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 */ 51 asmlinkage 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 61 SYSCALL_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 71 SYSCALL_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 82 save_static_function(sys_fork); 83 save_static_function(sys_clone); 84 save_static_function(sys_clone3); 85 86 SYSCALL_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 97 static 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)" 1b, 4b \n" 126 " "STR(PTR)" 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)" 1b, 5b \n" 156 " "STR(PTR)" 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 */ 205 save_static_function(sys_sysmips); 206 207 SYSCALL_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 */ 239 SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op) 240 { 241 return -ENOSYS; 242 } 243 244 /* 245 * If we ever come here the user sp is bad. Zap the process right away. 246 * Due to the bad stack signaling wouldn't work. 247 */ 248 asmlinkage void bad_stack(void) 249 { 250 do_exit(SIGSEGV); 251 } 252