[PATCH 16/17] iommu/vt-d: Copy old irte in intel_setup_irq_remapping

[Joerg Roedel]

From: Joerg Roedel <jroe...@suse.de>

Copy over the old irq remapping table in the
intel_setup_irq_remapping function. The reason is that
intel_enable_irq_remapping runs with irqs disabled and thus
we can not safely call ioremap. Therefore we need to copy in
the prepare stage when irqs are still enabled.

Tested-by: Baoquan He <b...@redhat.com>
Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
 drivers/iommu/intel_irq_remapping.c | 40 ++++++++++++++++++++-----------------
 1 file changed, 22 insertions(+), 18 deletions(-)

diff --git a/drivers/iommu/intel_irq_remapping.c 
b/drivers/iommu/intel_irq_remapping.c
index f7b02ca..07a8e82 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -24,6 +24,7 @@
 static int iommu_load_old_irte(struct intel_iommu *iommu);
 static int __iommu_update_old_irte(struct intel_iommu *iommu, int index);
 static void iommu_check_pre_ir_status(struct intel_iommu *iommu);
+static void iommu_disable_irq_remapping(struct intel_iommu *iommu);
 
 struct ioapic_scope {
        struct intel_iommu *iommu;
@@ -538,6 +539,26 @@ static int intel_setup_irq_remapping(struct intel_iommu 
*iommu)
                }
        }
 
+       iommu_check_pre_ir_status(iommu);
+
+       if (!is_kdump_kernel() && iommu->pre_enabled_ir) {
+               iommu_disable_irq_remapping(iommu);
+               iommu->pre_enabled_ir = 0;
+               pr_warn("IRQ remapping was enabled on %s but we are not in 
kdump mode\n",
+                               iommu->name);
+       }
+
+       if (iommu->pre_enabled_ir) {
+               if (iommu_load_old_irte(iommu))
+                       pr_err("Failed to copy IR table for %s from previous 
kernel\n",
+                              iommu->name);
+               else
+                       pr_info("Copied IR table for %s from previous kernel\n",
+                               iommu->name);
+       }
+
+       iommu_set_irq_remapping(iommu, eim_mode);
+
        return 0;
 
 out_free_pages:
@@ -682,28 +703,11 @@ static int __init intel_enable_irq_remapping(void)
        struct intel_iommu *iommu;
        bool setup = false;
 
-       for_each_iommu(iommu, drhd) {
-               iommu_check_pre_ir_status(iommu);
-
-               if (!is_kdump_kernel() && iommu->pre_enabled_ir) {
-                       iommu_disable_irq_remapping(iommu);
-                       iommu->pre_enabled_ir = 0;
-                       pr_warn("IRQ remapping was enabled on %s but we are not 
in kdump mode\n",
-                               iommu->name);
-               }
-       }
-
        /*
         * Setup Interrupt-remapping for all the DRHD's now.
         */
        for_each_iommu(iommu, drhd) {
-               if (iommu->pre_enabled_ir) {
-                       iommu_load_old_irte(iommu);
-               } else {
-                       iommu_set_irq_remapping(iommu, eim_mode);
-                       iommu_enable_irq_remapping(iommu);
-               }
-
+               iommu_enable_irq_remapping(iommu);
                setup = true;
        }
 
-- 
1.9.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu