source: mainline/kernel/generic/include/userspace.h@ d3109ff

Last change on this file since d3109ff was 3fcea34, checked in by Jiří Zárevúcky <zarevucky.jiri@…>, 9 months ago

Simplify the SYS_THREAD_CREATE syscall interface

Removed the beefy uarg structure. Instead, the syscall gets two
parameters: %pc (program counter) and %sp (stack pointer). It starts
a thread with those values in corresponding registers, with no other
fuss whatsoever.

libc initializes threads by storing any other needed arguments on
the stack and retrieving them in thread_entry. Importantly, this
includes the address of the thread_main function which is now
called indirectly to fix dynamic linking issues on some archs.

There's a bit of weirdness on SPARC and IA-64, because of their
stacked register handling. The current solution is that we require
some space *above* the stack pointer to be available for those
architectures. I think for SPARC, it can be made more normal.

For the remaining ones, we can (probably) just set the initial
%sp to the top edge of the stack. There's some lingering offsets
on some archs just because I didn't want to accidentally break
anything. The initial thread bringup should be functionally
unchanged from the previous state, and no binaries are currently
multithreaded except thread1 test, so there should be minimal
risk of breakage. Naturally, I tested all available emulator
builds, save for msim.
  • Property mode set to 100644
File size: 1.8 KB
RevLine 
[f761f1eb]1/*
[df4ed85]2 * Copyright (c) 2005 Jakub Jermar
[f761f1eb]3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
[174156fd]29/** @addtogroup kernel_generic
[b45c443]30 * @{
31 */
32/** @file
33 */
34
[06e1e95]35#ifndef KERN_USERSPACE_H_
36#define KERN_USERSPACE_H_
[f761f1eb]37
[9f52563]38#include <proc/thread.h>
[d99c1d2]39#include <typedefs.h>
[de6b301]40
[3fcea34]41extern uintptr_t arch_get_initial_sp(uintptr_t stack_base, uintptr_t stack_size);
42
[9f52563]43/** Switch to user-space (CPU user priviledge level) */
[3fcea34]44extern void userspace(sysarg_t pc, sysarg_t sp) __attribute__((noreturn));
[f761f1eb]45
46#endif
[b45c443]47
[42d3be3]48/** @}
[b45c443]49 */
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