Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
iommufd/device: Wrap igroup->hwpt and igroup->device_list into attach struct
The igroup->hwpt and igroup->device_list are used to track the hwpt attach
of a group in the RID path. While the coming PASID path also needs such
tracking. To be prepared, wrap igroup->hwpt and igroup->device_list into
attach struct which is allocated per attaching the first device of the
group and freed per detaching the last device of the group.
Link: https://patch.msgid.link/r/20250321171940.7213-8-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
authored by
Yi Liu
and committed by
Jason Gunthorpe
75f990ae
ba1de6cd
+58
-23
+55
-21
drivers/iommu/iommufd/device.c
+55
-21
drivers/iommu/iommufd/device.c
···
17
17
"Allow IOMMUFD to bind to devices even if the platform cannot isolate "
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"the MSI interrupt window. Enabling this is a security weakness.");
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+
struct iommufd_attach {
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+
struct iommufd_hw_pagetable *hwpt;
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+
struct list_head device_list;
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+
};
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+
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static void iommufd_group_release(struct kref *kref)
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{
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struct iommufd_group *igroup =
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container_of(kref, struct iommufd_group, ref);
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-
WARN_ON(igroup->hwpt || !list_empty(&igroup->device_list));
30
+
WARN_ON(igroup->attach);
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xa_cmpxchg(&igroup->ictx->groups, iommu_group_id(igroup->group), igroup,
28
33
NULL, GFP_KERNEL);
···
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kref_init(&new_igroup->ref);
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mutex_init(&new_igroup->lock);
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-
INIT_LIST_HEAD(&new_igroup->device_list);
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new_igroup->sw_msi_start = PHYS_ADDR_MAX;
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/* group reference moves into new_igroup */
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new_igroup->group = group;
···
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iommufd_group_first_attach(struct iommufd_group *igroup, ioasid_t pasid)
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{
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lockdep_assert_held(&igroup->lock);
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-
return !igroup->hwpt;
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+
return !igroup->attach;
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}
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static int
···
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{
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struct iommufd_device *cur;
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-
list_for_each_entry(cur, &idev->igroup->device_list, group_item)
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+
list_for_each_entry(cur, &idev->igroup->attach->device_list, group_item)
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if (cur == idev)
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return true;
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return false;
···
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struct iommufd_hwpt_paging *hwpt_paging = find_hwpt_paging(hwpt);
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bool attach_resv = hwpt_paging && pasid == IOMMU_NO_PASID;
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struct iommufd_group *igroup = idev->igroup;
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+
struct iommufd_hw_pagetable *old_hwpt;
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+
struct iommufd_attach *attach;
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int rc;
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mutex_lock(&igroup->lock);
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501
504
-
if (igroup->hwpt && igroup->hwpt != hwpt) {
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+
attach = igroup->attach;
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+
if (!attach) {
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+
attach = kzalloc(sizeof(*attach), GFP_KERNEL);
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+
if (!attach) {
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+
rc = -ENOMEM;
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+
goto err_unlock;
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+
}
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INIT_LIST_HEAD(&attach->device_list);
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+
}
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+
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+
old_hwpt = attach->hwpt;
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+
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+
if (old_hwpt && old_hwpt != hwpt) {
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rc = -EINVAL;
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-
goto err_unlock;
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+
goto err_free_attach;
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}
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if (attach_resv) {
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rc = iommufd_device_attach_reserved_iova(idev, hwpt_paging);
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if (rc)
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-
goto err_unlock;
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+
goto err_free_attach;
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}
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525
/*
···
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rc = iommufd_hwpt_attach_device(hwpt, idev, pasid);
538
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if (rc)
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goto err_unresv;
540
-
igroup->hwpt = hwpt;
522
+
attach->hwpt = hwpt;
523
+
igroup->attach = attach;
541
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}
542
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refcount_inc(&hwpt->obj.users);
543
-
list_add_tail(&idev->group_item, &igroup->device_list);
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+
list_add_tail(&idev->group_item, &attach->device_list);
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mutex_unlock(&igroup->lock);
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return 0;
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err_unresv:
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if (attach_resv)
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531
iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, idev->dev);
532
+
err_free_attach:
533
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if (iommufd_group_first_attach(igroup, pasid))
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kfree(attach);
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err_unlock:
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mutex_unlock(&igroup->lock);
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return rc;
···
559
537
iommufd_hw_pagetable_detach(struct iommufd_device *idev, ioasid_t pasid)
560
538
{
561
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struct iommufd_group *igroup = idev->igroup;
562
-
struct iommufd_hw_pagetable *hwpt = igroup->hwpt;
563
-
struct iommufd_hwpt_paging *hwpt_paging = find_hwpt_paging(hwpt);
540
+
struct iommufd_hwpt_paging *hwpt_paging;
541
+
struct iommufd_hw_pagetable *hwpt;
542
+
struct iommufd_attach *attach;
564
543
565
544
mutex_lock(&igroup->lock);
545
+
attach = igroup->attach;
546
+
hwpt = attach->hwpt;
547
+
hwpt_paging = find_hwpt_paging(hwpt);
548
+
566
549
list_del(&idev->group_item);
567
-
if (list_empty(&igroup->device_list)) {
550
+
if (list_empty(&attach->device_list)) {
568
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iommufd_hwpt_detach_device(hwpt, idev, pasid);
569
-
igroup->hwpt = NULL;
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+
igroup->attach = NULL;
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+
kfree(attach);
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}
571
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if (hwpt_paging && pasid == IOMMU_NO_PASID)
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iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, idev->dev);
···
602
574
603
575
lockdep_assert_held(&igroup->lock);
604
576
605
-
list_for_each_entry(cur, &igroup->device_list, group_item)
577
+
list_for_each_entry(cur, &igroup->attach->device_list, group_item)
606
578
iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, cur->dev);
607
579
}
608
580
···
616
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617
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lockdep_assert_held(&igroup->lock);
618
590
619
-
old_hwpt_paging = find_hwpt_paging(igroup->hwpt);
591
+
old_hwpt_paging = find_hwpt_paging(igroup->attach->hwpt);
620
592
if (!old_hwpt_paging || hwpt_paging->ioas != old_hwpt_paging->ioas) {
621
-
list_for_each_entry(cur, &igroup->device_list, group_item) {
593
+
list_for_each_entry(cur,
594
+
&igroup->attach->device_list, group_item) {
622
595
rc = iopt_table_enforce_dev_resv_regions(
623
596
&hwpt_paging->ioas->iopt, cur->dev, NULL);
624
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if (rc)
···
646
617
struct iommufd_hwpt_paging *old_hwpt_paging;
647
618
struct iommufd_group *igroup = idev->igroup;
648
619
struct iommufd_hw_pagetable *old_hwpt;
620
+
struct iommufd_attach *attach;
649
621
unsigned int num_devices;
650
622
int rc;
651
623
652
624
mutex_lock(&igroup->lock);
653
625
654
-
if (igroup->hwpt == NULL) {
626
+
attach = igroup->attach;
627
+
if (!attach) {
655
628
rc = -EINVAL;
656
629
goto err_unlock;
657
630
}
631
+
632
+
old_hwpt = attach->hwpt;
633
+
634
+
WARN_ON(!old_hwpt || list_empty(&attach->device_list));
658
635
659
636
if (!iommufd_device_is_attached(idev)) {
660
637
rc = -EINVAL;
661
638
goto err_unlock;
662
639
}
663
640
664
-
if (hwpt == igroup->hwpt) {
641
+
if (hwpt == old_hwpt) {
665
642
mutex_unlock(&igroup->lock);
666
643
return NULL;
667
644
}
668
645
669
-
old_hwpt = igroup->hwpt;
670
646
if (attach_resv) {
671
647
rc = iommufd_group_do_replace_reserved_iova(igroup, hwpt_paging);
672
648
if (rc)
···
687
653
(!hwpt_paging || hwpt_paging->ioas != old_hwpt_paging->ioas))
688
654
iommufd_group_remove_reserved_iova(igroup, old_hwpt_paging);
689
655
690
-
igroup->hwpt = hwpt;
656
+
attach->hwpt = hwpt;
691
657
692
-
num_devices = list_count_nodes(&igroup->device_list);
658
+
num_devices = list_count_nodes(&attach->device_list);
693
659
/*
694
660
* Move the refcounts held by the device_list to the new hwpt. Retain a
695
661
* refcount for this thread as the caller will free it.
+3
-2
drivers/iommu/iommufd/iommufd_private.h
+3
-2
drivers/iommu/iommufd/iommufd_private.h
···
399
399
refcount_dec(&hwpt->obj.users);
400
400
}
401
401
402
+
struct iommufd_attach;
403
+
402
404
struct iommufd_group {
403
405
struct kref ref;
404
406
struct mutex lock;
405
407
struct iommufd_ctx *ictx;
406
408
struct iommu_group *group;
407
-
struct iommufd_hw_pagetable *hwpt;
408
-
struct list_head device_list;
409
+
struct iommufd_attach *attach;
409
410
struct iommufd_sw_msi_maps required_sw_msi;
410
411
phys_addr_t sw_msi_start;
411
412
};