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 #define COMPRESS_ADDR		((block_t)-2)	/* used as compressed data flag */
27 
28 #define F2FS_BYTES_TO_BLK(bytes)	((bytes) >> F2FS_BLKSIZE_BITS)
29 #define F2FS_BLK_TO_BYTES(blk)		((blk) << F2FS_BLKSIZE_BITS)
30 
31 /* 0, 1(node nid), 2(meta nid) are reserved node id */
32 #define F2FS_RESERVED_NODE_NUM		3
33 
34 #define F2FS_ROOT_INO(sbi)	((sbi)->root_ino_num)
35 #define F2FS_NODE_INO(sbi)	((sbi)->node_ino_num)
36 #define F2FS_META_INO(sbi)	((sbi)->meta_ino_num)
37 #define F2FS_COMPRESS_INO(sbi)	(NM_I(sbi)->max_nid)
38 
39 #define F2FS_MAX_QUOTAS		3
40 
41 #define F2FS_ENC_UTF8_12_1	1
42 
43 #define F2FS_IO_SIZE(sbi)	(1 << F2FS_OPTION(sbi).write_io_size_bits) /* Blocks */
44 #define F2FS_IO_SIZE_KB(sbi)	(1 << (F2FS_OPTION(sbi).write_io_size_bits + 2)) /* KB */
45 #define F2FS_IO_SIZE_BYTES(sbi)	(1 << (F2FS_OPTION(sbi).write_io_size_bits + 12)) /* B */
46 #define F2FS_IO_SIZE_BITS(sbi)	(F2FS_OPTION(sbi).write_io_size_bits) /* power of 2 */
47 #define F2FS_IO_SIZE_MASK(sbi)	(F2FS_IO_SIZE(sbi) - 1)
48 #define F2FS_IO_ALIGNED(sbi)	(F2FS_IO_SIZE(sbi) > 1)
49 
50 /* This flag is used by node and meta inodes, and by recovery */
51 #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
52 
53 /*
54  * For further optimization on multi-head logs, on-disk layout supports maximum
55  * 16 logs by default. The number, 16, is expected to cover all the cases
56  * enoughly. The implementaion currently uses no more than 6 logs.
57  * Half the logs are used for nodes, and the other half are used for data.
58  */
59 #define MAX_ACTIVE_LOGS	16
60 #define MAX_ACTIVE_NODE_LOGS	8
61 #define MAX_ACTIVE_DATA_LOGS	8
62 
63 #define VERSION_LEN	256
64 #define MAX_VOLUME_NAME		512
65 #define MAX_PATH_LEN		64
66 #define MAX_DEVICES		8
67 
68 /*
69  * For superblock
70  */
71 struct f2fs_device {
72 	__u8 path[MAX_PATH_LEN];
73 	__le32 total_segments;
74 } __packed;
75 
76 struct f2fs_super_block {
77 	__le32 magic;			/* Magic Number */
78 	__le16 major_ver;		/* Major Version */
79 	__le16 minor_ver;		/* Minor Version */
80 	__le32 log_sectorsize;		/* log2 sector size in bytes */
81 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
82 	__le32 log_blocksize;		/* log2 block size in bytes */
83 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
84 	__le32 segs_per_sec;		/* # of segments per section */
85 	__le32 secs_per_zone;		/* # of sections per zone */
86 	__le32 checksum_offset;		/* checksum offset inside super block */
87 	__le64 block_count;		/* total # of user blocks */
88 	__le32 section_count;		/* total # of sections */
89 	__le32 segment_count;		/* total # of segments */
90 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
91 	__le32 segment_count_sit;	/* # of segments for SIT */
92 	__le32 segment_count_nat;	/* # of segments for NAT */
93 	__le32 segment_count_ssa;	/* # of segments for SSA */
94 	__le32 segment_count_main;	/* # of segments for main area */
95 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
96 	__le32 cp_blkaddr;		/* start block address of checkpoint */
97 	__le32 sit_blkaddr;		/* start block address of SIT */
98 	__le32 nat_blkaddr;		/* start block address of NAT */
99 	__le32 ssa_blkaddr;		/* start block address of SSA */
100 	__le32 main_blkaddr;		/* start block address of main area */
101 	__le32 root_ino;		/* root inode number */
102 	__le32 node_ino;		/* node inode number */
103 	__le32 meta_ino;		/* meta inode number */
104 	__u8 uuid[16];			/* 128-bit uuid for volume */
105 	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
106 	__le32 extension_count;		/* # of extensions below */
107 	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
108 	__le32 cp_payload;
109 	__u8 version[VERSION_LEN];	/* the kernel version */
110 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
111 	__le32 feature;			/* defined features */
112 	__u8 encryption_level;		/* versioning level for encryption */
113 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
114 	struct f2fs_device devs[MAX_DEVICES];	/* device list */
115 	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
116 	__u8 hot_ext_count;		/* # of hot file extension */
117 	__le16  s_encoding;		/* Filename charset encoding */
118 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
119 	__u8 reserved[306];		/* valid reserved region */
120 	__le32 crc;			/* checksum of superblock */
121 } __packed;
122 
123 /*
124  * For checkpoint
125  */
126 #define CP_RESIZEFS_FLAG		0x00004000
127 #define CP_DISABLED_QUICK_FLAG		0x00002000
128 #define CP_DISABLED_FLAG		0x00001000
129 #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
130 #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
131 #define CP_NOCRC_RECOVERY_FLAG	0x00000200
132 #define CP_TRIMMED_FLAG		0x00000100
133 #define CP_NAT_BITS_FLAG	0x00000080
134 #define CP_CRC_RECOVERY_FLAG	0x00000040
135 #define CP_FASTBOOT_FLAG	0x00000020
136 #define CP_FSCK_FLAG		0x00000010
137 #define CP_ERROR_FLAG		0x00000008
138 #define CP_COMPACT_SUM_FLAG	0x00000004
139 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
140 #define CP_UMOUNT_FLAG		0x00000001
141 
142 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
143 
144 struct f2fs_checkpoint {
145 	__le64 checkpoint_ver;		/* checkpoint block version number */
146 	__le64 user_block_count;	/* # of user blocks */
147 	__le64 valid_block_count;	/* # of valid blocks in main area */
148 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
149 	__le32 overprov_segment_count;	/* # of overprovision segments */
150 	__le32 free_segment_count;	/* # of free segments in main area */
151 
152 	/* information of current node segments */
153 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
154 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
155 	/* information of current data segments */
156 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
157 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
158 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
159 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
160 	__le32 cp_pack_start_sum;	/* start block number of data summary */
161 	__le32 valid_node_count;	/* Total number of valid nodes */
162 	__le32 valid_inode_count;	/* Total number of valid inodes */
163 	__le32 next_free_nid;		/* Next free node number */
164 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
165 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
166 	__le32 checksum_offset;		/* checksum offset inside cp block */
167 	__le64 elapsed_time;		/* mounted time */
168 	/* allocation type of current segment */
169 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
170 
171 	/* SIT and NAT version bitmap */
172 	unsigned char sit_nat_version_bitmap[];
173 } __packed;
174 
175 #define CP_CHKSUM_OFFSET	4092	/* default chksum offset in checkpoint */
176 #define CP_MIN_CHKSUM_OFFSET						\
177 	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
178 
179 /*
180  * For orphan inode management
181  */
182 #define F2FS_ORPHANS_PER_BLOCK	1020
183 
184 #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
185 					F2FS_ORPHANS_PER_BLOCK)
186 
187 struct f2fs_orphan_block {
188 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
189 	__le32 reserved;	/* reserved */
190 	__le16 blk_addr;	/* block index in current CP */
191 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
192 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
193 	__le32 check_sum;	/* CRC32 for orphan inode block */
194 } __packed;
195 
196 /*
197  * For NODE structure
198  */
199 struct f2fs_extent {
200 	__le32 fofs;		/* start file offset of the extent */
201 	__le32 blk;		/* start block address of the extent */
202 	__le32 len;		/* length of the extent */
203 } __packed;
204 
205 #define F2FS_NAME_LEN		255
206 /* 200 bytes for inline xattrs by default */
207 #define DEFAULT_INLINE_XATTR_ADDRS	50
208 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
209 #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
210 					get_extra_isize(inode))
211 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
212 #define ADDRS_PER_INODE(inode)	addrs_per_inode(inode)
213 #define DEF_ADDRS_PER_BLOCK	1018	/* Address Pointers in a Direct Block */
214 #define ADDRS_PER_BLOCK(inode)	addrs_per_block(inode)
215 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
216 
217 #define ADDRS_PER_PAGE(page, inode)	\
218 	(IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
219 
220 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
221 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
222 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
223 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
224 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
225 
226 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
227 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
228 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
229 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
230 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
231 #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
232 #define F2FS_PIN_FILE		0x40	/* file should not be gced */
233 #define F2FS_COMPRESS_RELEASED	0x80	/* file released compressed blocks */
234 
235 struct f2fs_inode {
236 	__le16 i_mode;			/* file mode */
237 	__u8 i_advise;			/* file hints */
238 	__u8 i_inline;			/* file inline flags */
239 	__le32 i_uid;			/* user ID */
240 	__le32 i_gid;			/* group ID */
241 	__le32 i_links;			/* links count */
242 	__le64 i_size;			/* file size in bytes */
243 	__le64 i_blocks;		/* file size in blocks */
244 	__le64 i_atime;			/* access time */
245 	__le64 i_ctime;			/* change time */
246 	__le64 i_mtime;			/* modification time */
247 	__le32 i_atime_nsec;		/* access time in nano scale */
248 	__le32 i_ctime_nsec;		/* change time in nano scale */
249 	__le32 i_mtime_nsec;		/* modification time in nano scale */
250 	__le32 i_generation;		/* file version (for NFS) */
251 	union {
252 		__le32 i_current_depth;	/* only for directory depth */
253 		__le16 i_gc_failures;	/*
254 					 * # of gc failures on pinned file.
255 					 * only for regular files.
256 					 */
257 	};
258 	__le32 i_xattr_nid;		/* nid to save xattr */
259 	__le32 i_flags;			/* file attributes */
260 	__le32 i_pino;			/* parent inode number */
261 	__le32 i_namelen;		/* file name length */
262 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
263 	__u8 i_dir_level;		/* dentry_level for large dir */
264 
265 	struct f2fs_extent i_ext;	/* caching a largest extent */
266 
267 	union {
268 		struct {
269 			__le16 i_extra_isize;	/* extra inode attribute size */
270 			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
271 			__le32 i_projid;	/* project id */
272 			__le32 i_inode_checksum;/* inode meta checksum */
273 			__le64 i_crtime;	/* creation time */
274 			__le32 i_crtime_nsec;	/* creation time in nano scale */
275 			__le64 i_compr_blocks;	/* # of compressed blocks */
276 			__u8 i_compress_algorithm;	/* compress algorithm */
277 			__u8 i_log_cluster_size;	/* log of cluster size */
278 			__le16 i_compress_flag;		/* compress flag */
279 						/* 0 bit: chksum flag
280 						 * [10,15] bits: compress level
281 						 */
282 			__le32 i_extra_end[0];	/* for attribute size calculation */
283 		} __packed;
284 		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
285 	};
286 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
287 						double_indirect(1) node id */
288 } __packed;
289 
290 struct direct_node {
291 	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
292 } __packed;
293 
294 struct indirect_node {
295 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
296 } __packed;
297 
298 enum {
299 	COLD_BIT_SHIFT = 0,
300 	FSYNC_BIT_SHIFT,
301 	DENT_BIT_SHIFT,
302 	OFFSET_BIT_SHIFT
303 };
304 
305 #define OFFSET_BIT_MASK		(0x07)	/* (0x01 << OFFSET_BIT_SHIFT) - 1 */
306 
307 struct node_footer {
308 	__le32 nid;		/* node id */
309 	__le32 ino;		/* inode number */
310 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
311 	__le64 cp_ver;		/* checkpoint version */
312 	__le32 next_blkaddr;	/* next node page block address */
313 } __packed;
314 
315 struct f2fs_node {
316 	/* can be one of three types: inode, direct, and indirect types */
317 	union {
318 		struct f2fs_inode i;
319 		struct direct_node dn;
320 		struct indirect_node in;
321 	};
322 	struct node_footer footer;
323 } __packed;
324 
325 /*
326  * For NAT entries
327  */
328 #define NAT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_nat_entry))
329 
330 struct f2fs_nat_entry {
331 	__u8 version;		/* latest version of cached nat entry */
332 	__le32 ino;		/* inode number */
333 	__le32 block_addr;	/* block address */
334 } __packed;
335 
336 struct f2fs_nat_block {
337 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
338 } __packed;
339 
340 /*
341  * For SIT entries
342  *
343  * Each segment is 2MB in size by default so that a bitmap for validity of
344  * there-in blocks should occupy 64 bytes, 512 bits.
345  * Not allow to change this.
346  */
347 #define SIT_VBLOCK_MAP_SIZE 64
348 #define SIT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_sit_entry))
349 
350 /*
351  * F2FS uses 4 bytes to represent block address. As a result, supported size of
352  * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
353  */
354 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
355 
356 /*
357  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
358  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
359  * [9:0] : valid block count
360  */
361 #define SIT_VBLOCKS_SHIFT	10
362 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
363 #define GET_SIT_VBLOCKS(raw_sit)				\
364 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
365 #define GET_SIT_TYPE(raw_sit)					\
366 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
367 	 >> SIT_VBLOCKS_SHIFT)
368 
369 struct f2fs_sit_entry {
370 	__le16 vblocks;				/* reference above */
371 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
372 	__le64 mtime;				/* segment age for cleaning */
373 } __packed;
374 
375 struct f2fs_sit_block {
376 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
377 } __packed;
378 
379 /*
380  * For segment summary
381  *
382  * One summary block contains exactly 512 summary entries, which represents
383  * exactly 2MB segment by default. Not allow to change the basic units.
384  *
385  * NOTE: For initializing fields, you must use set_summary
386  *
387  * - If data page, nid represents dnode's nid
388  * - If node page, nid represents the node page's nid.
389  *
390  * The ofs_in_node is used by only data page. It represents offset
391  * from node's page's beginning to get a data block address.
392  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
393  */
394 #define ENTRIES_IN_SUM		512
395 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
396 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
397 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
398 
399 /* a summary entry for a 4KB-sized block in a segment */
400 struct f2fs_summary {
401 	__le32 nid;		/* parent node id */
402 	union {
403 		__u8 reserved[3];
404 		struct {
405 			__u8 version;		/* node version number */
406 			__le16 ofs_in_node;	/* block index in parent node */
407 		} __packed;
408 	};
409 } __packed;
410 
411 /* summary block type, node or data, is stored to the summary_footer */
412 #define SUM_TYPE_NODE		(1)
413 #define SUM_TYPE_DATA		(0)
414 
415 struct summary_footer {
416 	unsigned char entry_type;	/* SUM_TYPE_XXX */
417 	__le32 check_sum;		/* summary checksum */
418 } __packed;
419 
420 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
421 				SUM_ENTRY_SIZE)
422 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
423 				sizeof(struct nat_journal_entry))
424 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
425 				sizeof(struct nat_journal_entry))
426 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
427 				sizeof(struct sit_journal_entry))
428 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
429 				sizeof(struct sit_journal_entry))
430 
431 /* Reserved area should make size of f2fs_extra_info equals to
432  * that of nat_journal and sit_journal.
433  */
434 #define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
435 
436 /*
437  * frequently updated NAT/SIT entries can be stored in the spare area in
438  * summary blocks
439  */
440 enum {
441 	NAT_JOURNAL = 0,
442 	SIT_JOURNAL
443 };
444 
445 struct nat_journal_entry {
446 	__le32 nid;
447 	struct f2fs_nat_entry ne;
448 } __packed;
449 
450 struct nat_journal {
451 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
452 	__u8 reserved[NAT_JOURNAL_RESERVED];
453 } __packed;
454 
455 struct sit_journal_entry {
456 	__le32 segno;
457 	struct f2fs_sit_entry se;
458 } __packed;
459 
460 struct sit_journal {
461 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
462 	__u8 reserved[SIT_JOURNAL_RESERVED];
463 } __packed;
464 
465 struct f2fs_extra_info {
466 	__le64 kbytes_written;
467 	__u8 reserved[EXTRA_INFO_RESERVED];
468 } __packed;
469 
470 struct f2fs_journal {
471 	union {
472 		__le16 n_nats;
473 		__le16 n_sits;
474 	};
475 	/* spare area is used by NAT or SIT journals or extra info */
476 	union {
477 		struct nat_journal nat_j;
478 		struct sit_journal sit_j;
479 		struct f2fs_extra_info info;
480 	};
481 } __packed;
482 
483 /* 4KB-sized summary block structure */
484 struct f2fs_summary_block {
485 	struct f2fs_summary entries[ENTRIES_IN_SUM];
486 	struct f2fs_journal journal;
487 	struct summary_footer footer;
488 } __packed;
489 
490 /*
491  * For directory operations
492  */
493 #define F2FS_DOT_HASH		0
494 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
495 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
496 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
497 
498 typedef __le32	f2fs_hash_t;
499 
500 /* One directory entry slot covers 8bytes-long file name */
501 #define F2FS_SLOT_LEN		8
502 #define F2FS_SLOT_LEN_BITS	3
503 
504 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
505 
506 /* MAX level for dir lookup */
507 #define MAX_DIR_HASH_DEPTH	63
508 
509 /* MAX buckets in one level of dir */
510 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
511 
512 /*
513  * space utilization of regular dentry and inline dentry (w/o extra reservation)
514  *		regular dentry		inline dentry (def)	inline dentry (min)
515  * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
516  * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
517  * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
518  * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
519  * total	4096			3488			40
520  *
521  * Note: there are more reserved space in inline dentry than in regular
522  * dentry, when converting inline dentry we should handle this carefully.
523  */
524 #define NR_DENTRY_IN_BLOCK	214	/* the number of dentry in a block */
525 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
526 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
527 					BITS_PER_BYTE)
528 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
529 				F2FS_SLOT_LEN) * \
530 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
531 #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
532 
533 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
534 struct f2fs_dir_entry {
535 	__le32 hash_code;	/* hash code of file name */
536 	__le32 ino;		/* inode number */
537 	__le16 name_len;	/* length of file name */
538 	__u8 file_type;		/* file type */
539 } __packed;
540 
541 /* 4KB-sized directory entry block */
542 struct f2fs_dentry_block {
543 	/* validity bitmap for directory entries in each block */
544 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
545 	__u8 reserved[SIZE_OF_RESERVED];
546 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
547 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
548 } __packed;
549 
550 /* file types used in inode_info->flags */
551 enum {
552 	F2FS_FT_UNKNOWN,
553 	F2FS_FT_REG_FILE,
554 	F2FS_FT_DIR,
555 	F2FS_FT_CHRDEV,
556 	F2FS_FT_BLKDEV,
557 	F2FS_FT_FIFO,
558 	F2FS_FT_SOCK,
559 	F2FS_FT_SYMLINK,
560 	F2FS_FT_MAX
561 };
562 
563 #define S_SHIFT 12
564 
565 #define	F2FS_DEF_PROJID		0	/* default project ID */
566 
567 #endif  /* _LINUX_F2FS_FS_H */
568