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_flush_merge,
  55         Opt_err,
  56 };
  57
  58 static match_table_t f2fs_tokens = {
  59         {Opt_gc_background, "background_gc=%s"},
  60         {Opt_disable_roll_forward, "disable_roll_forward"},
  61         {Opt_discard, "discard"},
  62         {Opt_noheap, "no_heap"},
  63         {Opt_user_xattr, "user_xattr"},
  64         {Opt_nouser_xattr, "nouser_xattr"},
  65         {Opt_acl, "acl"},
  66         {Opt_noacl, "noacl"},
  67         {Opt_active_logs, "active_logs=%u"},
  68         {Opt_disable_ext_identify, "disable_ext_identify"},
  69         {Opt_inline_xattr, "inline_xattr"},
  70         {Opt_inline_data, "inline_data"},
  71         {Opt_flush_merge, "flush_merge"},
  72         {Opt_err, NULL},
  73 };
  74
  75 /* Sysfs support for f2fs */
  76 enum {
  77         GC_THREAD,      /* struct f2fs_gc_thread */
  78         SM_INFO,        /* struct f2fs_sm_info */
  79         NM_INFO,        /* struct f2fs_nm_info */
  80         F2FS_SBI,       /* struct f2fs_sb_info */
  81 };
  82
  83 struct f2fs_attr {
  84         struct attribute attr;
  85         ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
  86         ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
  87                          const char *, size_t);
  88         int struct_type;
  89         int offset;
  90 };
  91
  92 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
  93 {
  94         if (struct_type == GC_THREAD)
  95                 return (unsigned char *)sbi->gc_thread;
  96         else if (struct_type == SM_INFO)
  97                 return (unsigned char *)SM_I(sbi);
  98         else if (struct_type == NM_INFO)
  99                 return (unsigned char *)NM_I(sbi);
 100         else if (struct_type == F2FS_SBI)
 101                 return (unsigned char *)sbi;
 102         return NULL;
 103 }
 104
 105 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 106                         struct f2fs_sb_info *sbi, char *buf)
 107 {
 108         unsigned char *ptr = NULL;
 109         unsigned int *ui;
 110
 111         ptr = __struct_ptr(sbi, a->struct_type);
 112         if (!ptr)
 113                 return -EINVAL;
 114
 115         ui = (unsigned int *)(ptr + a->offset);
 116
 117         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
 118 }
 119
 120 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
 121                         struct f2fs_sb_info *sbi,
 122                         const char *buf, size_t count)
 123 {
 124         unsigned char *ptr;
 125         unsigned long t;
 126         unsigned int *ui;
 127         ssize_t ret;
 128
 129         ptr = __struct_ptr(sbi, a->struct_type);
 130         if (!ptr)
 131                 return -EINVAL;
 132
 133         ui = (unsigned int *)(ptr + a->offset);
 134
 135         ret = kstrtoul(skip_spaces(buf), 0, &t);
 136         if (ret < 0)
 137                 return ret;
 138         *ui = t;
 139         return count;
 140 }
 141
 142 static ssize_t f2fs_attr_show(struct kobject *kobj,
 143                                 struct attribute *attr, char *buf)
 144 {
 145         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 146                                                                 s_kobj);
 147         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 148
 149         return a->show ? a->show(a, sbi, buf) : 0;
 150 }
 151
 152 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
 153                                                 const char *buf, size_t len)
 154 {
 155         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 156                                                                         s_kobj);
 157         struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
 158
 159         return a->store ? a->store(a, sbi, buf, len) : 0;
 160 }
 161
 162 static void f2fs_sb_release(struct kobject *kobj)
 163 {
 164         struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
 165                                                                 s_kobj);
 166         complete(&sbi->s_kobj_unregister);
 167 }
 168
 169 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
 170 static struct f2fs_attr f2fs_attr_##_name = {                   \
 171         .attr = {.name = __stringify(_name), .mode = _mode },   \
 172         .show   = _show,                                        \
 173         .store  = _store,                                       \
 174         .struct_type = _struct_type,                            \
 175         .offset = _offset                                       \
 176 }
 177
 178 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)    \
 179         F2FS_ATTR_OFFSET(struct_type, name, 0644,               \
 180                 f2fs_sbi_show, f2fs_sbi_store,                  \
 181                 offsetof(struct struct_name, elname))
 182
 183 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
 184 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
 185 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
 186 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
 187 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
 188 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
 189 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
 190 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
 191 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
 192 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
 193 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
 194
 195 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 196 static struct attribute *f2fs_attrs[] = {
 197         ATTR_LIST(gc_min_sleep_time),
 198         ATTR_LIST(gc_max_sleep_time),
 199         ATTR_LIST(gc_no_gc_sleep_time),
 200         ATTR_LIST(gc_idle),
 201         ATTR_LIST(reclaim_segments),
 202         ATTR_LIST(max_small_discards),
 203         ATTR_LIST(ipu_policy),
 204         ATTR_LIST(min_ipu_util),
 205         ATTR_LIST(max_victim_search),
 206         ATTR_LIST(dir_level),
 207         ATTR_LIST(ram_thresh),
 208         NULL,
 209 };
 210
 211 static const struct sysfs_ops f2fs_attr_ops = {
 212         .show   = f2fs_attr_show,
 213         .store  = f2fs_attr_store,
 214 };
 215
 216 static struct kobj_type f2fs_ktype = {
 217         .default_attrs  = f2fs_attrs,
 218         .sysfs_ops      = &f2fs_attr_ops,
 219         .release        = f2fs_sb_release,
 220 };
 221
 222 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
 223 {
 224         struct va_format vaf;
 225         va_list args;
 226
 227         va_start(args, fmt);
 228         vaf.fmt = fmt;
 229         vaf.va = &args;
 230         printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
 231         va_end(args);
 232 }
 233
 234 static void init_once(void *foo)
 235 {
 236         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
 237
 238         inode_init_once(&fi->vfs_inode);
 239 }
 240
 241 static int parse_options(struct super_block *sb, char *options)
 242 {
 243         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 244         substring_t args[MAX_OPT_ARGS];
 245         char *p, *name;
 246         int arg = 0;
 247
 248         if (!options)
 249                 return 0;
 250
 251         while ((p = strsep(&options, ",")) != NULL) {
 252                 int token;
 253                 if (!*p)
 254                         continue;
 255                 /*
 256                  * Initialize args struct so we know whether arg was
 257                  * found; some options take optional arguments.
 258                  */
 259                 args[0].to = args[0].from = NULL;
 260                 token = match_token(p, f2fs_tokens, args);
 261
 262                 switch (token) {
 263                 case Opt_gc_background:
 264                         name = match_strdup(&args[0]);
 265
 266                         if (!name)
 267                                 return -ENOMEM;
 268                         if (strlen(name) == 2 && !strncmp(name, "on", 2))
 269                                 set_opt(sbi, BG_GC);
 270                         else if (strlen(name) == 3 && !strncmp(name, "off", 3))
 271                                 clear_opt(sbi, BG_GC);
 272                         else {
 273                                 kfree(name);
 274                                 return -EINVAL;
 275                         }
 276                         kfree(name);
 277                         break;
 278                 case Opt_disable_roll_forward:
 279                         set_opt(sbi, DISABLE_ROLL_FORWARD);
 280                         break;
 281                 case Opt_discard:
 282                         set_opt(sbi, DISCARD);
 283                         break;
 284                 case Opt_noheap:
 285                         set_opt(sbi, NOHEAP);
 286                         break;
 287 #ifdef CONFIG_F2FS_FS_XATTR
 288                 case Opt_user_xattr:
 289                         set_opt(sbi, XATTR_USER);
 290                         break;
 291                 case Opt_nouser_xattr:
 292                         clear_opt(sbi, XATTR_USER);
 293                         break;
 294                 case Opt_inline_xattr:
 295                         set_opt(sbi, INLINE_XATTR);
 296                         break;
 297 #else
 298                 case Opt_user_xattr:
 299                         f2fs_msg(sb, KERN_INFO,
 300                                 "user_xattr options not supported");
 301                         break;
 302                 case Opt_nouser_xattr:
 303                         f2fs_msg(sb, KERN_INFO,
 304                                 "nouser_xattr options not supported");
 305                         break;
 306                 case Opt_inline_xattr:
 307                         f2fs_msg(sb, KERN_INFO,
 308                                 "inline_xattr options not supported");
 309                         break;
 310 #endif
 311 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 312                 case Opt_acl:
 313                         set_opt(sbi, POSIX_ACL);
 314                         break;
 315                 case Opt_noacl:
 316                         clear_opt(sbi, POSIX_ACL);
 317                         break;
 318 #else
 319                 case Opt_acl:
 320                         f2fs_msg(sb, KERN_INFO, "acl options not supported");
 321                         break;
 322                 case Opt_noacl:
 323                         f2fs_msg(sb, KERN_INFO, "noacl options not supported");
 324                         break;
 325 #endif
 326                 case Opt_active_logs:
 327                         if (args->from && match_int(args, &arg))
 328                                 return -EINVAL;
 329                         if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
 330                                 return -EINVAL;
 331                         sbi->active_logs = arg;
 332                         break;
 333                 case Opt_disable_ext_identify:
 334                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
 335                         break;
 336                 case Opt_inline_data:
 337                         set_opt(sbi, INLINE_DATA);
 338                         break;
 339                 case Opt_flush_merge:
 340                         set_opt(sbi, FLUSH_MERGE);
 341                         break;
 342                 default:
 343                         f2fs_msg(sb, KERN_ERR,
 344                                 "Unrecognized mount option \"%s\" or missing value",
 345                                 p);
 346                         return -EINVAL;
 347                 }
 348         }
 349         return 0;
 350 }
 351
 352 static struct inode *f2fs_alloc_inode(struct super_block *sb)
 353 {
 354         struct f2fs_inode_info *fi;
 355
 356         fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
 357         if (!fi)
 358                 return NULL;
 359
 360         init_once((void *) fi);
 361
 362         /* Initialize f2fs-specific inode info */
 363         fi->vfs_inode.i_version = 1;
 364         atomic_set(&fi->dirty_dents, 0);
 365         fi->i_current_depth = 1;
 366         fi->i_advise = 0;
 367         rwlock_init(&fi->ext.ext_lock);
 368         init_rwsem(&fi->i_sem);
 369
 370         set_inode_flag(fi, FI_NEW_INODE);
 371
 372         if (test_opt(F2FS_SB(sb), INLINE_XATTR))
 373                 set_inode_flag(fi, FI_INLINE_XATTR);
 374
 375         /* Will be used by directory only */
 376         fi->i_dir_level = F2FS_SB(sb)->dir_level;
 377
 378         return &fi->vfs_inode;
 379 }
 380
 381 static int f2fs_drop_inode(struct inode *inode)
 382 {
 383         /*
 384          * This is to avoid a deadlock condition like below.
 385          * writeback_single_inode(inode)
 386          *  - f2fs_write_data_page
 387          *    - f2fs_gc -> iput -> evict
 388          *       - inode_wait_for_writeback(inode)
 389          */
 390         if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
 391                 return 0;
 392         return generic_drop_inode(inode);
 393 }
 394
 395 /*
 396  * f2fs_dirty_inode() is called from __mark_inode_dirty()
 397  *
 398  * We should call set_dirty_inode to write the dirty inode through write_inode.
 399  */
 400 static void f2fs_dirty_inode(struct inode *inode, int flags)
 401 {
 402         set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
 403 }
 404
 405 static void f2fs_i_callback(struct rcu_head *head)
 406 {
 407         struct inode *inode = container_of(head, struct inode, i_rcu);
 408         kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
 409 }
 410
 411 static void f2fs_destroy_inode(struct inode *inode)
 412 {
 413         call_rcu(&inode->i_rcu, f2fs_i_callback);
 414 }
 415
 416 static void f2fs_put_super(struct super_block *sb)
 417 {
 418         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 419
 420         if (sbi->s_proc) {
 421                 remove_proc_entry("segment_info", sbi->s_proc);
 422                 remove_proc_entry(sb->s_id, f2fs_proc_root);
 423         }
 424         kobject_del(&sbi->s_kobj);
 425
 426         f2fs_destroy_stats(sbi);
 427         stop_gc_thread(sbi);
 428
 429         /* We don't need to do checkpoint when it's clean */
 430         if (sbi->s_dirty && get_pages(sbi, F2FS_DIRTY_NODES))
 431                 write_checkpoint(sbi, true);
 432
 433         iput(sbi->node_inode);
 434         iput(sbi->meta_inode);
 435
 436         /* destroy f2fs internal modules */
 437         destroy_node_manager(sbi);
 438         destroy_segment_manager(sbi);
 439
 440         kfree(sbi->ckpt);
 441         kobject_put(&sbi->s_kobj);
 442         wait_for_completion(&sbi->s_kobj_unregister);
 443
 444         sb->s_fs_info = NULL;
 445         brelse(sbi->raw_super_buf);
 446         kfree(sbi);
 447 }
 448
 449 int f2fs_sync_fs(struct super_block *sb, int sync)
 450 {
 451         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 452
 453         trace_f2fs_sync_fs(sb, sync);
 454
 455         if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
 456                 return 0;
 457
 458         if (sync) {
 459                 mutex_lock(&sbi->gc_mutex);
 460                 write_checkpoint(sbi, false);
 461                 mutex_unlock(&sbi->gc_mutex);
 462         } else {
 463                 f2fs_balance_fs(sbi);
 464         }
 465
 466         return 0;
 467 }
 468
 469 static int f2fs_freeze(struct super_block *sb)
 470 {
 471         int err;
 472
 473         if (f2fs_readonly(sb))
 474                 return 0;
 475
 476         err = f2fs_sync_fs(sb, 1);
 477         return err;
 478 }
 479
 480 static int f2fs_unfreeze(struct super_block *sb)
 481 {
 482         return 0;
 483 }
 484
 485 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 486 {
 487         struct super_block *sb = dentry->d_sb;
 488         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 489         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 490         block_t total_count, user_block_count, start_count, ovp_count;
 491
 492         total_count = le64_to_cpu(sbi->raw_super->block_count);
 493         user_block_count = sbi->user_block_count;
 494         start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
 495         ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
 496         buf->f_type = F2FS_SUPER_MAGIC;
 497         buf->f_bsize = sbi->blocksize;
 498
 499         buf->f_blocks = total_count - start_count;
 500         buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
 501         buf->f_bavail = user_block_count - valid_user_blocks(sbi);
 502
 503         buf->f_files = sbi->total_node_count;
 504         buf->f_ffree = sbi->total_node_count - valid_inode_count(sbi);
 505
 506         buf->f_namelen = F2FS_NAME_LEN;
 507         buf->f_fsid.val[0] = (u32)id;
 508         buf->f_fsid.val[1] = (u32)(id >> 32);
 509
 510         return 0;
 511 }
 512
 513 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 514 {
 515         struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
 516
 517         if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
 518                 seq_printf(seq, ",background_gc=%s", "on");
 519         else
 520                 seq_printf(seq, ",background_gc=%s", "off");
 521         if (test_opt(sbi, DISABLE_ROLL_FORWARD))
 522                 seq_puts(seq, ",disable_roll_forward");
 523         if (test_opt(sbi, DISCARD))
 524                 seq_puts(seq, ",discard");
 525         if (test_opt(sbi, NOHEAP))
 526                 seq_puts(seq, ",no_heap_alloc");
 527 #ifdef CONFIG_F2FS_FS_XATTR
 528         if (test_opt(sbi, XATTR_USER))
 529                 seq_puts(seq, ",user_xattr");
 530         else
 531                 seq_puts(seq, ",nouser_xattr");
 532         if (test_opt(sbi, INLINE_XATTR))
 533                 seq_puts(seq, ",inline_xattr");
 534 #endif
 535 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 536         if (test_opt(sbi, POSIX_ACL))
 537                 seq_puts(seq, ",acl");
 538         else
 539                 seq_puts(seq, ",noacl");
 540 #endif
 541         if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
 542                 seq_puts(seq, ",disable_ext_identify");
 543         if (test_opt(sbi, INLINE_DATA))
 544                 seq_puts(seq, ",inline_data");
 545         if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
 546                 seq_puts(seq, ",flush_merge");
 547         seq_printf(seq, ",active_logs=%u", sbi->active_logs);
 548
 549         return 0;
 550 }
 551
 552 static int segment_info_seq_show(struct seq_file *seq, void *offset)
 553 {
 554         struct super_block *sb = seq->private;
 555         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 556         unsigned int total_segs =
 557                         le32_to_cpu(sbi->raw_super->segment_count_main);
 558         int i;
 559
 560         seq_puts(seq, "format: segment_type|valid_blocks\n"
 561                 "segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
 562
 563         for (i = 0; i < total_segs; i++) {
 564                 struct seg_entry *se = get_seg_entry(sbi, i);
 565
 566                 if ((i % 10) == 0)
 567                         seq_printf(seq, "%-5d", i);
 568                 seq_printf(seq, "%d|%-3u", se->type,
 569                                         get_valid_blocks(sbi, i, 1));
 570                 if ((i % 10) == 9 || i == (total_segs - 1))
 571                         seq_putc(seq, '\n');
 572                 else
 573                         seq_putc(seq, ' ');
 574         }
 575
 576         return 0;
 577 }
 578
 579 static int segment_info_open_fs(struct inode *inode, struct file *file)
 580 {
 581         return single_open(file, segment_info_seq_show, PDE_DATA(inode));
 582 }
 583
 584 static const struct file_operations f2fs_seq_segment_info_fops = {
 585         .owner = THIS_MODULE,
 586         .open = segment_info_open_fs,
 587         .read = seq_read,
 588         .llseek = seq_lseek,
 589         .release = single_release,
 590 };
 591
 592 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 593 {
 594         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 595         struct f2fs_mount_info org_mount_opt;
 596         int err, active_logs;
 597         bool need_restart_gc = false;
 598         bool need_stop_gc = false;
 599
 600         sync_filesystem(sb);
 601
 602         /*
 603          * Save the old mount options in case we
 604          * need to restore them.
 605          */
 606         org_mount_opt = sbi->mount_opt;
 607         active_logs = sbi->active_logs;
 608
 609         /* parse mount options */
 610         err = parse_options(sb, data);
 611         if (err)
 612                 goto restore_opts;
 613
 614         /*
 615          * Previous and new state of filesystem is RO,
 616          * so skip checking GC and FLUSH_MERGE conditions.
 617          */
 618         if ((sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
 619                 goto skip;
 620
 621         /*
 622          * We stop the GC thread if FS is mounted as RO
 623          * or if background_gc = off is passed in mount
 624          * option. Also sync the filesystem.
 625          */
 626         if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
 627                 if (sbi->gc_thread) {
 628                         stop_gc_thread(sbi);
 629                         f2fs_sync_fs(sb, 1);
 630                         need_restart_gc = true;
 631                 }
 632         } else if (test_opt(sbi, BG_GC) && !sbi->gc_thread) {
 633                 err = start_gc_thread(sbi);
 634                 if (err)
 635                         goto restore_opts;
 636                 need_stop_gc = true;
 637         }
 638
 639         /*
 640          * We stop issue flush thread if FS is mounted as RO
 641          * or if flush_merge is not passed in mount option.
 642          */
 643         if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
 644                 destroy_flush_cmd_control(sbi);
 645         } else if (test_opt(sbi, FLUSH_MERGE) &&
 646                                         !sbi->sm_info->cmd_control_info) {
 647                 err = create_flush_cmd_control(sbi);
 648                 if (err)
 649                         goto restore_gc;
 650         }
 651 skip:
 652         /* Update the POSIXACL Flag */
 653          sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 654                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 655         return 0;
 656 restore_gc:
 657         if (need_restart_gc) {
 658                 if (start_gc_thread(sbi))
 659                         f2fs_msg(sbi->sb, KERN_WARNING,
 660                                 "background gc thread is stop");
 661         } else if (need_stop_gc) {
 662                 stop_gc_thread(sbi);
 663         }
 664 restore_opts:
 665         sbi->mount_opt = org_mount_opt;
 666         sbi->active_logs = active_logs;
 667         return err;
 668 }
 669
 670 static struct super_operations f2fs_sops = {
 671         .alloc_inode    = f2fs_alloc_inode,
 672         .drop_inode     = f2fs_drop_inode,
 673         .destroy_inode  = f2fs_destroy_inode,
 674         .write_inode    = f2fs_write_inode,
 675         .dirty_inode    = f2fs_dirty_inode,
 676         .show_options   = f2fs_show_options,
 677         .evict_inode    = f2fs_evict_inode,
 678         .put_super      = f2fs_put_super,
 679         .sync_fs        = f2fs_sync_fs,
 680         .freeze_fs      = f2fs_freeze,
 681         .unfreeze_fs    = f2fs_unfreeze,
 682         .statfs         = f2fs_statfs,
 683         .remount_fs     = f2fs_remount,
 684 };
 685
 686 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
 687                 u64 ino, u32 generation)
 688 {
 689         struct f2fs_sb_info *sbi = F2FS_SB(sb);
 690         struct inode *inode;
 691
 692         if (check_nid_range(sbi, ino))
 693                 return ERR_PTR(-ESTALE);
 694
 695         /*
 696          * f2fs_iget isn't quite right if the inode is currently unallocated!
 697          * However f2fs_iget currently does appropriate checks to handle stale
 698          * inodes so everything is OK.
 699          */
 700         inode = f2fs_iget(sb, ino);
 701         if (IS_ERR(inode))
 702                 return ERR_CAST(inode);
 703         if (unlikely(generation && inode->i_generation != generation)) {
 704                 /* we didn't find the right inode.. */
 705                 iput(inode);
 706                 return ERR_PTR(-ESTALE);
 707         }
 708         return inode;
 709 }
 710
 711 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
 712                 int fh_len, int fh_type)
 713 {
 714         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 715                                     f2fs_nfs_get_inode);
 716 }
 717
 718 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
 719                 int fh_len, int fh_type)
 720 {
 721         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 722                                     f2fs_nfs_get_inode);
 723 }
 724
 725 static const struct export_operations f2fs_export_ops = {
 726         .fh_to_dentry = f2fs_fh_to_dentry,
 727         .fh_to_parent = f2fs_fh_to_parent,
 728         .get_parent = f2fs_get_parent,
 729 };
 730
 731 static loff_t max_file_size(unsigned bits)
 732 {
 733         loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
 734         loff_t leaf_count = ADDRS_PER_BLOCK;
 735
 736         /* two direct node blocks */
 737         result += (leaf_count * 2);
 738
 739         /* two indirect node blocks */
 740         leaf_count *= NIDS_PER_BLOCK;
 741         result += (leaf_count * 2);
 742
 743         /* one double indirect node block */
 744         leaf_count *= NIDS_PER_BLOCK;
 745         result += leaf_count;
 746
 747         result <<= bits;
 748         return result;
 749 }
 750
 751 static int sanity_check_raw_super(struct super_block *sb,
 752                         struct f2fs_super_block *raw_super)
 753 {
 754         unsigned int blocksize;
 755
 756         if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
 757                 f2fs_msg(sb, KERN_INFO,
 758                         "Magic Mismatch, valid(0x%x) - read(0x%x)",
 759                         F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
 760                 return 1;
 761         }
 762
 763         /* Currently, support only 4KB page cache size */
 764         if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
 765                 f2fs_msg(sb, KERN_INFO,
 766                         "Invalid page_cache_size (%lu), supports only 4KB\n",
 767                         PAGE_CACHE_SIZE);
 768                 return 1;
 769         }
 770
 771         /* Currently, support only 4KB block size */
 772         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 773         if (blocksize != F2FS_BLKSIZE) {
 774                 f2fs_msg(sb, KERN_INFO,
 775                         "Invalid blocksize (%u), supports only 4KB\n",
 776                         blocksize);
 777                 return 1;
 778         }
 779
 780         if (le32_to_cpu(raw_super->log_sectorsize) !=
 781                                         F2FS_LOG_SECTOR_SIZE) {
 782                 f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
 783                 return 1;
 784         }
 785         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
 786                                         F2FS_LOG_SECTORS_PER_BLOCK) {
 787                 f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
 788                 return 1;
 789         }
 790         return 0;
 791 }
 792
 793 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
 794 {
 795         unsigned int total, fsmeta;
 796         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
 797         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 798
 799         total = le32_to_cpu(raw_super->segment_count);
 800         fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
 801         fsmeta += le32_to_cpu(raw_super->segment_count_sit);
 802         fsmeta += le32_to_cpu(raw_super->segment_count_nat);
 803         fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
 804         fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
 805
 806         if (unlikely(fsmeta >= total))
 807                 return 1;
 808
 809         if (unlikely(is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) {
 810                 f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
 811                 return 1;
 812         }
 813         return 0;
 814 }
 815
 816 static void init_sb_info(struct f2fs_sb_info *sbi)
 817 {
 818         struct f2fs_super_block *raw_super = sbi->raw_super;
 819         int i;
 820
 821         sbi->log_sectors_per_block =
 822                 le32_to_cpu(raw_super->log_sectors_per_block);
 823         sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
 824         sbi->blocksize = 1 << sbi->log_blocksize;
 825         sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
 826         sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
 827         sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
 828         sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
 829         sbi->total_sections = le32_to_cpu(raw_super->section_count);
 830         sbi->total_node_count =
 831                 (le32_to_cpu(raw_super->segment_count_nat) / 2)
 832                         * sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
 833         sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
 834         sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
 835         sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
 836         sbi->cur_victim_sec = NULL_SECNO;
 837         sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
 838
 839         for (i = 0; i < NR_COUNT_TYPE; i++)
 840                 atomic_set(&sbi->nr_pages[i], 0);
 841
 842         sbi->dir_level = DEF_DIR_LEVEL;
 843 }
 844
 845 /*
 846  * Read f2fs raw super block.
 847  * Because we have two copies of super block, so read the first one at first,
 848  * if the first one is invalid, move to read the second one.
 849  */
 850 static int read_raw_super_block(struct super_block *sb,
 851                         struct f2fs_super_block **raw_super,
 852                         struct buffer_head **raw_super_buf)
 853 {
 854         int block = 0;
 855
 856 retry:
 857         *raw_super_buf = sb_bread(sb, block);
 858         if (!*raw_super_buf) {
 859                 f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
 860                                 block + 1);
 861                 if (block == 0) {
 862                         block++;
 863                         goto retry;
 864                 } else {
 865                         return -EIO;
 866                 }
 867         }
 868
 869         *raw_super = (struct f2fs_super_block *)
 870                 ((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
 871
 872         /* sanity checking of raw super */
 873         if (sanity_check_raw_super(sb, *raw_super)) {
 874                 brelse(*raw_super_buf);
 875                 f2fs_msg(sb, KERN_ERR,
 876                         "Can't find valid F2FS filesystem in %dth superblock",
 877                                                                 block + 1);
 878                 if (block == 0) {
 879                         block++;
 880                         goto retry;
 881                 } else {
 882                         return -EINVAL;
 883                 }
 884         }
 885
 886         return 0;
 887 }
 888
 889 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 890 {
 891         struct f2fs_sb_info *sbi;
 892         struct f2fs_super_block *raw_super;
 893         struct buffer_head *raw_super_buf;
 894         struct inode *root;
 895         long err = -EINVAL;
 896         int i;
 897
 898         /* allocate memory for f2fs-specific super block info */
 899         sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
 900         if (!sbi)
 901                 return -ENOMEM;
 902
 903         /* set a block size */
 904         if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
 905                 f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
 906                 goto free_sbi;
 907         }
 908
 909         err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
 910         if (err)
 911                 goto free_sbi;
 912
 913         sb->s_fs_info = sbi;
 914         /* init some FS parameters */
 915         sbi->active_logs = NR_CURSEG_TYPE;
 916
 917         set_opt(sbi, BG_GC);
 918
 919 #ifdef CONFIG_F2FS_FS_XATTR
 920         set_opt(sbi, XATTR_USER);
 921 #endif
 922 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 923         set_opt(sbi, POSIX_ACL);
 924 #endif
 925         /* parse mount options */
 926         err = parse_options(sb, (char *)data);
 927         if (err)
 928                 goto free_sb_buf;
 929
 930         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
 931         sb->s_max_links = F2FS_LINK_MAX;
 932         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 933
 934         sb->s_op = &f2fs_sops;
 935         sb->s_xattr = f2fs_xattr_handlers;
 936         sb->s_export_op = &f2fs_export_ops;
 937         sb->s_magic = F2FS_SUPER_MAGIC;
 938         sb->s_time_gran = 1;
 939         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
 940                 (test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
 941         memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
 942
 943         /* init f2fs-specific super block info */
 944         sbi->sb = sb;
 945         sbi->raw_super = raw_super;
 946         sbi->raw_super_buf = raw_super_buf;
 947         mutex_init(&sbi->gc_mutex);
 948         mutex_init(&sbi->writepages);
 949         mutex_init(&sbi->cp_mutex);
 950         mutex_init(&sbi->node_write);
 951         sbi->por_doing = false;
 952         spin_lock_init(&sbi->stat_lock);
 953
 954         init_rwsem(&sbi->read_io.io_rwsem);
 955         sbi->read_io.sbi = sbi;
 956         sbi->read_io.bio = NULL;
 957         for (i = 0; i < NR_PAGE_TYPE; i++) {
 958                 init_rwsem(&sbi->write_io[i].io_rwsem);
 959                 sbi->write_io[i].sbi = sbi;
 960                 sbi->write_io[i].bio = NULL;
 961         }
 962
 963         init_rwsem(&sbi->cp_rwsem);
 964         init_waitqueue_head(&sbi->cp_wait);
 965         init_sb_info(sbi);
 966
 967         /* get an inode for meta space */
 968         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
 969         if (IS_ERR(sbi->meta_inode)) {
 970                 f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
 971                 err = PTR_ERR(sbi->meta_inode);
 972                 goto free_sb_buf;
 973         }
 974
 975         err = get_valid_checkpoint(sbi);
 976         if (err) {
 977                 f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
 978                 goto free_meta_inode;
 979         }
 980
 981         /* sanity checking of checkpoint */
 982         err = -EINVAL;
 983         if (sanity_check_ckpt(sbi)) {
 984                 f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
 985                 goto free_cp;
 986         }
 987
 988         sbi->total_valid_node_count =
 989                                 le32_to_cpu(sbi->ckpt->valid_node_count);
 990         sbi->total_valid_inode_count =
 991                                 le32_to_cpu(sbi->ckpt->valid_inode_count);
 992         sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
 993         sbi->total_valid_block_count =
 994                                 le64_to_cpu(sbi->ckpt->valid_block_count);
 995         sbi->last_valid_block_count = sbi->total_valid_block_count;
 996         sbi->alloc_valid_block_count = 0;
 997         INIT_LIST_HEAD(&sbi->dir_inode_list);
 998         spin_lock_init(&sbi->dir_inode_lock);
 999
1000         init_orphan_info(sbi);
1001
1002         /* setup f2fs internal modules */
1003         err = build_segment_manager(sbi);
1004         if (err) {
1005                 f2fs_msg(sb, KERN_ERR,
1006                         "Failed to initialize F2FS segment manager");
1007                 goto free_sm;
1008         }
1009         err = build_node_manager(sbi);
1010         if (err) {
1011                 f2fs_msg(sb, KERN_ERR,
1012                         "Failed to initialize F2FS node manager");
1013                 goto free_nm;
1014         }
1015
1016         build_gc_manager(sbi);
1017
1018         /* get an inode for node space */
1019         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1020         if (IS_ERR(sbi->node_inode)) {
1021                 f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1022                 err = PTR_ERR(sbi->node_inode);
1023                 goto free_nm;
1024         }
1025
1026         /* if there are nt orphan nodes free them */
1027         recover_orphan_inodes(sbi);
1028
1029         /* read root inode and dentry */
1030         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1031         if (IS_ERR(root)) {
1032                 f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1033                 err = PTR_ERR(root);
1034                 goto free_node_inode;
1035         }
1036         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1037                 err = -EINVAL;
1038                 goto free_root_inode;
1039         }
1040
1041         sb->s_root = d_make_root(root); /* allocate root dentry */
1042         if (!sb->s_root) {
1043                 err = -ENOMEM;
1044                 goto free_root_inode;
1045         }
1046
1047         err = f2fs_build_stats(sbi);
1048         if (err)
1049                 goto free_root_inode;
1050
1051         if (f2fs_proc_root)
1052                 sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1053
1054         if (sbi->s_proc)
1055                 proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1056                                  &f2fs_seq_segment_info_fops, sb);
1057
1058         if (test_opt(sbi, DISCARD)) {
1059                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
1060                 if (!blk_queue_discard(q))
1061                         f2fs_msg(sb, KERN_WARNING,
1062                                         "mounting with \"discard\" option, but "
1063                                         "the device does not support discard");
1064         }
1065
1066         sbi->s_kobj.kset = f2fs_kset;
1067         init_completion(&sbi->s_kobj_unregister);
1068         err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1069                                                         "%s", sb->s_id);
1070         if (err)
1071                 goto free_proc;
1072
1073         /* recover fsynced data */
1074         if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1075                 err = recover_fsync_data(sbi);
1076                 if (err)
1077                         f2fs_msg(sb, KERN_ERR,
1078                                 "Cannot recover all fsync data errno=%ld", err);
1079         }
1080
1081         /*
1082          * If filesystem is not mounted as read-only then
1083          * do start the gc_thread.
1084          */
1085         if (!(sb->s_flags & MS_RDONLY)) {
1086                 /* After POR, we can run background GC thread.*/
1087                 err = start_gc_thread(sbi);
1088                 if (err)
1089                         goto free_kobj;
1090         }
1091         return 0;
1092
1093 free_kobj:
1094         kobject_del(&sbi->s_kobj);
1095 free_proc:
1096         if (sbi->s_proc) {
1097                 remove_proc_entry("segment_info", sbi->s_proc);
1098                 remove_proc_entry(sb->s_id, f2fs_proc_root);
1099         }
1100         f2fs_destroy_stats(sbi);
1101 free_root_inode:
1102         dput(sb->s_root);
1103         sb->s_root = NULL;
1104 free_node_inode:
1105         iput(sbi->node_inode);
1106 free_nm:
1107         destroy_node_manager(sbi);
1108 free_sm:
1109         destroy_segment_manager(sbi);
1110 free_cp:
1111         kfree(sbi->ckpt);
1112 free_meta_inode:
1113         make_bad_inode(sbi->meta_inode);
1114         iput(sbi->meta_inode);
1115 free_sb_buf:
1116         brelse(raw_super_buf);
1117 free_sbi:
1118         kfree(sbi);
1119         return err;
1120 }
1121
1122 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1123                         const char *dev_name, void *data)
1124 {
1125         return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1126 }
1127
1128 static struct file_system_type f2fs_fs_type = {
1129         .owner          = THIS_MODULE,
1130         .name           = "f2fs",
1131         .mount          = f2fs_mount,
1132         .kill_sb        = kill_block_super,
1133         .fs_flags       = FS_REQUIRES_DEV,
1134 };
1135 MODULE_ALIAS_FS("f2fs");
1136
1137 static int __init init_inodecache(void)
1138 {
1139         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1140                         sizeof(struct f2fs_inode_info));
1141         if (!f2fs_inode_cachep)
1142                 return -ENOMEM;
1143         return 0;
1144 }
1145
1146 static void destroy_inodecache(void)
1147 {
1148         /*
1149          * Make sure all delayed rcu free inodes are flushed before we
1150          * destroy cache.
1151          */
1152         rcu_barrier();
1153         kmem_cache_destroy(f2fs_inode_cachep);
1154 }
1155
1156 static int __init init_f2fs_fs(void)
1157 {
1158         int err;
1159
1160         err = init_inodecache();
1161         if (err)
1162                 goto fail;
1163         err = create_node_manager_caches();
1164         if (err)
1165                 goto free_inodecache;
1166         err = create_segment_manager_caches();
1167         if (err)
1168                 goto free_node_manager_caches;
1169         err = create_gc_caches();
1170         if (err)
1171                 goto free_segment_manager_caches;
1172         err = create_checkpoint_caches();
1173         if (err)
1174                 goto free_gc_caches;
1175         f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1176         if (!f2fs_kset) {
1177                 err = -ENOMEM;
1178                 goto free_checkpoint_caches;
1179         }
1180         err = register_filesystem(&f2fs_fs_type);
1181         if (err)
1182                 goto free_kset;
1183         f2fs_create_root_stats();
1184         f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1185         return 0;
1186
1187 free_kset:
1188         kset_unregister(f2fs_kset);
1189 free_checkpoint_caches:
1190         destroy_checkpoint_caches();
1191 free_gc_caches:
1192         destroy_gc_caches();
1193 free_segment_manager_caches:
1194         destroy_segment_manager_caches();
1195 free_node_manager_caches:
1196         destroy_node_manager_caches();
1197 free_inodecache:
1198         destroy_inodecache();
1199 fail:
1200         return err;
1201 }
1202
1203 static void __exit exit_f2fs_fs(void)
1204 {
1205         remove_proc_entry("fs/f2fs", NULL);
1206         f2fs_destroy_root_stats();
1207         unregister_filesystem(&f2fs_fs_type);
1208         destroy_checkpoint_caches();
1209         destroy_gc_caches();
1210         destroy_segment_manager_caches();
1211         destroy_node_manager_caches();
1212         destroy_inodecache();
1213         kset_unregister(f2fs_kset);
1214 }
1215
1216 module_init(init_f2fs_fs)
1217 module_exit(exit_f2fs_fs)
1218
1219 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1220 MODULE_DESCRIPTION("Flash Friendly File System");
1221 MODULE_LICENSE("GPL");