arch/sparc/kernel/sys_sparc_32.c

   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
  27 #include <linux/uaccess.h>
  28 #include <asm/unistd.h>
  29
  30 #include "systbls.h"
  31
  32 /* #define DEBUG_UNIMP_SYSCALL */
  33
  34 /* XXX Make this per-binary type, this way we can detect the type of
  35  * XXX a binary.  Every Sparc executable calls this very early on.
  36  */
  37 asmlinkage unsigned long sys_getpagesize(void)
  38 {
  39         return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */
  40 }
  41
  42 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
  43 {
  44         struct vm_unmapped_area_info info;
  45
  46         if (flags & MAP_FIXED) {
  47                 /* We do not accept a shared mapping if it would violate
  48                  * cache aliasing constraints.
  49                  */
  50                 if ((flags & MAP_SHARED) &&
  51                     ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
  52                         return -EINVAL;
  53                 return addr;
  54         }
  55
  56         /* See asm-sparc/uaccess.h */
  57         if (len > TASK_SIZE - PAGE_SIZE)
  58                 return -ENOMEM;
  59         if (!addr)
  60                 addr = TASK_UNMAPPED_BASE;
  61
  62         info.flags = 0;
  63         info.length = len;
  64         info.low_limit = addr;
  65         info.high_limit = TASK_SIZE;
  66         info.align_mask = (flags & MAP_SHARED) ?
  67                 (PAGE_MASK & (SHMLBA - 1)) : 0;
  68         info.align_offset = pgoff << PAGE_SHIFT;
  69         return vm_unmapped_area(&info);
  70 }
  71
  72 /*
  73  * sys_pipe() is the normal C calling standard for creating
  74  * a pipe. It's not the way unix traditionally does this, though.
  75  */
  76 asmlinkage long sparc_pipe(struct pt_regs *regs)
  77 {
  78         int fd[2];
  79         int error;
  80
  81         error = do_pipe_flags(fd, 0);
  82         if (error)
  83                 goto out;
  84         regs->u_regs[UREG_I1] = fd[1];
  85         error = fd[0];
  86 out:
  87         return error;
  88 }
  89
  90 int sparc_mmap_check(unsigned long addr, unsigned long len)
  91 {
  92         /* See asm-sparc/uaccess.h */
  93         if (len > TASK_SIZE - PAGE_SIZE || addr + len > TASK_SIZE - PAGE_SIZE)
  94                 return -EINVAL;
  95
  96         return 0;
  97 }
  98
  99 /* Linux version of mmap */
 100
 101 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 102         unsigned long prot, unsigned long flags, unsigned long fd,
 103         unsigned long pgoff)
 104 {
 105         /* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 106            we have. */
 107         return sys_mmap_pgoff(addr, len, prot, flags, fd,
 108                               pgoff >> (PAGE_SHIFT - 12));
 109 }
 110
 111 asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
 112         unsigned long prot, unsigned long flags, unsigned long fd,
 113         unsigned long off)
 114 {
 115         /* no alignment check? */
 116         return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 117 }
 118
 119 long sparc_remap_file_pages(unsigned long start, unsigned long size,
 120                            unsigned long prot, unsigned long pgoff,
 121                            unsigned long flags)
 122 {
 123         /* This works on an existing mmap so we don't need to validate
 124          * the range as that was done at the original mmap call.
 125          */
 126         return sys_remap_file_pages(start, size, prot,
 127                                     (pgoff >> (PAGE_SHIFT - 12)), flags);
 128 }
 129
 130 /* we come to here via sys_nis_syscall so it can setup the regs argument */
 131 asmlinkage unsigned long
 132 c_sys_nis_syscall (struct pt_regs *regs)
 133 {
 134         static int count = 0;
 135
 136         if (count++ > 5)
 137                 return -ENOSYS;
 138         printk ("%s[%d]: Unimplemented SPARC system call %d\n",
 139                 current->comm, task_pid_nr(current), (int)regs->u_regs[1]);
 140 #ifdef DEBUG_UNIMP_SYSCALL
 141         show_regs (regs);
 142 #endif
 143         return -ENOSYS;
 144 }
 145
 146 /* #define DEBUG_SPARC_BREAKPOINT */
 147
 148 asmlinkage void
 149 sparc_breakpoint (struct pt_regs *regs)
 150 {
 151         siginfo_t info;
 152
 153 #ifdef DEBUG_SPARC_BREAKPOINT
 154         printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
 155 #endif
 156         info.si_signo = SIGTRAP;
 157         info.si_errno = 0;
 158         info.si_code = TRAP_BRKPT;
 159         info.si_addr = (void __user *)regs->pc;
 160         info.si_trapno = 0;
 161         force_sig_info(SIGTRAP, &info, current);
 162
 163 #ifdef DEBUG_SPARC_BREAKPOINT
 164         printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);
 165 #endif
 166 }
 167
 168 SYSCALL_DEFINE3(sparc_sigaction, int, sig,
 169                 struct old_sigaction __user *,act,
 170                 struct old_sigaction __user *,oact)
 171 {
 172         WARN_ON_ONCE(sig >= 0);
 173         return sys_sigaction(-sig, act, oact);
 174 }
 175
 176 SYSCALL_DEFINE5(rt_sigaction, int, sig,
 177                  const struct sigaction __user *, act,
 178                  struct sigaction __user *, oact,
 179                  void __user *, restorer,
 180                  size_t, sigsetsize)
 181 {
 182         struct k_sigaction new_ka, old_ka;
 183         int ret;
 184
 185         /* XXX: Don't preclude handling different sized sigset_t's.  */
 186         if (sigsetsize != sizeof(sigset_t))
 187                 return -EINVAL;
 188
 189         if (act) {
 190                 new_ka.ka_restorer = restorer;
 191                 if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
 192                         return -EFAULT;
 193         }
 194
 195         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 196
 197         if (!ret && oact) {
 198                 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
 199                         return -EFAULT;
 200         }
 201
 202         return ret;
 203 }
 204
 205 asmlinkage long sys_getdomainname(char __user *name, int len)
 206 {
 207         int nlen, err;
 208
 209         if (len < 0)
 210                 return -EINVAL;
 211
 212         down_read(&uts_sem);
 213
 214         nlen = strlen(utsname()->domainname) + 1;
 215         err = -EINVAL;
 216         if (nlen > len)
 217                 goto out;
 218
 219         err = -EFAULT;
 220         if (!copy_to_user(name, utsname()->domainname, nlen))
 221                 err = 0;
 222
 223 out:
 224         up_read(&uts_sem);
 225         return err;
 226 }