This patch introduces a remount feature for the DFS, allowing for the
modification of mount parameters without unmounting the filesystem,
the remount functionality helps modify certain mount flags (like `MS_RDONLY`) without
requiring an unmount, providing more control over mounted filesystems in the system.
The updates is essential for user space init proc to cleanup the runtime
resource, ensuring clean handling of cached data and enhancing system
robustness during power down processing.
Changes:
- Defined new constants for remount flags in `dfs_fs.h`.
- Added the `dfs_remount()` function in `dfs_fs.c` to handle remount operations.
- Introduced a check for unsupported flags and handle error conditions such as invalid paths
or non-directory targets.
- Updated the `dfs_mnt` structure in `dfs_mnt.h` to include a read-only flag (`MNT_RDONLY`).
- The `dfs_remount()` function allows changing the read-only status of a mounted filesystem.
- Added `MNT_LAZY_UMNT` and `MNT_RDONLY` flags to `dfs_mnt` structure.
- Introduced `dfs_mnt_setflags` function for dynamic flag management.
- Updated `dfs_remount` to utilize `dfs_mnt_setflags` for flag setting.
- Enhanced unmount operations with `dfs_mnt_umount_iter` and lazy unmounting.
- Added `dfs_pcache_clean` to handle cache cleanup for read-only mounts.
- Improved error reporting in `dfs_umount` for better user feedback.
- Refactored `sys_mount` to streamline parameter handling and support remounts.
- Introduced `_cp_from_usr_string` helper for user-space string operations.
- Updated internal APIs to ensure consistency in reference count management.
Signed-off-by: Shell <smokewood@qq.com>
The patch introduces support for system reboot functionality and process teardown,
allowing for a clean shutdown and unmounting of the root filesystem. This is
necessary for ensuring a proper system shutdown process, especially when dealing
with resource cleanup and ensuring that all processes have exited before system
shutdown.
Changes:
- Added `lwp_teardown()` function to handle process cleanup and system teardown.
- Introduced `lwp_pid_wait_for_empty()` to wait for process ID table emptiness
before proceeding with shutdown.
- Updated `dfs_mnt_unref()` to trigger callbacks when unmounting a filesystem.
- Added new reboot types (`RB_AUTOBOOT`, `RB_POWER_OFF`) and implemented their
corresponding actions, including cleanup of processes and unmounting root
filesystem.
- Extended `sys_reboot()` to handle reboot and power off types with appropriate
callbacks for process and filesystem teardown.
- Introduced callback mechanism for root filesystem unmount notifications.
Signed-off-by: Shell <smokewood@qq.com>
This change introduces the `lwp_signal_kill_all` function, which allows a
signal to be sent to all processes in the system. The function iterates
over all PIDs and sends the specified signal to each process, except those
that are protected from signals. This enhancement provides a convenient way
to broadcast signals across all processes in the system.
Changes:
- Added `lwp_signal_kill_all` function in `lwp_signal.c` to broadcast a
signal to all processes by iterating over all PIDs using the existing
`lwp_pid_for_each` function.
- Introduced a new `kill_all_param` structure to encapsulate the signal
information needed for killing processes.
- Added internal `_kill_each` helper function for sending the signal to each
PID.
- Updated `lwp_signal.h` with the new function prototype for `lwp_signal_kill_all`.
- Modified `sys_kill` in `lwp_syscall.c` to call `lwp_signal_kill_all` when
a process is not specified.
Signed-off-by: Shell <smokewood@qq.com>
- `dbg_log` is a “NOT RECOMMENDED API”, convert the calling of this
API to LOG_x and remove this API.
- `dbg_here`/`dbg_enter`/`dbg_exit`: no one use these APIs, remove
them directly.
Signed-off-by: Chen Wang <unicorn_wang@outlook.com>
The `struct stat` object used inside mount(2) is uninitialized, which
can lead to undefined behavior during running
Changes:
- Set zero to buffer before calling to stat()
Signed-off-by: Shell <smokewood@qq.com>
This patch addresses a use-after-free (UAF) vulnerability in the
sys_mount. The issue occurred due to improper handling of memory
deallocation, which could lead to crashes or undefined behavior on user
request of mounting.
Changes made:
- Moved the `rt_free(copy_source)` function call to occur after the necessary
operations are completed, preventing premature deallocation of memory.
Signed-off-by: Shell <smokewood@qq.com>
This patch fixup the script execution capabilities on argv passing
and adds support for arguments larger than 4k.
According to POSIX, the script parameter is quiet different
from the current implementation. Especially on the way it inserts
the path of executables. At the end, when you execute a script
from `$PATH`, it always fails.
For the script, interpreter will be invoked with the following
arguments: `{interpreter [optional-arg] pathname arg...}`
where pathname is the pathname of the file specified as the first
argument of execve(), and arg... is the series of words pointed
to by the argv argument of execve(), starting at argv[1]. Note that
there is no way to get the argv[0] that was passed to the
execve() call.
The changes include:
- Separating argument, environment variable, and auxiliary vector
processing into a new lwp_args.c file.
- Fixing bugs in script argument processing and supporting arguments
larger than 4k.
- Updating lwp_execve to use the new argscopy function and removing
the old lwp_argscopy function.
- Making various modifications to lwp_load and elf_aux_fill to work
with the new argument processing.
- Removing unnecessary code related to dynamic loading and interpreter
scripts.
Signed-off-by: Shell <smokewood@qq.com>
Correct `sched_setaffinity()` to use the thread IDs (TIDs) instead of
process IDs (PIDs). The previous implementation used PIDs, which
caused issues since affinity settings need to be applied at the
thread level.
As the manual documented, the signature is:
> int sched_setaffinity(pid_t pid, size_t cpusetsize,
> const cpu_set_t *mask);
Yes, it's tricky, the identification passing in is called **'PID'**.
But when we talk about 'pid' from GNU libc, it's the **'task-id'**,
aka, `thread->tid` known in kernel.
Changes were made by updating the function signatures and logic in
`lwp.h`, `lwp_pid.c`, and `lwp_syscall.c` to accept TIDs. Specifically,
the `lwp_setaffinity` function and related internal functions now
operate using thread IDs and adjust thread affinity settings accordingly
Signed-off-by: Shell <smokewood@qq.com>
Prev implementation of lwp_new() including the create of lwp object
and the pid allocation. But not every lwp object need a pid.
So this patch split out the business of lwp_new() to improve the
maintainability.
Signed-off-by: Shell <smokewood@qq.com>
