Re: [PATCH 3/8] iommu/vt-d: Remove IOVA handling code from non-dma_ops path

Could we merge patch 1-3 from this series? it just cleans up weird code and merging these patches will cover some of the work needed to move the intel iommu driver to the dma-iommu api in the future.

On Sat, 21 Dec 2019 at 07:04, Tom Murphy murphyt7@tcd.ie wrote:

Remove all IOVA handling code from the non-dma_ops path in the intel iommu driver.

There's no need for the non-dma_ops path to keep track of IOVAs. The whole point of the non-dma_ops path is that it allows the IOVAs to be handled separately. The IOVA handling code removed in this patch is pointless.

Signed-off-by: Tom Murphy murphyt7@tcd.ie

drivers/iommu/intel-iommu.c | 89 ++++++++++++++----------------------- 1 file changed, 33 insertions(+), 56 deletions(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 64b1a9793daa..8d72ea0fb843 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1908,7 +1908,8 @@ static void domain_exit(struct dmar_domain *domain) domain_remove_dev_info(domain);

    /* destroy iovas */

•   put_iova_domain(&domain->iovad);
  

•   if (domain->domain.type == IOMMU_DOMAIN_DMA)
  

•           put_iova_domain(&domain->iovad);
  
    if (domain->pgd) {
            struct page *freelist;
  

@@ -2671,19 +2672,9 @@ static struct dmar_domain *set_domain_for_dev(struct device *dev, }

static int iommu_domain_identity_map(struct dmar_domain *domain,

•                                unsigned long long start,
  

•                                unsigned long long end)
  

•                                unsigned long first_vpfn,
  

•                                unsigned long last_vpfn)
  

{

•   unsigned long first_vpfn = start >> VTD_PAGE_SHIFT;
  

•   unsigned long last_vpfn = end >> VTD_PAGE_SHIFT;
  

•   if (!reserve_iova(&domain->iovad, dma_to_mm_pfn(first_vpfn),
  

•                     dma_to_mm_pfn(last_vpfn))) {
  

•           pr_err("Reserving iova failed\n");
  

•           return -ENOMEM;
  

•   }
  

•   pr_debug("Mapping reserved region %llx-%llx\n", start, end);
    /*
     * RMRR range might have overlap with physical memory range,
     * clear it first
  

@@ -2760,7 +2751,8 @@ static int __init si_domain_init(int hw)

            for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
                    ret = iommu_domain_identity_map(si_domain,

•                                   PFN_PHYS(start_pfn), PFN_PHYS(end_pfn));
  

•                                   mm_to_dma_pfn(start_pfn),
  

•                                   mm_to_dma_pfn(end_pfn));
                    if (ret)
                            return ret;
            }
  

@@ -4593,58 +4585,37 @@ static int intel_iommu_memory_notifier(struct notifier_block *nb, unsigned long val, void *v) { struct memory_notify *mhp = v;

•   unsigned long long start, end;
  

•   unsigned long start_vpfn, last_vpfn;
  

•   unsigned long start_vpfn = mm_to_dma_pfn(mhp->start_pfn);
  

•   unsigned long last_vpfn = mm_to_dma_pfn(mhp->start_pfn +
  

•                   mhp->nr_pages - 1);
  
    switch (val) {
    case MEM_GOING_ONLINE:
  

•           start = mhp->start_pfn << PAGE_SHIFT;
  

•           end = ((mhp->start_pfn + mhp->nr_pages) << PAGE_SHIFT) - 1;
  

•           if (iommu_domain_identity_map(si_domain, start, end)) {
  

•                   pr_warn("Failed to build identity map for [%llx-%llx]\n",
  

•                           start, end);
  

•           if (iommu_domain_identity_map(si_domain, start_vpfn,
  

•                                   last_vpfn)) {
  

•                   pr_warn("Failed to build identity map for [%lx-%lx]\n",
  

•                           start_vpfn, last_vpfn);
                    return NOTIFY_BAD;
            }
            break;
  
    case MEM_OFFLINE:
    case MEM_CANCEL_ONLINE:
  

•           start_vpfn = mm_to_dma_pfn(mhp->start_pfn);
  

•           last_vpfn = mm_to_dma_pfn(mhp->start_pfn + mhp->nr_pages - 1);
  

•           while (start_vpfn <= last_vpfn) {
  

•                   struct iova *iova;
  

•           {
                    struct dmar_drhd_unit *drhd;
                    struct intel_iommu *iommu;
                    struct page *freelist;
  
  

•                   iova = find_iova(&si_domain->iovad, start_vpfn);
  

•                   if (iova == NULL) {
  

•                           pr_debug("Failed get IOVA for PFN %lx\n",
  

•                                    start_vpfn);
  

•                           break;
  

•                   }
  

•                   iova = split_and_remove_iova(&si_domain->iovad, iova,
  

•                                                start_vpfn, last_vpfn);
  

•                   if (iova == NULL) {
  

•                           pr_warn("Failed to split IOVA PFN [%lx-%lx]\n",
  

•                                   start_vpfn, last_vpfn);
  

•                           return NOTIFY_BAD;
  

•                   }
  

•                   freelist = domain_unmap(si_domain, iova->pfn_lo,
  

•                                          iova->pfn_hi);
  

•                   freelist = domain_unmap(si_domain, start_vpfn,
  

•                                   last_vpfn);
  
                    rcu_read_lock();
                    for_each_active_iommu(iommu, drhd)
                            iommu_flush_iotlb_psi(iommu, si_domain,
  

•                                   iova->pfn_lo, iova_size(iova),
  

•                                   start_vpfn, mhp->nr_pages,
                                    !freelist, 0);
                    rcu_read_unlock();
                    dma_free_pagelist(freelist);
  

•                   start_vpfn = iova->pfn_hi + 1;
  

•                   free_iova_mem(iova);
            }
            break;
    }
  

@@ -4672,8 +4643,9 @@ static void free_all_cpu_cached_iovas(unsigned int cpu) for (did = 0; did < cap_ndoms(iommu->cap); did++) { domain = get_iommu_domain(iommu, (u16)did);

•                   if (!domain)
  

•                   if (!domain || domain->domain.type != IOMMU_DOMAIN_DMA)
                            continue;
  

•                   free_cpu_cached_iovas(cpu, &domain->iovad);
            }
    }
  

@@ -5095,9 +5067,6 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width) { int adjust_width;

•   init_iova_domain(&domain->iovad, VTD_PAGE_SIZE, IOVA_START_PFN);
  

•   domain_reserve_special_ranges(domain);
  

•   /* calculate AGAW */
    domain->gaw = guest_width;
    adjust_width = guestwidth_to_adjustwidth(guest_width);
  

@@ -5116,6 +5085,18 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width) return 0; }

+static void intel_init_iova_domain(struct dmar_domain *dmar_domain) +{

•   init_iova_domain(&dmar_domain->iovad, VTD_PAGE_SIZE, IOVA_START_PFN);
  

•   copy_reserved_iova(&reserved_iova_list, &dmar_domain->iovad);
  

•   if (init_iova_flush_queue(&dmar_domain->iovad, iommu_flush_iova,
  

•                           iova_entry_free)) {
  

•           pr_warn("iova flush queue initialization failed\n");
  

•           intel_iommu_strict = 1;
  

•   }
  

+}

static struct iommu_domain *intel_iommu_domain_alloc(unsigned type) { struct dmar_domain *dmar_domain; @@ -5136,12 +5117,8 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type) return NULL; }

•           if (type == IOMMU_DOMAIN_DMA &&
  

•               init_iova_flush_queue(&dmar_domain->iovad,
  

•                                     iommu_flush_iova, iova_entry_free)) {
  

•                   pr_warn("iova flush queue initialization failed\n");
  

•                   intel_iommu_strict = 1;
  

•           }
  

•           if (type == IOMMU_DOMAIN_DMA)
  

•                   intel_init_iova_domain(dmar_domain);
  
            domain_update_iommu_cap(dmar_domain);
  
  

-- 2.20.1