1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Author: Hanlu Li <lihanlu@loongson.cn> 4 * Huacai Chen <chenhuacai@loongson.cn> 5 * 6 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 7 */ 8 #include <linux/capability.h> 9 #include <linux/entry-common.h> 10 #include <linux/errno.h> 11 #include <linux/linkage.h> 12 #include <linux/nospec.h> 13 #include <linux/objtool.h> 14 #include <linux/randomize_kstack.h> 15 #include <linux/syscalls.h> 16 #include <linux/unistd.h> 17 18 #include <asm/asm.h> 19 #include <asm/exception.h> 20 #include <asm/loongarch.h> 21 #include <asm/signal.h> 22 #include <asm/switch_to.h> 23 #include <asm-generic/syscalls.h> 24 25 #undef __SYSCALL 26 #define __SYSCALL(nr, call) [nr] = (call), 27 #define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native) 28 29 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len, unsigned long, 30 prot, unsigned long, flags, unsigned long, fd, unsigned long, offset) 31 { 32 if (offset & ~PAGE_MASK) 33 return -EINVAL; 34 35 return ksys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT); 36 } 37 38 SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len, unsigned long, 39 prot, unsigned long, flags, unsigned long, fd, unsigned long, offset) 40 { 41 if (offset & (~PAGE_MASK >> 12)) 42 return -EINVAL; 43 44 return ksys_mmap_pgoff(addr, len, prot, flags, fd, offset >> (PAGE_SHIFT - 12)); 45 } 46 47 void *sys_call_table[__NR_syscalls] = { 48 [0 ... __NR_syscalls - 1] = sys_ni_syscall, 49 #ifdef CONFIG_32BIT 50 #include <asm/syscall_table_32.h> 51 #else 52 #include <asm/syscall_table_64.h> 53 #endif 54 }; 55 56 typedef long (*sys_call_fn)(unsigned long, unsigned long, 57 unsigned long, unsigned long, unsigned long, unsigned long); 58 59 void noinstr __no_stack_protector do_syscall(struct pt_regs *regs) 60 { 61 unsigned long nr; 62 sys_call_fn syscall_fn; 63 64 nr = regs->regs[11]; 65 /* Set for syscall restarting */ 66 if (nr < NR_syscalls) 67 regs->regs[0] = nr + 1; 68 69 regs->csr_era += 4; 70 regs->orig_a0 = regs->regs[4]; 71 regs->regs[4] = -ENOSYS; 72 73 nr = syscall_enter_from_user_mode(regs, nr); 74 75 add_random_kstack_offset(); 76 77 if (nr < NR_syscalls) { 78 syscall_fn = sys_call_table[array_index_nospec(nr, NR_syscalls)]; 79 regs->regs[4] = syscall_fn(regs->orig_a0, regs->regs[5], regs->regs[6], 80 regs->regs[7], regs->regs[8], regs->regs[9]); 81 } 82 83 syscall_exit_to_user_mode(regs); 84 } 85