From 8be15b96e4113903c3501a6dee3fa6108665ff29 Mon Sep 17 00:00:00 2001
From: Lucjan Bryndza <lucjan.bryndza@mudita.com>
Date: Wed, 2 Dec 2020 09:47:17 +0100
Subject: [PATCH] [EGD-4498] Virtual Filesystem Core Framework (#1074)

* [EGD-4498] Registering and unregistering VFS

* [EGD-4498] Mount structures added

* [EGD-4498] Mount filesystem completed

* [EGD-4498] Mount / unmount / and find mount impl

* [EGD-4498] Per thread directory TLS

* [EGD-4489] Absolute paths implementation

* [EGD-4498] Git ignore vim

* [EGD-4498] VFS core functions without cwd

* [EGD-4498] Other syscalls

* [EGD-4498] Code review fixes

* [EGD-4498] Code review #2

Signed-off-by: Lucjan Bryndza <lucjan.bryndza@mudita.com>

* [EGD-4498] Code review small fixes vol #3

Signed-off-by: Lucjan Bryndza <lucjan.bryndza@mudita.com>
---
 .gitignore                                    |   6 +
 module-utils/split_sv.hpp                     |  33 +++
 module-vfs/CMakeLists.txt                     |   4 +
 .../linux/purefs/src/fs/thread_local_cwd.cpp  |  27 +++
 .../rt1051/purefs/src/fs/thread_local_cwd.cpp |  57 +++++
 .../internal/purefs/fs/directory_handle.hpp   |   6 +-
 .../internal/purefs/fs/file_handle.hpp        |   8 +-
 .../purefs/{utils => fs}/handle_mapper.hpp    |   4 +-
 .../internal/purefs/fs/mount_point.hpp        |  34 ++-
 .../internal/purefs/fs/thread_local_cwd.hpp   |  12 +
 .../include/user/purefs/fs/filesystem.hpp     | 126 ++++++++++-
 .../user/purefs/fs/filesystem_operation.hpp   |  69 ------
 .../user/purefs/fs/filesystem_operations.hpp  |  84 +++++++
 module-vfs/src/purefs/fs/filesystem.cpp       | 214 ++++++++++++++++++
 module-vfs/src/purefs/fs/filesystem_cwd.cpp   |  32 +++
 .../src/purefs/fs/filesystem_operations.cpp   | 104 +++++++++
 .../src/purefs/fs/filesystem_syscalls.cpp     | 139 ++++++++++++
 module-vfs/targets/Target_Linux.cmake         |   1 +
 module-vfs/targets/Target_RT1051.cmake        |   7 +-
 19 files changed, 873 insertions(+), 94 deletions(-)
 create mode 100644 module-utils/split_sv.hpp
 create mode 100644 module-vfs/board/linux/purefs/src/fs/thread_local_cwd.cpp
 create mode 100644 module-vfs/board/rt1051/purefs/src/fs/thread_local_cwd.cpp
 rename module-vfs/include/internal/purefs/{utils => fs}/handle_mapper.hpp (93%)
 create mode 100644 module-vfs/include/internal/purefs/fs/thread_local_cwd.hpp
 delete mode 100644 module-vfs/include/user/purefs/fs/filesystem_operation.hpp
 create mode 100644 module-vfs/include/user/purefs/fs/filesystem_operations.hpp
 create mode 100644 module-vfs/src/purefs/fs/filesystem.cpp
 create mode 100644 module-vfs/src/purefs/fs/filesystem_cwd.cpp
 create mode 100644 module-vfs/src/purefs/fs/filesystem_operations.cpp
 create mode 100644 module-vfs/src/purefs/fs/filesystem_syscalls.cpp

diff --git a/.gitignore b/.gitignore
index 1a81adf58c303ccf657f1751559b12f435489fb4..65b0fde019928cde083e1e4345835d76ec6b45f0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -43,3 +43,9 @@ docker/Dockerfile
 docker/assets/actions*
 docker/assets/cmake*
 docker/assets/gcc-arm*
+
+# vim temporary files
+*.swp
+*.swo
+tags
+.ycm_extra_conf.py
diff --git a/module-utils/split_sv.hpp b/module-utils/split_sv.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..3fb672eaae72236e45b9562a88900ba6a7283835
--- /dev/null
+++ b/module-utils/split_sv.hpp
@@ -0,0 +1,33 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+
+#pragma once
+#include <list>
+#include <string>
+#include <type_traits>
+
+namespace utils
+{
+    template <template <class, class> class Container, class T, class Allocator = std::allocator<T>>
+    auto split(T strv, T delims = " ")
+    {
+        static_assert(std::is_same<T, std::string>::value || std::is_same<T, std::string_view>::value,
+                      "std::string or std::string_view expected");
+        Container<T, Allocator> output;
+        size_t first = 0;
+
+        while (first < strv.size()) {
+            const auto second = strv.find_first_of(delims, first);
+
+            if (first != second)
+                output.emplace_back(strv.substr(first, second - first));
+
+            if (second == std::string_view::npos)
+                break;
+
+            first = second + 1;
+        }
+
+        return output;
+    }
+} // namespace utils
diff --git a/module-vfs/CMakeLists.txt b/module-vfs/CMakeLists.txt
index 77d9de54a23b2e7dd712f2d1de8c7f220532dbaf..c0576ecab979831699a4d1cbdba43a17b8ae6710 100644
--- a/module-vfs/CMakeLists.txt
+++ b/module-vfs/CMakeLists.txt
@@ -49,6 +49,10 @@ set(SOURCES ""
         src/purefs/blkdev/disk.cpp
         src/purefs/blkdev/partition_parser.cpp
         src/purefs/blkdev/disk_handle.cpp
+        src/purefs/fs/filesystem.cpp
+        src/purefs/fs/filesystem_operations.cpp
+        src/purefs/fs/filesystem_syscalls.cpp
+        src/purefs/fs/filesystem_cwd.cpp
         src/deprecated/vfs-utils.cpp
         src/deprecated/vfs.cpp
         src/deprecated/vfsNotifier.cpp
diff --git a/module-vfs/board/linux/purefs/src/fs/thread_local_cwd.cpp b/module-vfs/board/linux/purefs/src/fs/thread_local_cwd.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..77750d2cb8d6e5052d060e9e4ed9393df73864f8
--- /dev/null
+++ b/module-vfs/board/linux/purefs/src/fs/thread_local_cwd.cpp
@@ -0,0 +1,27 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+
+#include <string>
+#include <purefs/fs/thread_local_cwd.hpp>
+
+namespace purefs::fs::internal
+{
+
+    namespace
+    {
+        thread_local std::string cwd_per_thread{"/"};
+    }
+    auto get_thread_local_cwd_path() noexcept -> std::string_view
+    {
+        return cwd_per_thread;
+    }
+    auto set_thread_cwd_path(std::string_view path) noexcept -> int
+    {
+        cwd_per_thread = path;
+        return 0;
+    }
+    auto cleanup_thread_local_cwd_mem() -> void
+    {
+        cwd_per_thread.erase();
+    }
+} // namespace purefs::fs::internal
diff --git a/module-vfs/board/rt1051/purefs/src/fs/thread_local_cwd.cpp b/module-vfs/board/rt1051/purefs/src/fs/thread_local_cwd.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..48eb12ccc2d67335497274836146c90a521182a4
--- /dev/null
+++ b/module-vfs/board/rt1051/purefs/src/fs/thread_local_cwd.cpp
@@ -0,0 +1,57 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+#include <thread.hpp>
+#include <limits.h>
+#include <cstring>
+#include <purefs/fs/thread_local_cwd.hpp>
+
+#if configNUM_THREAD_LOCAL_STORAGE_POINTERS < 4
+#error Not enough TLS pointers
+#endif
+
+namespace purefs::fs::internal
+{
+    namespace
+    {
+        constexpr auto CWD_THREAD_LOCAL_INDEX = 3;
+        auto get_tls() noexcept -> char *
+        {
+            auto pcwd = reinterpret_cast<char *>(pvTaskGetThreadLocalStoragePointer(nullptr, CWD_THREAD_LOCAL_INDEX));
+            if (pcwd == nullptr) {
+                pcwd = new (std::nothrow) char[PATH_MAX + 1];
+                if (pcwd) {
+                    std::strncpy(pcwd, "/", PATH_MAX);
+                    vTaskSetThreadLocalStoragePointer(nullptr, CWD_THREAD_LOCAL_INDEX, pcwd);
+                }
+            }
+            return pcwd;
+        }
+    } // namespace
+    auto get_thread_local_cwd_path() noexcept -> std::string_view
+    {
+        return get_tls();
+    }
+    auto set_thread_cwd_path(std::string_view path) noexcept -> int
+    {
+        if (path.size() > PATH_MAX) {
+            return -ERANGE;
+        }
+        auto tls = get_tls();
+        if (!tls) {
+            return -ENOMEM;
+        }
+        else {
+            std::memcpy(tls, path.data(), path.size());
+            tls[path.size()] = '\0';
+            return 0;
+        }
+    }
+    auto cleanup_thread_local_cwd_mem() -> void
+    {
+        auto pcwd = reinterpret_cast<char *>(pvTaskGetThreadLocalStoragePointer(nullptr, CWD_THREAD_LOCAL_INDEX));
+        if (pcwd) {
+            delete[] pcwd;
+            vTaskSetThreadLocalStoragePointer(nullptr, CWD_THREAD_LOCAL_INDEX, nullptr);
+        }
+    }
+} // namespace purefs::fs::internal
diff --git a/module-vfs/include/internal/purefs/fs/directory_handle.hpp b/module-vfs/include/internal/purefs/fs/directory_handle.hpp
index a9d0bdd02b9c92e9039310655879e9096a025948..25c1458302aa0eb3bec484e75ed810b39b2c604f 100644
--- a/module-vfs/include/internal/purefs/fs/directory_handle.hpp
+++ b/module-vfs/include/internal/purefs/fs/directory_handle.hpp
@@ -10,8 +10,10 @@ namespace purefs::fs::internal
     class directory_handle
     {
       public:
+        directory_handle(int error, std::shared_ptr<mount_point> mount_point = nullptr)
+            : m_error(error), m_mount_point(mount_point)
+        {}
         directory_handle(const directory_handle &) = delete;
-        virtual ~directory_handle()                = delete;
         auto operator=(const directory_handle &) = delete;
         auto error(int error) noexcept -> void
         {
@@ -24,6 +26,6 @@ namespace purefs::fs::internal
 
       private:
         int m_error{};
-        std::weak_ptr<mount_point> m_mount_point;
+        const std::weak_ptr<mount_point> m_mount_point;
     };
 } // namespace purefs::fs::internal
diff --git a/module-vfs/include/internal/purefs/fs/file_handle.hpp b/module-vfs/include/internal/purefs/fs/file_handle.hpp
index 0e44e75b163d92c4998a26e85a63050e29ea16a2..d5a5fc993ce629e92a16fbfd4069679424beb1fb 100644
--- a/module-vfs/include/internal/purefs/fs/file_handle.hpp
+++ b/module-vfs/include/internal/purefs/fs/file_handle.hpp
@@ -14,6 +14,8 @@ namespace purefs::fs::internal
       public:
         file_handle(const file_handle &) = delete;
         virtual ~file_handle()           = default;
+        explicit file_handle(std::shared_ptr<mount_point> mp) : m_mount_point(mp)
+        {}
         [[nodiscard]] auto error() const noexcept
         {
             return m_error;
@@ -30,9 +32,13 @@ namespace purefs::fs::internal
         {
             return m_flags;
         }
-        std::weak_ptr<mount_point> m_mount_point;
+        [[nodiscard]] auto mntpoint() const noexcept
+        {
+            return m_mount_point;
+        }
 
       private:
+        const std::weak_ptr<mount_point> m_mount_point;
         int m_error{};
         int m_flags{};
     };
diff --git a/module-vfs/include/internal/purefs/utils/handle_mapper.hpp b/module-vfs/include/internal/purefs/fs/handle_mapper.hpp
similarity index 93%
rename from module-vfs/include/internal/purefs/utils/handle_mapper.hpp
rename to module-vfs/include/internal/purefs/fs/handle_mapper.hpp
index 7fc683c3d51d8738fd24d34690fd6d90da21a193..f11d91dd1e41103a73142c6beffee66a6f72fb9f 100644
--- a/module-vfs/include/internal/purefs/utils/handle_mapper.hpp
+++ b/module-vfs/include/internal/purefs/fs/handle_mapper.hpp
@@ -4,7 +4,7 @@
 #pragma once
 
 #include <vector>
-namespace purefs::utils::internal
+namespace purefs::fs::internal
 {
 
     template <typename T> class handle_mapper
@@ -44,4 +44,4 @@ namespace purefs::utils::internal
         data[result] = value;
         return result;
     }
-} // namespace purefs::utils::internal
+} // namespace purefs::fs::internal
diff --git a/module-vfs/include/internal/purefs/fs/mount_point.hpp b/module-vfs/include/internal/purefs/fs/mount_point.hpp
index 9f2201df02b049b42b6533dcb09d815bb78f194c..7717ddfd8a0be15b7d2d569cbaef4bf853cdd538 100644
--- a/module-vfs/include/internal/purefs/fs/mount_point.hpp
+++ b/module-vfs/include/internal/purefs/fs/mount_point.hpp
@@ -5,25 +5,43 @@
 #include <memory>
 #include <string>
 
-namespace purefs::blkdev
+namespace purefs::blkdev::internal
 {
-    class disk;
+    class disk_handle;
 }
 
 namespace purefs::fs
 {
-    class filesystem_operation;
+    class filesystem_operations;
 }
 
 namespace purefs::fs::internal
 {
     //! Mount point disk private structure
-    //! TODO fill the blanks
     class mount_point
     {
-        virtual ~mount_point() = default;
-        int device{-1};                                 //! Owning device
-        std::string mount_path;                         //! Mounted path
-        std::weak_ptr<filesystem_operation> filesystem; //! Filesystem operation
+      public:
+        mount_point(std::shared_ptr<blkdev::internal::disk_handle> diskh,
+                    std::string_view path,
+                    std::shared_ptr<filesystem_operations> fs)
+            : m_diskh(diskh), m_path(path), m_fs(fs)
+        {}
+        auto disk() const noexcept
+        {
+            return m_diskh;
+        }
+        auto mount_path() const noexcept
+        {
+            return m_path;
+        }
+        auto fs_ops() const noexcept
+        {
+            return m_fs;
+        }
+
+      private:
+        const std::weak_ptr<blkdev::internal::disk_handle> m_diskh;
+        const std::string_view m_path;                   //! Mounted path
+        const std::weak_ptr<filesystem_operations> m_fs; //! Filesystem operation
     };
 } // namespace purefs::fs::internal
diff --git a/module-vfs/include/internal/purefs/fs/thread_local_cwd.hpp b/module-vfs/include/internal/purefs/fs/thread_local_cwd.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..fde437601e400024090314db77a0da559426abb8
--- /dev/null
+++ b/module-vfs/include/internal/purefs/fs/thread_local_cwd.hpp
@@ -0,0 +1,12 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+
+#pragma once
+#include <string>
+
+namespace purefs::fs::internal
+{
+    auto get_thread_local_cwd_path() noexcept -> std::string_view;
+    auto set_thread_cwd_path(std::string_view path) noexcept -> int;
+    auto cleanup_thread_local_cwd_mem() -> void;
+} // namespace purefs::fs::internal
diff --git a/module-vfs/include/user/purefs/fs/filesystem.hpp b/module-vfs/include/user/purefs/fs/filesystem.hpp
index 42ac2c3770ded75a58cac9621f99bcccb2423e15..fc10fc30b08dc20a8ab3bbd894df5c997f58057e 100644
--- a/module-vfs/include/user/purefs/fs/filesystem.hpp
+++ b/module-vfs/include/user/purefs/fs/filesystem.hpp
@@ -6,18 +6,29 @@
 #include <memory>
 #include <list>
 #include <array>
+#include <mutex.hpp>
+#include <unordered_map>
+#include <map>
+#include <functional>
+#include <ctime>
+#include <purefs/fs/handle_mapper.hpp>
+#include <purefs/fs/file_handle.hpp>
+#include <purefs/fs/mount_point.hpp>
 
-namespace purefs::fs
+namespace purefs::blkdev
 {
+    class disk_manager;
+}
 
+namespace purefs::fs
+{
     /** This is the filesystem class layer
      * All methods can be called from the user thread
      * but generally those functions are for internal use for
      * example for newlib or glibc syscalls
      */
-    class filesystem_operation;
     struct statvfs;
-    struct timespec;
+    class filesystem_operations;
     namespace internal
     {
         class directory_handle;
@@ -26,7 +37,10 @@ namespace purefs::fs
     class filesystem
     {
       public:
+        static constexpr auto path_separator = '/';
         using fsdir                    = std::shared_ptr<internal::directory_handle>;
+        using fsfile                         = std::shared_ptr<internal::file_handle>;
+        explicit filesystem(std::shared_ptr<blkdev::disk_manager> diskmm);
         filesystem(const filesystem &) = delete;
         auto operator=(const filesystem &) = delete;
         /** Utility API */
@@ -35,7 +49,7 @@ namespace purefs::fs
          * @param[in] fops Filesystem operation structure
          * @return zero on sucess otherwise error
          */
-        auto register_filesystem(std::string_view fsname, std::shared_ptr<filesystem_operation> fops) -> int;
+        auto register_filesystem(std::string_view fsname, std::shared_ptr<filesystem_operations> fops) -> int;
         /** Unregister filesystem driver
          * @param[in] fsname Unique filesystem name for example fat
          * @return zero on success otherwise error
@@ -72,8 +86,8 @@ namespace purefs::fs
         auto write(int fd, const char *ptr, size_t len) noexcept -> ssize_t;
         auto read(int fd, char *ptr, size_t len) noexcept -> ssize_t;
         auto seek(int fd, off_t pos, int dir) noexcept -> off_t;
-        auto fstat(int fd, struct stat *st) noexcept -> int;
-        auto stat(std::string_view file, struct stat *st) noexcept -> int;
+        auto fstat(int fd, struct stat &st) noexcept -> int;
+        auto stat(std::string_view file, struct stat &st) noexcept -> int;
         auto link(std::string_view existing, std::string_view newlink) noexcept -> int;
         auto symlink(std::string_view existing, std::string_view newlink) noexcept -> int;
         auto unlink(std::string_view name) noexcept -> int;
@@ -91,13 +105,107 @@ namespace purefs::fs
         auto fsync(int fd) noexcept -> int;
         auto ioctl(std::string_view path, int cmd, void *arg) noexcept -> int;
         auto utimens(std::string_view path, std::array<timespec, 2> &tv) noexcept -> int;
-        auto flock(std::string_view path, int cmd) noexcept -> int;
-        auto isatty(std::string_view path) noexcept -> int;
+        auto flock(int fd, int cmd) noexcept -> int;
+        auto isatty(int fd) noexcept -> int;
 
         auto chmod(std::string_view path, mode_t mode) noexcept -> int;
         auto fchmod(int fd, mode_t mode) noexcept -> int;
 
-        auto getcwd() noexcept -> std::string;
+        auto getcwd() noexcept -> std::string_view;
         auto chdir(std::string_view name) noexcept -> int;
+
+      private:
+        /** Find the mount point object matching to the mount point path
+         * @param[in] path Absolute input path
+         * @return mount point object and the matching shortest path
+         */
+        auto find_mount_point(std::string_view path) const noexcept
+            -> std::tuple<std::shared_ptr<internal::mount_point>, size_t>;
+        /** Return absolute path from the relative path
+         * @param[in] path Unormalized path
+         * @return Full Normalized path
+         */
+        static auto absolute_path(std::string_view path) noexcept -> std::string;
+        /** Normalize full path
+         * @param[in] path Unnormalized full path
+         * @param[out] Normalized path
+         */
+        static auto normalize_path(std::string_view path) noexcept -> std::string;
+        /** Add handle to file descriptor
+         */
+        auto add_filehandle(fsfile file) noexcept -> int;
+        auto remove_filehandle(int fds) noexcept -> fsfile;
+        auto find_filehandle(int fds) const noexcept -> fsfile;
+
+      private:
+        template <class Base, class T, typename... Args>
+        inline auto invoke_fops(T Base::*method, int fds, Args &&... args)
+            -> decltype((static_cast<Base *>(nullptr)->*method)(0, std::forward<Args>(args)...))
+        {
+            auto fil = find_filehandle(fds);
+            if (!fil) {
+                return -EBADF;
+            }
+            else {
+                auto mp = fil->mntpoint().lock();
+                if (!mp) {
+                    return -ENOENT;
+                }
+                auto fsops = mp->fs_ops().lock();
+                if (!fsops) {
+                    return -EIO;
+                }
+                else {
+                    return (fsops.get()->*method)(fil, std::forward<Args>(args)...);
+                }
+            }
+        }
+
+        template <class Base, class T, typename... Args>
+        inline auto invoke_fops(T Base::*method, std::string_view path, Args &&... args) const
+            -> decltype((static_cast<Base *>(nullptr)->*method)(nullptr, {}, std::forward<Args>(args)...))
+        {
+            const auto abspath     = absolute_path(path);
+            auto [mountp, pathpos] = find_mount_point(abspath);
+            if (!mountp) {
+                return -ENOENT;
+            }
+            auto fsops = mountp->fs_ops().lock();
+            if (fsops)
+                return (fsops.get()->*method)(mountp, abspath, std::forward<Args>(args)...);
+            else
+                return -EIO;
+        }
+
+        template <class Base, class T, typename... Args>
+        inline auto invoke_fops_same_mp(T Base::*method,
+                                        std::string_view path,
+                                        std::string_view path2,
+                                        Args &&... args) const
+            -> decltype((static_cast<Base *>(nullptr)->*method)(nullptr, {}, {}, std::forward<Args>(args)...))
+        {
+            const auto abspath     = absolute_path(path);
+            const auto abspath2    = absolute_path(path2);
+            auto [mountp, pathpos] = find_mount_point(abspath);
+            if (!mountp) {
+                return -ENOENT;
+            }
+            if (path.compare(0, pathpos, path2, 0, pathpos) != 0) {
+                // Mount points are not the same
+                return -EXDEV;
+            }
+            auto fsops = mountp->fs_ops().lock();
+            if (fsops)
+                return (fsops.get()->*method)(mountp, abspath, abspath2, std::forward<Args>(args)...);
+            else
+                return -EIO;
+        }
+
+      private:
+        std::weak_ptr<blkdev::disk_manager> m_diskmm;
+        std::unordered_map<std::string, std::shared_ptr<filesystem_operations>> m_fstypes;
+        std::map<std::string, std::shared_ptr<internal::mount_point>> m_mounts;
+        internal::handle_mapper<fsfile> m_fds;
+        mutable cpp_freertos::MutexRecursive m_lock;
     };
 } // namespace purefs::fs
diff --git a/module-vfs/include/user/purefs/fs/filesystem_operation.hpp b/module-vfs/include/user/purefs/fs/filesystem_operation.hpp
deleted file mode 100644
index 7c2f3071dfb719deafc0cce6badddbab317e1c0d..0000000000000000000000000000000000000000
--- a/module-vfs/include/user/purefs/fs/filesystem_operation.hpp
+++ /dev/null
@@ -1,69 +0,0 @@
-// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
-// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
-
-#pragma once
-#include <string>
-#include <list>
-#include <tuple>
-#include <memory>
-
-namespace purefs::fs
-{
-    struct statvfs;
-    namespace internal
-    {
-        class file_handle;
-        class directory_handle;
-        class mount_point;
-    }; // namespace internal
-
-    /** Filesystem specific driver base class */
-    class filesystem_operation
-    {
-      public:
-        using fsfile                                       = std::shared_ptr<internal::file_handle>;
-        using fsdir                                        = std::shared_ptr<internal::directory_handle>;
-        using fsmount                                      = std::shared_ptr<internal::mount_point>;
-        filesystem_operation(const filesystem_operation &) = delete;
-        virtual ~filesystem_operation()                    = default;
-        auto operator=(const filesystem_operation &) = delete;
-        /** Allocate mount point class specify to the VFS
-         * @return Allocated mount point structure
-         */
-        virtual auto mount_prealloc() -> fsmount = 0;
-        virtual auto mount(fsmount mnt) noexcept -> int;
-        virtual auto umount(fsmount mnt) noexcept -> int                                  = 0;
-        virtual auto stat_vfs(std::string_view path, statvfs &stat) const noexcept -> int = 0;
-
-        /** Standard file access API */
-        virtual auto open(fsmount mnt, std::string_view path, int flags, int mode) noexcept -> fsfile          = 0;
-        virtual auto close(fsfile zfile) noexcept -> int                                                       = 0;
-        virtual auto write(fsfile zfile, const char *ptr, size_t len) noexcept -> ssize_t                      = 0;
-        virtual auto read(fsfile zfile, char *ptr, size_t len) noexcept -> ssize_t                             = 0;
-        virtual auto seek(fsfile zfile, off_t pos, int dir) noexcept -> off_t                                  = 0;
-        virtual auto fstat(fsfile zfile, struct stat *st) noexcept -> int                                      = 0;
-        virtual auto stat(fsmount mnt, std::string_view file, struct stat *st) noexcept -> int                 = 0;
-        virtual auto link(fsmount mnt, std::string_view existing, std::string_view newlink) noexcept -> int    = 0;
-        virtual auto symlink(fsmount mnt, std::string_view existing, std::string_view newlink) noexcept -> int = 0;
-        virtual auto unlink(fsmount mnt, std::string_view name) noexcept -> int                                = 0;
-        virtual auto rename(fsmount mnt, std::string_view oldname, std::string_view newname) noexcept -> int   = 0;
-        virtual auto mkdir(fsmount mnt, std::string_view path, int mode) noexcept -> int                       = 0;
-
-        /** Directory support API */
-        virtual auto diropen(fsmount mnt, std::string_view path) noexcept -> fsdir                         = 0;
-        virtual auto dirreset(fsdir dirstate) noexcept -> int                                              = 0;
-        virtual auto dirnext(fsdir dirstate, std::string &filename, struct stat &filestat) noexcept -> int = 0;
-        virtual auto dirclose(fsdir dirstate) noexcept -> int;
-
-        /** Other fops API */
-        virtual auto ftruncate(fsfile zfile, off_t len) noexcept -> int                                       = 0;
-        virtual auto fsync(fsfile zfile) noexcept -> int                                                      = 0;
-        virtual auto ioctl(fsfile zfile, int cmd, void *arg) noexcept -> int                                  = 0;
-        virtual auto utimens(fsmount mnt, std::string_view path, std::array<timespec, 2> &tv) noexcept -> int = 0;
-        virtual auto flock(fsfile zfile, int cmd) noexcept -> int                                             = 0;
-        virtual auto isatty(fsfile zfile) noexcept -> int                                                     = 0;
-
-        virtual auto chmod(fsmount mnt, std::string_view path, mode_t mode) noexcept -> int = 0;
-        virtual auto fchmod(fsfile zfile, mode_t mode) noexcept -> int                      = 0;
-    };
-} // namespace purefs::fs
diff --git a/module-vfs/include/user/purefs/fs/filesystem_operations.hpp b/module-vfs/include/user/purefs/fs/filesystem_operations.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..6740f5391b32db16bb04e70514593adc248fe0c8
--- /dev/null
+++ b/module-vfs/include/user/purefs/fs/filesystem_operations.hpp
@@ -0,0 +1,84 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+
+#pragma once
+#include <string>
+#include <list>
+#include <tuple>
+#include <memory>
+
+namespace purefs::blkdev::internal
+{
+    class disk_handle;
+}
+
+namespace purefs::fs
+{
+    struct statvfs;
+    namespace internal
+    {
+        class file_handle;
+        class directory_handle;
+        class mount_point;
+    }; // namespace internal
+
+    /** Filesystem specific driver base class */
+    class filesystem_operations
+    {
+      public:
+        using fsfile                                         = std::shared_ptr<internal::file_handle>;
+        using fsdir                                          = std::shared_ptr<internal::directory_handle>;
+        using fsmount                                        = std::shared_ptr<internal::mount_point>;
+        filesystem_operations(const filesystem_operations &) = delete;
+        virtual ~filesystem_operations()                     = default;
+        auto operator=(const filesystem_operations &) = delete;
+        /** Allocate mount point class specify to the VFS
+         * @return Allocated mount point structure
+         */
+        virtual auto mount_prealloc(std::shared_ptr<blkdev::internal::disk_handle> diskh, std::string_view path)
+            -> fsmount                                   = 0;
+        virtual auto mount(fsmount mnt) noexcept -> int  = 0;
+        virtual auto umount(fsmount mnt) noexcept -> int = 0;
+        virtual auto stat_vfs(fsmount mnt, std::string_view path, statvfs &stat) const noexcept -> int;
+
+        /** Standard file access API */
+        virtual auto open(fsmount mnt, std::string_view path, int flags, int mode) noexcept -> fsfile = 0;
+        virtual auto close(fsfile zfile) noexcept -> int                                              = 0;
+        virtual auto write(fsfile zfile, const char *ptr, size_t len) noexcept -> ssize_t             = 0;
+        virtual auto read(fsfile zfile, char *ptr, size_t len) noexcept -> ssize_t                    = 0;
+        virtual auto seek(fsfile zfile, off_t pos, int dir) noexcept -> off_t;
+        virtual auto fstat(fsfile zfile, struct stat &st) noexcept -> int;
+        virtual auto stat(fsmount mnt, std::string_view file, struct stat &st) noexcept -> int;
+        virtual auto link(fsmount mnt, std::string_view existing, std::string_view newlink) noexcept -> int;
+        virtual auto symlink(fsmount mnt, std::string_view existing, std::string_view newlink) noexcept -> int;
+        virtual auto unlink(fsmount mnt, std::string_view name) noexcept -> int;
+        virtual auto rename(fsmount mnt, std::string_view oldname, std::string_view newname) noexcept -> int;
+        virtual auto mkdir(fsmount mnt, std::string_view path, int mode) noexcept -> int;
+
+        /** Directory support API */
+        virtual auto diropen(fsmount mnt, std::string_view path) noexcept -> fsdir;
+        virtual auto dirreset(fsdir dirstate) noexcept -> int;
+        virtual auto dirnext(fsdir dirstate, std::string &filename, struct stat &filestat) -> int;
+        virtual auto dirclose(fsdir dirstate) noexcept -> int;
+
+        /** Other fops API */
+        virtual auto ftruncate(fsfile zfile, off_t len) noexcept -> int;
+        virtual auto fsync(fsfile zfile) noexcept -> int;
+        virtual auto ioctl(fsmount mnt, std::string_view path, int cmd, void *arg) noexcept -> int;
+        virtual auto utimens(fsmount mnt, std::string_view path, std::array<timespec, 2> &tv) noexcept -> int;
+        virtual auto flock(fsfile zfile, int cmd) noexcept -> int;
+        virtual auto isatty(fsfile zfile) noexcept -> int = 0;
+
+        virtual auto chmod(fsmount mnt, std::string_view path, mode_t mode) noexcept -> int;
+        virtual auto fchmod(fsfile zfile, mode_t mode) noexcept -> int;
+
+        /** Internal use */
+        auto mount_count() const noexcept
+        {
+            return m_mount_count;
+        }
+
+      private:
+        std::size_t m_mount_count{};
+    };
+} // namespace purefs::fs
diff --git a/module-vfs/src/purefs/fs/filesystem.cpp b/module-vfs/src/purefs/fs/filesystem.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..7f880336bd07b34c12c884f0a03df360d8012b1f
--- /dev/null
+++ b/module-vfs/src/purefs/fs/filesystem.cpp
@@ -0,0 +1,214 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+#include <purefs/fs/filesystem.hpp>
+#include <purefs/fs/filesystem_operations.hpp>
+#include <purefs/fs/mount_point.hpp>
+#include <purefs/blkdev/disk_manager.hpp>
+#include <purefs/fs/thread_local_cwd.hpp>
+#include <log/log.hpp>
+#include <split_sv.hpp>
+#include <errno.h>
+
+namespace purefs::fs
+{
+    filesystem::filesystem(std::shared_ptr<blkdev::disk_manager> diskmm) : m_diskmm(diskmm)
+    {}
+
+    auto filesystem::register_filesystem(std::string_view fsname, std::shared_ptr<filesystem_operations> fops) -> int
+    {
+        cpp_freertos::LockGuard _lck(m_lock);
+        const auto ret = m_fstypes.find(std::string(fsname));
+        if (ret != std::end(m_fstypes)) {
+            LOG_ERROR("Disc: %.*s already registered.", int(fsname.length()), fsname.data());
+            return -EEXIST;
+        }
+        else {
+            m_fstypes.emplace(std::make_pair(fsname, fops));
+            return {};
+        }
+    }
+
+    auto filesystem::unregister_filesystem(std::string_view fsname) -> int
+    {
+        cpp_freertos::LockGuard _lck(m_lock);
+        const auto it = m_fstypes.find(std::string(fsname));
+        if (it == std::end(m_fstypes)) {
+            LOG_ERROR("VFS: filesystem %.*s doesn't exists in manager.", int(fsname.length()), fsname.data());
+            return -ENOENT;
+        }
+        if (it->second->mount_count() > 0) {
+            LOG_ERROR("VFS: fileystem %.*s  is already used", int(fsname.length()), fsname.data());
+            return -EBUSY;
+        }
+        m_fstypes.erase(it);
+        return {};
+    }
+
+    auto filesystem::mount(std::string_view dev_or_part,
+                           std::string_view target,
+                           std::string_view fs_type,
+                           unsigned flags) -> int
+    {
+        // Sanity check input data
+        if (target.size() <= 1 || target[0] != '/') {
+            LOG_ERROR("VFS: Invalid target mountpoint path %.*s", int(target.length()), target.data());
+            return -EINVAL;
+        }
+        {
+            cpp_freertos::LockGuard _lock(m_lock);
+            const auto mpi = m_mounts.find(std::string(target));
+            if (mpi != std::end(m_mounts)) {
+                LOG_ERROR("VFS: mount point already exists %.*s", int(target.length()), target.data());
+                return -EBUSY;
+            }
+            const auto vsi = m_fstypes.find(std::string(fs_type));
+            if (vsi == std::end(m_fstypes)) {
+                LOG_ERROR("VFS: requested filesystem %.*s not registered", int(fs_type.length()), fs_type.data());
+            }
+            // Trying to open disk or part by manager
+            blkdev::disk_fd_t diskh;
+            {
+                auto disk_mgr = m_diskmm.lock();
+                if (disk_mgr) {
+                    diskh = disk_mgr->device_handle(dev_or_part);
+                }
+                else {
+                    LOG_ERROR("VFS: Unable to lock device manager");
+                    return -EIO;
+                }
+            }
+            if (diskh) {
+                const auto mnt_point = vsi->second->mount_prealloc(diskh, target);
+                const auto ret_mnt   = vsi->second->mount(mnt_point);
+                if (!ret_mnt)
+                    m_mounts.emplace(std::make_pair(target, mnt_point));
+                else
+                    return ret_mnt;
+            }
+        }
+        return {};
+    }
+
+    auto filesystem::umount(std::string_view mount_point) -> int
+    {
+        cpp_freertos::LockGuard _lck(m_lock);
+        auto mnti = m_mounts.find(std::string(mount_point));
+        if (mnti == std::end(m_mounts)) {
+            return -ENOENT;
+        }
+        auto fsops = mnti->second->fs_ops().lock();
+        if (!fsops) {
+            LOG_ERROR("Unable to lock filesystem operation");
+            return -EIO;
+        }
+        const auto umnt_ret = fsops->umount(mnti->second);
+        if (umnt_ret) {
+            return umnt_ret;
+        }
+        m_mounts.erase(mnti);
+        return {};
+    }
+
+    auto filesystem::read_mountpoints(std::list<std::string> &mountpoints) const -> int
+    {
+        cpp_freertos::LockGuard _lck(m_lock);
+        for (const auto &mntp : m_mounts) {
+            mountpoints.push_back(mntp.first);
+        }
+        return {};
+    }
+
+    auto filesystem::find_mount_point(std::string_view path) const noexcept
+        -> std::tuple<std::shared_ptr<internal::mount_point>, size_t>
+    {
+        size_t longest_match{};
+        std::shared_ptr<internal::mount_point> mount_pnt;
+        cpp_freertos::LockGuard _lck(m_lock);
+        for (const auto &mntp : m_mounts) {
+            const auto slen = mntp.first.size();
+            if ((slen < longest_match) || (slen > path.size())) {
+                continue;
+            }
+            if ((slen > 1) && (path[slen] != '/') && (path[slen] != '\0')) {
+                continue;
+            }
+            if (path.compare(0, slen, mntp.first) == 0) {
+                mount_pnt     = mntp.second;
+                longest_match = slen;
+            }
+        }
+        return std::make_tuple(mount_pnt, longest_match);
+    }
+
+    auto filesystem::absolute_path(std::string_view path) noexcept -> std::string
+    {
+        std::string ret{};
+        if (!path.empty() && path[0] == path_separator) {
+            ret.append(path);
+        }
+        else {
+            ret.append(internal::get_thread_local_cwd_path()).append("/").append(path);
+        }
+        return normalize_path(ret);
+    }
+
+    auto filesystem::normalize_path(std::string_view path) noexcept -> std::string
+    {
+        std::string ret;
+        auto paths = utils::split<std::list, std::string_view>(path, "/");
+        for (auto it = std::begin(paths); it != std::end(paths);) {
+            if (!it->compare(".")) {
+                it = paths.erase(it);
+            }
+            else if (!it->compare("..")) {
+                auto pit = it;
+                --pit;
+                if (pit != std::end(paths)) {
+                    it = paths.erase(pit);
+                    if (it != std::end(paths))
+                        it = paths.erase(it);
+                }
+                else {
+                    it = paths.erase(it);
+                }
+            }
+            else {
+                ++it;
+            }
+        }
+        for (auto ep : paths) {
+            if (!ep.empty()) {
+                ret.append("/").append(ep);
+            }
+        }
+        if (ret.empty())
+            ret.append("/");
+        return ret;
+    }
+
+    auto filesystem::add_filehandle(fsfile file) noexcept -> int
+    {
+        cpp_freertos::LockGuard _lck(m_lock);
+        return m_fds.insert(file);
+    }
+
+    auto filesystem::remove_filehandle(int fds) noexcept -> fsfile
+    {
+        cpp_freertos::LockGuard _lck(m_lock);
+        fsfile ret{};
+        if (m_fds.exists(fds)) {
+            ret = m_fds[fds];
+            m_fds.remove(fds);
+        }
+        return ret;
+    }
+    auto filesystem::find_filehandle(int fds) const noexcept -> fsfile
+    {
+        fsfile ret{};
+        cpp_freertos::LockGuard _lck(m_lock);
+        if (m_fds.exists(fds)) {
+            ret = m_fds[fds];
+        }
+        return ret;
+    }
+} // namespace purefs::fs
diff --git a/module-vfs/src/purefs/fs/filesystem_cwd.cpp b/module-vfs/src/purefs/fs/filesystem_cwd.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..b3064711825facac215b6fc69e4d6af0d8d441a5
--- /dev/null
+++ b/module-vfs/src/purefs/fs/filesystem_cwd.cpp
@@ -0,0 +1,32 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+
+#include <sys/types.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <purefs/fs/filesystem.hpp>
+#include <purefs/fs/thread_local_cwd.hpp>
+#include <unistd.h>
+
+namespace purefs::fs
+{
+    auto filesystem::getcwd() noexcept -> std::string_view
+    {
+        return internal::get_thread_local_cwd_path();
+    }
+    auto filesystem::chdir(std::string_view name) noexcept -> int
+    {
+        struct stat sts;
+        int ret;
+        ret = this->stat(name, sts);
+        if (ret) {
+            return ret;
+        }
+        if ((sts.st_mode & S_IFMT) != S_IFDIR) {
+            return -ENOTDIR;
+        }
+        const auto abspath = absolute_path(name);
+        ret                = internal::set_thread_cwd_path(abspath);
+        return ret;
+    }
+} // namespace purefs::fs
diff --git a/module-vfs/src/purefs/fs/filesystem_operations.cpp b/module-vfs/src/purefs/fs/filesystem_operations.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..235365e0fe46f3a2760f8a4ac5727fa59518bf7f
--- /dev/null
+++ b/module-vfs/src/purefs/fs/filesystem_operations.cpp
@@ -0,0 +1,104 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+#include <purefs/fs/filesystem_operations.hpp>
+#include <purefs/fs/directory_handle.hpp>
+
+#include <errno.h>
+
+namespace purefs::fs
+{
+
+    auto filesystem_operations::mount(fsmount mnt) noexcept -> int
+    {
+        ++m_mount_count;
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::umount(fsmount mnt) noexcept -> int
+    {
+        if (m_mount_count > 0) {
+            --m_mount_count;
+        }
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::stat_vfs(fsmount mntp, std::string_view path, statvfs &stat) const noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::seek(fsfile zfile, off_t pos, int dir) noexcept -> off_t
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::fstat(fsfile zfile, struct stat &st) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::stat(fsmount mnt, std::string_view file, struct stat &st) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::link(fsmount mnt, std::string_view existing, std::string_view newlink) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::symlink(fsmount mnt, std::string_view existing, std::string_view newlink) noexcept
+        -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::unlink(fsmount mnt, std::string_view name) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::rename(fsmount mnt, std::string_view oldname, std::string_view newname) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::mkdir(fsmount mnt, std::string_view path, int mode) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::diropen(fsmount mnt, std::string_view path) noexcept -> fsdir
+    {
+        return std::make_shared<internal::directory_handle>(-ENOTSUP);
+    }
+    auto filesystem_operations::dirreset(fsdir dirstate) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::dirnext(fsdir dirstate, std::string &filename, struct stat &filestat) -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::dirclose(fsdir dirstate) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::ftruncate(fsfile zfile, off_t len) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::fsync(fsfile zfile) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::ioctl(fsmount mnt, std::string_view path, int cmd, void *arg) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::utimens(fsmount mnt, std::string_view path, std::array<timespec, 2> &tv) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::flock(fsfile zfile, int cmd) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::chmod(fsmount mnt, std::string_view path, mode_t mode) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+    auto filesystem_operations::fchmod(fsfile zfile, mode_t mode) noexcept -> int
+    {
+        return -ENOTSUP;
+    }
+} // namespace purefs::fs
diff --git a/module-vfs/src/purefs/fs/filesystem_syscalls.cpp b/module-vfs/src/purefs/fs/filesystem_syscalls.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..5566660d215eb548378f125d126fa7bf80086fcf
--- /dev/null
+++ b/module-vfs/src/purefs/fs/filesystem_syscalls.cpp
@@ -0,0 +1,139 @@
+// Copyright (c) 2017-2020, Mudita Sp. z.o.o. All rights reserved.
+// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
+#include <purefs/fs/filesystem.hpp>
+#include <errno.h>
+#include <log/log.hpp>
+#include <purefs/fs/mount_point.hpp>
+#include <purefs/fs/filesystem_operations.hpp>
+#include <purefs/fs/file_handle.hpp>
+#include <purefs/fs/thread_local_cwd.hpp>
+
+namespace purefs::fs
+{
+    auto filesystem::stat_vfs(std::string_view path, statvfs &stat) const noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::stat_vfs, path, stat);
+    }
+
+    auto filesystem::stat(std::string_view file, struct stat &st) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::stat, file, st);
+    }
+
+    auto filesystem::unlink(std::string_view name) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::unlink, name);
+    }
+
+    auto filesystem::mkdir(std::string_view path, int mode) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::mkdir, path, mode);
+    }
+
+    auto filesystem::ioctl(std::string_view path, int cmd, void *arg) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::ioctl, path, cmd, arg);
+    }
+
+    auto filesystem::utimens(std::string_view path, std::array<timespec, 2> &tv) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::utimens, path, tv);
+    }
+
+    auto filesystem::flock(int fd, int cmd) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::flock, fd, cmd);
+    }
+
+    auto filesystem::isatty(int fd) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::isatty, fd);
+    }
+
+    auto filesystem::chmod(std::string_view path, mode_t mode) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::chmod, path, mode);
+    }
+
+    auto filesystem::close(int fd) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::close, fd);
+    }
+
+    auto filesystem::write(int fd, const char *ptr, size_t len) noexcept -> ssize_t
+    {
+        return invoke_fops(&filesystem_operations::write, fd, ptr, len);
+    }
+
+    auto filesystem::read(int fd, char *ptr, size_t len) noexcept -> ssize_t
+    {
+        return invoke_fops(&filesystem_operations::read, fd, ptr, len);
+    }
+
+    auto filesystem::seek(int fd, off_t pos, int dir) noexcept -> off_t
+    {
+        return invoke_fops(&filesystem_operations::seek, fd, pos, dir);
+    }
+
+    auto filesystem::fstat(int fd, struct stat &st) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::fstat, fd, st);
+    }
+
+    auto filesystem::ftruncate(int fd, off_t len) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::ftruncate, fd, len);
+    }
+
+    auto filesystem::fsync(int fd) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::fsync, fd);
+    }
+
+    auto filesystem::fchmod(int fd, mode_t mode) noexcept -> int
+    {
+        return invoke_fops(&filesystem_operations::fchmod, fd, mode);
+    }
+
+    auto filesystem::symlink(std::string_view existing, std::string_view newlink) noexcept -> int
+    {
+        return invoke_fops_same_mp(&filesystem_operations::symlink, existing, newlink);
+    }
+
+    auto filesystem::link(std::string_view existing, std::string_view newlink) noexcept -> int
+    {
+        return invoke_fops_same_mp(&filesystem_operations::link, existing, newlink);
+    }
+
+    auto filesystem::rename(std::string_view oldname, std::string_view newname) noexcept -> int
+    {
+        return invoke_fops_same_mp(&filesystem_operations::rename, oldname, newname);
+    }
+
+    auto filesystem::open(std::string_view path, int flags, int mode) noexcept -> int
+    {
+        const auto abspath     = absolute_path(path);
+        auto [mountp, pathpos] = find_mount_point(abspath);
+        if (!mountp) {
+            LOG_ERROR("VFS: Unable to find mount point");
+            return -ENOENT;
+        }
+        auto fsops = mountp->fs_ops().lock();
+        if (fsops) {
+            auto fh = fsops->open(mountp, abspath, flags, mode);
+            if (!fh) {
+                LOG_ERROR("VFS: Unable to get fops");
+                return -EBADF;
+            }
+            const auto err = fh->error();
+            if (err) {
+                return err;
+            }
+            return add_filehandle(fh);
+        }
+        else {
+            LOG_ERROR("VFS: Unable to lock fops");
+            return -EIO;
+        }
+    }
+} // namespace purefs::fs
diff --git a/module-vfs/targets/Target_Linux.cmake b/module-vfs/targets/Target_Linux.cmake
index d4a801321237ee32ddfbf2d9347c9f7a390e4873..8e9b87f462e4b13bcb88ea200242f001d7e1f1b9 100644
--- a/module-vfs/targets/Target_Linux.cmake
+++ b/module-vfs/targets/Target_Linux.cmake
@@ -3,6 +3,7 @@ set(BOARD_SOURCES
         ${CMAKE_CURRENT_SOURCE_DIR}/board/linux/free_rtos_custom/portable/common.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/board/linux/free_rtos_custom/portable/vfs.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/board/linux/purefs/src/blkdev/disk_image.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/board/linux/purefs/src/fs/thread_local_cwd.cpp
         CACHE INTERNAL ""
 )
 
diff --git a/module-vfs/targets/Target_RT1051.cmake b/module-vfs/targets/Target_RT1051.cmake
index 087ba05cfa150e5b49365db9576f6946509e39d0..eb52e3969bc3ade6eb4ccc81fc3a86901ac359c9 100644
--- a/module-vfs/targets/Target_RT1051.cmake
+++ b/module-vfs/targets/Target_RT1051.cmake
@@ -2,12 +2,13 @@ set(BOARD_SOURCES ${BOARD_SOURCES}
         src/newlib/vfs_io_syscalls.cpp
         src/newlib/vfs_internal_dirent.cpp
         src/newlib/HandleManager.cpp
+        board/rt1051/purefs/src/fs/thread_local_cwd.cpp
         CACHE INTERNAL ""
 )
 
 set(BOARD_DIR_INCLUDES ${BOARD_DIR_INCLUDES}
-
-
-        ${CMAKE_CURRENT_SOURCE_DIR}/board/rt1051 CACHE INTERNAL "")
+    ${CMAKE_CURRENT_SOURCE_DIR}/board/rt1051
+    CACHE INTERNAL ""
+)