Re: [PATCH v7 2/4] iommu: Move global PASID allocation from SVA to core

From: Jacob Pan
Date: Thu May 25 2023 - 11:50:39 EST


Hi Kevin,

On Thu, 25 May 2023 06:27:40 +0000, "Tian, Kevin" <kevin.tian@xxxxxxxxx>
wrote:

> > From: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> > Sent: Wednesday, May 24, 2023 1:35 AM
> >
> > /* Allocate a PASID for the mm within range (inclusive) */
> > -static int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min,
> > ioasid_t max)
> > +static int iommu_sva_alloc_pasid(struct mm_struct *mm, struct device
> > *dev) {
> > + ioasid_t pasid;
> > int ret = 0;
> >
> > - if (min == IOMMU_PASID_INVALID ||
> > - max == IOMMU_PASID_INVALID ||
> > - min == 0 || max < min)
> > - return -EINVAL;
> > -
> > if (!arch_pgtable_dma_compat(mm))
> > return -EBUSY;
> >
> > mutex_lock(&iommu_sva_lock);
> > /* Is a PASID already associated with this mm? */
> > if (mm_valid_pasid(mm)) {
> > - if (mm->pasid < min || mm->pasid > max)
> > + if (mm->pasid > dev->iommu->max_pasids)
>
> ">" should be ">="
right, will do

> > +ioasid_t iommu_alloc_global_pasid_dev(struct device *dev)
> > +{
> > + int ret;
> > + ioasid_t max;
> > +
> > + max = dev->iommu->max_pasids;
> > + ret = ida_alloc_range(&iommu_global_pasid_ida,
> > IOMMU_FIRST_GLOBAL_PASID, max, GFP_KERNEL);
>
> max is inclusive. Here should minus one.
yeah, should be -1

> otherwise looks good to me,
>
> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>


Thanks,

Jacob