Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / f2fs / segment.h
diff --git a/kernel/fs/f2fs/segment.h b/kernel/fs/f2fs/segment.h
new file mode 100644 (file)
index 0000000..85d7fa7
--- /dev/null
@@ -0,0 +1,751 @@
+/*
+ * fs/f2fs/segment.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.
+ */
+#include <linux/blkdev.h>
+
+/* constant macro */
+#define NULL_SEGNO                     ((unsigned int)(~0))
+#define NULL_SECNO                     ((unsigned int)(~0))
+
+#define DEF_RECLAIM_PREFREE_SEGMENTS   5       /* 5% over total segments */
+
+/* L: Logical segment # in volume, R: Relative segment # in main area */
+#define GET_L2R_SEGNO(free_i, segno)   (segno - free_i->start_segno)
+#define GET_R2L_SEGNO(free_i, segno)   (segno + free_i->start_segno)
+
+#define IS_DATASEG(t)  (t <= CURSEG_COLD_DATA)
+#define IS_NODESEG(t)  (t >= CURSEG_HOT_NODE)
+
+#define IS_CURSEG(sbi, seg)                                            \
+       ((seg == CURSEG_I(sbi, CURSEG_HOT_DATA)->segno) ||      \
+        (seg == CURSEG_I(sbi, CURSEG_WARM_DATA)->segno) ||     \
+        (seg == CURSEG_I(sbi, CURSEG_COLD_DATA)->segno) ||     \
+        (seg == CURSEG_I(sbi, CURSEG_HOT_NODE)->segno) ||      \
+        (seg == CURSEG_I(sbi, CURSEG_WARM_NODE)->segno) ||     \
+        (seg == CURSEG_I(sbi, CURSEG_COLD_NODE)->segno))
+
+#define IS_CURSEC(sbi, secno)                                          \
+       ((secno == CURSEG_I(sbi, CURSEG_HOT_DATA)->segno /              \
+         sbi->segs_per_sec) || \
+        (secno == CURSEG_I(sbi, CURSEG_WARM_DATA)->segno /             \
+         sbi->segs_per_sec) || \
+        (secno == CURSEG_I(sbi, CURSEG_COLD_DATA)->segno /             \
+         sbi->segs_per_sec) || \
+        (secno == CURSEG_I(sbi, CURSEG_HOT_NODE)->segno /              \
+         sbi->segs_per_sec) || \
+        (secno == CURSEG_I(sbi, CURSEG_WARM_NODE)->segno /             \
+         sbi->segs_per_sec) || \
+        (secno == CURSEG_I(sbi, CURSEG_COLD_NODE)->segno /             \
+         sbi->segs_per_sec))   \
+
+#define MAIN_BLKADDR(sbi)      (SM_I(sbi)->main_blkaddr)
+#define SEG0_BLKADDR(sbi)      (SM_I(sbi)->seg0_blkaddr)
+
+#define MAIN_SEGS(sbi) (SM_I(sbi)->main_segments)
+#define MAIN_SECS(sbi) (sbi->total_sections)
+
+#define TOTAL_SEGS(sbi)        (SM_I(sbi)->segment_count)
+#define TOTAL_BLKS(sbi)        (TOTAL_SEGS(sbi) << sbi->log_blocks_per_seg)
+
+#define MAX_BLKADDR(sbi)       (SEG0_BLKADDR(sbi) + TOTAL_BLKS(sbi))
+#define SEGMENT_SIZE(sbi)      (1ULL << (sbi->log_blocksize +          \
+                                       sbi->log_blocks_per_seg))
+
+#define START_BLOCK(sbi, segno)        (SEG0_BLKADDR(sbi) +                    \
+        (GET_R2L_SEGNO(FREE_I(sbi), segno) << sbi->log_blocks_per_seg))
+
+#define NEXT_FREE_BLKADDR(sbi, curseg)                                 \
+       (START_BLOCK(sbi, curseg->segno) + curseg->next_blkoff)
+
+#define GET_SEGOFF_FROM_SEG0(sbi, blk_addr)    ((blk_addr) - SEG0_BLKADDR(sbi))
+#define GET_SEGNO_FROM_SEG0(sbi, blk_addr)                             \
+       (GET_SEGOFF_FROM_SEG0(sbi, blk_addr) >> sbi->log_blocks_per_seg)
+#define GET_BLKOFF_FROM_SEG0(sbi, blk_addr)                            \
+       (GET_SEGOFF_FROM_SEG0(sbi, blk_addr) & (sbi->blocks_per_seg - 1))
+
+#define GET_SEGNO(sbi, blk_addr)                                       \
+       (((blk_addr == NULL_ADDR) || (blk_addr == NEW_ADDR)) ?          \
+       NULL_SEGNO : GET_L2R_SEGNO(FREE_I(sbi),                 \
+               GET_SEGNO_FROM_SEG0(sbi, blk_addr)))
+#define GET_SECNO(sbi, segno)                                  \
+       ((segno) / sbi->segs_per_sec)
+#define GET_ZONENO_FROM_SEGNO(sbi, segno)                              \
+       ((segno / sbi->segs_per_sec) / sbi->secs_per_zone)
+
+#define GET_SUM_BLOCK(sbi, segno)                              \
+       ((sbi->sm_info->ssa_blkaddr) + segno)
+
+#define GET_SUM_TYPE(footer) ((footer)->entry_type)
+#define SET_SUM_TYPE(footer, type) ((footer)->entry_type = type)
+
+#define SIT_ENTRY_OFFSET(sit_i, segno)                                 \
+       (segno % sit_i->sents_per_block)
+#define SIT_BLOCK_OFFSET(segno)                                        \
+       (segno / SIT_ENTRY_PER_BLOCK)
+#define        START_SEGNO(segno)              \
+       (SIT_BLOCK_OFFSET(segno) * SIT_ENTRY_PER_BLOCK)
+#define SIT_BLK_CNT(sbi)                       \
+       ((MAIN_SEGS(sbi) + SIT_ENTRY_PER_BLOCK - 1) / SIT_ENTRY_PER_BLOCK)
+#define f2fs_bitmap_size(nr)                   \
+       (BITS_TO_LONGS(nr) * sizeof(unsigned long))
+
+#define SECTOR_FROM_BLOCK(blk_addr)                                    \
+       (((sector_t)blk_addr) << F2FS_LOG_SECTORS_PER_BLOCK)
+#define SECTOR_TO_BLOCK(sectors)                                       \
+       (sectors >> F2FS_LOG_SECTORS_PER_BLOCK)
+#define MAX_BIO_BLOCKS(sbi)                                            \
+       ((int)min((int)max_hw_blocks(sbi), BIO_MAX_PAGES))
+
+/*
+ * indicate a block allocation direction: RIGHT and LEFT.
+ * RIGHT means allocating new sections towards the end of volume.
+ * LEFT means the opposite direction.
+ */
+enum {
+       ALLOC_RIGHT = 0,
+       ALLOC_LEFT
+};
+
+/*
+ * In the victim_sel_policy->alloc_mode, there are two block allocation modes.
+ * LFS writes data sequentially with cleaning operations.
+ * SSR (Slack Space Recycle) reuses obsolete space without cleaning operations.
+ */
+enum {
+       LFS = 0,
+       SSR
+};
+
+/*
+ * In the victim_sel_policy->gc_mode, there are two gc, aka cleaning, modes.
+ * GC_CB is based on cost-benefit algorithm.
+ * GC_GREEDY is based on greedy algorithm.
+ */
+enum {
+       GC_CB = 0,
+       GC_GREEDY
+};
+
+/*
+ * BG_GC means the background cleaning job.
+ * FG_GC means the on-demand cleaning job.
+ */
+enum {
+       BG_GC = 0,
+       FG_GC
+};
+
+/* for a function parameter to select a victim segment */
+struct victim_sel_policy {
+       int alloc_mode;                 /* LFS or SSR */
+       int gc_mode;                    /* GC_CB or GC_GREEDY */
+       unsigned long *dirty_segmap;    /* dirty segment bitmap */
+       unsigned int max_search;        /* maximum # of segments to search */
+       unsigned int offset;            /* last scanned bitmap offset */
+       unsigned int ofs_unit;          /* bitmap search unit */
+       unsigned int min_cost;          /* minimum cost */
+       unsigned int min_segno;         /* segment # having min. cost */
+};
+
+struct seg_entry {
+       unsigned short valid_blocks;    /* # of valid blocks */
+       unsigned char *cur_valid_map;   /* validity bitmap of blocks */
+       /*
+        * # of valid blocks and the validity bitmap stored in the the last
+        * checkpoint pack. This information is used by the SSR mode.
+        */
+       unsigned short ckpt_valid_blocks;
+       unsigned char *ckpt_valid_map;
+       unsigned char type;             /* segment type like CURSEG_XXX_TYPE */
+       unsigned long long mtime;       /* modification time of the segment */
+};
+
+struct sec_entry {
+       unsigned int valid_blocks;      /* # of valid blocks in a section */
+};
+
+struct segment_allocation {
+       void (*allocate_segment)(struct f2fs_sb_info *, int, bool);
+};
+
+struct inmem_pages {
+       struct list_head list;
+       struct page *page;
+};
+
+struct sit_info {
+       const struct segment_allocation *s_ops;
+
+       block_t sit_base_addr;          /* start block address of SIT area */
+       block_t sit_blocks;             /* # of blocks used by SIT area */
+       block_t written_valid_blocks;   /* # of valid blocks in main area */
+       char *sit_bitmap;               /* SIT bitmap pointer */
+       unsigned int bitmap_size;       /* SIT bitmap size */
+
+       unsigned long *tmp_map;                 /* bitmap for temporal use */
+       unsigned long *dirty_sentries_bitmap;   /* bitmap for dirty sentries */
+       unsigned int dirty_sentries;            /* # of dirty sentries */
+       unsigned int sents_per_block;           /* # of SIT entries per block */
+       struct mutex sentry_lock;               /* to protect SIT cache */
+       struct seg_entry *sentries;             /* SIT segment-level cache */
+       struct sec_entry *sec_entries;          /* SIT section-level cache */
+
+       /* for cost-benefit algorithm in cleaning procedure */
+       unsigned long long elapsed_time;        /* elapsed time after mount */
+       unsigned long long mounted_time;        /* mount time */
+       unsigned long long min_mtime;           /* min. modification time */
+       unsigned long long max_mtime;           /* max. modification time */
+};
+
+struct free_segmap_info {
+       unsigned int start_segno;       /* start segment number logically */
+       unsigned int free_segments;     /* # of free segments */
+       unsigned int free_sections;     /* # of free sections */
+       spinlock_t segmap_lock;         /* free segmap lock */
+       unsigned long *free_segmap;     /* free segment bitmap */
+       unsigned long *free_secmap;     /* free section bitmap */
+};
+
+/* Notice: The order of dirty type is same with CURSEG_XXX in f2fs.h */
+enum dirty_type {
+       DIRTY_HOT_DATA,         /* dirty segments assigned as hot data logs */
+       DIRTY_WARM_DATA,        /* dirty segments assigned as warm data logs */
+       DIRTY_COLD_DATA,        /* dirty segments assigned as cold data logs */
+       DIRTY_HOT_NODE,         /* dirty segments assigned as hot node logs */
+       DIRTY_WARM_NODE,        /* dirty segments assigned as warm node logs */
+       DIRTY_COLD_NODE,        /* dirty segments assigned as cold node logs */
+       DIRTY,                  /* to count # of dirty segments */
+       PRE,                    /* to count # of entirely obsolete segments */
+       NR_DIRTY_TYPE
+};
+
+struct dirty_seglist_info {
+       const struct victim_selection *v_ops;   /* victim selction operation */
+       unsigned long *dirty_segmap[NR_DIRTY_TYPE];
+       struct mutex seglist_lock;              /* lock for segment bitmaps */
+       int nr_dirty[NR_DIRTY_TYPE];            /* # of dirty segments */
+       unsigned long *victim_secmap;           /* background GC victims */
+};
+
+/* victim selection function for cleaning and SSR */
+struct victim_selection {
+       int (*get_victim)(struct f2fs_sb_info *, unsigned int *,
+                                                       int, int, char);
+};
+
+/* for active log information */
+struct curseg_info {
+       struct mutex curseg_mutex;              /* lock for consistency */
+       struct f2fs_summary_block *sum_blk;     /* cached summary block */
+       unsigned char alloc_type;               /* current allocation type */
+       unsigned int segno;                     /* current segment number */
+       unsigned short next_blkoff;             /* next block offset to write */
+       unsigned int zone;                      /* current zone number */
+       unsigned int next_segno;                /* preallocated segment */
+};
+
+struct sit_entry_set {
+       struct list_head set_list;      /* link with all sit sets */
+       unsigned int start_segno;       /* start segno of sits in set */
+       unsigned int entry_cnt;         /* the # of sit entries in set */
+};
+
+/*
+ * inline functions
+ */
+static inline struct curseg_info *CURSEG_I(struct f2fs_sb_info *sbi, int type)
+{
+       return (struct curseg_info *)(SM_I(sbi)->curseg_array + type);
+}
+
+static inline struct seg_entry *get_seg_entry(struct f2fs_sb_info *sbi,
+                                               unsigned int segno)
+{
+       struct sit_info *sit_i = SIT_I(sbi);
+       return &sit_i->sentries[segno];
+}
+
+static inline struct sec_entry *get_sec_entry(struct f2fs_sb_info *sbi,
+                                               unsigned int segno)
+{
+       struct sit_info *sit_i = SIT_I(sbi);
+       return &sit_i->sec_entries[GET_SECNO(sbi, segno)];
+}
+
+static inline unsigned int get_valid_blocks(struct f2fs_sb_info *sbi,
+                               unsigned int segno, int section)
+{
+       /*
+        * In order to get # of valid blocks in a section instantly from many
+        * segments, f2fs manages two counting structures separately.
+        */
+       if (section > 1)
+               return get_sec_entry(sbi, segno)->valid_blocks;
+       else
+               return get_seg_entry(sbi, segno)->valid_blocks;
+}
+
+static inline void seg_info_from_raw_sit(struct seg_entry *se,
+                                       struct f2fs_sit_entry *rs)
+{
+       se->valid_blocks = GET_SIT_VBLOCKS(rs);
+       se->ckpt_valid_blocks = GET_SIT_VBLOCKS(rs);
+       memcpy(se->cur_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
+       memcpy(se->ckpt_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
+       se->type = GET_SIT_TYPE(rs);
+       se->mtime = le64_to_cpu(rs->mtime);
+}
+
+static inline void seg_info_to_raw_sit(struct seg_entry *se,
+                                       struct f2fs_sit_entry *rs)
+{
+       unsigned short raw_vblocks = (se->type << SIT_VBLOCKS_SHIFT) |
+                                       se->valid_blocks;
+       rs->vblocks = cpu_to_le16(raw_vblocks);
+       memcpy(rs->valid_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
+       memcpy(se->ckpt_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
+       se->ckpt_valid_blocks = se->valid_blocks;
+       rs->mtime = cpu_to_le64(se->mtime);
+}
+
+static inline unsigned int find_next_inuse(struct free_segmap_info *free_i,
+               unsigned int max, unsigned int segno)
+{
+       unsigned int ret;
+       spin_lock(&free_i->segmap_lock);
+       ret = find_next_bit(free_i->free_segmap, max, segno);
+       spin_unlock(&free_i->segmap_lock);
+       return ret;
+}
+
+static inline void __set_free(struct f2fs_sb_info *sbi, unsigned int segno)
+{
+       struct free_segmap_info *free_i = FREE_I(sbi);
+       unsigned int secno = segno / sbi->segs_per_sec;
+       unsigned int start_segno = secno * sbi->segs_per_sec;
+       unsigned int next;
+
+       spin_lock(&free_i->segmap_lock);
+       clear_bit(segno, free_i->free_segmap);
+       free_i->free_segments++;
+
+       next = find_next_bit(free_i->free_segmap,
+                       start_segno + sbi->segs_per_sec, start_segno);
+       if (next >= start_segno + sbi->segs_per_sec) {
+               clear_bit(secno, free_i->free_secmap);
+               free_i->free_sections++;
+       }
+       spin_unlock(&free_i->segmap_lock);
+}
+
+static inline void __set_inuse(struct f2fs_sb_info *sbi,
+               unsigned int segno)
+{
+       struct free_segmap_info *free_i = FREE_I(sbi);
+       unsigned int secno = segno / sbi->segs_per_sec;
+       set_bit(segno, free_i->free_segmap);
+       free_i->free_segments--;
+       if (!test_and_set_bit(secno, free_i->free_secmap))
+               free_i->free_sections--;
+}
+
+static inline void __set_test_and_free(struct f2fs_sb_info *sbi,
+               unsigned int segno)
+{
+       struct free_segmap_info *free_i = FREE_I(sbi);
+       unsigned int secno = segno / sbi->segs_per_sec;
+       unsigned int start_segno = secno * sbi->segs_per_sec;
+       unsigned int next;
+
+       spin_lock(&free_i->segmap_lock);
+       if (test_and_clear_bit(segno, free_i->free_segmap)) {
+               free_i->free_segments++;
+
+               next = find_next_bit(free_i->free_segmap,
+                               start_segno + sbi->segs_per_sec, start_segno);
+               if (next >= start_segno + sbi->segs_per_sec) {
+                       if (test_and_clear_bit(secno, free_i->free_secmap))
+                               free_i->free_sections++;
+               }
+       }
+       spin_unlock(&free_i->segmap_lock);
+}
+
+static inline void __set_test_and_inuse(struct f2fs_sb_info *sbi,
+               unsigned int segno)
+{
+       struct free_segmap_info *free_i = FREE_I(sbi);
+       unsigned int secno = segno / sbi->segs_per_sec;
+       spin_lock(&free_i->segmap_lock);
+       if (!test_and_set_bit(segno, free_i->free_segmap)) {
+               free_i->free_segments--;
+               if (!test_and_set_bit(secno, free_i->free_secmap))
+                       free_i->free_sections--;
+       }
+       spin_unlock(&free_i->segmap_lock);
+}
+
+static inline void get_sit_bitmap(struct f2fs_sb_info *sbi,
+               void *dst_addr)
+{
+       struct sit_info *sit_i = SIT_I(sbi);
+       memcpy(dst_addr, sit_i->sit_bitmap, sit_i->bitmap_size);
+}
+
+static inline block_t written_block_count(struct f2fs_sb_info *sbi)
+{
+       return SIT_I(sbi)->written_valid_blocks;
+}
+
+static inline unsigned int free_segments(struct f2fs_sb_info *sbi)
+{
+       return FREE_I(sbi)->free_segments;
+}
+
+static inline int reserved_segments(struct f2fs_sb_info *sbi)
+{
+       return SM_I(sbi)->reserved_segments;
+}
+
+static inline unsigned int free_sections(struct f2fs_sb_info *sbi)
+{
+       return FREE_I(sbi)->free_sections;
+}
+
+static inline unsigned int prefree_segments(struct f2fs_sb_info *sbi)
+{
+       return DIRTY_I(sbi)->nr_dirty[PRE];
+}
+
+static inline unsigned int dirty_segments(struct f2fs_sb_info *sbi)
+{
+       return DIRTY_I(sbi)->nr_dirty[DIRTY_HOT_DATA] +
+               DIRTY_I(sbi)->nr_dirty[DIRTY_WARM_DATA] +
+               DIRTY_I(sbi)->nr_dirty[DIRTY_COLD_DATA] +
+               DIRTY_I(sbi)->nr_dirty[DIRTY_HOT_NODE] +
+               DIRTY_I(sbi)->nr_dirty[DIRTY_WARM_NODE] +
+               DIRTY_I(sbi)->nr_dirty[DIRTY_COLD_NODE];
+}
+
+static inline int overprovision_segments(struct f2fs_sb_info *sbi)
+{
+       return SM_I(sbi)->ovp_segments;
+}
+
+static inline int overprovision_sections(struct f2fs_sb_info *sbi)
+{
+       return ((unsigned int) overprovision_segments(sbi)) / sbi->segs_per_sec;
+}
+
+static inline int reserved_sections(struct f2fs_sb_info *sbi)
+{
+       return ((unsigned int) reserved_segments(sbi)) / sbi->segs_per_sec;
+}
+
+static inline bool need_SSR(struct f2fs_sb_info *sbi)
+{
+       int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
+       int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
+       return free_sections(sbi) <= (node_secs + 2 * dent_secs +
+                                               reserved_sections(sbi) + 1);
+}
+
+static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi, int freed)
+{
+       int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
+       int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
+
+       if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
+               return false;
+
+       return (free_sections(sbi) + freed) <= (node_secs + 2 * dent_secs +
+                                               reserved_sections(sbi));
+}
+
+static inline bool excess_prefree_segs(struct f2fs_sb_info *sbi)
+{
+       return prefree_segments(sbi) > SM_I(sbi)->rec_prefree_segments;
+}
+
+static inline int utilization(struct f2fs_sb_info *sbi)
+{
+       return div_u64((u64)valid_user_blocks(sbi) * 100,
+                                       sbi->user_block_count);
+}
+
+/*
+ * Sometimes f2fs may be better to drop out-of-place update policy.
+ * And, users can control the policy through sysfs entries.
+ * There are five policies with triggering conditions as follows.
+ * F2FS_IPU_FORCE - all the time,
+ * F2FS_IPU_SSR - if SSR mode is activated,
+ * F2FS_IPU_UTIL - if FS utilization is over threashold,
+ * F2FS_IPU_SSR_UTIL - if SSR mode is activated and FS utilization is over
+ *                     threashold,
+ * F2FS_IPU_FSYNC - activated in fsync path only for high performance flash
+ *                     storages. IPU will be triggered only if the # of dirty
+ *                     pages over min_fsync_blocks.
+ * F2FS_IPUT_DISABLE - disable IPU. (=default option)
+ */
+#define DEF_MIN_IPU_UTIL       70
+#define DEF_MIN_FSYNC_BLOCKS   8
+
+enum {
+       F2FS_IPU_FORCE,
+       F2FS_IPU_SSR,
+       F2FS_IPU_UTIL,
+       F2FS_IPU_SSR_UTIL,
+       F2FS_IPU_FSYNC,
+};
+
+static inline bool need_inplace_update(struct inode *inode)
+{
+       struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+       unsigned int policy = SM_I(sbi)->ipu_policy;
+
+       /* IPU can be done only for the user data */
+       if (S_ISDIR(inode->i_mode) || f2fs_is_atomic_file(inode))
+               return false;
+
+       if (policy & (0x1 << F2FS_IPU_FORCE))
+               return true;
+       if (policy & (0x1 << F2FS_IPU_SSR) && need_SSR(sbi))
+               return true;
+       if (policy & (0x1 << F2FS_IPU_UTIL) &&
+                       utilization(sbi) > SM_I(sbi)->min_ipu_util)
+               return true;
+       if (policy & (0x1 << F2FS_IPU_SSR_UTIL) && need_SSR(sbi) &&
+                       utilization(sbi) > SM_I(sbi)->min_ipu_util)
+               return true;
+
+       /* this is only set during fdatasync */
+       if (policy & (0x1 << F2FS_IPU_FSYNC) &&
+                       is_inode_flag_set(F2FS_I(inode), FI_NEED_IPU))
+               return true;
+
+       return false;
+}
+
+static inline unsigned int curseg_segno(struct f2fs_sb_info *sbi,
+               int type)
+{
+       struct curseg_info *curseg = CURSEG_I(sbi, type);
+       return curseg->segno;
+}
+
+static inline unsigned char curseg_alloc_type(struct f2fs_sb_info *sbi,
+               int type)
+{
+       struct curseg_info *curseg = CURSEG_I(sbi, type);
+       return curseg->alloc_type;
+}
+
+static inline unsigned short curseg_blkoff(struct f2fs_sb_info *sbi, int type)
+{
+       struct curseg_info *curseg = CURSEG_I(sbi, type);
+       return curseg->next_blkoff;
+}
+
+#ifdef CONFIG_F2FS_CHECK_FS
+static inline void check_seg_range(struct f2fs_sb_info *sbi, unsigned int segno)
+{
+       BUG_ON(segno > TOTAL_SEGS(sbi) - 1);
+}
+
+static inline void verify_block_addr(struct f2fs_sb_info *sbi, block_t blk_addr)
+{
+       BUG_ON(blk_addr < SEG0_BLKADDR(sbi));
+       BUG_ON(blk_addr >= MAX_BLKADDR(sbi));
+}
+
+/*
+ * Summary block is always treated as an invalid block
+ */
+static inline void check_block_count(struct f2fs_sb_info *sbi,
+               int segno, struct f2fs_sit_entry *raw_sit)
+{
+       bool is_valid  = test_bit_le(0, raw_sit->valid_map) ? true : false;
+       int valid_blocks = 0;
+       int cur_pos = 0, next_pos;
+
+       /* check segment usage */
+       BUG_ON(GET_SIT_VBLOCKS(raw_sit) > sbi->blocks_per_seg);
+
+       /* check boundary of a given segment number */
+       BUG_ON(segno > TOTAL_SEGS(sbi) - 1);
+
+       /* check bitmap with valid block count */
+       do {
+               if (is_valid) {
+                       next_pos = find_next_zero_bit_le(&raw_sit->valid_map,
+                                       sbi->blocks_per_seg,
+                                       cur_pos);
+                       valid_blocks += next_pos - cur_pos;
+               } else
+                       next_pos = find_next_bit_le(&raw_sit->valid_map,
+                                       sbi->blocks_per_seg,
+                                       cur_pos);
+               cur_pos = next_pos;
+               is_valid = !is_valid;
+       } while (cur_pos < sbi->blocks_per_seg);
+       BUG_ON(GET_SIT_VBLOCKS(raw_sit) != valid_blocks);
+}
+#else
+static inline void check_seg_range(struct f2fs_sb_info *sbi, unsigned int segno)
+{
+       if (segno > TOTAL_SEGS(sbi) - 1)
+               set_sbi_flag(sbi, SBI_NEED_FSCK);
+}
+
+static inline void verify_block_addr(struct f2fs_sb_info *sbi, block_t blk_addr)
+{
+       if (blk_addr < SEG0_BLKADDR(sbi) || blk_addr >= MAX_BLKADDR(sbi))
+               set_sbi_flag(sbi, SBI_NEED_FSCK);
+}
+
+/*
+ * Summary block is always treated as an invalid block
+ */
+static inline void check_block_count(struct f2fs_sb_info *sbi,
+               int segno, struct f2fs_sit_entry *raw_sit)
+{
+       /* check segment usage */
+       if (GET_SIT_VBLOCKS(raw_sit) > sbi->blocks_per_seg)
+               set_sbi_flag(sbi, SBI_NEED_FSCK);
+
+       /* check boundary of a given segment number */
+       if (segno > TOTAL_SEGS(sbi) - 1)
+               set_sbi_flag(sbi, SBI_NEED_FSCK);
+}
+#endif
+
+static inline pgoff_t current_sit_addr(struct f2fs_sb_info *sbi,
+                                               unsigned int start)
+{
+       struct sit_info *sit_i = SIT_I(sbi);
+       unsigned int offset = SIT_BLOCK_OFFSET(start);
+       block_t blk_addr = sit_i->sit_base_addr + offset;
+
+       check_seg_range(sbi, start);
+
+       /* calculate sit block address */
+       if (f2fs_test_bit(offset, sit_i->sit_bitmap))
+               blk_addr += sit_i->sit_blocks;
+
+       return blk_addr;
+}
+
+static inline pgoff_t next_sit_addr(struct f2fs_sb_info *sbi,
+                                               pgoff_t block_addr)
+{
+       struct sit_info *sit_i = SIT_I(sbi);
+       block_addr -= sit_i->sit_base_addr;
+       if (block_addr < sit_i->sit_blocks)
+               block_addr += sit_i->sit_blocks;
+       else
+               block_addr -= sit_i->sit_blocks;
+
+       return block_addr + sit_i->sit_base_addr;
+}
+
+static inline void set_to_next_sit(struct sit_info *sit_i, unsigned int start)
+{
+       unsigned int block_off = SIT_BLOCK_OFFSET(start);
+
+       f2fs_change_bit(block_off, sit_i->sit_bitmap);
+}
+
+static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi)
+{
+       struct sit_info *sit_i = SIT_I(sbi);
+       return sit_i->elapsed_time + CURRENT_TIME_SEC.tv_sec -
+                                               sit_i->mounted_time;
+}
+
+static inline void set_summary(struct f2fs_summary *sum, nid_t nid,
+                       unsigned int ofs_in_node, unsigned char version)
+{
+       sum->nid = cpu_to_le32(nid);
+       sum->ofs_in_node = cpu_to_le16(ofs_in_node);
+       sum->version = version;
+}
+
+static inline block_t start_sum_block(struct f2fs_sb_info *sbi)
+{
+       return __start_cp_addr(sbi) +
+               le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_start_sum);
+}
+
+static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
+{
+       return __start_cp_addr(sbi) +
+               le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_total_block_count)
+                               - (base + 1) + type;
+}
+
+static inline bool sec_usage_check(struct f2fs_sb_info *sbi, unsigned int secno)
+{
+       if (IS_CURSEC(sbi, secno) || (sbi->cur_victim_sec == secno))
+               return true;
+       return false;
+}
+
+static inline unsigned int max_hw_blocks(struct f2fs_sb_info *sbi)
+{
+       struct block_device *bdev = sbi->sb->s_bdev;
+       struct request_queue *q = bdev_get_queue(bdev);
+       return SECTOR_TO_BLOCK(queue_max_sectors(q));
+}
+
+/*
+ * It is very important to gather dirty pages and write at once, so that we can
+ * submit a big bio without interfering other data writes.
+ * By default, 512 pages for directory data,
+ * 512 pages (2MB) * 3 for three types of nodes, and
+ * max_bio_blocks for meta are set.
+ */
+static inline int nr_pages_to_skip(struct f2fs_sb_info *sbi, int type)
+{
+       if (sbi->sb->s_bdi->dirty_exceeded)
+               return 0;
+
+       if (type == DATA)
+               return sbi->blocks_per_seg;
+       else if (type == NODE)
+               return 3 * sbi->blocks_per_seg;
+       else if (type == META)
+               return MAX_BIO_BLOCKS(sbi);
+       else
+               return 0;
+}
+
+/*
+ * When writing pages, it'd better align nr_to_write for segment size.
+ */
+static inline long nr_pages_to_write(struct f2fs_sb_info *sbi, int type,
+                                       struct writeback_control *wbc)
+{
+       long nr_to_write, desired;
+
+       if (wbc->sync_mode != WB_SYNC_NONE)
+               return 0;
+
+       nr_to_write = wbc->nr_to_write;
+
+       if (type == DATA)
+               desired = 4096;
+       else if (type == NODE)
+               desired = 3 * max_hw_blocks(sbi);
+       else
+               desired = MAX_BIO_BLOCKS(sbi);
+
+       wbc->nr_to_write = desired;
+       return desired - nr_to_write;
+}