[RFC 3/7] vhost: Add 3 new uapi to support iommufd
From: Cindy Lu <hidden>
Date: 2023-09-23 17:07:21
Also in:
lkml
Subsystem:
the rest, virtio host (vhost) · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
VHOST_VDPA_SET_IOMMU_FD: bind the device to iommufd device VDPA_DEVICE_ATTACH_IOMMUFD_AS: Attach a vdpa device to an iommufd address space specified by IOAS id. VDPA_DEVICE_DETACH_IOMMUFD_AS: Detach a vdpa device from the iommufd address space Signed-off-by: Cindy Lu <redacted> --- drivers/vhost/vdpa.c | 191 +++++++++++++++++++++++++++++++++++++ include/uapi/linux/vhost.h | 71 ++++++++++++++ 2 files changed, 262 insertions(+)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index ec32f785dfde..91da012084e9 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c@@ -18,6 +18,7 @@ #include <linux/mm.h> #include <linux/slab.h> #include <linux/iommu.h> +#include <linux/iommufd.h> #include <linux/uuid.h> #include <linux/vdpa.h> #include <linux/nospec.h>
@@ -25,6 +26,8 @@ #include "vhost.h" +MODULE_IMPORT_NS(IOMMUFD); + enum { VHOST_VDPA_BACKEND_FEATURES = (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2) |
@@ -69,6 +72,15 @@ static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, struct vhost_iotlb *iotlb, u64 start, u64 last, u32 asid); +void vhost_vdpa_lockdep_assert_held(struct vdpa_device *vdpa) +{ + struct vhost_vdpa *v = vdpa_get_drvdata(vdpa); + + if (WARN_ON(!v)) + return; + lockdep_assert_held(&v->vdev.mutex); +} + static inline u32 iotlb_to_asid(struct vhost_iotlb *iotlb) { struct vhost_vdpa_as *as = container_of(iotlb, struct
@@ -497,6 +509,173 @@ static long vhost_vdpa_suspend(struct vhost_vdpa *v) return ops->suspend(vdpa); } +static long vhost_vdpa_tmp_set_iommufd(struct vhost_vdpa *v, void __user *argp) +{ + struct device *dma_dev = vdpa_get_dma_dev(v->vdpa); + struct vhost_vdpa_set_iommufd set_iommufd; + struct vdpa_device *vdpa = v->vdpa; + struct iommufd_ctx *ictx; + unsigned long minsz; + u32 pt_id, dev_id; + struct fd f; + long r = 0; + int idx; + + minsz = offsetofend(struct vhost_vdpa_set_iommufd, ioas_id); + if (copy_from_user(&set_iommufd, argp, minsz)) + return -EFAULT; + + if (set_iommufd.group_id >= v->nvqs) + return -ENOBUFS; + + idx = array_index_nospec(set_iommufd.group_id, v->nvqs); + + /* Unset IOMMUFD */ + if (set_iommufd.iommufd < 0) { + if (!test_bit(idx, vdpa->vq_bitmap)) + return -EINVAL; + + if (!vdpa->iommufd_ictx || !vdpa->iommufd_device) + return -EINVAL; + if (atomic_read(&vdpa->iommufd_users)) { + atomic_dec(&vdpa->iommufd_users); + return 0; + } + vdpa_iommufd_unbind(v->vdpa); + vdpa->iommufd_device = NULL; + vdpa->iommufd_ictx = NULL; + clear_bit(idx, vdpa->vq_bitmap); + return iommu_attach_device(v->domain, dma_dev); + } + /* First opened virtqueue of this vdpa device */ + + if (!vdpa->vq_bitmap) { + vdpa->vq_bitmap = bitmap_alloc(v->nvqs, GFP_KERNEL); + } + ///if (test_bit(idx, vdpa->vq_bitmap)) + //return -EBUSY; + + /* For same device but different groups, ++refcount only */ + if (vdpa->iommufd_device) + goto out_inc; + + r = -EBADF; + f = fdget(set_iommufd.iommufd); + if (!f.file) + goto out_bitmap_free; + + r = -EINVAL; + ictx = iommufd_ctx_from_file(f.file); + if (IS_ERR(ictx)) + goto out_fdput; + + if (v->domain) + iommu_detach_device(v->domain, dma_dev); + +#if 0 + iommu_group_add_device(iommu_group_alloc(), &vdpa->dev); +#endif + pt_id = set_iommufd.ioas_id; + r = vdpa_iommufd_bind(vdpa, ictx, &pt_id, &dev_id); + if (r) + goto out_reattach; + + set_iommufd.out_dev_id = dev_id; + set_iommufd.out_hwpt_id = pt_id; + r = copy_to_user(argp + minsz, &set_iommufd.out_dev_id, + sizeof(set_iommufd.out_dev_id) + + sizeof(set_iommufd.out_hwpt_id)) ? + -EFAULT : + 0; + if (r) + goto out_device_unbind; + printk(KERN_ERR "[%s] %d called %p\n", __func__, __LINE__, + vdpa->iommufd_ictx); + + vdpa->iommufd_ictx = ictx; + +out_inc: + atomic_inc(&vdpa->iommufd_users); + set_bit(idx, vdpa->vq_bitmap); + + goto out_fdput; + +out_device_unbind: + + vdpa_iommufd_unbind(vdpa); +out_reattach: + + iommu_attach_device(v->domain, dma_dev); + iommufd_ctx_put(ictx); +out_fdput: + fdput(f); +out_bitmap_free: + bitmap_free(vdpa->vq_bitmap); + return r; +} +int vdpa_ioctl_device_attach(struct vhost_vdpa *v, void __user *arg) +{ + struct vdpa_device_attach_iommufd_as attach; + unsigned long minsz; + int ret; + + minsz = offsetofend(struct vdpa_device_attach_iommufd_as, ioas_id); + + if (copy_from_user(&attach, (void __user *)arg, minsz)) + return -EFAULT; + + if (attach.argsz < minsz || attach.flags || + attach.ioas_id == IOMMUFD_INVALID_ID) + return -EINVAL; + + if (!v->vdpa->config->bind_iommufd) + return -ENODEV; + + if (!v->vdpa->iommufd_ictx) { + ret = -EINVAL; + return ret; + } + + ret = v->vdpa->config->attach_ioas(v->vdpa, &attach.ioas_id); + + if (ret) + return ret; + + ret = copy_to_user( + (void __user *)arg + + offsetofend(struct vdpa_device_attach_iommufd_as, + flags), + &attach.ioas_id, sizeof(attach.ioas_id)) ? + -EFAULT : + 0; + + if (ret) + return ret; + + return 0; +} + +int vdpa_ioctl_device_detach(struct vhost_vdpa *v, void __user *arg) +{ + struct vdpa_device_detach_iommufd_as detach; + unsigned long minsz; + + minsz = offsetofend(struct vdpa_device_detach_iommufd_as, flags); + + if (copy_from_user(&detach, (void __user *)arg, minsz)) + return -EFAULT; + + if (detach.argsz < minsz || detach.flags) + return -EINVAL; + + if (!v->vdpa->config->bind_iommufd) + return -ENODEV; + + if (v->vdpa->iommufd_ictx) { + return -EINVAL; + } + return v->vdpa->config->detach_ioas(v->vdpa); +} static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd, void __user *argp)
@@ -655,6 +834,18 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, case VHOST_SET_LOG_FD: r = -ENOIOCTLCMD; break; + case VHOST_VDPA_SET_IOMMU_FD: + + r = vhost_vdpa_tmp_set_iommufd(v, argp); + break; + case VDPA_DEVICE_ATTACH_IOMMUFD_AS: + r = vdpa_ioctl_device_attach(v, (void __user *)arg); + break; + + case VDPA_DEVICE_DETACH_IOMMUFD_AS: + r = vdpa_ioctl_device_detach(v, (void __user *)arg); + break; + case VHOST_VDPA_SET_CONFIG_CALL: r = vhost_vdpa_set_config_call(v, argp); break;
diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index f9f115a7c75b..cdda0c1860d8 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h@@ -45,6 +45,7 @@ #define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64) /* Specify an eventfd file descriptor to signal on log write. */ #define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int) +/* Specify an iommufd file descriptor for IO address translation */ /* Ring setup. */ /* Set number of descriptors in ring. This parameter can not
@@ -180,4 +181,74 @@ */ #define VHOST_VDPA_SUSPEND _IO(VHOST_VIRTIO, 0x7D) +/* vhost vdpa set iommufd + * Input parameters: + * @iommufd: file descriptor from /dev/iommu; pass -1 to unset + * @group_id: identifier of the group that a virtqueue belongs to + * @ioas_id: IOAS identifier returned from ioctl(IOMMU_IOAS_ALLOC) + * Output parameters: + * @out_dev_id: device identifier + * @out_hwpt_id: hardware IO pagetable identifier + */ +struct vhost_vdpa_set_iommufd { + __s32 iommufd; + __u32 group_id; + __u32 ioas_id; + __u32 out_dev_id; + __u32 out_hwpt_id; +}; + +#define VHOST_VDPA_SET_IOMMU_FD \ + _IOW(VHOST_VIRTIO, 0x7e, struct vhost_vdpa_set_iommufd) + +/* + * VDPA_DEVICE_ATTACH_IOMMUFD_AS - + * _IOW(VHOST_VIRTIO, 0x7f, struct vdpa_device_attach_iommufd_as) + * + * Attach a vdpa device to an iommufd address space specified by IOAS + * id. + * + * Available only after a device has been bound to iommufd via + * VHOST_VDPA_SET_IOMMU_FD + * + * Undo by VDPA_DEVICE_DETACH_IOMMUFD_AS or device fd close. + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * @ioas_id: Input the target id which can represent an ioas + * allocated via iommufd subsystem. + * + * Return: 0 on success, -errno on failure. + */ +struct vdpa_device_attach_iommufd_as { + __u32 argsz; + __u32 flags; + __u32 ioas_id; +}; + +#define VDPA_DEVICE_ATTACH_IOMMUFD_AS \ + _IOW(VHOST_VIRTIO, 0x7f, struct vdpa_device_attach_iommufd_as) + +/* + * VDPA_DEVICE_DETACH_IOMMUFD_AS + * + * Detach a vdpa device from the iommufd address space it has been + * attached to. After it, device should be in a blocking DMA state. + * + * Available only after a device has been bound to iommufd via + * VHOST_VDPA_SET_IOMMU_FD + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * + * Return: 0 on success, -errno on failure. + */ +struct vdpa_device_detach_iommufd_as { + __u32 argsz; + __u32 flags; +}; + +#define VDPA_DEVICE_DETACH_IOMMUFD_AS \ + _IOW(VHOST_VIRTIO, 0x83, struct vdpa_device_detach_iommufd_as) + #endif
--
2.34.3