iommu/amd: Remove the amd_iommu_domain_set_pt_root() and related

Looks like many refactorings here have left this confused. There is only
one storage of the root/mode, it is in the iop struct.

increase_address_space() calls amd_iommu_domain_set_pgtable() with values
that it already stored in iop a few lines above.

amd_iommu_domain_clr_pt_root() is zero'ing memory we are about to free. It
used to protect against a double free of root, but that is gone now.

Remove amd_iommu_domain_set_pgtable(), amd_iommu_domain_set_pt_root(),
amd_iommu_domain_clr_pt_root() as they are all pointless.

Reviewed-by: Vasant Hegde <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joerg Roedel <[email protected]>

Author: jgunthorpe

drivers/iommu/amd/amd_iommu.h

@@ -134,19 +134,6 @@ static inline void *iommu_phys_to_virt(unsigned long paddr)
 	return phys_to_virt(__sme_clr(paddr));
 }
 
-static inline
-void amd_iommu_domain_set_pt_root(struct protection_domain *domain, u64 root)
-{
-	domain->iop.root = (u64 *)(root & PAGE_MASK);
-	domain->iop.mode = root & 7; /* lowest 3 bits encode pgtable mode */
-}
-
-static inline
-void amd_iommu_domain_clr_pt_root(struct protection_domain *domain)
-{
-	amd_iommu_domain_set_pt_root(domain, 0);
-}
-
 static inline int get_pci_sbdf_id(struct pci_dev *pdev)
 {
 	int seg = pci_domain_nr(pdev->bus);

drivers/iommu/amd/io_pgtable.c

@@ -132,18 +132,6 @@ static void free_sub_pt(u64 *root, int mode, struct list_head *freelist)
 	}
 }
 
-void amd_iommu_domain_set_pgtable(struct protection_domain *domain,
-				  u64 *root, int mode)
-{
-	u64 pt_root;
-
-	/* lowest 3 bits encode pgtable mode */
-	pt_root = mode & 7;
-	pt_root |= (u64)root;
-
-	amd_iommu_domain_set_pt_root(domain, pt_root);
-}
-
 /*
  * This function is used to add another level to an IO page table. Adding
  * another level increases the size of the address space by 9 bits to a size up
@@ -176,12 +164,6 @@ static bool increase_address_space(struct protection_domain *domain,
 	domain->iop.mode += 1;
 	amd_iommu_update_and_flush_device_table(domain);
 
-	/*
-	 * Device Table needs to be updated and flushed before the new root can
-	 * be published.
-	 */
-	amd_iommu_domain_set_pgtable(domain, pte, domain->iop.mode);
-
 	pte = NULL;
 	ret = true;
 
@@ -560,23 +542,17 @@ static int iommu_v1_read_and_clear_dirty(struct io_pgtable_ops *ops,
 static void v1_free_pgtable(struct io_pgtable *iop)
 {
 	struct amd_io_pgtable *pgtable = container_of(iop, struct amd_io_pgtable, iop);
-	struct protection_domain *dom;
 	LIST_HEAD(freelist);
 
 	if (pgtable->mode == PAGE_MODE_NONE)
 		return;
 
-	dom = container_of(pgtable, struct protection_domain, iop);
-
 	/* Page-table is not visible to IOMMU anymore, so free it */
 	BUG_ON(pgtable->mode < PAGE_MODE_NONE ||
 	       pgtable->mode > PAGE_MODE_6_LEVEL);
 
 	free_sub_pt(pgtable->root, pgtable->mode, &freelist);
 	iommu_put_pages_list(&freelist);
-
-	/* Update data structure */
-	amd_iommu_domain_clr_pt_root(dom);
 }
 
 static struct io_pgtable *v1_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)