From 8550b6a1aacc2bfce733dcac7a44065b7e9116a1 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Sat, 2 May 2026 14:14:24 +0200 Subject: relative path support --- kernel/src/filesystem/vfs.cpp | 115 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 100 insertions(+), 15 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 5b454f6..41afad3 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -10,6 +10,8 @@ #include #include +#include +#include #include #include @@ -35,21 +37,38 @@ namespace kernel::filesystem auto vfs::init_internal() -> void { + // Mount rootfs at / as the temporary base auto root_fs = kstd::make_shared(); 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_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)); + // Mount devfs at /dev in rootfs (temporary, will be shadowed) auto device_fs = kstd::make_shared(); device_fs->mount(nullptr); - do_mount_internal("/dev", root_fs_root_dentry, device_fs); + auto dev_mount_point_dentry = resolve_path("/dev"); + if (!dev_mount_point_dentry) + { + kapi::system::panic("[FILESYSTEM] failed to resolve /dev for initial devfs mount."); + } + do_mount_internal("/dev", dev_mount_point_dentry, device_fs); - if (auto boot_device_dentry = resolve_path("/dev/ram0")) // TODO BA-FS26 better boot device detection + // Mount boot filesystem at / (will shadow rootfs) + if (auto boot_device_dentry = resolve_path("/dev/ram0")) { if (auto boot_root_fs = kernel::filesystem::filesystem::probe_and_mount(boot_device_dentry->get_inode())) { do_mount_internal("/", root_fs_root_dentry, boot_root_fs); + + // Resolve / to get the boot root dentry + if (auto boot_root_dentry = resolve_path("/")) + { + auto dev_dentry = kstd::make_shared(boot_root_dentry, device_fs->root_inode(), "dev"); + boot_root_dentry->add_child(dev_dentry); + + do_mount_internal("/dev", dev_dentry, device_fs); + } } } } @@ -117,33 +136,46 @@ namespace kernel::filesystem kstd::shared_ptr const & fs) -> void { auto parent_mount = m_mount_table.find_longest_prefix_mount(path); - auto new_fs_root = kstd::make_shared(mount_point_dentry, fs->root_inode()); + 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, path, parent_mount); m_mount_table.add_mount(new_mount); } auto vfs::resolve_path(std::string_view path) -> kstd::shared_ptr { - // TODO BA-FS26 implement full path resolution semantics. // TODO BA-FS26 better path validation // TODO BA-FS26 implement a path parser (maybe in libs?) and use it here and in do_mount - if (path.empty() || path.front() != '/') return nullptr; - // TODO BA-FS26 longest match in mount_table -> jump into final fs directly - // TODO BA-FS26 performance optimization first check mounted_flag O(1) then check mount_table O(n) - - auto best_mount = m_mount_table.find_longest_prefix_mount(path); - if (!best_mount) + auto current_mount = m_mount_table.find_longest_prefix_mount("/"); + if (!current_mount) { kapi::system::panic("[FILESYSTEM] no root mount found."); } - auto current_dentry = best_mount->root_dentry(); - auto current_fs = best_mount->get_filesystem(); + auto current_dentry = current_mount->root_dentry(); + kstd::vector resolved_parts{}; + + // TODO BA-FS26 remove again an get path out of the dentires instead of building it up again here + auto build_resolved_path = [&resolved_parts]() { + kstd::string resolved_path{"/"}; + + for (auto const & resolved_part : resolved_parts) + { + if (resolved_path.size() > 1) + { + resolved_path += '/'; + } + + resolved_path += resolved_part; + } - std::string_view remaining = path.substr(best_mount->get_mount_path().size()); + return resolved_path; + }; + + std::string_view remaining = path.substr(current_mount->get_mount_path().size()); auto path_parts = std::views::split(remaining, '/') | std::views::filter([](auto const & part) { return !part.empty(); }); @@ -152,9 +184,50 @@ namespace kernel::filesystem { std::string_view part_view{part}; + if (part_view == ".") + { + continue; + } + + if (part_view == "..") + { + if (!resolved_parts.empty()) + { + resolved_parts.pop_back(); + } + + auto parent_dentry = current_dentry->get_parent(); + + if (current_dentry == current_mount->root_dentry()) + { + // change the mount point + if (auto parent_mount = current_mount->get_parent_mount()) + { + current_mount = parent_mount; + current_dentry = current_dentry->get_parent(); + + if (!parent_dentry) + { + parent_dentry = current_mount->root_dentry(); + } + } + } + + if (!parent_dentry) + { + return nullptr; + } + + current_dentry = parent_dentry; + continue; + } + + resolved_parts.push_back(part_view); + auto next_dentry = current_dentry->find_child(part_view); if (!next_dentry) { + auto current_fs = current_mount->get_filesystem(); auto found_inode = current_fs->lookup(current_dentry->get_inode(), part_view); if (!found_inode) return nullptr; @@ -162,6 +235,18 @@ namespace kernel::filesystem next_dentry = kstd::make_shared(current_dentry, found_inode, part_view); current_dentry->add_child(next_dentry); } + else if (next_dentry->has_flag(dentry::dentry_flags::mounted)) + { + // change the mount point + // TODO BA-FS26 get resolved path out of the dentry... + current_mount = m_mount_table.find_longest_prefix_mount(build_resolved_path().view()); + if (!current_mount) + { + kapi::system::panic("[FILESYSTEM] mount for dentry with mounted flag not found."); + } + + next_dentry = current_mount->root_dentry(); + } current_dentry = next_dentry; } -- cgit v1.2.3 From d3c8b74020bfeee554394b7e41c58d5ddda6f396 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Sat, 2 May 2026 14:23:19 +0200 Subject: refactoring --- kernel/src/filesystem/vfs.cpp | 32 ++------------------------------ 1 file changed, 2 insertions(+), 30 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 41afad3..9a6625d 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -11,7 +11,6 @@ #include #include -#include #include #include @@ -156,25 +155,6 @@ namespace kernel::filesystem } auto current_dentry = current_mount->root_dentry(); - kstd::vector resolved_parts{}; - - // TODO BA-FS26 remove again an get path out of the dentires instead of building it up again here - auto build_resolved_path = [&resolved_parts]() { - kstd::string resolved_path{"/"}; - - for (auto const & resolved_part : resolved_parts) - { - if (resolved_path.size() > 1) - { - resolved_path += '/'; - } - - resolved_path += resolved_part; - } - - return resolved_path; - }; - std::string_view remaining = path.substr(current_mount->get_mount_path().size()); auto path_parts = @@ -191,11 +171,6 @@ namespace kernel::filesystem if (part_view == "..") { - if (!resolved_parts.empty()) - { - resolved_parts.pop_back(); - } - auto parent_dentry = current_dentry->get_parent(); if (current_dentry == current_mount->root_dentry()) @@ -222,8 +197,6 @@ namespace kernel::filesystem continue; } - resolved_parts.push_back(part_view); - auto next_dentry = current_dentry->find_child(part_view); if (!next_dentry) { @@ -237,9 +210,8 @@ namespace kernel::filesystem } else if (next_dentry->has_flag(dentry::dentry_flags::mounted)) { - // change the mount point - // TODO BA-FS26 get resolved path out of the dentry... - current_mount = m_mount_table.find_longest_prefix_mount(build_resolved_path().view()); + // TODO BA-FS26 really do it like this? or just call "get" without longes_prefix stuff + current_mount = m_mount_table.find_longest_prefix_mount(next_dentry->get_full_path().view()); if (!current_mount) { kapi::system::panic("[FILESYSTEM] mount for dentry with mounted flag not found."); -- cgit v1.2.3 From e74e56559ae99fd14715371ebceb2545f68008de Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Sat, 2 May 2026 14:24:46 +0200 Subject: add todos --- kernel/src/filesystem/vfs.cpp | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 9a6625d..a3da258 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -89,6 +89,7 @@ namespace kernel::filesystem auto vfs::do_mount(std::string_view source, std::string_view target) -> operation_result { + // TODO BA-FS26 better path validation if (target.empty() || target.front() != '/' || (target.size() > 1 && target.back() == '/')) { return operation_result::invalid_path; @@ -112,6 +113,7 @@ namespace kernel::filesystem auto vfs::unmount(std::string_view path) -> operation_result { + // TODO BA-FS26 better path validation if (path.empty() || path.front() != '/' || (path.size() > 1 && path.back() == '/')) { return operation_result::invalid_path; -- cgit v1.2.3 From 1269410c4c733ed38859b3e70713728afb273443 Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Sun, 3 May 2026 15:01:49 +0200 Subject: Use iterator in path resolution, start with symlink implementation --- kernel/src/filesystem/vfs.cpp | 40 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 37 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 a3da258..ba4f404 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -94,7 +94,7 @@ namespace kernel::filesystem { return operation_result::invalid_path; } - + // TODO BA-FS26 check if target is directory? if (auto mount_point_dentry = resolve_path(target)) { if (auto source_dentry = resolve_path(source)) @@ -162,9 +162,9 @@ namespace kernel::filesystem auto path_parts = std::views::split(remaining, '/') | std::views::filter([](auto const & part) { return !part.empty(); }); - for (auto const & part : path_parts) + for (auto it = path_parts.begin(); it != path_parts.end(); ++it) { - std::string_view part_view{part}; + std::string_view part_view{*it}; if (part_view == ".") { @@ -205,7 +205,9 @@ namespace kernel::filesystem auto current_fs = current_mount->get_filesystem(); auto found_inode = current_fs->lookup(current_dentry->get_inode(), part_view); if (!found_inode) + { return nullptr; + } next_dentry = kstd::make_shared(current_dentry, found_inode, part_view); current_dentry->add_child(next_dentry); @@ -222,6 +224,38 @@ namespace kernel::filesystem next_dentry = current_mount->root_dentry(); } + if (next_dentry->get_inode()->is_symbolic_link()) + { + // TODO BA-FS26 this for loop is ugly --> fix + kstd::string symlink_path = "halo"; + if (symlink_path.size() > 0 && symlink_path.front() == '/') + { + for (auto it2 = std::next(it); it2 != path_parts.end(); ++it2) + { + symlink_path += "/"; + symlink_path.append(std::string_view{*it2}); + } + return resolve_path(symlink_path.view()); + } + else + { + kstd::string combined; + for (auto it3 = path_parts.begin(); it3 != it; ++it3) + { + combined += "/"; + combined.append(std::string_view{*it3}); + } + combined += "/"; + combined += symlink_path; + for (auto it4 = std::next(it); it4 != path_parts.end(); ++it4) + { + combined += "/"; + combined.append(std::string_view{*it4}); + } + return resolve_path(combined.view()); + } + } + current_dentry = next_dentry; } -- cgit v1.2.3 From 7ff97f0fe861bb7382f41ecd4bab26cbb62b1f7d Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Mon, 4 May 2026 19:47:57 +0200 Subject: Resolve TODOs concerning path validation --- kernel/src/filesystem/vfs.cpp | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index ba4f404..8f48820 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -5,6 +5,7 @@ #include #include #include +#include #include #include @@ -89,12 +90,11 @@ namespace kernel::filesystem auto vfs::do_mount(std::string_view source, std::string_view target) -> operation_result { - // TODO BA-FS26 better path validation - if (target.empty() || target.front() != '/' || (target.size() > 1 && target.back() == '/')) + if (!kernel::filesystem::path::is_valid_path(source) || !kernel::filesystem::path::is_valid_path(target)) { return operation_result::invalid_path; } - // TODO BA-FS26 check if target is directory? + if (auto mount_point_dentry = resolve_path(target)) { if (auto source_dentry = resolve_path(source)) @@ -113,8 +113,7 @@ namespace kernel::filesystem auto vfs::unmount(std::string_view path) -> operation_result { - // TODO BA-FS26 better path validation - if (path.empty() || path.front() != '/' || (path.size() > 1 && path.back() == '/')) + if (!kernel::filesystem::path::is_valid_path(path)) { return operation_result::invalid_path; } @@ -145,11 +144,12 @@ namespace kernel::filesystem auto vfs::resolve_path(std::string_view path) -> kstd::shared_ptr { - // TODO BA-FS26 better path validation - // TODO BA-FS26 implement a path parser (maybe in libs?) and use it here and in do_mount - if (path.empty() || path.front() != '/') + if (!kernel::filesystem::path::is_valid_absolute_path(path)) + { return nullptr; + } + // TODO BA-FS26 refactor (get mount by path, no more prefix matching) auto current_mount = m_mount_table.find_longest_prefix_mount("/"); if (!current_mount) { @@ -157,10 +157,8 @@ namespace kernel::filesystem } auto current_dentry = current_mount->root_dentry(); - std::string_view remaining = path.substr(current_mount->get_mount_path().size()); - auto path_parts = - std::views::split(remaining, '/') | std::views::filter([](auto const & part) { return !part.empty(); }); + auto path_parts = kernel::filesystem::path::split(path); for (auto it = path_parts.begin(); it != path_parts.end(); ++it) { -- cgit v1.2.3 From d1e64340abb960c579651635d580660c12f94e6e Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Mon, 4 May 2026 20:31:58 +0200 Subject: Refactor path resolution, use vector and while instead of iterator and for-loop --- kernel/src/filesystem/vfs.cpp | 9 +++++++-- 1 file changed, 7 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 8f48820..c9939fa 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -12,7 +12,9 @@ #include #include +#include +#include #include #include #include @@ -159,10 +161,13 @@ namespace kernel::filesystem auto current_dentry = current_mount->root_dentry(); auto path_parts = kernel::filesystem::path::split(path); + kstd::vector path_parts_vector(path_parts.begin(), path_parts.end()); + std::ranges::reverse(path_parts_vector); - for (auto it = path_parts.begin(); it != path_parts.end(); ++it) + while (!path_parts_vector.empty()) { - std::string_view part_view{*it}; + std::string_view part_view{path_parts_vector.back()}; + path_parts_vector.pop_back(); if (part_view == ".") { -- cgit v1.2.3 From bddee0f0cb77eb247eceea18005dc575b433bb69 Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Mon, 4 May 2026 20:51:49 +0200 Subject: Implement symlink non-recursive --- kernel/src/filesystem/vfs.cpp | 41 +++++++++++++++-------------------------- 1 file changed, 15 insertions(+), 26 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index c9939fa..06d36ce 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -15,6 +15,7 @@ #include #include +#include #include #include #include @@ -229,33 +230,21 @@ namespace kernel::filesystem if (next_dentry->get_inode()->is_symbolic_link()) { - // TODO BA-FS26 this for loop is ugly --> fix - kstd::string symlink_path = "halo"; - if (symlink_path.size() > 0 && symlink_path.front() == '/') - { - for (auto it2 = std::next(it); it2 != path_parts.end(); ++it2) - { - symlink_path += "/"; - symlink_path.append(std::string_view{*it2}); - } - return resolve_path(symlink_path.view()); - } - else + // TODO BA-FS26 max symbolic link depth to prevent infinite loops + kstd::vector buffer(4096); // TODO BA-FS26 max symlink size? + auto const bytes_read = next_dentry->get_inode()->read(buffer.data(), 0, buffer.size()); + auto const symbolic_link_path = std::string_view{reinterpret_cast(buffer.data()), bytes_read}; + + auto symbolic_link_parts = kernel::filesystem::path::split(symbolic_link_path); + kstd::vector symbolic_link_parts_vector(symbolic_link_parts.begin(), symbolic_link_parts.end()); + std::ranges::reverse(symbolic_link_parts_vector); + + path_parts_vector.insert_range(path_parts_vector.end(), symbolic_link_parts_vector); + + if (kernel::filesystem::path::is_valid_absolute_path(symbolic_link_path)) { - kstd::string combined; - for (auto it3 = path_parts.begin(); it3 != it; ++it3) - { - combined += "/"; - combined.append(std::string_view{*it3}); - } - combined += "/"; - combined += symlink_path; - for (auto it4 = std::next(it); it4 != path_parts.end(); ++it4) - { - combined += "/"; - combined.append(std::string_view{*it4}); - } - return resolve_path(combined.view()); + current_mount = m_mount_table.find_longest_prefix_mount("/"); + next_dentry = current_mount->root_dentry(); } } -- cgit v1.2.3 From 2ab9d6ffbc4aad8ab3a393bd32191e3c07103c0a Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Tue, 5 May 2026 14:37:47 +0200 Subject: fix problem with string_view lifetime --- kernel/src/filesystem/vfs.cpp | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 06d36ce..03921df 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -167,15 +167,15 @@ namespace kernel::filesystem while (!path_parts_vector.empty()) { - std::string_view part_view{path_parts_vector.back()}; + auto part = path_parts_vector.back(); path_parts_vector.pop_back(); - if (part_view == ".") + if (part == ".") { continue; } - if (part_view == "..") + if (part == "..") { auto parent_dentry = current_dentry->get_parent(); @@ -203,17 +203,17 @@ namespace kernel::filesystem continue; } - auto next_dentry = current_dentry->find_child(part_view); + auto next_dentry = current_dentry->find_child(part.view()); if (!next_dentry) { auto current_fs = current_mount->get_filesystem(); - auto found_inode = current_fs->lookup(current_dentry->get_inode(), part_view); + auto found_inode = current_fs->lookup(current_dentry->get_inode(), part.view()); if (!found_inode) { return nullptr; } - next_dentry = kstd::make_shared(current_dentry, found_inode, part_view); + next_dentry = kstd::make_shared(current_dentry, found_inode, part.view()); current_dentry->add_child(next_dentry); } else if (next_dentry->has_flag(dentry::dentry_flags::mounted)) @@ -244,8 +244,9 @@ namespace kernel::filesystem if (kernel::filesystem::path::is_valid_absolute_path(symbolic_link_path)) { current_mount = m_mount_table.find_longest_prefix_mount("/"); - next_dentry = current_mount->root_dentry(); + current_dentry = current_mount->root_dentry(); } + continue; } current_dentry = next_dentry; -- cgit v1.2.3 From b6cc02c3bac002ebac8e6ba734b00f0e60b24778 Mon Sep 17 00:00:00 2001 From: Marcel Braun Date: Tue, 5 May 2026 16:05:48 +0200 Subject: Add check for max symlink count --- kernel/src/filesystem/vfs.cpp | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 03921df..e6d9241 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -1,5 +1,6 @@ #include +#include #include #include #include @@ -93,7 +94,7 @@ namespace kernel::filesystem auto vfs::do_mount(std::string_view source, std::string_view target) -> operation_result { - if (!kernel::filesystem::path::is_valid_path(source) || !kernel::filesystem::path::is_valid_path(target)) + if (!path::is_valid_path(source) || !path::is_valid_path(target)) { return operation_result::invalid_path; } @@ -116,7 +117,7 @@ namespace kernel::filesystem auto vfs::unmount(std::string_view path) -> operation_result { - if (!kernel::filesystem::path::is_valid_path(path)) + if (!path::is_valid_path(path)) { return operation_result::invalid_path; } @@ -147,7 +148,7 @@ namespace kernel::filesystem auto vfs::resolve_path(std::string_view path) -> kstd::shared_ptr { - if (!kernel::filesystem::path::is_valid_absolute_path(path)) + if (!path::is_valid_absolute_path(path)) { return nullptr; } @@ -161,10 +162,12 @@ namespace kernel::filesystem auto current_dentry = current_mount->root_dentry(); - auto path_parts = kernel::filesystem::path::split(path); + auto path_parts = path::split(path); kstd::vector path_parts_vector(path_parts.begin(), path_parts.end()); std::ranges::reverse(path_parts_vector); + auto symlink_counter = 0uz; + while (!path_parts_vector.empty()) { auto part = path_parts_vector.back(); @@ -230,18 +233,22 @@ namespace kernel::filesystem if (next_dentry->get_inode()->is_symbolic_link()) { - // TODO BA-FS26 max symbolic link depth to prevent infinite loops - kstd::vector buffer(4096); // TODO BA-FS26 max symlink size? + if (symlink_counter++ > constants::symloop_max) + { + return nullptr; + } + + kstd::vector buffer(constants::symlink_max_path_length); auto const bytes_read = next_dentry->get_inode()->read(buffer.data(), 0, buffer.size()); auto const symbolic_link_path = std::string_view{reinterpret_cast(buffer.data()), bytes_read}; - auto symbolic_link_parts = kernel::filesystem::path::split(symbolic_link_path); + auto symbolic_link_parts = path::split(symbolic_link_path); kstd::vector symbolic_link_parts_vector(symbolic_link_parts.begin(), symbolic_link_parts.end()); std::ranges::reverse(symbolic_link_parts_vector); path_parts_vector.insert_range(path_parts_vector.end(), symbolic_link_parts_vector); - if (kernel::filesystem::path::is_valid_absolute_path(symbolic_link_path)) + if (path::is_valid_absolute_path(symbolic_link_path)) { current_mount = m_mount_table.find_longest_prefix_mount("/"); current_dentry = current_mount->root_dentry(); -- cgit v1.2.3 From 265ac82029665921bd95d74411682968ee0d4ada Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Tue, 5 May 2026 19:41:50 +0200 Subject: refactoring do_mount_internal (retrieve path from dentry), handle .. correctly in relative path --- kernel/src/filesystem/vfs.cpp | 29 +++++++++++++++-------------- 1 file changed, 15 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 e6d9241..4defc81 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -56,14 +56,14 @@ namespace kernel::filesystem { kapi::system::panic("[FILESYSTEM] failed to resolve /dev for initial devfs mount."); } - do_mount_internal("/dev", dev_mount_point_dentry, device_fs); + do_mount_internal(dev_mount_point_dentry, device_fs); // Mount boot filesystem at / (will shadow rootfs) if (auto boot_device_dentry = resolve_path("/dev/ram0")) { if (auto boot_root_fs = kernel::filesystem::filesystem::probe_and_mount(boot_device_dentry->get_inode())) { - do_mount_internal("/", root_fs_root_dentry, boot_root_fs); + do_mount_internal(root_fs_root_dentry, boot_root_fs); // Resolve / to get the boot root dentry if (auto boot_root_dentry = resolve_path("/")) @@ -71,7 +71,7 @@ namespace kernel::filesystem auto dev_dentry = kstd::make_shared(boot_root_dentry, device_fs->root_inode(), "dev"); boot_root_dentry->add_child(dev_dentry); - do_mount_internal("/dev", dev_dentry, device_fs); + do_mount_internal(dev_dentry, device_fs); } } } @@ -105,7 +105,7 @@ namespace kernel::filesystem { if (auto fs = kernel::filesystem::filesystem::probe_and_mount(source_dentry->get_inode())) { - do_mount_internal(target, mount_point_dentry, fs); + do_mount_internal(mount_point_dentry, fs); return operation_result::success; } return operation_result::invalid_filesystem; @@ -136,13 +136,15 @@ namespace kernel::filesystem return operation_result::mount_point_not_found; } - auto vfs::do_mount_internal(std::string_view path, kstd::shared_ptr const & mount_point_dentry, + auto vfs::do_mount_internal(kstd::shared_ptr const & mount_point_dentry, kstd::shared_ptr const & fs) -> void { - auto parent_mount = m_mount_table.find_longest_prefix_mount(path); + auto mount_path = mount_point_dentry->get_full_path(); + + auto parent_mount = m_mount_table.find_longest_prefix_mount(mount_path.view()); 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, path, parent_mount); + auto new_mount = kstd::make_shared(mount_point_dentry, new_fs_root, fs, mount_path.view(), parent_mount); m_mount_table.add_mount(new_mount); } @@ -188,16 +190,15 @@ namespace kernel::filesystem if (auto parent_mount = current_mount->get_parent_mount()) { current_mount = parent_mount; - current_dentry = current_dentry->get_parent(); + current_dentry = parent_dentry; + } - if (!parent_dentry) - { - parent_dentry = current_mount->root_dentry(); - } + if (!parent_dentry) + { + parent_dentry = current_mount->root_dentry(); } } - - if (!parent_dentry) + else if (!parent_dentry) { return nullptr; } -- cgit v1.2.3 From b7fba373341dd44b53642d7233396efbef4526b2 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Tue, 5 May 2026 20:07:37 +0200 Subject: avoid to traverse back over the root --- kernel/src/filesystem/vfs.cpp | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 4defc81..7f21a5c 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -186,22 +186,17 @@ namespace kernel::filesystem if (current_dentry == current_mount->root_dentry()) { - // change the mount point - if (auto parent_mount = current_mount->get_parent_mount()) + if (current_mount->get_mount_path() == "/") { - current_mount = parent_mount; - current_dentry = parent_dentry; + continue; } - if (!parent_dentry) + if (auto parent_mount = current_mount->get_parent_mount()) { - parent_dentry = current_mount->root_dentry(); + current_mount = parent_mount; + current_dentry = parent_dentry; } } - else if (!parent_dentry) - { - return nullptr; - } current_dentry = parent_dentry; continue; -- cgit v1.2.3 From 7414148b662a33cf6c69f89b7b0c3162f6880d6c Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Tue, 5 May 2026 20:33:28 +0200 Subject: refactoring mount_table lookup --- kernel/src/filesystem/vfs.cpp | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 7f21a5c..19f5f48 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -41,7 +41,6 @@ namespace kernel::filesystem auto vfs::init_internal() -> void { - // Mount rootfs at / as the temporary base auto root_fs = kstd::make_shared(); root_fs->mount(nullptr); @@ -140,8 +139,8 @@ namespace kernel::filesystem kstd::shared_ptr const & fs) -> void { auto mount_path = mount_point_dentry->get_full_path(); - auto parent_mount = m_mount_table.find_longest_prefix_mount(mount_path.view()); + 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, mount_path.view(), parent_mount); @@ -156,7 +155,7 @@ namespace kernel::filesystem } // TODO BA-FS26 refactor (get mount by path, no more prefix matching) - auto current_mount = m_mount_table.find_longest_prefix_mount("/"); + auto current_mount = m_mount_table.find_exact_mount("/"); if (!current_mount) { kapi::system::panic("[FILESYSTEM] no root mount found."); @@ -217,8 +216,7 @@ namespace kernel::filesystem } else if (next_dentry->has_flag(dentry::dentry_flags::mounted)) { - // TODO BA-FS26 really do it like this? or just call "get" without longes_prefix stuff - current_mount = m_mount_table.find_longest_prefix_mount(next_dentry->get_full_path().view()); + current_mount = m_mount_table.find_exact_mount(next_dentry->get_full_path().view()); if (!current_mount) { kapi::system::panic("[FILESYSTEM] mount for dentry with mounted flag not found."); @@ -246,7 +244,7 @@ namespace kernel::filesystem if (path::is_valid_absolute_path(symbolic_link_path)) { - current_mount = m_mount_table.find_longest_prefix_mount("/"); + current_mount = m_mount_table.find_exact_mount("/"); current_dentry = current_mount->root_dentry(); } continue; -- cgit v1.2.3 From 7ccfa26a3dde4d4266f8c59f4e3de8bd6f760059 Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Tue, 5 May 2026 21:17:23 +0200 Subject: small refactoring, add todo --- kernel/src/filesystem/vfs.cpp | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index 19f5f48..b84f690 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -139,6 +139,7 @@ namespace kernel::filesystem kstd::shared_ptr const & fs) -> void { auto mount_path = mount_point_dentry->get_full_path(); + // TODO BA-FS26 refactoring, implement dentry lookup to get the parent mount... auto parent_mount = m_mount_table.find_longest_prefix_mount(mount_path.view()); auto new_fs_root = -- cgit v1.2.3 From 870039d48d28f479eea88c7548b8d2b2a28c09bc Mon Sep 17 00:00:00 2001 From: Lukas Oesch Date: Tue, 5 May 2026 21:18:48 +0200 Subject: add mount table find_exact_mount tests, remove todo --- kernel/src/filesystem/vfs.cpp | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel/src/filesystem/vfs.cpp') diff --git a/kernel/src/filesystem/vfs.cpp b/kernel/src/filesystem/vfs.cpp index b84f690..519550b 100644 --- a/kernel/src/filesystem/vfs.cpp +++ b/kernel/src/filesystem/vfs.cpp @@ -155,7 +155,6 @@ namespace kernel::filesystem return nullptr; } - // TODO BA-FS26 refactor (get mount by path, no more prefix matching) auto current_mount = m_mount_table.find_exact_mount("/"); if (!current_mount) { -- cgit v1.2.3