[linux-block.git] / fs / exfat / inode.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
 */

#include <linux/init.h>
#include <linux/buffer_head.h>
#include <linux/mpage.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/time.h>
#include <linux/writeback.h>
#include <linux/uio.h>
#include <linux/random.h>
#include <linux/iversion.h>

#include "exfat_raw.h"
#include "exfat_fs.h"

static int __exfat_write_inode(struct inode *inode, int sync)
{
	int ret = -EIO;
	unsigned long long on_disk_size;
	struct exfat_dentry *ep, *ep2;
	struct exfat_entry_set_cache *es = NULL;
	struct super_block *sb = inode->i_sb;
	struct exfat_sb_info *sbi = EXFAT_SB(sb);
	struct exfat_inode_info *ei = EXFAT_I(inode);
	bool is_dir = (ei->type == TYPE_DIR) ? true : false;

	if (inode->i_ino == EXFAT_ROOT_INO)
		return 0;

	/*
	 * If the indode is already unlinked, there is no need for updating it.
	 */
	if (ei->dir.dir == DIR_DELETED)
		return 0;

	if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)
		return 0;

	exfat_set_vol_flags(sb, VOL_DIRTY);

	/* get the directory entry of given file or directory */
	es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES,
		&ep);
	if (!es)
		return -EIO;
	ep2 = ep + 1;

	ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode));

	/* set FILE_INFO structure using the acquired struct exfat_dentry */
	exfat_set_entry_time(sbi, &ei->i_crtime,
			&ep->dentry.file.create_tz,
			&ep->dentry.file.create_time,
			&ep->dentry.file.create_date,
			&ep->dentry.file.create_time_ms);
	exfat_set_entry_time(sbi, &inode->i_mtime,
			&ep->dentry.file.modify_tz,
			&ep->dentry.file.modify_time,
			&ep->dentry.file.modify_date,
			&ep->dentry.file.modify_time_ms);
	exfat_set_entry_time(sbi, &inode->i_atime,
			&ep->dentry.file.access_tz,
			&ep->dentry.file.access_time,
			&ep->dentry.file.access_date,
			NULL);

	/* File size should be zero if there is no cluster allocated */
	on_disk_size = i_size_read(inode);

	if (ei->start_clu == EXFAT_EOF_CLUSTER)
		on_disk_size = 0;

	ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size);
	ep2->dentry.stream.size = ep2->dentry.stream.valid_size;

	ret = exfat_update_dir_chksum_with_entry_set(sb, es, sync);
	kfree(es);
	return ret;
}

int exfat_write_inode(struct inode *inode, struct writeback_control *wbc)
{
	int ret;

	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
	ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);

	return ret;
}

void exfat_sync_inode(struct inode *inode)
{
	lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
	__exfat_write_inode(inode, 1);
}

/*
 * Input: inode, (logical) clu_offset, target allocation area
 * Output: errcode, cluster number
 * *clu = (~0), if it's unable to allocate a new cluster
 */
static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
		unsigned int *clu, int create)
{
	int ret, modified = false;
	unsigned int last_clu;
	struct exfat_chain new_clu;
	struct exfat_dentry *ep;
	struct exfat_entry_set_cache *es = NULL;
	struct super_block *sb = inode->i_sb;
	struct exfat_sb_info *sbi = EXFAT_SB(sb);
	struct exfat_inode_info *ei = EXFAT_I(inode);
	unsigned int local_clu_offset = clu_offset;
	unsigned int num_to_be_allocated = 0, num_clusters = 0;

	ei->rwoffset = EXFAT_CLU_TO_B(clu_offset, sbi);

	if (EXFAT_I(inode)->i_size_ondisk > 0)
		num_clusters =
			EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk,
			sbi);

	if (clu_offset >= num_clusters)
		num_to_be_allocated = clu_offset - num_clusters + 1;

	if (!create && (num_to_be_allocated > 0)) {
		*clu = EXFAT_EOF_CLUSTER;
		return 0;
	}

	*clu = last_clu = ei->start_clu;

	if (ei->flags == ALLOC_NO_FAT_CHAIN) {
		if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
			last_clu += clu_offset - 1;

			if (clu_offset == num_clusters)
				*clu = EXFAT_EOF_CLUSTER;
			else
				*clu += clu_offset;
		}
	} else if (ei->type == TYPE_FILE) {
		unsigned int fclus = 0;
		int err = exfat_get_cluster(inode, clu_offset,
				&fclus, clu, &last_clu, 1);
		if (err)
			return -EIO;

		clu_offset -= fclus;
	} else {
		/* hint information */
		if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
		    ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
			clu_offset -= ei->hint_bmap.off;
			/* hint_bmap.clu should be valid */
			WARN_ON(ei->hint_bmap.clu < 2);
			*clu = ei->hint_bmap.clu;
		}

		while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
			last_clu = *clu;
			if (exfat_get_next_cluster(sb, clu))
				return -EIO;
			clu_offset--;
		}
	}

	if (*clu == EXFAT_EOF_CLUSTER) {
		exfat_set_vol_flags(sb, VOL_DIRTY);

		new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
				EXFAT_EOF_CLUSTER : last_clu + 1;
		new_clu.size = 0;
		new_clu.flags = ei->flags;

		/* allocate a cluster */
		if (num_to_be_allocated < 1) {
			/* Broken FAT (i_sze > allocated FAT) */
			exfat_fs_error(sb, "broken FAT chain.");
			return -EIO;
		}

		ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu);
		if (ret)
			return ret;

		if (new_clu.dir == EXFAT_EOF_CLUSTER ||
		    new_clu.dir == EXFAT_FREE_CLUSTER) {
			exfat_fs_error(sb,
				"bogus cluster new allocated (last_clu : %u, new_clu : %u)",
				last_clu, new_clu.dir);
			return -EIO;
		}

		/* append to the FAT chain */
		if (last_clu == EXFAT_EOF_CLUSTER) {
			if (new_clu.flags == ALLOC_FAT_CHAIN)
				ei->flags = ALLOC_FAT_CHAIN;
			ei->start_clu = new_clu.dir;
			modified = true;
		} else {
			if (new_clu.flags != ei->flags) {
				/* no-fat-chain bit is disabled,
				 * so fat-chain should be synced with
				 * alloc-bitmap
				 */
				exfat_chain_cont_cluster(sb, ei->start_clu,
					num_clusters);
				ei->flags = ALLOC_FAT_CHAIN;
				modified = true;
			}
			if (new_clu.flags == ALLOC_FAT_CHAIN)
				if (exfat_ent_set(sb, last_clu, new_clu.dir))
					return -EIO;
		}

		num_clusters += num_to_be_allocated;
		*clu = new_clu.dir;

		if (ei->dir.dir != DIR_DELETED) {
			es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry,
				ES_ALL_ENTRIES, &ep);
			if (!es)
				return -EIO;
			/* get stream entry */
			ep++;

			/* update directory entry */
			if (modified) {
				if (ep->dentry.stream.flags != ei->flags)
					ep->dentry.stream.flags = ei->flags;

				if (le32_to_cpu(ep->dentry.stream.start_clu) !=
						ei->start_clu)
					ep->dentry.stream.start_clu =
						cpu_to_le32(ei->start_clu);

				ep->dentry.stream.valid_size =
					cpu_to_le64(i_size_read(inode));
				ep->dentry.stream.size =
					ep->dentry.stream.valid_size;
			}

			if (exfat_update_dir_chksum_with_entry_set(sb, es,
			    inode_needs_sync(inode)))
				return -EIO;
			kfree(es);

		} /* end of if != DIR_DELETED */

		inode->i_blocks +=
			num_to_be_allocated << sbi->sect_per_clus_bits;

		/*
		 * Move *clu pointer along FAT chains (hole care) because the
		 * caller of this function expect *clu to be the last cluster.
		 * This only works when num_to_be_allocated >= 2,
		 * *clu = (the first cluster of the allocated chain) =>
		 * (the last cluster of ...)
		 */
		if (ei->flags == ALLOC_NO_FAT_CHAIN) {
			*clu += num_to_be_allocated - 1;
		} else {
			while (num_to_be_allocated > 1) {
				if (exfat_get_next_cluster(sb, clu))
					return -EIO;
				num_to_be_allocated--;
			}
		}

	}

	/* hint information */
	ei->hint_bmap.off = local_clu_offset;
	ei->hint_bmap.clu = *clu;

	return 0;
}

static int exfat_map_new_buffer(struct exfat_inode_info *ei,
		struct buffer_head *bh, loff_t pos)
{
	if (buffer_delay(bh) && pos > ei->i_size_aligned)
		return -EIO;
	set_buffer_new(bh);

	/*
	 * Adjust i_size_aligned if i_size_ondisk is bigger than it.
	 */
	if (ei->i_size_ondisk > ei->i_size_aligned)
		ei->i_size_aligned = ei->i_size_ondisk;
	return 0;
}

static int exfat_get_block(struct inode *inode, sector_t iblock,
		struct buffer_head *bh_result, int create)
{
	struct exfat_inode_info *ei = EXFAT_I(inode);
	struct super_block *sb = inode->i_sb;
	struct exfat_sb_info *sbi = EXFAT_SB(sb);
	unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
	int err = 0;
	unsigned long mapped_blocks = 0;
	unsigned int cluster, sec_offset;
	sector_t last_block;
	sector_t phys = 0;
	loff_t pos;

	mutex_lock(&sbi->s_lock);
	last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
	if (iblock >= last_block && !create)
		goto done;

	/* Is this block already allocated? */
	err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
			&cluster, create);
	if (err) {
		if (err != -ENOSPC)
			exfat_fs_error_ratelimit(sb,
				"failed to bmap (inode : %p iblock : %llu, err : %d)",
				inode, (unsigned long long)iblock, err);
		goto unlock_ret;
	}

	if (cluster == EXFAT_EOF_CLUSTER)
		goto done;

	/* sector offset in cluster */
	sec_offset = iblock & (sbi->sect_per_clus - 1);

	phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
	mapped_blocks = sbi->sect_per_clus - sec_offset;
	max_blocks = min(mapped_blocks, max_blocks);

	/* Treat newly added block / cluster */
	if (iblock < last_block)
		create = 0;

	if (create || buffer_delay(bh_result)) {
		pos = EXFAT_BLK_TO_B((iblock + 1), sb);
		if (ei->i_size_ondisk < pos)
			ei->i_size_ondisk = pos;
	}

	if (create) {
		err = exfat_map_new_buffer(ei, bh_result, pos);
		if (err) {
			exfat_fs_error(sb,
					"requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
					pos, ei->i_size_aligned);
			goto unlock_ret;
		}
	}

	if (buffer_delay(bh_result))
		clear_buffer_delay(bh_result);
	map_bh(bh_result, sb, phys);
done:
	bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
unlock_ret:
	mutex_unlock(&sbi->s_lock);
	return err;
}

static int exfat_readpage(struct file *file, struct page *page)
{
	return mpage_readpage(page, exfat_get_block);
}

static int exfat_readpages(struct file *file, struct address_space *mapping,
		struct list_head *pages, unsigned int nr_pages)
{
	return mpage_readpages(mapping, pages, nr_pages, exfat_get_block);
}

static int exfat_writepage(struct page *page, struct writeback_control *wbc)
{
	return block_write_full_page(page, exfat_get_block, wbc);
}

static int exfat_writepages(struct address_space *mapping,
		struct writeback_control *wbc)
{
	return mpage_writepages(mapping, wbc, exfat_get_block);
}

static void exfat_write_failed(struct address_space *mapping, loff_t to)
{
	struct inode *inode = mapping->host;

	if (to > i_size_read(inode)) {
		truncate_pagecache(inode, i_size_read(inode));
		exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned);
	}
}

static int exfat_write_begin(struct file *file, struct address_space *mapping,
		loff_t pos, unsigned int len, unsigned int flags,
		struct page **pagep, void **fsdata)
{
	int ret;

	*pagep = NULL;
	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
			       exfat_get_block,
			       &EXFAT_I(mapping->host)->i_size_ondisk);

	if (ret < 0)
		exfat_write_failed(mapping, pos+len);

	return ret;
}

static int exfat_write_end(struct file *file, struct address_space *mapping,
		loff_t pos, unsigned int len, unsigned int copied,
		struct page *pagep, void *fsdata)
{
	struct inode *inode = mapping->host;
	struct exfat_inode_info *ei = EXFAT_I(inode);
	int err;

	err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);

	if (EXFAT_I(inode)->i_size_aligned < i_size_read(inode)) {
		exfat_fs_error(inode->i_sb,
			"invalid size(size(%llu) > aligned(%llu)\n",
			i_size_read(inode), EXFAT_I(inode)->i_size_aligned);
		return -EIO;
	}

	if (err < len)
		exfat_write_failed(mapping, pos+len);

	if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
		inode->i_mtime = inode->i_ctime = current_time(inode);
		ei->attr |= ATTR_ARCHIVE;
		mark_inode_dirty(inode);
	}

	return err;
}

static ssize_t exfat_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
{
	struct address_space *mapping = iocb->ki_filp->f_mapping;
	struct inode *inode = mapping->host;
	loff_t size = iocb->ki_pos + iov_iter_count(iter);
	int rw = iov_iter_rw(iter);
	ssize_t ret;

	if (rw == WRITE) {
		/*
		 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
		 * so we need to update the ->i_size_aligned to block boundary.
		 *
		 * But we must fill the remaining area or hole by nul for
		 * updating ->i_size_aligned
		 *
		 * Return 0, and fallback to normal buffered write.
		 */
		if (EXFAT_I(inode)->i_size_aligned < size)
			return 0;
	}

	/*
	 * Need to use the DIO_LOCKING for avoiding the race
	 * condition of exfat_get_block() and ->truncate().
	 */
	ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
	if (ret < 0 && (rw & WRITE))
		exfat_write_failed(mapping, size);
	return ret;
}

static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
{
	sector_t blocknr;

	/* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
	down_read(&EXFAT_I(mapping->host)->truncate_lock);
	blocknr = generic_block_bmap(mapping, block, exfat_get_block);
	up_read(&EXFAT_I(mapping->host)->truncate_lock);
	return blocknr;
}

/*
 * exfat_block_truncate_page() zeroes out a mapping from file offset `from'
 * up to the end of the block which corresponds to `from'.
 * This is required during truncate to physically zeroout the tail end
 * of that block so it doesn't yield old data if the file is later grown.
 * Also, avoid causing failure from fsx for cases of "data past EOF"
 */
int exfat_block_truncate_page(struct inode *inode, loff_t from)
{
	return block_truncate_page(inode->i_mapping, from, exfat_get_block);
}

static const struct address_space_operations exfat_aops = {
	.readpage	= exfat_readpage,
	.readpages	= exfat_readpages,
	.writepage	= exfat_writepage,
	.writepages	= exfat_writepages,
	.write_begin	= exfat_write_begin,
	.write_end	= exfat_write_end,
	.direct_IO	= exfat_direct_IO,
	.bmap		= exfat_aop_bmap
};

static inline unsigned long exfat_hash(loff_t i_pos)
{
	return hash_32(i_pos, EXFAT_HASH_BITS);
}

void exfat_hash_inode(struct inode *inode, loff_t i_pos)
{
	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
	struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);

	spin_lock(&sbi->inode_hash_lock);
	EXFAT_I(inode)->i_pos = i_pos;
	hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
	spin_unlock(&sbi->inode_hash_lock);
}

void exfat_unhash_inode(struct inode *inode)
{
	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);

	spin_lock(&sbi->inode_hash_lock);
	hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
	EXFAT_I(inode)->i_pos = 0;
	spin_unlock(&sbi->inode_hash_lock);
}

struct inode *exfat_iget(struct super_block *sb, loff_t i_pos)
{
	struct exfat_sb_info *sbi = EXFAT_SB(sb);
	struct exfat_inode_info *info;
	struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
	struct inode *inode = NULL;

	spin_lock(&sbi->inode_hash_lock);
	hlist_for_each_entry(info, head, i_hash_fat) {
		WARN_ON(info->vfs_inode.i_sb != sb);

		if (i_pos != info->i_pos)
			continue;
		inode = igrab(&info->vfs_inode);
		if (inode)
			break;
	}
	spin_unlock(&sbi->inode_hash_lock);
	return inode;
}

/* doesn't deal with root inode */
static int exfat_fill_inode(struct inode *inode, struct exfat_dir_entry *info)
{
	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
	struct exfat_inode_info *ei = EXFAT_I(inode);
	loff_t size = info->size;

	memcpy(&ei->dir, &info->dir, sizeof(struct exfat_chain));
	ei->entry = info->entry;
	ei->attr = info->attr;
	ei->start_clu = info->start_clu;
	ei->flags = info->flags;
	ei->type = info->type;

	ei->version = 0;
	ei->hint_stat.eidx = 0;
	ei->hint_stat.clu = info->start_clu;
	ei->hint_femp.eidx = EXFAT_HINT_NONE;
	ei->rwoffset = 0;
	ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
	ei->i_pos = 0;

	inode->i_uid = sbi->options.fs_uid;
	inode->i_gid = sbi->options.fs_gid;
	inode_inc_iversion(inode);
	inode->i_generation = prandom_u32();

	if (info->attr & ATTR_SUBDIR) { /* directory */
		inode->i_generation &= ~1;
		inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
		inode->i_op = &exfat_dir_inode_operations;
		inode->i_fop = &exfat_dir_operations;
		set_nlink(inode, info->num_subdirs);
	} else { /* regular file */
		inode->i_generation |= 1;
		inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
		inode->i_op = &exfat_file_inode_operations;
		inode->i_fop = &exfat_file_operations;
		inode->i_mapping->a_ops = &exfat_aops;
		inode->i_mapping->nrpages = 0;
	}

	i_size_write(inode, size);

	/* ondisk and aligned size should be aligned with block size */
	if (size & (inode->i_sb->s_blocksize - 1)) {
		size |= (inode->i_sb->s_blocksize - 1);
		size++;
	}

	ei->i_size_aligned = size;
	ei->i_size_ondisk = size;

	exfat_save_attr(inode, info->attr);

	inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) &
		~(sbi->cluster_size - 1)) >> inode->i_blkbits;
	inode->i_mtime = info->mtime;
	inode->i_ctime = info->mtime;
	ei->i_crtime = info->crtime;
	inode->i_atime = info->atime;

	exfat_cache_init_inode(inode);

	return 0;
}

struct inode *exfat_build_inode(struct super_block *sb,
		struct exfat_dir_entry *info, loff_t i_pos)
{
	struct inode *inode;
	int err;

	inode = exfat_iget(sb, i_pos);
	if (inode)
		goto out;
	inode = new_inode(sb);
	if (!inode) {
		inode = ERR_PTR(-ENOMEM);
		goto out;
	}
	inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
	inode_set_iversion(inode, 1);
	err = exfat_fill_inode(inode, info);
	if (err) {
		iput(inode);
		inode = ERR_PTR(err);
		goto out;
	}
	exfat_hash_inode(inode, i_pos);
	insert_inode_hash(inode);
out:
	return inode;
}

void exfat_evict_inode(struct inode *inode)
{
	truncate_inode_pages(&inode->i_data, 0);

	if (!inode->i_nlink) {
		i_size_write(inode, 0);
		mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
		__exfat_truncate(inode, 0);
		mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
	}

	invalidate_inode_buffers(inode);
	clear_inode(inode);
	exfat_cache_inval_inode(inode);
	exfat_unhash_inode(inode);
}
Commit	Line	Data
5f2aa075 NJ	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	/*
	3	* Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
	4	*/
	5
	6	#include <linux/init.h>
	7	#include <linux/buffer_head.h>
	8	#include <linux/mpage.h>
	9	#include <linux/bio.h>
	10	#include <linux/blkdev.h>
	11	#include <linux/time.h>
	12	#include <linux/writeback.h>
	13	#include <linux/uio.h>
	14	#include <linux/random.h>
	15	#include <linux/iversion.h>
	16
	17	#include "exfat_raw.h"
	18	#include "exfat_fs.h"
	19
	20	static int __exfat_write_inode(struct inode *inode, int sync)
	21	{
	22	int ret = -EIO;
	23	unsigned long long on_disk_size;
	24	struct exfat_dentry ep, ep2;
	25	struct exfat_entry_set_cache *es = NULL;
	26	struct super_block *sb = inode->i_sb;
	27	struct exfat_sb_info *sbi = EXFAT_SB(sb);
	28	struct exfat_inode_info *ei = EXFAT_I(inode);
	29	bool is_dir = (ei->type == TYPE_DIR) ? true : false;
	30
	31	if (inode->i_ino == EXFAT_ROOT_INO)
	32	return 0;
	33
	34	/*
	35	* If the indode is already unlinked, there is no need for updating it.
	36	*/
	37	if (ei->dir.dir == DIR_DELETED)
	38	return 0;
	39
	40	if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)
	41	return 0;
	42
	43	exfat_set_vol_flags(sb, VOL_DIRTY);
	44
	45	/* get the directory entry of given file or directory */
	46	es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES,
	47	&ep);
	48	if (!es)
	49	return -EIO;
	50	ep2 = ep + 1;
	51
	52	ep->dentry.file.attr = cpu_to_le16(exfat_make_attr(inode));
	53
	54	/* set FILE_INFO structure using the acquired struct exfat_dentry */
	55	exfat_set_entry_time(sbi, &ei->i_crtime,
	56	&ep->dentry.file.create_tz,
	57	&ep->dentry.file.create_time,
	58	&ep->dentry.file.create_date,
	59	&ep->dentry.file.create_time_ms);
	60	exfat_set_entry_time(sbi, &inode->i_mtime,
	61	&ep->dentry.file.modify_tz,
	62	&ep->dentry.file.modify_time,
	63	&ep->dentry.file.modify_date,
	64	&ep->dentry.file.modify_time_ms);
65	exfat_set_entry_time(sbi, &inode->i_atime,
66	&ep->dentry.file.access_tz,
67	&ep->dentry.file.access_time,
68	&ep->dentry.file.access_date,
69	NULL);
70
71	/* File size should be zero if there is no cluster allocated */
72	on_disk_size = i_size_read(inode);
73
74	if (ei->start_clu == EXFAT_EOF_CLUSTER)
75	on_disk_size = 0;
76
77	ep2->dentry.stream.valid_size = cpu_to_le64(on_disk_size);
78	ep2->dentry.stream.size = ep2->dentry.stream.valid_size;
79
80	ret = exfat_update_dir_chksum_with_entry_set(sb, es, sync);
81	kfree(es);
82	return ret;
83	}
84
85	int exfat_write_inode(struct inode inode, struct writeback_control wbc)
86	{
87	int ret;
88
89	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
90	ret = __exfat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
91	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
92
93	return ret;
94	}
95
96	void exfat_sync_inode(struct inode *inode)
97	{
98	lockdep_assert_held(&EXFAT_SB(inode->i_sb)->s_lock);
99	__exfat_write_inode(inode, 1);
100	}
101
102	/*
103	* Input: inode, (logical) clu_offset, target allocation area
104	* Output: errcode, cluster number
105	* *clu = (~0), if it's unable to allocate a new cluster
106	*/
107	static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,
108	unsigned int *clu, int create)
109	{
110	int ret, modified = false;
111	unsigned int last_clu;
112	struct exfat_chain new_clu;
113	struct exfat_dentry *ep;
114	struct exfat_entry_set_cache *es = NULL;
115	struct super_block *sb = inode->i_sb;
116	struct exfat_sb_info *sbi = EXFAT_SB(sb);
117	struct exfat_inode_info *ei = EXFAT_I(inode);
118	unsigned int local_clu_offset = clu_offset;
119	unsigned int num_to_be_allocated = 0, num_clusters = 0;
120
121	ei->rwoffset = EXFAT_CLU_TO_B(clu_offset, sbi);
122
123	if (EXFAT_I(inode)->i_size_ondisk > 0)
124	num_clusters =
125	EXFAT_B_TO_CLU_ROUND_UP(EXFAT_I(inode)->i_size_ondisk,
126	sbi);
127
128	if (clu_offset >= num_clusters)
129	num_to_be_allocated = clu_offset - num_clusters + 1;
130
131	if (!create && (num_to_be_allocated > 0)) {
132	*clu = EXFAT_EOF_CLUSTER;
133	return 0;
134	}
135
136	*clu = last_clu = ei->start_clu;
137
138	if (ei->flags == ALLOC_NO_FAT_CHAIN) {
139	if (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
140	last_clu += clu_offset - 1;
141
142	if (clu_offset == num_clusters)
143	*clu = EXFAT_EOF_CLUSTER;
144	else
145	*clu += clu_offset;
146	}
147	} else if (ei->type == TYPE_FILE) {
148	unsigned int fclus = 0;
149	int err = exfat_get_cluster(inode, clu_offset,
150	&fclus, clu, &last_clu, 1);
151	if (err)
152	return -EIO;
153
154	clu_offset -= fclus;
155	} else {
156	/* hint information */
157	if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER &&
158	ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) {
159	clu_offset -= ei->hint_bmap.off;
160	/* hint_bmap.clu should be valid */
161	WARN_ON(ei->hint_bmap.clu < 2);
162	*clu = ei->hint_bmap.clu;
163	}
164
165	while (clu_offset > 0 && *clu != EXFAT_EOF_CLUSTER) {
166	last_clu = *clu;
167	if (exfat_get_next_cluster(sb, clu))
168	return -EIO;
169	clu_offset--;
170	}
171	}
172
173	if (*clu == EXFAT_EOF_CLUSTER) {
174	exfat_set_vol_flags(sb, VOL_DIRTY);
175
176	new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?
177	EXFAT_EOF_CLUSTER : last_clu + 1;
178	new_clu.size = 0;
179	new_clu.flags = ei->flags;
180
181	/* allocate a cluster */
182	if (num_to_be_allocated < 1) {
183	/* Broken FAT (i_sze > allocated FAT) */
184	exfat_fs_error(sb, "broken FAT chain.");
185	return -EIO;
186	}
187
188	ret = exfat_alloc_cluster(inode, num_to_be_allocated, &new_clu);
189	if (ret)
190	return ret;
191
192	if (new_clu.dir == EXFAT_EOF_CLUSTER \|\|
193	new_clu.dir == EXFAT_FREE_CLUSTER) {
194	exfat_fs_error(sb,
195	"bogus cluster new allocated (last_clu : %u, new_clu : %u)",
196	last_clu, new_clu.dir);
197	return -EIO;
198	}
199
200	/* append to the FAT chain */
201	if (last_clu == EXFAT_EOF_CLUSTER) {
202	if (new_clu.flags == ALLOC_FAT_CHAIN)
203	ei->flags = ALLOC_FAT_CHAIN;
204	ei->start_clu = new_clu.dir;
205	modified = true;
206	} else {
207	if (new_clu.flags != ei->flags) {
208	/* no-fat-chain bit is disabled,
209	* so fat-chain should be synced with
210	* alloc-bitmap
211	*/
212	exfat_chain_cont_cluster(sb, ei->start_clu,
213	num_clusters);
214	ei->flags = ALLOC_FAT_CHAIN;
215	modified = true;
216	}
217	if (new_clu.flags == ALLOC_FAT_CHAIN)
218	if (exfat_ent_set(sb, last_clu, new_clu.dir))
219	return -EIO;
220	}
221
222	num_clusters += num_to_be_allocated;
223	*clu = new_clu.dir;
224
225	if (ei->dir.dir != DIR_DELETED) {
226	es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry,
227	ES_ALL_ENTRIES, &ep);
228	if (!es)
229	return -EIO;
230	/* get stream entry */
231	ep++;
232
233	/* update directory entry */
234	if (modified) {
235	if (ep->dentry.stream.flags != ei->flags)
236	ep->dentry.stream.flags = ei->flags;
237
238	if (le32_to_cpu(ep->dentry.stream.start_clu) !=
239	ei->start_clu)
240	ep->dentry.stream.start_clu =
241	cpu_to_le32(ei->start_clu);
242
243	ep->dentry.stream.valid_size =
244	cpu_to_le64(i_size_read(inode));
245	ep->dentry.stream.size =
246	ep->dentry.stream.valid_size;
247	}
248
249	if (exfat_update_dir_chksum_with_entry_set(sb, es,
250	inode_needs_sync(inode)))
251	return -EIO;
252	kfree(es);
253
254	} /* end of if != DIR_DELETED */
255
256	inode->i_blocks +=
257	num_to_be_allocated << sbi->sect_per_clus_bits;
258
259	/*
260	* Move *clu pointer along FAT chains (hole care) because the
261	* caller of this function expect *clu to be the last cluster.
262	* This only works when num_to_be_allocated >= 2,
263	* *clu = (the first cluster of the allocated chain) =>
264	* (the last cluster of ...)
265	*/
266	if (ei->flags == ALLOC_NO_FAT_CHAIN) {
267	*clu += num_to_be_allocated - 1;
268	} else {
269	while (num_to_be_allocated > 1) {
270	if (exfat_get_next_cluster(sb, clu))
271	return -EIO;
272	num_to_be_allocated--;
273	}
274	}
275
276	}
277
278	/* hint information */
279	ei->hint_bmap.off = local_clu_offset;
280	ei->hint_bmap.clu = *clu;
281
282	return 0;
283	}
284
285	static int exfat_map_new_buffer(struct exfat_inode_info *ei,
286	struct buffer_head *bh, loff_t pos)
287	{
288	if (buffer_delay(bh) && pos > ei->i_size_aligned)
289	return -EIO;
290	set_buffer_new(bh);
291
292	/*
293	* Adjust i_size_aligned if i_size_ondisk is bigger than it.
294	*/
295	if (ei->i_size_ondisk > ei->i_size_aligned)
296	ei->i_size_aligned = ei->i_size_ondisk;
297	return 0;
298	}
299
300	static int exfat_get_block(struct inode *inode, sector_t iblock,
301	struct buffer_head *bh_result, int create)
302	{
303	struct exfat_inode_info *ei = EXFAT_I(inode);
304	struct super_block *sb = inode->i_sb;
305	struct exfat_sb_info *sbi = EXFAT_SB(sb);
306	unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
307	int err = 0;
308	unsigned long mapped_blocks = 0;
309	unsigned int cluster, sec_offset;
310	sector_t last_block;
311	sector_t phys = 0;
312	loff_t pos;
313
314	mutex_lock(&sbi->s_lock);
315	last_block = EXFAT_B_TO_BLK_ROUND_UP(i_size_read(inode), sb);
316	if (iblock >= last_block && !create)
317	goto done;
318
319	/* Is this block already allocated? */
320	err = exfat_map_cluster(inode, iblock >> sbi->sect_per_clus_bits,
321	&cluster, create);
322	if (err) {
323	if (err != -ENOSPC)
324	exfat_fs_error_ratelimit(sb,
325	"failed to bmap (inode : %p iblock : %llu, err : %d)",
326	inode, (unsigned long long)iblock, err);
327	goto unlock_ret;
328	}
329
330	if (cluster == EXFAT_EOF_CLUSTER)
331	goto done;
332
333	/* sector offset in cluster */
334	sec_offset = iblock & (sbi->sect_per_clus - 1);
335
336	phys = exfat_cluster_to_sector(sbi, cluster) + sec_offset;
337	mapped_blocks = sbi->sect_per_clus - sec_offset;
338	max_blocks = min(mapped_blocks, max_blocks);
339
340	/* Treat newly added block / cluster */
341	if (iblock < last_block)
342	create = 0;
343
344	if (create \|\| buffer_delay(bh_result)) {
345	pos = EXFAT_BLK_TO_B((iblock + 1), sb);
346	if (ei->i_size_ondisk < pos)
347	ei->i_size_ondisk = pos;
348	}
349
350	if (create) {
351	err = exfat_map_new_buffer(ei, bh_result, pos);
352	if (err) {
353	exfat_fs_error(sb,
354	"requested for bmap out of range(pos : (%llu) > i_size_aligned(%llu)\n",
355	pos, ei->i_size_aligned);
356	goto unlock_ret;
357	}
358	}
359
360	if (buffer_delay(bh_result))
361	clear_buffer_delay(bh_result);
362	map_bh(bh_result, sb, phys);
363	done:
364	bh_result->b_size = EXFAT_BLK_TO_B(max_blocks, sb);
365	unlock_ret:
366	mutex_unlock(&sbi->s_lock);
367	return err;
368	}
369
370	static int exfat_readpage(struct file file, struct page page)
371	{
372	return mpage_readpage(page, exfat_get_block);
373	}
374
375	static int exfat_readpages(struct file file, struct address_space mapping,
376	struct list_head *pages, unsigned int nr_pages)
377	{
378	return mpage_readpages(mapping, pages, nr_pages, exfat_get_block);
379	}
380
381	static int exfat_writepage(struct page page, struct writeback_control wbc)
382	{
383	return block_write_full_page(page, exfat_get_block, wbc);
384	}
385
386	static int exfat_writepages(struct address_space *mapping,
387	struct writeback_control *wbc)
388	{
389	return mpage_writepages(mapping, wbc, exfat_get_block);
390	}
391
392	static void exfat_write_failed(struct address_space *mapping, loff_t to)
393	{
394	struct inode *inode = mapping->host;
395
396	if (to > i_size_read(inode)) {
397	truncate_pagecache(inode, i_size_read(inode));
398	exfat_truncate(inode, EXFAT_I(inode)->i_size_aligned);
399	}
400	}
401
402	static int exfat_write_begin(struct file file, struct address_space mapping,
403	loff_t pos, unsigned int len, unsigned int flags,
404	struct page pagep, void fsdata)
405	{
406	int ret;
407
408	*pagep = NULL;
409	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
410	exfat_get_block,
411	&EXFAT_I(mapping->host)->i_size_ondisk);
412
413	if (ret < 0)
414	exfat_write_failed(mapping, pos+len);
415
416	return ret;
417	}
418
419	static int exfat_write_end(struct file file, struct address_space mapping,
420	loff_t pos, unsigned int len, unsigned int copied,
421	struct page pagep, void fsdata)
422	{
423	struct inode *inode = mapping->host;
424	struct exfat_inode_info *ei = EXFAT_I(inode);
425	int err;
426
427	err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
428
429	if (EXFAT_I(inode)->i_size_aligned < i_size_read(inode)) {
430	exfat_fs_error(inode->i_sb,
431	"invalid size(size(%llu) > aligned(%llu)\n",
432	i_size_read(inode), EXFAT_I(inode)->i_size_aligned);
433	return -EIO;
434	}
435
436	if (err < len)
437	exfat_write_failed(mapping, pos+len);
438
439	if (!(err < 0) && !(ei->attr & ATTR_ARCHIVE)) {
440	inode->i_mtime = inode->i_ctime = current_time(inode);
441	ei->attr \|= ATTR_ARCHIVE;
442	mark_inode_dirty(inode);
443	}
444
445	return err;
446	}
447
448	static ssize_t exfat_direct_IO(struct kiocb iocb, struct iov_iter iter)
449	{
450	struct address_space *mapping = iocb->ki_filp->f_mapping;
451	struct inode *inode = mapping->host;
452	loff_t size = iocb->ki_pos + iov_iter_count(iter);
453	int rw = iov_iter_rw(iter);
454	ssize_t ret;
455
456	if (rw == WRITE) {
457	/*
458	* FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
459	* so we need to update the ->i_size_aligned to block boundary.
460	*
461	* But we must fill the remaining area or hole by nul for
462	* updating ->i_size_aligned
463	*
464	* Return 0, and fallback to normal buffered write.
465	*/
466	if (EXFAT_I(inode)->i_size_aligned < size)
467	return 0;
468	}
469
470	/*
471	* Need to use the DIO_LOCKING for avoiding the race
472	* condition of exfat_get_block() and ->truncate().
473	*/
474	ret = blockdev_direct_IO(iocb, inode, iter, exfat_get_block);
475	if (ret < 0 && (rw & WRITE))
476	exfat_write_failed(mapping, size);
477	return ret;
478	}
479
480	static sector_t exfat_aop_bmap(struct address_space *mapping, sector_t block)
481	{
482	sector_t blocknr;
483
484	/* exfat_get_cluster() assumes the requested blocknr isn't truncated. */
485	down_read(&EXFAT_I(mapping->host)->truncate_lock);
486	blocknr = generic_block_bmap(mapping, block, exfat_get_block);
487	up_read(&EXFAT_I(mapping->host)->truncate_lock);
488	return blocknr;
489	}
490
491	/*
492	* exfat_block_truncate_page() zeroes out a mapping from file offset `from'
493	* up to the end of the block which corresponds to `from'.
494	* This is required during truncate to physically zeroout the tail end
495	* of that block so it doesn't yield old data if the file is later grown.
496	* Also, avoid causing failure from fsx for cases of "data past EOF"
497	*/
498	int exfat_block_truncate_page(struct inode *inode, loff_t from)
499	{
500	return block_truncate_page(inode->i_mapping, from, exfat_get_block);
501	}
502
503	static const struct address_space_operations exfat_aops = {
504	.readpage = exfat_readpage,
505	.readpages = exfat_readpages,
506	.writepage = exfat_writepage,
507	.writepages = exfat_writepages,
508	.write_begin = exfat_write_begin,
509	.write_end = exfat_write_end,
510	.direct_IO = exfat_direct_IO,
511	.bmap = exfat_aop_bmap
512	};
513
514	static inline unsigned long exfat_hash(loff_t i_pos)
515	{
516	return hash_32(i_pos, EXFAT_HASH_BITS);
517	}
518
519	void exfat_hash_inode(struct inode *inode, loff_t i_pos)
520	{
521	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
522	struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
523
524	spin_lock(&sbi->inode_hash_lock);
525	EXFAT_I(inode)->i_pos = i_pos;
526	hlist_add_head(&EXFAT_I(inode)->i_hash_fat, head);
527	spin_unlock(&sbi->inode_hash_lock);
528	}
529
530	void exfat_unhash_inode(struct inode *inode)
531	{
532	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
533
534	spin_lock(&sbi->inode_hash_lock);
535	hlist_del_init(&EXFAT_I(inode)->i_hash_fat);
536	EXFAT_I(inode)->i_pos = 0;
537	spin_unlock(&sbi->inode_hash_lock);
538	}
539
540	struct inode exfat_iget(struct super_block sb, loff_t i_pos)
541	{
542	struct exfat_sb_info *sbi = EXFAT_SB(sb);
543	struct exfat_inode_info *info;
544	struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
545	struct inode *inode = NULL;
546
547	spin_lock(&sbi->inode_hash_lock);
548	hlist_for_each_entry(info, head, i_hash_fat) {
549	WARN_ON(info->vfs_inode.i_sb != sb);
550
551	if (i_pos != info->i_pos)
552	continue;
553	inode = igrab(&info->vfs_inode);
554	if (inode)
555	break;
556	}
557	spin_unlock(&sbi->inode_hash_lock);
558	return inode;
559	}
560
561	/* doesn't deal with root inode */
562	static int exfat_fill_inode(struct inode inode, struct exfat_dir_entry info)
563	{
564	struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
565	struct exfat_inode_info *ei = EXFAT_I(inode);
566	loff_t size = info->size;
567
568	memcpy(&ei->dir, &info->dir, sizeof(struct exfat_chain));
569	ei->entry = info->entry;
570	ei->attr = info->attr;
571	ei->start_clu = info->start_clu;
572	ei->flags = info->flags;
573	ei->type = info->type;
574
575	ei->version = 0;
576	ei->hint_stat.eidx = 0;
577	ei->hint_stat.clu = info->start_clu;
578	ei->hint_femp.eidx = EXFAT_HINT_NONE;
579	ei->rwoffset = 0;
580	ei->hint_bmap.off = EXFAT_EOF_CLUSTER;
581	ei->i_pos = 0;
582
583	inode->i_uid = sbi->options.fs_uid;
584	inode->i_gid = sbi->options.fs_gid;
585	inode_inc_iversion(inode);
586	inode->i_generation = prandom_u32();
587
588	if (info->attr & ATTR_SUBDIR) { /* directory */
589	inode->i_generation &= ~1;
590	inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
591	inode->i_op = &exfat_dir_inode_operations;
592	inode->i_fop = &exfat_dir_operations;
593	set_nlink(inode, info->num_subdirs);
594	} else { /* regular file */
595	inode->i_generation \|= 1;
596	inode->i_mode = exfat_make_mode(sbi, info->attr, 0777);
597	inode->i_op = &exfat_file_inode_operations;
598	inode->i_fop = &exfat_file_operations;
599	inode->i_mapping->a_ops = &exfat_aops;
600	inode->i_mapping->nrpages = 0;
601	}
602
603	i_size_write(inode, size);
604
605	/* ondisk and aligned size should be aligned with block size */
606	if (size & (inode->i_sb->s_blocksize - 1)) {
607	size \|= (inode->i_sb->s_blocksize - 1);
608	size++;
609	}
610
611	ei->i_size_aligned = size;
612	ei->i_size_ondisk = size;
613
614	exfat_save_attr(inode, info->attr);
615
616	inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) &
617	~(sbi->cluster_size - 1)) >> inode->i_blkbits;
618	inode->i_mtime = info->mtime;
619	inode->i_ctime = info->mtime;
620	ei->i_crtime = info->crtime;
621	inode->i_atime = info->atime;
622
623	exfat_cache_init_inode(inode);
624
625	return 0;
626	}
627
628	struct inode exfat_build_inode(struct super_block sb,
629	struct exfat_dir_entry *info, loff_t i_pos)
630	{
631	struct inode *inode;
632	int err;
633
634	inode = exfat_iget(sb, i_pos);
635	if (inode)
636	goto out;
637	inode = new_inode(sb);
638	if (!inode) {
639	inode = ERR_PTR(-ENOMEM);
640	goto out;
641	}
642	inode->i_ino = iunique(sb, EXFAT_ROOT_INO);
643	inode_set_iversion(inode, 1);
644	err = exfat_fill_inode(inode, info);
645	if (err) {
646	iput(inode);
647	inode = ERR_PTR(err);
648	goto out;
649	}
650	exfat_hash_inode(inode, i_pos);
651	insert_inode_hash(inode);
652	out:
653	return inode;
654	}
655
656	void exfat_evict_inode(struct inode *inode)
657	{
658	truncate_inode_pages(&inode->i_data, 0);
659
660	if (!inode->i_nlink) {
661	i_size_write(inode, 0);
662	mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
663	__exfat_truncate(inode, 0);
664	mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
665	}
666
667	invalidate_inode_buffers(inode);
668	clear_inode(inode);
669	exfat_cache_inval_inode(inode);
670	exfat_unhash_inode(inode);
671	}