Re: [PATCH v6 1/5] iommu/vt-d: Add debugfs support for Intel IOMMU internals

[Andy Shevchenko]

On Tue, 2018-01-09 at 19:48 -0800, Sohil Mehta wrote:
> From: Gayatri Kammela 
> 
> Enable Intel IOMMU debug to export Intel IOMMU internals in debugfs

 
> +config INTEL_IOMMU_DEBUG
> + bool "Export Intel IOMMU internals in DebugFS"
> + depends on INTEL_IOMMU && DEBUG_FS

> + default n

I thought I commented on this...

Please, remove. "n" is default default, so no need to duplicate it.

> + help
> +   IOMMU internal states such as context, PASID tables can be
> seen via
> +   debugfs. Select this option if you want to export these
> internals.
> +
> +   Say Y if you need this.

Also I lost a track how this option is being used here. It looks like
this part is not related to the patch itself.

-- 
Andy Shevchenko 
Intel Finland Oy
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[PATCH v6 1/5] iommu/vt-d: Add debugfs support for Intel IOMMU internals

[Sohil Mehta]

From: Gayatri Kammela 

Enable Intel IOMMU debug to export Intel IOMMU internals in debugfs

Cc: Sohil Mehta 
Cc: Fenghua Yu 
Cc: Ashok Raj 
Signed-off-by: Jacob Pan 
Signed-off-by: Gayatri Kammela 
---

v6: No change

v5: No change

v4: No change

v3: No change

v2: No change

 drivers/iommu/Kconfig   | 10 ++
 drivers/iommu/intel-iommu.c | 31 +++
 include/linux/intel-iommu.h | 32 
 include/linux/intel-svm.h   |  2 +-
 4 files changed, 46 insertions(+), 29 deletions(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index f3a2134..d7588ee 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -152,6 +152,16 @@ config INTEL_IOMMU
  and include PCI device scope covered by these DMA
  remapping devices.
 
+config INTEL_IOMMU_DEBUG
+   bool "Export Intel IOMMU internals in DebugFS"
+   depends on INTEL_IOMMU && DEBUG_FS
+   default n
+   help
+ IOMMU internal states such as context, PASID tables can be seen via
+ debugfs. Select this option if you want to export these internals.
+
+ Say Y if you need this.
+
 config INTEL_IOMMU_SVM
bool "Support for Shared Virtual Memory with Intel IOMMU"
depends on INTEL_IOMMU && X86
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 4a2de34..e05b8e0 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -183,16 +183,6 @@ static int rwbf_quirk;
 static int force_on = 0;
 int intel_iommu_tboot_noforce;
 
-/*
- * 0: Present
- * 1-11: Reserved
- * 12-63: Context Ptr (12 - (haw-1))
- * 64-127: Reserved
- */
-struct root_entry {
-   u64 lo;
-   u64 hi;
-};
 #define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry))
 
 /*
@@ -218,21 +208,6 @@ static phys_addr_t root_entry_uctp(struct root_entry *re)
 
return re->hi & VTD_PAGE_MASK;
 }
-/*
- * low 64 bits:
- * 0: present
- * 1: fault processing disable
- * 2-3: translation type
- * 12-63: address space root
- * high 64 bits:
- * 0-2: address width
- * 3-6: aval
- * 8-23: domain id
- */
-struct context_entry {
-   u64 lo;
-   u64 hi;
-};
 
 static inline void context_clear_pasid_enable(struct context_entry *context)
 {
@@ -259,7 +234,7 @@ static inline bool __context_present(struct context_entry 
*context)
return (context->lo & 1);
 }
 
-static inline bool context_present(struct context_entry *context)
+bool context_present(struct context_entry *context)
 {
return context_pasid_enabled(context) ?
 __context_present(context) :
@@ -819,7 +794,7 @@ static void domain_update_iommu_cap(struct dmar_domain 
*domain)
domain->iommu_superpage = domain_update_iommu_superpage(NULL);
 }
 
-static inline struct context_entry *iommu_context_addr(struct intel_iommu 
*iommu,
+struct context_entry *iommu_context_addr(struct intel_iommu *iommu,
   u8 bus, u8 devfn, int 
alloc)
 {
struct root_entry *root = >root_entry[bus];
@@ -5208,7 +5183,7 @@ static void intel_iommu_put_resv_regions(struct device 
*dev,
 
 #ifdef CONFIG_INTEL_IOMMU_SVM
 #define MAX_NR_PASID_BITS (20)
-static inline unsigned long intel_iommu_get_pts(struct intel_iommu *iommu)
+unsigned long intel_iommu_get_pts(struct intel_iommu *iommu)
 {
/*
 * Convert ecap_pss to extend context entry pts encoding, also
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index f3274d9..b8591dc 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -383,6 +383,33 @@ struct pasid_entry;
 struct pasid_state_entry;
 struct page_req_dsc;
 
+/*
+ * 0: Present
+ * 1-11: Reserved
+ * 12-63: Context Ptr (12 - (haw-1))
+ * 64-127: Reserved
+ */
+struct root_entry {
+   u64 lo;
+   u64 hi;
+};
+
+/*
+ * low 64 bits:
+ * 0: present
+ * 1: fault processing disable
+ * 2-3: translation type
+ * 12-63: address space root
+ * high 64 bits:
+ * 0-2: address width
+ * 3-6: aval
+ * 8-23: domain id
+ */
+struct context_entry {
+   u64 lo;
+   u64 hi;
+};
+
 struct intel_iommu {
void __iomem*reg; /* Pointer to hardware regs, virtual addr */
u64 reg_phys; /* physical address of hw register set */
@@ -488,8 +515,13 @@ struct intel_svm {
 
 extern int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct 
intel_svm_dev *sdev);
 extern struct intel_iommu *intel_svm_device_to_iommu(struct device *dev);
+extern unsigned long intel_iommu_get_pts(struct intel_iommu *iommu);
 #endif
 
 extern const struct attribute_group *intel_iommu_groups[];
+extern void intel_iommu_debugfs_init(void);
+extern bool context_present(struct context_entry *context);
+extern struct context_entry *iommu_context_addr(struct intel_iommu