From c38ff5b0c373fbbd6a249eb461ffd4ae0f9dbfa0 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Wed, 4 May 2022 16:14:42 -0300 Subject: [PATCH] vfio: Remove vfio_external_group_match_file() vfio_group_fops_open() ensures there is only ever one struct file open for any struct vfio_group at any time: /* Do we need multiple instances of the group open? Seems not. */ opened = atomic_cmpxchg(&group->opened, 0, 1); if (opened) { vfio_group_put(group); return -EBUSY; Therefor the struct file * can be used directly to search the list of VFIO groups that KVM keeps instead of using the vfio_external_group_match_file() callback to try to figure out if the passed in FD matches the list or not. Delete vfio_external_group_match_file(). Reviewed-by: Kevin Tian Reviewed-by: Christoph Hellwig Reviewed-by: Yi Liu Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/4-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.com Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 9 --------- include/linux/vfio.h | 2 -- virt/kvm/vfio.c | 19 +------------------ 3 files changed, 1 insertion(+), 29 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 25f90f3773de..4805e18f2272 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1685,15 +1685,6 @@ void vfio_group_put_external_user(struct vfio_group *group) } EXPORT_SYMBOL_GPL(vfio_group_put_external_user); -bool vfio_external_group_match_file(struct vfio_group *test_group, - struct file *filep) -{ - struct vfio_group *group = filep->private_data; - - return (filep->f_op == &vfio_group_fops) && (group == test_group); -} -EXPORT_SYMBOL_GPL(vfio_external_group_match_file); - /** * vfio_file_iommu_group - Return the struct iommu_group for the vfio group file * @file: VFIO group file diff --git a/include/linux/vfio.h b/include/linux/vfio.h index d8c34c8490cb..df0adecdf1ea 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -138,8 +138,6 @@ int vfio_mig_get_next_state(struct vfio_device *device, */ extern struct vfio_group *vfio_group_get_external_user(struct file *filep); extern void vfio_group_put_external_user(struct vfio_group *group); -extern bool vfio_external_group_match_file(struct vfio_group *group, - struct file *filep); extern struct iommu_group *vfio_file_iommu_group(struct file *file); extern long vfio_external_check_extension(struct vfio_group *group, unsigned long arg); diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c index 9b7384dde158..0b84916c3f71 100644 --- a/virt/kvm/vfio.c +++ b/virt/kvm/vfio.c @@ -49,22 +49,6 @@ static struct vfio_group *kvm_vfio_group_get_external_user(struct file *filep) return vfio_group; } -static bool kvm_vfio_external_group_match_file(struct vfio_group *group, - struct file *filep) -{ - bool ret, (*fn)(struct vfio_group *, struct file *); - - fn = symbol_get(vfio_external_group_match_file); - if (!fn) - return false; - - ret = fn(group, filep); - - symbol_put(vfio_external_group_match_file); - - return ret; -} - static void kvm_vfio_group_put_external_user(struct vfio_group *vfio_group) { void (*fn)(struct vfio_group *); @@ -239,8 +223,7 @@ static int kvm_vfio_group_del(struct kvm_device *dev, unsigned int fd) mutex_lock(&kv->lock); list_for_each_entry(kvg, &kv->group_list, node) { - if (!kvm_vfio_external_group_match_file(kvg->vfio_group, - f.file)) + if (kvg->file != f.file) continue; list_del(&kvg->node);