[PATCH 2/6] iommu/vt-d: Add Intel IOMMU debugfs to show context internals

[Sohil Mehta]

From: Gayatri Kammela 

IOMMU internals states such as root and context can be exported to the
userspace.

Example of such dump in Kabylake:

root@OTC-KBLH-01:~# cat /sys/kernel/debug/intel_iommu/intel_iommu_ctx

IOMMU dmar2:Root Table Addr:4558a3000
 Root tbl entries:
Bus 0 L: 4558aa001 H: 0
 Context table entries for Bus: 0
[entry] DID :B :D .FLow High
[160]   :00:14.00   4558a9001   102
[184]   :00:17.00   400eac001   302
[248]   :00:1f.00   4558af001   202
[251]   :00:1f.03   40070e001   502
[254]   :00:1f.06   4467c9001   602
 Root tbl entries:
Bus 1 L: 3fc8c2001 H: 0
 Context table entries for Bus: 1
[entry] DID :B :D .FLow High
[0] :01:00.00   3fc8c3001   402

Cc: Sohil Mehta 
Cc: Fenghua Yu 
Cc: Ashok Raj 
Signed-off-by: Jacob Pan 
Signed-off-by: Gayatri Kammela 
---
 drivers/iommu/Makefile|   1 +
 drivers/iommu/intel-iommu-debug.c | 149 ++
 drivers/iommu/intel-iommu.c   |   4 +
 3 files changed, 154 insertions(+)
 create mode 100644 drivers/iommu/intel-iommu-debug.c

diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index b910aea..3631884 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_ARM_SMMU) += arm-smmu.o
 obj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o
 obj-$(CONFIG_DMAR_TABLE) += dmar.o
 obj-$(CONFIG_INTEL_IOMMU) += intel-iommu.o
+obj-$(CONFIG_INTEL_IOMMU_DEBUG) += intel-iommu-debug.o
 obj-$(CONFIG_INTEL_IOMMU_SVM) += intel-svm.o
 obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
 obj-$(CONFIG_IRQ_REMAP) += intel_irq_remapping.o irq_remapping.o
diff --git a/drivers/iommu/intel-iommu-debug.c 
b/drivers/iommu/intel-iommu-debug.c
new file mode 100644
index 000..90872ed
--- /dev/null
+++ b/drivers/iommu/intel-iommu-debug.c
@@ -0,0 +1,149 @@
+/*
+ * Copyright © 2017 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * Authors: Gayatri Kammela 
+ *  Jacob Pan 
+ *
+ */
+
+#define pr_fmt(fmt) "INTEL_IOMMU: " fmt
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include "irq_remapping.h"
+
+#define TOTAL_BUS_NR (256) /* full bus range 256 */
+
+static void ctx_tbl_entry_show(struct seq_file *m, void *unused,
+  struct intel_iommu *iommu, int bus, bool ext,
+  bool new_ext)
+{
+   struct context_entry *context;
+   int ctx;
+   unsigned long flags;
+
+   seq_printf(m, "%s Context table entries for Bus: %d\n",
+  ext ? "Lower" : "", bus);
+   seq_printf(m, "[entry]\tDID :B :D .F\tLow\t\tHigh\n");
+
+   spin_lock_irqsave(>lock, flags);
+
+   /* Publish either context entries or extended contenxt entries */
+   for (ctx = 0; ctx < (ext ? 128 : 256); ctx++) {
+   context = iommu_context_addr(iommu, bus, ctx, 0);
+   if (!context)
+   goto out;
+   if (context_present(context)) {
+   seq_printf(m, "[%d]\t%04x:%02x:%02x.%02x\t%llx\t%llx\n",
+  ctx, iommu->segment, bus, PCI_SLOT(ctx),
+  PCI_FUNC(ctx), context[0].lo, context[0].hi);
+   }
+   }
+out:
+   spin_unlock_irqrestore(>lock, flags);
+}
+
+static void root_tbl_entry_show(struct seq_file *m, void *unused,
+   struct intel_iommu *iommu, u64 rtaddr_reg,
+   bool ext, bool new_ext)
+{
+   int bus;
+
+   seq_printf(m, "\nIOMMU %s: %2s Root Table Addr:%llx\n", iommu->name,
+  ext ? "Extended" : "", rtaddr_reg);
+   /* Publish extended root table entries or root table entries here */
+   for (bus = 0; bus < TOTAL_BUS_NR; bus++) {
+   if (!iommu->root_entry[bus].lo)
+   continue;
+
+   seq_printf(m, "%s Root tbl entries:\n", ext ? "Extended" : "");
+   seq_printf(m, "Bus %d L: %llx H: %llx\n", bus,
+  iommu->root_entry[bus].lo, iommu->root_entry[bus].hi
+ );
+
+   ctx_tbl_entry_show(m, unused, iommu, bus, ext, new_ext);
+   }
+}
+
+static int intel_iommu_debug_show(struct seq_file 

[PATCH 2/6] iommu/vt-d: Add Intel IOMMU debugfs to show context internals

[Sohil Mehta]

From: Gayatri Kammela 

IOMMU internals states such as root and context can be exported to the
userspace.

Example of such dump in Kabylake:

root@OTC-KBLH-01:~# cat /sys/kernel/debug/intel_iommu/intel_iommu_ctx

IOMMU dmar2:Root Table Addr:4558a3000
 Root tbl entries:
Bus 0 L: 4558aa001 H: 0
 Context table entries for Bus: 0
[entry] DID :B :D .FLow High
[160]   :00:14.00   4558a9001   102
[184]   :00:17.00   400eac001   302
[248]   :00:1f.00   4558af001   202
[251]   :00:1f.03   40070e001   502
[254]   :00:1f.06   4467c9001   602
 Root tbl entries:
Bus 1 L: 3fc8c2001 H: 0
 Context table entries for Bus: 1
[entry] DID :B :D .FLow High
[0] :01:00.00   3fc8c3001   402

Cc: Sohil Mehta 
Cc: Fenghua Yu 
Cc: Ashok Raj 
Signed-off-by: Jacob Pan 
Signed-off-by: Gayatri Kammela 
---
 drivers/iommu/Makefile|   1 +
 drivers/iommu/intel-iommu-debug.c | 149 ++
 drivers/iommu/intel-iommu.c   |   4 +
 3 files changed, 154 insertions(+)
 create mode 100644 drivers/iommu/intel-iommu-debug.c

diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index b910aea..3631884 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_ARM_SMMU) += arm-smmu.o
 obj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o
 obj-$(CONFIG_DMAR_TABLE) += dmar.o
 obj-$(CONFIG_INTEL_IOMMU) += intel-iommu.o
+obj-$(CONFIG_INTEL_IOMMU_DEBUG) += intel-iommu-debug.o
 obj-$(CONFIG_INTEL_IOMMU_SVM) += intel-svm.o
 obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
 obj-$(CONFIG_IRQ_REMAP) += intel_irq_remapping.o irq_remapping.o
diff --git a/drivers/iommu/intel-iommu-debug.c 
b/drivers/iommu/intel-iommu-debug.c
new file mode 100644
index 000..90872ed
--- /dev/null
+++ b/drivers/iommu/intel-iommu-debug.c
@@ -0,0 +1,149 @@
+/*
+ * Copyright © 2017 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * Authors: Gayatri Kammela 
+ *  Jacob Pan 
+ *
+ */
+
+#define pr_fmt(fmt) "INTEL_IOMMU: " fmt
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include "irq_remapping.h"
+
+#define TOTAL_BUS_NR (256) /* full bus range 256 */
+
+static void ctx_tbl_entry_show(struct seq_file *m, void *unused,
+  struct intel_iommu *iommu, int bus, bool ext,
+  bool new_ext)
+{
+   struct context_entry *context;
+   int ctx;
+   unsigned long flags;
+
+   seq_printf(m, "%s Context table entries for Bus: %d\n",
+  ext ? "Lower" : "", bus);
+   seq_printf(m, "[entry]\tDID :B :D .F\tLow\t\tHigh\n");
+
+   spin_lock_irqsave(>lock, flags);
+
+   /* Publish either context entries or extended contenxt entries */
+   for (ctx = 0; ctx < (ext ? 128 : 256); ctx++) {
+   context = iommu_context_addr(iommu, bus, ctx, 0);
+   if (!context)
+   goto out;
+   if (context_present(context)) {
+   seq_printf(m, "[%d]\t%04x:%02x:%02x.%02x\t%llx\t%llx\n",
+  ctx, iommu->segment, bus, PCI_SLOT(ctx),
+  PCI_FUNC(ctx), context[0].lo, context[0].hi);
+   }
+   }
+out:
+   spin_unlock_irqrestore(>lock, flags);
+}
+
+static void root_tbl_entry_show(struct seq_file *m, void *unused,
+   struct intel_iommu *iommu, u64 rtaddr_reg,
+   bool ext, bool new_ext)
+{
+   int bus;
+
+   seq_printf(m, "\nIOMMU %s: %2s Root Table Addr:%llx\n", iommu->name,
+  ext ? "Extended" : "", rtaddr_reg);
+   /* Publish extended root table entries or root table entries here */
+   for (bus = 0; bus < TOTAL_BUS_NR; bus++) {
+   if (!iommu->root_entry[bus].lo)
+   continue;
+
+   seq_printf(m, "%s Root tbl entries:\n", ext ? "Extended" : "");
+   seq_printf(m, "Bus %d L: %llx H: %llx\n", bus,
+  iommu->root_entry[bus].lo, iommu->root_entry[bus].hi
+ );
+
+   ctx_tbl_entry_show(m, unused, iommu, bus, ext, new_ext);
+   }
+}
+
+static int intel_iommu_debug_show(struct seq_file *m, void *unused)
+{
+   struct dmar_drhd_unit *drhd;
+   struct intel_iommu *iommu;
+   u64 rtaddr_reg;
+   bool new_ext, ext;
+
+   rcu_read_lock();
+   for_each_active_iommu(iommu,