xref: /linux/include/linux/f2fs_fs.h (revision bd912c991d2ef079a32558f057b8663bcf1fb6fc)
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)	BIT(F2FS_OPTION(sbi).write_io_size_bits) /* Blocks */
44 #define F2FS_IO_SIZE_KB(sbi)	BIT(F2FS_OPTION(sbi).write_io_size_bits + 2) /* KB */
45 #define F2FS_IO_SIZE_BITS(sbi)	(F2FS_OPTION(sbi).write_io_size_bits) /* power of 2 */
46 #define F2FS_IO_SIZE_MASK(sbi)	(F2FS_IO_SIZE(sbi) - 1)
47 #define F2FS_IO_ALIGNED(sbi)	(F2FS_IO_SIZE(sbi) > 1)
48 
49 /* This flag is used by node and meta inodes, and by recovery */
50 #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
51 
52 /*
53  * For further optimization on multi-head logs, on-disk layout supports maximum
54  * 16 logs by default. The number, 16, is expected to cover all the cases
55  * enoughly. The implementaion currently uses no more than 6 logs.
56  * Half the logs are used for nodes, and the other half are used for data.
57  */
58 #define MAX_ACTIVE_LOGS	16
59 #define MAX_ACTIVE_NODE_LOGS	8
60 #define MAX_ACTIVE_DATA_LOGS	8
61 
62 #define VERSION_LEN	256
63 #define MAX_VOLUME_NAME		512
64 #define MAX_PATH_LEN		64
65 #define MAX_DEVICES		8
66 
67 /*
68  * For superblock
69  */
70 struct f2fs_device {
71 	__u8 path[MAX_PATH_LEN];
72 	__le32 total_segments;
73 } __packed;
74 
75 /* reason of stop_checkpoint */
76 enum stop_cp_reason {
77 	STOP_CP_REASON_SHUTDOWN,
78 	STOP_CP_REASON_FAULT_INJECT,
79 	STOP_CP_REASON_META_PAGE,
80 	STOP_CP_REASON_WRITE_FAIL,
81 	STOP_CP_REASON_CORRUPTED_SUMMARY,
82 	STOP_CP_REASON_UPDATE_INODE,
83 	STOP_CP_REASON_FLUSH_FAIL,
84 	STOP_CP_REASON_MAX,
85 };
86 
87 #define	MAX_STOP_REASON			32
88 
89 /* detail reason for EFSCORRUPTED */
90 enum f2fs_error {
91 	ERROR_CORRUPTED_CLUSTER,
92 	ERROR_FAIL_DECOMPRESSION,
93 	ERROR_INVALID_BLKADDR,
94 	ERROR_CORRUPTED_DIRENT,
95 	ERROR_CORRUPTED_INODE,
96 	ERROR_INCONSISTENT_SUMMARY,
97 	ERROR_INCONSISTENT_FOOTER,
98 	ERROR_INCONSISTENT_SUM_TYPE,
99 	ERROR_CORRUPTED_JOURNAL,
100 	ERROR_INCONSISTENT_NODE_COUNT,
101 	ERROR_INCONSISTENT_BLOCK_COUNT,
102 	ERROR_INVALID_CURSEG,
103 	ERROR_INCONSISTENT_SIT,
104 	ERROR_CORRUPTED_VERITY_XATTR,
105 	ERROR_CORRUPTED_XATTR,
106 	ERROR_MAX,
107 };
108 
109 #define MAX_F2FS_ERRORS			16
110 
111 struct f2fs_super_block {
112 	__le32 magic;			/* Magic Number */
113 	__le16 major_ver;		/* Major Version */
114 	__le16 minor_ver;		/* Minor Version */
115 	__le32 log_sectorsize;		/* log2 sector size in bytes */
116 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
117 	__le32 log_blocksize;		/* log2 block size in bytes */
118 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
119 	__le32 segs_per_sec;		/* # of segments per section */
120 	__le32 secs_per_zone;		/* # of sections per zone */
121 	__le32 checksum_offset;		/* checksum offset inside super block */
122 	__le64 block_count;		/* total # of user blocks */
123 	__le32 section_count;		/* total # of sections */
124 	__le32 segment_count;		/* total # of segments */
125 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
126 	__le32 segment_count_sit;	/* # of segments for SIT */
127 	__le32 segment_count_nat;	/* # of segments for NAT */
128 	__le32 segment_count_ssa;	/* # of segments for SSA */
129 	__le32 segment_count_main;	/* # of segments for main area */
130 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
131 	__le32 cp_blkaddr;		/* start block address of checkpoint */
132 	__le32 sit_blkaddr;		/* start block address of SIT */
133 	__le32 nat_blkaddr;		/* start block address of NAT */
134 	__le32 ssa_blkaddr;		/* start block address of SSA */
135 	__le32 main_blkaddr;		/* start block address of main area */
136 	__le32 root_ino;		/* root inode number */
137 	__le32 node_ino;		/* node inode number */
138 	__le32 meta_ino;		/* meta inode number */
139 	__u8 uuid[16];			/* 128-bit uuid for volume */
140 	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
141 	__le32 extension_count;		/* # of extensions below */
142 	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
143 	__le32 cp_payload;
144 	__u8 version[VERSION_LEN];	/* the kernel version */
145 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
146 	__le32 feature;			/* defined features */
147 	__u8 encryption_level;		/* versioning level for encryption */
148 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
149 	struct f2fs_device devs[MAX_DEVICES];	/* device list */
150 	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
151 	__u8 hot_ext_count;		/* # of hot file extension */
152 	__le16  s_encoding;		/* Filename charset encoding */
153 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
154 	__u8 s_stop_reason[MAX_STOP_REASON];	/* stop checkpoint reason */
155 	__u8 s_errors[MAX_F2FS_ERRORS];		/* reason of image corrupts */
156 	__u8 reserved[258];		/* valid reserved region */
157 	__le32 crc;			/* checksum of superblock */
158 } __packed;
159 
160 /*
161  * For checkpoint
162  */
163 #define CP_RESIZEFS_FLAG		0x00004000
164 #define CP_DISABLED_QUICK_FLAG		0x00002000
165 #define CP_DISABLED_FLAG		0x00001000
166 #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
167 #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
168 #define CP_NOCRC_RECOVERY_FLAG	0x00000200
169 #define CP_TRIMMED_FLAG		0x00000100
170 #define CP_NAT_BITS_FLAG	0x00000080
171 #define CP_CRC_RECOVERY_FLAG	0x00000040
172 #define CP_FASTBOOT_FLAG	0x00000020
173 #define CP_FSCK_FLAG		0x00000010
174 #define CP_ERROR_FLAG		0x00000008
175 #define CP_COMPACT_SUM_FLAG	0x00000004
176 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
177 #define CP_UMOUNT_FLAG		0x00000001
178 
179 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
180 
181 struct f2fs_checkpoint {
182 	__le64 checkpoint_ver;		/* checkpoint block version number */
183 	__le64 user_block_count;	/* # of user blocks */
184 	__le64 valid_block_count;	/* # of valid blocks in main area */
185 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
186 	__le32 overprov_segment_count;	/* # of overprovision segments */
187 	__le32 free_segment_count;	/* # of free segments in main area */
188 
189 	/* information of current node segments */
190 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
191 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
192 	/* information of current data segments */
193 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
194 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
195 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
196 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
197 	__le32 cp_pack_start_sum;	/* start block number of data summary */
198 	__le32 valid_node_count;	/* Total number of valid nodes */
199 	__le32 valid_inode_count;	/* Total number of valid inodes */
200 	__le32 next_free_nid;		/* Next free node number */
201 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
202 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
203 	__le32 checksum_offset;		/* checksum offset inside cp block */
204 	__le64 elapsed_time;		/* mounted time */
205 	/* allocation type of current segment */
206 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
207 
208 	/* SIT and NAT version bitmap */
209 	unsigned char sit_nat_version_bitmap[];
210 } __packed;
211 
212 #define CP_CHKSUM_OFFSET	4092	/* default chksum offset in checkpoint */
213 #define CP_MIN_CHKSUM_OFFSET						\
214 	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
215 
216 /*
217  * For orphan inode management
218  */
219 #define F2FS_ORPHANS_PER_BLOCK	1020
220 
221 #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
222 					F2FS_ORPHANS_PER_BLOCK)
223 
224 struct f2fs_orphan_block {
225 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
226 	__le32 reserved;	/* reserved */
227 	__le16 blk_addr;	/* block index in current CP */
228 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
229 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
230 	__le32 check_sum;	/* CRC32 for orphan inode block */
231 } __packed;
232 
233 /*
234  * For NODE structure
235  */
236 struct f2fs_extent {
237 	__le32 fofs;		/* start file offset of the extent */
238 	__le32 blk;		/* start block address of the extent */
239 	__le32 len;		/* length of the extent */
240 } __packed;
241 
242 #define F2FS_NAME_LEN		255
243 /* 200 bytes for inline xattrs by default */
244 #define DEFAULT_INLINE_XATTR_ADDRS	50
245 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
246 #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
247 					get_extra_isize(inode))
248 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
249 #define ADDRS_PER_INODE(inode)	addrs_per_inode(inode)
250 #define DEF_ADDRS_PER_BLOCK	1018	/* Address Pointers in a Direct Block */
251 #define ADDRS_PER_BLOCK(inode)	addrs_per_block(inode)
252 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
253 
254 #define ADDRS_PER_PAGE(page, inode)	\
255 	(IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
256 
257 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
258 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
259 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
260 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
261 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
262 
263 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
264 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
265 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
266 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
267 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
268 #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
269 #define F2FS_PIN_FILE		0x40	/* file should not be gced */
270 #define F2FS_COMPRESS_RELEASED	0x80	/* file released compressed blocks */
271 
272 struct f2fs_inode {
273 	__le16 i_mode;			/* file mode */
274 	__u8 i_advise;			/* file hints */
275 	__u8 i_inline;			/* file inline flags */
276 	__le32 i_uid;			/* user ID */
277 	__le32 i_gid;			/* group ID */
278 	__le32 i_links;			/* links count */
279 	__le64 i_size;			/* file size in bytes */
280 	__le64 i_blocks;		/* file size in blocks */
281 	__le64 i_atime;			/* access time */
282 	__le64 i_ctime;			/* change time */
283 	__le64 i_mtime;			/* modification time */
284 	__le32 i_atime_nsec;		/* access time in nano scale */
285 	__le32 i_ctime_nsec;		/* change time in nano scale */
286 	__le32 i_mtime_nsec;		/* modification time in nano scale */
287 	__le32 i_generation;		/* file version (for NFS) */
288 	union {
289 		__le32 i_current_depth;	/* only for directory depth */
290 		__le16 i_gc_failures;	/*
291 					 * # of gc failures on pinned file.
292 					 * only for regular files.
293 					 */
294 	};
295 	__le32 i_xattr_nid;		/* nid to save xattr */
296 	__le32 i_flags;			/* file attributes */
297 	__le32 i_pino;			/* parent inode number */
298 	__le32 i_namelen;		/* file name length */
299 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
300 	__u8 i_dir_level;		/* dentry_level for large dir */
301 
302 	struct f2fs_extent i_ext;	/* caching a largest extent */
303 
304 	union {
305 		struct {
306 			__le16 i_extra_isize;	/* extra inode attribute size */
307 			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
308 			__le32 i_projid;	/* project id */
309 			__le32 i_inode_checksum;/* inode meta checksum */
310 			__le64 i_crtime;	/* creation time */
311 			__le32 i_crtime_nsec;	/* creation time in nano scale */
312 			__le64 i_compr_blocks;	/* # of compressed blocks */
313 			__u8 i_compress_algorithm;	/* compress algorithm */
314 			__u8 i_log_cluster_size;	/* log of cluster size */
315 			__le16 i_compress_flag;		/* compress flag */
316 						/* 0 bit: chksum flag
317 						 * [8,15] bits: compress level
318 						 */
319 			__le32 i_extra_end[0];	/* for attribute size calculation */
320 		} __packed;
321 		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
322 	};
323 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
324 						double_indirect(1) node id */
325 } __packed;
326 
327 struct direct_node {
328 	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
329 } __packed;
330 
331 struct indirect_node {
332 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
333 } __packed;
334 
335 enum {
336 	COLD_BIT_SHIFT = 0,
337 	FSYNC_BIT_SHIFT,
338 	DENT_BIT_SHIFT,
339 	OFFSET_BIT_SHIFT
340 };
341 
342 #define OFFSET_BIT_MASK		GENMASK(OFFSET_BIT_SHIFT - 1, 0)
343 
344 struct node_footer {
345 	__le32 nid;		/* node id */
346 	__le32 ino;		/* inode number */
347 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
348 	__le64 cp_ver;		/* checkpoint version */
349 	__le32 next_blkaddr;	/* next node page block address */
350 } __packed;
351 
352 struct f2fs_node {
353 	/* can be one of three types: inode, direct, and indirect types */
354 	union {
355 		struct f2fs_inode i;
356 		struct direct_node dn;
357 		struct indirect_node in;
358 	};
359 	struct node_footer footer;
360 } __packed;
361 
362 /*
363  * For NAT entries
364  */
365 #define NAT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_nat_entry))
366 
367 struct f2fs_nat_entry {
368 	__u8 version;		/* latest version of cached nat entry */
369 	__le32 ino;		/* inode number */
370 	__le32 block_addr;	/* block address */
371 } __packed;
372 
373 struct f2fs_nat_block {
374 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
375 } __packed;
376 
377 /*
378  * For SIT entries
379  *
380  * Each segment is 2MB in size by default so that a bitmap for validity of
381  * there-in blocks should occupy 64 bytes, 512 bits.
382  * Not allow to change this.
383  */
384 #define SIT_VBLOCK_MAP_SIZE 64
385 #define SIT_ENTRY_PER_BLOCK (PAGE_SIZE / sizeof(struct f2fs_sit_entry))
386 
387 /*
388  * F2FS uses 4 bytes to represent block address. As a result, supported size of
389  * disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.
390  */
391 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
392 
393 /*
394  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
395  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
396  * [9:0] : valid block count
397  */
398 #define SIT_VBLOCKS_SHIFT	10
399 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
400 #define GET_SIT_VBLOCKS(raw_sit)				\
401 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
402 #define GET_SIT_TYPE(raw_sit)					\
403 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
404 	 >> SIT_VBLOCKS_SHIFT)
405 
406 struct f2fs_sit_entry {
407 	__le16 vblocks;				/* reference above */
408 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
409 	__le64 mtime;				/* segment age for cleaning */
410 } __packed;
411 
412 struct f2fs_sit_block {
413 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
414 } __packed;
415 
416 /*
417  * For segment summary
418  *
419  * One summary block contains exactly 512 summary entries, which represents
420  * exactly 2MB segment by default. Not allow to change the basic units.
421  *
422  * NOTE: For initializing fields, you must use set_summary
423  *
424  * - If data page, nid represents dnode's nid
425  * - If node page, nid represents the node page's nid.
426  *
427  * The ofs_in_node is used by only data page. It represents offset
428  * from node's page's beginning to get a data block address.
429  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
430  */
431 #define ENTRIES_IN_SUM		512
432 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
433 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
434 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
435 
436 /* a summary entry for a 4KB-sized block in a segment */
437 struct f2fs_summary {
438 	__le32 nid;		/* parent node id */
439 	union {
440 		__u8 reserved[3];
441 		struct {
442 			__u8 version;		/* node version number */
443 			__le16 ofs_in_node;	/* block index in parent node */
444 		} __packed;
445 	};
446 } __packed;
447 
448 /* summary block type, node or data, is stored to the summary_footer */
449 #define SUM_TYPE_NODE		(1)
450 #define SUM_TYPE_DATA		(0)
451 
452 struct summary_footer {
453 	unsigned char entry_type;	/* SUM_TYPE_XXX */
454 	__le32 check_sum;		/* summary checksum */
455 } __packed;
456 
457 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
458 				SUM_ENTRY_SIZE)
459 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
460 				sizeof(struct nat_journal_entry))
461 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
462 				sizeof(struct nat_journal_entry))
463 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
464 				sizeof(struct sit_journal_entry))
465 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
466 				sizeof(struct sit_journal_entry))
467 
468 /* Reserved area should make size of f2fs_extra_info equals to
469  * that of nat_journal and sit_journal.
470  */
471 #define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
472 
473 /*
474  * frequently updated NAT/SIT entries can be stored in the spare area in
475  * summary blocks
476  */
477 enum {
478 	NAT_JOURNAL = 0,
479 	SIT_JOURNAL
480 };
481 
482 struct nat_journal_entry {
483 	__le32 nid;
484 	struct f2fs_nat_entry ne;
485 } __packed;
486 
487 struct nat_journal {
488 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
489 	__u8 reserved[NAT_JOURNAL_RESERVED];
490 } __packed;
491 
492 struct sit_journal_entry {
493 	__le32 segno;
494 	struct f2fs_sit_entry se;
495 } __packed;
496 
497 struct sit_journal {
498 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
499 	__u8 reserved[SIT_JOURNAL_RESERVED];
500 } __packed;
501 
502 struct f2fs_extra_info {
503 	__le64 kbytes_written;
504 	__u8 reserved[EXTRA_INFO_RESERVED];
505 } __packed;
506 
507 struct f2fs_journal {
508 	union {
509 		__le16 n_nats;
510 		__le16 n_sits;
511 	};
512 	/* spare area is used by NAT or SIT journals or extra info */
513 	union {
514 		struct nat_journal nat_j;
515 		struct sit_journal sit_j;
516 		struct f2fs_extra_info info;
517 	};
518 } __packed;
519 
520 /* 4KB-sized summary block structure */
521 struct f2fs_summary_block {
522 	struct f2fs_summary entries[ENTRIES_IN_SUM];
523 	struct f2fs_journal journal;
524 	struct summary_footer footer;
525 } __packed;
526 
527 /*
528  * For directory operations
529  */
530 #define F2FS_DOT_HASH		0
531 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
532 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
533 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
534 
535 typedef __le32	f2fs_hash_t;
536 
537 /* One directory entry slot covers 8bytes-long file name */
538 #define F2FS_SLOT_LEN		8
539 #define F2FS_SLOT_LEN_BITS	3
540 
541 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
542 
543 /* MAX level for dir lookup */
544 #define MAX_DIR_HASH_DEPTH	63
545 
546 /* MAX buckets in one level of dir */
547 #define MAX_DIR_BUCKETS		BIT((MAX_DIR_HASH_DEPTH / 2) - 1)
548 
549 /*
550  * space utilization of regular dentry and inline dentry (w/o extra reservation)
551  *		regular dentry		inline dentry (def)	inline dentry (min)
552  * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
553  * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
554  * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
555  * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
556  * total	4096			3488			40
557  *
558  * Note: there are more reserved space in inline dentry than in regular
559  * dentry, when converting inline dentry we should handle this carefully.
560  */
561 #define NR_DENTRY_IN_BLOCK	214	/* the number of dentry in a block */
562 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
563 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
564 					BITS_PER_BYTE)
565 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
566 				F2FS_SLOT_LEN) * \
567 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
568 #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
569 
570 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
571 struct f2fs_dir_entry {
572 	__le32 hash_code;	/* hash code of file name */
573 	__le32 ino;		/* inode number */
574 	__le16 name_len;	/* length of file name */
575 	__u8 file_type;		/* file type */
576 } __packed;
577 
578 /* 4KB-sized directory entry block */
579 struct f2fs_dentry_block {
580 	/* validity bitmap for directory entries in each block */
581 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
582 	__u8 reserved[SIZE_OF_RESERVED];
583 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
584 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
585 } __packed;
586 
587 #define	F2FS_DEF_PROJID		0	/* default project ID */
588 
589 #endif  /* _LINUX_F2FS_FS_H */
590