diff options
| author | Steffen Eiden <seiden@linux.ibm.com> | 2026-09-28 15:07:05 +0200 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@linux.ibm.com> | 2026-10-02 10:40:00 +0200 |
| commit | 5c3ea6d3e836debc1f7f5518a5ec0c7e058fb04a (patch) | |
| tree | 0d522d481d0ab255af411d8a74bbe2613ac47f25 /include/linux | |
| parent | 77037cf77a3c1b575e514a483527d88c12bb682c (diff) | |
KVM/vfio: Use file-based reference counting for KVM
Replace manual module reference counting with file-based reference
counting for KVM integration. Previously, VFIO used symbol_get() to
obtain function pointers for kvm_get_kvm_safe() and kvm_put_kvm(),
then manually tracked module references through these symbols. This
approach required storing the put_kvm function pointer in each device
and carefully managing symbol references.
Pass struct file pointers instead of struct kvm pointers throughout the
VFIO-KVM interface, leveraging the kernel's existing file reference
counting via get_file()/get_file_active() and fput(). Convert the x86
page-track API and update s390 vfio to use file_to_kvm_<arch>(). This
simplifies the code.
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Acked-by: Alex Williamson <alex@shazbot.org>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Sean Christopherson <seanjc@google.com>
[borntraeger@linux.ibm.com remove _safe from vfio_device_get_kvm_safe]
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/vfio.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 45f08986359e..0cc91c6f96d2 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -54,7 +54,7 @@ struct vfio_device { struct list_head dev_set_list; unsigned int migration_flags; u8 precopy_info_v2; - struct kvm *kvm; + struct file *kvm; /* Members below here are private, not for driver use */ unsigned int index; @@ -66,7 +66,6 @@ struct vfio_device { unsigned int open_count; struct completion comp; struct iommufd_access *iommufd_access; - void (*put_kvm)(struct kvm *kvm); struct inode *inode; #if IS_ENABLED(CONFIG_IOMMUFD) struct iommufd_device *iommufd_device; @@ -378,7 +377,7 @@ static inline bool vfio_file_has_dev(struct file *file, struct vfio_device *devi #endif 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); +void vfio_file_set_kvm(struct file *vfio_file, struct file *kvm); #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long)) |