xref: /linux/include/linux/f2fs_fs.h (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
1 // SPDX-License-Identifier: GPL-2.0
2 /**
3  * include/linux/f2fs_fs.h
4  *
5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6  *             http://www.samsung.com/
7  */
8 #ifndef _LINUX_F2FS_FS_H
9 #define _LINUX_F2FS_FS_H
10 
11 #include <linux/pagemap.h>
12 #include <linux/types.h>
13 
14 #define F2FS_SUPER_OFFSET		1024	/* byte-size offset */
15 #define F2FS_MIN_LOG_SECTOR_SIZE	9	/* 9 bits for 512 bytes */
16 #define F2FS_MAX_LOG_SECTOR_SIZE	12	/* 12 bits for 4096 bytes */
17 #define F2FS_LOG_SECTORS_PER_BLOCK	3	/* log number for sector/blk */
18 #define F2FS_BLKSIZE			4096	/* support only 4KB block */
19 #define F2FS_BLKSIZE_BITS		12	/* bits for F2FS_BLKSIZE */
20 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
21 #define F2FS_EXTENSION_LEN		8	/* max size of extension */
22 #define F2FS_BLK_ALIGN(x)	(((x) + F2FS_BLKSIZE - 1) >> F2FS_BLKSIZE_BITS)
23 
24 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
25 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
26 
27 #define F2FS_BYTES_TO_BLK(bytes)	((bytes) >> F2FS_BLKSIZE_BITS)
28 #define F2FS_BLK_TO_BYTES(blk)		((blk) << F2FS_BLKSIZE_BITS)
29 
30 /* 0, 1(node nid), 2(meta nid) are reserved node id */
31 #define F2FS_RESERVED_NODE_NUM		3
32 
33 #define F2FS_ROOT_INO(sbi)	((sbi)->root_ino_num)
34 #define F2FS_NODE_INO(sbi)	((sbi)->node_ino_num)
35 #define F2FS_META_INO(sbi)	((sbi)->meta_ino_num)
36 
37 #define F2FS_MAX_QUOTAS		3
38 
39 #define F2FS_IO_SIZE(sbi)	(1 << F2FS_OPTION(sbi).write_io_size_bits) /* Blocks */
40 #define F2FS_IO_SIZE_KB(sbi)	(1 << (F2FS_OPTION(sbi).write_io_size_bits + 2)) /* KB */
41 #define F2FS_IO_SIZE_BYTES(sbi)	(1 << (F2FS_OPTION(sbi).write_io_size_bits + 12)) /* B */
42 #define F2FS_IO_SIZE_BITS(sbi)	(F2FS_OPTION(sbi).write_io_size_bits) /* power of 2 */
43 #define F2FS_IO_SIZE_MASK(sbi)	(F2FS_IO_SIZE(sbi) - 1)
44 
45 /* This flag is used by node and meta inodes, and by recovery */
46 #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
47 
48 /*
49  * For further optimization on multi-head logs, on-disk layout supports maximum
50  * 16 logs by default. The number, 16, is expected to cover all the cases
51  * enoughly. The implementaion currently uses no more than 6 logs.
52  * Half the logs are used for nodes, and the other half are used for data.
53  */
54 #define MAX_ACTIVE_LOGS	16
55 #define MAX_ACTIVE_NODE_LOGS	8
56 #define MAX_ACTIVE_DATA_LOGS	8
57 
58 #define VERSION_LEN	256
59 #define MAX_VOLUME_NAME		512
60 #define MAX_PATH_LEN		64
61 #define MAX_DEVICES		8
62 
63 /*
64  * For superblock
65  */
66 struct f2fs_device {
67 	__u8 path[MAX_PATH_LEN];
68 	__le32 total_segments;
69 } __packed;
70 
71 struct f2fs_super_block {
72 	__le32 magic;			/* Magic Number */
73 	__le16 major_ver;		/* Major Version */
74 	__le16 minor_ver;		/* Minor Version */
75 	__le32 log_sectorsize;		/* log2 sector size in bytes */
76 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
77 	__le32 log_blocksize;		/* log2 block size in bytes */
78 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
79 	__le32 segs_per_sec;		/* # of segments per section */
80 	__le32 secs_per_zone;		/* # of sections per zone */
81 	__le32 checksum_offset;		/* checksum offset inside super block */
82 	__le64 block_count;		/* total # of user blocks */
83 	__le32 section_count;		/* total # of sections */
84 	__le32 segment_count;		/* total # of segments */
85 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
86 	__le32 segment_count_sit;	/* # of segments for SIT */
87 	__le32 segment_count_nat;	/* # of segments for NAT */
88 	__le32 segment_count_ssa;	/* # of segments for SSA */
89 	__le32 segment_count_main;	/* # of segments for main area */
90 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
91 	__le32 cp_blkaddr;		/* start block address of checkpoint */
92 	__le32 sit_blkaddr;		/* start block address of SIT */
93 	__le32 nat_blkaddr;		/* start block address of NAT */
94 	__le32 ssa_blkaddr;		/* start block address of SSA */
95 	__le32 main_blkaddr;		/* start block address of main area */
96 	__le32 root_ino;		/* root inode number */
97 	__le32 node_ino;		/* node inode number */
98 	__le32 meta_ino;		/* meta inode number */
99 	__u8 uuid[16];			/* 128-bit uuid for volume */
100 	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
101 	__le32 extension_count;		/* # of extensions below */
102 	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
103 	__le32 cp_payload;
104 	__u8 version[VERSION_LEN];	/* the kernel version */
105 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
106 	__le32 feature;			/* defined features */
107 	__u8 encryption_level;		/* versioning level for encryption */
108 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
109 	struct f2fs_device devs[MAX_DEVICES];	/* device list */
110 	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
111 	__u8 hot_ext_count;		/* # of hot file extension */
112 	__u8 reserved[310];		/* valid reserved region */
113 	__le32 crc;			/* checksum of superblock */
114 } __packed;
115 
116 /*
117  * For checkpoint
118  */
119 #define CP_DISABLED_QUICK_FLAG		0x00002000
120 #define CP_DISABLED_FLAG		0x00001000
121 #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
122 #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
123 #define CP_NOCRC_RECOVERY_FLAG	0x00000200
124 #define CP_TRIMMED_FLAG		0x00000100
125 #define CP_NAT_BITS_FLAG	0x00000080
126 #define CP_CRC_RECOVERY_FLAG	0x00000040
127 #define CP_FASTBOOT_FLAG	0x00000020
128 #define CP_FSCK_FLAG		0x00000010
129 #define CP_ERROR_FLAG		0x00000008
130 #define CP_COMPACT_SUM_FLAG	0x00000004
131 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
132 #define CP_UMOUNT_FLAG		0x00000001
133 
134 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
135 
136 struct f2fs_checkpoint {
137 	__le64 checkpoint_ver;		/* checkpoint block version number */
138 	__le64 user_block_count;	/* # of user blocks */
139 	__le64 valid_block_count;	/* # of valid blocks in main area */
140 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
141 	__le32 overprov_segment_count;	/* # of overprovision segments */
142 	__le32 free_segment_count;	/* # of free segments in main area */
143 
144 	/* information of current node segments */
145 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
146 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
147 	/* information of current data segments */
148 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
149 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
150 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
151 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
152 	__le32 cp_pack_start_sum;	/* start block number of data summary */
153 	__le32 valid_node_count;	/* Total number of valid nodes */
154 	__le32 valid_inode_count;	/* Total number of valid inodes */
155 	__le32 next_free_nid;		/* Next free node number */
156 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
157 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
158 	__le32 checksum_offset;		/* checksum offset inside cp block */
159 	__le64 elapsed_time;		/* mounted time */
160 	/* allocation type of current segment */
161 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
162 
163 	/* SIT and NAT version bitmap */
164 	unsigned char sit_nat_version_bitmap[1];
165 } __packed;
166 
167 #define CP_CHKSUM_OFFSET	4092	/* default chksum offset in checkpoint */
168 #define CP_MIN_CHKSUM_OFFSET						\
169 	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
170 
171 /*
172  * For orphan inode management
173  */
174 #define F2FS_ORPHANS_PER_BLOCK	1020
175 
176 #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
177 					F2FS_ORPHANS_PER_BLOCK)
178 
179 struct f2fs_orphan_block {
180 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
181 	__le32 reserved;	/* reserved */
182 	__le16 blk_addr;	/* block index in current CP */
183 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
184 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
185 	__le32 check_sum;	/* CRC32 for orphan inode block */
186 } __packed;
187 
188 /*
189  * For NODE structure
190  */
191 struct f2fs_extent {
192 	__le32 fofs;		/* start file offset of the extent */
193 	__le32 blk;		/* start block address of the extent */
194 	__le32 len;		/* length of the extent */
195 } __packed;
196 
197 #define F2FS_NAME_LEN		255
198 /* 200 bytes for inline xattrs by default */
199 #define DEFAULT_INLINE_XATTR_ADDRS	50
200 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
201 #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
202 					get_extra_isize(inode))
203 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
204 #define ADDRS_PER_INODE(inode)	addrs_per_inode(inode)
205 #define DEF_ADDRS_PER_BLOCK	1018	/* Address Pointers in a Direct Block */
206 #define ADDRS_PER_BLOCK(inode)	addrs_per_block(inode)
207 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
208 
209 #define ADDRS_PER_PAGE(page, inode)	\
210 	(IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
211 
212 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
213 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
214 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
215 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
216 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
217 
218 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
219 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
220 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
221 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
222 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
223 #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
224 #define F2FS_PIN_FILE		0x40	/* file should not be gced */
225 
226 struct f2fs_inode {
227 	__le16 i_mode;			/* file mode */
228 	__u8 i_advise;			/* file hints */
229 	__u8 i_inline;			/* file inline flags */
230 	__le32 i_uid;			/* user ID */
231 	__le32 i_gid;			/* group ID */
232 	__le32 i_links;			/* links count */
233 	__le64 i_size;			/* file size in bytes */
234 	__le64 i_blocks;		/* file size in blocks */
235 	__le64 i_atime;			/* access time */
236 	__le64 i_ctime;			/* change time */
237 	__le64 i_mtime;			/* modification time */
238 	__le32 i_atime_nsec;		/* access time in nano scale */
239 	__le32 i_ctime_nsec;		/* change time in nano scale */
240 	__le32 i_mtime_nsec;		/* modification time in nano scale */
241 	__le32 i_generation;		/* file version (for NFS) */
242 	union {
243 		__le32 i_current_depth;	/* only for directory depth */
244 		__le16 i_gc_failures;	/*
245 					 * # of gc failures on pinned file.
246 					 * only for regular files.
247 					 */
248 	};
249 	__le32 i_xattr_nid;		/* nid to save xattr */
250 	__le32 i_flags;			/* file attributes */
251 	__le32 i_pino;			/* parent inode number */
252 	__le32 i_namelen;		/* file name length */
253 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
254 	__u8 i_dir_level;		/* dentry_level for large dir */
255 
256 	struct f2fs_extent i_ext;	/* caching a largest extent */
257 
258 	union {
259 		struct {
260 			__le16 i_extra_isize;	/* extra inode attribute size */
261 			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
262 			__le32 i_projid;	/* project id */
263 			__le32 i_inode_checksum;/* inode meta checksum */
264 			__le64 i_crtime;	/* creation time */
265 			__le32 i_crtime_nsec;	/* creation time in nano scale */
266 			__le32 i_extra_end[0];	/* for attribute size calculation */
267 		} __packed;
268 		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
269 	};
270 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
271 						double_indirect(1) node id */
272 } __packed;
273 
274 struct direct_node {
275 	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
276 } __packed;
277 
278 struct indirect_node {
279 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
280 } __packed;
281 
282 enum {
283 	COLD_BIT_SHIFT = 0,
284 	FSYNC_BIT_SHIFT,
285 	DENT_BIT_SHIFT,
286 	OFFSET_BIT_SHIFT
287 };
288 
289 #define OFFSET_BIT_MASK		(0x07)	/* (0x01 << OFFSET_BIT_SHIFT) - 1 */
290 
291 struct node_footer {
292 	__le32 nid;		/* node id */
293 	__le32 ino;		/* inode number */
294 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
295 	__le64 cp_ver;		/* checkpoint version */
296 	__le32 next_blkaddr;	/* next node page block address */
297 } __packed;
298 
299 struct f2fs_node {
300 	/* can be one of three types: inode, direct, and indirect types */
301 	union {
302 		struct f2fs_inode i;
303 		struct direct_node dn;
304 		struct indirect_node in;
305 	};
306 	struct node_footer footer;
307 } __packed;
308 
309 /*
310  * For NAT entries
311  */
312 #define NAT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_nat_entry))
313 
314 struct f2fs_nat_entry {
315 	__u8 version;		/* latest version of cached nat entry */
316 	__le32 ino;		/* inode number */
317 	__le32 block_addr;	/* block address */
318 } __packed;
319 
320 struct f2fs_nat_block {
321 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
322 } __packed;
323 
324 /*
325  * For SIT entries
326  *
327  * Each segment is 2MB in size by default so that a bitmap for validity of
328  * there-in blocks should occupy 64 bytes, 512 bits.
329  * Not allow to change this.
330  */
331 #define SIT_VBLOCK_MAP_SIZE 64
332 #define SIT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_sit_entry))
333 
334 /*
335  * F2FS uses 4 bytes to represent block address. As a result, supported size of
336  * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
337  */
338 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
339 
340 /*
341  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
342  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
343  * [9:0] : valid block count
344  */
345 #define SIT_VBLOCKS_SHIFT	10
346 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
347 #define GET_SIT_VBLOCKS(raw_sit)				\
348 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
349 #define GET_SIT_TYPE(raw_sit)					\
350 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
351 	 >> SIT_VBLOCKS_SHIFT)
352 
353 struct f2fs_sit_entry {
354 	__le16 vblocks;				/* reference above */
355 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
356 	__le64 mtime;				/* segment age for cleaning */
357 } __packed;
358 
359 struct f2fs_sit_block {
360 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
361 } __packed;
362 
363 /*
364  * For segment summary
365  *
366  * One summary block contains exactly 512 summary entries, which represents
367  * exactly 2MB segment by default. Not allow to change the basic units.
368  *
369  * NOTE: For initializing fields, you must use set_summary
370  *
371  * - If data page, nid represents dnode's nid
372  * - If node page, nid represents the node page's nid.
373  *
374  * The ofs_in_node is used by only data page. It represents offset
375  * from node's page's beginning to get a data block address.
376  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
377  */
378 #define ENTRIES_IN_SUM		512
379 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
380 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
381 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
382 
383 /* a summary entry for a 4KB-sized block in a segment */
384 struct f2fs_summary {
385 	__le32 nid;		/* parent node id */
386 	union {
387 		__u8 reserved[3];
388 		struct {
389 			__u8 version;		/* node version number */
390 			__le16 ofs_in_node;	/* block index in parent node */
391 		} __packed;
392 	};
393 } __packed;
394 
395 /* summary block type, node or data, is stored to the summary_footer */
396 #define SUM_TYPE_NODE		(1)
397 #define SUM_TYPE_DATA		(0)
398 
399 struct summary_footer {
400 	unsigned char entry_type;	/* SUM_TYPE_XXX */
401 	__le32 check_sum;		/* summary checksum */
402 } __packed;
403 
404 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
405 				SUM_ENTRY_SIZE)
406 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
407 				sizeof(struct nat_journal_entry))
408 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
409 				sizeof(struct nat_journal_entry))
410 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
411 				sizeof(struct sit_journal_entry))
412 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
413 				sizeof(struct sit_journal_entry))
414 
415 /* Reserved area should make size of f2fs_extra_info equals to
416  * that of nat_journal and sit_journal.
417  */
418 #define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
419 
420 /*
421  * frequently updated NAT/SIT entries can be stored in the spare area in
422  * summary blocks
423  */
424 enum {
425 	NAT_JOURNAL = 0,
426 	SIT_JOURNAL
427 };
428 
429 struct nat_journal_entry {
430 	__le32 nid;
431 	struct f2fs_nat_entry ne;
432 } __packed;
433 
434 struct nat_journal {
435 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
436 	__u8 reserved[NAT_JOURNAL_RESERVED];
437 } __packed;
438 
439 struct sit_journal_entry {
440 	__le32 segno;
441 	struct f2fs_sit_entry se;
442 } __packed;
443 
444 struct sit_journal {
445 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
446 	__u8 reserved[SIT_JOURNAL_RESERVED];
447 } __packed;
448 
449 struct f2fs_extra_info {
450 	__le64 kbytes_written;
451 	__u8 reserved[EXTRA_INFO_RESERVED];
452 } __packed;
453 
454 struct f2fs_journal {
455 	union {
456 		__le16 n_nats;
457 		__le16 n_sits;
458 	};
459 	/* spare area is used by NAT or SIT journals or extra info */
460 	union {
461 		struct nat_journal nat_j;
462 		struct sit_journal sit_j;
463 		struct f2fs_extra_info info;
464 	};
465 } __packed;
466 
467 /* 4KB-sized summary block structure */
468 struct f2fs_summary_block {
469 	struct f2fs_summary entries[ENTRIES_IN_SUM];
470 	struct f2fs_journal journal;
471 	struct summary_footer footer;
472 } __packed;
473 
474 /*
475  * For directory operations
476  */
477 #define F2FS_DOT_HASH		0
478 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
479 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
480 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
481 
482 typedef __le32	f2fs_hash_t;
483 
484 /* One directory entry slot covers 8bytes-long file name */
485 #define F2FS_SLOT_LEN		8
486 #define F2FS_SLOT_LEN_BITS	3
487 
488 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
489 
490 /* MAX level for dir lookup */
491 #define MAX_DIR_HASH_DEPTH	63
492 
493 /* MAX buckets in one level of dir */
494 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
495 
496 /*
497  * space utilization of regular dentry and inline dentry (w/o extra reservation)
498  *		regular dentry		inline dentry (def)	inline dentry (min)
499  * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
500  * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
501  * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
502  * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
503  * total	4096			3488			40
504  *
505  * Note: there are more reserved space in inline dentry than in regular
506  * dentry, when converting inline dentry we should handle this carefully.
507  */
508 #define NR_DENTRY_IN_BLOCK	214	/* the number of dentry in a block */
509 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
510 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
511 					BITS_PER_BYTE)
512 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
513 				F2FS_SLOT_LEN) * \
514 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
515 #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
516 
517 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
518 struct f2fs_dir_entry {
519 	__le32 hash_code;	/* hash code of file name */
520 	__le32 ino;		/* inode number */
521 	__le16 name_len;	/* length of file name */
522 	__u8 file_type;		/* file type */
523 } __packed;
524 
525 /* 4KB-sized directory entry block */
526 struct f2fs_dentry_block {
527 	/* validity bitmap for directory entries in each block */
528 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
529 	__u8 reserved[SIZE_OF_RESERVED];
530 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
531 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
532 } __packed;
533 
534 /* file types used in inode_info->flags */
535 enum {
536 	F2FS_FT_UNKNOWN,
537 	F2FS_FT_REG_FILE,
538 	F2FS_FT_DIR,
539 	F2FS_FT_CHRDEV,
540 	F2FS_FT_BLKDEV,
541 	F2FS_FT_FIFO,
542 	F2FS_FT_SOCK,
543 	F2FS_FT_SYMLINK,
544 	F2FS_FT_MAX
545 };
546 
547 #define S_SHIFT 12
548 
549 #define	F2FS_DEF_PROJID		0	/* default project ID */
550 
551 #endif  /* _LINUX_F2FS_FS_H */
552