Subversion Repositories c0or1k

/*

 * Thread creation userspace helpers

 *

 * Copyright (C) 2009 B Labs Ltd.

 */

#include <thread.h>

#include <l4/api/errno.h>

char stack[THREADS_TOTAL][STACK_SIZE] ALIGN(8);

char *__stack_ptr = &stack[1][0];

char utcb[THREADS_TOTAL][UTCB_SIZE] ALIGN(8);

char *__utcb_ptr = &utcb[1][0];

extern void local_setup_new_thread(void);

int thread_create(int (*func)(void *), void *args, unsigned int flags,

                  struct task_ids *new_ids)

{

        struct task_ids ids;

        struct exregs_data exregs;

        int err;

        l4_getid(&ids);

        /* Shared space only */

        if (!(TC_SHARE_SPACE & flags)) {

                printf("%s: This function allows only "

                       "shared space thread creation.\n",

                       __FUNCTION__);

                return -EINVAL;

        }

        /* Create thread */

        if ((err = l4_thread_control(THREAD_CREATE | flags, &ids)) < 0)

                return err;

        /* Check if more stack/utcb available */

        if ((unsigned long)__utcb_ptr ==

            (unsigned long)&utcb[THREADS_TOTAL][0])

                return -ENOMEM;

        if ((unsigned long)__stack_ptr ==

            (unsigned long)&stack[THREADS_TOTAL][0])

                return -ENOMEM;

        /* First word of new stack is arg */

        *(((unsigned int *)__stack_ptr) -1) = (unsigned int)args;

        /* Second word of new stack is function address */

        *(((unsigned int *)__stack_ptr) -2) = (unsigned int)func;

        /* Setup new thread pc, sp, utcb */

        memset(&exregs, 0, sizeof(exregs));

        exregs_set_stack(&exregs, (unsigned long)__stack_ptr);

        exregs_set_utcb(&exregs, (unsigned long)__utcb_ptr);

        exregs_set_pc(&exregs, (unsigned long)local_setup_new_thread);

        if ((err = l4_exchange_registers(&exregs, ids.tid)) < 0)

                return err;

        /* Update utcb, stack pointers */

        __stack_ptr += STACK_SIZE;

        __utcb_ptr += UTCB_SIZE;

        /* Start the new thread */

        if ((err = l4_thread_control(THREAD_RUN, &ids)) < 0)

                return err;

        memcpy(new_ids, &ids, sizeof(ids));

        return 0;

}