/* * Copyright (c) 2016, Stefan Lankes, RWTH Aachen University * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this * software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include #include void __startcontext(void); void makecontext(ucontext_t *ucp, void (*func)(), int argc, ...) { va_list ap; if (BUILTIN_EXPECT(!ucp, 0)) return; LOG_DEBUG("sys_makecontext %p, func %p, stack 0x%zx, task %d\n", ucp, func, ucp->uc_stack.ss_sp, per_core(current_task)->id); size_t* stack = (size_t*) ((size_t)ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size); stack -= (argc > 6 ? argc - 6 : 0) + 1; uint32_t idx = (argc > 6 ? argc - 6 : 0) + 1; /* Align stack and reserve space for trampoline address. */ stack = (size_t*) ((((size_t) stack) & ~0xFULL) - 0x8); /* Setup context */ ucp->uc_mregs.rip = (size_t) func; ucp->uc_mregs.rbx = (size_t) &stack[idx]; ucp->uc_mregs.rsp = (size_t) stack; stack[0] = (size_t) &__startcontext; stack[idx] = (size_t) ucp->uc_link; // link to the next context va_start(ap, argc); for (int i = 0; i < argc; i++) { switch (i) { case 0: ucp->uc_mregs.rdi = va_arg(ap, size_t); break; case 1: ucp->uc_mregs.rsi = va_arg(ap, size_t); break; case 2: ucp->uc_mregs.rdx = va_arg(ap, size_t); break; case 3: ucp->uc_mregs.rcx = va_arg(ap, size_t); break; case 4: ucp->uc_mregs.r8 = va_arg(ap, size_t); break; case 5: ucp->uc_mregs.r9 = va_arg(ap, size_t); break; default: /* copy value on stack */ stack[i - 5] = va_arg(ap, size_t); break; } } va_end(ap); } int swapcontext(ucontext_t *oucp, const ucontext_t *ucp) { //TODO: implementation is missing LOG_WARNING("sys_swapcontext is currently not implemented: %p <=> %p\n", oucp, ucp); return -ENOSYS; }