/*
 * 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/slab.h>
#include <linux/crc32.h>
#include <linux/magic.h>
#include <linux/kobject.h>
#include <linux/sched.h>
#include <linux/cred.h>
#include <linux/vmalloc.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/quotaops.h>
#include <crypto/hash.h>

#define __FS_HAS_ENCRYPTION IS_ENABLED(CONFIG_F2FS_FS_ENCRYPTION)
#include <linux/fscrypt.h>

#ifdef CONFIG_F2FS_CHECK_FS
#define f2fs_bug_on(sbi, condition)     BUG_ON(condition)
#else
#define f2fs_bug_on(sbi, condition)                                     \
        do {                                                            \
                if (unlikely(condition)) {                              \
                        WARN_ON(1);                                     \
                        set_sbi_flag(sbi, SBI_NEED_FSCK);               \
                }                                                       \
        } while (0)
#endif

#ifdef CONFIG_F2FS_FAULT_INJECTION
enum {
        FAULT_KMALLOC,
        FAULT_KVMALLOC,
        FAULT_PAGE_ALLOC,
        FAULT_PAGE_GET,
        FAULT_ALLOC_BIO,
        FAULT_ALLOC_NID,
        FAULT_ORPHAN,
        FAULT_BLOCK,
        FAULT_DIR_DEPTH,
        FAULT_EVICT_INODE,
        FAULT_TRUNCATE,
        FAULT_IO,
        FAULT_CHECKPOINT,
        FAULT_MAX,
};

struct f2fs_fault_info {
        atomic_t inject_ops;
        unsigned int inject_rate;
        unsigned int inject_type;
};

extern char *fault_name[FAULT_MAX];
#define IS_FAULT_SET(fi, type) ((fi)->inject_type & (1 << (type)))
#endif

/*
 * 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 F2FS_MOUNT_INLINE_XATTR         0x00000080
#define F2FS_MOUNT_INLINE_DATA          0x00000100
#define F2FS_MOUNT_INLINE_DENTRY        0x00000200
#define F2FS_MOUNT_FLUSH_MERGE          0x00000400
#define F2FS_MOUNT_NOBARRIER            0x00000800
#define F2FS_MOUNT_FASTBOOT             0x00001000
#define F2FS_MOUNT_EXTENT_CACHE         0x00002000
#define F2FS_MOUNT_FORCE_FG_GC          0x00004000
#define F2FS_MOUNT_DATA_FLUSH           0x00008000
#define F2FS_MOUNT_FAULT_INJECTION      0x00010000
#define F2FS_MOUNT_ADAPTIVE             0x00020000
#define F2FS_MOUNT_LFS                  0x00040000
#define F2FS_MOUNT_USRQUOTA             0x00080000
#define F2FS_MOUNT_GRPQUOTA             0x00100000
#define F2FS_MOUNT_PRJQUOTA             0x00200000
#define F2FS_MOUNT_QUOTA                0x00400000
#define F2FS_MOUNT_INLINE_XATTR_SIZE    0x00800000
#define F2FS_MOUNT_RESERVE_ROOT         0x01000000

#define F2FS_OPTION(sbi)        ((sbi)->mount_opt)
#define clear_opt(sbi, option)  (F2FS_OPTION(sbi).opt &= ~F2FS_MOUNT_##option)
#define set_opt(sbi, option)    (F2FS_OPTION(sbi).opt |= F2FS_MOUNT_##option)
#define test_opt(sbi, option)   (F2FS_OPTION(sbi).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 u32 block_t;    /*
                         * should not change u32, since it is the on-disk block
                         * address format, __le32.
                         */
typedef u32 nid_t;

struct f2fs_mount_info {
        unsigned int opt;
        int write_io_size_bits;         /* Write IO size bits */
        block_t root_reserved_blocks;   /* root reserved blocks */
        kuid_t s_resuid;                /* reserved blocks for uid */
        kgid_t s_resgid;                /* reserved blocks for gid */
        int active_logs;                /* # of active logs */
        int inline_xattr_size;          /* inline xattr size */
#ifdef CONFIG_F2FS_FAULT_INJECTION
        struct f2fs_fault_info fault_info;      /* For fault injection */
#endif
#ifdef CONFIG_QUOTA
        /* Names of quota files with journalled quota */
        char *s_qf_names[MAXQUOTAS];
        int s_jquota_fmt;                       /* Format of quota to use */
#endif
        /* For which write hints are passed down to block layer */
        int whint_mode;
        int alloc_mode;                 /* segment allocation policy */
        int fsync_mode;                 /* fsync policy */
        bool test_dummy_encryption;     /* test dummy encryption */
};

#define F2FS_FEATURE_ENCRYPT            0x0001
#define F2FS_FEATURE_BLKZONED           0x0002
#define F2FS_FEATURE_ATOMIC_WRITE       0x0004
#define F2FS_FEATURE_EXTRA_ATTR         0x0008
#define F2FS_FEATURE_PRJQUOTA           0x0010
#define F2FS_FEATURE_INODE_CHKSUM       0x0020
#define F2FS_FEATURE_FLEXIBLE_INLINE_XATTR      0x0040
#define F2FS_FEATURE_QUOTA_INO          0x0080
#define F2FS_FEATURE_INODE_CRTIME       0x0100
#define F2FS_FEATURE_LOST_FOUND         0x0200
#define F2FS_FEATURE_VERITY             0x0400  /* reserved */

#define F2FS_HAS_FEATURE(sb, mask)                                      \
        ((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0)
#define F2FS_SET_FEATURE(sb, mask)                                      \
        (F2FS_SB(sb)->raw_super->feature |= cpu_to_le32(mask))
#define F2FS_CLEAR_FEATURE(sb, mask)                                    \
        (F2FS_SB(sb)->raw_super->feature &= ~cpu_to_le32(mask))

/*
 * Default values for user and/or group using reserved blocks
 */
#define F2FS_DEF_RESUID         0
#define F2FS_DEF_RESGID         0

/*
 * For checkpoint manager
 */
enum {
        NAT_BITMAP,
        SIT_BITMAP
};

#define CP_UMOUNT       0x00000001
#define CP_FASTBOOT     0x00000002
#define CP_SYNC         0x00000004
#define CP_RECOVERY     0x00000008
#define CP_DISCARD      0x00000010
#define CP_TRIMMED      0x00000020

#define DEF_BATCHED_TRIM_SECTIONS       2048
#define BATCHED_TRIM_SEGMENTS(sbi)      \
                (GET_SEG_FROM_SEC(sbi, SM_I(sbi)->trim_sections))
#define BATCHED_TRIM_BLOCKS(sbi)        \
                (BATCHED_TRIM_SEGMENTS(sbi) << (sbi)->log_blocks_per_seg)
#define MAX_DISCARD_BLOCKS(sbi)         BLKS_PER_SEC(sbi)
#define DEF_MAX_DISCARD_REQUEST         8       /* issue 8 discards per round */
#define DEF_MIN_DISCARD_ISSUE_TIME      50      /* 50 ms, if exists */
#define DEF_MAX_DISCARD_ISSUE_TIME      60000   /* 60 s, if no candidates */
#define DEF_CP_INTERVAL                 60      /* 60 secs */
#define DEF_IDLE_INTERVAL               5       /* 5 secs */

struct cp_control {
        int reason;
        __u64 trim_start;
        __u64 trim_end;
        __u64 trim_minlen;
};

/*
 * For CP/NAT/SIT/SSA readahead
 */
enum {
        META_CP,
        META_NAT,
        META_SIT,
        META_SSA,
        META_POR,
};

/* for the list of ino */
enum {
        ORPHAN_INO,             /* for orphan ino list */
        APPEND_INO,             /* for append ino list */
        UPDATE_INO,             /* for update ino list */
        TRANS_DIR_INO,          /* for trasactions dir ino list */
        FLUSH_INO,              /* for multiple device flushing */
        MAX_INO_ENTRY,          /* max. list */
};

struct ino_entry {
        struct list_head list;          /* list head */
        nid_t ino;                      /* inode number */
        unsigned int dirty_device;      /* dirty device bitmap */
};

/* for the list of inodes to be GCed */
struct inode_entry {
        struct list_head list;  /* list head */
        struct inode *inode;    /* vfs inode pointer */
};

/* for the bitmap indicate blocks to be discarded */
struct discard_entry {
        struct list_head list;  /* list head */
        block_t start_blkaddr;  /* start blockaddr of current segment */
        unsigned char discard_map[SIT_VBLOCK_MAP_SIZE]; /* segment discard bitmap */
};

/* default discard granularity of inner discard thread, unit: block count */
#define DEFAULT_DISCARD_GRANULARITY             16

/* max discard pend list number */
#define MAX_PLIST_NUM           512
#define plist_idx(blk_num)      ((blk_num) >= MAX_PLIST_NUM ?           \
                                        (MAX_PLIST_NUM - 1) : (blk_num - 1))

enum {
        D_PREP,
        D_SUBMIT,
        D_DONE,
};

struct discard_info {
        block_t lstart;                 /* logical start address */
        block_t len;                    /* length */
        block_t start;                  /* actual start address in dev */
};

struct discard_cmd {
        struct rb_node rb_node;         /* rb node located in rb-tree */
        union {
                struct {
                        block_t lstart; /* logical start address */
                        block_t len;    /* length */
                        block_t start;  /* actual start address in dev */
                };
                struct discard_info di; /* discard info */

        };
        struct list_head list;          /* command list */
        struct completion wait;         /* compleation */
        struct block_device *bdev;      /* bdev */
        unsigned short ref;             /* reference count */
        unsigned char state;            /* state */
        int error;                      /* bio error */
};

enum {
        DPOLICY_BG,
        DPOLICY_FORCE,
        DPOLICY_FSTRIM,
        DPOLICY_UMOUNT,
        MAX_DPOLICY,
};

struct discard_policy {
        int type;                       /* type of discard */
        unsigned int min_interval;      /* used for candidates exist */
        unsigned int max_interval;      /* used for candidates not exist */
        unsigned int max_requests;      /* # of discards issued per round */
        unsigned int io_aware_gran;     /* minimum granularity discard not be aware of I/O */
        bool io_aware;                  /* issue discard in idle time */
        bool sync;                      /* submit discard with REQ_SYNC flag */
        unsigned int granularity;       /* discard granularity */
};

struct discard_cmd_control {
        struct task_struct *f2fs_issue_discard; /* discard thread */
        struct list_head entry_list;            /* 4KB discard entry list */
        struct list_head pend_list[MAX_PLIST_NUM];/* store pending entries */
        struct list_head wait_list;             /* store on-flushing entries */
        struct list_head fstrim_list;           /* in-flight discard from fstrim */
        wait_queue_head_t discard_wait_queue;   /* waiting queue for wake-up */
        unsigned int discard_wake;              /* to wake up discard thread */
        struct mutex cmd_lock;
        unsigned int nr_discards;               /* # of discards in the list */
        unsigned int max_discards;              /* max. discards to be issued */
        unsigned int discard_granularity;       /* discard granularity */
        unsigned int undiscard_blks;            /* # of undiscard blocks */
        atomic_t issued_discard;                /* # of issued discard */
        atomic_t issing_discard;                /* # of issing discard */
        atomic_t discard_cmd_cnt;               /* # of cached cmd count */
        struct rb_root root;                    /* root of discard rb-tree */
};

/* 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 fsync */
        block_t last_dentry;    /* block address locating the last dentry */
};

#define nats_in_cursum(jnl)             (le16_to_cpu((jnl)->n_nats))
#define sits_in_cursum(jnl)             (le16_to_cpu((jnl)->n_sits))

#define nat_in_journal(jnl, i)          ((jnl)->nat_j.entries[i].ne)
#define nid_in_journal(jnl, i)          ((jnl)->nat_j.entries[i].nid)
#define sit_in_journal(jnl, i)          ((jnl)->sit_j.entries[i].se)
#define segno_in_journal(jnl, i)        ((jnl)->sit_j.entries[i].segno)

#define MAX_NAT_JENTRIES(jnl)   (NAT_JOURNAL_ENTRIES - nats_in_cursum(jnl))
#define MAX_SIT_JENTRIES(jnl)   (SIT_JOURNAL_ENTRIES - sits_in_cursum(jnl))

static inline int update_nats_in_cursum(struct f2fs_journal *journal, int i)
{
        int before = nats_in_cursum(journal);

        journal->n_nats = cpu_to_le16(before + i);
        return before;
}

static inline int update_sits_in_cursum(struct f2fs_journal *journal, int i)
{
        int before = sits_in_cursum(journal);

        journal->n_sits = cpu_to_le16(before + i);
        return before;
}

static inline bool __has_cursum_space(struct f2fs_journal *journal,
                                                        int size, int type)
{
        if (type == NAT_JOURNAL)
                return size <= MAX_NAT_JENTRIES(journal);
        return size <= MAX_SIT_JENTRIES(journal);
}

/*
 * ioctl commands
 */
#define F2FS_IOC_GETFLAGS               FS_IOC_GETFLAGS
#define F2FS_IOC_SETFLAGS               FS_IOC_SETFLAGS
#define F2FS_IOC_GETVERSION             FS_IOC_GETVERSION

#define F2FS_IOCTL_MAGIC                0xf5
#define F2FS_IOC_START_ATOMIC_WRITE     _IO(F2FS_IOCTL_MAGIC, 1)
#define F2FS_IOC_COMMIT_ATOMIC_WRITE    _IO(F2FS_IOCTL_MAGIC, 2)
#define F2FS_IOC_START_VOLATILE_WRITE   _IO(F2FS_IOCTL_MAGIC, 3)
#define F2FS_IOC_RELEASE_VOLATILE_WRITE _IO(F2FS_IOCTL_MAGIC, 4)
#define F2FS_IOC_ABORT_VOLATILE_WRITE   _IO(F2FS_IOCTL_MAGIC, 5)
#define F2FS_IOC_GARBAGE_COLLECT        _IOW(F2FS_IOCTL_MAGIC, 6, __u32)
#define F2FS_IOC_WRITE_CHECKPOINT       _IO(F2FS_IOCTL_MAGIC, 7)
#define F2FS_IOC_DEFRAGMENT             _IOWR(F2FS_IOCTL_MAGIC, 8,      \
                                                struct f2fs_defragment)
#define F2FS_IOC_MOVE_RANGE             _IOWR(F2FS_IOCTL_MAGIC, 9,      \
                                                struct f2fs_move_range)
#define F2FS_IOC_FLUSH_DEVICE           _IOW(F2FS_IOCTL_MAGIC, 10,      \
                                                struct f2fs_flush_device)
#define F2FS_IOC_GARBAGE_COLLECT_RANGE  _IOW(F2FS_IOCTL_MAGIC, 11,      \
                                                struct f2fs_gc_range)
#define F2FS_IOC_GET_FEATURES           _IOR(F2FS_IOCTL_MAGIC, 12, __u32)
#define F2FS_IOC_SET_PIN_FILE           _IOW(F2FS_IOCTL_MAGIC, 13, __u32)
#define F2FS_IOC_GET_PIN_FILE           _IOR(F2FS_IOCTL_MAGIC, 14, __u32)
#define F2FS_IOC_PRECACHE_EXTENTS       _IO(F2FS_IOCTL_MAGIC, 15)

#define F2FS_IOC_SET_ENCRYPTION_POLICY  FS_IOC_SET_ENCRYPTION_POLICY
#define F2FS_IOC_GET_ENCRYPTION_POLICY  FS_IOC_GET_ENCRYPTION_POLICY
#define F2FS_IOC_GET_ENCRYPTION_PWSALT  FS_IOC_GET_ENCRYPTION_PWSALT

/*
 * should be same as XFS_IOC_GOINGDOWN.
 * Flags for going down operation used by FS_IOC_GOINGDOWN
 */
#define F2FS_IOC_SHUTDOWN       _IOR('X', 125, __u32)   /* Shutdown */
#define F2FS_GOING_DOWN_FULLSYNC        0x0     /* going down with full sync */
#define F2FS_GOING_DOWN_METASYNC        0x1     /* going down with metadata */
#define F2FS_GOING_DOWN_NOSYNC          0x2     /* going down */
#define F2FS_GOING_DOWN_METAFLUSH       0x3     /* going down with meta flush */

#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
/*
 * ioctl commands in 32 bit emulation
 */
#define F2FS_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
#define F2FS_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
#define F2FS_IOC32_GETVERSION           FS_IOC32_GETVERSION
#endif

#define F2FS_IOC_FSGETXATTR             FS_IOC_FSGETXATTR
#define F2FS_IOC_FSSETXATTR             FS_IOC_FSSETXATTR

struct f2fs_gc_range {
        u32 sync;
        u64 start;
        u64 len;
};

struct f2fs_defragment {
        u64 start;
        u64 len;
};

struct f2fs_move_range {
        u32 dst_fd;             /* destination fd */
        u64 pos_in;             /* start position in src_fd */
        u64 pos_out;            /* start position in dst_fd */
        u64 len;                /* size to move */
};

struct f2fs_flush_device {
        u32 dev_num;            /* device number to flush */
        u32 segments;           /* # of segments to flush */
};

/* for inline stuff */
#define DEF_INLINE_RESERVED_SIZE        1
#define DEF_MIN_INLINE_SIZE             1
static inline int get_extra_isize(struct inode *inode);
static inline int get_inline_xattr_addrs(struct inode *inode);
#define MAX_INLINE_DATA(inode)  (sizeof(__le32) *                       \
                                (CUR_ADDRS_PER_INODE(inode) -           \
                                get_inline_xattr_addrs(inode) - \
                                DEF_INLINE_RESERVED_SIZE))

/* for inline dir */
#define NR_INLINE_DENTRY(inode) (MAX_INLINE_DATA(inode) * BITS_PER_BYTE / \
                                ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
                                BITS_PER_BYTE + 1))
#define INLINE_DENTRY_BITMAP_SIZE(inode)        ((NR_INLINE_DENTRY(inode) + \
                                        BITS_PER_BYTE - 1) / BITS_PER_BYTE)
#define INLINE_RESERVED_SIZE(inode)     (MAX_INLINE_DATA(inode) - \
                                ((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
                                NR_INLINE_DENTRY(inode) + \
                                INLINE_DENTRY_BITMAP_SIZE(inode)))

/*
 * For INODE and NODE manager
 */
/* for directory operations */
struct f2fs_dentry_ptr {
        struct inode *inode;
        void *bitmap;
        struct f2fs_dir_entry *dentry;
        __u8 (*filename)[F2FS_SLOT_LEN];
        int max;
        int nr_bitmap;
};

static inline void make_dentry_ptr_block(struct inode *inode,
                struct f2fs_dentry_ptr *d, struct f2fs_dentry_block *t)
{
        d->inode = inode;
        d->max = NR_DENTRY_IN_BLOCK;
        d->nr_bitmap = SIZE_OF_DENTRY_BITMAP;
        d->bitmap = t->dentry_bitmap;
        d->dentry = t->dentry;
        d->filename = t->filename;
}

static inline void make_dentry_ptr_inline(struct inode *inode,
                                        struct f2fs_dentry_ptr *d, void *t)
{
        int entry_cnt = NR_INLINE_DENTRY(inode);
        int bitmap_size = INLINE_DENTRY_BITMAP_SIZE(inode);
        int reserved_size = INLINE_RESERVED_SIZE(inode);

        d->inode = inode;
        d->max = entry_cnt;
        d->nr_bitmap = bitmap_size;
        d->bitmap = t;
        d->dentry = t + bitmap_size + reserved_size;
        d->filename = t + bitmap_size + reserved_size +
                                        SIZE_OF_DIR_ENTRY * entry_cnt;
}

/*
 * XATTR_NODE_OFFSET stores xattrs to one node block per file keeping -1
 * as its node offset to distinguish from index node blocks.
 * But some bits are used to mark the node block.
 */
#define XATTR_NODE_OFFSET       ((((unsigned int)-1) << OFFSET_BIT_SHIFT) \
                                >> OFFSET_BIT_SHIFT)
enum {
        ALLOC_NODE,                     /* allocate a new node page if needed */
        LOOKUP_NODE,                    /* look up a node without readahead */
        LOOKUP_NODE_RA,                 /*
                                         * look up a node with readahead called
                                         * by get_data_block.
                                         */
};

#define F2FS_LINK_MAX   0xffffffff      /* maximum link count per file */

#define MAX_DIR_RA_PAGES        4       /* maximum ra pages of dir */

/* vector size for gang look-up from extent cache that consists of radix tree */
#define EXT_TREE_VEC_SIZE       64

/* for in-memory extent cache entry */
#define F2FS_MIN_EXTENT_LEN     64      /* minimum extent length */

/* number of extent info in extent cache we try to shrink */
#define EXTENT_CACHE_SHRINK_NUMBER      128

struct rb_entry {
        struct rb_node rb_node;         /* rb node located in rb-tree */
        unsigned int ofs;               /* start offset of the entry */
        unsigned int len;               /* length of the entry */
};

struct extent_info {
        unsigned int fofs;              /* start offset in a file */
        unsigned int len;               /* length of the extent */
        u32 blk;                        /* start block address of the extent */
};

struct extent_node {
        struct rb_node rb_node;
        union {
                struct {
                        unsigned int fofs;
                        unsigned int len;
                        u32 blk;
                };
                struct extent_info ei;  /* extent info */

        };
        struct list_head list;          /* node in global extent list of sbi */
        struct extent_tree *et;         /* extent tree pointer */
};

struct extent_tree {
        nid_t ino;                      /* inode number */
        struct rb_root root;            /* root of extent info rb-tree */
        struct extent_node *cached_en;  /* recently accessed extent node */
        struct extent_info largest;     /* largested extent info */
        struct list_head list;          /* to be used by sbi->zombie_list */
        rwlock_t lock;                  /* protect extent info rb-tree */
        atomic_t node_cnt;              /* # of extent node in rb-tree*/
};

/*
 * This structure is taken from ext4_map_blocks.
 *
 * Note that, however, f2fs uses NEW and MAPPED flags for f2fs_map_blocks().
 */
#define F2FS_MAP_NEW            (1 << BH_New)
#define F2FS_MAP_MAPPED         (1 << BH_Mapped)
#define F2FS_MAP_UNWRITTEN      (1 << BH_Unwritten)
#define F2FS_MAP_FLAGS          (F2FS_MAP_NEW | F2FS_MAP_MAPPED |\
                                F2FS_MAP_UNWRITTEN)

struct f2fs_map_blocks {
        block_t m_pblk;
        block_t m_lblk;
        unsigned int m_len;
        unsigned int m_flags;
        pgoff_t *m_next_pgofs;          /* point next possible non-hole pgofs */
        pgoff_t *m_next_extent;         /* point to next possible extent */
        int m_seg_type;
};

/* for flag in get_data_block */
enum {
        F2FS_GET_BLOCK_DEFAULT,
        F2FS_GET_BLOCK_FIEMAP,
        F2FS_GET_BLOCK_BMAP,
        F2FS_GET_BLOCK_PRE_DIO,
        F2FS_GET_BLOCK_PRE_AIO,
        F2FS_GET_BLOCK_PRECACHE,
};

/*
 * i_advise uses FADVISE_XXX_BIT. We can add additional hints later.
 */
#define FADVISE_COLD_BIT        0x01
#define FADVISE_LOST_PINO_BIT   0x02
#define FADVISE_ENCRYPT_BIT     0x04
#define FADVISE_ENC_NAME_BIT    0x08
#define FADVISE_KEEP_SIZE_BIT   0x10
#define FADVISE_HOT_BIT         0x20
#define FADVISE_VERITY_BIT      0x40    /* reserved */

#define file_is_cold(inode)     is_file(inode, FADVISE_COLD_BIT)
#define file_wrong_pino(inode)  is_file(inode, FADVISE_LOST_PINO_BIT)
#define file_set_cold(inode)    set_file(inode, FADVISE_COLD_BIT)
#define file_lost_pino(inode)   set_file(inode, FADVISE_LOST_PINO_BIT)
#define file_clear_cold(inode)  clear_file(inode, FADVISE_COLD_BIT)
#define file_got_pino(inode)    clear_file(inode, FADVISE_LOST_PINO_BIT)
#define file_is_encrypt(inode)  is_file(inode, FADVISE_ENCRYPT_BIT)
#define file_set_encrypt(inode) set_file(inode, FADVISE_ENCRYPT_BIT)
#define file_clear_encrypt(inode) clear_file(inode, FADVISE_ENCRYPT_BIT)
#define file_enc_name(inode)    is_file(inode, FADVISE_ENC_NAME_BIT)
#define file_set_enc_name(inode) set_file(inode, FADVISE_ENC_NAME_BIT)
#define file_keep_isize(inode)  is_file(inode, FADVISE_KEEP_SIZE_BIT)
#define file_set_keep_isize(inode) set_file(inode, FADVISE_KEEP_SIZE_BIT)
#define file_is_hot(inode)      is_file(inode, FADVISE_HOT_BIT)
#define file_set_hot(inode)     set_file(inode, FADVISE_HOT_BIT)
#define file_clear_hot(inode)   clear_file(inode, FADVISE_HOT_BIT)

#define DEF_DIR_LEVEL           0

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 char i_dir_level;      /* use for dentry level for large dir */
        union {
                unsigned int i_current_depth;   /* only for directory depth */
                unsigned short i_gc_failures;   /* only for regular file */
        };
        unsigned int i_pino;            /* parent inode number */
        umode_t i_acl_mode;             /* keep file acl mode temporarily */

        /* Use below internally in f2fs*/
        unsigned long flags;            /* use to pass per-file flags */
        struct rw_semaphore i_sem;      /* protect fi info */
        atomic_t dirty_pages;           /* # of dirty pages */
        f2fs_hash_t chash;              /* hash value of given file name */
        unsigned int clevel;            /* maximum level of given file name */
        struct task_struct *task;       /* lookup and create consistency */
        struct task_struct *cp_task;    /* separate cp/wb IO stats*/
        nid_t i_xattr_nid;              /* node id that contains xattrs */
        loff_t  last_disk_size;         /* lastly written file size */

#ifdef CONFIG_QUOTA
        struct dquot *i_dquot[MAXQUOTAS];

        /* quota space reservation, managed internally by quota code */
        qsize_t i_reserved_quota;
#endif
        struct list_head dirty_list;    /* dirty list for dirs and files */
        struct list_head gdirty_list;   /* linked in global dirty list */
        struct list_head inmem_ilist;   /* list for inmem inodes */
        struct list_head inmem_pages;   /* inmemory pages managed by f2fs */
        struct task_struct *inmem_task; /* store inmemory task */
        struct mutex inmem_lock;        /* lock for inmemory pages */
        struct extent_tree *extent_tree;        /* cached extent_tree entry */
        struct rw_semaphore dio_rwsem[2];/* avoid racing between dio and gc */
        struct rw_semaphore i_mmap_sem;
        struct rw_semaphore i_xattr_sem; /* avoid racing between reading and changing EAs */

        int i_extra_isize;              /* size of extra space located in i_addr */
        kprojid_t i_projid;             /* id for project quota */
        int i_inline_xattr_size;        /* inline xattr size */
        struct timespec i_crtime;       /* inode creation time */
        struct timespec i_disk_time[4]; /* inode disk times */
};

static inline void get_extent_info(struct extent_info *ext,
                                        struct f2fs_extent *i_ext)
{
        ext->fofs = le32_to_cpu(i_ext->fofs);
        ext->blk = le32_to_cpu(i_ext->blk);
        ext->len = le32_to_cpu(i_ext->len);
}

static inline void set_raw_extent(struct extent_info *ext,
                                        struct f2fs_extent *i_ext)
{
        i_ext->fofs = cpu_to_le32(ext->fofs);
        i_ext->blk = cpu_to_le32(ext->blk);
        i_ext->len = cpu_to_le32(ext->len);
}

static inline void set_extent_info(struct extent_info *ei, unsigned int fofs,
                                                u32 blk, unsigned int len)
{
        ei->fofs = fofs;
        ei->blk = blk;
        ei->len = len;
}

static inline bool __is_discard_mergeable(struct discard_info *back,
                                                struct discard_info *front)
{
        return back->lstart + back->len == front->lstart;
}

static inline bool __is_discard_back_mergeable(struct discard_info *cur,
                                                struct discard_info *back)
{
        return __is_discard_mergeable(back, cur);
}

static inline bool __is_discard_front_mergeable(struct discard_info *cur,
                                                struct discard_info *front)
{
        return __is_discard_mergeable(cur, front);
}

static inline bool __is_extent_mergeable(struct extent_info *back,
                                                struct extent_info *front)
{
        return (back->fofs + back->len == front->fofs &&
                        back->blk + back->len == front->blk);
}

static inline bool __is_back_mergeable(struct extent_info *cur,
                                                struct extent_info *back)
{
        return __is_extent_mergeable(back, cur);
}

static inline bool __is_front_mergeable(struct extent_info *cur,
                                                struct extent_info *front)
{
        return __is_extent_mergeable(cur, front);
}

extern void f2fs_mark_inode_dirty_sync(struct inode *inode, bool sync);
static inline void __try_update_largest_extent(struct inode *inode,
                        struct extent_tree *et, struct extent_node *en)
{
        if (en->ei.len > et->largest.len) {
                et->largest = en->ei;
                f2fs_mark_inode_dirty_sync(inode, true);
        }
}

/*
 * For free nid management
 */
enum nid_state {
        FREE_NID,               /* newly added to free nid list */
        PREALLOC_NID,           /* it is preallocated */
        MAX_NID_STATE,
};

struct f2fs_nm_info {
        block_t nat_blkaddr;            /* base disk address of NAT */
        nid_t max_nid;                  /* maximum possible node ids */
        nid_t available_nids;           /* # of available node ids */
        nid_t next_scan_nid;            /* the next nid to be scanned */
        unsigned int ram_thresh;        /* control the memory footprint */
        unsigned int ra_nid_pages;      /* # of nid pages to be readaheaded */
        unsigned int dirty_nats_ratio;  /* control dirty nats ratio threshold */

        /* NAT cache management */
        struct radix_tree_root nat_root;/* root of the nat entry cache */
        struct radix_tree_root nat_set_root;/* root of the nat set cache */
        struct rw_semaphore nat_tree_lock;      /* protect nat_tree_lock */
        struct list_head nat_entries;   /* cached nat entry list (clean) */
        unsigned int nat_cnt;           /* the # of cached nat entries */
        unsigned int dirty_nat_cnt;     /* total num of nat entries in set */
        unsigned int nat_blocks;        /* # of nat blocks */

        /* free node ids management */
        struct radix_tree_root free_nid_root;/* root of the free_nid cache */
        struct list_head free_nid_list;         /* list for free nids excluding preallocated nids */
        unsigned int nid_cnt[MAX_NID_STATE];    /* the number of free node id */
        spinlock_t nid_list_lock;       /* protect nid lists ops */
        struct mutex build_lock;        /* lock for build free nids */
        unsigned char **free_nid_bitmap;
        unsigned char *nat_block_bitmap;
        unsigned short *free_nid_count; /* free nid count of NAT block */

        /* for checkpoint */
        char *nat_bitmap;               /* NAT bitmap pointer */

        unsigned int nat_bits_blocks;   /* # of nat bits blocks */
        unsigned char *nat_bits;        /* NAT bits blocks */
        unsigned char *full_nat_bits;   /* full NAT pages */
        unsigned char *empty_nat_bits;  /* empty NAT pages */
#ifdef CONFIG_F2FS_CHECK_FS
        char *nat_bitmap_mir;           /* NAT bitmap mirror */
#endif
        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 */
        bool node_changed;              /* is node block changed */
        char cur_level;                 /* level of hole node page */
        char max_level;                 /* level of current page located */
        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)
{
        memset(dn, 0, sizeof(*dn));
        dn->inode = inode;
        dn->inode_page = ipage;
        dn->node_page = npage;
        dn->nid = nid;
}

/*
 * 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 flush_cmd {
        struct completion wait;
        struct llist_node llnode;
        nid_t ino;
        int ret;
};

struct flush_cmd_control {
        struct task_struct *f2fs_issue_flush;   /* flush thread */
        wait_queue_head_t flush_wait_queue;     /* waiting queue for wake-up */
        atomic_t issued_flush;                  /* # of issued flushes */
        atomic_t issing_flush;                  /* # of issing flushes */
        struct llist_head issue_list;           /* list for command issue */
        struct llist_node *dispatch_list;       /* list for command dispatch */
};

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 rw_semaphore curseg_lock;        /* for preventing curseg change */

        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 */

        /* a threshold to reclaim prefree segments */
        unsigned int rec_prefree_segments;

        /* for batched trimming */
        unsigned int trim_sections;             /* # of sections to trim */

        struct list_head sit_entry_set; /* sit entry set list */

        unsigned int ipu_policy;        /* in-place-update policy */
        unsigned int min_ipu_util;      /* in-place-update threshold */
        unsigned int min_fsync_blocks;  /* threshold for fsync */
        unsigned int min_hot_blocks;    /* threshold for hot block allocation */
        unsigned int min_ssr_sections;  /* threshold to trigger SSR allocation */

        /* for flush command control */
        struct flush_cmd_control *fcc_info;

        /* for discard command control */
        struct discard_cmd_control *dcc_info;
};

/*
 * 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.
 */
#define WB_DATA_TYPE(p) (__is_cp_guaranteed(p) ? F2FS_WB_CP_DATA : F2FS_WB_DATA)
enum count_type {
        F2FS_DIRTY_DENTS,
        F2FS_DIRTY_DATA,
        F2FS_DIRTY_QDATA,
        F2FS_DIRTY_NODES,
        F2FS_DIRTY_META,
        F2FS_INMEM_PAGES,
        F2FS_DIRTY_IMETA,
        F2FS_WB_CP_DATA,
        F2FS_WB_DATA,
        NR_COUNT_TYPE,
};

/*
 * The below are the page types of bios used in submit_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.
 */
#define PAGE_TYPE_OF_BIO(type)  ((type) > META ? META : (type))
enum page_type {
        DATA,
        NODE,
        META,
        NR_PAGE_TYPE,
        META_FLUSH,
        INMEM,          /* the below types are used by tracepoints only. */
        INMEM_DROP,
        INMEM_INVALIDATE,
        INMEM_REVOKE,
        IPU,
        OPU,
};

enum temp_type {
        HOT = 0,        /* must be zero for meta bio */
        WARM,
        COLD,
        NR_TEMP_TYPE,
};

enum need_lock_type {
        LOCK_REQ = 0,
        LOCK_DONE,
        LOCK_RETRY,
};

enum cp_reason_type {
        CP_NO_NEEDED,
        CP_NON_REGULAR,
        CP_HARDLINK,
        CP_SB_NEED_CP,
        CP_WRONG_PINO,
        CP_NO_SPC_ROLL,
        CP_NODE_NEED_CP,
        CP_FASTBOOT_MODE,
        CP_SPEC_LOG_NUM,
        CP_RECOVER_DIR,
};

enum iostat_type {
        APP_DIRECT_IO,                  /* app direct IOs */
        APP_BUFFERED_IO,                /* app buffered IOs */
        APP_WRITE_IO,                   /* app write IOs */
        APP_MAPPED_IO,                  /* app mapped IOs */
        FS_DATA_IO,                     /* data IOs from kworker/fsync/reclaimer */
        FS_NODE_IO,                     /* node IOs from kworker/fsync/reclaimer */
        FS_META_IO,                     /* meta IOs from kworker/reclaimer */
        FS_GC_DATA_IO,                  /* data IOs from forground gc */
        FS_GC_NODE_IO,                  /* node IOs from forground gc */
        FS_CP_DATA_IO,                  /* data IOs from checkpoint */
        FS_CP_NODE_IO,                  /* node IOs from checkpoint */
        FS_CP_META_IO,                  /* meta IOs from checkpoint */
        FS_DISCARD,                     /* discard */
        NR_IO_TYPE,
};

struct f2fs_io_info {
        struct f2fs_sb_info *sbi;       /* f2fs_sb_info pointer */
        nid_t ino;              /* inode number */
        enum page_type type;    /* contains DATA/NODE/META/META_FLUSH */
        enum temp_type temp;    /* contains HOT/WARM/COLD */
        int op;                 /* contains REQ_OP_ */
        int op_flags;           /* req_flag_bits */
        block_t new_blkaddr;    /* new block address to be written */
        block_t old_blkaddr;    /* old block address before Cow */

        struct page *page;      /* page to be written */
        struct page *encrypted_page;    /* encrypted page */
        struct list_head list;          /* serialize IOs */
        bool submitted;         /* indicate IO submission */
        int need_lock;          /* indicate we need to lock cp_rwsem */
        bool in_list;           /* indicate fio is in io_list */
        bool is_meta;           /* indicate borrow meta inode mapping or not */
        enum iostat_type io_type;       /* io type */
        struct writeback_control *io_wbc; /* writeback control */
};

#define is_read_io(rw) ((rw) == READ)
struct f2fs_bio_info {
        struct f2fs_sb_info *sbi;       /* f2fs superblock */
        struct bio *bio;                /* bios to merge */
        sector_t last_block_in_bio;     /* last block number */
        struct f2fs_io_info fio;        /* store buffered io info. */
        struct rw_semaphore io_rwsem;   /* blocking op for bio */
        spinlock_t io_lock;             /* serialize DATA/NODE IOs */
        struct list_head io_list;       /* track fios */
};

#define FDEV(i)                         (sbi->devs[i])
#define RDEV(i)                         (raw_super->devs[i])
struct f2fs_dev_info {
        struct block_device *bdev;
        char path[MAX_PATH_LEN];
        unsigned int total_segments;
        block_t start_blk;
        block_t end_blk;
#ifdef CONFIG_BLK_DEV_ZONED
        unsigned int nr_blkz;                   /* Total number of zones */
        u8 *blkz_type;                          /* Array of zones type */
#endif
};

enum inode_type {
        DIR_INODE,                      /* for dirty dir inode */
        FILE_INODE,                     /* for dirty regular/symlink inode */
        DIRTY_META,                     /* for all dirtied inode metadata */
        ATOMIC_FILE,                    /* for all atomic files */
        NR_INODE_TYPE,
};

/* for inner inode cache management */
struct inode_management {
        struct radix_tree_root ino_root;        /* ino entry array */
        spinlock_t ino_lock;                    /* for ino entry lock */
        struct list_head ino_list;              /* inode list head */
        unsigned long ino_num;                  /* number of entries */
};

/* For s_flag in struct f2fs_sb_info */
enum {
        SBI_IS_DIRTY,                           /* dirty flag for checkpoint */
        SBI_IS_CLOSE,                           /* specify unmounting */
        SBI_NEED_FSCK,                          /* need fsck.f2fs to fix */
        SBI_POR_DOING,                          /* recovery is doing or not */
        SBI_NEED_SB_WRITE,                      /* need to recover superblock */
        SBI_NEED_CP,                            /* need to checkpoint */
};

enum {
        CP_TIME,
        REQ_TIME,
        MAX_TIME,
};

enum {
        WHINT_MODE_OFF,         /* not pass down write hints */
        WHINT_MODE_USER,        /* try to pass down hints given by users */
        WHINT_MODE_FS,          /* pass down hints with F2FS policy */
};

enum {
        ALLOC_MODE_DEFAULT,     /* stay default */
        ALLOC_MODE_REUSE,       /* reuse segments as much as possible */
};

enum fsync_mode {
        FSYNC_MODE_POSIX,       /* fsync follows posix semantics */
        FSYNC_MODE_STRICT,      /* fsync behaves in line with ext4 */
};

#ifdef CONFIG_F2FS_FS_ENCRYPTION
#define DUMMY_ENCRYPTION_ENABLED(sbi) \
                        (unlikely(F2FS_OPTION(sbi).test_dummy_encryption))
#else
#define DUMMY_ENCRYPTION_ENABLED(sbi) (0)
#endif

struct f2fs_sb_info {
        struct super_block *sb;                 /* pointer to VFS super block */
        struct proc_dir_entry *s_proc;          /* proc entry */
        struct f2fs_super_block *raw_super;     /* raw super block pointer */
        struct rw_semaphore sb_lock;            /* lock for raw super block */
        int valid_super_block;                  /* valid super block no */
        unsigned long s_flag;                           /* flags for sbi */

#ifdef CONFIG_BLK_DEV_ZONED
        unsigned int blocks_per_blkz;           /* F2FS blocks per zone */
        unsigned int log_blocks_per_blkz;       /* log2 F2FS blocks per zone */
#endif

        /* 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 */

        /* for bio operations */
        struct f2fs_bio_info *write_io[NR_PAGE_TYPE];   /* for write bios */
        struct mutex wio_mutex[NR_PAGE_TYPE - 1][NR_TEMP_TYPE];
                                                /* bio ordering for NODE/DATA */
        mempool_t *write_io_dummy;              /* Dummy pages */

        /* for checkpoint */
        struct f2fs_checkpoint *ckpt;           /* raw checkpoint pointer */
        int cur_cp_pack;                        /* remain current cp pack */
        spinlock_t cp_lock;                     /* for flag in ckpt */
        struct inode *meta_inode;               /* cache meta blocks */
        struct mutex cp_mutex;                  /* checkpoint procedure lock */
        struct rw_semaphore cp_rwsem;           /* blocking FS operations */
        struct rw_semaphore node_write;         /* locking node writes */
        struct rw_semaphore node_change;        /* locking node change */
        wait_queue_head_t cp_wait;
        unsigned long last_time[MAX_TIME];      /* to store time in jiffies */
        long interval_time[MAX_TIME];           /* to store thresholds */

        struct inode_management im[MAX_INO_ENTRY];      /* manage inode cache */

        /* for orphan inode, use 0'th array */
        unsigned int max_orphans;               /* max orphan inodes */

        /* for inode management */
        struct list_head inode_list[NR_INODE_TYPE];     /* dirty inode list */
        spinlock_t inode_lock[NR_INODE_TYPE];   /* for dirty inode list lock */

        /* for extent tree cache */
        struct radix_tree_root extent_tree_root;/* cache extent cache entries */
        struct mutex extent_tree_lock;  /* locking extent radix tree */
        struct list_head extent_list;           /* lru list for shrinker */
        spinlock_t extent_lock;                 /* locking extent lru list */
        atomic_t total_ext_tree;                /* extent tree count */
        struct list_head zombie_list;           /* extent zombie tree list */
        atomic_t total_zombie_tree;             /* extent zombie tree count */
        atomic_t total_ext_node;                /* extent info count */

        /* basic filesystem 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 */
        loff_t max_file_blocks;                 /* max block index of file */
        int dir_level;                          /* directory level */
        unsigned int trigger_ssr_threshold;     /* threshold to trigger ssr */
        int readdir_ra;                         /* readahead inode in readdir */

        block_t user_block_count;               /* # of user blocks */
        block_t total_valid_block_count;        /* # of valid blocks */
        block_t discard_blks;                   /* discard command candidats */
        block_t last_valid_block_count;         /* for recovery */
        block_t reserved_blocks;                /* configurable reserved blocks */
        block_t current_reserved_blocks;        /* current reserved blocks */

        unsigned int nquota_files;              /* # of quota sysfile */

        u32 s_next_generation;                  /* for NFS support */

        /* # of pages, see count_type */
        atomic_t nr_pages[NR_COUNT_TYPE];
        /* # of allocated blocks */
        struct percpu_counter alloc_valid_block_count;

        /* writeback control */
        atomic_t wb_sync_req;                   /* count # of WB_SYNC threads */

        /* valid inode count */
        struct percpu_counter total_valid_inode_count;

        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 */
        unsigned int cur_victim_sec;            /* current victim section num */

        /* threshold for converting bg victims for fg */
        u64 fggc_threshold;

        /* threshold for gc trials on pinned files */
        u64 gc_pin_file_threshold;

        /* maximum # of trials to find a victim segment for SSR and GC */
        unsigned int max_victim_search;

        /*
         * for stat information.
         * one is for the LFS mode, and the other is for the SSR mode.
         */
#ifdef CONFIG_F2FS_STAT_FS
        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 */
        atomic_t inplace_count;         /* # of inplace update */
        atomic64_t total_hit_ext;               /* # of lookup extent cache */
        atomic64_t read_hit_rbtree;             /* # of hit rbtree extent node */
        atomic64_t read_hit_largest;            /* # of hit largest extent node */
        atomic64_t read_hit_cached;             /* # of hit cached extent node */
        atomic_t inline_xattr;                  /* # of inline_xattr inodes */
        atomic_t inline_inode;                  /* # of inline_data inodes */
        atomic_t inline_dir;                    /* # of inline_dentry inodes */
        atomic_t aw_cnt;                        /* # of atomic writes */
        atomic_t vw_cnt;                        /* # of volatile writes */
        atomic_t max_aw_cnt;                    /* max # of atomic writes */
        atomic_t max_vw_cnt;                    /* max # of volatile writes */
        int bg_gc;                              /* background gc calls */
        unsigned int ndirty_inode[NR_INODE_TYPE];       /* # of dirty inodes */
#endif
        spinlock_t stat_lock;                   /* lock for stat operations */

        /* For app/fs IO statistics */
        spinlock_t iostat_lock;
        unsigned long long write_iostat[NR_IO_TYPE];
        bool iostat_enable;

        /* For sysfs suppport */
        struct kobject s_kobj;
        struct completion s_kobj_unregister;

        /* For shrinker support */
        struct list_head s_list;
        int s_ndevs;                            /* number of devices */
        struct f2fs_dev_info *devs;             /* for device list */
        unsigned int dirty_device;              /* for checkpoint data flush */
        spinlock_t dev_lock;                    /* protect dirty_device */
        struct mutex umount_mutex;
        unsigned int shrinker_run_no;

        /* For write statistics */
        u64 sectors_written_start;
        u64 kbytes_written;

        /* Reference to checksum algorithm driver via cryptoapi */
        struct crypto_shash *s_chksum_driver;

        /* Precomputed FS UUID checksum for seeding other checksums */
        __u32 s_chksum_seed;
};

#ifdef CONFIG_F2FS_FAULT_INJECTION
#define f2fs_show_injection_info(type)                          \
        printk("%sF2FS-fs : inject %s in %s of %pF\n",          \
                KERN_INFO, fault_name[type],                    \
                __func__, __builtin_return_address(0))
static inline bool time_to_inject(struct f2fs_sb_info *sbi, int type)
{
        struct f2fs_fault_info *ffi = &F2FS_OPTION(sbi).fault_info;

        if (!ffi->inject_rate)
                return false;

        if (!IS_FAULT_SET(ffi, type))
                return false;

        atomic_inc(&ffi->inject_ops);
        if (atomic_read(&ffi->inject_ops) >= ffi->inject_rate) {
                atomic_set(&ffi->inject_ops, 0);
                return true;
        }
        return false;
}
#endif

/* For write statistics. Suppose sector size is 512 bytes,
 * and the return value is in kbytes. s is of struct f2fs_sb_info.
 */
#define BD_PART_WRITTEN(s)                                               \
(((u64)part_stat_read((s)->sb->s_bdev->bd_part, sectors[1]) -            \
                (s)->sectors_written_start) >> 1)

static inline void f2fs_update_time(struct f2fs_sb_info *sbi, int type)
{
        sbi->last_time[type] = jiffies;
}

static inline bool f2fs_time_over(struct f2fs_sb_info *sbi, int type)
{
        unsigned long interval = sbi->interval_time[type] * HZ;

        return time_after(jiffies, sbi->last_time[type] + interval);
}

static inline bool is_idle(struct f2fs_sb_info *sbi)
{
        struct block_device *bdev = sbi->sb->s_bdev;
        struct request_queue *q = bdev_get_queue(bdev);
        struct request_list *rl = &q->root_rl;

        if (rl->count[BLK_RW_SYNC] || rl->count[BLK_RW_ASYNC])
                return 0;

        return f2fs_time_over(sbi, REQ_TIME);
}

/*
 * Inline functions
 */
static inline u32 __f2fs_crc32(struct f2fs_sb_info *sbi, u32 crc,
                              const void *address, unsigned int length)
{
        struct {
                struct shash_desc shash;
                char ctx[4];
        } desc;
        int err;

        BUG_ON(crypto_shash_descsize(sbi->s_chksum_driver) != sizeof(desc.ctx));

        desc.shash.tfm = sbi->s_chksum_driver;
        desc.shash.flags = 0;
        *(u32 *)desc.ctx = crc;

        err = crypto_shash_update(&desc.shash, address, length);
        BUG_ON(err);

        return *(u32 *)desc.ctx;
}

static inline u32 f2fs_crc32(struct f2fs_sb_info *sbi, const void *address,
                           unsigned int length)
{
        return __f2fs_crc32(sbi, F2FS_SUPER_MAGIC, address, length);
}

static inline bool f2fs_crc_valid(struct f2fs_sb_info *sbi, __u32 blk_crc,
                                  void *buf, size_t buf_size)
{
        return f2fs_crc32(sbi, buf, buf_size) == blk_crc;
}

static inline u32 f2fs_chksum(struct f2fs_sb_info *sbi, u32 crc,
                              const void *address, unsigned int length)
{
        return __f2fs_crc32(sbi, crc, address, length);
}

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_sb_info *F2FS_I_SB(struct inode *inode)
{
        return F2FS_SB(inode->i_sb);
}

static inline struct f2fs_sb_info *F2FS_M_SB(struct address_space *mapping)
{
        return F2FS_I_SB(mapping->host);
}

static inline struct f2fs_sb_info *F2FS_P_SB(struct page *page)
{
        return F2FS_M_SB(page->mapping);
}

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_node *F2FS_NODE(struct page *page)
{
        return (struct f2fs_node *)page_address(page);
}

static inline struct f2fs_inode *F2FS_INODE(struct page *page)
{
        return &((struct f2fs_node *)page_address(page))->i;
}

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 struct address_space *META_MAPPING(struct f2fs_sb_info *sbi)
{
        return sbi->meta_inode->i_mapping;
}

static inline struct address_space *NODE_MAPPING(struct f2fs_sb_info *sbi)
{
        return sbi->node_inode->i_mapping;
}

static inline bool is_sbi_flag_set(struct f2fs_sb_info *sbi, unsigned int type)
{
        return test_bit(type, &sbi->s_flag);
}

static inline void set_sbi_flag(struct f2fs_sb_info *sbi, unsigned int type)
{
        set_bit(type, &sbi->s_flag);
}

static inline void clear_sbi_flag(struct f2fs_sb_info *sbi, unsigned int type)
{
        clear_bit(type, &sbi->s_flag);
}

static inline unsigned long long cur_cp_version(struct f2fs_checkpoint *cp)
{
        return le64_to_cpu(cp->checkpoint_ver);
}

static inline unsigned long f2fs_qf_ino(struct super_block *sb, int type)
{
        if (type < F2FS_MAX_QUOTAS)
                return le32_to_cpu(F2FS_SB(sb)->raw_super->qf_ino[type]);
        return 0;
}

static inline __u64 cur_cp_crc(struct f2fs_checkpoint *cp)
{
        size_t crc_offset = le32_to_cpu(cp->checksum_offset);
        return le32_to_cpu(*((__le32 *)((unsigned char *)cp + crc_offset)));
}

static inline bool __is_set_ckpt_flags(struct f2fs_checkpoint *cp, unsigned int f)
{
        unsigned int ckpt_flags = le32_to_cpu(cp->ckpt_flags);

        return ckpt_flags & f;
}

static inline bool is_set_ckpt_flags(struct f2fs_sb_info *sbi, unsigned int f)
{
        return __is_set_ckpt_flags(F2FS_CKPT(sbi), f);
}

static inline void __set_ckpt_flags(struct f2fs_checkpoint *cp, unsigned int f)
{
        unsigned int ckpt_flags;

        ckpt_flags = le32_to_cpu(cp->ckpt_flags);
        ckpt_flags |= f;
        cp->ckpt_flags = cpu_to_le32(ckpt_flags);
}

static inline void set_ckpt_flags(struct f2fs_sb_info *sbi, unsigned int f)
{
        unsigned long flags;

        spin_lock_irqsave(&sbi->cp_lock, flags);
        __set_ckpt_flags(F2FS_CKPT(sbi), f);
        spin_unlock_irqrestore(&sbi->cp_lock, flags);
}

static inline void __clear_ckpt_flags(struct f2fs_checkpoint *cp, unsigned int f)
{
        unsigned int ckpt_flags;

        ckpt_flags = le32_to_cpu(cp->ckpt_flags);
        ckpt_flags &= (~f);
        cp->ckpt_flags = cpu_to_le32(ckpt_flags);
}

static inline void clear_ckpt_flags(struct f2fs_sb_info *sbi, unsigned int f)
{
        unsigned long flags;

        spin_lock_irqsave(&sbi->cp_lock, flags);
        __clear_ckpt_flags(F2FS_CKPT(sbi), f);
        spin_unlock_irqrestore(&sbi->cp_lock, flags);
}

static inline void disable_nat_bits(struct f2fs_sb_info *sbi, bool lock)
{
        unsigned long flags;

        set_sbi_flag(sbi, SBI_NEED_FSCK);

        if (lock)
                spin_lock_irqsave(&sbi->cp_lock, flags);
        __clear_ckpt_flags(F2FS_CKPT(sbi), CP_NAT_BITS_FLAG);
        kfree(NM_I(sbi)->nat_bits);
        NM_I(sbi)->nat_bits = NULL;
        if (lock)
                spin_unlock_irqrestore(&sbi->cp_lock, flags);
}

static inline bool enabled_nat_bits(struct f2fs_sb_info *sbi,
                                        struct cp_control *cpc)
{
        bool set = is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG);

        return (cpc) ? (cpc->reason & CP_UMOUNT) && set : set;
}

static inline void f2fs_lock_op(struct f2fs_sb_info *sbi)
{
        down_read(&sbi->cp_rwsem);
}

static inline int f2fs_trylock_op(struct f2fs_sb_info *sbi)
{
        return down_read_trylock(&sbi->cp_rwsem);
}

static inline void f2fs_unlock_op(struct f2fs_sb_info *sbi)
{
        up_read(&sbi->cp_rwsem);
}

static inline void f2fs_lock_all(struct f2fs_sb_info *sbi)
{
        down_write(&sbi->cp_rwsem);
}

static inline void f2fs_unlock_all(struct f2fs_sb_info *sbi)
{
        up_write(&sbi->cp_rwsem);
}

static inline int __get_cp_reason(struct f2fs_sb_info *sbi)
{
        int reason = CP_SYNC;

        if (test_opt(sbi, FASTBOOT))
                reason = CP_FASTBOOT;
        if (is_sbi_flag_set(sbi, SBI_IS_CLOSE))
                reason = CP_UMOUNT;
        return reason;
}

static inline bool __remain_node_summaries(int reason)
{
        return (reason & (CP_UMOUNT | CP_FASTBOOT));
}

static inline bool __exist_node_summaries(struct f2fs_sb_info *sbi)
{
        return (is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG) ||
                        is_set_ckpt_flags(sbi, CP_FASTBOOT_FLAG));
}

/*
 * Check whether the given nid is within node id range.
 */
static inline int check_nid_range(struct f2fs_sb_info *sbi, nid_t nid)
{
        if (unlikely(nid < F2FS_ROOT_INO(sbi)))
                return -EINVAL;
        if (unlikely(nid >= NM_I(sbi)->max_nid))
                return -EINVAL;
        return 0;
}

/*
 * Check whether the inode has blocks or not
 */
static inline int F2FS_HAS_BLOCKS(struct inode *inode)
{
        block_t xattr_block = F2FS_I(inode)->i_xattr_nid ? 1 : 0;

        return (inode->i_blocks >> F2FS_LOG_SECTORS_PER_BLOCK) > xattr_block;
}

static inline bool f2fs_has_xattr_block(unsigned int ofs)
{
        return ofs == XATTR_NODE_OFFSET;
}

static inline bool __allow_reserved_blocks(struct f2fs_sb_info *sbi,
                                        struct inode *inode)
{
        if (!inode)
                return true;
        if (!test_opt(sbi, RESERVE_ROOT))
                return false;
        if (IS_NOQUOTA(inode))
                return true;
        if (uid_eq(F2FS_OPTION(sbi).s_resuid, current_fsuid()))
                return true;
        if (!gid_eq(F2FS_OPTION(sbi).s_resgid, GLOBAL_ROOT_GID) &&
                                        in_group_p(F2FS_OPTION(sbi).s_resgid))
                return true;
        if (capable(CAP_SYS_RESOURCE))
                return true;
        return false;
}

static inline void f2fs_i_blocks_write(struct inode *, block_t, bool, bool);
static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,
                                 struct inode *inode, blkcnt_t *count)
{
        blkcnt_t diff = 0, release = 0;
        block_t avail_user_block_count;
        int ret;

        ret = dquot_reserve_block(inode, *count);
        if (ret)
                return ret;

#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(sbi, FAULT_BLOCK)) {
                f2fs_show_injection_info(FAULT_BLOCK);
                release = *count;
                goto enospc;
        }
#endif
        /*
         * let's increase this in prior to actual block count change in order
         * for f2fs_sync_file to avoid data races when deciding checkpoint.
         */
        percpu_counter_add(&sbi->alloc_valid_block_count, (*count));

        spin_lock(&sbi->stat_lock);
        sbi->total_valid_block_count += (block_t)(*count);
        avail_user_block_count = sbi->user_block_count -
                                        sbi->current_reserved_blocks;

        if (!__allow_reserved_blocks(sbi, inode))
                avail_user_block_count -= F2FS_OPTION(sbi).root_reserved_blocks;

        if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
                diff = sbi->total_valid_block_count - avail_user_block_count;
                if (diff > *count)
                        diff = *count;
                *count -= diff;
                release = diff;
                sbi->total_valid_block_count -= diff;
                if (!*count) {
                        spin_unlock(&sbi->stat_lock);
                        percpu_counter_sub(&sbi->alloc_valid_block_count, diff);
                        goto enospc;
                }
        }
        spin_unlock(&sbi->stat_lock);

        if (unlikely(release))
                dquot_release_reservation_block(inode, release);
        f2fs_i_blocks_write(inode, *count, true, true);
        return 0;

enospc:
        dquot_release_reservation_block(inode, release);
        return -ENOSPC;
}

static inline void dec_valid_block_count(struct f2fs_sb_info *sbi,
                                                struct inode *inode,
                                                block_t count)
{
        blkcnt_t sectors = count << F2FS_LOG_SECTORS_PER_BLOCK;

        spin_lock(&sbi->stat_lock);
        f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
        f2fs_bug_on(sbi, inode->i_blocks < sectors);
        sbi->total_valid_block_count -= (block_t)count;
        if (sbi->reserved_blocks &&
                sbi->current_reserved_blocks < sbi->reserved_blocks)
                sbi->current_reserved_blocks = min(sbi->reserved_blocks,
                                        sbi->current_reserved_blocks + count);
        spin_unlock(&sbi->stat_lock);
        f2fs_i_blocks_write(inode, count, false, true);
}

static inline void inc_page_count(struct f2fs_sb_info *sbi, int count_type)
{
        atomic_inc(&sbi->nr_pages[count_type]);

        if (count_type == F2FS_DIRTY_DATA || count_type == F2FS_INMEM_PAGES ||
                count_type == F2FS_WB_CP_DATA || count_type == F2FS_WB_DATA)
                return;

        set_sbi_flag(sbi, SBI_IS_DIRTY);
}

static inline void inode_inc_dirty_pages(struct inode *inode)
{
        atomic_inc(&F2FS_I(inode)->dirty_pages);
        inc_page_count(F2FS_I_SB(inode), S_ISDIR(inode->i_mode) ?
                                F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA);
        if (IS_NOQUOTA(inode))
                inc_page_count(F2FS_I_SB(inode), F2FS_DIRTY_QDATA);
}

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_pages(struct inode *inode)
{
        if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode) &&
                        !S_ISLNK(inode->i_mode))
                return;

        atomic_dec(&F2FS_I(inode)->dirty_pages);
        dec_page_count(F2FS_I_SB(inode), S_ISDIR(inode->i_mode) ?
                                F2FS_DIRTY_DENTS : F2FS_DIRTY_DATA);
        if (IS_NOQUOTA(inode))
                dec_page_count(F2FS_I_SB(inode), F2FS_DIRTY_QDATA);
}

static inline s64 get_pages(struct f2fs_sb_info *sbi, int count_type)
{
        return atomic_read(&sbi->nr_pages[count_type]);
}

static inline int get_dirty_pages(struct inode *inode)
{
        return atomic_read(&F2FS_I(inode)->dirty_pages);
}

static inline int get_blocktype_secs(struct f2fs_sb_info *sbi, int block_type)
{
        unsigned int pages_per_sec = sbi->segs_per_sec * sbi->blocks_per_seg;
        unsigned int segs = (get_pages(sbi, block_type) + pages_per_sec - 1) >>
                                                sbi->log_blocks_per_seg;

        return segs / sbi->segs_per_sec;
}

static inline block_t valid_user_blocks(struct f2fs_sb_info *sbi)
{
        return sbi->total_valid_block_count;
}

static inline block_t discard_blocks(struct f2fs_sb_info *sbi)
{
        return sbi->discard_blks;
}

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 block_t __cp_payload(struct f2fs_sb_info *sbi)
{
        return le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_payload);
}

static inline void *__bitmap_ptr(struct f2fs_sb_info *sbi, int flag)
{
        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
        int offset;

        if (is_set_ckpt_flags(sbi, CP_LARGE_NAT_BITMAP_FLAG)) {
                offset = (flag == SIT_BITMAP) ?
                        le32_to_cpu(ckpt->nat_ver_bitmap_bytesize) : 0;
                return &ckpt->sit_nat_version_bitmap + offset;
        }

        if (__cp_payload(sbi) > 0) {
                if (flag == NAT_BITMAP)
                        return &ckpt->sit_nat_version_bitmap;
                else
                        return (unsigned char *)ckpt + F2FS_BLKSIZE;
        } else {
                offset = (flag == NAT_BITMAP) ?
                        le32_to_cpu(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 = le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_blkaddr);

        if (sbi->cur_cp_pack == 2)
                start_addr += sbi->blocks_per_seg;
        return start_addr;
}

static inline block_t __start_cp_next_addr(struct f2fs_sb_info *sbi)
{
        block_t start_addr = le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_blkaddr);

        if (sbi->cur_cp_pack == 1)
                start_addr += sbi->blocks_per_seg;
        return start_addr;
}

static inline void __set_cp_next_pack(struct f2fs_sb_info *sbi)
{
        sbi->cur_cp_pack = (sbi->cur_cp_pack == 1) ? 2 : 1;
}

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 int inc_valid_node_count(struct f2fs_sb_info *sbi,
                                        struct inode *inode, bool is_inode)
{
        block_t valid_block_count;
        unsigned int valid_node_count;
        bool quota = inode && !is_inode;

        if (quota) {
                int ret = dquot_reserve_block(inode, 1);
                if (ret)
                        return ret;
        }

#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(sbi, FAULT_BLOCK)) {
                f2fs_show_injection_info(FAULT_BLOCK);
                goto enospc;
        }
#endif

        spin_lock(&sbi->stat_lock);

        valid_block_count = sbi->total_valid_block_count +
                                        sbi->current_reserved_blocks + 1;

        if (!__allow_reserved_blocks(sbi, inode))
                valid_block_count += F2FS_OPTION(sbi).root_reserved_blocks;

        if (unlikely(valid_block_count > sbi->user_block_count)) {
                spin_unlock(&sbi->stat_lock);
                goto enospc;
        }

        valid_node_count = sbi->total_valid_node_count + 1;
        if (unlikely(valid_node_count > sbi->total_node_count)) {
                spin_unlock(&sbi->stat_lock);
                goto enospc;
        }

        sbi->total_valid_node_count++;
        sbi->total_valid_block_count++;
        spin_unlock(&sbi->stat_lock);

        if (inode) {
                if (is_inode)
                        f2fs_mark_inode_dirty_sync(inode, true);
                else
                        f2fs_i_blocks_write(inode, 1, true, true);
        }

        percpu_counter_inc(&sbi->alloc_valid_block_count);
        return 0;

enospc:
        if (quota)
                dquot_release_reservation_block(inode, 1);
        return -ENOSPC;
}

static inline void dec_valid_node_count(struct f2fs_sb_info *sbi,
                                        struct inode *inode, bool is_inode)
{
        spin_lock(&sbi->stat_lock);

        f2fs_bug_on(sbi, !sbi->total_valid_block_count);
        f2fs_bug_on(sbi, !sbi->total_valid_node_count);
        f2fs_bug_on(sbi, !is_inode && !inode->i_blocks);

        sbi->total_valid_node_count--;
        sbi->total_valid_block_count--;
        if (sbi->reserved_blocks &&
                sbi->current_reserved_blocks < sbi->reserved_blocks)
                sbi->current_reserved_blocks++;

        spin_unlock(&sbi->stat_lock);

        if (!is_inode)
                f2fs_i_blocks_write(inode, 1, false, true);
}

static inline unsigned int valid_node_count(struct f2fs_sb_info *sbi)
{
        return sbi->total_valid_node_count;
}

static inline void inc_valid_inode_count(struct f2fs_sb_info *sbi)
{
        percpu_counter_inc(&sbi->total_valid_inode_count);
}

static inline void dec_valid_inode_count(struct f2fs_sb_info *sbi)
{
        percpu_counter_dec(&sbi->total_valid_inode_count);
}

static inline s64 valid_inode_count(struct f2fs_sb_info *sbi)
{
        return percpu_counter_sum_positive(&sbi->total_valid_inode_count);
}

static inline struct page *f2fs_grab_cache_page(struct address_space *mapping,
                                                pgoff_t index, bool for_write)
{
#ifdef CONFIG_F2FS_FAULT_INJECTION
        struct page *page = find_lock_page(mapping, index);

        if (page)
                return page;

        if (time_to_inject(F2FS_M_SB(mapping), FAULT_PAGE_ALLOC)) {
                f2fs_show_injection_info(FAULT_PAGE_ALLOC);
                return NULL;
        }
#endif
        if (!for_write)
                return grab_cache_page(mapping, index);
        return grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
}

static inline struct page *f2fs_pagecache_get_page(
                                struct address_space *mapping, pgoff_t index,
                                int fgp_flags, gfp_t gfp_mask)
{
#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(F2FS_M_SB(mapping), FAULT_PAGE_GET)) {
                f2fs_show_injection_info(FAULT_PAGE_GET);
                return NULL;
        }
#endif
        return pagecache_get_page(mapping, index, fgp_flags, gfp_mask);
}

static inline void f2fs_copy_page(struct page *src, struct page *dst)
{
        char *src_kaddr = kmap(src);
        char *dst_kaddr = kmap(dst);

        memcpy(dst_kaddr, src_kaddr, PAGE_SIZE);
        kunmap(dst);
        kunmap(src);
}

static inline void f2fs_put_page(struct page *page, int unlock)
{
        if (!page)
                return;

        if (unlock) {
                f2fs_bug_on(F2FS_P_SB(page), !PageLocked(page));
                unlock_page(page);
        }
        put_page(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)
{
        return kmem_cache_create(name, size, 0, SLAB_RECLAIM_ACCOUNT, NULL);
}

static inline void *f2fs_kmem_cache_alloc(struct kmem_cache *cachep,
                                                gfp_t flags)
{
        void *entry;

        entry = kmem_cache_alloc(cachep, flags);
        if (!entry)
                entry = kmem_cache_alloc(cachep, flags | __GFP_NOFAIL);
        return entry;
}

static inline struct bio *f2fs_bio_alloc(struct f2fs_sb_info *sbi,
                                                int npages, bool no_fail)
{
        struct bio *bio;

        if (no_fail) {
                /* No failure on bio allocation */
                bio = bio_alloc(GFP_NOIO, npages);
                if (!bio)
                        bio = bio_alloc(GFP_NOIO | __GFP_NOFAIL, npages);
                return bio;
        }
#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(sbi, FAULT_ALLOC_BIO)) {
                f2fs_show_injection_info(FAULT_ALLOC_BIO);
                return NULL;
        }
#endif
        return bio_alloc(GFP_KERNEL, npages);
}

static inline void f2fs_radix_tree_insert(struct radix_tree_root *root,
                                unsigned long index, void *item)
{
        while (radix_tree_insert(root, index, item))
                cond_resched();
}

#define RAW_IS_INODE(p) ((p)->footer.nid == (p)->footer.ino)

static inline bool IS_INODE(struct page *page)
{
        struct f2fs_node *p = F2FS_NODE(page);

        return RAW_IS_INODE(p);
}

static inline int offset_in_addr(struct f2fs_inode *i)
{
        return (i->i_inline & F2FS_EXTRA_ATTR) ?
                        (le16_to_cpu(i->i_extra_isize) / sizeof(__le32)) : 0;
}

static inline __le32 *blkaddr_in_node(struct f2fs_node *node)
{
        return RAW_IS_INODE(node) ? node->i.i_addr : node->dn.addr;
}

static inline int f2fs_has_extra_attr(struct inode *inode);
static inline block_t datablock_addr(struct inode *inode,
                        struct page *node_page, unsigned int offset)
{
        struct f2fs_node *raw_node;
        __le32 *addr_array;
        int base = 0;
        bool is_inode = IS_INODE(node_page);

        raw_node = F2FS_NODE(node_page);

        /* from GC path only */
        if (is_inode) {
                if (!inode)
                        base = offset_in_addr(&raw_node->i);
                else if (f2fs_has_extra_attr(inode))
                        base = get_extra_isize(inode);
        }

        addr_array = blkaddr_in_node(raw_node);
        return le32_to_cpu(addr_array[base + 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 void f2fs_set_bit(unsigned int nr, char *addr)
{
        int mask;

        addr += (nr >> 3);
        mask = 1 << (7 - (nr & 0x07));
        *addr |= mask;
}

static inline void f2fs_clear_bit(unsigned int nr, char *addr)
{
        int mask;

        addr += (nr >> 3);
        mask = 1 << (7 - (nr & 0x07));
        *addr &= ~mask;
}

static inline int f2fs_test_and_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_test_and_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;
}

static inline void f2fs_change_bit(unsigned int nr, char *addr)
{
        int mask;

        addr += (nr >> 3);
        mask = 1 << (7 - (nr & 0x07));
        *addr ^= mask;
}

#define F2FS_REG_FLMASK         (~(FS_DIRSYNC_FL | FS_TOPDIR_FL))
#define F2FS_OTHER_FLMASK       (FS_NODUMP_FL | FS_NOATIME_FL)
#define F2FS_FL_INHERITED       (FS_PROJINHERIT_FL)

static inline __u32 f2fs_mask_flags(umode_t mode, __u32 flags)
{
        if (S_ISDIR(mode))
                return flags;
        else if (S_ISREG(mode))
                return flags & F2FS_REG_FLMASK;
        else
                return flags & F2FS_OTHER_FLMASK;
}

/* used for f2fs_inode_info->flags */
enum {
        FI_NEW_INODE,           /* indicate newly allocated inode */
        FI_DIRTY_INODE,         /* indicate inode is dirty or not */
        FI_AUTO_RECOVER,        /* indicate inode is recoverable */
        FI_DIRTY_DIR,           /* indicate directory has dirty pages */
        FI_INC_LINK,            /* need to increment i_nlink */
        FI_ACL_MODE,            /* indicate acl mode */
        FI_NO_ALLOC,            /* should not allocate any blocks */
        FI_FREE_NID,            /* free allocated nide */
        FI_NO_EXTENT,           /* not to use the extent cache */
        FI_INLINE_XATTR,        /* used for inline xattr */
        FI_INLINE_DATA,         /* used for inline data*/
        FI_INLINE_DENTRY,       /* used for inline dentry */
        FI_APPEND_WRITE,        /* inode has appended data */
        FI_UPDATE_WRITE,        /* inode has in-place-update data */
        FI_NEED_IPU,            /* used for ipu per file */
        FI_ATOMIC_FILE,         /* indicate atomic file */
        FI_ATOMIC_COMMIT,       /* indicate the state of atomical committing */
        FI_VOLATILE_FILE,       /* indicate volatile file */
        FI_FIRST_BLOCK_WRITTEN, /* indicate #0 data block was written */
        FI_DROP_CACHE,          /* drop dirty page cache */
        FI_DATA_EXIST,          /* indicate data exists */
        FI_INLINE_DOTS,         /* indicate inline dot dentries */
        FI_DO_DEFRAG,           /* indicate defragment is running */
        FI_DIRTY_FILE,          /* indicate regular/symlink has dirty pages */
        FI_NO_PREALLOC,         /* indicate skipped preallocated blocks */
        FI_HOT_DATA,            /* indicate file is hot */
        FI_EXTRA_ATTR,          /* indicate file has extra attribute */
        FI_PROJ_INHERIT,        /* indicate file inherits projectid */
        FI_PIN_FILE,            /* indicate file should not be gced */
};

static inline void __mark_inode_dirty_flag(struct inode *inode,
                                                int flag, bool set)
{
        switch (flag) {
        case FI_INLINE_XATTR:
        case FI_INLINE_DATA:
        case FI_INLINE_DENTRY:
        case FI_NEW_INODE:
                if (set)
                        return;
        case FI_DATA_EXIST:
        case FI_INLINE_DOTS:
        case FI_PIN_FILE:
                f2fs_mark_inode_dirty_sync(inode, true);
        }
}

static inline void set_inode_flag(struct inode *inode, int flag)
{
        if (!test_bit(flag, &F2FS_I(inode)->flags))
                set_bit(flag, &F2FS_I(inode)->flags);
        __mark_inode_dirty_flag(inode, flag, true);
}

static inline int is_inode_flag_set(struct inode *inode, int flag)
{
        return test_bit(flag, &F2FS_I(inode)->flags);
}

static inline void clear_inode_flag(struct inode *inode, int flag)
{
        if (test_bit(flag, &F2FS_I(inode)->flags))
                clear_bit(flag, &F2FS_I(inode)->flags);
        __mark_inode_dirty_flag(inode, flag, false);
}

static inline void set_acl_inode(struct inode *inode, umode_t mode)
{
        F2FS_I(inode)->i_acl_mode = mode;
        set_inode_flag(inode, FI_ACL_MODE);
        f2fs_mark_inode_dirty_sync(inode, false);
}

static inline void f2fs_i_links_write(struct inode *inode, bool inc)
{
        if (inc)
                inc_nlink(inode);
        else
                drop_nlink(inode);
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline void f2fs_i_blocks_write(struct inode *inode,
                                        block_t diff, bool add, bool claim)
{
        bool clean = !is_inode_flag_set(inode, FI_DIRTY_INODE);
        bool recover = is_inode_flag_set(inode, FI_AUTO_RECOVER);

        /* add = 1, claim = 1 should be dquot_reserve_block in pair */
        if (add) {
                if (claim)
                        dquot_claim_block(inode, diff);
                else
                        dquot_alloc_block_nofail(inode, diff);
        } else {
                dquot_free_block(inode, diff);
        }

        f2fs_mark_inode_dirty_sync(inode, true);
        if (clean || recover)
                set_inode_flag(inode, FI_AUTO_RECOVER);
}

static inline void f2fs_i_size_write(struct inode *inode, loff_t i_size)
{
        bool clean = !is_inode_flag_set(inode, FI_DIRTY_INODE);
        bool recover = is_inode_flag_set(inode, FI_AUTO_RECOVER);

        if (i_size_read(inode) == i_size)
                return;

        i_size_write(inode, i_size);
        f2fs_mark_inode_dirty_sync(inode, true);
        if (clean || recover)
                set_inode_flag(inode, FI_AUTO_RECOVER);
}

static inline void f2fs_i_depth_write(struct inode *inode, unsigned int depth)
{
        F2FS_I(inode)->i_current_depth = depth;
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline void f2fs_i_gc_failures_write(struct inode *inode,
                                        unsigned int count)
{
        F2FS_I(inode)->i_gc_failures = count;
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline void f2fs_i_xnid_write(struct inode *inode, nid_t xnid)
{
        F2FS_I(inode)->i_xattr_nid = xnid;
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline void f2fs_i_pino_write(struct inode *inode, nid_t pino)
{
        F2FS_I(inode)->i_pino = pino;
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline void get_inline_info(struct inode *inode, struct f2fs_inode *ri)
{
        struct f2fs_inode_info *fi = F2FS_I(inode);

        if (ri->i_inline & F2FS_INLINE_XATTR)
                set_bit(FI_INLINE_XATTR, &fi->flags);
        if (ri->i_inline & F2FS_INLINE_DATA)
                set_bit(FI_INLINE_DATA, &fi->flags);
        if (ri->i_inline & F2FS_INLINE_DENTRY)
                set_bit(FI_INLINE_DENTRY, &fi->flags);
        if (ri->i_inline & F2FS_DATA_EXIST)
                set_bit(FI_DATA_EXIST, &fi->flags);
        if (ri->i_inline & F2FS_INLINE_DOTS)
                set_bit(FI_INLINE_DOTS, &fi->flags);
        if (ri->i_inline & F2FS_EXTRA_ATTR)
                set_bit(FI_EXTRA_ATTR, &fi->flags);
        if (ri->i_inline & F2FS_PIN_FILE)
                set_bit(FI_PIN_FILE, &fi->flags);
}

static inline void set_raw_inline(struct inode *inode, struct f2fs_inode *ri)
{
        ri->i_inline = 0;

        if (is_inode_flag_set(inode, FI_INLINE_XATTR))
                ri->i_inline |= F2FS_INLINE_XATTR;
        if (is_inode_flag_set(inode, FI_INLINE_DATA))
                ri->i_inline |= F2FS_INLINE_DATA;
        if (is_inode_flag_set(inode, FI_INLINE_DENTRY))
                ri->i_inline |= F2FS_INLINE_DENTRY;
        if (is_inode_flag_set(inode, FI_DATA_EXIST))
                ri->i_inline |= F2FS_DATA_EXIST;
        if (is_inode_flag_set(inode, FI_INLINE_DOTS))
                ri->i_inline |= F2FS_INLINE_DOTS;
        if (is_inode_flag_set(inode, FI_EXTRA_ATTR))
                ri->i_inline |= F2FS_EXTRA_ATTR;
        if (is_inode_flag_set(inode, FI_PIN_FILE))
                ri->i_inline |= F2FS_PIN_FILE;
}

static inline int f2fs_has_extra_attr(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_EXTRA_ATTR);
}

static inline int f2fs_has_inline_xattr(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_INLINE_XATTR);
}

static inline unsigned int addrs_per_inode(struct inode *inode)
{
        return CUR_ADDRS_PER_INODE(inode) - get_inline_xattr_addrs(inode);
}

static inline void *inline_xattr_addr(struct inode *inode, struct page *page)
{
        struct f2fs_inode *ri = F2FS_INODE(page);

        return (void *)&(ri->i_addr[DEF_ADDRS_PER_INODE -
                                        get_inline_xattr_addrs(inode)]);
}

static inline int inline_xattr_size(struct inode *inode)
{
        return get_inline_xattr_addrs(inode) * sizeof(__le32);
}

static inline int f2fs_has_inline_data(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_INLINE_DATA);
}

static inline int f2fs_exist_data(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_DATA_EXIST);
}

static inline int f2fs_has_inline_dots(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_INLINE_DOTS);
}

static inline bool f2fs_is_pinned_file(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_PIN_FILE);
}

static inline bool f2fs_is_atomic_file(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_ATOMIC_FILE);
}

static inline bool f2fs_is_commit_atomic_write(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_ATOMIC_COMMIT);
}

static inline bool f2fs_is_volatile_file(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_VOLATILE_FILE);
}

static inline bool f2fs_is_first_block_written(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_FIRST_BLOCK_WRITTEN);
}

static inline bool f2fs_is_drop_cache(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_DROP_CACHE);
}

static inline void *inline_data_addr(struct inode *inode, struct page *page)
{
        struct f2fs_inode *ri = F2FS_INODE(page);
        int extra_size = get_extra_isize(inode);

        return (void *)&(ri->i_addr[extra_size + DEF_INLINE_RESERVED_SIZE]);
}

static inline int f2fs_has_inline_dentry(struct inode *inode)
{
        return is_inode_flag_set(inode, FI_INLINE_DENTRY);
}

static inline int is_file(struct inode *inode, int type)
{
        return F2FS_I(inode)->i_advise & type;
}

static inline void set_file(struct inode *inode, int type)
{
        F2FS_I(inode)->i_advise |= type;
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline void clear_file(struct inode *inode, int type)
{
        F2FS_I(inode)->i_advise &= ~type;
        f2fs_mark_inode_dirty_sync(inode, true);
}

static inline bool f2fs_skip_inode_update(struct inode *inode, int dsync)
{
        bool ret;

        if (dsync) {
                struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

                spin_lock(&sbi->inode_lock[DIRTY_META]);
                ret = list_empty(&F2FS_I(inode)->gdirty_list);
                spin_unlock(&sbi->inode_lock[DIRTY_META]);
                return ret;
        }
        if (!is_inode_flag_set(inode, FI_AUTO_RECOVER) ||
                        file_keep_isize(inode) ||
                        i_size_read(inode) & ~PAGE_MASK)
                return false;

        if (!timespec_equal(F2FS_I(inode)->i_disk_time, &inode->i_atime))
                return false;
        if (!timespec_equal(F2FS_I(inode)->i_disk_time + 1, &inode->i_ctime))
                return false;
        if (!timespec_equal(F2FS_I(inode)->i_disk_time + 2, &inode->i_mtime))
                return false;
        if (!timespec_equal(F2FS_I(inode)->i_disk_time + 3,
                                                &F2FS_I(inode)->i_crtime))
                return false;

        down_read(&F2FS_I(inode)->i_sem);
        ret = F2FS_I(inode)->last_disk_size == i_size_read(inode);
        up_read(&F2FS_I(inode)->i_sem);

        return ret;
}

static inline bool f2fs_readonly(struct super_block *sb)
{
        return sb_rdonly(sb);
}

static inline bool f2fs_cp_error(struct f2fs_sb_info *sbi)
{
        return is_set_ckpt_flags(sbi, CP_ERROR_FLAG);
}

static inline bool is_dot_dotdot(const struct qstr *str)
{
        if (str->len == 1 && str->name[0] == '.')
                return true;

        if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
                return true;

        return false;
}

static inline bool f2fs_may_extent_tree(struct inode *inode)
{
        if (!test_opt(F2FS_I_SB(inode), EXTENT_CACHE) ||
                        is_inode_flag_set(inode, FI_NO_EXTENT))
                return false;

        return S_ISREG(inode->i_mode);
}

static inline void *f2fs_kmalloc(struct f2fs_sb_info *sbi,
                                        size_t size, gfp_t flags)
{
#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(sbi, FAULT_KMALLOC)) {
                f2fs_show_injection_info(FAULT_KMALLOC);
                return NULL;
        }
#endif
        return kmalloc(size, flags);
}

static inline void *f2fs_kzalloc(struct f2fs_sb_info *sbi,
                                        size_t size, gfp_t flags)
{
        return f2fs_kmalloc(sbi, size, flags | __GFP_ZERO);
}

static inline void *f2fs_kvmalloc(struct f2fs_sb_info *sbi,
                                        size_t size, gfp_t flags)
{
#ifdef CONFIG_F2FS_FAULT_INJECTION
        if (time_to_inject(sbi, FAULT_KVMALLOC)) {
                f2fs_show_injection_info(FAULT_KVMALLOC);
                return NULL;
        }
#endif
        return kvmalloc(size, flags);
}

static inline void *f2fs_kvzalloc(struct f2fs_sb_info *sbi,
                                        size_t size, gfp_t flags)
{
        return f2fs_kvmalloc(sbi, size, flags | __GFP_ZERO);
}

static inline int get_extra_isize(struct inode *inode)
{
        return F2FS_I(inode)->i_extra_isize / sizeof(__le32);
}

static inline int get_inline_xattr_addrs(struct inode *inode)
{
        return F2FS_I(inode)->i_inline_xattr_size;
}

#define get_inode_mode(i) \
        ((is_inode_flag_set(i, FI_ACL_MODE)) ? \
         (F2FS_I(i)->i_acl_mode) : ((i)->i_mode))

#define F2FS_TOTAL_EXTRA_ATTR_SIZE                      \
        (offsetof(struct f2fs_inode, i_extra_end) -     \
        offsetof(struct f2fs_inode, i_extra_isize))     \

#define F2FS_OLD_ATTRIBUTE_SIZE (offsetof(struct f2fs_inode, i_addr))
#define F2FS_FITS_IN_INODE(f2fs_inode, extra_isize, field)              \
                ((offsetof(typeof(*f2fs_inode), field) +        \
                sizeof((f2fs_inode)->field))                    \
                <= (F2FS_OLD_ATTRIBUTE_SIZE + extra_isize))     \

static inline void f2fs_reset_iostat(struct f2fs_sb_info *sbi)
{
        int i;

        spin_lock(&sbi->iostat_lock);
        for (i = 0; i < NR_IO_TYPE; i++)
                sbi->write_iostat[i] = 0;
        spin_unlock(&sbi->iostat_lock);
}

static inline void f2fs_update_iostat(struct f2fs_sb_info *sbi,
                        enum iostat_type type, unsigned long long io_bytes)
{
        if (!sbi->iostat_enable)
                return;
        spin_lock(&sbi->iostat_lock);
        sbi->write_iostat[type] += io_bytes;

        if (type == APP_WRITE_IO || type == APP_DIRECT_IO)
                sbi->write_iostat[APP_BUFFERED_IO] =
                        sbi->write_iostat[APP_WRITE_IO] -
                        sbi->write_iostat[APP_DIRECT_IO];
        spin_unlock(&sbi->iostat_lock);
}

/*
 * file.c
 */
int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync);
void truncate_data_blocks(struct dnode_of_data *dn);
int truncate_blocks(struct inode *inode, u64 from, bool lock);
int f2fs_truncate(struct inode *inode);
int f2fs_getattr(const struct path *path, struct kstat *stat,
                        u32 request_mask, unsigned int flags);
int f2fs_setattr(struct dentry *dentry, struct iattr *attr);
int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end);
void truncate_data_blocks_range(struct dnode_of_data *dn, int count);
int f2fs_precache_extents(struct inode *inode);
long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
int f2fs_pin_file_control(struct inode *inode, bool inc);

/*
 * inode.c
 */
void f2fs_set_inode_flags(struct inode *inode);
bool f2fs_inode_chksum_verify(struct f2fs_sb_info *sbi, struct page *page);
void f2fs_inode_chksum_set(struct f2fs_sb_info *sbi, struct page *page);
struct inode *f2fs_iget(struct super_block *sb, unsigned long ino);
struct inode *f2fs_iget_retry(struct super_block *sb, unsigned long ino);
int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink);
void update_inode(struct inode *inode, struct page *node_page);
void update_inode_page(struct inode *inode);
int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc);
void f2fs_evict_inode(struct inode *inode);
void handle_failed_inode(struct inode *inode);

/*
 * namei.c
 */
int update_extension_list(struct f2fs_sb_info *sbi, const char *name,
                                                        bool hot, bool set);
struct dentry *f2fs_get_parent(struct dentry *child);

/*
 * dir.c
 */
void set_de_type(struct f2fs_dir_entry *de, umode_t mode);
unsigned char get_de_type(struct f2fs_dir_entry *de);
struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname,
                        f2fs_hash_t namehash, int *max_slots,
                        struct f2fs_dentry_ptr *d);
int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
                        unsigned int start_pos, struct fscrypt_str *fstr);
void do_make_empty_dir(struct inode *inode, struct inode *parent,
                        struct f2fs_dentry_ptr *d);
struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
                        const struct qstr *new_name,
                        const struct qstr *orig_name, struct page *dpage);
void update_parent_metadata(struct inode *dir, struct inode *inode,
                        unsigned int current_depth);
int room_for_filename(const void *bitmap, int slots, int max_slots);
void f2fs_drop_nlink(struct inode *dir, struct inode *inode);
struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
                        struct fscrypt_name *fname, struct page **res_page);
struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
                        const struct qstr *child, struct page **res_page);
struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p);
ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
                        struct page **page);
void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
                        struct page *page, struct inode *inode);
void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
                        const struct qstr *name, f2fs_hash_t name_hash,
                        unsigned int bit_pos);
int f2fs_add_regular_entry(struct inode *dir, const struct qstr *new_name,
                        const struct qstr *orig_name,
                        struct inode *inode, nid_t ino, umode_t mode);
int __f2fs_do_add_link(struct inode *dir, struct fscrypt_name *fname,
                        struct inode *inode, nid_t ino, umode_t mode);
int __f2fs_add_link(struct inode *dir, const struct qstr *name,
                        struct inode *inode, nid_t ino, umode_t mode);
void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
                        struct inode *dir, struct inode *inode);
int f2fs_do_tmpfile(struct inode *inode, struct inode *dir);
bool f2fs_empty_dir(struct inode *dir);

static inline int f2fs_add_link(struct dentry *dentry, struct inode *inode)
{
        return __f2fs_add_link(d_inode(dentry->d_parent), &dentry->d_name,
                                inode, inode->i_ino, inode->i_mode);
}

/*
 * super.c
 */
int f2fs_inode_dirtied(struct inode *inode, bool sync);
void f2fs_inode_synced(struct inode *inode);
int f2fs_enable_quota_files(struct f2fs_sb_info *sbi, bool rdonly);
void f2fs_quota_off_umount(struct super_block *sb);
int f2fs_commit_super(struct f2fs_sb_info *sbi, bool recover);
int f2fs_sync_fs(struct super_block *sb, int sync);
extern __printf(3, 4)
void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...);
int sanity_check_ckpt(struct f2fs_sb_info *sbi);

/*
 * hash.c
 */
f2fs_hash_t f2fs_dentry_hash(const struct qstr *name_info,
                                struct fscrypt_name *fname);

/*
 * node.c
 */
struct dnode_of_data;
struct node_info;

bool available_free_memory(struct f2fs_sb_info *sbi, int type);
int need_dentry_mark(struct f2fs_sb_info *sbi, nid_t nid);
bool is_checkpointed_node(struct f2fs_sb_info *sbi, nid_t nid);
bool need_inode_block_update(struct f2fs_sb_info *sbi, nid_t ino);
void get_node_info(struct f2fs_sb_info *sbi, nid_t nid, struct node_info *ni);
pgoff_t get_next_page_offset(struct dnode_of_data *dn, pgoff_t pgofs);
int get_dnode_of_data(struct dnode_of_data *dn, pgoff_t index, int mode);
int truncate_inode_blocks(struct inode *inode, pgoff_t from);
int truncate_xattr_node(struct inode *inode);
int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino);
int remove_inode_page(struct inode *inode);
struct page *new_inode_page(struct inode *inode);
struct page *new_node_page(struct dnode_of_data *dn, unsigned int ofs);
void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid);
struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid);
struct page *get_node_page_ra(struct page *parent, int start);
void move_node_page(struct page *node_page, int gc_type);
int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
                        struct writeback_control *wbc, bool atomic);
int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc,
                        bool do_balance, enum iostat_type io_type);
void build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount);
bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid);
void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid);
void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid);
int try_to_free_nids(struct f2fs_sb_info *sbi, int nr_shrink);
void recover_inline_xattr(struct inode *inode, struct page *page);
int recover_xattr_data(struct inode *inode, struct page *page);
int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page);
void restore_node_summary(struct f2fs_sb_info *sbi,
                        unsigned int segno, struct f2fs_summary_block *sum);
void flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc);
int build_node_manager(struct f2fs_sb_info *sbi);
void destroy_node_manager(struct f2fs_sb_info *sbi);
int __init create_node_manager_caches(void);
void destroy_node_manager_caches(void);

/*
 * segment.c
 */
bool need_SSR(struct f2fs_sb_info *sbi);
void register_inmem_page(struct inode *inode, struct page *page);
void drop_inmem_pages_all(struct f2fs_sb_info *sbi);
void drop_inmem_pages(struct inode *inode);
void drop_inmem_page(struct inode *inode, struct page *page);
int commit_inmem_pages(struct inode *inode);
void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need);
void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi);
int f2fs_issue_flush(struct f2fs_sb_info *sbi, nid_t ino);
int create_flush_cmd_control(struct f2fs_sb_info *sbi);
int f2fs_flush_device_cache(struct f2fs_sb_info *sbi);
void destroy_flush_cmd_control(struct f2fs_sb_info *sbi, bool free);
void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr);
bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr);
void init_discard_policy(struct discard_policy *dpolicy, int discard_type,
                                                unsigned int granularity);
void drop_discard_cmd(struct f2fs_sb_info *sbi);
void stop_discard_thread(struct f2fs_sb_info *sbi);
bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc);
void release_discard_addrs(struct f2fs_sb_info *sbi);
int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra);
void allocate_new_segments(struct f2fs_sb_info *sbi);
int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range);
bool exist_trim_candidates(struct f2fs_sb_info *sbi, struct cp_control *cpc);
struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno);
void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr);
void write_meta_page(struct f2fs_sb_info *sbi, struct page *page,
                                                enum iostat_type io_type);
void write_node_page(unsigned int nid, struct f2fs_io_info *fio);
void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio);
int rewrite_data_page(struct f2fs_io_info *fio);
void __f2fs_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
                        block_t old_blkaddr, block_t new_blkaddr,
                        bool recover_curseg, bool recover_newaddr);
void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
                        block_t old_addr, block_t new_addr,
                        unsigned char version, bool recover_curseg,
                        bool recover_newaddr);
void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
                        block_t old_blkaddr, block_t *new_blkaddr,
                        struct f2fs_summary *sum, int type,
                        struct f2fs_io_info *fio, bool add_list);
void f2fs_wait_on_page_writeback(struct page *page,
                        enum page_type type, bool ordered);
void f2fs_wait_on_block_writeback(struct f2fs_sb_info *sbi, block_t blkaddr);
void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk);
void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk);
int lookup_journal_in_cursum(struct f2fs_journal *journal, int type,
                        unsigned int val, int alloc);
void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc);
int build_segment_manager(struct f2fs_sb_info *sbi);
void destroy_segment_manager(struct f2fs_sb_info *sbi);
int __init create_segment_manager_caches(void);
void destroy_segment_manager_caches(void);
int rw_hint_to_seg_type(enum rw_hint hint);
enum rw_hint io_type_to_rw_hint(struct f2fs_sb_info *sbi, enum page_type type,
                                enum temp_type temp);

/*
 * checkpoint.c
 */
void f2fs_stop_checkpoint(struct f2fs_sb_info *sbi, bool end_io);
struct page *grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index);
struct page *get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index);
struct page *get_tmp_page(struct f2fs_sb_info *sbi, pgoff_t index);
bool is_valid_blkaddr(struct f2fs_sb_info *sbi, block_t blkaddr, int type);
int ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
                        int type, bool sync);
void ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index);
long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
                        long nr_to_write, enum iostat_type io_type);
void add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type);
void remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type);
void release_ino_entry(struct f2fs_sb_info *sbi, bool all);
bool exist_written_data(struct f2fs_sb_info *sbi, nid_t ino, int mode);
void set_dirty_device(struct f2fs_sb_info *sbi, nid_t ino,
                                        unsigned int devidx, int type);
bool is_dirty_device(struct f2fs_sb_info *sbi, nid_t ino,
                                        unsigned int devidx, int type);
int f2fs_sync_inode_meta(struct f2fs_sb_info *sbi);
int acquire_orphan_inode(struct f2fs_sb_info *sbi);
void release_orphan_inode(struct f2fs_sb_info *sbi);
void add_orphan_inode(struct inode *inode);
void remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino);
int recover_orphan_inodes(struct f2fs_sb_info *sbi);
int get_valid_checkpoint(struct f2fs_sb_info *sbi);
void update_dirty_page(struct inode *inode, struct page *page);
void remove_dirty_inode(struct inode *inode);
int sync_dirty_inodes(struct f2fs_sb_info *sbi, enum inode_type type);
int write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc);
void init_ino_entry_info(struct f2fs_sb_info *sbi);
int __init create_checkpoint_caches(void);
void destroy_checkpoint_caches(void);

/*
 * data.c
 */
void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type);
void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
                                struct inode *inode, nid_t ino, pgoff_t idx,
                                enum page_type type);
void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi);
int f2fs_submit_page_bio(struct f2fs_io_info *fio);
int f2fs_submit_page_write(struct f2fs_io_info *fio);
struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
                        block_t blk_addr, struct bio *bio);
int f2fs_target_device_index(struct f2fs_sb_info *sbi, block_t blkaddr);
void set_data_blkaddr(struct dnode_of_data *dn);
void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr);
int reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count);
int reserve_new_block(struct dnode_of_data *dn);
int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index);
int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from);
int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index);
struct page *get_read_data_page(struct inode *inode, pgoff_t index,
                        int op_flags, bool for_write);
struct page *find_data_page(struct inode *inode, pgoff_t index);
struct page *get_lock_data_page(struct inode *inode, pgoff_t index,
                        bool for_write);
struct page *get_new_data_page(struct inode *inode,
                        struct page *ipage, pgoff_t index, bool new_i_size);
int do_write_data_page(struct f2fs_io_info *fio);
int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
                        int create, int flag);
int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                        u64 start, u64 len);
bool should_update_inplace(struct inode *inode, struct f2fs_io_info *fio);
bool should_update_outplace(struct inode *inode, struct f2fs_io_info *fio);
void f2fs_set_page_dirty_nobuffers(struct page *page);
int __f2fs_write_data_pages(struct address_space *mapping,
                                                struct writeback_control *wbc,
                                                enum iostat_type io_type);
void f2fs_invalidate_page(struct page *page, unsigned int offset,
                        unsigned int length);
int f2fs_release_page(struct page *page, gfp_t wait);
#ifdef CONFIG_MIGRATION
int f2fs_migrate_page(struct address_space *mapping, struct page *newpage,
                        struct page *page, enum migrate_mode mode);
#endif
bool f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len);

/*
 * gc.c
 */
int start_gc_thread(struct f2fs_sb_info *sbi);
void stop_gc_thread(struct f2fs_sb_info *sbi);
block_t start_bidx_of_node(unsigned int node_ofs, struct inode *inode);
int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, bool background,
                        unsigned int segno);
void build_gc_manager(struct f2fs_sb_info *sbi);

/*
 * recovery.c
 */
int recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only);
bool space_for_roll_forward(struct f2fs_sb_info *sbi);

/*
 * debug.c
 */
#ifdef CONFIG_F2FS_STAT_FS
struct f2fs_stat_info {
        struct list_head stat_list;
        struct f2fs_sb_info *sbi;
        int all_area_segs, sit_area_segs, nat_area_segs, ssa_area_segs;
        int main_area_segs, main_area_sections, main_area_zones;
        unsigned long long hit_largest, hit_cached, hit_rbtree;
        unsigned long long hit_total, total_ext;
        int ext_tree, zombie_tree, ext_node;
        int ndirty_node, ndirty_dent, ndirty_meta, ndirty_imeta;
        int ndirty_data, ndirty_qdata;
        int inmem_pages;
        unsigned int ndirty_dirs, ndirty_files, nquota_files, ndirty_all;
        int nats, dirty_nats, sits, dirty_sits;
        int free_nids, avail_nids, alloc_nids;
        int total_count, utilization;
        int bg_gc, nr_wb_cp_data, nr_wb_data;
        int nr_flushing, nr_flushed, flush_list_empty;
        int nr_discarding, nr_discarded;
        int nr_discard_cmd;
        unsigned int undiscard_blks;
        int inline_xattr, inline_inode, inline_dir, append, update, orphans;
        int aw_cnt, max_aw_cnt, vw_cnt, max_vw_cnt;
        unsigned int valid_count, valid_node_count, valid_inode_count, discard_blks;
        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, cp_count, bg_cp_count;
        int tot_segs, node_segs, data_segs, free_segs, free_secs;
        int bg_node_segs, bg_data_segs;
        int tot_blks, data_blks, node_blks;
        int bg_data_blks, bg_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 int inplace_count;
        unsigned long long base_mem, cache_mem, page_mem;
};

static inline struct f2fs_stat_info *F2FS_STAT(struct f2fs_sb_info *sbi)
{
        return (struct f2fs_stat_info *)sbi->stat_info;
}

#define stat_inc_cp_count(si)           ((si)->cp_count++)
#define stat_inc_bg_cp_count(si)        ((si)->bg_cp_count++)
#define stat_inc_call_count(si)         ((si)->call_count++)
#define stat_inc_bggc_count(sbi)        ((sbi)->bg_gc++)
#define stat_inc_dirty_inode(sbi, type) ((sbi)->ndirty_inode[type]++)
#define stat_dec_dirty_inode(sbi, type) ((sbi)->ndirty_inode[type]--)
#define stat_inc_total_hit(sbi)         (atomic64_inc(&(sbi)->total_hit_ext))
#define stat_inc_rbtree_node_hit(sbi)   (atomic64_inc(&(sbi)->read_hit_rbtree))
#define stat_inc_largest_node_hit(sbi)  (atomic64_inc(&(sbi)->read_hit_largest))
#define stat_inc_cached_node_hit(sbi)   (atomic64_inc(&(sbi)->read_hit_cached))
#define stat_inc_inline_xattr(inode)                                    \
        do {                                                            \
                if (f2fs_has_inline_xattr(inode))                       \
                        (atomic_inc(&F2FS_I_SB(inode)->inline_xattr));  \
        } while (0)
#define stat_dec_inline_xattr(inode)                                    \
        do {                                                            \
                if (f2fs_has_inline_xattr(inode))                       \
                        (atomic_dec(&F2FS_I_SB(inode)->inline_xattr));  \
        } while (0)
#define stat_inc_inline_inode(inode)                                    \
        do {                                                            \
                if (f2fs_has_inline_data(inode))                        \
                        (atomic_inc(&F2FS_I_SB(inode)->inline_inode));  \
        } while (0)
#define stat_dec_inline_inode(inode)                                    \
        do {                                                            \
                if (f2fs_has_inline_data(inode))                        \
                        (atomic_dec(&F2FS_I_SB(inode)->inline_inode));  \