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>

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 0ba078b..0852b70 100644 (file)
--- 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;
        }