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