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Tsirkin" To: Christian Schoenebeck Subject: Re: [PATCH v2 2/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k Message-ID: <20211005031333-mutt-send-email-mst@kernel.org> References: MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mst@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=216.205.24.124; envelope-from=mst@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.066, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Laurent Vivier , qemu-block@nongnu.org, Amit Shah , Jason Wang , David Hildenbrand , qemu-devel@nongnu.org, Raphael Norwitz , virtio-fs@redhat.com, Eric Auger , Hanna Reitz , "Gonglei \(Arei\)" , Gerd Hoffmann , Stefan Hajnoczi , Paolo Bonzini , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Fam Zheng , "Dr. David Alan Gilbert" , Greg Kurz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Oct 04, 2021 at 09:38:08PM +0200, Christian Schoenebeck wrote: > Raise the maximum possible virtio transfer size to 128M > (more precisely: 32k * PAGE_SIZE). See previous commit for a > more detailed explanation for the reasons of this change. > > For not breaking any virtio user, all virtio users transition > to using the new macro VIRTQUEUE_LEGACY_MAX_SIZE instead of > VIRTQUEUE_MAX_SIZE, so they are all still using the old value > of 1k with this commit. > > On the long-term, each virtio user should subsequently either > switch from VIRTQUEUE_LEGACY_MAX_SIZE to VIRTQUEUE_MAX_SIZE > after checking that they support the new value of 32k, or > otherwise they should replace the VIRTQUEUE_LEGACY_MAX_SIZE > macro by an appropriate value supported by them. > > Signed-off-by: Christian Schoenebeck I don't think we need this. Legacy isn't descriptive either. Just leave VIRTQUEUE_MAX_SIZE alone, and come up with a new name for 32k. > --- > hw/9pfs/virtio-9p-device.c | 2 +- > hw/block/vhost-user-blk.c | 6 +++--- > hw/block/virtio-blk.c | 6 +++--- > hw/char/virtio-serial-bus.c | 2 +- > hw/input/virtio-input.c | 2 +- > hw/net/virtio-net.c | 12 ++++++------ > hw/scsi/virtio-scsi.c | 2 +- > hw/virtio/vhost-user-fs.c | 6 +++--- > hw/virtio/vhost-user-i2c.c | 2 +- > hw/virtio/vhost-vsock-common.c | 2 +- > hw/virtio/virtio-balloon.c | 2 +- > hw/virtio/virtio-crypto.c | 2 +- > hw/virtio/virtio-iommu.c | 2 +- > hw/virtio/virtio-mem.c | 2 +- > hw/virtio/virtio-mmio.c | 4 ++-- > hw/virtio/virtio-pmem.c | 2 +- > hw/virtio/virtio-rng.c | 3 ++- > include/hw/virtio/virtio.h | 20 +++++++++++++++++++- > 18 files changed, 49 insertions(+), 30 deletions(-) > > diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c > index cd5d95dd51..9013e7df6e 100644 > --- a/hw/9pfs/virtio-9p-device.c > +++ b/hw/9pfs/virtio-9p-device.c > @@ -217,7 +217,7 @@ static void virtio_9p_device_realize(DeviceState *dev, Error **errp) > > v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag); > virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output); > } > > diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c > index 336f56705c..e5e45262ab 100644 > --- a/hw/block/vhost-user-blk.c > +++ b/hw/block/vhost-user-blk.c > @@ -480,9 +480,9 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp) > error_setg(errp, "queue size must be non-zero"); > return; > } > - if (s->queue_size > VIRTQUEUE_MAX_SIZE) { > + if (s->queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) { > error_setg(errp, "queue size must not exceed %d", > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > return; > } > > @@ -491,7 +491,7 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, > - sizeof(struct virtio_blk_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_blk_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > s->virtqs = g_new(VirtQueue *, s->num_queues); > for (i = 0; i < s->num_queues; i++) { > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > index 9c0f46815c..5883e3e7db 100644 > --- a/hw/block/virtio-blk.c > +++ b/hw/block/virtio-blk.c > @@ -1171,10 +1171,10 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) > return; > } > if (!is_power_of_2(conf->queue_size) || > - conf->queue_size > VIRTQUEUE_MAX_SIZE) { > + conf->queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) { > error_setg(errp, "invalid queue-size property (%" PRIu16 "), " > "must be a power of 2 (max %d)", > - conf->queue_size, VIRTQUEUE_MAX_SIZE); > + conf->queue_size, VIRTQUEUE_LEGACY_MAX_SIZE); > return; > } > > @@ -1214,7 +1214,7 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) > virtio_blk_set_config_size(s, s->host_features); > > virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > > s->blk = conf->conf.blk; > s->rq = NULL; > diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c > index 9ad9111115..2d4285ab53 100644 > --- a/hw/char/virtio-serial-bus.c > +++ b/hw/char/virtio-serial-bus.c > @@ -1045,7 +1045,7 @@ static void virtio_serial_device_realize(DeviceState *dev, Error **errp) > config_size = offsetof(struct virtio_console_config, emerg_wr); > } > virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE, > - config_size, VIRTQUEUE_MAX_SIZE); > + config_size, VIRTQUEUE_LEGACY_MAX_SIZE); > > /* Spawn a new virtio-serial bus on which the ports will ride as devices */ > qbus_init(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS, > diff --git a/hw/input/virtio-input.c b/hw/input/virtio-input.c > index 345eb2cce7..b6b77488f2 100644 > --- a/hw/input/virtio-input.c > +++ b/hw/input/virtio-input.c > @@ -258,7 +258,7 @@ static void virtio_input_device_realize(DeviceState *dev, Error **errp) > assert(vinput->cfg_size <= sizeof(virtio_input_config)); > > virtio_init(vdev, "virtio-input", VIRTIO_ID_INPUT, > - vinput->cfg_size, VIRTQUEUE_MAX_SIZE); > + vinput->cfg_size, VIRTQUEUE_LEGACY_MAX_SIZE); > vinput->evt = virtio_add_queue(vdev, 64, virtio_input_handle_evt); > vinput->sts = virtio_add_queue(vdev, 64, virtio_input_handle_sts); > } > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index f74b5f6268..5100978b07 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -636,7 +636,7 @@ static int virtio_net_max_tx_queue_size(VirtIONet *n) > return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE; > } > > - return VIRTQUEUE_MAX_SIZE; > + return VIRTQUEUE_LEGACY_MAX_SIZE; > } > > static int peer_attach(VirtIONet *n, int index) > @@ -3365,7 +3365,7 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > > virtio_net_set_config_size(n, n->host_features); > virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > > /* > * We set a lower limit on RX queue size to what it always was. > @@ -3373,23 +3373,23 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > * help from us (using virtio 1 and up). > */ > if (n->net_conf.rx_queue_size < VIRTIO_NET_RX_QUEUE_MIN_SIZE || > - n->net_conf.rx_queue_size > VIRTQUEUE_MAX_SIZE || > + n->net_conf.rx_queue_size > VIRTQUEUE_LEGACY_MAX_SIZE || > !is_power_of_2(n->net_conf.rx_queue_size)) { > error_setg(errp, "Invalid rx_queue_size (= %" PRIu16 "), " > "must be a power of 2 between %d and %d.", > n->net_conf.rx_queue_size, VIRTIO_NET_RX_QUEUE_MIN_SIZE, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > virtio_cleanup(vdev); > return; > } > > if (n->net_conf.tx_queue_size < VIRTIO_NET_TX_QUEUE_MIN_SIZE || > - n->net_conf.tx_queue_size > VIRTQUEUE_MAX_SIZE || > + n->net_conf.tx_queue_size > VIRTQUEUE_LEGACY_MAX_SIZE || > !is_power_of_2(n->net_conf.tx_queue_size)) { > error_setg(errp, "Invalid tx_queue_size (= %" PRIu16 "), " > "must be a power of 2 between %d and %d", > n->net_conf.tx_queue_size, VIRTIO_NET_TX_QUEUE_MIN_SIZE, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > virtio_cleanup(vdev); > return; > } > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c > index 5e5e657e1d..f204e8878a 100644 > --- a/hw/scsi/virtio-scsi.c > +++ b/hw/scsi/virtio-scsi.c > @@ -973,7 +973,7 @@ void virtio_scsi_common_realize(DeviceState *dev, > int i; > > virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI, > - sizeof(VirtIOSCSIConfig), VIRTQUEUE_MAX_SIZE); > + sizeof(VirtIOSCSIConfig), VIRTQUEUE_LEGACY_MAX_SIZE); > > if (s->conf.num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) { > s->conf.num_queues = 1; > diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c > index ae1672d667..decc5def39 100644 > --- a/hw/virtio/vhost-user-fs.c > +++ b/hw/virtio/vhost-user-fs.c > @@ -209,9 +209,9 @@ static void vuf_device_realize(DeviceState *dev, Error **errp) > return; > } > > - if (fs->conf.queue_size > VIRTQUEUE_MAX_SIZE) { > + if (fs->conf.queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) { > error_setg(errp, "queue-size property must be %u or smaller", > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > return; > } > > @@ -220,7 +220,7 @@ static void vuf_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "vhost-user-fs", VIRTIO_ID_FS, > - sizeof(struct virtio_fs_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_fs_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > /* Hiprio queue */ > fs->hiprio_vq = virtio_add_queue(vdev, fs->conf.queue_size, vuf_handle_output); > diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c > index eeb1d8853a..b248ddbe93 100644 > --- a/hw/virtio/vhost-user-i2c.c > +++ b/hw/virtio/vhost-user-i2c.c > @@ -221,7 +221,7 @@ static void vu_i2c_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > > i2c->vhost_dev.nvqs = 1; > i2c->vq = virtio_add_queue(vdev, 4, vu_i2c_handle_output); > diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c > index a81fa884a8..73e6b72bba 100644 > --- a/hw/virtio/vhost-vsock-common.c > +++ b/hw/virtio/vhost-vsock-common.c > @@ -201,7 +201,7 @@ void vhost_vsock_common_realize(VirtIODevice *vdev, const char *name) > VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); > > virtio_init(vdev, name, VIRTIO_ID_VSOCK, > - sizeof(struct virtio_vsock_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_vsock_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > /* Receive and transmit queues belong to vhost */ > vvc->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE, > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index 067c73223d..890fb15ed3 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -886,7 +886,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) > int ret; > > virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON, > - virtio_balloon_config_size(s), VIRTQUEUE_MAX_SIZE); > + virtio_balloon_config_size(s), VIRTQUEUE_LEGACY_MAX_SIZE); > > ret = qemu_add_balloon_handler(virtio_balloon_to_target, > virtio_balloon_stat, s); > diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c > index 1e70d4d2a8..e13b6091d6 100644 > --- a/hw/virtio/virtio-crypto.c > +++ b/hw/virtio/virtio-crypto.c > @@ -811,7 +811,7 @@ static void virtio_crypto_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "virtio-crypto", VIRTIO_ID_CRYPTO, vcrypto->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > vcrypto->curr_queues = 1; > vcrypto->vqs = g_malloc0(sizeof(VirtIOCryptoQueue) * vcrypto->max_queues); > for (i = 0; i < vcrypto->max_queues; i++) { > diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c > index ca360e74eb..845df78842 100644 > --- a/hw/virtio/virtio-iommu.c > +++ b/hw/virtio/virtio-iommu.c > @@ -974,7 +974,7 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp) > VirtIOIOMMU *s = VIRTIO_IOMMU(dev); > > virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU, > - sizeof(struct virtio_iommu_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_iommu_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > memset(s->iommu_pcibus_by_bus_num, 0, sizeof(s->iommu_pcibus_by_bus_num)); > > diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c > index 1d9d01b871..7a39550cde 100644 > --- a/hw/virtio/virtio-mem.c > +++ b/hw/virtio/virtio-mem.c > @@ -738,7 +738,7 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) > vmem->bitmap = bitmap_new(vmem->bitmap_size); > > virtio_init(vdev, TYPE_VIRTIO_MEM, VIRTIO_ID_MEM, > - sizeof(struct virtio_mem_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_mem_config), VIRTQUEUE_LEGACY_MAX_SIZE); > vmem->vq = virtio_add_queue(vdev, 128, virtio_mem_handle_request); > > host_memory_backend_set_mapped(vmem->memdev, true); > diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c > index 7b3ebca178..ae0cc223e9 100644 > --- a/hw/virtio/virtio-mmio.c > +++ b/hw/virtio/virtio-mmio.c > @@ -174,7 +174,7 @@ static uint64_t virtio_mmio_read(void *opaque, hwaddr offset, unsigned size) > if (!virtio_queue_get_num(vdev, vdev->queue_sel)) { > return 0; > } > - return VIRTQUEUE_MAX_SIZE; > + return VIRTQUEUE_LEGACY_MAX_SIZE; > case VIRTIO_MMIO_QUEUE_PFN: > if (!proxy->legacy) { > qemu_log_mask(LOG_GUEST_ERROR, > @@ -348,7 +348,7 @@ static void virtio_mmio_write(void *opaque, hwaddr offset, uint64_t value, > } > break; > case VIRTIO_MMIO_QUEUE_NUM: > - trace_virtio_mmio_queue_write(value, VIRTQUEUE_MAX_SIZE); > + trace_virtio_mmio_queue_write(value, VIRTQUEUE_LEGACY_MAX_SIZE); > virtio_queue_set_num(vdev, vdev->queue_sel, value); > > if (proxy->legacy) { > diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c > index 82b54b00c5..5f4d375b58 100644 > --- a/hw/virtio/virtio-pmem.c > +++ b/hw/virtio/virtio-pmem.c > @@ -124,7 +124,7 @@ static void virtio_pmem_realize(DeviceState *dev, Error **errp) > > host_memory_backend_set_mapped(pmem->memdev, true); > virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM, > - sizeof(struct virtio_pmem_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_pmem_config), VIRTQUEUE_LEGACY_MAX_SIZE); > pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush); > } > > diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c > index 0e91d60106..ab075b22b6 100644 > --- a/hw/virtio/virtio-rng.c > +++ b/hw/virtio/virtio-rng.c > @@ -215,7 +215,8 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp) > return; > } > > - virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0, VIRTQUEUE_MAX_SIZE); > + virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0, > + VIRTQUEUE_LEGACY_MAX_SIZE); > > vrng->vq = virtio_add_queue(vdev, 8, handle_input); > vrng->quota_remaining = vrng->conf.max_bytes; > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index a37d1f7d52..fe0f13266b 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -48,7 +48,25 @@ size_t virtio_feature_get_config_size(const VirtIOFeature *features, > > typedef struct VirtQueue VirtQueue; > > -#define VIRTQUEUE_MAX_SIZE 1024 > +/* > + * This is meant as transitional measure for VIRTQUEUE_MAX_SIZE's old value > + * of 1024 to its new value of 32768. On the long-term virtio users should > + * either switch to VIRTQUEUE_MAX_SIZE, provided they support 32768, > + * otherwise they should replace this macro on their side with an > + * appropriate value actually supported by them. > + * > + * Once all virtio users switched, this macro will be removed. > + */ > +#define VIRTQUEUE_LEGACY_MAX_SIZE 1024 > + > +/* > + * Reflects the absolute theoretical maximum queue size (in amount of pages) > + * ever possible, which is actually the maximum queue size allowed by the > + * virtio protocol. This value therefore construes the maximum transfer size > + * possible with virtio (multiplied by system dependent PAGE_SIZE); assuming > + * a typical page size of 4k this would be a maximum transfer size of 128M. > + */ > +#define VIRTQUEUE_MAX_SIZE 32768 > > typedef struct VirtQueueElement > { > -- > 2.20.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 5 Oct 2021 03:16:07 -0400 From: "Michael S. Tsirkin" Message-ID: <20211005031333-mutt-send-email-mst@kernel.org> References: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: Re: [Virtio-fs] [PATCH v2 2/3] virtio: increase VIRTQUEUE_MAX_SIZE to 32k List-Id: Development discussions about virtio-fs List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Christian Schoenebeck Cc: Kevin Wolf , Laurent Vivier , qemu-block@nongnu.org, Amit Shah , Jason Wang , David Hildenbrand , qemu-devel@nongnu.org, Raphael Norwitz , virtio-fs@redhat.com, Eric Auger , Hanna Reitz , "Gonglei (Arei)" , Gerd Hoffmann , Paolo Bonzini , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Fam Zheng On Mon, Oct 04, 2021 at 09:38:08PM +0200, Christian Schoenebeck wrote: > Raise the maximum possible virtio transfer size to 128M > (more precisely: 32k * PAGE_SIZE). See previous commit for a > more detailed explanation for the reasons of this change. > > For not breaking any virtio user, all virtio users transition > to using the new macro VIRTQUEUE_LEGACY_MAX_SIZE instead of > VIRTQUEUE_MAX_SIZE, so they are all still using the old value > of 1k with this commit. > > On the long-term, each virtio user should subsequently either > switch from VIRTQUEUE_LEGACY_MAX_SIZE to VIRTQUEUE_MAX_SIZE > after checking that they support the new value of 32k, or > otherwise they should replace the VIRTQUEUE_LEGACY_MAX_SIZE > macro by an appropriate value supported by them. > > Signed-off-by: Christian Schoenebeck I don't think we need this. Legacy isn't descriptive either. Just leave VIRTQUEUE_MAX_SIZE alone, and come up with a new name for 32k. > --- > hw/9pfs/virtio-9p-device.c | 2 +- > hw/block/vhost-user-blk.c | 6 +++--- > hw/block/virtio-blk.c | 6 +++--- > hw/char/virtio-serial-bus.c | 2 +- > hw/input/virtio-input.c | 2 +- > hw/net/virtio-net.c | 12 ++++++------ > hw/scsi/virtio-scsi.c | 2 +- > hw/virtio/vhost-user-fs.c | 6 +++--- > hw/virtio/vhost-user-i2c.c | 2 +- > hw/virtio/vhost-vsock-common.c | 2 +- > hw/virtio/virtio-balloon.c | 2 +- > hw/virtio/virtio-crypto.c | 2 +- > hw/virtio/virtio-iommu.c | 2 +- > hw/virtio/virtio-mem.c | 2 +- > hw/virtio/virtio-mmio.c | 4 ++-- > hw/virtio/virtio-pmem.c | 2 +- > hw/virtio/virtio-rng.c | 3 ++- > include/hw/virtio/virtio.h | 20 +++++++++++++++++++- > 18 files changed, 49 insertions(+), 30 deletions(-) > > diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c > index cd5d95dd51..9013e7df6e 100644 > --- a/hw/9pfs/virtio-9p-device.c > +++ b/hw/9pfs/virtio-9p-device.c > @@ -217,7 +217,7 @@ static void virtio_9p_device_realize(DeviceState *dev, Error **errp) > > v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag); > virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output); > } > > diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c > index 336f56705c..e5e45262ab 100644 > --- a/hw/block/vhost-user-blk.c > +++ b/hw/block/vhost-user-blk.c > @@ -480,9 +480,9 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp) > error_setg(errp, "queue size must be non-zero"); > return; > } > - if (s->queue_size > VIRTQUEUE_MAX_SIZE) { > + if (s->queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) { > error_setg(errp, "queue size must not exceed %d", > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > return; > } > > @@ -491,7 +491,7 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, > - sizeof(struct virtio_blk_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_blk_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > s->virtqs = g_new(VirtQueue *, s->num_queues); > for (i = 0; i < s->num_queues; i++) { > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > index 9c0f46815c..5883e3e7db 100644 > --- a/hw/block/virtio-blk.c > +++ b/hw/block/virtio-blk.c > @@ -1171,10 +1171,10 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) > return; > } > if (!is_power_of_2(conf->queue_size) || > - conf->queue_size > VIRTQUEUE_MAX_SIZE) { > + conf->queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) { > error_setg(errp, "invalid queue-size property (%" PRIu16 "), " > "must be a power of 2 (max %d)", > - conf->queue_size, VIRTQUEUE_MAX_SIZE); > + conf->queue_size, VIRTQUEUE_LEGACY_MAX_SIZE); > return; > } > > @@ -1214,7 +1214,7 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) > virtio_blk_set_config_size(s, s->host_features); > > virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > > s->blk = conf->conf.blk; > s->rq = NULL; > diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c > index 9ad9111115..2d4285ab53 100644 > --- a/hw/char/virtio-serial-bus.c > +++ b/hw/char/virtio-serial-bus.c > @@ -1045,7 +1045,7 @@ static void virtio_serial_device_realize(DeviceState *dev, Error **errp) > config_size = offsetof(struct virtio_console_config, emerg_wr); > } > virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE, > - config_size, VIRTQUEUE_MAX_SIZE); > + config_size, VIRTQUEUE_LEGACY_MAX_SIZE); > > /* Spawn a new virtio-serial bus on which the ports will ride as devices */ > qbus_init(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS, > diff --git a/hw/input/virtio-input.c b/hw/input/virtio-input.c > index 345eb2cce7..b6b77488f2 100644 > --- a/hw/input/virtio-input.c > +++ b/hw/input/virtio-input.c > @@ -258,7 +258,7 @@ static void virtio_input_device_realize(DeviceState *dev, Error **errp) > assert(vinput->cfg_size <= sizeof(virtio_input_config)); > > virtio_init(vdev, "virtio-input", VIRTIO_ID_INPUT, > - vinput->cfg_size, VIRTQUEUE_MAX_SIZE); > + vinput->cfg_size, VIRTQUEUE_LEGACY_MAX_SIZE); > vinput->evt = virtio_add_queue(vdev, 64, virtio_input_handle_evt); > vinput->sts = virtio_add_queue(vdev, 64, virtio_input_handle_sts); > } > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index f74b5f6268..5100978b07 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -636,7 +636,7 @@ static int virtio_net_max_tx_queue_size(VirtIONet *n) > return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE; > } > > - return VIRTQUEUE_MAX_SIZE; > + return VIRTQUEUE_LEGACY_MAX_SIZE; > } > > static int peer_attach(VirtIONet *n, int index) > @@ -3365,7 +3365,7 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > > virtio_net_set_config_size(n, n->host_features); > virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > > /* > * We set a lower limit on RX queue size to what it always was. > @@ -3373,23 +3373,23 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > * help from us (using virtio 1 and up). > */ > if (n->net_conf.rx_queue_size < VIRTIO_NET_RX_QUEUE_MIN_SIZE || > - n->net_conf.rx_queue_size > VIRTQUEUE_MAX_SIZE || > + n->net_conf.rx_queue_size > VIRTQUEUE_LEGACY_MAX_SIZE || > !is_power_of_2(n->net_conf.rx_queue_size)) { > error_setg(errp, "Invalid rx_queue_size (= %" PRIu16 "), " > "must be a power of 2 between %d and %d.", > n->net_conf.rx_queue_size, VIRTIO_NET_RX_QUEUE_MIN_SIZE, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > virtio_cleanup(vdev); > return; > } > > if (n->net_conf.tx_queue_size < VIRTIO_NET_TX_QUEUE_MIN_SIZE || > - n->net_conf.tx_queue_size > VIRTQUEUE_MAX_SIZE || > + n->net_conf.tx_queue_size > VIRTQUEUE_LEGACY_MAX_SIZE || > !is_power_of_2(n->net_conf.tx_queue_size)) { > error_setg(errp, "Invalid tx_queue_size (= %" PRIu16 "), " > "must be a power of 2 between %d and %d", > n->net_conf.tx_queue_size, VIRTIO_NET_TX_QUEUE_MIN_SIZE, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > virtio_cleanup(vdev); > return; > } > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c > index 5e5e657e1d..f204e8878a 100644 > --- a/hw/scsi/virtio-scsi.c > +++ b/hw/scsi/virtio-scsi.c > @@ -973,7 +973,7 @@ void virtio_scsi_common_realize(DeviceState *dev, > int i; > > virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI, > - sizeof(VirtIOSCSIConfig), VIRTQUEUE_MAX_SIZE); > + sizeof(VirtIOSCSIConfig), VIRTQUEUE_LEGACY_MAX_SIZE); > > if (s->conf.num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) { > s->conf.num_queues = 1; > diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c > index ae1672d667..decc5def39 100644 > --- a/hw/virtio/vhost-user-fs.c > +++ b/hw/virtio/vhost-user-fs.c > @@ -209,9 +209,9 @@ static void vuf_device_realize(DeviceState *dev, Error **errp) > return; > } > > - if (fs->conf.queue_size > VIRTQUEUE_MAX_SIZE) { > + if (fs->conf.queue_size > VIRTQUEUE_LEGACY_MAX_SIZE) { > error_setg(errp, "queue-size property must be %u or smaller", > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > return; > } > > @@ -220,7 +220,7 @@ static void vuf_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "vhost-user-fs", VIRTIO_ID_FS, > - sizeof(struct virtio_fs_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_fs_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > /* Hiprio queue */ > fs->hiprio_vq = virtio_add_queue(vdev, fs->conf.queue_size, vuf_handle_output); > diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c > index eeb1d8853a..b248ddbe93 100644 > --- a/hw/virtio/vhost-user-i2c.c > +++ b/hw/virtio/vhost-user-i2c.c > @@ -221,7 +221,7 @@ static void vu_i2c_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > > i2c->vhost_dev.nvqs = 1; > i2c->vq = virtio_add_queue(vdev, 4, vu_i2c_handle_output); > diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c > index a81fa884a8..73e6b72bba 100644 > --- a/hw/virtio/vhost-vsock-common.c > +++ b/hw/virtio/vhost-vsock-common.c > @@ -201,7 +201,7 @@ void vhost_vsock_common_realize(VirtIODevice *vdev, const char *name) > VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); > > virtio_init(vdev, name, VIRTIO_ID_VSOCK, > - sizeof(struct virtio_vsock_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_vsock_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > /* Receive and transmit queues belong to vhost */ > vvc->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE, > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index 067c73223d..890fb15ed3 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -886,7 +886,7 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) > int ret; > > virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON, > - virtio_balloon_config_size(s), VIRTQUEUE_MAX_SIZE); > + virtio_balloon_config_size(s), VIRTQUEUE_LEGACY_MAX_SIZE); > > ret = qemu_add_balloon_handler(virtio_balloon_to_target, > virtio_balloon_stat, s); > diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c > index 1e70d4d2a8..e13b6091d6 100644 > --- a/hw/virtio/virtio-crypto.c > +++ b/hw/virtio/virtio-crypto.c > @@ -811,7 +811,7 @@ static void virtio_crypto_device_realize(DeviceState *dev, Error **errp) > } > > virtio_init(vdev, "virtio-crypto", VIRTIO_ID_CRYPTO, vcrypto->config_size, > - VIRTQUEUE_MAX_SIZE); > + VIRTQUEUE_LEGACY_MAX_SIZE); > vcrypto->curr_queues = 1; > vcrypto->vqs = g_malloc0(sizeof(VirtIOCryptoQueue) * vcrypto->max_queues); > for (i = 0; i < vcrypto->max_queues; i++) { > diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c > index ca360e74eb..845df78842 100644 > --- a/hw/virtio/virtio-iommu.c > +++ b/hw/virtio/virtio-iommu.c > @@ -974,7 +974,7 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp) > VirtIOIOMMU *s = VIRTIO_IOMMU(dev); > > virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU, > - sizeof(struct virtio_iommu_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_iommu_config), VIRTQUEUE_LEGACY_MAX_SIZE); > > memset(s->iommu_pcibus_by_bus_num, 0, sizeof(s->iommu_pcibus_by_bus_num)); > > diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c > index 1d9d01b871..7a39550cde 100644 > --- a/hw/virtio/virtio-mem.c > +++ b/hw/virtio/virtio-mem.c > @@ -738,7 +738,7 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) > vmem->bitmap = bitmap_new(vmem->bitmap_size); > > virtio_init(vdev, TYPE_VIRTIO_MEM, VIRTIO_ID_MEM, > - sizeof(struct virtio_mem_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_mem_config), VIRTQUEUE_LEGACY_MAX_SIZE); > vmem->vq = virtio_add_queue(vdev, 128, virtio_mem_handle_request); > > host_memory_backend_set_mapped(vmem->memdev, true); > diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c > index 7b3ebca178..ae0cc223e9 100644 > --- a/hw/virtio/virtio-mmio.c > +++ b/hw/virtio/virtio-mmio.c > @@ -174,7 +174,7 @@ static uint64_t virtio_mmio_read(void *opaque, hwaddr offset, unsigned size) > if (!virtio_queue_get_num(vdev, vdev->queue_sel)) { > return 0; > } > - return VIRTQUEUE_MAX_SIZE; > + return VIRTQUEUE_LEGACY_MAX_SIZE; > case VIRTIO_MMIO_QUEUE_PFN: > if (!proxy->legacy) { > qemu_log_mask(LOG_GUEST_ERROR, > @@ -348,7 +348,7 @@ static void virtio_mmio_write(void *opaque, hwaddr offset, uint64_t value, > } > break; > case VIRTIO_MMIO_QUEUE_NUM: > - trace_virtio_mmio_queue_write(value, VIRTQUEUE_MAX_SIZE); > + trace_virtio_mmio_queue_write(value, VIRTQUEUE_LEGACY_MAX_SIZE); > virtio_queue_set_num(vdev, vdev->queue_sel, value); > > if (proxy->legacy) { > diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c > index 82b54b00c5..5f4d375b58 100644 > --- a/hw/virtio/virtio-pmem.c > +++ b/hw/virtio/virtio-pmem.c > @@ -124,7 +124,7 @@ static void virtio_pmem_realize(DeviceState *dev, Error **errp) > > host_memory_backend_set_mapped(pmem->memdev, true); > virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM, > - sizeof(struct virtio_pmem_config), VIRTQUEUE_MAX_SIZE); > + sizeof(struct virtio_pmem_config), VIRTQUEUE_LEGACY_MAX_SIZE); > pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush); > } > > diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c > index 0e91d60106..ab075b22b6 100644 > --- a/hw/virtio/virtio-rng.c > +++ b/hw/virtio/virtio-rng.c > @@ -215,7 +215,8 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp) > return; > } > > - virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0, VIRTQUEUE_MAX_SIZE); > + virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0, > + VIRTQUEUE_LEGACY_MAX_SIZE); > > vrng->vq = virtio_add_queue(vdev, 8, handle_input); > vrng->quota_remaining = vrng->conf.max_bytes; > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index a37d1f7d52..fe0f13266b 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -48,7 +48,25 @@ size_t virtio_feature_get_config_size(const VirtIOFeature *features, > > typedef struct VirtQueue VirtQueue; > > -#define VIRTQUEUE_MAX_SIZE 1024 > +/* > + * This is meant as transitional measure for VIRTQUEUE_MAX_SIZE's old value > + * of 1024 to its new value of 32768. On the long-term virtio users should > + * either switch to VIRTQUEUE_MAX_SIZE, provided they support 32768, > + * otherwise they should replace this macro on their side with an > + * appropriate value actually supported by them. > + * > + * Once all virtio users switched, this macro will be removed. > + */ > +#define VIRTQUEUE_LEGACY_MAX_SIZE 1024 > + > +/* > + * Reflects the absolute theoretical maximum queue size (in amount of pages) > + * ever possible, which is actually the maximum queue size allowed by the > + * virtio protocol. This value therefore construes the maximum transfer size > + * possible with virtio (multiplied by system dependent PAGE_SIZE); assuming > + * a typical page size of 4k this would be a maximum transfer size of 128M. > + */ > +#define VIRTQUEUE_MAX_SIZE 32768 > > typedef struct VirtQueueElement > { > -- > 2.20.1