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
SYSCALL_DEFINE6(mmap,unsigned long,addr,unsigned long,len,unsigned long,prot,unsigned long,flags,unsigned long,fd,unsigned long,offset)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
SYSCALL_DEFINE6(mmap2,unsigned long,addr,unsigned long,len,unsigned long,prot,unsigned long,flags,unsigned long,fd,unsigned long,offset)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
do_syscall(struct pt_regs * regs)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