1/*
   2 *  linux/fs/ext4/super.c
   3 *
   4 * Copyright (C) 1992, 1993, 1994, 1995
   5 * Remy Card (card@masi.ibp.fr)
   6 * Laboratoire MASI - Institut Blaise Pascal
   7 * Universite Pierre et Marie Curie (Paris VI)
   8 *
   9 *  from
  10 *
  11 *  linux/fs/minix/inode.c
  12 *
  13 *  Copyright (C) 1991, 1992  Linus Torvalds
  14 *
  15 *  Big-endian to little-endian byte-swapping/bitmaps by
  16 *        David S. Miller (davem@caip.rutgers.edu), 1995
  17 */
  18
  19#include <linux/module.h>
  20#include <linux/string.h>
  21#include <linux/fs.h>
  22#include <linux/time.h>
  23#include <linux/vmalloc.h>
  24#include <linux/jbd2.h>
  25#include <linux/slab.h>
  26#include <linux/init.h>
  27#include <linux/blkdev.h>
 
  28#include <linux/parser.h>
  29#include <linux/buffer_head.h>
  30#include <linux/exportfs.h>
  31#include <linux/vfs.h>
  32#include <linux/random.h>
  33#include <linux/mount.h>
  34#include <linux/namei.h>
  35#include <linux/quotaops.h>
  36#include <linux/seq_file.h>
  37#include <linux/proc_fs.h>
  38#include <linux/ctype.h>
  39#include <linux/log2.h>
  40#include <linux/crc16.h>
  41#include <linux/cleancache.h>
  42#include <asm/uaccess.h>
  43
 
 
  44#include <linux/kthread.h>
  45#include <linux/freezer.h>
 
 
 
  46
  47#include "ext4.h"
  48#include "ext4_extents.h"
  49#include "ext4_jbd2.h"
  50#include "xattr.h"
  51#include "acl.h"
  52#include "mballoc.h"
 
  53
  54#define CREATE_TRACE_POINTS
  55#include <trace/events/ext4.h>
  56
  57static struct proc_dir_entry *ext4_proc_root;
  58static struct kset *ext4_kset;
  59static struct ext4_lazy_init *ext4_li_info;
  60static struct mutex ext4_li_mtx;
  61static struct ext4_features *ext4_feat;
  62
  63static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64			     unsigned long journal_devnum);
  65static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  66static int ext4_commit_super(struct super_block *sb, int sync);
  67static void ext4_mark_recovery_complete(struct super_block *sb,
 
  68					struct ext4_super_block *es);
  69static void ext4_clear_journal_err(struct super_block *sb,
  70				   struct ext4_super_block *es);
  71static int ext4_sync_fs(struct super_block *sb, int wait);
  72static const char *ext4_decode_error(struct super_block *sb, int errno,
  73				     char nbuf[16]);
  74static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76static int ext4_unfreeze(struct super_block *sb);
  77static void ext4_write_super(struct super_block *sb);
  78static int ext4_freeze(struct super_block *sb);
  79static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  80		       const char *dev_name, void *data);
  81static inline int ext2_feature_set_ok(struct super_block *sb);
  82static inline int ext3_feature_set_ok(struct super_block *sb);
  83static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  84static void ext4_destroy_lazyinit_thread(void);
  85static void ext4_unregister_li_request(struct super_block *sb);
  86static void ext4_clear_request_list(void);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  87
  88#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 
 
 
 
 
 
 
 
  89static struct file_system_type ext2_fs_type = {
  90	.owner		= THIS_MODULE,
  91	.name		= "ext2",
  92	.mount		= ext4_mount,
  93	.kill_sb	= kill_block_super,
  94	.fs_flags	= FS_REQUIRES_DEV,
 
  95};
  96#define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 
 
  97#else
  98#define IS_EXT2_SB(sb) (0)
  99#endif
 100
 101
 102#if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 103static struct file_system_type ext3_fs_type = {
 104	.owner		= THIS_MODULE,
 105	.name		= "ext3",
 106	.mount		= ext4_mount,
 107	.kill_sb	= kill_block_super,
 108	.fs_flags	= FS_REQUIRES_DEV,
 
 109};
 110#define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 111#else
 112#define IS_EXT3_SB(sb) (0)
 113#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 114
 115static int ext4_verify_csum_type(struct super_block *sb,
 116				 struct ext4_super_block *es)
 117{
 118	if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 119					EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 120		return 1;
 121
 122	return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 123}
 124
 125static __le32 ext4_superblock_csum(struct super_block *sb,
 126				   struct ext4_super_block *es)
 127{
 128	struct ext4_sb_info *sbi = EXT4_SB(sb);
 129	int offset = offsetof(struct ext4_super_block, s_checksum);
 130	__u32 csum;
 131
 132	csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 133
 134	return cpu_to_le32(csum);
 135}
 136
 137int ext4_superblock_csum_verify(struct super_block *sb,
 138				struct ext4_super_block *es)
 139{
 140	if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 141				       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 142		return 1;
 143
 144	return es->s_checksum == ext4_superblock_csum(sb, es);
 145}
 146
 147void ext4_superblock_csum_set(struct super_block *sb,
 148			      struct ext4_super_block *es)
 149{
 150	if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 151		EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 
 152		return;
 153
 154	es->s_checksum = ext4_superblock_csum(sb, es);
 155}
 156
 157void *ext4_kvmalloc(size_t size, gfp_t flags)
 158{
 159	void *ret;
 160
 161	ret = kmalloc(size, flags);
 162	if (!ret)
 163		ret = __vmalloc(size, flags, PAGE_KERNEL);
 164	return ret;
 165}
 166
 167void *ext4_kvzalloc(size_t size, gfp_t flags)
 168{
 169	void *ret;
 170
 171	ret = kzalloc(size, flags);
 172	if (!ret)
 173		ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 174	return ret;
 175}
 176
 177void ext4_kvfree(void *ptr)
 178{
 179	if (is_vmalloc_addr(ptr))
 180		vfree(ptr);
 181	else
 182		kfree(ptr);
 183
 184}
 185
 186ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 187			       struct ext4_group_desc *bg)
 188{
 189	return le32_to_cpu(bg->bg_block_bitmap_lo) |
 190		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 191		 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 192}
 193
 194ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 195			       struct ext4_group_desc *bg)
 196{
 197	return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 198		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 199		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 200}
 201
 202ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 203			      struct ext4_group_desc *bg)
 204{
 205	return le32_to_cpu(bg->bg_inode_table_lo) |
 206		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 207		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 208}
 209
 210__u32 ext4_free_group_clusters(struct super_block *sb,
 211			       struct ext4_group_desc *bg)
 212{
 213	return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 214		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 215		 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 216}
 217
 218__u32 ext4_free_inodes_count(struct super_block *sb,
 219			      struct ext4_group_desc *bg)
 220{
 221	return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 222		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 223		 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 224}
 225
 226__u32 ext4_used_dirs_count(struct super_block *sb,
 227			      struct ext4_group_desc *bg)
 228{
 229	return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 230		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 231		 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 232}
 233
 234__u32 ext4_itable_unused_count(struct super_block *sb,
 235			      struct ext4_group_desc *bg)
 236{
 237	return le16_to_cpu(bg->bg_itable_unused_lo) |
 238		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 239		 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 240}
 241
 242void ext4_block_bitmap_set(struct super_block *sb,
 243			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
 244{
 245	bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 246	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 247		bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 248}
 249
 250void ext4_inode_bitmap_set(struct super_block *sb,
 251			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
 252{
 253	bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 254	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 255		bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 256}
 257
 258void ext4_inode_table_set(struct super_block *sb,
 259			  struct ext4_group_desc *bg, ext4_fsblk_t blk)
 260{
 261	bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 262	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 263		bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 264}
 265
 266void ext4_free_group_clusters_set(struct super_block *sb,
 267				  struct ext4_group_desc *bg, __u32 count)
 268{
 269	bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 270	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 271		bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 272}
 273
 274void ext4_free_inodes_set(struct super_block *sb,
 275			  struct ext4_group_desc *bg, __u32 count)
 276{
 277	bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 278	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 279		bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 280}
 281
 282void ext4_used_dirs_set(struct super_block *sb,
 283			  struct ext4_group_desc *bg, __u32 count)
 284{
 285	bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 286	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 287		bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 288}
 289
 290void ext4_itable_unused_set(struct super_block *sb,
 291			  struct ext4_group_desc *bg, __u32 count)
 292{
 293	bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 294	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 295		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 296}
 297
 298
 299/* Just increment the non-pointer handle value */
 300static handle_t *ext4_get_nojournal(void)
 301{
 302	handle_t *handle = current->journal_info;
 303	unsigned long ref_cnt = (unsigned long)handle;
 304
 305	BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 306
 307	ref_cnt++;
 308	handle = (handle_t *)ref_cnt;
 309
 310	current->journal_info = handle;
 311	return handle;
 312}
 313
 314
 315/* Decrement the non-pointer handle value */
 316static void ext4_put_nojournal(handle_t *handle)
 317{
 318	unsigned long ref_cnt = (unsigned long)handle;
 319
 320	BUG_ON(ref_cnt == 0);
 321
 322	ref_cnt--;
 323	handle = (handle_t *)ref_cnt;
 324
 325	current->journal_info = handle;
 326}
 
 
 
 
 
 
 
 
 327
 328/*
 329 * Wrappers for jbd2_journal_start/end.
 
 330 *
 331 * The only special thing we need to do here is to make sure that all
 332 * journal_end calls result in the superblock being marked dirty, so
 333 * that sync() will call the filesystem's write_super callback if
 334 * appropriate.
 
 335 *
 336 * To avoid j_barrier hold in userspace when a user calls freeze(),
 337 * ext4 prevents a new handle from being started by s_frozen, which
 338 * is in an upper layer.
 339 */
 340handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 341{
 342	journal_t *journal;
 343	handle_t  *handle;
 
 
 
 
 
 344
 345	trace_ext4_journal_start(sb, nblocks, _RET_IP_);
 346	if (sb->s_flags & MS_RDONLY)
 347		return ERR_PTR(-EROFS);
 348
 349	journal = EXT4_SB(sb)->s_journal;
 350	handle = ext4_journal_current_handle();
 351
 352	/*
 353	 * If a handle has been started, it should be allowed to
 354	 * finish, otherwise deadlock could happen between freeze
 355	 * and others(e.g. truncate) due to the restart of the
 356	 * journal handle if the filesystem is forzen and active
 357	 * handles are not stopped.
 358	 */
 359	if (!handle)
 360		vfs_check_frozen(sb, SB_FREEZE_TRANS);
 361
 362	if (!journal)
 363		return ext4_get_nojournal();
 364	/*
 365	 * Special case here: if the journal has aborted behind our
 366	 * backs (eg. EIO in the commit thread), then we still need to
 367	 * take the FS itself readonly cleanly.
 
 
 
 368	 */
 369	if (is_journal_aborted(journal)) {
 370		ext4_abort(sb, "Detected aborted journal");
 371		return ERR_PTR(-EROFS);
 372	}
 373	return jbd2_journal_start(journal, nblocks);
 374}
 375
 376/*
 377 * The only special thing we need to do here is to make sure that all
 378 * jbd2_journal_stop calls result in the superblock being marked dirty, so
 379 * that sync() will call the filesystem's write_super callback if
 380 * appropriate.
 381 */
 382int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 383{
 384	struct super_block *sb;
 385	int err;
 386	int rc;
 
 387
 388	if (!ext4_handle_valid(handle)) {
 389		ext4_put_nojournal(handle);
 390		return 0;
 391	}
 392	sb = handle->h_transaction->t_journal->j_private;
 393	err = handle->h_err;
 394	rc = jbd2_journal_stop(handle);
 395
 396	if (!err)
 397		err = rc;
 398	if (err)
 399		__ext4_std_error(sb, where, line, err);
 400	return err;
 
 
 
 
 
 
 
 
 401}
 402
 403void ext4_journal_abort_handle(const char *caller, unsigned int line,
 404			       const char *err_fn, struct buffer_head *bh,
 405			       handle_t *handle, int err)
 406{
 407	char nbuf[16];
 408	const char *errstr = ext4_decode_error(NULL, err, nbuf);
 
 
 
 
 
 
 
 
 
 
 
 409
 410	BUG_ON(!ext4_handle_valid(handle));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 411
 412	if (bh)
 413		BUFFER_TRACE(bh, "abort");
 
 414
 415	if (!handle->h_err)
 416		handle->h_err = err;
 
 
 
 
 
 
 
 417
 418	if (is_handle_aborted(handle))
 419		return;
 
 
 420
 421	printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
 422	       caller, line, errstr, err_fn);
 
 423
 424	jbd2_journal_abort_handle(handle);
 
 
 
 
 425}
 426
 427static void __save_error_info(struct super_block *sb, const char *func,
 428			    unsigned int line)
 429{
 430	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 431
 432	EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 433	es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 434	es->s_last_error_time = cpu_to_le32(get_seconds());
 435	strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 436	es->s_last_error_line = cpu_to_le32(line);
 437	if (!es->s_first_error_time) {
 438		es->s_first_error_time = es->s_last_error_time;
 439		strncpy(es->s_first_error_func, func,
 440			sizeof(es->s_first_error_func));
 441		es->s_first_error_line = cpu_to_le32(line);
 442		es->s_first_error_ino = es->s_last_error_ino;
 443		es->s_first_error_block = es->s_last_error_block;
 444	}
 445	/*
 446	 * Start the daily error reporting function if it hasn't been
 447	 * started already
 448	 */
 449	if (!es->s_error_count)
 450		mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 451	es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 452}
 453
 454static void save_error_info(struct super_block *sb, const char *func,
 455			    unsigned int line)
 456{
 457	__save_error_info(sb, func, line);
 458	ext4_commit_super(sb, 1);
 459}
 460
 461/*
 462 * The del_gendisk() function uninitializes the disk-specific data
 463 * structures, including the bdi structure, without telling anyone
 464 * else.  Once this happens, any attempt to call mark_buffer_dirty()
 465 * (for example, by ext4_commit_super), will cause a kernel OOPS.
 466 * This is a kludge to prevent these oops until we can put in a proper
 467 * hook in del_gendisk() to inform the VFS and file system layers.
 468 */
 469static int block_device_ejected(struct super_block *sb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 470{
 471	struct inode *bd_inode = sb->s_bdev->bd_inode;
 472	struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 473
 474	return bdi->dev == NULL;
 
 
 
 475}
 476
 477static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 
 
 478{
 479	struct super_block		*sb = journal->j_private;
 480	struct ext4_sb_info		*sbi = EXT4_SB(sb);
 481	int				error = is_journal_aborted(journal);
 482	struct ext4_journal_cb_entry	*jce, *tmp;
 483
 484	spin_lock(&sbi->s_md_lock);
 485	list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
 486		list_del_init(&jce->jce_list);
 487		spin_unlock(&sbi->s_md_lock);
 488		jce->jce_func(sb, jce, error);
 489		spin_lock(&sbi->s_md_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 490	}
 491	spin_unlock(&sbi->s_md_lock);
 492}
 493
 494/* Deal with the reporting of failure conditions on a filesystem such as
 495 * inconsistencies detected or read IO failures.
 496 *
 497 * On ext2, we can store the error state of the filesystem in the
 498 * superblock.  That is not possible on ext4, because we may have other
 499 * write ordering constraints on the superblock which prevent us from
 500 * writing it out straight away; and given that the journal is about to
 501 * be aborted, we can't rely on the current, or future, transactions to
 502 * write out the superblock safely.
 503 *
 504 * We'll just use the jbd2_journal_abort() error code to record an error in
 505 * the journal instead.  On recovery, the journal will complain about
 506 * that error until we've noted it down and cleared it.
 
 
 
 
 
 
 507 */
 508
 509static void ext4_handle_error(struct super_block *sb)
 
 510{
 511	if (sb->s_flags & MS_RDONLY)
 512		return;
 513
 514	if (!test_opt(sb, ERRORS_CONT)) {
 515		journal_t *journal = EXT4_SB(sb)->s_journal;
 
 516
 517		EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 
 518		if (journal)
 519			jbd2_journal_abort(journal, -EIO);
 520	}
 521	if (test_opt(sb, ERRORS_RO)) {
 522		ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 523		sb->s_flags |= MS_RDONLY;
 
 
 
 
 
 
 
 
 
 
 524	}
 525	if (test_opt(sb, ERRORS_PANIC))
 
 
 
 
 
 
 526		panic("EXT4-fs (device %s): panic forced after error\n",
 527			sb->s_id);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 528}
 529
 
 
 
 
 530void __ext4_error(struct super_block *sb, const char *function,
 531		  unsigned int line, const char *fmt, ...)
 
 532{
 533	struct va_format vaf;
 534	va_list args;
 535
 536	va_start(args, fmt);
 537	vaf.fmt = fmt;
 538	vaf.va = &args;
 539	printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 540	       sb->s_id, function, line, current->comm, &vaf);
 541	va_end(args);
 542	save_error_info(sb, function, line);
 543
 544	ext4_handle_error(sb);
 
 
 
 
 
 
 
 
 
 
 
 
 545}
 546
 547void ext4_error_inode(struct inode *inode, const char *function,
 548		      unsigned int line, ext4_fsblk_t block,
 549		      const char *fmt, ...)
 550{
 551	va_list args;
 552	struct va_format vaf;
 553	struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 554
 555	es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 556	es->s_last_error_block = cpu_to_le64(block);
 557	save_error_info(inode->i_sb, function, line);
 558	va_start(args, fmt);
 559	vaf.fmt = fmt;
 560	vaf.va = &args;
 561	if (block)
 562		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 563		       "inode #%lu: block %llu: comm %s: %pV\n",
 564		       inode->i_sb->s_id, function, line, inode->i_ino,
 565		       block, current->comm, &vaf);
 566	else
 567		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 568		       "inode #%lu: comm %s: %pV\n",
 569		       inode->i_sb->s_id, function, line, inode->i_ino,
 570		       current->comm, &vaf);
 571	va_end(args);
 572
 573	ext4_handle_error(inode->i_sb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 574}
 575
 576void ext4_error_file(struct file *file, const char *function,
 577		     unsigned int line, ext4_fsblk_t block,
 578		     const char *fmt, ...)
 579{
 580	va_list args;
 581	struct va_format vaf;
 582	struct ext4_super_block *es;
 583	struct inode *inode = file->f_dentry->d_inode;
 584	char pathname[80], *path;
 585
 586	es = EXT4_SB(inode->i_sb)->s_es;
 587	es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 588	save_error_info(inode->i_sb, function, line);
 589	path = d_path(&(file->f_path), pathname, sizeof(pathname));
 590	if (IS_ERR(path))
 591		path = "(unknown)";
 592	va_start(args, fmt);
 593	vaf.fmt = fmt;
 594	vaf.va = &args;
 595	if (block)
 596		printk(KERN_CRIT
 597		       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 598		       "block %llu: comm %s: path %s: %pV\n",
 599		       inode->i_sb->s_id, function, line, inode->i_ino,
 600		       block, current->comm, path, &vaf);
 601	else
 602		printk(KERN_CRIT
 603		       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 604		       "comm %s: path %s: %pV\n",
 605		       inode->i_sb->s_id, function, line, inode->i_ino,
 606		       current->comm, path, &vaf);
 607	va_end(args);
 608
 609	ext4_handle_error(inode->i_sb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 610}
 611
 612static const char *ext4_decode_error(struct super_block *sb, int errno,
 613				     char nbuf[16])
 614{
 615	char *errstr = NULL;
 616
 617	switch (errno) {
 
 
 
 
 
 
 618	case -EIO:
 619		errstr = "IO failure";
 620		break;
 621	case -ENOMEM:
 622		errstr = "Out of memory";
 623		break;
 624	case -EROFS:
 625		if (!sb || (EXT4_SB(sb)->s_journal &&
 626			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 627			errstr = "Journal has aborted";
 628		else
 629			errstr = "Readonly filesystem";
 630		break;
 631	default:
 632		/* If the caller passed in an extra buffer for unknown
 633		 * errors, textualise them now.  Else we just return
 634		 * NULL. */
 635		if (nbuf) {
 636			/* Check for truncated error codes... */
 637			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 638				errstr = nbuf;
 639		}
 640		break;
 641	}
 642
 643	return errstr;
 644}
 645
 646/* __ext4_std_error decodes expected errors from journaling functions
 647 * automatically and invokes the appropriate error response.  */
 648
 649void __ext4_std_error(struct super_block *sb, const char *function,
 650		      unsigned int line, int errno)
 651{
 652	char nbuf[16];
 653	const char *errstr;
 654
 
 
 
 655	/* Special case: if the error is EROFS, and we're not already
 656	 * inside a transaction, then there's really no point in logging
 657	 * an error. */
 658	if (errno == -EROFS && journal_current_handle() == NULL &&
 659	    (sb->s_flags & MS_RDONLY))
 660		return;
 661
 662	errstr = ext4_decode_error(sb, errno, nbuf);
 663	printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 664	       sb->s_id, function, line, errstr);
 665	save_error_info(sb, function, line);
 
 
 666
 667	ext4_handle_error(sb);
 668}
 669
 670/*
 671 * ext4_abort is a much stronger failure handler than ext4_error.  The
 672 * abort function may be used to deal with unrecoverable failures such
 673 * as journal IO errors or ENOMEM at a critical moment in log management.
 674 *
 675 * We unconditionally force the filesystem into an ABORT|READONLY state,
 676 * unless the error response on the fs has been set to panic in which
 677 * case we take the easy way out and panic immediately.
 678 */
 679
 680void __ext4_abort(struct super_block *sb, const char *function,
 681		unsigned int line, const char *fmt, ...)
 682{
 
 683	va_list args;
 684
 685	save_error_info(sb, function, line);
 
 
 
 
 
 
 686	va_start(args, fmt);
 687	printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 688	       function, line);
 689	vprintk(fmt, args);
 690	printk("\n");
 
 
 691	va_end(args);
 
 692
 693	if ((sb->s_flags & MS_RDONLY) == 0) {
 694		ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 695		sb->s_flags |= MS_RDONLY;
 696		EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 697		if (EXT4_SB(sb)->s_journal)
 698			jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 699		save_error_info(sb, function, line);
 700	}
 701	if (test_opt(sb, ERRORS_PANIC))
 702		panic("EXT4-fs panic from previous error\n");
 703}
 704
 705void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 
 706{
 707	struct va_format vaf;
 708	va_list args;
 709
 
 
 
 710	va_start(args, fmt);
 711	vaf.fmt = fmt;
 712	vaf.va = &args;
 713	printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 
 714	va_end(args);
 715}
 716
 717void __ext4_warning(struct super_block *sb, const char *function,
 718		    unsigned int line, const char *fmt, ...)
 719{
 720	struct va_format vaf;
 721	va_list args;
 722
 
 
 
 723	va_start(args, fmt);
 724	vaf.fmt = fmt;
 725	vaf.va = &args;
 726	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 727	       sb->s_id, function, line, &vaf);
 
 728	va_end(args);
 729}
 730
 731void __ext4_grp_locked_error(const char *function, unsigned int line,
 732			     struct super_block *sb, ext4_group_t grp,
 733			     unsigned long ino, ext4_fsblk_t block,
 734			     const char *fmt, ...)
 735__releases(bitlock)
 736__acquires(bitlock)
 737{
 738	struct va_format vaf;
 739	va_list args;
 740	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 741
 742	es->s_last_error_ino = cpu_to_le32(ino);
 743	es->s_last_error_block = cpu_to_le64(block);
 744	__save_error_info(sb, function, line);
 745
 746	va_start(args, fmt);
 
 747
 748	vaf.fmt = fmt;
 749	vaf.va = &args;
 750	printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 751	       sb->s_id, function, line, grp);
 752	if (ino)
 753		printk(KERN_CONT "inode %lu: ", ino);
 754	if (block)
 755		printk(KERN_CONT "block %llu:", (unsigned long long) block);
 756	printk(KERN_CONT "%pV\n", &vaf);
 757	va_end(args);
 
 
 
 
 
 758
 759	if (test_opt(sb, ERRORS_CONT)) {
 760		ext4_commit_super(sb, 0);
 
 
 
 
 
 
 
 761		return;
 762	}
 763
 764	ext4_unlock_group(sb, grp);
 765	ext4_handle_error(sb);
 766	/*
 767	 * We only get here in the ERRORS_RO case; relocking the group
 768	 * may be dangerous, but nothing bad will happen since the
 769	 * filesystem will have already been marked read/only and the
 770	 * journal has been aborted.  We return 1 as a hint to callers
 771	 * who might what to use the return value from
 772	 * ext4_grp_locked_error() to distinguish between the
 773	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 774	 * aggressively from the ext4 function in question, with a
 775	 * more appropriate error code.
 776	 */
 777	ext4_lock_group(sb, grp);
 778	return;
 779}
 780
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 781void ext4_update_dynamic_rev(struct super_block *sb)
 782{
 783	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 784
 785	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 786		return;
 787
 788	ext4_warning(sb,
 789		     "updating to rev %d because of new feature flag, "
 790		     "running e2fsck is recommended",
 791		     EXT4_DYNAMIC_REV);
 792
 793	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 794	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 795	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 796	/* leave es->s_feature_*compat flags alone */
 797	/* es->s_uuid will be set by e2fsck if empty */
 798
 799	/*
 800	 * The rest of the superblock fields should be zero, and if not it
 801	 * means they are likely already in use, so leave them alone.  We
 802	 * can leave it up to e2fsck to clean up any inconsistencies there.
 803	 */
 804}
 805
 806/*
 807 * Open the external journal device
 808 */
 809static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 810{
 811	struct block_device *bdev;
 812	char b[BDEVNAME_SIZE];
 813
 814	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 815	if (IS_ERR(bdev))
 816		goto fail;
 817	return bdev;
 818
 819fail:
 820	ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 821			__bdevname(dev, b), PTR_ERR(bdev));
 822	return NULL;
 823}
 824
 825/*
 826 * Release the journal device
 827 */
 828static int ext4_blkdev_put(struct block_device *bdev)
 829{
 830	return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 831}
 832
 833static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 834{
 835	struct block_device *bdev;
 836	int ret = -ENODEV;
 837
 838	bdev = sbi->journal_bdev;
 839	if (bdev) {
 840		ret = ext4_blkdev_put(bdev);
 841		sbi->journal_bdev = NULL;
 842	}
 843	return ret;
 844}
 845
 846static inline struct inode *orphan_list_entry(struct list_head *l)
 847{
 848	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 849}
 850
 851static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 852{
 853	struct list_head *l;
 854
 855	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 856		 le32_to_cpu(sbi->s_es->s_last_orphan));
 857
 858	printk(KERN_ERR "sb_info orphan list:\n");
 859	list_for_each(l, &sbi->s_orphan) {
 860		struct inode *inode = orphan_list_entry(l);
 861		printk(KERN_ERR "  "
 862		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 863		       inode->i_sb->s_id, inode->i_ino, inode,
 864		       inode->i_mode, inode->i_nlink,
 865		       NEXT_ORPHAN(inode));
 866	}
 867}
 868
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 869static void ext4_put_super(struct super_block *sb)
 870{
 871	struct ext4_sb_info *sbi = EXT4_SB(sb);
 872	struct ext4_super_block *es = sbi->s_es;
 873	int i, err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 874
 875	ext4_unregister_li_request(sb);
 876	dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 877
 878	flush_workqueue(sbi->dio_unwritten_wq);
 879	destroy_workqueue(sbi->dio_unwritten_wq);
 
 880
 881	lock_super(sb);
 882	if (sbi->s_journal) {
 
 883		err = jbd2_journal_destroy(sbi->s_journal);
 884		sbi->s_journal = NULL;
 885		if (err < 0)
 886			ext4_abort(sb, "Couldn't clean up the journal");
 
 887	}
 888
 889	del_timer(&sbi->s_err_report);
 
 890	ext4_release_system_zone(sb);
 891	ext4_mb_release(sb);
 892	ext4_ext_release(sb);
 893	ext4_xattr_put_super(sb);
 894
 895	if (!(sb->s_flags & MS_RDONLY)) {
 896		EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 
 897		es->s_state = cpu_to_le16(sbi->s_mount_state);
 898	}
 899	if (sb->s_dirt || !(sb->s_flags & MS_RDONLY))
 900		ext4_commit_super(sb, 1);
 901
 902	if (sbi->s_proc) {
 903		remove_proc_entry("options", sbi->s_proc);
 904		remove_proc_entry(sb->s_id, ext4_proc_root);
 905	}
 906	kobject_del(&sbi->s_kobj);
 907
 908	for (i = 0; i < sbi->s_gdb_count; i++)
 909		brelse(sbi->s_group_desc[i]);
 910	ext4_kvfree(sbi->s_group_desc);
 911	ext4_kvfree(sbi->s_flex_groups);
 912	percpu_counter_destroy(&sbi->s_freeclusters_counter);
 913	percpu_counter_destroy(&sbi->s_freeinodes_counter);
 914	percpu_counter_destroy(&sbi->s_dirs_counter);
 915	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 916	brelse(sbi->s_sbh);
 917#ifdef CONFIG_QUOTA
 918	for (i = 0; i < MAXQUOTAS; i++)
 919		kfree(sbi->s_qf_names[i]);
 920#endif
 921
 922	/* Debugging code just in case the in-memory inode orphan list
 923	 * isn't empty.  The on-disk one can be non-empty if we've
 924	 * detected an error and taken the fs readonly, but the
 925	 * in-memory list had better be clean by this point. */
 926	if (!list_empty(&sbi->s_orphan))
 927		dump_orphan_list(sb, sbi);
 928	J_ASSERT(list_empty(&sbi->s_orphan));
 929
 
 930	invalidate_bdev(sb->s_bdev);
 931	if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 932		/*
 933		 * Invalidate the journal device's buffers.  We don't want them
 934		 * floating about in memory - the physical journal device may
 935		 * hotswapped, and it breaks the `ro-after' testing code.
 936		 */
 937		sync_blockdev(sbi->journal_bdev);
 938		invalidate_bdev(sbi->journal_bdev);
 939		ext4_blkdev_remove(sbi);
 940	}
 941	if (sbi->s_mmp_tsk)
 942		kthread_stop(sbi->s_mmp_tsk);
 
 
 
 
 
 
 
 
 943	sb->s_fs_info = NULL;
 944	/*
 945	 * Now that we are completely done shutting down the
 946	 * superblock, we need to actually destroy the kobject.
 947	 */
 948	unlock_super(sb);
 949	kobject_put(&sbi->s_kobj);
 950	wait_for_completion(&sbi->s_kobj_unregister);
 951	if (sbi->s_chksum_driver)
 952		crypto_free_shash(sbi->s_chksum_driver);
 953	kfree(sbi->s_blockgroup_lock);
 
 
 
 
 
 954	kfree(sbi);
 955}
 956
 957static struct kmem_cache *ext4_inode_cachep;
 958
 959/*
 960 * Called inside transaction, so use GFP_NOFS
 961 */
 962static struct inode *ext4_alloc_inode(struct super_block *sb)
 963{
 964	struct ext4_inode_info *ei;
 965
 966	ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 967	if (!ei)
 968		return NULL;
 969
 970	ei->vfs_inode.i_version = 1;
 971	ei->vfs_inode.i_data.writeback_index = 0;
 972	memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 973	INIT_LIST_HEAD(&ei->i_prealloc_list);
 974	spin_lock_init(&ei->i_prealloc_lock);
 
 
 
 
 
 
 
 975	ei->i_reserved_data_blocks = 0;
 976	ei->i_reserved_meta_blocks = 0;
 977	ei->i_allocated_meta_blocks = 0;
 978	ei->i_da_metadata_calc_len = 0;
 979	ei->i_da_metadata_calc_last_lblock = 0;
 980	spin_lock_init(&(ei->i_block_reservation_lock));
 
 981#ifdef CONFIG_QUOTA
 982	ei->i_reserved_quota = 0;
 
 983#endif
 984	ei->jinode = NULL;
 985	INIT_LIST_HEAD(&ei->i_completed_io_list);
 986	spin_lock_init(&ei->i_completed_io_lock);
 987	ei->cur_aio_dio = NULL;
 988	ei->i_sync_tid = 0;
 989	ei->i_datasync_tid = 0;
 990	atomic_set(&ei->i_ioend_count, 0);
 991	atomic_set(&ei->i_aiodio_unwritten, 0);
 992
 
 993	return &ei->vfs_inode;
 994}
 995
 996static int ext4_drop_inode(struct inode *inode)
 997{
 998	int drop = generic_drop_inode(inode);
 999
 
 
 
1000	trace_ext4_drop_inode(inode, drop);
1001	return drop;
1002}
1003
1004static void ext4_i_callback(struct rcu_head *head)
1005{
1006	struct inode *inode = container_of(head, struct inode, i_rcu);
 
 
 
 
1007	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1008}
1009
1010static void ext4_destroy_inode(struct inode *inode)
1011{
1012	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1013		ext4_msg(inode->i_sb, KERN_ERR,
1014			 "Inode %lu (%p): orphan list check failed!",
1015			 inode->i_ino, EXT4_I(inode));
1016		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1017				EXT4_I(inode), sizeof(struct ext4_inode_info),
1018				true);
1019		dump_stack();
1020	}
1021	call_rcu(&inode->i_rcu, ext4_i_callback);
 
 
 
 
 
 
 
 
 
 
 
1022}
1023
1024static void init_once(void *foo)
1025{
1026	struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1027
1028	INIT_LIST_HEAD(&ei->i_orphan);
1029#ifdef CONFIG_EXT4_FS_XATTR
1030	init_rwsem(&ei->xattr_sem);
1031#endif
1032	init_rwsem(&ei->i_data_sem);
1033	inode_init_once(&ei->vfs_inode);
 
1034}
1035
1036static int init_inodecache(void)
1037{
1038	ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1039					     sizeof(struct ext4_inode_info),
1040					     0, (SLAB_RECLAIM_ACCOUNT|
1041						SLAB_MEM_SPREAD),
1042					     init_once);
 
1043	if (ext4_inode_cachep == NULL)
1044		return -ENOMEM;
1045	return 0;
1046}
1047
1048static void destroy_inodecache(void)
1049{
 
 
 
 
 
1050	kmem_cache_destroy(ext4_inode_cachep);
1051}
1052
1053void ext4_clear_inode(struct inode *inode)
1054{
 
1055	invalidate_inode_buffers(inode);
1056	clear_inode(inode);
1057	dquot_drop(inode);
1058	ext4_discard_preallocations(inode);
 
 
1059	if (EXT4_I(inode)->jinode) {
1060		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1061					       EXT4_I(inode)->jinode);
1062		jbd2_free_inode(EXT4_I(inode)->jinode);
1063		EXT4_I(inode)->jinode = NULL;
1064	}
 
 
1065}
1066
1067static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1068					u64 ino, u32 generation)
1069{
1070	struct inode *inode;
1071
1072	if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1073		return ERR_PTR(-ESTALE);
1074	if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1075		return ERR_PTR(-ESTALE);
1076
1077	/* iget isn't really right if the inode is currently unallocated!!
1078	 *
1079	 * ext4_read_inode will return a bad_inode if the inode had been
1080	 * deleted, so we should be safe.
1081	 *
1082	 * Currently we don't know the generation for parent directory, so
1083	 * a generation of 0 means "accept any"
1084	 */
1085	inode = ext4_iget(sb, ino);
1086	if (IS_ERR(inode))
1087		return ERR_CAST(inode);
1088	if (generation && inode->i_generation != generation) {
1089		iput(inode);
1090		return ERR_PTR(-ESTALE);
1091	}
1092
1093	return inode;
1094}
1095
1096static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1097					int fh_len, int fh_type)
1098{
1099	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1100				    ext4_nfs_get_inode);
1101}
1102
1103static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1104					int fh_len, int fh_type)
1105{
1106	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1107				    ext4_nfs_get_inode);
1108}
1109
1110/*
1111 * Try to release metadata pages (indirect blocks, directories) which are
1112 * mapped via the block device.  Since these pages could have journal heads
1113 * which would prevent try_to_free_buffers() from freeing them, we must use
1114 * jbd2 layer's try_to_free_buffers() function to release them.
1115 */
1116static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1117				 gfp_t wait)
1118{
1119	journal_t *journal = EXT4_SB(sb)->s_journal;
 
 
1120
1121	WARN_ON(PageChecked(page));
1122	if (!page_has_buffers(page))
1123		return 0;
1124	if (journal)
1125		return jbd2_journal_try_to_free_buffers(journal, page,
1126							wait & ~__GFP_WAIT);
1127	return try_to_free_buffers(page);
1128}
1129
1130#ifdef CONFIG_QUOTA
1131#define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1132#define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1133
1134static int ext4_write_dquot(struct dquot *dquot);
1135static int ext4_acquire_dquot(struct dquot *dquot);
1136static int ext4_release_dquot(struct dquot *dquot);
1137static int ext4_mark_dquot_dirty(struct dquot *dquot);
1138static int ext4_write_info(struct super_block *sb, int type);
1139static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1140			 struct path *path);
1141static int ext4_quota_off(struct super_block *sb, int type);
1142static int ext4_quota_on_mount(struct super_block *sb, int type);
1143static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1144			       size_t len, loff_t off);
1145static ssize_t ext4_quota_write(struct super_block *sb, int type,
1146				const char *data, size_t len, loff_t off);
 
 
 
 
 
 
 
1147
1148static const struct dquot_operations ext4_quota_operations = {
1149	.get_reserved_space = ext4_get_reserved_space,
1150	.write_dquot	= ext4_write_dquot,
1151	.acquire_dquot	= ext4_acquire_dquot,
1152	.release_dquot	= ext4_release_dquot,
1153	.mark_dirty	= ext4_mark_dquot_dirty,
1154	.write_info	= ext4_write_info,
1155	.alloc_dquot	= dquot_alloc,
1156	.destroy_dquot	= dquot_destroy,
 
 
 
1157};
1158
1159static const struct quotactl_ops ext4_qctl_operations = {
1160	.quota_on	= ext4_quota_on,
1161	.quota_off	= ext4_quota_off,
1162	.quota_sync	= dquot_quota_sync,
1163	.get_info	= dquot_get_dqinfo,
1164	.set_info	= dquot_set_dqinfo,
1165	.get_dqblk	= dquot_get_dqblk,
1166	.set_dqblk	= dquot_set_dqblk
 
1167};
1168#endif
1169
1170static const struct super_operations ext4_sops = {
1171	.alloc_inode	= ext4_alloc_inode,
 
1172	.destroy_inode	= ext4_destroy_inode,
1173	.write_inode	= ext4_write_inode,
1174	.dirty_inode	= ext4_dirty_inode,
1175	.drop_inode	= ext4_drop_inode,
1176	.evict_inode	= ext4_evict_inode,
1177	.put_super	= ext4_put_super,
1178	.sync_fs	= ext4_sync_fs,
1179	.freeze_fs	= ext4_freeze,
1180	.unfreeze_fs	= ext4_unfreeze,
1181	.statfs		= ext4_statfs,
1182	.remount_fs	= ext4_remount,
1183	.show_options	= ext4_show_options,
1184#ifdef CONFIG_QUOTA
1185	.quota_read	= ext4_quota_read,
1186	.quota_write	= ext4_quota_write,
1187#endif
1188	.bdev_try_to_free_page = bdev_try_to_free_page,
1189};
1190
1191static const struct super_operations ext4_nojournal_sops = {
1192	.alloc_inode	= ext4_alloc_inode,
1193	.destroy_inode	= ext4_destroy_inode,
1194	.write_inode	= ext4_write_inode,
1195	.dirty_inode	= ext4_dirty_inode,
1196	.drop_inode	= ext4_drop_inode,
1197	.evict_inode	= ext4_evict_inode,
1198	.write_super	= ext4_write_super,
1199	.put_super	= ext4_put_super,
1200	.statfs		= ext4_statfs,
1201	.remount_fs	= ext4_remount,
1202	.show_options	= ext4_show_options,
 
1203#ifdef CONFIG_QUOTA
1204	.quota_read	= ext4_quota_read,
1205	.quota_write	= ext4_quota_write,
 
1206#endif
1207	.bdev_try_to_free_page = bdev_try_to_free_page,
1208};
1209
1210static const struct export_operations ext4_export_ops = {
 
1211	.fh_to_dentry = ext4_fh_to_dentry,
1212	.fh_to_parent = ext4_fh_to_parent,
1213	.get_parent = ext4_get_parent,
 
1214};
1215
1216enum {
1217	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1218	Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1219	Opt_nouid32, Opt_debug, Opt_removed,
1220	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1221	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1222	Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1223	Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1224	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1225	Opt_data_err_abort, Opt_data_err_ignore,
1226	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1227	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1228	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1229	Opt_usrquota, Opt_grpquota, Opt_i_version,
1230	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
 
 
1231	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1232	Opt_inode_readahead_blks, Opt_journal_ioprio,
1233	Opt_dioread_nolock, Opt_dioread_lock,
1234	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
 
 
 
 
 
 
1235};
1236
1237static const match_table_t tokens = {
1238	{Opt_bsd_df, "bsddf"},
1239	{Opt_minix_df, "minixdf"},
1240	{Opt_grpid, "grpid"},
1241	{Opt_grpid, "bsdgroups"},
1242	{Opt_nogrpid, "nogrpid"},
1243	{Opt_nogrpid, "sysvgroups"},
1244	{Opt_resgid, "resgid=%u"},
1245	{Opt_resuid, "resuid=%u"},
1246	{Opt_sb, "sb=%u"},
1247	{Opt_err_cont, "errors=continue"},
1248	{Opt_err_panic, "errors=panic"},
1249	{Opt_err_ro, "errors=remount-ro"},
1250	{Opt_nouid32, "nouid32"},
1251	{Opt_debug, "debug"},
1252	{Opt_removed, "oldalloc"},
1253	{Opt_removed, "orlov"},
1254	{Opt_user_xattr, "user_xattr"},
1255	{Opt_nouser_xattr, "nouser_xattr"},
1256	{Opt_acl, "acl"},
1257	{Opt_noacl, "noacl"},
1258	{Opt_noload, "norecovery"},
1259	{Opt_noload, "noload"},
1260	{Opt_removed, "nobh"},
1261	{Opt_removed, "bh"},
1262	{Opt_commit, "commit=%u"},
1263	{Opt_min_batch_time, "min_batch_time=%u"},
1264	{Opt_max_batch_time, "max_batch_time=%u"},
1265	{Opt_journal_dev, "journal_dev=%u"},
1266	{Opt_journal_checksum, "journal_checksum"},
1267	{Opt_journal_async_commit, "journal_async_commit"},
1268	{Opt_abort, "abort"},
1269	{Opt_data_journal, "data=journal"},
1270	{Opt_data_ordered, "data=ordered"},
1271	{Opt_data_writeback, "data=writeback"},
1272	{Opt_data_err_abort, "data_err=abort"},
1273	{Opt_data_err_ignore, "data_err=ignore"},
1274	{Opt_offusrjquota, "usrjquota="},
1275	{Opt_usrjquota, "usrjquota=%s"},
1276	{Opt_offgrpjquota, "grpjquota="},
1277	{Opt_grpjquota, "grpjquota=%s"},
1278	{Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1279	{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1280	{Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1281	{Opt_grpquota, "grpquota"},
1282	{Opt_noquota, "noquota"},
1283	{Opt_quota, "quota"},
1284	{Opt_usrquota, "usrquota"},
1285	{Opt_barrier, "barrier=%u"},
1286	{Opt_barrier, "barrier"},
1287	{Opt_nobarrier, "nobarrier"},
1288	{Opt_i_version, "i_version"},
1289	{Opt_stripe, "stripe=%u"},
1290	{Opt_delalloc, "delalloc"},
1291	{Opt_nodelalloc, "nodelalloc"},
1292	{Opt_mblk_io_submit, "mblk_io_submit"},
1293	{Opt_nomblk_io_submit, "nomblk_io_submit"},
1294	{Opt_block_validity, "block_validity"},
1295	{Opt_noblock_validity, "noblock_validity"},
1296	{Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1297	{Opt_journal_ioprio, "journal_ioprio=%u"},
1298	{Opt_auto_da_alloc, "auto_da_alloc=%u"},
1299	{Opt_auto_da_alloc, "auto_da_alloc"},
1300	{Opt_noauto_da_alloc, "noauto_da_alloc"},
1301	{Opt_dioread_nolock, "dioread_nolock"},
1302	{Opt_dioread_lock, "dioread_lock"},
1303	{Opt_discard, "discard"},
1304	{Opt_nodiscard, "nodiscard"},
1305	{Opt_init_itable, "init_itable=%u"},
1306	{Opt_init_itable, "init_itable"},
1307	{Opt_noinit_itable, "noinit_itable"},
1308	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
1309	{Opt_removed, "nocheck"},	/* mount option from ext2/3 */
1310	{Opt_removed, "reservation"},	/* mount option from ext2/3 */
1311	{Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1312	{Opt_removed, "journal=%u"},	/* mount option from ext2/3 */
1313	{Opt_err, NULL},
1314};
1315
1316static ext4_fsblk_t get_sb_block(void **data)
1317{
1318	ext4_fsblk_t	sb_block;
1319	char		*options = (char *) *data;
1320
1321	if (!options || strncmp(options, "sb=", 3) != 0)
1322		return 1;	/* Default location */
1323
1324	options += 3;
1325	/* TODO: use simple_strtoll with >32bit ext4 */
1326	sb_block = simple_strtoul(options, &options, 0);
1327	if (*options && *options != ',') {
1328		printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1329		       (char *) *data);
1330		return 1;
1331	}
1332	if (*options == ',')
1333		options++;
1334	*data = (void *) options;
1335
1336	return sb_block;
1337}
1338
1339#define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1340static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1341	"Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1342
1343#ifdef CONFIG_QUOTA
1344static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1345{
1346	struct ext4_sb_info *sbi = EXT4_SB(sb);
1347	char *qname;
1348
1349	if (sb_any_quota_loaded(sb) &&
1350		!sbi->s_qf_names[qtype]) {
1351		ext4_msg(sb, KERN_ERR,
1352			"Cannot change journaled "
1353			"quota options when quota turned on");
1354		return -1;
1355	}
1356	qname = match_strdup(args);
1357	if (!qname) {
1358		ext4_msg(sb, KERN_ERR,
1359			"Not enough memory for storing quotafile name");
1360		return -1;
1361	}
1362	if (sbi->s_qf_names[qtype] &&
1363		strcmp(sbi->s_qf_names[qtype], qname)) {
1364		ext4_msg(sb, KERN_ERR,
1365			"%s quota file already specified", QTYPE2NAME(qtype));
1366		kfree(qname);
1367		return -1;
1368	}
1369	sbi->s_qf_names[qtype] = qname;
1370	if (strchr(sbi->s_qf_names[qtype], '/')) {
1371		ext4_msg(sb, KERN_ERR,
1372			"quotafile must be on filesystem root");
1373		kfree(sbi->s_qf_names[qtype]);
1374		sbi->s_qf_names[qtype] = NULL;
1375		return -1;
1376	}
1377	set_opt(sb, QUOTA);
1378	return 1;
1379}
1380
1381static int clear_qf_name(struct super_block *sb, int qtype)
1382{
 
 
 
 
1383
1384	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
 
 
 
 
1385
1386	if (sb_any_quota_loaded(sb) &&
1387		sbi->s_qf_names[qtype]) {
1388		ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1389			" when quota turned on");
1390		return -1;
1391	}
1392	/*
1393	 * The space will be released later when all options are confirmed
1394	 * to be correct
1395	 */
1396	sbi->s_qf_names[qtype] = NULL;
1397	return 1;
1398}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1399#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1400
1401#define MOPT_SET	0x0001
1402#define MOPT_CLEAR	0x0002
1403#define MOPT_NOSUPPORT	0x0004
1404#define MOPT_EXPLICIT	0x0008
1405#define MOPT_CLEAR_ERR	0x0010
1406#define MOPT_GTE0	0x0020
1407#ifdef CONFIG_QUOTA
1408#define MOPT_Q		0
1409#define MOPT_QFMT	0x0040
1410#else
1411#define MOPT_Q		MOPT_NOSUPPORT
1412#define MOPT_QFMT	MOPT_NOSUPPORT
1413#endif
1414#define MOPT_DATAJ	0x0080
 
 
 
 
1415
1416static const struct mount_opts {
1417	int	token;
1418	int	mount_opt;
1419	int	flags;
1420} ext4_mount_opts[] = {
1421	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1422	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1423	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1424	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1425	{Opt_mblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_SET},
1426	{Opt_nomblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_CLEAR},
1427	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1428	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1429	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
1430	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
 
 
1431	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1432	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1433	{Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
1434	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
1435	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
 
 
 
 
 
 
 
 
1436	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1437				    EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
1438	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
1439	{Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1440	{Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1441	{Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1442	{Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
1443	{Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
1444	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1445	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1446	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1447	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1448	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1449	{Opt_commit, 0, MOPT_GTE0},
1450	{Opt_max_batch_time, 0, MOPT_GTE0},
1451	{Opt_min_batch_time, 0, MOPT_GTE0},
1452	{Opt_inode_readahead_blks, 0, MOPT_GTE0},
1453	{Opt_init_itable, 0, MOPT_GTE0},
1454	{Opt_stripe, 0, MOPT_GTE0},
1455	{Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
1456	{Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
1457	{Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
1458#ifdef CONFIG_EXT4_FS_XATTR
1459	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1460	{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1461#else
1462	{Opt_user_xattr, 0, MOPT_NOSUPPORT},
1463	{Opt_nouser_xattr, 0, MOPT_NOSUPPORT},
1464#endif
1465#ifdef CONFIG_EXT4_FS_POSIX_ACL
1466	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1467	{Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1468#else
1469	{Opt_acl, 0, MOPT_NOSUPPORT},
1470	{Opt_noacl, 0, MOPT_NOSUPPORT},
1471#endif
1472	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1473	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1474	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1475	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1476							MOPT_SET | MOPT_Q},
1477	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1478							MOPT_SET | MOPT_Q},
 
 
1479	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1480		       EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
 
1481	{Opt_usrjquota, 0, MOPT_Q},
1482	{Opt_grpjquota, 0, MOPT_Q},
1483	{Opt_offusrjquota, 0, MOPT_Q},
1484	{Opt_offgrpjquota, 0, MOPT_Q},
1485	{Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1486	{Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1487	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
 
 
 
 
1488	{Opt_err, 0, 0}
1489};
1490
1491static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1492			    substring_t *args, unsigned long *journal_devnum,
1493			    unsigned int *journal_ioprio, int is_remount)
 
 
 
 
 
 
 
 
1494{
1495	struct ext4_sb_info *sbi = EXT4_SB(sb);
1496	const struct mount_opts *m;
1497	kuid_t uid;
1498	kgid_t gid;
1499	int arg = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1500
1501#ifdef CONFIG_QUOTA
1502	if (token == Opt_usrjquota)
1503		return set_qf_name(sb, USRQUOTA, &args[0]);
1504	else if (token == Opt_grpjquota)
1505		return set_qf_name(sb, GRPQUOTA, &args[0]);
1506	else if (token == Opt_offusrjquota)
1507		return clear_qf_name(sb, USRQUOTA);
1508	else if (token == Opt_offgrpjquota)
1509		return clear_qf_name(sb, GRPQUOTA);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1510#endif
1511	if (args->from && match_int(args, &arg))
1512		return -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1513	switch (token) {
1514	case Opt_noacl:
1515	case Opt_nouser_xattr:
1516		ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1517		break;
 
 
 
 
 
 
 
 
1518	case Opt_sb:
1519		return 1;	/* handled by get_sb_block() */
 
 
 
 
 
 
 
1520	case Opt_removed:
1521		ext4_msg(sb, KERN_WARNING,
1522			 "Ignoring removed %s option", opt);
1523		return 1;
1524	case Opt_resuid:
1525		uid = make_kuid(current_user_ns(), arg);
1526		if (!uid_valid(uid)) {
1527			ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1528			return -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1529		}
1530		sbi->s_resuid = uid;
1531		return 1;
1532	case Opt_resgid:
1533		gid = make_kgid(current_user_ns(), arg);
1534		if (!gid_valid(gid)) {
1535			ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1536			return -1;
 
1537		}
1538		sbi->s_resgid = gid;
1539		return 1;
1540	case Opt_abort:
1541		sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1542		return 1;
1543	case Opt_i_version:
1544		sb->s_flags |= MS_I_VERSION;
1545		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1546	case Opt_journal_dev:
1547		if (is_remount) {
1548			ext4_msg(sb, KERN_ERR,
1549				 "Cannot specify journal on remount");
1550			return -1;
1551		}
1552		*journal_devnum = arg;
1553		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1554	case Opt_journal_ioprio:
1555		if (arg < 0 || arg > 7)
1556			return -1;
1557		*journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1558		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1559	}
1560
1561	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1562		if (token != m->token)
1563			continue;
1564		if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1565			return -1;
1566		if (m->flags & MOPT_EXPLICIT)
1567			set_opt2(sb, EXPLICIT_DELALLOC);
1568		if (m->flags & MOPT_CLEAR_ERR)
1569			clear_opt(sb, ERRORS_MASK);
1570		if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1571			ext4_msg(sb, KERN_ERR, "Cannot change quota "
1572				 "options when quota turned on");
1573			return -1;
1574		}
1575
1576		if (m->flags & MOPT_NOSUPPORT) {
1577			ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1578		} else if (token == Opt_commit) {
1579			if (arg == 0)
1580				arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1581			sbi->s_commit_interval = HZ * arg;
1582		} else if (token == Opt_max_batch_time) {
1583			if (arg == 0)
1584				arg = EXT4_DEF_MAX_BATCH_TIME;
1585			sbi->s_max_batch_time = arg;
1586		} else if (token == Opt_min_batch_time) {
1587			sbi->s_min_batch_time = arg;
1588		} else if (token == Opt_inode_readahead_blks) {
1589			if (arg > (1 << 30))
1590				return -1;
1591			if (arg && !is_power_of_2(arg)) {
1592				ext4_msg(sb, KERN_ERR,
1593					 "EXT4-fs: inode_readahead_blks"
1594					 " must be a power of 2");
1595				return -1;
1596			}
1597			sbi->s_inode_readahead_blks = arg;
1598		} else if (token == Opt_init_itable) {
1599			set_opt(sb, INIT_INODE_TABLE);
1600			if (!args->from)
1601				arg = EXT4_DEF_LI_WAIT_MULT;
1602			sbi->s_li_wait_mult = arg;
1603		} else if (token == Opt_stripe) {
1604			sbi->s_stripe = arg;
1605		} else if (m->flags & MOPT_DATAJ) {
1606			if (is_remount) {
1607				if (!sbi->s_journal)
1608					ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1609				else if (test_opt(sb, DATA_FLAGS) !=
1610					 m->mount_opt) {
1611					ext4_msg(sb, KERN_ERR,
1612					 "Cannot change data mode on remount");
1613					return -1;
1614				}
1615			} else {
1616				clear_opt(sb, DATA_FLAGS);
1617				sbi->s_mount_opt |= m->mount_opt;
1618			}
1619#ifdef CONFIG_QUOTA
1620		} else if (m->flags & MOPT_QFMT) {
1621			if (sb_any_quota_loaded(sb) &&
1622			    sbi->s_jquota_fmt != m->mount_opt) {
1623				ext4_msg(sb, KERN_ERR, "Cannot "
1624					 "change journaled quota options "
1625					 "when quota turned on");
1626				return -1;
1627			}
1628			sbi->s_jquota_fmt = m->mount_opt;
1629#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
1630		} else {
1631			if (!args->from)
1632				arg = 1;
1633			if (m->flags & MOPT_CLEAR)
1634				arg = !arg;
1635			else if (unlikely(!(m->flags & MOPT_SET))) {
1636				ext4_msg(sb, KERN_WARNING,
1637					 "buggy handling of option %s", opt);
1638				WARN_ON(1);
1639				return -1;
1640			}
1641			if (arg != 0)
1642				sbi->s_mount_opt |= m->mount_opt;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1643			else
1644				sbi->s_mount_opt &= ~m->mount_opt;
 
 
 
 
 
1645		}
1646		return 1;
1647	}
1648	ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1649		 "or missing value", opt);
1650	return -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1651}
1652
1653static int parse_options(char *options, struct super_block *sb,
1654			 unsigned long *journal_devnum,
1655			 unsigned int *journal_ioprio,
1656			 int is_remount)
1657{
1658#ifdef CONFIG_QUOTA
 
 
1659	struct ext4_sb_info *sbi = EXT4_SB(sb);
1660#endif
1661	char *p;
1662	substring_t args[MAX_OPT_ARGS];
1663	int token;
1664
1665	if (!options)
1666		return 1;
1667
1668	while ((p = strsep(&options, ",")) != NULL) {
1669		if (!*p)
1670			continue;
1671		/*
1672		 * Initialize args struct so we know whether arg was
1673		 * found; some options take optional arguments.
1674		 */
1675		args[0].to = args[0].from = 0;
1676		token = match_token(p, tokens, args);
1677		if (handle_mount_opt(sb, p, token, args, journal_devnum,
1678				     journal_ioprio, is_remount) < 0)
1679			return 0;
 
 
1680	}
 
 
 
 
 
 
 
 
 
 
 
 
1681#ifdef CONFIG_QUOTA
1682	if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1683		if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1684			clear_opt(sb, USRQUOTA);
1685
1686		if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1687			clear_opt(sb, GRPQUOTA);
1688
1689		if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1690			ext4_msg(sb, KERN_ERR, "old and new quota "
1691					"format mixing");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1692			return 0;
1693		}
 
1694
1695		if (!sbi->s_jquota_fmt) {
1696			ext4_msg(sb, KERN_ERR, "journaled quota format "
1697					"not specified");
 
 
 
1698			return 0;
1699		}
1700	} else {
1701		if (sbi->s_jquota_fmt) {
1702			ext4_msg(sb, KERN_ERR, "journaled quota format "
1703					"specified with no journaling "
1704					"enabled");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1705			return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1706		}
1707	}
1708#endif
1709	return 1;
1710}
1711
1712static inline void ext4_show_quota_options(struct seq_file *seq,
1713					   struct super_block *sb)
1714{
1715#if defined(CONFIG_QUOTA)
1716	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
1717
1718	if (sbi->s_jquota_fmt) {
1719		char *fmtname = "";
1720
1721		switch (sbi->s_jquota_fmt) {
1722		case QFMT_VFS_OLD:
1723			fmtname = "vfsold";
1724			break;
1725		case QFMT_VFS_V0:
1726			fmtname = "vfsv0";
1727			break;
1728		case QFMT_VFS_V1:
1729			fmtname = "vfsv1";
1730			break;
1731		}
1732		seq_printf(seq, ",jqfmt=%s", fmtname);
1733	}
1734
1735	if (sbi->s_qf_names[USRQUOTA])
1736		seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1737
1738	if (sbi->s_qf_names[GRPQUOTA])
1739		seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1740
1741	if (test_opt(sb, USRQUOTA))
1742		seq_puts(seq, ",usrquota");
1743
1744	if (test_opt(sb, GRPQUOTA))
1745		seq_puts(seq, ",grpquota");
1746#endif
1747}
1748
1749static const char *token2str(int token)
1750{
1751	static const struct match_token *t;
1752
1753	for (t = tokens; t->token != Opt_err; t++)
1754		if (t->token == token && !strchr(t->pattern, '='))
1755			break;
1756	return t->pattern;
1757}
1758
1759/*
1760 * Show an option if
1761 *  - it's set to a non-default value OR
1762 *  - if the per-sb default is different from the global default
1763 */
1764static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1765			      int nodefs)
1766{
1767	struct ext4_sb_info *sbi = EXT4_SB(sb);
1768	struct ext4_super_block *es = sbi->s_es;
1769	int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1770	const struct mount_opts *m;
1771	char sep = nodefs ? '\n' : ',';
1772
1773#define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1774#define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1775
1776	if (sbi->s_sb_block != 1)
1777		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1778
1779	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1780		int want_set = m->flags & MOPT_SET;
 
 
 
1781		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1782		    (m->flags & MOPT_CLEAR_ERR))
 
 
 
 
 
 
 
 
 
 
 
1783			continue;
1784		if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1785			continue; /* skip if same as the default */
1786		if ((want_set &&
1787		     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1788		    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1789			continue; /* select Opt_noFoo vs Opt_Foo */
1790		SEQ_OPTS_PRINT("%s", token2str(m->token));
1791	}
1792
1793	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1794	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1795		SEQ_OPTS_PRINT("resuid=%u",
1796				from_kuid_munged(&init_user_ns, sbi->s_resuid));
1797	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1798	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1799		SEQ_OPTS_PRINT("resgid=%u",
1800				from_kgid_munged(&init_user_ns, sbi->s_resgid));
1801	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1802	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1803		SEQ_OPTS_PUTS("errors=remount-ro");
1804	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1805		SEQ_OPTS_PUTS("errors=continue");
1806	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1807		SEQ_OPTS_PUTS("errors=panic");
1808	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1809		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1810	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1811		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1812	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1813		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1814	if (sb->s_flags & MS_I_VERSION)
1815		SEQ_OPTS_PUTS("i_version");
1816	if (nodefs || sbi->s_stripe)
1817		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1818	if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
 
1819		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1820			SEQ_OPTS_PUTS("data=journal");
1821		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1822			SEQ_OPTS_PUTS("data=ordered");
1823		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1824			SEQ_OPTS_PUTS("data=writeback");
1825	}
1826	if (nodefs ||
1827	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1828		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1829			       sbi->s_inode_readahead_blks);
1830
1831	if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1832		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1833		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1834
1835	ext4_show_quota_options(seq, sb);
1836	return 0;
1837}
1838
1839static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1840{
1841	return _ext4_show_options(seq, root->d_sb, 0);
1842}
1843
1844static int options_seq_show(struct seq_file *seq, void *offset)
1845{
1846	struct super_block *sb = seq->private;
1847	int rc;
1848
1849	seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1850	rc = _ext4_show_options(seq, sb, 1);
1851	seq_puts(seq, "\n");
1852	return rc;
1853}
1854
1855static int options_open_fs(struct inode *inode, struct file *file)
1856{
1857	return single_open(file, options_seq_show, PDE(inode)->data);
1858}
1859
1860static const struct file_operations ext4_seq_options_fops = {
1861	.owner = THIS_MODULE,
1862	.open = options_open_fs,
1863	.read = seq_read,
1864	.llseek = seq_lseek,
1865	.release = single_release,
1866};
1867
1868static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1869			    int read_only)
1870{
1871	struct ext4_sb_info *sbi = EXT4_SB(sb);
1872	int res = 0;
1873
1874	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1875		ext4_msg(sb, KERN_ERR, "revision level too high, "
1876			 "forcing read-only mode");
1877		res = MS_RDONLY;
 
1878	}
1879	if (read_only)
1880		goto done;
1881	if (!(sbi->s_mount_state & EXT4_VALID_FS))
1882		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1883			 "running e2fsck is recommended");
1884	else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1885		ext4_msg(sb, KERN_WARNING,
1886			 "warning: mounting fs with errors, "
1887			 "running e2fsck is recommended");
1888	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1889		 le16_to_cpu(es->s_mnt_count) >=
1890		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1891		ext4_msg(sb, KERN_WARNING,
1892			 "warning: maximal mount count reached, "
1893			 "running e2fsck is recommended");
1894	else if (le32_to_cpu(es->s_checkinterval) &&
1895		(le32_to_cpu(es->s_lastcheck) +
1896			le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1897		ext4_msg(sb, KERN_WARNING,
1898			 "warning: checktime reached, "
1899			 "running e2fsck is recommended");
1900	if (!sbi->s_journal)
1901		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1902	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1903		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1904	le16_add_cpu(&es->s_mnt_count, 1);
1905	es->s_mtime = cpu_to_le32(get_seconds());
1906	ext4_update_dynamic_rev(sb);
1907	if (sbi->s_journal)
1908		EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 
 
1909
1910	ext4_commit_super(sb, 1);
1911done:
1912	if (test_opt(sb, DEBUG))
1913		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1914				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1915			sb->s_blocksize,
1916			sbi->s_groups_count,
1917			EXT4_BLOCKS_PER_GROUP(sb),
1918			EXT4_INODES_PER_GROUP(sb),
1919			sbi->s_mount_opt, sbi->s_mount_opt2);
 
 
1920
1921	cleancache_init_fs(sb);
1922	return res;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1923}
1924
1925static int ext4_fill_flex_info(struct super_block *sb)
1926{
1927	struct ext4_sb_info *sbi = EXT4_SB(sb);
1928	struct ext4_group_desc *gdp = NULL;
1929	ext4_group_t flex_group_count;
1930	ext4_group_t flex_group;
1931	unsigned int groups_per_flex = 0;
1932	size_t size;
1933	int i;
1934
1935	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1936	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1937		sbi->s_log_groups_per_flex = 0;
1938		return 1;
1939	}
1940	groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1941
1942	/* We allocate both existing and potentially added groups */
1943	flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1944			((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1945			      EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1946	size = flex_group_count * sizeof(struct flex_groups);
1947	sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
1948	if (sbi->s_flex_groups == NULL) {
1949		ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
1950			 flex_group_count);
1951		goto failed;
1952	}
1953
1954	for (i = 0; i < sbi->s_groups_count; i++) {
1955		gdp = ext4_get_group_desc(sb, i, NULL);
1956
1957		flex_group = ext4_flex_group(sbi, i);
1958		atomic_add(ext4_free_inodes_count(sb, gdp),
1959			   &sbi->s_flex_groups[flex_group].free_inodes);
1960		atomic_add(ext4_free_group_clusters(sb, gdp),
1961			   &sbi->s_flex_groups[flex_group].free_clusters);
1962		atomic_add(ext4_used_dirs_count(sb, gdp),
1963			   &sbi->s_flex_groups[flex_group].used_dirs);
1964	}
1965
1966	return 1;
1967failed:
1968	return 0;
1969}
1970
1971static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1972				   struct ext4_group_desc *gdp)
1973{
1974	int offset;
1975	__u16 crc = 0;
1976	__le32 le_group = cpu_to_le32(block_group);
 
1977
1978	if ((sbi->s_es->s_feature_ro_compat &
1979	     cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
1980		/* Use new metadata_csum algorithm */
1981		__u16 old_csum;
1982		__u32 csum32;
 
1983
1984		old_csum = gdp->bg_checksum;
1985		gdp->bg_checksum = 0;
1986		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
1987				     sizeof(le_group));
1988		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
1989				     sbi->s_desc_size);
1990		gdp->bg_checksum = old_csum;
 
 
 
 
1991
1992		crc = csum32 & 0xFFFF;
1993		goto out;
1994	}
1995
1996	/* old crc16 code */
1997	offset = offsetof(struct ext4_group_desc, bg_checksum);
 
1998
1999	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2000	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2001	crc = crc16(crc, (__u8 *)gdp, offset);
2002	offset += sizeof(gdp->bg_checksum); /* skip checksum */
2003	/* for checksum of struct ext4_group_desc do the rest...*/
2004	if ((sbi->s_es->s_feature_incompat &
2005	     cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2006	    offset < le16_to_cpu(sbi->s_es->s_desc_size))
2007		crc = crc16(crc, (__u8 *)gdp + offset,
2008			    le16_to_cpu(sbi->s_es->s_desc_size) -
2009				offset);
2010
2011out:
2012	return cpu_to_le16(crc);
2013}
2014
2015int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2016				struct ext4_group_desc *gdp)
2017{
2018	if (ext4_has_group_desc_csum(sb) &&
2019	    (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2020						      block_group, gdp)))
2021		return 0;
2022
2023	return 1;
2024}
2025
2026void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2027			      struct ext4_group_desc *gdp)
2028{
2029	if (!ext4_has_group_desc_csum(sb))
2030		return;
2031	gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2032}
2033
2034/* Called at mount-time, super-block is locked */
2035static int ext4_check_descriptors(struct super_block *sb,
 
2036				  ext4_group_t *first_not_zeroed)
2037{
2038	struct ext4_sb_info *sbi = EXT4_SB(sb);
2039	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2040	ext4_fsblk_t last_block;
 
2041	ext4_fsblk_t block_bitmap;
2042	ext4_fsblk_t inode_bitmap;
2043	ext4_fsblk_t inode_table;
2044	int flexbg_flag = 0;
2045	ext4_group_t i, grp = sbi->s_groups_count;
2046
2047	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2048		flexbg_flag = 1;
2049
2050	ext4_debug("Checking group descriptors");
2051
2052	for (i = 0; i < sbi->s_groups_count; i++) {
2053		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2054
2055		if (i == sbi->s_groups_count - 1 || flexbg_flag)
2056			last_block = ext4_blocks_count(sbi->s_es) - 1;
2057		else
2058			last_block = first_block +
2059				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
2060
2061		if ((grp == sbi->s_groups_count) &&
2062		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2063			grp = i;
2064
2065		block_bitmap = ext4_block_bitmap(sb, gdp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2066		if (block_bitmap < first_block || block_bitmap > last_block) {
2067			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2068			       "Block bitmap for group %u not in group "
2069			       "(block %llu)!", i, block_bitmap);
2070			return 0;
2071		}
2072		inode_bitmap = ext4_inode_bitmap(sb, gdp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2073		if (inode_bitmap < first_block || inode_bitmap > last_block) {
2074			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2075			       "Inode bitmap for group %u not in group "
2076			       "(block %llu)!", i, inode_bitmap);
2077			return 0;
2078		}
2079		inode_table = ext4_inode_table(sb, gdp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2080		if (inode_table < first_block ||
2081		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
2082			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2083			       "Inode table for group %u not in group "
2084			       "(block %llu)!", i, inode_table);
2085			return 0;
2086		}
2087		ext4_lock_group(sb, i);
2088		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2089			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2090				 "Checksum for group %u failed (%u!=%u)",
2091				 i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2092				     gdp)), le16_to_cpu(gdp->bg_checksum));
2093			if (!(sb->s_flags & MS_RDONLY)) {
2094				ext4_unlock_group(sb, i);
2095				return 0;
2096			}
2097		}
2098		ext4_unlock_group(sb, i);
2099		if (!flexbg_flag)
2100			first_block += EXT4_BLOCKS_PER_GROUP(sb);
2101	}
2102	if (NULL != first_not_zeroed)
2103		*first_not_zeroed = grp;
2104
2105	ext4_free_blocks_count_set(sbi->s_es,
2106				   EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2107	sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2108	return 1;
2109}
2110
2111/* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2112 * the superblock) which were deleted from all directories, but held open by
2113 * a process at the time of a crash.  We walk the list and try to delete these
2114 * inodes at recovery time (only with a read-write filesystem).
2115 *
2116 * In order to keep the orphan inode chain consistent during traversal (in
2117 * case of crash during recovery), we link each inode into the superblock
2118 * orphan list_head and handle it the same way as an inode deletion during
2119 * normal operation (which journals the operations for us).
2120 *
2121 * We only do an iget() and an iput() on each inode, which is very safe if we
2122 * accidentally point at an in-use or already deleted inode.  The worst that
2123 * can happen in this case is that we get a "bit already cleared" message from
2124 * ext4_free_inode().  The only reason we would point at a wrong inode is if
2125 * e2fsck was run on this filesystem, and it must have already done the orphan
2126 * inode cleanup for us, so we can safely abort without any further action.
2127 */
2128static void ext4_orphan_cleanup(struct super_block *sb,
2129				struct ext4_super_block *es)
2130{
2131	unsigned int s_flags = sb->s_flags;
2132	int nr_orphans = 0, nr_truncates = 0;
2133#ifdef CONFIG_QUOTA
2134	int i;
2135#endif
2136	if (!es->s_last_orphan) {
2137		jbd_debug(4, "no orphan inodes to clean up\n");
2138		return;
2139	}
2140
2141	if (bdev_read_only(sb->s_bdev)) {
2142		ext4_msg(sb, KERN_ERR, "write access "
2143			"unavailable, skipping orphan cleanup");
2144		return;
2145	}
2146
2147	/* Check if feature set would not allow a r/w mount */
2148	if (!ext4_feature_set_ok(sb, 0)) {
2149		ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2150			 "unknown ROCOMPAT features");
2151		return;
2152	}
2153
2154	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2155		if (es->s_last_orphan)
2156			jbd_debug(1, "Errors on filesystem, "
2157				  "clearing orphan list.\n");
2158		es->s_last_orphan = 0;
2159		jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2160		return;
2161	}
2162
2163	if (s_flags & MS_RDONLY) {
2164		ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2165		sb->s_flags &= ~MS_RDONLY;
2166	}
2167#ifdef CONFIG_QUOTA
2168	/* Needed for iput() to work correctly and not trash data */
2169	sb->s_flags |= MS_ACTIVE;
2170	/* Turn on quotas so that they are updated correctly */
2171	for (i = 0; i < MAXQUOTAS; i++) {
2172		if (EXT4_SB(sb)->s_qf_names[i]) {
2173			int ret = ext4_quota_on_mount(sb, i);
2174			if (ret < 0)
2175				ext4_msg(sb, KERN_ERR,
2176					"Cannot turn on journaled "
2177					"quota: error %d", ret);
2178		}
2179	}
2180#endif
2181
2182	while (es->s_last_orphan) {
2183		struct inode *inode;
2184
2185		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2186		if (IS_ERR(inode)) {
2187			es->s_last_orphan = 0;
2188			break;
2189		}
2190
2191		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2192		dquot_initialize(inode);
2193		if (inode->i_nlink) {
2194			ext4_msg(sb, KERN_DEBUG,
2195				"%s: truncating inode %lu to %lld bytes",
2196				__func__, inode->i_ino, inode->i_size);
2197			jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2198				  inode->i_ino, inode->i_size);
2199			ext4_truncate(inode);
2200			nr_truncates++;
2201		} else {
2202			ext4_msg(sb, KERN_DEBUG,
2203				"%s: deleting unreferenced inode %lu",
2204				__func__, inode->i_ino);
2205			jbd_debug(2, "deleting unreferenced inode %lu\n",
2206				  inode->i_ino);
2207			nr_orphans++;
2208		}
2209		iput(inode);  /* The delete magic happens here! */
2210	}
2211
2212#define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2213
2214	if (nr_orphans)
2215		ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2216		       PLURAL(nr_orphans));
2217	if (nr_truncates)
2218		ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2219		       PLURAL(nr_truncates));
2220#ifdef CONFIG_QUOTA
2221	/* Turn quotas off */
2222	for (i = 0; i < MAXQUOTAS; i++) {
2223		if (sb_dqopt(sb)->files[i])
2224			dquot_quota_off(sb, i);
2225	}
2226#endif
2227	sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2228}
2229
2230/*
2231 * Maximal extent format file size.
2232 * Resulting logical blkno at s_maxbytes must fit in our on-disk
2233 * extent format containers, within a sector_t, and within i_blocks
2234 * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2235 * so that won't be a limiting factor.
2236 *
2237 * However there is other limiting factor. We do store extents in the form
2238 * of starting block and length, hence the resulting length of the extent
2239 * covering maximum file size must fit into on-disk format containers as
2240 * well. Given that length is always by 1 unit bigger than max unit (because
2241 * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2242 *
2243 * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2244 */
2245static loff_t ext4_max_size(int blkbits, int has_huge_files)
2246{
2247	loff_t res;
2248	loff_t upper_limit = MAX_LFS_FILESIZE;
2249
2250	/* small i_blocks in vfs inode? */
2251	if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2252		/*
2253		 * CONFIG_LBDAF is not enabled implies the inode
2254		 * i_block represent total blocks in 512 bytes
2255		 * 32 == size of vfs inode i_blocks * 8
2256		 */
2257		upper_limit = (1LL << 32) - 1;
2258
2259		/* total blocks in file system block size */
2260		upper_limit >>= (blkbits - 9);
2261		upper_limit <<= blkbits;
2262	}
2263
2264	/*
2265	 * 32-bit extent-start container, ee_block. We lower the maxbytes
2266	 * by one fs block, so ee_len can cover the extent of maximum file
2267	 * size
2268	 */
2269	res = (1LL << 32) - 1;
2270	res <<= blkbits;
2271
2272	/* Sanity check against vm- & vfs- imposed limits */
2273	if (res > upper_limit)
2274		res = upper_limit;
2275
2276	return res;
2277}
2278
2279/*
2280 * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2281 * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2282 * We need to be 1 filesystem block less than the 2^48 sector limit.
2283 */
2284static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2285{
2286	loff_t res = EXT4_NDIR_BLOCKS;
2287	int meta_blocks;
2288	loff_t upper_limit;
2289	/* This is calculated to be the largest file size for a dense, block
 
 
2290	 * mapped file such that the file's total number of 512-byte sectors,
2291	 * including data and all indirect blocks, does not exceed (2^48 - 1).
2292	 *
2293	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2294	 * number of 512-byte sectors of the file.
2295	 */
2296
2297	if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2298		/*
2299		 * !has_huge_files or CONFIG_LBDAF not enabled implies that
2300		 * the inode i_block field represents total file blocks in
2301		 * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2302		 */
2303		upper_limit = (1LL << 32) - 1;
2304
2305		/* total blocks in file system block size */
2306		upper_limit >>= (bits - 9);
2307
2308	} else {
2309		/*
2310		 * We use 48 bit ext4_inode i_blocks
2311		 * With EXT4_HUGE_FILE_FL set the i_blocks
2312		 * represent total number of blocks in
2313		 * file system block size
2314		 */
2315		upper_limit = (1LL << 48) - 1;
2316
2317	}
2318
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2319	/* indirect blocks */
2320	meta_blocks = 1;
 
2321	/* double indirect blocks */
2322	meta_blocks += 1 + (1LL << (bits-2));
2323	/* tripple indirect blocks */
2324	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2325
2326	upper_limit -= meta_blocks;
2327	upper_limit <<= bits;
2328
2329	res += 1LL << (bits-2);
2330	res += 1LL << (2*(bits-2));
2331	res += 1LL << (3*(bits-2));
 
 
2332	res <<= bits;
2333	if (res > upper_limit)
2334		res = upper_limit;
2335
2336	if (res > MAX_LFS_FILESIZE)
2337		res = MAX_LFS_FILESIZE;
2338
2339	return res;
2340}
2341
2342static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2343				   ext4_fsblk_t logical_sb_block, int nr)
2344{
2345	struct ext4_sb_info *sbi = EXT4_SB(sb);
2346	ext4_group_t bg, first_meta_bg;
2347	int has_super = 0;
2348
2349	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2350
2351	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2352	    nr < first_meta_bg)
2353		return logical_sb_block + nr + 1;
2354	bg = sbi->s_desc_per_block * nr;
2355	if (ext4_bg_has_super(sb, bg))
2356		has_super = 1;
2357
 
 
 
 
 
 
 
 
 
 
2358	return (has_super + ext4_group_first_block_no(sb, bg));
2359}
2360
2361/**
2362 * ext4_get_stripe_size: Get the stripe size.
2363 * @sbi: In memory super block info
2364 *
2365 * If we have specified it via mount option, then
2366 * use the mount option value. If the value specified at mount time is
2367 * greater than the blocks per group use the super block value.
2368 * If the super block value is greater than blocks per group return 0.
2369 * Allocator needs it be less than blocks per group.
2370 *
2371 */
2372static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2373{
2374	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2375	unsigned long stripe_width =
2376			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2377	int ret;
2378
2379	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2380		ret = sbi->s_stripe;
2381	else if (stripe_width <= sbi->s_blocks_per_group)
2382		ret = stripe_width;
2383	else if (stride <= sbi->s_blocks_per_group)
2384		ret = stride;
2385	else
2386		ret = 0;
2387
2388	/*
2389	 * If the stripe width is 1, this makes no sense and
2390	 * we set it to 0 to turn off stripe handling code.
2391	 */
2392	if (ret <= 1)
2393		ret = 0;
2394
2395	return ret;
2396}
2397
2398/* sysfs supprt */
2399
2400struct ext4_attr {
2401	struct attribute attr;
2402	ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2403	ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2404			 const char *, size_t);
2405	int offset;
2406};
2407
2408static int parse_strtoul(const char *buf,
2409		unsigned long max, unsigned long *value)
2410{
2411	char *endp;
2412
2413	*value = simple_strtoul(skip_spaces(buf), &endp, 0);
2414	endp = skip_spaces(endp);
2415	if (*endp || *value > max)
2416		return -EINVAL;
2417
2418	return 0;
2419}
2420
2421static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2422					      struct ext4_sb_info *sbi,
2423					      char *buf)
2424{
2425	return snprintf(buf, PAGE_SIZE, "%llu\n",
2426		(s64) EXT4_C2B(sbi,
2427			percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2428}
2429
2430static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2431					 struct ext4_sb_info *sbi, char *buf)
2432{
2433	struct super_block *sb = sbi->s_buddy_cache->i_sb;
2434
2435	if (!sb->s_bdev->bd_part)
2436		return snprintf(buf, PAGE_SIZE, "0\n");
2437	return snprintf(buf, PAGE_SIZE, "%lu\n",
2438			(part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2439			 sbi->s_sectors_written_start) >> 1);
2440}
2441
2442static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2443					  struct ext4_sb_info *sbi, char *buf)
2444{
2445	struct super_block *sb = sbi->s_buddy_cache->i_sb;
2446
2447	if (!sb->s_bdev->bd_part)
2448		return snprintf(buf, PAGE_SIZE, "0\n");
2449	return snprintf(buf, PAGE_SIZE, "%llu\n",
2450			(unsigned long long)(sbi->s_kbytes_written +
2451			((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2452			  EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2453}
2454
2455static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2456					  struct ext4_sb_info *sbi,
2457					  const char *buf, size_t count)
2458{
2459	unsigned long t;
2460
2461	if (parse_strtoul(buf, 0x40000000, &t))
2462		return -EINVAL;
2463
2464	if (t && !is_power_of_2(t))
2465		return -EINVAL;
2466
2467	sbi->s_inode_readahead_blks = t;
2468	return count;
2469}
2470
2471static ssize_t sbi_ui_show(struct ext4_attr *a,
2472			   struct ext4_sb_info *sbi, char *buf)
2473{
2474	unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2475
2476	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2477}
2478
2479static ssize_t sbi_ui_store(struct ext4_attr *a,
2480			    struct ext4_sb_info *sbi,
2481			    const char *buf, size_t count)
2482{
2483	unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2484	unsigned long t;
2485
2486	if (parse_strtoul(buf, 0xffffffff, &t))
2487		return -EINVAL;
2488	*ui = t;
2489	return count;
2490}
2491
2492static ssize_t trigger_test_error(struct ext4_attr *a,
2493				  struct ext4_sb_info *sbi,
2494				  const char *buf, size_t count)
2495{
2496	int len = count;
2497
2498	if (!capable(CAP_SYS_ADMIN))
2499		return -EPERM;
2500
2501	if (len && buf[len-1] == '\n')
2502		len--;
2503
2504	if (len)
2505		ext4_error(sbi->s_sb, "%.*s", len, buf);
2506	return count;
2507}
2508
2509#define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2510static struct ext4_attr ext4_attr_##_name = {			\
2511	.attr = {.name = __stringify(_name), .mode = _mode },	\
2512	.show	= _show,					\
2513	.store	= _store,					\
2514	.offset = offsetof(struct ext4_sb_info, _elname),	\
2515}
2516#define EXT4_ATTR(name, mode, show, store) \
2517static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2518
2519#define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2520#define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2521#define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2522#define EXT4_RW_ATTR_SBI_UI(name, elname)	\
2523	EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2524#define ATTR_LIST(name) &ext4_attr_##name.attr
2525
2526EXT4_RO_ATTR(delayed_allocation_blocks);
2527EXT4_RO_ATTR(session_write_kbytes);
2528EXT4_RO_ATTR(lifetime_write_kbytes);
2529EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2530		 inode_readahead_blks_store, s_inode_readahead_blks);
2531EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2532EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2533EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2534EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2535EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2536EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2537EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2538EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2539EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2540
2541static struct attribute *ext4_attrs[] = {
2542	ATTR_LIST(delayed_allocation_blocks),
2543	ATTR_LIST(session_write_kbytes),
2544	ATTR_LIST(lifetime_write_kbytes),
2545	ATTR_LIST(inode_readahead_blks),
2546	ATTR_LIST(inode_goal),
2547	ATTR_LIST(mb_stats),
2548	ATTR_LIST(mb_max_to_scan),
2549	ATTR_LIST(mb_min_to_scan),
2550	ATTR_LIST(mb_order2_req),
2551	ATTR_LIST(mb_stream_req),
2552	ATTR_LIST(mb_group_prealloc),
2553	ATTR_LIST(max_writeback_mb_bump),
2554	ATTR_LIST(trigger_fs_error),
2555	NULL,
2556};
2557
2558/* Features this copy of ext4 supports */
2559EXT4_INFO_ATTR(lazy_itable_init);
2560EXT4_INFO_ATTR(batched_discard);
2561
2562static struct attribute *ext4_feat_attrs[] = {
2563	ATTR_LIST(lazy_itable_init),
2564	ATTR_LIST(batched_discard),
2565	NULL,
2566};
2567
2568static ssize_t ext4_attr_show(struct kobject *kobj,
2569			      struct attribute *attr, char *buf)
2570{
2571	struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2572						s_kobj);
2573	struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2574
2575	return a->show ? a->show(a, sbi, buf) : 0;
2576}
2577
2578static ssize_t ext4_attr_store(struct kobject *kobj,
2579			       struct attribute *attr,
2580			       const char *buf, size_t len)
2581{
2582	struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2583						s_kobj);
2584	struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2585
2586	return a->store ? a->store(a, sbi, buf, len) : 0;
2587}
2588
2589static void ext4_sb_release(struct kobject *kobj)
2590{
2591	struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2592						s_kobj);
2593	complete(&sbi->s_kobj_unregister);
2594}
2595
2596static const struct sysfs_ops ext4_attr_ops = {
2597	.show	= ext4_attr_show,
2598	.store	= ext4_attr_store,
2599};
2600
2601static struct kobj_type ext4_ktype = {
2602	.default_attrs	= ext4_attrs,
2603	.sysfs_ops	= &ext4_attr_ops,
2604	.release	= ext4_sb_release,
2605};
2606
2607static void ext4_feat_release(struct kobject *kobj)
2608{
2609	complete(&ext4_feat->f_kobj_unregister);
2610}
2611
2612static struct kobj_type ext4_feat_ktype = {
2613	.default_attrs	= ext4_feat_attrs,
2614	.sysfs_ops	= &ext4_attr_ops,
2615	.release	= ext4_feat_release,
2616};
2617
2618/*
2619 * Check whether this filesystem can be mounted based on
2620 * the features present and the RDONLY/RDWR mount requested.
2621 * Returns 1 if this filesystem can be mounted as requested,
2622 * 0 if it cannot be.
2623 */
2624static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2625{
2626	if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2627		ext4_msg(sb, KERN_ERR,
2628			"Couldn't mount because of "
2629			"unsupported optional features (%x)",
2630			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2631			~EXT4_FEATURE_INCOMPAT_SUPP));
2632		return 0;
2633	}
2634
 
 
 
 
 
 
 
2635	if (readonly)
2636		return 1;
2637
 
 
 
 
 
 
2638	/* Check that feature set is OK for a read-write mount */
2639	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2640		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2641			 "unsupported optional features (%x)",
2642			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2643				~EXT4_FEATURE_RO_COMPAT_SUPP));
2644		return 0;
2645	}
2646	/*
2647	 * Large file size enabled file system can only be mounted
2648	 * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2649	 */
2650	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2651		if (sizeof(blkcnt_t) < sizeof(u64)) {
2652			ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2653				 "cannot be mounted RDWR without "
2654				 "CONFIG_LBDAF");
2655			return 0;
2656		}
2657	}
2658	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2659	    !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2660		ext4_msg(sb, KERN_ERR,
2661			 "Can't support bigalloc feature without "
2662			 "extents feature\n");
2663		return 0;
2664	}
 
 
 
 
 
 
 
 
 
2665	return 1;
2666}
2667
2668/*
2669 * This function is called once a day if we have errors logged
2670 * on the file system
2671 */
2672static void print_daily_error_info(unsigned long arg)
2673{
2674	struct super_block *sb = (struct super_block *) arg;
2675	struct ext4_sb_info *sbi;
2676	struct ext4_super_block *es;
2677
2678	sbi = EXT4_SB(sb);
2679	es = sbi->s_es;
2680
2681	if (es->s_error_count)
2682		ext4_msg(sb, KERN_NOTICE, "error count: %u",
 
2683			 le32_to_cpu(es->s_error_count));
2684	if (es->s_first_error_time) {
2685		printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2686		       sb->s_id, le32_to_cpu(es->s_first_error_time),
 
2687		       (int) sizeof(es->s_first_error_func),
2688		       es->s_first_error_func,
2689		       le32_to_cpu(es->s_first_error_line));
2690		if (es->s_first_error_ino)
2691			printk(": inode %u",
2692			       le32_to_cpu(es->s_first_error_ino));
2693		if (es->s_first_error_block)
2694			printk(": block %llu", (unsigned long long)
2695			       le64_to_cpu(es->s_first_error_block));
2696		printk("\n");
2697	}
2698	if (es->s_last_error_time) {
2699		printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2700		       sb->s_id, le32_to_cpu(es->s_last_error_time),
 
2701		       (int) sizeof(es->s_last_error_func),
2702		       es->s_last_error_func,
2703		       le32_to_cpu(es->s_last_error_line));
2704		if (es->s_last_error_ino)
2705			printk(": inode %u",
2706			       le32_to_cpu(es->s_last_error_ino));
2707		if (es->s_last_error_block)
2708			printk(": block %llu", (unsigned long long)
2709			       le64_to_cpu(es->s_last_error_block));
2710		printk("\n");
2711	}
2712	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2713}
2714
2715/* Find next suitable group and run ext4_init_inode_table */
2716static int ext4_run_li_request(struct ext4_li_request *elr)
2717{
2718	struct ext4_group_desc *gdp = NULL;
2719	ext4_group_t group, ngroups;
2720	struct super_block *sb;
2721	unsigned long timeout = 0;
 
2722	int ret = 0;
 
 
2723
2724	sb = elr->lr_super;
2725	ngroups = EXT4_SB(sb)->s_groups_count;
 
 
 
 
 
 
 
 
 
 
 
 
 
2726
2727	for (group = elr->lr_next_group; group < ngroups; group++) {
2728		gdp = ext4_get_group_desc(sb, group, NULL);
2729		if (!gdp) {
2730			ret = 1;
2731			break;
2732		}
2733
2734		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2735			break;
2736	}
2737
2738	if (group == ngroups)
2739		ret = 1;
2740
2741	if (!ret) {
2742		timeout = jiffies;
2743		ret = ext4_init_inode_table(sb, group,
2744					    elr->lr_timeout ? 0 : 1);
 
2745		if (elr->lr_timeout == 0) {
2746			timeout = (jiffies - timeout) *
2747				  elr->lr_sbi->s_li_wait_mult;
2748			elr->lr_timeout = timeout;
2749		}
2750		elr->lr_next_sched = jiffies + elr->lr_timeout;
2751		elr->lr_next_group = group + 1;
2752	}
2753
2754	return ret;
2755}
2756
2757/*
2758 * Remove lr_request from the list_request and free the
2759 * request structure. Should be called with li_list_mtx held
2760 */
2761static void ext4_remove_li_request(struct ext4_li_request *elr)
2762{
2763	struct ext4_sb_info *sbi;
2764
2765	if (!elr)
2766		return;
2767
2768	sbi = elr->lr_sbi;
2769
2770	list_del(&elr->lr_request);
2771	sbi->s_li_request = NULL;
2772	kfree(elr);
2773}
2774
2775static void ext4_unregister_li_request(struct super_block *sb)
2776{
2777	mutex_lock(&ext4_li_mtx);
2778	if (!ext4_li_info) {
2779		mutex_unlock(&ext4_li_mtx);
2780		return;
2781	}
2782
2783	mutex_lock(&ext4_li_info->li_list_mtx);
2784	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2785	mutex_unlock(&ext4_li_info->li_list_mtx);
2786	mutex_unlock(&ext4_li_mtx);
2787}
2788
2789static struct task_struct *ext4_lazyinit_task;
2790
2791/*
2792 * This is the function where ext4lazyinit thread lives. It walks
2793 * through the request list searching for next scheduled filesystem.
2794 * When such a fs is found, run the lazy initialization request
2795 * (ext4_rn_li_request) and keep track of the time spend in this
2796 * function. Based on that time we compute next schedule time of
2797 * the request. When walking through the list is complete, compute
2798 * next waking time and put itself into sleep.
2799 */
2800static int ext4_lazyinit_thread(void *arg)
2801{
2802	struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2803	struct list_head *pos, *n;
2804	struct ext4_li_request *elr;
2805	unsigned long next_wakeup, cur;
2806
2807	BUG_ON(NULL == eli);
 
2808
2809cont_thread:
2810	while (true) {
2811		next_wakeup = MAX_JIFFY_OFFSET;
2812
 
2813		mutex_lock(&eli->li_list_mtx);
2814		if (list_empty(&eli->li_request_list)) {
2815			mutex_unlock(&eli->li_list_mtx);
2816			goto exit_thread;
2817		}
2818
2819		list_for_each_safe(pos, n, &eli->li_request_list) {
 
 
2820			elr = list_entry(pos, struct ext4_li_request,
2821					 lr_request);
2822
2823			if (time_after_eq(jiffies, elr->lr_next_sched)) {
2824				if (ext4_run_li_request(elr) != 0) {
2825					/* error, remove the lazy_init job */
2826					ext4_remove_li_request(elr);
2827					continue;
2828				}
 
2829			}
2830
2831			if (time_before(elr->lr_next_sched, next_wakeup))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2832				next_wakeup = elr->lr_next_sched;
 
 
2833		}
2834		mutex_unlock(&eli->li_list_mtx);
2835
2836		try_to_freeze();
2837
2838		cur = jiffies;
2839		if ((time_after_eq(cur, next_wakeup)) ||
2840		    (MAX_JIFFY_OFFSET == next_wakeup)) {
2841			cond_resched();
2842			continue;
2843		}
2844
2845		schedule_timeout_interruptible(next_wakeup - cur);
2846
2847		if (kthread_should_stop()) {
2848			ext4_clear_request_list();
2849			goto exit_thread;
2850		}
2851	}
2852
2853exit_thread:
2854	/*
2855	 * It looks like the request list is empty, but we need
2856	 * to check it under the li_list_mtx lock, to prevent any
2857	 * additions into it, and of course we should lock ext4_li_mtx
2858	 * to atomically free the list and ext4_li_info, because at
2859	 * this point another ext4 filesystem could be registering
2860	 * new one.
2861	 */
2862	mutex_lock(&ext4_li_mtx);
2863	mutex_lock(&eli->li_list_mtx);
2864	if (!list_empty(&eli->li_request_list)) {
2865		mutex_unlock(&eli->li_list_mtx);
2866		mutex_unlock(&ext4_li_mtx);
2867		goto cont_thread;
2868	}
2869	mutex_unlock(&eli->li_list_mtx);
2870	kfree(ext4_li_info);
2871	ext4_li_info = NULL;
2872	mutex_unlock(&ext4_li_mtx);
2873
2874	return 0;
2875}
2876
2877static void ext4_clear_request_list(void)
2878{
2879	struct list_head *pos, *n;
2880	struct ext4_li_request *elr;
2881
2882	mutex_lock(&ext4_li_info->li_list_mtx);
2883	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2884		elr = list_entry(pos, struct ext4_li_request,
2885				 lr_request);
2886		ext4_remove_li_request(elr);
2887	}
2888	mutex_unlock(&ext4_li_info->li_list_mtx);
2889}
2890
2891static int ext4_run_lazyinit_thread(void)
2892{
2893	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2894					 ext4_li_info, "ext4lazyinit");
2895	if (IS_ERR(ext4_lazyinit_task)) {
2896		int err = PTR_ERR(ext4_lazyinit_task);
2897		ext4_clear_request_list();
2898		kfree(ext4_li_info);
2899		ext4_li_info = NULL;
2900		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2901				 "initialization thread\n",
2902				 err);
2903		return err;
2904	}
2905	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2906	return 0;
2907}
2908
2909/*
2910 * Check whether it make sense to run itable init. thread or not.
2911 * If there is at least one uninitialized inode table, return
2912 * corresponding group number, else the loop goes through all
2913 * groups and return total number of groups.
2914 */
2915static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2916{
2917	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2918	struct ext4_group_desc *gdp = NULL;
2919
 
 
 
2920	for (group = 0; group < ngroups; group++) {
2921		gdp = ext4_get_group_desc(sb, group, NULL);
2922		if (!gdp)
2923			continue;
2924
2925		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2926			break;
2927	}
2928
2929	return group;
2930}
2931
2932static int ext4_li_info_new(void)
2933{
2934	struct ext4_lazy_init *eli = NULL;
2935
2936	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2937	if (!eli)
2938		return -ENOMEM;
2939
2940	INIT_LIST_HEAD(&eli->li_request_list);
2941	mutex_init(&eli->li_list_mtx);
2942
2943	eli->li_state |= EXT4_LAZYINIT_QUIT;
2944
2945	ext4_li_info = eli;
2946
2947	return 0;
2948}
2949
2950static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2951					    ext4_group_t start)
2952{
2953	struct ext4_sb_info *sbi = EXT4_SB(sb);
2954	struct ext4_li_request *elr;
2955	unsigned long rnd;
2956
2957	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2958	if (!elr)
2959		return NULL;
2960
2961	elr->lr_super = sb;
2962	elr->lr_sbi = sbi;
2963	elr->lr_next_group = start;
 
 
 
 
 
2964
2965	/*
2966	 * Randomize first schedule time of the request to
2967	 * spread the inode table initialization requests
2968	 * better.
2969	 */
2970	get_random_bytes(&rnd, sizeof(rnd));
2971	elr->lr_next_sched = jiffies + (unsigned long)rnd %
2972			     (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2973
2974	return elr;
2975}
2976
2977static int ext4_register_li_request(struct super_block *sb,
2978				    ext4_group_t first_not_zeroed)
2979{
2980	struct ext4_sb_info *sbi = EXT4_SB(sb);
2981	struct ext4_li_request *elr;
2982	ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2983	int ret = 0;
2984
 
2985	if (sbi->s_li_request != NULL) {
2986		/*
2987		 * Reset timeout so it can be computed again, because
2988		 * s_li_wait_mult might have changed.
2989		 */
2990		sbi->s_li_request->lr_timeout = 0;
2991		return 0;
2992	}
2993
2994	if (first_not_zeroed == ngroups ||
2995	    (sb->s_flags & MS_RDONLY) ||
2996	    !test_opt(sb, INIT_INODE_TABLE))
2997		return 0;
2998
2999	elr = ext4_li_request_new(sb, first_not_zeroed);
3000	if (!elr)
3001		return -ENOMEM;
3002
3003	mutex_lock(&ext4_li_mtx);
3004
3005	if (NULL == ext4_li_info) {
3006		ret = ext4_li_info_new();
3007		if (ret)
3008			goto out;
3009	}
3010
3011	mutex_lock(&ext4_li_info->li_list_mtx);
3012	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3013	mutex_unlock(&ext4_li_info->li_list_mtx);
3014
3015	sbi->s_li_request = elr;
3016	/*
3017	 * set elr to NULL here since it has been inserted to
3018	 * the request_list and the removal and free of it is
3019	 * handled by ext4_clear_request_list from now on.
3020	 */
3021	elr = NULL;
3022
3023	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3024		ret = ext4_run_lazyinit_thread();
3025		if (ret)
3026			goto out;
3027	}
3028out:
3029	mutex_unlock(&ext4_li_mtx);
3030	if (ret)
3031		kfree(elr);
3032	return ret;
3033}
3034
3035/*
3036 * We do not need to lock anything since this is called on
3037 * module unload.
3038 */
3039static void ext4_destroy_lazyinit_thread(void)
3040{
3041	/*
3042	 * If thread exited earlier
3043	 * there's nothing to be done.
3044	 */
3045	if (!ext4_li_info || !ext4_lazyinit_task)
3046		return;
3047
3048	kthread_stop(ext4_lazyinit_task);
3049}
3050
3051static int set_journal_csum_feature_set(struct super_block *sb)
3052{
3053	int ret = 1;
3054	int compat, incompat;
3055	struct ext4_sb_info *sbi = EXT4_SB(sb);
3056
3057	if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3058				       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3059		/* journal checksum v2 */
3060		compat = 0;
3061		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3062	} else {
3063		/* journal checksum v1 */
3064		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3065		incompat = 0;
3066	}
3067
 
 
 
 
3068	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3069		ret = jbd2_journal_set_features(sbi->s_journal,
3070				compat, 0,
3071				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3072				incompat);
3073	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3074		ret = jbd2_journal_set_features(sbi->s_journal,
3075				compat, 0,
3076				incompat);
3077		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3078				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3079	} else {
3080		jbd2_journal_clear_features(sbi->s_journal,
3081				JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3082				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3083				JBD2_FEATURE_INCOMPAT_CSUM_V2);
3084	}
3085
3086	return ret;
3087}
3088
3089/*
3090 * Note: calculating the overhead so we can be compatible with
3091 * historical BSD practice is quite difficult in the face of
3092 * clusters/bigalloc.  This is because multiple metadata blocks from
3093 * different block group can end up in the same allocation cluster.
3094 * Calculating the exact overhead in the face of clustered allocation
3095 * requires either O(all block bitmaps) in memory or O(number of block
3096 * groups**2) in time.  We will still calculate the superblock for
3097 * older file systems --- and if we come across with a bigalloc file
3098 * system with zero in s_overhead_clusters the estimate will be close to
3099 * correct especially for very large cluster sizes --- but for newer
3100 * file systems, it's better to calculate this figure once at mkfs
3101 * time, and store it in the superblock.  If the superblock value is
3102 * present (even for non-bigalloc file systems), we will use it.
3103 */
3104static int count_overhead(struct super_block *sb, ext4_group_t grp,
3105			  char *buf)
3106{
3107	struct ext4_sb_info	*sbi = EXT4_SB(sb);
3108	struct ext4_group_desc	*gdp;
3109	ext4_fsblk_t		first_block, last_block, b;
3110	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
3111	int			s, j, count = 0;
 
3112
3113	if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3114		return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
 
3115			sbi->s_itb_per_group + 2);
3116
3117	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3118		(grp * EXT4_BLOCKS_PER_GROUP(sb));
3119	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3120	for (i = 0; i < ngroups; i++) {
3121		gdp = ext4_get_group_desc(sb, i, NULL);
3122		b = ext4_block_bitmap(sb, gdp);
3123		if (b >= first_block && b <= last_block) {
3124			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3125			count++;
3126		}
3127		b = ext4_inode_bitmap(sb, gdp);
3128		if (b >= first_block && b <= last_block) {
3129			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3130			count++;
3131		}
3132		b = ext4_inode_table(sb, gdp);
3133		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3134			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3135				int c = EXT4_B2C(sbi, b - first_block);
3136				ext4_set_bit(c, buf);
3137				count++;
3138			}
3139		if (i != grp)
3140			continue;
3141		s = 0;
3142		if (ext4_bg_has_super(sb, grp)) {
3143			ext4_set_bit(s++, buf);
3144			count++;
3145		}
3146		for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3147			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3148			count++;
 
 
3149		}
 
 
 
3150	}
3151	if (!count)
3152		return 0;
3153	return EXT4_CLUSTERS_PER_GROUP(sb) -
3154		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3155}
3156
3157/*
3158 * Compute the overhead and stash it in sbi->s_overhead
3159 */
3160int ext4_calculate_overhead(struct super_block *sb)
3161{
3162	struct ext4_sb_info *sbi = EXT4_SB(sb);
3163	struct ext4_super_block *es = sbi->s_es;
 
 
3164	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3165	ext4_fsblk_t overhead = 0;
3166	char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3167
3168	memset(buf, 0, PAGE_SIZE);
3169	if (!buf)
3170		return -ENOMEM;
3171
3172	/*
3173	 * Compute the overhead (FS structures).  This is constant
3174	 * for a given filesystem unless the number of block groups
3175	 * changes so we cache the previous value until it does.
3176	 */
3177
3178	/*
3179	 * All of the blocks before first_data_block are overhead
3180	 */
3181	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3182
3183	/*
3184	 * Add the overhead found in each block group
3185	 */
3186	for (i = 0; i < ngroups; i++) {
3187		int blks;
3188
3189		blks = count_overhead(sb, i, buf);
3190		overhead += blks;
3191		if (blks)
3192			memset(buf, 0, PAGE_SIZE);
3193		cond_resched();
3194	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3195	sbi->s_overhead = overhead;
3196	smp_wmb();
3197	free_page((unsigned long) buf);
3198	return 0;
3199}
3200
3201static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3202{
3203	char *orig_data = kstrdup(data, GFP_KERNEL);
3204	struct buffer_head *bh;
3205	struct ext4_super_block *es = NULL;
3206	struct ext4_sb_info *sbi;
3207	ext4_fsblk_t block;
3208	ext4_fsblk_t sb_block = get_sb_block(&data);
3209	ext4_fsblk_t logical_sb_block;
3210	unsigned long offset = 0;
3211	unsigned long journal_devnum = 0;
3212	unsigned long def_mount_opts;
3213	struct inode *root;
3214	char *cp;
3215	const char *descr;
3216	int ret = -ENOMEM;
3217	int blocksize, clustersize;
3218	unsigned int db_count;
3219	unsigned int i;
3220	int needs_recovery, has_huge_files, has_bigalloc;
3221	__u64 blocks_count;
3222	int err;
3223	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3224	ext4_group_t first_not_zeroed;
3225
3226	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3227	if (!sbi)
3228		goto out_free_orig;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3229
3230	sbi->s_blockgroup_lock =
3231		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3232	if (!sbi->s_blockgroup_lock) {
3233		kfree(sbi);
3234		goto out_free_orig;
3235	}
3236	sb->s_fs_info = sbi;
3237	sbi->s_sb = sb;
3238	sbi->s_mount_opt = 0;
3239	sbi->s_resuid = make_kuid(&init_user_ns, EXT4_DEF_RESUID);
3240	sbi->s_resgid = make_kgid(&init_user_ns, EXT4_DEF_RESGID);
3241	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3242	sbi->s_sb_block = sb_block;
3243	if (sb->s_bdev->bd_part)
3244		sbi->s_sectors_written_start =
3245			part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3246
3247	/* Cleanup superblock name */
3248	for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3249		*cp = '!';
3250
3251	ret = -EINVAL;
3252	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3253	if (!blocksize) {
3254		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3255		goto out_fail;
3256	}
3257
3258	/*
3259	 * The ext4 superblock will not be buffer aligned for other than 1kB
3260	 * block sizes.  We need to calculate the offset from buffer start.
3261	 */
3262	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3263		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3264		offset = do_div(logical_sb_block, blocksize);
3265	} else {
3266		logical_sb_block = sb_block;
3267	}
3268
3269	if (!(bh = sb_bread(sb, logical_sb_block))) {
3270		ext4_msg(sb, KERN_ERR, "unable to read superblock");
3271		goto out_fail;
3272	}
3273	/*
3274	 * Note: s_es must be initialized as soon as possible because
3275	 *       some ext4 macro-instructions depend on its value
3276	 */
3277	es = (struct ext4_super_block *) (bh->b_data + offset);
3278	sbi->s_es = es;
3279	sb->s_magic = le16_to_cpu(es->s_magic);
3280	if (sb->s_magic != EXT4_SUPER_MAGIC)
3281		goto cantfind_ext4;
3282	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3283
3284	/* Warn if metadata_csum and gdt_csum are both set. */
3285	if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3286				       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3287	    EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3288		ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3289			     "redundant flags; please run fsck.");
3290
3291	/* Check for a known checksum algorithm */
3292	if (!ext4_verify_csum_type(sb, es)) {
3293		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3294			 "unknown checksum algorithm.");
3295		silent = 1;
3296		goto cantfind_ext4;
3297	}
3298
3299	/* Load the checksum driver */
3300	if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3301				       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3302		sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3303		if (IS_ERR(sbi->s_chksum_driver)) {
3304			ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3305			ret = PTR_ERR(sbi->s_chksum_driver);
3306			sbi->s_chksum_driver = NULL;
3307			goto failed_mount;
3308		}
3309	}
3310
3311	/* Check superblock checksum */
3312	if (!ext4_superblock_csum_verify(sb, es)) {
3313		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3314			 "invalid superblock checksum.  Run e2fsck?");
3315		silent = 1;
3316		goto cantfind_ext4;
3317	}
3318
3319	/* Precompute checksum seed for all metadata */
3320	if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3321			EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3322		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3323					       sizeof(es->s_uuid));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3324
3325	/* Set defaults before we parse the mount options */
3326	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3327	set_opt(sb, INIT_INODE_TABLE);
3328	if (def_mount_opts & EXT4_DEFM_DEBUG)
3329		set_opt(sb, DEBUG);
3330	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3331		set_opt(sb, GRPID);
3332	if (def_mount_opts & EXT4_DEFM_UID16)
3333		set_opt(sb, NO_UID32);
3334	/* xattr user namespace & acls are now defaulted on */
3335#ifdef CONFIG_EXT4_FS_XATTR
3336	set_opt(sb, XATTR_USER);
3337#endif
3338#ifdef CONFIG_EXT4_FS_POSIX_ACL
3339	set_opt(sb, POSIX_ACL);
3340#endif
3341	set_opt(sb, MBLK_IO_SUBMIT);
 
 
 
 
 
3342	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3343		set_opt(sb, JOURNAL_DATA);
3344	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3345		set_opt(sb, ORDERED_DATA);
3346	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3347		set_opt(sb, WRITEBACK_DATA);
3348
3349	if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3350		set_opt(sb, ERRORS_PANIC);
3351	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3352		set_opt(sb, ERRORS_CONT);
3353	else
3354		set_opt(sb, ERRORS_RO);
3355	if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3356		set_opt(sb, BLOCK_VALIDITY);
3357	if (def_mount_opts & EXT4_DEFM_DISCARD)
3358		set_opt(sb, DISCARD);
3359
3360	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3361	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3362	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3363	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3364	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3365
3366	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3367		set_opt(sb, BARRIER);
3368
3369	/*
3370	 * enable delayed allocation by default
3371	 * Use -o nodelalloc to turn it off
3372	 */
3373	if (!IS_EXT3_SB(sb) &&
3374	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3375		set_opt(sb, DELALLOC);
3376
3377	/*
3378	 * set default s_li_wait_mult for lazyinit, for the case there is
3379	 * no mount option specified.
3380	 */
3381	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3382
3383	if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3384			   &journal_devnum, &journal_ioprio, 0)) {
3385		ext4_msg(sb, KERN_WARNING,
3386			 "failed to parse options in superblock: %s",
3387			 sbi->s_es->s_mount_opts);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3388	}
3389	sbi->s_def_mount_opt = sbi->s_mount_opt;
3390	if (!parse_options((char *) data, sb, &journal_devnum,
3391			   &journal_ioprio, 0))
3392		goto failed_mount;
 
 
 
 
 
 
 
 
 
 
3393
3394	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3395		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3396			    "with data=journal disables delayed "
3397			    "allocation and O_DIRECT support!\n");
3398		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3399			ext4_msg(sb, KERN_ERR, "can't mount with "
3400				 "both data=journal and delalloc");
3401			goto failed_mount;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3402		}
3403		if (test_opt(sb, DIOREAD_NOLOCK)) {
3404			ext4_msg(sb, KERN_ERR, "can't mount with "
3405				 "both data=journal and delalloc");
3406			goto failed_mount;
 
 
 
 
3407		}
3408		if (test_opt(sb, DELALLOC))
3409			clear_opt(sb, DELALLOC);
 
 
 
 
 
 
 
 
 
 
 
 
 
3410	}
3411
3412	blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3413	if (test_opt(sb, DIOREAD_NOLOCK)) {
3414		if (blocksize < PAGE_SIZE) {
3415			ext4_msg(sb, KERN_ERR, "can't mount with "
3416				 "dioread_nolock if block size != PAGE_SIZE");
3417			goto failed_mount;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3418		}
3419	}
3420
3421	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3422		(test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3423
3424	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3425	    (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3426	     EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3427	     EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3428		ext4_msg(sb, KERN_WARNING,
3429		       "feature flags set on rev 0 fs, "
3430		       "running e2fsck is recommended");
3431
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3432	if (IS_EXT2_SB(sb)) {
3433		if (ext2_feature_set_ok(sb))
3434			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3435				 "using the ext4 subsystem");
3436		else {
 
 
 
 
 
 
3437			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3438				 "to feature incompatibilities");
3439			goto failed_mount;
3440		}
3441	}
3442
3443	if (IS_EXT3_SB(sb)) {
3444		if (ext3_feature_set_ok(sb))
3445			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3446				 "using the ext4 subsystem");
3447		else {
 
 
 
 
 
 
3448			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3449				 "to feature incompatibilities");
3450			goto failed_mount;
3451		}
3452	}
3453
3454	/*
3455	 * Check feature flags regardless of the revision level, since we
3456	 * previously didn't change the revision level when setting the flags,
3457	 * so there is a chance incompat flags are set on a rev 0 filesystem.
3458	 */
3459	if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3460		goto failed_mount;
3461
3462	if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3463	    blocksize > EXT4_MAX_BLOCK_SIZE) {
3464		ext4_msg(sb, KERN_ERR,
3465		       "Unsupported filesystem blocksize %d", blocksize);
3466		goto failed_mount;
3467	}
3468
3469	if (sb->s_blocksize != blocksize) {
3470		/* Validate the filesystem blocksize */
3471		if (!sb_set_blocksize(sb, blocksize)) {
3472			ext4_msg(sb, KERN_ERR, "bad block size %d",
3473					blocksize);
3474			goto failed_mount;
3475		}
3476
3477		brelse(bh);
3478		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3479		offset = do_div(logical_sb_block, blocksize);
3480		bh = sb_bread(sb, logical_sb_block);
3481		if (!bh) {
3482			ext4_msg(sb, KERN_ERR,
3483			       "Can't read superblock on 2nd try");
3484			goto failed_mount;
3485		}
3486		es = (struct ext4_super_block *)(bh->b_data + offset);
3487		sbi->s_es = es;
3488		if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3489			ext4_msg(sb, KERN_ERR,
3490			       "Magic mismatch, very weird!");
3491			goto failed_mount;
3492		}
3493	}
3494
3495	has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3496				EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3497	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3498						      has_huge_files);
3499	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3500
3501	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3502		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3503		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3504	} else {
3505		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3506		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3507		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3508		    (!is_power_of_2(sbi->s_inode_size)) ||
3509		    (sbi->s_inode_size > blocksize)) {
3510			ext4_msg(sb, KERN_ERR,
3511			       "unsupported inode size: %d",
3512			       sbi->s_inode_size);
3513			goto failed_mount;
3514		}
3515		if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3516			sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3517	}
3518
3519	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3520	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3521		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3522		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3523		    !is_power_of_2(sbi->s_desc_size)) {
3524			ext4_msg(sb, KERN_ERR,
3525			       "unsupported descriptor size %lu",
3526			       sbi->s_desc_size);
3527			goto failed_mount;
3528		}
3529	} else
3530		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3531
3532	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3533	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3534	if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3535		goto cantfind_ext4;
3536
3537	sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3538	if (sbi->s_inodes_per_block == 0)
3539		goto cantfind_ext4;
3540	sbi->s_itb_per_group = sbi->s_inodes_per_group /
3541					sbi->s_inodes_per_block;
3542	sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3543	sbi->s_sbh = bh;
3544	sbi->s_mount_state = le16_to_cpu(es->s_state);
3545	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3546	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3547
3548	for (i = 0; i < 4; i++)
3549		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3550	sbi->s_def_hash_version = es->s_def_hash_version;
3551	i = le32_to_cpu(es->s_flags);
3552	if (i & EXT2_FLAGS_UNSIGNED_HASH)
3553		sbi->s_hash_unsigned = 3;
3554	else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3555#ifdef __CHAR_UNSIGNED__
3556		es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3557		sbi->s_hash_unsigned = 3;
3558#else
3559		es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3560#endif
3561	}
3562
3563	/* Handle clustersize */
3564	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3565	has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3566				EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3567	if (has_bigalloc) {
3568		if (clustersize < blocksize) {
3569			ext4_msg(sb, KERN_ERR,
3570				 "cluster size (%d) smaller than "
3571				 "block size (%d)", clustersize, blocksize);
3572			goto failed_mount;
3573		}
3574		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3575			le32_to_cpu(es->s_log_block_size);
3576		sbi->s_clusters_per_group =
3577			le32_to_cpu(es->s_clusters_per_group);
3578		if (sbi->s_clusters_per_group > blocksize * 8) {
3579			ext4_msg(sb, KERN_ERR,
3580				 "#clusters per group too big: %lu",
3581				 sbi->s_clusters_per_group);
3582			goto failed_mount;
3583		}
3584		if (sbi->s_blocks_per_group !=
3585		    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3586			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3587				 "clusters per group (%lu) inconsistent",
3588				 sbi->s_blocks_per_group,
3589				 sbi->s_clusters_per_group);
3590			goto failed_mount;
3591		}
3592	} else {
3593		if (clustersize != blocksize) {
3594			ext4_warning(sb, "fragment/cluster size (%d) != "
3595				     "block size (%d)", clustersize,
3596				     blocksize);
3597			clustersize = blocksize;
3598		}
3599		if (sbi->s_blocks_per_group > blocksize * 8) {
3600			ext4_msg(sb, KERN_ERR,
3601				 "#blocks per group too big: %lu",
3602				 sbi->s_blocks_per_group);
3603			goto failed_mount;
3604		}
3605		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3606		sbi->s_cluster_bits = 0;
3607	}
3608	sbi->s_cluster_ratio = clustersize / blocksize;
3609
3610	if (sbi->s_inodes_per_group > blocksize * 8) {
3611		ext4_msg(sb, KERN_ERR,
3612		       "#inodes per group too big: %lu",
3613		       sbi->s_inodes_per_group);
3614		goto failed_mount;
3615	}
3616
3617	/*
3618	 * Test whether we have more sectors than will fit in sector_t,
3619	 * and whether the max offset is addressable by the page cache.
3620	 */
3621	err = generic_check_addressable(sb->s_blocksize_bits,
3622					ext4_blocks_count(es));
3623	if (err) {
3624		ext4_msg(sb, KERN_ERR, "filesystem"
3625			 " too large to mount safely on this system");
3626		if (sizeof(sector_t) < 8)
3627			ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3628		ret = err;
3629		goto failed_mount;
3630	}
3631
3632	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3633		goto cantfind_ext4;
3634
3635	/* check blocks count against device size */
3636	blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3637	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3638		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3639		       "exceeds size of device (%llu blocks)",
3640		       ext4_blocks_count(es), blocks_count);
3641		goto failed_mount;
3642	}
3643
3644	/*
3645	 * It makes no sense for the first data block to be beyond the end
3646	 * of the filesystem.
3647	 */
3648	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3649		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3650			 "block %u is beyond end of filesystem (%llu)",
3651			 le32_to_cpu(es->s_first_data_block),
3652			 ext4_blocks_count(es));
3653		goto failed_mount;
 
 
 
 
 
 
3654	}
 
3655	blocks_count = (ext4_blocks_count(es) -
3656			le32_to_cpu(es->s_first_data_block) +
3657			EXT4_BLOCKS_PER_GROUP(sb) - 1);
3658	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3659	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3660		ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3661		       "(block count %llu, first data block %u, "
3662		       "blocks per group %lu)", sbi->s_groups_count,
3663		       ext4_blocks_count(es),
3664		       le32_to_cpu(es->s_first_data_block),
3665		       EXT4_BLOCKS_PER_GROUP(sb));
3666		goto failed_mount;
3667	}
3668	sbi->s_groups_count = blocks_count;
3669	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3670			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3671	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3672		   EXT4_DESC_PER_BLOCK(sb);
3673	sbi->s_group_desc = ext4_kvmalloc(db_count *
 
 
 
 
 
 
 
 
 
 
3674					  sizeof(struct buffer_head *),
3675					  GFP_KERNEL);
3676	if (sbi->s_group_desc == NULL) {
3677		ext4_msg(sb, KERN_ERR, "not enough memory");
3678		ret = -ENOMEM;
3679		goto failed_mount;
3680	}
3681
3682	if (ext4_proc_root)
3683		sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3684
3685	if (sbi->s_proc)
3686		proc_create_data("options", S_IRUGO, sbi->s_proc,
3687				 &ext4_seq_options_fops, sb);
3688
3689	bgl_lock_init(sbi->s_blockgroup_lock);
3690
 
3691	for (i = 0; i < db_count; i++) {
3692		block = descriptor_loc(sb, logical_sb_block, i);
3693		sbi->s_group_desc[i] = sb_bread(sb, block);
3694		if (!sbi->s_group_desc[i]) {
 
 
 
 
 
 
 
3695			ext4_msg(sb, KERN_ERR,
3696			       "can't read group descriptor %d", i);
3697			db_count = i;
3698			goto failed_mount2;
3699		}
 
 
 
3700	}
3701	if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
 
3702		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3703		goto failed_mount2;
3704	}
3705	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3706		if (!ext4_fill_flex_info(sb)) {
3707			ext4_msg(sb, KERN_ERR,
3708			       "unable to initialize "
3709			       "flex_bg meta info!");
3710			goto failed_mount2;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3711		}
 
3712
3713	sbi->s_gdb_count = db_count;
3714	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3715	spin_lock_init(&sbi->s_next_gen_lock);
 
 
 
 
 
 
 
 
 
3716
3717	init_timer(&sbi->s_err_report);
3718	sbi->s_err_report.function = print_daily_error_info;
3719	sbi->s_err_report.data = (unsigned long) sb;
 
 
 
3720
3721	err = percpu_counter_init(&sbi->s_freeclusters_counter,
3722			ext4_count_free_clusters(sb));
3723	if (!err) {
3724		err = percpu_counter_init(&sbi->s_freeinodes_counter,
3725				ext4_count_free_inodes(sb));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3726	}
3727	if (!err) {
3728		err = percpu_counter_init(&sbi->s_dirs_counter,
3729				ext4_count_dirs(sb));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3730	}
3731	if (!err) {
3732		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
 
 
 
 
 
 
 
 
3733	}
3734	if (err) {
3735		ext4_msg(sb, KERN_ERR, "insufficient memory");
3736		ret = err;
3737		goto failed_mount3;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3738	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3739
3740	sbi->s_stripe = ext4_get_stripe_size(sbi);
3741	sbi->s_max_writeback_mb_bump = 128;
 
 
 
 
 
 
 
3742
3743	/*
3744	 * set up enough so that it can read an inode
3745	 */
3746	if (!test_opt(sb, NOLOAD) &&
3747	    EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3748		sb->s_op = &ext4_sops;
3749	else
3750		sb->s_op = &ext4_nojournal_sops;
3751	sb->s_export_op = &ext4_export_ops;
3752	sb->s_xattr = ext4_xattr_handlers;
 
 
 
 
 
 
3753#ifdef CONFIG_QUOTA
3754	sb->s_qcop = &ext4_qctl_operations;
3755	sb->dq_op = &ext4_quota_operations;
 
 
 
 
 
3756#endif
3757	memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
 
3758
3759	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3760	mutex_init(&sbi->s_orphan_lock);
3761	sbi->s_resize_flags = 0;
 
 
 
 
3762
3763	sb->s_root = NULL;
3764
3765	needs_recovery = (es->s_last_orphan != 0 ||
3766			  EXT4_HAS_INCOMPAT_FEATURE(sb,
3767				    EXT4_FEATURE_INCOMPAT_RECOVER));
3768
3769	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3770	    !(sb->s_flags & MS_RDONLY))
3771		if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3772			goto failed_mount3;
 
3773
 
3774	/*
3775	 * The first inode we look at is the journal inode.  Don't try
3776	 * root first: it may be modified in the journal!
3777	 */
3778	if (!test_opt(sb, NOLOAD) &&
3779	    EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3780		if (ext4_load_journal(sb, es, journal_devnum))
3781			goto failed_mount3;
3782	} else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3783	      EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3784		ext4_msg(sb, KERN_ERR, "required journal recovery "
3785		       "suppressed and not mounted read-only");
3786		goto failed_mount_wq;
3787	} else {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3788		clear_opt(sb, DATA_FLAGS);
 
3789		sbi->s_journal = NULL;
3790		needs_recovery = 0;
3791		goto no_journal;
3792	}
3793
3794	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3795	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3796				       JBD2_FEATURE_INCOMPAT_64BIT)) {
3797		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3798		goto failed_mount_wq;
3799	}
3800
3801	if (!set_journal_csum_feature_set(sb)) {
3802		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3803			 "feature set");
3804		goto failed_mount_wq;
3805	}
3806
3807	/* We have now updated the journal if required, so we can
3808	 * validate the data journaling mode. */
3809	switch (test_opt(sb, DATA_FLAGS)) {
3810	case 0:
3811		/* No mode set, assume a default based on the journal
3812		 * capabilities: ORDERED_DATA if the journal can
3813		 * cope, else JOURNAL_DATA
3814		 */
3815		if (jbd2_journal_check_available_features
3816		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3817			set_opt(sb, ORDERED_DATA);
3818		else
3819			set_opt(sb, JOURNAL_DATA);
3820		break;
3821
3822	case EXT4_MOUNT_ORDERED_DATA:
3823	case EXT4_MOUNT_WRITEBACK_DATA:
3824		if (!jbd2_journal_check_available_features
3825		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3826			ext4_msg(sb, KERN_ERR, "Journal does not support "
3827			       "requested data journaling mode");
3828			goto failed_mount_wq;
3829		}
3830	default:
3831		break;
3832	}
3833	set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3834
3835	sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3836
3837	/*
3838	 * The journal may have updated the bg summary counts, so we
3839	 * need to update the global counters.
3840	 */
3841	percpu_counter_set(&sbi->s_freeclusters_counter,
3842			   ext4_count_free_clusters(sb));
3843	percpu_counter_set(&sbi->s_freeinodes_counter,
3844			   ext4_count_free_inodes(sb));
3845	percpu_counter_set(&sbi->s_dirs_counter,
3846			   ext4_count_dirs(sb));
3847	percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3848
3849no_journal:
3850	/*
3851	 * Get the # of file system overhead blocks from the
3852	 * superblock if present.
3853	 */
3854	if (es->s_overhead_clusters)
3855		sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3856	else {
3857		ret = ext4_calculate_overhead(sb);
3858		if (ret)
 
 
 
 
 
 
 
 
 
3859			goto failed_mount_wq;
3860	}
3861
3862	/*
3863	 * The maximum number of concurrent works can be high and
3864	 * concurrency isn't really necessary.  Limit it to 1.
3865	 */
3866	EXT4_SB(sb)->dio_unwritten_wq =
3867		alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3868	if (!EXT4_SB(sb)->dio_unwritten_wq) {
3869		printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3870		goto failed_mount_wq;
 
3871	}
3872
3873	/*
3874	 * The jbd2_journal_load will have done any necessary log recovery,
3875	 * so we can safely mount the rest of the filesystem now.
3876	 */
3877
3878	root = ext4_iget(sb, EXT4_ROOT_INO);
3879	if (IS_ERR(root)) {
3880		ext4_msg(sb, KERN_ERR, "get root inode failed");
3881		ret = PTR_ERR(root);
3882		root = NULL;
3883		goto failed_mount4;
3884	}
3885	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3886		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3887		iput(root);
 
3888		goto failed_mount4;
3889	}
 
 
3890	sb->s_root = d_make_root(root);
3891	if (!sb->s_root) {
3892		ext4_msg(sb, KERN_ERR, "get root dentry failed");
3893		ret = -ENOMEM;
3894		goto failed_mount4;
3895	}
3896
3897	if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3898		sb->s_flags |= MS_RDONLY;
 
 
 
3899
3900	/* determine the minimum size of new large inodes, if present */
3901	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3902		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3903						     EXT4_GOOD_OLD_INODE_SIZE;
3904		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3905				       EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3906			if (sbi->s_want_extra_isize <
3907			    le16_to_cpu(es->s_want_extra_isize))
3908				sbi->s_want_extra_isize =
3909					le16_to_cpu(es->s_want_extra_isize);
3910			if (sbi->s_want_extra_isize <
3911			    le16_to_cpu(es->s_min_extra_isize))
3912				sbi->s_want_extra_isize =
3913					le16_to_cpu(es->s_min_extra_isize);
3914		}
3915	}
3916	/* Check if enough inode space is available */
3917	if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3918							sbi->s_inode_size) {
3919		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3920						       EXT4_GOOD_OLD_INODE_SIZE;
3921		ext4_msg(sb, KERN_INFO, "required extra inode space not"
3922			 "available");
3923	}
3924
3925	err = ext4_setup_system_zone(sb);
3926	if (err) {
3927		ext4_msg(sb, KERN_ERR, "failed to initialize system "
3928			 "zone (%d)", err);
3929		goto failed_mount4a;
 
 
3930	}
 
3931
3932	ext4_ext_init(sb);
 
 
 
 
 
 
 
 
 
 
 
 
 
3933	err = ext4_mb_init(sb);
3934	if (err) {
3935		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3936			 err);
3937		goto failed_mount5;
3938	}
3939
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3940	err = ext4_register_li_request(sb, first_not_zeroed);
3941	if (err)
3942		goto failed_mount6;
3943
3944	sbi->s_kobj.kset = ext4_kset;
3945	init_completion(&sbi->s_kobj_unregister);
3946	err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3947				   "%s", sb->s_id);
3948	if (err)
3949		goto failed_mount7;
 
 
 
 
 
 
 
 
3950
 
 
 
 
 
 
3951	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3952	ext4_orphan_cleanup(sb, es);
3953	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
 
 
 
 
 
 
 
 
3954	if (needs_recovery) {
3955		ext4_msg(sb, KERN_INFO, "recovery complete");
3956		ext4_mark_recovery_complete(sb, es);
 
 
3957	}
3958	if (EXT4_SB(sb)->s_journal) {
3959		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3960			descr = " journalled data mode";
3961		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3962			descr = " ordered data mode";
3963		else
3964			descr = " writeback data mode";
3965	} else
3966		descr = "out journal";
3967
3968	ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3969		 "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3970		 *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3971
3972	if (es->s_error_count)
3973		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3974
3975	kfree(orig_data);
3976	return 0;
 
 
 
 
3977
3978cantfind_ext4:
3979	if (!silent)
3980		ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3981	goto failed_mount;
 
 
3982
 
 
 
 
3983failed_mount7:
3984	ext4_unregister_li_request(sb);
3985failed_mount6:
3986	ext4_mb_release(sb);
 
 
3987failed_mount5:
3988	ext4_ext_release(sb);
3989	ext4_release_system_zone(sb);
3990failed_mount4a:
3991	dput(sb->s_root);
3992	sb->s_root = NULL;
3993failed_mount4:
3994	ext4_msg(sb, KERN_ERR, "mount failed");
3995	destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
 
3996failed_mount_wq:
 
 
 
 
 
 
3997	if (sbi->s_journal) {
 
 
3998		jbd2_journal_destroy(sbi->s_journal);
3999		sbi->s_journal = NULL;
4000	}
 
 
4001failed_mount3:
4002	del_timer(&sbi->s_err_report);
4003	if (sbi->s_flex_groups)
4004		ext4_kvfree(sbi->s_flex_groups);
4005	percpu_counter_destroy(&sbi->s_freeclusters_counter);
4006	percpu_counter_destroy(&sbi->s_freeinodes_counter);
4007	percpu_counter_destroy(&sbi->s_dirs_counter);
4008	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4009	if (sbi->s_mmp_tsk)
4010		kthread_stop(sbi->s_mmp_tsk);
4011failed_mount2:
4012	for (i = 0; i < db_count; i++)
4013		brelse(sbi->s_group_desc[i]);
4014	ext4_kvfree(sbi->s_group_desc);
4015failed_mount:
4016	if (sbi->s_chksum_driver)
4017		crypto_free_shash(sbi->s_chksum_driver);
4018	if (sbi->s_proc) {
4019		remove_proc_entry("options", sbi->s_proc);
4020		remove_proc_entry(sb->s_id, ext4_proc_root);
4021	}
 
4022#ifdef CONFIG_QUOTA
4023	for (i = 0; i < MAXQUOTAS; i++)
4024		kfree(sbi->s_qf_names[i]);
4025#endif
4026	ext4_blkdev_remove(sbi);
4027	brelse(bh);
 
 
 
 
4028out_fail:
 
4029	sb->s_fs_info = NULL;
4030	kfree(sbi->s_blockgroup_lock);
4031	kfree(sbi);
4032out_free_orig:
4033	kfree(orig_data);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4034	return ret;
4035}
4036
 
 
 
 
 
4037/*
4038 * Setup any per-fs journal parameters now.  We'll do this both on
4039 * initial mount, once the journal has been initialised but before we've
4040 * done any recovery; and again on any subsequent remount.
4041 */
4042static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4043{
4044	struct ext4_sb_info *sbi = EXT4_SB(sb);
4045
4046	journal->j_commit_interval = sbi->s_commit_interval;
4047	journal->j_min_batch_time = sbi->s_min_batch_time;
4048	journal->j_max_batch_time = sbi->s_max_batch_time;
 
4049
4050	write_lock(&journal->j_state_lock);
4051	if (test_opt(sb, BARRIER))
4052		journal->j_flags |= JBD2_BARRIER;
4053	else
4054		journal->j_flags &= ~JBD2_BARRIER;
4055	if (test_opt(sb, DATA_ERR_ABORT))
4056		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4057	else
4058		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
 
 
 
 
 
4059	write_unlock(&journal->j_state_lock);
4060}
4061
4062static journal_t *ext4_get_journal(struct super_block *sb,
4063				   unsigned int journal_inum)
4064{
4065	struct inode *journal_inode;
4066	journal_t *journal;
4067
4068	BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4069
4070	/* First, test for the existence of a valid inode on disk.  Bad
4071	 * things happen if we iget() an unused inode, as the subsequent
4072	 * iput() will try to delete it. */
4073
4074	journal_inode = ext4_iget(sb, journal_inum);
 
 
 
 
 
4075	if (IS_ERR(journal_inode)) {
4076		ext4_msg(sb, KERN_ERR, "no journal found");
4077		return NULL;
4078	}
4079	if (!journal_inode->i_nlink) {
4080		make_bad_inode(journal_inode);
4081		iput(journal_inode);
4082		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4083		return NULL;
4084	}
4085
4086	jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4087		  journal_inode, journal_inode->i_size);
4088	if (!S_ISREG(journal_inode->i_mode)) {
4089		ext4_msg(sb, KERN_ERR, "invalid journal inode");
4090		iput(journal_inode);
4091		return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4092	}
 
 
 
 
 
 
 
 
 
 
 
 
 
4093
4094	journal = jbd2_journal_init_inode(journal_inode);
4095	if (!journal) {
4096		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4097		iput(journal_inode);
4098		return NULL;
4099	}
4100	journal->j_private = sb;
 
4101	ext4_init_journal_params(sb, journal);
4102	return journal;
4103}
4104
4105static journal_t *ext4_get_dev_journal(struct super_block *sb,
4106				       dev_t j_dev)
 
4107{
4108	struct buffer_head *bh;
4109	journal_t *journal;
4110	ext4_fsblk_t start;
4111	ext4_fsblk_t len;
4112	int hblock, blocksize;
4113	ext4_fsblk_t sb_block;
4114	unsigned long offset;
4115	struct ext4_super_block *es;
4116	struct block_device *bdev;
4117
4118	BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4119
4120	bdev = ext4_blkdev_get(j_dev, sb);
4121	if (bdev == NULL)
4122		return NULL;
 
 
 
 
 
 
4123
 
4124	blocksize = sb->s_blocksize;
4125	hblock = bdev_logical_block_size(bdev);
4126	if (blocksize < hblock) {
4127		ext4_msg(sb, KERN_ERR,
4128			"blocksize too small for journal device");
 
4129		goto out_bdev;
4130	}
4131
4132	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4133	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4134	set_blocksize(bdev, blocksize);
4135	if (!(bh = __bread(bdev, sb_block, blocksize))) {
 
4136		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4137		       "external journal");
 
4138		goto out_bdev;
4139	}
4140
4141	es = (struct ext4_super_block *) (bh->b_data + offset);
4142	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4143	    !(le32_to_cpu(es->s_feature_incompat) &
4144	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4145		ext4_msg(sb, KERN_ERR, "external journal has "
4146					"bad superblock");
4147		brelse(bh);
4148		goto out_bdev;
 
 
 
 
 
 
 
4149	}
4150
4151	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4152		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4153		brelse(bh);
4154		goto out_bdev;
4155	}
4156
4157	len = ext4_blocks_count(es);
4158	start = sb_block + 1;
4159	brelse(bh);	/* we're done with the superblock */
4160
4161	journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4162					start, len, blocksize);
4163	if (!journal) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4164		ext4_msg(sb, KERN_ERR, "failed to create device journal");
 
4165		goto out_bdev;
4166	}
4167	journal->j_private = sb;
4168	ll_rw_block(READ, 1, &journal->j_sb_buffer);
4169	wait_on_buffer(journal->j_sb_buffer);
4170	if (!buffer_uptodate(journal->j_sb_buffer)) {
4171		ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4172		goto out_journal;
4173	}
4174	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4175		ext4_msg(sb, KERN_ERR, "External journal has more than one "
4176					"user (unsupported) - %d",
4177			be32_to_cpu(journal->j_superblock->s_nr_users));
 
4178		goto out_journal;
4179	}
4180	EXT4_SB(sb)->journal_bdev = bdev;
 
4181	ext4_init_journal_params(sb, journal);
4182	return journal;
4183
4184out_journal:
4185	jbd2_journal_destroy(journal);
4186out_bdev:
4187	ext4_blkdev_put(bdev);
4188	return NULL;
4189}
4190
4191static int ext4_load_journal(struct super_block *sb,
4192			     struct ext4_super_block *es,
4193			     unsigned long journal_devnum)
4194{
4195	journal_t *journal;
4196	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4197	dev_t journal_dev;
4198	int err = 0;
4199	int really_read_only;
 
4200
4201	BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
 
4202
4203	if (journal_devnum &&
4204	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4205		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4206			"numbers have changed");
4207		journal_dev = new_decode_dev(journal_devnum);
4208	} else
4209		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4210
4211	really_read_only = bdev_read_only(sb->s_bdev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4212
4213	/*
4214	 * Are we loading a blank journal or performing recovery after a
4215	 * crash?  For recovery, we need to check in advance whether we
4216	 * can get read-write access to the device.
4217	 */
4218	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4219		if (sb->s_flags & MS_RDONLY) {
4220			ext4_msg(sb, KERN_INFO, "INFO: recovery "
4221					"required on readonly filesystem");
4222			if (really_read_only) {
4223				ext4_msg(sb, KERN_ERR, "write access "
4224					"unavailable, cannot proceed");
4225				return -EROFS;
 
 
4226			}
4227			ext4_msg(sb, KERN_INFO, "write access will "
4228			       "be enabled during recovery");
4229		}
4230	}
4231
4232	if (journal_inum && journal_dev) {
4233		ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4234		       "and inode journals!");
4235		return -EINVAL;
4236	}
4237
4238	if (journal_inum) {
4239		if (!(journal = ext4_get_journal(sb, journal_inum)))
4240			return -EINVAL;
4241	} else {
4242		if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4243			return -EINVAL;
4244	}
4245
4246	if (!(journal->j_flags & JBD2_BARRIER))
4247		ext4_msg(sb, KERN_INFO, "barriers disabled");
4248
4249	if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4250		err = jbd2_journal_wipe(journal, !really_read_only);
4251	if (!err) {
4252		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
 
 
 
4253		if (save)
4254			memcpy(save, ((char *) es) +
4255			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4256		err = jbd2_journal_load(journal);
4257		if (save)
 
4258			memcpy(((char *) es) + EXT4_S_ERR_START,
4259			       save, EXT4_S_ERR_LEN);
 
 
4260		kfree(save);
 
 
 
 
 
 
 
 
 
 
 
4261	}
4262
4263	if (err) {
4264		ext4_msg(sb, KERN_ERR, "error loading journal");
4265		jbd2_journal_destroy(journal);
4266		return err;
4267	}
4268
4269	EXT4_SB(sb)->s_journal = journal;
4270	ext4_clear_journal_err(sb, es);
 
 
 
 
 
4271
4272	if (!really_read_only && journal_devnum &&
4273	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4274		es->s_journal_dev = cpu_to_le32(journal_devnum);
4275
4276		/* Make sure we flush the recovery flag to disk. */
4277		ext4_commit_super(sb, 1);
 
 
 
4278	}
4279
4280	return 0;
 
 
 
 
4281}
4282
4283static int ext4_commit_super(struct super_block *sb, int sync)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4284{
4285	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4286	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4287	int error = 0;
4288
4289	if (!sbh || block_device_ejected(sb))
4290		return error;
4291	if (buffer_write_io_error(sbh)) {
 
 
 
 
 
 
 
 
 
 
4292		/*
4293		 * Oh, dear.  A previous attempt to write the
4294		 * superblock failed.  This could happen because the
4295		 * USB device was yanked out.  Or it could happen to
4296		 * be a transient write error and maybe the block will
4297		 * be remapped.  Nothing we can do but to retry the
4298		 * write and hope for the best.
4299		 */
4300		ext4_msg(sb, KERN_ERR, "previous I/O error to "
4301		       "superblock detected");
4302		clear_buffer_write_io_error(sbh);
4303		set_buffer_uptodate(sbh);
4304	}
4305	/*
4306	 * If the file system is mounted read-only, don't update the
4307	 * superblock write time.  This avoids updating the superblock
4308	 * write time when we are mounting the root file system
4309	 * read/only but we need to replay the journal; at that point,
4310	 * for people who are east of GMT and who make their clock
4311	 * tick in localtime for Windows bug-for-bug compatibility,
4312	 * the clock is set in the future, and this will cause e2fsck
4313	 * to complain and force a full file system check.
4314	 */
4315	if (!(sb->s_flags & MS_RDONLY))
4316		es->s_wtime = cpu_to_le32(get_seconds());
4317	if (sb->s_bdev->bd_part)
4318		es->s_kbytes_written =
4319			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4320			    ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4321			      EXT4_SB(sb)->s_sectors_written_start) >> 1));
4322	else
4323		es->s_kbytes_written =
4324			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4325	ext4_free_blocks_count_set(es,
4326			EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4327				&EXT4_SB(sb)->s_freeclusters_counter)));
4328	es->s_free_inodes_count =
4329		cpu_to_le32(percpu_counter_sum_positive(
4330				&EXT4_SB(sb)->s_freeinodes_counter));
4331	sb->s_dirt = 0;
4332	BUFFER_TRACE(sbh, "marking dirty");
4333	ext4_superblock_csum_set(sb, es);
4334	mark_buffer_dirty(sbh);
4335	if (sync) {
4336		error = sync_dirty_buffer(sbh);
4337		if (error)
4338			return error;
4339
4340		error = buffer_write_io_error(sbh);
4341		if (error) {
4342			ext4_msg(sb, KERN_ERR, "I/O error while writing "
4343			       "superblock");
4344			clear_buffer_write_io_error(sbh);
4345			set_buffer_uptodate(sbh);
4346		}
4347	}
4348	return error;
4349}
4350
4351/*
4352 * Have we just finished recovery?  If so, and if we are mounting (or
4353 * remounting) the filesystem readonly, then we will end up with a
4354 * consistent fs on disk.  Record that fact.
4355 */
4356static void ext4_mark_recovery_complete(struct super_block *sb,
4357					struct ext4_super_block *es)
4358{
 
4359	journal_t *journal = EXT4_SB(sb)->s_journal;
4360
4361	if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4362		BUG_ON(journal != NULL);
4363		return;
 
 
 
 
4364	}
4365	jbd2_journal_lock_updates(journal);
4366	if (jbd2_journal_flush(journal) < 0)
 
4367		goto out;
4368
4369	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4370	    sb->s_flags & MS_RDONLY) {
4371		EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4372		ext4_commit_super(sb, 1);
 
 
 
 
 
 
4373	}
4374
4375out:
4376	jbd2_journal_unlock_updates(journal);
 
4377}
4378
4379/*
4380 * If we are mounting (or read-write remounting) a filesystem whose journal
4381 * has recorded an error from a previous lifetime, move that error to the
4382 * main filesystem now.
4383 */
4384static void ext4_clear_journal_err(struct super_block *sb,
4385				   struct ext4_super_block *es)
4386{
4387	journal_t *journal;
4388	int j_errno;
4389	const char *errstr;
4390
4391	BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
 
 
 
4392
4393	journal = EXT4_SB(sb)->s_journal;
4394
4395	/*
4396	 * Now check for any error status which may have been recorded in the
4397	 * journal by a prior ext4_error() or ext4_abort()
4398	 */
4399
4400	j_errno = jbd2_journal_errno(journal);
4401	if (j_errno) {
4402		char nbuf[16];
4403
4404		errstr = ext4_decode_error(sb, j_errno, nbuf);
4405		ext4_warning(sb, "Filesystem error recorded "
4406			     "from previous mount: %s", errstr);
4407		ext4_warning(sb, "Marking fs in need of filesystem check.");
4408
4409		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4410		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4411		ext4_commit_super(sb, 1);
 
 
 
4412
4413		jbd2_journal_clear_err(journal);
4414		jbd2_journal_update_sb_errno(journal);
4415	}
 
4416}
4417
4418/*
4419 * Force the running and committing transactions to commit,
4420 * and wait on the commit.
4421 */
4422int ext4_force_commit(struct super_block *sb)
4423{
4424	journal_t *journal;
4425	int ret = 0;
4426
4427	if (sb->s_flags & MS_RDONLY)
4428		return 0;
4429
4430	journal = EXT4_SB(sb)->s_journal;
4431	if (journal) {
4432		vfs_check_frozen(sb, SB_FREEZE_TRANS);
4433		ret = ext4_journal_force_commit(journal);
4434	}
4435
4436	return ret;
4437}
4438
4439static void ext4_write_super(struct super_block *sb)
4440{
4441	lock_super(sb);
4442	ext4_commit_super(sb, 1);
4443	unlock_super(sb);
4444}
4445
4446static int ext4_sync_fs(struct super_block *sb, int wait)
4447{
4448	int ret = 0;
4449	tid_t target;
 
4450	struct ext4_sb_info *sbi = EXT4_SB(sb);
4451
 
 
 
4452	trace_ext4_sync_fs(sb, wait);
4453	flush_workqueue(sbi->dio_unwritten_wq);
4454	if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4455		if (wait)
4456			jbd2_log_wait_commit(sbi->s_journal, target);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4457	}
 
4458	return ret;
4459}
4460
4461/*
4462 * LVM calls this function before a (read-only) snapshot is created.  This
4463 * gives us a chance to flush the journal completely and mark the fs clean.
4464 *
4465 * Note that only this function cannot bring a filesystem to be in a clean
4466 * state independently, because ext4 prevents a new handle from being started
4467 * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4468 * the upper layer.
4469 */
4470static int ext4_freeze(struct super_block *sb)
4471{
4472	int error = 0;
4473	journal_t *journal;
4474
4475	if (sb->s_flags & MS_RDONLY)
4476		return 0;
4477
4478	journal = EXT4_SB(sb)->s_journal;
 
 
4479
4480	/* Now we set up the journal barrier. */
4481	jbd2_journal_lock_updates(journal);
 
 
 
 
 
4482
4483	/*
4484	 * Don't clear the needs_recovery flag if we failed to flush
4485	 * the journal.
4486	 */
4487	error = jbd2_journal_flush(journal);
4488	if (error < 0)
4489		goto out;
4490
4491	/* Journal blocked and flushed, clear needs_recovery flag. */
4492	EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4493	error = ext4_commit_super(sb, 1);
4494out:
4495	/* we rely on s_frozen to stop further updates */
4496	jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 
4497	return error;
4498}
4499
4500/*
4501 * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4502 * flag here, even though the filesystem is not technically dirty yet.
4503 */
4504static int ext4_unfreeze(struct super_block *sb)
4505{
4506	if (sb->s_flags & MS_RDONLY)
4507		return 0;
4508
4509	lock_super(sb);
4510	/* Reset the needs_recovery flag before the fs is unlocked. */
4511	EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4512	ext4_commit_super(sb, 1);
4513	unlock_super(sb);
 
 
 
4514	return 0;
4515}
4516
4517/*
4518 * Structure to save mount options for ext4_remount's benefit
4519 */
4520struct ext4_mount_options {
4521	unsigned long s_mount_opt;
4522	unsigned long s_mount_opt2;
4523	kuid_t s_resuid;
4524	kgid_t s_resgid;
4525	unsigned long s_commit_interval;
4526	u32 s_min_batch_time, s_max_batch_time;
4527#ifdef CONFIG_QUOTA
4528	int s_jquota_fmt;
4529	char *s_qf_names[MAXQUOTAS];
4530#endif
4531};
4532
4533static int ext4_remount(struct super_block *sb, int *flags, char *data)
4534{
 
4535	struct ext4_super_block *es;
4536	struct ext4_sb_info *sbi = EXT4_SB(sb);
4537	unsigned long old_sb_flags;
4538	struct ext4_mount_options old_opts;
4539	int enable_quota = 0;
4540	ext4_group_t g;
4541	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4542	int err = 0;
 
4543#ifdef CONFIG_QUOTA
4544	int i;
 
 
4545#endif
4546	char *orig_data = kstrdup(data, GFP_KERNEL);
4547
4548	/* Store the original options */
4549	lock_super(sb);
4550	old_sb_flags = sb->s_flags;
4551	old_opts.s_mount_opt = sbi->s_mount_opt;
4552	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4553	old_opts.s_resuid = sbi->s_resuid;
4554	old_opts.s_resgid = sbi->s_resgid;
4555	old_opts.s_commit_interval = sbi->s_commit_interval;
4556	old_opts.s_min_batch_time = sbi->s_min_batch_time;
4557	old_opts.s_max_batch_time = sbi->s_max_batch_time;
4558#ifdef CONFIG_QUOTA
4559	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4560	for (i = 0; i < MAXQUOTAS; i++)
4561		old_opts.s_qf_names[i] = sbi->s_qf_names[i];
 
 
 
 
 
 
 
 
 
 
4562#endif
4563	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4564		journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4565
4566	/*
4567	 * Allow the "check" option to be passed as a remount option.
 
 
 
 
4568	 */
4569	if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4570		err = -EINVAL;
4571		goto restore_opts;
4572	}
4573
4574	if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4575		ext4_abort(sb, "Abort forced by user");
 
 
 
 
4576
4577	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4578		(test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4579
4580	es = sbi->s_es;
4581
4582	if (sbi->s_journal) {
4583		ext4_init_journal_params(sb, sbi->s_journal);
4584		set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4585	}
4586
4587	if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4588		if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
 
 
 
4589			err = -EROFS;
4590			goto restore_opts;
4591		}
4592
4593		if (*flags & MS_RDONLY) {
 
 
 
4594			err = dquot_suspend(sb, -1);
4595			if (err < 0)
4596				goto restore_opts;
4597
4598			/*
4599			 * First of all, the unconditional stuff we have to do
4600			 * to disable replay of the journal when we next remount
4601			 */
4602			sb->s_flags |= MS_RDONLY;
4603
4604			/*
4605			 * OK, test if we are remounting a valid rw partition
4606			 * readonly, and if so set the rdonly flag and then
4607			 * mark the partition as valid again.
4608			 */
4609			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4610			    (sbi->s_mount_state & EXT4_VALID_FS))
4611				es->s_state = cpu_to_le16(sbi->s_mount_state);
4612
4613			if (sbi->s_journal)
 
 
 
 
4614				ext4_mark_recovery_complete(sb, es);
 
4615		} else {
4616			/* Make sure we can mount this feature set readwrite */
4617			if (!ext4_feature_set_ok(sb, 0)) {
 
4618				err = -EROFS;
4619				goto restore_opts;
4620			}
4621			/*
4622			 * Make sure the group descriptor checksums
4623			 * are sane.  If they aren't, refuse to remount r/w.
4624			 */
4625			for (g = 0; g < sbi->s_groups_count; g++) {
4626				struct ext4_group_desc *gdp =
4627					ext4_get_group_desc(sb, g, NULL);
4628
4629				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4630					ext4_msg(sb, KERN_ERR,
4631	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
4632		g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4633					       le16_to_cpu(gdp->bg_checksum));
4634					err = -EINVAL;
4635					goto restore_opts;
4636				}
4637			}
4638
4639			/*
4640			 * If we have an unprocessed orphan list hanging
4641			 * around from a previously readonly bdev mount,
4642			 * require a full umount/remount for now.
4643			 */
4644			if (es->s_last_orphan) {
4645				ext4_msg(sb, KERN_WARNING, "Couldn't "
4646				       "remount RDWR because of unprocessed "
4647				       "orphan inode list.  Please "
4648				       "umount/remount instead");
4649				err = -EINVAL;
4650				goto restore_opts;
4651			}
4652
4653			/*
4654			 * Mounting a RDONLY partition read-write, so reread
4655			 * and store the current valid flag.  (It may have
4656			 * been changed by e2fsck since we originally mounted
4657			 * the partition.)
4658			 */
4659			if (sbi->s_journal)
4660				ext4_clear_journal_err(sb, es);
4661			sbi->s_mount_state = le16_to_cpu(es->s_state);
4662			if (!ext4_setup_super(sb, es, 0))
4663				sb->s_flags &= ~MS_RDONLY;
4664			if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4665						     EXT4_FEATURE_INCOMPAT_MMP))
4666				if (ext4_multi_mount_protect(sb,
4667						le64_to_cpu(es->s_mmp_block))) {
4668					err = -EROFS;
4669					goto restore_opts;
4670				}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4671			enable_quota = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4672		}
4673	}
 
 
 
 
 
 
4674
4675	/*
4676	 * Reinitialize lazy itable initialization thread based on
4677	 * current settings
4678	 */
4679	if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4680		ext4_unregister_li_request(sb);
4681	else {
4682		ext4_group_t first_not_zeroed;
4683		first_not_zeroed = ext4_has_uninit_itable(sb);
4684		ext4_register_li_request(sb, first_not_zeroed);
4685	}
4686
4687	ext4_setup_system_zone(sb);
4688	if (sbi->s_journal == NULL)
4689		ext4_commit_super(sb, 1);
4690
4691#ifdef CONFIG_QUOTA
4692	/* Release old quota file names */
4693	for (i = 0; i < MAXQUOTAS; i++)
4694		if (old_opts.s_qf_names[i] &&
4695		    old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4696			kfree(old_opts.s_qf_names[i]);
4697#endif
4698	unlock_super(sb);
4699	if (enable_quota)
4700		dquot_resume(sb, -1);
4701
4702	ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4703	kfree(orig_data);
4704	return 0;
4705
4706restore_opts:
 
 
 
 
 
 
 
 
 
4707	sb->s_flags = old_sb_flags;
4708	sbi->s_mount_opt = old_opts.s_mount_opt;
4709	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4710	sbi->s_resuid = old_opts.s_resuid;
4711	sbi->s_resgid = old_opts.s_resgid;
4712	sbi->s_commit_interval = old_opts.s_commit_interval;
4713	sbi->s_min_batch_time = old_opts.s_min_batch_time;
4714	sbi->s_max_batch_time = old_opts.s_max_batch_time;
 
 
 
 
4715#ifdef CONFIG_QUOTA
4716	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4717	for (i = 0; i < MAXQUOTAS; i++) {
4718		if (sbi->s_qf_names[i] &&
4719		    old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4720			kfree(sbi->s_qf_names[i]);
4721		sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4722	}
 
4723#endif
4724	unlock_super(sb);
4725	kfree(orig_data);
4726	return err;
4727}
4728
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4729static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4730{
4731	struct super_block *sb = dentry->d_sb;
4732	struct ext4_sb_info *sbi = EXT4_SB(sb);
4733	struct ext4_super_block *es = sbi->s_es;
4734	ext4_fsblk_t overhead = 0;
4735	u64 fsid;
4736	s64 bfree;
 
4737
4738	if (!test_opt(sb, MINIX_DF))
4739		overhead = sbi->s_overhead;
4740
4741	buf->f_type = EXT4_SUPER_MAGIC;
4742	buf->f_bsize = sb->s_blocksize;
4743	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, sbi->s_overhead);
4744	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4745		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4746	/* prevent underflow in case that few free space is available */
4747	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4748	buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4749	if (buf->f_bfree < ext4_r_blocks_count(es))
 
4750		buf->f_bavail = 0;
4751	buf->f_files = le32_to_cpu(es->s_inodes_count);
4752	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4753	buf->f_namelen = EXT4_NAME_LEN;
4754	fsid = le64_to_cpup((void *)es->s_uuid) ^
4755	       le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4756	buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4757	buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4758
 
 
 
 
 
4759	return 0;
4760}
4761
4762/* Helper function for writing quotas on sync - we need to start transaction
4763 * before quota file is locked for write. Otherwise the are possible deadlocks:
4764 * Process 1                         Process 2
4765 * ext4_create()                     quota_sync()
4766 *   jbd2_journal_start()                  write_dquot()
4767 *   dquot_initialize()                         down(dqio_mutex)
4768 *     down(dqio_mutex)                    jbd2_journal_start()
4769 *
4770 */
4771
4772#ifdef CONFIG_QUOTA
4773
 
 
 
 
4774static inline struct inode *dquot_to_inode(struct dquot *dquot)
4775{
4776	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4777}
4778
4779static int ext4_write_dquot(struct dquot *dquot)
4780{
4781	int ret, err;
4782	handle_t *handle;
4783	struct inode *inode;
4784
4785	inode = dquot_to_inode(dquot);
4786	handle = ext4_journal_start(inode,
4787				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4788	if (IS_ERR(handle))
4789		return PTR_ERR(handle);
4790	ret = dquot_commit(dquot);
 
 
 
 
4791	err = ext4_journal_stop(handle);
4792	if (!ret)
4793		ret = err;
4794	return ret;
4795}
4796
4797static int ext4_acquire_dquot(struct dquot *dquot)
4798{
4799	int ret, err;
4800	handle_t *handle;
4801
4802	handle = ext4_journal_start(dquot_to_inode(dquot),
4803				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4804	if (IS_ERR(handle))
4805		return PTR_ERR(handle);
4806	ret = dquot_acquire(dquot);
 
 
 
 
4807	err = ext4_journal_stop(handle);
4808	if (!ret)
4809		ret = err;
4810	return ret;
4811}
4812
4813static int ext4_release_dquot(struct dquot *dquot)
4814{
4815	int ret, err;
4816	handle_t *handle;
4817
4818	handle = ext4_journal_start(dquot_to_inode(dquot),
4819				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4820	if (IS_ERR(handle)) {
4821		/* Release dquot anyway to avoid endless cycle in dqput() */
4822		dquot_release(dquot);
4823		return PTR_ERR(handle);
4824	}
4825	ret = dquot_release(dquot);
 
 
 
 
4826	err = ext4_journal_stop(handle);
4827	if (!ret)
4828		ret = err;
4829	return ret;
4830}
4831
4832static int ext4_mark_dquot_dirty(struct dquot *dquot)
4833{
4834	/* Are we journaling quotas? */
4835	if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4836	    EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4837		dquot_mark_dquot_dirty(dquot);
4838		return ext4_write_dquot(dquot);
4839	} else {
4840		return dquot_mark_dquot_dirty(dquot);
4841	}
4842}
4843
4844static int ext4_write_info(struct super_block *sb, int type)
4845{
4846	int ret, err;
4847	handle_t *handle;
4848
4849	/* Data block + inode block */
4850	handle = ext4_journal_start(sb->s_root->d_inode, 2);
4851	if (IS_ERR(handle))
4852		return PTR_ERR(handle);
4853	ret = dquot_commit_info(sb, type);
4854	err = ext4_journal_stop(handle);
4855	if (!ret)
4856		ret = err;
4857	return ret;
4858}
4859
4860/*
4861 * Turn on quotas during mount time - we need to find
4862 * the quota file and such...
4863 */
4864static int ext4_quota_on_mount(struct super_block *sb, int type)
4865{
4866	return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4867					EXT4_SB(sb)->s_jquota_fmt, type);
 
 
 
 
 
 
 
 
4868}
4869
4870/*
4871 * Standard function to be called on quota_on
4872 */
4873static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4874			 struct path *path)
4875{
4876	int err;
4877
4878	if (!test_opt(sb, QUOTA))
4879		return -EINVAL;
4880
4881	/* Quotafile not on the same filesystem? */
4882	if (path->dentry->d_sb != sb)
4883		return -EXDEV;
 
 
 
 
 
4884	/* Journaling quota? */
4885	if (EXT4_SB(sb)->s_qf_names[type]) {
4886		/* Quotafile not in fs root? */
4887		if (path->dentry->d_parent != sb->s_root)
4888			ext4_msg(sb, KERN_WARNING,
4889				"Quota file not on filesystem root. "
4890				"Journaled quota will not work");
 
 
 
 
 
 
 
4891	}
4892
4893	/*
4894	 * When we journal data on quota file, we have to flush journal to see
4895	 * all updates to the file when we bypass pagecache...
4896	 */
4897	if (EXT4_SB(sb)->s_journal &&
4898	    ext4_should_journal_data(path->dentry->d_inode)) {
4899		/*
4900		 * We don't need to lock updates but journal_flush() could
4901		 * otherwise be livelocked...
 
4902		 */
4903		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4904		err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4905		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
 
 
 
 
 
 
 
 
4906		if (err)
4907			return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4908	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4909
4910	return dquot_quota_on(sb, type, format_id, path);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4911}
4912
4913static int ext4_quota_off(struct super_block *sb, int type)
4914{
4915	struct inode *inode = sb_dqopt(sb)->files[type];
4916	handle_t *handle;
 
4917
4918	/* Force all delayed allocation blocks to be allocated.
4919	 * Caller already holds s_umount sem */
4920	if (test_opt(sb, DELALLOC))
4921		sync_filesystem(sb);
4922
4923	if (!inode)
4924		goto out;
4925
4926	/* Update modification times of quota files when userspace can
4927	 * start looking at them */
4928	handle = ext4_journal_start(inode, 1);
4929	if (IS_ERR(handle))
4930		goto out;
4931	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4932	ext4_mark_inode_dirty(handle, inode);
4933	ext4_journal_stop(handle);
 
 
4934
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4935out:
4936	return dquot_quota_off(sb, type);
4937}
4938
4939/* Read data from quotafile - avoid pagecache and such because we cannot afford
4940 * acquiring the locks... As quota files are never truncated and quota code
4941 * itself serializes the operations (and no one else should touch the files)
4942 * we don't have to be afraid of races */
4943static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4944			       size_t len, loff_t off)
4945{
4946	struct inode *inode = sb_dqopt(sb)->files[type];
4947	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4948	int err = 0;
4949	int offset = off & (sb->s_blocksize - 1);
4950	int tocopy;
4951	size_t toread;
4952	struct buffer_head *bh;
4953	loff_t i_size = i_size_read(inode);
4954
4955	if (off > i_size)
4956		return 0;
4957	if (off+len > i_size)
4958		len = i_size-off;
4959	toread = len;
4960	while (toread > 0) {
4961		tocopy = sb->s_blocksize - offset < toread ?
4962				sb->s_blocksize - offset : toread;
4963		bh = ext4_bread(NULL, inode, blk, 0, &err);
4964		if (err)
4965			return err;
4966		if (!bh)	/* A hole? */
4967			memset(data, 0, tocopy);
4968		else
4969			memcpy(data, bh->b_data+offset, tocopy);
4970		brelse(bh);
4971		offset = 0;
4972		toread -= tocopy;
4973		data += tocopy;
4974		blk++;
4975	}
4976	return len;
4977}
4978
4979/* Write to quotafile (we know the transaction is already started and has
4980 * enough credits) */
4981static ssize_t ext4_quota_write(struct super_block *sb, int type,
4982				const char *data, size_t len, loff_t off)
4983{
4984	struct inode *inode = sb_dqopt(sb)->files[type];
4985	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4986	int err = 0;
4987	int offset = off & (sb->s_blocksize - 1);
4988	struct buffer_head *bh;
4989	handle_t *handle = journal_current_handle();
4990
4991	if (EXT4_SB(sb)->s_journal && !handle) {
4992		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4993			" cancelled because transaction is not started",
4994			(unsigned long long)off, (unsigned long long)len);
4995		return -EIO;
4996	}
4997	/*
4998	 * Since we account only one data block in transaction credits,
4999	 * then it is impossible to cross a block boundary.
5000	 */
5001	if (sb->s_blocksize - offset < len) {
5002		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5003			" cancelled because not block aligned",
5004			(unsigned long long)off, (unsigned long long)len);
5005		return -EIO;
5006	}
5007
5008	bh = ext4_bread(handle, inode, blk, 1, &err);
 
 
 
 
 
 
 
5009	if (!bh)
5010		goto out;
5011	err = ext4_journal_get_write_access(handle, bh);
 
5012	if (err) {
5013		brelse(bh);
5014		goto out;
5015	}
5016	lock_buffer(bh);
5017	memcpy(bh->b_data+offset, data, len);
5018	flush_dcache_page(bh->b_page);
5019	unlock_buffer(bh);
5020	err = ext4_handle_dirty_metadata(handle, NULL, bh);
5021	brelse(bh);
5022out:
5023	if (err)
5024		return err;
5025	if (inode->i_size < off + len) {
5026		i_size_write(inode, off + len);
5027		EXT4_I(inode)->i_disksize = inode->i_size;
5028		ext4_mark_inode_dirty(handle, inode);
 
 
5029	}
5030	return len;
5031}
5032
5033#endif
5034
5035static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5036		       const char *dev_name, void *data)
5037{
5038	return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5039}
5040
5041#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5042static inline void register_as_ext2(void)
5043{
5044	int err = register_filesystem(&ext2_fs_type);
5045	if (err)
5046		printk(KERN_WARNING
5047		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5048}
5049
5050static inline void unregister_as_ext2(void)
5051{
5052	unregister_filesystem(&ext2_fs_type);
5053}
5054
5055static inline int ext2_feature_set_ok(struct super_block *sb)
5056{
5057	if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5058		return 0;
5059	if (sb->s_flags & MS_RDONLY)
5060		return 1;
5061	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5062		return 0;
5063	return 1;
5064}
5065MODULE_ALIAS("ext2");
5066#else
5067static inline void register_as_ext2(void) { }
5068static inline void unregister_as_ext2(void) { }
5069static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5070#endif
5071
5072#if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5073static inline void register_as_ext3(void)
5074{
5075	int err = register_filesystem(&ext3_fs_type);
5076	if (err)
5077		printk(KERN_WARNING
5078		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5079}
5080
5081static inline void unregister_as_ext3(void)
5082{
5083	unregister_filesystem(&ext3_fs_type);
5084}
5085
5086static inline int ext3_feature_set_ok(struct super_block *sb)
5087{
5088	if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5089		return 0;
5090	if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5091		return 0;
5092	if (sb->s_flags & MS_RDONLY)
5093		return 1;
5094	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5095		return 0;
5096	return 1;
5097}
5098MODULE_ALIAS("ext3");
5099#else
5100static inline void register_as_ext3(void) { }
5101static inline void unregister_as_ext3(void) { }
5102static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5103#endif
5104
5105static struct file_system_type ext4_fs_type = {
5106	.owner		= THIS_MODULE,
5107	.name		= "ext4",
5108	.mount		= ext4_mount,
5109	.kill_sb	= kill_block_super,
5110	.fs_flags	= FS_REQUIRES_DEV,
5111};
5112
5113static int __init ext4_init_feat_adverts(void)
5114{
5115	struct ext4_features *ef;
5116	int ret = -ENOMEM;
5117
5118	ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5119	if (!ef)
5120		goto out;
5121
5122	ef->f_kobj.kset = ext4_kset;
5123	init_completion(&ef->f_kobj_unregister);
5124	ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5125				   "features");
5126	if (ret) {
5127		kfree(ef);
5128		goto out;
5129	}
5130
5131	ext4_feat = ef;
5132	ret = 0;
5133out:
5134	return ret;
5135}
5136
5137static void ext4_exit_feat_adverts(void)
5138{
5139	kobject_put(&ext4_feat->f_kobj);
5140	wait_for_completion(&ext4_feat->f_kobj_unregister);
5141	kfree(ext4_feat);
5142}
 
 
 
5143
5144/* Shared across all ext4 file systems */
5145wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5146struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5147
5148static int __init ext4_init_fs(void)
5149{
5150	int i, err;
5151
 
5152	ext4_li_info = NULL;
5153	mutex_init(&ext4_li_mtx);
5154
 
5155	ext4_check_flag_values();
5156
5157	for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5158		mutex_init(&ext4__aio_mutex[i]);
5159		init_waitqueue_head(&ext4__ioend_wq[i]);
5160	}
5161
5162	err = ext4_init_pageio();
5163	if (err)
5164		return err;
5165	err = ext4_init_system_zone();
 
 
 
 
 
5166	if (err)
5167		goto out6;
5168	ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5169	if (!ext4_kset)
 
5170		goto out5;
5171	ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5172
5173	err = ext4_init_feat_adverts();
5174	if (err)
5175		goto out4;
5176
5177	err = ext4_init_mballoc();
5178	if (err)
5179		goto out3;
5180
5181	err = ext4_init_xattr();
5182	if (err)
5183		goto out2;
5184	err = init_inodecache();
5185	if (err)
5186		goto out1;
 
 
 
 
 
5187	register_as_ext3();
5188	register_as_ext2();
5189	err = register_filesystem(&ext4_fs_type);
5190	if (err)
5191		goto out;
5192
5193	return 0;
5194out:
5195	unregister_as_ext2();
5196	unregister_as_ext3();
 
 
5197	destroy_inodecache();
5198out1:
5199	ext4_exit_xattr();
5200out2:
5201	ext4_exit_mballoc();
 
 
5202out3:
5203	ext4_exit_feat_adverts();
5204out4:
5205	if (ext4_proc_root)
5206		remove_proc_entry("fs/ext4", NULL);
5207	kset_unregister(ext4_kset);
5208out5:
5209	ext4_exit_system_zone();
5210out6:
5211	ext4_exit_pageio();
 
 
 
5212	return err;
5213}
5214
5215static void __exit ext4_exit_fs(void)
5216{
5217	ext4_destroy_lazyinit_thread();
5218	unregister_as_ext2();
5219	unregister_as_ext3();
5220	unregister_filesystem(&ext4_fs_type);
 
5221	destroy_inodecache();
5222	ext4_exit_xattr();
5223	ext4_exit_mballoc();
5224	ext4_exit_feat_adverts();
5225	remove_proc_entry("fs/ext4", NULL);
5226	kset_unregister(ext4_kset);
5227	ext4_exit_system_zone();
5228	ext4_exit_pageio();
 
 
 
5229}
5230
5231MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5232MODULE_DESCRIPTION("Fourth Extended Filesystem");
5233MODULE_LICENSE("GPL");
 
5234module_init(ext4_init_fs)
5235module_exit(ext4_exit_fs)