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.torok...@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

Reply via email to