From b1a59be8a2b64d00409dc7c9d523572ed32bcff8 Mon Sep 17 00:00:00 2001 From: Yi Liu Date: Tue, 18 Jul 2023 06:55:27 -0700 Subject: vfio: Refine vfio file kAPIs for KVM This prepares for making the below kAPIs to accept both group file and device file instead of only vfio group file. bool vfio_file_enforced_coherent(struct file *file); void vfio_file_set_kvm(struct file *file, struct kvm *kvm); Reviewed-by: Kevin Tian Reviewed-by: Eric Auger 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/20230718135551.6592-3-yi.l.liu@intel.com Signed-off-by: Alex Williamson --- drivers/vfio/group.c | 53 ++++++++++++++++-------------------------------- drivers/vfio/vfio.h | 3 +++ drivers/vfio/vfio_main.c | 49 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/vfio.h | 1 + virt/kvm/vfio.c | 10 ++++----- 5 files changed, 75 insertions(+), 41 deletions(-) diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index fbba9fc15e57..b56e19d2a02d 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -754,6 +754,15 @@ bool vfio_device_has_container(struct vfio_device *device) return device->group->container; } +struct vfio_group *vfio_group_from_file(struct file *file) +{ + struct vfio_group *group = file->private_data; + + if (file->f_op != &vfio_group_fops) + return NULL; + return group; +} + /** * vfio_file_iommu_group - Return the struct iommu_group for the vfio group file * @file: VFIO group file @@ -764,13 +773,13 @@ bool vfio_device_has_container(struct vfio_device *device) */ struct iommu_group *vfio_file_iommu_group(struct file *file) { - struct vfio_group *group = file->private_data; + struct vfio_group *group = vfio_group_from_file(file); struct iommu_group *iommu_group = NULL; if (!IS_ENABLED(CONFIG_SPAPR_TCE_IOMMU)) return NULL; - if (!vfio_file_is_group(file)) + if (!group) return NULL; mutex_lock(&group->group_lock); @@ -784,33 +793,20 @@ struct iommu_group *vfio_file_iommu_group(struct file *file) EXPORT_SYMBOL_GPL(vfio_file_iommu_group); /** - * vfio_file_is_group - True if the file is usable with VFIO aPIS + * vfio_file_is_group - True if the file is a vfio group file * @file: VFIO group file */ bool vfio_file_is_group(struct file *file) { - return file->f_op == &vfio_group_fops; + return vfio_group_from_file(file); } EXPORT_SYMBOL_GPL(vfio_file_is_group); -/** - * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file - * is always CPU cache coherent - * @file: VFIO group file - * - * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop - * bit in DMA transactions. A return of false indicates that the user has - * rights to access additional instructions such as wbinvd on x86. - */ -bool vfio_file_enforced_coherent(struct file *file) +bool vfio_group_enforced_coherent(struct vfio_group *group) { - struct vfio_group *group = file->private_data; struct vfio_device *device; bool ret = true; - if (!vfio_file_is_group(file)) - return true; - /* * If the device does not have IOMMU_CAP_ENFORCE_CACHE_COHERENCY then * any domain later attached to it will also not support it. If the cap @@ -828,28 +824,13 @@ bool vfio_file_enforced_coherent(struct file *file) mutex_unlock(&group->device_lock); return ret; } -EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); -/** - * vfio_file_set_kvm - Link a kvm with VFIO drivers - * @file: VFIO group file - * @kvm: KVM to link - * - * When a VFIO device is first opened the KVM will be available in - * device->kvm if one was associated with the group. - */ -void vfio_file_set_kvm(struct file *file, struct kvm *kvm) +void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm) { - struct vfio_group *group = file->private_data; - - if (!vfio_file_is_group(file)) - return; - spin_lock(&group->kvm_ref_lock); group->kvm = kvm; spin_unlock(&group->kvm_ref_lock); } -EXPORT_SYMBOL_GPL(vfio_file_set_kvm); /** * vfio_file_has_dev - True if the VFIO file is a handle for device @@ -860,9 +841,9 @@ EXPORT_SYMBOL_GPL(vfio_file_set_kvm); */ bool vfio_file_has_dev(struct file *file, struct vfio_device *device) { - struct vfio_group *group = file->private_data; + struct vfio_group *group = vfio_group_from_file(file); - if (!vfio_file_is_group(file)) + if (!group) return false; return group == device->group; diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index 87d3dd6b9ef9..b1e327a85a32 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -90,6 +90,9 @@ void vfio_device_group_unregister(struct vfio_device *device); int vfio_device_group_use_iommu(struct vfio_device *device); void vfio_device_group_unuse_iommu(struct vfio_device *device); void vfio_device_group_close(struct vfio_device *device); +struct vfio_group *vfio_group_from_file(struct file *file); +bool vfio_group_enforced_coherent(struct vfio_group *group); +void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm); bool vfio_device_has_container(struct vfio_device *device); int __init vfio_group_init(void); void vfio_group_cleanup(void); diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 39c1158ffef0..4665791aa2eb 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -1190,6 +1190,55 @@ const struct file_operations vfio_device_fops = { .mmap = vfio_device_fops_mmap, }; +/** + * 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); +} +EXPORT_SYMBOL_GPL(vfio_file_is_valid); + +/** + * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file + * is always CPU cache coherent + * @file: VFIO group file or VFIO device file + * + * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop + * bit in DMA transactions. A return of false indicates that the user has + * rights to access additional instructions such as wbinvd on x86. + */ +bool vfio_file_enforced_coherent(struct file *file) +{ + struct vfio_group *group; + + group = vfio_group_from_file(file); + if (group) + return vfio_group_enforced_coherent(group); + + return true; +} +EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); + +/** + * vfio_file_set_kvm - Link a kvm with VFIO drivers + * @file: VFIO group file or VFIO device file + * @kvm: KVM to link + * + * When a VFIO device is first opened the KVM will be available in + * device->kvm if one was associated with the file. + */ +void vfio_file_set_kvm(struct file *file, struct kvm *kvm) +{ + struct vfio_group *group; + + group = vfio_group_from_file(file); + if (group) + vfio_group_set_kvm(group, kvm); +} +EXPORT_SYMBOL_GPL(vfio_file_set_kvm); + /* * Sub-module support */ diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 7079911edfb1..06a5221949c5 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -272,6 +272,7 @@ int vfio_mig_get_next_state(struct vfio_device *device, */ struct iommu_group *vfio_file_iommu_group(struct file *file); bool vfio_file_is_group(struct file *file); +bool vfio_file_is_valid(struct file *file); bool vfio_file_enforced_coherent(struct file *file); void vfio_file_set_kvm(struct file *file, struct kvm *kvm); bool vfio_file_has_dev(struct file *file, struct vfio_device *device); diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c index 9584eb57e0ed..b33c7b8488b3 100644 --- a/virt/kvm/vfio.c +++ b/virt/kvm/vfio.c @@ -64,18 +64,18 @@ static bool kvm_vfio_file_enforced_coherent(struct file *file) return ret; } -static bool kvm_vfio_file_is_group(struct file *file) +static bool kvm_vfio_file_is_valid(struct file *file) { bool (*fn)(struct file *file); bool ret; - fn = symbol_get(vfio_file_is_group); + fn = symbol_get(vfio_file_is_valid); if (!fn) return false; ret = fn(file); - symbol_put(vfio_file_is_group); + symbol_put(vfio_file_is_valid); return ret; } @@ -154,8 +154,8 @@ static int kvm_vfio_group_add(struct kvm_device *dev, unsigned int fd) if (!filp) return -EBADF; - /* Ensure the FD is a vfio group FD.*/ - if (!kvm_vfio_file_is_group(filp)) { + /* Ensure the FD is a vfio FD. */ + if (!kvm_vfio_file_is_valid(filp)) { ret = -EINVAL; goto err_fput; } -- cgit