iommu/amd: Move IO page table related functions

Preparing to migrate to use IO page table framework.
There is no functional change.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-7-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 2 insertions, 474 deletions

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 76e69c510db8..eda8e196fb14 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -138,8 +138,8 @@ static struct protection_domain *to_pdomain(struct iommu_domain *dom)
 	return container_of(dom, struct protection_domain, domain);
 }
 
-static void amd_iommu_domain_get_pgtable(struct protection_domain *domain,
-					 struct domain_pgtable *pgtable)
+void amd_iommu_domain_get_pgtable(struct protection_domain *domain,
+				  struct domain_pgtable *pgtable)
 {
 	u64 pt_root = atomic64_read(&domain->iop.pt_root);
 
@@ -147,18 +147,6 @@ static void amd_iommu_domain_get_pgtable(struct protection_domain *domain,
 	pgtable->mode = pt_root & 7; /* lowest 3 bits encode pgtable mode */
 }
 
-static 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);
-}
-
 static struct iommu_dev_data *alloc_dev_data(u16 devid)
 {
 	struct iommu_dev_data *dev_data;
@@ -414,29 +402,6 @@ static void amd_iommu_uninit_device(struct device *dev)
 	 */
 }
 
-/*
- * Helper function to get the first pte of a large mapping
- */
-static u64 *first_pte_l7(u64 *pte, unsigned long *page_size,
-			 unsigned long *count)
-{
-	unsigned long pte_mask, pg_size, cnt;
-	u64 *fpte;
-
-	pg_size  = PTE_PAGE_SIZE(*pte);
-	cnt      = PAGE_SIZE_PTE_COUNT(pg_size);
-	pte_mask = ~((cnt << 3) - 1);
-	fpte     = (u64 *)(((unsigned long)pte) & pte_mask);
-
-	if (page_size)
-		*page_size = pg_size;
-
-	if (count)
-		*count = cnt;
-
-	return fpte;
-}
-
 /****************************************************************************
  *
  * Interrupt handling functions
@@ -1361,443 +1326,6 @@ static void domain_flush_devices(struct protection_domain *domain)
 
 /****************************************************************************
  *
- * The functions below are used the create the page table mappings for
- * unity mapped regions.
- *
- ****************************************************************************/
-
-static void free_page_list(struct page *freelist)
-{
-	while (freelist != NULL) {
-		unsigned long p = (unsigned long)page_address(freelist);
-		freelist = freelist->freelist;
-		free_page(p);
-	}
-}
-
-static struct page *free_pt_page(unsigned long pt, struct page *freelist)
-{
-	struct page *p = virt_to_page((void *)pt);
-
-	p->freelist = freelist;
-
-	return p;
-}
-
-#define DEFINE_FREE_PT_FN(LVL, FN)						\
-static struct page *free_pt_##LVL (unsigned long __pt, struct page *freelist)	\
-{										\
-	unsigned long p;							\
-	u64 *pt;								\
-	int i;									\
-										\
-	pt = (u64 *)__pt;							\
-										\
-	for (i = 0; i < 512; ++i) {						\
-		/* PTE present? */						\
-		if (!IOMMU_PTE_PRESENT(pt[i]))					\
-			continue;						\
-										\
-		/* Large PTE? */						\
-		if (PM_PTE_LEVEL(pt[i]) == 0 ||					\
-		    PM_PTE_LEVEL(pt[i]) == 7)					\
-			continue;						\
-										\
-		p = (unsigned long)IOMMU_PTE_PAGE(pt[i]);			\
-		freelist = FN(p, freelist);					\
-	}									\
-										\
-	return free_pt_page((unsigned long)pt, freelist);			\
-}
-
-DEFINE_FREE_PT_FN(l2, free_pt_page)
-DEFINE_FREE_PT_FN(l3, free_pt_l2)
-DEFINE_FREE_PT_FN(l4, free_pt_l3)
-DEFINE_FREE_PT_FN(l5, free_pt_l4)
-DEFINE_FREE_PT_FN(l6, free_pt_l5)
-
-static struct page *free_sub_pt(unsigned long root, int mode,
-				struct page *freelist)
-{
-	switch (mode) {
-	case PAGE_MODE_NONE:
-	case PAGE_MODE_7_LEVEL:
-		break;
-	case PAGE_MODE_1_LEVEL:
-		freelist = free_pt_page(root, freelist);
-		break;
-	case PAGE_MODE_2_LEVEL:
-		freelist = free_pt_l2(root, freelist);
-		break;
-	case PAGE_MODE_3_LEVEL:
-		freelist = free_pt_l3(root, freelist);
-		break;
-	case PAGE_MODE_4_LEVEL:
-		freelist = free_pt_l4(root, freelist);
-		break;
-	case PAGE_MODE_5_LEVEL:
-		freelist = free_pt_l5(root, freelist);
-		break;
-	case PAGE_MODE_6_LEVEL:
-		freelist = free_pt_l6(root, freelist);
-		break;
-	default:
-		BUG();
-	}
-
-	return freelist;
-}
-
-static void free_pagetable(struct domain_pgtable *pgtable)
-{
-	struct page *freelist = NULL;
-	unsigned long root;
-
-	if (pgtable->mode == PAGE_MODE_NONE)
-		return;
-
-	BUG_ON(pgtable->mode < PAGE_MODE_NONE ||
-	       pgtable->mode > PAGE_MODE_6_LEVEL);
-
-	root = (unsigned long)pgtable->root;
-	freelist = free_sub_pt(root, pgtable->mode, freelist);
-
-	free_page_list(freelist);
-}
-
-/*
- * 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
- * to 64 bits.
- */
-static bool increase_address_space(struct protection_domain *domain,
-				   unsigned long address,
-				   gfp_t gfp)
-{
-	struct domain_pgtable pgtable;
-	unsigned long flags;
-	bool ret = true;
-	u64 *pte;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	amd_iommu_domain_get_pgtable(domain, &pgtable);
-
-	if (address <= PM_LEVEL_SIZE(pgtable.mode))
-		goto out;
-
-	ret = false;
-	if (WARN_ON_ONCE(pgtable.mode == PAGE_MODE_6_LEVEL))
-		goto out;
-
-	pte = (void *)get_zeroed_page(gfp);
-	if (!pte)
-		goto out;
-
-	*pte = PM_LEVEL_PDE(pgtable.mode, iommu_virt_to_phys(pgtable.root));
-
-	pgtable.root  = pte;
-	pgtable.mode += 1;
-	amd_iommu_update_and_flush_device_table(domain);
-	amd_iommu_domain_flush_complete(domain);
-
-	/*
-	 * Device Table needs to be updated and flushed before the new root can
-	 * be published.
-	 */
-	amd_iommu_domain_set_pgtable(domain, pte, pgtable.mode);
-
-	ret = true;
-
-out:
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-	return ret;
-}
-
-static u64 *alloc_pte(struct protection_domain *domain,
-		      unsigned long address,
-		      unsigned long page_size,
-		      u64 **pte_page,
-		      gfp_t gfp,
-		      bool *updated)
-{
-	struct domain_pgtable pgtable;
-	int level, end_lvl;
-	u64 *pte, *page;
-
-	BUG_ON(!is_power_of_2(page_size));
-
-	amd_iommu_domain_get_pgtable(domain, &pgtable);
-
-	while (address > PM_LEVEL_SIZE(pgtable.mode)) {
-		/*
-		 * Return an error if there is no memory to update the
-		 * page-table.
-		 */
-		if (!increase_address_space(domain, address, gfp))
-			return NULL;
-
-		/* Read new values to check if update was successful */
-		amd_iommu_domain_get_pgtable(domain, &pgtable);
-	}
-
-
-	level   = pgtable.mode - 1;
-	pte     = &pgtable.root[PM_LEVEL_INDEX(level, address)];
-	address = PAGE_SIZE_ALIGN(address, page_size);
-	end_lvl = PAGE_SIZE_LEVEL(page_size);
-
-	while (level > end_lvl) {
-		u64 __pte, __npte;
-		int pte_level;
-
-		__pte     = *pte;
-		pte_level = PM_PTE_LEVEL(__pte);
-
-		/*
-		 * If we replace a series of large PTEs, we need
-		 * to tear down all of them.
-		 */
-		if (IOMMU_PTE_PRESENT(__pte) &&
-		    pte_level == PAGE_MODE_7_LEVEL) {
-			unsigned long count, i;
-			u64 *lpte;
-
-			lpte = first_pte_l7(pte, NULL, &count);
-
-			/*
-			 * Unmap the replicated PTEs that still match the
-			 * original large mapping
-			 */
-			for (i = 0; i < count; ++i)
-				cmpxchg64(&lpte[i], __pte, 0ULL);
-
-			*updated = true;
-			continue;
-		}
-
-		if (!IOMMU_PTE_PRESENT(__pte) ||
-		    pte_level == PAGE_MODE_NONE) {
-			page = (u64 *)get_zeroed_page(gfp);
-
-			if (!page)
-				return NULL;
-
-			__npte = PM_LEVEL_PDE(level, iommu_virt_to_phys(page));
-
-			/* pte could have been changed somewhere. */
-			if (cmpxchg64(pte, __pte, __npte) != __pte)
-				free_page((unsigned long)page);
-			else if (IOMMU_PTE_PRESENT(__pte))
-				*updated = true;
-
-			continue;
-		}
-
-		/* No level skipping support yet */
-		if (pte_level != level)
-			return NULL;
-
-		level -= 1;
-
-		pte = IOMMU_PTE_PAGE(__pte);
-
-		if (pte_page && level == end_lvl)
-			*pte_page = pte;
-
-		pte = &pte[PM_LEVEL_INDEX(level, address)];
-	}
-
-	return pte;
-}
-
-/*
- * This function checks if there is a PTE for a given dma address. If
- * there is one, it returns the pointer to it.
- */
-static u64 *fetch_pte(struct protection_domain *domain,
-		      unsigned long address,
-		      unsigned long *page_size)
-{
-	struct domain_pgtable pgtable;
-	int level;
-	u64 *pte;
-
-	*page_size = 0;
-
-	amd_iommu_domain_get_pgtable(domain, &pgtable);
-
-	if (address > PM_LEVEL_SIZE(pgtable.mode))
-		return NULL;
-
-	level	   =  pgtable.mode - 1;
-	pte	   = &pgtable.root[PM_LEVEL_INDEX(level, address)];
-	*page_size =  PTE_LEVEL_PAGE_SIZE(level);
-
-	while (level > 0) {
-
-		/* Not Present */
-		if (!IOMMU_PTE_PRESENT(*pte))
-			return NULL;
-
-		/* Large PTE */
-		if (PM_PTE_LEVEL(*pte) == 7 ||
-		    PM_PTE_LEVEL(*pte) == 0)
-			break;
-
-		/* No level skipping support yet */
-		if (PM_PTE_LEVEL(*pte) != level)
-			return NULL;
-
-		level -= 1;
-
-		/* Walk to the next level */
-		pte	   = IOMMU_PTE_PAGE(*pte);
-		pte	   = &pte[PM_LEVEL_INDEX(level, address)];
-		*page_size = PTE_LEVEL_PAGE_SIZE(level);
-	}
-
-	/*
-	 * If we have a series of large PTEs, make
-	 * sure to return a pointer to the first one.
-	 */
-	if (PM_PTE_LEVEL(*pte) == PAGE_MODE_7_LEVEL)
-		pte = first_pte_l7(pte, page_size, NULL);
-
-	return pte;
-}
-
-static struct page *free_clear_pte(u64 *pte, u64 pteval, struct page *freelist)
-{
-	unsigned long pt;
-	int mode;
-
-	while (cmpxchg64(pte, pteval, 0) != pteval) {
-		pr_warn("AMD-Vi: IOMMU pte changed since we read it\n");
-		pteval = *pte;
-	}
-
-	if (!IOMMU_PTE_PRESENT(pteval))
-		return freelist;
-
-	pt   = (unsigned long)IOMMU_PTE_PAGE(pteval);
-	mode = IOMMU_PTE_MODE(pteval);
-
-	return free_sub_pt(pt, mode, freelist);
-}
-
-/*
- * Generic mapping functions. It maps a physical address into a DMA
- * address space. It allocates the page table pages if necessary.
- * In the future it can be extended to a generic mapping function
- * supporting all features of AMD IOMMU page tables like level skipping
- * and full 64 bit address spaces.
- */
-static int iommu_map_page(struct protection_domain *dom,
-			  unsigned long bus_addr,
-			  unsigned long phys_addr,
-			  unsigned long page_size,
-			  int prot,
-			  gfp_t gfp)
-{
-	struct page *freelist = NULL;
-	bool updated = false;
-	u64 __pte, *pte;
-	int ret, i, count;
-
-	BUG_ON(!IS_ALIGNED(bus_addr, page_size));
-	BUG_ON(!IS_ALIGNED(phys_addr, page_size));
-
-	ret = -EINVAL;
-	if (!(prot & IOMMU_PROT_MASK))
-		goto out;
-
-	count = PAGE_SIZE_PTE_COUNT(page_size);
-	pte   = alloc_pte(dom, bus_addr, page_size, NULL, gfp, &updated);
-
-	ret = -ENOMEM;
-	if (!pte)
-		goto out;
-
-	for (i = 0; i < count; ++i)
-		freelist = free_clear_pte(&pte[i], pte[i], freelist);
-
-	if (freelist != NULL)
-		updated = true;
-
-	if (count > 1) {
-		__pte = PAGE_SIZE_PTE(__sme_set(phys_addr), page_size);
-		__pte |= PM_LEVEL_ENC(7) | IOMMU_PTE_PR | IOMMU_PTE_FC;
-	} else
-		__pte = __sme_set(phys_addr) | IOMMU_PTE_PR | IOMMU_PTE_FC;
-
-	if (prot & IOMMU_PROT_IR)
-		__pte |= IOMMU_PTE_IR;
-	if (prot & IOMMU_PROT_IW)
-		__pte |= IOMMU_PTE_IW;
-
-	for (i = 0; i < count; ++i)
-		pte[i] = __pte;
-
-	ret = 0;
-
-out:
-	if (updated) {
-		unsigned long flags;
-
-		spin_lock_irqsave(&dom->lock, flags);
-		/*
-		 * Flush domain TLB(s) and wait for completion. Any Device-Table
-		 * Updates and flushing already happened in
-		 * increase_address_space().
-		 */
-		amd_iommu_domain_flush_tlb_pde(dom);
-		amd_iommu_domain_flush_complete(dom);
-		spin_unlock_irqrestore(&dom->lock, flags);
-	}
-
-	/* Everything flushed out, free pages now */
-	free_page_list(freelist);
-
-	return ret;
-}
-
-static unsigned long iommu_unmap_page(struct protection_domain *dom,
-				      unsigned long bus_addr,
-				      unsigned long page_size)
-{
-	unsigned long long unmapped;
-	unsigned long unmap_size;
-	u64 *pte;
-
-	BUG_ON(!is_power_of_2(page_size));
-
-	unmapped = 0;
-
-	while (unmapped < page_size) {
-
-		pte = fetch_pte(dom, bus_addr, &unmap_size);
-
-		if (pte) {
-			int i, count;
-
-			count = PAGE_SIZE_PTE_COUNT(unmap_size);
-			for (i = 0; i < count; i++)
-				pte[i] = 0ULL;
-		}
-
-		bus_addr  = (bus_addr & ~(unmap_size - 1)) + unmap_size;
-		unmapped += unmap_size;
-	}
-
-	BUG_ON(unmapped && !is_power_of_2(unmapped));
-
-	return unmapped;
-}
-
-/****************************************************************************
- *
  * The next functions belong to the domain allocation. A domain is
  * allocated for every IOMMU as the default domain. If device isolation
  * is enabled, every device get its own domain. The most important thing