Add a setting to disable creating a backing memory region for SVD regions

This is apart of https://github.com/Vector35/binaryninja-api/issues/6678

2 files changed, 38 insertions, 16 deletions

diff --git a/plugins/svd/src/mapper.rs b/plugins/svd/src/mapper.rs
index c0ca5e99..0a476481 100644
--- a/plugins/svd/src/mapper.rs
+++ b/plugins/svd/src/mapper.rs
@@ -163,24 +163,29 @@ impl DeviceMapper {
         let memory_info =
             self.peripheral_block_memory_info(peripheral, address_block, block_name.clone());
 
-        // Add the block segment, section and backing memory.
-        let data_memory = DataBuffer::new(&vec![0; address_block.size as usize]).unwrap();
-        let added_memory = view.memory_map().add_data_memory_region(
-            &block_name,
-            block_addr,
-            &data_memory,
-            Some(memory_info.segment_flags),
-        );
-        view.add_segment(memory_info.segment);
-        view.add_section(memory_info.section);
-
-        if !added_memory {
-            log::error!(
-                "Failed to add memory for peripheral block! {} @ 0x{:x}",
-                block_name,
-                block_addr
+        // Add the block segment, section and backing memory (optional).
+        if self.settings.add_backing_regions {
+            // Because adding a memory region will add a possibly large memory buffer in the BNDB, this
+            // is optional. if a user disables this, they cannot write to the segment until they add a backing memory region.
+            let data_memory = DataBuffer::new(&vec![0; address_block.size as usize]).unwrap();
+            let added_memory = view.memory_map().add_data_memory_region(
+                &block_name,
+                block_addr,
+                &data_memory,
+                Some(memory_info.segment_flags),
             );
+            
+            if !added_memory {
+                log::error!(
+                    "Failed to add memory for peripheral block! {} @ 0x{:x}",
+                    block_name,
+                    block_addr
+                );
+            }
         }
+        
+        view.add_segment(memory_info.segment);
+        view.add_section(memory_info.section);
 
         // Handle usage specific stuff like adding registers.
         match address_block.usage {
diff --git a/plugins/svd/src/settings.rs b/plugins/svd/src/settings.rs
index ca6df47f..9b4a9e07 100644
--- a/plugins/svd/src/settings.rs
+++ b/plugins/svd/src/settings.rs
@@ -5,12 +5,15 @@ use std::path::PathBuf;
 
 #[derive(Debug, Clone)]
 pub struct LoadSettings {
+    pub add_backing_regions: bool,
     pub add_bitfields: bool,
     pub add_comments: bool,
     pub auto_load_file: Option<PathBuf>,
 }
 
 impl LoadSettings {
+    pub const ADD_BACKING_REGIONS_DEFAULT: bool = true;
+    pub const ADD_BACKING_REGIONS_SETTING: &'static str = "analysis.svd.addBackingRegions";
     pub const ADD_BITFIELDS_DEFAULT: bool = true;
     pub const ADD_BITFIELDS_SETTING: &'static str = "analysis.svd.addBitfields";
     pub const ADD_COMMENTS_DEFAULT: bool = true;
@@ -21,6 +24,15 @@ impl LoadSettings {
     pub fn register() {
         let bn_settings = Settings::new();
 
+        let add_backing_region_props = json!({
+            "title" : "Add Backing Regions",
+            "type" : "boolean",
+            "default" : Self::ADD_BACKING_REGIONS_DEFAULT,
+            "description" : "Whether to add backing regions. Backing regions allow you to write to the underlying memory of a view, but will take up space in the BNDB.",
+        });
+        bn_settings
+            .register_setting_json(Self::ADD_BACKING_REGIONS_SETTING, add_backing_region_props.to_string());
+        
         let add_bitfields_props = json!({
             "title" : "Add Bitfields",
             "type" : "boolean",
@@ -53,6 +65,10 @@ impl LoadSettings {
         let mut load_settings = LoadSettings::default();
         let settings = Settings::new();
         let mut query_opts = QueryOptions::new_with_view(view);
+        if settings.contains(Self::ADD_BACKING_REGIONS_SETTING) {
+            load_settings.add_backing_regions =
+                settings.get_bool_with_opts(Self::ADD_BACKING_REGIONS_SETTING, &mut query_opts);
+        }
         if settings.contains(Self::ADD_BITFIELDS_SETTING) {
             load_settings.add_bitfields =
                 settings.get_bool_with_opts(Self::ADD_BITFIELDS_SETTING, &mut query_opts);
@@ -76,6 +92,7 @@ impl LoadSettings {
 impl Default for LoadSettings {
     fn default() -> Self {
         Self {
+            add_backing_regions: Self::ADD_BACKING_REGIONS_DEFAULT,
             add_bitfields: Self::ADD_BITFIELDS_DEFAULT,
             add_comments: Self::ADD_COMMENTS_DEFAULT,
             auto_load_file: None,