Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 860 insertions, 0 deletions

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
new file mode 100644
index 000000000..ff379aff4
--- /dev/null
+++ b/fs/f2fs/debug.c
@@ -0,0 +1,860 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * f2fs debugging statistics
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *             http://www.samsung.com/
+ * Copyright (c) 2012 Linux Foundation
+ * Copyright (c) 2012 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+ */
+
+#include <linux/fs.h>
+#include <linux/backing-dev.h>
+#include <linux/f2fs_fs.h>
+#include <linux/blkdev.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include "f2fs.h"
+#include "node.h"
+#include "segment.h"
+#include "gc.h"
+
+static LIST_HEAD(f2fs_stat_list);
+static DEFINE_SPINLOCK(f2fs_stat_lock);
+#ifdef CONFIG_DEBUG_FS
+static struct dentry *f2fs_debugfs_root;
+#endif
+
+/*
+ * This function calculates BDF of every segments
+ */
+void f2fs_update_sit_info(struct f2fs_sb_info *sbi)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+	unsigned long long blks_per_sec, hblks_per_sec, total_vblocks;
+	unsigned long long bimodal, dist;
+	unsigned int segno, vblocks;
+	int ndirty = 0;
+
+	bimodal = 0;
+	total_vblocks = 0;
+	blks_per_sec = CAP_BLKS_PER_SEC(sbi);
+	hblks_per_sec = blks_per_sec / 2;
+	for (segno = 0; segno < MAIN_SEGS(sbi); segno += SEGS_PER_SEC(sbi)) {
+		vblocks = get_valid_blocks(sbi, segno, true);
+		dist = abs(vblocks - hblks_per_sec);
+		bimodal += dist * dist;
+
+		if (vblocks > 0 && vblocks < blks_per_sec) {
+			total_vblocks += vblocks;
+			ndirty++;
+		}
+	}
+	dist = div_u64(MAIN_SECS(sbi) * hblks_per_sec * hblks_per_sec, 100);
+	si->bimodal = div64_u64(bimodal, dist);
+	if (si->dirty_count)
+		si->avg_vblocks = div_u64(total_vblocks, ndirty);
+	else
+		si->avg_vblocks = 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void update_multidevice_stats(struct f2fs_sb_info *sbi)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+	struct f2fs_dev_stats *dev_stats = si->dev_stats;
+	int i, j;
+
+	if (!f2fs_is_multi_device(sbi))
+		return;
+
+	memset(dev_stats, 0, sizeof(struct f2fs_dev_stats) * sbi->s_ndevs);
+	for (i = 0; i < sbi->s_ndevs; i++) {
+		unsigned int start_segno, end_segno;
+		block_t start_blk, end_blk;
+
+		if (i == 0) {
+			start_blk = MAIN_BLKADDR(sbi);
+			end_blk = FDEV(i).end_blk + 1 - SEG0_BLKADDR(sbi);
+		} else {
+			start_blk = FDEV(i).start_blk;
+			end_blk = FDEV(i).end_blk + 1;
+		}
+
+		start_segno = GET_SEGNO(sbi, start_blk);
+		end_segno = GET_SEGNO(sbi, end_blk);
+
+		for (j = start_segno; j < end_segno; j++) {
+			unsigned int seg_blks, sec_blks;
+
+			seg_blks = get_seg_entry(sbi, j)->valid_blocks;
+
+			/* update segment stats */
+			if (is_curseg(sbi, j))
+				dev_stats[i].devstats[0][DEVSTAT_INUSE]++;
+			else if (seg_blks == BLKS_PER_SEG(sbi))
+				dev_stats[i].devstats[0][DEVSTAT_FULL]++;
+			else if (seg_blks != 0)
+				dev_stats[i].devstats[0][DEVSTAT_DIRTY]++;
+			else if (!test_bit(j, FREE_I(sbi)->free_segmap))
+				dev_stats[i].devstats[0][DEVSTAT_FREE]++;
+			else
+				dev_stats[i].devstats[0][DEVSTAT_PREFREE]++;
+
+			if (!__is_large_section(sbi) ||
+				(j % SEGS_PER_SEC(sbi)) != 0)
+				continue;
+
+			sec_blks = get_sec_entry(sbi, j)->valid_blocks;
+
+			/* update section stats */
+			if (is_cursec(sbi, GET_SEC_FROM_SEG(sbi, j)))
+				dev_stats[i].devstats[1][DEVSTAT_INUSE]++;
+			else if (sec_blks == BLKS_PER_SEC(sbi))
+				dev_stats[i].devstats[1][DEVSTAT_FULL]++;
+			else if (sec_blks != 0)
+				dev_stats[i].devstats[1][DEVSTAT_DIRTY]++;
+			else if (!test_bit(GET_SEC_FROM_SEG(sbi, j),
+					FREE_I(sbi)->free_secmap))
+				dev_stats[i].devstats[1][DEVSTAT_FREE]++;
+			else
+				dev_stats[i].devstats[1][DEVSTAT_PREFREE]++;
+		}
+	}
+}
+
+static void update_general_status(struct f2fs_sb_info *sbi)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
+	int i;
+
+	/* these will be changed if online resize is done */
+	si->main_area_segs = le32_to_cpu(raw_super->segment_count_main);
+	si->main_area_sections = le32_to_cpu(raw_super->section_count);
+	si->main_area_zones = si->main_area_sections /
+				le32_to_cpu(raw_super->secs_per_zone);
+
+	/* general extent cache stats */
+	for (i = 0; i < NR_EXTENT_CACHES; i++) {
+		struct extent_tree_info *eti = &sbi->extent_tree[i];
+
+		si->hit_cached[i] = atomic64_read(&sbi->read_hit_cached[i]);
+		si->hit_rbtree[i] = atomic64_read(&sbi->read_hit_rbtree[i]);
+		si->total_ext[i] = atomic64_read(&sbi->total_hit_ext[i]);
+		si->hit_total[i] = si->hit_cached[i] + si->hit_rbtree[i];
+		si->ext_tree[i] = atomic_read(&eti->total_ext_tree);
+		si->zombie_tree[i] = atomic_read(&eti->total_zombie_tree);
+		si->ext_node[i] = atomic_read(&eti->total_ext_node);
+	}
+	/* read extent_cache only */
+	si->hit_largest = atomic64_read(&sbi->read_hit_largest);
+	si->hit_total[EX_READ] += si->hit_largest;
+
+	/* block age extent_cache only */
+	si->allocated_data_blocks = atomic64_read(&sbi->allocated_data_blocks);
+
+	/* validation check of the segment numbers */
+	si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
+	si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
+	si->ndirty_meta = get_pages(sbi, F2FS_DIRTY_META);
+	si->ndirty_data = get_pages(sbi, F2FS_DIRTY_DATA);
+	si->ndirty_qdata = get_pages(sbi, F2FS_DIRTY_QDATA);
+	si->ndirty_imeta = get_pages(sbi, F2FS_DIRTY_IMETA);
+	si->ndirty_dirs = sbi->ndirty_inode[DIR_INODE];
+	si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
+	si->ndonate_files = sbi->donate_files;
+	si->nquota_files = sbi->nquota_files;
+	si->ndirty_all = sbi->ndirty_inode[DIRTY_META];
+	si->aw_cnt = atomic_read(&sbi->atomic_files);
+	si->max_aw_cnt = atomic_read(&sbi->max_aw_cnt);
+	si->nr_dio_read = get_pages(sbi, F2FS_DIO_READ);
+	si->nr_dio_write = get_pages(sbi, F2FS_DIO_WRITE);
+	si->nr_wb_cp_data = get_pages(sbi, F2FS_WB_CP_DATA);
+	si->nr_wb_data = get_pages(sbi, F2FS_WB_DATA);
+	si->nr_rd_data = get_pages(sbi, F2FS_RD_DATA);
+	si->nr_rd_node = get_pages(sbi, F2FS_RD_NODE);
+	si->nr_rd_meta = get_pages(sbi, F2FS_RD_META);
+	if (SM_I(sbi)->fcc_info) {
+		si->nr_flushed =
+			atomic_read(&SM_I(sbi)->fcc_info->issued_flush);
+		si->nr_flushing =
+			atomic_read(&SM_I(sbi)->fcc_info->queued_flush);
+		si->flush_list_empty =
+			llist_empty(&SM_I(sbi)->fcc_info->issue_list);
+	}
+	if (SM_I(sbi)->dcc_info) {
+		si->nr_discarded =
+			atomic_read(&SM_I(sbi)->dcc_info->issued_discard);
+		si->nr_discarding =
+			atomic_read(&SM_I(sbi)->dcc_info->queued_discard);
+		si->nr_discard_cmd =
+			atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
+		si->undiscard_blks = SM_I(sbi)->dcc_info->undiscard_blks;
+	}
+	si->nr_issued_ckpt = atomic_read(&sbi->cprc_info.issued_ckpt);
+	si->nr_total_ckpt = atomic_read(&sbi->cprc_info.total_ckpt);
+	si->nr_queued_ckpt = atomic_read(&sbi->cprc_info.queued_ckpt);
+	spin_lock(&sbi->cprc_info.stat_lock);
+	si->cur_ckpt_time = sbi->cprc_info.cur_time;
+	si->peak_ckpt_time = sbi->cprc_info.peak_time;
+	spin_unlock(&sbi->cprc_info.stat_lock);
+	si->total_count = BLKS_TO_SEGS(sbi, (int)sbi->user_block_count);
+	si->rsvd_segs = reserved_segments(sbi);
+	si->overp_segs = overprovision_segments(sbi);
+	si->valid_count = valid_user_blocks(sbi);
+	si->discard_blks = discard_blocks(sbi);
+	si->valid_node_count = valid_node_count(sbi);
+	si->valid_inode_count = valid_inode_count(sbi);
+	si->inline_xattr = atomic_read(&sbi->inline_xattr);
+	si->inline_inode = atomic_read(&sbi->inline_inode);
+	si->inline_dir = atomic_read(&sbi->inline_dir);
+	si->compr_inode = atomic_read(&sbi->compr_inode);
+	si->swapfile_inode = atomic_read(&sbi->swapfile_inode);
+	si->compr_blocks = atomic64_read(&sbi->compr_blocks);
+	si->append = sbi->im[APPEND_INO].ino_num;
+	si->update = sbi->im[UPDATE_INO].ino_num;
+	si->orphans = sbi->im[ORPHAN_INO].ino_num;
+	si->utilization = utilization(sbi);
+
+	si->free_segs = free_segments(sbi);
+	si->free_secs = free_sections(sbi);
+	si->prefree_count = prefree_segments(sbi);
+	si->dirty_count = dirty_segments(sbi);
+	if (sbi->node_inode)
+		si->node_pages = NODE_MAPPING(sbi)->nrpages;
+	if (sbi->meta_inode)
+		si->meta_pages = META_MAPPING(sbi)->nrpages;
+#ifdef CONFIG_F2FS_FS_COMPRESSION
+	if (sbi->compress_inode) {
+		si->compress_pages = COMPRESS_MAPPING(sbi)->nrpages;
+		si->compress_page_hit = atomic_read(&sbi->compress_page_hit);
+	}
+#endif
+	si->nats = NM_I(sbi)->nat_cnt[TOTAL_NAT];
+	si->dirty_nats = NM_I(sbi)->nat_cnt[DIRTY_NAT];
+	si->sits = MAIN_SEGS(sbi);
+	si->dirty_sits = SIT_I(sbi)->dirty_sentries;
+	si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID];
+	si->avail_nids = NM_I(sbi)->available_nids;
+	si->alloc_nids = NM_I(sbi)->nid_cnt[PREALLOC_NID];
+	si->io_skip_bggc = sbi->io_skip_bggc;
+	si->other_skip_bggc = sbi->other_skip_bggc;
+	si->util_free = (int)(BLKS_TO_SEGS(sbi, free_user_blocks(sbi)))
+		* 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
+		/ 2;
+	si->util_valid = (int)(BLKS_TO_SEGS(sbi, written_block_count(sbi)))
+		* 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
+		/ 2;
+	si->util_invalid = 50 - si->util_free - si->util_valid;
+	for (i = CURSEG_HOT_DATA; i < NO_CHECK_TYPE; i++) {
+		struct curseg_info *curseg = CURSEG_I(sbi, i);
+
+		si->blkoff[i] = curseg->next_blkoff;
+		si->curseg[i] = curseg->segno;
+		si->cursec[i] = GET_SEC_FROM_SEG(sbi, curseg->segno);
+		si->curzone[i] = GET_ZONE_FROM_SEC(sbi, si->cursec[i]);
+	}
+
+	for (i = META_CP; i < META_MAX; i++)
+		si->meta_count[i] = atomic_read(&sbi->meta_count[i]);
+
+	for (i = 0; i < NO_CHECK_TYPE; i++) {
+		si->dirty_seg[i] = 0;
+		si->full_seg[i] = 0;
+		si->valid_blks[i] = 0;
+	}
+
+	for (i = 0; i < MAIN_SEGS(sbi); i++) {
+		int blks = get_seg_entry(sbi, i)->valid_blocks;
+		int type = get_seg_entry(sbi, i)->type;
+
+		if (!blks)
+			continue;
+
+		if (blks == BLKS_PER_SEG(sbi))
+			si->full_seg[type]++;
+		else
+			si->dirty_seg[type]++;
+		si->valid_blks[type] += blks;
+	}
+
+	update_multidevice_stats(sbi);
+
+	for (i = 0; i < MAX_CALL_TYPE; i++)
+		si->cp_call_count[i] = atomic_read(&sbi->cp_call_count[i]);
+
+	for (i = 0; i < 2; i++) {
+		si->segment_count[i] = sbi->segment_count[i];
+		si->block_count[i] = sbi->block_count[i];
+	}
+
+	si->inplace_count = atomic_read(&sbi->inplace_count);
+}
+
+/*
+ * This function calculates memory footprint.
+ */
+static void update_mem_info(struct f2fs_sb_info *sbi)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+	int i;
+
+	if (si->base_mem)
+		goto get_cache;
+
+	/* build stat */
+	si->base_mem = sizeof(struct f2fs_stat_info);
+
+	/* build superblock */
+	si->base_mem += sizeof(struct f2fs_sb_info) + sbi->sb->s_blocksize;
+	si->base_mem += 2 * sizeof(struct f2fs_inode_info);
+	si->base_mem += sizeof(*sbi->ckpt);
+
+	/* build sm */
+	si->base_mem += sizeof(struct f2fs_sm_info);
+
+	/* build sit */
+	si->base_mem += sizeof(struct sit_info);
+	si->base_mem += MAIN_SEGS(sbi) * sizeof(struct seg_entry);
+	si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
+	si->base_mem += 2 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
+	si->base_mem += SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
+	si->base_mem += SIT_VBLOCK_MAP_SIZE;
+	if (__is_large_section(sbi))
+		si->base_mem += MAIN_SECS(sbi) * sizeof(struct sec_entry);
+	si->base_mem += __bitmap_size(sbi, SIT_BITMAP);
+
+	/* build free segmap */
+	si->base_mem += sizeof(struct free_segmap_info);
+	si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
+	si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
+
+	/* build curseg */
+	si->base_mem += sizeof(struct curseg_info) * NR_CURSEG_TYPE;
+	si->base_mem += PAGE_SIZE * NR_CURSEG_TYPE;
+
+	/* build dirty segmap */
+	si->base_mem += sizeof(struct dirty_seglist_info);
+	si->base_mem += NR_DIRTY_TYPE * f2fs_bitmap_size(MAIN_SEGS(sbi));
+	si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
+
+	/* build nm */
+	si->base_mem += sizeof(struct f2fs_nm_info);
+	si->base_mem += __bitmap_size(sbi, NAT_BITMAP);
+	si->base_mem += F2FS_BLK_TO_BYTES(NM_I(sbi)->nat_bits_blocks);
+	si->base_mem += NM_I(sbi)->nat_blocks *
+				f2fs_bitmap_size(NAT_ENTRY_PER_BLOCK);
+	si->base_mem += NM_I(sbi)->nat_blocks / 8;
+	si->base_mem += NM_I(sbi)->nat_blocks * sizeof(unsigned short);
+
+get_cache:
+	si->cache_mem = 0;
+
+	/* build merge flush thread */
+	if (SM_I(sbi)->fcc_info)
+		si->cache_mem += sizeof(struct flush_cmd_control);
+	if (SM_I(sbi)->dcc_info) {
+		si->cache_mem += sizeof(struct discard_cmd_control);
+		si->cache_mem += sizeof(struct discard_cmd) *
+			atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
+	}
+
+	/* free nids */
+	si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID] +
+				NM_I(sbi)->nid_cnt[PREALLOC_NID]) *
+				sizeof(struct free_nid);
+	si->cache_mem += NM_I(sbi)->nat_cnt[TOTAL_NAT] *
+				sizeof(struct nat_entry);
+	si->cache_mem += NM_I(sbi)->nat_cnt[DIRTY_NAT] *
+				sizeof(struct nat_entry_set);
+	for (i = 0; i < MAX_INO_ENTRY; i++)
+		si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
+
+	for (i = 0; i < NR_EXTENT_CACHES; i++) {
+		struct extent_tree_info *eti = &sbi->extent_tree[i];
+
+		si->ext_mem[i] = atomic_read(&eti->total_ext_tree) *
+						sizeof(struct extent_tree);
+		si->ext_mem[i] += atomic_read(&eti->total_ext_node) *
+						sizeof(struct extent_node);
+		si->cache_mem += si->ext_mem[i];
+	}
+
+	si->page_mem = 0;
+	if (sbi->node_inode) {
+		unsigned long npages = NODE_MAPPING(sbi)->nrpages;
+
+		si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
+	}
+	if (sbi->meta_inode) {
+		unsigned long npages = META_MAPPING(sbi)->nrpages;
+
+		si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
+	}
+#ifdef CONFIG_F2FS_FS_COMPRESSION
+	if (sbi->compress_inode) {
+		unsigned long npages = COMPRESS_MAPPING(sbi)->nrpages;
+
+		si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
+	}
+#endif
+}
+
+static const char *s_flag[MAX_SBI_FLAG] = {
+	[SBI_IS_DIRTY]		= "fs_dirty",
+	[SBI_IS_CLOSE]		= "closing",
+	[SBI_NEED_FSCK]		= "need_fsck",
+	[SBI_POR_DOING]		= "recovering",
+	[SBI_NEED_SB_WRITE]	= "sb_dirty",
+	[SBI_NEED_CP]		= "need_cp",
+	[SBI_IS_SHUTDOWN]	= "shutdown",
+	[SBI_IS_RECOVERED]	= "recovered",
+	[SBI_CP_DISABLED]	= "cp_disabled",
+	[SBI_CP_DISABLED_QUICK]	= "cp_disabled_quick",
+	[SBI_QUOTA_NEED_FLUSH]	= "quota_need_flush",
+	[SBI_QUOTA_SKIP_FLUSH]	= "quota_skip_flush",
+	[SBI_QUOTA_NEED_REPAIR]	= "quota_need_repair",
+	[SBI_IS_RESIZEFS]	= "resizefs",
+	[SBI_IS_FREEZING]	= "freezefs",
+	[SBI_IS_WRITABLE]	= "writable",
+	[SBI_ENABLE_CHECKPOINT]	= "enable_checkpoint",
+};
+
+static const char *ipu_mode_names[F2FS_IPU_MAX] = {
+	[F2FS_IPU_FORCE]	= "FORCE",
+	[F2FS_IPU_SSR]		= "SSR",
+	[F2FS_IPU_UTIL]		= "UTIL",
+	[F2FS_IPU_SSR_UTIL]	= "SSR_UTIL",
+	[F2FS_IPU_FSYNC]	= "FSYNC",
+	[F2FS_IPU_ASYNC]	= "ASYNC",
+	[F2FS_IPU_NOCACHE]	= "NOCACHE",
+	[F2FS_IPU_HONOR_OPU_WRITE]	= "HONOR_OPU_WRITE",
+};
+
+static int stat_show(struct seq_file *s, void *v)
+{
+	struct f2fs_stat_info *si;
+	int i = 0, j = 0;
+
+	spin_lock(&f2fs_stat_lock);
+	list_for_each_entry(si, &f2fs_stat_list, stat_list) {
+		struct f2fs_sb_info *sbi = si->sbi;
+
+		update_general_status(sbi);
+
+		seq_printf(s, "\n=====[ partition info(%pg). #%d, %s, CP: %s]=====\n",
+			sbi->sb->s_bdev, i++,
+			f2fs_readonly(sbi->sb) ? "RO" : "RW",
+			is_set_ckpt_flags(sbi, CP_DISABLED_FLAG) ?
+			"Disabled" : (f2fs_cp_error(sbi) ? "Error" : "Good"));
+		if (sbi->s_flag) {
+			seq_puts(s, "[SBI:");
+			for_each_set_bit(j, &sbi->s_flag, MAX_SBI_FLAG)
+				seq_printf(s, " %s", s_flag[j]);
+			seq_puts(s, "]\n");
+		}
+		seq_printf(s, "[SB: 1] [CP: 2] [SIT: %d] [NAT: %d] ",
+			   si->sit_area_segs, si->nat_area_segs);
+		seq_printf(s, "[SSA: %d] [MAIN: %d",
+			   si->ssa_area_segs, si->main_area_segs);
+		seq_printf(s, "(OverProv:%d Resv:%d)]\n\n",
+			   si->overp_segs, si->rsvd_segs);
+		seq_printf(s, "Current Time Sec: %llu / Mounted Time Sec: %llu\n\n",
+					ktime_get_boottime_seconds(),
+					SIT_I(sbi)->mounted_time);
+
+		seq_puts(s, "Policy:\n");
+		seq_puts(s, "  - IPU: [");
+		if (IS_F2FS_IPU_DISABLE(sbi)) {
+			seq_puts(s, " DISABLE");
+		} else {
+			unsigned long policy = SM_I(sbi)->ipu_policy;
+
+			for_each_set_bit(j, &policy, F2FS_IPU_MAX)
+				seq_printf(s, " %s", ipu_mode_names[j]);
+		}
+		seq_puts(s, " ]\n\n");
+
+		if (test_opt(sbi, DISCARD))
+			seq_printf(s, "Utilization: %u%% (%u valid blocks, %u discard blocks)\n",
+				si->utilization, si->valid_count, si->discard_blks);
+		else
+			seq_printf(s, "Utilization: %u%% (%u valid blocks)\n",
+				si->utilization, si->valid_count);
+
+		seq_printf(s, "  - Node: %u (Inode: %u, ",
+			   si->valid_node_count, si->valid_inode_count);
+		seq_printf(s, "Other: %u)\n  - Data: %u\n",
+			   si->valid_node_count - si->valid_inode_count,
+			   si->valid_count - si->valid_node_count);
+		seq_printf(s, "  - Inline_xattr Inode: %u\n",
+			   si->inline_xattr);
+		seq_printf(s, "  - Inline_data Inode: %u\n",
+			   si->inline_inode);
+		seq_printf(s, "  - Inline_dentry Inode: %u\n",
+			   si->inline_dir);
+		seq_printf(s, "  - Compressed Inode: %u, Blocks: %llu\n",
+			   si->compr_inode, si->compr_blocks);
+		seq_printf(s, "  - Swapfile Inode: %u\n",
+			   si->swapfile_inode);
+		seq_printf(s, "  - Donate Inode: %u\n",
+			   si->ndonate_files);
+		seq_printf(s, "  - Orphan/Append/Update Inode: %u, %u, %u\n",
+			   si->orphans, si->append, si->update);
+		seq_printf(s, "\nMain area: %d segs, %d secs %d zones\n",
+			   si->main_area_segs, si->main_area_sections,
+			   si->main_area_zones);
+		seq_printf(s, "    TYPE         %8s %8s %8s %8s %10s %10s %10s\n",
+			   "blkoff", "segno", "secno", "zoneno", "dirty_seg", "full_seg", "valid_blk");
+		seq_printf(s, "  - COLD   data: %8d %8d %8d %8d %10u %10u %10u\n",
+			   si->blkoff[CURSEG_COLD_DATA],
+			   si->curseg[CURSEG_COLD_DATA],
+			   si->cursec[CURSEG_COLD_DATA],
+			   si->curzone[CURSEG_COLD_DATA],
+			   si->dirty_seg[CURSEG_COLD_DATA],
+			   si->full_seg[CURSEG_COLD_DATA],
+			   si->valid_blks[CURSEG_COLD_DATA]);
+		seq_printf(s, "  - WARM   data: %8d %8d %8d %8d %10u %10u %10u\n",
+			   si->blkoff[CURSEG_WARM_DATA],
+			   si->curseg[CURSEG_WARM_DATA],
+			   si->cursec[CURSEG_WARM_DATA],
+			   si->curzone[CURSEG_WARM_DATA],
+			   si->dirty_seg[CURSEG_WARM_DATA],
+			   si->full_seg[CURSEG_WARM_DATA],
+			   si->valid_blks[CURSEG_WARM_DATA]);
+		seq_printf(s, "  - HOT    data: %8d %8d %8d %8d %10u %10u %10u\n",
+			   si->blkoff[CURSEG_HOT_DATA],
+			   si->curseg[CURSEG_HOT_DATA],
+			   si->cursec[CURSEG_HOT_DATA],
+			   si->curzone[CURSEG_HOT_DATA],
+			   si->dirty_seg[CURSEG_HOT_DATA],
+			   si->full_seg[CURSEG_HOT_DATA],
+			   si->valid_blks[CURSEG_HOT_DATA]);
+		seq_printf(s, "  - Dir   dnode: %8d %8d %8d %8d %10u %10u %10u\n",
+			   si->blkoff[CURSEG_HOT_NODE],
+			   si->curseg[CURSEG_HOT_NODE],
+			   si->cursec[CURSEG_HOT_NODE],
+			   si->curzone[CURSEG_HOT_NODE],
+			   si->dirty_seg[CURSEG_HOT_NODE],
+			   si->full_seg[CURSEG_HOT_NODE],
+			   si->valid_blks[CURSEG_HOT_NODE]);
+		seq_printf(s, "  - File  dnode: %8d %8d %8d %8d %10u %10u %10u\n",
+			   si->blkoff[CURSEG_WARM_NODE],
+			   si->curseg[CURSEG_WARM_NODE],
+			   si->cursec[CURSEG_WARM_NODE],
+			   si->curzone[CURSEG_WARM_NODE],
+			   si->dirty_seg[CURSEG_WARM_NODE],
+			   si->full_seg[CURSEG_WARM_NODE],
+			   si->valid_blks[CURSEG_WARM_NODE]);
+		seq_printf(s, "  - Indir nodes: %8d %8d %8d %8d %10u %10u %10u\n",
+			   si->blkoff[CURSEG_COLD_NODE],
+			   si->curseg[CURSEG_COLD_NODE],
+			   si->cursec[CURSEG_COLD_NODE],
+			   si->curzone[CURSEG_COLD_NODE],
+			   si->dirty_seg[CURSEG_COLD_NODE],
+			   si->full_seg[CURSEG_COLD_NODE],
+			   si->valid_blks[CURSEG_COLD_NODE]);
+		seq_printf(s, "  - Pinned file: %8d %8d %8d %8d\n",
+			   si->blkoff[CURSEG_COLD_DATA_PINNED],
+			   si->curseg[CURSEG_COLD_DATA_PINNED],
+			   si->cursec[CURSEG_COLD_DATA_PINNED],
+			   si->curzone[CURSEG_COLD_DATA_PINNED]);
+		seq_printf(s, "  - ATGC   data: %8d %8d %8d %8d\n",
+			   si->blkoff[CURSEG_ALL_DATA_ATGC],
+			   si->curseg[CURSEG_ALL_DATA_ATGC],
+			   si->cursec[CURSEG_ALL_DATA_ATGC],
+			   si->curzone[CURSEG_ALL_DATA_ATGC]);
+		seq_printf(s, "\n  - Valid: %d\n  - Dirty: %d\n",
+			   si->main_area_segs - si->dirty_count -
+			   si->prefree_count - si->free_segs,
+			   si->dirty_count);
+		seq_printf(s, "  - Prefree: %d\n  - Free: %d (%d)\n\n",
+			   si->prefree_count, si->free_segs, si->free_secs);
+		if (f2fs_is_multi_device(sbi)) {
+			seq_puts(s, "Multidevice stats:\n");
+			seq_printf(s, "  [seg:   %8s %8s %8s %8s %8s]",
+					"inuse", "dirty", "full", "free", "prefree");
+			if (__is_large_section(sbi))
+				seq_printf(s, " [sec:   %8s %8s %8s %8s %8s]\n",
+					"inuse", "dirty", "full", "free", "prefree");
+			else
+				seq_puts(s, "\n");
+
+			for (i = 0; i < sbi->s_ndevs; i++) {
+				seq_printf(s, "  #%-2d     %8u %8u %8u %8u %8u", i,
+					si->dev_stats[i].devstats[0][DEVSTAT_INUSE],
+					si->dev_stats[i].devstats[0][DEVSTAT_DIRTY],
+					si->dev_stats[i].devstats[0][DEVSTAT_FULL],
+					si->dev_stats[i].devstats[0][DEVSTAT_FREE],
+					si->dev_stats[i].devstats[0][DEVSTAT_PREFREE]);
+				if (!__is_large_section(sbi)) {
+					seq_puts(s, "\n");
+					continue;
+				}
+				seq_printf(s, "          %8u %8u %8u %8u %8u\n",
+					si->dev_stats[i].devstats[1][DEVSTAT_INUSE],
+					si->dev_stats[i].devstats[1][DEVSTAT_DIRTY],
+					si->dev_stats[i].devstats[1][DEVSTAT_FULL],
+					si->dev_stats[i].devstats[1][DEVSTAT_FREE],
+					si->dev_stats[i].devstats[1][DEVSTAT_PREFREE]);
+			}
+			seq_puts(s, "\n");
+		}
+		seq_printf(s, "CP calls: %d (BG: %d)\n",
+			   si->cp_call_count[TOTAL_CALL],
+			   si->cp_call_count[BACKGROUND]);
+		seq_printf(s, "CP count: %d\n", si->cp_count);
+		seq_printf(s, "  - cp blocks : %u\n", si->meta_count[META_CP]);
+		seq_printf(s, "  - sit blocks : %u\n",
+				si->meta_count[META_SIT]);
+		seq_printf(s, "  - nat blocks : %u\n",
+				si->meta_count[META_NAT]);
+		seq_printf(s, "  - ssa blocks : %u\n",
+				si->meta_count[META_SSA]);
+		seq_puts(s, "CP merge:\n");
+		seq_printf(s, "  - Queued : %4d\n", si->nr_queued_ckpt);
+		seq_printf(s, "  - Issued : %4d\n", si->nr_issued_ckpt);
+		seq_printf(s, "  - Total : %4d\n", si->nr_total_ckpt);
+		seq_printf(s, "  - Cur time : %4d(ms)\n", si->cur_ckpt_time);
+		seq_printf(s, "  - Peak time : %4d(ms)\n", si->peak_ckpt_time);
+		seq_printf(s, "GC calls: %d (gc_thread: %d)\n",
+			   si->gc_call_count[BACKGROUND] +
+			   si->gc_call_count[FOREGROUND],
+			   si->gc_call_count[BACKGROUND]);
+		if (__is_large_section(sbi)) {
+			seq_printf(s, "  - data sections : %d (BG: %d)\n",
+					si->gc_secs[DATA][BG_GC] + si->gc_secs[DATA][FG_GC],
+					si->gc_secs[DATA][BG_GC]);
+			seq_printf(s, "  - node sections : %d (BG: %d)\n",
+					si->gc_secs[NODE][BG_GC] + si->gc_secs[NODE][FG_GC],
+					si->gc_secs[NODE][BG_GC]);
+		}
+		seq_printf(s, "  - data segments : %d (BG: %d)\n",
+				si->gc_segs[DATA][BG_GC] + si->gc_segs[DATA][FG_GC],
+				si->gc_segs[DATA][BG_GC]);
+		seq_printf(s, "  - node segments : %d (BG: %d)\n",
+				si->gc_segs[NODE][BG_GC] + si->gc_segs[NODE][FG_GC],
+				si->gc_segs[NODE][BG_GC]);
+		seq_puts(s, "  - Reclaimed segs :\n");
+		seq_printf(s, "    - Normal : %d\n", sbi->gc_reclaimed_segs[GC_NORMAL]);
+		seq_printf(s, "    - Idle CB : %d\n", sbi->gc_reclaimed_segs[GC_IDLE_CB]);
+		seq_printf(s, "    - Idle Greedy : %d\n",
+				sbi->gc_reclaimed_segs[GC_IDLE_GREEDY]);
+		seq_printf(s, "    - Idle AT : %d\n", sbi->gc_reclaimed_segs[GC_IDLE_AT]);
+		seq_printf(s, "    - Urgent High : %d\n",
+				sbi->gc_reclaimed_segs[GC_URGENT_HIGH]);
+		seq_printf(s, "    - Urgent Mid : %d\n", sbi->gc_reclaimed_segs[GC_URGENT_MID]);
+		seq_printf(s, "    - Urgent Low : %d\n", sbi->gc_reclaimed_segs[GC_URGENT_LOW]);
+		seq_printf(s, "Try to move %d blocks (BG: %d)\n", si->tot_blks,
+				si->bg_data_blks + si->bg_node_blks);
+		seq_printf(s, "  - data blocks : %d (%d)\n", si->data_blks,
+				si->bg_data_blks);
+		seq_printf(s, "  - node blocks : %d (%d)\n", si->node_blks,
+				si->bg_node_blks);
+		seq_printf(s, "BG skip : IO: %u, Other: %u\n",
+				si->io_skip_bggc, si->other_skip_bggc);
+		seq_printf(s, "defrag blocks : %u\n", si->defrag_blks);
+		seq_puts(s, "\nExtent Cache (Read):\n");
+		seq_printf(s, "  - Hit Count: L1-1:%llu L1-2:%llu L2:%llu\n",
+				si->hit_largest, si->hit_cached[EX_READ],
+				si->hit_rbtree[EX_READ]);
+		seq_printf(s, "  - Hit Ratio: %llu%% (%llu / %llu)\n",
+				!si->total_ext[EX_READ] ? 0 :
+				div64_u64(si->hit_total[EX_READ] * 100,
+				si->total_ext[EX_READ]),
+				si->hit_total[EX_READ], si->total_ext[EX_READ]);
+		seq_printf(s, "  - Inner Struct Count: tree: %d(%d), node: %d\n",
+				si->ext_tree[EX_READ], si->zombie_tree[EX_READ],
+				si->ext_node[EX_READ]);
+		seq_puts(s, "\nExtent Cache (Block Age):\n");
+		seq_printf(s, "  - Allocated Data Blocks: %llu\n",
+				si->allocated_data_blocks);
+		seq_printf(s, "  - Hit Count: L1:%llu L2:%llu\n",
+				si->hit_cached[EX_BLOCK_AGE],
+				si->hit_rbtree[EX_BLOCK_AGE]);
+		seq_printf(s, "  - Hit Ratio: %llu%% (%llu / %llu)\n",
+				!si->total_ext[EX_BLOCK_AGE] ? 0 :
+				div64_u64(si->hit_total[EX_BLOCK_AGE] * 100,
+				si->total_ext[EX_BLOCK_AGE]),
+				si->hit_total[EX_BLOCK_AGE],
+				si->total_ext[EX_BLOCK_AGE]);
+		seq_printf(s, "  - Inner Struct Count: tree: %d(%d), node: %d\n",
+				si->ext_tree[EX_BLOCK_AGE],
+				si->zombie_tree[EX_BLOCK_AGE],
+				si->ext_node[EX_BLOCK_AGE]);
+		seq_puts(s, "\nBalancing F2FS Async:\n");
+		seq_printf(s, "  - DIO (R: %4d, W: %4d)\n",
+			   si->nr_dio_read, si->nr_dio_write);
+		seq_printf(s, "  - IO_R (Data: %4d, Node: %4d, Meta: %4d\n",
+			   si->nr_rd_data, si->nr_rd_node, si->nr_rd_meta);
+		seq_printf(s, "  - IO_W (CP: %4d, Data: %4d, Flush: (%4d %4d %4d), ",
+			   si->nr_wb_cp_data, si->nr_wb_data,
+			   si->nr_flushing, si->nr_flushed,
+			   si->flush_list_empty);
+		seq_printf(s, "Discard: (%4d %4d)) cmd: %4d undiscard:%4u\n",
+			   si->nr_discarding, si->nr_discarded,
+			   si->nr_discard_cmd, si->undiscard_blks);
+		seq_printf(s, "  - atomic IO: %4d (Max. %4d)\n",
+			   si->aw_cnt, si->max_aw_cnt);
+		seq_printf(s, "  - compress: %4d, hit:%8d\n", si->compress_pages, si->compress_page_hit);
+		seq_printf(s, "  - nodes: %4d in %4d\n",
+			   si->ndirty_node, si->node_pages);
+		seq_printf(s, "  - dents: %4d in dirs:%4d (%4d)\n",
+			   si->ndirty_dent, si->ndirty_dirs, si->ndirty_all);
+		seq_printf(s, "  - data: %4d in files:%4d\n",
+			   si->ndirty_data, si->ndirty_files);
+		seq_printf(s, "  - quota data: %4d in quota files:%4d\n",
+			   si->ndirty_qdata, si->nquota_files);
+		seq_printf(s, "  - meta: %4d in %4d\n",
+			   si->ndirty_meta, si->meta_pages);
+		seq_printf(s, "  - imeta: %4d\n",
+			   si->ndirty_imeta);
+		seq_printf(s, "  - fsync mark: %4lld\n",
+			   percpu_counter_sum_positive(
+					&sbi->rf_node_block_count));
+		seq_printf(s, "  - NATs: %9d/%9d\n  - SITs: %9d/%9d\n",
+			   si->dirty_nats, si->nats, si->dirty_sits, si->sits);
+		seq_printf(s, "  - free_nids: %9d/%9d\n  - alloc_nids: %9d\n",
+			   si->free_nids, si->avail_nids, si->alloc_nids);
+		seq_puts(s, "\nDistribution of User Blocks:");
+		seq_puts(s, " [ valid | invalid | free ]\n");
+		seq_puts(s, "  [");
+
+		for (j = 0; j < si->util_valid; j++)
+			seq_putc(s, '-');
+		seq_putc(s, '|');
+
+		for (j = 0; j < si->util_invalid; j++)
+			seq_putc(s, '-');
+		seq_putc(s, '|');
+
+		for (j = 0; j < si->util_free; j++)
+			seq_putc(s, '-');
+		seq_puts(s, "]\n\n");
+		seq_printf(s, "IPU: %u blocks\n", si->inplace_count);
+		seq_printf(s, "SSR: %u blocks in %u segments\n",
+			   si->block_count[SSR], si->segment_count[SSR]);
+		seq_printf(s, "LFS: %u blocks in %u segments\n",
+			   si->block_count[LFS], si->segment_count[LFS]);
+
+		/* segment usage info */
+		f2fs_update_sit_info(sbi);
+		seq_printf(s, "\nBDF: %u, avg. vblocks: %u\n",
+			   si->bimodal, si->avg_vblocks);
+
+		/* memory footprint */
+		update_mem_info(sbi);
+		seq_printf(s, "\nMemory: %llu KB\n",
+			(si->base_mem + si->cache_mem + si->page_mem) >> 10);
+		seq_printf(s, "  - static: %llu KB\n",
+				si->base_mem >> 10);
+		seq_printf(s, "  - cached all: %llu KB\n",
+				si->cache_mem >> 10);
+		seq_printf(s, "  - read extent cache: %llu KB\n",
+				si->ext_mem[EX_READ] >> 10);
+		seq_printf(s, "  - block age extent cache: %llu KB\n",
+				si->ext_mem[EX_BLOCK_AGE] >> 10);
+		seq_printf(s, "  - paged : %llu KB\n",
+				si->page_mem >> 10);
+	}
+	spin_unlock(&f2fs_stat_lock);
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(stat);
+#endif
+
+int f2fs_build_stats(struct f2fs_sb_info *sbi)
+{
+	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
+	struct f2fs_stat_info *si;
+	struct f2fs_dev_stats *dev_stats;
+	int i;
+
+	si = f2fs_kzalloc(sbi, sizeof(struct f2fs_stat_info), GFP_KERNEL);
+	if (!si)
+		return -ENOMEM;
+
+	dev_stats = f2fs_kzalloc(sbi, sizeof(struct f2fs_dev_stats) *
+						sbi->s_ndevs, GFP_KERNEL);
+	if (!dev_stats) {
+		kfree(si);
+		return -ENOMEM;
+	}
+
+	si->dev_stats = dev_stats;
+
+	si->all_area_segs = le32_to_cpu(raw_super->segment_count);
+	si->sit_area_segs = le32_to_cpu(raw_super->segment_count_sit);
+	si->nat_area_segs = le32_to_cpu(raw_super->segment_count_nat);
+	si->ssa_area_segs = le32_to_cpu(raw_super->segment_count_ssa);
+	si->main_area_segs = le32_to_cpu(raw_super->segment_count_main);
+	si->main_area_sections = le32_to_cpu(raw_super->section_count);
+	si->main_area_zones = si->main_area_sections /
+				le32_to_cpu(raw_super->secs_per_zone);
+	si->sbi = sbi;
+	sbi->stat_info = si;
+
+	/* general extent cache stats */
+	for (i = 0; i < NR_EXTENT_CACHES; i++) {
+		atomic64_set(&sbi->total_hit_ext[i], 0);
+		atomic64_set(&sbi->read_hit_rbtree[i], 0);
+		atomic64_set(&sbi->read_hit_cached[i], 0);
+	}
+
+	/* read extent_cache only */
+	atomic64_set(&sbi->read_hit_largest, 0);
+
+	atomic_set(&sbi->inline_xattr, 0);
+	atomic_set(&sbi->inline_inode, 0);
+	atomic_set(&sbi->inline_dir, 0);
+	atomic_set(&sbi->compr_inode, 0);
+	atomic64_set(&sbi->compr_blocks, 0);
+	atomic_set(&sbi->swapfile_inode, 0);
+	atomic_set(&sbi->atomic_files, 0);
+	atomic_set(&sbi->inplace_count, 0);
+	for (i = META_CP; i < META_MAX; i++)
+		atomic_set(&sbi->meta_count[i], 0);
+	for (i = 0; i < MAX_CALL_TYPE; i++)
+		atomic_set(&sbi->cp_call_count[i], 0);
+
+	atomic_set(&sbi->max_aw_cnt, 0);
+
+	spin_lock(&f2fs_stat_lock);
+	list_add_tail(&si->stat_list, &f2fs_stat_list);
+	spin_unlock(&f2fs_stat_lock);
+
+	return 0;
+}
+
+void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+
+	spin_lock(&f2fs_stat_lock);
+	list_del(&si->stat_list);
+	spin_unlock(&f2fs_stat_lock);
+
+	kfree(si->dev_stats);
+	kfree(si);
+}
+
+void __init f2fs_create_root_stats(void)
+{
+#ifdef CONFIG_DEBUG_FS
+	f2fs_debugfs_root = debugfs_create_dir("f2fs", NULL);
+
+	debugfs_create_file("status", 0444, f2fs_debugfs_root, NULL,
+			    &stat_fops);
+#endif
+}
+
+void f2fs_destroy_root_stats(void)
+{
+#ifdef CONFIG_DEBUG_FS
+	debugfs_remove_recursive(f2fs_debugfs_root);
+	f2fs_debugfs_root = NULL;
+#endif
+}