[mirror_ubuntu-jammy-kernel.git] / fs / f2fs / dir.c

/*
 * fs/f2fs/dir.c
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/fs.h>
#include <linux/f2fs_fs.h>
#include "f2fs.h"
#include "node.h"
#include "acl.h"
#include "xattr.h"

static unsigned long dir_blocks(struct inode *inode)
{
	return ((unsigned long long) (i_size_read(inode) + PAGE_CACHE_SIZE - 1))
							>> PAGE_CACHE_SHIFT;
}

static unsigned int dir_buckets(unsigned int level, int dir_level)
{
	if (level < MAX_DIR_HASH_DEPTH / 2)
		return 1 << (level + dir_level);
	else
		return 1 << ((MAX_DIR_HASH_DEPTH / 2 + dir_level) - 1);
}

static unsigned int bucket_blocks(unsigned int level)
{
	if (level < MAX_DIR_HASH_DEPTH / 2)
		return 2;
	else
		return 4;
}

static unsigned char f2fs_filetype_table[F2FS_FT_MAX] = {
	[F2FS_FT_UNKNOWN]	= DT_UNKNOWN,
	[F2FS_FT_REG_FILE]	= DT_REG,
	[F2FS_FT_DIR]		= DT_DIR,
	[F2FS_FT_CHRDEV]	= DT_CHR,
	[F2FS_FT_BLKDEV]	= DT_BLK,
	[F2FS_FT_FIFO]		= DT_FIFO,
	[F2FS_FT_SOCK]		= DT_SOCK,
	[F2FS_FT_SYMLINK]	= DT_LNK,
};

#define S_SHIFT 12
static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = {
	[S_IFREG >> S_SHIFT]	= F2FS_FT_REG_FILE,
	[S_IFDIR >> S_SHIFT]	= F2FS_FT_DIR,
	[S_IFCHR >> S_SHIFT]	= F2FS_FT_CHRDEV,
	[S_IFBLK >> S_SHIFT]	= F2FS_FT_BLKDEV,
	[S_IFIFO >> S_SHIFT]	= F2FS_FT_FIFO,
	[S_IFSOCK >> S_SHIFT]	= F2FS_FT_SOCK,
	[S_IFLNK >> S_SHIFT]	= F2FS_FT_SYMLINK,
};

static void set_de_type(struct f2fs_dir_entry *de, struct inode *inode)
{
	umode_t mode = inode->i_mode;
	de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
}

static unsigned long dir_block_index(unsigned int level,
				int dir_level, unsigned int idx)
{
	unsigned long i;
	unsigned long bidx = 0;

	for (i = 0; i < level; i++)
		bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
	bidx += idx * bucket_blocks(level);
	return bidx;
}

static bool early_match_name(const char *name, size_t namelen,
			f2fs_hash_t namehash, struct f2fs_dir_entry *de)
{
	if (le16_to_cpu(de->name_len) != namelen)
		return false;

	if (de->hash_code != namehash)
		return false;

	return true;
}

static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
			const char *name, size_t namelen, int *max_slots,
			f2fs_hash_t namehash, struct page **res_page)
{
	struct f2fs_dir_entry *de;
	unsigned long bit_pos = 0;
	struct f2fs_dentry_block *dentry_blk = kmap(dentry_page);
	int max_len = 0;

	while (bit_pos < NR_DENTRY_IN_BLOCK) {
		de = &dentry_blk->dentry[bit_pos];
		if (!test_bit_le(bit_pos, &dentry_blk->dentry_bitmap)) {
			if (bit_pos == 0)
				max_len = 1;
			else if (!test_bit_le(bit_pos - 1, &dentry_blk->dentry_bitmap))
				max_len++;
			bit_pos++;
			continue;
		}
		if (early_match_name(name, namelen, namehash, de)) {
			if (!memcmp(dentry_blk->filename[bit_pos],
							name, namelen)) {
				*res_page = dentry_page;
				goto found;
			}
		}
		if (max_len > *max_slots) {
			*max_slots = max_len;
			max_len = 0;
		}
		bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
	}

	de = NULL;
	kunmap(dentry_page);
found:
	if (max_len > *max_slots)
		*max_slots = max_len;
	return de;
}

static struct f2fs_dir_entry *find_in_level(struct inode *dir,
		unsigned int level, const char *name, size_t namelen,
			f2fs_hash_t namehash, struct page **res_page)
{
	int s = GET_DENTRY_SLOTS(namelen);
	unsigned int nbucket, nblock;
	unsigned int bidx, end_block;
	struct page *dentry_page;
	struct f2fs_dir_entry *de = NULL;
	bool room = false;
	int max_slots = 0;

	f2fs_bug_on(level > MAX_DIR_HASH_DEPTH);

	nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
	nblock = bucket_blocks(level);

	bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
					le32_to_cpu(namehash) % nbucket);
	end_block = bidx + nblock;

	for (; bidx < end_block; bidx++) {
		/* no need to allocate new dentry pages to all the indices */
		dentry_page = find_data_page(dir, bidx, true);
		if (IS_ERR(dentry_page)) {
			room = true;
			continue;
		}

		de = find_in_block(dentry_page, name, namelen,
					&max_slots, namehash, res_page);
		if (de)
			break;

		if (max_slots >= s)
			room = true;
		f2fs_put_page(dentry_page, 0);
	}

	if (!de && room && F2FS_I(dir)->chash != namehash) {
		F2FS_I(dir)->chash = namehash;
		F2FS_I(dir)->clevel = level;
	}

	return de;
}

/*
 * Find an entry in the specified directory with the wanted name.
 * It returns the page where the entry was found (as a parameter - res_page),
 * and the entry itself. Page is returned mapped and unlocked.
 * Entry is guaranteed to be valid.
 */
struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
			struct qstr *child, struct page **res_page)
{
	const char *name = child->name;
	size_t namelen = child->len;
	unsigned long npages = dir_blocks(dir);
	struct f2fs_dir_entry *de = NULL;
	f2fs_hash_t name_hash;
	unsigned int max_depth;
	unsigned int level;

	if (npages == 0)
		return NULL;

	*res_page = NULL;

	name_hash = f2fs_dentry_hash(name, namelen);
	max_depth = F2FS_I(dir)->i_current_depth;

	for (level = 0; level < max_depth; level++) {
		de = find_in_level(dir, level, name,
				namelen, name_hash, res_page);
		if (de)
			break;
	}
	if (!de && F2FS_I(dir)->chash != name_hash) {
		F2FS_I(dir)->chash = name_hash;
		F2FS_I(dir)->clevel = level - 1;
	}
	return de;
}

struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
{
	struct page *page;
	struct f2fs_dir_entry *de;
	struct f2fs_dentry_block *dentry_blk;

	page = get_lock_data_page(dir, 0);
	if (IS_ERR(page))
		return NULL;

	dentry_blk = kmap(page);
	de = &dentry_blk->dentry[1];
	*p = page;
	unlock_page(page);
	return de;
}

ino_t f2fs_inode_by_name(struct inode *dir, struct qstr *qstr)
{
	ino_t res = 0;
	struct f2fs_dir_entry *de;
	struct page *page;

	de = f2fs_find_entry(dir, qstr, &page);
	if (de) {
		res = le32_to_cpu(de->ino);
		kunmap(page);
		f2fs_put_page(page, 0);
	}

	return res;
}

void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
		struct page *page, struct inode *inode)
{
	lock_page(page);
	wait_on_page_writeback(page);
	de->ino = cpu_to_le32(inode->i_ino);
	set_de_type(de, inode);
	kunmap(page);
	set_page_dirty(page);
	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	mark_inode_dirty(dir);

	f2fs_put_page(page, 1);
}

static void init_dent_inode(const struct qstr *name, struct page *ipage)
{
	struct f2fs_inode *ri;

	/* copy name info. to this inode page */
	ri = F2FS_INODE(ipage);
	ri->i_namelen = cpu_to_le32(name->len);
	memcpy(ri->i_name, name->name, name->len);
	set_page_dirty(ipage);
}

int update_dent_inode(struct inode *inode, const struct qstr *name)
{
	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
	struct page *page;

	page = get_node_page(sbi, inode->i_ino);
	if (IS_ERR(page))
		return PTR_ERR(page);

	init_dent_inode(name, page);
	f2fs_put_page(page, 1);

	return 0;
}

static int make_empty_dir(struct inode *inode,
		struct inode *parent, struct page *page)
{
	struct page *dentry_page;
	struct f2fs_dentry_block *dentry_blk;
	struct f2fs_dir_entry *de;
	void *kaddr;

	dentry_page = get_new_data_page(inode, page, 0, true);
	if (IS_ERR(dentry_page))
		return PTR_ERR(dentry_page);

	kaddr = kmap_atomic(dentry_page);
	dentry_blk = (struct f2fs_dentry_block *)kaddr;

	de = &dentry_blk->dentry[0];
	de->name_len = cpu_to_le16(1);
	de->hash_code = 0;
	de->ino = cpu_to_le32(inode->i_ino);
	memcpy(dentry_blk->filename[0], ".", 1);
	set_de_type(de, inode);

	de = &dentry_blk->dentry[1];
	de->hash_code = 0;
	de->name_len = cpu_to_le16(2);
	de->ino = cpu_to_le32(parent->i_ino);
	memcpy(dentry_blk->filename[1], "..", 2);
	set_de_type(de, inode);

	test_and_set_bit_le(0, &dentry_blk->dentry_bitmap);
	test_and_set_bit_le(1, &dentry_blk->dentry_bitmap);
	kunmap_atomic(kaddr);

	set_page_dirty(dentry_page);
	f2fs_put_page(dentry_page, 1);
	return 0;
}

static struct page *init_inode_metadata(struct inode *inode,
		struct inode *dir, const struct qstr *name)
{
	struct page *page;
	int err;

	if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
		page = new_inode_page(inode, name);
		if (IS_ERR(page))
			return page;

		if (S_ISDIR(inode->i_mode)) {
			err = make_empty_dir(inode, dir, page);
			if (err)
				goto error;
		}

		err = f2fs_init_acl(inode, dir, page);
		if (err)
			goto put_error;

		err = f2fs_init_security(inode, dir, name, page);
		if (err)
			goto put_error;

		wait_on_page_writeback(page);
	} else {
		page = get_node_page(F2FS_SB(dir->i_sb), inode->i_ino);
		if (IS_ERR(page))
			return page;

		wait_on_page_writeback(page);
		set_cold_node(inode, page);
	}

	init_dent_inode(name, page);

	/*
	 * This file should be checkpointed during fsync.
	 * We lost i_pino from now on.
	 */
	if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) {
		file_lost_pino(inode);
		inc_nlink(inode);
	}
	return page;

put_error:
	f2fs_put_page(page, 1);
	/* once the failed inode becomes a bad inode, i_mode is S_IFREG */
	truncate_inode_pages(&inode->i_data, 0);
	truncate_blocks(inode, 0);
	remove_dirty_dir_inode(inode);
error:
	remove_inode_page(inode);
	return ERR_PTR(err);
}

static void update_parent_metadata(struct inode *dir, struct inode *inode,
						unsigned int current_depth)
{
	if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
		if (S_ISDIR(inode->i_mode)) {
			inc_nlink(dir);
			set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
		}
		clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
	}
	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	mark_inode_dirty(dir);

	if (F2FS_I(dir)->i_current_depth != current_depth) {
		F2FS_I(dir)->i_current_depth = current_depth;
		set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
	}

	if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK))
		clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
}

static int room_for_filename(struct f2fs_dentry_block *dentry_blk, int slots)
{
	int bit_start = 0;
	int zero_start, zero_end;
next:
	zero_start = find_next_zero_bit_le(&dentry_blk->dentry_bitmap,
						NR_DENTRY_IN_BLOCK,
						bit_start);
	if (zero_start >= NR_DENTRY_IN_BLOCK)
		return NR_DENTRY_IN_BLOCK;

	zero_end = find_next_bit_le(&dentry_blk->dentry_bitmap,
						NR_DENTRY_IN_BLOCK,
						zero_start);
	if (zero_end - zero_start >= slots)
		return zero_start;

	bit_start = zero_end + 1;

	if (zero_end + 1 >= NR_DENTRY_IN_BLOCK)
		return NR_DENTRY_IN_BLOCK;
	goto next;
}

/*
 * Caller should grab and release a rwsem by calling f2fs_lock_op() and
 * f2fs_unlock_op().
 */
int __f2fs_add_link(struct inode *dir, const struct qstr *name,
						struct inode *inode)
{
	unsigned int bit_pos;
	unsigned int level;
	unsigned int current_depth;
	unsigned long bidx, block;
	f2fs_hash_t dentry_hash;
	struct f2fs_dir_entry *de;
	unsigned int nbucket, nblock;
	size_t namelen = name->len;
	struct page *dentry_page = NULL;
	struct f2fs_dentry_block *dentry_blk = NULL;
	int slots = GET_DENTRY_SLOTS(namelen);
	struct page *page;
	int err = 0;
	int i;

	dentry_hash = f2fs_dentry_hash(name->name, name->len);
	level = 0;
	current_depth = F2FS_I(dir)->i_current_depth;
	if (F2FS_I(dir)->chash == dentry_hash) {
		level = F2FS_I(dir)->clevel;
		F2FS_I(dir)->chash = 0;
	}

start:
	if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
		return -ENOSPC;

	/* Increase the depth, if required */
	if (level == current_depth)
		++current_depth;

	nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
	nblock = bucket_blocks(level);

	bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
				(le32_to_cpu(dentry_hash) % nbucket));

	for (block = bidx; block <= (bidx + nblock - 1); block++) {
		dentry_page = get_new_data_page(dir, NULL, block, true);
		if (IS_ERR(dentry_page))
			return PTR_ERR(dentry_page);

		dentry_blk = kmap(dentry_page);
		bit_pos = room_for_filename(dentry_blk, slots);
		if (bit_pos < NR_DENTRY_IN_BLOCK)
			goto add_dentry;

		kunmap(dentry_page);
		f2fs_put_page(dentry_page, 1);
	}

	/* Move to next level to find the empty slot for new dentry */
	++level;
	goto start;
add_dentry:
	wait_on_page_writeback(dentry_page);

	page = init_inode_metadata(inode, dir, name);
	if (IS_ERR(page)) {
		err = PTR_ERR(page);
		goto fail;
	}
	de = &dentry_blk->dentry[bit_pos];
	de->hash_code = dentry_hash;
	de->name_len = cpu_to_le16(namelen);
	memcpy(dentry_blk->filename[bit_pos], name->name, name->len);
	de->ino = cpu_to_le32(inode->i_ino);
	set_de_type(de, inode);
	for (i = 0; i < slots; i++)
		test_and_set_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
	set_page_dirty(dentry_page);

	/* we don't need to mark_inode_dirty now */
	F2FS_I(inode)->i_pino = dir->i_ino;
	update_inode(inode, page);
	f2fs_put_page(page, 1);

	update_parent_metadata(dir, inode, current_depth);
fail:
	if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
		update_inode_page(dir);
		clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
	}
	kunmap(dentry_page);
	f2fs_put_page(dentry_page, 1);
	return err;
}

/*
 * It only removes the dentry from the dentry page,corresponding name
 * entry in name page does not need to be touched during deletion.
 */
void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
						struct inode *inode)
{
	struct	f2fs_dentry_block *dentry_blk;
	unsigned int bit_pos;
	struct address_space *mapping = page->mapping;
	struct inode *dir = mapping->host;
	int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
	void *kaddr = page_address(page);
	int i;

	lock_page(page);
	wait_on_page_writeback(page);

	dentry_blk = (struct f2fs_dentry_block *)kaddr;
	bit_pos = dentry - (struct f2fs_dir_entry *)dentry_blk->dentry;
	for (i = 0; i < slots; i++)
		test_and_clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);

	/* Let's check and deallocate this dentry page */
	bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
			NR_DENTRY_IN_BLOCK,
			0);
	kunmap(page); /* kunmap - pair of f2fs_find_entry */
	set_page_dirty(page);

	dir->i_ctime = dir->i_mtime = CURRENT_TIME;

	if (inode) {
		struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);

		if (S_ISDIR(inode->i_mode)) {
			drop_nlink(dir);
			update_inode_page(dir);
		}
		inode->i_ctime = CURRENT_TIME;
		drop_nlink(inode);
		if (S_ISDIR(inode->i_mode)) {
			drop_nlink(inode);
			i_size_write(inode, 0);
		}
		update_inode_page(inode);

		if (inode->i_nlink == 0)
			add_orphan_inode(sbi, inode->i_ino);
		else
			release_orphan_inode(sbi);
	}

	if (bit_pos == NR_DENTRY_IN_BLOCK) {
		truncate_hole(dir, page->index, page->index + 1);
		clear_page_dirty_for_io(page);
		ClearPageUptodate(page);
		inode_dec_dirty_dents(dir);
	}
	f2fs_put_page(page, 1);
}

bool f2fs_empty_dir(struct inode *dir)
{
	unsigned long bidx;
	struct page *dentry_page;
	unsigned int bit_pos;
	struct	f2fs_dentry_block *dentry_blk;
	unsigned long nblock = dir_blocks(dir);

	for (bidx = 0; bidx < nblock; bidx++) {
		void *kaddr;
		dentry_page = get_lock_data_page(dir, bidx);
		if (IS_ERR(dentry_page)) {
			if (PTR_ERR(dentry_page) == -ENOENT)
				continue;
			else
				return false;
		}

		kaddr = kmap_atomic(dentry_page);
		dentry_blk = (struct f2fs_dentry_block *)kaddr;
		if (bidx == 0)
			bit_pos = 2;
		else
			bit_pos = 0;
		bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
						NR_DENTRY_IN_BLOCK,
						bit_pos);
		kunmap_atomic(kaddr);

		f2fs_put_page(dentry_page, 1);

		if (bit_pos < NR_DENTRY_IN_BLOCK)
			return false;
	}
	return true;
}

static int f2fs_readdir(struct file *file, struct dir_context *ctx)
{
	struct inode *inode = file_inode(file);
	unsigned long npages = dir_blocks(inode);
	unsigned int bit_pos = 0;
	struct f2fs_dentry_block *dentry_blk = NULL;
	struct f2fs_dir_entry *de = NULL;
	struct page *dentry_page = NULL;
	unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
	unsigned char d_type = DT_UNKNOWN;

	bit_pos = ((unsigned long)ctx->pos % NR_DENTRY_IN_BLOCK);

	for (; n < npages; n++) {
		dentry_page = get_lock_data_page(inode, n);
		if (IS_ERR(dentry_page))
			continue;

		dentry_blk = kmap(dentry_page);
		while (bit_pos < NR_DENTRY_IN_BLOCK) {
			bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
							NR_DENTRY_IN_BLOCK,
							bit_pos);
			if (bit_pos >= NR_DENTRY_IN_BLOCK)
				break;

			de = &dentry_blk->dentry[bit_pos];
			if (de->file_type < F2FS_FT_MAX)
				d_type = f2fs_filetype_table[de->file_type];
			else
				d_type = DT_UNKNOWN;
			if (!dir_emit(ctx,
					dentry_blk->filename[bit_pos],
					le16_to_cpu(de->name_len),
					le32_to_cpu(de->ino), d_type))
				goto stop;

			bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
			ctx->pos = n * NR_DENTRY_IN_BLOCK + bit_pos;
		}
		bit_pos = 0;
		ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
		kunmap(dentry_page);
		f2fs_put_page(dentry_page, 1);
		dentry_page = NULL;
	}
stop:
	if (dentry_page && !IS_ERR(dentry_page)) {
		kunmap(dentry_page);
		f2fs_put_page(dentry_page, 1);
	}

	return 0;
}

const struct file_operations f2fs_dir_operations = {
	.llseek		= generic_file_llseek,
	.read		= generic_read_dir,
	.iterate	= f2fs_readdir,
	.fsync		= f2fs_sync_file,
	.unlocked_ioctl	= f2fs_ioctl,
};
Commit	Line	Data
0a8165d7	1	/*
6b4ea016 JK	2	* fs/f2fs/dir.c
	3	*
	4	* Copyright (c) 2012 Samsung Electronics Co., Ltd.
	5	* http://www.samsung.com/
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11	#include <linux/fs.h>
	12	#include <linux/f2fs_fs.h>
	13	#include "f2fs.h"
398b1ac5	14	#include "node.h"
6b4ea016	15	#include "acl.h"
8ae8f162	16	#include "xattr.h"
6b4ea016 JK	17
	18	static unsigned long dir_blocks(struct inode *inode)
	19	{
	20	return ((unsigned long long) (i_size_read(inode) + PAGE_CACHE_SIZE - 1))
	21	>> PAGE_CACHE_SHIFT;
	22	}
	23
38431545	24	static unsigned int dir_buckets(unsigned int level, int dir_level)
6b4ea016 JK	25	{
6b4ea016 JK	26	if (level < MAX_DIR_HASH_DEPTH / 2)
38431545	27	return 1 << (level + dir_level);
6b4ea016	28	else
38431545	29	return 1 << ((MAX_DIR_HASH_DEPTH / 2 + dir_level) - 1);
6b4ea016 JK	30	}
	31
	32	static unsigned int bucket_blocks(unsigned int level)
	33	{
	34	if (level < MAX_DIR_HASH_DEPTH / 2)
	35	return 2;
	36	else
	37	return 4;
	38	}
	39
	40	static unsigned char f2fs_filetype_table[F2FS_FT_MAX] = {
	41	[F2FS_FT_UNKNOWN] = DT_UNKNOWN,
	42	[F2FS_FT_REG_FILE] = DT_REG,
	43	[F2FS_FT_DIR] = DT_DIR,
	44	[F2FS_FT_CHRDEV] = DT_CHR,
	45	[F2FS_FT_BLKDEV] = DT_BLK,
	46	[F2FS_FT_FIFO] = DT_FIFO,
	47	[F2FS_FT_SOCK] = DT_SOCK,
	48	[F2FS_FT_SYMLINK] = DT_LNK,
	49	};
	50
	51	#define S_SHIFT 12
	52	static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = {
	53	[S_IFREG >> S_SHIFT] = F2FS_FT_REG_FILE,
	54	[S_IFDIR >> S_SHIFT] = F2FS_FT_DIR,
	55	[S_IFCHR >> S_SHIFT] = F2FS_FT_CHRDEV,
	56	[S_IFBLK >> S_SHIFT] = F2FS_FT_BLKDEV,
	57	[S_IFIFO >> S_SHIFT] = F2FS_FT_FIFO,
	58	[S_IFSOCK >> S_SHIFT] = F2FS_FT_SOCK,
	59	[S_IFLNK >> S_SHIFT] = F2FS_FT_SYMLINK,
	60	};
	61
	62	static void set_de_type(struct f2fs_dir_entry de, struct inode inode)
	63	{
0ecc833b	64	umode_t mode = inode->i_mode;
6b4ea016 JK	65	de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
	66	}
	67
38431545 JK	68	static unsigned long dir_block_index(unsigned int level,
38431545 JK	69	int dir_level, unsigned int idx)
6b4ea016 JK	70	{
	71	unsigned long i;
	72	unsigned long bidx = 0;
	73
	74	for (i = 0; i < level; i++)
38431545	75	bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
6b4ea016 JK	76	bidx += idx * bucket_blocks(level);
	77	return bidx;
	78	}
	79
9836b8b9	80	static bool early_match_name(const char *name, size_t namelen,
6b4ea016 JK	81	f2fs_hash_t namehash, struct f2fs_dir_entry *de)
	82	{
	83	if (le16_to_cpu(de->name_len) != namelen)
	84	return false;
	85
25ca923b	86	if (de->hash_code != namehash)
6b4ea016 JK	87	return false;
	88
	89	return true;
	90	}
	91
	92	static struct f2fs_dir_entry find_in_block(struct page dentry_page,
9836b8b9	93	const char name, size_t namelen, int max_slots,
6b4ea016 JK	94	f2fs_hash_t namehash, struct page **res_page)
	95	{
	96	struct f2fs_dir_entry *de;
5d0c6671	97	unsigned long bit_pos = 0;
6b4ea016	98	struct f2fs_dentry_block *dentry_blk = kmap(dentry_page);
5d0c6671	99	int max_len = 0;
6b4ea016	100
6b4ea016 JK	101	while (bit_pos < NR_DENTRY_IN_BLOCK) {
6b4ea016 JK	102	de = &dentry_blk->dentry[bit_pos];
5d0c6671 JK	103	if (!test_bit_le(bit_pos, &dentry_blk->dentry_bitmap)) {
	104	if (bit_pos == 0)
	105	max_len = 1;
	106	else if (!test_bit_le(bit_pos - 1, &dentry_blk->dentry_bitmap))
	107	max_len++;
	108	bit_pos++;
	109	continue;
	110	}
6b4ea016 JK	111	if (early_match_name(name, namelen, namehash, de)) {
	112	if (!memcmp(dentry_blk->filename[bit_pos],
	113	name, namelen)) {
	114	*res_page = dentry_page;
	115	goto found;
	116	}
	117	}
5d0c6671 JK	118	if (max_len > *max_slots) {
	119	*max_slots = max_len;
	120	max_len = 0;
	121	}
	122	bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
6b4ea016 JK	123	}
	124
	125	de = NULL;
	126	kunmap(dentry_page);
	127	found:
5d0c6671 JK	128	if (max_len > *max_slots)
5d0c6671 JK	129	*max_slots = max_len;
6b4ea016 JK	130	return de;
	131	}
	132
	133	static struct f2fs_dir_entry find_in_level(struct inode dir,
9836b8b9	134	unsigned int level, const char *name, size_t namelen,
6b4ea016 JK	135	f2fs_hash_t namehash, struct page **res_page)
6b4ea016 JK	136	{
457d08ee	137	int s = GET_DENTRY_SLOTS(namelen);
6b4ea016 JK	138	unsigned int nbucket, nblock;
	139	unsigned int bidx, end_block;
	140	struct page *dentry_page;
	141	struct f2fs_dir_entry *de = NULL;
	142	bool room = false;
	143	int max_slots = 0;
	144
5d56b671	145	f2fs_bug_on(level > MAX_DIR_HASH_DEPTH);
6b4ea016	146
38431545	147	nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
6b4ea016 JK	148	nblock = bucket_blocks(level);
6b4ea016 JK	149
38431545 JK	150	bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
38431545 JK	151	le32_to_cpu(namehash) % nbucket);
6b4ea016 JK	152	end_block = bidx + nblock;
	153
	154	for (; bidx < end_block; bidx++) {
	155	/* no need to allocate new dentry pages to all the indices */
c718379b	156	dentry_page = find_data_page(dir, bidx, true);
6b4ea016 JK	157	if (IS_ERR(dentry_page)) {
	158	room = true;
	159	continue;
	160	}
	161
	162	de = find_in_block(dentry_page, name, namelen,
	163	&max_slots, namehash, res_page);
	164	if (de)
	165	break;
	166
	167	if (max_slots >= s)
	168	room = true;
	169	f2fs_put_page(dentry_page, 0);
	170	}
	171
	172	if (!de && room && F2FS_I(dir)->chash != namehash) {
	173	F2FS_I(dir)->chash = namehash;
	174	F2FS_I(dir)->clevel = level;
	175	}
	176
	177	return de;
	178	}
	179
	180	/*
	181	* Find an entry in the specified directory with the wanted name.
	182	* It returns the page where the entry was found (as a parameter - res_page),
	183	* and the entry itself. Page is returned mapped and unlocked.
	184	* Entry is guaranteed to be valid.
	185	*/
	186	struct f2fs_dir_entry f2fs_find_entry(struct inode dir,
	187	struct qstr child, struct page *res_page)
	188	{
	189	const char *name = child->name;
9836b8b9	190	size_t namelen = child->len;
6b4ea016 JK	191	unsigned long npages = dir_blocks(dir);
	192	struct f2fs_dir_entry *de = NULL;
	193	f2fs_hash_t name_hash;
	194	unsigned int max_depth;
	195	unsigned int level;
	196
	197	if (npages == 0)
	198	return NULL;
	199
	200	*res_page = NULL;
	201
	202	name_hash = f2fs_dentry_hash(name, namelen);
	203	max_depth = F2FS_I(dir)->i_current_depth;
	204
	205	for (level = 0; level < max_depth; level++) {
	206	de = find_in_level(dir, level, name,
	207	namelen, name_hash, res_page);
	208	if (de)
	209	break;
	210	}
	211	if (!de && F2FS_I(dir)->chash != name_hash) {
	212	F2FS_I(dir)->chash = name_hash;
	213	F2FS_I(dir)->clevel = level - 1;
	214	}
	215	return de;
	216	}
	217
	218	struct f2fs_dir_entry f2fs_parent_dir(struct inode dir, struct page **p)
	219	{
4777f86b NJ	220	struct page *page;
	221	struct f2fs_dir_entry *de;
	222	struct f2fs_dentry_block *dentry_blk;
6b4ea016 JK	223
	224	page = get_lock_data_page(dir, 0);
	225	if (IS_ERR(page))
	226	return NULL;
	227
	228	dentry_blk = kmap(page);
	229	de = &dentry_blk->dentry[1];
	230	*p = page;
	231	unlock_page(page);
	232	return de;
	233	}
	234
	235	ino_t f2fs_inode_by_name(struct inode dir, struct qstr qstr)
	236	{
	237	ino_t res = 0;
	238	struct f2fs_dir_entry *de;
	239	struct page *page;
	240
	241	de = f2fs_find_entry(dir, qstr, &page);
	242	if (de) {
	243	res = le32_to_cpu(de->ino);
	244	kunmap(page);
	245	f2fs_put_page(page, 0);
	246	}
	247
	248	return res;
	249	}
	250
	251	void f2fs_set_link(struct inode dir, struct f2fs_dir_entry de,
	252	struct page page, struct inode inode)
	253	{
6b4ea016 JK	254	lock_page(page);
	255	wait_on_page_writeback(page);
	256	de->ino = cpu_to_le32(inode->i_ino);
	257	set_de_type(de, inode);
	258	kunmap(page);
	259	set_page_dirty(page);
	260	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
	261	mark_inode_dirty(dir);
6666e6aa	262
6b4ea016	263	f2fs_put_page(page, 1);
6b4ea016 JK	264	}
6b4ea016 JK	265
44a83ff6	266	static void init_dent_inode(const struct qstr name, struct page ipage)
6b4ea016	267	{
58bfaf44	268	struct f2fs_inode *ri;
6b4ea016	269
53dc9a67	270	/* copy name info. to this inode page */
58bfaf44 JK	271	ri = F2FS_INODE(ipage);
	272	ri->i_namelen = cpu_to_le32(name->len);
	273	memcpy(ri->i_name, name->name, name->len);
6b4ea016 JK	274	set_page_dirty(ipage);
	275	}
	276
1cd14caf JK	277	int update_dent_inode(struct inode inode, const struct qstr name)
	278	{
	279	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
	280	struct page *page;
	281
	282	page = get_node_page(sbi, inode->i_ino);
	283	if (IS_ERR(page))
	284	return PTR_ERR(page);
	285
	286	init_dent_inode(name, page);
	287	f2fs_put_page(page, 1);
	288
	289	return 0;
	290	}
	291
44a83ff6 JK	292	static int make_empty_dir(struct inode *inode,
44a83ff6 JK	293	struct inode parent, struct page page)
39936837 JK	294	{
	295	struct page *dentry_page;
	296	struct f2fs_dentry_block *dentry_blk;
	297	struct f2fs_dir_entry *de;
	298	void *kaddr;
	299
44a83ff6	300	dentry_page = get_new_data_page(inode, page, 0, true);
39936837 JK	301	if (IS_ERR(dentry_page))
	302	return PTR_ERR(dentry_page);
	303
	304	kaddr = kmap_atomic(dentry_page);
	305	dentry_blk = (struct f2fs_dentry_block *)kaddr;
	306
	307	de = &dentry_blk->dentry[0];
	308	de->name_len = cpu_to_le16(1);
	309	de->hash_code = 0;
	310	de->ino = cpu_to_le32(inode->i_ino);
	311	memcpy(dentry_blk->filename[0], ".", 1);
	312	set_de_type(de, inode);
	313
	314	de = &dentry_blk->dentry[1];
	315	de->hash_code = 0;
	316	de->name_len = cpu_to_le16(2);
	317	de->ino = cpu_to_le32(parent->i_ino);
	318	memcpy(dentry_blk->filename[1], "..", 2);
	319	set_de_type(de, inode);
	320
	321	test_and_set_bit_le(0, &dentry_blk->dentry_bitmap);
	322	test_and_set_bit_le(1, &dentry_blk->dentry_bitmap);
	323	kunmap_atomic(kaddr);
	324
	325	set_page_dirty(dentry_page);
	326	f2fs_put_page(dentry_page, 1);
	327	return 0;
	328	}
	329
44a83ff6	330	static struct page init_inode_metadata(struct inode inode,
69f24eac	331	struct inode dir, const struct qstr name)
6b4ea016	332	{
44a83ff6 JK	333	struct page *page;
	334	int err;
	335
6b4ea016	336	if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
44a83ff6 JK	337	page = new_inode_page(inode, name);
	338	if (IS_ERR(page))
	339	return page;
6b4ea016 JK	340
6b4ea016 JK	341	if (S_ISDIR(inode->i_mode)) {
44a83ff6 JK	342	err = make_empty_dir(inode, dir, page);
	343	if (err)
	344	goto error;
6b4ea016 JK	345	}
6b4ea016 JK	346
2ed2d5b3	347	err = f2fs_init_acl(inode, dir, page);
44a83ff6	348	if (err)
a8865372	349	goto put_error;
44a83ff6	350
8ae8f162 JK	351	err = f2fs_init_security(inode, dir, name, page);
8ae8f162 JK	352	if (err)
a8865372	353	goto put_error;
8ae8f162	354
44a83ff6	355	wait_on_page_writeback(page);
6b4ea016	356	} else {
44a83ff6 JK	357	page = get_node_page(F2FS_SB(dir->i_sb), inode->i_ino);
	358	if (IS_ERR(page))
	359	return page;
	360
	361	wait_on_page_writeback(page);
	362	set_cold_node(inode, page);
6b4ea016	363	}
44a83ff6 JK	364
	365	init_dent_inode(name, page);
	366
83d5d6f6 JK	367	/*
	368	* This file should be checkpointed during fsync.
	369	* We lost i_pino from now on.
	370	*/
6b4ea016	371	if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) {
354a3399	372	file_lost_pino(inode);
6b4ea016	373	inc_nlink(inode);
6b4ea016	374	}
44a83ff6 JK	375	return page;
44a83ff6 JK	376
a8865372	377	put_error:
44a83ff6	378	f2fs_put_page(page, 1);
bd859c65 JK	379	/* once the failed inode becomes a bad inode, i_mode is S_IFREG */
	380	truncate_inode_pages(&inode->i_data, 0);
	381	truncate_blocks(inode, 0);
	382	remove_dirty_dir_inode(inode);
a8865372	383	error:
44a83ff6 JK	384	remove_inode_page(inode);
44a83ff6 JK	385	return ERR_PTR(err);
6b4ea016 JK	386	}
	387
	388	static void update_parent_metadata(struct inode dir, struct inode inode,
	389	unsigned int current_depth)
	390	{
6b4ea016 JK	391	if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
	392	if (S_ISDIR(inode->i_mode)) {
	393	inc_nlink(dir);
699489bb	394	set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
6b4ea016 JK	395	}
	396	clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
	397	}
	398	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
a18ff063 JK	399	mark_inode_dirty(dir);
a18ff063 JK	400
6b4ea016 JK	401	if (F2FS_I(dir)->i_current_depth != current_depth) {
6b4ea016 JK	402	F2FS_I(dir)->i_current_depth = current_depth;
699489bb	403	set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
6b4ea016 JK	404	}
6b4ea016 JK	405
6b4ea016 JK	406	if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK))
	407	clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
	408	}
	409
	410	static int room_for_filename(struct f2fs_dentry_block *dentry_blk, int slots)
	411	{
	412	int bit_start = 0;
	413	int zero_start, zero_end;
	414	next:
	415	zero_start = find_next_zero_bit_le(&dentry_blk->dentry_bitmap,
	416	NR_DENTRY_IN_BLOCK,
	417	bit_start);
	418	if (zero_start >= NR_DENTRY_IN_BLOCK)
	419	return NR_DENTRY_IN_BLOCK;
	420
	421	zero_end = find_next_bit_le(&dentry_blk->dentry_bitmap,
	422	NR_DENTRY_IN_BLOCK,
	423	zero_start);
	424	if (zero_end - zero_start >= slots)
	425	return zero_start;
	426
	427	bit_start = zero_end + 1;
	428
	429	if (zero_end + 1 >= NR_DENTRY_IN_BLOCK)
	430	return NR_DENTRY_IN_BLOCK;
	431	goto next;
	432	}
	433
39936837	434	/*
4f4124d0 CY	435	* Caller should grab and release a rwsem by calling f2fs_lock_op() and
4f4124d0 CY	436	* f2fs_unlock_op().
39936837	437	*/
6c311ec6 CF	438	int __f2fs_add_link(struct inode dir, const struct qstr name,
6c311ec6 CF	439	struct inode *inode)
6b4ea016 JK	440	{
	441	unsigned int bit_pos;
	442	unsigned int level;
	443	unsigned int current_depth;
	444	unsigned long bidx, block;
	445	f2fs_hash_t dentry_hash;
	446	struct f2fs_dir_entry *de;
	447	unsigned int nbucket, nblock;
b7f7a5e0	448	size_t namelen = name->len;
6b4ea016 JK	449	struct page *dentry_page = NULL;
6b4ea016 JK	450	struct f2fs_dentry_block *dentry_blk = NULL;
457d08ee	451	int slots = GET_DENTRY_SLOTS(namelen);
44a83ff6	452	struct page *page;
6b4ea016 JK	453	int err = 0;
	454	int i;
	455
b7f7a5e0	456	dentry_hash = f2fs_dentry_hash(name->name, name->len);
6b4ea016 JK	457	level = 0;
	458	current_depth = F2FS_I(dir)->i_current_depth;
	459	if (F2FS_I(dir)->chash == dentry_hash) {
	460	level = F2FS_I(dir)->clevel;
	461	F2FS_I(dir)->chash = 0;
	462	}
	463
	464	start:
cfb271d4	465	if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
6b4ea016 JK	466	return -ENOSPC;
	467
	468	/* Increase the depth, if required */
	469	if (level == current_depth)
	470	++current_depth;
	471
38431545	472	nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
6b4ea016 JK	473	nblock = bucket_blocks(level);
6b4ea016 JK	474
38431545 JK	475	bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
38431545 JK	476	(le32_to_cpu(dentry_hash) % nbucket));
6b4ea016 JK	477
6b4ea016 JK	478	for (block = bidx; block <= (bidx + nblock - 1); block++) {
64aa7ed9	479	dentry_page = get_new_data_page(dir, NULL, block, true);
39936837	480	if (IS_ERR(dentry_page))
6b4ea016	481	return PTR_ERR(dentry_page);
6b4ea016 JK	482
	483	dentry_blk = kmap(dentry_page);
	484	bit_pos = room_for_filename(dentry_blk, slots);
	485	if (bit_pos < NR_DENTRY_IN_BLOCK)
	486	goto add_dentry;
	487
	488	kunmap(dentry_page);
	489	f2fs_put_page(dentry_page, 1);
6b4ea016 JK	490	}
	491
	492	/* Move to next level to find the empty slot for new dentry */
	493	++level;
	494	goto start;
	495	add_dentry:
6b4ea016 JK	496	wait_on_page_writeback(dentry_page);
6b4ea016 JK	497
44a83ff6 JK	498	page = init_inode_metadata(inode, dir, name);
	499	if (IS_ERR(page)) {
	500	err = PTR_ERR(page);
	501	goto fail;
	502	}
6b4ea016	503	de = &dentry_blk->dentry[bit_pos];
25ca923b	504	de->hash_code = dentry_hash;
6b4ea016	505	de->name_len = cpu_to_le16(namelen);
b7f7a5e0	506	memcpy(dentry_blk->filename[bit_pos], name->name, name->len);
6b4ea016 JK	507	de->ino = cpu_to_le32(inode->i_ino);
	508	set_de_type(de, inode);
	509	for (i = 0; i < slots; i++)
	510	test_and_set_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
	511	set_page_dirty(dentry_page);
6666e6aa	512
44a83ff6	513	/* we don't need to mark_inode_dirty now */
6666e6aa	514	F2FS_I(inode)->i_pino = dir->i_ino;
44a83ff6 JK	515	update_inode(inode, page);
	516	f2fs_put_page(page, 1);
	517
	518	update_parent_metadata(dir, inode, current_depth);
6b4ea016	519	fail:
924a2ddb JK	520	if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) {
	521	update_inode_page(dir);
	522	clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
	523	}
6b4ea016 JK	524	kunmap(dentry_page);
6b4ea016 JK	525	f2fs_put_page(dentry_page, 1);
6b4ea016 JK	526	return err;
	527	}
	528
0a8165d7	529	/*
6b4ea016 JK	530	* It only removes the dentry from the dentry page,corresponding name
	531	* entry in name page does not need to be touched during deletion.
	532	*/
	533	void f2fs_delete_entry(struct f2fs_dir_entry dentry, struct page page,
	534	struct inode *inode)
	535	{
	536	struct f2fs_dentry_block *dentry_blk;
	537	unsigned int bit_pos;
	538	struct address_space *mapping = page->mapping;
	539	struct inode *dir = mapping->host;
457d08ee	540	int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
6b4ea016 JK	541	void *kaddr = page_address(page);
	542	int i;
	543
6b4ea016 JK	544	lock_page(page);
	545	wait_on_page_writeback(page);
	546
	547	dentry_blk = (struct f2fs_dentry_block *)kaddr;
	548	bit_pos = dentry - (struct f2fs_dir_entry *)dentry_blk->dentry;
	549	for (i = 0; i < slots; i++)
	550	test_and_clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
	551
	552	/* Let's check and deallocate this dentry page */
	553	bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
	554	NR_DENTRY_IN_BLOCK,
	555	0);
	556	kunmap(page); /* kunmap - pair of f2fs_find_entry */
	557	set_page_dirty(page);
	558
	559	dir->i_ctime = dir->i_mtime = CURRENT_TIME;
	560
6b4ea016	561	if (inode) {
1fe54f9d JK	562	struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
1fe54f9d JK	563
e8dae604 JK	564	if (S_ISDIR(inode->i_mode)) {
	565	drop_nlink(dir);
	566	update_inode_page(dir);
	567	}
16379987	568	inode->i_ctime = CURRENT_TIME;
6b4ea016 JK	569	drop_nlink(inode);
	570	if (S_ISDIR(inode->i_mode)) {
	571	drop_nlink(inode);
	572	i_size_write(inode, 0);
	573	}
39936837 JK	574	update_inode_page(inode);
39936837 JK	575
6b4ea016 JK	576	if (inode->i_nlink == 0)
6b4ea016 JK	577	add_orphan_inode(sbi, inode->i_ino);
cbd56e7d JK	578	else
cbd56e7d JK	579	release_orphan_inode(sbi);
6b4ea016 JK	580	}
	581
	582	if (bit_pos == NR_DENTRY_IN_BLOCK) {
6b4ea016 JK	583	truncate_hole(dir, page->index, page->index + 1);
	584	clear_page_dirty_for_io(page);
	585	ClearPageUptodate(page);
6b4ea016	586	inode_dec_dirty_dents(dir);
6b4ea016	587	}
508198be	588	f2fs_put_page(page, 1);
6b4ea016 JK	589	}
	590
	591	bool f2fs_empty_dir(struct inode *dir)
	592	{
	593	unsigned long bidx;
	594	struct page *dentry_page;
	595	unsigned int bit_pos;
	596	struct f2fs_dentry_block *dentry_blk;
	597	unsigned long nblock = dir_blocks(dir);
	598
	599	for (bidx = 0; bidx < nblock; bidx++) {
	600	void *kaddr;
	601	dentry_page = get_lock_data_page(dir, bidx);
	602	if (IS_ERR(dentry_page)) {
	603	if (PTR_ERR(dentry_page) == -ENOENT)
	604	continue;
	605	else
	606	return false;
	607	}
	608
	609	kaddr = kmap_atomic(dentry_page);
	610	dentry_blk = (struct f2fs_dentry_block *)kaddr;
	611	if (bidx == 0)
	612	bit_pos = 2;
	613	else
	614	bit_pos = 0;
	615	bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
	616	NR_DENTRY_IN_BLOCK,
	617	bit_pos);
	618	kunmap_atomic(kaddr);
	619
	620	f2fs_put_page(dentry_page, 1);
	621
	622	if (bit_pos < NR_DENTRY_IN_BLOCK)
	623	return false;
	624	}
	625	return true;
	626	}
	627
6f7f231e	628	static int f2fs_readdir(struct file file, struct dir_context ctx)
6b4ea016	629	{
496ad9aa	630	struct inode *inode = file_inode(file);
6b4ea016	631	unsigned long npages = dir_blocks(inode);
99b072bb	632	unsigned int bit_pos = 0;
6b4ea016 JK	633	struct f2fs_dentry_block *dentry_blk = NULL;
	634	struct f2fs_dir_entry *de = NULL;
	635	struct page *dentry_page = NULL;
6f7f231e	636	unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
6b4ea016	637	unsigned char d_type = DT_UNKNOWN;
6b4ea016	638
6f7f231e	639	bit_pos = ((unsigned long)ctx->pos % NR_DENTRY_IN_BLOCK);
6b4ea016	640
6c311ec6	641	for (; n < npages; n++) {
6b4ea016 JK	642	dentry_page = get_lock_data_page(inode, n);
	643	if (IS_ERR(dentry_page))
	644	continue;
	645
6b4ea016 JK	646	dentry_blk = kmap(dentry_page);
6b4ea016 JK	647	while (bit_pos < NR_DENTRY_IN_BLOCK) {
6b4ea016 JK	648	bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
	649	NR_DENTRY_IN_BLOCK,
	650	bit_pos);
	651	if (bit_pos >= NR_DENTRY_IN_BLOCK)
	652	break;
	653
	654	de = &dentry_blk->dentry[bit_pos];
6f7f231e AV	655	if (de->file_type < F2FS_FT_MAX)
	656	d_type = f2fs_filetype_table[de->file_type];
	657	else
	658	d_type = DT_UNKNOWN;
	659	if (!dir_emit(ctx,
99b072bb JK	660	dentry_blk->filename[bit_pos],
	661	le16_to_cpu(de->name_len),
	662	le32_to_cpu(de->ino), d_type))
	663	goto stop;
	664
	665	bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
	666	ctx->pos = n * NR_DENTRY_IN_BLOCK + bit_pos;
6b4ea016 JK	667	}
6b4ea016 JK	668	bit_pos = 0;
6f7f231e	669	ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
6b4ea016 JK	670	kunmap(dentry_page);
	671	f2fs_put_page(dentry_page, 1);
	672	dentry_page = NULL;
	673	}
99b072bb	674	stop:
6b4ea016 JK	675	if (dentry_page && !IS_ERR(dentry_page)) {
	676	kunmap(dentry_page);
	677	f2fs_put_page(dentry_page, 1);
	678	}
	679
	680	return 0;
	681	}
	682
	683	const struct file_operations f2fs_dir_operations = {
	684	.llseek = generic_file_llseek,
	685	.read = generic_read_dir,
6f7f231e	686	.iterate = f2fs_readdir,
6b4ea016 JK	687	.fsync = f2fs_sync_file,
	688	.unlocked_ioctl = f2fs_ioctl,
	689	};