Merge branch 'vfs' into 'develop-BA-FS26'

implement basic vfs

See merge request teachos/kernel!16

2 files changed, 80 insertions, 0 deletions

diff --git a/kernel/src/filesystem/devfs/devfs_filesystem.cpp b/kernel/src/filesystem/devfs/devfs_filesystem.cpp
new file mode 100644
index 0000000..c4cd81a
--- /dev/null
+++ b/kernel/src/filesystem/devfs/devfs_filesystem.cpp
@@ -0,0 +1,58 @@
+#include "kernel/filesystem/devfs/devfs_filesystem.hpp"
+
+#include "kernel/devices/device.hpp"
+#include "kernel/devices/storage/storage_management.hpp"
+#include "kernel/filesystem/devfs/devfs_root_inode.hpp"
+#include "kernel/filesystem/device_inode.hpp"
+#include "kernel/filesystem/inode.hpp"
+
+#include <kstd/memory>
+
+#include <algorithm>
+#include <string_view>
+
+namespace filesystem::devfs
+{
+  auto devfs_filesystem::mount(kstd::shared_ptr<devices::device> const &) -> int
+  {
+    m_root_inode = kstd::make_shared<devfs_root_inode>();
+    build_device_inode_table();
+
+    return 0;
+  }
+
+  auto devfs_filesystem::lookup(kstd::shared_ptr<inode> const & parent, std::string_view name)
+      -> kstd::shared_ptr<inode>
+  {
+    if (!parent || !parent->is_directory())
+    {
+      return nullptr;
+    }
+
+    if (parent.get() != m_root_inode.get())
+    {
+      return nullptr;
+    }
+
+    auto it = std::ranges::find_if(m_inodes, [&](auto const & dev_node) {
+      auto device_inode_ptr = static_cast<device_inode *>(dev_node.get());
+      if (!device_inode_ptr)
+      {
+        return false;
+      }
+      return device_inode_ptr->device()->name() == name;
+    });
+    return (it != m_inodes.end()) ? *it : nullptr;
+  }
+
+  auto devfs_filesystem::build_device_inode_table() -> void
+  {
+    m_inodes.clear();
+
+    auto storage_mgmt = devices::storage::storage_management::get();
+    std::ranges::for_each(storage_mgmt.all_controllers(), [&](auto const & controller) {
+      std::ranges::for_each(controller->all_devices(),
+                            [&](auto const & device) { m_inodes.push_back(kstd::make_shared<device_inode>(device)); });
+    });
+  }
+}  // namespace filesystem::devfs
\ No newline at end of file
diff --git a/kernel/src/filesystem/devfs/devfs_root_inode.cpp b/kernel/src/filesystem/devfs/devfs_root_inode.cpp
new file mode 100644
index 0000000..53441b0
--- /dev/null
+++ b/kernel/src/filesystem/devfs/devfs_root_inode.cpp
@@ -0,0 +1,22 @@
+#include "kernel/filesystem/devfs/devfs_root_inode.hpp"
+
+#include "kernel/filesystem/inode.hpp"
+
+#include <cstddef>
+
+namespace filesystem::devfs
+{
+  devfs_root_inode::devfs_root_inode()
+      : inode(inode_kind::directory)
+  {}
+
+  auto devfs_root_inode::read(void * /*buffer*/, size_t /*offset*/, size_t /*size*/) const -> size_t
+  {
+    return 0;
+  }
+
+  auto devfs_root_inode::write(void const * /*buffer*/, size_t /*offset*/, size_t /*size*/) -> size_t
+  {
+    return 0;
+  }
+}  // namespace filesystem::devfs
\ No newline at end of file