f2fs: add checkpoint operations

This adds functions required by the checkpoint operations.

Basically, f2fs adopts a roll-back model with checkpoint blocks written in the
CP area. The checkpoint procedure includes as follows.

- write_checkpoint()
1. block_operations() freezes VFS calls.
2. submit cached bios.
3. flush_nat_entries() writes NAT pages updated by dirty NAT entries.
4. flush_sit_entries() writes SIT pages updated by dirty SIT entries.
5. do_checkpoint() writes,
  - checkpoint block (#0)
  - orphan inode blocks
  - summary blocks made by active logs
  - checkpoint block (copy of #0)
6. unblock_opeations()

In order to provide an address space for meta pages, f2fs_sb_info has a special
inode, namely meta_inode. This patch also adds the address space operations for
meta_inode.

Signed-off-by: Chul Lee <chur.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

1 files changed, 792 insertions, 0 deletions

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
new file mode 100644
index 000000000000..ab743f92ee06
--- /dev/null
+++ b/fs/f2fs/checkpoint.c
@@ -0,0 +1,792 @@
+/**
+ * fs/f2fs/checkpoint.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/bio.h>
+#include <linux/mpage.h>
+#include <linux/writeback.h>
+#include <linux/blkdev.h>
+#include <linux/f2fs_fs.h>
+#include <linux/pagevec.h>
+#include <linux/swap.h>
+
+#include "f2fs.h"
+#include "node.h"
+#include "segment.h"
+
+static struct kmem_cache *orphan_entry_slab;
+static struct kmem_cache *inode_entry_slab;
+
+/**
+ * We guarantee no failure on the returned page.
+ */
+struct page *grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
+{
+        struct address_space *mapping = sbi->meta_inode->i_mapping;
+        struct page *page = NULL;
+repeat:
+        page = grab_cache_page(mapping, index);
+        if (!page) {
+                cond_resched();
+                goto repeat;
+        }
+
+        /* We wait writeback only inside grab_meta_page() */
+        wait_on_page_writeback(page);
+        SetPageUptodate(page);
+        return page;
+}
+
+/**
+ * We guarantee no failure on the returned page.
+ */
+struct page *get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
+{
+        struct address_space *mapping = sbi->meta_inode->i_mapping;
+        struct page *page;
+repeat:
+        page = grab_cache_page(mapping, index);
+        if (!page) {
+                cond_resched();
+                goto repeat;
+        }
+        if (f2fs_readpage(sbi, page, index, READ_SYNC)) {
+                f2fs_put_page(page, 1);
+                goto repeat;
+        }
+        mark_page_accessed(page);
+
+        /* We do not allow returning an errorneous page */
+        return page;
+}
+
+static int f2fs_write_meta_page(struct page *page,
+                                struct writeback_control *wbc)
+{
+        struct inode *inode = page->mapping->host;
+        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+        int err;
+
+        wait_on_page_writeback(page);
+
+        err = write_meta_page(sbi, page, wbc);
+        if (err) {
+                wbc->pages_skipped++;
+                set_page_dirty(page);
+        }
+
+        dec_page_count(sbi, F2FS_DIRTY_META);
+
+        /* In this case, we should not unlock this page */
+        if (err != AOP_WRITEPAGE_ACTIVATE)
+                unlock_page(page);
+        return err;
+}
+
+static int f2fs_write_meta_pages(struct address_space *mapping,
+                                struct writeback_control *wbc)
+{
+        struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
+        struct block_device *bdev = sbi->sb->s_bdev;
+        long written;
+
+        if (wbc->for_kupdate)
+                return 0;
+
+        if (get_pages(sbi, F2FS_DIRTY_META) == 0)
+                return 0;
+
+        /* if mounting is failed, skip writing node pages */
+        mutex_lock(&sbi->cp_mutex);
+        written = sync_meta_pages(sbi, META, bio_get_nr_vecs(bdev));
+        mutex_unlock(&sbi->cp_mutex);
+        wbc->nr_to_write -= written;
+        return 0;
+}
+
+long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
+                                                long nr_to_write)
+{
+        struct address_space *mapping = sbi->meta_inode->i_mapping;
+        pgoff_t index = 0, end = LONG_MAX;
+        struct pagevec pvec;
+        long nwritten = 0;
+        struct writeback_control wbc = {
+                .for_reclaim = 0,
+        };
+
+        pagevec_init(&pvec, 0);
+
+        while (index <= end) {
+                int i, nr_pages;
+                nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+                                PAGECACHE_TAG_DIRTY,
+                                min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
+                if (nr_pages == 0)
+                        break;
+
+                for (i = 0; i < nr_pages; i++) {
+                        struct page *page = pvec.pages[i];
+                        lock_page(page);
+                        BUG_ON(page->mapping != mapping);
+                        BUG_ON(!PageDirty(page));
+                        clear_page_dirty_for_io(page);
+                        f2fs_write_meta_page(page, &wbc);
+                        if (nwritten++ >= nr_to_write)
+                                break;
+                }
+                pagevec_release(&pvec);
+                cond_resched();
+        }
+
+        if (nwritten)
+                f2fs_submit_bio(sbi, type, nr_to_write == LONG_MAX);
+
+        return nwritten;
+}
+
+static int f2fs_set_meta_page_dirty(struct page *page)
+{
+        struct address_space *mapping = page->mapping;
+        struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
+
+        SetPageUptodate(page);
+        if (!PageDirty(page)) {
+                __set_page_dirty_nobuffers(page);
+                inc_page_count(sbi, F2FS_DIRTY_META);
+                F2FS_SET_SB_DIRT(sbi);
+                return 1;
+        }
+        return 0;
+}
+
+const struct address_space_operations f2fs_meta_aops = {
+        .writepage      = f2fs_write_meta_page,
+        .writepages     = f2fs_write_meta_pages,
+        .set_page_dirty = f2fs_set_meta_page_dirty,
+};
+
+int check_orphan_space(struct f2fs_sb_info *sbi)
+{
+        unsigned int max_orphans;
+        int err = 0;
+
+        /*
+         * considering 512 blocks in a segment 5 blocks are needed for cp
+         * and log segment summaries. Remaining blocks are used to keep
+         * orphan entries with the limitation one reserved segment
+         * for cp pack we can have max 1020*507 orphan entries
+         */
+        max_orphans = (sbi->blocks_per_seg - 5) * F2FS_ORPHANS_PER_BLOCK;
+        mutex_lock(&sbi->orphan_inode_mutex);
+        if (sbi->n_orphans >= max_orphans)
+                err = -ENOSPC;
+        mutex_unlock(&sbi->orphan_inode_mutex);
+        return err;
+}
+
+void add_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
+{
+        struct list_head *head, *this;
+        struct orphan_inode_entry *new = NULL, *orphan = NULL;
+
+        mutex_lock(&sbi->orphan_inode_mutex);
+        head = &sbi->orphan_inode_list;
+        list_for_each(this, head) {
+                orphan = list_entry(this, struct orphan_inode_entry, list);
+                if (orphan->ino == ino)
+                        goto out;
+                if (orphan->ino > ino)
+                        break;
+                orphan = NULL;
+        }
+retry:
+        new = kmem_cache_alloc(orphan_entry_slab, GFP_ATOMIC);
+        if (!new) {
+                cond_resched();
+                goto retry;
+        }
+        new->ino = ino;
+        INIT_LIST_HEAD(&new->list);
+
+        /* add new_oentry into list which is sorted by inode number */
+        if (orphan) {
+                struct orphan_inode_entry *prev;
+
+                /* get previous entry */
+                prev = list_entry(orphan->list.prev, typeof(*prev), list);
+                if (&prev->list != head)
+                        /* insert new orphan inode entry */
+                        list_add(&new->list, &prev->list);
+                else
+                        list_add(&new->list, head);
+        } else {
+                list_add_tail(&new->list, head);
+        }
+        sbi->n_orphans++;
+out:
+        mutex_unlock(&sbi->orphan_inode_mutex);
+}
+
+void remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
+{
+        struct list_head *this, *next, *head;
+        struct orphan_inode_entry *orphan;
+
+        mutex_lock(&sbi->orphan_inode_mutex);
+        head = &sbi->orphan_inode_list;
+        list_for_each_safe(this, next, head) {
+                orphan = list_entry(this, struct orphan_inode_entry, list);
+                if (orphan->ino == ino) {
+                        list_del(&orphan->list);
+                        kmem_cache_free(orphan_entry_slab, orphan);
+                        sbi->n_orphans--;
+                        break;
+                }
+        }
+        mutex_unlock(&sbi->orphan_inode_mutex);
+}
+
+static void recover_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
+{
+        struct inode *inode = f2fs_iget(sbi->sb, ino);
+        BUG_ON(IS_ERR(inode));
+        clear_nlink(inode);
+
+        /* truncate all the data during iput */
+        iput(inode);
+}
+
+int recover_orphan_inodes(struct f2fs_sb_info *sbi)
+{
+        block_t start_blk, orphan_blkaddr, i, j;
+
+        if (!(F2FS_CKPT(sbi)->ckpt_flags & CP_ORPHAN_PRESENT_FLAG))
+                return 0;
+
+        sbi->por_doing = 1;
+        start_blk = __start_cp_addr(sbi) + 1;
+        orphan_blkaddr = __start_sum_addr(sbi) - 1;
+
+        for (i = 0; i < orphan_blkaddr; i++) {
+                struct page *page = get_meta_page(sbi, start_blk + i);
+                struct f2fs_orphan_block *orphan_blk;
+
+                orphan_blk = (struct f2fs_orphan_block *)page_address(page);
+                for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
+                        nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
+                        recover_orphan_inode(sbi, ino);
+                }
+                f2fs_put_page(page, 1);
+        }
+        /* clear Orphan Flag */
+        F2FS_CKPT(sbi)->ckpt_flags &= (~CP_ORPHAN_PRESENT_FLAG);
+        sbi->por_doing = 0;
+        return 0;
+}
+
+static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
+{
+        struct list_head *head, *this, *next;
+        struct f2fs_orphan_block *orphan_blk = NULL;
+        struct page *page = NULL;
+        unsigned int nentries = 0;
+        unsigned short index = 1;
+        unsigned short orphan_blocks;
+
+        orphan_blocks = (unsigned short)((sbi->n_orphans +
+                (F2FS_ORPHANS_PER_BLOCK - 1)) / F2FS_ORPHANS_PER_BLOCK);
+
+        mutex_lock(&sbi->orphan_inode_mutex);
+        head = &sbi->orphan_inode_list;
+
+        /* loop for each orphan inode entry and write them in Jornal block */
+        list_for_each_safe(this, next, head) {
+                struct orphan_inode_entry *orphan;
+
+                orphan = list_entry(this, struct orphan_inode_entry, list);
+
+                if (nentries == F2FS_ORPHANS_PER_BLOCK) {
+                        /*
+                         * an orphan block is full of 1020 entries,
+                         * then we need to flush current orphan blocks
+                         * and bring another one in memory
+                         */
+                        orphan_blk->blk_addr = cpu_to_le16(index);
+                        orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
+                        orphan_blk->entry_count = cpu_to_le32(nentries);
+                        set_page_dirty(page);
+                        f2fs_put_page(page, 1);
+                        index++;
+                        start_blk++;
+                        nentries = 0;
+                        page = NULL;
+                }
+                if (page)
+                        goto page_exist;
+
+                page = grab_meta_page(sbi, start_blk);
+                orphan_blk = (struct f2fs_orphan_block *)page_address(page);
+                memset(orphan_blk, 0, sizeof(*orphan_blk));
+page_exist:
+                orphan_blk->ino[nentries++] = cpu_to_le32(orphan->ino);
+        }
+        if (!page)
+                goto end;
+
+        orphan_blk->blk_addr = cpu_to_le16(index);
+        orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
+        orphan_blk->entry_count = cpu_to_le32(nentries);
+        set_page_dirty(page);
+        f2fs_put_page(page, 1);
+end:
+        mutex_unlock(&sbi->orphan_inode_mutex);
+}
+
+static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
+                                block_t cp_addr, unsigned long long *version)
+{
+        struct page *cp_page_1, *cp_page_2 = NULL;
+        unsigned long blk_size = sbi->blocksize;
+        struct f2fs_checkpoint *cp_block;
+        unsigned long long cur_version = 0, pre_version = 0;
+        unsigned int crc = 0;
+        size_t crc_offset;
+
+        /* Read the 1st cp block in this CP pack */
+        cp_page_1 = get_meta_page(sbi, cp_addr);
+
+        /* get the version number */
+        cp_block = (struct f2fs_checkpoint *)page_address(cp_page_1);
+        crc_offset = le32_to_cpu(cp_block->checksum_offset);
+        if (crc_offset >= blk_size)
+                goto invalid_cp1;
+
+        crc = *(unsigned int *)((unsigned char *)cp_block + crc_offset);
+        if (!f2fs_crc_valid(crc, cp_block, crc_offset))
+                goto invalid_cp1;
+
+        pre_version = le64_to_cpu(cp_block->checkpoint_ver);
+
+        /* Read the 2nd cp block in this CP pack */
+        cp_addr += le64_to_cpu(cp_block->cp_pack_total_block_count) - 1;
+        cp_page_2 = get_meta_page(sbi, cp_addr);
+
+        cp_block = (struct f2fs_checkpoint *)page_address(cp_page_2);
+        crc_offset = le32_to_cpu(cp_block->checksum_offset);
+        if (crc_offset >= blk_size)
+                goto invalid_cp2;
+
+        crc = *(unsigned int *)((unsigned char *)cp_block + crc_offset);
+        if (!f2fs_crc_valid(crc, cp_block, crc_offset))
+                goto invalid_cp2;
+
+        cur_version = le64_to_cpu(cp_block->checkpoint_ver);
+
+        if (cur_version == pre_version) {
+                *version = cur_version;
+                f2fs_put_page(cp_page_2, 1);
+                return cp_page_1;
+        }
+invalid_cp2:
+        f2fs_put_page(cp_page_2, 1);
+invalid_cp1:
+        f2fs_put_page(cp_page_1, 1);
+        return NULL;
+}
+
+int get_valid_checkpoint(struct f2fs_sb_info *sbi)
+{
+        struct f2fs_checkpoint *cp_block;
+        struct f2fs_super_block *fsb = sbi->raw_super;
+        struct page *cp1, *cp2, *cur_page;
+        unsigned long blk_size = sbi->blocksize;
+        unsigned long long cp1_version = 0, cp2_version = 0;
+        unsigned long long cp_start_blk_no;
+
+        sbi->ckpt = kzalloc(blk_size, GFP_KERNEL);
+        if (!sbi->ckpt)
+                return -ENOMEM;
+        /*
+         * Finding out valid cp block involves read both
+         * sets( cp pack1 and cp pack 2)
+         */
+        cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
+        cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
+
+        /* The second checkpoint pack should start at the next segment */
+        cp_start_blk_no += 1 << le32_to_cpu(fsb->log_blocks_per_seg);
+        cp2 = validate_checkpoint(sbi, cp_start_blk_no, &cp2_version);
+
+        if (cp1 && cp2) {
+                if (ver_after(cp2_version, cp1_version))
+                        cur_page = cp2;
+                else
+                        cur_page = cp1;
+        } else if (cp1) {
+                cur_page = cp1;
+        } else if (cp2) {
+                cur_page = cp2;
+        } else {
+                goto fail_no_cp;
+        }
+
+        cp_block = (struct f2fs_checkpoint *)page_address(cur_page);
+        memcpy(sbi->ckpt, cp_block, blk_size);
+
+        f2fs_put_page(cp1, 1);
+        f2fs_put_page(cp2, 1);
+        return 0;
+
+fail_no_cp:
+        kfree(sbi->ckpt);
+        return -EINVAL;
+}
+
+void set_dirty_dir_page(struct inode *inode, struct page *page)
+{
+        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+        struct list_head *head = &sbi->dir_inode_list;
+        struct dir_inode_entry *new;
+        struct list_head *this;
+
+        if (!S_ISDIR(inode->i_mode))
+                return;
+retry:
+        new = kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
+        if (!new) {
+                cond_resched();
+                goto retry;
+        }
+        new->inode = inode;
+        INIT_LIST_HEAD(&new->list);
+
+        spin_lock(&sbi->dir_inode_lock);
+        list_for_each(this, head) {
+                struct dir_inode_entry *entry;
+                entry = list_entry(this, struct dir_inode_entry, list);
+                if (entry->inode == inode) {
+                        kmem_cache_free(inode_entry_slab, new);
+                        goto out;
+                }
+        }
+        list_add_tail(&new->list, head);
+        sbi->n_dirty_dirs++;
+
+        BUG_ON(!S_ISDIR(inode->i_mode));
+out:
+        inc_page_count(sbi, F2FS_DIRTY_DENTS);
+        inode_inc_dirty_dents(inode);
+        SetPagePrivate(page);
+
+        spin_unlock(&sbi->dir_inode_lock);
+}
+
+void remove_dirty_dir_inode(struct inode *inode)
+{
+        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+        struct list_head *head = &sbi->dir_inode_list;
+        struct list_head *this;
+
+        if (!S_ISDIR(inode->i_mode))
+                return;
+
+        spin_lock(&sbi->dir_inode_lock);
+        if (atomic_read(&F2FS_I(inode)->dirty_dents))
+                goto out;
+
+        list_for_each(this, head) {
+                struct dir_inode_entry *entry;
+                entry = list_entry(this, struct dir_inode_entry, list);
+                if (entry->inode == inode) {
+                        list_del(&entry->list);
+                        kmem_cache_free(inode_entry_slab, entry);
+                        sbi->n_dirty_dirs--;
+                        break;
+                }
+        }
+out:
+        spin_unlock(&sbi->dir_inode_lock);
+}
+
+void sync_dirty_dir_inodes(struct f2fs_sb_info *sbi)
+{
+        struct list_head *head = &sbi->dir_inode_list;
+        struct dir_inode_entry *entry;
+        struct inode *inode;
+retry:
+        spin_lock(&sbi->dir_inode_lock);
+        if (list_empty(head)) {
+                spin_unlock(&sbi->dir_inode_lock);
+                return;
+        }
+        entry = list_entry(head->next, struct dir_inode_entry, list);
+        inode = igrab(entry->inode);
+        spin_unlock(&sbi->dir_inode_lock);
+        if (inode) {
+                filemap_flush(inode->i_mapping);
+                iput(inode);
+        } else {
+                /*
+                 * We should submit bio, since it exists several
+                 * wribacking dentry pages in the freeing inode.
+                 */
+                f2fs_submit_bio(sbi, DATA, true);
+        }
+        goto retry;
+}
+
+/**
+ * Freeze all the FS-operations for checkpoint.
+ */
+void block_operations(struct f2fs_sb_info *sbi)
+{
+        int t;
+        struct writeback_control wbc = {
+                .sync_mode = WB_SYNC_ALL,
+                .nr_to_write = LONG_MAX,
+                .for_reclaim = 0,
+        };
+
+        /* Stop renaming operation */
+        mutex_lock_op(sbi, RENAME);
+        mutex_lock_op(sbi, DENTRY_OPS);
+
+retry_dents:
+        /* write all the dirty dentry pages */
+        sync_dirty_dir_inodes(sbi);
+
+        mutex_lock_op(sbi, DATA_WRITE);
+        if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
+                mutex_unlock_op(sbi, DATA_WRITE);
+                goto retry_dents;
+        }
+
+        /* block all the operations */
+        for (t = DATA_NEW; t <= NODE_TRUNC; t++)
+                mutex_lock_op(sbi, t);
+
+        mutex_lock(&sbi->write_inode);
+
+        /*
+         * POR: we should ensure that there is no dirty node pages
+         * until finishing nat/sit flush.
+         */
+retry:
+        sync_node_pages(sbi, 0, &wbc);
+
+        mutex_lock_op(sbi, NODE_WRITE);
+
+        if (get_pages(sbi, F2FS_DIRTY_NODES)) {
+                mutex_unlock_op(sbi, NODE_WRITE);
+                goto retry;
+        }
+        mutex_unlock(&sbi->write_inode);
+}
+
+static void unblock_operations(struct f2fs_sb_info *sbi)
+{
+        int t;
+        for (t = NODE_WRITE; t >= RENAME; t--)
+                mutex_unlock_op(sbi, t);
+}
+
+static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
+{
+        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
+        nid_t last_nid = 0;
+        block_t start_blk;
+        struct page *cp_page;
+        unsigned int data_sum_blocks, orphan_blocks;
+        void *kaddr;
+        __u32 crc32 = 0;
+        int i;
+
+        /* Flush all the NAT/SIT pages */
+        while (get_pages(sbi, F2FS_DIRTY_META))
+                sync_meta_pages(sbi, META, LONG_MAX);
+
+        next_free_nid(sbi, &last_nid);
+
+        /*
+         * modify checkpoint
+         * version number is already updated
+         */
+        ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi));
+        ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
+        ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
+        for (i = 0; i < 3; i++) {
+                ckpt->cur_node_segno[i] =
+                        cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
+                ckpt->cur_node_blkoff[i] =
+                        cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_NODE));
+                ckpt->alloc_type[i + CURSEG_HOT_NODE] =
+                                curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
+        }
+        for (i = 0; i < 3; i++) {
+                ckpt->cur_data_segno[i] =
+                        cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
+                ckpt->cur_data_blkoff[i] =
+                        cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_DATA));
+                ckpt->alloc_type[i + CURSEG_HOT_DATA] =
+                                curseg_alloc_type(sbi, i + CURSEG_HOT_DATA);
+        }
+
+        ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi));
+        ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi));
+        ckpt->next_free_nid = cpu_to_le32(last_nid);
+
+        /* 2 cp  + n data seg summary + orphan inode blocks */
+        data_sum_blocks = npages_for_summary_flush(sbi);
+        if (data_sum_blocks < 3)
+                ckpt->ckpt_flags |= CP_COMPACT_SUM_FLAG;
+        else
+                ckpt->ckpt_flags &= (~CP_COMPACT_SUM_FLAG);
+
+        orphan_blocks = (sbi->n_orphans + F2FS_ORPHANS_PER_BLOCK - 1)
+                                        / F2FS_ORPHANS_PER_BLOCK;
+        ckpt->cp_pack_start_sum = 1 + orphan_blocks;
+        ckpt->cp_pack_total_block_count = 2 + data_sum_blocks + orphan_blocks;
+
+        if (is_umount) {
+                ckpt->ckpt_flags |= CP_UMOUNT_FLAG;
+                ckpt->cp_pack_total_block_count += NR_CURSEG_NODE_TYPE;
+        } else {
+                ckpt->ckpt_flags &= (~CP_UMOUNT_FLAG);
+        }
+
+        if (sbi->n_orphans)
+                ckpt->ckpt_flags |= CP_ORPHAN_PRESENT_FLAG;
+        else
+                ckpt->ckpt_flags &= (~CP_ORPHAN_PRESENT_FLAG);
+
+        /* update SIT/NAT bitmap */
+        get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
+        get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
+
+        crc32 = f2fs_crc32(ckpt, le32_to_cpu(ckpt->checksum_offset));
+        *(__u32 *)((unsigned char *)ckpt +
+                                le32_to_cpu(ckpt->checksum_offset))
+                                = cpu_to_le32(crc32);
+
+        start_blk = __start_cp_addr(sbi);
+
+        /* write out checkpoint buffer at block 0 */
+        cp_page = grab_meta_page(sbi, start_blk++);
+        kaddr = page_address(cp_page);
+        memcpy(kaddr, ckpt, (1 << sbi->log_blocksize));
+        set_page_dirty(cp_page);
+        f2fs_put_page(cp_page, 1);
+
+        if (sbi->n_orphans) {
+                write_orphan_inodes(sbi, start_blk);
+                start_blk += orphan_blocks;
+        }
+
+        write_data_summaries(sbi, start_blk);
+        start_blk += data_sum_blocks;
+        if (is_umount) {
+                write_node_summaries(sbi, start_blk);
+                start_blk += NR_CURSEG_NODE_TYPE;
+        }
+
+        /* writeout checkpoint block */
+        cp_page = grab_meta_page(sbi, start_blk);
+        kaddr = page_address(cp_page);
+        memcpy(kaddr, ckpt, (1 << sbi->log_blocksize));
+        set_page_dirty(cp_page);
+        f2fs_put_page(cp_page, 1);
+
+        /* wait for previous submitted node/meta pages writeback */
+        while (get_pages(sbi, F2FS_WRITEBACK))
+                congestion_wait(BLK_RW_ASYNC, HZ / 50);
+
+        filemap_fdatawait_range(sbi->node_inode->i_mapping, 0, LONG_MAX);
+        filemap_fdatawait_range(sbi->meta_inode->i_mapping, 0, LONG_MAX);
+
+        /* update user_block_counts */
+        sbi->last_valid_block_count = sbi->total_valid_block_count;
+        sbi->alloc_valid_block_count = 0;
+
+        /* Here, we only have one bio having CP pack */
+        if (sbi->ckpt->ckpt_flags & CP_ERROR_FLAG)
+                sbi->sb->s_flags |= MS_RDONLY;
+        else
+                sync_meta_pages(sbi, META_FLUSH, LONG_MAX);
+
+        clear_prefree_segments(sbi);
+        F2FS_RESET_SB_DIRT(sbi);
+}
+
+/**
+ * We guarantee that this checkpoint procedure should not fail.
+ */
+void write_checkpoint(struct f2fs_sb_info *sbi, bool blocked, bool is_umount)
+{
+        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
+        unsigned long long ckpt_ver;
+
+        if (!blocked) {
+                mutex_lock(&sbi->cp_mutex);
+                block_operations(sbi);
+        }
+
+        f2fs_submit_bio(sbi, DATA, true);
+        f2fs_submit_bio(sbi, NODE, true);
+        f2fs_submit_bio(sbi, META, true);
+
+        /*
+         * update checkpoint pack index
+         * Increase the version number so that
+         * SIT entries and seg summaries are written at correct place
+         */
+        ckpt_ver = le64_to_cpu(ckpt->checkpoint_ver);
+        ckpt->checkpoint_ver = cpu_to_le64(++ckpt_ver);
+
+        /* write cached NAT/SIT entries to NAT/SIT area */
+        flush_nat_entries(sbi);
+        flush_sit_entries(sbi);
+
+        reset_victim_segmap(sbi);
+
+        /* unlock all the fs_lock[] in do_checkpoint() */
+        do_checkpoint(sbi, is_umount);
+
+        unblock_operations(sbi);
+        mutex_unlock(&sbi->cp_mutex);
+}
+
+void init_orphan_info(struct f2fs_sb_info *sbi)
+{
+        mutex_init(&sbi->orphan_inode_mutex);
+        INIT_LIST_HEAD(&sbi->orphan_inode_list);
+        sbi->n_orphans = 0;
+}
+
+int create_checkpoint_caches(void)
+{
+        orphan_entry_slab = f2fs_kmem_cache_create("f2fs_orphan_entry",
+                        sizeof(struct orphan_inode_entry), NULL);
+        if (unlikely(!orphan_entry_slab))
+                return -ENOMEM;
+        inode_entry_slab = f2fs_kmem_cache_create("f2fs_dirty_dir_entry",
+                        sizeof(struct dir_inode_entry), NULL);
+        if (unlikely(!inode_entry_slab)) {
+                kmem_cache_destroy(orphan_entry_slab);
+                return -ENOMEM;
+        }
+        return 0;
+}
+
+void destroy_checkpoint_caches(void)
+{
+        kmem_cache_destroy(orphan_entry_slab);
+        kmem_cache_destroy(inode_entry_slab);
+}