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 sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT); 67 } 68 69 SYSCALL_DEFINE6(mips_mmap2, unsigned long, addr, unsigned long, len, 70 unsigned long, prot, unsigned long, flags, unsigned long, fd, 71 unsigned long, pgoff) 72 { 73 if (pgoff & (~PAGE_MASK >> 12)) 74 return -EINVAL; 75 76 return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12)); 77 } 78 79 save_static_function(sys_fork); 80 save_static_function(sys_clone); 81 82 SYSCALL_DEFINE1(set_thread_area, unsigned long, addr) 83 { 84 struct thread_info *ti = task_thread_info(current); 85 86 ti->tp_value = addr; 87 if (cpu_has_userlocal) 88 write_c0_userlocal(addr); 89 90 return 0; 91 } 92 93 static inline int mips_atomic_set(unsigned long addr, unsigned long new) 94 { 95 unsigned long old, tmp; 96 struct pt_regs *regs; 97 unsigned int err; 98 99 if (unlikely(addr & 3)) 100 return -EINVAL; 101 102 if (unlikely(!access_ok(VERIFY_WRITE, (const void __user *)addr, 4))) 103 return -EINVAL; 104 105 if (cpu_has_llsc && R10000_LLSC_WAR) { 106 __asm__ __volatile__ ( 107 " .set arch=r4000 \n" 108 " li %[err], 0 \n" 109 "1: ll %[old], (%[addr]) \n" 110 " move %[tmp], %[new] \n" 111 "2: sc %[tmp], (%[addr]) \n" 112 " beqzl %[tmp], 1b \n" 113 "3: \n" 114 " .insn \n" 115 " .section .fixup,\"ax\" \n" 116 "4: li %[err], %[efault] \n" 117 " j 3b \n" 118 " .previous \n" 119 " .section __ex_table,\"a\" \n" 120 " "STR(PTR)" 1b, 4b \n" 121 " "STR(PTR)" 2b, 4b \n" 122 " .previous \n" 123 " .set mips0 \n" 124 : [old] "=&r" (old), 125 [err] "=&r" (err), 126 [tmp] "=&r" (tmp) 127 : [addr] "r" (addr), 128 [new] "r" (new), 129 [efault] "i" (-EFAULT) 130 : "memory"); 131 } else if (cpu_has_llsc) { 132 __asm__ __volatile__ ( 133 " .set "MIPS_ISA_ARCH_LEVEL" \n" 134 " li %[err], 0 \n" 135 "1: \n" 136 user_ll("%[old]", "(%[addr])") 137 " move %[tmp], %[new] \n" 138 "2: \n" 139 user_sc("%[tmp]", "(%[addr])") 140 " beqz %[tmp], 1b \n" 141 "3: \n" 142 " .insn \n" 143 " .section .fixup,\"ax\" \n" 144 "5: li %[err], %[efault] \n" 145 " j 3b \n" 146 " .previous \n" 147 " .section __ex_table,\"a\" \n" 148 " "STR(PTR)" 1b, 5b \n" 149 " "STR(PTR)" 2b, 5b \n" 150 " .previous \n" 151 " .set mips0 \n" 152 : [old] "=&r" (old), 153 [err] "=&r" (err), 154 [tmp] "=&r" (tmp) 155 : [addr] "r" (addr), 156 [new] "r" (new), 157 [efault] "i" (-EFAULT) 158 : "memory"); 159 } else { 160 do { 161 preempt_disable(); 162 ll_bit = 1; 163 ll_task = current; 164 preempt_enable(); 165 166 err = __get_user(old, (unsigned int *) addr); 167 err |= __put_user(new, (unsigned int *) addr); 168 if (err) 169 break; 170 rmb(); 171 } while (!ll_bit); 172 } 173 174 if (unlikely(err)) 175 return err; 176 177 regs = current_pt_regs(); 178 regs->regs[2] = old; 179 regs->regs[7] = 0; /* No error */ 180 181 /* 182 * Don't let your children do this ... 183 */ 184 __asm__ __volatile__( 185 " move $29, %0 \n" 186 " j syscall_exit \n" 187 : /* no outputs */ 188 : "r" (regs)); 189 190 /* unreached. Honestly. */ 191 unreachable(); 192 } 193 194 /* 195 * mips_atomic_set() normally returns directly via syscall_exit potentially 196 * clobbering static registers, so be sure to preserve them. 197 */ 198 save_static_function(sys_sysmips); 199 200 SYSCALL_DEFINE3(sysmips, long, cmd, long, arg1, long, arg2) 201 { 202 switch (cmd) { 203 case MIPS_ATOMIC_SET: 204 return mips_atomic_set(arg1, arg2); 205 206 case MIPS_FIXADE: 207 if (arg1 & ~3) 208 return -EINVAL; 209 210 if (arg1 & 1) 211 set_thread_flag(TIF_FIXADE); 212 else 213 clear_thread_flag(TIF_FIXADE); 214 if (arg1 & 2) 215 set_thread_flag(TIF_LOGADE); 216 else 217 clear_thread_flag(TIF_LOGADE); 218 219 return 0; 220 221 case FLUSH_CACHE: 222 __flush_cache_all(); 223 return 0; 224 } 225 226 return -EINVAL; 227 } 228 229 /* 230 * No implemented yet ... 231 */ 232 SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op) 233 { 234 return -ENOSYS; 235 } 236 237 /* 238 * If we ever come here the user sp is bad. Zap the process right away. 239 * Due to the bad stack signaling wouldn't work. 240 */ 241 asmlinkage void bad_stack(void) 242 { 243 do_exit(SIGSEGV); 244 } 245