fs/nilfs2/ioctl.c

   1 /*
   2  * ioctl.c - NILFS ioctl operations.
   3  *
   4  * Copyright (C) 2007, 2008 Nippon Telegraph and Telephone Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * Written by Koji Sato <koji@osrg.net>.
  21  */
  22
  23 #include <linux/fs.h>
  24 #include <linux/wait.h>
  25 #include <linux/smp_lock.h>     /* lock_kernel(), unlock_kernel() */
  26 #include <linux/capability.h>   /* capable() */
  27 #include <linux/uaccess.h>      /* copy_from_user(), copy_to_user() */
  28 #include <linux/vmalloc.h>
  29 #include <linux/nilfs2_fs.h>
  30 #include "nilfs.h"
  31 #include "segment.h"
  32 #include "bmap.h"
  33 #include "cpfile.h"
  34 #include "sufile.h"
  35 #include "dat.h"
  36
  37
  38 static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
  39                                  struct nilfs_argv *argv, int dir,
  40                                  ssize_t (*dofunc)(struct the_nilfs *,
  41                                                    __u64 *, int,
  42                                                    void *, size_t, size_t))
  43 {
  44         void *buf;
  45         void __user *base = (void __user *)(unsigned long)argv->v_base;
  46         size_t maxmembs, total, n;
  47         ssize_t nr;
  48         int ret, i;
  49         __u64 pos, ppos;
  50
  51         if (argv->v_nmembs == 0)
  52                 return 0;
  53
  54         if (argv->v_size > PAGE_SIZE)
  55                 return -EINVAL;
  56
  57         buf = (void *)__get_free_pages(GFP_NOFS, 0);
  58         if (unlikely(!buf))
  59                 return -ENOMEM;
  60         maxmembs = PAGE_SIZE / argv->v_size;
  61
  62         ret = 0;
  63         total = 0;
  64         pos = argv->v_index;
  65         for (i = 0; i < argv->v_nmembs; i += n) {
  66                 n = (argv->v_nmembs - i < maxmembs) ?
  67                         argv->v_nmembs - i : maxmembs;
  68                 if ((dir & _IOC_WRITE) &&
  69                     copy_from_user(buf, base + argv->v_size * i,
  70                                    argv->v_size * n)) {
  71                         ret = -EFAULT;
  72                         break;
  73                 }
  74                 ppos = pos;
  75                 nr = dofunc(nilfs, &pos, argv->v_flags, buf, argv->v_size,
  76                                n);
  77                 if (nr < 0) {
  78                         ret = nr;
  79                         break;
  80                 }
  81                 if ((dir & _IOC_READ) &&
  82                     copy_to_user(base + argv->v_size * i, buf,
  83                                  argv->v_size * nr)) {
  84                         ret = -EFAULT;
  85                         break;
  86                 }
  87                 total += nr;
  88                 if ((size_t)nr < n)
  89                         break;
  90                 if (pos == ppos)
  91                         pos += n;
  92         }
  93         argv->v_nmembs = total;
  94
  95         free_pages((unsigned long)buf, 0);
  96         return ret;
  97 }
  98
  99 static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
 100                                      unsigned int cmd, void __user *argp)
 101 {
 102         struct inode *cpfile = NILFS_SB(inode->i_sb)->s_nilfs->ns_cpfile;
 103         struct nilfs_transaction_info ti;
 104         struct nilfs_cpmode cpmode;
 105         int ret;
 106
 107         if (!capable(CAP_SYS_ADMIN))
 108                 return -EPERM;
 109         if (copy_from_user(&cpmode, argp, sizeof(cpmode)))
 110                 return -EFAULT;
 111
 112         nilfs_transaction_begin(inode->i_sb, &ti, 0);
 113         ret = nilfs_cpfile_change_cpmode(
 114                 cpfile, cpmode.cm_cno, cpmode.cm_mode);
 115         if (unlikely(ret < 0)) {
 116                 nilfs_transaction_abort(inode->i_sb);
 117                 return ret;
 118         }
 119         nilfs_transaction_commit(inode->i_sb); /* never fails */
 120         return ret;
 121 }
 122
 123 static int
 124 nilfs_ioctl_delete_checkpoint(struct inode *inode, struct file *filp,
 125                               unsigned int cmd, void __user *argp)
 126 {
 127         struct inode *cpfile = NILFS_SB(inode->i_sb)->s_nilfs->ns_cpfile;
 128         struct nilfs_transaction_info ti;
 129         __u64 cno;
 130         int ret;
 131
 132         if (!capable(CAP_SYS_ADMIN))
 133                 return -EPERM;
 134         if (copy_from_user(&cno, argp, sizeof(cno)))
 135                 return -EFAULT;
 136
 137         nilfs_transaction_begin(inode->i_sb, &ti, 0);
 138         ret = nilfs_cpfile_delete_checkpoint(cpfile, cno);
 139         if (unlikely(ret < 0)) {
 140                 nilfs_transaction_abort(inode->i_sb);
 141                 return ret;
 142         }
 143         nilfs_transaction_commit(inode->i_sb); /* never fails */
 144         return ret;
 145 }
 146
 147 static ssize_t
 148 nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
 149                           void *buf, size_t size, size_t nmembs)
 150 {
 151         int ret;
 152
 153         down_read(&nilfs->ns_segctor_sem);
 154         ret = nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
 155                                       nmembs);
 156         up_read(&nilfs->ns_segctor_sem);
 157         return ret;
 158 }
 159
 160 static int nilfs_ioctl_get_cpstat(struct inode *inode, struct file *filp,
 161                                   unsigned int cmd, void __user *argp)
 162 {
 163         struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
 164         struct nilfs_cpstat cpstat;
 165         int ret;
 166
 167         down_read(&nilfs->ns_segctor_sem);
 168         ret = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
 169         up_read(&nilfs->ns_segctor_sem);
 170         if (ret < 0)
 171                 return ret;
 172
 173         if (copy_to_user(argp, &cpstat, sizeof(cpstat)))
 174                 ret = -EFAULT;
 175         return ret;
 176 }
 177
 178 static ssize_t
 179 nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
 180                           void *buf, size_t size, size_t nmembs)
 181 {
 182         int ret;
 183
 184         down_read(&nilfs->ns_segctor_sem);
 185         ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, nmembs);
 186         up_read(&nilfs->ns_segctor_sem);
 187         return ret;
 188 }
 189
 190 static int nilfs_ioctl_get_sustat(struct inode *inode, struct file *filp,
 191                                   unsigned int cmd, void __user *argp)
 192 {
 193         struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
 194         struct nilfs_sustat sustat;
 195         int ret;
 196
 197         down_read(&nilfs->ns_segctor_sem);
 198         ret = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
 199         up_read(&nilfs->ns_segctor_sem);
 200         if (ret < 0)
 201                 return ret;
 202
 203         if (copy_to_user(argp, &sustat, sizeof(sustat)))
 204                 ret = -EFAULT;
 205         return ret;
 206 }
 207
 208 static ssize_t
 209 nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
 210                          void *buf, size_t size, size_t nmembs)
 211 {
 212         int ret;
 213
 214         down_read(&nilfs->ns_segctor_sem);
 215         ret = nilfs_dat_get_vinfo(nilfs_dat_inode(nilfs), buf, nmembs);
 216         up_read(&nilfs->ns_segctor_sem);
 217         return ret;
 218 }
 219
 220 static ssize_t
 221 nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
 222                           void *buf, size_t size, size_t nmembs)
 223 {
 224         struct inode *dat = nilfs_dat_inode(nilfs);
 225         struct nilfs_bmap *bmap = NILFS_I(dat)->i_bmap;
 226         struct nilfs_bdesc *bdescs = buf;
 227         int ret, i;
 228
 229         down_read(&nilfs->ns_segctor_sem);
 230         for (i = 0; i < nmembs; i++) {
 231                 ret = nilfs_bmap_lookup_at_level(bmap,
 232                                                  bdescs[i].bd_offset,
 233                                                  bdescs[i].bd_level + 1,
 234                                                  &bdescs[i].bd_blocknr);
 235                 if (ret < 0) {
 236                         if (ret != -ENOENT) {
 237                                 up_read(&nilfs->ns_segctor_sem);
 238                                 return ret;
 239                         }
 240                         bdescs[i].bd_blocknr = 0;
 241                 }
 242         }
 243         up_read(&nilfs->ns_segctor_sem);
 244         return nmembs;
 245 }
 246
 247 static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
 248                                   unsigned int cmd, void __user *argp)
 249 {
 250         struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
 251         struct nilfs_argv argv;
 252         int ret;
 253
 254         if (copy_from_user(&argv, argp, sizeof(argv)))
 255                 return -EFAULT;
 256
 257         if (argv.v_size != sizeof(struct nilfs_bdesc))
 258                 return -EINVAL;
 259
 260         ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
 261                                     nilfs_ioctl_do_get_bdescs);
 262         if (ret < 0)
 263                 return ret;
 264
 265         if (copy_to_user(argp, &argv, sizeof(argv)))
 266                 ret = -EFAULT;
 267         return ret;
 268 }
 269
 270 static int nilfs_ioctl_move_inode_block(struct inode *inode,
 271                                         struct nilfs_vdesc *vdesc,
 272                                         struct list_head *buffers)
 273 {
 274         struct buffer_head *bh;
 275         int ret;
 276
 277         if (vdesc->vd_flags == 0)
 278                 ret = nilfs_gccache_submit_read_data(
 279                         inode, vdesc->vd_offset, vdesc->vd_blocknr,
 280                         vdesc->vd_vblocknr, &bh);
 281         else
 282                 ret = nilfs_gccache_submit_read_node(
 283                         inode, vdesc->vd_blocknr, vdesc->vd_vblocknr, &bh);
 284
 285         if (unlikely(ret < 0)) {
 286                 if (ret == -ENOENT)
 287                         printk(KERN_CRIT
 288                                "%s: invalid virtual block address (%s): "
 289                                "ino=%llu, cno=%llu, offset=%llu, "
 290                                "blocknr=%llu, vblocknr=%llu\n",
 291                                __func__, vdesc->vd_flags ? "node" : "data",
 292                                (unsigned long long)vdesc->vd_ino,
 293                                (unsigned long long)vdesc->vd_cno,
 294                                (unsigned long long)vdesc->vd_offset,
 295                                (unsigned long long)vdesc->vd_blocknr,
 296                                (unsigned long long)vdesc->vd_vblocknr);
 297                 return ret;
 298         }
 299         bh->b_private = vdesc;
 300         list_add_tail(&bh->b_assoc_buffers, buffers);
 301         return 0;
 302 }
 303
 304 static int nilfs_ioctl_move_blocks(struct the_nilfs *nilfs,
 305                                    struct nilfs_argv *argv, void *buf)
 306 {
 307         size_t nmembs = argv->v_nmembs;
 308         struct inode *inode;
 309         struct nilfs_vdesc *vdesc;
 310         struct buffer_head *bh, *n;
 311         LIST_HEAD(buffers);
 312         ino_t ino;
 313         __u64 cno;
 314         int i, ret;
 315
 316         for (i = 0, vdesc = buf; i < nmembs; ) {
 317                 ino = vdesc->vd_ino;
 318                 cno = vdesc->vd_cno;
 319                 inode = nilfs_gc_iget(nilfs, ino, cno);
 320                 if (unlikely(inode == NULL)) {
 321                         ret = -ENOMEM;
 322                         goto failed;
 323                 }
 324                 do {
 325                         ret = nilfs_ioctl_move_inode_block(inode, vdesc,
 326                                                            &buffers);
 327                         if (unlikely(ret < 0))
 328                                 goto failed;
 329                         vdesc++;
 330                 } while (++i < nmembs &&
 331                          vdesc->vd_ino == ino && vdesc->vd_cno == cno);
 332         }
 333
 334         list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
 335                 ret = nilfs_gccache_wait_and_mark_dirty(bh);
 336                 if (unlikely(ret < 0)) {
 337                         if (ret == -EEXIST) {
 338                                 vdesc = bh->b_private;
 339                                 printk(KERN_CRIT
 340                                        "%s: conflicting %s buffer: "
 341                                        "ino=%llu, cno=%llu, offset=%llu, "
 342                                        "blocknr=%llu, vblocknr=%llu\n",
 343                                        __func__,
 344                                        vdesc->vd_flags ? "node" : "data",
 345                                        (unsigned long long)vdesc->vd_ino,
 346                                        (unsigned long long)vdesc->vd_cno,
 347                                        (unsigned long long)vdesc->vd_offset,
 348                                        (unsigned long long)vdesc->vd_blocknr,
 349                                        (unsigned long long)vdesc->vd_vblocknr);
 350                         }
 351                         goto failed;
 352                 }
 353                 list_del_init(&bh->b_assoc_buffers);
 354                 bh->b_private = NULL;
 355                 brelse(bh);
 356         }
 357         return nmembs;
 358
 359  failed:
 360         list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
 361                 list_del_init(&bh->b_assoc_buffers);
 362                 bh->b_private = NULL;
 363                 brelse(bh);
 364         }
 365         return ret;
 366 }
 367
 368 static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
 369                                           struct nilfs_argv *argv, void *buf)
 370 {
 371         size_t nmembs = argv->v_nmembs;
 372         struct inode *cpfile = nilfs->ns_cpfile;
 373         struct nilfs_period *periods = buf;
 374         int ret, i;
 375
 376         for (i = 0; i < nmembs; i++) {
 377                 ret = nilfs_cpfile_delete_checkpoints(
 378                         cpfile, periods[i].p_start, periods[i].p_end);
 379                 if (ret < 0)
 380                         return ret;
 381         }
 382         return nmembs;
 383 }
 384
 385 static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
 386                                       struct nilfs_argv *argv, void *buf)
 387 {
 388         size_t nmembs = argv->v_nmembs;
 389         int ret;
 390
 391         ret = nilfs_dat_freev(nilfs_dat_inode(nilfs), buf, nmembs);
 392
 393         return (ret < 0) ? ret : nmembs;
 394 }
 395
 396 static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
 397                                          struct nilfs_argv *argv, void *buf)
 398 {
 399         size_t nmembs = argv->v_nmembs;
 400         struct inode *dat = nilfs_dat_inode(nilfs);
 401         struct nilfs_bmap *bmap = NILFS_I(dat)->i_bmap;
 402         struct nilfs_bdesc *bdescs = buf;
 403         int ret, i;
 404
 405         for (i = 0; i < nmembs; i++) {
 406                 /* XXX: use macro or inline func to check liveness */
 407                 ret = nilfs_bmap_lookup_at_level(bmap,
 408                                                  bdescs[i].bd_offset,
 409                                                  bdescs[i].bd_level + 1,
 410                                                  &bdescs[i].bd_blocknr);
 411                 if (ret < 0) {
 412                         if (ret != -ENOENT)
 413                                 return ret;
 414                         bdescs[i].bd_blocknr = 0;
 415                 }
 416                 if (bdescs[i].bd_blocknr != bdescs[i].bd_oblocknr)
 417                         /* skip dead block */
 418                         continue;
 419                 if (bdescs[i].bd_level == 0) {
 420                         ret = nilfs_mdt_mark_block_dirty(dat,
 421                                                          bdescs[i].bd_offset);
 422                         if (ret < 0) {
 423                                 WARN_ON(ret == -ENOENT);
 424                                 return ret;
 425                         }
 426                 } else {
 427                         ret = nilfs_bmap_mark(bmap, bdescs[i].bd_offset,
 428                                               bdescs[i].bd_level);
 429                         if (ret < 0) {
 430                                 WARN_ON(ret == -ENOENT);
 431                                 return ret;
 432                         }
 433                 }
 434         }
 435         return nmembs;
 436 }
 437
 438 static int nilfs_ioctl_free_segments(struct the_nilfs *nilfs,
 439                                      struct nilfs_argv *argv, void *buf)
 440 {
 441         size_t nmembs = argv->v_nmembs;
 442         struct nilfs_sb_info *sbi = nilfs->ns_writer;
 443         int ret;
 444
 445         if (unlikely(!sbi)) {
 446                 /* never happens because called for a writable mount */
 447                 WARN_ON(1);
 448                 return -EROFS;
 449         }
 450         ret = nilfs_segctor_add_segments_to_be_freed(
 451                 NILFS_SC(sbi), buf, nmembs);
 452
 453         return (ret < 0) ? ret : nmembs;
 454 }
 455
 456 int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
 457                                        struct nilfs_argv *argv, void **kbufs)
 458 {
 459         const char *msg;
 460         int ret;
 461
 462         ret = nilfs_ioctl_move_blocks(nilfs, &argv[0], kbufs[0]);
 463         if (ret < 0) {
 464                 msg = "cannot read source blocks";
 465                 goto failed;
 466         }
 467
 468         ret = nilfs_ioctl_delete_checkpoints(nilfs, &argv[1], kbufs[1]);
 469         if (ret < 0) {
 470                 /*
 471                  * can safely abort because checkpoints can be removed
 472                  * independently.
 473                  */
 474                 msg = "cannot delete checkpoints";
 475                 goto failed;
 476         }
 477         ret = nilfs_ioctl_free_vblocknrs(nilfs, &argv[2], kbufs[2]);
 478         if (ret < 0) {
 479                 /*
 480                  * can safely abort because DAT file is updated atomically
 481                  * using a copy-on-write technique.
 482                  */
 483                 msg = "cannot delete virtual blocks from DAT file";
 484                 goto failed;
 485         }
 486         ret = nilfs_ioctl_mark_blocks_dirty(nilfs, &argv[3], kbufs[3]);
 487         if (ret < 0) {
 488                 /*
 489                  * can safely abort because the operation is nondestructive.
 490                  */
 491                 msg = "cannot mark copying blocks dirty";
 492                 goto failed;
 493         }
 494         ret = nilfs_ioctl_free_segments(nilfs, &argv[4], kbufs[4]);
 495         if (ret < 0) {
 496                 /*
 497                  * can safely abort because this operation is atomic.
 498                  */
 499                 msg = "cannot set segments to be freed";
 500                 goto failed;
 501         }
 502         return 0;
 503
 504  failed:
 505         nilfs_remove_all_gcinode(nilfs);
 506         printk(KERN_ERR "NILFS: GC failed during preparation: %s: err=%d\n",
 507                msg, ret);
 508         return ret;
 509 }
 510
 511 static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
 512                                       unsigned int cmd, void __user *argp)
 513 {
 514         struct nilfs_argv argv[5];
 515         const static size_t argsz[5] = {
 516                 sizeof(struct nilfs_vdesc),
 517                 sizeof(struct nilfs_period),
 518                 sizeof(__u64),
 519                 sizeof(struct nilfs_bdesc),
 520                 sizeof(__u64),
 521         };
 522         void __user *base;
 523         void *kbufs[5];
 524         struct the_nilfs *nilfs;
 525         size_t len, nsegs;
 526         int n, ret;
 527
 528         if (!capable(CAP_SYS_ADMIN))
 529                 return -EPERM;
 530
 531         if (copy_from_user(argv, argp, sizeof(argv)))
 532                 return -EFAULT;
 533
 534         nsegs = argv[4].v_nmembs;
 535         if (argv[4].v_size != argsz[4])
 536                 return -EINVAL;
 537         /*
 538          * argv[4] points to segment numbers this ioctl cleans.  We
 539          * use kmalloc() for its buffer because memory used for the
 540          * segment numbers is enough small.
 541          */
 542         kbufs[4] = memdup_user((void __user *)(unsigned long)argv[4].v_base,
 543                                nsegs * sizeof(__u64));
 544         if (IS_ERR(kbufs[4]))
 545                 return PTR_ERR(kbufs[4]);
 546
 547         nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
 548
 549         for (n = 0; n < 4; n++) {
 550                 ret = -EINVAL;
 551                 if (argv[n].v_size != argsz[n])
 552                         goto out_free;
 553
 554                 if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
 555                         goto out_free;
 556
 557                 len = argv[n].v_size * argv[n].v_nmembs;
 558                 base = (void __user *)(unsigned long)argv[n].v_base;
 559                 if (len == 0) {
 560                         kbufs[n] = NULL;
 561                         continue;
 562                 }
 563
 564                 kbufs[n] = vmalloc(len);
 565                 if (!kbufs[n]) {
 566                         ret = -ENOMEM;
 567                         goto out_free;
 568                 }
 569                 if (copy_from_user(kbufs[n], base, len)) {
 570                         ret = -EFAULT;
 571                         vfree(kbufs[n]);
 572                         goto out_free;
 573                 }
 574         }
 575
 576         ret = nilfs_clean_segments(inode->i_sb, argv, kbufs);
 577
 578  out_free:
 579         while (--n >= 0)
 580                 vfree(kbufs[n]);
 581         kfree(kbufs[4]);
 582         return ret;
 583 }
 584
 585 static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
 586                             unsigned int cmd, void __user *argp)
 587 {
 588         __u64 cno;
 589         int ret;
 590
 591         ret = nilfs_construct_segment(inode->i_sb);
 592         if (ret < 0)
 593                 return ret;
 594
 595         if (argp != NULL) {
 596                 cno = NILFS_SB(inode->i_sb)->s_nilfs->ns_cno - 1;
 597                 if (copy_to_user(argp, &cno, sizeof(cno)))
 598                         return -EFAULT;
 599         }
 600         return 0;
 601 }
 602
 603 static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
 604                                 unsigned int cmd, void __user *argp,
 605                                 size_t membsz,
 606                                 ssize_t (*dofunc)(struct the_nilfs *,
 607                                                   __u64 *, int,
 608                                                   void *, size_t, size_t))
 609
 610 {
 611         struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
 612         struct nilfs_argv argv;
 613         int ret;
 614
 615         if (copy_from_user(&argv, argp, sizeof(argv)))
 616                 return -EFAULT;
 617
 618         if (argv.v_size != membsz)
 619                 return -EINVAL;
 620
 621         ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd), dofunc);
 622         if (ret < 0)
 623                 return ret;
 624
 625         if (copy_to_user(argp, &argv, sizeof(argv)))
 626                 ret = -EFAULT;
 627         return ret;
 628 }
 629
 630 long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 631 {
 632         struct inode *inode = filp->f_dentry->d_inode;
 633         void __user *argp = (void * __user *)arg;
 634
 635         switch (cmd) {
 636         case NILFS_IOCTL_CHANGE_CPMODE:
 637                 return nilfs_ioctl_change_cpmode(inode, filp, cmd, argp);
 638         case NILFS_IOCTL_DELETE_CHECKPOINT:
 639                 return nilfs_ioctl_delete_checkpoint(inode, filp, cmd, argp);
 640         case NILFS_IOCTL_GET_CPINFO:
 641                 return nilfs_ioctl_get_info(inode, filp, cmd, argp,
 642                                             sizeof(struct nilfs_cpinfo),
 643                                             nilfs_ioctl_do_get_cpinfo);
 644         case NILFS_IOCTL_GET_CPSTAT:
 645                 return nilfs_ioctl_get_cpstat(inode, filp, cmd, argp);
 646         case NILFS_IOCTL_GET_SUINFO:
 647                 return nilfs_ioctl_get_info(inode, filp, cmd, argp,
 648                                             sizeof(struct nilfs_suinfo),
 649                                             nilfs_ioctl_do_get_suinfo);
 650         case NILFS_IOCTL_GET_SUSTAT:
 651                 return nilfs_ioctl_get_sustat(inode, filp, cmd, argp);
 652         case NILFS_IOCTL_GET_VINFO:
 653                 return nilfs_ioctl_get_info(inode, filp, cmd, argp,
 654                                             sizeof(struct nilfs_vinfo),
 655                                             nilfs_ioctl_do_get_vinfo);
 656         case NILFS_IOCTL_GET_BDESCS:
 657                 return nilfs_ioctl_get_bdescs(inode, filp, cmd, argp);
 658         case NILFS_IOCTL_CLEAN_SEGMENTS:
 659                 return nilfs_ioctl_clean_segments(inode, filp, cmd, argp);
 660         case NILFS_IOCTL_SYNC:
 661                 return nilfs_ioctl_sync(inode, filp, cmd, argp);
 662         default:
 663                 return -ENOTTY;
 664         }
 665 }