Pileus Git - ~andy/linux/blob - 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_user_xattr,
  47         Opt_nouser_xattr,
  48         Opt_acl,
  49         Opt_noacl,
  50         Opt_active_logs,
  51         Opt_disable_ext_identify,
  52         Opt_inline_xattr,
  53         Opt_inline_data,
  54         Opt_err,
  55 };
  56
  57 static match_table_t f2fs_tokens = {
  58         {Opt_gc_background, "background_gc=%s"},
  59         {Opt_disable_roll_forward, "disable_roll_forward"},
  60         {Opt_discard, "discard"},
  61         {Opt_noheap, "no_heap"},
  62         {Opt_user_xattr, "user_xattr"},
  63         {Opt_nouser_xattr, "nouser_xattr"},
  64         {Opt_acl, "acl"},
  65         {Opt_noacl, "noacl"},
  66         {Opt_active_logs, "active_logs=%u"},
  67         {Opt_disable_ext_identify, "disable_ext_identify"},
  68         {Opt_inline_xattr, "inline_xattr"},
  69         {Opt_inline_data, "inline_data"},
  70         {Opt_err, NULL},
  71 };
  72
  73 /* Sysfs support for f2fs */
  74 enum {
  75         GC_THREAD,      /* struct f2fs_gc_thread */
  76         SM_INFO,        /* struct f2fs_sm_info */
  77         F2FS_SBI,       /* struct f2fs_sb_info */
  78 };
  79
  80 struct f2fs_attr {
  81         struct attribute attr;
  82         ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
  83         ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
  84                          const char *, size_t);
  85         int struct_type;
  86         int offset;
  87 };
  88
  89 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
  90 {
  91         if (struct_type == GC_THREAD)
  92                 return (unsigned char *)sbi->gc_thread;
  93         else if (struct_type == SM_INFO)
  94                 return (unsigned char *)SM_I(sbi);
  95         else if (struct_type == F2FS_SBI)
  96                 return (unsigned char *)sbi;
  97         return NULL;
  98 }
  99
 100 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 101                         struct f2fs_sb_info *sbi, char *buf)
 102 {
 103         unsigned char *ptr = NULL;
 104         unsigned int *ui;
 105
 106         ptr = __struct_ptr(sbi, a->struct_type);
 107         if (!ptr)
 108                 return -EINVAL;
 109
 110         ui = (unsigned int *)(ptr + a->offset);
 111
 112         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
 113 }
 114
 115 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
 116                         struct f2fs_sb_info *sbi,
 117                         const char *buf, size_t count)
 118 {
 119         unsigned char *ptr;
 120         unsigned long t;
 121         unsigned int *ui;
 122         ssize_t ret;
 123
 124         ptr = __struct_ptr(sbi, a->struct_type);
 125         if (!ptr)
 126                 return -EINVAL;
 127
 128         ui = (unsigned int *)(ptr + a->offset);
 129
 130         ret = kstrtoul(skip_spaces(buf), 0, &t);
 131         if (ret < 0)
 132                 return ret;
 133         *ui = t;
 134         return count;
 135 }
 136
 137 static ssize_t f2fs_attr_show(struct kobject *kobj,
 138                                 struct attribute *attr, char *buf)
 139 {
 140         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 141                                                                 s_kobj);
 142         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 143
 144         return a->show ? a->show(a, sbi, buf) : 0;
 145 }
 146
 147 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
 148                                                 const char *buf, size_t len)
 149 {
 150         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 151                                                                         s_kobj);
 152         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 153
 154         return a->store ? a->store(a, sbi, buf, len) : 0;
 155 }
 156
 157 static void f2fs_sb_release(struct kobject *kobj)
 158 {
 159         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 160                                                                 s_kobj);
 161         complete(&sbi->s_kobj_unregister);
 162 }
 163
 164 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
 165 static struct f2fs_attr f2fs_attr_##_name = {                   \
 166         .attr = {.name = __stringify(_name), .mode = _mode },   \
 167         .show   = _show,                                        \
 168         .store  = _store,                                       \
 169         .struct_type = _struct_type,                            \
 170         .offset = _offset                                       \
 171 }
 172
 173 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)    \
 174         F2FS_ATTR_OFFSET(struct_type, name, 0644,               \
 175                 f2fs_sbi_show, f2fs_sbi_store,                  \
 176                 offsetof(struct struct_name, elname))
 177
 178 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
 179 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
 180 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
 181 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
 182 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
 183 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
 184 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
 185 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
 186 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
 187
 188 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 189 static struct attribute *f2fs_attrs[] = {
 190         ATTR_LIST(gc_min_sleep_time),
 191         ATTR_LIST(gc_max_sleep_time),
 192         ATTR_LIST(gc_no_gc_sleep_time),
 193         ATTR_LIST(gc_idle),
 194         ATTR_LIST(reclaim_segments),
 195         ATTR_LIST(max_small_discards),
 196         ATTR_LIST(ipu_policy),
 197         ATTR_LIST(min_ipu_util),
 198         ATTR_LIST(max_victim_search),
 199         NULL,
 200 };
 201
 202 static const struct sysfs_ops f2fs_attr_ops = {
 203         .show   = f2fs_attr_show,
 204         .store  = f2fs_attr_store,
 205 };
 206
 207 static struct kobj_type f2fs_ktype = {
 208         .default_attrs  = f2fs_attrs,
 209         .sysfs_ops      = &f2fs_attr_ops,
 210         .release        = f2fs_sb_release,
 211 };
 212
 213 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
 214 {
 215         struct va_format vaf;
 216         va_list args;
 217
 218         va_start(args, fmt);
 219         vaf.fmt = fmt;
 220         vaf.va = &args;
 221         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
 222         va_end(args);
 223 }
 224
 225 static void init_once(void *foo)
 226 {
 227         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
 228
 229         inode_init_once(&fi->vfs_inode);
 230 }
 231
 232 static int parse_options(struct super_block *sb, char *options)
 233 {
 234         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 235         substring_t args[MAX_OPT_ARGS];
 236         char *p, *name;
 237         int arg = 0;
 238
 239         if (!options)
 240                 return 0;
 241
 242         while ((p = strsep(&options, ",")) != NULL) {
 243                 int token;
 244                 if (!*p)
 245                         continue;
 246                 /*
 247                  * Initialize args struct so we know whether arg was
 248                  * found; some options take optional arguments.
 249                  */
 250                 args[0].to = args[0].from = NULL;
 251                 token = match_token(p, f2fs_tokens, args);
 252
 253                 switch (token) {
 254                 case Opt_gc_background:
 255                         name = match_strdup(&args[0]);
 256
 257                         if (!name)
 258                                 return -ENOMEM;
 259                         if (!strncmp(name, "on", 2))
 260                                 set_opt(sbi, BG_GC);
 261                         else if (!strncmp(name, "off", 3))
 262                                 clear_opt(sbi, BG_GC);
 263                         else {
 264                                 kfree(name);
 265                                 return -EINVAL;
 266                         }
 267                         kfree(name);
 268                         break;
 269                 case Opt_disable_roll_forward:
 270                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 271                         break;
 272                 case Opt_discard:
 273                         set_opt(sbi, DISCARD);
 274                         break;
 275                 case Opt_noheap:
 276                         set_opt(sbi, NOHEAP);
 277                         break;
 278 #ifdef CONFIG_F2FS_FS_XATTR
 279                 case Opt_user_xattr:
 280                         set_opt(sbi, XATTR_USER);
 281                         break;
 282                 case Opt_nouser_xattr:
 283                         clear_opt(sbi, XATTR_USER);
 284                         break;
 285                 case Opt_inline_xattr:
 286                         set_opt(sbi, INLINE_XATTR);
 287                         break;
 288 #else
 289                 case Opt_user_xattr:
 290                         f2fs_msg(sb, KERN_INFO,
 291                                 "user_xattr options not supported");
 292                         break;
 293                 case Opt_nouser_xattr:
 294                         f2fs_msg(sb, KERN_INFO,
 295                                 "nouser_xattr options not supported");
 296                         break;
 297                 case Opt_inline_xattr:
 298                         f2fs_msg(sb, KERN_INFO,
 299                                 "inline_xattr options not supported");
 300                         break;
 301 #endif
 302 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 303                 case Opt_acl:
 304                         set_opt(sbi, POSIX_ACL);
 305                         break;
 306                 case Opt_noacl:
 307                         clear_opt(sbi, POSIX_ACL);
 308                         break;
 309 #else
 310                 case Opt_acl:
 311                         f2fs_msg(sb, KERN_INFO, "acl options not supported");
 312                         break;
 313                 case Opt_noacl:
 314                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 315                         break;
 316 #endif
 317                 case Opt_active_logs:
 318                         if (args->from && match_int(args, &arg))
 319                                 return -EINVAL;
 320                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 321                                 return -EINVAL;
 322                         sbi->active_logs = arg;
 323                         break;
 324                 case Opt_disable_ext_identify:
 325                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 326                         break;
 327                 case Opt_inline_data:
 328                         set_opt(sbi, INLINE_DATA);
 329                         break;
 330                 default:
 331                         f2fs_msg(sb, KERN_ERR,
 332                                 "Unrecognized mount option \"%s\" or missing value",
 333                                 p);
 334                         return -EINVAL;
 335                 }
 336         }
 337         return 0;
 338 }
 339
 340 static struct inode *f2fs_alloc_inode(struct super_block *sb)
 341 {
 342         struct f2fs_inode_info *fi;
 343
 344         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
 345         if (!fi)
 346                 return NULL;
 347
 348         init_once((void *) fi);
 349
 350         /* Initialize f2fs-specific inode info */
 351         fi->vfs_inode.i_version = 1;
 352         atomic_set(&fi->dirty_dents, 0);
 353         fi->i_current_depth = 1;
 354         fi->i_advise = 0;
 355         rwlock_init(&fi->ext.ext_lock);
 356
 357         set_inode_flag(fi, FI_NEW_INODE);
 358
 359         if (test_opt(F2FS_SB(sb), INLINE_XATTR))
 360                 set_inode_flag(fi, FI_INLINE_XATTR);
 361
 362         return &fi->vfs_inode;
 363 }
 364
 365 static int f2fs_drop_inode(struct inode *inode)
 366 {
 367         /*
 368          * This is to avoid a deadlock condition like below.
 369          * writeback_single_inode(inode)
 370          *  - f2fs_write_data_page
 371          *    - f2fs_gc -> iput -> evict
 372          *       - inode_wait_for_writeback(inode)
 373          */
 374         if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
 375                 return 0;
 376         return generic_drop_inode(inode);
 377 }
 378
 379 /*
 380  * f2fs_dirty_inode() is called from __mark_inode_dirty()
 381  *
 382  * We should call set_dirty_inode to write the dirty inode through write_inode.
 383  */
 384 static void f2fs_dirty_inode(struct inode *inode, int flags)
 385 {
 386         set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
 387 }
 388
 389 static void f2fs_i_callback(struct rcu_head *head)
 390 {
 391         struct inode *inode = container_of(head, struct inode, i_rcu);
 392         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 393 }
 394
 395 static void f2fs_destroy_inode(struct inode *inode)
 396 {
 397         call_rcu(&inode->i_rcu, f2fs_i_callback);
 398 }
 399
 400 static void f2fs_put_super(struct super_block *sb)
 401 {
 402         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 403
 404         if (sbi->s_proc) {
 405                 remove_proc_entry("segment_info", sbi->s_proc);
 406                 remove_proc_entry(sb->s_id, f2fs_proc_root);
 407         }
 408         kobject_del(&sbi->s_kobj);
 409
 410         f2fs_destroy_stats(sbi);
 411         stop_gc_thread(sbi);
 412
 413         /* We don't need to do checkpoint when it's clean */
 414         if (sbi->s_dirty && get_pages(sbi, F2FS_DIRTY_NODES))
 415                 write_checkpoint(sbi, true);
 416
 417         iput(sbi->node_inode);
 418         iput(sbi->meta_inode);
 419
 420         /* destroy f2fs internal modules */
 421         destroy_node_manager(sbi);
 422         destroy_segment_manager(sbi);
 423
 424         kfree(sbi->ckpt);
 425         kobject_put(&sbi->s_kobj);
 426         wait_for_completion(&sbi->s_kobj_unregister);
 427
 428         sb->s_fs_info = NULL;
 429         brelse(sbi->raw_super_buf);
 430         kfree(sbi);
 431 }
 432
 433 int f2fs_sync_fs(struct super_block *sb, int sync)
 434 {
 435         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 436
 437         trace_f2fs_sync_fs(sb, sync);
 438
 439         if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
 440                 return 0;
 441
 442         if (sync) {
 443                 mutex_lock(&sbi->gc_mutex);
 444                 write_checkpoint(sbi, false);
 445                 mutex_unlock(&sbi->gc_mutex);
 446         } else {
 447                 f2fs_balance_fs(sbi);
 448         }
 449
 450         return 0;
 451 }
 452
 453 static int f2fs_freeze(struct super_block *sb)
 454 {
 455         int err;
 456
 457         if (f2fs_readonly(sb))
 458                 return 0;
 459
 460         err = f2fs_sync_fs(sb, 1);
 461         return err;
 462 }
 463
 464 static int f2fs_unfreeze(struct super_block *sb)
 465 {
 466         return 0;
 467 }
 468
 469 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 470 {
 471         struct super_block *sb = dentry->d_sb;
 472         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 473         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 474         block_t total_count, user_block_count, start_count, ovp_count;
 475
 476         total_count = le64_to_cpu(sbi->raw_super->block_count);
 477         user_block_count = sbi->user_block_count;
 478         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 479         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 480         buf->f_type = F2FS_SUPER_MAGIC;
 481         buf->f_bsize = sbi->blocksize;
 482
 483         buf->f_blocks = total_count - start_count;
 484         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 485         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 486
 487         buf->f_files = sbi->total_node_count;
 488         buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
 489
 490         buf->f_namelen = F2FS_NAME_LEN;
 491         buf->f_fsid.val[0] = (u32)id;
 492         buf->f_fsid.val[1] = (u32)(id >> 32);
 493
 494         return 0;
 495 }
 496
 497 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 498 {
 499         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 500
 501         if (!(root->d_sb->s_flags & MS_RDONLY) && test_opt(sbi, BG_GC))
 502                 seq_printf(seq, ",background_gc=%s", "on");
 503         else
 504                 seq_printf(seq, ",background_gc=%s", "off");
 505         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 506                 seq_puts(seq, ",disable_roll_forward");
 507         if (test_opt(sbi, DISCARD))
 508                 seq_puts(seq, ",discard");
 509         if (test_opt(sbi, NOHEAP))
 510                 seq_puts(seq, ",no_heap_alloc");
 511 #ifdef CONFIG_F2FS_FS_XATTR
 512         if (test_opt(sbi, XATTR_USER))
 513                 seq_puts(seq, ",user_xattr");
 514         else
 515                 seq_puts(seq, ",nouser_xattr");
 516         if (test_opt(sbi, INLINE_XATTR))
 517                 seq_puts(seq, ",inline_xattr");
 518 #endif
 519 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 520         if (test_opt(sbi, POSIX_ACL))
 521                 seq_puts(seq, ",acl");
 522         else
 523                 seq_puts(seq, ",noacl");
 524 #endif
 525         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 526                 seq_puts(seq, ",disable_ext_identify");
 527         if (test_opt(sbi, INLINE_DATA))
 528                 seq_puts(seq, ",inline_data");
 529         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 530
 531         return 0;
 532 }
 533
 534 static int segment_info_seq_show(struct seq_file *seq, void *offset)
 535 {
 536         struct super_block *sb = seq->private;
 537         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 538         unsigned int total_segs =
 539                         le32_to_cpu(sbi->raw_super->segment_count_main);
 540         int i;
 541
 542         for (i = 0; i < total_segs; i++) {
 543                 seq_printf(seq, "%u", get_valid_blocks(sbi, i, 1));
 544                 if (i != 0 && (i % 10) == 0)
 545                         seq_puts(seq, "\n");
 546                 else
 547                         seq_puts(seq, " ");
 548         }
 549         return 0;
 550 }
 551
 552 static int segment_info_open_fs(struct inode *inode, struct file *file)
 553 {
 554         return single_open(file, segment_info_seq_show, PDE_DATA(inode));
 555 }
 556
 557 static const struct file_operations f2fs_seq_segment_info_fops = {
 558         .owner = THIS_MODULE,
 559         .open = segment_info_open_fs,
 560         .read = seq_read,
 561         .llseek = seq_lseek,
 562         .release = single_release,
 563 };
 564
 565 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 566 {
 567         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 568         struct f2fs_mount_info org_mount_opt;
 569         int err, active_logs;
 570
 571         /*
 572          * Save the old mount options in case we
 573          * need to restore them.
 574          */
 575         org_mount_opt = sbi->mount_opt;
 576         active_logs = sbi->active_logs;
 577
 578         /* parse mount options */
 579         err = parse_options(sb, data);
 580         if (err)
 581                 goto restore_opts;
 582
 583         /*
 584          * Previous and new state of filesystem is RO,
 585          * so no point in checking GC conditions.
 586          */
 587         if ((sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
 588                 goto skip;
 589
 590         /*
 591          * We stop the GC thread if FS is mounted as RO
 592          * or if background_gc = off is passed in mount
 593          * option. Also sync the filesystem.
 594          */
 595         if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
 596                 if (sbi->gc_thread) {
 597                         stop_gc_thread(sbi);
 598                         f2fs_sync_fs(sb, 1);
 599                 }
 600         } else if (test_opt(sbi, BG_GC) && !sbi->gc_thread) {
 601                 err = start_gc_thread(sbi);
 602                 if (err)
 603                         goto restore_opts;
 604         }
 605 skip:
 606         /* Update the POSIXACL Flag */
 607          sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 608                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 609         return 0;
 610
 611 restore_opts:
 612         sbi->mount_opt = org_mount_opt;
 613         sbi->active_logs = active_logs;
 614         return err;
 615 }
 616
 617 static struct super_operations f2fs_sops = {
 618         .alloc_inode    = f2fs_alloc_inode,
 619         .drop_inode     = f2fs_drop_inode,
 620         .destroy_inode  = f2fs_destroy_inode,
 621         .write_inode    = f2fs_write_inode,
 622         .dirty_inode    = f2fs_dirty_inode,
 623         .show_options   = f2fs_show_options,
 624         .evict_inode    = f2fs_evict_inode,
 625         .put_super      = f2fs_put_super,
 626         .sync_fs        = f2fs_sync_fs,
 627         .freeze_fs      = f2fs_freeze,
 628         .unfreeze_fs    = f2fs_unfreeze,
 629         .statfs         = f2fs_statfs,
 630         .remount_fs     = f2fs_remount,
 631 };
 632
 633 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 634                 u64 ino, u32 generation)
 635 {
 636         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 637         struct inode *inode;
 638
 639         if (unlikely(ino < F2FS_ROOT_INO(sbi)))
 640                 return ERR_PTR(-ESTALE);
 641
 642         /*
 643          * f2fs_iget isn't quite right if the inode is currently unallocated!
 644          * However f2fs_iget currently does appropriate checks to handle stale
 645          * inodes so everything is OK.
 646          */
 647         inode = f2fs_iget(sb, ino);
 648         if (IS_ERR(inode))
 649                 return ERR_CAST(inode);
 650         if (unlikely(generation && inode->i_generation != generation)) {
 651                 /* we didn't find the right inode.. */
 652                 iput(inode);
 653                 return ERR_PTR(-ESTALE);
 654         }
 655         return inode;
 656 }
 657
 658 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 659                 int fh_len, int fh_type)
 660 {
 661         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 662                                     f2fs_nfs_get_inode);
 663 }
 664
 665 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 666                 int fh_len, int fh_type)
 667 {
 668         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 669                                     f2fs_nfs_get_inode);
 670 }
 671
 672 static const struct export_operations f2fs_export_ops = {
 673         .fh_to_dentry = f2fs_fh_to_dentry,
 674         .fh_to_parent = f2fs_fh_to_parent,
 675         .get_parent = f2fs_get_parent,
 676 };
 677
 678 static loff_t max_file_size(unsigned bits)
 679 {
 680         loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
 681         loff_t leaf_count = ADDRS_PER_BLOCK;
 682
 683         /* two direct node blocks */
 684         result += (leaf_count * 2);
 685
 686         /* two indirect node blocks */
 687         leaf_count *= NIDS_PER_BLOCK;
 688         result += (leaf_count * 2);
 689
 690         /* one double indirect node block */
 691         leaf_count *= NIDS_PER_BLOCK;
 692         result += leaf_count;
 693
 694         result <<= bits;
 695         return result;
 696 }
 697
 698 static int sanity_check_raw_super(struct super_block *sb,
 699                         struct f2fs_super_block *raw_super)
 700 {
 701         unsigned int blocksize;
 702
 703         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 704                 f2fs_msg(sb, KERN_INFO,
 705                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 706                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 707                 return 1;
 708         }
 709
 710         /* Currently, support only 4KB page cache size */
 711         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 712                 f2fs_msg(sb, KERN_INFO,
 713                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 714                         PAGE_CACHE_SIZE);
 715                 return 1;
 716         }
 717
 718         /* Currently, support only 4KB block size */
 719         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 720         if (blocksize != F2FS_BLKSIZE) {
 721                 f2fs_msg(sb, KERN_INFO,
 722                         "Invalid blocksize (%u), supports only 4KB\n",
 723                         blocksize);
 724                 return 1;
 725         }
 726
 727         if (le32_to_cpu(raw_super->log_sectorsize) !=
 728                                         F2FS_LOG_SECTOR_SIZE) {
 729                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
 730                 return 1;
 731         }
 732         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
 733                                         F2FS_LOG_SECTORS_PER_BLOCK) {
 734                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
 735                 return 1;
 736         }
 737         return 0;
 738 }
 739
 740 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 741 {
 742         unsigned int total, fsmeta;
 743         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 744         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 745
 746         total = le32_to_cpu(raw_super->segment_count);
 747         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 748         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 749         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 750         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 751         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 752
 753         if (unlikely(fsmeta >= total))
 754                 return 1;
 755
 756         if (unlikely(is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) {
 757                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 758                 return 1;
 759         }
 760         return 0;
 761 }
 762
 763 static void init_sb_info(struct f2fs_sb_info *sbi)
 764 {
 765         struct f2fs_super_block *raw_super = sbi->raw_super;
 766         int i;
 767
 768         sbi->log_sectors_per_block =
 769                 le32_to_cpu(raw_super->log_sectors_per_block);
 770         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 771         sbi->blocksize = 1 << sbi->log_blocksize;
 772         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 773         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 774         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 775         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 776         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 777         sbi->total_node_count =
 778                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 779                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 780         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 781         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 782         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 783         sbi->cur_victim_sec = NULL_SECNO;
 784         sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
 785
 786         for (i = 0; i < NR_COUNT_TYPE; i++)
 787                 atomic_set(&sbi->nr_pages[i], 0);
 788 }
 789
 790 /*
 791  * Read f2fs raw super block.
 792  * Because we have two copies of super block, so read the first one at first,
 793  * if the first one is invalid, move to read the second one.
 794  */
 795 static int read_raw_super_block(struct super_block *sb,
 796                         struct f2fs_super_block **raw_super,
 797                         struct buffer_head **raw_super_buf)
 798 {
 799         int block = 0;
 800
 801 retry:
 802         *raw_super_buf = sb_bread(sb, block);
 803         if (!*raw_super_buf) {
 804                 f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
 805                                 block + 1);
 806                 if (block == 0) {
 807                         block++;
 808                         goto retry;
 809                 } else {
 810                         return -EIO;
 811                 }
 812         }
 813
 814         *raw_super = (struct f2fs_super_block *)
 815                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 816
 817         /* sanity checking of raw super */
 818         if (sanity_check_raw_super(sb, *raw_super)) {
 819                 brelse(*raw_super_buf);
 820                 f2fs_msg(sb, KERN_ERR,
 821                         "Can't find valid F2FS filesystem in %dth superblock",
 822                                                                 block + 1);
 823                 if (block == 0) {
 824                         block++;
 825                         goto retry;
 826                 } else {
 827                         return -EINVAL;
 828                 }
 829         }
 830
 831         return 0;
 832 }
 833
 834 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 835 {
 836         struct f2fs_sb_info *sbi;
 837         struct f2fs_super_block *raw_super;
 838         struct buffer_head *raw_super_buf;
 839         struct inode *root;
 840         long err = -EINVAL;
 841         int i;
 842
 843         /* allocate memory for f2fs-specific super block info */
 844         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 845         if (!sbi)
 846                 return -ENOMEM;
 847
 848         /* set a block size */
 849         if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
 850                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 851                 goto free_sbi;
 852         }
 853
 854         err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
 855         if (err)
 856                 goto free_sbi;
 857
 858         sb->s_fs_info = sbi;
 859         /* init some FS parameters */
 860         sbi->active_logs = NR_CURSEG_TYPE;
 861
 862         set_opt(sbi, BG_GC);
 863
 864 #ifdef CONFIG_F2FS_FS_XATTR
 865         set_opt(sbi, XATTR_USER);
 866 #endif
 867 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 868         set_opt(sbi, POSIX_ACL);
 869 #endif
 870         /* parse mount options */
 871         err = parse_options(sb, (char *)data);
 872         if (err)
 873                 goto free_sb_buf;
 874
 875         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 876         sb->s_max_links = F2FS_LINK_MAX;
 877         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 878
 879         sb->s_op = &f2fs_sops;
 880         sb->s_xattr = f2fs_xattr_handlers;
 881         sb->s_export_op = &f2fs_export_ops;
 882         sb->s_magic = F2FS_SUPER_MAGIC;
 883         sb->s_time_gran = 1;
 884         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 885                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 886         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 887
 888         /* init f2fs-specific super block info */
 889         sbi->sb = sb;
 890         sbi->raw_super = raw_super;
 891         sbi->raw_super_buf = raw_super_buf;
 892         mutex_init(&sbi->gc_mutex);
 893         mutex_init(&sbi->writepages);
 894         mutex_init(&sbi->cp_mutex);
 895         mutex_init(&sbi->node_write);
 896         sbi->por_doing = false;
 897         spin_lock_init(&sbi->stat_lock);
 898
 899         mutex_init(&sbi->read_io.io_mutex);
 900         sbi->read_io.sbi = sbi;
 901         sbi->read_io.bio = NULL;
 902         for (i = 0; i < NR_PAGE_TYPE; i++) {
 903                 mutex_init(&sbi->write_io[i].io_mutex);
 904                 sbi->write_io[i].sbi = sbi;
 905                 sbi->write_io[i].bio = NULL;
 906         }
 907
 908         init_rwsem(&sbi->cp_rwsem);
 909         init_waitqueue_head(&sbi->cp_wait);
 910         init_sb_info(sbi);
 911
 912         /* get an inode for meta space */
 913         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 914         if (IS_ERR(sbi->meta_inode)) {
 915                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 916                 err = PTR_ERR(sbi->meta_inode);
 917                 goto free_sb_buf;
 918         }
 919
 920         err = get_valid_checkpoint(sbi);
 921         if (err) {
 922                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 923                 goto free_meta_inode;
 924         }
 925
 926         /* sanity checking of checkpoint */
 927         err = -EINVAL;
 928         if (sanity_check_ckpt(sbi)) {
 929                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 930                 goto free_cp;
 931         }
 932
 933         sbi->total_valid_node_count =
 934                                 le32_to_cpu(sbi->ckpt->valid_node_count);
 935         sbi->total_valid_inode_count =
 936                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
 937         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
 938         sbi->total_valid_block_count =
 939                                 le64_to_cpu(sbi->ckpt->valid_block_count);
 940         sbi->last_valid_block_count = sbi->total_valid_block_count;
 941         sbi->alloc_valid_block_count = 0;
 942         INIT_LIST_HEAD(&sbi->dir_inode_list);
 943         spin_lock_init(&sbi->dir_inode_lock);
 944
 945         init_orphan_info(sbi);
 946
 947         /* setup f2fs internal modules */
 948         err = build_segment_manager(sbi);
 949         if (err) {
 950                 f2fs_msg(sb, KERN_ERR,
 951                         "Failed to initialize F2FS segment manager");
 952                 goto free_sm;
 953         }
 954         err = build_node_manager(sbi);
 955         if (err) {
 956                 f2fs_msg(sb, KERN_ERR,
 957                         "Failed to initialize F2FS node manager");
 958                 goto free_nm;
 959         }
 960
 961         build_gc_manager(sbi);
 962
 963         /* get an inode for node space */
 964         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
 965         if (IS_ERR(sbi->node_inode)) {
 966                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
 967                 err = PTR_ERR(sbi->node_inode);
 968                 goto free_nm;
 969         }
 970
 971         /* if there are nt orphan nodes free them */
 972         recover_orphan_inodes(sbi);
 973
 974         /* read root inode and dentry */
 975         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
 976         if (IS_ERR(root)) {
 977                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
 978                 err = PTR_ERR(root);
 979                 goto free_node_inode;
 980         }
 981         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
 982                 err = -EINVAL;
 983                 goto free_root_inode;
 984         }
 985
 986         sb->s_root = d_make_root(root); /* allocate root dentry */
 987         if (!sb->s_root) {
 988                 err = -ENOMEM;
 989                 goto free_root_inode;
 990         }
 991
 992         /* recover fsynced data */
 993         if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
 994                 err = recover_fsync_data(sbi);
 995                 if (err)
 996                         f2fs_msg(sb, KERN_ERR,
 997                                 "Cannot recover all fsync data errno=%ld", err);
 998         }
 999
1000         /*
1001          * If filesystem is not mounted as read-only then
1002          * do start the gc_thread.
1003          */
1004         if (!(sb->s_flags & MS_RDONLY)) {
1005                 /* After POR, we can run background GC thread.*/
1006                 err = start_gc_thread(sbi);
1007                 if (err)
1008                         goto free_gc;
1009         }
1010
1011         err = f2fs_build_stats(sbi);
1012         if (err)
1013                 goto free_gc;
1014
1015         if (f2fs_proc_root)
1016                 sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1017
1018         if (sbi->s_proc)
1019                 proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1020                                  &f2fs_seq_segment_info_fops, sb);
1021
1022         if (test_opt(sbi, DISCARD)) {
1023                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
1024                 if (!blk_queue_discard(q))
1025                         f2fs_msg(sb, KERN_WARNING,
1026                                         "mounting with \"discard\" option, but "
1027                                         "the device does not support discard");
1028         }
1029
1030         sbi->s_kobj.kset = f2fs_kset;
1031         init_completion(&sbi->s_kobj_unregister);
1032         err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1033                                                         "%s", sb->s_id);
1034         if (err)
1035                 goto fail;
1036
1037         return 0;
1038 fail:
1039         if (sbi->s_proc) {
1040                 remove_proc_entry("segment_info", sbi->s_proc);
1041                 remove_proc_entry(sb->s_id, f2fs_proc_root);
1042         }
1043         f2fs_destroy_stats(sbi);
1044 free_gc:
1045         stop_gc_thread(sbi);
1046 free_root_inode:
1047         dput(sb->s_root);
1048         sb->s_root = NULL;
1049 free_node_inode:
1050         iput(sbi->node_inode);
1051 free_nm:
1052         destroy_node_manager(sbi);
1053 free_sm:
1054         destroy_segment_manager(sbi);
1055 free_cp:
1056         kfree(sbi->ckpt);
1057 free_meta_inode:
1058         make_bad_inode(sbi->meta_inode);
1059         iput(sbi->meta_inode);
1060 free_sb_buf:
1061         brelse(raw_super_buf);
1062 free_sbi:
1063         kfree(sbi);
1064         return err;
1065 }
1066
1067 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1068                         const char *dev_name, void *data)
1069 {
1070         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1071 }
1072
1073 static struct file_system_type f2fs_fs_type = {
1074         .owner          = THIS_MODULE,
1075         .name           = "f2fs",
1076         .mount          = f2fs_mount,
1077         .kill_sb        = kill_block_super,
1078         .fs_flags       = FS_REQUIRES_DEV,
1079 };
1080 MODULE_ALIAS_FS("f2fs");
1081
1082 static int __init init_inodecache(void)
1083 {
1084         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1085                         sizeof(struct f2fs_inode_info), NULL);
1086         if (!f2fs_inode_cachep)
1087                 return -ENOMEM;
1088         return 0;
1089 }
1090
1091 static void destroy_inodecache(void)
1092 {
1093         /*
1094          * Make sure all delayed rcu free inodes are flushed before we
1095          * destroy cache.
1096          */
1097         rcu_barrier();
1098         kmem_cache_destroy(f2fs_inode_cachep);
1099 }
1100
1101 static int __init init_f2fs_fs(void)
1102 {
1103         int err;
1104
1105         err = init_inodecache();
1106         if (err)
1107                 goto fail;
1108         err = create_node_manager_caches();
1109         if (err)
1110                 goto free_inodecache;
1111         err = create_segment_manager_caches();
1112         if (err)
1113                 goto free_node_manager_caches;
1114         err = create_gc_caches();
1115         if (err)
1116                 goto free_segment_manager_caches;
1117         err = create_checkpoint_caches();
1118         if (err)
1119                 goto free_gc_caches;
1120         f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1121         if (!f2fs_kset) {
1122                 err = -ENOMEM;
1123                 goto free_checkpoint_caches;
1124         }
1125         err = register_filesystem(&f2fs_fs_type);
1126         if (err)
1127                 goto free_kset;
1128         f2fs_create_root_stats();
1129         f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1130         return 0;
1131
1132 free_kset:
1133         kset_unregister(f2fs_kset);
1134 free_checkpoint_caches:
1135         destroy_checkpoint_caches();
1136 free_gc_caches:
1137         destroy_gc_caches();
1138 free_segment_manager_caches:
1139         destroy_segment_manager_caches();
1140 free_node_manager_caches:
1141         destroy_node_manager_caches();
1142 free_inodecache:
1143         destroy_inodecache();
1144 fail:
1145         return err;
1146 }
1147
1148 static void __exit exit_f2fs_fs(void)
1149 {
1150         remove_proc_entry("fs/f2fs", NULL);
1151         f2fs_destroy_root_stats();
1152         unregister_filesystem(&f2fs_fs_type);
1153         destroy_checkpoint_caches();
1154         destroy_gc_caches();
1155         destroy_segment_manager_caches();
1156         destroy_node_manager_caches();
1157         destroy_inodecache();
1158         kset_unregister(f2fs_kset);
1159 }
1160
1161 module_init(init_f2fs_fs)
1162 module_exit(exit_f2fs_fs)
1163
1164 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1165 MODULE_DESCRIPTION("Flash Friendly File System");
1166 MODULE_LICENSE("GPL");