1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 /* 3 * Copyright (C) 2018 David Abdurachmanov <david.abdurachmanov@gmail.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program. If not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #ifdef __LP64__ 19 #define __ARCH_WANT_NEW_STAT 20 #endif /* __LP64__ */ 21 22 #include <asm-generic/unistd.h> 23 24 /* 25 * Allows the instruction cache to be flushed from userspace. Despite RISC-V 26 * having a direct 'fence.i' instruction available to userspace (which we 27 * can't trap!), that's not actually viable when running on Linux because the 28 * kernel might schedule a process on another hart. There is no way for 29 * userspace to handle this without invoking the kernel (as it doesn't know the 30 * thread->hart mappings), so we've defined a RISC-V specific system call to 31 * flush the instruction cache. 32 * 33 * __NR_riscv_flush_icache is defined to flush the instruction cache over an 34 * address range, with the flush applying to either all threads or just the 35 * caller. We don't currently do anything with the address range, that's just 36 * in there for forwards compatibility. 37 */ 38 #ifndef __NR_riscv_flush_icache 39 #define __NR_riscv_flush_icache (__NR_arch_specific_syscall + 15) 40 #endif 41 __SYSCALL(__NR_riscv_flush_icache, sys_riscv_flush_icache) 42