intel-iommu: Don't free too much in dma_pte_free_pagetable()
[pandora-kernel.git] / drivers / pci / intel-iommu.c
index dfbabd1..35bdd2a 100644 (file)
@@ -62,9 +62,6 @@
 #define DMA_32BIT_PFN          IOVA_PFN(DMA_BIT_MASK(32))
 #define DMA_64BIT_PFN          IOVA_PFN(DMA_BIT_MASK(64))
 
-#ifndef PHYSICAL_PAGE_MASK
-#define PHYSICAL_PAGE_MASK PAGE_MASK
-#endif
 
 /* VT-d pages must always be _smaller_ than MM pages. Otherwise things
    are never going to work. */
@@ -764,34 +761,33 @@ static struct dma_pte *dma_pfn_level_pte(struct dmar_domain *domain,
        return NULL;
 }
 
-/* clear one page's page table */
-static void dma_pte_clear_one(struct dmar_domain *domain, unsigned long pfn)
-{
-       struct dma_pte *pte = NULL;
-
-       /* get last level pte */
-       pte = dma_pfn_level_pte(domain, pfn, 1);
-
-       if (pte) {
-               dma_clear_pte(pte);
-               domain_flush_cache(domain, pte, sizeof(*pte));
-       }
-}
-
 /* clear last level pte, a tlb flush should be followed */
 static void dma_pte_clear_range(struct dmar_domain *domain,
                                unsigned long start_pfn,
                                unsigned long last_pfn)
 {
        int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+       struct dma_pte *first_pte, *pte;
 
        BUG_ON(addr_width < BITS_PER_LONG && start_pfn >> addr_width);
        BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
 
        /* we don't need lock here; nobody else touches the iova range */
        while (start_pfn <= last_pfn) {
-               dma_pte_clear_one(domain, start_pfn);
-               start_pfn++;
+               first_pte = pte = dma_pfn_level_pte(domain, start_pfn, 1);
+               if (!pte) {
+                       start_pfn = align_to_level(start_pfn + 1, 2);
+                       continue;
+               }
+               while (start_pfn <= last_pfn &&
+                      (unsigned long)pte >> VTD_PAGE_SHIFT ==
+                      (unsigned long)first_pte >> VTD_PAGE_SHIFT) {
+                       dma_clear_pte(pte);
+                       start_pfn++;
+                       pte++;
+               }
+               domain_flush_cache(domain, first_pte,
+                                  (void *)pte - (void *)first_pte);
        }
 }
 
@@ -819,7 +815,7 @@ static void dma_pte_free_pagetable(struct dmar_domain *domain,
                if (tmp + level_size(level) - 1 > last_pfn)
                        return;
 
-               while (tmp <= last_pfn) {
+               while (tmp + level_size(level) - 1 <= last_pfn) {
                        pte = dma_pfn_level_pte(domain, tmp, level);
                        if (pte) {
                                free_pgtable_page(
@@ -1058,11 +1054,11 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
 }
 
 static void iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did,
-                                 u64 addr, unsigned int pages)
+                                 unsigned long pfn, unsigned int pages)
 {
        unsigned int mask = ilog2(__roundup_pow_of_two(pages));
+       uint64_t addr = (uint64_t)pfn << VTD_PAGE_SHIFT;
 
-       BUG_ON(addr & (~VTD_PAGE_MASK));
        BUG_ON(pages == 0);
 
        /*
@@ -1307,7 +1303,6 @@ static void dmar_init_reserved_ranges(void)
        struct pci_dev *pdev = NULL;
        struct iova *iova;
        int i;
-       u64 addr, size;
 
        init_iova_domain(&reserved_iova_list, DMA_32BIT_PFN);
 
@@ -1330,12 +1325,9 @@ static void dmar_init_reserved_ranges(void)
                        r = &pdev->resource[i];
                        if (!r->flags || !(r->flags & IORESOURCE_MEM))
                                continue;
-                       addr = r->start;
-                       addr &= PHYSICAL_PAGE_MASK;
-                       size = r->end - addr;
-                       size = PAGE_ALIGN(size);
-                       iova = reserve_iova(&reserved_iova_list, IOVA_PFN(addr),
-                               IOVA_PFN(size + addr) - 1);
+                       iova = reserve_iova(&reserved_iova_list,
+                                           IOVA_PFN(r->start),
+                                           IOVA_PFN(r->end));
                        if (!iova)
                                printk(KERN_ERR "Reserve iova failed\n");
                }
@@ -1643,42 +1635,86 @@ static int domain_context_mapped(struct pci_dev *pdev)
                                             tmp->devfn);
 }
 
-static int
-domain_page_mapping(struct dmar_domain *domain, dma_addr_t iova,
-                       u64 hpa, size_t size, int prot)
+static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+                           struct scatterlist *sg, unsigned long phys_pfn,
+                           unsigned long nr_pages, int prot)
 {
-       u64 start_pfn, end_pfn;
-       struct dma_pte *pte;
-       int index;
-       int addr_width = agaw_to_width(domain->agaw);
+       struct dma_pte *first_pte = NULL, *pte = NULL;
+       phys_addr_t uninitialized_var(pteval);
+       int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+       unsigned long sg_res;
 
-       BUG_ON(hpa >> addr_width);
+       BUG_ON(addr_width < BITS_PER_LONG && (iov_pfn + nr_pages - 1) >> addr_width);
 
        if ((prot & (DMA_PTE_READ|DMA_PTE_WRITE)) == 0)
                return -EINVAL;
-       iova &= PAGE_MASK;
-       start_pfn = ((u64)hpa) >> VTD_PAGE_SHIFT;
-       end_pfn = (VTD_PAGE_ALIGN(((u64)hpa) + size)) >> VTD_PAGE_SHIFT;
-       index = 0;
-       while (start_pfn < end_pfn) {
-               pte = pfn_to_dma_pte(domain, (iova >> VTD_PAGE_SHIFT) + index);
-               if (!pte)
-                       return -ENOMEM;
+
+       prot &= DMA_PTE_READ | DMA_PTE_WRITE | DMA_PTE_SNP;
+
+       if (sg)
+               sg_res = 0;
+       else {
+               sg_res = nr_pages + 1;
+               pteval = ((phys_addr_t)phys_pfn << VTD_PAGE_SHIFT) | prot;
+       }
+
+       while (nr_pages--) {
+               if (!sg_res) {
+                       sg_res = (sg->offset + sg->length + VTD_PAGE_SIZE - 1) >> VTD_PAGE_SHIFT;
+                       sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + sg->offset;
+                       sg->dma_length = sg->length;
+                       pteval = page_to_phys(sg_page(sg)) | prot;
+               }
+               if (!pte) {
+                       first_pte = pte = pfn_to_dma_pte(domain, iov_pfn);
+                       if (!pte)
+                               return -ENOMEM;
+               }
                /* We don't need lock here, nobody else
                 * touches the iova range
                 */
-               BUG_ON(dma_pte_addr(pte));
-               dma_set_pte_pfn(pte, start_pfn);
-               dma_set_pte_prot(pte, prot);
-               if (prot & DMA_PTE_SNP)
-                       dma_set_pte_snp(pte);
-               domain_flush_cache(domain, pte, sizeof(*pte));
-               start_pfn++;
-               index++;
+               if (unlikely(dma_pte_addr(pte))) {
+                       static int dumps = 5;
+                       printk(KERN_CRIT "ERROR: DMA PTE for vPFN 0x%lx already set (to %llx)\n",
+                              iov_pfn, pte->val);
+                       if (dumps) {
+                               dumps--;
+                               debug_dma_dump_mappings(NULL);
+                       }
+                       WARN_ON(1);
+               }
+               pte->val = pteval;
+               pte++;
+               if (!nr_pages ||
+                   (unsigned long)pte >> VTD_PAGE_SHIFT !=
+                   (unsigned long)first_pte >> VTD_PAGE_SHIFT) {
+                       domain_flush_cache(domain, first_pte,
+                                          (void *)pte - (void *)first_pte);
+                       pte = NULL;
+               }
+               iov_pfn++;
+               pteval += VTD_PAGE_SIZE;
+               sg_res--;
+               if (!sg_res)
+                       sg = sg_next(sg);
        }
        return 0;
 }
 
+static inline int domain_sg_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+                                   struct scatterlist *sg, unsigned long nr_pages,
+                                   int prot)
+{
+       return __domain_mapping(domain, iov_pfn, sg, 0, nr_pages, prot);
+}
+
+static inline int domain_pfn_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+                                    unsigned long phys_pfn, unsigned long nr_pages,
+                                    int prot)
+{
+       return __domain_mapping(domain, iov_pfn, NULL, phys_pfn, nr_pages, prot);
+}
+
 static void iommu_detach_dev(struct intel_iommu *iommu, u8 bus, u8 devfn)
 {
        if (!iommu)
@@ -1873,30 +1909,26 @@ static int iommu_domain_identity_map(struct dmar_domain *domain,
                                     unsigned long long start,
                                     unsigned long long end)
 {
-       unsigned long size;
-       unsigned long long base;
+       unsigned long first_vpfn = start >> VTD_PAGE_SHIFT;
+       unsigned long last_vpfn = end >> VTD_PAGE_SHIFT;
 
-       /* The address might not be aligned */
-       base = start & PAGE_MASK;
-       size = end - base;
-       size = PAGE_ALIGN(size);
-       if (!reserve_iova(&domain->iovad, IOVA_PFN(base),
-                       IOVA_PFN(base + size) - 1)) {
+       if (!reserve_iova(&domain->iovad, dma_to_mm_pfn(first_vpfn),
+                         dma_to_mm_pfn(last_vpfn))) {
                printk(KERN_ERR "IOMMU: reserve iova failed\n");
                return -ENOMEM;
        }
 
-       pr_debug("Mapping reserved region %lx@%llx for domain %d\n",
-                size, base, domain->id);
+       pr_debug("Mapping reserved region %llx-%llx for domain %d\n",
+                start, end, domain->id);
        /*
         * RMRR range might have overlap with physical memory range,
         * clear it first
         */
-       dma_pte_clear_range(domain, base >> VTD_PAGE_SHIFT,
-                           (base + size - 1) >> VTD_PAGE_SHIFT);
+       dma_pte_clear_range(domain, first_vpfn, last_vpfn);
 
-       return domain_page_mapping(domain, base, base, size,
-                                  DMA_PTE_READ|DMA_PTE_WRITE);
+       return domain_pfn_mapping(domain, first_vpfn, first_vpfn,
+                                 last_vpfn - first_vpfn + 1,
+                                 DMA_PTE_READ|DMA_PTE_WRITE);
 }
 
 static int iommu_prepare_identity_map(struct pci_dev *pdev,
@@ -2323,50 +2355,40 @@ error:
        return ret;
 }
 
-static inline u64 aligned_size(u64 host_addr, size_t size)
+static inline unsigned long aligned_nrpages(unsigned long host_addr,
+                                           size_t size)
 {
-       u64 addr;
-       addr = (host_addr & (~PAGE_MASK)) + size;
-       return PAGE_ALIGN(addr);
-}
-
-struct iova *
-iommu_alloc_iova(struct dmar_domain *domain, size_t size, u64 end)
-{
-       struct iova *piova;
-
-       /* Make sure it's in range */
-       end = min_t(u64, DOMAIN_MAX_ADDR(domain->gaw), end);
-       if (!size || (IOVA_START_ADDR + size > end))
-               return NULL;
+       host_addr &= ~PAGE_MASK;
+       host_addr += size + PAGE_SIZE - 1;
 
-       piova = alloc_iova(&domain->iovad,
-                       size >> PAGE_SHIFT, IOVA_PFN(end), 1);
-       return piova;
+       return host_addr >> VTD_PAGE_SHIFT;
 }
 
-static struct iova *
-__intel_alloc_iova(struct device *dev, struct dmar_domain *domain,
-                  size_t size, u64 dma_mask)
+static struct iova *intel_alloc_iova(struct device *dev,
+                                    struct dmar_domain *domain,
+                                    unsigned long nrpages, uint64_t dma_mask)
 {
        struct pci_dev *pdev = to_pci_dev(dev);
        struct iova *iova = NULL;
 
-       if (dma_mask <= DMA_BIT_MASK(32) || dmar_forcedac)
-               iova = iommu_alloc_iova(domain, size, dma_mask);
-       else {
+       /* Restrict dma_mask to the width that the iommu can handle */
+       dma_mask = min_t(uint64_t, DOMAIN_MAX_ADDR(domain->gaw), dma_mask);
+
+       if (!dmar_forcedac && dma_mask > DMA_BIT_MASK(32)) {
                /*
                 * First try to allocate an io virtual address in
                 * DMA_BIT_MASK(32) and if that fails then try allocating
                 * from higher range
                 */
-               iova = iommu_alloc_iova(domain, size, DMA_BIT_MASK(32));
-               if (!iova)
-                       iova = iommu_alloc_iova(domain, size, dma_mask);
-       }
-
-       if (!iova) {
-               printk(KERN_ERR"Allocating iova for %s failed", pci_name(pdev));
+               iova = alloc_iova(&domain->iovad, nrpages,
+                                 IOVA_PFN(DMA_BIT_MASK(32)), 1);
+               if (iova)
+                       return iova;
+       }
+       iova = alloc_iova(&domain->iovad, nrpages, IOVA_PFN(dma_mask), 1);
+       if (unlikely(!iova)) {
+               printk(KERN_ERR "Allocating %ld-page iova for %s failed",
+                      nrpages, pci_name(pdev));
                return NULL;
        }
 
@@ -2469,14 +2491,12 @@ static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
                return 0;
 
        iommu = domain_get_iommu(domain);
-       size = aligned_size((u64)paddr, size);
+       size = aligned_nrpages(paddr, size);
 
-       iova = __intel_alloc_iova(hwdev, domain, size, pdev->dma_mask);
+       iova = intel_alloc_iova(hwdev, domain, size, pdev->dma_mask);
        if (!iova)
                goto error;
 
-       start_paddr = (phys_addr_t)iova->pfn_lo << PAGE_SHIFT;
-
        /*
         * Check if DMAR supports zero-length reads on write only
         * mappings..
@@ -2492,20 +2512,20 @@ static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
         * might have two guest_addr mapping to the same host paddr, but this
         * is not a big problem
         */
-       ret = domain_page_mapping(domain, start_paddr,
-                                 ((u64)paddr) & PHYSICAL_PAGE_MASK,
-                                 size, prot);
+       ret = domain_pfn_mapping(domain, mm_to_dma_pfn(iova->pfn_lo),
+                                paddr >> VTD_PAGE_SHIFT, size, prot);
        if (ret)
                goto error;
 
        /* it's a non-present to present mapping. Only flush if caching mode */
        if (cap_caching_mode(iommu->cap))
-               iommu_flush_iotlb_psi(iommu, 0, start_paddr,
-                                     size >> VTD_PAGE_SHIFT);
+               iommu_flush_iotlb_psi(iommu, 0, mm_to_dma_pfn(iova->pfn_lo), size);
        else
                iommu_flush_write_buffer(iommu);
 
-       return start_paddr + ((u64)paddr & (~PAGE_MASK));
+       start_paddr = (phys_addr_t)iova->pfn_lo << PAGE_SHIFT;
+       start_paddr += paddr & ~PAGE_MASK;
+       return start_paddr;
 
 error:
        if (iova)
@@ -2627,8 +2647,7 @@ static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
        dma_pte_free_pagetable(domain, start_pfn, last_pfn);
 
        if (intel_iommu_strict) {
-               iommu_flush_iotlb_psi(iommu, domain->id,
-                                     start_pfn << VTD_PAGE_SHIFT,
+               iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
                                      last_pfn - start_pfn + 1);
                /* free iova */
                __free_iova(&domain->iovad, iova);
@@ -2714,8 +2733,7 @@ static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sglist,
        /* free page tables */
        dma_pte_free_pagetable(domain, start_pfn, last_pfn);
 
-       iommu_flush_iotlb_psi(iommu, domain->id,
-                             start_pfn << VTD_PAGE_SHIFT,
+       iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
                              (last_pfn - start_pfn + 1));
 
        /* free iova */
@@ -2739,17 +2757,16 @@ static int intel_nontranslate_map_sg(struct device *hddev,
 static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int nelems,
                        enum dma_data_direction dir, struct dma_attrs *attrs)
 {
-       phys_addr_t addr;
        int i;
        struct pci_dev *pdev = to_pci_dev(hwdev);
        struct dmar_domain *domain;
        size_t size = 0;
        int prot = 0;
-       size_t offset = 0;
+       size_t offset_pfn = 0;
        struct iova *iova = NULL;
        int ret;
        struct scatterlist *sg;
-       unsigned long start_addr;
+       unsigned long start_vpfn;
        struct intel_iommu *iommu;
 
        BUG_ON(dir == DMA_NONE);
@@ -2762,12 +2779,10 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int ne
 
        iommu = domain_get_iommu(domain);
 
-       for_each_sg(sglist, sg, nelems, i) {
-               addr = page_to_phys(sg_page(sg)) + sg->offset;
-               size += aligned_size((u64)addr, sg->length);
-       }
+       for_each_sg(sglist, sg, nelems, i)
+               size += aligned_nrpages(sg->offset, sg->length);
 
-       iova = __intel_alloc_iova(hwdev, domain, size, pdev->dma_mask);
+       iova = intel_alloc_iova(hwdev, domain, size, pdev->dma_mask);
        if (!iova) {
                sglist->dma_length = 0;
                return 0;
@@ -2783,36 +2798,24 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int ne
        if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
                prot |= DMA_PTE_WRITE;
 
-       start_addr = iova->pfn_lo << PAGE_SHIFT;
-       offset = 0;
-       for_each_sg(sglist, sg, nelems, i) {
-               addr = page_to_phys(sg_page(sg)) + sg->offset;
-               size = aligned_size((u64)addr, sg->length);
-               ret = domain_page_mapping(domain, start_addr + offset,
-                                         ((u64)addr) & PHYSICAL_PAGE_MASK,
-                                         size, prot);
-               if (ret) {
-                       /*  clear the page */
-                       dma_pte_clear_range(domain,
-                                           start_addr >> VTD_PAGE_SHIFT,
-                                           (start_addr + offset - 1) >> VTD_PAGE_SHIFT);
-                       /* free page tables */
-                       dma_pte_free_pagetable(domain, start_addr >> VTD_PAGE_SHIFT,
-                                              (start_addr + offset - 1) >> VTD_PAGE_SHIFT);
-                       /* free iova */
-                       __free_iova(&domain->iovad, iova);
-                       return 0;
-               }
-               sg->dma_address = start_addr + offset +
-                               ((u64)addr & (~PAGE_MASK));
-               sg->dma_length = sg->length;
-               offset += size;
+       start_vpfn = mm_to_dma_pfn(iova->pfn_lo);
+
+       ret = domain_sg_mapping(domain, start_vpfn, sglist, mm_to_dma_pfn(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;
        }
 
        /* it's a non-present to present mapping. Only flush if caching mode */
        if (cap_caching_mode(iommu->cap))
-               iommu_flush_iotlb_psi(iommu, 0, start_addr,
-                                     offset >> VTD_PAGE_SHIFT);
+               iommu_flush_iotlb_psi(iommu, 0, start_vpfn, offset_pfn);
        else
                iommu_flush_write_buffer(iommu);
 
@@ -3510,8 +3513,11 @@ static int intel_iommu_map_range(struct iommu_domain *domain,
                }
                dmar_domain->max_addr = max_addr;
        }
-
-       ret = domain_page_mapping(dmar_domain, iova, hpa, size, prot);
+       /* Round up size to next multiple of PAGE_SIZE, if it and
+          the low bits of hpa would take us onto the next page */
+       size = aligned_nrpages(hpa, size);
+       ret = domain_pfn_mapping(dmar_domain, iova >> VTD_PAGE_SHIFT,
+                                hpa >> VTD_PAGE_SHIFT, size, prot);
        return ret;
 }