Kernel library crate for xous
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xous-kernel/src/syscalls.rs

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use super::definitions::*;
/// Claims an interrupt and unmasks it immediately. The provided function will
/// be called from within an interrupt context, but using the ordinary privilege level of
/// the process.
///
/// # Errors
///
/// * **InterruptNotFound**: The specified interrupt isn't valid on this system
/// * **InterruptInUse**: The specified interrupt has already been claimed
#[allow(dead_code)]
pub fn sys_interrupt_claim(irq: usize, f: fn(usize)) -> Result<(), XousError> {
crate::irq::sys_interrupt_claim(irq, f)
}
/// Allocates pages of memory, equal to a total of `size
/// bytes. If a physical address is specified, then this
/// can be used to allocate regions such as memory-mapped I/O.
/// If a virtual address is specified, then the returned
/// pages are located at that address. Otherwise, they
/// are located at an unspecified offset.
///
/// # Errors
///
/// * **BadAlignment**: Either the physical or virtual addresses aren't page-aligned,
/// or the size isn't a multiple of the page width.
/// * **OutOfMemory**: A contiguous chunk of memory couldn't be found, or the system's
/// memory size has been exceeded.
// #[allow(dead_code)]
// pub fn sys_memory_allocate(
// phys: Option<MemoryAddress>,
// virt: Option<MemoryAddress>,
// size: MemorySize,
// ) -> Result<MemoryAddress, XousError> {
// crate::processtable::sys_memory_allocate(phys, virt, size)
// }
extern "Rust" {
/// Allocates kernel structures for a new process, and returns the new PID.
/// This removes `page_count` page tables from the calling process at `origin_address`
/// and places them at `target_address`.
///
/// If the process was created successfully, then the new PID is returned to
/// the calling process. The child is not automatically scheduled for running.
///
/// # Errors
///
/// * **BadAlignment**: `origin_address` or `target_address` were not page-aligned,
/// or `address_size` was not a multiple of the page address size.
/// * **OutOfMemory**: The kernel couldn't allocate memory for the new process.
#[allow(dead_code)]
pub fn sys_process_spawn(
origin_address: MemoryAddress,
target_address: MemoryAddress,
address_size: MemorySize,
) -> Result<XousPid, XousError>;
/// Pauses execution of the current thread and returns execution to the parent
/// process. This function may return at any time in the future, including immediately.
#[allow(dead_code)]
pub fn sys_process_yield();
/// Interrupts the current process and returns control to the parent process.
///
/// # Errors
///
/// * **ProcessNotFound**: The provided PID doesn't exist, or is not running on the given CPU.
#[allow(dead_code)]
pub fn sysi_process_suspend(pid: XousPid, cpu_id: XousCpuId) -> Result<(), XousError>;
/// Locks the system by disabling interrupts.
///
/// # Errors
///
/// * **InterruptNotFound**: The system is not currently executing an interrupt.
#[allow(dead_code)]
pub fn sys_lock() -> Result<(), XousError>;
/// Unlocks the system by enabling interrupts
///
/// # Errors
///
/// * **InterruptNotFound**: The system is not currently locked.
#[allow(dead_code)]
pub fn sys_unlock() -> Result<(), XousError>;
/// Returns the interrupt back to the operating system and masks it again.
/// This function is implicitly called when a process exits.
///
/// # Errors
///
/// * **InterruptNotFound**: The specified interrupt doesn't exist, or isn't assigned
/// to this process.
#[allow(dead_code)]
pub fn sys_interrupt_free(irq: usize) -> Result<(), XousError>;
/// Resumes a process using the given stack pointer. A parent could use
/// this function to implement multi-threading inside a child process, or
/// to create a task switcher.
///
/// To resume a process exactly where it left off, set `stack_pointer` to `None`.
/// This would be done in a very simple system that has no threads.
///
/// By default, at most three context switches can be made before the quantum
/// expires. To enable more, pass `additional_contexts`.
///
/// If no more contexts are available when one is required, then the child
/// automatically relinquishes its quantum.
///
/// # Returns
///
/// When this function returns, it provides a list of the processes and
/// stack pointers that are ready to be run. Three can fit as return values,
/// and additional context switches will be supplied in the slice of context
/// switches, if one is provided.
///
/// # Examples
///
/// If a process called `yield()`, or if its quantum expired normally, then
/// a single context is returned: The target thread, and its stack pointer.
///
/// If the child process called `client_send()` and ended up blocking due to
/// the server not being ready, then this would return no context switches.
/// This thread or process should not be scheduled to run.
///
/// If the child called `client_send()` and the server was ready, then the
/// server process would be run immediately. If the child process' quantum
/// expired while the server was running, then this function would return
/// a single context containing the PID of the server, and the stack pointer.
///
/// If the child called `client_send()` and the server was ready, then the
/// server process would be run immediately. If the server then finishes,
/// execution flow is returned to the child process. If the quantum then
/// expires, this would return two contexts: the server's PID and its stack
/// pointer when it called `client_reply()`, and the child's PID with its
/// current stack pointer.
///
/// If the server in turn called another server, and both servers ended up
/// returning to the child before the quantum expired, then there would be
/// three contexts on the stack.
///
/// # Errors
///
/// * **ProcessNotFound**: The requested process does not exist
/// * **ProcessNotChild**: The given process was not a child process, and
/// therefore couldn't be resumed.
/// * **ProcessTerminated**: The process has crashed.
#[allow(dead_code)]
pub fn sys_process_resume(
process_id: XousPid,
stack_pointer: Option<usize>,
additional_contexts: &Option<&[XousContext]>,
) -> Result<
(
Option<XousContext>,
Option<XousContext>,
Option<XousContext>,
),
XousError,
>;
/// Causes a process to terminate immediately.
///
/// It is recommended that this function only be called on processes that
/// have cleaned up after themselves, e.g. shut down any servers and
/// flushed any file descriptors.
///
/// # Errors
///
/// * **ProcessNotFound**: The requested process does not exist
/// * **ProcessNotChild**: The requested process is not our child process
#[allow(dead_code)]
pub fn sys_process_terminate(process_id: XousPid) -> Result<(), XousError>;
/// Equivalent to the Unix `sbrk` call. Adjusts the
/// heap size to be equal to the specified value. Heap
/// sizes start out at 0 bytes in new processes.
///
/// # Errors
///
/// * **OutOfMemory**: The region couldn't be extended.
#[allow(dead_code)]
pub fn sys_heap_resize(size: MemorySize) -> Result<(), XousError>;
///! Message Passing Functions
/// Create a new server with the given name. This enables other processes to
/// connect to this server to send messages. Only one server name may exist
/// on a system at a time.
///
/// # Errors
///
/// * **ServerExists**: A server has already registered with that name
/// * **InvalidString**: The name was not a valid UTF-8 string
#[allow(dead_code)]
pub fn sys_server_create(server_name: usize) -> Result<XousSid, XousError>;
/// Suspend the current process until a message is received. This thread will
/// block until a message is received.
///
/// # Errors
///
#[allow(dead_code)]
pub fn sys_server_receive(server_id: XousSid) -> Result<XousMessageReceived, XousError>;
/// Reply to a message received. The thread will be unblocked, and will be
/// scheduled to run sometime in the future.
///
/// If the message that we're responding to is a Memory message, then it should be
/// passed back directly to the destination without modification -- the actual contents
/// will be passed in the `out` address pointed to by the structure.
///
/// # Errors
///
/// * **ProcessTerminated**: The process we're replying to doesn't exist any more.
/// * **BadAddress**: The message didn't pass back all the memory it should have.
#[allow(dead_code)]
pub fn sys_server_reply(
destination: XousMessageSender,
message: XousMessage,
) -> Result<(), XousError>;
/// Look up a server name and connect to it.
///
/// # Errors
///
/// * **ServerNotFound**: No server is registered with that name.
#[allow(dead_code)]
pub fn sys_client_connect(server_name: usize) -> Result<XousConnection, XousError>;
/// Send a message to a server. This thread will block until the message is responded to.
/// If the message type is `Memory`, then the memory addresses pointed to will be
/// unavailable to this process until this function returns.
///
/// # Errors
///
/// * **ServerNotFound**: The server does not exist so the connection is now invalid
/// * **BadAddress**: The client tried to pass a Memory message using an address it doesn't own
/// * **Timeout**: The timeout limit has been reached
#[allow(dead_code)]
pub fn sys_client_send(
server: XousConnection,
message: XousMessage,
) -> Result<XousMessage, XousError>;
}