Commit ef8d563f authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
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f2fs: introduce F2FS_IOC_RELEASE_COMPRESS_BLOCKS 



There are still reserved blocks on compressed inode, this patch
introduce a new ioctl to help release reserved blocks back to
filesystem, so that userspace can reuse those freed space.

----
Daeho fixed a bug like below.

Now, if writing pages and releasing compress blocks occur
simultaneously, and releasing cblocks is executed more than one time
to a file, then total block count of filesystem and block count of the
file could be incorrect and damaged.

We have to execute releasing compress blocks only one time for a file
without being interfered by writepages path.
---

Signed-off-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarDaeho Jeong <daehojeong@google.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 042be373

fs/f2fs/f2fs.h

+6 −0
Original line number Diff line number Diff line
@@ -428,6 +428,8 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, 
#define F2FS_IOC_PRECACHE_EXTENTS	_IO(F2FS_IOCTL_MAGIC, 15)

#define F2FS_IOC_RESIZE_FS		_IOW(F2FS_IOCTL_MAGIC, 16, __u64)

#define F2FS_IOC_GET_COMPRESS_BLOCKS	_IOR(F2FS_IOCTL_MAGIC, 17, __u64)

#define F2FS_IOC_RELEASE_COMPRESS_BLOCKS				\

					_IOR(F2FS_IOCTL_MAGIC, 18, __u64)



#define F2FS_IOC_GET_VOLUME_NAME	FS_IOC_GETFSLABEL

#define F2FS_IOC_SET_VOLUME_NAME	FS_IOC_SETFSLABEL
@@ -4048,6 +4050,10 @@ static inline void f2fs_i_compr_blocks_update(struct inode *inode, 
{

	int diff = F2FS_I(inode)->i_cluster_size - blocks;



	/* don't update i_compr_blocks if saved blocks were released */

	if (!add && !F2FS_I(inode)->i_compr_blocks)

		return;



	if (add) {

		F2FS_I(inode)->i_compr_blocks += diff;

		stat_add_compr_blocks(inode, diff);

fs/f2fs/file.c

+168 −1
Original line number Diff line number Diff line
@@ -563,6 +563,7 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count) 
	bool compressed_cluster = false;

	int cluster_index = 0, valid_blocks = 0;

	int cluster_size = F2FS_I(dn->inode)->i_cluster_size;

	bool released = !F2FS_I(dn->inode)->i_compr_blocks;



	if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode))

		base = get_extra_isize(dn->inode);
@@ -601,6 +602,8 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count) 
			clear_inode_flag(dn->inode, FI_FIRST_BLOCK_WRITTEN);



		f2fs_invalidate_blocks(sbi, blkaddr);



		if (!released || blkaddr != COMPRESS_ADDR)

			nr_free++;

	}
@@ -3434,6 +3437,167 @@ static int f2fs_get_compress_blocks(struct file *filp, unsigned long arg) 
	return put_user(blocks, (u64 __user *)arg);

}



static int release_compress_blocks(struct dnode_of_data *dn, pgoff_t count)

{

	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);

	unsigned int released_blocks = 0;

	int cluster_size = F2FS_I(dn->inode)->i_cluster_size;

	block_t blkaddr;

	int i;



	for (i = 0; i < count; i++) {

		blkaddr = data_blkaddr(dn->inode, dn->node_page,

						dn->ofs_in_node + i);



		if (!__is_valid_data_blkaddr(blkaddr))

			continue;

		if (unlikely(!f2fs_is_valid_blkaddr(sbi, blkaddr,

					DATA_GENERIC_ENHANCE)))

			return -EFSCORRUPTED;

	}



	while (count) {

		int compr_blocks = 0;



		for (i = 0; i < cluster_size; i++, dn->ofs_in_node++) {

			blkaddr = f2fs_data_blkaddr(dn);



			if (i == 0) {

				if (blkaddr == COMPRESS_ADDR)

					continue;

				dn->ofs_in_node += cluster_size;

				goto next;

			}



			if (__is_valid_data_blkaddr(blkaddr))

				compr_blocks++;



			if (blkaddr != NEW_ADDR)

				continue;



			dn->data_blkaddr = NULL_ADDR;

			f2fs_set_data_blkaddr(dn);

		}



		f2fs_i_compr_blocks_update(dn->inode, compr_blocks, false);

		dec_valid_block_count(sbi, dn->inode,

					cluster_size - compr_blocks);



		released_blocks += cluster_size - compr_blocks;

next:

		count -= cluster_size;

	}



	return released_blocks;

}



static int f2fs_release_compress_blocks(struct file *filp, unsigned long arg)

{

	struct inode *inode = file_inode(filp);

	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

	pgoff_t page_idx = 0, last_idx;

	unsigned int released_blocks = 0;

	int ret;

	int writecount;



	if (!f2fs_sb_has_compression(F2FS_I_SB(inode)))

		return -EOPNOTSUPP;



	if (!f2fs_compressed_file(inode))

		return -EINVAL;



	if (f2fs_readonly(sbi->sb))

		return -EROFS;



	ret = mnt_want_write_file(filp);

	if (ret)

		return ret;



	f2fs_balance_fs(F2FS_I_SB(inode), true);



	inode_lock(inode);



	writecount = atomic_read(&inode->i_writecount);

	if ((filp->f_mode & FMODE_WRITE && writecount != 1) || writecount) {

		ret = -EBUSY;

		goto out;

	}



	if (IS_IMMUTABLE(inode)) {

		ret = -EINVAL;

		goto out;

	}



	ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX);

	if (ret)

		goto out;



	if (!F2FS_I(inode)->i_compr_blocks)

		goto out;



	F2FS_I(inode)->i_flags |= F2FS_IMMUTABLE_FL;

	f2fs_set_inode_flags(inode);

	inode->i_ctime = current_time(inode);

	f2fs_mark_inode_dirty_sync(inode, true);



	down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);

	down_write(&F2FS_I(inode)->i_mmap_sem);



	last_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);



	while (page_idx < last_idx) {

		struct dnode_of_data dn;

		pgoff_t end_offset, count;



		set_new_dnode(&dn, inode, NULL, NULL, 0);

		ret = f2fs_get_dnode_of_data(&dn, page_idx, LOOKUP_NODE);

		if (ret) {

			if (ret == -ENOENT) {

				page_idx = f2fs_get_next_page_offset(&dn,

								page_idx);

				ret = 0;

				continue;

			}

			break;

		}



		end_offset = ADDRS_PER_PAGE(dn.node_page, inode);

		count = min(end_offset - dn.ofs_in_node, last_idx - page_idx);

		count = roundup(count, F2FS_I(inode)->i_cluster_size);



		ret = release_compress_blocks(&dn, count);



		f2fs_put_dnode(&dn);



		if (ret < 0)

			break;



		page_idx += count;

		released_blocks += ret;

	}



	up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);

	up_write(&F2FS_I(inode)->i_mmap_sem);

out:

	inode_unlock(inode);



	mnt_drop_write_file(filp);



	if (ret >= 0) {

		ret = put_user(released_blocks, (u64 __user *)arg);

	} else if (released_blocks && F2FS_I(inode)->i_compr_blocks) {

		set_sbi_flag(sbi, SBI_NEED_FSCK);

		f2fs_warn(sbi, "%s: partial blocks were released i_ino=%lx "

			"iblocks=%llu, released=%u, compr_blocks=%llu, "

			"run fsck to fix.",

			__func__, inode->i_ino, inode->i_blocks,

			released_blocks,

			F2FS_I(inode)->i_compr_blocks);

	}



	return ret;

}



long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)

{

	if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(filp)))))
@@ -3516,6 +3680,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 
		return f2fs_set_volume_name(filp, arg);

	case F2FS_IOC_GET_COMPRESS_BLOCKS:

		return f2fs_get_compress_blocks(filp, arg);

	case F2FS_IOC_RELEASE_COMPRESS_BLOCKS:

		return f2fs_release_compress_blocks(filp, arg);

	default:

		return -ENOTTY;

	}
@@ -3683,6 +3849,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	case F2FS_IOC_GET_VOLUME_NAME:

	case F2FS_IOC_SET_VOLUME_NAME:

	case F2FS_IOC_GET_COMPRESS_BLOCKS:

	case F2FS_IOC_RELEASE_COMPRESS_BLOCKS:

		break;

	default:

		return -ENOIOCTLCMD;

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