkIter iter; @@ -1138,11 +1151,17 @@ nbd_co_receive_blockstatus_reply(BDRVNBDState *s, uint64_t cookie, NBD_FOREACH_REPLY_CHUNK(s, iter, cookie, false, NULL, &reply, &payload) { int ret; NBDStructuredReplyChunk *chunk = &reply.structured; + bool wide; assert(nbd_reply_is_structured(&reply)); switch (chunk->type) { + case NBD_REPLY_TYPE_BLOCK_STATUS_EXT: case NBD_REPLY_TYPE_BLOCK_STATUS: + wide = chunk->type == NBD_REPLY_TYPE_BLOCK_STATUS_EXT; + if ((s->info.mode >= NBD_MODE_EXTENDED) != wide) { + trace_nbd_extended_headers_compliance("block_status"); + } if (received) { nbd_channel_error(s, -EINVAL); error_setg(&local_err, "Several BLOCK_STATUS chunks in reply"); @@ -1150,9 +1169,9 @@ nbd_co_receive_blockstatus_reply(BDRVNBDState *s, uint64_t cookie, } received = true; - ret = nbd_parse_blockstatus_payload(s, &reply.structured, - payload, length, extent, - &local_err); + ret = nbd_parse_blockstatus_payload( + s, &reply.structured, payload, wide, + length, extent, &local_err); if (ret < 0) { nbd_channel_error(s, ret); nbd_iter_channel_error(&iter, ret, &local_err); @@ -1382,7 +1401,7 @@ static int coroutine_fn GRAPH_RDLOCK nbd_client_co_block_status( int64_t *pnum, int64_t *map, BlockDriverState **file) { int ret, request_ret; - NBDExtent32 extent = { 0 }; + NBDExtent64 extent = { 0 }; BDRVNBDState *s = (BDRVNBDState *)bs->opaque; Error *local_err = NULL; diff --git a/block/trace-events b/block/trace-events index 925aa554bbf..8e789e1f12f 100644 --- a/block/trace-events +++ b/block/trace-events @@ -166,6 +166,7 @@ iscsi_xcopy(void *src_lun, uint64_t src_off, void *dst_lun, uint64_t dst_off, ui # nbd.c nbd_parse_blockstatus_compliance(const char *err) "ignoring extra data from non-compliant server: %s" nbd_structured_read_compliance(const char *type) "server sent non-compliant unaligned read %s chunk" +nbd_extended_headers_compliance(const char *type) "server sent non-compliant %s chunk not matching choice of extended headers" nbd_read_reply_entry_fail(int ret, const char *err) "ret = %d, err: %s" nbd_co_request_fail(uint64_t from, uint64_t len, uint64_t handle, uint16_t flags, uint16_t type, const char *name, int ret, const char *err) "Request failed { .from = %" PRIu64", .len = %" PRIu64 ", .handle = %" PRIu64 ", .flags = 0x%" PRIx16 ", .type = %" PRIu16 " (%s) } ret = %d, err: %s" nbd_client_handshake(const char *export_name) "export '%s'"