diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/syscall.md | 120 |
1 files changed, 100 insertions, 20 deletions
diff --git a/doc/syscall.md b/doc/syscall.md index 70f0570..10f8eb5 100644 --- a/doc/syscall.md +++ b/doc/syscall.md @@ -157,11 +157,11 @@ Successful retypes return 0. ### JOVE_OBJ_OBJDIR -| Syscall | Target Permissions | -|------------------------|--------------------------------------| -| SYSCALL_OBJDIR_OBJTYPE | JOVE_PERM_READ | -| SYSCALL_OBJDIR_UNTYPE | JOVE_PERM_WRITE <br>JOVE_PERM_MUTATE | -| SYSCALL_OBJDIR_SEND | JOVE_PERM_MUTATE | +| Syscall | Target Permissions | Subject Permissions | +|------------------------|--------------------|-----------------------------------| +| SYSCALL_OBJDIR_OBJTYPE | JOVE_PERM_READ | | +| SYSCALL_OBJDIR_SWAP | JOVE_PERM_WRITE | JOVE_PERM_WRITE | +| SYSCALL_OBJDIR_LINK | | JOVE_PERM_WRITE, JOVE_PERM_MUTATE | #### SYSCALL_OBJDIR_OBJTYPE @@ -175,17 +175,45 @@ If the message is too small to hold the payload, the kernel will return `-ETOOSM If the entry index exceeds `JOVE_OBJDIR_ENTRIES`, the kernel returns `-EOOB`. -#### SYSCALL_OBJDIR_UNTYPE -Converts the target object to an untyped object if possible. +#### SYSCALL_OBJDIR_SWAP -| Data | Entry Index | -|--------------|-------------| -| Size (bytes) | 2 | +Exchanges an object at the given entry index with the object at a given path. + +| Data | Entry Index | Other Path Length | Other Path | +|--------------|------------------------|------------------------|-----------------------------------------| +| Size (bytes) | sizeof(objpath_part_t) | sizeof(objpath_part_t) | other_path_len * sizeof(objpath_part_t) | + +If the entry index exceeds `JOVE_OBJDIR_ENTRIES`, the kernel will return `-EOOB`. + +If the other object does not point to an object, the kernel will return `-EBADPATH`. + +If the other object's parent directory does not have `JOVE_PERM_WRITE` permissions, the kernel will return `-EPERM`. + +Successful swaps will return 0. + + +#### SYSCALL_OBJDIR_LINK + +Copies an existing `JOVE_OBJ_LINK` object at a given entry into the passed object path. -If the target object does not have underlying memory, the kernel will replace the object with `JOVE_OBJ_NONE`. +Each copy increments the refcount. -If the target object has underlying memory, the kernel will replace the object with `JOVE_OBJ_UNTYPED`. +Permissions are inherited from the existing link. + +| Data | Entry Index | Other Path Length | Other Path | +|--------------|------------------------|------------------------|-----------------------------------------| +| Size (bytes) | sizeof(objpath_part_t) | sizeof(objpath_part_t) | other_path_len * sizeof(objpath_part_t) | + +If the entry index exceeds `JOVE_OBJDIR_ENTRIES`, the kernel will return `-EOOB`. + +If the other object does not point to an object, the kernel will return `-EBADPATH`. + +If the other object is not `JOVE_OBJ_NONE`, the kernel will return `-EFULL`. + +If the other object does not have `JOVE_PERM_WRITE | JOVE_PERM_MUTATE`, the kernel will return `-EPERM`. + +Successful links return 0. ### JOVE_OBJ_PAGEDIR @@ -341,12 +369,14 @@ Successful unmapping returns `0`. ### JOVE_OBJ_PCB -| Syscall | Target Permissions | Subject Permissions | -|-------------------|--------------------|---------------------| -| SYSCALL_PCB_PID | JOVE_PERM_READ | | -| SYSCALL_PCB_YIELD | JOVE_PERM_WRITE | | -| SYSCALL_PCB_SEND | JOVE_PERM_MUTATE | JOVE_PERM_MUTATE | -| SYSCALL_PCB_RECV | JOVE_PERM_MUTATE | JOVE_PERM_MUTATE | +| Syscall | Target Permissions | Subject Permissions | +|-------------------|-----------------------------------|-----------------------------------| +| SYSCALL_PCB_PID | JOVE_PERM_READ | | +| SYSCALL_PCB_YIELD | JOVE_PERM_WRITE | | +| SYSCALL_PCB_SEND | JOVE_PERM_MUTATE | JOVE_PERM_MUTATE | +| SYSCALL_PCB_RECV | JOVE_PERM_MUTATE | JOVE_PERM_MUTATE | +| SYSCALL_PCB_SWAP | JOVE_PERM_MUTATE | JOVE_PERM_MUTATE | +| SYSCALL_PCB_STACK | JOVE_PERM_WRITE, JOVE_PERM_MUTATE | JOVE_PERM_WRITE, JOVE_PERM_MUTATE | #### SYSCALL_PCB_YIELD @@ -358,7 +388,7 @@ Yields control to the specified process. If the yield target = `0`, the scheduler will determine the next process. -If the yield target does not exist, the kernel will return `-ENOPROC`. +If the yield target does not exist, the kernel will return `-EBADPROC`. #### SYSCALL_PCB_SEND @@ -400,16 +430,66 @@ Destination object is locked until the timeout expires or an object is placed in |--------------|-----------------|-------------------|------------------|-------------------| | Size (bytes) | sizeof(pid_t) | sizeof(uintmax_t) | 2 | 2 * dest_path_len | -If the specified pid does not correspond to a process, the kernel will return `-ENOPROC`. +If the specified pid does not correspond to a process, the kernel will return `-EBADPROC`. If the destination path does not correspond to a `JOVE_OBJ_NONE` object, the kernel will return `-EFULL`. If the destination path does not have the `JOVE_PERM_MUTATE` permission, the kernel will return `-EPERM`. +If the blocking timeout expires and an object was not received, the kernel will return `-ETIMEOUT`. + Recieved messages will be sent to the specified destination path. Successful retrieval returns `0`. +#### SYSCALL_PCB_SWAP + +Tries to send an object through the PCB mailbox, then tries to recieve an object back. + +Blocks on send until send timeout expires or returns early if mailbox is full and send timeout == 0. + +Blocks on recieve until recieve timeout expires or returns early if mailbox is empty and recieve timeout == 0. + +Destination object is locked until the timeout expires or an object is placed in the destination path. + +| Data | Target Process | Send Timeout | Recieve Timeout | Subject Path Length | Subject Path | +|--------------|----------------|-------------------|--------------------|---------------------|-------------------| +| Size (bytes) | sizeof(pid_t) | sizeof(uintmax_t) | sizeof(uintmax_t) | 2 | 2 * dest_path_len | + +If the specified pid does not correspond to a process, the kernel will return `-EBADPROC`. + +If the subject path does not have the `JOVE_PERM_MUTATE` permission, the kernel will return `-EPERM`. + +If the send timeout expires and the object was not sent, the kernel will retun `-ETIMEOUT`. + +If the receive timeout expires and an object was not recieved, the kernel will return `-ETIMEOUT`. + +Successful swap returns `0`. + + +#### SYSCALL_PCB_STACK + +Marks a page-aligned untyped object as either the interrupt stack or the system stack. + +Only one page is allowed per stack per process. Both stacks are required for a PCB to be placed in the READY queue. + +| Data | Stack Type | Stack Path Length | Stack Path | +|--------------|------------|------------------------|-------------------------------------------| +| Size (bytes) | 1 | sizeof(objpath_part_t) | stack_path_length * sizeof(objpath_part_t | + +If the stack type is not present in the pcb_stack_type enum, the kernel will return `-EBADARG`. + +If the subject object is not a `JOVE_OBJ_UNTYPED` object, the kernel will return `-EBADOBJ`. + +If the untyped is not the size of a page, the kernel will return `-EBADSIZE`. + +If the untyped is not aligned to a page boundary, the kernel will return `-EALIGN`. + +If the PCB already has a stack of the specified type, the kernel will return `-EFULL`. + +Successful operation returns `0`. + + ### JOVE_OBJ_INITRD_FILE | Syscall | Target Permissions | |