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 <linux/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/sched/signal.h>
  34 #include <linux/sched/mm.h>
  35 #include <linux/shm.h>
  36 #include <linux/syscalls.h>
  37 #include <linux/utsname.h>
  38 #include <linux/personality.h>
  39 #include <linux/random.h>
  40
  41 /* we construct an artificial offset for the mapping based on the physical
  42  * address of the kernel mapping variable */
  43 #define GET_LAST_MMAP(filp)             \
  44         (filp ? ((unsigned long) filp->f_mapping) >> 8 : 0UL)
  45 #define SET_LAST_MMAP(filp, val)        \
  46          { /* nothing */ }
  47
  48 static int get_offset(unsigned int last_mmap)
  49 {
  50         return (last_mmap & (SHM_COLOUR-1)) >> PAGE_SHIFT;
  51 }
  52
  53 static unsigned long shared_align_offset(unsigned int last_mmap,
  54                                          unsigned long pgoff)
  55 {
  56         return (get_offset(last_mmap) + pgoff) << PAGE_SHIFT;
  57 }
  58
  59 static inline unsigned long COLOR_ALIGN(unsigned long addr,
  60                          unsigned int last_mmap, unsigned long pgoff)
  61 {
  62         unsigned long base = (addr+SHM_COLOUR-1) & ~(SHM_COLOUR-1);
  63         unsigned long off  = (SHM_COLOUR-1) &
  64                 (shared_align_offset(last_mmap, pgoff) << PAGE_SHIFT);
  65
  66         return base + off;
  67 }
  68
  69 /*
  70  * Top of mmap area (just below the process stack).
  71  */
  72
  73 /*
  74  * When called from arch_get_unmapped_area(), rlim_stack will be NULL,
  75  * indicating that "current" should be used instead of a passed-in
  76  * value from the exec bprm as done with arch_pick_mmap_layout().
  77  */
  78 static unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
  79 {
  80         unsigned long stack_base;
  81
  82         /* Limit stack size - see setup_arg_pages() in fs/exec.c */
  83         stack_base = rlim_stack ? rlim_stack->rlim_max
  84                                 : rlimit_max(RLIMIT_STACK);
  85         if (stack_base > STACK_SIZE_MAX)
  86                 stack_base = STACK_SIZE_MAX;
  87
  88         /* Add space for stack randomization. */
  89         if (current->flags & PF_RANDOMIZE)
  90                 stack_base += (STACK_RND_MASK << PAGE_SHIFT);
  91
  92         return PAGE_ALIGN(STACK_TOP - stack_base);
  93 }
  94
  95
  96 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  97                 unsigned long len, unsigned long pgoff, unsigned long flags)
  98 {
  99         struct mm_struct *mm = current->mm;
 100         struct vm_area_struct *vma, *prev;
 101         unsigned long task_size = TASK_SIZE;
 102         int do_color_align, last_mmap;
 103         struct vm_unmapped_area_info info;
 104
 105         if (len > task_size)
 106                 return -ENOMEM;
 107
 108         do_color_align = 0;
 109         if (filp || (flags & MAP_SHARED))
 110                 do_color_align = 1;
 111         last_mmap = GET_LAST_MMAP(filp);
 112
 113         if (flags & MAP_FIXED) {
 114                 if ((flags & MAP_SHARED) && last_mmap &&
 115                     (addr - shared_align_offset(last_mmap, pgoff))
 116                                 & (SHM_COLOUR - 1))
 117                         return -EINVAL;
 118                 goto found_addr;
 119         }
 120
 121         if (addr) {
 122                 if (do_color_align && last_mmap)
 123                         addr = COLOR_ALIGN(addr, last_mmap, pgoff);
 124                 else
 125                         addr = PAGE_ALIGN(addr);
 126
 127                 vma = find_vma_prev(mm, addr, &prev);
 128                 if (task_size - len >= addr &&
 129                     (!vma || addr + len <= vm_start_gap(vma)) &&
 130                     (!prev || addr >= vm_end_gap(prev)))
 131                         goto found_addr;
 132         }
 133
 134         info.flags = 0;
 135         info.length = len;
 136         info.low_limit = mm->mmap_legacy_base;
 137         info.high_limit = mmap_upper_limit(NULL);
 138         info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
 139         info.align_offset = shared_align_offset(last_mmap, pgoff);
 140         addr = vm_unmapped_area(&info);
 141
 142 found_addr:
 143         if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
 144                 SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
 145
 146         return addr;
 147 }
 148
 149 unsigned long
 150 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 151                           const unsigned long len, const unsigned long pgoff,
 152                           const unsigned long flags)
 153 {
 154         struct vm_area_struct *vma, *prev;
 155         struct mm_struct *mm = current->mm;
 156         unsigned long addr = addr0;
 157         int do_color_align, last_mmap;
 158         struct vm_unmapped_area_info info;
 159
 160         /* requested length too big for entire address space */
 161         if (len > TASK_SIZE)
 162                 return -ENOMEM;
 163
 164         do_color_align = 0;
 165         if (filp || (flags & MAP_SHARED))
 166                 do_color_align = 1;
 167         last_mmap = GET_LAST_MMAP(filp);
 168
 169         if (flags & MAP_FIXED) {
 170                 if ((flags & MAP_SHARED) && last_mmap &&
 171                     (addr - shared_align_offset(last_mmap, pgoff))
 172                         & (SHM_COLOUR - 1))
 173                         return -EINVAL;
 174                 goto found_addr;
 175         }
 176
 177         /* requesting a specific address */
 178         if (addr) {
 179                 if (do_color_align && last_mmap)
 180                         addr = COLOR_ALIGN(addr, last_mmap, pgoff);
 181                 else
 182                         addr = PAGE_ALIGN(addr);
 183
 184                 vma = find_vma_prev(mm, addr, &prev);
 185                 if (TASK_SIZE - len >= addr &&
 186                     (!vma || addr + len <= vm_start_gap(vma)) &&
 187                     (!prev || addr >= vm_end_gap(prev)))
 188                         goto found_addr;
 189         }
 190
 191         info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 192         info.length = len;
 193         info.low_limit = PAGE_SIZE;
 194         info.high_limit = mm->mmap_base;
 195         info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
 196         info.align_offset = shared_align_offset(last_mmap, pgoff);
 197         addr = vm_unmapped_area(&info);
 198         if (!(addr & ~PAGE_MASK))
 199                 goto found_addr;
 200         VM_BUG_ON(addr != -ENOMEM);
 201
 202         /*
 203          * A failed mmap() very likely causes application failure,
 204          * so fall back to the bottom-up function here. This scenario
 205          * can happen with large stack limits and large mmap()
 206          * allocations.
 207          */
 208         return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
 209
 210 found_addr:
 211         if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
 212                 SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
 213
 214         return addr;
 215 }
 216
 217 static int mmap_is_legacy(void)
 218 {
 219         if (current->personality & ADDR_COMPAT_LAYOUT)
 220                 return 1;
 221
 222         /* parisc stack always grows up - so a unlimited stack should
 223          * not be an indicator to use the legacy memory layout.
 224          * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
 225          *      return 1;
 226          */
 227
 228         return sysctl_legacy_va_layout;
 229 }
 230
 231 static unsigned long mmap_rnd(void)
 232 {
 233         unsigned long rnd = 0;
 234
 235         if (current->flags & PF_RANDOMIZE)
 236                 rnd = get_random_int() & MMAP_RND_MASK;
 237
 238         return rnd << PAGE_SHIFT;
 239 }
 240
 241 unsigned long arch_mmap_rnd(void)
 242 {
 243         return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
 244 }
 245
 246 static unsigned long mmap_legacy_base(void)
 247 {
 248         return TASK_UNMAPPED_BASE + mmap_rnd();
 249 }
 250
 251 /*
 252  * This function, called very early during the creation of a new
 253  * process VM image, sets up which VM layout function to use:
 254  */
 255 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
 256 {
 257         mm->mmap_legacy_base = mmap_legacy_base();
 258         mm->mmap_base = mmap_upper_limit(rlim_stack);
 259
 260         if (mmap_is_legacy()) {
 261                 mm->mmap_base = mm->mmap_legacy_base;
 262                 mm->get_unmapped_area = arch_get_unmapped_area;
 263         } else {
 264                 mm->get_unmapped_area = arch_get_unmapped_area_topdown;
 265         }
 266 }
 267
 268
 269 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 270         unsigned long prot, unsigned long flags, unsigned long fd,
 271         unsigned long pgoff)
 272 {
 273         /* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 274            we have. */
 275         return ksys_mmap_pgoff(addr, len, prot, flags, fd,
 276                                pgoff >> (PAGE_SHIFT - 12));
 277 }
 278
 279 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
 280                 unsigned long prot, unsigned long flags, unsigned long fd,
 281                 unsigned long offset)
 282 {
 283         if (!(offset & ~PAGE_MASK)) {
 284                 return ksys_mmap_pgoff(addr, len, prot, flags, fd,
 285                                         offset >> PAGE_SHIFT);
 286         } else {
 287                 return -EINVAL;
 288         }
 289 }
 290
 291 /* Fucking broken ABI */
 292
 293 #ifdef CONFIG_64BIT
 294 asmlinkage long parisc_truncate64(const char __user * path,
 295                                         unsigned int high, unsigned int low)
 296 {
 297         return ksys_truncate(path, (long)high << 32 | low);
 298 }
 299
 300 asmlinkage long parisc_ftruncate64(unsigned int fd,
 301                                         unsigned int high, unsigned int low)
 302 {
 303         return ksys_ftruncate(fd, (long)high << 32 | low);
 304 }
 305
 306 /* stubs for the benefit of the syscall_table since truncate64 and truncate
 307  * are identical on LP64 */
 308 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
 309 {
 310         return ksys_truncate(path, length);
 311 }
 312 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
 313 {
 314         return ksys_ftruncate(fd, length);
 315 }
 316 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
 317 {
 318         return sys_fcntl(fd, cmd, arg);
 319 }
 320 #else
 321
 322 asmlinkage long parisc_truncate64(const char __user * path,
 323                                         unsigned int high, unsigned int low)
 324 {
 325         return ksys_truncate(path, (loff_t)high << 32 | low);
 326 }
 327
 328 asmlinkage long parisc_ftruncate64(unsigned int fd,
 329                                         unsigned int high, unsigned int low)
 330 {
 331         return sys_ftruncate64(fd, (loff_t)high << 32 | low);
 332 }
 333 #endif
 334
 335 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
 336                                         unsigned int high, unsigned int low)
 337 {
 338         return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low);
 339 }
 340
 341 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
 342                         size_t count, unsigned int high, unsigned int low)
 343 {
 344         return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
 345 }
 346
 347 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
 348                                     size_t count)
 349 {
 350         return ksys_readahead(fd, (loff_t)high << 32 | low, count);
 351 }
 352
 353 asmlinkage long parisc_fadvise64_64(int fd,
 354                         unsigned int high_off, unsigned int low_off,
 355                         unsigned int high_len, unsigned int low_len, int advice)
 356 {
 357         return ksys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
 358                         (loff_t)high_len << 32 | low_len, advice);
 359 }
 360
 361 asmlinkage long parisc_sync_file_range(int fd,
 362                         u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
 363                         unsigned int flags)
 364 {
 365         return ksys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
 366                         (loff_t)hi_nbytes << 32 | lo_nbytes, flags);
 367 }
 368
 369 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
 370                                 u32 lenhi, u32 lenlo)
 371 {
 372         return ksys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
 373                               ((u64)lenhi << 32) | lenlo);
 374 }
 375
 376 long parisc_personality(unsigned long personality)
 377 {
 378         long err;
 379
 380         if (personality(current->personality) == PER_LINUX32
 381             && personality(personality) == PER_LINUX)
 382                 personality = (personality & ~PER_MASK) | PER_LINUX32;
 383
 384         err = sys_personality(personality);
 385         if (personality(err) == PER_LINUX32)
 386                 err = (err & ~PER_MASK) | PER_LINUX;
 387
 388         return err;
 389 }