- we don't need a general memset call -- just a zero page call
- use native rust semantics to embody the call. some alignment checking is
done on the arguments on the way in and out that seem worth it
- the unrolled loop doesn't pay off because we're at the limit of
write bandwidth on the CPU at this point. we would need write-back
caches to gain more performance through unrolling.
Fix a segfault that occurred when using ReplyAndReceiveNext on hosted
mode. This now properly passes memory messages back to the client.
Signed-off-by: Sean Cross <sean@xobs.io>
- strip out gdb-stub. Per xobs, the feature never worked, and it
depends upon a branch of a git repo which is not allowed by crates.io
Since the feature hasn't been developed, and crates.io will not
allow even an optional feature that points to a git repo, the feature
was stripped out.
- rename "kernel" to "xous-kernel", so that we can live in a crates.io
package namespace that is specific to Xous.
still have to figure out the riscv package issue.
Instead of passing a constructed mutable ref from the pagetable entry,
pass a raw pointer and use `read_volatile()` / `write_volatile(x)` on
this pointer.
This should remove a little bit of UB from the kernel.
Signed-off-by: Sean Cross <sean@xobs.io>
Previously, the kernel would dutifully try to map memory that was in the
kernel space. It did this by investigating the kernel memory offset,
which immediately causes a double-fault.
Check to make sure a userspace process is not trying to map kernel
memory before checking the valid page.
Signed-off-by: Sean Cross <sean@xobs.io>
Hosted mode spawns processes very differently, and this difference was
not reflected after changes were made to native mode.
Signed-off-by: Sean Cross <sean@xobs.io>
Unmap the pages from the child process after we're done setting them up.
This ensures they're not still aliased by our process, despite being
marked as "owned" by the other process.
Signed-off-by: Sean Cross <sean@xobs.io>
Implement a functioning CreateProcess syscall on riscv. This call
creates a server in the child process, and connects the server to the
parent. The parent can communicate with the child process using this
server.
The Server ID is passed as four `u32` values to the entrypoint function.
This can be reassembled into something that can then be passed to the
`ReceiveMessage` syscall.
Signed-off-by: Sean Cross <sean@xobs.io>
We now us `ProcessStartup` as the return type. This builds in tset
mode, hosted mode, and RISC-V mode.
Process Startup is still not implemented for RISC-V mode.
Signed-off-by: Sean Cross <sean@xobs.io>
If a process fails for some reason (e.g. by performing a fault) and
there is no exception handler, either terminate the process or (if
gdbserver is enabled) have it suspend the process.
Signed-off-by: Sean Cross <sean@xobs.io>
This fixes the exception handler so that it can support user-defined
exceptions. Additionally, kernel mode errors are called out now.
Signed-off-by: Sean Cross <sean@xobs.io>
When the program counter is NULL, we can still get exceptions. This
happens when we jump to an invalid address, for example.
Signed-off-by: Sean Cross <sean@xobs.io>
This fixes the MemoryRange refactor where `.addr` and `.size` are now
private fields.
Previously it had only been tested on baremetal mode.
Signed-off-by: Sean Cross <sean@xobs.io>
Ensure pages of memory can be written to when we write to them. This
lets us patch program code to, for example, insert breakpoints.
Signed-off-by: Sean Cross <sean@xobs.io>
