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