f2fs: add superblock and major in-memory structure

This adds the following major in-memory structures in f2fs.

- f2fs_sb_info:
  contains f2fs-specific information, two special inode pointers for node and
  meta address spaces, and orphan inode management.

- f2fs_inode_info:
  contains vfs_inode and other fs-specific information.

- f2fs_nm_info:
  contains node manager information such as NAT entry cache, free nid list,
  and NAT page management.

- f2fs_node_info:
  represents a node as node id, inode number, block address, and its version.

- f2fs_sm_info:
  contains segment manager information such as SIT entry cache, free segment
  map, current active logs, dirty segment management, and segment utilization.
  The specific structures are sit_info, free_segmap_info, dirty_seglist_info,
  curseg_info.

In addition, add F2FS_SUPER_MAGIC in magic.h.

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

1 files changed, 1062 insertions, 0 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
new file mode 100644
index 000000000000..7aa70b54172d
--- /dev/null
+++ b/fs/f2fs/f2fs.h
@@ -0,0 +1,1062 @@
+/**
+ * fs/f2fs/f2fs.h
+ *
+ * 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.
+ */
+#ifndef _LINUX_F2FS_H
+#define _LINUX_F2FS_H
+
+#include <linux/types.h>
+#include <linux/page-flags.h>
+#include <linux/buffer_head.h>
+#include <linux/version.h>
+#include <linux/slab.h>
+#include <linux/crc32.h>
+#include <linux/magic.h>
+
+/*
+ * For mount options
+ */
+#define F2FS_MOUNT_BG_GC                0x00000001
+#define F2FS_MOUNT_DISABLE_ROLL_FORWARD 0x00000002
+#define F2FS_MOUNT_DISCARD              0x00000004
+#define F2FS_MOUNT_NOHEAP               0x00000008
+#define F2FS_MOUNT_XATTR_USER           0x00000010
+#define F2FS_MOUNT_POSIX_ACL            0x00000020
+#define F2FS_MOUNT_DISABLE_EXT_IDENTIFY 0x00000040
+
+#define clear_opt(sbi, option)  (sbi->mount_opt.opt &= ~F2FS_MOUNT_##option)
+#define set_opt(sbi, option)    (sbi->mount_opt.opt |= F2FS_MOUNT_##option)
+#define test_opt(sbi, option)   (sbi->mount_opt.opt & F2FS_MOUNT_##option)
+
+#define ver_after(a, b) (typecheck(unsigned long long, a) &&            \
+                typecheck(unsigned long long, b) &&                     \
+                ((long long)((a) - (b)) > 0))
+
+typedef u64 block_t;
+typedef u32 nid_t;
+
+struct f2fs_mount_info {
+        unsigned int    opt;
+};
+
+static inline __u32 f2fs_crc32(void *buff, size_t len)
+{
+        return crc32_le(F2FS_SUPER_MAGIC, buff, len);
+}
+
+static inline bool f2fs_crc_valid(__u32 blk_crc, void *buff, size_t buff_size)
+{
+        return f2fs_crc32(buff, buff_size) == blk_crc;
+}
+
+/*
+ * For checkpoint manager
+ */
+enum {
+        NAT_BITMAP,
+        SIT_BITMAP
+};
+
+/* for the list of orphan inodes */
+struct orphan_inode_entry {
+        struct list_head list;  /* list head */
+        nid_t ino;              /* inode number */
+};
+
+/* for the list of directory inodes */
+struct dir_inode_entry {
+        struct list_head list;  /* list head */
+        struct inode *inode;    /* vfs inode pointer */
+};
+
+/* for the list of fsync inodes, used only during recovery */
+struct fsync_inode_entry {
+        struct list_head list;  /* list head */
+        struct inode *inode;    /* vfs inode pointer */
+        block_t blkaddr;        /* block address locating the last inode */
+};
+
+#define nats_in_cursum(sum)             (le16_to_cpu(sum->n_nats))
+#define sits_in_cursum(sum)             (le16_to_cpu(sum->n_sits))
+
+#define nat_in_journal(sum, i)          (sum->nat_j.entries[i].ne)
+#define nid_in_journal(sum, i)          (sum->nat_j.entries[i].nid)
+#define sit_in_journal(sum, i)          (sum->sit_j.entries[i].se)
+#define segno_in_journal(sum, i)        (sum->sit_j.entries[i].segno)
+
+static inline int update_nats_in_cursum(struct f2fs_summary_block *rs, int i)
+{
+        int before = nats_in_cursum(rs);
+        rs->n_nats = cpu_to_le16(before + i);
+        return before;
+}
+
+static inline int update_sits_in_cursum(struct f2fs_summary_block *rs, int i)
+{
+        int before = sits_in_cursum(rs);
+        rs->n_sits = cpu_to_le16(before + i);
+        return before;
+}
+
+/*
+ * For INODE and NODE manager
+ */
+#define XATTR_NODE_OFFSET       (-1)    /*
+                                         * store xattrs to one node block per
+                                         * file keeping -1 as its node offset to
+                                         * distinguish from index node blocks.
+                                         */
+#define RDONLY_NODE             1       /*
+                                         * specify a read-only mode when getting
+                                         * a node block. 0 is read-write mode.
+                                         * used by get_dnode_of_data().
+                                         */
+#define F2FS_LINK_MAX           32000   /* maximum link count per file */
+
+/* for in-memory extent cache entry */
+struct extent_info {
+        rwlock_t ext_lock;      /* rwlock for consistency */
+        unsigned int fofs;      /* start offset in a file */
+        u32 blk_addr;           /* start block address of the extent */
+        unsigned int len;       /* lenth of the extent */
+};
+
+/*
+ * i_advise uses FADVISE_XXX_BIT. We can add additional hints later.
+ */
+#define FADVISE_COLD_BIT        0x01
+
+struct f2fs_inode_info {
+        struct inode vfs_inode;         /* serve a vfs inode */
+        unsigned long i_flags;          /* keep an inode flags for ioctl */
+        unsigned char i_advise;         /* use to give file attribute hints */
+        unsigned int i_current_depth;   /* use only in directory structure */
+        umode_t i_acl_mode;             /* keep file acl mode temporarily */
+
+        /* Use below internally in f2fs*/
+        unsigned long flags;            /* use to pass per-file flags */
+        unsigned long long data_version;/* lastes version of data for fsync */
+        atomic_t dirty_dents;           /* # of dirty dentry pages */
+        f2fs_hash_t chash;              /* hash value of given file name */
+        unsigned int clevel;            /* maximum level of given file name */
+        nid_t i_xattr_nid;              /* node id that contains xattrs */
+        struct extent_info ext;         /* in-memory extent cache entry */
+};
+
+static inline void get_extent_info(struct extent_info *ext,
+                                        struct f2fs_extent i_ext)
+{
+        write_lock(&ext->ext_lock);
+        ext->fofs = le32_to_cpu(i_ext.fofs);
+        ext->blk_addr = le32_to_cpu(i_ext.blk_addr);
+        ext->len = le32_to_cpu(i_ext.len);
+        write_unlock(&ext->ext_lock);
+}
+
+static inline void set_raw_extent(struct extent_info *ext,
+                                        struct f2fs_extent *i_ext)
+{
+        read_lock(&ext->ext_lock);
+        i_ext->fofs = cpu_to_le32(ext->fofs);
+        i_ext->blk_addr = cpu_to_le32(ext->blk_addr);
+        i_ext->len = cpu_to_le32(ext->len);
+        read_unlock(&ext->ext_lock);
+}
+
+struct f2fs_nm_info {
+        block_t nat_blkaddr;            /* base disk address of NAT */
+        nid_t max_nid;                  /* maximum possible node ids */
+        nid_t init_scan_nid;            /* the first nid to be scanned */
+        nid_t next_scan_nid;            /* the next nid to be scanned */
+
+        /* NAT cache management */
+        struct radix_tree_root nat_root;/* root of the nat entry cache */
+        rwlock_t nat_tree_lock;         /* protect nat_tree_lock */
+        unsigned int nat_cnt;           /* the # of cached nat entries */
+        struct list_head nat_entries;   /* cached nat entry list (clean) */
+        struct list_head dirty_nat_entries; /* cached nat entry list (dirty) */
+
+        /* free node ids management */
+        struct list_head free_nid_list; /* a list for free nids */
+        spinlock_t free_nid_list_lock;  /* protect free nid list */
+        unsigned int fcnt;              /* the number of free node id */
+        struct mutex build_lock;        /* lock for build free nids */
+
+        /* for checkpoint */
+        char *nat_bitmap;               /* NAT bitmap pointer */
+        int bitmap_size;                /* bitmap size */
+};
+
+/*
+ * this structure is used as one of function parameters.
+ * all the information are dedicated to a given direct node block determined
+ * by the data offset in a file.
+ */
+struct dnode_of_data {
+        struct inode *inode;            /* vfs inode pointer */
+        struct page *inode_page;        /* its inode page, NULL is possible */
+        struct page *node_page;         /* cached direct node page */
+        nid_t nid;                      /* node id of the direct node block */
+        unsigned int ofs_in_node;       /* data offset in the node page */
+        bool inode_page_locked;         /* inode page is locked or not */
+        block_t data_blkaddr;           /* block address of the node block */
+};
+
+static inline void set_new_dnode(struct dnode_of_data *dn, struct inode *inode,
+                struct page *ipage, struct page *npage, nid_t nid)
+{
+        dn->inode = inode;
+        dn->inode_page = ipage;
+        dn->node_page = npage;
+        dn->nid = nid;
+        dn->inode_page_locked = 0;
+}
+
+/*
+ * For SIT manager
+ *
+ * By default, there are 6 active log areas across the whole main area.
+ * When considering hot and cold data separation to reduce cleaning overhead,
+ * we split 3 for data logs and 3 for node logs as hot, warm, and cold types,
+ * respectively.
+ * In the current design, you should not change the numbers intentionally.
+ * Instead, as a mount option such as active_logs=x, you can use 2, 4, and 6
+ * logs individually according to the underlying devices. (default: 6)
+ * Just in case, on-disk layout covers maximum 16 logs that consist of 8 for
+ * data and 8 for node logs.
+ */
+#define NR_CURSEG_DATA_TYPE     (3)
+#define NR_CURSEG_NODE_TYPE     (3)
+#define NR_CURSEG_TYPE  (NR_CURSEG_DATA_TYPE + NR_CURSEG_NODE_TYPE)
+
+enum {
+        CURSEG_HOT_DATA = 0,    /* directory entry blocks */
+        CURSEG_WARM_DATA,       /* data blocks */
+        CURSEG_COLD_DATA,       /* multimedia or GCed data blocks */
+        CURSEG_HOT_NODE,        /* direct node blocks of directory files */
+        CURSEG_WARM_NODE,       /* direct node blocks of normal files */
+        CURSEG_COLD_NODE,       /* indirect node blocks */
+        NO_CHECK_TYPE
+};
+
+struct f2fs_sm_info {
+        struct sit_info *sit_info;              /* whole segment information */
+        struct free_segmap_info *free_info;     /* free segment information */
+        struct dirty_seglist_info *dirty_info;  /* dirty segment information */
+        struct curseg_info *curseg_array;       /* active segment information */
+
+        struct list_head wblist_head;   /* list of under-writeback pages */
+        spinlock_t wblist_lock;         /* lock for checkpoint */
+
+        block_t seg0_blkaddr;           /* block address of 0'th segment */
+        block_t main_blkaddr;           /* start block address of main area */
+        block_t ssa_blkaddr;            /* start block address of SSA area */
+
+        unsigned int segment_count;     /* total # of segments */
+        unsigned int main_segments;     /* # of segments in main area */
+        unsigned int reserved_segments; /* # of reserved segments */
+        unsigned int ovp_segments;      /* # of overprovision segments */
+};
+
+/*
+ * For directory operation
+ */
+#define NODE_DIR1_BLOCK         (ADDRS_PER_INODE + 1)
+#define NODE_DIR2_BLOCK         (ADDRS_PER_INODE + 2)
+#define NODE_IND1_BLOCK         (ADDRS_PER_INODE + 3)
+#define NODE_IND2_BLOCK         (ADDRS_PER_INODE + 4)
+#define NODE_DIND_BLOCK         (ADDRS_PER_INODE + 5)
+
+/*
+ * For superblock
+ */
+/*
+ * COUNT_TYPE for monitoring
+ *
+ * f2fs monitors the number of several block types such as on-writeback,
+ * dirty dentry blocks, dirty node blocks, and dirty meta blocks.
+ */
+enum count_type {
+        F2FS_WRITEBACK,
+        F2FS_DIRTY_DENTS,
+        F2FS_DIRTY_NODES,
+        F2FS_DIRTY_META,
+        NR_COUNT_TYPE,
+};
+
+/*
+ * FS_LOCK nesting subclasses for the lock validator:
+ *
+ * The locking order between these classes is
+ * RENAME -> DENTRY_OPS -> DATA_WRITE -> DATA_NEW
+ *    -> DATA_TRUNC -> NODE_WRITE -> NODE_NEW -> NODE_TRUNC
+ */
+enum lock_type {
+        RENAME,         /* for renaming operations */
+        DENTRY_OPS,     /* for directory operations */
+        DATA_WRITE,     /* for data write */
+        DATA_NEW,       /* for data allocation */
+        DATA_TRUNC,     /* for data truncate */
+        NODE_NEW,       /* for node allocation */
+        NODE_TRUNC,     /* for node truncate */
+        NODE_WRITE,     /* for node write */
+        NR_LOCK_TYPE,
+};
+
+/*
+ * The below are the page types of bios used in submti_bio().
+ * The available types are:
+ * DATA                 User data pages. It operates as async mode.
+ * NODE                 Node pages. It operates as async mode.
+ * META                 FS metadata pages such as SIT, NAT, CP.
+ * NR_PAGE_TYPE         The number of page types.
+ * META_FLUSH           Make sure the previous pages are written
+ *                      with waiting the bio's completion
+ * ...                  Only can be used with META.
+ */
+enum page_type {
+        DATA,
+        NODE,
+        META,
+        NR_PAGE_TYPE,
+        META_FLUSH,
+};
+
+struct f2fs_sb_info {
+        struct super_block *sb;                 /* pointer to VFS super block */
+        struct buffer_head *raw_super_buf;      /* buffer head of raw sb */
+        struct f2fs_super_block *raw_super;     /* raw super block pointer */
+        int s_dirty;                            /* dirty flag for checkpoint */
+
+        /* for node-related operations */
+        struct f2fs_nm_info *nm_info;           /* node manager */
+        struct inode *node_inode;               /* cache node blocks */
+
+        /* for segment-related operations */
+        struct f2fs_sm_info *sm_info;           /* segment manager */
+        struct bio *bio[NR_PAGE_TYPE];          /* bios to merge */
+        sector_t last_block_in_bio[NR_PAGE_TYPE];       /* last block number */
+        struct rw_semaphore bio_sem;            /* IO semaphore */
+
+        /* for checkpoint */
+        struct f2fs_checkpoint *ckpt;           /* raw checkpoint pointer */
+        struct inode *meta_inode;               /* cache meta blocks */
+        struct mutex cp_mutex;                  /* for checkpoint procedure */
+        struct mutex fs_lock[NR_LOCK_TYPE];     /* for blocking FS operations */
+        struct mutex write_inode;               /* mutex for write inode */
+        struct mutex writepages;                /* mutex for writepages() */
+        int por_doing;                          /* recovery is doing or not */
+
+        /* for orphan inode management */
+        struct list_head orphan_inode_list;     /* orphan inode list */
+        struct mutex orphan_inode_mutex;        /* for orphan inode list */
+        unsigned int n_orphans;                 /* # of orphan inodes */
+
+        /* for directory inode management */
+        struct list_head dir_inode_list;        /* dir inode list */
+        spinlock_t dir_inode_lock;              /* for dir inode list lock */
+        unsigned int n_dirty_dirs;              /* # of dir inodes */
+
+        /* basic file system units */
+        unsigned int log_sectors_per_block;     /* log2 sectors per block */
+        unsigned int log_blocksize;             /* log2 block size */
+        unsigned int blocksize;                 /* block size */
+        unsigned int root_ino_num;              /* root inode number*/
+        unsigned int node_ino_num;              /* node inode number*/
+        unsigned int meta_ino_num;              /* meta inode number*/
+        unsigned int log_blocks_per_seg;        /* log2 blocks per segment */
+        unsigned int blocks_per_seg;            /* blocks per segment */
+        unsigned int segs_per_sec;              /* segments per section */
+        unsigned int secs_per_zone;             /* sections per zone */
+        unsigned int total_sections;            /* total section count */
+        unsigned int total_node_count;          /* total node block count */
+        unsigned int total_valid_node_count;    /* valid node block count */
+        unsigned int total_valid_inode_count;   /* valid inode count */
+        int active_logs;                        /* # of active logs */
+
+        block_t user_block_count;               /* # of user blocks */
+        block_t total_valid_block_count;        /* # of valid blocks */
+        block_t alloc_valid_block_count;        /* # of allocated blocks */
+        block_t last_valid_block_count;         /* for recovery */
+        u32 s_next_generation;                  /* for NFS support */
+        atomic_t nr_pages[NR_COUNT_TYPE];       /* # of pages, see count_type */
+
+        struct f2fs_mount_info mount_opt;       /* mount options */
+
+        /* for cleaning operations */
+        struct mutex gc_mutex;                  /* mutex for GC */
+        struct f2fs_gc_kthread  *gc_thread;     /* GC thread */
+
+        /*
+         * for stat information.
+         * one is for the LFS mode, and the other is for the SSR mode.
+         */
+        struct f2fs_stat_info *stat_info;       /* FS status information */
+        unsigned int segment_count[2];          /* # of allocated segments */
+        unsigned int block_count[2];            /* # of allocated blocks */
+        unsigned int last_victim[2];            /* last victim segment # */
+        int total_hit_ext, read_hit_ext;        /* extent cache hit ratio */
+        int bg_gc;                              /* background gc calls */
+        spinlock_t stat_lock;                   /* lock for stat operations */
+};
+
+/*
+ * Inline functions
+ */
+static inline struct f2fs_inode_info *F2FS_I(struct inode *inode)
+{
+        return container_of(inode, struct f2fs_inode_info, vfs_inode);
+}
+
+static inline struct f2fs_sb_info *F2FS_SB(struct super_block *sb)
+{
+        return sb->s_fs_info;
+}
+
+static inline struct f2fs_super_block *F2FS_RAW_SUPER(struct f2fs_sb_info *sbi)
+{
+        return (struct f2fs_super_block *)(sbi->raw_super);
+}
+
+static inline struct f2fs_checkpoint *F2FS_CKPT(struct f2fs_sb_info *sbi)
+{
+        return (struct f2fs_checkpoint *)(sbi->ckpt);
+}
+
+static inline struct f2fs_nm_info *NM_I(struct f2fs_sb_info *sbi)
+{
+        return (struct f2fs_nm_info *)(sbi->nm_info);
+}
+
+static inline struct f2fs_sm_info *SM_I(struct f2fs_sb_info *sbi)
+{
+        return (struct f2fs_sm_info *)(sbi->sm_info);
+}
+
+static inline struct sit_info *SIT_I(struct f2fs_sb_info *sbi)
+{
+        return (struct sit_info *)(SM_I(sbi)->sit_info);
+}
+
+static inline struct free_segmap_info *FREE_I(struct f2fs_sb_info *sbi)
+{
+        return (struct free_segmap_info *)(SM_I(sbi)->free_info);
+}
+
+static inline struct dirty_seglist_info *DIRTY_I(struct f2fs_sb_info *sbi)
+{
+        return (struct dirty_seglist_info *)(SM_I(sbi)->dirty_info);
+}
+
+static inline void F2FS_SET_SB_DIRT(struct f2fs_sb_info *sbi)
+{
+        sbi->s_dirty = 1;
+}
+
+static inline void F2FS_RESET_SB_DIRT(struct f2fs_sb_info *sbi)
+{
+        sbi->s_dirty = 0;
+}
+
+static inline void mutex_lock_op(struct f2fs_sb_info *sbi, enum lock_type t)
+{
+        mutex_lock_nested(&sbi->fs_lock[t], t);
+}
+
+static inline void mutex_unlock_op(struct f2fs_sb_info *sbi, enum lock_type t)
+{
+        mutex_unlock(&sbi->fs_lock[t]);
+}
+
+/*
+ * Check whether the given nid is within node id range.
+ */
+static inline void check_nid_range(struct f2fs_sb_info *sbi, nid_t nid)
+{
+        BUG_ON((nid >= NM_I(sbi)->max_nid));
+}
+
+#define F2FS_DEFAULT_ALLOCATED_BLOCKS   1
+
+/*
+ * Check whether the inode has blocks or not
+ */
+static inline int F2FS_HAS_BLOCKS(struct inode *inode)
+{
+        if (F2FS_I(inode)->i_xattr_nid)
+                return (inode->i_blocks > F2FS_DEFAULT_ALLOCATED_BLOCKS + 1);
+        else
+                return (inode->i_blocks > F2FS_DEFAULT_ALLOCATED_BLOCKS);
+}
+
+static inline bool inc_valid_block_count(struct f2fs_sb_info *sbi,
+                                 struct inode *inode, blkcnt_t count)
+{
+        block_t valid_block_count;
+
+        spin_lock(&sbi->stat_lock);
+        valid_block_count =
+                sbi->total_valid_block_count + (block_t)count;
+        if (valid_block_count > sbi->user_block_count) {
+                spin_unlock(&sbi->stat_lock);
+                return false;
+        }
+        inode->i_blocks += count;
+        sbi->total_valid_block_count = valid_block_count;
+        sbi->alloc_valid_block_count += (block_t)count;
+        spin_unlock(&sbi->stat_lock);
+        return true;
+}
+
+static inline int dec_valid_block_count(struct f2fs_sb_info *sbi,
+                                                struct inode *inode,
+                                                blkcnt_t count)
+{
+        spin_lock(&sbi->stat_lock);
+        BUG_ON(sbi->total_valid_block_count < (block_t) count);
+        BUG_ON(inode->i_blocks < count);
+        inode->i_blocks -= count;
+        sbi->total_valid_block_count -= (block_t)count;
+        spin_unlock(&sbi->stat_lock);
+        return 0;
+}
+
+static inline void inc_page_count(struct f2fs_sb_info *sbi, int count_type)
+{
+        atomic_inc(&sbi->nr_pages[count_type]);
+        F2FS_SET_SB_DIRT(sbi);
+}
+
+static inline void inode_inc_dirty_dents(struct inode *inode)
+{
+        atomic_inc(&F2FS_I(inode)->dirty_dents);
+}
+
+static inline void dec_page_count(struct f2fs_sb_info *sbi, int count_type)
+{
+        atomic_dec(&sbi->nr_pages[count_type]);
+}
+
+static inline void inode_dec_dirty_dents(struct inode *inode)
+{
+        atomic_dec(&F2FS_I(inode)->dirty_dents);
+}
+
+static inline int get_pages(struct f2fs_sb_info *sbi, int count_type)
+{
+        return atomic_read(&sbi->nr_pages[count_type]);
+}
+
+static inline block_t valid_user_blocks(struct f2fs_sb_info *sbi)
+{
+        block_t ret;
+        spin_lock(&sbi->stat_lock);
+        ret = sbi->total_valid_block_count;
+        spin_unlock(&sbi->stat_lock);
+        return ret;
+}
+
+static inline unsigned long __bitmap_size(struct f2fs_sb_info *sbi, int flag)
+{
+        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
+
+        /* return NAT or SIT bitmap */
+        if (flag == NAT_BITMAP)
+                return le32_to_cpu(ckpt->nat_ver_bitmap_bytesize);
+        else if (flag == SIT_BITMAP)
+                return le32_to_cpu(ckpt->sit_ver_bitmap_bytesize);
+
+        return 0;
+}
+
+static inline void *__bitmap_ptr(struct f2fs_sb_info *sbi, int flag)
+{
+        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
+        int offset = (flag == NAT_BITMAP) ? ckpt->sit_ver_bitmap_bytesize : 0;
+        return &ckpt->sit_nat_version_bitmap + offset;
+}
+
+static inline block_t __start_cp_addr(struct f2fs_sb_info *sbi)
+{
+        block_t start_addr;
+        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
+        unsigned long long ckpt_version = le64_to_cpu(ckpt->checkpoint_ver);
+
+        start_addr = le64_to_cpu(F2FS_RAW_SUPER(sbi)->cp_blkaddr);
+
+        /*
+         * odd numbered checkpoint should at cp segment 0
+         * and even segent must be at cp segment 1
+         */
+        if (!(ckpt_version & 1))
+                start_addr += sbi->blocks_per_seg;
+
+        return start_addr;
+}
+
+static inline block_t __start_sum_addr(struct f2fs_sb_info *sbi)
+{
+        return le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_start_sum);
+}
+
+static inline bool inc_valid_node_count(struct f2fs_sb_info *sbi,
+                                                struct inode *inode,
+                                                unsigned int count)
+{
+        block_t valid_block_count;
+        unsigned int valid_node_count;
+
+        spin_lock(&sbi->stat_lock);
+
+        valid_block_count = sbi->total_valid_block_count + (block_t)count;
+        sbi->alloc_valid_block_count += (block_t)count;
+        valid_node_count = sbi->total_valid_node_count + count;
+
+        if (valid_block_count > sbi->user_block_count) {
+                spin_unlock(&sbi->stat_lock);
+                return false;
+        }
+
+        if (valid_node_count > sbi->total_node_count) {
+                spin_unlock(&sbi->stat_lock);
+                return false;
+        }
+
+        if (inode)
+                inode->i_blocks += count;
+        sbi->total_valid_node_count = valid_node_count;
+        sbi->total_valid_block_count = valid_block_count;
+        spin_unlock(&sbi->stat_lock);
+
+        return true;
+}
+
+static inline void dec_valid_node_count(struct f2fs_sb_info *sbi,
+                                                struct inode *inode,
+                                                unsigned int count)
+{
+        spin_lock(&sbi->stat_lock);
+
+        BUG_ON(sbi->total_valid_block_count < count);
+        BUG_ON(sbi->total_valid_node_count < count);
+        BUG_ON(inode->i_blocks < count);
+
+        inode->i_blocks -= count;
+        sbi->total_valid_node_count -= count;
+        sbi->total_valid_block_count -= (block_t)count;
+
+        spin_unlock(&sbi->stat_lock);
+}
+
+static inline unsigned int valid_node_count(struct f2fs_sb_info *sbi)
+{
+        unsigned int ret;
+        spin_lock(&sbi->stat_lock);
+        ret = sbi->total_valid_node_count;
+        spin_unlock(&sbi->stat_lock);
+        return ret;
+}
+
+static inline void inc_valid_inode_count(struct f2fs_sb_info *sbi)
+{
+        spin_lock(&sbi->stat_lock);
+        BUG_ON(sbi->total_valid_inode_count == sbi->total_node_count);
+        sbi->total_valid_inode_count++;
+        spin_unlock(&sbi->stat_lock);
+}
+
+static inline int dec_valid_inode_count(struct f2fs_sb_info *sbi)
+{
+        spin_lock(&sbi->stat_lock);
+        BUG_ON(!sbi->total_valid_inode_count);
+        sbi->total_valid_inode_count--;
+        spin_unlock(&sbi->stat_lock);
+        return 0;
+}
+
+static inline unsigned int valid_inode_count(struct f2fs_sb_info *sbi)
+{
+        unsigned int ret;
+        spin_lock(&sbi->stat_lock);
+        ret = sbi->total_valid_inode_count;
+        spin_unlock(&sbi->stat_lock);
+        return ret;
+}
+
+static inline void f2fs_put_page(struct page *page, int unlock)
+{
+        if (!page || IS_ERR(page))
+                return;
+
+        if (unlock) {
+                BUG_ON(!PageLocked(page));
+                unlock_page(page);
+        }
+        page_cache_release(page);
+}
+
+static inline void f2fs_put_dnode(struct dnode_of_data *dn)
+{
+        if (dn->node_page)
+                f2fs_put_page(dn->node_page, 1);
+        if (dn->inode_page && dn->node_page != dn->inode_page)
+                f2fs_put_page(dn->inode_page, 0);
+        dn->node_page = NULL;
+        dn->inode_page = NULL;
+}
+
+static inline struct kmem_cache *f2fs_kmem_cache_create(const char *name,
+                                        size_t size, void (*ctor)(void *))
+{
+        return kmem_cache_create(name, size, 0, SLAB_RECLAIM_ACCOUNT, ctor);
+}
+
+#define RAW_IS_INODE(p) ((p)->footer.nid == (p)->footer.ino)
+
+static inline bool IS_INODE(struct page *page)
+{
+        struct f2fs_node *p = (struct f2fs_node *)page_address(page);
+        return RAW_IS_INODE(p);
+}
+
+static inline __le32 *blkaddr_in_node(struct f2fs_node *node)
+{
+        return RAW_IS_INODE(node) ? node->i.i_addr : node->dn.addr;
+}
+
+static inline block_t datablock_addr(struct page *node_page,
+                unsigned int offset)
+{
+        struct f2fs_node *raw_node;
+        __le32 *addr_array;
+        raw_node = (struct f2fs_node *)page_address(node_page);
+        addr_array = blkaddr_in_node(raw_node);
+        return le32_to_cpu(addr_array[offset]);
+}
+
+static inline int f2fs_test_bit(unsigned int nr, char *addr)
+{
+        int mask;
+
+        addr += (nr >> 3);
+        mask = 1 << (7 - (nr & 0x07));
+        return mask & *addr;
+}
+
+static inline int f2fs_set_bit(unsigned int nr, char *addr)
+{
+        int mask;
+        int ret;
+
+        addr += (nr >> 3);
+        mask = 1 << (7 - (nr & 0x07));
+        ret = mask & *addr;
+        *addr |= mask;
+        return ret;
+}
+
+static inline int f2fs_clear_bit(unsigned int nr, char *addr)
+{
+        int mask;
+        int ret;
+
+        addr += (nr >> 3);
+        mask = 1 << (7 - (nr & 0x07));
+        ret = mask & *addr;
+        *addr &= ~mask;
+        return ret;
+}
+
+/* used for f2fs_inode_info->flags */
+enum {
+        FI_NEW_INODE,           /* indicate newly allocated inode */
+        FI_NEED_CP,             /* need to do checkpoint during fsync */
+        FI_INC_LINK,            /* need to increment i_nlink */
+        FI_ACL_MODE,            /* indicate acl mode */
+        FI_NO_ALLOC,            /* should not allocate any blocks */
+};
+
+static inline void set_inode_flag(struct f2fs_inode_info *fi, int flag)
+{
+        set_bit(flag, &fi->flags);
+}
+
+static inline int is_inode_flag_set(struct f2fs_inode_info *fi, int flag)
+{
+        return test_bit(flag, &fi->flags);
+}
+
+static inline void clear_inode_flag(struct f2fs_inode_info *fi, int flag)
+{
+        clear_bit(flag, &fi->flags);
+}
+
+static inline void set_acl_inode(struct f2fs_inode_info *fi, umode_t mode)
+{
+        fi->i_acl_mode = mode;
+        set_inode_flag(fi, FI_ACL_MODE);
+}
+
+static inline int cond_clear_inode_flag(struct f2fs_inode_info *fi, int flag)
+{
+        if (is_inode_flag_set(fi, FI_ACL_MODE)) {
+                clear_inode_flag(fi, FI_ACL_MODE);
+                return 1;
+        }
+        return 0;
+}
+
+/*
+ * file.c
+ */
+int f2fs_sync_file(struct file *, loff_t, loff_t, int);
+void truncate_data_blocks(struct dnode_of_data *);
+void f2fs_truncate(struct inode *);
+int f2fs_setattr(struct dentry *, struct iattr *);
+int truncate_hole(struct inode *, pgoff_t, pgoff_t);
+long f2fs_ioctl(struct file *, unsigned int, unsigned long);
+
+/*
+ * inode.c
+ */
+void f2fs_set_inode_flags(struct inode *);
+struct inode *f2fs_iget_nowait(struct super_block *, unsigned long);
+struct inode *f2fs_iget(struct super_block *, unsigned long);
+void update_inode(struct inode *, struct page *);
+int f2fs_write_inode(struct inode *, struct writeback_control *);
+void f2fs_evict_inode(struct inode *);
+
+/*
+ * namei.c
+ */
+struct dentry *f2fs_get_parent(struct dentry *child);
+
+/*
+ * dir.c
+ */
+struct f2fs_dir_entry *f2fs_find_entry(struct inode *, struct qstr *,
+                                                        struct page **);
+struct f2fs_dir_entry *f2fs_parent_dir(struct inode *, struct page **);
+ino_t f2fs_inode_by_name(struct inode *, struct qstr *);
+void f2fs_set_link(struct inode *, struct f2fs_dir_entry *,
+                                struct page *, struct inode *);
+void init_dent_inode(struct dentry *, struct page *);
+int f2fs_add_link(struct dentry *, struct inode *);
+void f2fs_delete_entry(struct f2fs_dir_entry *, struct page *, struct inode *);
+int f2fs_make_empty(struct inode *, struct inode *);
+bool f2fs_empty_dir(struct inode *);
+
+/*
+ * super.c
+ */
+int f2fs_sync_fs(struct super_block *, int);
+
+/*
+ * hash.c
+ */
+f2fs_hash_t f2fs_dentry_hash(const char *, int);
+
+/*
+ * node.c
+ */
+struct dnode_of_data;
+struct node_info;
+
+int is_checkpointed_node(struct f2fs_sb_info *, nid_t);
+void get_node_info(struct f2fs_sb_info *, nid_t, struct node_info *);
+int get_dnode_of_data(struct dnode_of_data *, pgoff_t, int);
+int truncate_inode_blocks(struct inode *, pgoff_t);
+int remove_inode_page(struct inode *);
+int new_inode_page(struct inode *, struct dentry *);
+struct page *new_node_page(struct dnode_of_data *, unsigned int);
+void ra_node_page(struct f2fs_sb_info *, nid_t);
+struct page *get_node_page(struct f2fs_sb_info *, pgoff_t);
+struct page *get_node_page_ra(struct page *, int);
+void sync_inode_page(struct dnode_of_data *);
+int sync_node_pages(struct f2fs_sb_info *, nid_t, struct writeback_control *);
+bool alloc_nid(struct f2fs_sb_info *, nid_t *);
+void alloc_nid_done(struct f2fs_sb_info *, nid_t);
+void alloc_nid_failed(struct f2fs_sb_info *, nid_t);
+void recover_node_page(struct f2fs_sb_info *, struct page *,
+                struct f2fs_summary *, struct node_info *, block_t);
+int recover_inode_page(struct f2fs_sb_info *, struct page *);
+int restore_node_summary(struct f2fs_sb_info *, unsigned int,
+                                struct f2fs_summary_block *);
+void flush_nat_entries(struct f2fs_sb_info *);
+int build_node_manager(struct f2fs_sb_info *);
+void destroy_node_manager(struct f2fs_sb_info *);
+int create_node_manager_caches(void);
+void destroy_node_manager_caches(void);
+
+/*
+ * segment.c
+ */
+void f2fs_balance_fs(struct f2fs_sb_info *);
+void invalidate_blocks(struct f2fs_sb_info *, block_t);
+void locate_dirty_segment(struct f2fs_sb_info *, unsigned int);
+void clear_prefree_segments(struct f2fs_sb_info *);
+int npages_for_summary_flush(struct f2fs_sb_info *);
+void allocate_new_segments(struct f2fs_sb_info *);
+struct page *get_sum_page(struct f2fs_sb_info *, unsigned int);
+struct bio *f2fs_bio_alloc(struct block_device *, sector_t, int, gfp_t);
+void f2fs_submit_bio(struct f2fs_sb_info *, enum page_type, bool sync);
+int write_meta_page(struct f2fs_sb_info *, struct page *,
+                                        struct writeback_control *);
+void write_node_page(struct f2fs_sb_info *, struct page *, unsigned int,
+                                        block_t, block_t *);
+void write_data_page(struct inode *, struct page *, struct dnode_of_data*,
+                                        block_t, block_t *);
+void rewrite_data_page(struct f2fs_sb_info *, struct page *, block_t);
+void recover_data_page(struct f2fs_sb_info *, struct page *,
+                                struct f2fs_summary *, block_t, block_t);
+void rewrite_node_page(struct f2fs_sb_info *, struct page *,
+                                struct f2fs_summary *, block_t, block_t);
+void write_data_summaries(struct f2fs_sb_info *, block_t);
+void write_node_summaries(struct f2fs_sb_info *, block_t);
+int lookup_journal_in_cursum(struct f2fs_summary_block *,
+                                        int, unsigned int, int);
+void flush_sit_entries(struct f2fs_sb_info *);
+int build_segment_manager(struct f2fs_sb_info *);
+void reset_victim_segmap(struct f2fs_sb_info *);
+void destroy_segment_manager(struct f2fs_sb_info *);
+
+/*
+ * checkpoint.c
+ */
+struct page *grab_meta_page(struct f2fs_sb_info *, pgoff_t);
+struct page *get_meta_page(struct f2fs_sb_info *, pgoff_t);
+long sync_meta_pages(struct f2fs_sb_info *, enum page_type, long);
+int check_orphan_space(struct f2fs_sb_info *);
+void add_orphan_inode(struct f2fs_sb_info *, nid_t);
+void remove_orphan_inode(struct f2fs_sb_info *, nid_t);
+int recover_orphan_inodes(struct f2fs_sb_info *);
+int get_valid_checkpoint(struct f2fs_sb_info *);
+void set_dirty_dir_page(struct inode *, struct page *);
+void remove_dirty_dir_inode(struct inode *);
+void sync_dirty_dir_inodes(struct f2fs_sb_info *);
+void block_operations(struct f2fs_sb_info *);
+void write_checkpoint(struct f2fs_sb_info *, bool, bool);
+void init_orphan_info(struct f2fs_sb_info *);
+int create_checkpoint_caches(void);
+void destroy_checkpoint_caches(void);
+
+/*
+ * data.c
+ */
+int reserve_new_block(struct dnode_of_data *);
+void update_extent_cache(block_t, struct dnode_of_data *);
+struct page *find_data_page(struct inode *, pgoff_t);
+struct page *get_lock_data_page(struct inode *, pgoff_t);
+struct page *get_new_data_page(struct inode *, pgoff_t, bool);
+int f2fs_readpage(struct f2fs_sb_info *, struct page *, block_t, int);
+int do_write_data_page(struct page *);
+
+/*
+ * gc.c
+ */
+int start_gc_thread(struct f2fs_sb_info *);
+void stop_gc_thread(struct f2fs_sb_info *);
+block_t start_bidx_of_node(unsigned int);
+int f2fs_gc(struct f2fs_sb_info *, int);
+void build_gc_manager(struct f2fs_sb_info *);
+int create_gc_caches(void);
+void destroy_gc_caches(void);
+
+/*
+ * recovery.c
+ */
+void recover_fsync_data(struct f2fs_sb_info *);
+bool space_for_roll_forward(struct f2fs_sb_info *);
+
+/*
+ * debug.c
+ */
+#ifdef CONFIG_F2FS_STAT_FS
+struct f2fs_stat_info {
+        struct list_head stat_list;
+        struct f2fs_sb_info *sbi;
+        struct mutex stat_lock;
+        int all_area_segs, sit_area_segs, nat_area_segs, ssa_area_segs;
+        int main_area_segs, main_area_sections, main_area_zones;
+        int hit_ext, total_ext;
+        int ndirty_node, ndirty_dent, ndirty_dirs, ndirty_meta;
+        int nats, sits, fnids;
+        int total_count, utilization;
+        int bg_gc;
+        unsigned int valid_count, valid_node_count, valid_inode_count;
+        unsigned int bimodal, avg_vblocks;
+        int util_free, util_valid, util_invalid;
+        int rsvd_segs, overp_segs;
+        int dirty_count, node_pages, meta_pages;
+        int prefree_count, call_count;
+        int tot_segs, node_segs, data_segs, free_segs, free_secs;
+        int tot_blks, data_blks, node_blks;
+        int curseg[NR_CURSEG_TYPE];
+        int cursec[NR_CURSEG_TYPE];
+        int curzone[NR_CURSEG_TYPE];
+
+        unsigned int segment_count[2];
+        unsigned int block_count[2];
+        unsigned base_mem, cache_mem;
+};
+
+#define stat_inc_call_count(si) ((si)->call_count++)
+
+#define stat_inc_seg_count(sbi, type)                                   \
+        do {                                                            \
+                struct f2fs_stat_info *si = sbi->stat_info;             \
+                (si)->tot_segs++;                                       \
+                if (type == SUM_TYPE_DATA)                              \
+                        si->data_segs++;                                \
+                else                                                    \
+                        si->node_segs++;                                \
+        } while (0)
+
+#define stat_inc_tot_blk_count(si, blks)                                \
+        (si->tot_blks += (blks))
+
+#define stat_inc_data_blk_count(sbi, blks)                              \
+        do {                                                            \
+                struct f2fs_stat_info *si = sbi->stat_info;             \
+                stat_inc_tot_blk_count(si, blks);                       \
+                si->data_blks += (blks);                                \
+        } while (0)
+
+#define stat_inc_node_blk_count(sbi, blks)                              \
+        do {                                                            \
+                struct f2fs_stat_info *si = sbi->stat_info;             \
+                stat_inc_tot_blk_count(si, blks);                       \
+                si->node_blks += (blks);                                \
+        } while (0)
+
+int f2fs_build_stats(struct f2fs_sb_info *);
+void f2fs_destroy_stats(struct f2fs_sb_info *);
+void destroy_root_stats(void);
+#else
+#define stat_inc_call_count(si)
+#define stat_inc_seg_count(si, type)
+#define stat_inc_tot_blk_count(si, blks)
+#define stat_inc_data_blk_count(si, blks)
+#define stat_inc_node_blk_count(sbi, blks)
+
+static inline int f2fs_build_stats(struct f2fs_sb_info *sbi) { return 0; }
+static inline void f2fs_destroy_stats(struct f2fs_sb_info *sbi) { }
+static inline void destroy_root_stats(void) { }
+#endif
+
+extern const struct file_operations f2fs_dir_operations;
+extern const struct file_operations f2fs_file_operations;
+extern const struct inode_operations f2fs_file_inode_operations;
+extern const struct address_space_operations f2fs_dblock_aops;
+extern const struct address_space_operations f2fs_node_aops;
+extern const struct address_space_operations f2fs_meta_aops;
+extern const struct inode_operations f2fs_dir_inode_operations;
+extern const struct inode_operations f2fs_symlink_inode_operations;
+extern const struct inode_operations f2fs_special_inode_operations;
+#endif