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

Increase reference count of source_mount when one of its files is mounted somewhere

See merge request teachos/kernel!42

1 files changed, 11 insertions, 8 deletions

diff --git a/kernel/src/filesystem/mount.tests.cpp b/kernel/src/filesystem/mount.tests.cpp
index 6b66571..c9ff82e 100644
--- a/kernel/src/filesystem/mount.tests.cpp
+++ b/kernel/src/filesystem/mount.tests.cpp
@@ -11,6 +11,8 @@
 
 #include <catch2/catch_test_macros.hpp>
 
+#include <stdexcept>
+
 SCENARIO("Mount construction", "[filesystem][mount]")
 {
   GIVEN("a filesystem and a root dentry")
@@ -21,7 +23,7 @@ SCENARIO("Mount construction", "[filesystem][mount]")
 
     WHEN("constructing a mount with the filesystem and root dentry")
     {
-      auto mount = kernel::filesystem::mount{root_dentry, root_dentry, fs, nullptr};
+      auto mount = kernel::filesystem::mount{root_dentry, root_dentry, fs, nullptr, nullptr};
 
       THEN("the mount has the correct filesystem, root dentry, mount dentry, and mount path")
       {
@@ -32,9 +34,10 @@ SCENARIO("Mount construction", "[filesystem][mount]")
         REQUIRE(mount.is_ready_to_unmount());
       }
 
-      THEN("the mount has no parent mount")
+      THEN("the mount has no parent mount and no source mount")
       {
         REQUIRE(mount.parent_mount() == nullptr);
+        REQUIRE(mount.source_mount() == nullptr);
       }
     }
 
@@ -42,7 +45,7 @@ SCENARIO("Mount construction", "[filesystem][mount]")
     {
       THEN("the constructor panics")
       {
-        REQUIRE_THROWS_AS((kernel::filesystem::mount{root_dentry, root_dentry, nullptr, nullptr}),
+        REQUIRE_THROWS_AS((kernel::filesystem::mount{root_dentry, root_dentry, nullptr, nullptr, nullptr}),
                           kernel::tests::cpu::halt);
       }
     }
@@ -60,7 +63,7 @@ SCENARIO("Mount reference counting", "[filesystem][mount]")
     THEN("reference count can be incremented and decremented, the mount is ready to unmount when the reference "
          "count == 0")
     {
-      auto mount = kernel::filesystem::mount{root_dentry, root_dentry, fs, nullptr};
+      auto mount = kernel::filesystem::mount{root_dentry, root_dentry, fs, nullptr, nullptr};
 
       mount.increment_ref_count();
       REQUIRE(mount.ref_count() == 1);
@@ -70,20 +73,20 @@ SCENARIO("Mount reference counting", "[filesystem][mount]")
       REQUIRE(mount.ref_count() == 2);
       REQUIRE_FALSE(mount.is_ready_to_unmount());
 
-      REQUIRE(mount.decrement_ref_count());
+      mount.decrement_ref_count();
       REQUIRE(mount.ref_count() == 1);
       REQUIRE_FALSE(mount.is_ready_to_unmount());
 
-      REQUIRE(mount.decrement_ref_count());
+      mount.decrement_ref_count();
       REQUIRE(mount.ref_count() == 0);
       REQUIRE(mount.is_ready_to_unmount());
     }
 
     THEN("decrementing reference count when it is already zero does not decrement it below zero")
     {
-      auto mount = kernel::filesystem::mount{root_dentry, root_dentry, fs, nullptr};
+      auto mount = kernel::filesystem::mount{root_dentry, root_dentry, fs, nullptr, nullptr};
 
-      REQUIRE_FALSE(mount.decrement_ref_count());
+      REQUIRE_THROWS_AS(mount.decrement_ref_count(), std::runtime_error);
       REQUIRE(mount.ref_count() == 0);
       REQUIRE(mount.is_ready_to_unmount());
     }