Merge branch 'mount-reference-count' into 'develop-BA-FS26'

Mount reference count

See merge request teachos/kernel!37

2 files changed, 32 insertions, 2 deletions

diff --git a/kernel/kapi/filesystem.cpp b/kernel/kapi/filesystem.cpp
index 4c68f28..53a71be 100644
--- a/kernel/kapi/filesystem.cpp
+++ b/kernel/kapi/filesystem.cpp
@@ -35,7 +35,7 @@ namespace kapi::filesystem
   {
     if (auto dentry = kernel::filesystem::vfs::get().open(path))
     {
-      auto open_file_descriptor = kstd::make_shared<kernel::filesystem::open_file_descriptor>(dentry->get_inode());
+      auto open_file_descriptor = kstd::make_shared<kernel::filesystem::open_file_descriptor>(dentry);
       return kernel::filesystem::open_file_table::get().add_file(open_file_descriptor);
     }
 
@@ -44,7 +44,15 @@ namespace kapi::filesystem
 
   auto close(int file_descriptor) -> int
   {
-    return kernel::filesystem::open_file_table::get().remove_file(file_descriptor);
+    if (auto open_file_descriptor = kernel::filesystem::open_file_table::get().get_file(file_descriptor))
+    {
+      if (kernel::filesystem::vfs::get().close(open_file_descriptor->get_dentry()->get_absolute_path().view()) ==
+          kernel::filesystem::vfs::operation_result::success)
+      {
+        return kernel::filesystem::open_file_table::get().remove_file(file_descriptor);
+      }
+    }
+    return -1;
   }
 
   auto read(int file_descriptor, void * buffer, size_t size) -> ssize_t
diff --git a/kernel/kapi/filesystem.tests.cpp b/kernel/kapi/filesystem.tests.cpp
index 1d1f8ee..d241afa 100644
--- a/kernel/kapi/filesystem.tests.cpp
+++ b/kernel/kapi/filesystem.tests.cpp
@@ -103,6 +103,19 @@ SCENARIO_METHOD(kernel::tests::filesystem::storage_boot_module_vfs_fixture, "Kap
       REQUIRE(kapi::filesystem::umount("/information") == 0);
     }
 
+    THEN("a filesystem cannot be unmounted if files are still open and can be unmounted after files are closed")
+    {
+      REQUIRE(kapi::filesystem::mount("/dev/ram16", "/information") == 0);
+
+      auto fd = kapi::filesystem::open("/information/monkey_house/monkey_1.txt");
+      REQUIRE(fd >= 0);
+
+      REQUIRE(kapi::filesystem::umount("/information") < 0);
+
+      REQUIRE(kapi::filesystem::close(fd) == 0);
+      REQUIRE(kapi::filesystem::umount("/information") == 0);
+    }
+
     THEN("device can be opened as file and read from")
     {
       auto fd = kapi::filesystem::open("/dev/ram0");
@@ -158,6 +171,15 @@ SCENARIO_METHOD(kernel::tests::filesystem::storage_boot_module_vfs_fixture, "Kap
       REQUIRE(kapi::filesystem::close(999) < 0);
     }
 
+    THEN("same file cannot be closed twice")
+    {
+      auto fd = kapi::filesystem::open("/information/info_1.txt");
+      REQUIRE(fd >= 0);
+
+      REQUIRE(kapi::filesystem::close(fd) == 0);
+      REQUIRE(kapi::filesystem::close(fd) < 0);
+    }
+
     THEN("not opened files cannot be read from")
     {
       std::vector<std::byte> buffer(10);