fs/f2fs/super.c

   1 /*
   2  * fs/f2fs/super.c
   3  *
   4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5  *             http://www.samsung.com/
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/fs.h>
  14 #include <linux/statfs.h>
  15 #include <linux/buffer_head.h>
  16 #include <linux/backing-dev.h>
  17 #include <linux/kthread.h>
  18 #include <linux/parser.h>
  19 #include <linux/mount.h>
  20 #include <linux/seq_file.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/random.h>
  23 #include <linux/exportfs.h>
  24 #include <linux/blkdev.h>
  25 #include <linux/f2fs_fs.h>
  26 #include <linux/sysfs.h>
  27
  28 #include "f2fs.h"
  29 #include "node.h"
  30 #include "segment.h"
  31 #include "xattr.h"
  32 #include "gc.h"
  33 #include "trace.h"
  34
  35 #define CREATE_TRACE_POINTS
  36 #include <trace/events/f2fs.h>
  37
  38 static struct proc_dir_entry *f2fs_proc_root;
  39 static struct kmem_cache *f2fs_inode_cachep;
  40 static struct kset *f2fs_kset;
  41
  42 enum {
  43         Opt_gc_background,
  44         Opt_disable_roll_forward,
  45         Opt_norecovery,
  46         Opt_discard,
  47         Opt_noheap,
  48         Opt_user_xattr,
  49         Opt_nouser_xattr,
  50         Opt_acl,
  51         Opt_noacl,
  52         Opt_active_logs,
  53         Opt_disable_ext_identify,
  54         Opt_inline_xattr,
  55         Opt_inline_data,
  56         Opt_inline_dentry,
  57         Opt_flush_merge,
  58         Opt_nobarrier,
  59         Opt_fastboot,
  60         Opt_err,
  61 };
  62
  63 static match_table_t f2fs_tokens = {
  64         {Opt_gc_background, "background_gc=%s"},
  65         {Opt_disable_roll_forward, "disable_roll_forward"},
  66         {Opt_norecovery, "norecovery"},
  67         {Opt_discard, "discard"},
  68         {Opt_noheap, "no_heap"},
  69         {Opt_user_xattr, "user_xattr"},
  70         {Opt_nouser_xattr, "nouser_xattr"},
  71         {Opt_acl, "acl"},
  72         {Opt_noacl, "noacl"},
  73         {Opt_active_logs, "active_logs=%u"},
  74         {Opt_disable_ext_identify, "disable_ext_identify"},
  75         {Opt_inline_xattr, "inline_xattr"},
  76         {Opt_inline_data, "inline_data"},
  77         {Opt_inline_dentry, "inline_dentry"},
  78         {Opt_flush_merge, "flush_merge"},
  79         {Opt_nobarrier, "nobarrier"},
  80         {Opt_fastboot, "fastboot"},
  81         {Opt_err, NULL},
  82 };
  83
  84 /* Sysfs support for f2fs */
  85 enum {
  86         GC_THREAD,      /* struct f2fs_gc_thread */
  87         SM_INFO,        /* struct f2fs_sm_info */
  88         NM_INFO,        /* struct f2fs_nm_info */
  89         F2FS_SBI,       /* struct f2fs_sb_info */
  90 };
  91
  92 struct f2fs_attr {
  93         struct attribute attr;
  94         ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
  95         ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
  96                          const char *, size_t);
  97         int struct_type;
  98         int offset;
  99 };
 100
 101 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
 102 {
 103         if (struct_type == GC_THREAD)
 104                 return (unsigned char *)sbi->gc_thread;
 105         else if (struct_type == SM_INFO)
 106                 return (unsigned char *)SM_I(sbi);
 107         else if (struct_type == NM_INFO)
 108                 return (unsigned char *)NM_I(sbi);
 109         else if (struct_type == F2FS_SBI)
 110                 return (unsigned char *)sbi;
 111         return NULL;
 112 }
 113
 114 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 115                         struct f2fs_sb_info *sbi, char *buf)
 116 {
 117         unsigned char *ptr = NULL;
 118         unsigned int *ui;
 119
 120         ptr = __struct_ptr(sbi, a->struct_type);
 121         if (!ptr)
 122                 return -EINVAL;
 123
 124         ui = (unsigned int *)(ptr + a->offset);
 125
 126         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
 127 }
 128
 129 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
 130                         struct f2fs_sb_info *sbi,
 131                         const char *buf, size_t count)
 132 {
 133         unsigned char *ptr;
 134         unsigned long t;
 135         unsigned int *ui;
 136         ssize_t ret;
 137
 138         ptr = __struct_ptr(sbi, a->struct_type);
 139         if (!ptr)
 140                 return -EINVAL;
 141
 142         ui = (unsigned int *)(ptr + a->offset);
 143
 144         ret = kstrtoul(skip_spaces(buf), 0, &t);
 145         if (ret < 0)
 146                 return ret;
 147         *ui = t;
 148         return count;
 149 }
 150
 151 static ssize_t f2fs_attr_show(struct kobject *kobj,
 152                                 struct attribute *attr, char *buf)
 153 {
 154         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 155                                                                 s_kobj);
 156         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 157
 158         return a->show ? a->show(a, sbi, buf) : 0;
 159 }
 160
 161 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
 162                                                 const char *buf, size_t len)
 163 {
 164         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 165                                                                         s_kobj);
 166         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 167
 168         return a->store ? a->store(a, sbi, buf, len) : 0;
 169 }
 170
 171 static void f2fs_sb_release(struct kobject *kobj)
 172 {
 173         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 174                                                                 s_kobj);
 175         complete(&sbi->s_kobj_unregister);
 176 }
 177
 178 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
 179 static struct f2fs_attr f2fs_attr_##_name = {                   \
 180         .attr = {.name = __stringify(_name), .mode = _mode },   \
 181         .show   = _show,                                        \
 182         .store  = _store,                                       \
 183         .struct_type = _struct_type,                            \
 184         .offset = _offset                                       \
 185 }
 186
 187 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)    \
 188         F2FS_ATTR_OFFSET(struct_type, name, 0644,               \
 189                 f2fs_sbi_show, f2fs_sbi_store,                  \
 190                 offsetof(struct struct_name, elname))
 191
 192 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
 193 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
 194 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
 195 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
 196 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
 197 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
 198 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
 199 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
 200 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
 201 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
 202 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
 203 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
 204
 205 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 206 static struct attribute *f2fs_attrs[] = {
 207         ATTR_LIST(gc_min_sleep_time),
 208         ATTR_LIST(gc_max_sleep_time),
 209         ATTR_LIST(gc_no_gc_sleep_time),
 210         ATTR_LIST(gc_idle),
 211         ATTR_LIST(reclaim_segments),
 212         ATTR_LIST(max_small_discards),
 213         ATTR_LIST(ipu_policy),
 214         ATTR_LIST(min_ipu_util),
 215         ATTR_LIST(min_fsync_blocks),
 216         ATTR_LIST(max_victim_search),
 217         ATTR_LIST(dir_level),
 218         ATTR_LIST(ram_thresh),
 219         NULL,
 220 };
 221
 222 static const struct sysfs_ops f2fs_attr_ops = {
 223         .show   = f2fs_attr_show,
 224         .store  = f2fs_attr_store,
 225 };
 226
 227 static struct kobj_type f2fs_ktype = {
 228         .default_attrs  = f2fs_attrs,
 229         .sysfs_ops      = &f2fs_attr_ops,
 230         .release        = f2fs_sb_release,
 231 };
 232
 233 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
 234 {
 235         struct va_format vaf;
 236         va_list args;
 237
 238         va_start(args, fmt);
 239         vaf.fmt = fmt;
 240         vaf.va = &args;
 241         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
 242         va_end(args);
 243 }
 244
 245 static void init_once(void *foo)
 246 {
 247         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
 248
 249         inode_init_once(&fi->vfs_inode);
 250 }
 251
 252 static int parse_options(struct super_block *sb, char *options)
 253 {
 254         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 255         substring_t args[MAX_OPT_ARGS];
 256         char *p, *name;
 257         int arg = 0;
 258
 259         if (!options)
 260                 return 0;
 261
 262         while ((p = strsep(&options, ",")) != NULL) {
 263                 int token;
 264                 if (!*p)
 265                         continue;
 266                 /*
 267                  * Initialize args struct so we know whether arg was
 268                  * found; some options take optional arguments.
 269                  */
 270                 args[0].to = args[0].from = NULL;
 271                 token = match_token(p, f2fs_tokens, args);
 272
 273                 switch (token) {
 274                 case Opt_gc_background:
 275                         name = match_strdup(&args[0]);
 276
 277                         if (!name)
 278                                 return -ENOMEM;
 279                         if (strlen(name) == 2 && !strncmp(name, "on", 2))
 280                                 set_opt(sbi, BG_GC);
 281                         else if (strlen(name) == 3 && !strncmp(name, "off", 3))
 282                                 clear_opt(sbi, BG_GC);
 283                         else {
 284                                 kfree(name);
 285                                 return -EINVAL;
 286                         }
 287                         kfree(name);
 288                         break;
 289                 case Opt_disable_roll_forward:
 290                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 291                         break;
 292                 case Opt_norecovery:
 293                         /* this option mounts f2fs with ro */
 294                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 295                         if (!f2fs_readonly(sb))
 296                                 return -EINVAL;
 297                         break;
 298                 case Opt_discard:
 299                         set_opt(sbi, DISCARD);
 300                         break;
 301                 case Opt_noheap:
 302                         set_opt(sbi, NOHEAP);
 303                         break;
 304 #ifdef CONFIG_F2FS_FS_XATTR
 305                 case Opt_user_xattr:
 306                         set_opt(sbi, XATTR_USER);
 307                         break;
 308                 case Opt_nouser_xattr:
 309                         clear_opt(sbi, XATTR_USER);
 310                         break;
 311                 case Opt_inline_xattr:
 312                         set_opt(sbi, INLINE_XATTR);
 313                         break;
 314 #else
 315                 case Opt_user_xattr:
 316                         f2fs_msg(sb, KERN_INFO,
 317                                 "user_xattr options not supported");
 318                         break;
 319                 case Opt_nouser_xattr:
 320                         f2fs_msg(sb, KERN_INFO,
 321                                 "nouser_xattr options not supported");
 322                         break;
 323                 case Opt_inline_xattr:
 324                         f2fs_msg(sb, KERN_INFO,
 325                                 "inline_xattr options not supported");
 326                         break;
 327 #endif
 328 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 329                 case Opt_acl:
 330                         set_opt(sbi, POSIX_ACL);
 331                         break;
 332                 case Opt_noacl:
 333                         clear_opt(sbi, POSIX_ACL);
 334                         break;
 335 #else
 336                 case Opt_acl:
 337                         f2fs_msg(sb, KERN_INFO, "acl options not supported");
 338                         break;
 339                 case Opt_noacl:
 340                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 341                         break;
 342 #endif
 343                 case Opt_active_logs:
 344                         if (args->from && match_int(args, &arg))
 345                                 return -EINVAL;
 346                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 347                                 return -EINVAL;
 348                         sbi->active_logs = arg;
 349                         break;
 350                 case Opt_disable_ext_identify:
 351                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 352                         break;
 353                 case Opt_inline_data:
 354                         set_opt(sbi, INLINE_DATA);
 355                         break;
 356                 case Opt_inline_dentry:
 357                         set_opt(sbi, INLINE_DENTRY);
 358                         break;
 359                 case Opt_flush_merge:
 360                         set_opt(sbi, FLUSH_MERGE);
 361                         break;
 362                 case Opt_nobarrier:
 363                         set_opt(sbi, NOBARRIER);
 364                         break;
 365                 case Opt_fastboot:
 366                         set_opt(sbi, FASTBOOT);
 367                         break;
 368                 default:
 369                         f2fs_msg(sb, KERN_ERR,
 370                                 "Unrecognized mount option \"%s\" or missing value",
 371                                 p);
 372                         return -EINVAL;
 373                 }
 374         }
 375         return 0;
 376 }
 377
 378 static struct inode *f2fs_alloc_inode(struct super_block *sb)
 379 {
 380         struct f2fs_inode_info *fi;
 381
 382         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
 383         if (!fi)
 384                 return NULL;
 385
 386         init_once((void *) fi);
 387
 388         /* Initialize f2fs-specific inode info */
 389         fi->vfs_inode.i_version = 1;
 390         atomic_set(&fi->dirty_pages, 0);
 391         fi->i_current_depth = 1;
 392         fi->i_advise = 0;
 393         rwlock_init(&fi->ext.ext_lock);
 394         init_rwsem(&fi->i_sem);
 395         INIT_RADIX_TREE(&fi->inmem_root, GFP_NOFS);
 396         INIT_LIST_HEAD(&fi->inmem_pages);
 397         mutex_init(&fi->inmem_lock);
 398
 399         set_inode_flag(fi, FI_NEW_INODE);
 400
 401         if (test_opt(F2FS_SB(sb), INLINE_XATTR))
 402                 set_inode_flag(fi, FI_INLINE_XATTR);
 403
 404         /* Will be used by directory only */
 405         fi->i_dir_level = F2FS_SB(sb)->dir_level;
 406
 407         return &fi->vfs_inode;
 408 }
 409
 410 static int f2fs_drop_inode(struct inode *inode)
 411 {
 412         /*
 413          * This is to avoid a deadlock condition like below.
 414          * writeback_single_inode(inode)
 415          *  - f2fs_write_data_page
 416          *    - f2fs_gc -> iput -> evict
 417          *       - inode_wait_for_writeback(inode)
 418          */
 419         if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
 420                 return 0;
 421         return generic_drop_inode(inode);
 422 }
 423
 424 /*
 425  * f2fs_dirty_inode() is called from __mark_inode_dirty()
 426  *
 427  * We should call set_dirty_inode to write the dirty inode through write_inode.
 428  */
 429 static void f2fs_dirty_inode(struct inode *inode, int flags)
 430 {
 431         set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
 432 }
 433
 434 static void f2fs_i_callback(struct rcu_head *head)
 435 {
 436         struct inode *inode = container_of(head, struct inode, i_rcu);
 437         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 438 }
 439
 440 static void f2fs_destroy_inode(struct inode *inode)
 441 {
 442         call_rcu(&inode->i_rcu, f2fs_i_callback);
 443 }
 444
 445 static void f2fs_put_super(struct super_block *sb)
 446 {
 447         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 448
 449         if (sbi->s_proc) {
 450                 remove_proc_entry("segment_info", sbi->s_proc);
 451                 remove_proc_entry(sb->s_id, f2fs_proc_root);
 452         }
 453         kobject_del(&sbi->s_kobj);
 454
 455         f2fs_destroy_stats(sbi);
 456         stop_gc_thread(sbi);
 457
 458         /*
 459          * We don't need to do checkpoint when superblock is clean.
 460          * But, the previous checkpoint was not done by umount, it needs to do
 461          * clean checkpoint again.
 462          */
 463         if (is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
 464                         !is_set_ckpt_flags(F2FS_CKPT(sbi), CP_UMOUNT_FLAG)) {
 465                 struct cp_control cpc = {
 466                         .reason = CP_UMOUNT,
 467                 };
 468                 write_checkpoint(sbi, &cpc);
 469         }
 470
 471         /*
 472          * normally superblock is clean, so we need to release this.
 473          * In addition, EIO will skip do checkpoint, we need this as well.
 474          */
 475         release_dirty_inode(sbi);
 476         release_discard_addrs(sbi);
 477
 478         iput(sbi->node_inode);
 479         iput(sbi->meta_inode);
 480
 481         /* destroy f2fs internal modules */
 482         destroy_node_manager(sbi);
 483         destroy_segment_manager(sbi);
 484
 485         kfree(sbi->ckpt);
 486         kobject_put(&sbi->s_kobj);
 487         wait_for_completion(&sbi->s_kobj_unregister);
 488
 489         sb->s_fs_info = NULL;
 490         brelse(sbi->raw_super_buf);
 491         kfree(sbi);
 492 }
 493
 494 int f2fs_sync_fs(struct super_block *sb, int sync)
 495 {
 496         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 497
 498         trace_f2fs_sync_fs(sb, sync);
 499
 500         if (sync) {
 501                 struct cp_control cpc;
 502
 503                 cpc.reason = (test_opt(sbi, FASTBOOT) ||
 504                                         is_sbi_flag_set(sbi, SBI_IS_CLOSE)) ?
 505                                                 CP_UMOUNT : CP_SYNC;
 506                 mutex_lock(&sbi->gc_mutex);
 507                 write_checkpoint(sbi, &cpc);
 508                 mutex_unlock(&sbi->gc_mutex);
 509         } else {
 510                 f2fs_balance_fs(sbi);
 511         }
 512         f2fs_trace_ios(NULL, NULL, 1);
 513
 514         return 0;
 515 }
 516
 517 static int f2fs_freeze(struct super_block *sb)
 518 {
 519         int err;
 520
 521         if (f2fs_readonly(sb))
 522                 return 0;
 523
 524         err = f2fs_sync_fs(sb, 1);
 525         return err;
 526 }
 527
 528 static int f2fs_unfreeze(struct super_block *sb)
 529 {
 530         return 0;
 531 }
 532
 533 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 534 {
 535         struct super_block *sb = dentry->d_sb;
 536         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 537         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 538         block_t total_count, user_block_count, start_count, ovp_count;
 539
 540         total_count = le64_to_cpu(sbi->raw_super->block_count);
 541         user_block_count = sbi->user_block_count;
 542         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 543         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 544         buf->f_type = F2FS_SUPER_MAGIC;
 545         buf->f_bsize = sbi->blocksize;
 546
 547         buf->f_blocks = total_count - start_count;
 548         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 549         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 550
 551         buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
 552         buf->f_ffree = buf->f_files - valid_inode_count(sbi);
 553
 554         buf->f_namelen = F2FS_NAME_LEN;
 555         buf->f_fsid.val[0] = (u32)id;
 556         buf->f_fsid.val[1] = (u32)(id >> 32);
 557
 558         return 0;
 559 }
 560
 561 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 562 {
 563         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 564
 565         if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
 566                 seq_printf(seq, ",background_gc=%s", "on");
 567         else
 568                 seq_printf(seq, ",background_gc=%s", "off");
 569         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 570                 seq_puts(seq, ",disable_roll_forward");
 571         if (test_opt(sbi, DISCARD))
 572                 seq_puts(seq, ",discard");
 573         if (test_opt(sbi, NOHEAP))
 574                 seq_puts(seq, ",no_heap_alloc");
 575 #ifdef CONFIG_F2FS_FS_XATTR
 576         if (test_opt(sbi, XATTR_USER))
 577                 seq_puts(seq, ",user_xattr");
 578         else
 579                 seq_puts(seq, ",nouser_xattr");
 580         if (test_opt(sbi, INLINE_XATTR))
 581                 seq_puts(seq, ",inline_xattr");
 582 #endif
 583 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 584         if (test_opt(sbi, POSIX_ACL))
 585                 seq_puts(seq, ",acl");
 586         else
 587                 seq_puts(seq, ",noacl");
 588 #endif
 589         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 590                 seq_puts(seq, ",disable_ext_identify");
 591         if (test_opt(sbi, INLINE_DATA))
 592                 seq_puts(seq, ",inline_data");
 593         if (test_opt(sbi, INLINE_DENTRY))
 594                 seq_puts(seq, ",inline_dentry");
 595         if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
 596                 seq_puts(seq, ",flush_merge");
 597         if (test_opt(sbi, NOBARRIER))
 598                 seq_puts(seq, ",nobarrier");
 599         if (test_opt(sbi, FASTBOOT))
 600                 seq_puts(seq, ",fastboot");
 601         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 602
 603         return 0;
 604 }
 605
 606 static int segment_info_seq_show(struct seq_file *seq, void *offset)
 607 {
 608         struct super_block *sb = seq->private;
 609         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 610         unsigned int total_segs =
 611                         le32_to_cpu(sbi->raw_super->segment_count_main);
 612         int i;
 613
 614         seq_puts(seq, "format: segment_type|valid_blocks\n"
 615                 "segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
 616
 617         for (i = 0; i < total_segs; i++) {
 618                 struct seg_entry *se = get_seg_entry(sbi, i);
 619
 620                 if ((i % 10) == 0)
 621                         seq_printf(seq, "%-5d", i);
 622                 seq_printf(seq, "%d|%-3u", se->type,
 623                                         get_valid_blocks(sbi, i, 1));
 624                 if ((i % 10) == 9 || i == (total_segs - 1))
 625                         seq_putc(seq, '\n');
 626                 else
 627                         seq_putc(seq, ' ');
 628         }
 629
 630         return 0;
 631 }
 632
 633 static int segment_info_open_fs(struct inode *inode, struct file *file)
 634 {
 635         return single_open(file, segment_info_seq_show, PDE_DATA(inode));
 636 }
 637
 638 static const struct file_operations f2fs_seq_segment_info_fops = {
 639         .owner = THIS_MODULE,
 640         .open = segment_info_open_fs,
 641         .read = seq_read,
 642         .llseek = seq_lseek,
 643         .release = single_release,
 644 };
 645
 646 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 647 {
 648         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 649         struct f2fs_mount_info org_mount_opt;
 650         int err, active_logs;
 651         bool need_restart_gc = false;
 652         bool need_stop_gc = false;
 653
 654         sync_filesystem(sb);
 655
 656         /*
 657          * Save the old mount options in case we
 658          * need to restore them.
 659          */
 660         org_mount_opt = sbi->mount_opt;
 661         active_logs = sbi->active_logs;
 662
 663         sbi->mount_opt.opt = 0;
 664         sbi->active_logs = NR_CURSEG_TYPE;
 665
 666         /* parse mount options */
 667         err = parse_options(sb, data);
 668         if (err)
 669                 goto restore_opts;
 670
 671         /*
 672          * Previous and new state of filesystem is RO,
 673          * so skip checking GC and FLUSH_MERGE conditions.
 674          */
 675         if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
 676                 goto skip;
 677
 678         /*
 679          * We stop the GC thread if FS is mounted as RO
 680          * or if background_gc = off is passed in mount
 681          * option. Also sync the filesystem.
 682          */
 683         if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
 684                 if (sbi->gc_thread) {
 685                         stop_gc_thread(sbi);
 686                         f2fs_sync_fs(sb, 1);
 687                         need_restart_gc = true;
 688                 }
 689         } else if (!sbi->gc_thread) {
 690                 err = start_gc_thread(sbi);
 691                 if (err)
 692                         goto restore_opts;
 693                 need_stop_gc = true;
 694         }
 695
 696         /*
 697          * We stop issue flush thread if FS is mounted as RO
 698          * or if flush_merge is not passed in mount option.
 699          */
 700         if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
 701                 destroy_flush_cmd_control(sbi);
 702         } else if (!SM_I(sbi)->cmd_control_info) {
 703                 err = create_flush_cmd_control(sbi);
 704                 if (err)
 705                         goto restore_gc;
 706         }
 707 skip:
 708         /* Update the POSIXACL Flag */
 709          sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 710                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 711         return 0;
 712 restore_gc:
 713         if (need_restart_gc) {
 714                 if (start_gc_thread(sbi))
 715                         f2fs_msg(sbi->sb, KERN_WARNING,
 716                                 "background gc thread has stopped");
 717         } else if (need_stop_gc) {
 718                 stop_gc_thread(sbi);
 719         }
 720 restore_opts:
 721         sbi->mount_opt = org_mount_opt;
 722         sbi->active_logs = active_logs;
 723         return err;
 724 }
 725
 726 static struct super_operations f2fs_sops = {
 727         .alloc_inode    = f2fs_alloc_inode,
 728         .drop_inode     = f2fs_drop_inode,
 729         .destroy_inode  = f2fs_destroy_inode,
 730         .write_inode    = f2fs_write_inode,
 731         .dirty_inode    = f2fs_dirty_inode,
 732         .show_options   = f2fs_show_options,
 733         .evict_inode    = f2fs_evict_inode,
 734         .put_super      = f2fs_put_super,
 735         .sync_fs        = f2fs_sync_fs,
 736         .freeze_fs      = f2fs_freeze,
 737         .unfreeze_fs    = f2fs_unfreeze,
 738         .statfs         = f2fs_statfs,
 739         .remount_fs     = f2fs_remount,
 740 };
 741
 742 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 743                 u64 ino, u32 generation)
 744 {
 745         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 746         struct inode *inode;
 747
 748         if (check_nid_range(sbi, ino))
 749                 return ERR_PTR(-ESTALE);
 750
 751         /*
 752          * f2fs_iget isn't quite right if the inode is currently unallocated!
 753          * However f2fs_iget currently does appropriate checks to handle stale
 754          * inodes so everything is OK.
 755          */
 756         inode = f2fs_iget(sb, ino);
 757         if (IS_ERR(inode))
 758                 return ERR_CAST(inode);
 759         if (unlikely(generation && inode->i_generation != generation)) {
 760                 /* we didn't find the right inode.. */
 761                 iput(inode);
 762                 return ERR_PTR(-ESTALE);
 763         }
 764         return inode;
 765 }
 766
 767 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 768                 int fh_len, int fh_type)
 769 {
 770         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 771                                     f2fs_nfs_get_inode);
 772 }
 773
 774 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 775                 int fh_len, int fh_type)
 776 {
 777         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 778                                     f2fs_nfs_get_inode);
 779 }
 780
 781 static const struct export_operations f2fs_export_ops = {
 782         .fh_to_dentry = f2fs_fh_to_dentry,
 783         .fh_to_parent = f2fs_fh_to_parent,
 784         .get_parent = f2fs_get_parent,
 785 };
 786
 787 static loff_t max_file_size(unsigned bits)
 788 {
 789         loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
 790         loff_t leaf_count = ADDRS_PER_BLOCK;
 791
 792         /* two direct node blocks */
 793         result += (leaf_count * 2);
 794
 795         /* two indirect node blocks */
 796         leaf_count *= NIDS_PER_BLOCK;
 797         result += (leaf_count * 2);
 798
 799         /* one double indirect node block */
 800         leaf_count *= NIDS_PER_BLOCK;
 801         result += leaf_count;
 802
 803         result <<= bits;
 804         return result;
 805 }
 806
 807 static int sanity_check_raw_super(struct super_block *sb,
 808                         struct f2fs_super_block *raw_super)
 809 {
 810         unsigned int blocksize;
 811
 812         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 813                 f2fs_msg(sb, KERN_INFO,
 814                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 815                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 816                 return 1;
 817         }
 818
 819         /* Currently, support only 4KB page cache size */
 820         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 821                 f2fs_msg(sb, KERN_INFO,
 822                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 823                         PAGE_CACHE_SIZE);
 824                 return 1;
 825         }
 826
 827         /* Currently, support only 4KB block size */
 828         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 829         if (blocksize != F2FS_BLKSIZE) {
 830                 f2fs_msg(sb, KERN_INFO,
 831                         "Invalid blocksize (%u), supports only 4KB\n",
 832                         blocksize);
 833                 return 1;
 834         }
 835
 836         /* Currently, support 512/1024/2048/4096 bytes sector size */
 837         if (le32_to_cpu(raw_super->log_sectorsize) >
 838                                 F2FS_MAX_LOG_SECTOR_SIZE ||
 839                 le32_to_cpu(raw_super->log_sectorsize) <
 840                                 F2FS_MIN_LOG_SECTOR_SIZE) {
 841                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize (%u)",
 842                         le32_to_cpu(raw_super->log_sectorsize));
 843                 return 1;
 844         }
 845         if (le32_to_cpu(raw_super->log_sectors_per_block) +
 846                 le32_to_cpu(raw_super->log_sectorsize) !=
 847                         F2FS_MAX_LOG_SECTOR_SIZE) {
 848                 f2fs_msg(sb, KERN_INFO,
 849                         "Invalid log sectors per block(%u) log sectorsize(%u)",
 850                         le32_to_cpu(raw_super->log_sectors_per_block),
 851                         le32_to_cpu(raw_super->log_sectorsize));
 852                 return 1;
 853         }
 854         return 0;
 855 }
 856
 857 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 858 {
 859         unsigned int total, fsmeta;
 860         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 861         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 862
 863         total = le32_to_cpu(raw_super->segment_count);
 864         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 865         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 866         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 867         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 868         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 869
 870         if (unlikely(fsmeta >= total))
 871                 return 1;
 872
 873         if (unlikely(f2fs_cp_error(sbi))) {
 874                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 875                 return 1;
 876         }
 877         return 0;
 878 }
 879
 880 static void init_sb_info(struct f2fs_sb_info *sbi)
 881 {
 882         struct f2fs_super_block *raw_super = sbi->raw_super;
 883         int i;
 884
 885         sbi->log_sectors_per_block =
 886                 le32_to_cpu(raw_super->log_sectors_per_block);
 887         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 888         sbi->blocksize = 1 << sbi->log_blocksize;
 889         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 890         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 891         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 892         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 893         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 894         sbi->total_node_count =
 895                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 896                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 897         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 898         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 899         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 900         sbi->cur_victim_sec = NULL_SECNO;
 901         sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
 902
 903         for (i = 0; i < NR_COUNT_TYPE; i++)
 904                 atomic_set(&sbi->nr_pages[i], 0);
 905
 906         sbi->dir_level = DEF_DIR_LEVEL;
 907         clear_sbi_flag(sbi, SBI_NEED_FSCK);
 908 }
 909
 910 /*
 911  * Read f2fs raw super block.
 912  * Because we have two copies of super block, so read the first one at first,
 913  * if the first one is invalid, move to read the second one.
 914  */
 915 static int read_raw_super_block(struct super_block *sb,
 916                         struct f2fs_super_block **raw_super,
 917                         struct buffer_head **raw_super_buf)
 918 {
 919         int block = 0;
 920
 921 retry:
 922         *raw_super_buf = sb_bread(sb, block);
 923         if (!*raw_super_buf) {
 924                 f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
 925                                 block + 1);
 926                 if (block == 0) {
 927                         block++;
 928                         goto retry;
 929                 } else {
 930                         return -EIO;
 931                 }
 932         }
 933
 934         *raw_super = (struct f2fs_super_block *)
 935                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 936
 937         /* sanity checking of raw super */
 938         if (sanity_check_raw_super(sb, *raw_super)) {
 939                 brelse(*raw_super_buf);
 940                 f2fs_msg(sb, KERN_ERR,
 941                         "Can't find valid F2FS filesystem in %dth superblock",
 942                                                                 block + 1);
 943                 if (block == 0) {
 944                         block++;
 945                         goto retry;
 946                 } else {
 947                         return -EINVAL;
 948                 }
 949         }
 950
 951         return 0;
 952 }
 953
 954 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 955 {
 956         struct f2fs_sb_info *sbi;
 957         struct f2fs_super_block *raw_super = NULL;
 958         struct buffer_head *raw_super_buf;
 959         struct inode *root;
 960         long err = -EINVAL;
 961         bool retry = true;
 962         char *options = NULL;
 963         int i;
 964
 965 try_onemore:
 966         /* allocate memory for f2fs-specific super block info */
 967         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 968         if (!sbi)
 969                 return -ENOMEM;
 970
 971         /* set a block size */
 972         if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
 973                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 974                 goto free_sbi;
 975         }
 976
 977         err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
 978         if (err)
 979                 goto free_sbi;
 980
 981         sb->s_fs_info = sbi;
 982         /* init some FS parameters */
 983         sbi->active_logs = NR_CURSEG_TYPE;
 984
 985         set_opt(sbi, BG_GC);
 986
 987 #ifdef CONFIG_F2FS_FS_XATTR
 988         set_opt(sbi, XATTR_USER);
 989 #endif
 990 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 991         set_opt(sbi, POSIX_ACL);
 992 #endif
 993         /* parse mount options */
 994         options = kstrdup((const char *)data, GFP_KERNEL);
 995         if (data && !options) {
 996                 err = -ENOMEM;
 997                 goto free_sb_buf;
 998         }
 999
1000         err = parse_options(sb, options);
1001         if (err)
1002                 goto free_options;
1003
1004         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
1005         sb->s_max_links = F2FS_LINK_MAX;
1006         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1007
1008         sb->s_op = &f2fs_sops;
1009         sb->s_xattr = f2fs_xattr_handlers;
1010         sb->s_export_op = &f2fs_export_ops;
1011         sb->s_magic = F2FS_SUPER_MAGIC;
1012         sb->s_time_gran = 1;
1013         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1014                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
1015         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
1016
1017         /* init f2fs-specific super block info */
1018         sbi->sb = sb;
1019         sbi->raw_super = raw_super;
1020         sbi->raw_super_buf = raw_super_buf;
1021         mutex_init(&sbi->gc_mutex);
1022         mutex_init(&sbi->writepages);
1023         mutex_init(&sbi->cp_mutex);
1024         init_rwsem(&sbi->node_write);
1025         clear_sbi_flag(sbi, SBI_POR_DOING);
1026         spin_lock_init(&sbi->stat_lock);
1027
1028         init_rwsem(&sbi->read_io.io_rwsem);
1029         sbi->read_io.sbi = sbi;
1030         sbi->read_io.bio = NULL;
1031         for (i = 0; i < NR_PAGE_TYPE; i++) {
1032                 init_rwsem(&sbi->write_io[i].io_rwsem);
1033                 sbi->write_io[i].sbi = sbi;
1034                 sbi->write_io[i].bio = NULL;
1035         }
1036
1037         init_rwsem(&sbi->cp_rwsem);
1038         init_waitqueue_head(&sbi->cp_wait);
1039         init_sb_info(sbi);
1040
1041         /* get an inode for meta space */
1042         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
1043         if (IS_ERR(sbi->meta_inode)) {
1044                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
1045                 err = PTR_ERR(sbi->meta_inode);
1046                 goto free_options;
1047         }
1048
1049         err = get_valid_checkpoint(sbi);
1050         if (err) {
1051                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
1052                 goto free_meta_inode;
1053         }
1054
1055         /* sanity checking of checkpoint */
1056         err = -EINVAL;
1057         if (sanity_check_ckpt(sbi)) {
1058                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
1059                 goto free_cp;
1060         }
1061
1062         sbi->total_valid_node_count =
1063                                 le32_to_cpu(sbi->ckpt->valid_node_count);
1064         sbi->total_valid_inode_count =
1065                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
1066         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1067         sbi->total_valid_block_count =
1068                                 le64_to_cpu(sbi->ckpt->valid_block_count);
1069         sbi->last_valid_block_count = sbi->total_valid_block_count;
1070         sbi->alloc_valid_block_count = 0;
1071         INIT_LIST_HEAD(&sbi->dir_inode_list);
1072         spin_lock_init(&sbi->dir_inode_lock);
1073
1074         init_ino_entry_info(sbi);
1075
1076         /* setup f2fs internal modules */
1077         err = build_segment_manager(sbi);
1078         if (err) {
1079                 f2fs_msg(sb, KERN_ERR,
1080                         "Failed to initialize F2FS segment manager");
1081                 goto free_sm;
1082         }
1083         err = build_node_manager(sbi);
1084         if (err) {
1085                 f2fs_msg(sb, KERN_ERR,
1086                         "Failed to initialize F2FS node manager");
1087                 goto free_nm;
1088         }
1089
1090         build_gc_manager(sbi);
1091
1092         /* get an inode for node space */
1093         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1094         if (IS_ERR(sbi->node_inode)) {
1095                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1096                 err = PTR_ERR(sbi->node_inode);
1097                 goto free_nm;
1098         }
1099
1100         /* if there are nt orphan nodes free them */
1101         recover_orphan_inodes(sbi);
1102
1103         /* read root inode and dentry */
1104         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1105         if (IS_ERR(root)) {
1106                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1107                 err = PTR_ERR(root);
1108                 goto free_node_inode;
1109         }
1110         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1111                 iput(root);
1112                 err = -EINVAL;
1113                 goto free_node_inode;
1114         }
1115
1116         sb->s_root = d_make_root(root); /* allocate root dentry */
1117         if (!sb->s_root) {
1118                 err = -ENOMEM;
1119                 goto free_root_inode;
1120         }
1121
1122         err = f2fs_build_stats(sbi);
1123         if (err)
1124                 goto free_root_inode;
1125
1126         if (f2fs_proc_root)
1127                 sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1128
1129         if (sbi->s_proc)
1130                 proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1131                                  &f2fs_seq_segment_info_fops, sb);
1132
1133         if (test_opt(sbi, DISCARD)) {
1134                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
1135                 if (!blk_queue_discard(q))
1136                         f2fs_msg(sb, KERN_WARNING,
1137                                         "mounting with \"discard\" option, but "
1138                                         "the device does not support discard");
1139         }
1140
1141         sbi->s_kobj.kset = f2fs_kset;
1142         init_completion(&sbi->s_kobj_unregister);
1143         err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1144                                                         "%s", sb->s_id);
1145         if (err)
1146                 goto free_proc;
1147
1148         if (!retry)
1149                 set_sbi_flag(sbi, SBI_NEED_FSCK);
1150
1151         /* recover fsynced data */
1152         if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1153                 err = recover_fsync_data(sbi);
1154                 if (err) {
1155                         f2fs_msg(sb, KERN_ERR,
1156                                 "Cannot recover all fsync data errno=%ld", err);
1157                         goto free_kobj;
1158                 }
1159         }
1160
1161         /*
1162          * If filesystem is not mounted as read-only then
1163          * do start the gc_thread.
1164          */
1165         if (test_opt(sbi, BG_GC) && !f2fs_readonly(sb)) {
1166                 /* After POR, we can run background GC thread.*/
1167                 err = start_gc_thread(sbi);
1168                 if (err)
1169                         goto free_kobj;
1170         }
1171         kfree(options);
1172         return 0;
1173
1174 free_kobj:
1175         kobject_del(&sbi->s_kobj);
1176 free_proc:
1177         if (sbi->s_proc) {
1178                 remove_proc_entry("segment_info", sbi->s_proc);
1179                 remove_proc_entry(sb->s_id, f2fs_proc_root);
1180         }
1181         f2fs_destroy_stats(sbi);
1182 free_root_inode:
1183         dput(sb->s_root);
1184         sb->s_root = NULL;
1185 free_node_inode:
1186         iput(sbi->node_inode);
1187 free_nm:
1188         destroy_node_manager(sbi);
1189 free_sm:
1190         destroy_segment_manager(sbi);
1191 free_cp:
1192         kfree(sbi->ckpt);
1193 free_meta_inode:
1194         make_bad_inode(sbi->meta_inode);
1195         iput(sbi->meta_inode);
1196 free_options:
1197         kfree(options);
1198 free_sb_buf:
1199         brelse(raw_super_buf);
1200 free_sbi:
1201         kfree(sbi);
1202
1203         /* give only one another chance */
1204         if (retry) {
1205                 retry = 0;
1206                 shrink_dcache_sb(sb);
1207                 goto try_onemore;
1208         }
1209         return err;
1210 }
1211
1212 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1213                         const char *dev_name, void *data)
1214 {
1215         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1216 }
1217
1218 static void kill_f2fs_super(struct super_block *sb)
1219 {
1220         if (sb->s_root)
1221                 set_sbi_flag(F2FS_SB(sb), SBI_IS_CLOSE);
1222         kill_block_super(sb);
1223 }
1224
1225 static struct file_system_type f2fs_fs_type = {
1226         .owner          = THIS_MODULE,
1227         .name           = "f2fs",
1228         .mount          = f2fs_mount,
1229         .kill_sb        = kill_f2fs_super,
1230         .fs_flags       = FS_REQUIRES_DEV,
1231 };
1232 MODULE_ALIAS_FS("f2fs");
1233
1234 static int __init init_inodecache(void)
1235 {
1236         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1237                         sizeof(struct f2fs_inode_info));
1238         if (!f2fs_inode_cachep)
1239                 return -ENOMEM;
1240         return 0;
1241 }
1242
1243 static void destroy_inodecache(void)
1244 {
1245         /*
1246          * Make sure all delayed rcu free inodes are flushed before we
1247          * destroy cache.
1248          */
1249         rcu_barrier();
1250         kmem_cache_destroy(f2fs_inode_cachep);
1251 }
1252
1253 static int __init init_f2fs_fs(void)
1254 {
1255         int err;
1256
1257         f2fs_build_trace_ios();
1258
1259         err = init_inodecache();
1260         if (err)
1261                 goto fail;
1262         err = create_node_manager_caches();
1263         if (err)
1264                 goto free_inodecache;
1265         err = create_segment_manager_caches();
1266         if (err)
1267                 goto free_node_manager_caches;
1268         err = create_checkpoint_caches();
1269         if (err)
1270                 goto free_segment_manager_caches;
1271         f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1272         if (!f2fs_kset) {
1273                 err = -ENOMEM;
1274                 goto free_checkpoint_caches;
1275         }
1276         err = register_filesystem(&f2fs_fs_type);
1277         if (err)
1278                 goto free_kset;
1279         f2fs_create_root_stats();
1280         f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1281         return 0;
1282
1283 free_kset:
1284         kset_unregister(f2fs_kset);
1285 free_checkpoint_caches:
1286         destroy_checkpoint_caches();
1287 free_segment_manager_caches:
1288         destroy_segment_manager_caches();
1289 free_node_manager_caches:
1290         destroy_node_manager_caches();
1291 free_inodecache:
1292         destroy_inodecache();
1293 fail:
1294         return err;
1295 }
1296
1297 static void __exit exit_f2fs_fs(void)
1298 {
1299         remove_proc_entry("fs/f2fs", NULL);
1300         f2fs_destroy_root_stats();
1301         unregister_filesystem(&f2fs_fs_type);
1302         destroy_checkpoint_caches();
1303         destroy_segment_manager_caches();
1304         destroy_node_manager_caches();
1305         destroy_inodecache();
1306         kset_unregister(f2fs_kset);
1307         f2fs_destroy_trace_ios();
1308 }
1309
1310 module_init(init_f2fs_fs)
1311 module_exit(exit_f2fs_fs)
1312
1313 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1314 MODULE_DESCRIPTION("Flash Friendly File System");
1315 MODULE_LICENSE("GPL");