Re: [PATCH v5 06/14] software node: get rid of property_set_pointer()

2019-10-15 Thread Dmitry Torokhov
On Tue, Oct 15, 2019 at 03:09:49PM +0300, Andy Shevchenko wrote:
> On Fri, Oct 11, 2019 at 04:07:13PM -0700, Dmitry Torokhov wrote:
> > Instead of explicitly setting values of integer types when copying
> > property entries lets just copy entire value union when processing
> > non-array values.
> > 
> > For value arrays we no longer use union of pointers, but rather a single
> > void pointer, which allows us to remove property_set_pointer().
> > 
> > In property_get_pointer() we do not need to handle each data type
> > separately, we can simply return either the pointer or pointer to values
> > union.
> > 
> > We are not losing anything from removing typed pointer union because the
> > upper layers do their accesses through void pointers anyway, and we
> > trust the "type" of the property when interpret the data. We rely on
> > users of property entries on using PROPERTY_ENTRY_XXX() macros to
> > properly initialize entries instead of poking in the instances directly.
> 
> I'm not sure about this change since the struct definition is still available
> to use. If we would change it to be opaque pointer, it will be possible to get
> rid of the type differentiation in cleaner way.

We expose type and other fields that should not be manipulated directly,
for the benefit of being able to use static initializers. Having value
structure allows for not too ugly non-array initializers.

Thanks.

-- 
Dmitry


Re: [PATCH v5 06/14] software node: get rid of property_set_pointer()

2019-10-15 Thread Andy Shevchenko
On Fri, Oct 11, 2019 at 04:07:13PM -0700, Dmitry Torokhov wrote:
> Instead of explicitly setting values of integer types when copying
> property entries lets just copy entire value union when processing
> non-array values.
> 
> For value arrays we no longer use union of pointers, but rather a single
> void pointer, which allows us to remove property_set_pointer().
> 
> In property_get_pointer() we do not need to handle each data type
> separately, we can simply return either the pointer or pointer to values
> union.
> 
> We are not losing anything from removing typed pointer union because the
> upper layers do their accesses through void pointers anyway, and we
> trust the "type" of the property when interpret the data. We rely on
> users of property entries on using PROPERTY_ENTRY_XXX() macros to
> properly initialize entries instead of poking in the instances directly.

I'm not sure about this change since the struct definition is still available
to use. If we would change it to be opaque pointer, it will be possible to get
rid of the type differentiation in cleaner way.

Anyway, perhaps somebody else can look at this.

-- 
With Best Regards,
Andy Shevchenko




[PATCH v5 06/14] software node: get rid of property_set_pointer()

2019-10-11 Thread Dmitry Torokhov
Instead of explicitly setting values of integer types when copying
property entries lets just copy entire value union when processing
non-array values.

For value arrays we no longer use union of pointers, but rather a single
void pointer, which allows us to remove property_set_pointer().

In property_get_pointer() we do not need to handle each data type
separately, we can simply return either the pointer or pointer to values
union.

We are not losing anything from removing typed pointer union because the
upper layers do their accesses through void pointers anyway, and we
trust the "type" of the property when interpret the data. We rely on
users of property entries on using PROPERTY_ENTRY_XXX() macros to
properly initialize entries instead of poking in the instances directly.

Signed-off-by: Dmitry Torokhov 
---
 drivers/base/swnode.c| 90 +---
 include/linux/property.h | 12 ++
 2 files changed, 22 insertions(+), 80 deletions(-)

diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index 2f2248c9003c..26e56dd66436 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -103,71 +103,15 @@ property_entry_get(const struct property_entry *prop, 
const char *name)
return NULL;
 }
 
-static void
-property_set_pointer(struct property_entry *prop, const void *pointer)
-{
-   switch (prop->type) {
-   case DEV_PROP_U8:
-   if (prop->is_array)
-   prop->pointer.u8_data = pointer;
-   else
-   prop->value.u8_data = *((u8 *)pointer);
-   break;
-   case DEV_PROP_U16:
-   if (prop->is_array)
-   prop->pointer.u16_data = pointer;
-   else
-   prop->value.u16_data = *((u16 *)pointer);
-   break;
-   case DEV_PROP_U32:
-   if (prop->is_array)
-   prop->pointer.u32_data = pointer;
-   else
-   prop->value.u32_data = *((u32 *)pointer);
-   break;
-   case DEV_PROP_U64:
-   if (prop->is_array)
-   prop->pointer.u64_data = pointer;
-   else
-   prop->value.u64_data = *((u64 *)pointer);
-   break;
-   case DEV_PROP_STRING:
-   if (prop->is_array)
-   prop->pointer.str = pointer;
-   else
-   prop->value.str = pointer;
-   break;
-   default:
-   break;
-   }
-}
-
 static const void *property_get_pointer(const struct property_entry *prop)
 {
-   switch (prop->type) {
-   case DEV_PROP_U8:
-   if (prop->is_array)
-   return prop->pointer.u8_data;
-   return >value.u8_data;
-   case DEV_PROP_U16:
-   if (prop->is_array)
-   return prop->pointer.u16_data;
-   return >value.u16_data;
-   case DEV_PROP_U32:
-   if (prop->is_array)
-   return prop->pointer.u32_data;
-   return >value.u32_data;
-   case DEV_PROP_U64:
-   if (prop->is_array)
-   return prop->pointer.u64_data;
-   return >value.u64_data;
-   case DEV_PROP_STRING:
-   if (prop->is_array)
-   return prop->pointer.str;
-   return >value.str;
-   default:
+   if (!prop->length)
return NULL;
-   }
+
+   if (prop->is_array)
+   return prop->pointer;
+
+   return >value;
 }
 
 static const void *property_entry_find(const struct property_entry *props,
@@ -322,13 +266,15 @@ static int property_entry_read_string_array(const struct 
property_entry *props,
 static void property_entry_free_data(const struct property_entry *p)
 {
const void *pointer = property_get_pointer(p);
+   const char * const *src_str;
size_t i, nval;
 
if (p->is_array) {
-   if (p->type == DEV_PROP_STRING && p->pointer.str) {
+   if (p->type == DEV_PROP_STRING && p->pointer) {
+   src_str = p->pointer;
nval = p->length / sizeof(const char *);
for (i = 0; i < nval; i++)
-   kfree(p->pointer.str[i]);
+   kfree(src_str[i]);
}
kfree(pointer);
} else if (p->type == DEV_PROP_STRING) {
@@ -341,6 +287,7 @@ static const char * const *
 property_copy_string_array(const struct property_entry *src)
 {
const char **d;
+   const char * const *src_str = src->pointer;
size_t nval = src->length / sizeof(*d);
int i;
 
@@ -349,8 +296,8 @@ property_copy_string_array(const struct property_entry *src)
return NULL;
 
for (i = 0; i < nval; i++) {
-   d[i] = kstrdup(src->pointer.str[i],