arch/ia64/kernel/sys_ia64.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * This file contains various system calls that have different calling
   4  * conventions on different platforms.
   5  *
   6  * Copyright (C) 1999-2000, 2002-2003, 2005 Hewlett-Packard Co
   7  *      David Mosberger-Tang <davidm@hpl.hp.com>
   8  */
   9 #include <linux/errno.h>
  10 #include <linux/fs.h>
  11 #include <linux/mm.h>
  12 #include <linux/mman.h>
  13 #include <linux/sched.h>
  14 #include <linux/sched/mm.h>
  15 #include <linux/sched/task_stack.h>
  16 #include <linux/shm.h>
  17 #include <linux/file.h>         /* doh, must come after sched.h... */
  18 #include <linux/smp.h>
  19 #include <linux/syscalls.h>
  20 #include <linux/highuid.h>
  21 #include <linux/hugetlb.h>
  22
  23 #include <asm/shmparam.h>
  24 #include <linux/uaccess.h>
  25
  26 unsigned long
  27 arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len,
  28                         unsigned long pgoff, unsigned long flags)
  29 {
  30         long map_shared = (flags & MAP_SHARED);
  31         unsigned long align_mask = 0;
  32         struct mm_struct *mm = current->mm;
  33         struct vm_unmapped_area_info info;
  34
  35         if (len > RGN_MAP_LIMIT)
  36                 return -ENOMEM;
  37
  38         /* handle fixed mapping: prevent overlap with huge pages */
  39         if (flags & MAP_FIXED) {
  40                 if (is_hugepage_only_range(mm, addr, len))
  41                         return -EINVAL;
  42                 return addr;
  43         }
  44
  45 #ifdef CONFIG_HUGETLB_PAGE
  46         if (REGION_NUMBER(addr) == RGN_HPAGE)
  47                 addr = 0;
  48 #endif
  49         if (!addr)
  50                 addr = TASK_UNMAPPED_BASE;
  51
  52         if (map_shared && (TASK_SIZE > 0xfffffffful))
  53                 /*
  54                  * For 64-bit tasks, align shared segments to 1MB to avoid potential
  55                  * performance penalty due to virtual aliasing (see ASDM).  For 32-bit
  56                  * tasks, we prefer to avoid exhausting the address space too quickly by
  57                  * limiting alignment to a single page.
  58                  */
  59                 align_mask = PAGE_MASK & (SHMLBA - 1);
  60
  61         info.flags = 0;
  62         info.length = len;
  63         info.low_limit = addr;
  64         info.high_limit = TASK_SIZE;
  65         info.align_mask = align_mask;
  66         info.align_offset = 0;
  67         return vm_unmapped_area(&info);
  68 }
  69
  70 asmlinkage long
  71 ia64_getpriority (int which, int who)
  72 {
  73         long prio;
  74
  75         prio = sys_getpriority(which, who);
  76         if (prio >= 0) {
  77                 force_successful_syscall_return();
  78                 prio = 20 - prio;
  79         }
  80         return prio;
  81 }
  82
  83 /* XXX obsolete, but leave it here until the old libc is gone... */
  84 asmlinkage unsigned long
  85 sys_getpagesize (void)
  86 {
  87         return PAGE_SIZE;
  88 }
  89
  90 asmlinkage unsigned long
  91 ia64_brk (unsigned long brk)
  92 {
  93         unsigned long retval = sys_brk(brk);
  94         force_successful_syscall_return();
  95         return retval;
  96 }
  97
  98 /*
  99  * On IA-64, we return the two file descriptors in ret0 and ret1 (r8
 100  * and r9) as this is faster than doing a copy_to_user().
 101  */
 102 asmlinkage long
 103 sys_ia64_pipe (void)
 104 {
 105         struct pt_regs *regs = task_pt_regs(current);
 106         int fd[2];
 107         int retval;
 108
 109         retval = do_pipe_flags(fd, 0);
 110         if (retval)
 111                 goto out;
 112         retval = fd[0];
 113         regs->r9 = fd[1];
 114   out:
 115         return retval;
 116 }
 117
 118 int ia64_mmap_check(unsigned long addr, unsigned long len,
 119                 unsigned long flags)
 120 {
 121         unsigned long roff;
 122
 123         /*
 124          * Don't permit mappings into unmapped space, the virtual page table
 125          * of a region, or across a region boundary.  Note: RGN_MAP_LIMIT is
 126          * equal to 2^n-PAGE_SIZE (for some integer n <= 61) and len > 0.
 127          */
 128         roff = REGION_OFFSET(addr);
 129         if ((len > RGN_MAP_LIMIT) || (roff > (RGN_MAP_LIMIT - len)))
 130                 return -EINVAL;
 131         return 0;
 132 }
 133
 134 /*
 135  * mmap2() is like mmap() except that the offset is expressed in units
 136  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
 137  * of) files that are larger than the address space of the CPU.
 138  */
 139 asmlinkage unsigned long
 140 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
 141 {
 142         addr = ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 143         if (!IS_ERR((void *) addr))
 144                 force_successful_syscall_return();
 145         return addr;
 146 }
 147
 148 asmlinkage unsigned long
 149 sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, long off)
 150 {
 151         if (offset_in_page(off) != 0)
 152                 return -EINVAL;
 153
 154         addr = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 155         if (!IS_ERR((void *) addr))
 156                 force_successful_syscall_return();
 157         return addr;
 158 }
 159
 160 asmlinkage unsigned long
 161 ia64_mremap (unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags,
 162              unsigned long new_addr)
 163 {
 164         addr = sys_mremap(addr, old_len, new_len, flags, new_addr);
 165         if (!IS_ERR((void *) addr))
 166                 force_successful_syscall_return();
 167         return addr;
 168 }