syscall.c (5652B)
1/* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 1995, 1996, 1997, 2000, 2001, 05 by Ralf Baechle 7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc. 8 * Copyright (C) 2001 MIPS Technologies, Inc. 9 */ 10#include <linux/capability.h> 11#include <linux/errno.h> 12#include <linux/linkage.h> 13#include <linux/fs.h> 14#include <linux/smp.h> 15#include <linux/ptrace.h> 16#include <linux/string.h> 17#include <linux/syscalls.h> 18#include <linux/file.h> 19#include <linux/utsname.h> 20#include <linux/unistd.h> 21#include <linux/sem.h> 22#include <linux/msg.h> 23#include <linux/shm.h> 24#include <linux/compiler.h> 25#include <linux/ipc.h> 26#include <linux/uaccess.h> 27#include <linux/slab.h> 28#include <linux/elf.h> 29#include <linux/sched/task_stack.h> 30 31#include <asm/asm.h> 32#include <asm/asm-eva.h> 33#include <asm/branch.h> 34#include <asm/cachectl.h> 35#include <asm/cacheflush.h> 36#include <asm/asm-offsets.h> 37#include <asm/signal.h> 38#include <asm/sim.h> 39#include <asm/shmparam.h> 40#include <asm/sync.h> 41#include <asm/sysmips.h> 42#include <asm/switch_to.h> 43 44/* 45 * For historic reasons the pipe(2) syscall on MIPS has an unusual calling 46 * convention. It returns results in registers $v0 / $v1 which means there 47 * is no need for it to do verify the validity of a userspace pointer 48 * argument. Historically that used to be expensive in Linux. These days 49 * the performance advantage is negligible. 50 */ 51asmlinkage int sysm_pipe(void) 52{ 53 int fd[2]; 54 int error = do_pipe_flags(fd, 0); 55 if (error) 56 return error; 57 current_pt_regs()->regs[3] = fd[1]; 58 return fd[0]; 59} 60 61SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len, 62 unsigned long, prot, unsigned long, flags, unsigned long, 63 fd, off_t, offset) 64{ 65 if (offset & ~PAGE_MASK) 66 return -EINVAL; 67 return ksys_mmap_pgoff(addr, len, prot, flags, fd, 68 offset >> PAGE_SHIFT); 69} 70 71SYSCALL_DEFINE6(mips_mmap2, unsigned long, addr, unsigned long, len, 72 unsigned long, prot, unsigned long, flags, unsigned long, fd, 73 unsigned long, pgoff) 74{ 75 if (pgoff & (~PAGE_MASK >> 12)) 76 return -EINVAL; 77 78 return ksys_mmap_pgoff(addr, len, prot, flags, fd, 79 pgoff >> (PAGE_SHIFT - 12)); 80} 81 82save_static_function(sys_fork); 83save_static_function(sys_clone); 84save_static_function(sys_clone3); 85 86SYSCALL_DEFINE1(set_thread_area, unsigned long, addr) 87{ 88 struct thread_info *ti = task_thread_info(current); 89 90 ti->tp_value = addr; 91 if (cpu_has_userlocal) 92 write_c0_userlocal(addr); 93 94 return 0; 95} 96 97static inline int mips_atomic_set(unsigned long addr, unsigned long new) 98{ 99 unsigned long old, tmp; 100 struct pt_regs *regs; 101 unsigned int err; 102 103 if (unlikely(addr & 3)) 104 return -EINVAL; 105 106 if (unlikely(!access_ok((const void __user *)addr, 4))) 107 return -EINVAL; 108 109 if (cpu_has_llsc && IS_ENABLED(CONFIG_WAR_R10000_LLSC)) { 110 __asm__ __volatile__ ( 111 " .set push \n" 112 " .set arch=r4000 \n" 113 " li %[err], 0 \n" 114 "1: ll %[old], (%[addr]) \n" 115 " move %[tmp], %[new] \n" 116 "2: sc %[tmp], (%[addr]) \n" 117 " beqzl %[tmp], 1b \n" 118 "3: \n" 119 " .insn \n" 120 " .section .fixup,\"ax\" \n" 121 "4: li %[err], %[efault] \n" 122 " j 3b \n" 123 " .previous \n" 124 " .section __ex_table,\"a\" \n" 125 " "STR(PTR_WD)" 1b, 4b \n" 126 " "STR(PTR_WD)" 2b, 4b \n" 127 " .previous \n" 128 " .set pop \n" 129 : [old] "=&r" (old), 130 [err] "=&r" (err), 131 [tmp] "=&r" (tmp) 132 : [addr] "r" (addr), 133 [new] "r" (new), 134 [efault] "i" (-EFAULT) 135 : "memory"); 136 } else if (cpu_has_llsc) { 137 __asm__ __volatile__ ( 138 " .set push \n" 139 " .set "MIPS_ISA_ARCH_LEVEL" \n" 140 " li %[err], 0 \n" 141 "1: \n" 142 " " __SYNC(full, loongson3_war) " \n" 143 user_ll("%[old]", "(%[addr])") 144 " move %[tmp], %[new] \n" 145 "2: \n" 146 user_sc("%[tmp]", "(%[addr])") 147 " beqz %[tmp], 1b \n" 148 "3: \n" 149 " .insn \n" 150 " .section .fixup,\"ax\" \n" 151 "5: li %[err], %[efault] \n" 152 " j 3b \n" 153 " .previous \n" 154 " .section __ex_table,\"a\" \n" 155 " "STR(PTR_WD)" 1b, 5b \n" 156 " "STR(PTR_WD)" 2b, 5b \n" 157 " .previous \n" 158 " .set pop \n" 159 : [old] "=&r" (old), 160 [err] "=&r" (err), 161 [tmp] "=&r" (tmp) 162 : [addr] "r" (addr), 163 [new] "r" (new), 164 [efault] "i" (-EFAULT) 165 : "memory"); 166 } else { 167 do { 168 preempt_disable(); 169 ll_bit = 1; 170 ll_task = current; 171 preempt_enable(); 172 173 err = __get_user(old, (unsigned int *) addr); 174 err |= __put_user(new, (unsigned int *) addr); 175 if (err) 176 break; 177 rmb(); 178 } while (!ll_bit); 179 } 180 181 if (unlikely(err)) 182 return err; 183 184 regs = current_pt_regs(); 185 regs->regs[2] = old; 186 regs->regs[7] = 0; /* No error */ 187 188 /* 189 * Don't let your children do this ... 190 */ 191 __asm__ __volatile__( 192 " move $29, %0 \n" 193 " j syscall_exit \n" 194 : /* no outputs */ 195 : "r" (regs)); 196 197 /* unreached. Honestly. */ 198 unreachable(); 199} 200 201/* 202 * mips_atomic_set() normally returns directly via syscall_exit potentially 203 * clobbering static registers, so be sure to preserve them. 204 */ 205save_static_function(sys_sysmips); 206 207SYSCALL_DEFINE3(sysmips, long, cmd, long, arg1, long, arg2) 208{ 209 switch (cmd) { 210 case MIPS_ATOMIC_SET: 211 return mips_atomic_set(arg1, arg2); 212 213 case MIPS_FIXADE: 214 if (arg1 & ~3) 215 return -EINVAL; 216 217 if (arg1 & 1) 218 set_thread_flag(TIF_FIXADE); 219 else 220 clear_thread_flag(TIF_FIXADE); 221 if (arg1 & 2) 222 set_thread_flag(TIF_LOGADE); 223 else 224 clear_thread_flag(TIF_LOGADE); 225 226 return 0; 227 228 case FLUSH_CACHE: 229 __flush_cache_all(); 230 return 0; 231 } 232 233 return -EINVAL; 234} 235 236/* 237 * No implemented yet ... 238 */ 239SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op) 240{ 241 return -ENOSYS; 242}