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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}
v3.1
   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/writeback.h>
  28#include <linux/uio.h>
  29#include "nilfs.h"
  30#include "btnode.h"
  31#include "segment.h"
  32#include "page.h"
  33#include "mdt.h"
  34#include "cpfile.h"
  35#include "ifile.h"
  36
 
 
 
 
 
 
 
  37struct nilfs_iget_args {
  38	u64 ino;
  39	__u64 cno;
  40	struct nilfs_root *root;
  41	int for_gc;
  42};
  43
 
 
  44void nilfs_inode_add_blocks(struct inode *inode, int n)
  45{
  46	struct nilfs_root *root = NILFS_I(inode)->i_root;
  47
  48	inode_add_bytes(inode, (1 << inode->i_blkbits) * n);
  49	if (root)
  50		atomic_add(n, &root->blocks_count);
  51}
  52
  53void nilfs_inode_sub_blocks(struct inode *inode, int n)
  54{
  55	struct nilfs_root *root = NILFS_I(inode)->i_root;
  56
  57	inode_sub_bytes(inode, (1 << inode->i_blkbits) * n);
  58	if (root)
  59		atomic_sub(n, &root->blocks_count);
  60}
  61
  62/**
  63 * nilfs_get_block() - get a file block on the filesystem (callback function)
  64 * @inode - inode struct of the target file
  65 * @blkoff - file block number
  66 * @bh_result - buffer head to be mapped on
  67 * @create - indicate whether allocating the block or not when it has not
  68 *      been allocated yet.
  69 *
  70 * This function does not issue actual read request of the specified data
  71 * block. It is done by VFS.
  72 */
  73int nilfs_get_block(struct inode *inode, sector_t blkoff,
  74		    struct buffer_head *bh_result, int create)
  75{
  76	struct nilfs_inode_info *ii = NILFS_I(inode);
  77	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
  78	__u64 blknum = 0;
  79	int err = 0, ret;
  80	unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;
  81
  82	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  83	ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  84	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  85	if (ret >= 0) {	/* found */
  86		map_bh(bh_result, inode->i_sb, blknum);
  87		if (ret > 0)
  88			bh_result->b_size = (ret << inode->i_blkbits);
  89		goto out;
  90	}
  91	/* data block was not found */
  92	if (ret == -ENOENT && create) {
  93		struct nilfs_transaction_info ti;
  94
  95		bh_result->b_blocknr = 0;
  96		err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
  97		if (unlikely(err))
  98			goto out;
  99		err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
 100					(unsigned long)bh_result);
 101		if (unlikely(err != 0)) {
 102			if (err == -EEXIST) {
 103				/*
 104				 * The get_block() function could be called
 105				 * from multiple callers for an inode.
 106				 * However, the page having this block must
 107				 * be locked in this case.
 108				 */
 109				printk(KERN_WARNING
 110				       "nilfs_get_block: a race condition "
 111				       "while inserting a data block. "
 112				       "(inode number=%lu, file block "
 113				       "offset=%llu)\n",
 114				       inode->i_ino,
 115				       (unsigned long long)blkoff);
 116				err = 0;
 117			}
 118			nilfs_transaction_abort(inode->i_sb);
 119			goto out;
 120		}
 121		nilfs_mark_inode_dirty(inode);
 122		nilfs_transaction_commit(inode->i_sb); /* never fails */
 123		/* Error handling should be detailed */
 124		set_buffer_new(bh_result);
 125		set_buffer_delay(bh_result);
 126		map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
 127						      to proper value */
 
 128	} else if (ret == -ENOENT) {
 129		/* not found is not error (e.g. hole); must return without
 130		   the mapped state flag. */
 
 
 131		;
 132	} else {
 133		err = ret;
 134	}
 135
 136 out:
 137	return err;
 138}
 139
 140/**
 141 * nilfs_readpage() - implement readpage() method of nilfs_aops {}
 142 * address_space_operations.
 143 * @file - file struct of the file to be read
 144 * @page - the page to be read
 145 */
 146static int nilfs_readpage(struct file *file, struct page *page)
 147{
 148	return mpage_readpage(page, nilfs_get_block);
 149}
 150
 151/**
 152 * nilfs_readpages() - implement readpages() method of nilfs_aops {}
 153 * address_space_operations.
 154 * @file - file struct of the file to be read
 155 * @mapping - address_space struct used for reading multiple pages
 156 * @pages - the pages to be read
 157 * @nr_pages - number of pages to be read
 158 */
 159static int nilfs_readpages(struct file *file, struct address_space *mapping,
 160			   struct list_head *pages, unsigned nr_pages)
 161{
 162	return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
 163}
 164
 165static int nilfs_writepages(struct address_space *mapping,
 166			    struct writeback_control *wbc)
 167{
 168	struct inode *inode = mapping->host;
 169	int err = 0;
 170
 
 
 
 
 
 171	if (wbc->sync_mode == WB_SYNC_ALL)
 172		err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 173						    wbc->range_start,
 174						    wbc->range_end);
 175	return err;
 176}
 177
 178static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 179{
 180	struct inode *inode = page->mapping->host;
 181	int err;
 182
 
 
 
 
 
 
 
 
 
 
 
 
 183	redirty_page_for_writepage(wbc, page);
 184	unlock_page(page);
 185
 186	if (wbc->sync_mode == WB_SYNC_ALL) {
 187		err = nilfs_construct_segment(inode->i_sb);
 188		if (unlikely(err))
 189			return err;
 190	} else if (wbc->for_reclaim)
 191		nilfs_flush_segment(inode->i_sb, inode->i_ino);
 192
 193	return 0;
 194}
 195
 196static int nilfs_set_page_dirty(struct page *page)
 197{
 198	int ret = __set_page_dirty_buffers(page);
 
 
 
 
 
 199
 200	if (ret) {
 201		struct inode *inode = page->mapping->host;
 202		unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 203
 204		nilfs_set_file_dirty(inode, nr_dirty);
 205	}
 206	return ret;
 207}
 208
 
 
 
 
 
 
 
 
 
 
 209static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 210			     loff_t pos, unsigned len, unsigned flags,
 211			     struct page **pagep, void **fsdata)
 212
 213{
 214	struct inode *inode = mapping->host;
 215	int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 216
 217	if (unlikely(err))
 218		return err;
 219
 220	err = block_write_begin(mapping, pos, len, flags, pagep,
 221				nilfs_get_block);
 222	if (unlikely(err)) {
 223		loff_t isize = mapping->host->i_size;
 224		if (pos + len > isize)
 225			vmtruncate(mapping->host, isize);
 226
 227		nilfs_transaction_abort(inode->i_sb);
 228	}
 229	return err;
 230}
 231
 232static int nilfs_write_end(struct file *file, struct address_space *mapping,
 233			   loff_t pos, unsigned len, unsigned copied,
 234			   struct page *page, void *fsdata)
 235{
 236	struct inode *inode = mapping->host;
 237	unsigned start = pos & (PAGE_CACHE_SIZE - 1);
 238	unsigned nr_dirty;
 239	int err;
 240
 241	nr_dirty = nilfs_page_count_clean_buffers(page, start,
 242						  start + copied);
 243	copied = generic_write_end(file, mapping, pos, len, copied, page,
 244				   fsdata);
 245	nilfs_set_file_dirty(inode, nr_dirty);
 246	err = nilfs_transaction_commit(inode->i_sb);
 247	return err ? : copied;
 248}
 249
 250static ssize_t
 251nilfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
 252		loff_t offset, unsigned long nr_segs)
 253{
 254	struct file *file = iocb->ki_filp;
 255	struct inode *inode = file->f_mapping->host;
 256	ssize_t size;
 257
 258	if (rw == WRITE)
 259		return 0;
 260
 261	/* Needs synchronization with the cleaner */
 262	size = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
 263				  nilfs_get_block);
 264
 265	/*
 266	 * In case of error extending write may have instantiated a few
 267	 * blocks outside i_size. Trim these off again.
 268	 */
 269	if (unlikely((rw & WRITE) && size < 0)) {
 270		loff_t isize = i_size_read(inode);
 271		loff_t end = offset + iov_length(iov, nr_segs);
 272
 273		if (end > isize)
 274			vmtruncate(inode, isize);
 275	}
 276
 277	return size;
 278}
 279
 280const struct address_space_operations nilfs_aops = {
 281	.writepage		= nilfs_writepage,
 282	.readpage		= nilfs_readpage,
 283	.writepages		= nilfs_writepages,
 284	.set_page_dirty		= nilfs_set_page_dirty,
 285	.readpages		= nilfs_readpages,
 286	.write_begin		= nilfs_write_begin,
 287	.write_end		= nilfs_write_end,
 288	/* .releasepage		= nilfs_releasepage, */
 289	.invalidatepage		= block_invalidatepage,
 290	.direct_IO		= nilfs_direct_IO,
 291	.is_partially_uptodate  = block_is_partially_uptodate,
 292};
 293
 294struct inode *nilfs_new_inode(struct inode *dir, int mode)
 
 
 
 
 
 
 
 
 
 
 
 295{
 296	struct super_block *sb = dir->i_sb;
 297	struct the_nilfs *nilfs = sb->s_fs_info;
 298	struct inode *inode;
 299	struct nilfs_inode_info *ii;
 300	struct nilfs_root *root;
 301	int err = -ENOMEM;
 302	ino_t ino;
 303
 304	inode = new_inode(sb);
 305	if (unlikely(!inode))
 306		goto failed;
 307
 308	mapping_set_gfp_mask(inode->i_mapping,
 309			     mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 310
 311	root = NILFS_I(dir)->i_root;
 312	ii = NILFS_I(inode);
 313	ii->i_state = 1 << NILFS_I_NEW;
 314	ii->i_root = root;
 315
 316	err = nilfs_ifile_create_inode(root->ifile, &ino, &ii->i_bh);
 317	if (unlikely(err))
 318		goto failed_ifile_create_inode;
 319	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
 320
 321	atomic_inc(&root->inodes_count);
 322	inode_init_owner(inode, dir, mode);
 323	inode->i_ino = ino;
 324	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 325
 326	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
 327		err = nilfs_bmap_read(ii->i_bmap, NULL);
 328		if (err < 0)
 329			goto failed_bmap;
 330
 331		set_bit(NILFS_I_BMAP, &ii->i_state);
 332		/* No lock is needed; iget() ensures it. */
 333	}
 334
 335	ii->i_flags = nilfs_mask_flags(
 336		mode, NILFS_I(dir)->i_flags & NILFS_FL_INHERITED);
 337
 338	/* ii->i_file_acl = 0; */
 339	/* ii->i_dir_acl = 0; */
 340	ii->i_dir_start_lookup = 0;
 341	nilfs_set_inode_flags(inode);
 342	spin_lock(&nilfs->ns_next_gen_lock);
 343	inode->i_generation = nilfs->ns_next_generation++;
 344	spin_unlock(&nilfs->ns_next_gen_lock);
 345	insert_inode_hash(inode);
 
 
 
 346
 347	err = nilfs_init_acl(inode, dir);
 348	if (unlikely(err))
 349		goto failed_acl; /* never occur. When supporting
 350				    nilfs_init_acl(), proper cancellation of
 351				    above jobs should be considered */
 
 
 352
 353	return inode;
 354
 355 failed_acl:
 356 failed_bmap:
 357	inode->i_nlink = 0;
 358	iput(inode);  /* raw_inode will be deleted through
 359			 generic_delete_inode() */
 
 
 360	goto failed;
 361
 362 failed_ifile_create_inode:
 363	make_bad_inode(inode);
 364	iput(inode);  /* if i_nlink == 1, generic_forget_inode() will be
 365			 called */
 366 failed:
 367	return ERR_PTR(err);
 368}
 369
 370void nilfs_set_inode_flags(struct inode *inode)
 371{
 372	unsigned int flags = NILFS_I(inode)->i_flags;
 
 373
 374	inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME |
 375			    S_DIRSYNC);
 376	if (flags & FS_SYNC_FL)
 377		inode->i_flags |= S_SYNC;
 378	if (flags & FS_APPEND_FL)
 379		inode->i_flags |= S_APPEND;
 380	if (flags & FS_IMMUTABLE_FL)
 381		inode->i_flags |= S_IMMUTABLE;
 382	if (flags & FS_NOATIME_FL)
 383		inode->i_flags |= S_NOATIME;
 384	if (flags & FS_DIRSYNC_FL)
 385		inode->i_flags |= S_DIRSYNC;
 386	mapping_set_gfp_mask(inode->i_mapping,
 387			     mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 388}
 389
 390int nilfs_read_inode_common(struct inode *inode,
 391			    struct nilfs_inode *raw_inode)
 392{
 393	struct nilfs_inode_info *ii = NILFS_I(inode);
 394	int err;
 395
 396	inode->i_mode = le16_to_cpu(raw_inode->i_mode);
 397	inode->i_uid = (uid_t)le32_to_cpu(raw_inode->i_uid);
 398	inode->i_gid = (gid_t)le32_to_cpu(raw_inode->i_gid);
 399	inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
 400	inode->i_size = le64_to_cpu(raw_inode->i_size);
 401	inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 402	inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
 403	inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 404	inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 405	inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 406	inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 407	if (inode->i_nlink == 0 && inode->i_mode == 0)
 408		return -EINVAL; /* this inode is deleted */
 409
 410	inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 411	ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 412#if 0
 413	ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 414	ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 415		0 : le32_to_cpu(raw_inode->i_dir_acl);
 416#endif
 417	ii->i_dir_start_lookup = 0;
 418	inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 419
 420	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 421	    S_ISLNK(inode->i_mode)) {
 422		err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 423		if (err < 0)
 424			return err;
 425		set_bit(NILFS_I_BMAP, &ii->i_state);
 426		/* No lock is needed; iget() ensures it. */
 427	}
 428	return 0;
 429}
 430
 431static int __nilfs_read_inode(struct super_block *sb,
 432			      struct nilfs_root *root, unsigned long ino,
 433			      struct inode *inode)
 434{
 435	struct the_nilfs *nilfs = sb->s_fs_info;
 436	struct buffer_head *bh;
 437	struct nilfs_inode *raw_inode;
 438	int err;
 439
 440	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 441	err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
 442	if (unlikely(err))
 443		goto bad_inode;
 444
 445	raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
 446
 447	err = nilfs_read_inode_common(inode, raw_inode);
 448	if (err)
 449		goto failed_unmap;
 450
 451	if (S_ISREG(inode->i_mode)) {
 452		inode->i_op = &nilfs_file_inode_operations;
 453		inode->i_fop = &nilfs_file_operations;
 454		inode->i_mapping->a_ops = &nilfs_aops;
 455	} else if (S_ISDIR(inode->i_mode)) {
 456		inode->i_op = &nilfs_dir_inode_operations;
 457		inode->i_fop = &nilfs_dir_operations;
 458		inode->i_mapping->a_ops = &nilfs_aops;
 459	} else if (S_ISLNK(inode->i_mode)) {
 460		inode->i_op = &nilfs_symlink_inode_operations;
 
 461		inode->i_mapping->a_ops = &nilfs_aops;
 462	} else {
 463		inode->i_op = &nilfs_special_inode_operations;
 464		init_special_inode(
 465			inode, inode->i_mode,
 466			huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 467	}
 468	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 469	brelse(bh);
 470	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 471	nilfs_set_inode_flags(inode);
 
 
 472	return 0;
 473
 474 failed_unmap:
 475	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 476	brelse(bh);
 477
 478 bad_inode:
 479	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 480	return err;
 481}
 482
 483static int nilfs_iget_test(struct inode *inode, void *opaque)
 484{
 485	struct nilfs_iget_args *args = opaque;
 486	struct nilfs_inode_info *ii;
 487
 488	if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
 489		return 0;
 490
 491	ii = NILFS_I(inode);
 492	if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
 493		return !args->for_gc;
 494
 495	return args->for_gc && args->cno == ii->i_cno;
 496}
 497
 498static int nilfs_iget_set(struct inode *inode, void *opaque)
 499{
 500	struct nilfs_iget_args *args = opaque;
 501
 502	inode->i_ino = args->ino;
 503	if (args->for_gc) {
 504		NILFS_I(inode)->i_state = 1 << NILFS_I_GCINODE;
 505		NILFS_I(inode)->i_cno = args->cno;
 506		NILFS_I(inode)->i_root = NULL;
 507	} else {
 508		if (args->root && args->ino == NILFS_ROOT_INO)
 509			nilfs_get_root(args->root);
 510		NILFS_I(inode)->i_root = args->root;
 511	}
 512	return 0;
 513}
 514
 515struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
 516			    unsigned long ino)
 517{
 518	struct nilfs_iget_args args = {
 519		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 520	};
 521
 522	return ilookup5(sb, ino, nilfs_iget_test, &args);
 523}
 524
 525struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
 526				unsigned long ino)
 527{
 528	struct nilfs_iget_args args = {
 529		.ino = ino, .root = root, .cno = 0, .for_gc = 0
 530	};
 531
 532	return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 533}
 534
 535struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
 536			 unsigned long ino)
 537{
 538	struct inode *inode;
 539	int err;
 540
 541	inode = nilfs_iget_locked(sb, root, ino);
 542	if (unlikely(!inode))
 543		return ERR_PTR(-ENOMEM);
 544	if (!(inode->i_state & I_NEW))
 545		return inode;
 546
 547	err = __nilfs_read_inode(sb, root, ino, inode);
 548	if (unlikely(err)) {
 549		iget_failed(inode);
 550		return ERR_PTR(err);
 551	}
 552	unlock_new_inode(inode);
 553	return inode;
 554}
 555
 556struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
 557				__u64 cno)
 558{
 559	struct nilfs_iget_args args = {
 560		.ino = ino, .root = NULL, .cno = cno, .for_gc = 1
 561	};
 562	struct inode *inode;
 563	int err;
 564
 565	inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 566	if (unlikely(!inode))
 567		return ERR_PTR(-ENOMEM);
 568	if (!(inode->i_state & I_NEW))
 569		return inode;
 570
 571	err = nilfs_init_gcinode(inode);
 572	if (unlikely(err)) {
 573		iget_failed(inode);
 574		return ERR_PTR(err);
 575	}
 576	unlock_new_inode(inode);
 577	return inode;
 578}
 579
 580void nilfs_write_inode_common(struct inode *inode,
 581			      struct nilfs_inode *raw_inode, int has_bmap)
 582{
 583	struct nilfs_inode_info *ii = NILFS_I(inode);
 584
 585	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 586	raw_inode->i_uid = cpu_to_le32(inode->i_uid);
 587	raw_inode->i_gid = cpu_to_le32(inode->i_gid);
 588	raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 589	raw_inode->i_size = cpu_to_le64(inode->i_size);
 590	raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 591	raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
 592	raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 593	raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 594	raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 595
 596	raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 597	raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 598
 599	if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) {
 600		struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 601
 602		/* zero-fill unused portion in the case of super root block */
 603		raw_inode->i_xattr = 0;
 604		raw_inode->i_pad = 0;
 605		memset((void *)raw_inode + sizeof(*raw_inode), 0,
 606		       nilfs->ns_inode_size - sizeof(*raw_inode));
 607	}
 608
 609	if (has_bmap)
 610		nilfs_bmap_write(ii->i_bmap, raw_inode);
 611	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 612		raw_inode->i_device_code =
 613			cpu_to_le64(huge_encode_dev(inode->i_rdev));
 614	/* When extending inode, nilfs->ns_inode_size should be checked
 615	   for substitutions of appended fields */
 
 
 616}
 617
 618void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh)
 619{
 620	ino_t ino = inode->i_ino;
 621	struct nilfs_inode_info *ii = NILFS_I(inode);
 622	struct inode *ifile = ii->i_root->ifile;
 623	struct nilfs_inode *raw_inode;
 624
 625	raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
 626
 627	if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 628		memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
 629	set_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
 
 630
 631	nilfs_write_inode_common(inode, raw_inode, 0);
 632		/* XXX: call with has_bmap = 0 is a workaround to avoid
 633		   deadlock of bmap. This delays update of i_bmap to just
 634		   before writing */
 
 
 
 635	nilfs_ifile_unmap_inode(ifile, ino, ibh);
 636}
 637
 638#define NILFS_MAX_TRUNCATE_BLOCKS	16384  /* 64MB for 4KB block */
 639
 640static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 641				unsigned long from)
 642{
 643	unsigned long b;
 644	int ret;
 645
 646	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 647		return;
 648repeat:
 649	ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 650	if (ret == -ENOENT)
 651		return;
 652	else if (ret < 0)
 653		goto failed;
 654
 655	if (b < from)
 656		return;
 657
 658	b -= min_t(unsigned long, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 659	ret = nilfs_bmap_truncate(ii->i_bmap, b);
 660	nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 661	if (!ret || (ret == -ENOMEM &&
 662		     nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 663		goto repeat;
 664
 665failed:
 666	nilfs_warning(ii->vfs_inode.i_sb, __func__,
 667		      "failed to truncate bmap (ino=%lu, err=%d)",
 668		      ii->vfs_inode.i_ino, ret);
 669}
 670
 671void nilfs_truncate(struct inode *inode)
 672{
 673	unsigned long blkoff;
 674	unsigned int blocksize;
 675	struct nilfs_transaction_info ti;
 676	struct super_block *sb = inode->i_sb;
 677	struct nilfs_inode_info *ii = NILFS_I(inode);
 678
 679	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 680		return;
 681	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 682		return;
 683
 684	blocksize = sb->s_blocksize;
 685	blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 686	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 687
 688	block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 689
 690	nilfs_truncate_bmap(ii, blkoff);
 691
 692	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 693	if (IS_SYNC(inode))
 694		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 695
 696	nilfs_mark_inode_dirty(inode);
 697	nilfs_set_file_dirty(inode, 0);
 698	nilfs_transaction_commit(sb);
 699	/* May construct a logical segment and may fail in sync mode.
 700	   But truncate has no return value. */
 
 
 701}
 702
 703static void nilfs_clear_inode(struct inode *inode)
 704{
 705	struct nilfs_inode_info *ii = NILFS_I(inode);
 706	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 707
 708	/*
 709	 * Free resources allocated in nilfs_read_inode(), here.
 710	 */
 711	BUG_ON(!list_empty(&ii->i_dirty));
 712	brelse(ii->i_bh);
 713	ii->i_bh = NULL;
 714
 715	if (mdi && mdi->mi_palloc_cache)
 716		nilfs_palloc_destroy_cache(inode);
 717
 718	if (test_bit(NILFS_I_BMAP, &ii->i_state))
 719		nilfs_bmap_clear(ii->i_bmap);
 720
 721	nilfs_btnode_cache_clear(&ii->i_btnode_cache);
 722
 723	if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
 724		nilfs_put_root(ii->i_root);
 725}
 726
 727void nilfs_evict_inode(struct inode *inode)
 728{
 729	struct nilfs_transaction_info ti;
 730	struct super_block *sb = inode->i_sb;
 731	struct nilfs_inode_info *ii = NILFS_I(inode);
 732	int ret;
 733
 734	if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
 735		if (inode->i_data.nrpages)
 736			truncate_inode_pages(&inode->i_data, 0);
 737		end_writeback(inode);
 738		nilfs_clear_inode(inode);
 739		return;
 740	}
 741	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 742
 743	if (inode->i_data.nrpages)
 744		truncate_inode_pages(&inode->i_data, 0);
 745
 746	/* TODO: some of the following operations may fail.  */
 747	nilfs_truncate_bmap(ii, 0);
 748	nilfs_mark_inode_dirty(inode);
 749	end_writeback(inode);
 750
 751	ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
 752	if (!ret)
 753		atomic_dec(&ii->i_root->inodes_count);
 754
 755	nilfs_clear_inode(inode);
 756
 757	if (IS_SYNC(inode))
 758		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 759	nilfs_transaction_commit(sb);
 760	/* May construct a logical segment and may fail in sync mode.
 761	   But delete_inode has no return value. */
 
 
 762}
 763
 764int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 765{
 766	struct nilfs_transaction_info ti;
 767	struct inode *inode = dentry->d_inode;
 768	struct super_block *sb = inode->i_sb;
 769	int err;
 770
 771	err = inode_change_ok(inode, iattr);
 772	if (err)
 773		return err;
 774
 775	err = nilfs_transaction_begin(sb, &ti, 0);
 776	if (unlikely(err))
 777		return err;
 778
 779	if ((iattr->ia_valid & ATTR_SIZE) &&
 780	    iattr->ia_size != i_size_read(inode)) {
 781		inode_dio_wait(inode);
 782
 783		err = vmtruncate(inode, iattr->ia_size);
 784		if (unlikely(err))
 785			goto out_err;
 786	}
 787
 788	setattr_copy(inode, iattr);
 789	mark_inode_dirty(inode);
 790
 791	if (iattr->ia_valid & ATTR_MODE) {
 792		err = nilfs_acl_chmod(inode);
 793		if (unlikely(err))
 794			goto out_err;
 795	}
 796
 797	return nilfs_transaction_commit(sb);
 798
 799out_err:
 800	nilfs_transaction_abort(sb);
 801	return err;
 802}
 803
 804int nilfs_permission(struct inode *inode, int mask)
 805{
 806	struct nilfs_root *root = NILFS_I(inode)->i_root;
 
 807	if ((mask & MAY_WRITE) && root &&
 808	    root->cno != NILFS_CPTREE_CURRENT_CNO)
 809		return -EROFS; /* snapshot is not writable */
 810
 811	return generic_permission(inode, mask);
 812}
 813
 814int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
 815{
 816	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 817	struct nilfs_inode_info *ii = NILFS_I(inode);
 818	int err;
 819
 820	spin_lock(&nilfs->ns_inode_lock);
 821	if (ii->i_bh == NULL) {
 822		spin_unlock(&nilfs->ns_inode_lock);
 823		err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
 824						  inode->i_ino, pbh);
 825		if (unlikely(err))
 826			return err;
 827		spin_lock(&nilfs->ns_inode_lock);
 828		if (ii->i_bh == NULL)
 829			ii->i_bh = *pbh;
 830		else {
 831			brelse(*pbh);
 832			*pbh = ii->i_bh;
 833		}
 834	} else
 835		*pbh = ii->i_bh;
 836
 837	get_bh(*pbh);
 838	spin_unlock(&nilfs->ns_inode_lock);
 839	return 0;
 840}
 841
 842int nilfs_inode_dirty(struct inode *inode)
 843{
 844	struct nilfs_inode_info *ii = NILFS_I(inode);
 845	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 846	int ret = 0;
 847
 848	if (!list_empty(&ii->i_dirty)) {
 849		spin_lock(&nilfs->ns_inode_lock);
 850		ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
 851			test_bit(NILFS_I_BUSY, &ii->i_state);
 852		spin_unlock(&nilfs->ns_inode_lock);
 853	}
 854	return ret;
 855}
 856
 857int nilfs_set_file_dirty(struct inode *inode, unsigned nr_dirty)
 858{
 859	struct nilfs_inode_info *ii = NILFS_I(inode);
 860	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 861
 862	atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);
 863
 864	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
 865		return 0;
 866
 867	spin_lock(&nilfs->ns_inode_lock);
 868	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
 869	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
 870		/* Because this routine may race with nilfs_dispose_list(),
 871		   we have to check NILFS_I_QUEUED here, too. */
 
 
 872		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
 873			/* This will happen when somebody is freeing
 874			   this inode. */
 875			nilfs_warning(inode->i_sb, __func__,
 876				      "cannot get inode (ino=%lu)\n",
 877				      inode->i_ino);
 
 
 878			spin_unlock(&nilfs->ns_inode_lock);
 879			return -EINVAL; /* NILFS_I_DIRTY may remain for
 880					   freeing inode */
 
 
 881		}
 882		list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
 883		set_bit(NILFS_I_QUEUED, &ii->i_state);
 884	}
 885	spin_unlock(&nilfs->ns_inode_lock);
 886	return 0;
 887}
 888
 889int nilfs_mark_inode_dirty(struct inode *inode)
 890{
 891	struct buffer_head *ibh;
 892	int err;
 893
 894	err = nilfs_load_inode_block(inode, &ibh);
 895	if (unlikely(err)) {
 896		nilfs_warning(inode->i_sb, __func__,
 897			      "failed to reget inode block.\n");
 
 898		return err;
 899	}
 900	nilfs_update_inode(inode, ibh);
 901	mark_buffer_dirty(ibh);
 902	nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
 903	brelse(ibh);
 904	return 0;
 905}
 906
 907/**
 908 * nilfs_dirty_inode - reflect changes on given inode to an inode block.
 909 * @inode: inode of the file to be registered.
 910 *
 911 * nilfs_dirty_inode() loads a inode block containing the specified
 912 * @inode and copies data from a nilfs_inode to a corresponding inode
 913 * entry in the inode block. This operation is excluded from the segment
 914 * construction. This function can be called both as a single operation
 915 * and as a part of indivisible file operations.
 916 */
 917void nilfs_dirty_inode(struct inode *inode, int flags)
 918{
 919	struct nilfs_transaction_info ti;
 920	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 921
 922	if (is_bad_inode(inode)) {
 923		nilfs_warning(inode->i_sb, __func__,
 924			      "tried to mark bad_inode dirty. ignored.\n");
 925		dump_stack();
 926		return;
 927	}
 928	if (mdi) {
 929		nilfs_mdt_mark_dirty(inode);
 930		return;
 931	}
 932	nilfs_transaction_begin(inode->i_sb, &ti, 0);
 933	nilfs_mark_inode_dirty(inode);
 934	nilfs_transaction_commit(inode->i_sb); /* never fails */
 935}
 936
 937int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 938		 __u64 start, __u64 len)
 939{
 940	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 941	__u64 logical = 0, phys = 0, size = 0;
 942	__u32 flags = 0;
 943	loff_t isize;
 944	sector_t blkoff, end_blkoff;
 945	sector_t delalloc_blkoff;
 946	unsigned long delalloc_blklen;
 947	unsigned int blkbits = inode->i_blkbits;
 948	int ret, n;
 949
 950	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
 951	if (ret)
 952		return ret;
 953
 954	mutex_lock(&inode->i_mutex);
 955
 956	isize = i_size_read(inode);
 957
 958	blkoff = start >> blkbits;
 959	end_blkoff = (start + len - 1) >> blkbits;
 960
 961	delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
 962							&delalloc_blkoff);
 963
 964	do {
 965		__u64 blkphy;
 966		unsigned int maxblocks;
 967
 968		if (delalloc_blklen && blkoff == delalloc_blkoff) {
 969			if (size) {
 970				/* End of the current extent */
 971				ret = fiemap_fill_next_extent(
 972					fieinfo, logical, phys, size, flags);
 973				if (ret)
 974					break;
 975			}
 976			if (blkoff > end_blkoff)
 977				break;
 978
 979			flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
 980			logical = blkoff << blkbits;
 981			phys = 0;
 982			size = delalloc_blklen << blkbits;
 983
 984			blkoff = delalloc_blkoff + delalloc_blklen;
 985			delalloc_blklen = nilfs_find_uncommitted_extent(
 986				inode, blkoff, &delalloc_blkoff);
 987			continue;
 988		}
 989
 990		/*
 991		 * Limit the number of blocks that we look up so as
 992		 * not to get into the next delayed allocation extent.
 993		 */
 994		maxblocks = INT_MAX;
 995		if (delalloc_blklen)
 996			maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
 997					  maxblocks);
 998		blkphy = 0;
 999
1000		down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1001		n = nilfs_bmap_lookup_contig(
1002			NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
1003		up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1004
1005		if (n < 0) {
1006			int past_eof;
1007
1008			if (unlikely(n != -ENOENT))
1009				break; /* error */
1010
1011			/* HOLE */
1012			blkoff++;
1013			past_eof = ((blkoff << blkbits) >= isize);
1014
1015			if (size) {
1016				/* End of the current extent */
1017
1018				if (past_eof)
1019					flags |= FIEMAP_EXTENT_LAST;
1020
1021				ret = fiemap_fill_next_extent(
1022					fieinfo, logical, phys, size, flags);
1023				if (ret)
1024					break;
1025				size = 0;
1026			}
1027			if (blkoff > end_blkoff || past_eof)
1028				break;
1029		} else {
1030			if (size) {
1031				if (phys && blkphy << blkbits == phys + size) {
1032					/* The current extent goes on */
1033					size += n << blkbits;
1034				} else {
1035					/* Terminate the current extent */
1036					ret = fiemap_fill_next_extent(
1037						fieinfo, logical, phys, size,
1038						flags);
1039					if (ret || blkoff > end_blkoff)
1040						break;
1041
1042					/* Start another extent */
1043					flags = FIEMAP_EXTENT_MERGED;
1044					logical = blkoff << blkbits;
1045					phys = blkphy << blkbits;
1046					size = n << blkbits;
1047				}
1048			} else {
1049				/* Start a new extent */
1050				flags = FIEMAP_EXTENT_MERGED;
1051				logical = blkoff << blkbits;
1052				phys = blkphy << blkbits;
1053				size = n << blkbits;
1054			}
1055			blkoff += n;
1056		}
1057		cond_resched();
1058	} while (true);
1059
1060	/* If ret is 1 then we just hit the end of the extent array */
1061	if (ret == 1)
1062		ret = 0;
1063
1064	mutex_unlock(&inode->i_mutex);
1065	return ret;
1066}