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v6.8
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * NILFS inode operations.
   4 *
   5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   6 *
   7 * Written by Ryusuke Konishi.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   8 *
   9 */
  10
  11#include <linux/buffer_head.h>
  12#include <linux/gfp.h>
  13#include <linux/mpage.h>
  14#include <linux/pagemap.h>
  15#include <linux/writeback.h>
  16#include <linux/uio.h>
  17#include <linux/fiemap.h>
  18#include "nilfs.h"
  19#include "btnode.h"
  20#include "segment.h"
  21#include "page.h"
  22#include "mdt.h"
  23#include "cpfile.h"
  24#include "ifile.h"
  25
  26/**
  27 * struct nilfs_iget_args - arguments used during comparison between inodes
  28 * @ino: inode number
  29 * @cno: checkpoint number
  30 * @root: pointer on NILFS root object (mounted checkpoint)
  31 * @for_gc: inode for GC flag
  32 * @for_btnc: inode for B-tree node cache flag
  33 * @for_shadow: inode for shadowed page cache flag
  34 */
  35struct nilfs_iget_args {
  36	u64 ino;
  37	__u64 cno;
  38	struct nilfs_root *root;
  39	bool for_gc;
  40	bool for_btnc;
  41	bool for_shadow;
  42};
  43
  44static int nilfs_iget_test(struct inode *inode, void *opaque);
  45
  46void nilfs_inode_add_blocks(struct inode *inode, int n)
  47{
  48	struct nilfs_root *root = NILFS_I(inode)->i_root;
  49
  50	inode_add_bytes(inode, i_blocksize(inode) * n);
  51	if (root)
  52		atomic64_add(n, &root->blocks_count);
  53}
  54
  55void nilfs_inode_sub_blocks(struct inode *inode, int n)
  56{
  57	struct nilfs_root *root = NILFS_I(inode)->i_root;
  58
  59	inode_sub_bytes(inode, i_blocksize(inode) * n);
  60	if (root)
  61		atomic64_sub(n, &root->blocks_count);
  62}
  63
  64/**
  65 * nilfs_get_block() - get a file block on the filesystem (callback function)
  66 * @inode: inode struct of the target file
  67 * @blkoff: file block number
  68 * @bh_result: buffer head to be mapped on
  69 * @create: indicate whether allocating the block or not when it has not
  70 *      been allocated yet.
  71 *
  72 * This function does not issue actual read request of the specified data
  73 * block. It is done by VFS.
  74 */
  75int nilfs_get_block(struct inode *inode, sector_t blkoff,
  76		    struct buffer_head *bh_result, int create)
  77{
  78	struct nilfs_inode_info *ii = NILFS_I(inode);
  79	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
  80	__u64 blknum = 0;
  81	int err = 0, ret;
  82	unsigned int maxblocks = bh_result->b_size >> inode->i_blkbits;
  83
  84	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  85	ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  86	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  87	if (ret >= 0) {	/* found */
  88		map_bh(bh_result, inode->i_sb, blknum);
  89		if (ret > 0)
  90			bh_result->b_size = (ret << inode->i_blkbits);
  91		goto out;
  92	}
  93	/* data block was not found */
  94	if (ret == -ENOENT && create) {
  95		struct nilfs_transaction_info ti;
  96
  97		bh_result->b_blocknr = 0;
  98		err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
  99		if (unlikely(err))
 100			goto out;
 101		err = nilfs_bmap_insert(ii->i_bmap, blkoff,
 102					(unsigned long)bh_result);
 103		if (unlikely(err != 0)) {
 104			if (err == -EEXIST) {
 105				/*
 106				 * The get_block() function could be called
 107				 * from multiple callers for an inode.
 108				 * However, the page having this block must
 109				 * be locked in this case.
 110				 */
 111				nilfs_warn(inode->i_sb,
 112					   "%s (ino=%lu): a race condition while inserting a data block at offset=%llu",
 113					   __func__, inode->i_ino,
 114					   (unsigned long long)blkoff);
 
 
 
 115				err = 0;
 116			}
 117			nilfs_transaction_abort(inode->i_sb);
 118			goto out;
 119		}
 120		nilfs_mark_inode_dirty_sync(inode);
 121		nilfs_transaction_commit(inode->i_sb); /* never fails */
 122		/* Error handling should be detailed */
 123		set_buffer_new(bh_result);
 124		set_buffer_delay(bh_result);
 125		map_bh(bh_result, inode->i_sb, 0);
 126		/* Disk block number must be changed to proper value */
 127
 128	} else if (ret == -ENOENT) {
 129		/*
 130		 * not found is not error (e.g. hole); must return without
 131		 * the mapped state flag.
 132		 */
 133		;
 134	} else {
 135		err = ret;
 136	}
 137
 138 out:
 139	return err;
 140}
 141
 142/**
 143 * nilfs_read_folio() - implement read_folio() method of nilfs_aops {}
 144 * address_space_operations.
 145 * @file: file struct of the file to be read
 146 * @folio: the folio to be read
 147 */
 148static int nilfs_read_folio(struct file *file, struct folio *folio)
 149{
 150	return mpage_read_folio(folio, nilfs_get_block);
 151}
 152
 153static void nilfs_readahead(struct readahead_control *rac)
 
 
 
 
 
 
 
 
 
 154{
 155	mpage_readahead(rac, nilfs_get_block);
 156}
 157
 158static int nilfs_writepages(struct address_space *mapping,
 159			    struct writeback_control *wbc)
 160{
 161	struct inode *inode = mapping->host;
 162	int err = 0;
 163
 164	if (sb_rdonly(inode->i_sb)) {
 165		nilfs_clear_dirty_pages(mapping, false);
 166		return -EROFS;
 167	}
 168
 169	if (wbc->sync_mode == WB_SYNC_ALL)
 170		err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 171						    wbc->range_start,
 172						    wbc->range_end);
 173	return err;
 174}
 175
 176static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 177{
 178	struct folio *folio = page_folio(page);
 179	struct inode *inode = folio->mapping->host;
 180	int err;
 181
 182	if (sb_rdonly(inode->i_sb)) {
 183		/*
 184		 * It means that filesystem was remounted in read-only
 185		 * mode because of error or metadata corruption. But we
 186		 * have dirty pages that try to be flushed in background.
 187		 * So, here we simply discard this dirty page.
 188		 */
 189		nilfs_clear_folio_dirty(folio, false);
 190		folio_unlock(folio);
 191		return -EROFS;
 192	}
 193
 194	folio_redirty_for_writepage(wbc, folio);
 195	folio_unlock(folio);
 196
 197	if (wbc->sync_mode == WB_SYNC_ALL) {
 198		err = nilfs_construct_segment(inode->i_sb);
 199		if (unlikely(err))
 200			return err;
 201	} else if (wbc->for_reclaim)
 202		nilfs_flush_segment(inode->i_sb, inode->i_ino);
 203
 204	return 0;
 205}
 206
 207static bool nilfs_dirty_folio(struct address_space *mapping,
 208		struct folio *folio)
 209{
 210	struct inode *inode = mapping->host;
 211	struct buffer_head *head;
 212	unsigned int nr_dirty = 0;
 213	bool ret = filemap_dirty_folio(mapping, folio);
 214
 215	/*
 216	 * The page may not be locked, eg if called from try_to_unmap_one()
 217	 */
 218	spin_lock(&mapping->i_private_lock);
 219	head = folio_buffers(folio);
 220	if (head) {
 221		struct buffer_head *bh = head;
 222
 
 
 
 
 
 
 
 
 223		do {
 224			/* Do not mark hole blocks dirty */
 225			if (buffer_dirty(bh) || !buffer_mapped(bh))
 226				continue;
 227
 228			set_buffer_dirty(bh);
 229			nr_dirty++;
 230		} while (bh = bh->b_this_page, bh != head);
 
 
 
 231	} else if (ret) {
 232		nr_dirty = 1 << (folio_shift(folio) - inode->i_blkbits);
 233	}
 234	spin_unlock(&mapping->i_private_lock);
 235
 236	if (nr_dirty)
 237		nilfs_set_file_dirty(inode, nr_dirty);
 
 238	return ret;
 239}
 240
 241void nilfs_write_failed(struct address_space *mapping, loff_t to)
 242{
 243	struct inode *inode = mapping->host;
 244
 245	if (to > inode->i_size) {
 246		truncate_pagecache(inode, inode->i_size);
 247		nilfs_truncate(inode);
 248	}
 249}
 250
 251static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 252			     loff_t pos, unsigned len,
 253			     struct page **pagep, void **fsdata)
 254
 255{
 256	struct inode *inode = mapping->host;
 257	int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 258
 259	if (unlikely(err))
 260		return err;
 261
 262	err = block_write_begin(mapping, pos, len, pagep, nilfs_get_block);
 
 263	if (unlikely(err)) {
 264		nilfs_write_failed(mapping, pos + len);
 265		nilfs_transaction_abort(inode->i_sb);
 266	}
 267	return err;
 268}
 269
 270static int nilfs_write_end(struct file *file, struct address_space *mapping,
 271			   loff_t pos, unsigned len, unsigned copied,
 272			   struct page *page, void *fsdata)
 273{
 274	struct inode *inode = mapping->host;
 275	unsigned int start = pos & (PAGE_SIZE - 1);
 276	unsigned int nr_dirty;
 277	int err;
 278
 279	nr_dirty = nilfs_page_count_clean_buffers(page, start,
 280						  start + copied);
 281	copied = generic_write_end(file, mapping, pos, len, copied, page,
 282				   fsdata);
 283	nilfs_set_file_dirty(inode, nr_dirty);
 284	err = nilfs_transaction_commit(inode->i_sb);
 285	return err ? : copied;
 286}
 287
 288static ssize_t
 289nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 290{
 291	struct inode *inode = file_inode(iocb->ki_filp);
 292
 293	if (iov_iter_rw(iter) == WRITE)
 294		return 0;
 295
 296	/* Needs synchronization with the cleaner */
 297	return blockdev_direct_IO(iocb, inode, iter, nilfs_get_block);
 298}
 299
 300const struct address_space_operations nilfs_aops = {
 301	.writepage		= nilfs_writepage,
 302	.read_folio		= nilfs_read_folio,
 303	.writepages		= nilfs_writepages,
 304	.dirty_folio		= nilfs_dirty_folio,
 305	.readahead		= nilfs_readahead,
 306	.write_begin		= nilfs_write_begin,
 307	.write_end		= nilfs_write_end,
 308	.invalidate_folio	= block_invalidate_folio,
 
 309	.direct_IO		= nilfs_direct_IO,
 310	.is_partially_uptodate  = block_is_partially_uptodate,
 311};
 312
 313static int nilfs_insert_inode_locked(struct inode *inode,
 314				     struct nilfs_root *root,
 315				     unsigned long ino)
 316{
 317	struct nilfs_iget_args args = {
 318		.ino = ino, .root = root, .cno = 0, .for_gc = false,
 319		.for_btnc = false, .for_shadow = false
 320	};
 321
 322	return insert_inode_locked4(inode, ino, nilfs_iget_test, &args);
 323}
 324
 325struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 326{
 327	struct super_block *sb = dir->i_sb;
 328	struct the_nilfs *nilfs = sb->s_fs_info;
 329	struct inode *inode;
 330	struct nilfs_inode_info *ii;
 331	struct nilfs_root *root;
 332	struct buffer_head *bh;
 333	int err = -ENOMEM;
 334	ino_t ino;
 335
 336	inode = new_inode(sb);
 337	if (unlikely(!inode))
 338		goto failed;
 339
 340	mapping_set_gfp_mask(inode->i_mapping,
 341			   mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 342
 343	root = NILFS_I(dir)->i_root;
 344	ii = NILFS_I(inode);
 345	ii->i_state = BIT(NILFS_I_NEW);
 346	ii->i_root = root;
 347
 348	err = nilfs_ifile_create_inode(root->ifile, &ino, &bh);
 349	if (unlikely(err))
 350		goto failed_ifile_create_inode;
 351	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
 352
 353	if (unlikely(ino < NILFS_USER_INO)) {
 354		nilfs_warn(sb,
 355			   "inode bitmap is inconsistent for reserved inodes");
 356		do {
 357			brelse(bh);
 358			err = nilfs_ifile_create_inode(root->ifile, &ino, &bh);
 359			if (unlikely(err))
 360				goto failed_ifile_create_inode;
 361		} while (ino < NILFS_USER_INO);
 362
 363		nilfs_info(sb, "repaired inode bitmap for reserved inodes");
 364	}
 365	ii->i_bh = bh;
 366
 367	atomic64_inc(&root->inodes_count);
 368	inode_init_owner(&nop_mnt_idmap, inode, dir, mode);
 369	inode->i_ino = ino;
 370	simple_inode_init_ts(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	if (inode->i_state & I_NEW)
 409		unlock_new_inode(inode);
 410	iput(inode);  /*
 411		       * raw_inode will be deleted through
 412		       * nilfs_evict_inode().
 413		       */
 414	goto failed;
 415
 416 failed_ifile_create_inode:
 417	make_bad_inode(inode);
 418	iput(inode);
 
 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_set_atime(inode, le64_to_cpu(raw_inode->i_mtime),
 454			le32_to_cpu(raw_inode->i_mtime_nsec));
 455	inode_set_ctime(inode, le64_to_cpu(raw_inode->i_ctime),
 456			le32_to_cpu(raw_inode->i_ctime_nsec));
 457	inode_set_mtime(inode, le64_to_cpu(raw_inode->i_mtime),
 458			le32_to_cpu(raw_inode->i_mtime_nsec));
 459	if (nilfs_is_metadata_file_inode(inode) && !S_ISREG(inode->i_mode))
 460		return -EIO; /* this inode is for metadata and corrupted */
 461	if (inode->i_nlink == 0)
 462		return -ESTALE; /* this inode is deleted */
 463
 464	inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 465	ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 466#if 0
 467	ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 468	ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 469		0 : le32_to_cpu(raw_inode->i_dir_acl);
 470#endif
 471	ii->i_dir_start_lookup = 0;
 472	inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 473
 474	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 475	    S_ISLNK(inode->i_mode)) {
 476		err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 477		if (err < 0)
 478			return err;
 479		set_bit(NILFS_I_BMAP, &ii->i_state);
 480		/* No lock is needed; iget() ensures it. */
 481	}
 482	return 0;
 483}
 484
 485static int __nilfs_read_inode(struct super_block *sb,
 486			      struct nilfs_root *root, unsigned long ino,
 487			      struct inode *inode)
 488{
 489	struct the_nilfs *nilfs = sb->s_fs_info;
 490	struct buffer_head *bh;
 491	struct nilfs_inode *raw_inode;
 492	int err;
 493
 494	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 495	err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
 496	if (unlikely(err))
 497		goto bad_inode;
 498
 499	raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
 500
 501	err = nilfs_read_inode_common(inode, raw_inode);
 502	if (err)
 503		goto failed_unmap;
 504
 505	if (S_ISREG(inode->i_mode)) {
 506		inode->i_op = &nilfs_file_inode_operations;
 507		inode->i_fop = &nilfs_file_operations;
 508		inode->i_mapping->a_ops = &nilfs_aops;
 509	} else if (S_ISDIR(inode->i_mode)) {
 510		inode->i_op = &nilfs_dir_inode_operations;
 511		inode->i_fop = &nilfs_dir_operations;
 512		inode->i_mapping->a_ops = &nilfs_aops;
 513	} else if (S_ISLNK(inode->i_mode)) {
 514		inode->i_op = &nilfs_symlink_inode_operations;
 515		inode_nohighmem(inode);
 516		inode->i_mapping->a_ops = &nilfs_aops;
 517	} else {
 518		inode->i_op = &nilfs_special_inode_operations;
 519		init_special_inode(
 520			inode, inode->i_mode,
 521			huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 522	}
 523	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 524	brelse(bh);
 525	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 526	nilfs_set_inode_flags(inode);
 527	mapping_set_gfp_mask(inode->i_mapping,
 528			   mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 529	return 0;
 530
 531 failed_unmap:
 532	nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 533	brelse(bh);
 534
 535 bad_inode:
 536	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 537	return err;
 538}
 539
 540static int nilfs_iget_test(struct inode *inode, void *opaque)
 541{
 542	struct nilfs_iget_args *args = opaque;
 543	struct nilfs_inode_info *ii;
 544
 545	if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
 546		return 0;
 547
 548	ii = NILFS_I(inode);
 549	if (test_bit(NILFS_I_BTNC, &ii->i_state)) {
 550		if (!args->for_btnc)
 551			return 0;
 552	} else if (args->for_btnc) {
 553		return 0;
 554	}
 555	if (test_bit(NILFS_I_SHADOW, &ii->i_state)) {
 556		if (!args->for_shadow)
 557			return 0;
 558	} else if (args->for_shadow) {
 559		return 0;
 560	}
 561
 562	if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
 563		return !args->for_gc;
 564
 565	return args->for_gc && args->cno == ii->i_cno;
 566}
 567
 568static int nilfs_iget_set(struct inode *inode, void *opaque)
 569{
 570	struct nilfs_iget_args *args = opaque;
 571
 572	inode->i_ino = args->ino;
 573	NILFS_I(inode)->i_cno = args->cno;
 574	NILFS_I(inode)->i_root = args->root;
 575	if (args->root && args->ino == NILFS_ROOT_INO)
 576		nilfs_get_root(args->root);
 577
 578	if (args->for_gc)
 579		NILFS_I(inode)->i_state = BIT(NILFS_I_GCINODE);
 580	if (args->for_btnc)
 581		NILFS_I(inode)->i_state |= BIT(NILFS_I_BTNC);
 582	if (args->for_shadow)
 583		NILFS_I(inode)->i_state |= BIT(NILFS_I_SHADOW);
 584	return 0;
 585}
 586
 587struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
 588			    unsigned long ino)
 589{
 590	struct nilfs_iget_args args = {
 591		.ino = ino, .root = root, .cno = 0, .for_gc = false,
 592		.for_btnc = false, .for_shadow = false
 593	};
 594
 595	return ilookup5(sb, ino, nilfs_iget_test, &args);
 596}
 597
 598struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
 599				unsigned long ino)
 600{
 601	struct nilfs_iget_args args = {
 602		.ino = ino, .root = root, .cno = 0, .for_gc = false,
 603		.for_btnc = false, .for_shadow = false
 604	};
 605
 606	return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 607}
 608
 609struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
 610			 unsigned long ino)
 611{
 612	struct inode *inode;
 613	int err;
 614
 615	inode = nilfs_iget_locked(sb, root, ino);
 616	if (unlikely(!inode))
 617		return ERR_PTR(-ENOMEM);
 618	if (!(inode->i_state & I_NEW))
 619		return inode;
 620
 621	err = __nilfs_read_inode(sb, root, ino, inode);
 622	if (unlikely(err)) {
 623		iget_failed(inode);
 624		return ERR_PTR(err);
 625	}
 626	unlock_new_inode(inode);
 627	return inode;
 628}
 629
 630struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
 631				__u64 cno)
 632{
 633	struct nilfs_iget_args args = {
 634		.ino = ino, .root = NULL, .cno = cno, .for_gc = true,
 635		.for_btnc = false, .for_shadow = false
 636	};
 637	struct inode *inode;
 638	int err;
 639
 640	inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 641	if (unlikely(!inode))
 642		return ERR_PTR(-ENOMEM);
 643	if (!(inode->i_state & I_NEW))
 644		return inode;
 645
 646	err = nilfs_init_gcinode(inode);
 647	if (unlikely(err)) {
 648		iget_failed(inode);
 649		return ERR_PTR(err);
 650	}
 651	unlock_new_inode(inode);
 652	return inode;
 653}
 654
 655/**
 656 * nilfs_attach_btree_node_cache - attach a B-tree node cache to the inode
 657 * @inode: inode object
 658 *
 659 * nilfs_attach_btree_node_cache() attaches a B-tree node cache to @inode,
 660 * or does nothing if the inode already has it.  This function allocates
 661 * an additional inode to maintain page cache of B-tree nodes one-on-one.
 662 *
 663 * Return Value: On success, 0 is returned. On errors, one of the following
 664 * negative error code is returned.
 665 *
 666 * %-ENOMEM - Insufficient memory available.
 667 */
 668int nilfs_attach_btree_node_cache(struct inode *inode)
 669{
 670	struct nilfs_inode_info *ii = NILFS_I(inode);
 671	struct inode *btnc_inode;
 672	struct nilfs_iget_args args;
 673
 674	if (ii->i_assoc_inode)
 675		return 0;
 676
 677	args.ino = inode->i_ino;
 678	args.root = ii->i_root;
 679	args.cno = ii->i_cno;
 680	args.for_gc = test_bit(NILFS_I_GCINODE, &ii->i_state) != 0;
 681	args.for_btnc = true;
 682	args.for_shadow = test_bit(NILFS_I_SHADOW, &ii->i_state) != 0;
 683
 684	btnc_inode = iget5_locked(inode->i_sb, inode->i_ino, nilfs_iget_test,
 685				  nilfs_iget_set, &args);
 686	if (unlikely(!btnc_inode))
 687		return -ENOMEM;
 688	if (btnc_inode->i_state & I_NEW) {
 689		nilfs_init_btnc_inode(btnc_inode);
 690		unlock_new_inode(btnc_inode);
 691	}
 692	NILFS_I(btnc_inode)->i_assoc_inode = inode;
 693	NILFS_I(btnc_inode)->i_bmap = ii->i_bmap;
 694	ii->i_assoc_inode = btnc_inode;
 695
 696	return 0;
 697}
 698
 699/**
 700 * nilfs_detach_btree_node_cache - detach the B-tree node cache from the inode
 701 * @inode: inode object
 702 *
 703 * nilfs_detach_btree_node_cache() detaches the B-tree node cache and its
 704 * holder inode bound to @inode, or does nothing if @inode doesn't have it.
 705 */
 706void nilfs_detach_btree_node_cache(struct inode *inode)
 707{
 708	struct nilfs_inode_info *ii = NILFS_I(inode);
 709	struct inode *btnc_inode = ii->i_assoc_inode;
 710
 711	if (btnc_inode) {
 712		NILFS_I(btnc_inode)->i_assoc_inode = NULL;
 713		ii->i_assoc_inode = NULL;
 714		iput(btnc_inode);
 715	}
 716}
 717
 718/**
 719 * nilfs_iget_for_shadow - obtain inode for shadow mapping
 720 * @inode: inode object that uses shadow mapping
 721 *
 722 * nilfs_iget_for_shadow() allocates a pair of inodes that holds page
 723 * caches for shadow mapping.  The page cache for data pages is set up
 724 * in one inode and the one for b-tree node pages is set up in the
 725 * other inode, which is attached to the former inode.
 726 *
 727 * Return Value: On success, a pointer to the inode for data pages is
 728 * returned. On errors, one of the following negative error code is returned
 729 * in a pointer type.
 730 *
 731 * %-ENOMEM - Insufficient memory available.
 732 */
 733struct inode *nilfs_iget_for_shadow(struct inode *inode)
 734{
 735	struct nilfs_iget_args args = {
 736		.ino = inode->i_ino, .root = NULL, .cno = 0, .for_gc = false,
 737		.for_btnc = false, .for_shadow = true
 738	};
 739	struct inode *s_inode;
 740	int err;
 741
 742	s_inode = iget5_locked(inode->i_sb, inode->i_ino, nilfs_iget_test,
 743			       nilfs_iget_set, &args);
 744	if (unlikely(!s_inode))
 745		return ERR_PTR(-ENOMEM);
 746	if (!(s_inode->i_state & I_NEW))
 747		return inode;
 748
 749	NILFS_I(s_inode)->i_flags = 0;
 750	memset(NILFS_I(s_inode)->i_bmap, 0, sizeof(struct nilfs_bmap));
 751	mapping_set_gfp_mask(s_inode->i_mapping, GFP_NOFS);
 752
 753	err = nilfs_attach_btree_node_cache(s_inode);
 754	if (unlikely(err)) {
 755		iget_failed(s_inode);
 756		return ERR_PTR(err);
 757	}
 758	unlock_new_inode(s_inode);
 759	return s_inode;
 760}
 761
 762void nilfs_write_inode_common(struct inode *inode,
 763			      struct nilfs_inode *raw_inode, int has_bmap)
 764{
 765	struct nilfs_inode_info *ii = NILFS_I(inode);
 766
 767	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 768	raw_inode->i_uid = cpu_to_le32(i_uid_read(inode));
 769	raw_inode->i_gid = cpu_to_le32(i_gid_read(inode));
 770	raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 771	raw_inode->i_size = cpu_to_le64(inode->i_size);
 772	raw_inode->i_ctime = cpu_to_le64(inode_get_ctime_sec(inode));
 773	raw_inode->i_mtime = cpu_to_le64(inode_get_mtime_sec(inode));
 774	raw_inode->i_ctime_nsec = cpu_to_le32(inode_get_ctime_nsec(inode));
 775	raw_inode->i_mtime_nsec = cpu_to_le32(inode_get_mtime_nsec(inode));
 776	raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 777
 778	raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 779	raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 780
 781	if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) {
 782		struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 783
 784		/* zero-fill unused portion in the case of super root block */
 785		raw_inode->i_xattr = 0;
 786		raw_inode->i_pad = 0;
 787		memset((void *)raw_inode + sizeof(*raw_inode), 0,
 788		       nilfs->ns_inode_size - sizeof(*raw_inode));
 789	}
 790
 791	if (has_bmap)
 792		nilfs_bmap_write(ii->i_bmap, raw_inode);
 793	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 794		raw_inode->i_device_code =
 795			cpu_to_le64(huge_encode_dev(inode->i_rdev));
 796	/*
 797	 * When extending inode, nilfs->ns_inode_size should be checked
 798	 * for substitutions of appended fields.
 799	 */
 800}
 801
 802void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh, int flags)
 803{
 804	ino_t ino = inode->i_ino;
 805	struct nilfs_inode_info *ii = NILFS_I(inode);
 806	struct inode *ifile = ii->i_root->ifile;
 807	struct nilfs_inode *raw_inode;
 808
 809	raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
 810
 811	if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 812		memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
 813	if (flags & I_DIRTY_DATASYNC)
 814		set_bit(NILFS_I_INODE_SYNC, &ii->i_state);
 815
 816	nilfs_write_inode_common(inode, raw_inode, 0);
 817		/*
 818		 * XXX: call with has_bmap = 0 is a workaround to avoid
 819		 * deadlock of bmap.  This delays update of i_bmap to just
 820		 * before writing.
 821		 */
 822
 823	nilfs_ifile_unmap_inode(ifile, ino, ibh);
 824}
 825
 826#define NILFS_MAX_TRUNCATE_BLOCKS	16384  /* 64MB for 4KB block */
 827
 828static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 829				unsigned long from)
 830{
 831	__u64 b;
 832	int ret;
 833
 834	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 835		return;
 836repeat:
 837	ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 838	if (ret == -ENOENT)
 839		return;
 840	else if (ret < 0)
 841		goto failed;
 842
 843	if (b < from)
 844		return;
 845
 846	b -= min_t(__u64, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 847	ret = nilfs_bmap_truncate(ii->i_bmap, b);
 848	nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 849	if (!ret || (ret == -ENOMEM &&
 850		     nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 851		goto repeat;
 852
 853failed:
 854	nilfs_warn(ii->vfs_inode.i_sb, "error %d truncating bmap (ino=%lu)",
 855		   ret, ii->vfs_inode.i_ino);
 
 856}
 857
 858void nilfs_truncate(struct inode *inode)
 859{
 860	unsigned long blkoff;
 861	unsigned int blocksize;
 862	struct nilfs_transaction_info ti;
 863	struct super_block *sb = inode->i_sb;
 864	struct nilfs_inode_info *ii = NILFS_I(inode);
 865
 866	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 867		return;
 868	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 869		return;
 870
 871	blocksize = sb->s_blocksize;
 872	blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 873	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 874
 875	block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 876
 877	nilfs_truncate_bmap(ii, blkoff);
 878
 879	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
 880	if (IS_SYNC(inode))
 881		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 882
 883	nilfs_mark_inode_dirty(inode);
 884	nilfs_set_file_dirty(inode, 0);
 885	nilfs_transaction_commit(sb);
 886	/*
 887	 * May construct a logical segment and may fail in sync mode.
 888	 * But truncate has no return value.
 889	 */
 890}
 891
 892static void nilfs_clear_inode(struct inode *inode)
 893{
 894	struct nilfs_inode_info *ii = NILFS_I(inode);
 
 895
 896	/*
 897	 * Free resources allocated in nilfs_read_inode(), here.
 898	 */
 899	BUG_ON(!list_empty(&ii->i_dirty));
 900	brelse(ii->i_bh);
 901	ii->i_bh = NULL;
 902
 903	if (nilfs_is_metadata_file_inode(inode))
 904		nilfs_mdt_clear(inode);
 905
 906	if (test_bit(NILFS_I_BMAP, &ii->i_state))
 907		nilfs_bmap_clear(ii->i_bmap);
 908
 909	if (!test_bit(NILFS_I_BTNC, &ii->i_state))
 910		nilfs_detach_btree_node_cache(inode);
 911
 912	if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
 913		nilfs_put_root(ii->i_root);
 914}
 915
 916void nilfs_evict_inode(struct inode *inode)
 917{
 918	struct nilfs_transaction_info ti;
 919	struct super_block *sb = inode->i_sb;
 920	struct nilfs_inode_info *ii = NILFS_I(inode);
 921	struct the_nilfs *nilfs;
 922	int ret;
 923
 924	if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
 925		truncate_inode_pages_final(&inode->i_data);
 926		clear_inode(inode);
 927		nilfs_clear_inode(inode);
 928		return;
 929	}
 930	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 931
 932	truncate_inode_pages_final(&inode->i_data);
 933
 934	nilfs = sb->s_fs_info;
 935	if (unlikely(sb_rdonly(sb) || !nilfs->ns_writer)) {
 936		/*
 937		 * If this inode is about to be disposed after the file system
 938		 * has been degraded to read-only due to file system corruption
 939		 * or after the writer has been detached, do not make any
 940		 * changes that cause writes, just clear it.
 941		 * Do this check after read-locking ns_segctor_sem by
 942		 * nilfs_transaction_begin() in order to avoid a race with
 943		 * the writer detach operation.
 944		 */
 945		clear_inode(inode);
 946		nilfs_clear_inode(inode);
 947		nilfs_transaction_abort(sb);
 948		return;
 949	}
 950
 951	/* TODO: some of the following operations may fail.  */
 952	nilfs_truncate_bmap(ii, 0);
 953	nilfs_mark_inode_dirty(inode);
 954	clear_inode(inode);
 955
 956	ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
 957	if (!ret)
 958		atomic64_dec(&ii->i_root->inodes_count);
 959
 960	nilfs_clear_inode(inode);
 961
 962	if (IS_SYNC(inode))
 963		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 964	nilfs_transaction_commit(sb);
 965	/*
 966	 * May construct a logical segment and may fail in sync mode.
 967	 * But delete_inode has no return value.
 968	 */
 969}
 970
 971int nilfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 972		  struct iattr *iattr)
 973{
 974	struct nilfs_transaction_info ti;
 975	struct inode *inode = d_inode(dentry);
 976	struct super_block *sb = inode->i_sb;
 977	int err;
 978
 979	err = setattr_prepare(&nop_mnt_idmap, dentry, iattr);
 980	if (err)
 981		return err;
 982
 983	err = nilfs_transaction_begin(sb, &ti, 0);
 984	if (unlikely(err))
 985		return err;
 986
 987	if ((iattr->ia_valid & ATTR_SIZE) &&
 988	    iattr->ia_size != i_size_read(inode)) {
 989		inode_dio_wait(inode);
 990		truncate_setsize(inode, iattr->ia_size);
 991		nilfs_truncate(inode);
 992	}
 993
 994	setattr_copy(&nop_mnt_idmap, inode, iattr);
 995	mark_inode_dirty(inode);
 996
 997	if (iattr->ia_valid & ATTR_MODE) {
 998		err = nilfs_acl_chmod(inode);
 999		if (unlikely(err))
1000			goto out_err;
1001	}
1002
1003	return nilfs_transaction_commit(sb);
1004
1005out_err:
1006	nilfs_transaction_abort(sb);
1007	return err;
1008}
1009
1010int nilfs_permission(struct mnt_idmap *idmap, struct inode *inode,
1011		     int mask)
1012{
1013	struct nilfs_root *root = NILFS_I(inode)->i_root;
1014
1015	if ((mask & MAY_WRITE) && root &&
1016	    root->cno != NILFS_CPTREE_CURRENT_CNO)
1017		return -EROFS; /* snapshot is not writable */
1018
1019	return generic_permission(&nop_mnt_idmap, inode, mask);
1020}
1021
1022int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
1023{
1024	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1025	struct nilfs_inode_info *ii = NILFS_I(inode);
1026	int err;
1027
1028	spin_lock(&nilfs->ns_inode_lock);
1029	if (ii->i_bh == NULL || unlikely(!buffer_uptodate(ii->i_bh))) {
1030		spin_unlock(&nilfs->ns_inode_lock);
1031		err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
1032						  inode->i_ino, pbh);
1033		if (unlikely(err))
1034			return err;
1035		spin_lock(&nilfs->ns_inode_lock);
1036		if (ii->i_bh == NULL)
1037			ii->i_bh = *pbh;
1038		else if (unlikely(!buffer_uptodate(ii->i_bh))) {
1039			__brelse(ii->i_bh);
1040			ii->i_bh = *pbh;
1041		} else {
1042			brelse(*pbh);
1043			*pbh = ii->i_bh;
1044		}
1045	} else
1046		*pbh = ii->i_bh;
1047
1048	get_bh(*pbh);
1049	spin_unlock(&nilfs->ns_inode_lock);
1050	return 0;
1051}
1052
1053int nilfs_inode_dirty(struct inode *inode)
1054{
1055	struct nilfs_inode_info *ii = NILFS_I(inode);
1056	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1057	int ret = 0;
1058
1059	if (!list_empty(&ii->i_dirty)) {
1060		spin_lock(&nilfs->ns_inode_lock);
1061		ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
1062			test_bit(NILFS_I_BUSY, &ii->i_state);
1063		spin_unlock(&nilfs->ns_inode_lock);
1064	}
1065	return ret;
1066}
1067
1068int nilfs_set_file_dirty(struct inode *inode, unsigned int nr_dirty)
1069{
1070	struct nilfs_inode_info *ii = NILFS_I(inode);
1071	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1072
1073	atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);
1074
1075	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
1076		return 0;
1077
1078	spin_lock(&nilfs->ns_inode_lock);
1079	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
1080	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
1081		/*
1082		 * Because this routine may race with nilfs_dispose_list(),
1083		 * we have to check NILFS_I_QUEUED here, too.
1084		 */
1085		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
1086			/*
1087			 * This will happen when somebody is freeing
1088			 * this inode.
1089			 */
1090			nilfs_warn(inode->i_sb,
1091				   "cannot set file dirty (ino=%lu): the file is being freed",
1092				   inode->i_ino);
1093			spin_unlock(&nilfs->ns_inode_lock);
1094			return -EINVAL; /*
1095					 * NILFS_I_DIRTY may remain for
1096					 * freeing inode.
1097					 */
1098		}
1099		list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
1100		set_bit(NILFS_I_QUEUED, &ii->i_state);
1101	}
1102	spin_unlock(&nilfs->ns_inode_lock);
1103	return 0;
1104}
1105
1106int __nilfs_mark_inode_dirty(struct inode *inode, int flags)
1107{
1108	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1109	struct buffer_head *ibh;
1110	int err;
1111
1112	/*
1113	 * Do not dirty inodes after the log writer has been detached
1114	 * and its nilfs_root struct has been freed.
1115	 */
1116	if (unlikely(nilfs_purging(nilfs)))
1117		return 0;
1118
1119	err = nilfs_load_inode_block(inode, &ibh);
1120	if (unlikely(err)) {
1121		nilfs_warn(inode->i_sb,
1122			   "cannot mark inode dirty (ino=%lu): error %d loading inode block",
1123			   inode->i_ino, err);
1124		return err;
1125	}
1126	nilfs_update_inode(inode, ibh, flags);
1127	mark_buffer_dirty(ibh);
1128	nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
1129	brelse(ibh);
1130	return 0;
1131}
1132
1133/**
1134 * nilfs_dirty_inode - reflect changes on given inode to an inode block.
1135 * @inode: inode of the file to be registered.
1136 * @flags: flags to determine the dirty state of the inode
1137 *
1138 * nilfs_dirty_inode() loads a inode block containing the specified
1139 * @inode and copies data from a nilfs_inode to a corresponding inode
1140 * entry in the inode block. This operation is excluded from the segment
1141 * construction. This function can be called both as a single operation
1142 * and as a part of indivisible file operations.
1143 */
1144void nilfs_dirty_inode(struct inode *inode, int flags)
1145{
1146	struct nilfs_transaction_info ti;
1147	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
1148
1149	if (is_bad_inode(inode)) {
1150		nilfs_warn(inode->i_sb,
1151			   "tried to mark bad_inode dirty. ignored.");
1152		dump_stack();
1153		return;
1154	}
1155	if (mdi) {
1156		nilfs_mdt_mark_dirty(inode);
1157		return;
1158	}
1159	nilfs_transaction_begin(inode->i_sb, &ti, 0);
1160	__nilfs_mark_inode_dirty(inode, flags);
1161	nilfs_transaction_commit(inode->i_sb); /* never fails */
1162}
1163
1164int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1165		 __u64 start, __u64 len)
1166{
1167	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
1168	__u64 logical = 0, phys = 0, size = 0;
1169	__u32 flags = 0;
1170	loff_t isize;
1171	sector_t blkoff, end_blkoff;
1172	sector_t delalloc_blkoff;
1173	unsigned long delalloc_blklen;
1174	unsigned int blkbits = inode->i_blkbits;
1175	int ret, n;
1176
1177	ret = fiemap_prep(inode, fieinfo, start, &len, 0);
1178	if (ret)
1179		return ret;
1180
1181	inode_lock(inode);
1182
1183	isize = i_size_read(inode);
1184
1185	blkoff = start >> blkbits;
1186	end_blkoff = (start + len - 1) >> blkbits;
1187
1188	delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
1189							&delalloc_blkoff);
1190
1191	do {
1192		__u64 blkphy;
1193		unsigned int maxblocks;
1194
1195		if (delalloc_blklen && blkoff == delalloc_blkoff) {
1196			if (size) {
1197				/* End of the current extent */
1198				ret = fiemap_fill_next_extent(
1199					fieinfo, logical, phys, size, flags);
1200				if (ret)
1201					break;
1202			}
1203			if (blkoff > end_blkoff)
1204				break;
1205
1206			flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
1207			logical = blkoff << blkbits;
1208			phys = 0;
1209			size = delalloc_blklen << blkbits;
1210
1211			blkoff = delalloc_blkoff + delalloc_blklen;
1212			delalloc_blklen = nilfs_find_uncommitted_extent(
1213				inode, blkoff, &delalloc_blkoff);
1214			continue;
1215		}
1216
1217		/*
1218		 * Limit the number of blocks that we look up so as
1219		 * not to get into the next delayed allocation extent.
1220		 */
1221		maxblocks = INT_MAX;
1222		if (delalloc_blklen)
1223			maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
1224					  maxblocks);
1225		blkphy = 0;
1226
1227		down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1228		n = nilfs_bmap_lookup_contig(
1229			NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
1230		up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1231
1232		if (n < 0) {
1233			int past_eof;
1234
1235			if (unlikely(n != -ENOENT))
1236				break; /* error */
1237
1238			/* HOLE */
1239			blkoff++;
1240			past_eof = ((blkoff << blkbits) >= isize);
1241
1242			if (size) {
1243				/* End of the current extent */
1244
1245				if (past_eof)
1246					flags |= FIEMAP_EXTENT_LAST;
1247
1248				ret = fiemap_fill_next_extent(
1249					fieinfo, logical, phys, size, flags);
1250				if (ret)
1251					break;
1252				size = 0;
1253			}
1254			if (blkoff > end_blkoff || past_eof)
1255				break;
1256		} else {
1257			if (size) {
1258				if (phys && blkphy << blkbits == phys + size) {
1259					/* The current extent goes on */
1260					size += n << blkbits;
1261				} else {
1262					/* Terminate the current extent */
1263					ret = fiemap_fill_next_extent(
1264						fieinfo, logical, phys, size,
1265						flags);
1266					if (ret || blkoff > end_blkoff)
1267						break;
1268
1269					/* Start another extent */
1270					flags = FIEMAP_EXTENT_MERGED;
1271					logical = blkoff << blkbits;
1272					phys = blkphy << blkbits;
1273					size = n << blkbits;
1274				}
1275			} else {
1276				/* Start a new extent */
1277				flags = FIEMAP_EXTENT_MERGED;
1278				logical = blkoff << blkbits;
1279				phys = blkphy << blkbits;
1280				size = n << blkbits;
1281			}
1282			blkoff += n;
1283		}
1284		cond_resched();
1285	} while (true);
1286
1287	/* If ret is 1 then we just hit the end of the extent array */
1288	if (ret == 1)
1289		ret = 0;
1290
1291	inode_unlock(inode);
1292	return ret;
1293}
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}