Commit Graph

4 Commits

Author SHA1 Message Date
Justin C. Miller
cd037aca15 [kernel] Let objects inherit caps from superclasses
The main point of this change is to allow "global" capabilities defined
on the base object type. The example here is the clone capability on all
objects, which governs the ability to clone a handle.

Related changes in this commit:
- Renamed `kobject` to `object` as far as the syscall interface is
  concerned. `kobject` is the cname, but j6_cap_kobject_clone feels
  clunky.
- The above change made me realize that the "object <type>" syntax for
  specifying object references was also clunky, so now it's "ref <type>"
- Having to add `.object` on everywhere to access objects in
  interface.exposes or object.super was cumbersome, so those properties
  now return object types directly, instead of ObjectRef.
- syscall_verify.cpp.cog now generates code to check capabilities on
  handles if they're specified in the definition, even when not passing
  an object to the implementation function.
2022-01-29 15:56:33 -08:00
Justin C. Miller
f1246f84e0 [kernel] Add capabilities to handles
This change finally adds capabilities to handles. Included changes:

- j6_handle_t is now again 64 bits, with the highest 8 bits being a type
  code, and the next highest 24 bits being the capability mask, so that
  programs can check type/caps without calling the kernel.
- The definitions grammar now includes a `capabilities [ ]` section on
  objects, to list what capabilities are relevant.
- j6/caps.h is auto-generated from object capability lists
- init_libj6 again sets __handle_self and __handle_sys, this is a bit
  of a hack.
- A new syscall, j6_handle_list, will return the list of existing
  handles owned by the calling process.
- syscall_verify.cpp.cog now actually checks that the needed
  capabilities exist on handles before allowing the call.
2022-01-28 01:54:45 -08:00
Justin C. Miller
300bf9c2c5 [kernel] Stop creating user stacks in the kernel
Stop creating stacks in user space for user threads, that should be done
by the thread's creator. This change adds process and stack_top
arguments to the thread_create syscall, so that threads can be created
in other processes, and given a stack address.

Also included is a fix in add_thunk_user due to the r11/flags change.

THIS COMMIT BREAKS USERSPACE. See subsequent commits for the user side
changes related to this change.
2021-12-26 15:36:59 -08:00
Justin C. Miller
186724e751 [project] Generate syscalls from new interface DSL
This change adds a new interface DSL for specifying objects (with
methods) and interfaces (that expose objects, and optionally have their
own methods).

Significant changes:

- Add the new scripts/definitions Python module to parse the DSL
- Add the new definitions directory containing DSL definition files
- Use cog to generate syscall-related code in kernel and libj6
- Unify ordering of pointer + length pairs in interfaces
2021-08-30 01:05:32 -07:00