path: root/fs/f2fs/extent_cache.c

// SPDX-License-Identifier: GPL-2.0
/*
 * f2fs extent cache support
 *
 * Copyright (c) 2015 Motorola Mobility
 * Copyright (c) 2015 Samsung Electronics
 * Authors: Jaegeuk Kim <jaegeuk@kernel.org>
 *          Chao Yu <chao2.yu@samsung.com>
 *
 * block_age-based extent cache added by:
 * Copyright (c) 2022 xiaomi Co., Ltd.
 *             http://www.xiaomi.com/
 */

#include <linux/fs.h>
#include <linux/f2fs_fs.h>

#include "f2fs.h"
#include "node.h"
#include <trace/events/f2fs.h>

static void __set_extent_info(struct extent_info *ei,
				unsigned int fofs, unsigned int len,
				block_t blk, bool keep_clen,
				unsigned long age, unsigned long last_blocks,
				enum extent_type type)
{
	ei->fofs = fofs;
	ei->len = len;

	if (type == EX_READ) {
		ei->blk = blk;
		if (keep_clen)
			return;
#ifdef CONFIG_F2FS_FS_COMPRESSION
		ei->c_len = 0;
#endif
	} else if (type == EX_BLOCK_AGE) {
		ei->age = age;
		ei->last_blocks = last_blocks;
	}
}

static bool __may_read_extent_tree(struct inode *inode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

	if (!test_opt(sbi, READ_EXTENT_CACHE))
		return false;
	if (is_inode_flag_set(inode, FI_NO_EXTENT))
		return false;
	if (is_inode_flag_set(inode, FI_COMPRESSED_FILE) &&
			 !f2fs_sb_has_readonly(sbi))
		return false;
	return S_ISREG(inode->i_mode);
}

static bool __may_age_extent_tree(struct inode *inode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

	if (!test_opt(sbi, AGE_EXTENT_CACHE))
		return false;
	/* don't cache block age info for cold file */
	if (is_inode_flag_set(inode, FI_COMPRESSED_FILE))
		return false;
	if (file_is_cold(inode))
		return false;

	return S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode);
}

static bool __init_may_extent_tree(struct inode *inode, enum extent_type type)
{
	if (type == EX_READ)
		return __may_read_extent_tree(inode);
	else if (type == EX_BLOCK_AGE)
		return __may_age_extent_tree(inode);
	return false;
}

static bool __may_extent_tree(struct inode *inode, enum extent_type type)
{
	/*
	 * for recovered files during mount do not create extents
	 * if shrinker is not registered.
	 */
	if (list_empty(&F2FS_I_SB(inode)->s_list))
		return false;

	return __init_may_extent_tree(inode, type);
}

static void __try_update_largest_extent(struct extent_tree *et,
						struct extent_node *en)
{
	if (et->type != EX_READ)
		return;
	if (en->ei.len <= et->largest.len)
		return;

	et->largest = en->ei;
	et->largest_updated = true;
}

static bool __is_extent_mergeable(struct extent_info *back,
		struct extent_info *front, enum extent_type type)
{
	if (type == EX_READ) {
#ifdef CONFIG_F2FS_FS_COMPRESSION
		if (back->c_len && back->len != back->c_len)