From 34aeeecdb3357f9ca5aea549525a17790d1c427d Mon Sep 17 00:00:00 2001 From: Yi Liu Date: Tue, 18 Jul 2023 06:55:28 -0700 Subject: vfio: Accept vfio device file in the KVM facing kAPI This makes the vfio file kAPIs to accept vfio device files, also a preparation for vfio device cdev support. For the kvm set with vfio device file, kvm pointer is stored in struct vfio_device_file, and use kvm_ref_lock to protect kvm set and kvm pointer usage within VFIO. This kvm pointer will be set to vfio_device after device file is bound to iommufd in the cdev path. Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Tested-by: Terrence Xu Tested-by: Nicolin Chen Tested-by: Matthew Rosato Tested-by: Yanting Jiang Tested-by: Shameer Kolothum Tested-by: Zhenzhong Duan Signed-off-by: Yi Liu Link: https://lore.kernel.org/r/20230718135551.6592-4-yi.l.liu@intel.com Signed-off-by: Alex Williamson --- drivers/vfio/vfio_main.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) (limited to 'drivers/vfio/vfio_main.c') diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 4665791aa2eb..8ef9210ad2aa 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -429,6 +429,7 @@ vfio_allocate_device_file(struct vfio_device *device) return ERR_PTR(-ENOMEM); df->device = device; + spin_lock_init(&df->kvm_ref_lock); return df; } @@ -1190,13 +1191,23 @@ const struct file_operations vfio_device_fops = { .mmap = vfio_device_fops_mmap, }; +static struct vfio_device *vfio_device_from_file(struct file *file) +{ + struct vfio_device_file *df = file->private_data; + + if (file->f_op != &vfio_device_fops) + return NULL; + return df->device; +} + /** * vfio_file_is_valid - True if the file is valid vfio file * @file: VFIO group file or VFIO device file */ bool vfio_file_is_valid(struct file *file) { - return vfio_group_from_file(file); + return vfio_group_from_file(file) || + vfio_device_from_file(file); } EXPORT_SYMBOL_GPL(vfio_file_is_valid); @@ -1211,16 +1222,36 @@ EXPORT_SYMBOL_GPL(vfio_file_is_valid); */ bool vfio_file_enforced_coherent(struct file *file) { + struct vfio_device *device; struct vfio_group *group; group = vfio_group_from_file(file); if (group) return vfio_group_enforced_coherent(group); + device = vfio_device_from_file(file); + if (device) + return device_iommu_capable(device->dev, + IOMMU_CAP_ENFORCE_CACHE_COHERENCY); + return true; } EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); +static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm) +{ + struct vfio_device_file *df = file->private_data; + + /* + * The kvm is first recorded in the vfio_device_file, and will + * be propagated to vfio_device::kvm when the file is bound to + * iommufd successfully in the vfio device cdev path. + */ + spin_lock(&df->kvm_ref_lock); + df->kvm = kvm; + spin_unlock(&df->kvm_ref_lock); +} + /** * vfio_file_set_kvm - Link a kvm with VFIO drivers * @file: VFIO group file or VFIO device file @@ -1236,6 +1267,9 @@ void vfio_file_set_kvm(struct file *file, struct kvm *kvm) group = vfio_group_from_file(file); if (group) vfio_group_set_kvm(group, kvm); + + if (vfio_device_from_file(file)) + vfio_device_file_set_kvm(file, kvm); } EXPORT_SYMBOL_GPL(vfio_file_set_kvm); -- cgit v1.2.3