iommufd/device: Add pasid_attach array to track per-PASID attach

PASIDs of PASID-capable device can be attached to hwpt separately, hence
a pasid array to track per-PASID attachment is necessary. The index
IOMMU_NO_PASID is used by the RID path. Hence drop the igroup->attach.

Link: https://patch.msgid.link/r/20250321171940.7213-10-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@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>
This commit is contained in:
Yi Liu 2025-03-21 10:19:31 -07:00 committed by Jason Gunthorpe
parent 831b40f841
commit c0e301b297
2 changed files with 41 additions and 20 deletions

View File

@ -27,7 +27,7 @@ static void iommufd_group_release(struct kref *kref)
struct iommufd_group *igroup =
container_of(kref, struct iommufd_group, ref);
WARN_ON(igroup->attach);
WARN_ON(!xa_empty(&igroup->pasid_attach));
xa_cmpxchg(&igroup->ictx->groups, iommu_group_id(igroup->group), igroup,
NULL, GFP_KERNEL);
@ -94,6 +94,7 @@ static struct iommufd_group *iommufd_get_group(struct iommufd_ctx *ictx,
kref_init(&new_igroup->ref);
mutex_init(&new_igroup->lock);
xa_init(&new_igroup->pasid_attach);
new_igroup->sw_msi_start = PHYS_ADDR_MAX;
/* group reference moves into new_igroup */
new_igroup->group = group;
@ -297,16 +298,19 @@ u32 iommufd_device_to_id(struct iommufd_device *idev)
}
EXPORT_SYMBOL_NS_GPL(iommufd_device_to_id, "IOMMUFD");
static unsigned int iommufd_group_device_num(struct iommufd_group *igroup)
static unsigned int iommufd_group_device_num(struct iommufd_group *igroup,
ioasid_t pasid)
{
struct iommufd_attach *attach;
struct iommufd_device *idev;
unsigned int count = 0;
unsigned long index;
lockdep_assert_held(&igroup->lock);
if (igroup->attach)
xa_for_each(&igroup->attach->device_array, index, idev)
attach = xa_load(&igroup->pasid_attach, pasid);
if (attach)
xa_for_each(&attach->device_array, index, idev)
count++;
return count;
}
@ -351,7 +355,7 @@ static bool
iommufd_group_first_attach(struct iommufd_group *igroup, ioasid_t pasid)
{
lockdep_assert_held(&igroup->lock);
return !igroup->attach;
return !xa_load(&igroup->pasid_attach, pasid);
}
static int
@ -382,10 +386,13 @@ iommufd_device_attach_reserved_iova(struct iommufd_device *idev,
/* The device attach/detach/replace helpers for attach_handle */
/* Check if idev is attached to igroup->hwpt */
static bool iommufd_device_is_attached(struct iommufd_device *idev)
static bool iommufd_device_is_attached(struct iommufd_device *idev,
ioasid_t pasid)
{
return xa_load(&idev->igroup->attach->device_array, idev->obj.id);
struct iommufd_attach *attach;
attach = xa_load(&idev->igroup->pasid_attach, pasid);
return xa_load(&attach->device_array, idev->obj.id);
}
static int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt,
@ -512,12 +519,18 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
mutex_lock(&igroup->lock);
attach = igroup->attach;
attach = xa_cmpxchg(&igroup->pasid_attach, pasid, NULL,
XA_ZERO_ENTRY, GFP_KERNEL);
if (xa_is_err(attach)) {
rc = xa_err(attach);
goto err_unlock;
}
if (!attach) {
attach = kzalloc(sizeof(*attach), GFP_KERNEL);
if (!attach) {
rc = -ENOMEM;
goto err_unlock;
goto err_release_pasid;
}
xa_init(&attach->device_array);
}
@ -554,7 +567,8 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
if (rc)
goto err_unresv;
attach->hwpt = hwpt;
igroup->attach = attach;
WARN_ON(xa_is_err(xa_store(&igroup->pasid_attach, pasid, attach,
GFP_KERNEL)));
}
refcount_inc(&hwpt->obj.users);
WARN_ON(xa_is_err(xa_store(&attach->device_array, idev->obj.id,
@ -569,6 +583,9 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
err_free_attach:
if (iommufd_group_first_attach(igroup, pasid))
kfree(attach);
err_release_pasid:
if (iommufd_group_first_attach(igroup, pasid))
xa_release(&igroup->pasid_attach, pasid);
err_unlock:
mutex_unlock(&igroup->lock);
return rc;
@ -583,14 +600,14 @@ iommufd_hw_pagetable_detach(struct iommufd_device *idev, ioasid_t pasid)
struct iommufd_attach *attach;
mutex_lock(&igroup->lock);
attach = igroup->attach;
attach = xa_load(&igroup->pasid_attach, pasid);
hwpt = attach->hwpt;
hwpt_paging = find_hwpt_paging(hwpt);
xa_erase(&attach->device_array, idev->obj.id);
if (xa_empty(&attach->device_array)) {
iommufd_hwpt_detach_device(hwpt, idev, pasid);
igroup->attach = NULL;
xa_erase(&igroup->pasid_attach, pasid);
kfree(attach);
}
if (hwpt_paging && pasid == IOMMU_NO_PASID)
@ -617,12 +634,14 @@ static void
iommufd_group_remove_reserved_iova(struct iommufd_group *igroup,
struct iommufd_hwpt_paging *hwpt_paging)
{
struct iommufd_attach *attach;
struct iommufd_device *cur;
unsigned long index;
lockdep_assert_held(&igroup->lock);
xa_for_each(&igroup->attach->device_array, index, cur)
attach = xa_load(&igroup->pasid_attach, IOMMU_NO_PASID);
xa_for_each(&attach->device_array, index, cur)
iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt, cur->dev);
}
@ -631,15 +650,17 @@ iommufd_group_do_replace_reserved_iova(struct iommufd_group *igroup,
struct iommufd_hwpt_paging *hwpt_paging)
{
struct iommufd_hwpt_paging *old_hwpt_paging;
struct iommufd_attach *attach;
struct iommufd_device *cur;
unsigned long index;
int rc;
lockdep_assert_held(&igroup->lock);
old_hwpt_paging = find_hwpt_paging(igroup->attach->hwpt);
attach = xa_load(&igroup->pasid_attach, IOMMU_NO_PASID);
old_hwpt_paging = find_hwpt_paging(attach->hwpt);
if (!old_hwpt_paging || hwpt_paging->ioas != old_hwpt_paging->ioas) {
xa_for_each(&igroup->attach->device_array, index, cur) {
xa_for_each(&attach->device_array, index, cur) {
rc = iopt_table_enforce_dev_resv_regions(
&hwpt_paging->ioas->iopt, cur->dev, NULL);
if (rc)
@ -672,7 +693,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
mutex_lock(&igroup->lock);
attach = igroup->attach;
attach = xa_load(&igroup->pasid_attach, pasid);
if (!attach) {
rc = -EINVAL;
goto err_unlock;
@ -682,7 +703,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
WARN_ON(!old_hwpt || xa_empty(&attach->device_array));
if (!iommufd_device_is_attached(idev)) {
if (!iommufd_device_is_attached(idev, pasid)) {
rc = -EINVAL;
goto err_unlock;
}
@ -709,7 +730,7 @@ iommufd_device_do_replace(struct iommufd_device *idev, ioasid_t pasid,
attach->hwpt = hwpt;
num_devices = iommufd_group_device_num(igroup);
num_devices = iommufd_group_device_num(igroup, pasid);
/*
* Move the refcounts held by the device_array to the new hwpt. Retain a
* refcount for this thread as the caller will free it.

View File

@ -406,7 +406,7 @@ struct iommufd_group {
struct mutex lock;
struct iommufd_ctx *ictx;
struct iommu_group *group;
struct iommufd_attach *attach;
struct xarray pasid_attach;
struct iommufd_sw_msi_maps required_sw_msi;
phys_addr_t sw_msi_start;
};