1 // SPDX-License-Identifier: GPL-2.0 2 /* linux/arch/sparc/kernel/sys_sparc.c 3 * 4 * This file contains various random system calls that 5 * have a non-standard calling sequence on the Linux/sparc 6 * platform. 7 */ 8 9 #include <linux/errno.h> 10 #include <linux/types.h> 11 #include <linux/sched/signal.h> 12 #include <linux/sched/mm.h> 13 #include <linux/sched/debug.h> 14 #include <linux/mm.h> 15 #include <linux/fs.h> 16 #include <linux/file.h> 17 #include <linux/sem.h> 18 #include <linux/msg.h> 19 #include <linux/shm.h> 20 #include <linux/stat.h> 21 #include <linux/syscalls.h> 22 #include <linux/mman.h> 23 #include <linux/utsname.h> 24 #include <linux/smp.h> 25 #include <linux/ipc.h> 26 #include <linux/hugetlb.h> 27 28 #include <linux/uaccess.h> 29 #include <asm/unistd.h> 30 31 #include "systbls.h" 32 33 /* #define DEBUG_UNIMP_SYSCALL */ 34 35 /* XXX Make this per-binary type, this way we can detect the type of 36 * XXX a binary. Every Sparc executable calls this very early on. 37 */ 38 SYSCALL_DEFINE0(getpagesize) 39 { 40 return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */ 41 } 42 43 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) 44 { 45 struct vm_unmapped_area_info info = {}; 46 bool file_hugepage = false; 47 48 if (filp && is_file_hugepages(filp)) 49 file_hugepage = true; 50 51 if (flags & MAP_FIXED) { 52 /* We do not accept a shared mapping if it would violate 53 * cache aliasing constraints. 54 */ 55 if (!file_hugepage && (flags & MAP_SHARED) && 56 ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))) 57 return -EINVAL; 58 return addr; 59 } 60 61 /* See asm-sparc/uaccess.h */ 62 if (len > TASK_SIZE - PAGE_SIZE) 63 return -ENOMEM; 64 if (!addr) 65 addr = TASK_UNMAPPED_BASE; 66 67 info.length = len; 68 info.low_limit = addr; 69 info.high_limit = TASK_SIZE; 70 if (!file_hugepage) { 71 info.align_mask = (flags & MAP_SHARED) ? 72 (PAGE_MASK & (SHMLBA - 1)) : 0; 73 info.align_offset = pgoff << PAGE_SHIFT; 74 } else { 75 info.align_mask = huge_page_mask_align(filp); 76 } 77 return vm_unmapped_area(&info); 78 } 79 80 /* 81 * sys_pipe() is the normal C calling standard for creating 82 * a pipe. It's not the way unix traditionally does this, though. 83 */ 84 SYSCALL_DEFINE0(sparc_pipe) 85 { 86 int fd[2]; 87 int error; 88 89 error = do_pipe_flags(fd, 0); 90 if (error) 91 goto out; 92 current_pt_regs()->u_regs[UREG_I1] = fd[1]; 93 error = fd[0]; 94 out: 95 return error; 96 } 97 98 int sparc_mmap_check(unsigned long addr, unsigned long len) 99 { 100 /* See asm-sparc/uaccess.h */ 101 if (len > TASK_SIZE - PAGE_SIZE || addr + len > TASK_SIZE - PAGE_SIZE) 102 return -EINVAL; 103 104 return 0; 105 } 106 107 /* Linux version of mmap */ 108 109 SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len, 110 unsigned long, prot, unsigned long, flags, unsigned long, fd, 111 unsigned long, pgoff) 112 { 113 /* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE 114 we have. */ 115 return ksys_mmap_pgoff(addr, len, prot, flags, fd, 116 pgoff >> (PAGE_SHIFT - 12)); 117 } 118 119 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len, 120 unsigned long, prot, unsigned long, flags, unsigned long, fd, 121 unsigned long, off) 122 { 123 /* no alignment check? */ 124 return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT); 125 } 126 127 SYSCALL_DEFINE5(sparc_remap_file_pages, unsigned long, start, unsigned long, size, 128 unsigned long, prot, unsigned long, pgoff, 129 unsigned long, flags) 130 { 131 /* This works on an existing mmap so we don't need to validate 132 * the range as that was done at the original mmap call. 133 */ 134 return sys_remap_file_pages(start, size, prot, 135 (pgoff >> (PAGE_SHIFT - 12)), flags); 136 } 137 138 SYSCALL_DEFINE0(nis_syscall) 139 { 140 static int count = 0; 141 struct pt_regs *regs = current_pt_regs(); 142 143 if (count++ > 5) 144 return -ENOSYS; 145 printk ("%s[%d]: Unimplemented SPARC system call %d\n", 146 current->comm, task_pid_nr(current), (int)regs->u_regs[1]); 147 #ifdef DEBUG_UNIMP_SYSCALL 148 show_regs (regs); 149 #endif 150 return -ENOSYS; 151 } 152 153 /* #define DEBUG_SPARC_BREAKPOINT */ 154 155 asmlinkage void 156 sparc_breakpoint (struct pt_regs *regs) 157 { 158 159 #ifdef DEBUG_SPARC_BREAKPOINT 160 printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc); 161 #endif 162 force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc); 163 164 #ifdef DEBUG_SPARC_BREAKPOINT 165 printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc); 166 #endif 167 } 168 169 SYSCALL_DEFINE3(sparc_sigaction, int, sig, 170 struct old_sigaction __user *,act, 171 struct old_sigaction __user *,oact) 172 { 173 WARN_ON_ONCE(sig >= 0); 174 return sys_sigaction(-sig, act, oact); 175 } 176 177 SYSCALL_DEFINE5(rt_sigaction, int, sig, 178 const struct sigaction __user *, act, 179 struct sigaction __user *, oact, 180 void __user *, restorer, 181 size_t, sigsetsize) 182 { 183 struct k_sigaction new_ka, old_ka; 184 int ret; 185 186 /* XXX: Don't preclude handling different sized sigset_t's. */ 187 if (sigsetsize != sizeof(sigset_t)) 188 return -EINVAL; 189 190 if (act) { 191 new_ka.ka_restorer = restorer; 192 if (copy_from_user(&new_ka.sa, act, sizeof(*act))) 193 return -EFAULT; 194 } 195 196 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); 197 198 if (!ret && oact) { 199 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact))) 200 return -EFAULT; 201 } 202 203 return ret; 204 } 205 206 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len) 207 { 208 int nlen, err; 209 char tmp[__NEW_UTS_LEN + 1]; 210 211 if (len < 0) 212 return -EINVAL; 213 214 down_read(&uts_sem); 215 216 nlen = strlen(utsname()->domainname) + 1; 217 err = -EINVAL; 218 if (nlen > len) 219 goto out_unlock; 220 memcpy(tmp, utsname()->domainname, nlen); 221 222 up_read(&uts_sem); 223 224 if (copy_to_user(name, tmp, nlen)) 225 return -EFAULT; 226 return 0; 227 228 out_unlock: 229 up_read(&uts_sem); 230 return err; 231 } 232