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=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 260C1C433E0 for ; Fri, 26 Jun 2020 14:55:00 +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 D439620775 for ; Fri, 26 Jun 2020 14:54:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="R2zcbjay" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D439620775 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]:35116 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jopkp-00047I-09 for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 10:54:59 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58192) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jopkG-0003fM-F1 for qemu-devel@nongnu.org; Fri, 26 Jun 2020 10:54:24 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:44285 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jopkE-00054n-3T for qemu-devel@nongnu.org; Fri, 26 Jun 2020 10:54:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593183260; 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: in-reply-to:in-reply-to:references:references; bh=sYlEFxBeJocIRhZr1JHEZXAuCklCWAKq2OP1HptvNcU=; b=R2zcbjayCoDsGljL2HQ9hxd844Ce5vfrjvg+foSiOHwpqPwvVug9jLhJ+IWRaItHTH7fAR 3beBAB/SVceMtkzitli0NvubPaQG2NJMQJ3AV19400ejov9B0uLsWoedKgGqjoQ8M7VrsU dnuizkKr/REcPIfniAjSAoeXHLhFplI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-450-ddKFdQ-9MUuNdO8mcfLwgg-1; Fri, 26 Jun 2020 10:54:15 -0400 X-MC-Unique: ddKFdQ-9MUuNdO8mcfLwgg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 255091B18BF0; Fri, 26 Jun 2020 14:54:13 +0000 (UTC) Received: from work-vm (ovpn-113-27.ams2.redhat.com [10.36.113.27]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 778F110013D2; Fri, 26 Jun 2020 14:54:02 +0000 (UTC) Date: Fri, 26 Jun 2020 15:54:00 +0100 From: "Dr. David Alan Gilbert" To: Alex Williamson Subject: Re: [PATCH QEMU v25 09/17] vfio: Add load state functions to SaveVMHandlers Message-ID: <20200626145400.GM3087@work-vm> References: <1592684486-18511-1-git-send-email-kwankhede@nvidia.com> <1592684486-18511-10-git-send-email-kwankhede@nvidia.com> <20200624125437.664869ce@x1.home> MIME-Version: 1.0 In-Reply-To: <20200624125437.664869ce@x1.home> User-Agent: Mutt/1.14.3 (2020-06-14) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=205.139.110.61; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 02:19:36 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action 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: cohuck@redhat.com, cjia@nvidia.com, aik@ozlabs.ru, Zhengxiao.zx@alibaba-inc.com, shuangtai.tst@alibaba-inc.com, qemu-devel@nongnu.org, peterx@redhat.com, Kirti Wankhede , eauger@redhat.com, yi.l.liu@intel.com, quintela@redhat.com, ziye.yang@intel.com, armbru@redhat.com, mlevitsk@redhat.com, pasic@linux.ibm.com, felipe@nutanix.com, zhi.a.wang@intel.com, kevin.tian@intel.com, yan.y.zhao@intel.com, changpeng.liu@intel.com, eskultet@redhat.com, Ken.Xue@amd.com, jonathan.davies@nutanix.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Alex Williamson (alex.williamson@redhat.com) wrote: > On Sun, 21 Jun 2020 01:51:18 +0530 > Kirti Wankhede wrote: > > > Sequence during _RESUMING device state: > > While data for this device is available, repeat below steps: > > a. read data_offset from where user application should write data. > > b. write data of data_size to migration region from data_offset. > > c. write data_size which indicates vendor driver that data is written in > > staging buffer. > > > > For user, data is opaque. User should write data in the same order as > > received. > > > > Signed-off-by: Kirti Wankhede > > Reviewed-by: Neo Jia > > Reviewed-by: Dr. David Alan Gilbert > > --- > > hw/vfio/migration.c | 177 +++++++++++++++++++++++++++++++++++++++++++++++++++ > > hw/vfio/trace-events | 3 + > > 2 files changed, 180 insertions(+) > > > > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > > index ef1150c1ff02..faacea5327cb 100644 > > --- a/hw/vfio/migration.c > > +++ b/hw/vfio/migration.c > > @@ -302,6 +302,33 @@ static int vfio_save_device_config_state(QEMUFile *f, void *opaque) > > return qemu_file_get_error(f); > > } > > > > +static int vfio_load_device_config_state(QEMUFile *f, void *opaque) > > +{ > > + VFIODevice *vbasedev = opaque; > > + uint64_t data; > > + > > + if (vbasedev->ops && vbasedev->ops->vfio_load_config) { > > + int ret; > > + > > + ret = vbasedev->ops->vfio_load_config(vbasedev, f); > > + if (ret) { > > + error_report("%s: Failed to load device config space", > > + vbasedev->name); > > + return ret; > > + } > > + } > > + > > + data = qemu_get_be64(f); > > + if (data != VFIO_MIG_FLAG_END_OF_STATE) { > > + error_report("%s: Failed loading device config space, " > > + "end flag incorrect 0x%"PRIx64, vbasedev->name, data); > > + return -EINVAL; > > + } > > + > > + trace_vfio_load_device_config_state(vbasedev->name); > > + return qemu_file_get_error(f); > > +} > > + > > /* ---------------------------------------------------------------------- */ > > > > static int vfio_save_setup(QEMUFile *f, void *opaque) > > @@ -472,12 +499,162 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) > > return ret; > > } > > > > +static int vfio_load_setup(QEMUFile *f, void *opaque) > > +{ > > + VFIODevice *vbasedev = opaque; > > + VFIOMigration *migration = vbasedev->migration; > > + int ret = 0; > > + > > + if (migration->region.mmaps) { > > + ret = vfio_region_mmap(&migration->region); > > + if (ret) { > > + error_report("%s: Failed to mmap VFIO migration region %d: %s", > > + vbasedev->name, migration->region.nr, > > + strerror(-ret)); > > + return ret; > > > Not fatal. > > > > + } > > + } > > + > > + ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_MASK, > > + VFIO_DEVICE_STATE_RESUMING); > > + if (ret) { > > + error_report("%s: Failed to set state RESUMING", vbasedev->name); > > + } > > + return ret; > > +} > > + > > +static int vfio_load_cleanup(void *opaque) > > +{ > > + vfio_save_cleanup(opaque); > > + return 0; > > +} > > + > > +static int vfio_load_state(QEMUFile *f, void *opaque, int version_id) > > +{ > > + VFIODevice *vbasedev = opaque; > > + VFIOMigration *migration = vbasedev->migration; > > + int ret = 0; > > + uint64_t data, data_size; > > + > > + data = qemu_get_be64(f); > > + while (data != VFIO_MIG_FLAG_END_OF_STATE) { > > + > > + trace_vfio_load_state(vbasedev->name, data); > > + > > + switch (data) { > > + case VFIO_MIG_FLAG_DEV_CONFIG_STATE: > > + { > > + ret = vfio_load_device_config_state(f, opaque); > > + if (ret) { > > + return ret; > > + } > > + break; > > + } > > + case VFIO_MIG_FLAG_DEV_SETUP_STATE: > > + { > > + data = qemu_get_be64(f); > > + if (data == VFIO_MIG_FLAG_END_OF_STATE) { > > + return ret; > > + } else { > > + error_report("%s: SETUP STATE: EOS not found 0x%"PRIx64, > > + vbasedev->name, data); > > + return -EINVAL; > > This is essentially just a compatibility failure, right? For instance > some future version of QEMU might include additional data between these > markers that we don't understand and therefore we fail the migration. Or any other screwup in data layout; we've found having a canary at the end of state is quite useful for when we screwup for one reason or another. Dave > Thanks, > > Alex > > > + } > > + break; > > + } > > + case VFIO_MIG_FLAG_DEV_DATA_STATE: > > + { > > + VFIORegion *region = &migration->region; > > + uint64_t data_offset = 0, size; > > + > > + data_size = size = qemu_get_be64(f); > > + if (data_size == 0) { > > + break; > > + } > > + > > + ret = pread(vbasedev->fd, &data_offset, sizeof(data_offset), > > + region->fd_offset + > > + offsetof(struct vfio_device_migration_info, > > + data_offset)); > > + if (ret != sizeof(data_offset)) { > > + error_report("%s:Failed to get migration buffer data offset %d", > > + vbasedev->name, ret); > > + return -EINVAL; > > + } > > + > > + trace_vfio_load_state_device_data(vbasedev->name, data_offset, > > + data_size); > > + > > + while (size) { > > + void *buf = NULL; > > + uint64_t sec_size; > > + bool buffer_mmaped; > > + > > + buf = get_data_section_size(region, data_offset, size, > > + &sec_size); > > + > > + buffer_mmaped = (buf != NULL); > > + > > + if (!buffer_mmaped) { > > + buf = g_try_malloc(sec_size); > > + if (!buf) { > > + error_report("%s: Error allocating buffer ", __func__); > > + return -ENOMEM; > > + } > > + } > > + > > + qemu_get_buffer(f, buf, sec_size); > > + > > + if (!buffer_mmaped) { > > + ret = pwrite(vbasedev->fd, buf, sec_size, > > + region->fd_offset + data_offset); > > + g_free(buf); > > + > > + if (ret != sec_size) { > > + error_report("%s: Failed to set migration buffer %d", > > + vbasedev->name, ret); > > + return -EINVAL; > > + } > > + } > > + size -= sec_size; > > + data_offset += sec_size; > > + } > > + > > + ret = pwrite(vbasedev->fd, &data_size, sizeof(data_size), > > + region->fd_offset + > > + offsetof(struct vfio_device_migration_info, data_size)); > > + if (ret != sizeof(data_size)) { > > + error_report("%s: Failed to set migration buffer data size %d", > > + vbasedev->name, ret); > > + return -EINVAL; > > + } > > + break; > > + } > > + > > + default: > > + error_report("%s: Unknown tag 0x%"PRIx64, vbasedev->name, data); > > + return -EINVAL; > > + } > > + > > + data = qemu_get_be64(f); > > + ret = qemu_file_get_error(f); > > + if (ret) { > > + return ret; > > + } > > + } > > + > > + return ret; > > +} > > + > > static SaveVMHandlers savevm_vfio_handlers = { > > .save_setup = vfio_save_setup, > > .save_cleanup = vfio_save_cleanup, > > .save_live_pending = vfio_save_pending, > > .save_live_iterate = vfio_save_iterate, > > .save_live_complete_precopy = vfio_save_complete_precopy, > > + .load_setup = vfio_load_setup, > > + .load_cleanup = vfio_load_cleanup, > > + .load_state = vfio_load_state, > > }; > > > > /* ---------------------------------------------------------------------- */ > > diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events > > index 9a1c5e17d97f..4a4bd3ba9a2a 100644 > > --- a/hw/vfio/trace-events > > +++ b/hw/vfio/trace-events > > @@ -157,3 +157,6 @@ vfio_save_device_config_state(const char *name) " (%s)" > > vfio_save_pending(const char *name, uint64_t precopy, uint64_t postcopy, uint64_t compatible) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64" compatible 0x%"PRIx64 > > vfio_save_iterate(const char *name, int data_size) " (%s) data_size %d" > > vfio_save_complete_precopy(const char *name) " (%s)" > > +vfio_load_device_config_state(const char *name) " (%s)" > > +vfio_load_state(const char *name, uint64_t data) " (%s) data 0x%"PRIx64 > > +vfio_load_state_device_data(const char *name, uint64_t data_offset, uint64_t data_size) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK