iommu/vt-d: Simplify intel_unmap_sg() and kill duplicated code

Introduce intel_unmap() to reduce duplicated code in intel_unmap_sg()
and intel_unmap_page().

Also let dma_pte_free_pagetable() to call dma_pte_clear_range() directly,
so caller only needs to call dma_pte_free_pagetable().

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 19 insertions, 51 deletions

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 0ba078bc0f32..0852b7021e4a 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -984,6 +984,8 @@ static void dma_pte_free_pagetable(struct dmar_domain *domain,
         BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
         BUG_ON(start_pfn > last_pfn);
 
+        dma_pte_clear_range(domain, start_pfn, last_pfn);
+
         /* We don't need lock here; nobody else touches the iova range */
         dma_pte_free_level(domain, agaw_to_level(domain->agaw),
                            domain->pgd, 0, start_pfn, last_pfn);
@@ -2011,12 +2013,14 @@ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
                         /* It is large page*/
                         if (largepage_lvl > 1) {
                                 pteval |= DMA_PTE_LARGE_PAGE;
-                                /* Ensure that old small page tables are removed to make room
-                                   for superpage, if they exist. */
-                                dma_pte_clear_range(domain, iov_pfn,
-                                                    iov_pfn + lvl_to_nr_pages(largepage_lvl) - 1);
+                                lvl_pages = lvl_to_nr_pages(largepage_lvl);
+                                /*
+                                 * Ensure that old small page tables are
+                                 * removed to make room for superpage,
+                                 * if they exist.
+                                 */
                                 dma_pte_free_pagetable(domain, iov_pfn,
-                                                       iov_pfn + lvl_to_nr_pages(largepage_lvl) - 1);
+                                                       iov_pfn + lvl_pages - 1);
                         } else {
                                 pteval &= ~(uint64_t)DMA_PTE_LARGE_PAGE;
                         }
@@ -3148,9 +3152,7 @@ static void add_unmap(struct dmar_domain *dom, struct iova *iova, struct page *f
         spin_unlock_irqrestore(&async_umap_flush_lock, flags);
 }
 
-static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
-                             size_t size, enum dma_data_direction dir,
-                             struct dma_attrs *attrs)
+static void intel_unmap(struct device *dev, dma_addr_t dev_addr)
 {
         struct dmar_domain *domain;
         unsigned long start_pfn, last_pfn;
@@ -3194,6 +3196,13 @@ static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
         }
 }
 
+static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
+                             size_t size, enum dma_data_direction dir,
+                             struct dma_attrs *attrs)
+{
+        intel_unmap(dev, dev_addr);
+}
+
 static void *intel_alloc_coherent(struct device *dev, size_t size,
                                   dma_addr_t *dma_handle, gfp_t flags,
                                   struct dma_attrs *attrs)
@@ -3250,7 +3259,7 @@ static void intel_free_coherent(struct device *dev, size_t size, void *vaddr,
         size = PAGE_ALIGN(size);
         order = get_order(size);
 
-        intel_unmap_page(dev, dma_handle, size, DMA_BIDIRECTIONAL, NULL);
+        intel_unmap(dev, dma_handle);
         if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
                 __free_pages(page, order);
 }
@@ -3259,43 +3268,7 @@ static void intel_unmap_sg(struct device *dev, struct scatterlist *sglist,
                            int nelems, enum dma_data_direction dir,
                            struct dma_attrs *attrs)
 {
-        struct dmar_domain *domain;
-        unsigned long start_pfn, last_pfn;
-        struct iova *iova;
-        struct intel_iommu *iommu;
-        struct page *freelist;
-
-        if (iommu_no_mapping(dev))
-                return;
-
-        domain = find_domain(dev);
-        BUG_ON(!domain);
-
-        iommu = domain_get_iommu(domain);
-
-        iova = find_iova(&domain->iovad, IOVA_PFN(sglist[0].dma_address));
-        if (WARN_ONCE(!iova, "Driver unmaps unmatched sglist at PFN %llx\n",
-                      (unsigned long long)sglist[0].dma_address))
-                return;
-
-        start_pfn = mm_to_dma_pfn(iova->pfn_lo);
-        last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
-
-        freelist = domain_unmap(domain, start_pfn, last_pfn);
-
-        if (intel_iommu_strict) {
-                iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
-                                      last_pfn - start_pfn + 1, !freelist, 0);
-                /* free iova */
-                __free_iova(&domain->iovad, iova);
-                dma_free_pagelist(freelist);
-        } else {
-                add_unmap(domain, iova, freelist);
-                /*
-                 * queue up the release of the unmap to save the 1/6th of the
-                 * cpu used up by the iotlb flush operation...
-                 */
-        }
+        intel_unmap(dev, sglist[0].dma_address);
 }
 
 static int intel_nontranslate_map_sg(struct device *hddev,
@@ -3359,13 +3332,8 @@ static int intel_map_sg(struct device *dev, struct scatterlist *sglist, int nele
 
         ret = domain_sg_mapping(domain, start_vpfn, sglist, size, prot);
         if (unlikely(ret)) {
-                /*  clear the page */
-                dma_pte_clear_range(domain, start_vpfn,
-                                    start_vpfn + size - 1);
-                /* free page tables */
                 dma_pte_free_pagetable(domain, start_vpfn,
                                        start_vpfn + size - 1);
-                /* free iova */
                 __free_iova(&domain->iovad, iova);
                 return 0;
         }