From: Feng Liu <feliu@xxxxxxxxxx> 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 <feliu@xxxxxxxxxx> Reviewed-by: Parav Pandit <parav@xxxxxxxxxx> Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: Yishai Hadas <yishaih@xxxxxxxxxx> --- 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 <linux/virtio_pci_modern.h> #include <linux/highmem.h> #include <linux/spinlock.h> +#include <linux/mutex.h> 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 -- 2.27.0