xref: /linux/include/linux/f2fs_fs.h (revision d3b7a868f1aeb6a43de880a3709ef3a0341f2c2a)
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_READ_META,
84 	STOP_CP_REASON_READ_NODE,
85 	STOP_CP_REASON_READ_DATA,
86 	STOP_CP_REASON_MAX,
87 };
88 
89 #define	MAX_STOP_REASON			32
90 
91 /* detail reason for EFSCORRUPTED */
92 enum f2fs_error {
93 	ERROR_CORRUPTED_CLUSTER,
94 	ERROR_FAIL_DECOMPRESSION,
95 	ERROR_INVALID_BLKADDR,
96 	ERROR_CORRUPTED_DIRENT,
97 	ERROR_CORRUPTED_INODE,
98 	ERROR_INCONSISTENT_SUMMARY,
99 	ERROR_INCONSISTENT_FOOTER,
100 	ERROR_INCONSISTENT_SUM_TYPE,
101 	ERROR_CORRUPTED_JOURNAL,
102 	ERROR_INCONSISTENT_NODE_COUNT,
103 	ERROR_INCONSISTENT_BLOCK_COUNT,
104 	ERROR_INVALID_CURSEG,
105 	ERROR_INCONSISTENT_SIT,
106 	ERROR_CORRUPTED_VERITY_XATTR,
107 	ERROR_CORRUPTED_XATTR,
108 	ERROR_INVALID_NODE_REFERENCE,
109 	ERROR_INCONSISTENT_NAT,
110 	ERROR_MAX,
111 };
112 
113 #define MAX_F2FS_ERRORS			16
114 
115 struct f2fs_super_block {
116 	__le32 magic;			/* Magic Number */
117 	__le16 major_ver;		/* Major Version */
118 	__le16 minor_ver;		/* Minor Version */
119 	__le32 log_sectorsize;		/* log2 sector size in bytes */
120 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
121 	__le32 log_blocksize;		/* log2 block size in bytes */
122 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
123 	__le32 segs_per_sec;		/* # of segments per section */
124 	__le32 secs_per_zone;		/* # of sections per zone */
125 	__le32 checksum_offset;		/* checksum offset inside super block */
126 	__le64 block_count;		/* total # of user blocks */
127 	__le32 section_count;		/* total # of sections */
128 	__le32 segment_count;		/* total # of segments */
129 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
130 	__le32 segment_count_sit;	/* # of segments for SIT */
131 	__le32 segment_count_nat;	/* # of segments for NAT */
132 	__le32 segment_count_ssa;	/* # of segments for SSA */
133 	__le32 segment_count_main;	/* # of segments for main area */
134 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
135 	__le32 cp_blkaddr;		/* start block address of checkpoint */
136 	__le32 sit_blkaddr;		/* start block address of SIT */
137 	__le32 nat_blkaddr;		/* start block address of NAT */
138 	__le32 ssa_blkaddr;		/* start block address of SSA */
139 	__le32 main_blkaddr;		/* start block address of main area */
140 	__le32 root_ino;		/* root inode number */
141 	__le32 node_ino;		/* node inode number */
142 	__le32 meta_ino;		/* meta inode number */
143 	__u8 uuid[16];			/* 128-bit uuid for volume */
144 	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
145 	__le32 extension_count;		/* # of extensions below */
146 	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
147 	__le32 cp_payload;
148 	__u8 version[VERSION_LEN];	/* the kernel version */
149 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
150 	__le32 feature;			/* defined features */
151 	__u8 encryption_level;		/* versioning level for encryption */
152 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
153 	struct f2fs_device devs[MAX_DEVICES];	/* device list */
154 	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
155 	__u8 hot_ext_count;		/* # of hot file extension */
156 	__le16  s_encoding;		/* Filename charset encoding */
157 	__le16  s_encoding_flags;	/* Filename charset encoding flags */
158 	__u8 s_stop_reason[MAX_STOP_REASON];	/* stop checkpoint reason */
159 	__u8 s_errors[MAX_F2FS_ERRORS];		/* reason of image corrupts */
160 	__u8 reserved[258];		/* valid reserved region */
161 	__le32 crc;			/* checksum of superblock */
162 } __packed;
163 
164 /*
165  * For checkpoint
166  */
167 #define CP_RESIZEFS_FLAG		0x00004000
168 #define CP_DISABLED_QUICK_FLAG		0x00002000
169 #define CP_DISABLED_FLAG		0x00001000
170 #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
171 #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
172 #define CP_NOCRC_RECOVERY_FLAG	0x00000200
173 #define CP_TRIMMED_FLAG		0x00000100
174 #define CP_NAT_BITS_FLAG	0x00000080
175 #define CP_CRC_RECOVERY_FLAG	0x00000040
176 #define CP_FASTBOOT_FLAG	0x00000020
177 #define CP_FSCK_FLAG		0x00000010
178 #define CP_ERROR_FLAG		0x00000008
179 #define CP_COMPACT_SUM_FLAG	0x00000004
180 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
181 #define CP_UMOUNT_FLAG		0x00000001
182 
183 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
184 
185 struct f2fs_checkpoint {
186 	__le64 checkpoint_ver;		/* checkpoint block version number */
187 	__le64 user_block_count;	/* # of user blocks */
188 	__le64 valid_block_count;	/* # of valid blocks in main area */
189 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
190 	__le32 overprov_segment_count;	/* # of overprovision segments */
191 	__le32 free_segment_count;	/* # of free segments in main area */
192 
193 	/* information of current node segments */
194 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
195 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
196 	/* information of current data segments */
197 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
198 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
199 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
200 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
201 	__le32 cp_pack_start_sum;	/* start block number of data summary */
202 	__le32 valid_node_count;	/* Total number of valid nodes */
203 	__le32 valid_inode_count;	/* Total number of valid inodes */
204 	__le32 next_free_nid;		/* Next free node number */
205 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
206 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
207 	__le32 checksum_offset;		/* checksum offset inside cp block */
208 	__le64 elapsed_time;		/* mounted time */
209 	/* allocation type of current segment */
210 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
211 
212 	/* SIT and NAT version bitmap */
213 	unsigned char sit_nat_version_bitmap[];
214 } __packed;
215 
216 #define CP_CHKSUM_OFFSET	(F2FS_BLKSIZE - sizeof(__le32))	/* default chksum offset in checkpoint */
217 #define CP_MIN_CHKSUM_OFFSET						\
218 	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
219 
220 /*
221  * For orphan inode management
222  */
223 #define F2FS_ORPHANS_PER_BLOCK	((F2FS_BLKSIZE - 4 * sizeof(__le32)) / sizeof(__le32))
224 
225 #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
226 					F2FS_ORPHANS_PER_BLOCK)
227 
228 struct f2fs_orphan_block {
229 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
230 	__le32 reserved;	/* reserved */
231 	__le16 blk_addr;	/* block index in current CP */
232 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
233 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
234 	__le32 check_sum;	/* CRC32 for orphan inode block */
235 } __packed;
236 
237 /*
238  * For NODE structure
239  */
240 struct f2fs_extent {
241 	__le32 fofs;		/* start file offset of the extent */
242 	__le32 blk;		/* start block address of the extent */
243 	__le32 len;		/* length of the extent */
244 } __packed;
245 
246 #define F2FS_NAME_LEN		255
247 /* 200 bytes for inline xattrs by default */
248 #define DEFAULT_INLINE_XATTR_ADDRS	50
249 
250 #define OFFSET_OF_END_OF_I_EXT		360
251 #define SIZE_OF_I_NID			20
252 
253 struct node_footer {
254 	__le32 nid;		/* node id */
255 	__le32 ino;		/* inode number */
256 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
257 	__le64 cp_ver;		/* checkpoint version */
258 	__le32 next_blkaddr;	/* next node page block address */
259 } __packed;
260 
261 /* Address Pointers in an Inode */
262 #define DEF_ADDRS_PER_INODE	((F2FS_BLKSIZE - OFFSET_OF_END_OF_I_EXT	\
263 					- SIZE_OF_I_NID	\
264 					- sizeof(struct node_footer)) / sizeof(__le32))
265 #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
266 					get_extra_isize(inode))
267 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
268 #define ADDRS_PER_INODE(inode)	addrs_per_page(inode, true)
269 /* Address Pointers in a Direct Block */
270 #define DEF_ADDRS_PER_BLOCK	((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
271 #define ADDRS_PER_BLOCK(inode)	addrs_per_page(inode, false)
272 /* Node IDs in an Indirect Block */
273 #define NIDS_PER_BLOCK		((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
274 
275 #define ADDRS_PER_PAGE(folio, inode)	(addrs_per_page(inode, IS_INODE(folio)))
276 
277 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
278 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
279 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
280 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
281 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
282 
283 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
284 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
285 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
286 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
287 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries (obsolete) */
288 #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
289 #define F2FS_PIN_FILE		0x40	/* file should not be gced */
290 #define F2FS_COMPRESS_RELEASED	0x80	/* file released compressed blocks */
291 
292 struct f2fs_inode {
293 	__le16 i_mode;			/* file mode */
294 	__u8 i_advise;			/* file hints */
295 	__u8 i_inline;			/* file inline flags */
296 	__le32 i_uid;			/* user ID */
297 	__le32 i_gid;			/* group ID */
298 	__le32 i_links;			/* links count */
299 	__le64 i_size;			/* file size in bytes */
300 	__le64 i_blocks;		/* file size in blocks */
301 	__le64 i_atime;			/* access time */
302 	__le64 i_ctime;			/* change time */
303 	__le64 i_mtime;			/* modification time */
304 	__le32 i_atime_nsec;		/* access time in nano scale */
305 	__le32 i_ctime_nsec;		/* change time in nano scale */
306 	__le32 i_mtime_nsec;		/* modification time in nano scale */
307 	__le32 i_generation;		/* file version (for NFS) */
308 	union {
309 		__le32 i_current_depth;	/* only for directory depth */
310 		__le16 i_gc_failures;	/*
311 					 * # of gc failures on pinned file.
312 					 * only for regular files.
313 					 */
314 	};
315 	__le32 i_xattr_nid;		/* nid to save xattr */
316 	__le32 i_flags;			/* file attributes */
317 	__le32 i_pino;			/* parent inode number */
318 	__le32 i_namelen;		/* file name length */
319 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
320 	__u8 i_dir_level;		/* dentry_level for large dir */
321 
322 	struct f2fs_extent i_ext;	/* caching a largest extent */
323 
324 	union {
325 		struct {
326 			__le16 i_extra_isize;	/* extra inode attribute size */
327 			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
328 			__le32 i_projid;	/* project id */
329 			__le32 i_inode_checksum;/* inode meta checksum */
330 			__le64 i_crtime;	/* creation time */
331 			__le32 i_crtime_nsec;	/* creation time in nano scale */
332 			__le64 i_compr_blocks;	/* # of compressed blocks */
333 			__u8 i_compress_algorithm;	/* compress algorithm */
334 			__u8 i_log_cluster_size;	/* log of cluster size */
335 			__le16 i_compress_flag;		/* compress flag */
336 						/* 0 bit: chksum flag
337 						 * [8,15] bits: compress level
338 						 */
339 			__le32 i_extra_end[0];	/* for attribute size calculation */
340 		} __packed;
341 		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
342 	};
343 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
344 						double_indirect(1) node id */
345 } __packed;
346 
347 struct direct_node {
348 	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
349 } __packed;
350 
351 struct indirect_node {
352 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
353 } __packed;
354 
355 enum {
356 	COLD_BIT_SHIFT = 0,
357 	FSYNC_BIT_SHIFT,
358 	DENT_BIT_SHIFT,
359 	OFFSET_BIT_SHIFT
360 };
361 
362 #define OFFSET_BIT_MASK		GENMASK(OFFSET_BIT_SHIFT - 1, 0)
363 
364 struct f2fs_node {
365 	/* can be one of three types: inode, direct, and indirect types */
366 	union {
367 		struct f2fs_inode i;
368 		struct direct_node dn;
369 		struct indirect_node in;
370 	};
371 	struct node_footer footer;
372 } __packed;
373 
374 /*
375  * For NAT entries
376  */
377 #define NAT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_nat_entry))
378 
379 struct f2fs_nat_entry {
380 	__u8 version;		/* latest version of cached nat entry */
381 	__le32 ino;		/* inode number */
382 	__le32 block_addr;	/* block address */
383 } __packed;
384 
385 struct f2fs_nat_block {
386 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
387 } __packed;
388 
389 /*
390  * For SIT entries
391  *
392  * A validity bitmap of 64 bytes covers 512 blocks of area. For a 4K page size,
393  * this results in a segment size of 2MB. For 16k pages, the default segment size
394  * is 8MB.
395  * Not allow to change this.
396  */
397 #define SIT_VBLOCK_MAP_SIZE 64
398 #define SIT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_sit_entry))
399 
400 /*
401  * F2FS uses 4 bytes to represent block address. As a result, supported size of
402  * disk is 16 TB for a 4K page size and 64 TB for a 16K page size and it equals
403  * to 16 * 1024 * 1024 / 2 segments.
404  */
405 #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
406 
407 /*
408  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
409  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
410  * [9:0] : valid block count
411  */
412 #define SIT_VBLOCKS_SHIFT	10
413 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
414 #define GET_SIT_VBLOCKS(raw_sit)				\
415 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
416 #define GET_SIT_TYPE(raw_sit)					\
417 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
418 	 >> SIT_VBLOCKS_SHIFT)
419 
420 struct f2fs_sit_entry {
421 	__le16 vblocks;				/* reference above */
422 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
423 	__le64 mtime;				/* segment age for cleaning */
424 } __packed;
425 
426 struct f2fs_sit_block {
427 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
428 } __packed;
429 
430 /*
431  * For segment summary
432  *
433  * One summary block with 4KB size contains exactly 512 summary entries, which
434  * represents exactly one segment with 2MB size.
435  * Similarly, in the case of block with 16KB size, it represents one segment with 8MB size.
436  * Not allow to change the basic units.
437  *
438  * NOTE: For initializing fields, you must use set_summary
439  *
440  * - If data page, nid represents dnode's nid
441  * - If node page, nid represents the node page's nid.
442  *
443  * The ofs_in_node is used by only data page. It represents offset
444  * from node's page's beginning to get a data block address.
445  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
446  */
447 #define	SUMMARY_SIZE		(7)	/* sizeof(struct f2fs_summary) */
448 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
449 
450 /* a summary entry for a block in a segment */
451 struct f2fs_summary {
452 	__le32 nid;		/* parent node id */
453 	union {
454 		__u8 reserved[3];
455 		struct {
456 			__u8 version;		/* node version number */
457 			__le16 ofs_in_node;	/* block index in parent node */
458 		} __packed;
459 	};
460 } __packed;
461 
462 /* summary block type, node or data, is stored to the summary_footer */
463 #define SUM_TYPE_NODE		(1)
464 #define SUM_TYPE_DATA		(0)
465 
466 struct summary_footer {
467 	unsigned char entry_type;	/* SUM_TYPE_XXX */
468 	__le32 check_sum;		/* summary checksum */
469 } __packed;
470 
471 /*
472  * frequently updated NAT/SIT entries can be stored in the spare area in
473  * summary blocks
474  */
475 enum {
476 	NAT_JOURNAL = 0,
477 	SIT_JOURNAL
478 };
479 
480 struct nat_journal_entry {
481 	__le32 nid;
482 	struct f2fs_nat_entry ne;
483 } __packed;
484 
485 /*
486  * The nat_journal structure is a placeholder whose actual size varies depending
487  * on the use of packed_ssa. Therefore, it must always be accessed only through
488  * specific sets of macros and fields, and size calculations should use
489  * size-related macros instead of sizeof().
490  * Relevant macros: sbi->nat_journal_entries, nat_in_journal(),
491  * nid_in_journal(), MAX_NAT_JENTRIES().
492  */
493 struct nat_journal {
494 	struct nat_journal_entry entries[0];
495 } __packed;
496 
497 struct sit_journal_entry {
498 	__le32 segno;
499 	struct f2fs_sit_entry se;
500 } __packed;
501 
502 /*
503  * The sit_journal structure is a placeholder whose actual size varies depending
504  * on the use of packed_ssa. Therefore, it must always be accessed only through
505  * specific sets of macros and fields, and size calculations should use
506  * size-related macros instead of sizeof().
507  * Relevant macros: sbi->sit_journal_entries, sit_in_journal(),
508  * segno_in_journal(), MAX_SIT_JENTRIES().
509  */
510 struct sit_journal {
511 	struct sit_journal_entry entries[0];
512 } __packed;
513 
514 struct f2fs_extra_info {
515 	__le64 kbytes_written;
516 	__u8 reserved[];
517 } __packed;
518 
519 struct f2fs_journal {
520 	union {
521 		__le16 n_nats;
522 		__le16 n_sits;
523 	};
524 	/* spare area is used by NAT or SIT journals or extra info */
525 	union {
526 		struct nat_journal nat_j;
527 		struct sit_journal sit_j;
528 		struct f2fs_extra_info info;
529 	};
530 } __packed;
531 
532 /*
533  * Block-sized summary block structure
534  *
535  * The f2fs_summary_block structure is a placeholder whose actual size varies
536  * depending on the use of packed_ssa. Therefore, it must always be accessed
537  * only through specific sets of macros and fields, and size calculations should
538  * use size-related macros instead of sizeof().
539  * Relevant macros: sbi->sum_blocksize, sbi->entries_in_sum,
540  * sbi->sum_entry_size, sum_entries(), sum_journal(), sum_footer().
541  *
542  * Summary Block Layout
543  *
544  * +-----------------------+ <--- Block Start
545  * | struct f2fs_summary   |
546  * | entries[0]            |
547  * | ...                   |
548  * | entries[N-1]          |
549  * +-----------------------+
550  * | struct f2fs_journal   |
551  * +-----------------------+
552  * | struct summary_footer |
553  * +-----------------------+ <--- Block End
554  */
555 struct f2fs_summary_block {
556 	struct f2fs_summary entries[0];
557 	// struct f2fs_journal journal;
558 	// struct summary_footer footer;
559 } __packed;
560 
561 /*
562  * For directory operations
563  */
564 #define F2FS_DOT_HASH		0
565 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
566 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
567 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
568 
569 typedef __le32	f2fs_hash_t;
570 
571 /* One directory entry slot covers 8bytes-long file name */
572 #define F2FS_SLOT_LEN		8
573 #define F2FS_SLOT_LEN_BITS	3
574 
575 #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
576 
577 /* MAX level for dir lookup */
578 #define MAX_DIR_HASH_DEPTH	63
579 
580 /* MAX buckets in one level of dir */
581 #define MAX_DIR_BUCKETS		BIT((MAX_DIR_HASH_DEPTH / 2) - 1)
582 
583 /*
584  * space utilization of regular dentry and inline dentry (w/o extra reservation)
585  * when block size is 4KB.
586  *		regular dentry		inline dentry (def)	inline dentry (min)
587  * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
588  * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
589  * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
590  * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
591  * total	4096			3488			40
592  *
593  * Note: there are more reserved space in inline dentry than in regular
594  * dentry, when converting inline dentry we should handle this carefully.
595  */
596 
597 /* the number of dentry in a block */
598 #define NR_DENTRY_IN_BLOCK	((BITS_PER_BYTE * F2FS_BLKSIZE) / \
599 					((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * BITS_PER_BYTE + 1))
600 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
601 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
602 					BITS_PER_BYTE)
603 #define SIZE_OF_RESERVED	(F2FS_BLKSIZE - ((SIZE_OF_DIR_ENTRY + \
604 				F2FS_SLOT_LEN) * \
605 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
606 #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
607 
608 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
609 struct f2fs_dir_entry {
610 	__le32 hash_code;	/* hash code of file name */
611 	__le32 ino;		/* inode number */
612 	__le16 name_len;	/* length of file name */
613 	__u8 file_type;		/* file type */
614 } __packed;
615 
616 /* Block-sized directory entry block */
617 struct f2fs_dentry_block {
618 	/* validity bitmap for directory entries in each block */
619 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
620 	__u8 reserved[SIZE_OF_RESERVED];
621 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
622 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
623 } __packed;
624 
625 #define	F2FS_DEF_PROJID		0	/* default project ID */
626 
627 #endif  /* _LINUX_F2FS_FS_H */
628