lkml.org 
[lkml]   [2015]   [May]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v11 08/10] iommu/vt-d: assign new page table for dma_map
Date
When a device driver issues the first dma_map command for a device, we
assign a new and empty page-table, thus removing all mappings from the
old kernel for the device.

Signed-off-by: Li, Zhen-Hua <zhen-hual@hp.com>
---
drivers/iommu/intel-iommu.c | 58 ++++++++++++++++++++++++++++++++++++++-------
1 file changed, 50 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 91545bf..3cc1027 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -396,6 +396,9 @@ static int copy_root_entry_table(struct intel_iommu *iommu);

static int intel_iommu_load_translation_tables(struct intel_iommu *iommu);

+static void unmap_device_dma(struct dmar_domain *domain,
+ struct device *dev,
+ struct intel_iommu *iommu);
static void iommu_check_pre_te_status(struct intel_iommu *iommu);
static u8 g_translation_pre_enabled;

@@ -3115,6 +3118,7 @@ static struct iova *intel_alloc_iova(struct device *dev,
static struct dmar_domain *__get_valid_domain_for_dev(struct device *dev)
{
struct dmar_domain *domain;
+ struct intel_iommu *iommu;
int ret;

domain = get_domain_for_dev(dev, DEFAULT_DOMAIN_ADDRESS_WIDTH);
@@ -3124,14 +3128,30 @@ static struct dmar_domain *__get_valid_domain_for_dev(struct device *dev)
return NULL;
}

- /* make sure context mapping is ok */
- if (unlikely(!domain_context_mapped(dev))) {
- ret = domain_context_mapping(domain, dev, CONTEXT_TT_MULTI_LEVEL);
- if (ret) {
- printk(KERN_ERR "Domain context map for %s failed",
- dev_name(dev));
- return NULL;
- }
+ /* if in kdump kernel, we need to unmap the mapped dma pages,
+ * detach this device first.
+ */
+ if (likely(domain_context_mapped(dev))) {
+ iommu = domain_get_iommu(domain);
+ if (iommu->pre_enabled_trans) {
+ unmap_device_dma(domain, dev, iommu);
+
+ domain = get_domain_for_dev(dev,
+ DEFAULT_DOMAIN_ADDRESS_WIDTH);
+ if (!domain) {
+ pr_err("Allocating domain for %s failed",
+ dev_name(dev));
+ return NULL;
+ }
+ } else
+ return domain;
+ }
+
+ ret = domain_context_mapping(domain, dev, CONTEXT_TT_MULTI_LEVEL);
+ if (ret) {
+ pr_err("Domain context map for %s failed",
+ dev_name(dev));
+ return NULL;
}

return domain;
@@ -5168,6 +5188,28 @@ static int intel_iommu_load_translation_tables(struct intel_iommu *iommu)
return ret;
}

+static void unmap_device_dma(struct dmar_domain *domain,
+ struct device *dev,
+ struct intel_iommu *iommu)
+{
+ struct context_entry *ce;
+ struct iova *iova;
+ phys_addr_t phys_addr;
+ dma_addr_t dev_addr;
+ struct pci_dev *pdev;
+
+ pdev = to_pci_dev(dev);
+ ce = iommu_context_addr(iommu, pdev->bus->number, pdev->devfn, 1);
+ phys_addr = context_address_root(ce) << VTD_PAGE_SHIFT;
+ dev_addr = phys_to_dma(dev, phys_addr);
+
+ iova = find_iova(&domain->iovad, IOVA_PFN(dev_addr));
+ if (iova)
+ intel_unmap(dev, dev_addr);
+
+ domain_remove_one_dev_info(domain, dev);
+}
+
static void iommu_check_pre_te_status(struct intel_iommu *iommu)
{
u32 sts;
--
2.0.0-rc0


\
 
 \ /
  Last update: 2015-05-11 12:21    [W:0.282 / U:20.176 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site