arch/parisc/kernel/sys_parisc.c

   1
   2 /*
   3  *    PARISC specific syscalls
   4  *
   5  *    Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
   6  *    Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
   7  *    Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
   8  *    Copyright (C) 1999-2014 Helge Deller <deller@gmx.de>
   9  *
  10  *
  11  *    This program is free software; you can redistribute it and/or modify
  12  *    it under the terms of the GNU General Public License as published by
  13  *    the Free Software Foundation; either version 2 of the License, or
  14  *    (at your option) any later version.
  15  *
  16  *    This program is distributed in the hope that it will be useful,
  17  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *    GNU General Public License for more details.
  20  *
  21  *    You should have received a copy of the GNU General Public License
  22  *    along with this program; if not, write to the Free Software
  23  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24  */
  25
  26 #include <asm/uaccess.h>
  27 #include <asm/elf.h>
  28 #include <linux/file.h>
  29 #include <linux/fs.h>
  30 #include <linux/linkage.h>
  31 #include <linux/mm.h>
  32 #include <linux/mman.h>
  33 #include <linux/shm.h>
  34 #include <linux/syscalls.h>
  35 #include <linux/utsname.h>
  36 #include <linux/personality.h>
  37 #include <linux/random.h>
  38
  39 /* we construct an artificial offset for the mapping based on the physical
  40  * address of the kernel mapping variable */
  41 #define GET_LAST_MMAP(filp)             \
  42         (filp ? ((unsigned long) filp->f_mapping) >> 8 : 0UL)
  43 #define SET_LAST_MMAP(filp, val)        \
  44          { /* nothing */ }
  45
  46 static int get_offset(unsigned int last_mmap)
  47 {
  48         return (last_mmap & (SHM_COLOUR-1)) >> PAGE_SHIFT;
  49 }
  50
  51 static unsigned long shared_align_offset(unsigned int last_mmap,
  52                                          unsigned long pgoff)
  53 {
  54         return (get_offset(last_mmap) + pgoff) << PAGE_SHIFT;
  55 }
  56
  57 static inline unsigned long COLOR_ALIGN(unsigned long addr,
  58                          unsigned int last_mmap, unsigned long pgoff)
  59 {
  60         unsigned long base = (addr+SHM_COLOUR-1) & ~(SHM_COLOUR-1);
  61         unsigned long off  = (SHM_COLOUR-1) &
  62                 (shared_align_offset(last_mmap, pgoff) << PAGE_SHIFT);
  63
  64         return base + off;
  65 }
  66
  67 /*
  68  * Top of mmap area (just below the process stack).
  69  */
  70
  71 static unsigned long mmap_upper_limit(void)
  72 {
  73         unsigned long stack_base;
  74
  75         /* Limit stack size - see setup_arg_pages() in fs/exec.c */
  76         stack_base = rlimit_max(RLIMIT_STACK);
  77         if (stack_base > STACK_SIZE_MAX)
  78                 stack_base = STACK_SIZE_MAX;
  79
  80         /* Add space for stack randomization. */
  81         stack_base += (STACK_RND_MASK << PAGE_SHIFT);
  82
  83         return PAGE_ALIGN(STACK_TOP - stack_base);
  84 }
  85
  86
  87 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  88                 unsigned long len, unsigned long pgoff, unsigned long flags)
  89 {
  90         struct mm_struct *mm = current->mm;
  91         struct vm_area_struct *vma, *prev;
  92         unsigned long task_size = TASK_SIZE;
  93         int do_color_align, last_mmap;
  94         struct vm_unmapped_area_info info;
  95
  96         if (len > task_size)
  97                 return -ENOMEM;
  98
  99         do_color_align = 0;
 100         if (filp || (flags & MAP_SHARED))
 101                 do_color_align = 1;
 102         last_mmap = GET_LAST_MMAP(filp);
 103
 104         if (flags & MAP_FIXED) {
 105                 if ((flags & MAP_SHARED) && last_mmap &&
 106                     (addr - shared_align_offset(last_mmap, pgoff))
 107                                 & (SHM_COLOUR - 1))
 108                         return -EINVAL;
 109                 goto found_addr;
 110         }
 111
 112         if (addr) {
 113                 if (do_color_align && last_mmap)
 114                         addr = COLOR_ALIGN(addr, last_mmap, pgoff);
 115                 else
 116                         addr = PAGE_ALIGN(addr);
 117
 118                 vma = find_vma_prev(mm, addr, &prev);
 119                 if (task_size - len >= addr &&
 120                     (!vma || addr + len <= vm_start_gap(vma)) &&
 121                     (!prev || addr >= vm_end_gap(prev)))
 122                         goto found_addr;
 123         }
 124
 125         info.flags = 0;
 126         info.length = len;
 127         info.low_limit = mm->mmap_legacy_base;
 128         info.high_limit = mmap_upper_limit();
 129         info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
 130         info.align_offset = shared_align_offset(last_mmap, pgoff);
 131         addr = vm_unmapped_area(&info);
 132
 133 found_addr:
 134         if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
 135                 SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
 136
 137         return addr;
 138 }
 139
 140 unsigned long
 141 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 142                           const unsigned long len, const unsigned long pgoff,
 143                           const unsigned long flags)
 144 {
 145         struct vm_area_struct *vma, *prev;
 146         struct mm_struct *mm = current->mm;
 147         unsigned long addr = addr0;
 148         int do_color_align, last_mmap;
 149         struct vm_unmapped_area_info info;
 150
 151 #ifdef CONFIG_64BIT
 152         /* This should only ever run for 32-bit processes.  */
 153         BUG_ON(!test_thread_flag(TIF_32BIT));
 154 #endif
 155
 156         /* requested length too big for entire address space */
 157         if (len > TASK_SIZE)
 158                 return -ENOMEM;
 159
 160         do_color_align = 0;
 161         if (filp || (flags & MAP_SHARED))
 162                 do_color_align = 1;
 163         last_mmap = GET_LAST_MMAP(filp);
 164
 165         if (flags & MAP_FIXED) {
 166                 if ((flags & MAP_SHARED) && last_mmap &&
 167                     (addr - shared_align_offset(last_mmap, pgoff))
 168                         & (SHM_COLOUR - 1))
 169                         return -EINVAL;
 170                 goto found_addr;
 171         }
 172
 173         /* requesting a specific address */
 174         if (addr) {
 175                 if (do_color_align && last_mmap)
 176                         addr = COLOR_ALIGN(addr, last_mmap, pgoff);
 177                 else
 178                         addr = PAGE_ALIGN(addr);
 179
 180                 vma = find_vma_prev(mm, addr, &prev);
 181                 if (TASK_SIZE - len >= addr &&
 182                     (!vma || addr + len <= vm_start_gap(vma)) &&
 183                     (!prev || addr >= vm_end_gap(prev)))
 184                         goto found_addr;
 185         }
 186
 187         info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 188         info.length = len;
 189         info.low_limit = PAGE_SIZE;
 190         info.high_limit = mm->mmap_base;
 191         info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
 192         info.align_offset = shared_align_offset(last_mmap, pgoff);
 193         addr = vm_unmapped_area(&info);
 194         if (!(addr & ~PAGE_MASK))
 195                 goto found_addr;
 196         VM_BUG_ON(addr != -ENOMEM);
 197
 198         /*
 199          * A failed mmap() very likely causes application failure,
 200          * so fall back to the bottom-up function here. This scenario
 201          * can happen with large stack limits and large mmap()
 202          * allocations.
 203          */
 204         return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
 205
 206 found_addr:
 207         if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
 208                 SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
 209
 210         return addr;
 211 }
 212
 213 static int mmap_is_legacy(void)
 214 {
 215         if (current->personality & ADDR_COMPAT_LAYOUT)
 216                 return 1;
 217
 218         /* parisc stack always grows up - so a unlimited stack should
 219          * not be an indicator to use the legacy memory layout.
 220          * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
 221          *      return 1;
 222          */
 223
 224         return sysctl_legacy_va_layout;
 225 }
 226
 227 static unsigned long mmap_rnd(void)
 228 {
 229         unsigned long rnd = 0;
 230
 231         /*
 232         *  8 bits of randomness in 32bit mmaps, 20 address space bits
 233         * 28 bits of randomness in 64bit mmaps, 40 address space bits
 234         */
 235         if (current->flags & PF_RANDOMIZE) {
 236                 if (is_32bit_task())
 237                         rnd = get_random_int() % (1<<8);
 238                 else
 239                         rnd = get_random_int() % (1<<28);
 240         }
 241         return rnd << PAGE_SHIFT;
 242 }
 243
 244 static unsigned long mmap_legacy_base(void)
 245 {
 246         return TASK_UNMAPPED_BASE + mmap_rnd();
 247 }
 248
 249 /*
 250  * This function, called very early during the creation of a new
 251  * process VM image, sets up which VM layout function to use:
 252  */
 253 void arch_pick_mmap_layout(struct mm_struct *mm)
 254 {
 255         mm->mmap_legacy_base = mmap_legacy_base();
 256         mm->mmap_base = mmap_upper_limit();
 257
 258         if (mmap_is_legacy()) {
 259                 mm->mmap_base = mm->mmap_legacy_base;
 260                 mm->get_unmapped_area = arch_get_unmapped_area;
 261         } else {
 262                 mm->get_unmapped_area = arch_get_unmapped_area_topdown;
 263         }
 264 }
 265
 266
 267 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 268         unsigned long prot, unsigned long flags, unsigned long fd,
 269         unsigned long pgoff)
 270 {
 271         /* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 272            we have. */
 273         return sys_mmap_pgoff(addr, len, prot, flags, fd,
 274                               pgoff >> (PAGE_SHIFT - 12));
 275 }
 276
 277 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
 278                 unsigned long prot, unsigned long flags, unsigned long fd,
 279                 unsigned long offset)
 280 {
 281         if (!(offset & ~PAGE_MASK)) {
 282                 return sys_mmap_pgoff(addr, len, prot, flags, fd,
 283                                         offset >> PAGE_SHIFT);
 284         } else {
 285                 return -EINVAL;
 286         }
 287 }
 288
 289 /* Fucking broken ABI */
 290
 291 #ifdef CONFIG_64BIT
 292 asmlinkage long parisc_truncate64(const char __user * path,
 293                                         unsigned int high, unsigned int low)
 294 {
 295         return sys_truncate(path, (long)high << 32 | low);
 296 }
 297
 298 asmlinkage long parisc_ftruncate64(unsigned int fd,
 299                                         unsigned int high, unsigned int low)
 300 {
 301         return sys_ftruncate(fd, (long)high << 32 | low);
 302 }
 303
 304 /* stubs for the benefit of the syscall_table since truncate64 and truncate
 305  * are identical on LP64 */
 306 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
 307 {
 308         return sys_truncate(path, length);
 309 }
 310 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
 311 {
 312         return sys_ftruncate(fd, length);
 313 }
 314 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
 315 {
 316         return sys_fcntl(fd, cmd, arg);
 317 }
 318 #else
 319
 320 asmlinkage long parisc_truncate64(const char __user * path,
 321                                         unsigned int high, unsigned int low)
 322 {
 323         return sys_truncate64(path, (loff_t)high << 32 | low);
 324 }
 325
 326 asmlinkage long parisc_ftruncate64(unsigned int fd,
 327                                         unsigned int high, unsigned int low)
 328 {
 329         return sys_ftruncate64(fd, (loff_t)high << 32 | low);
 330 }
 331 #endif
 332
 333 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
 334                                         unsigned int high, unsigned int low)
 335 {
 336         return sys_pread64(fd, buf, count, (loff_t)high << 32 | low);
 337 }
 338
 339 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
 340                         size_t count, unsigned int high, unsigned int low)
 341 {
 342         return sys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
 343 }
 344
 345 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
 346                                     size_t count)
 347 {
 348         return sys_readahead(fd, (loff_t)high << 32 | low, count);
 349 }
 350
 351 asmlinkage long parisc_fadvise64_64(int fd,
 352                         unsigned int high_off, unsigned int low_off,
 353                         unsigned int high_len, unsigned int low_len, int advice)
 354 {
 355         return sys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
 356                         (loff_t)high_len << 32 | low_len, advice);
 357 }
 358
 359 asmlinkage long parisc_sync_file_range(int fd,
 360                         u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
 361                         unsigned int flags)
 362 {
 363         return sys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
 364                         (loff_t)hi_nbytes << 32 | lo_nbytes, flags);
 365 }
 366
 367 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
 368                                 u32 lenhi, u32 lenlo)
 369 {
 370         return sys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
 371                              ((u64)lenhi << 32) | lenlo);
 372 }
 373
 374 long parisc_personality(unsigned long personality)
 375 {
 376         long err;
 377
 378         if (personality(current->personality) == PER_LINUX32
 379             && personality(personality) == PER_LINUX)
 380                 personality = (personality & ~PER_MASK) | PER_LINUX32;
 381
 382         err = sys_personality(personality);
 383         if (personality(err) == PER_LINUX32)
 384                 err = (err & ~PER_MASK) | PER_LINUX;
 385
 386         return err;
 387 }