ACPI: property: Add support for parsing buffer property UUID

Add support for newly added buffer property UUID, as defined in the DSD
guide section 3.3 [1]

Link: https://github.com/UEFI/DSD-Guide/blob/main/src/dsd-guide.adoc#buffer-data-extension-uuid
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index b751eb9..7e3d163 100644 (file)
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -55,14 +55,19 @@ static const guid_t ads_guid =
        GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
                  0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
 
+static const guid_t buffer_prop_guid =
+       GUID_INIT(0xedb12dd0, 0x363d, 0x4085,
+                 0xa3, 0xd2, 0x49, 0x52, 0x2c, 0xa1, 0x60, 0xc4);
+
 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
-                                          const union acpi_object *desc,
+                                          union acpi_object *desc,
                                           struct acpi_device_data *data,
                                           struct fwnode_handle *parent);
-static bool acpi_extract_properties(const union acpi_object *desc,
+static bool acpi_extract_properties(acpi_handle handle,
+                                   union acpi_object *desc,
                                    struct acpi_device_data *data);
 
-static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
+static bool acpi_nondev_subnode_extract(union acpi_object *desc,
                                        acpi_handle handle,
                                        const union acpi_object *link,
                                        struct list_head *list,
@@ -81,7 +86,7 @@ static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
        INIT_LIST_HEAD(&dn->data.properties);
        INIT_LIST_HEAD(&dn->data.subnodes);
 
-       result = acpi_extract_properties(desc, &dn->data);
+       result = acpi_extract_properties(handle, desc, &dn->data);
 
        if (handle) {
                acpi_handle scope;
@@ -156,7 +161,7 @@ static bool acpi_nondev_subnode_ok(acpi_handle scope,
 }
 
 static bool acpi_add_nondev_subnodes(acpi_handle scope,
-                                    const union acpi_object *links,
+                                    union acpi_object *links,
                                     struct list_head *list,
                                     struct fwnode_handle *parent)
 {
@@ -164,7 +169,7 @@ static bool acpi_add_nondev_subnodes(acpi_handle scope,
        int i;
 
        for (i = 0; i < links->package.count; i++) {
-               const union acpi_object *link, *desc;
+               union acpi_object *link, *desc;
                acpi_handle handle;
                bool result;
 
@@ -204,7 +209,7 @@ static bool acpi_add_nondev_subnodes(acpi_handle scope,
 }
 
 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
-                                          const union acpi_object *desc,
+                                          union acpi_object *desc,
                                           struct acpi_device_data *data,
                                           struct fwnode_handle *parent)
 {
@@ -212,7 +217,8 @@ static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
 
        /* Look for the ACPI data subnodes GUID. */
        for (i = 0; i < desc->package.count; i += 2) {
-               const union acpi_object *guid, *links;
+               const union acpi_object *guid;
+               union acpi_object *links;
 
                guid = &desc->package.elements[i];
                links = &desc->package.elements[i + 1];
@@ -325,7 +331,7 @@ static bool acpi_is_property_guid(const guid_t *guid)
 
 struct acpi_device_properties *
 acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
-                   const union acpi_object *properties)
+                   union acpi_object *properties)
 {
        struct acpi_device_properties *props;
 
@@ -377,7 +383,104 @@ static bool acpi_tie_nondev_subnodes(struct acpi_device_data *data)
        return true;
 }
 
-static bool acpi_extract_properties(const union acpi_object *desc,
+static void acpi_data_add_buffer_props(acpi_handle handle,
+                                      struct acpi_device_data *data,
+                                      union acpi_object *properties)
+{
+       struct acpi_device_properties *props;
+       union acpi_object *package;
+       size_t alloc_size;
+       unsigned int i;
+       u32 *count;
+
+       if (check_mul_overflow((size_t)properties->package.count,
+                              sizeof(*package) + sizeof(void *),
+                              &alloc_size) ||
+           check_add_overflow(sizeof(*props) + sizeof(*package), alloc_size,
+                              &alloc_size)) {
+               acpi_handle_warn(handle,
+                                "can't allocate memory for %u buffer props",
+                                properties->package.count);
+               return;
+       }
+
+       props = kvzalloc(alloc_size, GFP_KERNEL);
+       if (!props)
+               return;
+
+       props->guid = &buffer_prop_guid;
+       props->bufs = (void *)(props + 1);
+       props->properties = (void *)(props->bufs + properties->package.count);
+
+       /* Outer package */
+       package = props->properties;
+       package->type = ACPI_TYPE_PACKAGE;
+       package->package.elements = package + 1;
+       count = &package->package.count;
+       *count = 0;
+
+       /* Inner packages */
+       package++;
+
+       for (i = 0; i < properties->package.count; i++) {
+               struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+               union acpi_object *property = &properties->package.elements[i];
+               union acpi_object *prop, *obj, *buf_obj;
+               acpi_status status;
+
+               if (property->type != ACPI_TYPE_PACKAGE ||
+                   property->package.count != 2) {
+                       acpi_handle_warn(handle,
+                                        "buffer property %u has %u entries\n",
+                                        i, property->package.count);
+                       continue;
+               }
+
+               prop = &property->package.elements[0];
+               obj = &property->package.elements[1];
+
+               if (prop->type != ACPI_TYPE_STRING ||
+                   obj->type != ACPI_TYPE_STRING) {
+                       acpi_handle_warn(handle,
+                                        "wrong object types %u and %u\n",
+                                        prop->type, obj->type);
+                       continue;
+               }
+
+               status = acpi_evaluate_object_typed(handle, obj->string.pointer,
+                                                   NULL, &buf,
+                                                   ACPI_TYPE_BUFFER);
+               if (ACPI_FAILURE(status)) {
+                       acpi_handle_warn(handle,
+                                        "can't evaluate \"%*pE\" as buffer\n",
+                                        obj->string.length,
+                                        obj->string.pointer);
+                       continue;
+               }
+
+               package->type = ACPI_TYPE_PACKAGE;
+               package->package.elements = prop;
+               package->package.count = 2;
+
+               buf_obj = buf.pointer;
+
+               /* Replace the string object with a buffer object */
+               obj->type = ACPI_TYPE_BUFFER;
+               obj->buffer.length = buf_obj->buffer.length;
+               obj->buffer.pointer = buf_obj->buffer.pointer;
+
+               props->bufs[i] = buf.pointer;
+               package++;
+               (*count)++;
+       }
+
+       if (*count)
+               list_add(&props->list, &data->properties);
+       else
+               kvfree(props);
+}
+
+static bool acpi_extract_properties(acpi_handle scope, union acpi_object *desc,
                                    struct acpi_device_data *data)
 {
        int i;
@@ -387,7 +490,8 @@ static bool acpi_extract_properties(const union acpi_object *desc,
 
        /* Look for the device properties GUID. */
        for (i = 0; i < desc->package.count; i += 2) {
-               const union acpi_object *guid, *properties;
+               const union acpi_object *guid;
+               union acpi_object *properties;
 
                guid = &desc->package.elements[i];
                properties = &desc->package.elements[i + 1];
@@ -401,6 +505,12 @@ static bool acpi_extract_properties(const union acpi_object *desc,
                    properties->type != ACPI_TYPE_PACKAGE)
                        break;
 
+               if (guid_equal((guid_t *)guid->buffer.pointer,
+                              &buffer_prop_guid)) {
+                       acpi_data_add_buffer_props(scope, data, properties);
+                       continue;
+               }
+
                if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
                        continue;
 
@@ -447,7 +557,7 @@ void acpi_init_properties(struct acpi_device *adev)
        if (ACPI_FAILURE(status))
                goto out;
 
-       if (acpi_extract_properties(buf.pointer, &adev->data)) {
+       if (acpi_extract_properties(adev->handle, buf.pointer, &adev->data)) {
                adev->data.pointer = buf.pointer;
                if (acpi_of)
                        acpi_init_of_compatible(adev);
@@ -477,8 +587,14 @@ static void acpi_free_device_properties(struct list_head *list)
        struct acpi_device_properties *props, *tmp;
 
        list_for_each_entry_safe(props, tmp, list, list) {
+               u32 i;
+
                list_del(&props->list);
-               kfree(props);
+               /* Buffer data properties were separately allocated */
+               if (props->bufs)
+                       for (i = 0; i < props->properties->package.count; i++)
+                               ACPI_FREE(props->bufs[i]);
+               kvfree(props);
        }
 }
 

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 0dc1ea0..a169000 100644 (file)
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -344,8 +344,9 @@ struct acpi_device_physical_node {
 
 struct acpi_device_properties {
        const guid_t *guid;
-       const union acpi_object *properties;
+       union acpi_object *properties;
        struct list_head list;
+       void **bufs;
 };
 
 /* ACPI Device Specific Data (_DSD) */

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 44975c1..7c46f15 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1243,7 +1243,7 @@ static inline bool acpi_dev_has_props(const struct acpi_device *adev)
 
 struct acpi_device_properties *
 acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
-                   const union acpi_object *properties);
+                   union acpi_object *properties);
 
 int acpi_node_prop_get(const struct fwnode_handle *fwnode, const char *propname,
                       void **valptr);