xref: /linux/include/linux/f2fs_fs.h (revision 86d563ac5fb0c6f404e82692581bb67a6f35e5de)
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	PAGE_SHIFT	/* Max is Block Size */
17 #define F2FS_LOG_SECTORS_PER_BLOCK	(PAGE_SHIFT - 9) /* log number for sector/blk */
18 #define F2FS_BLKSIZE			PAGE_SIZE /* support only block == page */
19 #define F2FS_BLKSIZE_BITS		PAGE_SHIFT /* bits for F2FS_BLKSIZE */
20 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
21 #define F2FS_EXTENSION_LEN		8	/* max size of extension */
22 
23 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
24 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
25 #define COMPRESS_ADDR		((block_t)-2)	/* used as compressed data flag */
26 
27 #define F2FS_BLKSIZE_MASK		(F2FS_BLKSIZE - 1)
28 #define F2FS_BYTES_TO_BLK(bytes)	((unsigned long long)(bytes) >> F2FS_BLKSIZE_BITS)
29 #define F2FS_BLK_TO_BYTES(blk)		((unsigned long long)(blk) << F2FS_BLKSIZE_BITS)
30 #define F2FS_BLK_END_BYTES(blk)		(F2FS_BLK_TO_BYTES(blk + 1) - 1)
31 #define F2FS_BLK_ALIGN(x)		(F2FS_BYTES_TO_BLK((x) + F2FS_BLKSIZE - 1))
32 
33 /* 0, 1(node nid), 2(meta nid) are reserved node id */
34 #define F2FS_RESERVED_NODE_NUM		3
35 
36 #define F2FS_ROOT_INO(sbi)	((sbi)->root_ino_num)
37 #define F2FS_NODE_INO(sbi)	((sbi)->node_ino_num)
38 #define F2FS_META_INO(sbi)	((sbi)->meta_ino_num)
39 #define F2FS_COMPRESS_INO(sbi)	(NM_I(sbi)->max_nid)
40 
41 #define F2FS_MAX_QUOTAS		3
42 
43 #define F2FS_ENC_UTF8_12_1	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 /* reason of stop_checkpoint */
72 enum stop_cp_reason {
73 	STOP_CP_REASON_SHUTDOWN,
74 	STOP_CP_REASON_FAULT_INJECT,
75 	STOP_CP_REASON_META_PAGE,
76 	STOP_CP_REASON_WRITE_FAIL,
77 	STOP_CP_REASON_CORRUPTED_SUMMARY,
78 	STOP_CP_REASON_UPDATE_INODE,
79 	STOP_CP_REASON_FLUSH_FAIL,
80 	STOP_CP_REASON_NO_SEGMENT,
81 	STOP_CP_REASON_CORRUPTED_FREE_BITMAP,
82 	STOP_CP_REASON_CORRUPTED_NID,
83 	STOP_CP_REASON_MAX,
84 };
85 
86 #define	MAX_STOP_REASON			32
87 
88 /* detail reason for EFSCORRUPTED */
89 enum f2fs_error {
90 	ERROR_CORRUPTED_CLUSTER,
91 	ERROR_FAIL_DECOMPRESSION,
92 	ERROR_INVALID_BLKADDR,
93 	ERROR_CORRUPTED_DIRENT,
94 	ERROR_CORRUPTED_INODE,
95 	ERROR_INCONSISTENT_SUMMARY,
96 	ERROR_INCONSISTENT_FOOTER,
97 	ERROR_INCONSISTENT_SUM_TYPE,
98 	ERROR_CORRUPTED_JOURNAL,
99 	ERROR_INCONSISTENT_NODE_COUNT,
100 	ERROR_INCONSISTENT_BLOCK_COUNT,
101 	ERROR_INVALID_CURSEG,
102 	ERROR_INCONSISTENT_SIT,
103 	ERROR_CORRUPTED_VERITY_XATTR,
104 	ERROR_CORRUPTED_XATTR,
105 	ERROR_INVALID_NODE_REFERENCE,
106 	ERROR_INCONSISTENT_NAT,
107 	ERROR_MAX,
108 };
109 
110 #define MAX_F2FS_ERRORS			16
111 
112 struct f2fs_super_block {
113 	__le32 magic;			/* Magic Number */
114 	__le16 major_ver;		/* Major Version */
115 	__le16 minor_ver;		/* Minor Version */
116 	__le32 log_sectorsize;		/* log2 sector size in bytes */
117 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
118 	__le32 log_blocksize;		/* log2 block size in bytes */
119 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
120 	__le32 segs_per_sec;		/* # of segments per section */
121 	__le32 secs_per_zone;		/* # of sections per zone */
122 	__le32 checksum_offset;		/* checksum offset inside super block */
123 	__le64 block_count;		/* total # of user blocks */
124 	__le32 section_count;		/* total # of sections */
125 	__le32 segment_count;		/* total # of segments */
126 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
127 	__le32 segment_count_sit;	/* # of segments for SIT */
128 	__le32 segment_count_nat;	/* # of segments for NAT */
129 	__le32 segment_count_ssa;	/* # of segments for SSA */
130 	__le32 segment_count_main;	/* # of segments for main area */
131 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
132 	__le32 cp_blkaddr;		/* start block address of checkpoint */
133 	__le32 sit_blkaddr;		/* start block address of SIT */
134 	__le32 nat_blkaddr;		/* start block address of NAT */
135 	__le32 ssa_blkaddr;		/* start block address of SSA */
136 	__le32 main_blkaddr;		/* start block address of main area */
137 	__le32 root_ino;		/* root inode number */
138 	__le32 node_ino;		/* node inode number */
139 	__le32 meta_ino;		/* meta inode number */
140 	__u8 uuid[16];			/* 128-bit uuid for volume */
141 	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
142 	__le32 extension_count;		/* # of extensions below */
143 	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
144 	__le32 cp_payload;
145 	__u8 version[VERSION_LEN];	/* the kernel version */
146 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
147 	__le32 feature;			/* defined features */
148 	__u8 encryption_level;		/* versioning level for encryption */
149 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
150 	struct f2fs_device devs[MAX_DEVICES];	/* device list */
151 	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
152 	__u8 hot_ext_count;		/* # of hot file extension */
153 	__le16  s_encoding;		/* Filename charset encoding */
154 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
155 	__u8 s_stop_reason[MAX_STOP_REASON];	/* stop checkpoint reason */
156 	__u8 s_errors[MAX_F2FS_ERRORS];		/* reason of image corrupts */
157 	__u8 reserved[258];		/* valid reserved region */
158 	__le32 crc;			/* checksum of superblock */
159 } __packed;
160 
161 /*
162  * For checkpoint
163  */
164 #define CP_RESIZEFS_FLAG		0x00004000
165 #define CP_DISABLED_QUICK_FLAG		0x00002000
166 #define CP_DISABLED_FLAG		0x00001000
167 #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
168 #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
169 #define CP_NOCRC_RECOVERY_FLAG	0x00000200
170 #define CP_TRIMMED_FLAG		0x00000100
171 #define CP_NAT_BITS_FLAG	0x00000080
172 #define CP_CRC_RECOVERY_FLAG	0x00000040
173 #define CP_FASTBOOT_FLAG	0x00000020
174 #define CP_FSCK_FLAG		0x00000010
175 #define CP_ERROR_FLAG		0x00000008
176 #define CP_COMPACT_SUM_FLAG	0x00000004
177 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
178 #define CP_UMOUNT_FLAG		0x00000001
179 
180 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
181 
182 struct f2fs_checkpoint {
183 	__le64 checkpoint_ver;		/* checkpoint block version number */
184 	__le64 user_block_count;	/* # of user blocks */
185 	__le64 valid_block_count;	/* # of valid blocks in main area */
186 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
187 	__le32 overprov_segment_count;	/* # of overprovision segments */
188 	__le32 free_segment_count;	/* # of free segments in main area */
189 
190 	/* information of current node segments */
191 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
192 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
193 	/* information of current data segments */
194 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
195 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
196 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
197 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
198 	__le32 cp_pack_start_sum;	/* start block number of data summary */
199 	__le32 valid_node_count;	/* Total number of valid nodes */
200 	__le32 valid_inode_count;	/* Total number of valid inodes */
201 	__le32 next_free_nid;		/* Next free node number */
202 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
203 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
204 	__le32 checksum_offset;		/* checksum offset inside cp block */
205 	__le64 elapsed_time;		/* mounted time */
206 	/* allocation type of current segment */
207 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
208 
209 	/* SIT and NAT version bitmap */
210 	unsigned char sit_nat_version_bitmap[];
211 } __packed;
212 
213 #define CP_CHKSUM_OFFSET	(F2FS_BLKSIZE - sizeof(__le32))	/* default chksum offset in checkpoint */
214 #define CP_MIN_CHKSUM_OFFSET						\
215 	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
216 
217 /*
218  * For orphan inode management
219  */
220 #define F2FS_ORPHANS_PER_BLOCK	((F2FS_BLKSIZE - 4 * sizeof(__le32)) / sizeof(__le32))
221 
222 #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
223 					F2FS_ORPHANS_PER_BLOCK)
224 
225 struct f2fs_orphan_block {
226 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
227 	__le32 reserved;	/* reserved */
228 	__le16 blk_addr;	/* block index in current CP */
229 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
230 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
231 	__le32 check_sum;	/* CRC32 for orphan inode block */
232 } __packed;
233 
234 /*
235  * For NODE structure
236  */
237 struct f2fs_extent {
238 	__le32 fofs;		/* start file offset of the extent */
239 	__le32 blk;		/* start block address of the extent */
240 	__le32 len;		/* length of the extent */
241 } __packed;
242 
243 #define F2FS_NAME_LEN		255
244 /* 200 bytes for inline xattrs by default */
245 #define DEFAULT_INLINE_XATTR_ADDRS	50
246 
247 #define OFFSET_OF_END_OF_I_EXT		360
248 #define SIZE_OF_I_NID			20
249 
250 struct node_footer {
251 	__le32 nid;		/* node id */
252 	__le32 ino;		/* inode number */
253 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
254 	__le64 cp_ver;		/* checkpoint version */
255 	__le32 next_blkaddr;	/* next node page block address */
256 } __packed;
257 
258 /* Address Pointers in an Inode */
259 #define DEF_ADDRS_PER_INODE	((F2FS_BLKSIZE - OFFSET_OF_END_OF_I_EXT	\
260 					- SIZE_OF_I_NID	\
261 					- sizeof(struct node_footer)) / sizeof(__le32))
262 #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
263 					get_extra_isize(inode))
264 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
265 #define ADDRS_PER_INODE(inode)	addrs_per_page(inode, true)
266 /* Address Pointers in a Direct Block */
267 #define DEF_ADDRS_PER_BLOCK	((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
268 #define ADDRS_PER_BLOCK(inode)	addrs_per_page(inode, false)
269 /* Node IDs in an Indirect Block */
270 #define NIDS_PER_BLOCK		((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
271 
272 #define ADDRS_PER_PAGE(folio, inode)	(addrs_per_page(inode, IS_INODE(folio)))
273 
274 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
275 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
276 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
277 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
278 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
279 
280 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
281 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
282 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
283 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
284 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries (obsolete) */
285 #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
286 #define F2FS_PIN_FILE		0x40	/* file should not be gced */
287 #define F2FS_COMPRESS_RELEASED	0x80	/* file released compressed blocks */
288 
289 struct f2fs_inode {
290 	__le16 i_mode;			/* file mode */
291 	__u8 i_advise;			/* file hints */
292 	__u8 i_inline;			/* file inline flags */
293 	__le32 i_uid;			/* user ID */
294 	__le32 i_gid;			/* group ID */
295 	__le32 i_links;			/* links count */
296 	__le64 i_size;			/* file size in bytes */
297 	__le64 i_blocks;		/* file size in blocks */
298 	__le64 i_atime;			/* access time */
299 	__le64 i_ctime;			/* change time */
300 	__le64 i_mtime;			/* modification time */
301 	__le32 i_atime_nsec;		/* access time in nano scale */
302 	__le32 i_ctime_nsec;		/* change time in nano scale */
303 	__le32 i_mtime_nsec;		/* modification time in nano scale */
304 	__le32 i_generation;		/* file version (for NFS) */
305 	union {
306 		__le32 i_current_depth;	/* only for directory depth */
307 		__le16 i_gc_failures;	/*
308 					 * # of gc failures on pinned file.
309 					 * only for regular files.
310 					 */
311 	};
312 	__le32 i_xattr_nid;		/* nid to save xattr */
313 	__le32 i_flags;			/* file attributes */
314 	__le32 i_pino;			/* parent inode number */
315 	__le32 i_namelen;		/* file name length */
316 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
317 	__u8 i_dir_level;		/* dentry_level for large dir */
318 
319 	struct f2fs_extent i_ext;	/* caching a largest extent */
320 
321 	union {
322 		struct {
323 			__le16 i_extra_isize;	/* extra inode attribute size */
324 			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
325 			__le32 i_projid;	/* project id */
326 			__le32 i_inode_checksum;/* inode meta checksum */
327 			__le64 i_crtime;	/* creation time */
328 			__le32 i_crtime_nsec;	/* creation time in nano scale */
329 			__le64 i_compr_blocks;	/* # of compressed blocks */
330 			__u8 i_compress_algorithm;	/* compress algorithm */
331 			__u8 i_log_cluster_size;	/* log of cluster size */
332 			__le16 i_compress_flag;		/* compress flag */
333 						/* 0 bit: chksum flag
334 						 * [8,15] bits: compress level
335 						 */
336 			__le32 i_extra_end[0];	/* for attribute size calculation */
337 		} __packed;
338 		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
339 	};
340 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
341 						double_indirect(1) node id */
342 } __packed;
343 
344 struct direct_node {
345 	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
346 } __packed;
347 
348 struct indirect_node {
349 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
350 } __packed;
351 
352 enum {
353 	COLD_BIT_SHIFT = 0,
354 	FSYNC_BIT_SHIFT,
355 	DENT_BIT_SHIFT,
356 	OFFSET_BIT_SHIFT
357 };
358 
359 #define OFFSET_BIT_MASK		GENMASK(OFFSET_BIT_SHIFT - 1, 0)
360 
361 struct f2fs_node {
362 	/* can be one of three types: inode, direct, and indirect types */
363 	union {
364 		struct f2fs_inode i;
365 		struct direct_node dn;
366 		struct indirect_node in;
367 	};
368 	struct node_footer footer;
369 } __packed;
370 
371 /*
372  * For NAT entries
373  */
374 #define NAT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_nat_entry))
375 
376 struct f2fs_nat_entry {
377 	__u8 version;		/* latest version of cached nat entry */
378 	__le32 ino;		/* inode number */
379 	__le32 block_addr;	/* block address */
380 } __packed;
381 
382 struct f2fs_nat_block {
383 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
384 } __packed;
385 
386 /*
387  * For SIT entries
388  *
389  * A validity bitmap of 64 bytes covers 512 blocks of area. For a 4K page size,
390  * this results in a segment size of 2MB. For 16k pages, the default segment size
391  * is 8MB.
392  * Not allow to change this.
393  */
394 #define SIT_VBLOCK_MAP_SIZE 64
395 #define SIT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_sit_entry))
396 
397 /*
398  * F2FS uses 4 bytes to represent block address. As a result, supported size of
399  * disk is 16 TB for a 4K page size and 64 TB for a 16K page size and it equals
400  * to 16 * 1024 * 1024 / 2 segments.
401  */
402 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
403 
404 /*
405  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
406  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
407  * [9:0] : valid block count
408  */
409 #define SIT_VBLOCKS_SHIFT	10
410 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
411 #define GET_SIT_VBLOCKS(raw_sit)				\
412 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
413 #define GET_SIT_TYPE(raw_sit)					\
414 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
415 	 >> SIT_VBLOCKS_SHIFT)
416 
417 struct f2fs_sit_entry {
418 	__le16 vblocks;				/* reference above */
419 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
420 	__le64 mtime;				/* segment age for cleaning */
421 } __packed;
422 
423 struct f2fs_sit_block {
424 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
425 } __packed;
426 
427 /*
428  * For segment summary
429  *
430  * One summary block with 4KB size contains exactly 512 summary entries, which
431  * represents exactly one segment with 2MB size.
432  * Similarly, in the case of block with 16KB size, it represents one segment with 8MB size.
433  * Not allow to change the basic units.
434  *
435  * NOTE: For initializing fields, you must use set_summary
436  *
437  * - If data page, nid represents dnode's nid
438  * - If node page, nid represents the node page's nid.
439  *
440  * The ofs_in_node is used by only data page. It represents offset
441  * from node's page's beginning to get a data block address.
442  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
443  */
444 #define ENTRIES_IN_SUM		(F2FS_BLKSIZE / 8)
445 #define	SUMMARY_SIZE		(7)	/* sizeof(struct f2fs_summary) */
446 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
447 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
448 
449 /* a summary entry for a block in a segment */
450 struct f2fs_summary {
451 	__le32 nid;		/* parent node id */
452 	union {
453 		__u8 reserved[3];
454 		struct {
455 			__u8 version;		/* node version number */
456 			__le16 ofs_in_node;	/* block index in parent node */
457 		} __packed;
458 	};
459 } __packed;
460 
461 /* summary block type, node or data, is stored to the summary_footer */
462 #define SUM_TYPE_NODE		(1)
463 #define SUM_TYPE_DATA		(0)
464 
465 struct summary_footer {
466 	unsigned char entry_type;	/* SUM_TYPE_XXX */
467 	__le32 check_sum;		/* summary checksum */
468 } __packed;
469 
470 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
471 				SUM_ENTRY_SIZE)
472 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
473 				sizeof(struct nat_journal_entry))
474 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
475 				sizeof(struct nat_journal_entry))
476 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
477 				sizeof(struct sit_journal_entry))
478 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
479 				sizeof(struct sit_journal_entry))
480 
481 /* Reserved area should make size of f2fs_extra_info equals to
482  * that of nat_journal and sit_journal.
483  */
484 #define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
485 
486 /*
487  * frequently updated NAT/SIT entries can be stored in the spare area in
488  * summary blocks
489  */
490 enum {
491 	NAT_JOURNAL = 0,
492 	SIT_JOURNAL
493 };
494 
495 struct nat_journal_entry {
496 	__le32 nid;
497 	struct f2fs_nat_entry ne;
498 } __packed;
499 
500 struct nat_journal {
501 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
502 	__u8 reserved[NAT_JOURNAL_RESERVED];
503 } __packed;
504 
505 struct sit_journal_entry {
506 	__le32 segno;
507 	struct f2fs_sit_entry se;
508 } __packed;
509 
510 struct sit_journal {
511 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
512 	__u8 reserved[SIT_JOURNAL_RESERVED];
513 } __packed;
514 
515 struct f2fs_extra_info {
516 	__le64 kbytes_written;
517 	__u8 reserved[EXTRA_INFO_RESERVED];
518 } __packed;
519 
520 struct f2fs_journal {
521 	union {
522 		__le16 n_nats;
523 		__le16 n_sits;
524 	};
525 	/* spare area is used by NAT or SIT journals or extra info */
526 	union {
527 		struct nat_journal nat_j;
528 		struct sit_journal sit_j;
529 		struct f2fs_extra_info info;
530 	};
531 } __packed;
532 
533 /* Block-sized summary block structure */
534 struct f2fs_summary_block {
535 	struct f2fs_summary entries[ENTRIES_IN_SUM];
536 	struct f2fs_journal journal;
537 	struct summary_footer footer;
538 } __packed;
539 
540 /*
541  * For directory operations
542  */
543 #define F2FS_DOT_HASH		0
544 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
545 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
546 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
547 
548 typedef __le32	f2fs_hash_t;
549 
550 /* One directory entry slot covers 8bytes-long file name */
551 #define F2FS_SLOT_LEN		8
552 #define F2FS_SLOT_LEN_BITS	3
553 
554 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
555 
556 /* MAX level for dir lookup */
557 #define MAX_DIR_HASH_DEPTH	63
558 
559 /* MAX buckets in one level of dir */
560 #define MAX_DIR_BUCKETS		BIT((MAX_DIR_HASH_DEPTH / 2) - 1)
561 
562 /*
563  * space utilization of regular dentry and inline dentry (w/o extra reservation)
564  * when block size is 4KB.
565  *		regular dentry		inline dentry (def)	inline dentry (min)
566  * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
567  * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
568  * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
569  * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
570  * total	4096			3488			40
571  *
572  * Note: there are more reserved space in inline dentry than in regular
573  * dentry, when converting inline dentry we should handle this carefully.
574  */
575 
576 /* the number of dentry in a block */
577 #define NR_DENTRY_IN_BLOCK	((BITS_PER_BYTE * F2FS_BLKSIZE) / \
578 					((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * BITS_PER_BYTE + 1))
579 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
580 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
581 					BITS_PER_BYTE)
582 #define SIZE_OF_RESERVED	(F2FS_BLKSIZE - ((SIZE_OF_DIR_ENTRY + \
583 				F2FS_SLOT_LEN) * \
584 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
585 #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
586 
587 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
588 struct f2fs_dir_entry {
589 	__le32 hash_code;	/* hash code of file name */
590 	__le32 ino;		/* inode number */
591 	__le16 name_len;	/* length of file name */
592 	__u8 file_type;		/* file type */
593 } __packed;
594 
595 /* Block-sized directory entry block */
596 struct f2fs_dentry_block {
597 	/* validity bitmap for directory entries in each block */
598 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
599 	__u8 reserved[SIZE_OF_RESERVED];
600 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
601 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
602 } __packed;
603 
604 #define	F2FS_DEF_PROJID		0	/* default project ID */
605 
606 #endif  /* _LINUX_F2FS_FS_H */
607