hisi_acc_vfio_pci: Add support for precopy IOCTL

PRECOPY IOCTL in the case of HiSiIicon ACC driver can be used to
perform the device compatibility check earlier during migration.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20221123113236.896-2-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index 0c0c0c7f05215e7811007b53e13ea1064510958c..f3b74a06edb6864d247d84b2f87fe6bfcd75e168 100644 (file)
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -764,9 +764,58 @@ hisi_acc_vf_pci_resume(struct hisi_acc_vf_core_device *hisi_acc_vdev)
 
        stream_open(migf->filp->f_inode, migf->filp);
        mutex_init(&migf->lock);
+       migf->hisi_acc_vdev = hisi_acc_vdev;
        return migf;
 }
 
+static long hisi_acc_vf_precopy_ioctl(struct file *filp,
+                                     unsigned int cmd, unsigned long arg)
+{
+       struct hisi_acc_vf_migration_file *migf = filp->private_data;
+       struct hisi_acc_vf_core_device *hisi_acc_vdev = migf->hisi_acc_vdev;
+       loff_t *pos = &filp->f_pos;
+       struct vfio_precopy_info info;
+       unsigned long minsz;
+       int ret;
+
+       if (cmd != VFIO_MIG_GET_PRECOPY_INFO)
+               return -ENOTTY;
+
+       minsz = offsetofend(struct vfio_precopy_info, dirty_bytes);
+
+       if (copy_from_user(&info, (void __user *)arg, minsz))
+               return -EFAULT;
+       if (info.argsz < minsz)
+               return -EINVAL;
+
+       mutex_lock(&hisi_acc_vdev->state_mutex);
+       if (hisi_acc_vdev->mig_state != VFIO_DEVICE_STATE_PRE_COPY) {
+               mutex_unlock(&hisi_acc_vdev->state_mutex);
+               return -EINVAL;
+       }
+
+       mutex_lock(&migf->lock);
+
+       if (migf->disabled) {
+               ret = -ENODEV;
+               goto out;
+       }
+
+       if (*pos > migf->total_length) {
+               ret = -EINVAL;
+               goto out;
+       }
+
+       info.dirty_bytes = 0;
+       info.initial_bytes = migf->total_length - *pos;
+
+       ret = copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
+out:
+       mutex_unlock(&migf->lock);
+       mutex_unlock(&hisi_acc_vdev->state_mutex);
+       return ret;
+}
+
 static ssize_t hisi_acc_vf_save_read(struct file *filp, char __user *buf, size_t len,
                                     loff_t *pos)
 {
@@ -807,6 +856,8 @@ out_unlock:
 static const struct file_operations hisi_acc_vf_save_fops = {
        .owner = THIS_MODULE,
        .read = hisi_acc_vf_save_read,
+       .unlocked_ioctl = hisi_acc_vf_precopy_ioctl,
+       .compat_ioctl = compat_ptr_ioctl,
        .release = hisi_acc_vf_release_file,
        .llseek = no_llseek,
 };
@@ -832,6 +883,7 @@ hisi_acc_vf_stop_copy(struct hisi_acc_vf_core_device *hisi_acc_vdev)
 
        stream_open(migf->filp->f_inode, migf->filp);
        mutex_init(&migf->lock);
+       migf->hisi_acc_vdev = hisi_acc_vdev;
 
        ret = vf_qm_state_save(hisi_acc_vdev, migf);
        if (ret) {

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
index 67343325b320165499a6e17bea7e6d9cc9b7e7c3..11d51345f5b511db16397699ba066f886c5191f6 100644 (file)
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h
@@ -91,6 +91,7 @@ struct hisi_acc_vf_migration_file {
        struct mutex lock;
        bool disabled;
 
+       struct hisi_acc_vf_core_device *hisi_acc_vdev;
        struct acc_vf_data vf_data;
        size_t total_length;
 };