[PATCH 1/2] device property: export code duplicating array of property entries

[PATCH 1/2] device property: export code duplicating array of property entries

[Dmitry Torokhov]

When augmenting ACPI-enumerated devices with additional property data based
on DMI info, a module has often several potential property sets, with only
one being active on a given box. In order to save memory it should be
possible to mark everything and __initdata or __initconst, execute DMI
match early, and duplicate relevant properties. Then kernel will discard
the rest of them.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/base/property.c  | 124 +++++++++++++++++++++++++++--------------------
 include/linux/property.h |   3 ++
 2 files changed, 75 insertions(+), 52 deletions(-)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 43a36d68c3fd..ee22ded63e06 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -682,41 +682,8 @@ int fwnode_property_match_string(struct fwnode_handle *fwnode,
 }
 EXPORT_SYMBOL_GPL(fwnode_property_match_string);
 
-/**
- * pset_free_set - releases memory allocated for copied property set
- * @pset: Property set to release
- *
- * Function takes previously copied property set and releases all the
- * memory allocated to it.
- */
-static void pset_free_set(struct property_set *pset)
-{
-	const struct property_entry *prop;
-	size_t i, nval;
-
-	if (!pset)
-		return;
-
-	for (prop = pset->properties; prop->name; prop++) {
-		if (prop->is_array) {
-			if (prop->is_string && prop->pointer.str) {
-				nval = prop->length / sizeof(const char *);
-				for (i = 0; i < nval; i++)
-					kfree(prop->pointer.str[i]);
-			}
-			kfree(prop->pointer.raw_data);
-		} else if (prop->is_string) {
-			kfree(prop->value.str);
-		}
-		kfree(prop->name);
-	}
-
-	kfree(pset->properties);
-	kfree(pset);
-}
-
-static int pset_copy_entry(struct property_entry *dst,
-			   const struct property_entry *src)
+static int property_entry_copy(struct property_entry *dst,
+			       const struct property_entry *src)
 {
 	const char **d, **s;
 	size_t i, nval;
@@ -765,6 +732,71 @@ static int pset_copy_entry(struct property_entry *dst,
 }
 
 /**
+ * property_entries_dup - duplicate array of properties
+ * @properties: array of properties to copy
+ *
+ * This function creates a deep copy of the given NULL-terminated array
+ * of property entries.
+ */
+struct property_entry *property_entries_dup(
+				const struct property_entry *properties)
+{
+	struct property_entry *p;
+	int i, n = 0;
+
+	while (properties[n].name)
+		n++;
+
+	p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
+	if (!p)
+		return ERR_PTR(-ENOMEM);
+
+	for (i = 0; i < n; i++) {
+		int ret = property_entry_copy(&p[i], &properties[i]);
+		if (ret) {
+			kfree(p);
+			return ERR_PTR(ret);
+		}
+	}
+
+	return p;
+}
+EXPORT_SYMBOL_GPL(property_entries_dup);
+
+/**
+ * pset_free_set - releases memory allocated for copied property set
+ * @pset: Property set to release
+ *
+ * Function takes previously copied property set and releases all the
+ * memory allocated to it.
+ */
+static void pset_free_set(struct property_set *pset)
+{
+	const struct property_entry *prop;
+	size_t i, nval;
+
+	if (!pset)
+		return;
+
+	for (prop = pset->properties; prop->name; prop++) {
+		if (prop->is_array) {
+			if (prop->is_string && prop->pointer.str) {
+				nval = prop->length / sizeof(const char *);
+				for (i = 0; i < nval; i++)
+					kfree(prop->pointer.str[i]);
+			}
+			kfree(prop->pointer.raw_data);
+		} else if (prop->is_string) {
+			kfree(prop->value.str);
+		}
+		kfree(prop->name);
+	}
+
+	kfree(pset->properties);
+	kfree(pset);
+}
+
+/**
  * pset_copy_set - copies property set
  * @pset: Property set to copy
  *
@@ -776,32 +808,20 @@ static int pset_copy_entry(struct property_entry *dst,
  */
 static struct property_set *pset_copy_set(const struct property_set *pset)
 {
-	const struct property_entry *entry;
+	struct property_entry *properties;
 	struct property_set *p;
-	size_t i, n = 0;
 
 	p = kzalloc(sizeof(*p), GFP_KERNEL);
 	if (!p)
 		return ERR_PTR(-ENOMEM);
 
-	while (pset->properties[n].name)
-		n++;
-
-	p->properties = kcalloc(n + 1, sizeof(*entry), GFP_KERNEL);
-	if (!p->properties) {
+	properties = property_entries_dup(pset->properties);
+	if (IS_ERR(properties)) {
 		kfree(p);
-		return ERR_PTR(-ENOMEM);
-	}
-
-	for (i = 0; i < n; i++) {
-		int ret = pset_copy_entry(&p->properties[i],
-					  &pset->properties[i]);
-		if (ret) {
-			pset_free_set(p);
-			return ERR_PTR(ret);
-		}
+		return ERR_CAST(properties);
 	}
 
+	p->properties = properties;
 	return p;
 }
 
diff --git a/include/linux/property.h b/include/linux/property.h
index 856e50b2140c..f7fa5891a8c3 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -241,6 +241,9 @@ struct property_entry {
 	.name = _name_,				\
 }
 
+struct property_entry *property_entries_dup(
+				const struct property_entry *properties);
+
 int device_add_properties(struct device *dev,
 			  struct property_entry *properties);
 void device_remove_properties(struct device *dev);
-- 
2.11.0.483.g087da7b7c-goog

[PATCH 2/2] device property: allow constify properties

[Dmitry Torokhov]

There is no reason why statically defined properties should be modifiable,
so let's make device_add_properties() and the rest of pset_*() functions to
take const pointers to properties.

This will allow us to mark properties as const/__initconst at definition
sites.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/base/property.c  | 35 ++++++++++++++++++-----------------
 include/linux/property.h |  2 +-
 2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/drivers/base/property.c b/drivers/base/property.c
index ee22ded63e06..4cbf99cb8ef6 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -21,7 +21,7 @@
 
 struct property_set {
 	struct fwnode_handle fwnode;
-	struct property_entry *properties;
+	const struct property_entry *properties;
 };
 
 static inline bool is_pset_node(struct fwnode_handle *fwnode)
@@ -35,10 +35,10 @@ static inline struct property_set *to_pset_node(struct fwnode_handle *fwnode)
 		container_of(fwnode, struct property_set, fwnode) : NULL;
 }
 
-static struct property_entry *pset_prop_get(struct property_set *pset,
-					    const char *name)
+static const struct property_entry *pset_prop_get(struct property_set *pset,
+						  const char *name)
 {
-	struct property_entry *prop;
+	const struct property_entry *prop;
 
 	if (!pset || !pset->properties)
 		return NULL;
@@ -50,11 +50,11 @@ static struct property_entry *pset_prop_get(struct property_set *pset,
 	return NULL;
 }
 
-static void *pset_prop_find(struct property_set *pset, const char *propname,
-			    size_t length)
+static const void *pset_prop_find(struct property_set *pset,
+				  const char *propname, size_t length)
 {
-	struct property_entry *prop;
-	void *pointer;
+	const struct property_entry *prop;
+	const void *pointer;
 
 	prop = pset_prop_get(pset, propname);
 	if (!prop)
@@ -74,7 +74,7 @@ static int pset_prop_read_u8_array(struct property_set *pset,
 				   const char *propname,
 				   u8 *values, size_t nval)
 {
-	void *pointer;
+	const void *pointer;
 	size_t length = nval * sizeof(*values);
 
 	pointer = pset_prop_find(pset, propname, length);
@@ -89,7 +89,7 @@ static int pset_prop_read_u16_array(struct property_set *pset,
 				    const char *propname,
 				    u16 *values, size_t nval)
 {
-	void *pointer;
+	const void *pointer;
 	size_t length = nval * sizeof(*values);
 
 	pointer = pset_prop_find(pset, propname, length);
@@ -104,7 +104,7 @@ static int pset_prop_read_u32_array(struct property_set *pset,
 				    const char *propname,
 				    u32 *values, size_t nval)
 {
-	void *pointer;
+	const void *pointer;
 	size_t length = nval * sizeof(*values);
 
 	pointer = pset_prop_find(pset, propname, length);
@@ -119,7 +119,7 @@ static int pset_prop_read_u64_array(struct property_set *pset,
 				    const char *propname,
 				    u64 *values, size_t nval)
 {
-	void *pointer;
+	const void *pointer;
 	size_t length = nval * sizeof(*values);
 
 	pointer = pset_prop_find(pset, propname, length);
@@ -133,7 +133,7 @@ static int pset_prop_read_u64_array(struct property_set *pset,
 static int pset_prop_count_elems_of_size(struct property_set *pset,
 					 const char *propname, size_t length)
 {
-	struct property_entry *prop;
+	const struct property_entry *prop;
 
 	prop = pset_prop_get(pset, propname);
 	if (!prop)
@@ -146,7 +146,7 @@ static int pset_prop_read_string_array(struct property_set *pset,
 				       const char *propname,
 				       const char **strings, size_t nval)
 {
-	void *pointer;
+	const void *pointer;
 	size_t length = nval * sizeof(*strings);
 
 	pointer = pset_prop_find(pset, propname, length);
@@ -160,8 +160,8 @@ static int pset_prop_read_string_array(struct property_set *pset,
 static int pset_prop_read_string(struct property_set *pset,
 				 const char *propname, const char **strings)
 {
-	struct property_entry *prop;
-	const char **pointer;
+	const struct property_entry *prop;
+	const char * const *pointer;
 
 	prop = pset_prop_get(pset, propname);
 	if (!prop)
@@ -867,7 +867,8 @@ EXPORT_SYMBOL_GPL(device_remove_properties);
  * @dev as its secondary firmware node. The function takes a copy of
  * @properties.
  */
-int device_add_properties(struct device *dev, struct property_entry *properties)
+int device_add_properties(struct device *dev,
+			  const struct property_entry *properties)
 {
 	struct property_set *p, pset;
 
diff --git a/include/linux/property.h b/include/linux/property.h
index f7fa5891a8c3..3aeb4d7acd68 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -245,7 +245,7 @@ struct property_entry *property_entries_dup(
 				const struct property_entry *properties);
 
 int device_add_properties(struct device *dev,
-			  struct property_entry *properties);
+			  const struct property_entry *properties);
 void device_remove_properties(struct device *dev);
 
 bool device_dma_supported(struct device *dev);
-- 
2.11.0.483.g087da7b7c-goog

Re: [PATCH 2/2] device property: allow constify properties

[Mika Westerberg]

On Sun, Jan 22, 2017 at 11:38:49PM -0800, Dmitry Torokhov wrote:
> There is no reason why statically defined properties should be modifiable,
> so let's make device_add_properties() and the rest of pset_*() functions to
> take const pointers to properties.
> 
> This will allow us to mark properties as const/__initconst at definition
> sites.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Re: [PATCH 2/2] device property: allow constify properties

[Andy Shevchenko]

On Sun, 2017-01-22 at 23:38 -0800, Dmitry Torokhov wrote:
> There is no reason why statically defined properties should be
> modifiable,
> so let's make device_add_properties() and the rest of pset_*()
> functions to
> take const pointers to properties.
> 
> This will allow us to mark properties as const/__initconst at
> definition
> sites.
> 

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>  drivers/base/property.c  | 35 ++++++++++++++++++-----------------
>  include/linux/property.h |  2 +-
>  2 files changed, 19 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index ee22ded63e06..4cbf99cb8ef6 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c
> @@ -21,7 +21,7 @@
>  
>  struct property_set {
>  	struct fwnode_handle fwnode;
> -	struct property_entry *properties;
> +	const struct property_entry *properties;
>  };
>  
>  static inline bool is_pset_node(struct fwnode_handle *fwnode)
> @@ -35,10 +35,10 @@ static inline struct property_set
> *to_pset_node(struct fwnode_handle *fwnode)
>  		container_of(fwnode, struct property_set, fwnode) :
> NULL;
>  }
>  
> -static struct property_entry *pset_prop_get(struct property_set
> *pset,
> -					    const char *name)
> +static const struct property_entry *pset_prop_get(struct property_set
> *pset,
> +						  const char *name)
>  {
> -	struct property_entry *prop;
> +	const struct property_entry *prop;
>  
>  	if (!pset || !pset->properties)
>  		return NULL;
> @@ -50,11 +50,11 @@ static struct property_entry *pset_prop_get(struct
> property_set *pset,
>  	return NULL;
>  }
>  
> -static void *pset_prop_find(struct property_set *pset, const char
> *propname,
> -			    size_t length)
> +static const void *pset_prop_find(struct property_set *pset,
> +				  const char *propname, size_t
> length)
>  {
> -	struct property_entry *prop;
> -	void *pointer;
> +	const struct property_entry *prop;
> +	const void *pointer;
>  
>  	prop = pset_prop_get(pset, propname);
>  	if (!prop)
> @@ -74,7 +74,7 @@ static int pset_prop_read_u8_array(struct
> property_set *pset,
>  				   const char *propname,
>  				   u8 *values, size_t nval)
>  {
> -	void *pointer;
> +	const void *pointer;
>  	size_t length = nval * sizeof(*values);
>  
>  	pointer = pset_prop_find(pset, propname, length);
> @@ -89,7 +89,7 @@ static int pset_prop_read_u16_array(struct
> property_set *pset,
>  				    const char *propname,
>  				    u16 *values, size_t nval)
>  {
> -	void *pointer;
> +	const void *pointer;
>  	size_t length = nval * sizeof(*values);
>  
>  	pointer = pset_prop_find(pset, propname, length);
> @@ -104,7 +104,7 @@ static int pset_prop_read_u32_array(struct
> property_set *pset,
>  				    const char *propname,
>  				    u32 *values, size_t nval)
>  {
> -	void *pointer;
> +	const void *pointer;
>  	size_t length = nval * sizeof(*values);
>  
>  	pointer = pset_prop_find(pset, propname, length);
> @@ -119,7 +119,7 @@ static int pset_prop_read_u64_array(struct
> property_set *pset,
>  				    const char *propname,
>  				    u64 *values, size_t nval)
>  {
> -	void *pointer;
> +	const void *pointer;
>  	size_t length = nval * sizeof(*values);
>  
>  	pointer = pset_prop_find(pset, propname, length);
> @@ -133,7 +133,7 @@ static int pset_prop_read_u64_array(struct
> property_set *pset,
>  static int pset_prop_count_elems_of_size(struct property_set *pset,
>  					 const char *propname, size_t
> length)
>  {
> -	struct property_entry *prop;
> +	const struct property_entry *prop;
>  
>  	prop = pset_prop_get(pset, propname);
>  	if (!prop)
> @@ -146,7 +146,7 @@ static int pset_prop_read_string_array(struct
> property_set *pset,
>  				       const char *propname,
>  				       const char **strings, size_t
> nval)
>  {
> -	void *pointer;
> +	const void *pointer;
>  	size_t length = nval * sizeof(*strings);
>  
>  	pointer = pset_prop_find(pset, propname, length);
> @@ -160,8 +160,8 @@ static int pset_prop_read_string_array(struct
> property_set *pset,
>  static int pset_prop_read_string(struct property_set *pset,
>  				 const char *propname, const char
> **strings)
>  {
> -	struct property_entry *prop;
> -	const char **pointer;
> +	const struct property_entry *prop;
> +	const char * const *pointer;
>  
>  	prop = pset_prop_get(pset, propname);
>  	if (!prop)
> @@ -867,7 +867,8 @@ EXPORT_SYMBOL_GPL(device_remove_properties);
>   * @dev as its secondary firmware node. The function takes a copy of
>   * @properties.
>   */
> -int device_add_properties(struct device *dev, struct property_entry
> *properties)
> +int device_add_properties(struct device *dev,
> +			  const struct property_entry *properties)
>  {
>  	struct property_set *p, pset;
>  
> diff --git a/include/linux/property.h b/include/linux/property.h
> index f7fa5891a8c3..3aeb4d7acd68 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h
> @@ -245,7 +245,7 @@ struct property_entry *property_entries_dup(
>  				const struct property_entry
> *properties);
>  
>  int device_add_properties(struct device *dev,
> -			  struct property_entry *properties);
> +			  const struct property_entry *properties);
>  void device_remove_properties(struct device *dev);
>  
>  bool device_dma_supported(struct device *dev);

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

Re: [PATCH 1/2] device property: export code duplicating array of property entries

[Mika Westerberg]

On Sun, Jan 22, 2017 at 11:38:48PM -0800, Dmitry Torokhov wrote:
> When augmenting ACPI-enumerated devices with additional property data based
> on DMI info, a module has often several potential property sets, with only
> one being active on a given box. In order to save memory it should be
> possible to mark everything and __initdata or __initconst, execute DMI
> match early, and duplicate relevant properties. Then kernel will discard
> the rest of them.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

I think this is good idea, so please feel free to add my,

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Re: [PATCH 1/2] device property: export code duplicating array of property entries

[Andy Shevchenko]

On Sun, 2017-01-22 at 23:38 -0800, Dmitry Torokhov wrote:
> When augmenting ACPI-enumerated devices with additional property data
> based
> on DMI info, a module has often several potential property sets, with
> only
> one being active on a given box. In order to save memory it should be
> possible to mark everything and __initdata or __initconst, execute DMI
> match early, and duplicate relevant properties. Then kernel will
> discard
> the rest of them.
> 

Looks good to me.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Couple of style nitpicks.

> 
> +struct property_entry *property_entries_dup(
> +				const struct property_entry
> *properties)

Can we use

struct propert_entry *
property_entries_dup(...)

?


> +struct property_entry *property_entries_dup(
> +				const struct property_entry
> *properties);
> 

Ditto.

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy

Re: [PATCH 1/2] device property: export code duplicating array of property entries

[Dmitry Torokhov]

On Mon, Jan 23, 2017 at 05:00:38PM +0200, Andy Shevchenko wrote:
> On Sun, 2017-01-22 at 23:38 -0800, Dmitry Torokhov wrote:
> > When augmenting ACPI-enumerated devices with additional property data
> > based
> > on DMI info, a module has often several potential property sets, with
> > only
> > one being active on a given box. In order to save memory it should be
> > possible to mark everything and __initdata or __initconst, execute DMI
> > match early, and duplicate relevant properties. Then kernel will
> > discard
> > the rest of them.
> > 
> 
> Looks good to me.
> 
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
> Couple of style nitpicks.
> 
> > 
> > +struct property_entry *property_entries_dup(
> > +				const struct property_entry
> > *properties)
> 
> Can we use
> 
> struct propert_entry *
> property_entries_dup(...)
> 
> ?

Sure, will adjust. I also realized we'll need property_entries_free()
for proper cleanups. I'll repost the series.

> 
> 
> > +struct property_entry *property_entries_dup(
> > +				const struct property_entry
> > *properties);
> > 
> 
> Ditto.
> 
> -- 
> Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Intel Finland Oy

-- 
Dmitry

Re: [PATCH 1/2] device property: export code duplicating array of property entries

[Rafael J. Wysocki]

On 1/23/2017 11:46 PM, Dmitry Torokhov wrote:
> On Mon, Jan 23, 2017 at 05:00:38PM +0200, Andy Shevchenko wrote:
>> On Sun, 2017-01-22 at 23:38 -0800, Dmitry Torokhov wrote:
>>> When augmenting ACPI-enumerated devices with additional property data
>>> based
>>> on DMI info, a module has often several potential property sets, with
>>> only
>>> one being active on a given box. In order to save memory it should be
>>> possible to mark everything and __initdata or __initconst, execute DMI
>>> match early, and duplicate relevant properties. Then kernel will
>>> discard
>>> the rest of them.
>>>
>> Looks good to me.
>>
>> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>>
>> Couple of style nitpicks.
>>
>>> +struct property_entry *property_entries_dup(
>>> +				const struct property_entry
>>> *properties)
>> Can we use
>>
>> struct propert_entry *
>> property_entries_dup(...)
>>
>> ?
> Sure, will adjust. I also realized we'll need property_entries_free()
> for proper cleanups. I'll repost the series.

Can you please CC it to linux-acpi while at that?  It will help to 
handle it.

Thanks,
Rafael