From patchwork Mon Aug 26 18:55:49 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kirti Wankhede X-Patchwork-Id: 1153413 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=nvidia.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=nvidia.com header.i=@nvidia.com header.b="Al4KfOsy"; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 46HMX94Bvpz9sBp for ; Tue, 27 Aug 2019 05:29:44 +1000 (AEST) Received: from localhost ([::1]:56944 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i2KgO-0005yT-Vn for incoming@patchwork.ozlabs.org; Mon, 26 Aug 2019 15:29:41 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39372) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i2KbW-0000Ev-Gi for qemu-devel@nongnu.org; Mon, 26 Aug 2019 15:24:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i2KbU-0000XE-OS for qemu-devel@nongnu.org; Mon, 26 Aug 2019 15:24:38 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:15364) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i2KbU-0000WY-Dt for qemu-devel@nongnu.org; Mon, 26 Aug 2019 15:24:36 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate14.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Mon, 26 Aug 2019 12:24:35 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Mon, 26 Aug 2019 12:24:35 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Mon, 26 Aug 2019 12:24:35 -0700 Received: from HQMAIL105.nvidia.com (172.20.187.12) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Mon, 26 Aug 2019 19:24:34 +0000 Received: from kwankhede-dev.nvidia.com (10.124.1.5) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Mon, 26 Aug 2019 19:24:28 +0000 From: Kirti Wankhede To: , Date: Tue, 27 Aug 2019 00:25:49 +0530 Message-ID: <1566845753-18993-10-git-send-email-kwankhede@nvidia.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1566845753-18993-1-git-send-email-kwankhede@nvidia.com> References: <1566845753-18993-1-git-send-email-kwankhede@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1566847475; bh=M9Q0ah+X2tAQ1Njs3pr2RnO3ZV1hwsEl51ZfD088844=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:X-NVConfidentiality:MIME-Version: Content-Type; b=Al4KfOsynOjJ9l5y+PcrkTIbO5RpmKU5dXpPsjrp3z5CmH/+6TJ9HCrtxx4OZ74zi 6rrjAeHIErV5Be5zsClUSnIbSJhG80DDLtt89ziyK//gwYYRXaBh+CEo3+TL0TKqup 1GXX9CcKs+vqEwn/GnihISG8UzF6u8BephZlpDusuhyiAUegwKz0h5aqSoj9OxxbvA UHMGTc9IFfzSad5SrwFAXPsOkAljqCsr8zhdypS86QLyli29uDYeyJqa6ePlgbqn1f 5gIRokfCHjDCq13tSn1Gs3jBQtTr1bgI25esMsTkoRhiqYtB8M7tjs9w4CpytvZUNU jSgxOVQ6sxQ/A== X-detected-operating-system: by eggs.gnu.org: Windows 7 or 8 X-Received-From: 216.228.121.143 Subject: [Qemu-devel] [PATCH v8 09/13] vfio: Add save state functions to SaveVMHandlers 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: Zhengxiao.zx@Alibaba-inc.com, kevin.tian@intel.com, yi.l.liu@intel.com, yan.y.zhao@intel.com, eskultet@redhat.com, ziye.yang@intel.com, qemu-devel@nongnu.org, cohuck@redhat.com, shuangtai.tst@alibaba-inc.com, dgilbert@redhat.com, zhi.a.wang@intel.com, mlevitsk@redhat.com, pasic@linux.ibm.com, aik@ozlabs.ru, Kirti Wankhede , eauger@redhat.com, felipe@nutanix.com, jonathan.davies@nutanix.com, changpeng.liu@intel.com, Ken.Xue@amd.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Added .save_live_pending, .save_live_iterate and .save_live_complete_precopy functions. These functions handles pre-copy and stop-and-copy phase. In _SAVING|_RUNNING device state or pre-copy phase: - read pending_bytes. If pending_bytes > 0, go through below steps. - read data_offset - indicates kernel driver to write data to staging buffer. - read data_size - amount of data in bytes written by vendor driver in migration region. - read data_size bytes of data from data_offset in the migration region. - Write data packet to file stream as below: {VFIO_MIG_FLAG_DEV_DATA_STATE, data_size, actual data, VFIO_MIG_FLAG_END_OF_STATE } In _SAVING device state or stop-and-copy phase a. read config space of device and save to migration file stream. This doesn't need to be from vendor driver. Any other special config state from driver can be saved as data in following iteration. b. read pending_bytes. If pending_bytes > 0, go through below steps. c. read data_offset - indicates kernel driver to write data to staging buffer. d. read data_size - amount of data in bytes written by vendor driver in migration region. e. read data_size bytes of data from data_offset in the migration region. f. Write data packet as below: {VFIO_MIG_FLAG_DEV_DATA_STATE, data_size, actual data} g. iterate through steps b to f while (pending_bytes > 0) h. Write {VFIO_MIG_FLAG_END_OF_STATE} When data region is mapped, its user's responsibility to read data from data_offset of data_size before moving to next steps. .save_live_iterate runs outside the iothread lock in the migration case, which could race with asynchronous call to get dirty page list causing data corruption in mapped migration region. Mutex added here to serial migration buffer read operation. Signed-off-by: Kirti Wankhede Reviewed-by: Neo Jia --- hw/vfio/migration.c | 251 ++++++++++++++++++++++++++++++++++++++++++++++++++- hw/vfio/trace-events | 6 ++ 2 files changed, 256 insertions(+), 1 deletion(-) diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index 1910a913cde2..3b81c1d6f5b3 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -118,6 +118,137 @@ static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t set_flags, return 0; } +static void *find_data_region(VFIORegion *region, + uint64_t data_offset, + uint64_t data_size) +{ + void *ptr = NULL; + int i; + + for (i = 0; i < region->nr_mmaps; i++) { + if ((data_offset >= region->mmaps[i].offset) && + (data_offset < region->mmaps[i].offset + region->mmaps[i].size) && + (data_size <= region->mmaps[i].size)) { + ptr = region->mmaps[i].mmap + (data_offset - + region->mmaps[i].offset); + break; + } + } + return ptr; +} + +static int vfio_save_buffer(QEMUFile *f, VFIODevice *vbasedev) +{ + VFIOMigration *migration = vbasedev->migration; + VFIORegion *region = &migration->region; + uint64_t data_offset = 0, data_size = 0; + int ret; + + 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; + } + + ret = pread(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 get migration buffer data size %d", + vbasedev->name, ret); + return -EINVAL; + } + + if (data_size > 0) { + void *buf = NULL; + bool buffer_mmaped; + + if (region->mmaps) { + buf = find_data_region(region, data_offset, data_size); + } + + buffer_mmaped = (buf != NULL) ? true : false; + + if (!buffer_mmaped) { + buf = g_try_malloc0(data_size); + if (!buf) { + error_report("%s: Error allocating buffer ", __func__); + return -ENOMEM; + } + + ret = pread(vbasedev->fd, buf, data_size, + region->fd_offset + data_offset); + if (ret != data_size) { + error_report("%s: Failed to get migration data %d", + vbasedev->name, ret); + g_free(buf); + return -EINVAL; + } + } + + qemu_put_be64(f, data_size); + qemu_put_buffer(f, buf, data_size); + + if (!buffer_mmaped) { + g_free(buf); + } + } else { + qemu_put_be64(f, data_size); + } + + trace_vfio_save_buffer(vbasedev->name, data_offset, data_size, + migration->pending_bytes); + + ret = qemu_file_get_error(f); + if (ret) { + return ret; + } + + return data_size; +} + +static int vfio_update_pending(VFIODevice *vbasedev) +{ + VFIOMigration *migration = vbasedev->migration; + VFIORegion *region = &migration->region; + uint64_t pending_bytes = 0; + int ret; + + ret = pread(vbasedev->fd, &pending_bytes, sizeof(pending_bytes), + region->fd_offset + offsetof(struct vfio_device_migration_info, + pending_bytes)); + if ((ret < 0) || (ret != sizeof(pending_bytes))) { + error_report("%s: Failed to get pending bytes %d", + vbasedev->name, ret); + migration->pending_bytes = 0; + return (ret < 0) ? ret : -EINVAL; + } + + migration->pending_bytes = pending_bytes; + trace_vfio_update_pending(vbasedev->name, pending_bytes); + return 0; +} + +static int vfio_save_device_config_state(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_CONFIG_STATE); + + if (vbasedev->ops && vbasedev->ops->vfio_save_config) { + vbasedev->ops->vfio_save_config(vbasedev, f); + } + + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + + trace_vfio_save_device_config_state(vbasedev->name); + + return qemu_file_get_error(f); +} + /* ---------------------------------------------------------------------- */ static int vfio_save_setup(QEMUFile *f, void *opaque) @@ -134,7 +265,7 @@ static int vfio_save_setup(QEMUFile *f, void *opaque) qemu_mutex_unlock_iothread(); if (ret) { error_report("%s: Failed to mmap VFIO migration region %d: %s", - vbasedev->name, migration->region.index, + vbasedev->name, migration->region.nr, strerror(-ret)); return ret; } @@ -168,9 +299,124 @@ static void vfio_save_cleanup(void *opaque) trace_vfio_save_cleanup(vbasedev->name); } +static void vfio_save_pending(QEMUFile *f, void *opaque, + uint64_t threshold_size, + uint64_t *res_precopy_only, + uint64_t *res_compatible, + uint64_t *res_postcopy_only) +{ + VFIODevice *vbasedev = opaque; + VFIOMigration *migration = vbasedev->migration; + int ret; + + ret = vfio_update_pending(vbasedev); + if (ret) { + return; + } + + *res_precopy_only += migration->pending_bytes; + + trace_vfio_save_pending(vbasedev->name, *res_precopy_only, + *res_postcopy_only, *res_compatible); +} + +static int vfio_save_iterate(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + VFIOMigration *migration = vbasedev->migration; + int ret, data_size; + + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); + + qemu_mutex_lock(&migration->lock); + data_size = vfio_save_buffer(f, vbasedev); + qemu_mutex_unlock(&migration->lock); + + if (data_size < 0) { + error_report("%s: vfio_save_buffer failed %s", vbasedev->name, + strerror(errno)); + return data_size; + } + + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + + ret = qemu_file_get_error(f); + if (ret) { + return ret; + } + + trace_vfio_save_iterate(vbasedev->name, data_size); + if (data_size == 0) { + /* indicates data finished, goto complete phase */ + return 1; + } + + return 0; +} + +static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + VFIOMigration *migration = vbasedev->migration; + int ret; + + ret = vfio_migration_set_state(vbasedev, VFIO_DEVICE_STATE_SAVING, + VFIO_DEVICE_STATE_RUNNING); + if (ret) { + error_report("%s: Failed to set state STOP and SAVING", + vbasedev->name); + return ret; + } + + ret = vfio_save_device_config_state(f, opaque); + if (ret) { + return ret; + } + + ret = vfio_update_pending(vbasedev); + if (ret) { + return ret; + } + + while (migration->pending_bytes > 0) { + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); + ret = vfio_save_buffer(f, vbasedev); + if (ret < 0) { + error_report("%s: Failed to save buffer", vbasedev->name); + return ret; + } else if (ret == 0) { + break; + } + + ret = vfio_update_pending(vbasedev); + if (ret) { + return ret; + } + } + + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + + ret = qemu_file_get_error(f); + if (ret) { + return ret; + } + + ret = vfio_migration_set_state(vbasedev, 0, VFIO_DEVICE_STATE_SAVING); + if (ret) { + error_report("%s: Failed to set state STOPPED", vbasedev->name); + return ret; + } + + trace_vfio_save_complete_precopy(vbasedev->name); + 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, }; /* ---------------------------------------------------------------------- */ @@ -238,6 +484,8 @@ static int vfio_migration_init(VFIODevice *vbasedev, return ret; } + qemu_mutex_init(&vbasedev->migration->lock); + register_savevm_live(vbasedev->dev, "vfio", -1, 1, &savevm_vfio_handlers, vbasedev); vbasedev->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change, @@ -298,6 +546,7 @@ void vfio_migration_finalize(VFIODevice *vbasedev) error_free(vbasedev->migration_blocker); } + qemu_mutex_destroy(&vbasedev->migration->lock); vfio_migration_region_exit(vbasedev); if (vbasedev->migration) { diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events index 4bb43f18f315..bdf40ba368c7 100644 --- a/hw/vfio/trace-events +++ b/hw/vfio/trace-events @@ -151,3 +151,9 @@ vfio_vmstate_change(char *name, int running, const char *reason, uint32_t dev_st vfio_migration_state_notifier(char *name, int state) " (%s) state %d" vfio_save_setup(char *name) " (%s)" vfio_save_cleanup(char *name) " (%s)" +vfio_save_buffer(char *name, uint64_t data_offset, uint64_t data_size, uint64_t pending) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64" pending 0x%"PRIx64 +vfio_update_pending(char *name, uint64_t pending) " (%s) pending 0x%"PRIx64 +vfio_save_device_config_state(char *name) " (%s)" +vfio_save_pending(char *name, uint64_t precopy, uint64_t postcopy, uint64_t compatible) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64" compatible 0x%"PRIx64 +vfio_save_iterate(char *name, int data_size) " (%s) data_size %d" +vfio_save_complete_precopy(char *name) " (%s)"