1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * fs/f2fs/segment.h
4   *
5   * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6   *             http://www.samsung.com/
7   */
8  #include <linux/blkdev.h>
9  #include <linux/backing-dev.h>
10  
11  /* constant macro */
12  #define NULL_SEGNO			((unsigned int)(~0))
13  #define NULL_SECNO			((unsigned int)(~0))
14  
15  #define DEF_RECLAIM_PREFREE_SEGMENTS	5	/* 5% over total segments */
16  #define DEF_MAX_RECLAIM_PREFREE_SEGMENTS	4096	/* 8GB in maximum */
17  
18  #define F2FS_MIN_SEGMENTS	9 /* SB + 2 (CP + SIT + NAT) + SSA + MAIN */
19  #define F2FS_MIN_META_SEGMENTS	8 /* SB + 2 (CP + SIT + NAT) + SSA */
20  
21  /* L: Logical segment # in volume, R: Relative segment # in main area */
22  #define GET_L2R_SEGNO(free_i, segno)	((segno) - (free_i)->start_segno)
23  #define GET_R2L_SEGNO(free_i, segno)	((segno) + (free_i)->start_segno)
24  
25  #define IS_DATASEG(t)	((t) <= CURSEG_COLD_DATA)
26  #define IS_NODESEG(t)	((t) >= CURSEG_HOT_NODE && (t) <= CURSEG_COLD_NODE)
27  #define SE_PAGETYPE(se)	((IS_NODESEG((se)->type) ? NODE : DATA))
28  
sanity_check_seg_type(struct f2fs_sb_info * sbi,unsigned short seg_type)29  static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi,
30  						unsigned short seg_type)
31  {
32  	f2fs_bug_on(sbi, seg_type >= NR_PERSISTENT_LOG);
33  }
34  
35  #define IS_HOT(t)	((t) == CURSEG_HOT_NODE || (t) == CURSEG_HOT_DATA)
36  #define IS_WARM(t)	((t) == CURSEG_WARM_NODE || (t) == CURSEG_WARM_DATA)
37  #define IS_COLD(t)	((t) == CURSEG_COLD_NODE || (t) == CURSEG_COLD_DATA)
38  
39  #define IS_CURSEG(sbi, seg)						\
40  	(((seg) == CURSEG_I(sbi, CURSEG_HOT_DATA)->segno) ||	\
41  	 ((seg) == CURSEG_I(sbi, CURSEG_WARM_DATA)->segno) ||	\
42  	 ((seg) == CURSEG_I(sbi, CURSEG_COLD_DATA)->segno) ||	\
43  	 ((seg) == CURSEG_I(sbi, CURSEG_HOT_NODE)->segno) ||	\
44  	 ((seg) == CURSEG_I(sbi, CURSEG_WARM_NODE)->segno) ||	\
45  	 ((seg) == CURSEG_I(sbi, CURSEG_COLD_NODE)->segno) ||	\
46  	 ((seg) == CURSEG_I(sbi, CURSEG_COLD_DATA_PINNED)->segno) ||	\
47  	 ((seg) == CURSEG_I(sbi, CURSEG_ALL_DATA_ATGC)->segno))
48  
49  #define IS_CURSEC(sbi, secno)						\
50  	(((secno) == CURSEG_I(sbi, CURSEG_HOT_DATA)->segno /		\
51  	  SEGS_PER_SEC(sbi)) ||	\
52  	 ((secno) == CURSEG_I(sbi, CURSEG_WARM_DATA)->segno /		\
53  	  SEGS_PER_SEC(sbi)) ||	\
54  	 ((secno) == CURSEG_I(sbi, CURSEG_COLD_DATA)->segno /		\
55  	  SEGS_PER_SEC(sbi)) ||	\
56  	 ((secno) == CURSEG_I(sbi, CURSEG_HOT_NODE)->segno /		\
57  	  SEGS_PER_SEC(sbi)) ||	\
58  	 ((secno) == CURSEG_I(sbi, CURSEG_WARM_NODE)->segno /		\
59  	  SEGS_PER_SEC(sbi)) ||	\
60  	 ((secno) == CURSEG_I(sbi, CURSEG_COLD_NODE)->segno /		\
61  	  SEGS_PER_SEC(sbi)) ||	\
62  	 ((secno) == CURSEG_I(sbi, CURSEG_COLD_DATA_PINNED)->segno /	\
63  	  SEGS_PER_SEC(sbi)) ||	\
64  	 ((secno) == CURSEG_I(sbi, CURSEG_ALL_DATA_ATGC)->segno /	\
65  	  SEGS_PER_SEC(sbi)))
66  
67  #define MAIN_BLKADDR(sbi)						\
68  	(SM_I(sbi) ? SM_I(sbi)->main_blkaddr : 				\
69  		le32_to_cpu(F2FS_RAW_SUPER(sbi)->main_blkaddr))
70  #define SEG0_BLKADDR(sbi)						\
71  	(SM_I(sbi) ? SM_I(sbi)->seg0_blkaddr : 				\
72  		le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment0_blkaddr))
73  
74  #define MAIN_SEGS(sbi)	(SM_I(sbi)->main_segments)
75  #define MAIN_SECS(sbi)	((sbi)->total_sections)
76  
77  #define TOTAL_SEGS(sbi)							\
78  	(SM_I(sbi) ? SM_I(sbi)->segment_count : 				\
79  		le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment_count))
80  #define TOTAL_BLKS(sbi)	(SEGS_TO_BLKS(sbi, TOTAL_SEGS(sbi)))
81  
82  #define MAX_BLKADDR(sbi)	(SEG0_BLKADDR(sbi) + TOTAL_BLKS(sbi))
83  #define SEGMENT_SIZE(sbi)	(1ULL << ((sbi)->log_blocksize +	\
84  					(sbi)->log_blocks_per_seg))
85  
86  #define START_BLOCK(sbi, segno)	(SEG0_BLKADDR(sbi) +			\
87  	 (SEGS_TO_BLKS(sbi, GET_R2L_SEGNO(FREE_I(sbi), segno))))
88  
89  #define NEXT_FREE_BLKADDR(sbi, curseg)					\
90  	(START_BLOCK(sbi, (curseg)->segno) + (curseg)->next_blkoff)
91  
92  #define GET_SEGOFF_FROM_SEG0(sbi, blk_addr)	((blk_addr) - SEG0_BLKADDR(sbi))
93  #define GET_SEGNO_FROM_SEG0(sbi, blk_addr)				\
94  	(BLKS_TO_SEGS(sbi, GET_SEGOFF_FROM_SEG0(sbi, blk_addr)))
95  #define GET_BLKOFF_FROM_SEG0(sbi, blk_addr)				\
96  	(GET_SEGOFF_FROM_SEG0(sbi, blk_addr) & (BLKS_PER_SEG(sbi) - 1))
97  
98  #define GET_SEGNO(sbi, blk_addr)					\
99  	((!__is_valid_data_blkaddr(blk_addr)) ?			\
100  	NULL_SEGNO : GET_L2R_SEGNO(FREE_I(sbi),			\
101  		GET_SEGNO_FROM_SEG0(sbi, blk_addr)))
102  #define CAP_BLKS_PER_SEC(sbi)					\
103  	(BLKS_PER_SEC(sbi) - (sbi)->unusable_blocks_per_sec)
104  #define CAP_SEGS_PER_SEC(sbi)					\
105  	(SEGS_PER_SEC(sbi) -					\
106  	BLKS_TO_SEGS(sbi, (sbi)->unusable_blocks_per_sec))
107  #define GET_SEC_FROM_SEG(sbi, segno)				\
108  	(((segno) == -1) ? -1 : (segno) / SEGS_PER_SEC(sbi))
109  #define GET_SEG_FROM_SEC(sbi, secno)				\
110  	((secno) * SEGS_PER_SEC(sbi))
111  #define GET_ZONE_FROM_SEC(sbi, secno)				\
112  	(((secno) == -1) ? -1 : (secno) / (sbi)->secs_per_zone)
113  #define GET_ZONE_FROM_SEG(sbi, segno)				\
114  	GET_ZONE_FROM_SEC(sbi, GET_SEC_FROM_SEG(sbi, segno))
115  
116  #define GET_SUM_BLOCK(sbi, segno)				\
117  	((sbi)->sm_info->ssa_blkaddr + (segno))
118  
119  #define GET_SUM_TYPE(footer) ((footer)->entry_type)
120  #define SET_SUM_TYPE(footer, type) ((footer)->entry_type = (type))
121  
122  #define SIT_ENTRY_OFFSET(sit_i, segno)					\
123  	((segno) % (sit_i)->sents_per_block)
124  #define SIT_BLOCK_OFFSET(segno)					\
125  	((segno) / SIT_ENTRY_PER_BLOCK)
126  #define	START_SEGNO(segno)		\
127  	(SIT_BLOCK_OFFSET(segno) * SIT_ENTRY_PER_BLOCK)
128  #define SIT_BLK_CNT(sbi)			\
129  	DIV_ROUND_UP(MAIN_SEGS(sbi), SIT_ENTRY_PER_BLOCK)
130  #define f2fs_bitmap_size(nr)			\
131  	(BITS_TO_LONGS(nr) * sizeof(unsigned long))
132  
133  #define SECTOR_FROM_BLOCK(blk_addr)					\
134  	(((sector_t)blk_addr) << F2FS_LOG_SECTORS_PER_BLOCK)
135  #define SECTOR_TO_BLOCK(sectors)					\
136  	((sectors) >> F2FS_LOG_SECTORS_PER_BLOCK)
137  
138  /*
139   * In the victim_sel_policy->alloc_mode, there are three block allocation modes.
140   * LFS writes data sequentially with cleaning operations.
141   * SSR (Slack Space Recycle) reuses obsolete space without cleaning operations.
142   * AT_SSR (Age Threshold based Slack Space Recycle) merges fragments into
143   * fragmented segment which has similar aging degree.
144   */
145  enum {
146  	LFS = 0,
147  	SSR,
148  	AT_SSR,
149  };
150  
151  /*
152   * In the victim_sel_policy->gc_mode, there are three gc, aka cleaning, modes.
153   * GC_CB is based on cost-benefit algorithm.
154   * GC_GREEDY is based on greedy algorithm.
155   * GC_AT is based on age-threshold algorithm.
156   */
157  enum {
158  	GC_CB = 0,
159  	GC_GREEDY,
160  	GC_AT,
161  	ALLOC_NEXT,
162  	FLUSH_DEVICE,
163  	MAX_GC_POLICY,
164  };
165  
166  /*
167   * BG_GC means the background cleaning job.
168   * FG_GC means the on-demand cleaning job.
169   */
170  enum {
171  	BG_GC = 0,
172  	FG_GC,
173  };
174  
175  /* for a function parameter to select a victim segment */
176  struct victim_sel_policy {
177  	int alloc_mode;			/* LFS or SSR */
178  	int gc_mode;			/* GC_CB or GC_GREEDY */
179  	unsigned long *dirty_bitmap;	/* dirty segment/section bitmap */
180  	unsigned int max_search;	/*
181  					 * maximum # of segments/sections
182  					 * to search
183  					 */
184  	unsigned int offset;		/* last scanned bitmap offset */
185  	unsigned int ofs_unit;		/* bitmap search unit */
186  	unsigned int min_cost;		/* minimum cost */
187  	unsigned long long oldest_age;	/* oldest age of segments having the same min cost */
188  	unsigned int min_segno;		/* segment # having min. cost */
189  	unsigned long long age;		/* mtime of GCed section*/
190  	unsigned long long age_threshold;/* age threshold */
191  	bool one_time_gc;		/* one time GC */
192  };
193  
194  struct seg_entry {
195  	unsigned int type:6;		/* segment type like CURSEG_XXX_TYPE */
196  	unsigned int valid_blocks:10;	/* # of valid blocks */
197  	unsigned int ckpt_valid_blocks:10;	/* # of valid blocks last cp */
198  	unsigned int padding:6;		/* padding */
199  	unsigned char *cur_valid_map;	/* validity bitmap of blocks */
200  #ifdef CONFIG_F2FS_CHECK_FS
201  	unsigned char *cur_valid_map_mir;	/* mirror of current valid bitmap */
202  #endif
203  	/*
204  	 * # of valid blocks and the validity bitmap stored in the last
205  	 * checkpoint pack. This information is used by the SSR mode.
206  	 */
207  	unsigned char *ckpt_valid_map;	/* validity bitmap of blocks last cp */
208  	unsigned char *discard_map;
209  	unsigned long long mtime;	/* modification time of the segment */
210  };
211  
212  struct sec_entry {
213  	unsigned int valid_blocks;	/* # of valid blocks in a section */
214  };
215  
216  #define MAX_SKIP_GC_COUNT			16
217  
218  struct revoke_entry {
219  	struct list_head list;
220  	block_t old_addr;		/* for revoking when fail to commit */
221  	pgoff_t index;
222  };
223  
224  struct sit_info {
225  	block_t sit_base_addr;		/* start block address of SIT area */
226  	block_t sit_blocks;		/* # of blocks used by SIT area */
227  	block_t written_valid_blocks;	/* # of valid blocks in main area */
228  	char *bitmap;			/* all bitmaps pointer */
229  	char *sit_bitmap;		/* SIT bitmap pointer */
230  #ifdef CONFIG_F2FS_CHECK_FS
231  	char *sit_bitmap_mir;		/* SIT bitmap mirror */
232  
233  	/* bitmap of segments to be ignored by GC in case of errors */
234  	unsigned long *invalid_segmap;
235  #endif
236  	unsigned int bitmap_size;	/* SIT bitmap size */
237  
238  	unsigned long *tmp_map;			/* bitmap for temporal use */
239  	unsigned long *dirty_sentries_bitmap;	/* bitmap for dirty sentries */
240  	unsigned int dirty_sentries;		/* # of dirty sentries */
241  	unsigned int sents_per_block;		/* # of SIT entries per block */
242  	struct rw_semaphore sentry_lock;	/* to protect SIT cache */
243  	struct seg_entry *sentries;		/* SIT segment-level cache */
244  	struct sec_entry *sec_entries;		/* SIT section-level cache */
245  
246  	/* for cost-benefit algorithm in cleaning procedure */
247  	unsigned long long elapsed_time;	/* elapsed time after mount */
248  	unsigned long long mounted_time;	/* mount time */
249  	unsigned long long min_mtime;		/* min. modification time */
250  	unsigned long long max_mtime;		/* max. modification time */
251  	unsigned long long dirty_min_mtime;	/* rerange candidates in GC_AT */
252  	unsigned long long dirty_max_mtime;	/* rerange candidates in GC_AT */
253  
254  	unsigned int last_victim[MAX_GC_POLICY]; /* last victim segment # */
255  };
256  
257  struct free_segmap_info {
258  	unsigned int start_segno;	/* start segment number logically */
259  	unsigned int free_segments;	/* # of free segments */
260  	unsigned int free_sections;	/* # of free sections */
261  	spinlock_t segmap_lock;		/* free segmap lock */
262  	unsigned long *free_segmap;	/* free segment bitmap */
263  	unsigned long *free_secmap;	/* free section bitmap */
264  };
265  
266  /* Notice: The order of dirty type is same with CURSEG_XXX in f2fs.h */
267  enum dirty_type {
268  	DIRTY_HOT_DATA,		/* dirty segments assigned as hot data logs */
269  	DIRTY_WARM_DATA,	/* dirty segments assigned as warm data logs */
270  	DIRTY_COLD_DATA,	/* dirty segments assigned as cold data logs */
271  	DIRTY_HOT_NODE,		/* dirty segments assigned as hot node logs */
272  	DIRTY_WARM_NODE,	/* dirty segments assigned as warm node logs */
273  	DIRTY_COLD_NODE,	/* dirty segments assigned as cold node logs */
274  	DIRTY,			/* to count # of dirty segments */
275  	PRE,			/* to count # of entirely obsolete segments */
276  	NR_DIRTY_TYPE
277  };
278  
279  struct dirty_seglist_info {
280  	unsigned long *dirty_segmap[NR_DIRTY_TYPE];
281  	unsigned long *dirty_secmap;
282  	struct mutex seglist_lock;		/* lock for segment bitmaps */
283  	int nr_dirty[NR_DIRTY_TYPE];		/* # of dirty segments */
284  	unsigned long *victim_secmap;		/* background GC victims */
285  	unsigned long *pinned_secmap;		/* pinned victims from foreground GC */
286  	unsigned int pinned_secmap_cnt;		/* count of victims which has pinned data */
287  	bool enable_pin_section;		/* enable pinning section */
288  };
289  
290  /* for active log information */
291  struct curseg_info {
292  	struct mutex curseg_mutex;		/* lock for consistency */
293  	struct f2fs_summary_block *sum_blk;	/* cached summary block */
294  	struct rw_semaphore journal_rwsem;	/* protect journal area */
295  	struct f2fs_journal *journal;		/* cached journal info */
296  	unsigned char alloc_type;		/* current allocation type */
297  	unsigned short seg_type;		/* segment type like CURSEG_XXX_TYPE */
298  	unsigned int segno;			/* current segment number */
299  	unsigned short next_blkoff;		/* next block offset to write */
300  	unsigned int zone;			/* current zone number */
301  	unsigned int next_segno;		/* preallocated segment */
302  	int fragment_remained_chunk;		/* remained block size in a chunk for block fragmentation mode */
303  	bool inited;				/* indicate inmem log is inited */
304  };
305  
306  struct sit_entry_set {
307  	struct list_head set_list;	/* link with all sit sets */
308  	unsigned int start_segno;	/* start segno of sits in set */
309  	unsigned int entry_cnt;		/* the # of sit entries in set */
310  };
311  
312  /*
313   * inline functions
314   */
CURSEG_I(struct f2fs_sb_info * sbi,int type)315  static inline struct curseg_info *CURSEG_I(struct f2fs_sb_info *sbi, int type)
316  {
317  	return (struct curseg_info *)(SM_I(sbi)->curseg_array + type);
318  }
319  
get_seg_entry(struct f2fs_sb_info * sbi,unsigned int segno)320  static inline struct seg_entry *get_seg_entry(struct f2fs_sb_info *sbi,
321  						unsigned int segno)
322  {
323  	struct sit_info *sit_i = SIT_I(sbi);
324  	return &sit_i->sentries[segno];
325  }
326  
get_sec_entry(struct f2fs_sb_info * sbi,unsigned int segno)327  static inline struct sec_entry *get_sec_entry(struct f2fs_sb_info *sbi,
328  						unsigned int segno)
329  {
330  	struct sit_info *sit_i = SIT_I(sbi);
331  	return &sit_i->sec_entries[GET_SEC_FROM_SEG(sbi, segno)];
332  }
333  
get_valid_blocks(struct f2fs_sb_info * sbi,unsigned int segno,bool use_section)334  static inline unsigned int get_valid_blocks(struct f2fs_sb_info *sbi,
335  				unsigned int segno, bool use_section)
336  {
337  	/*
338  	 * In order to get # of valid blocks in a section instantly from many
339  	 * segments, f2fs manages two counting structures separately.
340  	 */
341  	if (use_section && __is_large_section(sbi))
342  		return get_sec_entry(sbi, segno)->valid_blocks;
343  	else
344  		return get_seg_entry(sbi, segno)->valid_blocks;
345  }
346  
get_ckpt_valid_blocks(struct f2fs_sb_info * sbi,unsigned int segno,bool use_section)347  static inline unsigned int get_ckpt_valid_blocks(struct f2fs_sb_info *sbi,
348  				unsigned int segno, bool use_section)
349  {
350  	if (use_section && __is_large_section(sbi)) {
351  		unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
352  		unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
353  		unsigned int blocks = 0;
354  		int i;
355  
356  		for (i = 0; i < SEGS_PER_SEC(sbi); i++, start_segno++) {
357  			struct seg_entry *se = get_seg_entry(sbi, start_segno);
358  
359  			blocks += se->ckpt_valid_blocks;
360  		}
361  		return blocks;
362  	}
363  	return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
364  }
365  
seg_info_from_raw_sit(struct seg_entry * se,struct f2fs_sit_entry * rs)366  static inline void seg_info_from_raw_sit(struct seg_entry *se,
367  					struct f2fs_sit_entry *rs)
368  {
369  	se->valid_blocks = GET_SIT_VBLOCKS(rs);
370  	se->ckpt_valid_blocks = GET_SIT_VBLOCKS(rs);
371  	memcpy(se->cur_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
372  	memcpy(se->ckpt_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
373  #ifdef CONFIG_F2FS_CHECK_FS
374  	memcpy(se->cur_valid_map_mir, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
375  #endif
376  	se->type = GET_SIT_TYPE(rs);
377  	se->mtime = le64_to_cpu(rs->mtime);
378  }
379  
__seg_info_to_raw_sit(struct seg_entry * se,struct f2fs_sit_entry * rs)380  static inline void __seg_info_to_raw_sit(struct seg_entry *se,
381  					struct f2fs_sit_entry *rs)
382  {
383  	unsigned short raw_vblocks = (se->type << SIT_VBLOCKS_SHIFT) |
384  					se->valid_blocks;
385  	rs->vblocks = cpu_to_le16(raw_vblocks);
386  	memcpy(rs->valid_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
387  	rs->mtime = cpu_to_le64(se->mtime);
388  }
389  
seg_info_to_sit_page(struct f2fs_sb_info * sbi,struct page * page,unsigned int start)390  static inline void seg_info_to_sit_page(struct f2fs_sb_info *sbi,
391  				struct page *page, unsigned int start)
392  {
393  	struct f2fs_sit_block *raw_sit;
394  	struct seg_entry *se;
395  	struct f2fs_sit_entry *rs;
396  	unsigned int end = min(start + SIT_ENTRY_PER_BLOCK,
397  					(unsigned long)MAIN_SEGS(sbi));
398  	int i;
399  
400  	raw_sit = (struct f2fs_sit_block *)page_address(page);
401  	memset(raw_sit, 0, PAGE_SIZE);
402  	for (i = 0; i < end - start; i++) {
403  		rs = &raw_sit->entries[i];
404  		se = get_seg_entry(sbi, start + i);
405  		__seg_info_to_raw_sit(se, rs);
406  	}
407  }
408  
seg_info_to_raw_sit(struct seg_entry * se,struct f2fs_sit_entry * rs)409  static inline void seg_info_to_raw_sit(struct seg_entry *se,
410  					struct f2fs_sit_entry *rs)
411  {
412  	__seg_info_to_raw_sit(se, rs);
413  
414  	memcpy(se->ckpt_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
415  	se->ckpt_valid_blocks = se->valid_blocks;
416  }
417  
find_next_inuse(struct free_segmap_info * free_i,unsigned int max,unsigned int segno)418  static inline unsigned int find_next_inuse(struct free_segmap_info *free_i,
419  		unsigned int max, unsigned int segno)
420  {
421  	unsigned int ret;
422  	spin_lock(&free_i->segmap_lock);
423  	ret = find_next_bit(free_i->free_segmap, max, segno);
424  	spin_unlock(&free_i->segmap_lock);
425  	return ret;
426  }
427  
__set_free(struct f2fs_sb_info * sbi,unsigned int segno)428  static inline void __set_free(struct f2fs_sb_info *sbi, unsigned int segno)
429  {
430  	struct free_segmap_info *free_i = FREE_I(sbi);
431  	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
432  	unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
433  	unsigned int next;
434  	unsigned int usable_segs = f2fs_usable_segs_in_sec(sbi);
435  
436  	spin_lock(&free_i->segmap_lock);
437  	clear_bit(segno, free_i->free_segmap);
438  	free_i->free_segments++;
439  
440  	next = find_next_bit(free_i->free_segmap,
441  			start_segno + SEGS_PER_SEC(sbi), start_segno);
442  	if (next >= start_segno + usable_segs) {
443  		clear_bit(secno, free_i->free_secmap);
444  		free_i->free_sections++;
445  	}
446  	spin_unlock(&free_i->segmap_lock);
447  }
448  
__set_inuse(struct f2fs_sb_info * sbi,unsigned int segno)449  static inline void __set_inuse(struct f2fs_sb_info *sbi,
450  		unsigned int segno)
451  {
452  	struct free_segmap_info *free_i = FREE_I(sbi);
453  	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
454  
455  	set_bit(segno, free_i->free_segmap);
456  	free_i->free_segments--;
457  	if (!test_and_set_bit(secno, free_i->free_secmap))
458  		free_i->free_sections--;
459  }
460  
__set_test_and_free(struct f2fs_sb_info * sbi,unsigned int segno,bool inmem)461  static inline void __set_test_and_free(struct f2fs_sb_info *sbi,
462  		unsigned int segno, bool inmem)
463  {
464  	struct free_segmap_info *free_i = FREE_I(sbi);
465  	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
466  	unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
467  	unsigned int next;
468  	unsigned int usable_segs = f2fs_usable_segs_in_sec(sbi);
469  
470  	spin_lock(&free_i->segmap_lock);
471  	if (test_and_clear_bit(segno, free_i->free_segmap)) {
472  		free_i->free_segments++;
473  
474  		if (!inmem && IS_CURSEC(sbi, secno))
475  			goto skip_free;
476  		next = find_next_bit(free_i->free_segmap,
477  				start_segno + SEGS_PER_SEC(sbi), start_segno);
478  		if (next >= start_segno + usable_segs) {
479  			if (test_and_clear_bit(secno, free_i->free_secmap))
480  				free_i->free_sections++;
481  		}
482  	}
483  skip_free:
484  	spin_unlock(&free_i->segmap_lock);
485  }
486  
__set_test_and_inuse(struct f2fs_sb_info * sbi,unsigned int segno)487  static inline void __set_test_and_inuse(struct f2fs_sb_info *sbi,
488  		unsigned int segno)
489  {
490  	struct free_segmap_info *free_i = FREE_I(sbi);
491  	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
492  
493  	spin_lock(&free_i->segmap_lock);
494  	if (!test_and_set_bit(segno, free_i->free_segmap)) {
495  		free_i->free_segments--;
496  		if (!test_and_set_bit(secno, free_i->free_secmap))
497  			free_i->free_sections--;
498  	}
499  	spin_unlock(&free_i->segmap_lock);
500  }
501  
get_sit_bitmap(struct f2fs_sb_info * sbi,void * dst_addr)502  static inline void get_sit_bitmap(struct f2fs_sb_info *sbi,
503  		void *dst_addr)
504  {
505  	struct sit_info *sit_i = SIT_I(sbi);
506  
507  #ifdef CONFIG_F2FS_CHECK_FS
508  	if (memcmp(sit_i->sit_bitmap, sit_i->sit_bitmap_mir,
509  						sit_i->bitmap_size))
510  		f2fs_bug_on(sbi, 1);
511  #endif
512  	memcpy(dst_addr, sit_i->sit_bitmap, sit_i->bitmap_size);
513  }
514  
written_block_count(struct f2fs_sb_info * sbi)515  static inline block_t written_block_count(struct f2fs_sb_info *sbi)
516  {
517  	return SIT_I(sbi)->written_valid_blocks;
518  }
519  
free_segments(struct f2fs_sb_info * sbi)520  static inline unsigned int free_segments(struct f2fs_sb_info *sbi)
521  {
522  	return FREE_I(sbi)->free_segments;
523  }
524  
reserved_segments(struct f2fs_sb_info * sbi)525  static inline unsigned int reserved_segments(struct f2fs_sb_info *sbi)
526  {
527  	return SM_I(sbi)->reserved_segments +
528  			SM_I(sbi)->additional_reserved_segments;
529  }
530  
free_sections(struct f2fs_sb_info * sbi)531  static inline unsigned int free_sections(struct f2fs_sb_info *sbi)
532  {
533  	return FREE_I(sbi)->free_sections;
534  }
535  
prefree_segments(struct f2fs_sb_info * sbi)536  static inline unsigned int prefree_segments(struct f2fs_sb_info *sbi)
537  {
538  	return DIRTY_I(sbi)->nr_dirty[PRE];
539  }
540  
dirty_segments(struct f2fs_sb_info * sbi)541  static inline unsigned int dirty_segments(struct f2fs_sb_info *sbi)
542  {
543  	return DIRTY_I(sbi)->nr_dirty[DIRTY_HOT_DATA] +
544  		DIRTY_I(sbi)->nr_dirty[DIRTY_WARM_DATA] +
545  		DIRTY_I(sbi)->nr_dirty[DIRTY_COLD_DATA] +
546  		DIRTY_I(sbi)->nr_dirty[DIRTY_HOT_NODE] +
547  		DIRTY_I(sbi)->nr_dirty[DIRTY_WARM_NODE] +
548  		DIRTY_I(sbi)->nr_dirty[DIRTY_COLD_NODE];
549  }
550  
overprovision_segments(struct f2fs_sb_info * sbi)551  static inline int overprovision_segments(struct f2fs_sb_info *sbi)
552  {
553  	return SM_I(sbi)->ovp_segments;
554  }
555  
reserved_sections(struct f2fs_sb_info * sbi)556  static inline int reserved_sections(struct f2fs_sb_info *sbi)
557  {
558  	return GET_SEC_FROM_SEG(sbi, reserved_segments(sbi));
559  }
560  
has_curseg_enough_space(struct f2fs_sb_info * sbi,unsigned int node_blocks,unsigned int dent_blocks)561  static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi,
562  			unsigned int node_blocks, unsigned int dent_blocks)
563  {
564  
565  	unsigned segno, left_blocks;
566  	int i;
567  
568  	/* check current node sections in the worst case. */
569  	for (i = CURSEG_HOT_NODE; i <= CURSEG_COLD_NODE; i++) {
570  		segno = CURSEG_I(sbi, i)->segno;
571  		left_blocks = CAP_BLKS_PER_SEC(sbi) -
572  				get_ckpt_valid_blocks(sbi, segno, true);
573  		if (node_blocks > left_blocks)
574  			return false;
575  	}
576  
577  	/* check current data section for dentry blocks. */
578  	segno = CURSEG_I(sbi, CURSEG_HOT_DATA)->segno;
579  	left_blocks = CAP_BLKS_PER_SEC(sbi) -
580  			get_ckpt_valid_blocks(sbi, segno, true);
581  	if (dent_blocks > left_blocks)
582  		return false;
583  	return true;
584  }
585  
586  /*
587   * calculate needed sections for dirty node/dentry
588   * and call has_curseg_enough_space
589   */
__get_secs_required(struct f2fs_sb_info * sbi,unsigned int * lower_p,unsigned int * upper_p,bool * curseg_p)590  static inline void __get_secs_required(struct f2fs_sb_info *sbi,
591  		unsigned int *lower_p, unsigned int *upper_p, bool *curseg_p)
592  {
593  	unsigned int total_node_blocks = get_pages(sbi, F2FS_DIRTY_NODES) +
594  					get_pages(sbi, F2FS_DIRTY_DENTS) +
595  					get_pages(sbi, F2FS_DIRTY_IMETA);
596  	unsigned int total_dent_blocks = get_pages(sbi, F2FS_DIRTY_DENTS);
597  	unsigned int node_secs = total_node_blocks / CAP_BLKS_PER_SEC(sbi);
598  	unsigned int dent_secs = total_dent_blocks / CAP_BLKS_PER_SEC(sbi);
599  	unsigned int node_blocks = total_node_blocks % CAP_BLKS_PER_SEC(sbi);
600  	unsigned int dent_blocks = total_dent_blocks % CAP_BLKS_PER_SEC(sbi);
601  
602  	if (lower_p)
603  		*lower_p = node_secs + dent_secs;
604  	if (upper_p)
605  		*upper_p = node_secs + dent_secs +
606  			(node_blocks ? 1 : 0) + (dent_blocks ? 1 : 0);
607  	if (curseg_p)
608  		*curseg_p = has_curseg_enough_space(sbi,
609  				node_blocks, dent_blocks);
610  }
611  
has_not_enough_free_secs(struct f2fs_sb_info * sbi,int freed,int needed)612  static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,
613  					int freed, int needed)
614  {
615  	unsigned int free_secs, lower_secs, upper_secs;
616  	bool curseg_space;
617  
618  	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
619  		return false;
620  
621  	__get_secs_required(sbi, &lower_secs, &upper_secs, &curseg_space);
622  
623  	free_secs = free_sections(sbi) + freed;
624  	lower_secs += needed + reserved_sections(sbi);
625  	upper_secs += needed + reserved_sections(sbi);
626  
627  	if (free_secs > upper_secs)
628  		return false;
629  	if (free_secs <= lower_secs)
630  		return true;
631  	return !curseg_space;
632  }
633  
has_enough_free_secs(struct f2fs_sb_info * sbi,int freed,int needed)634  static inline bool has_enough_free_secs(struct f2fs_sb_info *sbi,
635  					int freed, int needed)
636  {
637  	return !has_not_enough_free_secs(sbi, freed, needed);
638  }
639  
f2fs_is_checkpoint_ready(struct f2fs_sb_info * sbi)640  static inline bool f2fs_is_checkpoint_ready(struct f2fs_sb_info *sbi)
641  {
642  	if (likely(!is_sbi_flag_set(sbi, SBI_CP_DISABLED)))
643  		return true;
644  	if (likely(has_enough_free_secs(sbi, 0, 0)))
645  		return true;
646  	return false;
647  }
648  
excess_prefree_segs(struct f2fs_sb_info * sbi)649  static inline bool excess_prefree_segs(struct f2fs_sb_info *sbi)
650  {
651  	return prefree_segments(sbi) > SM_I(sbi)->rec_prefree_segments;
652  }
653  
utilization(struct f2fs_sb_info * sbi)654  static inline int utilization(struct f2fs_sb_info *sbi)
655  {
656  	return div_u64((u64)valid_user_blocks(sbi) * 100,
657  					sbi->user_block_count);
658  }
659  
660  /*
661   * Sometimes f2fs may be better to drop out-of-place update policy.
662   * And, users can control the policy through sysfs entries.
663   * There are five policies with triggering conditions as follows.
664   * F2FS_IPU_FORCE - all the time,
665   * F2FS_IPU_SSR - if SSR mode is activated,
666   * F2FS_IPU_UTIL - if FS utilization is over threashold,
667   * F2FS_IPU_SSR_UTIL - if SSR mode is activated and FS utilization is over
668   *                     threashold,
669   * F2FS_IPU_FSYNC - activated in fsync path only for high performance flash
670   *                     storages. IPU will be triggered only if the # of dirty
671   *                     pages over min_fsync_blocks. (=default option)
672   * F2FS_IPU_ASYNC - do IPU given by asynchronous write requests.
673   * F2FS_IPU_NOCACHE - disable IPU bio cache.
674   * F2FS_IPU_HONOR_OPU_WRITE - use OPU write prior to IPU write if inode has
675   *                            FI_OPU_WRITE flag.
676   * F2FS_IPU_DISABLE - disable IPU. (=default option in LFS mode)
677   */
678  #define DEF_MIN_IPU_UTIL	70
679  #define DEF_MIN_FSYNC_BLOCKS	8
680  #define DEF_MIN_HOT_BLOCKS	16
681  
682  #define SMALL_VOLUME_SEGMENTS	(16 * 512)	/* 16GB */
683  
684  #define F2FS_IPU_DISABLE	0
685  
686  /* Modification on enum should be synchronized with ipu_mode_names array */
687  enum {
688  	F2FS_IPU_FORCE,
689  	F2FS_IPU_SSR,
690  	F2FS_IPU_UTIL,
691  	F2FS_IPU_SSR_UTIL,
692  	F2FS_IPU_FSYNC,
693  	F2FS_IPU_ASYNC,
694  	F2FS_IPU_NOCACHE,
695  	F2FS_IPU_HONOR_OPU_WRITE,
696  	F2FS_IPU_MAX,
697  };
698  
IS_F2FS_IPU_DISABLE(struct f2fs_sb_info * sbi)699  static inline bool IS_F2FS_IPU_DISABLE(struct f2fs_sb_info *sbi)
700  {
701  	return SM_I(sbi)->ipu_policy == F2FS_IPU_DISABLE;
702  }
703  
704  #define F2FS_IPU_POLICY(name)					\
705  static inline bool IS_##name(struct f2fs_sb_info *sbi)		\
706  {								\
707  	return SM_I(sbi)->ipu_policy & BIT(name);		\
708  }
709  
710  F2FS_IPU_POLICY(F2FS_IPU_FORCE);
711  F2FS_IPU_POLICY(F2FS_IPU_SSR);
712  F2FS_IPU_POLICY(F2FS_IPU_UTIL);
713  F2FS_IPU_POLICY(F2FS_IPU_SSR_UTIL);
714  F2FS_IPU_POLICY(F2FS_IPU_FSYNC);
715  F2FS_IPU_POLICY(F2FS_IPU_ASYNC);
716  F2FS_IPU_POLICY(F2FS_IPU_NOCACHE);
717  F2FS_IPU_POLICY(F2FS_IPU_HONOR_OPU_WRITE);
718  
curseg_segno(struct f2fs_sb_info * sbi,int type)719  static inline unsigned int curseg_segno(struct f2fs_sb_info *sbi,
720  		int type)
721  {
722  	struct curseg_info *curseg = CURSEG_I(sbi, type);
723  	return curseg->segno;
724  }
725  
curseg_alloc_type(struct f2fs_sb_info * sbi,int type)726  static inline unsigned char curseg_alloc_type(struct f2fs_sb_info *sbi,
727  		int type)
728  {
729  	struct curseg_info *curseg = CURSEG_I(sbi, type);
730  	return curseg->alloc_type;
731  }
732  
valid_main_segno(struct f2fs_sb_info * sbi,unsigned int segno)733  static inline bool valid_main_segno(struct f2fs_sb_info *sbi,
734  		unsigned int segno)
735  {
736  	return segno <= (MAIN_SEGS(sbi) - 1);
737  }
738  
verify_fio_blkaddr(struct f2fs_io_info * fio)739  static inline void verify_fio_blkaddr(struct f2fs_io_info *fio)
740  {
741  	struct f2fs_sb_info *sbi = fio->sbi;
742  
743  	if (__is_valid_data_blkaddr(fio->old_blkaddr))
744  		verify_blkaddr(sbi, fio->old_blkaddr, __is_meta_io(fio) ?
745  					META_GENERIC : DATA_GENERIC);
746  	verify_blkaddr(sbi, fio->new_blkaddr, __is_meta_io(fio) ?
747  					META_GENERIC : DATA_GENERIC_ENHANCE);
748  }
749  
750  /*
751   * Summary block is always treated as an invalid block
752   */
check_block_count(struct f2fs_sb_info * sbi,int segno,struct f2fs_sit_entry * raw_sit)753  static inline int check_block_count(struct f2fs_sb_info *sbi,
754  		int segno, struct f2fs_sit_entry *raw_sit)
755  {
756  	bool is_valid  = test_bit_le(0, raw_sit->valid_map) ? true : false;
757  	int valid_blocks = 0;
758  	int cur_pos = 0, next_pos;
759  	unsigned int usable_blks_per_seg = f2fs_usable_blks_in_seg(sbi, segno);
760  
761  	/* check bitmap with valid block count */
762  	do {
763  		if (is_valid) {
764  			next_pos = find_next_zero_bit_le(&raw_sit->valid_map,
765  					usable_blks_per_seg,
766  					cur_pos);
767  			valid_blocks += next_pos - cur_pos;
768  		} else
769  			next_pos = find_next_bit_le(&raw_sit->valid_map,
770  					usable_blks_per_seg,
771  					cur_pos);
772  		cur_pos = next_pos;
773  		is_valid = !is_valid;
774  	} while (cur_pos < usable_blks_per_seg);
775  
776  	if (unlikely(GET_SIT_VBLOCKS(raw_sit) != valid_blocks)) {
777  		f2fs_err(sbi, "Mismatch valid blocks %d vs. %d",
778  			 GET_SIT_VBLOCKS(raw_sit), valid_blocks);
779  		set_sbi_flag(sbi, SBI_NEED_FSCK);
780  		f2fs_handle_error(sbi, ERROR_INCONSISTENT_SIT);
781  		return -EFSCORRUPTED;
782  	}
783  
784  	if (usable_blks_per_seg < BLKS_PER_SEG(sbi))
785  		f2fs_bug_on(sbi, find_next_bit_le(&raw_sit->valid_map,
786  				BLKS_PER_SEG(sbi),
787  				usable_blks_per_seg) != BLKS_PER_SEG(sbi));
788  
789  	/* check segment usage, and check boundary of a given segment number */
790  	if (unlikely(GET_SIT_VBLOCKS(raw_sit) > usable_blks_per_seg
791  					|| !valid_main_segno(sbi, segno))) {
792  		f2fs_err(sbi, "Wrong valid blocks %d or segno %u",
793  			 GET_SIT_VBLOCKS(raw_sit), segno);
794  		set_sbi_flag(sbi, SBI_NEED_FSCK);
795  		f2fs_handle_error(sbi, ERROR_INCONSISTENT_SIT);
796  		return -EFSCORRUPTED;
797  	}
798  	return 0;
799  }
800  
current_sit_addr(struct f2fs_sb_info * sbi,unsigned int start)801  static inline pgoff_t current_sit_addr(struct f2fs_sb_info *sbi,
802  						unsigned int start)
803  {
804  	struct sit_info *sit_i = SIT_I(sbi);
805  	unsigned int offset = SIT_BLOCK_OFFSET(start);
806  	block_t blk_addr = sit_i->sit_base_addr + offset;
807  
808  	f2fs_bug_on(sbi, !valid_main_segno(sbi, start));
809  
810  #ifdef CONFIG_F2FS_CHECK_FS
811  	if (f2fs_test_bit(offset, sit_i->sit_bitmap) !=
812  			f2fs_test_bit(offset, sit_i->sit_bitmap_mir))
813  		f2fs_bug_on(sbi, 1);
814  #endif
815  
816  	/* calculate sit block address */
817  	if (f2fs_test_bit(offset, sit_i->sit_bitmap))
818  		blk_addr += sit_i->sit_blocks;
819  
820  	return blk_addr;
821  }
822  
next_sit_addr(struct f2fs_sb_info * sbi,pgoff_t block_addr)823  static inline pgoff_t next_sit_addr(struct f2fs_sb_info *sbi,
824  						pgoff_t block_addr)
825  {
826  	struct sit_info *sit_i = SIT_I(sbi);
827  	block_addr -= sit_i->sit_base_addr;
828  	if (block_addr < sit_i->sit_blocks)
829  		block_addr += sit_i->sit_blocks;
830  	else
831  		block_addr -= sit_i->sit_blocks;
832  
833  	return block_addr + sit_i->sit_base_addr;
834  }
835  
set_to_next_sit(struct sit_info * sit_i,unsigned int start)836  static inline void set_to_next_sit(struct sit_info *sit_i, unsigned int start)
837  {
838  	unsigned int block_off = SIT_BLOCK_OFFSET(start);
839  
840  	f2fs_change_bit(block_off, sit_i->sit_bitmap);
841  #ifdef CONFIG_F2FS_CHECK_FS
842  	f2fs_change_bit(block_off, sit_i->sit_bitmap_mir);
843  #endif
844  }
845  
get_mtime(struct f2fs_sb_info * sbi,bool base_time)846  static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi,
847  						bool base_time)
848  {
849  	struct sit_info *sit_i = SIT_I(sbi);
850  	time64_t diff, now = ktime_get_boottime_seconds();
851  
852  	if (now >= sit_i->mounted_time)
853  		return sit_i->elapsed_time + now - sit_i->mounted_time;
854  
855  	/* system time is set to the past */
856  	if (!base_time) {
857  		diff = sit_i->mounted_time - now;
858  		if (sit_i->elapsed_time >= diff)
859  			return sit_i->elapsed_time - diff;
860  		return 0;
861  	}
862  	return sit_i->elapsed_time;
863  }
864  
set_summary(struct f2fs_summary * sum,nid_t nid,unsigned int ofs_in_node,unsigned char version)865  static inline void set_summary(struct f2fs_summary *sum, nid_t nid,
866  			unsigned int ofs_in_node, unsigned char version)
867  {
868  	sum->nid = cpu_to_le32(nid);
869  	sum->ofs_in_node = cpu_to_le16(ofs_in_node);
870  	sum->version = version;
871  }
872  
start_sum_block(struct f2fs_sb_info * sbi)873  static inline block_t start_sum_block(struct f2fs_sb_info *sbi)
874  {
875  	return __start_cp_addr(sbi) +
876  		le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_start_sum);
877  }
878  
sum_blk_addr(struct f2fs_sb_info * sbi,int base,int type)879  static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
880  {
881  	return __start_cp_addr(sbi) +
882  		le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_total_block_count)
883  				- (base + 1) + type;
884  }
885  
sec_usage_check(struct f2fs_sb_info * sbi,unsigned int secno)886  static inline bool sec_usage_check(struct f2fs_sb_info *sbi, unsigned int secno)
887  {
888  	if (IS_CURSEC(sbi, secno) || (sbi->cur_victim_sec == secno))
889  		return true;
890  	return false;
891  }
892  
893  /*
894   * It is very important to gather dirty pages and write at once, so that we can
895   * submit a big bio without interfering other data writes.
896   * By default, 512 pages for directory data,
897   * 512 pages (2MB) * 8 for nodes, and
898   * 256 pages * 8 for meta are set.
899   */
nr_pages_to_skip(struct f2fs_sb_info * sbi,int type)900  static inline int nr_pages_to_skip(struct f2fs_sb_info *sbi, int type)
901  {
902  	if (sbi->sb->s_bdi->wb.dirty_exceeded)
903  		return 0;
904  
905  	if (type == DATA)
906  		return BLKS_PER_SEG(sbi);
907  	else if (type == NODE)
908  		return SEGS_TO_BLKS(sbi, 8);
909  	else if (type == META)
910  		return 8 * BIO_MAX_VECS;
911  	else
912  		return 0;
913  }
914  
915  /*
916   * When writing pages, it'd better align nr_to_write for segment size.
917   */
nr_pages_to_write(struct f2fs_sb_info * sbi,int type,struct writeback_control * wbc)918  static inline long nr_pages_to_write(struct f2fs_sb_info *sbi, int type,
919  					struct writeback_control *wbc)
920  {
921  	long nr_to_write, desired;
922  
923  	if (wbc->sync_mode != WB_SYNC_NONE)
924  		return 0;
925  
926  	nr_to_write = wbc->nr_to_write;
927  	desired = BIO_MAX_VECS;
928  	if (type == NODE)
929  		desired <<= 1;
930  
931  	wbc->nr_to_write = desired;
932  	return desired - nr_to_write;
933  }
934  
wake_up_discard_thread(struct f2fs_sb_info * sbi,bool force)935  static inline void wake_up_discard_thread(struct f2fs_sb_info *sbi, bool force)
936  {
937  	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
938  	bool wakeup = false;
939  	int i;
940  
941  	if (force)
942  		goto wake_up;
943  
944  	mutex_lock(&dcc->cmd_lock);
945  	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
946  		if (i + 1 < dcc->discard_granularity)
947  			break;
948  		if (!list_empty(&dcc->pend_list[i])) {
949  			wakeup = true;
950  			break;
951  		}
952  	}
953  	mutex_unlock(&dcc->cmd_lock);
954  	if (!wakeup || !is_idle(sbi, DISCARD_TIME))
955  		return;
956  wake_up:
957  	dcc->discard_wake = true;
958  	wake_up_interruptible_all(&dcc->discard_wait_queue);
959  }
960  
first_zoned_segno(struct f2fs_sb_info * sbi)961  static inline unsigned int first_zoned_segno(struct f2fs_sb_info *sbi)
962  {
963  	int devi;
964  
965  	for (devi = 0; devi < sbi->s_ndevs; devi++)
966  		if (bdev_is_zoned(FDEV(devi).bdev))
967  			return GET_SEGNO(sbi, FDEV(devi).start_blk);
968  	return 0;
969  }
970