4 files changed, 29 insertions, 5 deletions
diff --git a/src/core/file_sys/patch_manager.cpp b/src/core/file_sys/patch_manager.cpp
index 0117cb0bf..1f4928562 100644
--- a/src/core/file_sys/patch_manager.cpp
+++ b/src/core/file_sys/patch_manager.cpp
@@ -168,7 +168,8 @@ bool PatchManager::HasNSOPatch(const std::array<u8, 32>& build_id_) const {
 
 static void ApplyLayeredFS(VirtualFile& romfs, u64 title_id, ContentRecordType type) {
     const auto load_dir = Service::FileSystem::GetModificationLoadRoot(title_id);
-    if (type != ContentRecordType::Program || load_dir == nullptr || load_dir->GetSize() <= 0) {
+    if ((type != ContentRecordType::Program && type != ContentRecordType::Data) ||
+        load_dir == nullptr || load_dir->GetSize() <= 0) {
         return;
     }
 
@@ -218,7 +219,7 @@ VirtualFile PatchManager::PatchRomFS(VirtualFile romfs, u64 ivfc_offset, Content
                                         title_id, static_cast<u8>(type))
                                 .c_str();
 
-    if (type == ContentRecordType::Program)
+    if (type == ContentRecordType::Program || type == ContentRecordType::Data)
         LOG_INFO(Loader, log_string);
     else
         LOG_DEBUG(Loader, log_string);
diff --git a/src/core/file_sys/registered_cache.cpp b/src/core/file_sys/registered_cache.cpp
index 1febb398e..29b100414 100644
--- a/src/core/file_sys/registered_cache.cpp
+++ b/src/core/file_sys/registered_cache.cpp
@@ -2,6 +2,7 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <algorithm>
 #include <regex>
 #include <mbedtls/sha256.h>
 #include "common/assert.h"
@@ -30,6 +31,14 @@ bool operator<(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs)
     return (lhs.title_id < rhs.title_id) || (lhs.title_id == rhs.title_id && lhs.type < rhs.type);
 }
 
+bool operator==(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs) {
+    return std::tie(lhs.title_id, lhs.type) == std::tie(rhs.title_id, rhs.type);
+}
+
+bool operator!=(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs) {
+    return !operator==(lhs, rhs);
+}
+
 static bool FollowsTwoDigitDirFormat(std::string_view name) {
     static const std::regex two_digit_regex("000000[0-9A-F]{2}", std::regex_constants::ECMAScript |
                                                                      std::regex_constants::icase);
@@ -593,6 +602,9 @@ std::vector<RegisteredCacheEntry> RegisteredCacheUnion::ListEntries() const {
             },
             [](const CNMT& c, const ContentRecord& r) { return true; });
     }
+
+    std::sort(out.begin(), out.end());
+    out.erase(std::unique(out.begin(), out.end()), out.end());
     return out;
 }
 
@@ -616,6 +628,9 @@ std::vector<RegisteredCacheEntry> RegisteredCacheUnion::ListEntriesFilter(
                 return true;
             });
     }
+
+    std::sort(out.begin(), out.end());
+    out.erase(std::unique(out.begin(), out.end()), out.end());
     return out;
 }
 } // namespace FileSys
diff --git a/src/core/file_sys/registered_cache.h b/src/core/file_sys/registered_cache.h
index 5ddacba47..5beceffb3 100644
--- a/src/core/file_sys/registered_cache.h
+++ b/src/core/file_sys/registered_cache.h
@@ -50,6 +50,10 @@ constexpr u64 GetUpdateTitleID(u64 base_title_id) {
 // boost flat_map requires operator< for O(log(n)) lookups.
 bool operator<(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs);
 
+// std unique requires operator== to identify duplicates.
+bool operator==(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs);
+bool operator!=(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs);
+
 /*
  * A class that catalogues NCAs in the registered directory structure.
  * Nintendo's registered format follows this structure:
@@ -60,8 +64,8 @@ bool operator<(const RegisteredCacheEntry& lhs, const RegisteredCacheEntry& rhs)
  *         | 00
  *         | 01 <- Actual content split along 4GB boundaries. (optional)
  *
- * (This impl also supports substituting the nca dir for an nca file, as that's more convenient when
- * 4GB splitting can be ignored.)
+ * (This impl also supports substituting the nca dir for an nca file, as that's more convenient
+ * when 4GB splitting can be ignored.)
  */
 class RegisteredCache {
     friend class RegisteredCacheUnion;
diff --git a/src/core/hle/service/filesystem/fsp_srv.cpp b/src/core/hle/service/filesystem/fsp_srv.cpp
index d5dced429..c87721c39 100644
--- a/src/core/hle/service/filesystem/fsp_srv.cpp
+++ b/src/core/hle/service/filesystem/fsp_srv.cpp
@@ -17,6 +17,7 @@
 #include "core/file_sys/errors.h"
 #include "core/file_sys/mode.h"
 #include "core/file_sys/nca_metadata.h"
+#include "core/file_sys/patch_manager.h"
 #include "core/file_sys/savedata_factory.h"
 #include "core/file_sys/vfs.h"
 #include "core/hle/ipc_helpers.h"
@@ -630,6 +631,7 @@ void FSP_SRV::OpenDataStorageByDataId(Kernel::HLERequestContext& ctx) {
               static_cast<u8>(storage_id), unknown, title_id);
 
     auto data = OpenRomFS(title_id, storage_id, FileSys::ContentRecordType::Data);
+
     if (data.Failed()) {
         // TODO(DarkLordZach): Find the right error code to use here
         LOG_ERROR(Service_FS,
@@ -640,7 +642,9 @@ void FSP_SRV::OpenDataStorageByDataId(Kernel::HLERequestContext& ctx) {
         return;
     }
 
-    IStorage storage(std::move(data.Unwrap()));
+    FileSys::PatchManager pm{title_id};
+
+    IStorage storage(pm.PatchRomFS(std::move(data.Unwrap()), 0, FileSys::ContentRecordType::Data));
 
     IPC::ResponseBuilder rb{ctx, 2, 0, 1};
     rb.Push(RESULT_SUCCESS);