From 838bebb4c926a573839ff1bfe1b654a6ed0f9779 Mon Sep 17 00:00:00 2001 From: Feng Liu Date: Tue, 19 Dec 2023 11:32:39 +0200 Subject: [PATCH 1/9] virtio: Define feature bit for administration virtqueue Introduce VIRTIO_F_ADMIN_VQ which is used for administration virtqueue support. Signed-off-by: Feng Liu Reviewed-by: Parav Pandit Reviewed-by: Jiri Pirko Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-2-yishaih@nvidia.com Signed-off-by: Alex Williamson --- include/uapi/linux/virtio_config.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h index 8881aea60f6f..2445f365bce7 100644 --- a/include/uapi/linux/virtio_config.h +++ b/include/uapi/linux/virtio_config.h @@ -52,7 +52,7 @@ * rest are per-device feature bits. */ #define VIRTIO_TRANSPORT_F_START 28 -#define VIRTIO_TRANSPORT_F_END 41 +#define VIRTIO_TRANSPORT_F_END 42 #ifndef VIRTIO_CONFIG_NO_LEGACY /* Do we get callbacks when the ring is completely used, even if we've @@ -114,4 +114,10 @@ * This feature indicates that the driver can reset a queue individually. */ #define VIRTIO_F_RING_RESET 40 + +/* + * This feature indicates that the device support administration virtqueues. + */ +#define VIRTIO_F_ADMIN_VQ 41 + #endif /* _UAPI_LINUX_VIRTIO_CONFIG_H */ From fd27ef6b44bec26915c5b2b22c13856d9f0ba17a Mon Sep 17 00:00:00 2001 From: Feng Liu Date: Tue, 19 Dec 2023 11:32:40 +0200 Subject: [PATCH 2/9] virtio-pci: Introduce admin virtqueue Introduce support for the admin virtqueue. By negotiating VIRTIO_F_ADMIN_VQ feature, driver detects capability and creates one administration virtqueue. Administration virtqueue implementation in virtio pci generic layer, enables multiple types of upper layer drivers such as vfio, net, blk to utilize it. Signed-off-by: Feng Liu Reviewed-by: Parav Pandit Reviewed-by: Jiri Pirko Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-3-yishaih@nvidia.com Signed-off-by: Alex Williamson --- drivers/virtio/virtio.c | 37 +++++++++++-- drivers/virtio/virtio_pci_common.c | 3 ++ drivers/virtio/virtio_pci_common.h | 15 +++++- drivers/virtio/virtio_pci_modern.c | 75 +++++++++++++++++++++++++- drivers/virtio/virtio_pci_modern_dev.c | 24 ++++++++- include/linux/virtio_config.h | 4 ++ include/linux/virtio_pci_modern.h | 2 + include/uapi/linux/virtio_pci.h | 5 ++ 8 files changed, 157 insertions(+), 8 deletions(-) diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 3893dc29eb26..f4080692b351 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -302,9 +302,15 @@ static int virtio_dev_probe(struct device *_d) if (err) goto err; + if (dev->config->create_avq) { + err = dev->config->create_avq(dev); + if (err) + goto err; + } + err = drv->probe(dev); if (err) - goto err; + goto err_probe; /* If probe didn't do it, mark device DRIVER_OK ourselves. */ if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK)) @@ -316,6 +322,10 @@ static int virtio_dev_probe(struct device *_d) virtio_config_enable(dev); return 0; + +err_probe: + if (dev->config->destroy_avq) + dev->config->destroy_avq(dev); err: virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED); return err; @@ -331,6 +341,9 @@ static void virtio_dev_remove(struct device *_d) drv->remove(dev); + if (dev->config->destroy_avq) + dev->config->destroy_avq(dev); + /* Driver should have reset device. */ WARN_ON_ONCE(dev->config->get_status(dev)); @@ -489,13 +502,20 @@ EXPORT_SYMBOL_GPL(unregister_virtio_device); int virtio_device_freeze(struct virtio_device *dev) { struct virtio_driver *drv = drv_to_virtio(dev->dev.driver); + int ret; virtio_config_disable(dev); dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED; - if (drv && drv->freeze) - return drv->freeze(dev); + if (drv && drv->freeze) { + ret = drv->freeze(dev); + if (ret) + return ret; + } + + if (dev->config->destroy_avq) + dev->config->destroy_avq(dev); return 0; } @@ -532,10 +552,16 @@ int virtio_device_restore(struct virtio_device *dev) if (ret) goto err; + if (dev->config->create_avq) { + ret = dev->config->create_avq(dev); + if (ret) + goto err; + } + if (drv->restore) { ret = drv->restore(dev); if (ret) - goto err; + goto err_restore; } /* If restore didn't do it, mark device DRIVER_OK ourselves. */ @@ -546,6 +572,9 @@ int virtio_device_restore(struct virtio_device *dev) return 0; +err_restore: + if (dev->config->destroy_avq) + dev->config->destroy_avq(dev); err: virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED); return ret; diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index 7a5593997e0e..fafd13d0e4d4 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -236,6 +236,9 @@ void vp_del_vqs(struct virtio_device *vdev) int i; list_for_each_entry_safe(vq, n, &vdev->vqs, list) { + if (vp_dev->is_avq(vdev, vq->index)) + continue; + if (vp_dev->per_vq_vectors) { int v = vp_dev->vqs[vq->index]->msix_vector; diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index 4b773bd7c58c..7306128e63e9 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -41,6 +41,14 @@ struct virtio_pci_vq_info { unsigned int msix_vector; }; +struct virtio_pci_admin_vq { + /* Virtqueue info associated with this admin queue. */ + struct virtio_pci_vq_info info; + /* Name of the admin queue: avq.$vq_index. */ + char name[10]; + u16 vq_index; +}; + /* Our device structure */ struct virtio_pci_device { struct virtio_device vdev; @@ -58,9 +66,13 @@ struct virtio_pci_device { spinlock_t lock; struct list_head virtqueues; - /* array of all queues for house-keeping */ + /* Array of all virtqueues reported in the + * PCI common config num_queues field + */ struct virtio_pci_vq_info **vqs; + struct virtio_pci_admin_vq admin_vq; + /* MSI-X support */ int msix_enabled; int intx_enabled; @@ -86,6 +98,7 @@ struct virtio_pci_device { void (*del_vq)(struct virtio_pci_vq_info *info); u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector); + bool (*is_avq)(struct virtio_device *vdev, unsigned int index); }; /* Constants for MSI-X */ diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index ee6a386d250b..ce915018b5b0 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -19,6 +19,8 @@ #define VIRTIO_RING_NO_LEGACY #include "virtio_pci_common.h" +#define VIRTIO_AVQ_SGS_MAX 4 + static u64 vp_get_features(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -26,6 +28,16 @@ static u64 vp_get_features(struct virtio_device *vdev) return vp_modern_get_features(&vp_dev->mdev); } +static bool vp_is_avq(struct virtio_device *vdev, unsigned int index) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return false; + + return index == vp_dev->admin_vq.vq_index; +} + static void vp_transport_features(struct virtio_device *vdev, u64 features) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -37,6 +49,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) if (features & BIT_ULL(VIRTIO_F_RING_RESET)) __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); + + if (features & BIT_ULL(VIRTIO_F_ADMIN_VQ)) + __virtio_set_bit(vdev, VIRTIO_F_ADMIN_VQ); } static int __vp_check_common_size_one_feature(struct virtio_device *vdev, u32 fbit, @@ -69,6 +84,9 @@ static int vp_check_common_size(struct virtio_device *vdev) if (vp_check_common_size_one_feature(vdev, VIRTIO_F_RING_RESET, queue_reset)) return -EINVAL; + if (vp_check_common_size_one_feature(vdev, VIRTIO_F_ADMIN_VQ, admin_queue_num)) + return -EINVAL; + return 0; } @@ -345,6 +363,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, struct virtio_pci_modern_device *mdev = &vp_dev->mdev; bool (*notify)(struct virtqueue *vq); struct virtqueue *vq; + bool is_avq; u16 num; int err; @@ -353,11 +372,13 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, else notify = vp_notify; - if (index >= vp_modern_get_num_queues(mdev)) + is_avq = vp_is_avq(&vp_dev->vdev, index); + if (index >= vp_modern_get_num_queues(mdev) && !is_avq) return ERR_PTR(-EINVAL); + num = is_avq ? + VIRTIO_AVQ_SGS_MAX : vp_modern_get_queue_size(mdev, index); /* Check if queue is either not available or already active. */ - num = vp_modern_get_queue_size(mdev, index); if (!num || vp_modern_get_queue_enable(mdev, index)) return ERR_PTR(-ENOENT); @@ -383,6 +404,9 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, goto err; } + if (is_avq) + vp_dev->admin_vq.info.vq = vq; + return vq; err: @@ -418,6 +442,9 @@ static void del_vq(struct virtio_pci_vq_info *info) struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + if (vp_is_avq(&vp_dev->vdev, vq->index)) + vp_dev->admin_vq.info.vq = NULL; + if (vp_dev->msix_enabled) vp_modern_queue_vector(mdev, vq->index, VIRTIO_MSI_NO_VECTOR); @@ -527,6 +554,45 @@ static bool vp_get_shm_region(struct virtio_device *vdev, return true; } +static int vp_modern_create_avq(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_admin_vq *avq; + struct virtqueue *vq; + u16 admin_q_num; + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return 0; + + admin_q_num = vp_modern_avq_num(&vp_dev->mdev); + if (!admin_q_num) + return -EINVAL; + + avq = &vp_dev->admin_vq; + avq->vq_index = vp_modern_avq_index(&vp_dev->mdev); + sprintf(avq->name, "avq.%u", avq->vq_index); + vq = vp_dev->setup_vq(vp_dev, &vp_dev->admin_vq.info, avq->vq_index, NULL, + avq->name, NULL, VIRTIO_MSI_NO_VECTOR); + if (IS_ERR(vq)) { + dev_err(&vdev->dev, "failed to setup admin virtqueue, err=%ld", + PTR_ERR(vq)); + return PTR_ERR(vq); + } + + vp_modern_set_queue_enable(&vp_dev->mdev, avq->info.vq->index, true); + return 0; +} + +static void vp_modern_destroy_avq(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return; + + vp_dev->del_vq(&vp_dev->admin_vq.info); +} + static const struct virtio_config_ops virtio_pci_config_nodev_ops = { .get = NULL, .set = NULL, @@ -545,6 +611,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { .get_shm_region = vp_get_shm_region, .disable_vq_and_reset = vp_modern_disable_vq_and_reset, .enable_vq_after_reset = vp_modern_enable_vq_after_reset, + .create_avq = vp_modern_create_avq, + .destroy_avq = vp_modern_destroy_avq, }; static const struct virtio_config_ops virtio_pci_config_ops = { @@ -565,6 +633,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { .get_shm_region = vp_get_shm_region, .disable_vq_and_reset = vp_modern_disable_vq_and_reset, .enable_vq_after_reset = vp_modern_enable_vq_after_reset, + .create_avq = vp_modern_create_avq, + .destroy_avq = vp_modern_destroy_avq, }; /* the PCI probing function */ @@ -588,6 +658,7 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) vp_dev->config_vector = vp_config_vector; vp_dev->setup_vq = setup_vq; vp_dev->del_vq = del_vq; + vp_dev->is_avq = vp_is_avq; vp_dev->isr = mdev->isr; vp_dev->vdev.id = mdev->id; diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c index 7de8b1ebabac..0d3dbfaf4b23 100644 --- a/drivers/virtio/virtio_pci_modern_dev.c +++ b/drivers/virtio/virtio_pci_modern_dev.c @@ -207,6 +207,10 @@ static inline void check_offsets(void) offsetof(struct virtio_pci_modern_common_cfg, queue_notify_data)); BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_RESET != offsetof(struct virtio_pci_modern_common_cfg, queue_reset)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_IDX != + offsetof(struct virtio_pci_modern_common_cfg, admin_queue_index)); + BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_NUM != + offsetof(struct virtio_pci_modern_common_cfg, admin_queue_num)); } /* @@ -296,7 +300,7 @@ int vp_modern_probe(struct virtio_pci_modern_device *mdev) mdev->common = vp_modern_map_capability(mdev, common, sizeof(struct virtio_pci_common_cfg), 4, 0, offsetofend(struct virtio_pci_modern_common_cfg, - queue_reset), + admin_queue_num), &mdev->common_len, NULL); if (!mdev->common) goto err_map_common; @@ -719,6 +723,24 @@ void __iomem *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev, } EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify); +u16 vp_modern_avq_num(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_modern_common_cfg __iomem *cfg; + + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; + return vp_ioread16(&cfg->admin_queue_num); +} +EXPORT_SYMBOL_GPL(vp_modern_avq_num); + +u16 vp_modern_avq_index(struct virtio_pci_modern_device *mdev) +{ + struct virtio_pci_modern_common_cfg __iomem *cfg; + + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; + return vp_ioread16(&cfg->admin_queue_index); +} +EXPORT_SYMBOL_GPL(vp_modern_avq_index); + MODULE_VERSION("0.1"); MODULE_DESCRIPTION("Modern Virtio PCI Device"); MODULE_AUTHOR("Jason Wang "); diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 2b3438de2c4d..da9b271b54db 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -93,6 +93,8 @@ typedef void vq_callback_t(struct virtqueue *); * Returns 0 on success or error status * If disable_vq_and_reset is set, then enable_vq_after_reset must also be * set. + * @create_avq: create admin virtqueue resource. + * @destroy_avq: destroy admin virtqueue resource. */ struct virtio_config_ops { void (*get)(struct virtio_device *vdev, unsigned offset, @@ -120,6 +122,8 @@ struct virtio_config_ops { struct virtio_shm_region *region, u8 id); int (*disable_vq_and_reset)(struct virtqueue *vq); int (*enable_vq_after_reset)(struct virtqueue *vq); + int (*create_avq)(struct virtio_device *vdev); + void (*destroy_avq)(struct virtio_device *vdev); }; /* If driver didn't advertise the feature, it will never appear. */ diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h index a09e13a577a9..c0b1b1ca1163 100644 --- a/include/linux/virtio_pci_modern.h +++ b/include/linux/virtio_pci_modern.h @@ -125,4 +125,6 @@ int vp_modern_probe(struct virtio_pci_modern_device *mdev); void vp_modern_remove(struct virtio_pci_modern_device *mdev); int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index); void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index); +u16 vp_modern_avq_num(struct virtio_pci_modern_device *mdev); +u16 vp_modern_avq_index(struct virtio_pci_modern_device *mdev); #endif diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h index 44f4dd2add18..240ddeef7eae 100644 --- a/include/uapi/linux/virtio_pci.h +++ b/include/uapi/linux/virtio_pci.h @@ -175,6 +175,9 @@ struct virtio_pci_modern_common_cfg { __le16 queue_notify_data; /* read-write */ __le16 queue_reset; /* read-write */ + + __le16 admin_queue_index; /* read-only */ + __le16 admin_queue_num; /* read-only */ }; /* Fields in VIRTIO_PCI_CAP_PCI_CFG: */ @@ -215,6 +218,8 @@ struct virtio_pci_cfg_cap { #define VIRTIO_PCI_COMMON_Q_USEDHI 52 #define VIRTIO_PCI_COMMON_Q_NDATA 56 #define VIRTIO_PCI_COMMON_Q_RESET 58 +#define VIRTIO_PCI_COMMON_ADM_Q_IDX 60 +#define VIRTIO_PCI_COMMON_ADM_Q_NUM 62 #endif /* VIRTIO_PCI_NO_MODERN */ From 92792ac752aa80d5ee71bc291d90edd06cd76bd1 Mon Sep 17 00:00:00 2001 From: Feng Liu Date: Tue, 19 Dec 2023 11:32:41 +0200 Subject: [PATCH 3/9] virtio-pci: Introduce admin command sending function Add support for sending admin command through admin virtqueue interface. Abort any inflight admin commands once device reset completes. Activate admin queue when device becomes ready; deactivate on device reset. To comply to the below specification statement [1], the admin virtqueue is activated for upper layer users only after setting DRIVER_OK status. [1] The driver MUST NOT send any buffer available notifications to the device before setting DRIVER_OK. Signed-off-by: Feng Liu Reviewed-by: Parav Pandit Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-4-yishaih@nvidia.com Signed-off-by: Alex Williamson --- drivers/virtio/virtio_pci_common.h | 6 ++ drivers/virtio/virtio_pci_modern.c | 143 ++++++++++++++++++++++++++++- include/linux/virtio.h | 8 ++ include/uapi/linux/virtio_pci.h | 22 +++++ 4 files changed, 177 insertions(+), 2 deletions(-) diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index 7306128e63e9..282d087a9266 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -29,6 +29,7 @@ #include #include #include +#include struct virtio_pci_vq_info { /* the actual virtqueue */ @@ -44,6 +45,8 @@ struct virtio_pci_vq_info { struct virtio_pci_admin_vq { /* Virtqueue info associated with this admin queue. */ struct virtio_pci_vq_info info; + /* serializing admin commands execution and virtqueue deletion */ + struct mutex cmd_lock; /* Name of the admin queue: avq.$vq_index. */ char name[10]; u16 vq_index; @@ -152,4 +155,7 @@ static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) int virtio_pci_modern_probe(struct virtio_pci_device *); void virtio_pci_modern_remove(struct virtio_pci_device *); +int vp_modern_admin_cmd_exec(struct virtio_device *vdev, + struct virtio_admin_cmd *cmd); + #endif diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index ce915018b5b0..9bd66300a80a 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -38,6 +38,132 @@ static bool vp_is_avq(struct virtio_device *vdev, unsigned int index) return index == vp_dev->admin_vq.vq_index; } +static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq, + struct scatterlist **sgs, + unsigned int out_num, + unsigned int in_num, + void *data) +{ + struct virtqueue *vq; + int ret, len; + + vq = admin_vq->info.vq; + if (!vq) + return -EIO; + + ret = virtqueue_add_sgs(vq, sgs, out_num, in_num, data, GFP_KERNEL); + if (ret < 0) + return -EIO; + + if (unlikely(!virtqueue_kick(vq))) + return -EIO; + + while (!virtqueue_get_buf(vq, &len) && + !virtqueue_is_broken(vq)) + cpu_relax(); + + if (virtqueue_is_broken(vq)) + return -EIO; + + return 0; +} + +int vp_modern_admin_cmd_exec(struct virtio_device *vdev, + struct virtio_admin_cmd *cmd) +{ + struct scatterlist *sgs[VIRTIO_AVQ_SGS_MAX], hdr, stat; + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_admin_cmd_status *va_status; + unsigned int out_num = 0, in_num = 0; + struct virtio_admin_cmd_hdr *va_hdr; + u16 status; + int ret; + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return -EOPNOTSUPP; + + va_status = kzalloc(sizeof(*va_status), GFP_KERNEL); + if (!va_status) + return -ENOMEM; + + va_hdr = kzalloc(sizeof(*va_hdr), GFP_KERNEL); + if (!va_hdr) { + ret = -ENOMEM; + goto err_alloc; + } + + va_hdr->opcode = cmd->opcode; + va_hdr->group_type = cmd->group_type; + va_hdr->group_member_id = cmd->group_member_id; + + /* Add header */ + sg_init_one(&hdr, va_hdr, sizeof(*va_hdr)); + sgs[out_num] = &hdr; + out_num++; + + if (cmd->data_sg) { + sgs[out_num] = cmd->data_sg; + out_num++; + } + + /* Add return status */ + sg_init_one(&stat, va_status, sizeof(*va_status)); + sgs[out_num + in_num] = &stat; + in_num++; + + if (cmd->result_sg) { + sgs[out_num + in_num] = cmd->result_sg; + in_num++; + } + + mutex_lock(&vp_dev->admin_vq.cmd_lock); + ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq, sgs, + out_num, in_num, sgs); + mutex_unlock(&vp_dev->admin_vq.cmd_lock); + + if (ret) { + dev_err(&vdev->dev, + "Failed to execute command on admin vq: %d\n.", ret); + goto err_cmd_exec; + } + + status = le16_to_cpu(va_status->status); + if (status != VIRTIO_ADMIN_STATUS_OK) { + dev_err(&vdev->dev, + "admin command error: status(%#x) qualifier(%#x)\n", + status, le16_to_cpu(va_status->status_qualifier)); + ret = -status; + } + +err_cmd_exec: + kfree(va_hdr); +err_alloc: + kfree(va_status); + return ret; +} + +static void vp_modern_avq_activate(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_admin_vq *admin_vq = &vp_dev->admin_vq; + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return; + + __virtqueue_unbreak(admin_vq->info.vq); +} + +static void vp_modern_avq_deactivate(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_admin_vq *admin_vq = &vp_dev->admin_vq; + + if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ)) + return; + + __virtqueue_break(admin_vq->info.vq); +} + static void vp_transport_features(struct virtio_device *vdev, u64 features) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -213,6 +339,8 @@ static void vp_set_status(struct virtio_device *vdev, u8 status) /* We should never be setting status to 0. */ BUG_ON(status == 0); vp_modern_set_status(&vp_dev->mdev, status); + if (status & VIRTIO_CONFIG_S_DRIVER_OK) + vp_modern_avq_activate(vdev); } static void vp_reset(struct virtio_device *vdev) @@ -229,6 +357,9 @@ static void vp_reset(struct virtio_device *vdev) */ while (vp_modern_get_status(mdev)) msleep(1); + + vp_modern_avq_deactivate(vdev); + /* Flush pending VQ/configuration callbacks. */ vp_synchronize_vectors(vdev); } @@ -404,8 +535,11 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, goto err; } - if (is_avq) + if (is_avq) { + mutex_lock(&vp_dev->admin_vq.cmd_lock); vp_dev->admin_vq.info.vq = vq; + mutex_unlock(&vp_dev->admin_vq.cmd_lock); + } return vq; @@ -442,8 +576,11 @@ static void del_vq(struct virtio_pci_vq_info *info) struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); struct virtio_pci_modern_device *mdev = &vp_dev->mdev; - if (vp_is_avq(&vp_dev->vdev, vq->index)) + if (vp_is_avq(&vp_dev->vdev, vq->index)) { + mutex_lock(&vp_dev->admin_vq.cmd_lock); vp_dev->admin_vq.info.vq = NULL; + mutex_unlock(&vp_dev->admin_vq.cmd_lock); + } if (vp_dev->msix_enabled) vp_modern_queue_vector(mdev, vq->index, @@ -662,6 +799,7 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev) vp_dev->isr = mdev->isr; vp_dev->vdev.id = mdev->id; + mutex_init(&vp_dev->admin_vq.cmd_lock); return 0; } @@ -669,5 +807,6 @@ void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev) { struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + mutex_destroy(&vp_dev->admin_vq.cmd_lock); vp_modern_remove(mdev); } diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 4cc614a38376..b0201747a263 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -103,6 +103,14 @@ int virtqueue_resize(struct virtqueue *vq, u32 num, int virtqueue_reset(struct virtqueue *vq, void (*recycle)(struct virtqueue *vq, void *buf)); +struct virtio_admin_cmd { + __le16 opcode; + __le16 group_type; + __le64 group_member_id; + struct scatterlist *data_sg; + struct scatterlist *result_sg; +}; + /** * struct virtio_device - representation of a device using virtio * @index: unique position on the virtio bus diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h index 240ddeef7eae..187fd9e34a30 100644 --- a/include/uapi/linux/virtio_pci.h +++ b/include/uapi/linux/virtio_pci.h @@ -223,4 +223,26 @@ struct virtio_pci_cfg_cap { #endif /* VIRTIO_PCI_NO_MODERN */ +/* Admin command status. */ +#define VIRTIO_ADMIN_STATUS_OK 0 + +struct __packed virtio_admin_cmd_hdr { + __le16 opcode; + /* + * 1 - SR-IOV + * 2-65535 - reserved + */ + __le16 group_type; + /* Unused, reserved for future extensions. */ + __u8 reserved1[12]; + __le64 group_member_id; +}; + +struct __packed virtio_admin_cmd_status { + __le16 status; + __le16 status_qualifier; + /* Unused, reserved for future extensions. */ + __u8 reserved2[4]; +}; + #endif From 388431b9f59bbfde2b5f2fe032b0836158b09ad0 Mon Sep 17 00:00:00 2001 From: Feng Liu Date: Tue, 19 Dec 2023 11:32:42 +0200 Subject: [PATCH 4/9] virtio-pci: Introduce admin commands Introduces admin commands, as follow: The "list query" command can be used by the driver to query the set of admin commands supported by the virtio device. The "list use" command is used to inform the virtio device which admin commands the driver will use. The "legacy common cfg rd/wr" commands are used to read from/write into the legacy common configuration structure. The "legacy dev cfg rd/wr" commands are used to read from/write into the legacy device configuration structure. The "notify info" command is used to query the notification region information. Signed-off-by: Feng Liu Reviewed-by: Parav Pandit Reviewed-by: Jiri Pirko Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-5-yishaih@nvidia.com Signed-off-by: Alex Williamson --- include/uapi/linux/virtio_pci.h | 41 +++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h index 187fd9e34a30..ef3810dee7ef 100644 --- a/include/uapi/linux/virtio_pci.h +++ b/include/uapi/linux/virtio_pci.h @@ -226,6 +226,20 @@ struct virtio_pci_cfg_cap { /* Admin command status. */ #define VIRTIO_ADMIN_STATUS_OK 0 +/* Admin command opcode. */ +#define VIRTIO_ADMIN_CMD_LIST_QUERY 0x0 +#define VIRTIO_ADMIN_CMD_LIST_USE 0x1 + +/* Admin command group type. */ +#define VIRTIO_ADMIN_GROUP_TYPE_SRIOV 0x1 + +/* Transitional device admin command. */ +#define VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE 0x2 +#define VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ 0x3 +#define VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE 0x4 +#define VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ 0x5 +#define VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO 0x6 + struct __packed virtio_admin_cmd_hdr { __le16 opcode; /* @@ -245,4 +259,31 @@ struct __packed virtio_admin_cmd_status { __u8 reserved2[4]; }; +struct __packed virtio_admin_cmd_legacy_wr_data { + __u8 offset; /* Starting offset of the register(s) to write. */ + __u8 reserved[7]; + __u8 registers[]; +}; + +struct __packed virtio_admin_cmd_legacy_rd_data { + __u8 offset; /* Starting offset of the register(s) to read. */ +}; + +#define VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_END 0 +#define VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_OWNER_DEV 0x1 +#define VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_OWNER_MEM 0x2 + +#define VIRTIO_ADMIN_CMD_MAX_NOTIFY_INFO 4 + +struct __packed virtio_admin_cmd_notify_info_data { + __u8 flags; /* 0 = end of list, 1 = owner device, 2 = member device */ + __u8 bar; /* BAR of the member or the owner device */ + __u8 padding[6]; + __le64 offset; /* Offset within bar. */ +}; + +struct virtio_admin_cmd_notify_info_result { + struct virtio_admin_cmd_notify_info_data entries[VIRTIO_ADMIN_CMD_MAX_NOTIFY_INFO]; +}; + #endif From f51e146f1e5c9de02433e51f5a344556502d9c6a Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Tue, 19 Dec 2023 11:32:43 +0200 Subject: [PATCH 5/9] virtio-pci: Initialize the supported admin commands Initialize the supported admin commands upon activating the admin queue. The supported commands are saved as part of the admin queue context. Next patches in this series will expose APIs to use them. Reviewed-by: Feng Liu Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-6-yishaih@nvidia.com Signed-off-by: Alex Williamson --- drivers/virtio/Kconfig | 5 +++ drivers/virtio/virtio_pci_common.h | 19 ++++++++++++ drivers/virtio/virtio_pci_modern.c | 49 ++++++++++++++++++++++++++++-- 3 files changed, 71 insertions(+), 2 deletions(-) diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 0a53a61231c2..c17193544268 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -60,6 +60,11 @@ config VIRTIO_PCI If unsure, say M. +config VIRTIO_PCI_ADMIN_LEGACY + bool + depends on VIRTIO_PCI && (X86 || COMPILE_TEST) + default y + config VIRTIO_PCI_LEGACY bool "Support for legacy virtio draft 0.9.X and older devices" default y diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index 282d087a9266..a39bffd5fd46 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -47,6 +47,7 @@ struct virtio_pci_admin_vq { struct virtio_pci_vq_info info; /* serializing admin commands execution and virtqueue deletion */ struct mutex cmd_lock; + u64 supported_cmds; /* Name of the admin queue: avq.$vq_index. */ char name[10]; u16 vq_index; @@ -155,6 +156,24 @@ static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) int virtio_pci_modern_probe(struct virtio_pci_device *); void virtio_pci_modern_remove(struct virtio_pci_device *); +#define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \ + (BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ) | \ + BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO)) + +/* Unlike modern drivers which support hardware virtio devices, legacy drivers + * assume software-based devices: e.g. they don't use proper memory barriers + * on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more + * or less by chance. For now, only support legacy IO on X86. + */ +#ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY +#define VIRTIO_ADMIN_CMD_BITMAP VIRTIO_LEGACY_ADMIN_CMD_BITMAP +#else +#define VIRTIO_ADMIN_CMD_BITMAP 0 +#endif + int vp_modern_admin_cmd_exec(struct virtio_device *vdev, struct virtio_admin_cmd *cmd); diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 9bd66300a80a..f62b530aa3b5 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -39,6 +39,7 @@ static bool vp_is_avq(struct virtio_device *vdev, unsigned int index) } static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq, + u16 opcode, struct scatterlist **sgs, unsigned int out_num, unsigned int in_num, @@ -51,6 +52,11 @@ static int virtqueue_exec_admin_cmd(struct virtio_pci_admin_vq *admin_vq, if (!vq) return -EIO; + if (opcode != VIRTIO_ADMIN_CMD_LIST_QUERY && + opcode != VIRTIO_ADMIN_CMD_LIST_USE && + !((1ULL << opcode) & admin_vq->supported_cmds)) + return -EOPNOTSUPP; + ret = virtqueue_add_sgs(vq, sgs, out_num, in_num, data, GFP_KERNEL); if (ret < 0) return -EIO; @@ -117,8 +123,9 @@ int vp_modern_admin_cmd_exec(struct virtio_device *vdev, } mutex_lock(&vp_dev->admin_vq.cmd_lock); - ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq, sgs, - out_num, in_num, sgs); + ret = virtqueue_exec_admin_cmd(&vp_dev->admin_vq, + le16_to_cpu(cmd->opcode), + sgs, out_num, in_num, sgs); mutex_unlock(&vp_dev->admin_vq.cmd_lock); if (ret) { @@ -142,6 +149,43 @@ int vp_modern_admin_cmd_exec(struct virtio_device *vdev, return ret; } +static void virtio_pci_admin_cmd_list_init(struct virtio_device *virtio_dev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(virtio_dev); + struct virtio_admin_cmd cmd = {}; + struct scatterlist result_sg; + struct scatterlist data_sg; + __le64 *data; + int ret; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return; + + sg_init_one(&result_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_QUERY); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.result_sg = &result_sg; + + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto end; + + *data &= cpu_to_le64(VIRTIO_ADMIN_CMD_BITMAP); + sg_init_one(&data_sg, data, sizeof(*data)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LIST_USE); + cmd.data_sg = &data_sg; + cmd.result_sg = NULL; + + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (ret) + goto end; + + vp_dev->admin_vq.supported_cmds = le64_to_cpu(*data); +end: + kfree(data); +} + static void vp_modern_avq_activate(struct virtio_device *vdev) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -151,6 +195,7 @@ static void vp_modern_avq_activate(struct virtio_device *vdev) return; __virtqueue_unbreak(admin_vq->info.vq); + virtio_pci_admin_cmd_list_init(vdev); } static void vp_modern_avq_deactivate(struct virtio_device *vdev) From c3fc3e098bd64c560dde49a6e72b21b055150abe Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Tue, 19 Dec 2023 11:32:44 +0200 Subject: [PATCH 6/9] virtio-pci: Introduce APIs to execute legacy IO admin commands Introduce APIs to execute legacy IO admin commands. It includes: io_legacy_read/write for both common and the device configuration, io_legacy_notify_info. In addition, exposing an API to check whether the legacy IO commands are supported. (i.e. virtio_pci_admin_has_legacy_io()). Those APIs will be used by the next patches from this series. Note: Unlike modern drivers which support hardware virtio devices, legacy drivers assume software-based devices: e.g. they don't use proper memory barriers on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more or less by chance. For now, only support legacy IO on X86. Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-7-yishaih@nvidia.com Signed-off-by: Alex Williamson --- drivers/virtio/Makefile | 1 + drivers/virtio/virtio_pci_admin_legacy_io.c | 244 ++++++++++++++++++++ drivers/virtio/virtio_pci_common.c | 11 + drivers/virtio/virtio_pci_common.h | 2 + include/linux/virtio_pci_admin.h | 23 ++ 5 files changed, 281 insertions(+) create mode 100644 drivers/virtio/virtio_pci_admin_legacy_io.c create mode 100644 include/linux/virtio_pci_admin.h diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 8e98d24917cc..73ace62af440 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o +virtio_pci-$(CONFIG_VIRTIO_PCI_ADMIN_LEGACY) += virtio_pci_admin_legacy_io.o obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o obj-$(CONFIG_VIRTIO_VDPA) += virtio_vdpa.o diff --git a/drivers/virtio/virtio_pci_admin_legacy_io.c b/drivers/virtio/virtio_pci_admin_legacy_io.c new file mode 100644 index 000000000000..819cfbbc67c3 --- /dev/null +++ b/drivers/virtio/virtio_pci_admin_legacy_io.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved + */ + +#include +#include "virtio_pci_common.h" + +/* + * virtio_pci_admin_has_legacy_io - Checks whether the legacy IO + * commands are supported + * @dev: VF pci_dev + * + * Returns true on success. + */ +bool virtio_pci_admin_has_legacy_io(struct pci_dev *pdev) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_pci_device *vp_dev; + + if (!virtio_dev) + return false; + + if (!virtio_has_feature(virtio_dev, VIRTIO_F_ADMIN_VQ)) + return false; + + vp_dev = to_vp_device(virtio_dev); + + if ((vp_dev->admin_vq.supported_cmds & VIRTIO_LEGACY_ADMIN_CMD_BITMAP) == + VIRTIO_LEGACY_ADMIN_CMD_BITMAP) + return true; + return false; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_has_legacy_io); + +static int virtio_pci_admin_legacy_io_write(struct pci_dev *pdev, u16 opcode, + u8 offset, u8 size, u8 *buf) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_legacy_wr_data *data; + struct virtio_admin_cmd cmd = {}; + struct scatterlist data_sg; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data) + size, GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->offset = offset; + memcpy(data->registers, buf, size); + sg_init_one(&data_sg, data, sizeof(*data) + size); + cmd.opcode = cpu_to_le16(opcode); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + + kfree(data); + return ret; +} + +/* + * virtio_pci_admin_legacy_io_write_common - Write legacy common configuration + * of a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the common configuration area to write to + * @size: size of the data to write + * @buf: buffer which holds the data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_common_io_write(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_write(pdev, + VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_common_io_write); + +/* + * virtio_pci_admin_legacy_io_write_device - Write legacy device configuration + * of a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the device configuration area to write to + * @size: size of the data to write + * @buf: buffer which holds the data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_device_io_write(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_write(pdev, + VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_device_io_write); + +static int virtio_pci_admin_legacy_io_read(struct pci_dev *pdev, u16 opcode, + u8 offset, u8 size, u8 *buf) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_legacy_rd_data *data; + struct scatterlist data_sg, result_sg; + struct virtio_admin_cmd cmd = {}; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->offset = offset; + sg_init_one(&data_sg, data, sizeof(*data)); + sg_init_one(&result_sg, buf, size); + cmd.opcode = cpu_to_le16(opcode); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.data_sg = &data_sg; + cmd.result_sg = &result_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + + kfree(data); + return ret; +} + +/* + * virtio_pci_admin_legacy_device_io_read - Read legacy device configuration of + * a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the device configuration area to read from + * @size: size of the data to be read + * @buf: buffer to hold the returned data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_device_io_read(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_read(pdev, + VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_device_io_read); + +/* + * virtio_pci_admin_legacy_common_io_read - Read legacy common configuration of + * a member device + * @dev: VF pci_dev + * @offset: starting byte offset within the common configuration area to read from + * @size: size of the data to be read + * @buf: buffer to hold the returned data + * + * Note: caller must serialize access for the given device. + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_common_io_read(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf) +{ + return virtio_pci_admin_legacy_io_read(pdev, + VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ, + offset, size, buf); +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_common_io_read); + +/* + * virtio_pci_admin_legacy_io_notify_info - Read the queue notification + * information for legacy interface + * @dev: VF pci_dev + * @req_bar_flags: requested bar flags + * @bar: on output the BAR number of the owner or member device + * @bar_offset: on output the offset within bar + * + * Returns 0 on success, or negative on failure. + */ +int virtio_pci_admin_legacy_io_notify_info(struct pci_dev *pdev, + u8 req_bar_flags, u8 *bar, + u64 *bar_offset) +{ + struct virtio_device *virtio_dev = virtio_pci_vf_get_pf_dev(pdev); + struct virtio_admin_cmd_notify_info_result *result; + struct virtio_admin_cmd cmd = {}; + struct scatterlist result_sg; + int vf_id; + int ret; + + if (!virtio_dev) + return -ENODEV; + + vf_id = pci_iov_vf_id(pdev); + if (vf_id < 0) + return vf_id; + + result = kzalloc(sizeof(*result), GFP_KERNEL); + if (!result) + return -ENOMEM; + + sg_init_one(&result_sg, result, sizeof(*result)); + cmd.opcode = cpu_to_le16(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO); + cmd.group_type = cpu_to_le16(VIRTIO_ADMIN_GROUP_TYPE_SRIOV); + cmd.group_member_id = cpu_to_le64(vf_id + 1); + cmd.result_sg = &result_sg; + ret = vp_modern_admin_cmd_exec(virtio_dev, &cmd); + if (!ret) { + struct virtio_admin_cmd_notify_info_data *entry; + int i; + + ret = -ENOENT; + for (i = 0; i < VIRTIO_ADMIN_CMD_MAX_NOTIFY_INFO; i++) { + entry = &result->entries[i]; + if (entry->flags == VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_END) + break; + if (entry->flags != req_bar_flags) + continue; + *bar = entry->bar; + *bar_offset = le64_to_cpu(entry->offset); + ret = 0; + break; + } + } + + kfree(result); + return ret; +} +EXPORT_SYMBOL_GPL(virtio_pci_admin_legacy_io_notify_info); diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index fafd13d0e4d4..9f93330fc2cc 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -645,6 +645,17 @@ static struct pci_driver virtio_pci_driver = { .sriov_configure = virtio_pci_sriov_configure, }; +struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev) +{ + struct virtio_pci_device *pf_vp_dev; + + pf_vp_dev = pci_iov_get_pf_drvdata(pdev, &virtio_pci_driver); + if (IS_ERR(pf_vp_dev)) + return NULL; + + return &pf_vp_dev->vdev; +} + module_pci_driver(virtio_pci_driver); MODULE_AUTHOR("Anthony Liguori "); diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index a39bffd5fd46..7fef52bee455 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -156,6 +156,8 @@ static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) int virtio_pci_modern_probe(struct virtio_pci_device *); void virtio_pci_modern_remove(struct virtio_pci_device *); +struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev); + #define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \ (BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \ BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \ diff --git a/include/linux/virtio_pci_admin.h b/include/linux/virtio_pci_admin.h new file mode 100644 index 000000000000..f4a100a0fe2e --- /dev/null +++ b/include/linux/virtio_pci_admin.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_VIRTIO_PCI_ADMIN_H +#define _LINUX_VIRTIO_PCI_ADMIN_H + +#include +#include + +#ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY +bool virtio_pci_admin_has_legacy_io(struct pci_dev *pdev); +int virtio_pci_admin_legacy_common_io_write(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf); +int virtio_pci_admin_legacy_common_io_read(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf); +int virtio_pci_admin_legacy_device_io_write(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf); +int virtio_pci_admin_legacy_device_io_read(struct pci_dev *pdev, u8 offset, + u8 size, u8 *buf); +int virtio_pci_admin_legacy_io_notify_info(struct pci_dev *pdev, + u8 req_bar_flags, u8 *bar, + u64 *bar_offset); +#endif + +#endif /* _LINUX_VIRTIO_PCI_ADMIN_H */ From 8bccc5b80678c69f7729ce4cd232c0aa98fa6277 Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Tue, 19 Dec 2023 11:32:45 +0200 Subject: [PATCH 7/9] vfio/pci: Expose vfio_pci_core_setup_barmap() Expose vfio_pci_core_setup_barmap() to be used by drivers. This will let drivers to mmap a BAR and re-use it from both vfio and the driver when it's applicable. This API will be used in the next patches by the vfio/virtio coming driver. Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Yishai Hadas Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/r/20231219093247.170936-8-yishaih@nvidia.com Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_rdwr.c | 7 ++++--- include/linux/vfio_pci_core.h | 1 + 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c index e27de61ac9fe..a9887fd6de46 100644 --- a/drivers/vfio/pci/vfio_pci_rdwr.c +++ b/drivers/vfio/pci/vfio_pci_rdwr.c @@ -200,7 +200,7 @@ static ssize_t do_io_rw(struct vfio_pci_core_device *vdev, bool test_mem, return done; } -static int vfio_pci_setup_barmap(struct vfio_pci_core_device *vdev, int bar) +int vfio_pci_core_setup_barmap(struct vfio_pci_core_device *vdev, int bar) { struct pci_dev *pdev = vdev->pdev; int ret; @@ -223,6 +223,7 @@ static int vfio_pci_setup_barmap(struct vfio_pci_core_device *vdev, int bar) return 0; } +EXPORT_SYMBOL_GPL(vfio_pci_core_setup_barmap); ssize_t vfio_pci_bar_rw(struct vfio_pci_core_device *vdev, char __user *buf, size_t count, loff_t *ppos, bool iswrite) @@ -262,7 +263,7 @@ ssize_t vfio_pci_bar_rw(struct vfio_pci_core_device *vdev, char __user *buf, } x_end = end; } else { - int ret = vfio_pci_setup_barmap(vdev, bar); + int ret = vfio_pci_core_setup_barmap(vdev, bar); if (ret) { done = ret; goto out; @@ -438,7 +439,7 @@ int vfio_pci_ioeventfd(struct vfio_pci_core_device *vdev, loff_t offset, return -EINVAL; #endif - ret = vfio_pci_setup_barmap(vdev, bar); + ret = vfio_pci_core_setup_barmap(vdev, bar); if (ret) return ret; diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h index 562e8754869d..67ac58e20e1d 100644 --- a/include/linux/vfio_pci_core.h +++ b/include/linux/vfio_pci_core.h @@ -127,6 +127,7 @@ int vfio_pci_core_match(struct vfio_device *core_vdev, char *buf); int vfio_pci_core_enable(struct vfio_pci_core_device *vdev); void vfio_pci_core_disable(struct vfio_pci_core_device *vdev); void vfio_pci_core_finish_enable(struct vfio_pci_core_device *vdev); +int vfio_pci_core_setup_barmap(struct vfio_pci_core_device *vdev, int bar); pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev, pci_channel_state_t state); From 8486ae162b3b6cc1055366f044495cf1966231f1 Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Tue, 19 Dec 2023 11:32:46 +0200 Subject: [PATCH 8/9] vfio/pci: Expose vfio_pci_core_iowrite/read##size() Expose vfio_pci_core_iowrite/read##size() to let it be used by drivers. This functionality is needed to enable direct access to some physical BAR of the device with the proper locks/checks in place. The next patches from this series will use this functionality on a data path flow when a direct access to the BAR is needed. Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Yishai Hadas Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/r/20231219093247.170936-9-yishaih@nvidia.com Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_rdwr.c | 50 +++++++++++++++++--------------- include/linux/vfio_pci_core.h | 19 ++++++++++++ 2 files changed, 45 insertions(+), 24 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c index a9887fd6de46..07fea08ea8a2 100644 --- a/drivers/vfio/pci/vfio_pci_rdwr.c +++ b/drivers/vfio/pci/vfio_pci_rdwr.c @@ -38,7 +38,7 @@ #define vfio_iowrite8 iowrite8 #define VFIO_IOWRITE(size) \ -static int vfio_pci_iowrite##size(struct vfio_pci_core_device *vdev, \ +int vfio_pci_core_iowrite##size(struct vfio_pci_core_device *vdev, \ bool test_mem, u##size val, void __iomem *io) \ { \ if (test_mem) { \ @@ -55,7 +55,8 @@ static int vfio_pci_iowrite##size(struct vfio_pci_core_device *vdev, \ up_read(&vdev->memory_lock); \ \ return 0; \ -} +} \ +EXPORT_SYMBOL_GPL(vfio_pci_core_iowrite##size); VFIO_IOWRITE(8) VFIO_IOWRITE(16) @@ -65,7 +66,7 @@ VFIO_IOWRITE(64) #endif #define VFIO_IOREAD(size) \ -static int vfio_pci_ioread##size(struct vfio_pci_core_device *vdev, \ +int vfio_pci_core_ioread##size(struct vfio_pci_core_device *vdev, \ bool test_mem, u##size *val, void __iomem *io) \ { \ if (test_mem) { \ @@ -82,7 +83,8 @@ static int vfio_pci_ioread##size(struct vfio_pci_core_device *vdev, \ up_read(&vdev->memory_lock); \ \ return 0; \ -} +} \ +EXPORT_SYMBOL_GPL(vfio_pci_core_ioread##size); VFIO_IOREAD(8) VFIO_IOREAD(16) @@ -119,13 +121,13 @@ static ssize_t do_io_rw(struct vfio_pci_core_device *vdev, bool test_mem, if (copy_from_user(&val, buf, 4)) return -EFAULT; - ret = vfio_pci_iowrite32(vdev, test_mem, - val, io + off); + ret = vfio_pci_core_iowrite32(vdev, test_mem, + val, io + off); if (ret) return ret; } else { - ret = vfio_pci_ioread32(vdev, test_mem, - &val, io + off); + ret = vfio_pci_core_ioread32(vdev, test_mem, + &val, io + off); if (ret) return ret; @@ -141,13 +143,13 @@ static ssize_t do_io_rw(struct vfio_pci_core_device *vdev, bool test_mem, if (copy_from_user(&val, buf, 2)) return -EFAULT; - ret = vfio_pci_iowrite16(vdev, test_mem, - val, io + off); + ret = vfio_pci_core_iowrite16(vdev, test_mem, + val, io + off); if (ret) return ret; } else { - ret = vfio_pci_ioread16(vdev, test_mem, - &val, io + off); + ret = vfio_pci_core_ioread16(vdev, test_mem, + &val, io + off); if (ret) return ret; @@ -163,13 +165,13 @@ static ssize_t do_io_rw(struct vfio_pci_core_device *vdev, bool test_mem, if (copy_from_user(&val, buf, 1)) return -EFAULT; - ret = vfio_pci_iowrite8(vdev, test_mem, - val, io + off); + ret = vfio_pci_core_iowrite8(vdev, test_mem, + val, io + off); if (ret) return ret; } else { - ret = vfio_pci_ioread8(vdev, test_mem, - &val, io + off); + ret = vfio_pci_core_ioread8(vdev, test_mem, + &val, io + off); if (ret) return ret; @@ -364,21 +366,21 @@ static void vfio_pci_ioeventfd_do_write(struct vfio_pci_ioeventfd *ioeventfd, { switch (ioeventfd->count) { case 1: - vfio_pci_iowrite8(ioeventfd->vdev, test_mem, - ioeventfd->data, ioeventfd->addr); + vfio_pci_core_iowrite8(ioeventfd->vdev, test_mem, + ioeventfd->data, ioeventfd->addr); break; case 2: - vfio_pci_iowrite16(ioeventfd->vdev, test_mem, - ioeventfd->data, ioeventfd->addr); + vfio_pci_core_iowrite16(ioeventfd->vdev, test_mem, + ioeventfd->data, ioeventfd->addr); break; case 4: - vfio_pci_iowrite32(ioeventfd->vdev, test_mem, - ioeventfd->data, ioeventfd->addr); + vfio_pci_core_iowrite32(ioeventfd->vdev, test_mem, + ioeventfd->data, ioeventfd->addr); break; #ifdef iowrite64 case 8: - vfio_pci_iowrite64(ioeventfd->vdev, test_mem, - ioeventfd->data, ioeventfd->addr); + vfio_pci_core_iowrite64(ioeventfd->vdev, test_mem, + ioeventfd->data, ioeventfd->addr); break; #endif } diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h index 67ac58e20e1d..85e84b92751b 100644 --- a/include/linux/vfio_pci_core.h +++ b/include/linux/vfio_pci_core.h @@ -131,4 +131,23 @@ int vfio_pci_core_setup_barmap(struct vfio_pci_core_device *vdev, int bar); pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev, pci_channel_state_t state); +#define VFIO_IOWRITE_DECLATION(size) \ +int vfio_pci_core_iowrite##size(struct vfio_pci_core_device *vdev, \ + bool test_mem, u##size val, void __iomem *io); + +VFIO_IOWRITE_DECLATION(8) +VFIO_IOWRITE_DECLATION(16) +VFIO_IOWRITE_DECLATION(32) +#ifdef iowrite64 +VFIO_IOWRITE_DECLATION(64) +#endif + +#define VFIO_IOREAD_DECLATION(size) \ +int vfio_pci_core_ioread##size(struct vfio_pci_core_device *vdev, \ + bool test_mem, u##size *val, void __iomem *io); + +VFIO_IOREAD_DECLATION(8) +VFIO_IOREAD_DECLATION(16) +VFIO_IOREAD_DECLATION(32) + #endif /* VFIO_PCI_CORE_H */ From eb61eca0e8c3efbdd6d3c9d2b7f70bf67e165f7d Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Tue, 19 Dec 2023 11:32:47 +0200 Subject: [PATCH 9/9] vfio/virtio: Introduce a vfio driver over virtio devices Introduce a vfio driver over virtio devices to support the legacy interface functionality for VFs. Background, from the virtio spec [1]. -------------------------------------------------------------------- In some systems, there is a need to support a virtio legacy driver with a device that does not directly support the legacy interface. In such scenarios, a group owner device can provide the legacy interface functionality for the group member devices. The driver of the owner device can then access the legacy interface of a member device on behalf of the legacy member device driver. For example, with the SR-IOV group type, group members (VFs) can not present the legacy interface in an I/O BAR in BAR0 as expected by the legacy pci driver. If the legacy driver is running inside a virtual machine, the hypervisor executing the virtual machine can present a virtual device with an I/O BAR in BAR0. The hypervisor intercepts the legacy driver accesses to this I/O BAR and forwards them to the group owner device (PF) using group administration commands. -------------------------------------------------------------------- Specifically, this driver adds support for a virtio-net VF to be exposed as a transitional device to a guest driver and allows the legacy IO BAR functionality on top. This allows a VM which uses a legacy virtio-net driver in the guest to work transparently over a VF which its driver in the host is that new driver. The driver can be extended easily to support some other types of virtio devices (e.g virtio-blk), by adding in a few places the specific type properties as was done for virtio-net. For now, only the virtio-net use case was tested and as such we introduce the support only for such a device. Practically, Upon probing a VF for a virtio-net device, in case its PF supports legacy access over the virtio admin commands and the VF doesn't have BAR 0, we set some specific 'vfio_device_ops' to be able to simulate in SW a transitional device with I/O BAR in BAR 0. The existence of the simulated I/O bar is reported later on by overwriting the VFIO_DEVICE_GET_REGION_INFO command and the device exposes itself as a transitional device by overwriting some properties upon reading its config space. Once we report the existence of I/O BAR as BAR 0 a legacy driver in the guest may use it via read/write calls according to the virtio specification. Any read/write towards the control parts of the BAR will be captured by the new driver and will be translated into admin commands towards the device. In addition, any data path read/write access (i.e. virtio driver notifications) will be captured by the driver and forwarded to the physical BAR which its properties were supplied by the admin command VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO upon the probing/init flow. With that code in place a legacy driver in the guest has the look and feel as if having a transitional device with legacy support for both its control and data path flows. [1] https://github.com/oasis-tcs/virtio-spec/commit/03c2d32e5093ca9f2a17797242fbef88efe94b8c Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Yishai Hadas Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/r/20231219093247.170936-10-yishaih@nvidia.com Signed-off-by: Alex Williamson --- MAINTAINERS | 7 + drivers/vfio/pci/Kconfig | 2 + drivers/vfio/pci/Makefile | 2 + drivers/vfio/pci/virtio/Kconfig | 15 + drivers/vfio/pci/virtio/Makefile | 3 + drivers/vfio/pci/virtio/main.c | 576 +++++++++++++++++++++++++++++++ 6 files changed, 605 insertions(+) create mode 100644 drivers/vfio/pci/virtio/Kconfig create mode 100644 drivers/vfio/pci/virtio/Makefile create mode 100644 drivers/vfio/pci/virtio/main.c diff --git a/MAINTAINERS b/MAINTAINERS index 788be9ab5b73..c4cb7df15cd9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -22872,6 +22872,13 @@ L: kvm@vger.kernel.org S: Maintained F: drivers/vfio/pci/mlx5/ +VFIO VIRTIO PCI DRIVER +M: Yishai Hadas +L: kvm@vger.kernel.org +L: virtualization@lists.linux-foundation.org +S: Maintained +F: drivers/vfio/pci/virtio + VFIO PCI DEVICE SPECIFIC DRIVERS R: Jason Gunthorpe R: Yishai Hadas diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig index 8125e5f37832..18c397df566d 100644 --- a/drivers/vfio/pci/Kconfig +++ b/drivers/vfio/pci/Kconfig @@ -65,4 +65,6 @@ source "drivers/vfio/pci/hisilicon/Kconfig" source "drivers/vfio/pci/pds/Kconfig" +source "drivers/vfio/pci/virtio/Kconfig" + endmenu diff --git a/drivers/vfio/pci/Makefile b/drivers/vfio/pci/Makefile index 45167be462d8..046139a4eca5 100644 --- a/drivers/vfio/pci/Makefile +++ b/drivers/vfio/pci/Makefile @@ -13,3 +13,5 @@ obj-$(CONFIG_MLX5_VFIO_PCI) += mlx5/ obj-$(CONFIG_HISI_ACC_VFIO_PCI) += hisilicon/ obj-$(CONFIG_PDS_VFIO_PCI) += pds/ + +obj-$(CONFIG_VIRTIO_VFIO_PCI) += virtio/ diff --git a/drivers/vfio/pci/virtio/Kconfig b/drivers/vfio/pci/virtio/Kconfig new file mode 100644 index 000000000000..fc3a0be9d8d4 --- /dev/null +++ b/drivers/vfio/pci/virtio/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0-only +config VIRTIO_VFIO_PCI + tristate "VFIO support for VIRTIO NET PCI devices" + depends on VIRTIO_PCI_ADMIN_LEGACY + select VFIO_PCI_CORE + help + This provides support for exposing VIRTIO NET VF devices which support + legacy IO access, using the VFIO framework that can work with a legacy + virtio driver in the guest. + Based on PCIe spec, VFs do not support I/O Space. + As of that this driver emulates I/O BAR in software to let a VF be + seen as a transitional device by its users and let it work with + a legacy driver. + + If you don't know what to do here, say N. diff --git a/drivers/vfio/pci/virtio/Makefile b/drivers/vfio/pci/virtio/Makefile new file mode 100644 index 000000000000..7171105baf33 --- /dev/null +++ b/drivers/vfio/pci/virtio/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_VIRTIO_VFIO_PCI) += virtio-vfio-pci.o +virtio-vfio-pci-y := main.o diff --git a/drivers/vfio/pci/virtio/main.c b/drivers/vfio/pci/virtio/main.c new file mode 100644 index 000000000000..291c55b641f1 --- /dev/null +++ b/drivers/vfio/pci/virtio/main.c @@ -0,0 +1,576 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct virtiovf_pci_core_device { + struct vfio_pci_core_device core_device; + u8 *bar0_virtual_buf; + /* synchronize access to the virtual buf */ + struct mutex bar_mutex; + void __iomem *notify_addr; + u64 notify_offset; + __le32 pci_base_addr_0; + __le16 pci_cmd; + u8 bar0_virtual_buf_size; + u8 notify_bar; +}; + +static int +virtiovf_issue_legacy_rw_cmd(struct virtiovf_pci_core_device *virtvdev, + loff_t pos, char __user *buf, + size_t count, bool read) +{ + bool msix_enabled = + (virtvdev->core_device.irq_type == VFIO_PCI_MSIX_IRQ_INDEX); + struct pci_dev *pdev = virtvdev->core_device.pdev; + u8 *bar0_buf = virtvdev->bar0_virtual_buf; + bool common; + u8 offset; + int ret; + + common = pos < VIRTIO_PCI_CONFIG_OFF(msix_enabled); + /* offset within the relevant configuration area */ + offset = common ? pos : pos - VIRTIO_PCI_CONFIG_OFF(msix_enabled); + mutex_lock(&virtvdev->bar_mutex); + if (read) { + if (common) + ret = virtio_pci_admin_legacy_common_io_read(pdev, offset, + count, bar0_buf + pos); + else + ret = virtio_pci_admin_legacy_device_io_read(pdev, offset, + count, bar0_buf + pos); + if (ret) + goto out; + if (copy_to_user(buf, bar0_buf + pos, count)) + ret = -EFAULT; + } else { + if (copy_from_user(bar0_buf + pos, buf, count)) { + ret = -EFAULT; + goto out; + } + + if (common) + ret = virtio_pci_admin_legacy_common_io_write(pdev, offset, + count, bar0_buf + pos); + else + ret = virtio_pci_admin_legacy_device_io_write(pdev, offset, + count, bar0_buf + pos); + } +out: + mutex_unlock(&virtvdev->bar_mutex); + return ret; +} + +static int +virtiovf_pci_bar0_rw(struct virtiovf_pci_core_device *virtvdev, + loff_t pos, char __user *buf, + size_t count, bool read) +{ + struct vfio_pci_core_device *core_device = &virtvdev->core_device; + struct pci_dev *pdev = core_device->pdev; + u16 queue_notify; + int ret; + + if (!(le16_to_cpu(virtvdev->pci_cmd) & PCI_COMMAND_IO)) + return -EIO; + + if (pos + count > virtvdev->bar0_virtual_buf_size) + return -EINVAL; + + ret = pm_runtime_resume_and_get(&pdev->dev); + if (ret) { + pci_info_ratelimited(pdev, "runtime resume failed %d\n", ret); + return -EIO; + } + + switch (pos) { + case VIRTIO_PCI_QUEUE_NOTIFY: + if (count != sizeof(queue_notify)) { + ret = -EINVAL; + goto end; + } + if (read) { + ret = vfio_pci_core_ioread16(core_device, true, &queue_notify, + virtvdev->notify_addr); + if (ret) + goto end; + if (copy_to_user(buf, &queue_notify, + sizeof(queue_notify))) { + ret = -EFAULT; + goto end; + } + } else { + if (copy_from_user(&queue_notify, buf, count)) { + ret = -EFAULT; + goto end; + } + ret = vfio_pci_core_iowrite16(core_device, true, queue_notify, + virtvdev->notify_addr); + } + break; + default: + ret = virtiovf_issue_legacy_rw_cmd(virtvdev, pos, buf, count, + read); + } + +end: + pm_runtime_put(&pdev->dev); + return ret ? ret : count; +} + +static bool range_intersect_range(loff_t range1_start, size_t count1, + loff_t range2_start, size_t count2, + loff_t *start_offset, + size_t *intersect_count, + size_t *register_offset) +{ + if (range1_start <= range2_start && + range1_start + count1 > range2_start) { + *start_offset = range2_start - range1_start; + *intersect_count = min_t(size_t, count2, + range1_start + count1 - range2_start); + *register_offset = 0; + return true; + } + + if (range1_start > range2_start && + range1_start < range2_start + count2) { + *start_offset = 0; + *intersect_count = min_t(size_t, count1, + range2_start + count2 - range1_start); + *register_offset = range1_start - range2_start; + return true; + } + + return false; +} + +static ssize_t virtiovf_pci_read_config(struct vfio_device *core_vdev, + char __user *buf, size_t count, + loff_t *ppos) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + size_t register_offset; + loff_t copy_offset; + size_t copy_count; + __le32 val32; + __le16 val16; + u8 val8; + int ret; + + ret = vfio_pci_core_read(core_vdev, buf, count, ppos); + if (ret < 0) + return ret; + + if (range_intersect_range(pos, count, PCI_DEVICE_ID, sizeof(val16), + ©_offset, ©_count, ®ister_offset)) { + val16 = cpu_to_le16(VIRTIO_TRANS_ID_NET); + if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, copy_count)) + return -EFAULT; + } + + if ((le16_to_cpu(virtvdev->pci_cmd) & PCI_COMMAND_IO) && + range_intersect_range(pos, count, PCI_COMMAND, sizeof(val16), + ©_offset, ©_count, ®ister_offset)) { + if (copy_from_user((void *)&val16 + register_offset, buf + copy_offset, + copy_count)) + return -EFAULT; + val16 |= cpu_to_le16(PCI_COMMAND_IO); + if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, + copy_count)) + return -EFAULT; + } + + if (range_intersect_range(pos, count, PCI_REVISION_ID, sizeof(val8), + ©_offset, ©_count, ®ister_offset)) { + /* Transional needs to have revision 0 */ + val8 = 0; + if (copy_to_user(buf + copy_offset, &val8, copy_count)) + return -EFAULT; + } + + if (range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, sizeof(val32), + ©_offset, ©_count, ®ister_offset)) { + u32 bar_mask = ~(virtvdev->bar0_virtual_buf_size - 1); + u32 pci_base_addr_0 = le32_to_cpu(virtvdev->pci_base_addr_0); + + val32 = cpu_to_le32((pci_base_addr_0 & bar_mask) | PCI_BASE_ADDRESS_SPACE_IO); + if (copy_to_user(buf + copy_offset, (void *)&val32 + register_offset, copy_count)) + return -EFAULT; + } + + if (range_intersect_range(pos, count, PCI_SUBSYSTEM_ID, sizeof(val16), + ©_offset, ©_count, ®ister_offset)) { + /* + * Transitional devices use the PCI subsystem device id as + * virtio device id, same as legacy driver always did. + */ + val16 = cpu_to_le16(VIRTIO_ID_NET); + if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, + copy_count)) + return -EFAULT; + } + + if (range_intersect_range(pos, count, PCI_SUBSYSTEM_VENDOR_ID, sizeof(val16), + ©_offset, ©_count, ®ister_offset)) { + val16 = cpu_to_le16(PCI_VENDOR_ID_REDHAT_QUMRANET); + if (copy_to_user(buf + copy_offset, (void *)&val16 + register_offset, + copy_count)) + return -EFAULT; + } + + return count; +} + +static ssize_t +virtiovf_pci_core_read(struct vfio_device *core_vdev, char __user *buf, + size_t count, loff_t *ppos) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + + if (!count) + return 0; + + if (index == VFIO_PCI_CONFIG_REGION_INDEX) + return virtiovf_pci_read_config(core_vdev, buf, count, ppos); + + if (index == VFIO_PCI_BAR0_REGION_INDEX) + return virtiovf_pci_bar0_rw(virtvdev, pos, buf, count, true); + + return vfio_pci_core_read(core_vdev, buf, count, ppos); +} + +static ssize_t virtiovf_pci_write_config(struct vfio_device *core_vdev, + const char __user *buf, size_t count, + loff_t *ppos) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + size_t register_offset; + loff_t copy_offset; + size_t copy_count; + + if (range_intersect_range(pos, count, PCI_COMMAND, sizeof(virtvdev->pci_cmd), + ©_offset, ©_count, + ®ister_offset)) { + if (copy_from_user((void *)&virtvdev->pci_cmd + register_offset, + buf + copy_offset, + copy_count)) + return -EFAULT; + } + + if (range_intersect_range(pos, count, PCI_BASE_ADDRESS_0, + sizeof(virtvdev->pci_base_addr_0), + ©_offset, ©_count, + ®ister_offset)) { + if (copy_from_user((void *)&virtvdev->pci_base_addr_0 + register_offset, + buf + copy_offset, + copy_count)) + return -EFAULT; + } + + return vfio_pci_core_write(core_vdev, buf, count, ppos); +} + +static ssize_t +virtiovf_pci_core_write(struct vfio_device *core_vdev, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + + if (!count) + return 0; + + if (index == VFIO_PCI_CONFIG_REGION_INDEX) + return virtiovf_pci_write_config(core_vdev, buf, count, ppos); + + if (index == VFIO_PCI_BAR0_REGION_INDEX) + return virtiovf_pci_bar0_rw(virtvdev, pos, (char __user *)buf, count, false); + + return vfio_pci_core_write(core_vdev, buf, count, ppos); +} + +static int +virtiovf_pci_ioctl_get_region_info(struct vfio_device *core_vdev, + unsigned int cmd, unsigned long arg) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + unsigned long minsz = offsetofend(struct vfio_region_info, offset); + void __user *uarg = (void __user *)arg; + struct vfio_region_info info = {}; + + if (copy_from_user(&info, uarg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + switch (info.index) { + case VFIO_PCI_BAR0_REGION_INDEX: + info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); + info.size = virtvdev->bar0_virtual_buf_size; + info.flags = VFIO_REGION_INFO_FLAG_READ | + VFIO_REGION_INFO_FLAG_WRITE; + return copy_to_user(uarg, &info, minsz) ? -EFAULT : 0; + default: + return vfio_pci_core_ioctl(core_vdev, cmd, arg); + } +} + +static long +virtiovf_vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd, + unsigned long arg) +{ + switch (cmd) { + case VFIO_DEVICE_GET_REGION_INFO: + return virtiovf_pci_ioctl_get_region_info(core_vdev, cmd, arg); + default: + return vfio_pci_core_ioctl(core_vdev, cmd, arg); + } +} + +static int +virtiovf_set_notify_addr(struct virtiovf_pci_core_device *virtvdev) +{ + struct vfio_pci_core_device *core_device = &virtvdev->core_device; + int ret; + + /* + * Setup the BAR where the 'notify' exists to be used by vfio as well + * This will let us mmap it only once and use it when needed. + */ + ret = vfio_pci_core_setup_barmap(core_device, + virtvdev->notify_bar); + if (ret) + return ret; + + virtvdev->notify_addr = core_device->barmap[virtvdev->notify_bar] + + virtvdev->notify_offset; + return 0; +} + +static int virtiovf_pci_open_device(struct vfio_device *core_vdev) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + struct vfio_pci_core_device *vdev = &virtvdev->core_device; + int ret; + + ret = vfio_pci_core_enable(vdev); + if (ret) + return ret; + + if (virtvdev->bar0_virtual_buf) { + /* + * Upon close_device() the vfio_pci_core_disable() is called + * and will close all the previous mmaps, so it seems that the + * valid life cycle for the 'notify' addr is per open/close. + */ + ret = virtiovf_set_notify_addr(virtvdev); + if (ret) { + vfio_pci_core_disable(vdev); + return ret; + } + } + + vfio_pci_core_finish_enable(vdev); + return 0; +} + +static int virtiovf_get_device_config_size(unsigned short device) +{ + /* Network card */ + return offsetofend(struct virtio_net_config, status); +} + +static int virtiovf_read_notify_info(struct virtiovf_pci_core_device *virtvdev) +{ + u64 offset; + int ret; + u8 bar; + + ret = virtio_pci_admin_legacy_io_notify_info(virtvdev->core_device.pdev, + VIRTIO_ADMIN_CMD_NOTIFY_INFO_FLAGS_OWNER_MEM, + &bar, &offset); + if (ret) + return ret; + + virtvdev->notify_bar = bar; + virtvdev->notify_offset = offset; + return 0; +} + +static int virtiovf_pci_init_device(struct vfio_device *core_vdev) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + struct pci_dev *pdev; + int ret; + + ret = vfio_pci_core_init_dev(core_vdev); + if (ret) + return ret; + + pdev = virtvdev->core_device.pdev; + ret = virtiovf_read_notify_info(virtvdev); + if (ret) + return ret; + + virtvdev->bar0_virtual_buf_size = VIRTIO_PCI_CONFIG_OFF(true) + + virtiovf_get_device_config_size(pdev->device); + BUILD_BUG_ON(!is_power_of_2(virtvdev->bar0_virtual_buf_size)); + virtvdev->bar0_virtual_buf = kzalloc(virtvdev->bar0_virtual_buf_size, + GFP_KERNEL); + if (!virtvdev->bar0_virtual_buf) + return -ENOMEM; + mutex_init(&virtvdev->bar_mutex); + return 0; +} + +static void virtiovf_pci_core_release_dev(struct vfio_device *core_vdev) +{ + struct virtiovf_pci_core_device *virtvdev = container_of( + core_vdev, struct virtiovf_pci_core_device, core_device.vdev); + + kfree(virtvdev->bar0_virtual_buf); + vfio_pci_core_release_dev(core_vdev); +} + +static const struct vfio_device_ops virtiovf_vfio_pci_tran_ops = { + .name = "virtio-vfio-pci-trans", + .init = virtiovf_pci_init_device, + .release = virtiovf_pci_core_release_dev, + .open_device = virtiovf_pci_open_device, + .close_device = vfio_pci_core_close_device, + .ioctl = virtiovf_vfio_pci_core_ioctl, + .device_feature = vfio_pci_core_ioctl_feature, + .read = virtiovf_pci_core_read, + .write = virtiovf_pci_core_write, + .mmap = vfio_pci_core_mmap, + .request = vfio_pci_core_request, + .match = vfio_pci_core_match, + .bind_iommufd = vfio_iommufd_physical_bind, + .unbind_iommufd = vfio_iommufd_physical_unbind, + .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, +}; + +static const struct vfio_device_ops virtiovf_vfio_pci_ops = { + .name = "virtio-vfio-pci", + .init = vfio_pci_core_init_dev, + .release = vfio_pci_core_release_dev, + .open_device = virtiovf_pci_open_device, + .close_device = vfio_pci_core_close_device, + .ioctl = vfio_pci_core_ioctl, + .device_feature = vfio_pci_core_ioctl_feature, + .read = vfio_pci_core_read, + .write = vfio_pci_core_write, + .mmap = vfio_pci_core_mmap, + .request = vfio_pci_core_request, + .match = vfio_pci_core_match, + .bind_iommufd = vfio_iommufd_physical_bind, + .unbind_iommufd = vfio_iommufd_physical_unbind, + .attach_ioas = vfio_iommufd_physical_attach_ioas, + .detach_ioas = vfio_iommufd_physical_detach_ioas, +}; + +static bool virtiovf_bar0_exists(struct pci_dev *pdev) +{ + struct resource *res = pdev->resource; + + return res->flags; +} + +static int virtiovf_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + const struct vfio_device_ops *ops = &virtiovf_vfio_pci_ops; + struct virtiovf_pci_core_device *virtvdev; + int ret; + + if (pdev->is_virtfn && virtio_pci_admin_has_legacy_io(pdev) && + !virtiovf_bar0_exists(pdev)) + ops = &virtiovf_vfio_pci_tran_ops; + + virtvdev = vfio_alloc_device(virtiovf_pci_core_device, core_device.vdev, + &pdev->dev, ops); + if (IS_ERR(virtvdev)) + return PTR_ERR(virtvdev); + + dev_set_drvdata(&pdev->dev, &virtvdev->core_device); + ret = vfio_pci_core_register_device(&virtvdev->core_device); + if (ret) + goto out; + return 0; +out: + vfio_put_device(&virtvdev->core_device.vdev); + return ret; +} + +static void virtiovf_pci_remove(struct pci_dev *pdev) +{ + struct virtiovf_pci_core_device *virtvdev = dev_get_drvdata(&pdev->dev); + + vfio_pci_core_unregister_device(&virtvdev->core_device); + vfio_put_device(&virtvdev->core_device.vdev); +} + +static const struct pci_device_id virtiovf_pci_table[] = { + /* Only virtio-net is supported/tested so far */ + { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_REDHAT_QUMRANET, 0x1041) }, + {} +}; + +MODULE_DEVICE_TABLE(pci, virtiovf_pci_table); + +void virtiovf_pci_aer_reset_done(struct pci_dev *pdev) +{ + struct virtiovf_pci_core_device *virtvdev = dev_get_drvdata(&pdev->dev); + + virtvdev->pci_cmd = 0; +} + +static const struct pci_error_handlers virtiovf_err_handlers = { + .reset_done = virtiovf_pci_aer_reset_done, + .error_detected = vfio_pci_core_aer_err_detected, +}; + +static struct pci_driver virtiovf_pci_driver = { + .name = KBUILD_MODNAME, + .id_table = virtiovf_pci_table, + .probe = virtiovf_pci_probe, + .remove = virtiovf_pci_remove, + .err_handler = &virtiovf_err_handlers, + .driver_managed_dma = true, +}; + +module_pci_driver(virtiovf_pci_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Yishai Hadas "); +MODULE_DESCRIPTION( + "VIRTIO VFIO PCI - User Level meta-driver for VIRTIO NET devices");