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v4.17
   1/*
   2 * inode.c - NILFS inode operations.
   3 *
   4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * Written by Ryusuke Konishi.
 
 
 
 
  17 *
  18 */
  19
  20#include <linux/buffer_head.h>
  21#include <linux/gfp.h>
  22#include <linux/mpage.h>
  23#include <linux/pagemap.h>
  24#include <linux/writeback.h>
  25#include <linux/uio.h>
  26#include "nilfs.h"
  27#include "btnode.h"
  28#include "segment.h"
  29#include "page.h"
  30#include "mdt.h"
  31#include "cpfile.h"
  32#include "ifile.h"
  33
  34/**
  35 * struct nilfs_iget_args - arguments used during comparison between inodes
  36 * @ino: inode number
  37 * @cno: checkpoint number
  38 * @root: pointer on NILFS root object (mounted checkpoint)
  39 * @for_gc: inode for GC flag
  40 */
  41struct nilfs_iget_args {
  42	u64 ino;
  43	__u64 cno;
  44	struct nilfs_root *root;
  45	int for_gc;
  46};
  47
  48static int nilfs_iget_test(struct inode *inode, void *opaque);
  49
  50void nilfs_inode_add_blocks(struct inode *inode, int n)
  51{
  52	struct nilfs_root *root = NILFS_I(inode)->i_root;
  53
  54	inode_add_bytes(inode, i_blocksize(inode) * n);
  55	if (root)
  56		atomic64_add(n, &root->blocks_count);
  57}
  58
  59void nilfs_inode_sub_blocks(struct inode *inode, int n)
  60{
  61	struct nilfs_root *root = NILFS_I(inode)->i_root;
  62
  63	inode_sub_bytes(inode, i_blocksize(inode) * n);
  64	if (root)
  65		atomic64_sub(n, &root->blocks_count);
  66}
  67
  68/**
  69 * nilfs_get_block() - get a file block on the filesystem (callback function)
  70 * @inode - inode struct of the target file
  71 * @blkoff - file block number
  72 * @bh_result - buffer head to be mapped on
  73 * @create - indicate whether allocating the block or not when it has not
  74 *      been allocated yet.
  75 *
  76 * This function does not issue actual read request of the specified data
  77 * block. It is done by VFS.
  78 */
  79int nilfs_get_block(struct inode *inode, sector_t blkoff,
  80		    struct buffer_head *bh_result, int create)
  81{
  82	struct nilfs_inode_info *ii = NILFS_I(inode);
  83	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
  84	__u64 blknum = 0;
  85	int err = 0, ret;
  86	unsigned int maxblocks = bh_result->b_size >> inode->i_blkbits;
  87
  88	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  89	ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  90	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  91	if (ret >= 0) {	/* found */
  92		map_bh(bh_result, inode->i_sb, blknum);
  93		if (ret > 0)
  94			bh_result->b_size = (ret << inode->i_blkbits);
  95		goto out;
  96	}
  97	/* data block was not found */
  98	if (ret == -ENOENT && create) {
  99		struct nilfs_transaction_info ti;
 100
 101		bh_result->b_blocknr = 0;
 102		err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
 103		if (unlikely(err))
 104			goto out;
 105		err = nilfs_bmap_insert(ii->i_bmap, blkoff,
 106					(unsigned long)bh_result);
 107		if (unlikely(err != 0)) {
 108			if (err == -EEXIST) {
 109				/*
 110				 * The get_block() function could be called
 111				 * from multiple callers for an inode.
 112				 * However, the page having this block must
 113				 * be locked in this case.
 114				 */
 115				nilfs_msg(inode->i_sb, KERN_WARNING,
 116					  "%s (ino=%lu): a race condition while inserting a data block at offset=%llu",
 117					  __func__, inode->i_ino,
 118					  (unsigned long long)blkoff);
 
 
 
 119				err = 0;
 120			}
 121			nilfs_transaction_abort(inode->i_sb);
 122			goto out;
 123		}
 124		nilfs_mark_inode_dirty_sync(inode);
 125		nilfs_transaction_commit(inode->i_sb); /* never fails */
 126		/* Error handling should be detailed */
 127		set_buffer_new(bh_result);
 128		set_buffer_delay(bh_result);
 129		map_bh(bh_result, inode->i_sb, 0);
 130		/* Disk block number must be changed to proper value */
 131
 132	} else if (ret == -ENOENT) {
 133		/*
 134		 * not found is not error (e.g. hole); must return without
 135		 * the mapped state flag.
 136		 */
 137		;
 138	} else {
 139		err = ret;
 140	}
 141
 142 out:
 143	return err;
 144}
 145
 146/**
 147 * nilfs_readpage() - implement readpage() method of nilfs_aops {}
 148 * address_space_operations.
 149 * @file - file struct of the file to be read
 150 * @page - the page to be read
 151 */
 152static int nilfs_readpage(struct file *file, struct page *page)
 153{
 154	return mpage_readpage(page, nilfs_get_block);
 155}
 156
 157/**
 158 * nilfs_readpages() - implement readpages() method of nilfs_aops {}
 159 * address_space_operations.
 160 * @file - file struct of the file to be read
 161 * @mapping - address_space struct used for reading multiple pages
 162 * @pages - the pages to be read
 163 * @nr_pages - number of pages to be read
 164 */
 165static int nilfs_readpages(struct file *file, struct address_space *mapping,
 166			   struct list_head *pages, unsigned int nr_pages)
 167{
 168	return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
 169}
 170
 171static int nilfs_writepages(struct address_space *mapping,
 172			    struct writeback_control *wbc)
 173{
 174	struct inode *inode = mapping->host;
 175	int err = 0;
 176
 177	if (sb_rdonly(inode->i_sb)) {
 178		nilfs_clear_dirty_pages(mapping, false);
 179		return -EROFS;
 180	}
 181
 182	if (wbc->sync_mode == WB_SYNC_ALL)
 183		err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 184						    wbc->range_start,
 185						    wbc->range_end);
 186	return err;
 187}
 188
 189static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 190{
 191	struct inode *inode = page->mapping->host;
 192	int err;
 193
 194	if (sb_rdonly(inode->i_sb)) {
 195		/*
 196		 * It means that filesystem was remounted in read-only
 197		 * mode because of error or metadata corruption. But we
 198		 * have dirty pages that try to be flushed in background.
 199		 * So, here we simply discard this dirty page.
 200		 */
 201		nilfs_clear_dirty_page(page, false);
 202		unlock_page(page);
 203		return -EROFS;
 204	}
 205
 206	redirty_page_for_writepage(wbc, page);
 207	unlock_page(page);
 208
 209	if (wbc->sync_mode == WB_SYNC_ALL) {
 210		err = nilfs_construct_segment(inode->i_sb);
 211		if (unlikely(err))
 212			return err;
 213	} else if (wbc->for_reclaim)
 214		nilfs_flush_segment(inode->i_sb, inode->i_ino);
 215
 216	return 0;
 217}
 218
 219static int nilfs_set_page_dirty(struct page *page)
 220{
 221	struct inode *inode = page->mapping->host;
 222	int ret = __set_page_dirty_nobuffers(page);
 223
 224	if (page_has_buffers(page)) {
 225		unsigned int nr_dirty = 0;
 226		struct buffer_head *bh, *head;
 227
 228		/*
 229		 * This page is locked by callers, and no other thread
 230		 * concurrently marks its buffers dirty since they are
 231		 * only dirtied through routines in fs/buffer.c in
 232		 * which call sites of mark_buffer_dirty are protected
 233		 * by page lock.
 234		 */
 235		bh = head = page_buffers(page);
 236		do {
 237			/* Do not mark hole blocks dirty */
 238			if (buffer_dirty(bh) || !buffer_mapped(bh))
 239				continue;
 240
 241			set_buffer_dirty(bh);
 242			nr_dirty++;
 243		} while (bh = bh->b_this_page, bh != head);
 244
 245		if (nr_dirty)
 246			nilfs_set_file_dirty(inode, nr_dirty);
 247	} else if (ret) {
 248		unsigned int nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 249
 250		nilfs_set_file_dirty(inode, nr_dirty);
 251	}
 252	return ret;
 253}
 254
 255void nilfs_write_failed(struct address_space *mapping, loff_t to)
 256{
 257	struct inode *inode = mapping->host;
 258
 259	if (to > inode->i_size) {
 260		truncate_pagecache(inode, inode->i_size);
 261		nilfs_truncate(inode);
 262	}
 263}
 264
 265static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 266			     loff_t pos, unsigned len, unsigned flags,
 267			     struct page **pagep, void **fsdata)
 268
 269{
 270	struct inode *inode = mapping->host;
 271	int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 272
 273	if (unlikely(err))
 274		return err;
 275
 276	err = block_write_begin(mapping, pos, len, flags, pagep,
 277				nilfs_get_block);
 278	if (unlikely(err)) {
 279		nilfs_write_failed(mapping, pos + len);
 280		nilfs_transaction_abort(inode->i_sb);
 281	}
 282	return err;
 283}
 284
 285static int nilfs_write_end(struct file *file, struct address_space *mapping,
 286			   loff_t pos, unsigned len, unsigned copied,
 287			   struct page *page, void *fsdata)
 288{
 289	struct inode *inode = mapping->host;
 290	unsigned int start = pos & (PAGE_SIZE - 1);
 291	unsigned int nr_dirty;
 292	int err;
 293
 294	nr_dirty = nilfs_page_count_clean_buffers(page, start,
 295						  start + copied);
 296	copied = generic_write_end(file, mapping, pos, len, copied, page,
 297				   fsdata);
 298	nilfs_set_file_dirty(inode, nr_dirty);
 299	err = nilfs_transaction_commit(inode->i_sb);
 300	return err ? : copied;
 301}
 302
 303static ssize_t
 304nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 305{
 306	struct inode *inode = file_inode(iocb->ki_filp);
 307
 308	if (iov_iter_rw(iter) == WRITE)
 309		return 0;
 310
 311	/* Needs synchronization with the cleaner */
 312	return blockdev_direct_IO(iocb, inode, iter, nilfs_get_block);
 313}
 314
 315const struct address_space_operations nilfs_aops = {
 316	.writepage		= nilfs_writepage,
 317	.readpage		= nilfs_readpage,
 318	.writepages		= nilfs_writepages,
 319	.set_page_dirty		= nilfs_set_page_dirty,
 320	.readpages		= nilfs_readpages,
 321	.write_begin		= nilfs_write_begin,
 322	.write_end		= nilfs_write_end,
 323	/* .releasepage		= nilfs_releasepage, */
 324	.invalidatepage		= block_invalidatepage,
 325	.direct_IO		= nilfs_direct_IO,
 326	.is_partially_uptodate  = block_is_partially_uptodate,
 327};
 328
 329static int nilfs_insert_inode_locked(struct inode *inode,
 330				     struct nilfs_root *root,
 331				     unsigned long ino)
 332{
 333	struct nilfs_iget_args args = {
 334		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 335	};
 336
 337	return insert_inode_locked4(inode, ino, nilfs_iget_test, &args);
 338}
 339
 340struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 341{
 342	struct super_block *sb = dir->i_sb;
 343	struct the_nilfs *nilfs = sb->s_fs_info;
 344	struct inode *inode;
 345	struct nilfs_inode_info *ii;
 346	struct nilfs_root *root;
 347	int err = -ENOMEM;
 348	ino_t ino;
 349
 350	inode = new_inode(sb);
 351	if (unlikely(!inode))
 352		goto failed;
 353
 354	mapping_set_gfp_mask(inode->i_mapping,
 355			   mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 356
 357	root = NILFS_I(dir)->i_root;
 358	ii = NILFS_I(inode);
 359	ii->i_state = BIT(NILFS_I_NEW);
 360	ii->i_root = root;
 361
 362	err = nilfs_ifile_create_inode(root->ifile, &ino, &ii->i_bh);
 363	if (unlikely(err))
 364		goto failed_ifile_create_inode;
 365	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
 366
 367	atomic64_inc(&root->inodes_count);
 368	inode_init_owner(inode, dir, mode);
 369	inode->i_ino = ino;
 370	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 371
 372	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
 373		err = nilfs_bmap_read(ii->i_bmap, NULL);
 374		if (err < 0)
 375			goto failed_after_creation;
 376
 377		set_bit(NILFS_I_BMAP, &ii->i_state);
 378		/* No lock is needed; iget() ensures it. */
 379	}
 380
 381	ii->i_flags = nilfs_mask_flags(
 382		mode, NILFS_I(dir)->i_flags & NILFS_FL_INHERITED);
 383
 384	/* ii->i_file_acl = 0; */
 385	/* ii->i_dir_acl = 0; */
 386	ii->i_dir_start_lookup = 0;
 387	nilfs_set_inode_flags(inode);
 388	spin_lock(&nilfs->ns_next_gen_lock);
 389	inode->i_generation = nilfs->ns_next_generation++;
 390	spin_unlock(&nilfs->ns_next_gen_lock);
 391	if (nilfs_insert_inode_locked(inode, root, ino) < 0) {
 392		err = -EIO;
 393		goto failed_after_creation;
 394	}
 395
 396	err = nilfs_init_acl(inode, dir);
 397	if (unlikely(err))
 398		/*
 399		 * Never occur.  When supporting nilfs_init_acl(),
 400		 * proper cancellation of above jobs should be considered.
 401		 */
 402		goto failed_after_creation;
 403
 404	return inode;
 405
 406 failed_after_creation:
 407	clear_nlink(inode);
 408	unlock_new_inode(inode);
 409	iput(inode);  /*
 410		       * raw_inode will be deleted through
 411		       * nilfs_evict_inode().
 412		       */
 413	goto failed;
 414
 415 failed_ifile_create_inode:
 416	make_bad_inode(inode);
 417	iput(inode);
 
 418 failed:
 419	return ERR_PTR(err);
 420}
 421
 422void nilfs_set_inode_flags(struct inode *inode)
 423{
 424	unsigned int flags = NILFS_I(inode)->i_flags;
 425	unsigned int new_fl = 0;
 426
 427	if (flags & FS_SYNC_FL)
 428		new_fl |= S_SYNC;
 429	if (flags & FS_APPEND_FL)
 430		new_fl |= S_APPEND;
 431	if (flags & FS_IMMUTABLE_FL)
 432		new_fl |= S_IMMUTABLE;
 433	if (flags & FS_NOATIME_FL)
 434		new_fl |= S_NOATIME;
 435	if (flags & FS_DIRSYNC_FL)
 436		new_fl |= S_DIRSYNC;
 437	inode_set_flags(inode, new_fl, S_SYNC | S_APPEND | S_IMMUTABLE |
 438			S_NOATIME | S_DIRSYNC);
 439}
 440
 441int nilfs_read_inode_common(struct inode *inode,
 442			    struct nilfs_inode *raw_inode)
 443{
 444	struct nilfs_inode_info *ii = NILFS_I(inode);
 445	int err;
 446
 447	inode->i_mode = le16_to_cpu(raw_inode->i_mode);
 448	i_uid_write(inode, le32_to_cpu(raw_inode->i_uid));
 449	i_gid_write(inode, le32_to_cpu(raw_inode->i_gid));
 450	set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
 451	inode->i_size = le64_to_cpu(raw_inode->i_size);
 452	inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 453	inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
 454	inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 455	inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 456	inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 457	inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 458	if (inode->i_nlink == 0)
 459		return -ESTALE; /* this inode is deleted */
 460
 461	inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 462	ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 463#if 0
 464	ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 465	ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 466		0 : le32_to_cpu(raw_inode->i_dir_acl);
 467#endif
 468	ii->i_dir_start_lookup = 0;
 469	inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 470
 471	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 472	    S_ISLNK(inode->i_mode)) {
 473		err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 474		if (err < 0)
 475			return err;
 476		set_bit(NILFS_I_BMAP, &ii->i_state);
 477		/* No lock is needed; iget() ensures it. */
 478	}
 479	return 0;
 480}
 481
 482static int __nilfs_read_inode(struct super_block *sb,
 483			      struct nilfs_root *root, unsigned long ino,
 484			      struct inode *inode)
 485{
 486	struct the_nilfs *nilfs = sb->s_fs_info;
 487	struct buffer_head *bh;
 488	struct nilfs_inode *raw_inode;
 489	int err;
 490
 491	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 492	err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
 493	if (unlikely(err))
 494		goto bad_inode;
 495
 496	raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
 497
 498	err = nilfs_read_inode_common(inode, raw_inode);
 499	if (err)
 500		goto failed_unmap;
 501
 502	if (S_ISREG(inode->i_mode)) {
 503		inode->i_op = &nilfs_file_inode_operations;
 504		inode->i_fop = &nilfs_file_operations;
 505		inode->i_mapping->a_ops = &nilfs_aops;
 506	} else if (S_ISDIR(inode->i_mode)) {
 507		inode->i_op = &nilfs_dir_inode_operations;
 508		inode->i_fop = &nilfs_dir_operations;
 509		inode->i_mapping->a_ops = &nilfs_aops;
 510	} else if (S_ISLNK(inode->i_mode)) {
 511		inode->i_op = &nilfs_symlink_inode_operations;
 512		inode_nohighmem(inode);
 513		inode->i_mapping->a_ops = &nilfs_aops;
 514	} else {
 515		inode->i_op = &nilfs_special_inode_operations;
 516		init_special_inode(
 517			inode, inode->i_mode,
 518			huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 519	}
 520	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 521	brelse(bh);
 522	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 523	nilfs_set_inode_flags(inode);
 524	mapping_set_gfp_mask(inode->i_mapping,
 525			   mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 526	return 0;
 527
 528 failed_unmap:
 529	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 530	brelse(bh);
 531
 532 bad_inode:
 533	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 534	return err;
 535}
 536
 537static int nilfs_iget_test(struct inode *inode, void *opaque)
 538{
 539	struct nilfs_iget_args *args = opaque;
 540	struct nilfs_inode_info *ii;
 541
 542	if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
 543		return 0;
 544
 545	ii = NILFS_I(inode);
 546	if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
 547		return !args->for_gc;
 548
 549	return args->for_gc && args->cno == ii->i_cno;
 550}
 551
 552static int nilfs_iget_set(struct inode *inode, void *opaque)
 553{
 554	struct nilfs_iget_args *args = opaque;
 555
 556	inode->i_ino = args->ino;
 557	if (args->for_gc) {
 558		NILFS_I(inode)->i_state = BIT(NILFS_I_GCINODE);
 559		NILFS_I(inode)->i_cno = args->cno;
 560		NILFS_I(inode)->i_root = NULL;
 561	} else {
 562		if (args->root && args->ino == NILFS_ROOT_INO)
 563			nilfs_get_root(args->root);
 564		NILFS_I(inode)->i_root = args->root;
 565	}
 566	return 0;
 567}
 568
 569struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
 570			    unsigned long ino)
 571{
 572	struct nilfs_iget_args args = {
 573		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 574	};
 575
 576	return ilookup5(sb, ino, nilfs_iget_test, &args);
 577}
 578
 579struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
 580				unsigned long ino)
 581{
 582	struct nilfs_iget_args args = {
 583		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 584	};
 585
 586	return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 587}
 588
 589struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
 590			 unsigned long ino)
 591{
 592	struct inode *inode;
 593	int err;
 594
 595	inode = nilfs_iget_locked(sb, root, ino);
 596	if (unlikely(!inode))
 597		return ERR_PTR(-ENOMEM);
 598	if (!(inode->i_state & I_NEW))
 599		return inode;
 600
 601	err = __nilfs_read_inode(sb, root, ino, inode);
 602	if (unlikely(err)) {
 603		iget_failed(inode);
 604		return ERR_PTR(err);
 605	}
 606	unlock_new_inode(inode);
 607	return inode;
 608}
 609
 610struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
 611				__u64 cno)
 612{
 613	struct nilfs_iget_args args = {
 614		.ino = ino, .root = NULL, .cno = cno, .for_gc = 1
 615	};
 616	struct inode *inode;
 617	int err;
 618
 619	inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 620	if (unlikely(!inode))
 621		return ERR_PTR(-ENOMEM);
 622	if (!(inode->i_state & I_NEW))
 623		return inode;
 624
 625	err = nilfs_init_gcinode(inode);
 626	if (unlikely(err)) {
 627		iget_failed(inode);
 628		return ERR_PTR(err);
 629	}
 630	unlock_new_inode(inode);
 631	return inode;
 632}
 633
 634void nilfs_write_inode_common(struct inode *inode,
 635			      struct nilfs_inode *raw_inode, int has_bmap)
 636{
 637	struct nilfs_inode_info *ii = NILFS_I(inode);
 638
 639	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 640	raw_inode->i_uid = cpu_to_le32(i_uid_read(inode));
 641	raw_inode->i_gid = cpu_to_le32(i_gid_read(inode));
 642	raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 643	raw_inode->i_size = cpu_to_le64(inode->i_size);
 644	raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 645	raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
 646	raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 647	raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 648	raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 649
 650	raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 651	raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 652
 653	if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) {
 654		struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 655
 656		/* zero-fill unused portion in the case of super root block */
 657		raw_inode->i_xattr = 0;
 658		raw_inode->i_pad = 0;
 659		memset((void *)raw_inode + sizeof(*raw_inode), 0,
 660		       nilfs->ns_inode_size - sizeof(*raw_inode));
 661	}
 662
 663	if (has_bmap)
 664		nilfs_bmap_write(ii->i_bmap, raw_inode);
 665	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 666		raw_inode->i_device_code =
 667			cpu_to_le64(huge_encode_dev(inode->i_rdev));
 668	/*
 669	 * When extending inode, nilfs->ns_inode_size should be checked
 670	 * for substitutions of appended fields.
 671	 */
 672}
 673
 674void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh, int flags)
 675{
 676	ino_t ino = inode->i_ino;
 677	struct nilfs_inode_info *ii = NILFS_I(inode);
 678	struct inode *ifile = ii->i_root->ifile;
 679	struct nilfs_inode *raw_inode;
 680
 681	raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
 682
 683	if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 684		memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
 685	if (flags & I_DIRTY_DATASYNC)
 686		set_bit(NILFS_I_INODE_SYNC, &ii->i_state);
 687
 688	nilfs_write_inode_common(inode, raw_inode, 0);
 689		/*
 690		 * XXX: call with has_bmap = 0 is a workaround to avoid
 691		 * deadlock of bmap.  This delays update of i_bmap to just
 692		 * before writing.
 693		 */
 694
 695	nilfs_ifile_unmap_inode(ifile, ino, ibh);
 696}
 697
 698#define NILFS_MAX_TRUNCATE_BLOCKS	16384  /* 64MB for 4KB block */
 699
 700static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 701				unsigned long from)
 702{
 703	__u64 b;
 704	int ret;
 705
 706	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 707		return;
 708repeat:
 709	ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 710	if (ret == -ENOENT)
 711		return;
 712	else if (ret < 0)
 713		goto failed;
 714
 715	if (b < from)
 716		return;
 717
 718	b -= min_t(__u64, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 719	ret = nilfs_bmap_truncate(ii->i_bmap, b);
 720	nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 721	if (!ret || (ret == -ENOMEM &&
 722		     nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 723		goto repeat;
 724
 725failed:
 726	nilfs_msg(ii->vfs_inode.i_sb, KERN_WARNING,
 727		  "error %d truncating bmap (ino=%lu)", ret,
 728		  ii->vfs_inode.i_ino);
 729}
 730
 731void nilfs_truncate(struct inode *inode)
 732{
 733	unsigned long blkoff;
 734	unsigned int blocksize;
 735	struct nilfs_transaction_info ti;
 736	struct super_block *sb = inode->i_sb;
 737	struct nilfs_inode_info *ii = NILFS_I(inode);
 738
 739	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 740		return;
 741	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 742		return;
 743
 744	blocksize = sb->s_blocksize;
 745	blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 746	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 747
 748	block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 749
 750	nilfs_truncate_bmap(ii, blkoff);
 751
 752	inode->i_mtime = inode->i_ctime = current_time(inode);
 753	if (IS_SYNC(inode))
 754		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 755
 756	nilfs_mark_inode_dirty(inode);
 757	nilfs_set_file_dirty(inode, 0);
 758	nilfs_transaction_commit(sb);
 759	/*
 760	 * May construct a logical segment and may fail in sync mode.
 761	 * But truncate has no return value.
 762	 */
 763}
 764
 765static void nilfs_clear_inode(struct inode *inode)
 766{
 767	struct nilfs_inode_info *ii = NILFS_I(inode);
 
 768
 769	/*
 770	 * Free resources allocated in nilfs_read_inode(), here.
 771	 */
 772	BUG_ON(!list_empty(&ii->i_dirty));
 773	brelse(ii->i_bh);
 774	ii->i_bh = NULL;
 775
 776	if (nilfs_is_metadata_file_inode(inode))
 777		nilfs_mdt_clear(inode);
 778
 779	if (test_bit(NILFS_I_BMAP, &ii->i_state))
 780		nilfs_bmap_clear(ii->i_bmap);
 781
 782	nilfs_btnode_cache_clear(&ii->i_btnode_cache);
 783
 784	if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
 785		nilfs_put_root(ii->i_root);
 786}
 787
 788void nilfs_evict_inode(struct inode *inode)
 789{
 790	struct nilfs_transaction_info ti;
 791	struct super_block *sb = inode->i_sb;
 792	struct nilfs_inode_info *ii = NILFS_I(inode);
 793	int ret;
 794
 795	if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
 796		truncate_inode_pages_final(&inode->i_data);
 797		clear_inode(inode);
 798		nilfs_clear_inode(inode);
 799		return;
 800	}
 801	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 802
 803	truncate_inode_pages_final(&inode->i_data);
 804
 805	/* TODO: some of the following operations may fail.  */
 806	nilfs_truncate_bmap(ii, 0);
 807	nilfs_mark_inode_dirty(inode);
 808	clear_inode(inode);
 809
 810	ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
 811	if (!ret)
 812		atomic64_dec(&ii->i_root->inodes_count);
 813
 814	nilfs_clear_inode(inode);
 815
 816	if (IS_SYNC(inode))
 817		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 818	nilfs_transaction_commit(sb);
 819	/*
 820	 * May construct a logical segment and may fail in sync mode.
 821	 * But delete_inode has no return value.
 822	 */
 823}
 824
 825int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 826{
 827	struct nilfs_transaction_info ti;
 828	struct inode *inode = d_inode(dentry);
 829	struct super_block *sb = inode->i_sb;
 830	int err;
 831
 832	err = setattr_prepare(dentry, iattr);
 833	if (err)
 834		return err;
 835
 836	err = nilfs_transaction_begin(sb, &ti, 0);
 837	if (unlikely(err))
 838		return err;
 839
 840	if ((iattr->ia_valid & ATTR_SIZE) &&
 841	    iattr->ia_size != i_size_read(inode)) {
 842		inode_dio_wait(inode);
 843		truncate_setsize(inode, iattr->ia_size);
 844		nilfs_truncate(inode);
 845	}
 846
 847	setattr_copy(inode, iattr);
 848	mark_inode_dirty(inode);
 849
 850	if (iattr->ia_valid & ATTR_MODE) {
 851		err = nilfs_acl_chmod(inode);
 852		if (unlikely(err))
 853			goto out_err;
 854	}
 855
 856	return nilfs_transaction_commit(sb);
 857
 858out_err:
 859	nilfs_transaction_abort(sb);
 860	return err;
 861}
 862
 863int nilfs_permission(struct inode *inode, int mask)
 864{
 865	struct nilfs_root *root = NILFS_I(inode)->i_root;
 866
 867	if ((mask & MAY_WRITE) && root &&
 868	    root->cno != NILFS_CPTREE_CURRENT_CNO)
 869		return -EROFS; /* snapshot is not writable */
 870
 871	return generic_permission(inode, mask);
 872}
 873
 874int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
 875{
 876	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 877	struct nilfs_inode_info *ii = NILFS_I(inode);
 878	int err;
 879
 880	spin_lock(&nilfs->ns_inode_lock);
 881	if (ii->i_bh == NULL) {
 882		spin_unlock(&nilfs->ns_inode_lock);
 883		err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
 884						  inode->i_ino, pbh);
 885		if (unlikely(err))
 886			return err;
 887		spin_lock(&nilfs->ns_inode_lock);
 888		if (ii->i_bh == NULL)
 889			ii->i_bh = *pbh;
 890		else {
 891			brelse(*pbh);
 892			*pbh = ii->i_bh;
 893		}
 894	} else
 895		*pbh = ii->i_bh;
 896
 897	get_bh(*pbh);
 898	spin_unlock(&nilfs->ns_inode_lock);
 899	return 0;
 900}
 901
 902int nilfs_inode_dirty(struct inode *inode)
 903{
 904	struct nilfs_inode_info *ii = NILFS_I(inode);
 905	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 906	int ret = 0;
 907
 908	if (!list_empty(&ii->i_dirty)) {
 909		spin_lock(&nilfs->ns_inode_lock);
 910		ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
 911			test_bit(NILFS_I_BUSY, &ii->i_state);
 912		spin_unlock(&nilfs->ns_inode_lock);
 913	}
 914	return ret;
 915}
 916
 917int nilfs_set_file_dirty(struct inode *inode, unsigned int nr_dirty)
 918{
 919	struct nilfs_inode_info *ii = NILFS_I(inode);
 920	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 921
 922	atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);
 923
 924	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
 925		return 0;
 926
 927	spin_lock(&nilfs->ns_inode_lock);
 928	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
 929	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
 930		/*
 931		 * Because this routine may race with nilfs_dispose_list(),
 932		 * we have to check NILFS_I_QUEUED here, too.
 933		 */
 934		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
 935			/*
 936			 * This will happen when somebody is freeing
 937			 * this inode.
 938			 */
 939			nilfs_msg(inode->i_sb, KERN_WARNING,
 940				  "cannot set file dirty (ino=%lu): the file is being freed",
 941				  inode->i_ino);
 942			spin_unlock(&nilfs->ns_inode_lock);
 943			return -EINVAL; /*
 944					 * NILFS_I_DIRTY may remain for
 945					 * freeing inode.
 946					 */
 947		}
 948		list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
 949		set_bit(NILFS_I_QUEUED, &ii->i_state);
 950	}
 951	spin_unlock(&nilfs->ns_inode_lock);
 952	return 0;
 953}
 954
 955int __nilfs_mark_inode_dirty(struct inode *inode, int flags)
 956{
 957	struct buffer_head *ibh;
 958	int err;
 959
 960	err = nilfs_load_inode_block(inode, &ibh);
 961	if (unlikely(err)) {
 962		nilfs_msg(inode->i_sb, KERN_WARNING,
 963			  "cannot mark inode dirty (ino=%lu): error %d loading inode block",
 964			  inode->i_ino, err);
 965		return err;
 966	}
 967	nilfs_update_inode(inode, ibh, flags);
 968	mark_buffer_dirty(ibh);
 969	nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
 970	brelse(ibh);
 971	return 0;
 972}
 973
 974/**
 975 * nilfs_dirty_inode - reflect changes on given inode to an inode block.
 976 * @inode: inode of the file to be registered.
 977 *
 978 * nilfs_dirty_inode() loads a inode block containing the specified
 979 * @inode and copies data from a nilfs_inode to a corresponding inode
 980 * entry in the inode block. This operation is excluded from the segment
 981 * construction. This function can be called both as a single operation
 982 * and as a part of indivisible file operations.
 983 */
 984void nilfs_dirty_inode(struct inode *inode, int flags)
 985{
 986	struct nilfs_transaction_info ti;
 987	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 988
 989	if (is_bad_inode(inode)) {
 990		nilfs_msg(inode->i_sb, KERN_WARNING,
 991			  "tried to mark bad_inode dirty. ignored.");
 992		dump_stack();
 993		return;
 994	}
 995	if (mdi) {
 996		nilfs_mdt_mark_dirty(inode);
 997		return;
 998	}
 999	nilfs_transaction_begin(inode->i_sb, &ti, 0);
1000	__nilfs_mark_inode_dirty(inode, flags);
1001	nilfs_transaction_commit(inode->i_sb); /* never fails */
1002}
1003
1004int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1005		 __u64 start, __u64 len)
1006{
1007	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1008	__u64 logical = 0, phys = 0, size = 0;
1009	__u32 flags = 0;
1010	loff_t isize;
1011	sector_t blkoff, end_blkoff;
1012	sector_t delalloc_blkoff;
1013	unsigned long delalloc_blklen;
1014	unsigned int blkbits = inode->i_blkbits;
1015	int ret, n;
1016
1017	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1018	if (ret)
1019		return ret;
1020
1021	inode_lock(inode);
1022
1023	isize = i_size_read(inode);
1024
1025	blkoff = start >> blkbits;
1026	end_blkoff = (start + len - 1) >> blkbits;
1027
1028	delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
1029							&delalloc_blkoff);
1030
1031	do {
1032		__u64 blkphy;
1033		unsigned int maxblocks;
1034
1035		if (delalloc_blklen && blkoff == delalloc_blkoff) {
1036			if (size) {
1037				/* End of the current extent */
1038				ret = fiemap_fill_next_extent(
1039					fieinfo, logical, phys, size, flags);
1040				if (ret)
1041					break;
1042			}
1043			if (blkoff > end_blkoff)
1044				break;
1045
1046			flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
1047			logical = blkoff << blkbits;
1048			phys = 0;
1049			size = delalloc_blklen << blkbits;
1050
1051			blkoff = delalloc_blkoff + delalloc_blklen;
1052			delalloc_blklen = nilfs_find_uncommitted_extent(
1053				inode, blkoff, &delalloc_blkoff);
1054			continue;
1055		}
1056
1057		/*
1058		 * Limit the number of blocks that we look up so as
1059		 * not to get into the next delayed allocation extent.
1060		 */
1061		maxblocks = INT_MAX;
1062		if (delalloc_blklen)
1063			maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
1064					  maxblocks);
1065		blkphy = 0;
1066
1067		down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1068		n = nilfs_bmap_lookup_contig(
1069			NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
1070		up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1071
1072		if (n < 0) {
1073			int past_eof;
1074
1075			if (unlikely(n != -ENOENT))
1076				break; /* error */
1077
1078			/* HOLE */
1079			blkoff++;
1080			past_eof = ((blkoff << blkbits) >= isize);
1081
1082			if (size) {
1083				/* End of the current extent */
1084
1085				if (past_eof)
1086					flags |= FIEMAP_EXTENT_LAST;
1087
1088				ret = fiemap_fill_next_extent(
1089					fieinfo, logical, phys, size, flags);
1090				if (ret)
1091					break;
1092				size = 0;
1093			}
1094			if (blkoff > end_blkoff || past_eof)
1095				break;
1096		} else {
1097			if (size) {
1098				if (phys && blkphy << blkbits == phys + size) {
1099					/* The current extent goes on */
1100					size += n << blkbits;
1101				} else {
1102					/* Terminate the current extent */
1103					ret = fiemap_fill_next_extent(
1104						fieinfo, logical, phys, size,
1105						flags);
1106					if (ret || blkoff > end_blkoff)
1107						break;
1108
1109					/* Start another extent */
1110					flags = FIEMAP_EXTENT_MERGED;
1111					logical = blkoff << blkbits;
1112					phys = blkphy << blkbits;
1113					size = n << blkbits;
1114				}
1115			} else {
1116				/* Start a new extent */
1117				flags = FIEMAP_EXTENT_MERGED;
1118				logical = blkoff << blkbits;
1119				phys = blkphy << blkbits;
1120				size = n << blkbits;
1121			}
1122			blkoff += n;
1123		}
1124		cond_resched();
1125	} while (true);
1126
1127	/* If ret is 1 then we just hit the end of the extent array */
1128	if (ret == 1)
1129		ret = 0;
1130
1131	inode_unlock(inode);
1132	return ret;
1133}
v4.6
   1/*
   2 * inode.c - NILFS inode operations.
   3 *
   4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19 *
  20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
  21 *
  22 */
  23
  24#include <linux/buffer_head.h>
  25#include <linux/gfp.h>
  26#include <linux/mpage.h>
  27#include <linux/pagemap.h>
  28#include <linux/writeback.h>
  29#include <linux/uio.h>
  30#include "nilfs.h"
  31#include "btnode.h"
  32#include "segment.h"
  33#include "page.h"
  34#include "mdt.h"
  35#include "cpfile.h"
  36#include "ifile.h"
  37
  38/**
  39 * struct nilfs_iget_args - arguments used during comparison between inodes
  40 * @ino: inode number
  41 * @cno: checkpoint number
  42 * @root: pointer on NILFS root object (mounted checkpoint)
  43 * @for_gc: inode for GC flag
  44 */
  45struct nilfs_iget_args {
  46	u64 ino;
  47	__u64 cno;
  48	struct nilfs_root *root;
  49	int for_gc;
  50};
  51
  52static int nilfs_iget_test(struct inode *inode, void *opaque);
  53
  54void nilfs_inode_add_blocks(struct inode *inode, int n)
  55{
  56	struct nilfs_root *root = NILFS_I(inode)->i_root;
  57
  58	inode_add_bytes(inode, (1 << inode->i_blkbits) * n);
  59	if (root)
  60		atomic64_add(n, &root->blocks_count);
  61}
  62
  63void nilfs_inode_sub_blocks(struct inode *inode, int n)
  64{
  65	struct nilfs_root *root = NILFS_I(inode)->i_root;
  66
  67	inode_sub_bytes(inode, (1 << inode->i_blkbits) * n);
  68	if (root)
  69		atomic64_sub(n, &root->blocks_count);
  70}
  71
  72/**
  73 * nilfs_get_block() - get a file block on the filesystem (callback function)
  74 * @inode - inode struct of the target file
  75 * @blkoff - file block number
  76 * @bh_result - buffer head to be mapped on
  77 * @create - indicate whether allocating the block or not when it has not
  78 *      been allocated yet.
  79 *
  80 * This function does not issue actual read request of the specified data
  81 * block. It is done by VFS.
  82 */
  83int nilfs_get_block(struct inode *inode, sector_t blkoff,
  84		    struct buffer_head *bh_result, int create)
  85{
  86	struct nilfs_inode_info *ii = NILFS_I(inode);
  87	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
  88	__u64 blknum = 0;
  89	int err = 0, ret;
  90	unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;
  91
  92	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  93	ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  94	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  95	if (ret >= 0) {	/* found */
  96		map_bh(bh_result, inode->i_sb, blknum);
  97		if (ret > 0)
  98			bh_result->b_size = (ret << inode->i_blkbits);
  99		goto out;
 100	}
 101	/* data block was not found */
 102	if (ret == -ENOENT && create) {
 103		struct nilfs_transaction_info ti;
 104
 105		bh_result->b_blocknr = 0;
 106		err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
 107		if (unlikely(err))
 108			goto out;
 109		err = nilfs_bmap_insert(ii->i_bmap, blkoff,
 110					(unsigned long)bh_result);
 111		if (unlikely(err != 0)) {
 112			if (err == -EEXIST) {
 113				/*
 114				 * The get_block() function could be called
 115				 * from multiple callers for an inode.
 116				 * However, the page having this block must
 117				 * be locked in this case.
 118				 */
 119				printk(KERN_WARNING
 120				       "nilfs_get_block: a race condition "
 121				       "while inserting a data block. "
 122				       "(inode number=%lu, file block "
 123				       "offset=%llu)\n",
 124				       inode->i_ino,
 125				       (unsigned long long)blkoff);
 126				err = 0;
 127			}
 128			nilfs_transaction_abort(inode->i_sb);
 129			goto out;
 130		}
 131		nilfs_mark_inode_dirty_sync(inode);
 132		nilfs_transaction_commit(inode->i_sb); /* never fails */
 133		/* Error handling should be detailed */
 134		set_buffer_new(bh_result);
 135		set_buffer_delay(bh_result);
 136		map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
 137						      to proper value */
 
 138	} else if (ret == -ENOENT) {
 139		/* not found is not error (e.g. hole); must return without
 140		   the mapped state flag. */
 
 
 141		;
 142	} else {
 143		err = ret;
 144	}
 145
 146 out:
 147	return err;
 148}
 149
 150/**
 151 * nilfs_readpage() - implement readpage() method of nilfs_aops {}
 152 * address_space_operations.
 153 * @file - file struct of the file to be read
 154 * @page - the page to be read
 155 */
 156static int nilfs_readpage(struct file *file, struct page *page)
 157{
 158	return mpage_readpage(page, nilfs_get_block);
 159}
 160
 161/**
 162 * nilfs_readpages() - implement readpages() method of nilfs_aops {}
 163 * address_space_operations.
 164 * @file - file struct of the file to be read
 165 * @mapping - address_space struct used for reading multiple pages
 166 * @pages - the pages to be read
 167 * @nr_pages - number of pages to be read
 168 */
 169static int nilfs_readpages(struct file *file, struct address_space *mapping,
 170			   struct list_head *pages, unsigned nr_pages)
 171{
 172	return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
 173}
 174
 175static int nilfs_writepages(struct address_space *mapping,
 176			    struct writeback_control *wbc)
 177{
 178	struct inode *inode = mapping->host;
 179	int err = 0;
 180
 181	if (inode->i_sb->s_flags & MS_RDONLY) {
 182		nilfs_clear_dirty_pages(mapping, false);
 183		return -EROFS;
 184	}
 185
 186	if (wbc->sync_mode == WB_SYNC_ALL)
 187		err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 188						    wbc->range_start,
 189						    wbc->range_end);
 190	return err;
 191}
 192
 193static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 194{
 195	struct inode *inode = page->mapping->host;
 196	int err;
 197
 198	if (inode->i_sb->s_flags & MS_RDONLY) {
 199		/*
 200		 * It means that filesystem was remounted in read-only
 201		 * mode because of error or metadata corruption. But we
 202		 * have dirty pages that try to be flushed in background.
 203		 * So, here we simply discard this dirty page.
 204		 */
 205		nilfs_clear_dirty_page(page, false);
 206		unlock_page(page);
 207		return -EROFS;
 208	}
 209
 210	redirty_page_for_writepage(wbc, page);
 211	unlock_page(page);
 212
 213	if (wbc->sync_mode == WB_SYNC_ALL) {
 214		err = nilfs_construct_segment(inode->i_sb);
 215		if (unlikely(err))
 216			return err;
 217	} else if (wbc->for_reclaim)
 218		nilfs_flush_segment(inode->i_sb, inode->i_ino);
 219
 220	return 0;
 221}
 222
 223static int nilfs_set_page_dirty(struct page *page)
 224{
 225	struct inode *inode = page->mapping->host;
 226	int ret = __set_page_dirty_nobuffers(page);
 227
 228	if (page_has_buffers(page)) {
 229		unsigned nr_dirty = 0;
 230		struct buffer_head *bh, *head;
 231
 232		/*
 233		 * This page is locked by callers, and no other thread
 234		 * concurrently marks its buffers dirty since they are
 235		 * only dirtied through routines in fs/buffer.c in
 236		 * which call sites of mark_buffer_dirty are protected
 237		 * by page lock.
 238		 */
 239		bh = head = page_buffers(page);
 240		do {
 241			/* Do not mark hole blocks dirty */
 242			if (buffer_dirty(bh) || !buffer_mapped(bh))
 243				continue;
 244
 245			set_buffer_dirty(bh);
 246			nr_dirty++;
 247		} while (bh = bh->b_this_page, bh != head);
 248
 249		if (nr_dirty)
 250			nilfs_set_file_dirty(inode, nr_dirty);
 251	} else if (ret) {
 252		unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 253
 254		nilfs_set_file_dirty(inode, nr_dirty);
 255	}
 256	return ret;
 257}
 258
 259void nilfs_write_failed(struct address_space *mapping, loff_t to)
 260{
 261	struct inode *inode = mapping->host;
 262
 263	if (to > inode->i_size) {
 264		truncate_pagecache(inode, inode->i_size);
 265		nilfs_truncate(inode);
 266	}
 267}
 268
 269static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 270			     loff_t pos, unsigned len, unsigned flags,
 271			     struct page **pagep, void **fsdata)
 272
 273{
 274	struct inode *inode = mapping->host;
 275	int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 276
 277	if (unlikely(err))
 278		return err;
 279
 280	err = block_write_begin(mapping, pos, len, flags, pagep,
 281				nilfs_get_block);
 282	if (unlikely(err)) {
 283		nilfs_write_failed(mapping, pos + len);
 284		nilfs_transaction_abort(inode->i_sb);
 285	}
 286	return err;
 287}
 288
 289static int nilfs_write_end(struct file *file, struct address_space *mapping,
 290			   loff_t pos, unsigned len, unsigned copied,
 291			   struct page *page, void *fsdata)
 292{
 293	struct inode *inode = mapping->host;
 294	unsigned start = pos & (PAGE_SIZE - 1);
 295	unsigned nr_dirty;
 296	int err;
 297
 298	nr_dirty = nilfs_page_count_clean_buffers(page, start,
 299						  start + copied);
 300	copied = generic_write_end(file, mapping, pos, len, copied, page,
 301				   fsdata);
 302	nilfs_set_file_dirty(inode, nr_dirty);
 303	err = nilfs_transaction_commit(inode->i_sb);
 304	return err ? : copied;
 305}
 306
 307static ssize_t
 308nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset)
 309{
 310	struct inode *inode = file_inode(iocb->ki_filp);
 311
 312	if (iov_iter_rw(iter) == WRITE)
 313		return 0;
 314
 315	/* Needs synchronization with the cleaner */
 316	return blockdev_direct_IO(iocb, inode, iter, offset, nilfs_get_block);
 317}
 318
 319const struct address_space_operations nilfs_aops = {
 320	.writepage		= nilfs_writepage,
 321	.readpage		= nilfs_readpage,
 322	.writepages		= nilfs_writepages,
 323	.set_page_dirty		= nilfs_set_page_dirty,
 324	.readpages		= nilfs_readpages,
 325	.write_begin		= nilfs_write_begin,
 326	.write_end		= nilfs_write_end,
 327	/* .releasepage		= nilfs_releasepage, */
 328	.invalidatepage		= block_invalidatepage,
 329	.direct_IO		= nilfs_direct_IO,
 330	.is_partially_uptodate  = block_is_partially_uptodate,
 331};
 332
 333static int nilfs_insert_inode_locked(struct inode *inode,
 334				     struct nilfs_root *root,
 335				     unsigned long ino)
 336{
 337	struct nilfs_iget_args args = {
 338		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 339	};
 340
 341	return insert_inode_locked4(inode, ino, nilfs_iget_test, &args);
 342}
 343
 344struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 345{
 346	struct super_block *sb = dir->i_sb;
 347	struct the_nilfs *nilfs = sb->s_fs_info;
 348	struct inode *inode;
 349	struct nilfs_inode_info *ii;
 350	struct nilfs_root *root;
 351	int err = -ENOMEM;
 352	ino_t ino;
 353
 354	inode = new_inode(sb);
 355	if (unlikely(!inode))
 356		goto failed;
 357
 358	mapping_set_gfp_mask(inode->i_mapping,
 359			   mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 360
 361	root = NILFS_I(dir)->i_root;
 362	ii = NILFS_I(inode);
 363	ii->i_state = 1 << NILFS_I_NEW;
 364	ii->i_root = root;
 365
 366	err = nilfs_ifile_create_inode(root->ifile, &ino, &ii->i_bh);
 367	if (unlikely(err))
 368		goto failed_ifile_create_inode;
 369	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
 370
 371	atomic64_inc(&root->inodes_count);
 372	inode_init_owner(inode, dir, mode);
 373	inode->i_ino = ino;
 374	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 375
 376	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
 377		err = nilfs_bmap_read(ii->i_bmap, NULL);
 378		if (err < 0)
 379			goto failed_after_creation;
 380
 381		set_bit(NILFS_I_BMAP, &ii->i_state);
 382		/* No lock is needed; iget() ensures it. */
 383	}
 384
 385	ii->i_flags = nilfs_mask_flags(
 386		mode, NILFS_I(dir)->i_flags & NILFS_FL_INHERITED);
 387
 388	/* ii->i_file_acl = 0; */
 389	/* ii->i_dir_acl = 0; */
 390	ii->i_dir_start_lookup = 0;
 391	nilfs_set_inode_flags(inode);
 392	spin_lock(&nilfs->ns_next_gen_lock);
 393	inode->i_generation = nilfs->ns_next_generation++;
 394	spin_unlock(&nilfs->ns_next_gen_lock);
 395	if (nilfs_insert_inode_locked(inode, root, ino) < 0) {
 396		err = -EIO;
 397		goto failed_after_creation;
 398	}
 399
 400	err = nilfs_init_acl(inode, dir);
 401	if (unlikely(err))
 402		goto failed_after_creation; /* never occur. When supporting
 403				    nilfs_init_acl(), proper cancellation of
 404				    above jobs should be considered */
 
 
 405
 406	return inode;
 407
 408 failed_after_creation:
 409	clear_nlink(inode);
 410	unlock_new_inode(inode);
 411	iput(inode);  /* raw_inode will be deleted through
 412			 nilfs_evict_inode() */
 
 
 413	goto failed;
 414
 415 failed_ifile_create_inode:
 416	make_bad_inode(inode);
 417	iput(inode);  /* if i_nlink == 1, generic_forget_inode() will be
 418			 called */
 419 failed:
 420	return ERR_PTR(err);
 421}
 422
 423void nilfs_set_inode_flags(struct inode *inode)
 424{
 425	unsigned int flags = NILFS_I(inode)->i_flags;
 426	unsigned int new_fl = 0;
 427
 428	if (flags & FS_SYNC_FL)
 429		new_fl |= S_SYNC;
 430	if (flags & FS_APPEND_FL)
 431		new_fl |= S_APPEND;
 432	if (flags & FS_IMMUTABLE_FL)
 433		new_fl |= S_IMMUTABLE;
 434	if (flags & FS_NOATIME_FL)
 435		new_fl |= S_NOATIME;
 436	if (flags & FS_DIRSYNC_FL)
 437		new_fl |= S_DIRSYNC;
 438	inode_set_flags(inode, new_fl, S_SYNC | S_APPEND | S_IMMUTABLE |
 439			S_NOATIME | S_DIRSYNC);
 440}
 441
 442int nilfs_read_inode_common(struct inode *inode,
 443			    struct nilfs_inode *raw_inode)
 444{
 445	struct nilfs_inode_info *ii = NILFS_I(inode);
 446	int err;
 447
 448	inode->i_mode = le16_to_cpu(raw_inode->i_mode);
 449	i_uid_write(inode, le32_to_cpu(raw_inode->i_uid));
 450	i_gid_write(inode, le32_to_cpu(raw_inode->i_gid));
 451	set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
 452	inode->i_size = le64_to_cpu(raw_inode->i_size);
 453	inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 454	inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
 455	inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 456	inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 457	inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 458	inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 459	if (inode->i_nlink == 0)
 460		return -ESTALE; /* this inode is deleted */
 461
 462	inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 463	ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 464#if 0
 465	ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 466	ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 467		0 : le32_to_cpu(raw_inode->i_dir_acl);
 468#endif
 469	ii->i_dir_start_lookup = 0;
 470	inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 471
 472	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 473	    S_ISLNK(inode->i_mode)) {
 474		err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 475		if (err < 0)
 476			return err;
 477		set_bit(NILFS_I_BMAP, &ii->i_state);
 478		/* No lock is needed; iget() ensures it. */
 479	}
 480	return 0;
 481}
 482
 483static int __nilfs_read_inode(struct super_block *sb,
 484			      struct nilfs_root *root, unsigned long ino,
 485			      struct inode *inode)
 486{
 487	struct the_nilfs *nilfs = sb->s_fs_info;
 488	struct buffer_head *bh;
 489	struct nilfs_inode *raw_inode;
 490	int err;
 491
 492	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 493	err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
 494	if (unlikely(err))
 495		goto bad_inode;
 496
 497	raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
 498
 499	err = nilfs_read_inode_common(inode, raw_inode);
 500	if (err)
 501		goto failed_unmap;
 502
 503	if (S_ISREG(inode->i_mode)) {
 504		inode->i_op = &nilfs_file_inode_operations;
 505		inode->i_fop = &nilfs_file_operations;
 506		inode->i_mapping->a_ops = &nilfs_aops;
 507	} else if (S_ISDIR(inode->i_mode)) {
 508		inode->i_op = &nilfs_dir_inode_operations;
 509		inode->i_fop = &nilfs_dir_operations;
 510		inode->i_mapping->a_ops = &nilfs_aops;
 511	} else if (S_ISLNK(inode->i_mode)) {
 512		inode->i_op = &nilfs_symlink_inode_operations;
 513		inode_nohighmem(inode);
 514		inode->i_mapping->a_ops = &nilfs_aops;
 515	} else {
 516		inode->i_op = &nilfs_special_inode_operations;
 517		init_special_inode(
 518			inode, inode->i_mode,
 519			huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 520	}
 521	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 522	brelse(bh);
 523	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 524	nilfs_set_inode_flags(inode);
 525	mapping_set_gfp_mask(inode->i_mapping,
 526			   mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 527	return 0;
 528
 529 failed_unmap:
 530	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 531	brelse(bh);
 532
 533 bad_inode:
 534	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 535	return err;
 536}
 537
 538static int nilfs_iget_test(struct inode *inode, void *opaque)
 539{
 540	struct nilfs_iget_args *args = opaque;
 541	struct nilfs_inode_info *ii;
 542
 543	if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
 544		return 0;
 545
 546	ii = NILFS_I(inode);
 547	if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
 548		return !args->for_gc;
 549
 550	return args->for_gc && args->cno == ii->i_cno;
 551}
 552
 553static int nilfs_iget_set(struct inode *inode, void *opaque)
 554{
 555	struct nilfs_iget_args *args = opaque;
 556
 557	inode->i_ino = args->ino;
 558	if (args->for_gc) {
 559		NILFS_I(inode)->i_state = 1 << NILFS_I_GCINODE;
 560		NILFS_I(inode)->i_cno = args->cno;
 561		NILFS_I(inode)->i_root = NULL;
 562	} else {
 563		if (args->root && args->ino == NILFS_ROOT_INO)
 564			nilfs_get_root(args->root);
 565		NILFS_I(inode)->i_root = args->root;
 566	}
 567	return 0;
 568}
 569
 570struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
 571			    unsigned long ino)
 572{
 573	struct nilfs_iget_args args = {
 574		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 575	};
 576
 577	return ilookup5(sb, ino, nilfs_iget_test, &args);
 578}
 579
 580struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
 581				unsigned long ino)
 582{
 583	struct nilfs_iget_args args = {
 584		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 585	};
 586
 587	return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 588}
 589
 590struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
 591			 unsigned long ino)
 592{
 593	struct inode *inode;
 594	int err;
 595
 596	inode = nilfs_iget_locked(sb, root, ino);
 597	if (unlikely(!inode))
 598		return ERR_PTR(-ENOMEM);
 599	if (!(inode->i_state & I_NEW))
 600		return inode;
 601
 602	err = __nilfs_read_inode(sb, root, ino, inode);
 603	if (unlikely(err)) {
 604		iget_failed(inode);
 605		return ERR_PTR(err);
 606	}
 607	unlock_new_inode(inode);
 608	return inode;
 609}
 610
 611struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
 612				__u64 cno)
 613{
 614	struct nilfs_iget_args args = {
 615		.ino = ino, .root = NULL, .cno = cno, .for_gc = 1
 616	};
 617	struct inode *inode;
 618	int err;
 619
 620	inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 621	if (unlikely(!inode))
 622		return ERR_PTR(-ENOMEM);
 623	if (!(inode->i_state & I_NEW))
 624		return inode;
 625
 626	err = nilfs_init_gcinode(inode);
 627	if (unlikely(err)) {
 628		iget_failed(inode);
 629		return ERR_PTR(err);
 630	}
 631	unlock_new_inode(inode);
 632	return inode;
 633}
 634
 635void nilfs_write_inode_common(struct inode *inode,
 636			      struct nilfs_inode *raw_inode, int has_bmap)
 637{
 638	struct nilfs_inode_info *ii = NILFS_I(inode);
 639
 640	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 641	raw_inode->i_uid = cpu_to_le32(i_uid_read(inode));
 642	raw_inode->i_gid = cpu_to_le32(i_gid_read(inode));
 643	raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 644	raw_inode->i_size = cpu_to_le64(inode->i_size);
 645	raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 646	raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
 647	raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 648	raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 649	raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 650
 651	raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 652	raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 653
 654	if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) {
 655		struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 656
 657		/* zero-fill unused portion in the case of super root block */
 658		raw_inode->i_xattr = 0;
 659		raw_inode->i_pad = 0;
 660		memset((void *)raw_inode + sizeof(*raw_inode), 0,
 661		       nilfs->ns_inode_size - sizeof(*raw_inode));
 662	}
 663
 664	if (has_bmap)
 665		nilfs_bmap_write(ii->i_bmap, raw_inode);
 666	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 667		raw_inode->i_device_code =
 668			cpu_to_le64(huge_encode_dev(inode->i_rdev));
 669	/* When extending inode, nilfs->ns_inode_size should be checked
 670	   for substitutions of appended fields */
 
 
 671}
 672
 673void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh, int flags)
 674{
 675	ino_t ino = inode->i_ino;
 676	struct nilfs_inode_info *ii = NILFS_I(inode);
 677	struct inode *ifile = ii->i_root->ifile;
 678	struct nilfs_inode *raw_inode;
 679
 680	raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
 681
 682	if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 683		memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
 684	if (flags & I_DIRTY_DATASYNC)
 685		set_bit(NILFS_I_INODE_SYNC, &ii->i_state);
 686
 687	nilfs_write_inode_common(inode, raw_inode, 0);
 688		/* XXX: call with has_bmap = 0 is a workaround to avoid
 689		   deadlock of bmap. This delays update of i_bmap to just
 690		   before writing */
 
 
 
 691	nilfs_ifile_unmap_inode(ifile, ino, ibh);
 692}
 693
 694#define NILFS_MAX_TRUNCATE_BLOCKS	16384  /* 64MB for 4KB block */
 695
 696static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 697				unsigned long from)
 698{
 699	__u64 b;
 700	int ret;
 701
 702	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 703		return;
 704repeat:
 705	ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 706	if (ret == -ENOENT)
 707		return;
 708	else if (ret < 0)
 709		goto failed;
 710
 711	if (b < from)
 712		return;
 713
 714	b -= min_t(__u64, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 715	ret = nilfs_bmap_truncate(ii->i_bmap, b);
 716	nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 717	if (!ret || (ret == -ENOMEM &&
 718		     nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 719		goto repeat;
 720
 721failed:
 722	nilfs_warning(ii->vfs_inode.i_sb, __func__,
 723		      "failed to truncate bmap (ino=%lu, err=%d)",
 724		      ii->vfs_inode.i_ino, ret);
 725}
 726
 727void nilfs_truncate(struct inode *inode)
 728{
 729	unsigned long blkoff;
 730	unsigned int blocksize;
 731	struct nilfs_transaction_info ti;
 732	struct super_block *sb = inode->i_sb;
 733	struct nilfs_inode_info *ii = NILFS_I(inode);
 734
 735	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 736		return;
 737	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 738		return;
 739
 740	blocksize = sb->s_blocksize;
 741	blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 742	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 743
 744	block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 745
 746	nilfs_truncate_bmap(ii, blkoff);
 747
 748	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 749	if (IS_SYNC(inode))
 750		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 751
 752	nilfs_mark_inode_dirty(inode);
 753	nilfs_set_file_dirty(inode, 0);
 754	nilfs_transaction_commit(sb);
 755	/* May construct a logical segment and may fail in sync mode.
 756	   But truncate has no return value. */
 
 
 757}
 758
 759static void nilfs_clear_inode(struct inode *inode)
 760{
 761	struct nilfs_inode_info *ii = NILFS_I(inode);
 762	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 763
 764	/*
 765	 * Free resources allocated in nilfs_read_inode(), here.
 766	 */
 767	BUG_ON(!list_empty(&ii->i_dirty));
 768	brelse(ii->i_bh);
 769	ii->i_bh = NULL;
 770
 771	if (mdi && mdi->mi_palloc_cache)
 772		nilfs_palloc_destroy_cache(inode);
 773
 774	if (test_bit(NILFS_I_BMAP, &ii->i_state))
 775		nilfs_bmap_clear(ii->i_bmap);
 776
 777	nilfs_btnode_cache_clear(&ii->i_btnode_cache);
 778
 779	if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
 780		nilfs_put_root(ii->i_root);
 781}
 782
 783void nilfs_evict_inode(struct inode *inode)
 784{
 785	struct nilfs_transaction_info ti;
 786	struct super_block *sb = inode->i_sb;
 787	struct nilfs_inode_info *ii = NILFS_I(inode);
 788	int ret;
 789
 790	if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
 791		truncate_inode_pages_final(&inode->i_data);
 792		clear_inode(inode);
 793		nilfs_clear_inode(inode);
 794		return;
 795	}
 796	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 797
 798	truncate_inode_pages_final(&inode->i_data);
 799
 800	/* TODO: some of the following operations may fail.  */
 801	nilfs_truncate_bmap(ii, 0);
 802	nilfs_mark_inode_dirty(inode);
 803	clear_inode(inode);
 804
 805	ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
 806	if (!ret)
 807		atomic64_dec(&ii->i_root->inodes_count);
 808
 809	nilfs_clear_inode(inode);
 810
 811	if (IS_SYNC(inode))
 812		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 813	nilfs_transaction_commit(sb);
 814	/* May construct a logical segment and may fail in sync mode.
 815	   But delete_inode has no return value. */
 
 
 816}
 817
 818int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 819{
 820	struct nilfs_transaction_info ti;
 821	struct inode *inode = d_inode(dentry);
 822	struct super_block *sb = inode->i_sb;
 823	int err;
 824
 825	err = inode_change_ok(inode, iattr);
 826	if (err)
 827		return err;
 828
 829	err = nilfs_transaction_begin(sb, &ti, 0);
 830	if (unlikely(err))
 831		return err;
 832
 833	if ((iattr->ia_valid & ATTR_SIZE) &&
 834	    iattr->ia_size != i_size_read(inode)) {
 835		inode_dio_wait(inode);
 836		truncate_setsize(inode, iattr->ia_size);
 837		nilfs_truncate(inode);
 838	}
 839
 840	setattr_copy(inode, iattr);
 841	mark_inode_dirty(inode);
 842
 843	if (iattr->ia_valid & ATTR_MODE) {
 844		err = nilfs_acl_chmod(inode);
 845		if (unlikely(err))
 846			goto out_err;
 847	}
 848
 849	return nilfs_transaction_commit(sb);
 850
 851out_err:
 852	nilfs_transaction_abort(sb);
 853	return err;
 854}
 855
 856int nilfs_permission(struct inode *inode, int mask)
 857{
 858	struct nilfs_root *root = NILFS_I(inode)->i_root;
 
 859	if ((mask & MAY_WRITE) && root &&
 860	    root->cno != NILFS_CPTREE_CURRENT_CNO)
 861		return -EROFS; /* snapshot is not writable */
 862
 863	return generic_permission(inode, mask);
 864}
 865
 866int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
 867{
 868	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 869	struct nilfs_inode_info *ii = NILFS_I(inode);
 870	int err;
 871
 872	spin_lock(&nilfs->ns_inode_lock);
 873	if (ii->i_bh == NULL) {
 874		spin_unlock(&nilfs->ns_inode_lock);
 875		err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
 876						  inode->i_ino, pbh);
 877		if (unlikely(err))
 878			return err;
 879		spin_lock(&nilfs->ns_inode_lock);
 880		if (ii->i_bh == NULL)
 881			ii->i_bh = *pbh;
 882		else {
 883			brelse(*pbh);
 884			*pbh = ii->i_bh;
 885		}
 886	} else
 887		*pbh = ii->i_bh;
 888
 889	get_bh(*pbh);
 890	spin_unlock(&nilfs->ns_inode_lock);
 891	return 0;
 892}
 893
 894int nilfs_inode_dirty(struct inode *inode)
 895{
 896	struct nilfs_inode_info *ii = NILFS_I(inode);
 897	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 898	int ret = 0;
 899
 900	if (!list_empty(&ii->i_dirty)) {
 901		spin_lock(&nilfs->ns_inode_lock);
 902		ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
 903			test_bit(NILFS_I_BUSY, &ii->i_state);
 904		spin_unlock(&nilfs->ns_inode_lock);
 905	}
 906	return ret;
 907}
 908
 909int nilfs_set_file_dirty(struct inode *inode, unsigned nr_dirty)
 910{
 911	struct nilfs_inode_info *ii = NILFS_I(inode);
 912	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 913
 914	atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);
 915
 916	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
 917		return 0;
 918
 919	spin_lock(&nilfs->ns_inode_lock);
 920	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
 921	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
 922		/* Because this routine may race with nilfs_dispose_list(),
 923		   we have to check NILFS_I_QUEUED here, too. */
 
 
 924		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
 925			/* This will happen when somebody is freeing
 926			   this inode. */
 927			nilfs_warning(inode->i_sb, __func__,
 928				      "cannot get inode (ino=%lu)\n",
 929				      inode->i_ino);
 
 
 930			spin_unlock(&nilfs->ns_inode_lock);
 931			return -EINVAL; /* NILFS_I_DIRTY may remain for
 932					   freeing inode */
 
 
 933		}
 934		list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
 935		set_bit(NILFS_I_QUEUED, &ii->i_state);
 936	}
 937	spin_unlock(&nilfs->ns_inode_lock);
 938	return 0;
 939}
 940
 941int __nilfs_mark_inode_dirty(struct inode *inode, int flags)
 942{
 943	struct buffer_head *ibh;
 944	int err;
 945
 946	err = nilfs_load_inode_block(inode, &ibh);
 947	if (unlikely(err)) {
 948		nilfs_warning(inode->i_sb, __func__,
 949			      "failed to reget inode block.\n");
 
 950		return err;
 951	}
 952	nilfs_update_inode(inode, ibh, flags);
 953	mark_buffer_dirty(ibh);
 954	nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
 955	brelse(ibh);
 956	return 0;
 957}
 958
 959/**
 960 * nilfs_dirty_inode - reflect changes on given inode to an inode block.
 961 * @inode: inode of the file to be registered.
 962 *
 963 * nilfs_dirty_inode() loads a inode block containing the specified
 964 * @inode and copies data from a nilfs_inode to a corresponding inode
 965 * entry in the inode block. This operation is excluded from the segment
 966 * construction. This function can be called both as a single operation
 967 * and as a part of indivisible file operations.
 968 */
 969void nilfs_dirty_inode(struct inode *inode, int flags)
 970{
 971	struct nilfs_transaction_info ti;
 972	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 973
 974	if (is_bad_inode(inode)) {
 975		nilfs_warning(inode->i_sb, __func__,
 976			      "tried to mark bad_inode dirty. ignored.\n");
 977		dump_stack();
 978		return;
 979	}
 980	if (mdi) {
 981		nilfs_mdt_mark_dirty(inode);
 982		return;
 983	}
 984	nilfs_transaction_begin(inode->i_sb, &ti, 0);
 985	__nilfs_mark_inode_dirty(inode, flags);
 986	nilfs_transaction_commit(inode->i_sb); /* never fails */
 987}
 988
 989int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 990		 __u64 start, __u64 len)
 991{
 992	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 993	__u64 logical = 0, phys = 0, size = 0;
 994	__u32 flags = 0;
 995	loff_t isize;
 996	sector_t blkoff, end_blkoff;
 997	sector_t delalloc_blkoff;
 998	unsigned long delalloc_blklen;
 999	unsigned int blkbits = inode->i_blkbits;
1000	int ret, n;
1001
1002	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1003	if (ret)
1004		return ret;
1005
1006	inode_lock(inode);
1007
1008	isize = i_size_read(inode);
1009
1010	blkoff = start >> blkbits;
1011	end_blkoff = (start + len - 1) >> blkbits;
1012
1013	delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
1014							&delalloc_blkoff);
1015
1016	do {
1017		__u64 blkphy;
1018		unsigned int maxblocks;
1019
1020		if (delalloc_blklen && blkoff == delalloc_blkoff) {
1021			if (size) {
1022				/* End of the current extent */
1023				ret = fiemap_fill_next_extent(
1024					fieinfo, logical, phys, size, flags);
1025				if (ret)
1026					break;
1027			}
1028			if (blkoff > end_blkoff)
1029				break;
1030
1031			flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
1032			logical = blkoff << blkbits;
1033			phys = 0;
1034			size = delalloc_blklen << blkbits;
1035
1036			blkoff = delalloc_blkoff + delalloc_blklen;
1037			delalloc_blklen = nilfs_find_uncommitted_extent(
1038				inode, blkoff, &delalloc_blkoff);
1039			continue;
1040		}
1041
1042		/*
1043		 * Limit the number of blocks that we look up so as
1044		 * not to get into the next delayed allocation extent.
1045		 */
1046		maxblocks = INT_MAX;
1047		if (delalloc_blklen)
1048			maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
1049					  maxblocks);
1050		blkphy = 0;
1051
1052		down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1053		n = nilfs_bmap_lookup_contig(
1054			NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
1055		up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1056
1057		if (n < 0) {
1058			int past_eof;
1059
1060			if (unlikely(n != -ENOENT))
1061				break; /* error */
1062
1063			/* HOLE */
1064			blkoff++;
1065			past_eof = ((blkoff << blkbits) >= isize);
1066
1067			if (size) {
1068				/* End of the current extent */
1069
1070				if (past_eof)
1071					flags |= FIEMAP_EXTENT_LAST;
1072
1073				ret = fiemap_fill_next_extent(
1074					fieinfo, logical, phys, size, flags);
1075				if (ret)
1076					break;
1077				size = 0;
1078			}
1079			if (blkoff > end_blkoff || past_eof)
1080				break;
1081		} else {
1082			if (size) {
1083				if (phys && blkphy << blkbits == phys + size) {
1084					/* The current extent goes on */
1085					size += n << blkbits;
1086				} else {
1087					/* Terminate the current extent */
1088					ret = fiemap_fill_next_extent(
1089						fieinfo, logical, phys, size,
1090						flags);
1091					if (ret || blkoff > end_blkoff)
1092						break;
1093
1094					/* Start another extent */
1095					flags = FIEMAP_EXTENT_MERGED;
1096					logical = blkoff << blkbits;
1097					phys = blkphy << blkbits;
1098					size = n << blkbits;
1099				}
1100			} else {
1101				/* Start a new extent */
1102				flags = FIEMAP_EXTENT_MERGED;
1103				logical = blkoff << blkbits;
1104				phys = blkphy << blkbits;
1105				size = n << blkbits;
1106			}
1107			blkoff += n;
1108		}
1109		cond_resched();
1110	} while (true);
1111
1112	/* If ret is 1 then we just hit the end of the extent array */
1113	if (ret == 1)
1114		ret = 0;
1115
1116	inode_unlock(inode);
1117	return ret;
1118}