diff mbox

[PATCHv6,2/8] dma-debug: add support for resource mappings

Message ID 1462812247-3414-3-git-send-email-niklas.soderlund+renesas@ragnatech.se (mailing list archive)
State New, archived
Headers show

Commit Message

Niklas Söderlund May 9, 2016, 4:44 p.m. UTC
A MMIO mapped resource can not be represented by a struct page so a new
debug type is needed to handle this. This patch add such type and
functionality to add/remove entries and how to translate them to a
physical address.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
 include/linux/dma-debug.h | 19 +++++++++++++++++
 lib/dma-debug.c           | 52 +++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 69 insertions(+), 2 deletions(-)

Comments

Konrad Rzeszutek Wilk May 17, 2016, 2:50 p.m. UTC | #1
> +void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
> +			    int direction, dma_addr_t dma_addr)
> +{
> +	struct dma_debug_entry *entry;
> +
> +	if (unlikely(dma_debug_disabled()))
> +		return;
> +
> +	entry = dma_entry_alloc();
> +	if (!entry)
> +		return;
> +
> +	entry->type		= dma_debug_resource;
> +	entry->dev		= dev;
> +	entry->pfn		= __phys_to_pfn(addr);
> +	entry->offset		= addr - PHYS_PFN(entry->pfn);

Is that right? 

__phys_to_pfn(addr) is PHYS_PFN(addr), so what you get here is

addr - PHYS_PFN(PHYS_PFN(addr)) ?


> +	entry->size		= size;
> +	entry->dev_addr		= dma_addr;
> +	entry->direction	= direction;
> +	entry->map_err_type	= MAP_ERR_NOT_CHECKED;
> +
> +	add_dma_entry(entry);
> +}
> +EXPORT_SYMBOL(debug_dma_map_resource);
> +
Niklas Söderlund May 19, 2016, 11:21 a.m. UTC | #2
Hi Konrad,

Thanks for your feedback.

On 2016-05-17 10:50:02 -0400, Konrad Rzeszutek Wilk wrote:
> > +void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
> > +			    int direction, dma_addr_t dma_addr)
> > +{
> > +	struct dma_debug_entry *entry;
> > +
> > +	if (unlikely(dma_debug_disabled()))
> > +		return;
> > +
> > +	entry = dma_entry_alloc();
> > +	if (!entry)
> > +		return;
> > +
> > +	entry->type		= dma_debug_resource;
> > +	entry->dev		= dev;
> > +	entry->pfn		= __phys_to_pfn(addr);
> > +	entry->offset		= addr - PHYS_PFN(entry->pfn);
> 
> Is that right? 

You are correct that should be:

   entry->offset = addr - PFN_PHYS(entry->pfn);

Or even better:

   entry->offset = addr - __pfn_to_phys(entry->pfn);

I will address this and resend late next week, still hoping for some 
more feedback.

> 
> __phys_to_pfn(addr) is PHYS_PFN(addr), so what you get here is
> 
> addr - PHYS_PFN(PHYS_PFN(addr)) ?
> 
> 
> > +	entry->size		= size;
> > +	entry->dev_addr		= dma_addr;
> > +	entry->direction	= direction;
> > +	entry->map_err_type	= MAP_ERR_NOT_CHECKED;
> > +
> > +	add_dma_entry(entry);
> > +}
> > +EXPORT_SYMBOL(debug_dma_map_resource);
> > +
Robin Murphy May 19, 2016, 11:42 a.m. UTC | #3
On 19/05/16 12:21, Niklas Söderlund wrote:
> Hi Konrad,
>
> Thanks for your feedback.
>
> On 2016-05-17 10:50:02 -0400, Konrad Rzeszutek Wilk wrote:
>>> +void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
>>> +			    int direction, dma_addr_t dma_addr)
>>> +{
>>> +	struct dma_debug_entry *entry;
>>> +
>>> +	if (unlikely(dma_debug_disabled()))
>>> +		return;
>>> +
>>> +	entry = dma_entry_alloc();
>>> +	if (!entry)
>>> +		return;
>>> +
>>> +	entry->type		= dma_debug_resource;
>>> +	entry->dev		= dev;
>>> +	entry->pfn		= __phys_to_pfn(addr);
>>> +	entry->offset		= addr - PHYS_PFN(entry->pfn);
>>
>> Is that right?
>
> You are correct that should be:
>
>     entry->offset = addr - PFN_PHYS(entry->pfn);
>
> Or even better:
>
>     entry->offset = addr - __pfn_to_phys(entry->pfn);

Better still, simply offset_in_page(addr) (as per dma_map_single()).

Robin.

> I will address this and resend late next week, still hoping for some
> more feedback.
>
>>
>> __phys_to_pfn(addr) is PHYS_PFN(addr), so what you get here is
>>
>> addr - PHYS_PFN(PHYS_PFN(addr)) ?
>>
>>
>>> +	entry->size		= size;
>>> +	entry->dev_addr		= dma_addr;
>>> +	entry->direction	= direction;
>>> +	entry->map_err_type	= MAP_ERR_NOT_CHECKED;
>>> +
>>> +	add_dma_entry(entry);
>>> +}
>>> +EXPORT_SYMBOL(debug_dma_map_resource);
>>> +
>
diff mbox

Patch

diff --git a/include/linux/dma-debug.h b/include/linux/dma-debug.h
index fe8cb61..c7d844f 100644
--- a/include/linux/dma-debug.h
+++ b/include/linux/dma-debug.h
@@ -56,6 +56,13 @@  extern void debug_dma_alloc_coherent(struct device *dev, size_t size,
 extern void debug_dma_free_coherent(struct device *dev, size_t size,
 				    void *virt, dma_addr_t addr);
 
+extern void debug_dma_map_resource(struct device *dev, phys_addr_t addr,
+				   size_t size, int direction,
+				   dma_addr_t dma_addr);
+
+extern void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
+				     size_t size, int direction);
+
 extern void debug_dma_sync_single_for_cpu(struct device *dev,
 					  dma_addr_t dma_handle, size_t size,
 					  int direction);
@@ -141,6 +148,18 @@  static inline void debug_dma_free_coherent(struct device *dev, size_t size,
 {
 }
 
+static inline void debug_dma_map_resource(struct device *dev, phys_addr_t addr,
+					  size_t size, int direction,
+					  dma_addr_t dma_addr)
+{
+}
+
+static inline void debug_dma_unmap_resource(struct device *dev,
+					    dma_addr_t dma_addr, size_t size,
+					    int direction)
+{
+}
+
 static inline void debug_dma_sync_single_for_cpu(struct device *dev,
 						 dma_addr_t dma_handle,
 						 size_t size, int direction)
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 4a1515f..fb12d5c 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -43,6 +43,7 @@  enum {
 	dma_debug_page,
 	dma_debug_sg,
 	dma_debug_coherent,
+	dma_debug_resource,
 };
 
 enum map_err_types {
@@ -150,8 +151,9 @@  static const char *const maperr2str[] = {
 	[MAP_ERR_CHECKED] = "dma map error checked",
 };
 
-static const char *type2name[4] = { "single", "page",
-				    "scather-gather", "coherent" };
+static const char *type2name[5] = { "single", "page",
+				    "scather-gather", "coherent",
+				    "resource" };
 
 static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
 				   "DMA_FROM_DEVICE", "DMA_NONE" };
@@ -397,6 +399,9 @@  static void hash_bucket_del(struct dma_debug_entry *entry)
 
 static unsigned long long phys_addr(struct dma_debug_entry *entry)
 {
+	if (entry->type == dma_debug_resource)
+		return PHYS_PFN(entry->pfn) + entry->offset;
+
 	return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset;
 }
 
@@ -1493,6 +1498,49 @@  void debug_dma_free_coherent(struct device *dev, size_t size,
 }
 EXPORT_SYMBOL(debug_dma_free_coherent);
 
+void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size,
+			    int direction, dma_addr_t dma_addr)
+{
+	struct dma_debug_entry *entry;
+
+	if (unlikely(dma_debug_disabled()))
+		return;
+
+	entry = dma_entry_alloc();
+	if (!entry)
+		return;
+
+	entry->type		= dma_debug_resource;
+	entry->dev		= dev;
+	entry->pfn		= __phys_to_pfn(addr);
+	entry->offset		= addr - PHYS_PFN(entry->pfn);
+	entry->size		= size;
+	entry->dev_addr		= dma_addr;
+	entry->direction	= direction;
+	entry->map_err_type	= MAP_ERR_NOT_CHECKED;
+
+	add_dma_entry(entry);
+}
+EXPORT_SYMBOL(debug_dma_map_resource);
+
+void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr,
+			      size_t size, int direction)
+{
+	struct dma_debug_entry ref = {
+		.type           = dma_debug_resource,
+		.dev            = dev,
+		.dev_addr       = dma_addr,
+		.size           = size,
+		.direction      = direction,
+	};
+
+	if (unlikely(dma_debug_disabled()))
+		return;
+
+	check_unmap(&ref);
+}
+EXPORT_SYMBOL(debug_dma_unmap_resource);
+
 void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
 				   size_t size, int direction)
 {