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
  34 #define CREATE_TRACE_POINTS
  35 #include <trace/events/f2fs.h>
  36
  37 static struct proc_dir_entry *f2fs_proc_root;
  38 static struct kmem_cache *f2fs_inode_cachep;
  39 static struct kset *f2fs_kset;
  40
  41 enum {
  42         Opt_gc_background,
  43         Opt_disable_roll_forward,
  44         Opt_discard,
  45         Opt_noheap,
  46         Opt_nouser_xattr,
  47         Opt_noacl,
  48         Opt_active_logs,
  49         Opt_disable_ext_identify,
  50         Opt_inline_xattr,
  51         Opt_err,
  52 };
  53
  54 static match_table_t f2fs_tokens = {
  55         {Opt_gc_background, "background_gc=%s"},
  56         {Opt_disable_roll_forward, "disable_roll_forward"},
  57         {Opt_discard, "discard"},
  58         {Opt_noheap, "no_heap"},
  59         {Opt_nouser_xattr, "nouser_xattr"},
  60         {Opt_noacl, "noacl"},
  61         {Opt_active_logs, "active_logs=%u"},
  62         {Opt_disable_ext_identify, "disable_ext_identify"},
  63         {Opt_inline_xattr, "inline_xattr"},
  64         {Opt_err, NULL},
  65 };
  66
  67 /* Sysfs support for f2fs */
  68 struct f2fs_attr {
  69         struct attribute attr;
  70         ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
  71         ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
  72                          const char *, size_t);
  73         int offset;
  74 };
  75
  76 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
  77                         struct f2fs_sb_info *sbi, char *buf)
  78 {
  79         struct f2fs_gc_kthread *gc_kth = sbi->gc_thread;
  80         unsigned int *ui;
  81
  82         if (!gc_kth)
  83                 return -EINVAL;
  84
  85         ui = (unsigned int *)(((char *)gc_kth) + a->offset);
  86
  87         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
  88 }
  89
  90 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
  91                         struct f2fs_sb_info *sbi,
  92                         const char *buf, size_t count)
  93 {
  94         struct f2fs_gc_kthread *gc_kth = sbi->gc_thread;
  95         unsigned long t;
  96         unsigned int *ui;
  97         ssize_t ret;
  98
  99         if (!gc_kth)
 100                 return -EINVAL;
 101
 102         ui = (unsigned int *)(((char *)gc_kth) + a->offset);
 103
 104         ret = kstrtoul(skip_spaces(buf), 0, &t);
 105         if (ret < 0)
 106                 return ret;
 107         *ui = t;
 108         return count;
 109 }
 110
 111 static ssize_t f2fs_attr_show(struct kobject *kobj,
 112                                 struct attribute *attr, char *buf)
 113 {
 114         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 115                                                                 s_kobj);
 116         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 117
 118         return a->show ? a->show(a, sbi, buf) : 0;
 119 }
 120
 121 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
 122                                                 const char *buf, size_t len)
 123 {
 124         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 125                                                                         s_kobj);
 126         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 127
 128         return a->store ? a->store(a, sbi, buf, len) : 0;
 129 }
 130
 131 static void f2fs_sb_release(struct kobject *kobj)
 132 {
 133         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 134                                                                 s_kobj);
 135         complete(&sbi->s_kobj_unregister);
 136 }
 137
 138 #define F2FS_ATTR_OFFSET(_name, _mode, _show, _store, _elname) \
 139 static struct f2fs_attr f2fs_attr_##_name = {                   \
 140         .attr = {.name = __stringify(_name), .mode = _mode },   \
 141         .show   = _show,                                        \
 142         .store  = _store,                                       \
 143         .offset = offsetof(struct f2fs_gc_kthread, _elname),    \
 144 }
 145
 146 #define F2FS_RW_ATTR(name, elname)      \
 147         F2FS_ATTR_OFFSET(name, 0644, f2fs_sbi_show, f2fs_sbi_store, elname)
 148
 149 F2FS_RW_ATTR(gc_min_sleep_time, min_sleep_time);
 150 F2FS_RW_ATTR(gc_max_sleep_time, max_sleep_time);
 151 F2FS_RW_ATTR(gc_no_gc_sleep_time, no_gc_sleep_time);
 152 F2FS_RW_ATTR(gc_idle, gc_idle);
 153
 154 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 155 static struct attribute *f2fs_attrs[] = {
 156         ATTR_LIST(gc_min_sleep_time),
 157         ATTR_LIST(gc_max_sleep_time),
 158         ATTR_LIST(gc_no_gc_sleep_time),
 159         ATTR_LIST(gc_idle),
 160         NULL,
 161 };
 162
 163 static const struct sysfs_ops f2fs_attr_ops = {
 164         .show   = f2fs_attr_show,
 165         .store  = f2fs_attr_store,
 166 };
 167
 168 static struct kobj_type f2fs_ktype = {
 169         .default_attrs  = f2fs_attrs,
 170         .sysfs_ops      = &f2fs_attr_ops,
 171         .release        = f2fs_sb_release,
 172 };
 173
 174 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
 175 {
 176         struct va_format vaf;
 177         va_list args;
 178
 179         va_start(args, fmt);
 180         vaf.fmt = fmt;
 181         vaf.va = &args;
 182         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
 183         va_end(args);
 184 }
 185
 186 static void init_once(void *foo)
 187 {
 188         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
 189
 190         inode_init_once(&fi->vfs_inode);
 191 }
 192
 193 static int parse_options(struct super_block *sb, char *options)
 194 {
 195         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 196         substring_t args[MAX_OPT_ARGS];
 197         char *p, *name;
 198         int arg = 0;
 199
 200         if (!options)
 201                 return 0;
 202
 203         while ((p = strsep(&options, ",")) != NULL) {
 204                 int token;
 205                 if (!*p)
 206                         continue;
 207                 /*
 208                  * Initialize args struct so we know whether arg was
 209                  * found; some options take optional arguments.
 210                  */
 211                 args[0].to = args[0].from = NULL;
 212                 token = match_token(p, f2fs_tokens, args);
 213
 214                 switch (token) {
 215                 case Opt_gc_background:
 216                         name = match_strdup(&args[0]);
 217
 218                         if (!name)
 219                                 return -ENOMEM;
 220                         if (!strncmp(name, "on", 2))
 221                                 set_opt(sbi, BG_GC);
 222                         else if (!strncmp(name, "off", 3))
 223                                 clear_opt(sbi, BG_GC);
 224                         else {
 225                                 kfree(name);
 226                                 return -EINVAL;
 227                         }
 228                         kfree(name);
 229                         break;
 230                 case Opt_disable_roll_forward:
 231                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 232                         break;
 233                 case Opt_discard:
 234                         set_opt(sbi, DISCARD);
 235                         break;
 236                 case Opt_noheap:
 237                         set_opt(sbi, NOHEAP);
 238                         break;
 239 #ifdef CONFIG_F2FS_FS_XATTR
 240                 case Opt_nouser_xattr:
 241                         clear_opt(sbi, XATTR_USER);
 242                         break;
 243                 case Opt_inline_xattr:
 244                         set_opt(sbi, INLINE_XATTR);
 245                         break;
 246 #else
 247                 case Opt_nouser_xattr:
 248                         f2fs_msg(sb, KERN_INFO,
 249                                 "nouser_xattr options not supported");
 250                         break;
 251                 case Opt_inline_xattr:
 252                         f2fs_msg(sb, KERN_INFO,
 253                                 "inline_xattr options not supported");
 254                         break;
 255 #endif
 256 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 257                 case Opt_noacl:
 258                         clear_opt(sbi, POSIX_ACL);
 259                         break;
 260 #else
 261                 case Opt_noacl:
 262                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 263                         break;
 264 #endif
 265                 case Opt_active_logs:
 266                         if (args->from && match_int(args, &arg))
 267                                 return -EINVAL;
 268                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 269                                 return -EINVAL;
 270                         sbi->active_logs = arg;
 271                         break;
 272                 case Opt_disable_ext_identify:
 273                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 274                         break;
 275                 default:
 276                         f2fs_msg(sb, KERN_ERR,
 277                                 "Unrecognized mount option \"%s\" or missing value",
 278                                 p);
 279                         return -EINVAL;
 280                 }
 281         }
 282         return 0;
 283 }
 284
 285 static struct inode *f2fs_alloc_inode(struct super_block *sb)
 286 {
 287         struct f2fs_inode_info *fi;
 288
 289         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_NOFS | __GFP_ZERO);
 290         if (!fi)
 291                 return NULL;
 292
 293         init_once((void *) fi);
 294
 295         /* Initialize f2fs-specific inode info */
 296         fi->vfs_inode.i_version = 1;
 297         atomic_set(&fi->dirty_dents, 0);
 298         fi->i_current_depth = 1;
 299         fi->i_advise = 0;
 300         rwlock_init(&fi->ext.ext_lock);
 301
 302         set_inode_flag(fi, FI_NEW_INODE);
 303
 304         if (test_opt(F2FS_SB(sb), INLINE_XATTR))
 305                 set_inode_flag(fi, FI_INLINE_XATTR);
 306
 307         return &fi->vfs_inode;
 308 }
 309
 310 static int f2fs_drop_inode(struct inode *inode)
 311 {
 312         /*
 313          * This is to avoid a deadlock condition like below.
 314          * writeback_single_inode(inode)
 315          *  - f2fs_write_data_page
 316          *    - f2fs_gc -> iput -> evict
 317          *       - inode_wait_for_writeback(inode)
 318          */
 319         if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
 320                 return 0;
 321         return generic_drop_inode(inode);
 322 }
 323
 324 /*
 325  * f2fs_dirty_inode() is called from __mark_inode_dirty()
 326  *
 327  * We should call set_dirty_inode to write the dirty inode through write_inode.
 328  */
 329 static void f2fs_dirty_inode(struct inode *inode, int flags)
 330 {
 331         set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
 332 }
 333
 334 static void f2fs_i_callback(struct rcu_head *head)
 335 {
 336         struct inode *inode = container_of(head, struct inode, i_rcu);
 337         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 338 }
 339
 340 static void f2fs_destroy_inode(struct inode *inode)
 341 {
 342         call_rcu(&inode->i_rcu, f2fs_i_callback);
 343 }
 344
 345 static void f2fs_put_super(struct super_block *sb)
 346 {
 347         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 348
 349         if (sbi->s_proc) {
 350                 remove_proc_entry("segment_info", sbi->s_proc);
 351                 remove_proc_entry(sb->s_id, f2fs_proc_root);
 352         }
 353         kobject_del(&sbi->s_kobj);
 354
 355         f2fs_destroy_stats(sbi);
 356         stop_gc_thread(sbi);
 357
 358         write_checkpoint(sbi, true);
 359
 360         iput(sbi->node_inode);
 361         iput(sbi->meta_inode);
 362
 363         /* destroy f2fs internal modules */
 364         destroy_node_manager(sbi);
 365         destroy_segment_manager(sbi);
 366
 367         kfree(sbi->ckpt);
 368         kobject_put(&sbi->s_kobj);
 369         wait_for_completion(&sbi->s_kobj_unregister);
 370
 371         sb->s_fs_info = NULL;
 372         brelse(sbi->raw_super_buf);
 373         kfree(sbi);
 374 }
 375
 376 int f2fs_sync_fs(struct super_block *sb, int sync)
 377 {
 378         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 379
 380         trace_f2fs_sync_fs(sb, sync);
 381
 382         if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
 383                 return 0;
 384
 385         if (sync) {
 386                 mutex_lock(&sbi->gc_mutex);
 387                 write_checkpoint(sbi, false);
 388                 mutex_unlock(&sbi->gc_mutex);
 389         } else {
 390                 f2fs_balance_fs(sbi);
 391         }
 392
 393         return 0;
 394 }
 395
 396 static int f2fs_freeze(struct super_block *sb)
 397 {
 398         int err;
 399
 400         if (f2fs_readonly(sb))
 401                 return 0;
 402
 403         err = f2fs_sync_fs(sb, 1);
 404         return err;
 405 }
 406
 407 static int f2fs_unfreeze(struct super_block *sb)
 408 {
 409         return 0;
 410 }
 411
 412 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 413 {
 414         struct super_block *sb = dentry->d_sb;
 415         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 416         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 417         block_t total_count, user_block_count, start_count, ovp_count;
 418
 419         total_count = le64_to_cpu(sbi->raw_super->block_count);
 420         user_block_count = sbi->user_block_count;
 421         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 422         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 423         buf->f_type = F2FS_SUPER_MAGIC;
 424         buf->f_bsize = sbi->blocksize;
 425
 426         buf->f_blocks = total_count - start_count;
 427         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 428         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 429
 430         buf->f_files = sbi->total_node_count;
 431         buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
 432
 433         buf->f_namelen = F2FS_NAME_LEN;
 434         buf->f_fsid.val[0] = (u32)id;
 435         buf->f_fsid.val[1] = (u32)(id >> 32);
 436
 437         return 0;
 438 }
 439
 440 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 441 {
 442         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 443
 444         if (!(root->d_sb->s_flags & MS_RDONLY) && test_opt(sbi, BG_GC))
 445                 seq_printf(seq, ",background_gc=%s", "on");
 446         else
 447                 seq_printf(seq, ",background_gc=%s", "off");
 448         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 449                 seq_puts(seq, ",disable_roll_forward");
 450         if (test_opt(sbi, DISCARD))
 451                 seq_puts(seq, ",discard");
 452         if (test_opt(sbi, NOHEAP))
 453                 seq_puts(seq, ",no_heap_alloc");
 454 #ifdef CONFIG_F2FS_FS_XATTR
 455         if (test_opt(sbi, XATTR_USER))
 456                 seq_puts(seq, ",user_xattr");
 457         else
 458                 seq_puts(seq, ",nouser_xattr");
 459         if (test_opt(sbi, INLINE_XATTR))
 460                 seq_puts(seq, ",inline_xattr");
 461 #endif
 462 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 463         if (test_opt(sbi, POSIX_ACL))
 464                 seq_puts(seq, ",acl");
 465         else
 466                 seq_puts(seq, ",noacl");
 467 #endif
 468         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 469                 seq_puts(seq, ",disable_ext_identify");
 470
 471         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 472
 473         return 0;
 474 }
 475
 476 static int segment_info_seq_show(struct seq_file *seq, void *offset)
 477 {
 478         struct super_block *sb = seq->private;
 479         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 480         unsigned int total_segs = le32_to_cpu(sbi->raw_super->segment_count_main);
 481         int i;
 482
 483         for (i = 0; i < total_segs; i++) {
 484                 seq_printf(seq, "%u", get_valid_blocks(sbi, i, 1));
 485                 if (i != 0 && (i % 10) == 0)
 486                         seq_puts(seq, "\n");
 487                 else
 488                         seq_puts(seq, " ");
 489         }
 490         return 0;
 491 }
 492
 493 static int segment_info_open_fs(struct inode *inode, struct file *file)
 494 {
 495         return single_open(file, segment_info_seq_show, PDE_DATA(inode));
 496 }
 497
 498 static const struct file_operations f2fs_seq_segment_info_fops = {
 499         .owner = THIS_MODULE,
 500         .open = segment_info_open_fs,
 501         .read = seq_read,
 502         .llseek = seq_lseek,
 503         .release = single_release,
 504 };
 505
 506 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 507 {
 508         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 509         struct f2fs_mount_info org_mount_opt;
 510         int err, active_logs;
 511
 512         /*
 513          * Save the old mount options in case we
 514          * need to restore them.
 515          */
 516         org_mount_opt = sbi->mount_opt;
 517         active_logs = sbi->active_logs;
 518
 519         /* parse mount options */
 520         err = parse_options(sb, data);
 521         if (err)
 522                 goto restore_opts;
 523
 524         /*
 525          * Previous and new state of filesystem is RO,
 526          * so no point in checking GC conditions.
 527          */
 528         if ((sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
 529                 goto skip;
 530
 531         /*
 532          * We stop the GC thread if FS is mounted as RO
 533          * or if background_gc = off is passed in mount
 534          * option. Also sync the filesystem.
 535          */
 536         if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
 537                 if (sbi->gc_thread) {
 538                         stop_gc_thread(sbi);
 539                         f2fs_sync_fs(sb, 1);
 540                 }
 541         } else if (test_opt(sbi, BG_GC) && !sbi->gc_thread) {
 542                 err = start_gc_thread(sbi);
 543                 if (err)
 544                         goto restore_opts;
 545         }
 546 skip:
 547         /* Update the POSIXACL Flag */
 548          sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 549                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 550         return 0;
 551
 552 restore_opts:
 553         sbi->mount_opt = org_mount_opt;
 554         sbi->active_logs = active_logs;
 555         return err;
 556 }
 557
 558 static struct super_operations f2fs_sops = {
 559         .alloc_inode    = f2fs_alloc_inode,
 560         .drop_inode     = f2fs_drop_inode,
 561         .destroy_inode  = f2fs_destroy_inode,
 562         .write_inode    = f2fs_write_inode,
 563         .dirty_inode    = f2fs_dirty_inode,
 564         .show_options   = f2fs_show_options,
 565         .evict_inode    = f2fs_evict_inode,
 566         .put_super      = f2fs_put_super,
 567         .sync_fs        = f2fs_sync_fs,
 568         .freeze_fs      = f2fs_freeze,
 569         .unfreeze_fs    = f2fs_unfreeze,
 570         .statfs         = f2fs_statfs,
 571         .remount_fs     = f2fs_remount,
 572 };
 573
 574 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 575                 u64 ino, u32 generation)
 576 {
 577         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 578         struct inode *inode;
 579
 580         if (ino < F2FS_ROOT_INO(sbi))
 581                 return ERR_PTR(-ESTALE);
 582
 583         /*
 584          * f2fs_iget isn't quite right if the inode is currently unallocated!
 585          * However f2fs_iget currently does appropriate checks to handle stale
 586          * inodes so everything is OK.
 587          */
 588         inode = f2fs_iget(sb, ino);
 589         if (IS_ERR(inode))
 590                 return ERR_CAST(inode);
 591         if (generation && inode->i_generation != generation) {
 592                 /* we didn't find the right inode.. */
 593                 iput(inode);
 594                 return ERR_PTR(-ESTALE);
 595         }
 596         return inode;
 597 }
 598
 599 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 600                 int fh_len, int fh_type)
 601 {
 602         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 603                                     f2fs_nfs_get_inode);
 604 }
 605
 606 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 607                 int fh_len, int fh_type)
 608 {
 609         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 610                                     f2fs_nfs_get_inode);
 611 }
 612
 613 static const struct export_operations f2fs_export_ops = {
 614         .fh_to_dentry = f2fs_fh_to_dentry,
 615         .fh_to_parent = f2fs_fh_to_parent,
 616         .get_parent = f2fs_get_parent,
 617 };
 618
 619 static loff_t max_file_size(unsigned bits)
 620 {
 621         loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
 622         loff_t leaf_count = ADDRS_PER_BLOCK;
 623
 624         /* two direct node blocks */
 625         result += (leaf_count * 2);
 626
 627         /* two indirect node blocks */
 628         leaf_count *= NIDS_PER_BLOCK;
 629         result += (leaf_count * 2);
 630
 631         /* one double indirect node block */
 632         leaf_count *= NIDS_PER_BLOCK;
 633         result += leaf_count;
 634
 635         result <<= bits;
 636         return result;
 637 }
 638
 639 static int sanity_check_raw_super(struct super_block *sb,
 640                         struct f2fs_super_block *raw_super)
 641 {
 642         unsigned int blocksize;
 643
 644         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 645                 f2fs_msg(sb, KERN_INFO,
 646                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 647                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 648                 return 1;
 649         }
 650
 651         /* Currently, support only 4KB page cache size */
 652         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 653                 f2fs_msg(sb, KERN_INFO,
 654                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 655                         PAGE_CACHE_SIZE);
 656                 return 1;
 657         }
 658
 659         /* Currently, support only 4KB block size */
 660         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 661         if (blocksize != F2FS_BLKSIZE) {
 662                 f2fs_msg(sb, KERN_INFO,
 663                         "Invalid blocksize (%u), supports only 4KB\n",
 664                         blocksize);
 665                 return 1;
 666         }
 667
 668         if (le32_to_cpu(raw_super->log_sectorsize) !=
 669                                         F2FS_LOG_SECTOR_SIZE) {
 670                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
 671                 return 1;
 672         }
 673         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
 674                                         F2FS_LOG_SECTORS_PER_BLOCK) {
 675                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
 676                 return 1;
 677         }
 678         return 0;
 679 }
 680
 681 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 682 {
 683         unsigned int total, fsmeta;
 684         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 685         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 686
 687         total = le32_to_cpu(raw_super->segment_count);
 688         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 689         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 690         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 691         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 692         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 693
 694         if (fsmeta >= total)
 695                 return 1;
 696
 697         if (is_set_ckpt_flags(ckpt, CP_ERROR_FLAG)) {
 698                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 699                 return 1;
 700         }
 701         return 0;
 702 }
 703
 704 static void init_sb_info(struct f2fs_sb_info *sbi)
 705 {
 706         struct f2fs_super_block *raw_super = sbi->raw_super;
 707         int i;
 708
 709         sbi->log_sectors_per_block =
 710                 le32_to_cpu(raw_super->log_sectors_per_block);
 711         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 712         sbi->blocksize = 1 << sbi->log_blocksize;
 713         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 714         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 715         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 716         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 717         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 718         sbi->total_node_count =
 719                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 720                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 721         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 722         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 723         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 724         sbi->cur_victim_sec = NULL_SECNO;
 725
 726         for (i = 0; i < NR_COUNT_TYPE; i++)
 727                 atomic_set(&sbi->nr_pages[i], 0);
 728 }
 729
 730 static int validate_superblock(struct super_block *sb,
 731                 struct f2fs_super_block **raw_super,
 732                 struct buffer_head **raw_super_buf, sector_t block)
 733 {
 734         const char *super = (block == 0 ? "first" : "second");
 735
 736         /* read f2fs raw super block */
 737         *raw_super_buf = sb_bread(sb, block);
 738         if (!*raw_super_buf) {
 739                 f2fs_msg(sb, KERN_ERR, "unable to read %s superblock",
 740                                 super);
 741                 return -EIO;
 742         }
 743
 744         *raw_super = (struct f2fs_super_block *)
 745                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 746
 747         /* sanity checking of raw super */
 748         if (!sanity_check_raw_super(sb, *raw_super))
 749                 return 0;
 750
 751         f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem "
 752                                 "in %s superblock", super);
 753         return -EINVAL;
 754 }
 755
 756 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 757 {
 758         struct f2fs_sb_info *sbi;
 759         struct f2fs_super_block *raw_super;
 760         struct buffer_head *raw_super_buf;
 761         struct inode *root;
 762         long err = -EINVAL;
 763         int i;
 764
 765         /* allocate memory for f2fs-specific super block info */
 766         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 767         if (!sbi)
 768                 return -ENOMEM;
 769
 770         /* set a block size */
 771         if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
 772                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 773                 goto free_sbi;
 774         }
 775
 776         err = validate_superblock(sb, &raw_super, &raw_super_buf, 0);
 777         if (err) {
 778                 brelse(raw_super_buf);
 779                 /* check secondary superblock when primary failed */
 780                 err = validate_superblock(sb, &raw_super, &raw_super_buf, 1);
 781                 if (err)
 782                         goto free_sb_buf;
 783         }
 784         sb->s_fs_info = sbi;
 785         /* init some FS parameters */
 786         sbi->active_logs = NR_CURSEG_TYPE;
 787
 788         set_opt(sbi, BG_GC);
 789
 790 #ifdef CONFIG_F2FS_FS_XATTR
 791         set_opt(sbi, XATTR_USER);
 792 #endif
 793 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 794         set_opt(sbi, POSIX_ACL);
 795 #endif
 796         /* parse mount options */
 797         err = parse_options(sb, (char *)data);
 798         if (err)
 799                 goto free_sb_buf;
 800
 801         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 802         sb->s_max_links = F2FS_LINK_MAX;
 803         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 804
 805         sb->s_op = &f2fs_sops;
 806         sb->s_xattr = f2fs_xattr_handlers;
 807         sb->s_export_op = &f2fs_export_ops;
 808         sb->s_magic = F2FS_SUPER_MAGIC;
 809         sb->s_time_gran = 1;
 810         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 811                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 812         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 813
 814         /* init f2fs-specific super block info */
 815         sbi->sb = sb;
 816         sbi->raw_super = raw_super;
 817         sbi->raw_super_buf = raw_super_buf;
 818         mutex_init(&sbi->gc_mutex);
 819         mutex_init(&sbi->writepages);
 820         mutex_init(&sbi->cp_mutex);
 821         for (i = 0; i < NR_GLOBAL_LOCKS; i++)
 822                 mutex_init(&sbi->fs_lock[i]);
 823         mutex_init(&sbi->node_write);
 824         sbi->por_doing = 0;
 825         spin_lock_init(&sbi->stat_lock);
 826         init_rwsem(&sbi->bio_sem);
 827         init_sb_info(sbi);
 828
 829         /* get an inode for meta space */
 830         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 831         if (IS_ERR(sbi->meta_inode)) {
 832                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 833                 err = PTR_ERR(sbi->meta_inode);
 834                 goto free_sb_buf;
 835         }
 836
 837         err = get_valid_checkpoint(sbi);
 838         if (err) {
 839                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 840                 goto free_meta_inode;
 841         }
 842
 843         /* sanity checking of checkpoint */
 844         err = -EINVAL;
 845         if (sanity_check_ckpt(sbi)) {
 846                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 847                 goto free_cp;
 848         }
 849
 850         sbi->total_valid_node_count =
 851                                 le32_to_cpu(sbi->ckpt->valid_node_count);
 852         sbi->total_valid_inode_count =
 853                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
 854         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
 855         sbi->total_valid_block_count =
 856                                 le64_to_cpu(sbi->ckpt->valid_block_count);
 857         sbi->last_valid_block_count = sbi->total_valid_block_count;
 858         sbi->alloc_valid_block_count = 0;
 859         INIT_LIST_HEAD(&sbi->dir_inode_list);
 860         spin_lock_init(&sbi->dir_inode_lock);
 861
 862         init_orphan_info(sbi);
 863
 864         /* setup f2fs internal modules */
 865         err = build_segment_manager(sbi);
 866         if (err) {
 867                 f2fs_msg(sb, KERN_ERR,
 868                         "Failed to initialize F2FS segment manager");
 869                 goto free_sm;
 870         }
 871         err = build_node_manager(sbi);
 872         if (err) {
 873                 f2fs_msg(sb, KERN_ERR,
 874                         "Failed to initialize F2FS node manager");
 875                 goto free_nm;
 876         }
 877
 878         build_gc_manager(sbi);
 879
 880         /* get an inode for node space */
 881         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
 882         if (IS_ERR(sbi->node_inode)) {
 883                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
 884                 err = PTR_ERR(sbi->node_inode);
 885                 goto free_nm;
 886         }
 887
 888         /* if there are nt orphan nodes free them */
 889         err = -EINVAL;
 890         if (recover_orphan_inodes(sbi))
 891                 goto free_node_inode;
 892
 893         /* read root inode and dentry */
 894         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
 895         if (IS_ERR(root)) {
 896                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
 897                 err = PTR_ERR(root);
 898                 goto free_node_inode;
 899         }
 900         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size)
 901                 goto free_root_inode;
 902
 903         sb->s_root = d_make_root(root); /* allocate root dentry */
 904         if (!sb->s_root) {
 905                 err = -ENOMEM;
 906                 goto free_root_inode;
 907         }
 908
 909         /* recover fsynced data */
 910         if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
 911                 err = recover_fsync_data(sbi);
 912                 if (err)
 913                         f2fs_msg(sb, KERN_ERR,
 914                                 "Cannot recover all fsync data errno=%ld", err);
 915         }
 916
 917         /*
 918          * If filesystem is not mounted as read-only then
 919          * do start the gc_thread.
 920          */
 921         if (!(sb->s_flags & MS_RDONLY)) {
 922                 /* After POR, we can run background GC thread.*/
 923                 err = start_gc_thread(sbi);
 924                 if (err)
 925                         goto fail;
 926         }
 927
 928         err = f2fs_build_stats(sbi);
 929         if (err)
 930                 goto fail;
 931
 932         if (f2fs_proc_root)
 933                 sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
 934
 935         if (sbi->s_proc)
 936                 proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
 937                                  &f2fs_seq_segment_info_fops, sb);
 938
 939         if (test_opt(sbi, DISCARD)) {
 940                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
 941                 if (!blk_queue_discard(q))
 942                         f2fs_msg(sb, KERN_WARNING,
 943                                         "mounting with \"discard\" option, but "
 944                                         "the device does not support discard");
 945         }
 946
 947         sbi->s_kobj.kset = f2fs_kset;
 948         init_completion(&sbi->s_kobj_unregister);
 949         err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
 950                                                         "%s", sb->s_id);
 951         if (err)
 952                 goto fail;
 953
 954         return 0;
 955 fail:
 956         stop_gc_thread(sbi);
 957 free_root_inode:
 958         dput(sb->s_root);
 959         sb->s_root = NULL;
 960 free_node_inode:
 961         iput(sbi->node_inode);
 962 free_nm:
 963         destroy_node_manager(sbi);
 964 free_sm:
 965         destroy_segment_manager(sbi);
 966 free_cp:
 967         kfree(sbi->ckpt);
 968 free_meta_inode:
 969         make_bad_inode(sbi->meta_inode);
 970         iput(sbi->meta_inode);
 971 free_sb_buf:
 972         brelse(raw_super_buf);
 973 free_sbi:
 974         kfree(sbi);
 975         return err;
 976 }
 977
 978 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
 979                         const char *dev_name, void *data)
 980 {
 981         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
 982 }
 983
 984 static struct file_system_type f2fs_fs_type = {
 985         .owner          = THIS_MODULE,
 986         .name           = "f2fs",
 987         .mount          = f2fs_mount,
 988         .kill_sb        = kill_block_super,
 989         .fs_flags       = FS_REQUIRES_DEV,
 990 };
 991 MODULE_ALIAS_FS("f2fs");
 992
 993 static int __init init_inodecache(void)
 994 {
 995         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
 996                         sizeof(struct f2fs_inode_info), NULL);
 997         if (f2fs_inode_cachep == NULL)
 998                 return -ENOMEM;
 999         return 0;
1000 }
1001
1002 static void destroy_inodecache(void)
1003 {
1004         /*
1005          * Make sure all delayed rcu free inodes are flushed before we
1006          * destroy cache.
1007          */
1008         rcu_barrier();
1009         kmem_cache_destroy(f2fs_inode_cachep);
1010 }
1011
1012 static int __init init_f2fs_fs(void)
1013 {
1014         int err;
1015
1016         err = init_inodecache();
1017         if (err)
1018                 goto fail;
1019         err = create_node_manager_caches();
1020         if (err)
1021                 goto free_inodecache;
1022         err = create_gc_caches();
1023         if (err)
1024                 goto free_node_manager_caches;
1025         err = create_checkpoint_caches();
1026         if (err)
1027                 goto free_gc_caches;
1028         f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1029         if (!f2fs_kset) {
1030                 err = -ENOMEM;
1031                 goto free_checkpoint_caches;
1032         }
1033         err = register_filesystem(&f2fs_fs_type);
1034         if (err)
1035                 goto free_kset;
1036         f2fs_create_root_stats();
1037         f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1038         return 0;
1039
1040 free_kset:
1041         kset_unregister(f2fs_kset);
1042 free_checkpoint_caches:
1043         destroy_checkpoint_caches();
1044 free_gc_caches:
1045         destroy_gc_caches();
1046 free_node_manager_caches:
1047         destroy_node_manager_caches();
1048 free_inodecache:
1049         destroy_inodecache();
1050 fail:
1051         return err;
1052 }
1053
1054 static void __exit exit_f2fs_fs(void)
1055 {
1056         remove_proc_entry("fs/f2fs", NULL);
1057         f2fs_destroy_root_stats();
1058         unregister_filesystem(&f2fs_fs_type);
1059         destroy_checkpoint_caches();
1060         destroy_gc_caches();
1061         destroy_node_manager_caches();
1062         destroy_inodecache();
1063         kset_unregister(f2fs_kset);
1064 }
1065
1066 module_init(init_f2fs_fs)
1067 module_exit(exit_f2fs_fs)
1068
1069 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1070 MODULE_DESCRIPTION("Flash Friendly File System");
1071 MODULE_LICENSE("GPL");