From 216ec44cf2fdc914ce38e3ab56eb3a8d82b54c77 Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Thu, 14 May 2026 16:59:56 +0200 Subject: Refactor resolve_path --- kernel/src/filesystem/vfs.cpp | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index f5d57be..52ffcc8 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -20,6 +20,7 @@ #include #include #include +#include namespace { @@ -165,11 +166,11 @@ namespace kernel::filesystem } } - auto vfs::resolve_path(std::string_view path) -> kstd::shared_ptr + auto vfs::resolve_path_internal(std::string_view path) -> std::pair, kstd::shared_ptr> { if (!path::is_valid_absolute_path(path)) { - return nullptr; + return {nullptr, nullptr}; } auto current_mount = m_mount_table.find_exact_mount("/"); @@ -225,7 +226,7 @@ namespace kernel::filesystem auto found_inode = current_fs->lookup(current_dentry->get_inode(), part.view()); if (!found_inode) { - return nullptr; + return {nullptr, nullptr}; } next_dentry = kstd::make_shared(current_dentry, found_inode, part.view()); @@ -246,7 +247,7 @@ namespace kernel::filesystem { if (symlink_counter++ > constants::symloop_max) { - return nullptr; + return {nullptr, nullptr}; } kstd::vector buffer(constants::symlink_max_path_length); @@ -269,9 +270,19 @@ namespace kernel::filesystem current_dentry = next_dentry; } + return {current_dentry, current_mount}; + } + + auto vfs::resolve_path(std::string_view path) -> kstd::shared_ptr + { + return resolve_path_internal(path).first; + } - return current_dentry; + auto vfs::find_mount(std::string_view path) -> kstd::shared_ptr + { + return resolve_path_internal(path).second; } + } // namespace kernel::filesystem namespace kernel::tests::filesystem::vfs -- cgit v1.2.3 From 146c40b22b834e4bf8d5e1d7256d3071f11d4bf9 Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Thu, 14 May 2026 17:33:14 +0200 Subject: Rename mount_point_dentry to target_dentry --- kernel/src/filesystem/vfs.cpp | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 52ffcc8..31ffa42 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -53,9 +53,9 @@ namespace kernel::filesystem auto device_fs = kstd::make_shared(); device_fs->mount(nullptr); - if (auto dev_mount_point_dentry = resolve_path("/dev")) + if (auto dev_target_dentry = resolve_path("/dev")) { - do_mount_internal(dev_mount_point_dentry, device_fs); + do_mount_internal(dev_target_dentry, device_fs); } else { @@ -98,13 +98,13 @@ namespace kernel::filesystem return operation_result::invalid_path; } - if (auto mount_point_dentry = resolve_path(target)) + if (auto target_dentry = resolve_path(target)) { if (auto source_dentry = resolve_path(source)) { if (auto fs = kernel::filesystem::filesystem::probe_and_mount(source_dentry->get_inode())) { - do_mount_internal(mount_point_dentry, fs); + do_mount_internal(target_dentry, fs); return operation_result::success; } return operation_result::invalid_filesystem; @@ -135,10 +135,10 @@ namespace kernel::filesystem return operation_result::mount_point_not_found; } - auto vfs::do_mount_internal(kstd::shared_ptr const & mount_point_dentry, - kstd::shared_ptr const & fs) -> void + auto vfs::do_mount_internal(kstd::shared_ptr const & target_dentry, kstd::shared_ptr const & fs) + -> void { - auto parent_mount_dentry = mount_point_dentry->find_mount_root_dentry(); + auto parent_mount_dentry = target_dentry->find_mount_root_dentry(); kstd::shared_ptr parent_mount = nullptr; if (parent_mount_dentry) { @@ -146,8 +146,8 @@ namespace kernel::filesystem } auto new_fs_root = - kstd::make_shared(mount_point_dentry->get_parent(), fs->root_inode(), mount_point_dentry->get_name()); - auto new_mount = kstd::make_shared(mount_point_dentry, new_fs_root, fs, parent_mount); + kstd::make_shared(target_dentry->get_parent(), fs->root_inode(), target_dentry->get_name()); + auto new_mount = kstd::make_shared(target_dentry, new_fs_root, fs, parent_mount); m_mount_table.add_mount(new_mount); } -- cgit v1.2.3 From 4cc120e7dba5c858a3a0f68b63e91e8d7b831701 Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Thu, 14 May 2026 18:03:44 +0200 Subject: Refactor do_mount_internal to use target_mount as parameter --- kernel/src/filesystem/vfs.cpp | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 31ffa42..c395e74 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -47,7 +47,8 @@ namespace kernel::filesystem root_fs->mount(nullptr); auto root_fs_root_dentry = kstd::make_shared(nullptr, root_fs->root_inode(), "/"); - m_mount_table.add_mount(kstd::make_shared(nullptr, root_fs_root_dentry, root_fs, nullptr)); + auto root_mount = kstd::make_shared(nullptr, root_fs_root_dentry, root_fs, nullptr); + m_mount_table.add_mount(root_mount); // mount devfs at /dev (inside rootfs, temporary, will be shadowed) auto device_fs = kstd::make_shared(); @@ -55,7 +56,7 @@ namespace kernel::filesystem if (auto dev_target_dentry = resolve_path("/dev")) { - do_mount_internal(dev_target_dentry, device_fs); + do_mount_internal(dev_target_dentry, root_mount, device_fs); } else { @@ -69,7 +70,7 @@ namespace kernel::filesystem { if (auto root_dentry = resolve_path("/")) { - do_mount_internal(root_dentry, boot_root_fs); + do_mount_internal(root_dentry, root_mount, boot_root_fs); graft_persistent_device_fs(device_fs); } } @@ -98,13 +99,15 @@ namespace kernel::filesystem return operation_result::invalid_path; } - if (auto target_dentry = resolve_path(target)) + auto [target_dentry, target_mount] = resolve_path_internal(target); + + if (target_dentry && target_mount) { if (auto source_dentry = resolve_path(source)) { if (auto fs = kernel::filesystem::filesystem::probe_and_mount(source_dentry->get_inode())) { - do_mount_internal(target_dentry, fs); + do_mount_internal(target_dentry, target_mount, fs); return operation_result::success; } return operation_result::invalid_filesystem; @@ -135,25 +138,20 @@ namespace kernel::filesystem return operation_result::mount_point_not_found; } - auto vfs::do_mount_internal(kstd::shared_ptr const & target_dentry, kstd::shared_ptr const & fs) + auto vfs::do_mount_internal(kstd::shared_ptr const & target_dentry, + kstd::shared_ptr const & target_mount, kstd::shared_ptr const & fs) -> void { - auto parent_mount_dentry = target_dentry->find_mount_root_dentry(); - kstd::shared_ptr parent_mount = nullptr; - if (parent_mount_dentry) - { - parent_mount = m_mount_table.find_exact_mount(parent_mount_dentry->get_absolute_path().view()); - } - auto new_fs_root = kstd::make_shared(target_dentry->get_parent(), fs->root_inode(), target_dentry->get_name()); - auto new_mount = kstd::make_shared(target_dentry, new_fs_root, fs, parent_mount); + auto new_mount = kstd::make_shared(target_dentry, new_fs_root, fs, target_mount); m_mount_table.add_mount(new_mount); } auto vfs::graft_persistent_device_fs(kstd::shared_ptr const & device_fs) -> void { - if (auto new_root_dentry = resolve_path("/")) + auto [new_root_dentry, root_mount] = resolve_path_internal("/"); + if (new_root_dentry && root_mount) { auto dev_dentry = new_root_dentry->find_child("dev"); if (!dev_dentry) @@ -162,7 +160,7 @@ namespace kernel::filesystem new_root_dentry->add_child(dev_dentry); } - do_mount_internal(dev_dentry, device_fs); + do_mount_internal(dev_dentry, root_mount, device_fs); } } -- cgit v1.2.3 From 963c926c68aac4606d80743aca8e7b052eee7efe Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Fri, 15 May 2026 11:42:33 +0200 Subject: Rename mount_table method from find_exact_mount to find_mount --- kernel/src/filesystem/vfs.cpp | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index c395e74..9b0440d 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -171,7 +171,7 @@ namespace kernel::filesystem return {nullptr, nullptr}; } - auto current_mount = m_mount_table.find_exact_mount("/"); + auto current_mount = m_mount_table.find_mount("/"); if (!current_mount) { kapi::system::panic("[FILESYSTEM] no root mount found."); @@ -232,7 +232,7 @@ namespace kernel::filesystem } else if (next_dentry->has_flag(dentry::dentry_flags::is_mount_point)) { - current_mount = m_mount_table.find_exact_mount(next_dentry->get_absolute_path().view()); + current_mount = m_mount_table.find_mount(next_dentry->get_absolute_path().view()); if (!current_mount) { kapi::system::panic("[FILESYSTEM] mount for dentry with mounted flag not found."); @@ -260,7 +260,7 @@ namespace kernel::filesystem if (path::is_valid_absolute_path(symbolic_link_path)) { - current_mount = m_mount_table.find_exact_mount("/"); + current_mount = m_mount_table.find_mount("/"); current_dentry = current_mount->get_root_dentry(); } continue; -- cgit v1.2.3 From 66d0e68376c9ad3e2b13f6ff8d999a0c85bda1a4 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Fri, 15 May 2026 15:47:06 +0200 Subject: renaming --- kernel/src/filesystem/vfs.cpp | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 9b0440d..77ae015 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -54,9 +54,9 @@ namespace kernel::filesystem auto device_fs = kstd::make_shared(); device_fs->mount(nullptr); - if (auto dev_target_dentry = resolve_path("/dev")) + if (auto dev_mount_point_dentry = resolve_path("/dev")) { - do_mount_internal(dev_target_dentry, root_mount, device_fs); + do_mount_internal(dev_mount_point_dentry, root_mount, device_fs); } else { @@ -99,15 +99,15 @@ namespace kernel::filesystem return operation_result::invalid_path; } - auto [target_dentry, target_mount] = resolve_path_internal(target); + auto [mount_point_dentry, mount_context] = resolve_path_internal(target); - if (target_dentry && target_mount) + if (mount_point_dentry && mount_context) { if (auto source_dentry = resolve_path(source)) { if (auto fs = kernel::filesystem::filesystem::probe_and_mount(source_dentry->get_inode())) { - do_mount_internal(target_dentry, target_mount, fs); + do_mount_internal(mount_point_dentry, mount_context, fs); return operation_result::success; } return operation_result::invalid_filesystem; @@ -138,26 +138,26 @@ namespace kernel::filesystem return operation_result::mount_point_not_found; } - auto vfs::do_mount_internal(kstd::shared_ptr const & target_dentry, - kstd::shared_ptr const & target_mount, kstd::shared_ptr const & fs) + auto vfs::do_mount_internal(kstd::shared_ptr const & mount_point_dentry, + kstd::shared_ptr const & parent_mount, kstd::shared_ptr const & fs) -> void { auto new_fs_root = - kstd::make_shared(target_dentry->get_parent(), fs->root_inode(), target_dentry->get_name()); - auto new_mount = kstd::make_shared(target_dentry, new_fs_root, fs, target_mount); + kstd::make_shared(mount_point_dentry->get_parent(), fs->root_inode(), mount_point_dentry->get_name()); + auto new_mount = kstd::make_shared(mount_point_dentry, new_fs_root, fs, parent_mount); m_mount_table.add_mount(new_mount); } auto vfs::graft_persistent_device_fs(kstd::shared_ptr const & device_fs) -> void { - auto [new_root_dentry, root_mount] = resolve_path_internal("/"); - if (new_root_dentry && root_mount) + auto [root_mount_point_dentry, root_mount] = resolve_path_internal("/"); + if (root_mount_point_dentry && root_mount) { - auto dev_dentry = new_root_dentry->find_child("dev"); + auto dev_dentry = root_mount_point_dentry->find_child("dev"); if (!dev_dentry) { - dev_dentry = kstd::make_shared(new_root_dentry, device_fs->root_inode(), "dev"); - new_root_dentry->add_child(dev_dentry); + dev_dentry = kstd::make_shared(root_mount_point_dentry, device_fs->root_inode(), "dev"); + root_mount_point_dentry->add_child(dev_dentry); } do_mount_internal(dev_dentry, root_mount, device_fs); -- cgit v1.2.3 From 1d647adb1ba20121eeb5c8e4470f48b2e972b3d4 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Fri, 15 May 2026 16:50:55 +0200 Subject: Mount can only be unmounted if no references are present, increment references on open file and decrement on close file --- kernel/src/filesystem/vfs.cpp | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 77ae015..3b3d6ff 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -89,7 +89,22 @@ namespace kernel::filesystem auto vfs::open(std::string_view path) -> kstd::shared_ptr { - return resolve_path(path); + auto [dentry, mount] = resolve_path_internal(path); + mount->increment_ref_count(); + return dentry; + } + + auto vfs::close(kstd::shared_ptr const & dentry) -> operation_result + { + if (auto mount = find_mount(dentry->get_absolute_path().view())) + { + if (mount->decrement_ref_count()) + { + return operation_result::success; + } + return operation_result::close_failed; + } + return operation_result::invalid_path; } auto vfs::do_mount(std::string_view source, std::string_view target) -> operation_result -- cgit v1.2.3 From 0e279db4e1b799c4db0cc7c714d57686e3de7089 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Fri, 15 May 2026 22:36:05 +0200 Subject: refactoring rootfs, no separate child management needed --- kernel/src/filesystem/vfs.cpp | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 3b3d6ff..67671e2 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -53,15 +53,7 @@ namespace kernel::filesystem // mount devfs at /dev (inside rootfs, temporary, will be shadowed) auto device_fs = kstd::make_shared(); device_fs->mount(nullptr); - - if (auto dev_mount_point_dentry = resolve_path("/dev")) - { - do_mount_internal(dev_mount_point_dentry, root_mount, device_fs); - } - else - { - kapi::system::panic("[FILESYSTEM] failed to resolve /dev for initial devfs mount."); - } + graft_persistent_device_fs(device_fs); // mount boot fs at / (shadows rootfs), re-graft devfs if (auto boot_device_dentry = resolve_path("/dev/ram0")) -- cgit v1.2.3 From 1f9fe3cf18b561749cfbdb2db8ab7572ddc40c03 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Fri, 15 May 2026 22:38:24 +0200 Subject: uniform interface for open and close --- kernel/src/filesystem/vfs.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 67671e2..de19d38 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -86,9 +86,9 @@ namespace kernel::filesystem return dentry; } - auto vfs::close(kstd::shared_ptr const & dentry) -> operation_result + auto vfs::close(std::string_view path) -> operation_result { - if (auto mount = find_mount(dentry->get_absolute_path().view())) + if (auto mount = find_mount(path)) { if (mount->decrement_ref_count()) { -- cgit v1.2.3 From 2396fe6174ec875ba12dc135ab18f84550c07e9a Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Fri, 15 May 2026 22:40:52 +0200 Subject: avoid nullptr access --- kernel/src/filesystem/vfs.cpp | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index de19d38..f6eae25 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -82,6 +82,10 @@ namespace kernel::filesystem auto vfs::open(std::string_view path) -> kstd::shared_ptr { auto [dentry, mount] = resolve_path_internal(path); + if (!dentry || !mount) + { + return nullptr; + } mount->increment_ref_count(); return dentry; } -- cgit v1.2.3 From efc7ba748b977a792188724c461852f01c111957 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Sat, 16 May 2026 14:05:49 +0200 Subject: add vfs tests --- kernel/src/filesystem/vfs.cpp | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index f6eae25..8636d0f 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -140,13 +140,12 @@ namespace kernel::filesystem { return operation_result::success; } - - if (remove_result == mount_table::operation_result::has_child_mounts) + else if (remove_result == mount_table::operation_result::mount_not_found) { - return operation_result::unmount_failed; + return operation_result::mount_point_not_found; } - return operation_result::mount_point_not_found; + return operation_result::unmount_failed; } auto vfs::do_mount_internal(kstd::shared_ptr const & mount_point_dentry, -- cgit v1.2.3