iommu/amd: Implement functions to manage GCR3 table
This patch adds functions necessary to set and clear the
GCR3 values associated with a particular PASID in an IOMMUv2
domain.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index b086173..65a118c 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1637,8 +1637,45 @@
domain->pt_root = NULL;
}
+static void free_gcr3_tbl_level1(u64 *tbl)
+{
+ u64 *ptr;
+ int i;
+
+ for (i = 0; i < 512; ++i) {
+ if (!(tbl[i] & GCR3_VALID))
+ continue;
+
+ ptr = __va(tbl[i] & PAGE_MASK);
+
+ free_page((unsigned long)ptr);
+ }
+}
+
+static void free_gcr3_tbl_level2(u64 *tbl)
+{
+ u64 *ptr;
+ int i;
+
+ for (i = 0; i < 512; ++i) {
+ if (!(tbl[i] & GCR3_VALID))
+ continue;
+
+ ptr = __va(tbl[i] & PAGE_MASK);
+
+ free_gcr3_tbl_level1(ptr);
+ }
+}
+
static void free_gcr3_table(struct protection_domain *domain)
{
+ if (domain->glx == 2)
+ free_gcr3_tbl_level2(domain->gcr3_tbl);
+ else if (domain->glx == 1)
+ free_gcr3_tbl_level1(domain->gcr3_tbl);
+ else if (domain->glx != 0)
+ BUG();
+
free_page((unsigned long)domain->gcr3_tbl);
}
@@ -3282,3 +3319,96 @@
}
EXPORT_SYMBOL(amd_iommu_flush_tlb);
+static u64 *__get_gcr3_pte(u64 *root, int level, int pasid, bool alloc)
+{
+ int index;
+ u64 *pte;
+
+ while (true) {
+
+ index = (pasid >> (9 * level)) & 0x1ff;
+ pte = &root[index];
+
+ if (level == 0)
+ break;
+
+ if (!(*pte & GCR3_VALID)) {
+ if (!alloc)
+ return NULL;
+
+ root = (void *)get_zeroed_page(GFP_ATOMIC);
+ if (root == NULL)
+ return NULL;
+
+ *pte = __pa(root) | GCR3_VALID;
+ }
+
+ root = __va(*pte & PAGE_MASK);
+
+ level -= 1;
+ }
+
+ return pte;
+}
+
+static int __set_gcr3(struct protection_domain *domain, int pasid,
+ unsigned long cr3)
+{
+ u64 *pte;
+
+ if (domain->mode != PAGE_MODE_NONE)
+ return -EINVAL;
+
+ pte = __get_gcr3_pte(domain->gcr3_tbl, domain->glx, pasid, true);
+ if (pte == NULL)
+ return -ENOMEM;
+
+ *pte = (cr3 & PAGE_MASK) | GCR3_VALID;
+
+ return __amd_iommu_flush_tlb(domain, pasid);
+}
+
+static int __clear_gcr3(struct protection_domain *domain, int pasid)
+{
+ u64 *pte;
+
+ if (domain->mode != PAGE_MODE_NONE)
+ return -EINVAL;
+
+ pte = __get_gcr3_pte(domain->gcr3_tbl, domain->glx, pasid, false);
+ if (pte == NULL)
+ return 0;
+
+ *pte = 0;
+
+ return __amd_iommu_flush_tlb(domain, pasid);
+}
+
+int amd_iommu_domain_set_gcr3(struct iommu_domain *dom, int pasid,
+ unsigned long cr3)
+{
+ struct protection_domain *domain = dom->priv;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&domain->lock, flags);
+ ret = __set_gcr3(domain, pasid, cr3);
+ spin_unlock_irqrestore(&domain->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(amd_iommu_domain_set_gcr3);
+
+int amd_iommu_domain_clear_gcr3(struct iommu_domain *dom, int pasid)
+{
+ struct protection_domain *domain = dom->priv;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&domain->lock, flags);
+ ret = __clear_gcr3(domain, pasid);
+ spin_unlock_irqrestore(&domain->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL(amd_iommu_domain_clear_gcr3);