From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648034497282927.357861019002; Wed, 23 Mar 2022 04:21:37 -0700 (PDT) Received: from localhost ([::1]:37606 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWz3Y-0006IH-23 for importer@patchew.org; Wed, 23 Mar 2022 07:21:36 -0400 Received: from eggs.gnu.org ([209.51.188.92]:36952) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzk-0000xz-Uo for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:41 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:55674) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzg-0001yK-3F for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:40 -0400 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-403-oN4q2bhaPSW-bELnyMPQHA-1; Wed, 23 Mar 2022 07:17:31 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C1F75185A7BA; Wed, 23 Mar 2022 11:17:30 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4B2EB41136E1; Wed, 23 Mar 2022 11:17:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034255; 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=WLnq4mun/H8h5jGXpNruvkOQAG3FzNTj3QZG2VFydpE=; b=PC9UC11GGqwIdx/nNWkEoQWZtoi/GDaXVcu7FkMSuWtvshjfYVIhjW1lEPeHAdEhZ25Ev9 ofiM2cn7/tSlngYW8EBq4kp/Bm0v2DcUg9gFb6YVL3CCMzxX9g8Xqj3P1zujDqMXolZnmY EfkF+T0QsSyxM9tql171umYhp/k5ikk= X-MC-Unique: oN4q2bhaPSW-bELnyMPQHA-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 1/8] blkio: add io_uring block driver using libblkio Date: Wed, 23 Mar 2022 11:17:20 +0000 Message-Id: <20220323111727.1100209-2-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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, T_SCC_BODY_TEXT_LINE=-0.01 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648034498567100001 Content-Type: text/plain; charset="utf-8" libblkio (https://gitlab.com/libblkio/libblkio/) is a library for high-performance disk I/O. It currently supports io_uring with additional drivers planned. One of the reasons for developing libblkio is that other applications besides QEMU can use it. This will be particularly useful for vhost-user-blk which applications may wish to use for connecting to qemu-storage-daemon. libblkio also gives us an opportunity to develop in Rust behind a C API that is easy to consume from QEMU. This commit adds an io_uring BlockDriver to QEMU using libblkio. For now I/O buffers are copied through bounce buffers if the libblkio driver requires it. Later commits add an optimization for pre-registering guest RAM to avoid bounce buffers. It will be easy to add other libblkio drivers since they will share the majority of code. Signed-off-by: Stefan Hajnoczi --- MAINTAINERS | 6 + meson_options.txt | 2 + qapi/block-core.json | 18 +- meson.build | 9 + block/blkio.c | 460 ++++++++++++++++++++++++++++++++++ tests/qtest/modules-test.c | 3 + block/meson.build | 1 + scripts/meson-buildoptions.sh | 3 + 8 files changed, 501 insertions(+), 1 deletion(-) create mode 100644 block/blkio.c diff --git a/MAINTAINERS b/MAINTAINERS index cc364afef7..0fb08dd4f7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3349,6 +3349,12 @@ L: qemu-block@nongnu.org S: Maintained F: block/vdi.c =20 +blkio +M: Stefan Hajnoczi +L: qemu-block@nongnu.org +S: Maintained +F: block/blkio.c + iSCSI M: Ronnie Sahlberg M: Paolo Bonzini diff --git a/meson_options.txt b/meson_options.txt index 52b11cead4..1e82e770e7 100644 --- a/meson_options.txt +++ b/meson_options.txt @@ -101,6 +101,8 @@ option('bzip2', type : 'feature', value : 'auto', description: 'bzip2 support for DMG images') option('cap_ng', type : 'feature', value : 'auto', description: 'cap_ng support') +option('blkio', type : 'feature', value : 'auto', + description: 'libblkio block device driver') option('bpf', type : 'feature', value : 'auto', description: 'eBPF support') option('cocoa', type : 'feature', value : 'auto', diff --git a/qapi/block-core.json b/qapi/block-core.json index e89f2dfb5b..d9bb283108 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2924,7 +2924,9 @@ 'file', 'snapshot-access', 'ftp', 'ftps', 'gluster', {'name': 'host_cdrom', 'if': 'HAVE_HOST_BLOCK_DEVICE' }, {'name': 'host_device', 'if': 'HAVE_HOST_BLOCK_DEVICE' }, - 'http', 'https', 'iscsi', + 'http', 'https', + { 'name': 'io_uring', 'if': 'CONFIG_BLKIO' }, + 'iscsi', 'luks', 'nbd', 'nfs', 'null-aio', 'null-co', 'nvme', 'parallel= s', 'preallocate', 'qcow', 'qcow2', 'qed', 'quorum', 'raw', 'rbd', { 'name': 'replication', 'if': 'CONFIG_REPLICATION' }, @@ -3656,6 +3658,18 @@ '*debug': 'int', '*logfile': 'str' } } =20 +## +# @BlockdevOptionsIoUring: +# +# Driver specific block device options for the io_uring backend. +# +# @filename: path to the image file +# +# Since: 6.3 +## +{ 'struct': 'BlockdevOptionsIoUring', + 'data': { 'filename': 'str' } } + ## # @IscsiTransport: # @@ -4254,6 +4268,8 @@ 'if': 'HAVE_HOST_BLOCK_DEVICE' }, 'http': 'BlockdevOptionsCurlHttp', 'https': 'BlockdevOptionsCurlHttps', + 'io_uring': { 'type': 'BlockdevOptionsIoUring', + 'if': 'CONFIG_BLKIO' }, 'iscsi': 'BlockdevOptionsIscsi', 'luks': 'BlockdevOptionsLUKS', 'nbd': 'BlockdevOptionsNbd', diff --git a/meson.build b/meson.build index aef724ad3c..d52f542b2e 100644 --- a/meson.build +++ b/meson.build @@ -636,6 +636,13 @@ if not get_option('virglrenderer').auto() or have_syst= em or have_vhost_user_gpu required: get_option('virglrenderer'), kwargs: static_kwargs) endif +blkio =3D not_found +if not get_option('blkio').auto() or have_block + blkio =3D dependency('blkio', + method: 'pkg-config', + required: get_option('blkio'), + kwargs: static_kwargs) +endif curl =3D not_found if not get_option('curl').auto() or have_block curl =3D dependency('libcurl', version: '>=3D7.29.0', @@ -1519,6 +1526,7 @@ config_host_data.set('CONFIG_LIBUDEV', libudev.found(= )) config_host_data.set('CONFIG_LZO', lzo.found()) config_host_data.set('CONFIG_MPATH', mpathpersist.found()) config_host_data.set('CONFIG_MPATH_NEW_API', mpathpersist_new_api) +config_host_data.set('CONFIG_BLKIO', blkio.found()) config_host_data.set('CONFIG_CURL', curl.found()) config_host_data.set('CONFIG_CURSES', curses.found()) config_host_data.set('CONFIG_GBM', gbm.found()) @@ -3672,6 +3680,7 @@ summary_info +=3D {'PAM': pam} summary_info +=3D {'iconv support': iconv} summary_info +=3D {'curses support': curses} summary_info +=3D {'virgl support': virgl} +summary_info +=3D {'blkio support': blkio} summary_info +=3D {'curl support': curl} summary_info +=3D {'Multipath support': mpathpersist} summary_info +=3D {'VNC support': vnc} diff --git a/block/blkio.c b/block/blkio.c new file mode 100644 index 0000000000..dd2308b967 --- /dev/null +++ b/block/blkio.c @@ -0,0 +1,460 @@ +#include "qemu/osdep.h" +#include +#include "block/block_int.h" +#include "qapi/error.h" +#include "qapi/qmp/qdict.h" +#include "qemu/module.h" + +typedef struct BlkAIOCB { + BlockAIOCB common; + struct blkio_mem_region mem_region; + QEMUIOVector qiov; + struct iovec bounce_iov; +} BlkioAIOCB; + +typedef struct { + /* Protects ->blkio and request submission on ->blkioq */ + QemuMutex lock; + + struct blkio *blkio; + struct blkioq *blkioq; /* this could be multi-queue in the future */ + int completion_fd; + + /* The value of the "mem-region-alignment" property */ + size_t mem_region_alignment; + + /* Can we skip adding/deleting blkio_mem_regions? */ + bool needs_mem_regions; + + /* + * blkio_completion_fd_poll() stashes the next completion for + * blkio_completion_fd_poll_ready(). + */ + struct blkio_completion pending_completion; +} BDRVBlkioState; + +static void blkio_aiocb_complete(BlkioAIOCB *acb, int ret) +{ + /* Copy bounce buffer back to qiov */ + if (acb->qiov.niov > 0) { + qemu_iovec_from_buf(&acb->qiov, 0, + acb->bounce_iov.iov_base, + acb->bounce_iov.iov_len); + qemu_iovec_destroy(&acb->qiov); + } + + acb->common.cb(acb->common.opaque, ret); + + if (acb->mem_region.len > 0) { + BDRVBlkioState *s =3D acb->common.bs->opaque; + + WITH_QEMU_LOCK_GUARD(&s->lock) { + blkio_free_mem_region(s->blkio, &acb->mem_region); + } + } + + qemu_aio_unref(&acb->common); +} + +/* + * Only the thread that calls aio_poll() invokes fd and poll handlers. + * Therefore locks are not necessary except when accessing s->blkio. + * + * No locking is performed around blkioq_get_completions() although other + * threads may submit I/O requests on s->blkioq. We're assuming there is no + * inteference between blkioq_get_completions() and other s->blkioq APIs. + */ + +static void blkio_completion_fd_read(void *opaque) +{ + BlockDriverState *bs =3D opaque; + BDRVBlkioState *s =3D bs->opaque; + struct blkio_completion completion; + uint64_t val; + ssize_t ret __attribute__((unused)); + + /* Reset completion fd status */ + ret =3D read(s->completion_fd, &val, sizeof(val)); + + /* + * Reading one completion at a time makes nested event loop re-entrancy + * simple. Change this loop to get multiple completions in one go if it + * becomes a performance bottleneck. + */ + while (blkioq_get_completions(s->blkioq, &completion, 1) =3D=3D 1) { + blkio_aiocb_complete(completion.user_data, completion.ret); + } +} + +static bool blkio_completion_fd_poll(void *opaque) +{ + BlockDriverState *bs =3D opaque; + BDRVBlkioState *s =3D bs->opaque; + + return blkioq_get_completions(s->blkioq, &s->pending_completion, 1) = =3D=3D 1; +} + +static void blkio_completion_fd_poll_ready(void *opaque) +{ + BlockDriverState *bs =3D opaque; + BDRVBlkioState *s =3D bs->opaque; + BlkioAIOCB *acb =3D s->pending_completion.user_data; + + blkio_aiocb_complete(acb, s->pending_completion.ret); + + /* Process any remaining completions */ + blkio_completion_fd_read(opaque); +} + +static void blkio_attach_aio_context(BlockDriverState *bs, + AioContext *new_context) +{ + BDRVBlkioState *s =3D bs->opaque; + + aio_set_fd_handler(new_context, + s->completion_fd, + false, + blkio_completion_fd_read, + NULL, + blkio_completion_fd_poll, + blkio_completion_fd_poll_ready, + bs); +} + +static void blkio_detach_aio_context(BlockDriverState *bs) +{ + BDRVBlkioState *s =3D bs->opaque; + + aio_set_fd_handler(bdrv_get_aio_context(bs), + s->completion_fd, + false, NULL, NULL, NULL, NULL, NULL); +} + +static const AIOCBInfo blkio_aiocb_info =3D { + .aiocb_size =3D sizeof(BlkioAIOCB), +}; + +/* Create a BlkioAIOCB */ +static BlkioAIOCB *blkio_aiocb_get(BlockDriverState *bs, + BlockCompletionFunc *cb, + void *opaque) +{ + BlkioAIOCB *acb =3D qemu_aio_get(&blkio_aiocb_info, bs, cb, opaque); + + /* A few fields need to be initialized, leave the rest... */ + acb->qiov.niov =3D 0; + acb->mem_region.len =3D 0; + return acb; +} + +/* s->lock must be held */ +static int blkio_aiocb_init_mem_region_locked(BlkioAIOCB *acb, size_t len) +{ + BDRVBlkioState *s =3D acb->common.bs->opaque; + size_t mem_region_len =3D QEMU_ALIGN_UP(len, s->mem_region_alignment); + int ret; + + ret =3D blkio_alloc_mem_region(s->blkio, &acb->mem_region, mem_region_= len, + 0, NULL); + if (ret < 0) { + return ret; + } + + acb->bounce_iov.iov_base =3D acb->mem_region.addr; + acb->bounce_iov.iov_len =3D len; + return 0; +} + +static BlockAIOCB *blkio_aio_preadv(BlockDriverState *bs, int64_t offset, + int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags, + BlockCompletionFunc *cb, void *opaque) +{ + BDRVBlkioState *s =3D bs->opaque; + struct iovec *iov =3D qiov->iov; + int iovcnt =3D qiov->niov; + BlkioAIOCB *acb; + int ret; + + QEMU_LOCK_GUARD(&s->lock); + + acb =3D blkio_aiocb_get(bs, cb, opaque); + + if (s->needs_mem_regions) { + if (blkio_aiocb_init_mem_region_locked(acb, bytes) < 0) { + qemu_aio_unref(&acb->common); + return NULL; + } + + /* Copy qiov because we'll call qemu_iovec_from_buf() on completio= n */ + qemu_iovec_init_slice(&acb->qiov, qiov, 0, qiov->size); + + iov =3D &acb->bounce_iov; + iovcnt =3D 1; + } + + ret =3D blkioq_readv(s->blkioq, offset, iov, iovcnt, acb, 0); + if (ret < 0) { + if (s->needs_mem_regions) { + blkio_free_mem_region(s->blkio, &acb->mem_region); + qemu_iovec_destroy(&acb->qiov); + } + qemu_aio_unref(&acb->common); + return NULL; + } + + if (qatomic_read(&bs->io_plugged) =3D=3D 0) { + blkioq_submit_and_wait(s->blkioq, 0, NULL, NULL); + } + + return &acb->common; +} + +static BlockAIOCB *blkio_aio_pwritev(BlockDriverState *bs, int64_t offset, + int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags, + BlockCompletionFunc *cb, void *opaque) +{ + uint32_t blkio_flags =3D (flags & BDRV_REQ_FUA) ? BLKIO_REQ_FUA : 0; + BDRVBlkioState *s =3D bs->opaque; + struct iovec *iov =3D qiov->iov; + int iovcnt =3D qiov->niov; + BlkioAIOCB *acb; + int ret; + + QEMU_LOCK_GUARD(&s->lock); + + acb =3D blkio_aiocb_get(bs, cb, opaque); + + if (s->needs_mem_regions) { + if (blkio_aiocb_init_mem_region_locked(acb, bytes) < 0) { + qemu_aio_unref(&acb->common); + return NULL; + } + + qemu_iovec_to_buf(qiov, 0, acb->bounce_iov.iov_base, bytes); + + iov =3D &acb->bounce_iov; + iovcnt =3D 1; + } + + ret =3D blkioq_writev(s->blkioq, offset, iov, iovcnt, acb, blkio_flags= ); + if (ret < 0) { + if (s->needs_mem_regions) { + blkio_free_mem_region(s->blkio, &acb->mem_region); + } + qemu_aio_unref(&acb->common); + return NULL; + } + + if (qatomic_read(&bs->io_plugged) =3D=3D 0) { + blkioq_submit_and_wait(s->blkioq, 0, NULL, NULL); + } + + return &acb->common; +} + +static BlockAIOCB *blkio_aio_flush(BlockDriverState *bs, + BlockCompletionFunc *cb, + void *opaque) +{ + BDRVBlkioState *s =3D bs->opaque; + BlkioAIOCB *acb; + int ret; + + QEMU_LOCK_GUARD(&s->lock); + + acb =3D blkio_aiocb_get(bs, cb, opaque); + + ret =3D blkioq_flush(s->blkioq, acb, 0); + if (ret < 0) { + qemu_aio_unref(&acb->common); + return NULL; + } + + if (qatomic_read(&bs->io_plugged) =3D=3D 0) { + blkioq_submit_and_wait(s->blkioq, 0, NULL, NULL); + } + + return &acb->common; +} + +static void blkio_io_unplug(BlockDriverState *bs) +{ + BDRVBlkioState *s =3D bs->opaque; + + WITH_QEMU_LOCK_GUARD(&s->lock) { + blkioq_submit_and_wait(s->blkioq, 0, NULL, NULL); + } +} + +static void blkio_parse_filename_io_uring(const char *filename, QDict *opt= ions, + Error **errp) +{ + bdrv_parse_filename_strip_prefix(filename, "io_uring:", options); +} + +static int blkio_file_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) +{ + const char *filename =3D qdict_get_try_str(options, "filename"); + const char *blkio_driver =3D bs->drv->protocol_name; + BDRVBlkioState *s =3D bs->opaque; + char *errmsg; + int ret; + + ret =3D blkio_create(blkio_driver, &s->blkio, &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, "blkio_create failed: %s", errmsg); + free(errmsg); + return ret; + } + + ret =3D blkio_set_str(s->blkio, "path", filename, &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, "failed to set path: %s", errmsg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + + if (flags & BDRV_O_NOCACHE) { + ret =3D blkio_set_bool(s->blkio, "direct", true, &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, "failed to set direct: %s", errms= g); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + } + + if (!(flags & BDRV_O_RDWR)) { + ret =3D blkio_set_bool(s->blkio, "readonly", true, &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, "failed to set readonly: %s", err= msg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + } + + ret =3D blkio_connect(s->blkio, &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, "blkio_connect failed: %s", errmsg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + + ret =3D blkio_get_bool(s->blkio, + "needs-mem-regions", + &s->needs_mem_regions, + &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, + "failed to get needs-mem-regions: %s", errmsg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + + ret =3D blkio_get_uint64(s->blkio, + "mem-region-alignment", + &s->mem_region_alignment, + &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, + "failed to get mem-region-alignment: %s", errmsg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + + ret =3D blkio_start(s->blkio, &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, "blkio_start failed: %s", errmsg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + + bs->supported_write_flags =3D BDRV_REQ_FUA; + + qemu_mutex_init(&s->lock); + s->blkioq =3D blkio_get_queue(s->blkio, 0); + s->completion_fd =3D blkioq_get_completion_fd(s->blkioq); + + blkio_attach_aio_context(bs, bdrv_get_aio_context(bs)); + + qdict_del(options, "filename"); + return 0; +} + +static void blkio_close(BlockDriverState *bs) +{ + BDRVBlkioState *s =3D bs->opaque; + + qemu_mutex_destroy(&s->lock); + blkio_destroy(&s->blkio); +} + +static int64_t blkio_getlength(BlockDriverState *bs) +{ + BDRVBlkioState *s =3D bs->opaque; + char *errmsg; + uint64_t capacity; + int ret; + + WITH_QEMU_LOCK_GUARD(&s->lock) { + ret =3D blkio_get_uint64(s->blkio, "capacity", &capacity, &errmsg); + } + if (ret < 0) { + free(errmsg); + return -ret; + } + + return capacity; +} + +static int blkio_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) +{ + return 0; +} + +static BlockDriver bdrv_io_uring =3D { + .format_name =3D "io_uring", + .protocol_name =3D "io_uring", + .instance_size =3D sizeof(BDRVBlkioState), + .bdrv_needs_filename =3D true, + .bdrv_parse_filename =3D blkio_parse_filename_io_uring, + .bdrv_file_open =3D blkio_file_open, + .bdrv_close =3D blkio_close, + .bdrv_getlength =3D blkio_getlength, + .has_variable_length =3D true, + .bdrv_get_info =3D blkio_get_info, + .bdrv_attach_aio_context =3D blkio_attach_aio_context, + .bdrv_detach_aio_context =3D blkio_detach_aio_context, + .bdrv_aio_preadv =3D blkio_aio_preadv, + .bdrv_aio_pwritev =3D blkio_aio_pwritev, + .bdrv_aio_flush =3D blkio_aio_flush, + .bdrv_io_unplug =3D blkio_io_unplug, + + /* + * TODO + * Missing libblkio APIs: + * - bdrv_refresh_limits + * - write zeroes + * - discard + * - block_status + * - co_invalidate_cache + * + * Out of scope? + * - create + * - truncate + */ +}; + +static void bdrv_blkio_init(void) +{ + bdrv_register(&bdrv_io_uring); +} + +block_init(bdrv_blkio_init); diff --git a/tests/qtest/modules-test.c b/tests/qtest/modules-test.c index c238b3f422..2e0f73fdc6 100644 --- a/tests/qtest/modules-test.c +++ b/tests/qtest/modules-test.c @@ -16,6 +16,9 @@ static void test_modules_load(const void *data) int main(int argc, char *argv[]) { const char *modules[] =3D { +#ifdef CONFIG_BLKIO + "block-", "blkio", +#endif #ifdef CONFIG_CURL "block-", "curl", #endif diff --git a/block/meson.build b/block/meson.build index 0b2a60c99b..787667384a 100644 --- a/block/meson.build +++ b/block/meson.build @@ -92,6 +92,7 @@ block_modules =3D {} =20 modsrc =3D [] foreach m : [ + [blkio, 'blkio', files('blkio.c')], [curl, 'curl', files('curl.c')], [glusterfs, 'gluster', files('gluster.c')], [libiscsi, 'iscsi', [files('iscsi.c'), libm]], diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh index 1e26f4571e..845a29b9b7 100644 --- a/scripts/meson-buildoptions.sh +++ b/scripts/meson-buildoptions.sh @@ -40,6 +40,7 @@ meson_options_help() { printf "%s\n" ' auth-pam PAM access control' printf "%s\n" ' avx2 AVX2 optimizations' printf "%s\n" ' avx512f AVX512F optimizations' + printf "%s\n" ' blkio libblkio block device driver' printf "%s\n" ' bochs bochs image format support' printf "%s\n" ' bpf eBPF support' printf "%s\n" ' brlapi brlapi character device driver' @@ -146,6 +147,8 @@ _meson_option_parse() { --disable-avx2) printf "%s" -Davx2=3Ddisabled ;; --enable-avx512f) printf "%s" -Davx512f=3Denabled ;; --disable-avx512f) printf "%s" -Davx512f=3Ddisabled ;; + --enable-blkio) printf "%s" -Dblkio=3Denabled ;; + --disable-blkio) printf "%s" -Dblkio=3Ddisabled ;; --enable-block-drv-whitelist-in-tools) printf "%s" -Dblock_drv_whiteli= st_in_tools=3Dtrue ;; --disable-block-drv-whitelist-in-tools) printf "%s" -Dblock_drv_whitel= ist_in_tools=3Dfalse ;; --enable-bochs) printf "%s" -Dbochs=3Denabled ;; --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648034742586687.6644079638514; Wed, 23 Mar 2022 04:25:42 -0700 (PDT) Received: from localhost ([::1]:48096 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWz7V-0004vo-Gv for importer@patchew.org; Wed, 23 Mar 2022 07:25:41 -0400 Received: from eggs.gnu.org ([209.51.188.92]:36914) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzk-0000w5-7X for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:40 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:39813) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzh-0001yR-A9 for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:39 -0400 Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [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-136-zBzeHJq-PCuhXncZnondcw-1; Wed, 23 Mar 2022 07:17:32 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 536722999B38; Wed, 23 Mar 2022 11:17:32 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id DF53940E80E5; Wed, 23 Mar 2022 11:17:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034256; 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=vubr7SGLSeCuMS54pPuWQ+C77Syxyx2gW0fdGja/Nsg=; b=cst69tiOS664ztgUaAueAbL7oGaiiMfmcyiIauweaHIIGkMv0Pl1ejirMhuvyPffjjiLFD uZx5aHtdNkq8gTY6k89VO4P9yRFjLhcNPUDKzDNSZpQbrO6/J/0LFgnhJydllv2zZ4DmUv eEHWw0gPN2P19CK+kEdn/CbBMdmT4QQ= X-MC-Unique: zBzeHJq-PCuhXncZnondcw-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 2/8] numa: call ->ram_block_removed() in ram_block_notifer_remove() Date: Wed, 23 Mar 2022 11:17:21 +0000 Message-Id: <20220323111727.1100209-3-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.11.54.2 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , David Hildenbrand , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648034743909100001 Content-Type: text/plain; charset="utf-8"; x-default="true" When a RAMBlockNotifier is added, ->ram_block_added() is called with all existing RAMBlocks. There is no equivalent ->ram_block_removed() call when a RAMBlockNotifier is removed. The util/vfio-helpers.c code (the sole user of RAMBlockNotifier) is fine with this asymmetry because it does not rely on RAMBlockNotifier for cleanup. It walks its internal list of DMA mappings and unmaps them by itself. Future users of RAMBlockNotifier may not have an internal data structure that records added RAMBlocks so they will need ->ram_block_removed() callbacks. This patch makes ram_block_notifier_remove() symmetric with respect to callbacks. Now util/vfio-helpers.c needs to unmap remaining DMA mappings after ram_block_notifier_remove() has been called. This is necessary since users like block/nvme.c may create additional DMA mappings that do not originate from the RAMBlockNotifier. Cc: David Hildenbrand Signed-off-by: Stefan Hajnoczi Reviewed-by: David Hildenbrand --- hw/core/numa.c | 17 +++++++++++++++++ util/vfio-helpers.c | 5 ++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/hw/core/numa.c b/hw/core/numa.c index 1aa05dcf42..6bf9694d20 100644 --- a/hw/core/numa.c +++ b/hw/core/numa.c @@ -822,6 +822,19 @@ static int ram_block_notify_add_single(RAMBlock *rb, v= oid *opaque) return 0; } =20 +static int ram_block_notify_remove_single(RAMBlock *rb, void *opaque) +{ + const ram_addr_t max_size =3D qemu_ram_get_max_length(rb); + const ram_addr_t size =3D qemu_ram_get_used_length(rb); + void *host =3D qemu_ram_get_host_addr(rb); + RAMBlockNotifier *notifier =3D opaque; + + if (host) { + notifier->ram_block_removed(notifier, host, size, max_size); + } + return 0; +} + void ram_block_notifier_add(RAMBlockNotifier *n) { QLIST_INSERT_HEAD(&ram_list.ramblock_notifiers, n, next); @@ -835,6 +848,10 @@ void ram_block_notifier_add(RAMBlockNotifier *n) void ram_block_notifier_remove(RAMBlockNotifier *n) { QLIST_REMOVE(n, next); + + if (n->ram_block_removed) { + qemu_ram_foreach_block(ram_block_notify_remove_single, n); + } } =20 void ram_block_notify_add(void *host, size_t size, size_t max_size) diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c index b037d5faa5..dc90496592 100644 --- a/util/vfio-helpers.c +++ b/util/vfio-helpers.c @@ -847,10 +847,13 @@ void qemu_vfio_close(QEMUVFIOState *s) if (!s) { return; } + + ram_block_notifier_remove(&s->ram_notifier); + for (i =3D 0; i < s->nr_mappings; ++i) { qemu_vfio_undo_mapping(s, &s->mappings[i], NULL); } - ram_block_notifier_remove(&s->ram_notifier); + g_free(s->usable_iova_ranges); s->nb_iova_ranges =3D 0; qemu_vfio_reset(s); --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648034590813853.6992313605801; Wed, 23 Mar 2022 04:23:10 -0700 (PDT) Received: from localhost ([::1]:42028 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWz53-0000pS-Ig for importer@patchew.org; Wed, 23 Mar 2022 07:23:09 -0400 Received: from eggs.gnu.org ([209.51.188.92]:36950) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzk-0000xm-UO for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:41 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:49396) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzi-0001z3-FA for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:40 -0400 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-661-R2df_69oOT2X0T-Og4rU-Q-1; Wed, 23 Mar 2022 07:17:34 -0400 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 618A3899EC2; Wed, 23 Mar 2022 11:17:34 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id EB36656D191; Wed, 23 Mar 2022 11:17:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034257; 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=GuhMYgQSjvwA+WE+0m5ZgSh1iQlddJXFUZbFhus+bSY=; b=d84y8KNHdhce4XN2zxvddxIC5ARPxRnwVsfna1CqoZUW9n5ap8OmCyhL2VYSsmxJ/wEyGX r6+/NI0t2oyx6CkIzQbf6Fo3BF/PbC+xzZqwTHW8jnaiQ5U3S0c00luWnslGWZ54Smzq3f FexbGlwYB03g9q0efcnT1Xp53WoZ/kQ= X-MC-Unique: R2df_69oOT2X0T-Og4rU-Q-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 3/8] block: pass size to bdrv_unregister_buf() Date: Wed, 23 Mar 2022 11:17:22 +0000 Message-Id: <20220323111727.1100209-4-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648034593238100001 Content-Type: text/plain; charset="utf-8" The only implementor of bdrv_register_buf() is block/nvme.c, where the size is not needed when unregistering a buffer. This is because util/vfio-helpers.c can look up mappings by address. Future block drivers that implement bdrv_register_buf() may not be able to do their job given only the buffer address. Add a size argument to bdrv_unregister_buf(). Also document the assumptions about bdrv_register_buf()/bdrv_unregister_buf() calls. The same values that were given to bdrv_register_buf() must be given to bdrv_unregister_buf(). gcc 11.2.1 emits a spurious warning that img_bench()'s buf_size local variable might be uninitialized, so it's necessary to silence the compiler. Signed-off-by: Stefan Hajnoczi --- include/block/block-global-state.h | 5 ++++- include/block/block_int-common.h | 2 +- include/sysemu/block-backend-global-state.h | 2 +- block/block-backend.c | 4 ++-- block/io.c | 6 +++--- block/nvme.c | 2 +- qemu-img.c | 4 ++-- 7 files changed, 14 insertions(+), 11 deletions(-) diff --git a/include/block/block-global-state.h b/include/block/block-globa= l-state.h index 25bb69bbef..2295a7c767 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -244,9 +244,12 @@ void bdrv_del_child(BlockDriverState *parent, BdrvChil= d *child, Error **errp); * Register/unregister a buffer for I/O. For example, VFIO drivers are * interested to know the memory areas that would later be used for I/O, so * that they can prepare IOMMU mapping etc., to get better performance. + * + * Buffers must not overlap and they must be unregistered with the same values that they were registered with. */ void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); -void bdrv_unregister_buf(BlockDriverState *bs, void *host); +void bdrv_unregister_buf(BlockDriverState *bs, void *host, size_t size); =20 void bdrv_cancel_in_flight(BlockDriverState *bs); =20 diff --git a/include/block/block_int-common.h b/include/block/block_int-com= mon.h index 8947abab76..b7a7cbd3a5 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -435,7 +435,7 @@ struct BlockDriver { * DMA mapping for hot buffers. */ void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t siz= e); - void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host); + void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host, size_t s= ize); =20 /* * This field is modified only under the BQL, and is part of diff --git a/include/sysemu/block-backend-global-state.h b/include/sysemu/b= lock-backend-global-state.h index 2e93a74679..989ec0364b 100644 --- a/include/sysemu/block-backend-global-state.h +++ b/include/sysemu/block-backend-global-state.h @@ -107,7 +107,7 @@ void blk_io_limits_update_group(BlockBackend *blk, cons= t char *group); void blk_set_force_allow_inactivate(BlockBackend *blk); =20 void blk_register_buf(BlockBackend *blk, void *host, size_t size); -void blk_unregister_buf(BlockBackend *blk, void *host); +void blk_unregister_buf(BlockBackend *blk, void *host, size_t size); =20 const BdrvChild *blk_root(BlockBackend *blk); =20 diff --git a/block/block-backend.c b/block/block-backend.c index e0e1aff4b1..8af00d8a36 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -2591,10 +2591,10 @@ void blk_register_buf(BlockBackend *blk, void *host= , size_t size) bdrv_register_buf(blk_bs(blk), host, size); } =20 -void blk_unregister_buf(BlockBackend *blk, void *host) +void blk_unregister_buf(BlockBackend *blk, void *host, size_t size) { GLOBAL_STATE_CODE(); - bdrv_unregister_buf(blk_bs(blk), host); + bdrv_unregister_buf(blk_bs(blk), host, size); } =20 int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in, diff --git a/block/io.c b/block/io.c index 3280144a17..a8a7920e29 100644 --- a/block/io.c +++ b/block/io.c @@ -3365,16 +3365,16 @@ void bdrv_register_buf(BlockDriverState *bs, void *= host, size_t size) } } =20 -void bdrv_unregister_buf(BlockDriverState *bs, void *host) +void bdrv_unregister_buf(BlockDriverState *bs, void *host, size_t size) { BdrvChild *child; =20 GLOBAL_STATE_CODE(); if (bs->drv && bs->drv->bdrv_unregister_buf) { - bs->drv->bdrv_unregister_buf(bs, host); + bs->drv->bdrv_unregister_buf(bs, host, size); } QLIST_FOREACH(child, &bs->children, next) { - bdrv_unregister_buf(child->bs, host); + bdrv_unregister_buf(child->bs, host, size); } } =20 diff --git a/block/nvme.c b/block/nvme.c index 552029931d..88485e77f1 100644 --- a/block/nvme.c +++ b/block/nvme.c @@ -1592,7 +1592,7 @@ static void nvme_register_buf(BlockDriverState *bs, v= oid *host, size_t size) } } =20 -static void nvme_unregister_buf(BlockDriverState *bs, void *host) +static void nvme_unregister_buf(BlockDriverState *bs, void *host, size_t s= ize) { BDRVNVMeState *s =3D bs->opaque; =20 diff --git a/qemu-img.c b/qemu-img.c index 1caddfb23a..493fad758a 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -4363,7 +4363,7 @@ static int img_bench(int argc, char **argv) struct timeval t1, t2; int i; bool force_share =3D false; - size_t buf_size; + size_t buf_size =3D 0; =20 for (;;) { static const struct option long_options[] =3D { @@ -4585,7 +4585,7 @@ static int img_bench(int argc, char **argv) =20 out: if (data.buf) { - blk_unregister_buf(blk, data.buf); + blk_unregister_buf(blk, data.buf, buf_size); } qemu_vfree(data.buf); blk_unref(blk); --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648034676427589.337481884055; 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Wed, 23 Mar 2022 11:17:36 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id ACC5DC27D8C; Wed, 23 Mar 2022 11:17:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034259; 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=qtIiIG5cYjGFrp5Olf62TgllKgB7t+S2bdDeFCbd31o=; b=DgvtiPJ1RZLILcQ1JeBMuHey6Uyu2+LXxQYug6eFm0AyOCATImOHLU61i0VM3wCSYBJrog ygHrkJwTeh+U5FHHRhYtVJA9U5Z24UFXj4qTMz9kfaMrrfTK52rSyE1TyYZyaQEfateLF/ EXVcrYGbdCCSjz9A7On3dCdLev6tDAw= X-MC-Unique: tnuIouCcMLmdxHAATYdOYA-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 4/8] block: add BDRV_REQ_REGISTERED_BUF request flag Date: Wed, 23 Mar 2022 11:17:23 +0000 Message-Id: <20220323111727.1100209-5-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.8 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648034677370100001 Content-Type: text/plain; charset="utf-8" Block drivers may optimize I/O requests accessing buffers previously registered with bdrv_register_buf(). Checking whether all elements of a request's QEMUIOVector are within previously registered buffers is expensive, so we need a hint from the user to avoid costly checks. Add a BDRV_REQ_REGISTERED_BUF request flag to indicate that all QEMUIOVector elements in an I/O request are known to be within previously registered buffers. bdrv_aligned_preadv() is strict in validating supported read flags and its assertions fail when it sees BDRV_REQ_REGISTERED_BUF. There is no harm in passing BDRV_REQ_REGISTERED_BUF to block drivers that do not support it, so update the assertions to ignore BDRV_REQ_REGISTERED_BUF. Care must be taken to clear the flag when the block layer or filter drivers replace QEMUIOVector elements with bounce buffers since these have not been registered with bdrv_register_buf(). A lot of the changes in this commit deal with clearing the flag in those cases. Ensuring that the flag is cleared properly is somewhat invasive to implement across the block layer and it's hard to spot when future code changes accidentally break it. Another option might be to add a flag to QEMUIOVector itself and clear it in qemu_iovec_*() functions that modify elements. That is more robust but somewhat of a layering violation, so I haven't attempted that. Signed-off-by: Stefan Hajnoczi --- include/block/block-common.h | 9 +++++++++ block/blkverify.c | 4 ++-- block/crypto.c | 2 ++ block/io.c | 30 +++++++++++++++++++++++------- block/mirror.c | 2 ++ block/raw-format.c | 2 ++ 6 files changed, 40 insertions(+), 9 deletions(-) diff --git a/include/block/block-common.h b/include/block/block-common.h index fdb7306e78..061606e867 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -80,6 +80,15 @@ typedef enum { */ BDRV_REQ_MAY_UNMAP =3D 0x4, =20 + /* + * An optimization hint when all QEMUIOVector elements are within + * previously registered bdrv_register_buf() memory ranges. + * + * Code that replaces the user's QEMUIOVector elements with bounce buf= fers + * must take care to clear this flag. + */ + BDRV_REQ_REGISTERED_BUF =3D 0x8, + BDRV_REQ_FUA =3D 0x10, BDRV_REQ_WRITE_COMPRESSED =3D 0x20, =20 diff --git a/block/blkverify.c b/block/blkverify.c index e4a37af3b2..d624f4fd05 100644 --- a/block/blkverify.c +++ b/block/blkverify.c @@ -235,8 +235,8 @@ blkverify_co_preadv(BlockDriverState *bs, int64_t offse= t, int64_t bytes, qemu_iovec_init(&raw_qiov, qiov->niov); qemu_iovec_clone(&raw_qiov, qiov, buf); =20 - ret =3D blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, flag= s, - false); + ret =3D blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, + flags & ~BDRV_REQ_REGISTERED_BUF, false); =20 cmp_offset =3D qemu_iovec_compare(qiov, &raw_qiov); if (cmp_offset !=3D -1) { diff --git a/block/crypto.c b/block/crypto.c index 1ba82984ef..c900355adb 100644 --- a/block/crypto.c +++ b/block/crypto.c @@ -473,6 +473,8 @@ block_crypto_co_pwritev(BlockDriverState *bs, int64_t o= ffset, int64_t bytes, uint64_t sector_size =3D qcrypto_block_get_sector_size(crypto->block); uint64_t payload_offset =3D qcrypto_block_get_payload_offset(crypto->b= lock); =20 + flags &=3D ~BDRV_REQ_REGISTERED_BUF; + assert(!(flags & ~BDRV_REQ_FUA)); assert(payload_offset < INT64_MAX); assert(QEMU_IS_ALIGNED(offset, sector_size)); diff --git a/block/io.c b/block/io.c index a8a7920e29..139e36c2e1 100644 --- a/block/io.c +++ b/block/io.c @@ -1556,11 +1556,14 @@ static int coroutine_fn bdrv_aligned_preadv(BdrvChi= ld *child, max_transfer =3D QEMU_ALIGN_DOWN(MIN_NON_ZERO(bs->bl.max_transfer, INT= _MAX), align); =20 - /* TODO: We would need a per-BDS .supported_read_flags and + /* + * TODO: We would need a per-BDS .supported_read_flags and * potential fallback support, if we ever implement any read flags * to pass through to drivers. For now, there aren't any - * passthrough flags. */ - assert(!(flags & ~(BDRV_REQ_COPY_ON_READ | BDRV_REQ_PREFETCH))); + * passthrough flags except the BDRV_REQ_REGISTERED_BUF optimization h= int. + */ + assert(!(flags & ~(BDRV_REQ_COPY_ON_READ | BDRV_REQ_PREFETCH | + BDRV_REQ_REGISTERED_BUF))); =20 /* Handle Copy on Read and associated serialisation */ if (flags & BDRV_REQ_COPY_ON_READ) { @@ -1601,7 +1604,7 @@ static int coroutine_fn bdrv_aligned_preadv(BdrvChild= *child, goto out; } =20 - assert(!(flags & ~bs->supported_read_flags)); + assert(!(flags & ~(bs->supported_read_flags | BDRV_REQ_REGISTERED_BUF)= )); =20 max_bytes =3D ROUND_UP(MAX(0, total_bytes - offset), align); if (bytes <=3D max_bytes && bytes <=3D max_transfer) { @@ -1790,7 +1793,8 @@ static void bdrv_padding_destroy(BdrvRequestPadding *= pad) static int bdrv_pad_request(BlockDriverState *bs, QEMUIOVector **qiov, size_t *qiov_offset, int64_t *offset, int64_t *bytes, - BdrvRequestPadding *pad, bool *padded) + BdrvRequestPadding *pad, bool *padded, + BdrvRequestFlags *flags) { int ret; =20 @@ -1818,6 +1822,10 @@ static int bdrv_pad_request(BlockDriverState *bs, if (padded) { *padded =3D true; } + if (flags) { + /* Can't use optimization hint with bounce buffer */ + *flags &=3D ~BDRV_REQ_REGISTERED_BUF; + } =20 return 0; } @@ -1872,7 +1880,7 @@ int coroutine_fn bdrv_co_preadv_part(BdrvChild *child, } =20 ret =3D bdrv_pad_request(bs, &qiov, &qiov_offset, &offset, &bytes, &pa= d, - NULL); + NULL, &flags); if (ret < 0) { goto fail; } @@ -1917,6 +1925,11 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(Blo= ckDriverState *bs, return -ENOTSUP; } =20 + /* By definition there is no user buffer so this flag doesn't make sen= se */ + if (flags & BDRV_REQ_REGISTERED_BUF) { + return -EINVAL; + } + /* Invalidate the cached block-status data range if this write overlap= s */ bdrv_bsc_invalidate_range(bs, offset, bytes); =20 @@ -2202,6 +2215,9 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvC= hild *child, bool padding; BdrvRequestPadding pad; =20 + /* This flag doesn't make sense for padding or zero writes */ + flags &=3D ~BDRV_REQ_REGISTERED_BUF; + padding =3D bdrv_init_padding(bs, offset, bytes, &pad); if (padding) { assert(!(flags & BDRV_REQ_NO_WAIT)); @@ -2319,7 +2335,7 @@ int coroutine_fn bdrv_co_pwritev_part(BdrvChild *chil= d, * alignment only if there is no ZERO flag. */ ret =3D bdrv_pad_request(bs, &qiov, &qiov_offset, &offset, &bytes,= &pad, - &padded); + &padded, &flags); if (ret < 0) { return ret; } diff --git a/block/mirror.c b/block/mirror.c index d8ecb9efa2..3a0773622d 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -1477,6 +1477,8 @@ static int coroutine_fn bdrv_mirror_top_pwritev(Block= DriverState *bs, qemu_iovec_init(&bounce_qiov, 1); qemu_iovec_add(&bounce_qiov, bounce_buf, bytes); qiov =3D &bounce_qiov; + + flags &=3D ~BDRV_REQ_REGISTERED_BUF; } =20 ret =3D bdrv_mirror_top_do_write(bs, MIRROR_METHOD_COPY, offset, bytes= , qiov, diff --git a/block/raw-format.c b/block/raw-format.c index 69fd650eaf..9bae3dd7f2 100644 --- a/block/raw-format.c +++ b/block/raw-format.c @@ -258,6 +258,8 @@ static int coroutine_fn raw_co_pwritev(BlockDriverState= *bs, int64_t offset, qemu_iovec_add(&local_qiov, buf, 512); qemu_iovec_concat(&local_qiov, qiov, 512, qiov->size - 512); qiov =3D &local_qiov; + + flags &=3D ~BDRV_REQ_REGISTERED_BUF; } =20 ret =3D raw_adjust_offset(bs, &offset, bytes, true); --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648034946261196.15504968833136; Wed, 23 Mar 2022 04:29:06 -0700 (PDT) Received: from localhost ([::1]:32976 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWzAn-0005Uw-9P for importer@patchew.org; Wed, 23 Mar 2022 07:29:05 -0400 Received: from eggs.gnu.org ([209.51.188.92]:37002) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzn-00010E-Dl for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:43 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:47128) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzl-000200-OS for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:43 -0400 Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [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-159-AUMWp7DxNw-3tfaCX7Oefw-1; Wed, 23 Mar 2022 07:17:38 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A3D102999B3B; Wed, 23 Mar 2022 11:17:37 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3F413141DC5F; Wed, 23 Mar 2022 11:17:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034261; 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=rWJ7+zKBlrt1uM/zJGD/voLiw0zPtkuenWcN6xj9U9I=; b=JDRQUzOk7I4804CarkFU6SU1hm1srsJgmatKnGIcmJ8mHIHGc/Whd0kALpTk4gVEDi5BWd ihLX3ohWcuzJ+oTj0pZHCQnddYafDr2JXAsW1gO0LVlPselOQi7IV/RUYxIZmRlo43crrB 6zbgBVx59MbJuei1XnwApDXewZZaDI8= X-MC-Unique: AUMWp7DxNw-3tfaCX7Oefw-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 5/8] block: add BlockRAMRegistrar Date: Wed, 23 Mar 2022 11:17:24 +0000 Message-Id: <20220323111727.1100209-6-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648034947864100001 Content-Type: text/plain; charset="utf-8"; x-default="true" Emulated devices and other BlockBackend users wishing to take advantage of blk_register_buf() all have the same repetitive job: register RAMBlocks with the BlockBackend using RAMBlockNotifier. Add a BlockRAMRegistrar API to do this. A later commit will use this from hw/block/virtio-blk.c. Signed-off-by: Stefan Hajnoczi --- MAINTAINERS | 1 + include/sysemu/block-ram-registrar.h | 30 +++++++++++++++++++++ block/block-ram-registrar.c | 39 ++++++++++++++++++++++++++++ block/meson.build | 1 + 4 files changed, 71 insertions(+) create mode 100644 include/sysemu/block-ram-registrar.h create mode 100644 block/block-ram-registrar.c diff --git a/MAINTAINERS b/MAINTAINERS index 0fb08dd4f7..da6ec4d79b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2462,6 +2462,7 @@ F: block* F: block/ F: hw/block/ F: include/block/ +F: include/sysemu/block-*.h F: qemu-img* F: docs/tools/qemu-img.rst F: qemu-io* diff --git a/include/sysemu/block-ram-registrar.h b/include/sysemu/block-ra= m-registrar.h new file mode 100644 index 0000000000..09d63f64b2 --- /dev/null +++ b/include/sysemu/block-ram-registrar.h @@ -0,0 +1,30 @@ +/* + * BlockBackend RAM Registrar + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef BLOCK_RAM_REGISTRAR_H +#define BLOCK_RAM_REGISTRAR_H + +#include "exec/ramlist.h" + +/** + * struct BlockRAMRegistrar: + * + * Keeps RAMBlock memory registered with a BlockBackend using + * blk_register_buf() including hotplugged memory. + * + * Emulated devices or other BlockBackend users initialize a BlockRAMRegis= trar + * with blk_ram_registrar_init() before submitting I/O requests with the + * BLK_REQ_REGISTERED_BUF flag set. + */ +typedef struct { + BlockBackend *blk; + RAMBlockNotifier notifier; +} BlockRAMRegistrar; + +void blk_ram_registrar_init(BlockRAMRegistrar *r, BlockBackend *blk); +void blk_ram_registrar_destroy(BlockRAMRegistrar *r); + +#endif /* BLOCK_RAM_REGISTRAR_H */ diff --git a/block/block-ram-registrar.c b/block/block-ram-registrar.c new file mode 100644 index 0000000000..32a14b69ae --- /dev/null +++ b/block/block-ram-registrar.c @@ -0,0 +1,39 @@ +/* + * BlockBackend RAM Registrar + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "sysemu/block-backend.h" +#include "sysemu/block-ram-registrar.h" + +static void ram_block_added(RAMBlockNotifier *n, void *host, size_t size, + size_t max_size) +{ + BlockRAMRegistrar *r =3D container_of(n, BlockRAMRegistrar, notifier); + blk_register_buf(r->blk, host, max_size); +} + +static void ram_block_removed(RAMBlockNotifier *n, void *host, size_t size, + size_t max_size) +{ + BlockRAMRegistrar *r =3D container_of(n, BlockRAMRegistrar, notifier); + blk_unregister_buf(r->blk, host, max_size); +} + +void blk_ram_registrar_init(BlockRAMRegistrar *r, BlockBackend *blk) +{ + r->blk =3D blk; + r->notifier =3D (RAMBlockNotifier){ + .ram_block_added =3D ram_block_added, + .ram_block_removed =3D ram_block_removed, + }; + + ram_block_notifier_add(&r->notifier); +} + +void blk_ram_registrar_destroy(BlockRAMRegistrar *r) +{ + ram_block_notifier_remove(&r->notifier); +} diff --git a/block/meson.build b/block/meson.build index 787667384a..b315593054 100644 --- a/block/meson.build +++ b/block/meson.build @@ -46,6 +46,7 @@ block_ss.add(files( ), zstd, zlib, gnutls) =20 softmmu_ss.add(when: 'CONFIG_TCG', if_true: files('blkreplay.c')) +softmmu_ss.add(files('block-ram-registrar.c')) =20 if get_option('qcow1').allowed() block_ss.add(files('qcow.c')) --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648035064315934.446531769798; Wed, 23 Mar 2022 04:31:04 -0700 (PDT) Received: from localhost ([::1]:37192 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWzCi-0008NR-Th for importer@patchew.org; Wed, 23 Mar 2022 07:31:04 -0400 Received: from eggs.gnu.org ([209.51.188.92]:37102) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWz02-00016t-VQ for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:21930) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWz00-0002Pv-79 for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:58 -0400 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-515-qYnK_2vfMROdJMVxiAxeZA-1; Wed, 23 Mar 2022 07:17:52 -0400 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 00BFC811E76; Wed, 23 Mar 2022 11:17:52 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2E0E3112132C; Wed, 23 Mar 2022 11:17:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034275; 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=5Uq7DE7cZO1deQaJbvM3lIszCBeQOVFN9M1aTfL+W9A=; b=h4bAfmNF7qz1Y08fPaz95hI9ubY3+FdkqmiGX6HTrONKNmFhQSZ3SrgHwJl42RBfHwIB1q 2VGiOwpsb9/jErh6fcM0IzoSoUX/AVVExTuU668h8y9TvZ7ZISC9029Lza5w0h5Sj1NtWb ai1pSBxfKGld7+btBXDshjelL+pRAW4= X-MC-Unique: qYnK_2vfMROdJMVxiAxeZA-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 6/8] stubs: add memory_region_from_host() and memory_region_get_fd() Date: Wed, 23 Mar 2022 11:17:25 +0000 Message-Id: <20220323111727.1100209-7-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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, T_SCC_BODY_TEXT_LINE=-0.01 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648035087860100001 Content-Type: text/plain; charset="utf-8" The blkio block driver will need to look up the file descriptor for a given pointer. This is possible in softmmu builds where the memory API is available for querying guest RAM. Add stubs so tools like qemu-img that link the block layer still build successfully. In this case there is no guest RAM but that is fine. Bounce buffers and their file descriptors will be allocated with libblkio's blkio_alloc_mem_region() so we won't rely on QEMU's memory_region_get_fd() in that case. Signed-off-by: Stefan Hajnoczi --- stubs/memory.c | 13 +++++++++++++ stubs/meson.build | 1 + 2 files changed, 14 insertions(+) create mode 100644 stubs/memory.c diff --git a/stubs/memory.c b/stubs/memory.c new file mode 100644 index 0000000000..e9ec4e384b --- /dev/null +++ b/stubs/memory.c @@ -0,0 +1,13 @@ +#include "qemu/osdep.h" +#include "exec/memory.h" + +MemoryRegion *memory_region_from_host(void *host, ram_addr_t *offset) +{ + return NULL; +} + +int memory_region_get_fd(MemoryRegion *mr) +{ + return -1; +} + diff --git a/stubs/meson.build b/stubs/meson.build index 6f80fec761..1e274d2db2 100644 --- a/stubs/meson.build +++ b/stubs/meson.build @@ -25,6 +25,7 @@ stub_ss.add(files('is-daemonized.c')) if libaio.found() stub_ss.add(files('linux-aio.c')) endif +stub_ss.add(files('memory.c')) stub_ss.add(files('migr-blocker.c')) stub_ss.add(files('module-opts.c')) stub_ss.add(files('monitor.c')) --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1648034883690880.6549252536413; Wed, 23 Mar 2022 04:28:03 -0700 (PDT) Received: from localhost ([::1]:56798 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWz9m-0002Yp-Gg for importer@patchew.org; Wed, 23 Mar 2022 07:28:02 -0400 Received: from eggs.gnu.org ([209.51.188.92]:37074) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWz01-00016r-O3 for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:29211) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWyzz-0002Pr-VE for qemu-devel@nongnu.org; Wed, 23 Mar 2022 07:17:57 -0400 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-536-f98vVDZhNQyUO9AONga3SA-1; Wed, 23 Mar 2022 07:17:54 -0400 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B7CD9802809; Wed, 23 Mar 2022 11:17:53 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4D7AF565DBD; Wed, 23 Mar 2022 11:17:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034275; 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=zquN7zevoWdWPGg9D4ZbVKxJqDbEcY0jrX91R7b2DmQ=; b=iHSGCs0N/NplD/QXYNCmt2qHXn6loc1W3/CW+B22rvmqLxq3znEDuha7Wc1xNwMhQGikxV gJxUxpw1zxoPGyK7cJuqDt1c931siw6cXYfbMrMPTpm93qOGJJOLGcjiZIQqSgHLbq+cRv ktldMlmzzdEla925Zd3ExaAGaIy3yog= X-MC-Unique: f98vVDZhNQyUO9AONga3SA-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 7/8] blkio: implement BDRV_REQ_REGISTERED_BUF optimization Date: Wed, 23 Mar 2022 11:17:26 +0000 Message-Id: <20220323111727.1100209-8-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648034885242100001 Content-Type: text/plain; charset="utf-8" Avoid bounce buffers when QEMUIOVector elements are within previously registered bdrv_register_buf() buffers. The idea is that emulated storage controllers will register guest RAM using bdrv_register_buf() and set the BDRV_REQ_REGISTERED_BUF on I/O requests. Therefore no blkio_add_mem_region() calls are necessary in the performance-critical I/O code path. This optimization doesn't apply if the I/O buffer is internally allocated by QEMU (e.g. qcow2 metadata). There we still take the slow path because BDRV_REQ_REGISTERED_BUF is not set. Signed-off-by: Stefan Hajnoczi --- block/blkio.c | 108 ++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 104 insertions(+), 4 deletions(-) diff --git a/block/blkio.c b/block/blkio.c index dd2308b967..78f4ca5f49 100644 --- a/block/blkio.c +++ b/block/blkio.c @@ -1,7 +1,9 @@ #include "qemu/osdep.h" #include #include "block/block_int.h" +#include "exec/memory.h" #include "qapi/error.h" +#include "qemu/error-report.h" #include "qapi/qmp/qdict.h" #include "qemu/module.h" =20 @@ -26,6 +28,9 @@ typedef struct { /* Can we skip adding/deleting blkio_mem_regions? */ bool needs_mem_regions; =20 + /* Are file descriptors necessary for blkio_mem_regions? */ + bool needs_mem_region_fd; + /* * blkio_completion_fd_poll() stashes the next completion for * blkio_completion_fd_poll_ready(). @@ -170,6 +175,8 @@ static BlockAIOCB *blkio_aio_preadv(BlockDriverState *b= s, int64_t offset, BlockCompletionFunc *cb, void *opaque) { BDRVBlkioState *s =3D bs->opaque; + bool needs_mem_regions =3D + s->needs_mem_regions && !(flags & BDRV_REQ_REGISTERED_BUF); struct iovec *iov =3D qiov->iov; int iovcnt =3D qiov->niov; BlkioAIOCB *acb; @@ -179,7 +186,7 @@ static BlockAIOCB *blkio_aio_preadv(BlockDriverState *b= s, int64_t offset, =20 acb =3D blkio_aiocb_get(bs, cb, opaque); =20 - if (s->needs_mem_regions) { + if (needs_mem_regions) { if (blkio_aiocb_init_mem_region_locked(acb, bytes) < 0) { qemu_aio_unref(&acb->common); return NULL; @@ -194,7 +201,7 @@ static BlockAIOCB *blkio_aio_preadv(BlockDriverState *b= s, int64_t offset, =20 ret =3D blkioq_readv(s->blkioq, offset, iov, iovcnt, acb, 0); if (ret < 0) { - if (s->needs_mem_regions) { + if (needs_mem_regions) { blkio_free_mem_region(s->blkio, &acb->mem_region); qemu_iovec_destroy(&acb->qiov); } @@ -215,6 +222,8 @@ static BlockAIOCB *blkio_aio_pwritev(BlockDriverState *= bs, int64_t offset, { uint32_t blkio_flags =3D (flags & BDRV_REQ_FUA) ? BLKIO_REQ_FUA : 0; BDRVBlkioState *s =3D bs->opaque; + bool needs_mem_regions =3D + s->needs_mem_regions && !(flags & BDRV_REQ_REGISTERED_BUF); struct iovec *iov =3D qiov->iov; int iovcnt =3D qiov->niov; BlkioAIOCB *acb; @@ -224,7 +233,7 @@ static BlockAIOCB *blkio_aio_pwritev(BlockDriverState *= bs, int64_t offset, =20 acb =3D blkio_aiocb_get(bs, cb, opaque); =20 - if (s->needs_mem_regions) { + if (needs_mem_regions) { if (blkio_aiocb_init_mem_region_locked(acb, bytes) < 0) { qemu_aio_unref(&acb->common); return NULL; @@ -238,7 +247,7 @@ static BlockAIOCB *blkio_aio_pwritev(BlockDriverState *= bs, int64_t offset, =20 ret =3D blkioq_writev(s->blkioq, offset, iov, iovcnt, acb, blkio_flags= ); if (ret < 0) { - if (s->needs_mem_regions) { + if (needs_mem_regions) { blkio_free_mem_region(s->blkio, &acb->mem_region); } qemu_aio_unref(&acb->common); @@ -286,6 +295,83 @@ static void blkio_io_unplug(BlockDriverState *bs) } } =20 +static void blkio_register_buf(BlockDriverState *bs, void *host, size_t si= ze) +{ + BDRVBlkioState *s =3D bs->opaque; + char *errmsg; + int ret; + struct blkio_mem_region region =3D (struct blkio_mem_region){ + .addr =3D host, + .len =3D size, + .fd =3D -1, + }; + + if (((uintptr_t)host | size) % s->mem_region_alignment) { + error_report_once("%s: skipping unaligned buf %p with size %zu", + __func__, host, size); + return; /* skip unaligned */ + } + + /* Attempt to find the fd for a MemoryRegion */ + if (s->needs_mem_region_fd) { + int fd =3D -1; + ram_addr_t offset; + MemoryRegion *mr; + + /* + * bdrv_register_buf() is called with the BQL held so mr lives at = least + * until this function returns. + */ + mr =3D memory_region_from_host(host, &offset); + if (mr) { + fd =3D memory_region_get_fd(mr); + } + if (fd =3D=3D -1) { + error_report_once("%s: skipping fd-less buf %p with size %zu", + __func__, host, size); + return; /* skip if there is no fd */ + } + + region.fd =3D fd; + region.fd_offset =3D offset; + } + + WITH_QEMU_LOCK_GUARD(&s->lock) { + ret =3D blkio_add_mem_region(s->blkio, ®ion, &errmsg); + } + + if (ret < 0) { + error_report_once("Failed to add blkio mem region %p with size %zu= : %s", + host, size, errmsg); + free(errmsg); + } +} + +static void blkio_unregister_buf(BlockDriverState *bs, void *host, size_t = size) +{ + BDRVBlkioState *s =3D bs->opaque; + char *errmsg; + int ret; + struct blkio_mem_region region =3D (struct blkio_mem_region){ + .addr =3D host, + .len =3D size, + }; + + if (((uintptr_t)host | size) % s->mem_region_alignment) { + return; /* skip unaligned */ + } + + WITH_QEMU_LOCK_GUARD(&s->lock) { + ret =3D blkio_del_mem_region(s->blkio, ®ion, &errmsg); + } + + if (ret < 0) { + error_report_once("Failed to delete blkio mem region %p with size = %zu: %s", + host, size, errmsg); + free(errmsg); + } +} + static void blkio_parse_filename_io_uring(const char *filename, QDict *opt= ions, Error **errp) { @@ -356,6 +442,18 @@ static int blkio_file_open(BlockDriverState *bs, QDict= *options, int flags, return ret; } =20 + ret =3D blkio_get_bool(s->blkio, + "needs-mem-region-fd", + &s->needs_mem_region_fd, + &errmsg); + if (ret < 0) { + error_setg_errno(errp, -ret, + "failed to get needs-mem-region-fd: %s", errmsg); + free(errmsg); + blkio_destroy(&s->blkio); + return ret; + } + ret =3D blkio_get_uint64(s->blkio, "mem-region-alignment", &s->mem_region_alignment, @@ -436,6 +534,8 @@ static BlockDriver bdrv_io_uring =3D { .bdrv_aio_pwritev =3D blkio_aio_pwritev, .bdrv_aio_flush =3D blkio_aio_flush, .bdrv_io_unplug =3D blkio_io_unplug, + .bdrv_register_buf =3D blkio_register_buf, + .bdrv_unregister_buf =3D blkio_unregister_buf, =20 /* * TODO --=20 2.35.1 From nobody Mon Feb 9 05:39:04 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 16480358686871009.9664977871709; 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Wed, 23 Mar 2022 11:17:55 +0000 (UTC) Received: from localhost (unknown [10.39.194.72]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0E285C202C9; Wed, 23 Mar 2022 11:17:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648034278; 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=F3waz1XxSna8I1NMy3FXUIuiSf9xvwgpbuZPM3PrpW0=; b=eKwSq7usU7pdYOn0MXB7C5xFAnOZNBYE7TGhqlDSYaRVQf6eHUk+eURPEjh/4VneWcuxVp R43ZRyuPB9CX+fhsf2UDj+jcKmaHtv5zyR2BzpjcrxDzhWmQiPKf9IBs0B8PniNv9iOSr1 Li7Tb0MUMLSWMwGMoVqwVxI9B84ib8E= X-MC-Unique: DQ08-1u7OCqYWxm6y_PIPQ-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [RFC 8/8] virtio-blk: use BDRV_REQ_REGISTERED_BUF optimization hint Date: Wed, 23 Mar 2022 11:17:27 +0000 Message-Id: <20220323111727.1100209-9-stefanha@redhat.com> In-Reply-To: <20220323111727.1100209-1-stefanha@redhat.com> References: <20220323111727.1100209-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.8 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham 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: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Michael S. Tsirkin" , John Snow , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Alberto Faria , Markus Armbruster , Yanan Wang , Eduardo Habkost , Hanna Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Eric Blake , sgarzare@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648035872005100001 Content-Type: text/plain; charset="utf-8" Register guest RAM using BlockRAMRegistrar and set the BDRV_REQ_REGISTERED_BUF flag so block drivers can optimize memory accesses in I/O requests. This is for vdpa-blk, vhost-user-blk, and other I/O interfaces that rely on DMA mapping/unmapping. Signed-off-by: Stefan Hajnoczi --- include/hw/virtio/virtio-blk.h | 2 ++ hw/block/virtio-blk.c | 13 +++++++++---- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index d311c57cca..7f589b4146 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -19,6 +19,7 @@ #include "hw/block/block.h" #include "sysemu/iothread.h" #include "sysemu/block-backend.h" +#include "sysemu/block-ram-registrar.h" #include "qom/object.h" =20 #define TYPE_VIRTIO_BLK "virtio-blk-device" @@ -64,6 +65,7 @@ struct VirtIOBlock { struct VirtIOBlockDataPlane *dataplane; uint64_t host_features; size_t config_size; + BlockRAMRegistrar blk_ram_registrar; }; =20 typedef struct VirtIOBlockReq { diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 540c38f829..a18cf05f14 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -21,6 +21,7 @@ #include "hw/block/block.h" #include "hw/qdev-properties.h" #include "sysemu/blockdev.h" +#include "sysemu/block-ram-registrar.h" #include "sysemu/sysemu.h" #include "sysemu/runstate.h" #include "hw/virtio/virtio-blk.h" @@ -421,11 +422,13 @@ static inline void submit_requests(BlockBackend *blk,= MultiReqBuffer *mrb, } =20 if (is_write) { - blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, - virtio_blk_rw_complete, mrb->reqs[start]); + blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, + BDRV_REQ_REGISTERED_BUF, virtio_blk_rw_complete, + mrb->reqs[start]); } else { - blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, - virtio_blk_rw_complete, mrb->reqs[start]); + blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, + BDRV_REQ_REGISTERED_BUF, virtio_blk_rw_complete, + mrb->reqs[start]); } } =20 @@ -1228,6 +1231,7 @@ static void virtio_blk_device_realize(DeviceState *de= v, Error **errp) } =20 s->change =3D qemu_add_vm_change_state_handler(virtio_blk_dma_restart_= cb, s); + blk_ram_registrar_init(&s->blk_ram_registrar, s->blk); blk_set_dev_ops(s->blk, &virtio_block_ops, s); blk_set_guest_block_size(s->blk, s->conf.conf.logical_block_size); =20 @@ -1255,6 +1259,7 @@ static void virtio_blk_device_unrealize(DeviceState *= dev) } qemu_coroutine_decrease_pool_batch_size(conf->num_queues * conf->queue= _size / 2); + blk_ram_registrar_destroy(&s->blk_ram_registrar); qemu_del_vm_change_state_handler(s->change); blockdev_mark_auto_del(s->blk); virtio_cleanup(vdev); --=20 2.35.1