diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/syscall.md | 60 |
1 files changed, 56 insertions, 4 deletions
diff --git a/doc/syscall.md b/doc/syscall.md index 9304785..3bfa00b 100644 --- a/doc/syscall.md +++ b/doc/syscall.md @@ -8,9 +8,9 @@ To resolve the message object, the kernel requires an object path and a path len On x86_64, the encoding is as follows: -| | Message Path | Message Path Length | -|----------|--------------|---------------------| -| Register | rdi | rsi | +| Message Path | Message Path Length | +|--------------|---------------------| +| rdi | rsi | If the message path exceeds the width of the message path register, the kernel will return `-EBADPATH`. @@ -118,7 +118,7 @@ If the entry index exceeds `JOVE_OBJDIR_ENTRIES`, the kernel returns `-EOOB`. |-----------------------------|:-------------------------------:|:-------------------------------------------------:|:-------------------------------:| | SYSCALL_PAGEDIR_MAP_FRAME | JOVE_PERM_READ, JOVE_PERM_WRITE | JOVE_PERM_MUTATE | JOVE_PERM_READ, JOVE_PERM_WRITE | | SYSCALL_PAGEDIR_MAP_TABLE | JOVE_PERM_READ, JOVE_PERM_WRITE | JOVE_PERM_READ, JOVE_PERM_WRITE, JOVE_PERM_MUTATE | | -| SYSCALL_PAGEDIR_MAP_SHMEM | JOVE_PERM_READ, JOVE_PERM_WRITE | | JOVE_PERM_READ, JOVE_PERM_WRITE | +| SYSCALL_PAGEDIR_MAP_SHMEM | JOVE_PERM_READ, JOVE_PERM_WRITE | JOVE_PERM_READ | JOVE_PERM_WRITE | | SYSCALL_PAGEDIR_UNMAP_FRAME | JOVE_PERM_READ, JOVE_PERM_WRITE | | | | SYSCALL_PAGEDIR_UNMAP_TABLE | JOVE_PERM_READ, JOVE_PERM_WRITE | | | | SYSCALL_PAGEDIR_UNMAP_SHMEM | JOVE_PERM_READ, JOVE_PERM_WRITE | | | @@ -262,3 +262,55 @@ If the virtual address does not have a page frame associated with it, the kernel If the page frame pointed to by virtual address does not correspond to a shared memory frame, the kernel will return `-EBADOBJ`. Successful unmapping returns `0`. + +### JOVE_OBJ_INITRD_FILE + +| Syscall | Target Permissions | +|--------------------------|--------------------| +| SYSCALL_INITRD_FILE_NAME | JOVE_PERM_READ | +| SYSCALL_INITRD_FILE_SIZE | JOVE_PERM_READ | +| SYSCALL_INITRD_FILE_READ | JOVE_PERM_READ | + +#### SYSCALL_INITRD_FILE_NAME + +Populates the message with the name of the target file. + +Names start with a size_t length specifier, which is followed by a NULL-terminated c-string. + +| Data | Name Length | Name | Null Terminator | +|--------------|----------------|-------------|-----------------| +| Size (bytes) | sizeof(size_t) | Name Length | 1 | + + +If the message is too small for the file name, the kernel will return `-ETOOSMALL`. + +#### SYSCALL_INITRD_FILE_SIZE + +Returns the size of the target file in bytes. + +#### SYSCALL_INITRD_FILE_READ + +Populates the message with the bytes read from the target file. + +##### Payload + +| Data | Starting index | Read size | +|--------------|----------------|----------------| +| Size (bytes) | sizeof(size_t) | sizeof(size_t) | + +##### Return + +| Data | Data | +|--------------|-----------| +| Size (bytes) | Read size | + + +If the message is too small for the syscall payload, the kernel will return `-ETOOSMALL`. + +If the starting index exceeds the file length, the kernel will return `-EOOB`. + +If the read size + starting index > file size, the kernel will return `-EOOB`. + +If the message is too small for the read bytes, the kernel will return `-ETOOBIG`. + +Successful reading returns `0`. |