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/sysmips.h> 41 #include <asm/switch_to.h> 42 43 /* 44 * For historic reasons the pipe(2) syscall on MIPS has an unusual calling 45 * convention. It returns results in registers $v0 / $v1 which means there 46 * is no need for it to do verify the validity of a userspace pointer 47 * argument. Historically that used to be expensive in Linux. These days 48 * the performance advantage is negligible. 49 */ 50 asmlinkage int sysm_pipe(void) 51 { 52 int fd[2]; 53 int error = do_pipe_flags(fd, 0); 54 if (error) 55 return error; 56 current_pt_regs()->regs[3] = fd[1]; 57 return fd[0]; 58 } 59 60 SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len, 61 unsigned long, prot, unsigned long, flags, unsigned long, 62 fd, off_t, offset) 63 { 64 if (offset & ~PAGE_MASK) 65 return -EINVAL; 66 return ksys_mmap_pgoff(addr, len, prot, flags, fd, 67 offset >> PAGE_SHIFT); 68 } 69 70 SYSCALL_DEFINE6(mips_mmap2, unsigned long, addr, unsigned long, len, 71 unsigned long, prot, unsigned long, flags, unsigned long, fd, 72 unsigned long, pgoff) 73 { 74 if (pgoff & (~PAGE_MASK >> 12)) 75 return -EINVAL; 76 77 return ksys_mmap_pgoff(addr, len, prot, flags, fd, 78 pgoff >> (PAGE_SHIFT - 12)); 79 } 80 81 save_static_function(sys_fork); 82 save_static_function(sys_clone); 83 save_static_function(sys_clone3); 84 85 SYSCALL_DEFINE1(set_thread_area, unsigned long, addr) 86 { 87 struct thread_info *ti = task_thread_info(current); 88 89 ti->tp_value = addr; 90 if (cpu_has_userlocal) 91 write_c0_userlocal(addr); 92 93 return 0; 94 } 95 96 static inline int mips_atomic_set(unsigned long addr, unsigned long new) 97 { 98 unsigned long old, tmp; 99 struct pt_regs *regs; 100 unsigned int err; 101 102 if (unlikely(addr & 3)) 103 return -EINVAL; 104 105 if (unlikely(!access_ok((const void __user *)addr, 4))) 106 return -EINVAL; 107 108 if (cpu_has_llsc && R10000_LLSC_WAR) { 109 __asm__ __volatile__ ( 110 " .set push \n" 111 " .set arch=r4000 \n" 112 " li %[err], 0 \n" 113 "1: ll %[old], (%[addr]) \n" 114 " move %[tmp], %[new] \n" 115 "2: sc %[tmp], (%[addr]) \n" 116 " beqzl %[tmp], 1b \n" 117 "3: \n" 118 " .insn \n" 119 " .section .fixup,\"ax\" \n" 120 "4: li %[err], %[efault] \n" 121 " j 3b \n" 122 " .previous \n" 123 " .section __ex_table,\"a\" \n" 124 " "STR(PTR)" 1b, 4b \n" 125 " "STR(PTR)" 2b, 4b \n" 126 " .previous \n" 127 " .set pop \n" 128 : [old] "=&r" (old), 129 [err] "=&r" (err), 130 [tmp] "=&r" (tmp) 131 : [addr] "r" (addr), 132 [new] "r" (new), 133 [efault] "i" (-EFAULT) 134 : "memory"); 135 } else if (cpu_has_llsc) { 136 loongson_llsc_mb(); 137 __asm__ __volatile__ ( 138 " .set push \n" 139 " .set "MIPS_ISA_ARCH_LEVEL" \n" 140 " li %[err], 0 \n" 141 "1: \n" 142 user_ll("%[old]", "(%[addr])") 143 " move %[tmp], %[new] \n" 144 "2: \n" 145 user_sc("%[tmp]", "(%[addr])") 146 " beqz %[tmp], 1b \n" 147 "3: \n" 148 " .insn \n" 149 " .section .fixup,\"ax\" \n" 150 "5: li %[err], %[efault] \n" 151 " j 3b \n" 152 " .previous \n" 153 " .section __ex_table,\"a\" \n" 154 " "STR(PTR)" 1b, 5b \n" 155 " "STR(PTR)" 2b, 5b \n" 156 " .previous \n" 157 " .set pop \n" 158 : [old] "=&r" (old), 159 [err] "=&r" (err), 160 [tmp] "=&r" (tmp) 161 : [addr] "r" (addr), 162 [new] "r" (new), 163 [efault] "i" (-EFAULT) 164 : "memory"); 165 } else { 166 do { 167 preempt_disable(); 168 ll_bit = 1; 169 ll_task = current; 170 preempt_enable(); 171 172 err = __get_user(old, (unsigned int *) addr); 173 err |= __put_user(new, (unsigned int *) addr); 174 if (err) 175 break; 176 rmb(); 177 } while (!ll_bit); 178 } 179 180 if (unlikely(err)) 181 return err; 182 183 regs = current_pt_regs(); 184 regs->regs[2] = old; 185 regs->regs[7] = 0; /* No error */ 186 187 /* 188 * Don't let your children do this ... 189 */ 190 __asm__ __volatile__( 191 " move $29, %0 \n" 192 " j syscall_exit \n" 193 : /* no outputs */ 194 : "r" (regs)); 195 196 /* unreached. Honestly. */ 197 unreachable(); 198 } 199 200 /* 201 * mips_atomic_set() normally returns directly via syscall_exit potentially 202 * clobbering static registers, so be sure to preserve them. 203 */ 204 save_static_function(sys_sysmips); 205 206 SYSCALL_DEFINE3(sysmips, long, cmd, long, arg1, long, arg2) 207 { 208 switch (cmd) { 209 case MIPS_ATOMIC_SET: 210 return mips_atomic_set(arg1, arg2); 211 212 case MIPS_FIXADE: 213 if (arg1 & ~3) 214 return -EINVAL; 215 216 if (arg1 & 1) 217 set_thread_flag(TIF_FIXADE); 218 else 219 clear_thread_flag(TIF_FIXADE); 220 if (arg1 & 2) 221 set_thread_flag(TIF_LOGADE); 222 else 223 clear_thread_flag(TIF_LOGADE); 224 225 return 0; 226 227 case FLUSH_CACHE: 228 __flush_cache_all(); 229 return 0; 230 } 231 232 return -EINVAL; 233 } 234 235 /* 236 * No implemented yet ... 237 */ 238 SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op) 239 { 240 return -ENOSYS; 241 } 242 243 /* 244 * If we ever come here the user sp is bad. Zap the process right away. 245 * Due to the bad stack signaling wouldn't work. 246 */ 247 asmlinkage void bad_stack(void) 248 { 249 do_exit(SIGSEGV); 250 } 251