xref: /linux/include/linux/f2fs_fs.h (revision 957e3facd147510f2cf8780e38606f1d707f0e33)
1 /**
2  * include/linux/f2fs_fs.h
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #ifndef _LINUX_F2FS_FS_H
12 #define _LINUX_F2FS_FS_H
13 
14 #include <linux/pagemap.h>
15 #include <linux/types.h>
16 
17 #define F2FS_SUPER_OFFSET		1024	/* byte-size offset */
18 #define F2FS_MIN_LOG_SECTOR_SIZE	9	/* 9 bits for 512 bytes */
19 #define F2FS_MAX_LOG_SECTOR_SIZE	12	/* 12 bits for 4096 bytes */
20 #define F2FS_LOG_SECTORS_PER_BLOCK	3	/* log number for sector/blk */
21 #define F2FS_BLKSIZE			4096	/* support only 4KB block */
22 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
23 #define F2FS_BLK_ALIGN(x)	(((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
24 
25 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
26 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
27 
28 /* 0, 1(node nid), 2(meta nid) are reserved node id */
29 #define F2FS_RESERVED_NODE_NUM		3
30 
31 #define F2FS_ROOT_INO(sbi)	(sbi->root_ino_num)
32 #define F2FS_NODE_INO(sbi)	(sbi->node_ino_num)
33 #define F2FS_META_INO(sbi)	(sbi->meta_ino_num)
34 
35 /* This flag is used by node and meta inodes, and by recovery */
36 #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
37 #define GFP_F2FS_HIGH_ZERO	(GFP_NOFS | __GFP_ZERO | __GFP_HIGHMEM)
38 
39 /*
40  * For further optimization on multi-head logs, on-disk layout supports maximum
41  * 16 logs by default. The number, 16, is expected to cover all the cases
42  * enoughly. The implementaion currently uses no more than 6 logs.
43  * Half the logs are used for nodes, and the other half are used for data.
44  */
45 #define MAX_ACTIVE_LOGS	16
46 #define MAX_ACTIVE_NODE_LOGS	8
47 #define MAX_ACTIVE_DATA_LOGS	8
48 
49 /*
50  * For superblock
51  */
52 struct f2fs_super_block {
53 	__le32 magic;			/* Magic Number */
54 	__le16 major_ver;		/* Major Version */
55 	__le16 minor_ver;		/* Minor Version */
56 	__le32 log_sectorsize;		/* log2 sector size in bytes */
57 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
58 	__le32 log_blocksize;		/* log2 block size in bytes */
59 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
60 	__le32 segs_per_sec;		/* # of segments per section */
61 	__le32 secs_per_zone;		/* # of sections per zone */
62 	__le32 checksum_offset;		/* checksum offset inside super block */
63 	__le64 block_count;		/* total # of user blocks */
64 	__le32 section_count;		/* total # of sections */
65 	__le32 segment_count;		/* total # of segments */
66 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
67 	__le32 segment_count_sit;	/* # of segments for SIT */
68 	__le32 segment_count_nat;	/* # of segments for NAT */
69 	__le32 segment_count_ssa;	/* # of segments for SSA */
70 	__le32 segment_count_main;	/* # of segments for main area */
71 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
72 	__le32 cp_blkaddr;		/* start block address of checkpoint */
73 	__le32 sit_blkaddr;		/* start block address of SIT */
74 	__le32 nat_blkaddr;		/* start block address of NAT */
75 	__le32 ssa_blkaddr;		/* start block address of SSA */
76 	__le32 main_blkaddr;		/* start block address of main area */
77 	__le32 root_ino;		/* root inode number */
78 	__le32 node_ino;		/* node inode number */
79 	__le32 meta_ino;		/* meta inode number */
80 	__u8 uuid[16];			/* 128-bit uuid for volume */
81 	__le16 volume_name[512];	/* volume name */
82 	__le32 extension_count;		/* # of extensions below */
83 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
84 	__le32 cp_payload;
85 } __packed;
86 
87 /*
88  * For checkpoint
89  */
90 #define CP_FSCK_FLAG		0x00000010
91 #define CP_ERROR_FLAG		0x00000008
92 #define CP_COMPACT_SUM_FLAG	0x00000004
93 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
94 #define CP_UMOUNT_FLAG		0x00000001
95 
96 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
97 
98 struct f2fs_checkpoint {
99 	__le64 checkpoint_ver;		/* checkpoint block version number */
100 	__le64 user_block_count;	/* # of user blocks */
101 	__le64 valid_block_count;	/* # of valid blocks in main area */
102 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
103 	__le32 overprov_segment_count;	/* # of overprovision segments */
104 	__le32 free_segment_count;	/* # of free segments in main area */
105 
106 	/* information of current node segments */
107 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
108 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
109 	/* information of current data segments */
110 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
111 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
112 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
113 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
114 	__le32 cp_pack_start_sum;	/* start block number of data summary */
115 	__le32 valid_node_count;	/* Total number of valid nodes */
116 	__le32 valid_inode_count;	/* Total number of valid inodes */
117 	__le32 next_free_nid;		/* Next free node number */
118 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
119 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
120 	__le32 checksum_offset;		/* checksum offset inside cp block */
121 	__le64 elapsed_time;		/* mounted time */
122 	/* allocation type of current segment */
123 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
124 
125 	/* SIT and NAT version bitmap */
126 	unsigned char sit_nat_version_bitmap[1];
127 } __packed;
128 
129 /*
130  * For orphan inode management
131  */
132 #define F2FS_ORPHANS_PER_BLOCK	1020
133 
134 #define GET_ORPHAN_BLOCKS(n)	((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
135 					F2FS_ORPHANS_PER_BLOCK)
136 
137 struct f2fs_orphan_block {
138 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
139 	__le32 reserved;	/* reserved */
140 	__le16 blk_addr;	/* block index in current CP */
141 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
142 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
143 	__le32 check_sum;	/* CRC32 for orphan inode block */
144 } __packed;
145 
146 /*
147  * For NODE structure
148  */
149 struct f2fs_extent {
150 	__le32 fofs;		/* start file offset of the extent */
151 	__le32 blk_addr;	/* start block address of the extent */
152 	__le32 len;		/* lengh of the extent */
153 } __packed;
154 
155 #define F2FS_NAME_LEN		255
156 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
157 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
158 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
159 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
160 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
161 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
162 
163 #define ADDRS_PER_PAGE(page, fi)	\
164 	(IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
165 
166 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
167 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
168 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
169 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
170 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
171 
172 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
173 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
174 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
175 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
176 
177 #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
178 						F2FS_INLINE_XATTR_ADDRS - 1))
179 
180 struct f2fs_inode {
181 	__le16 i_mode;			/* file mode */
182 	__u8 i_advise;			/* file hints */
183 	__u8 i_inline;			/* file inline flags */
184 	__le32 i_uid;			/* user ID */
185 	__le32 i_gid;			/* group ID */
186 	__le32 i_links;			/* links count */
187 	__le64 i_size;			/* file size in bytes */
188 	__le64 i_blocks;		/* file size in blocks */
189 	__le64 i_atime;			/* access time */
190 	__le64 i_ctime;			/* change time */
191 	__le64 i_mtime;			/* modification time */
192 	__le32 i_atime_nsec;		/* access time in nano scale */
193 	__le32 i_ctime_nsec;		/* change time in nano scale */
194 	__le32 i_mtime_nsec;		/* modification time in nano scale */
195 	__le32 i_generation;		/* file version (for NFS) */
196 	__le32 i_current_depth;		/* only for directory depth */
197 	__le32 i_xattr_nid;		/* nid to save xattr */
198 	__le32 i_flags;			/* file attributes */
199 	__le32 i_pino;			/* parent inode number */
200 	__le32 i_namelen;		/* file name length */
201 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
202 	__u8 i_dir_level;		/* dentry_level for large dir */
203 
204 	struct f2fs_extent i_ext;	/* caching a largest extent */
205 
206 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
207 
208 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
209 						double_indirect(1) node id */
210 } __packed;
211 
212 struct direct_node {
213 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
214 } __packed;
215 
216 struct indirect_node {
217 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
218 } __packed;
219 
220 enum {
221 	COLD_BIT_SHIFT = 0,
222 	FSYNC_BIT_SHIFT,
223 	DENT_BIT_SHIFT,
224 	OFFSET_BIT_SHIFT
225 };
226 
227 struct node_footer {
228 	__le32 nid;		/* node id */
229 	__le32 ino;		/* inode nunmber */
230 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
231 	__le64 cp_ver;		/* checkpoint version */
232 	__le32 next_blkaddr;	/* next node page block address */
233 } __packed;
234 
235 struct f2fs_node {
236 	/* can be one of three types: inode, direct, and indirect types */
237 	union {
238 		struct f2fs_inode i;
239 		struct direct_node dn;
240 		struct indirect_node in;
241 	};
242 	struct node_footer footer;
243 } __packed;
244 
245 /*
246  * For NAT entries
247  */
248 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
249 
250 struct f2fs_nat_entry {
251 	__u8 version;		/* latest version of cached nat entry */
252 	__le32 ino;		/* inode number */
253 	__le32 block_addr;	/* block address */
254 } __packed;
255 
256 struct f2fs_nat_block {
257 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
258 } __packed;
259 
260 /*
261  * For SIT entries
262  *
263  * Each segment is 2MB in size by default so that a bitmap for validity of
264  * there-in blocks should occupy 64 bytes, 512 bits.
265  * Not allow to change this.
266  */
267 #define SIT_VBLOCK_MAP_SIZE 64
268 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
269 
270 /*
271  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
272  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
273  * [9:0] : valid block count
274  */
275 #define SIT_VBLOCKS_SHIFT	10
276 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
277 #define GET_SIT_VBLOCKS(raw_sit)				\
278 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
279 #define GET_SIT_TYPE(raw_sit)					\
280 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
281 	 >> SIT_VBLOCKS_SHIFT)
282 
283 struct f2fs_sit_entry {
284 	__le16 vblocks;				/* reference above */
285 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
286 	__le64 mtime;				/* segment age for cleaning */
287 } __packed;
288 
289 struct f2fs_sit_block {
290 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
291 } __packed;
292 
293 /*
294  * For segment summary
295  *
296  * One summary block contains exactly 512 summary entries, which represents
297  * exactly 2MB segment by default. Not allow to change the basic units.
298  *
299  * NOTE: For initializing fields, you must use set_summary
300  *
301  * - If data page, nid represents dnode's nid
302  * - If node page, nid represents the node page's nid.
303  *
304  * The ofs_in_node is used by only data page. It represents offset
305  * from node's page's beginning to get a data block address.
306  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
307  */
308 #define ENTRIES_IN_SUM		512
309 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
310 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
311 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
312 
313 /* a summary entry for a 4KB-sized block in a segment */
314 struct f2fs_summary {
315 	__le32 nid;		/* parent node id */
316 	union {
317 		__u8 reserved[3];
318 		struct {
319 			__u8 version;		/* node version number */
320 			__le16 ofs_in_node;	/* block index in parent node */
321 		} __packed;
322 	};
323 } __packed;
324 
325 /* summary block type, node or data, is stored to the summary_footer */
326 #define SUM_TYPE_NODE		(1)
327 #define SUM_TYPE_DATA		(0)
328 
329 struct summary_footer {
330 	unsigned char entry_type;	/* SUM_TYPE_XXX */
331 	__u32 check_sum;		/* summary checksum */
332 } __packed;
333 
334 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
335 				SUM_ENTRY_SIZE)
336 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
337 				sizeof(struct nat_journal_entry))
338 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
339 				sizeof(struct nat_journal_entry))
340 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
341 				sizeof(struct sit_journal_entry))
342 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
343 				sizeof(struct sit_journal_entry))
344 /*
345  * frequently updated NAT/SIT entries can be stored in the spare area in
346  * summary blocks
347  */
348 enum {
349 	NAT_JOURNAL = 0,
350 	SIT_JOURNAL
351 };
352 
353 struct nat_journal_entry {
354 	__le32 nid;
355 	struct f2fs_nat_entry ne;
356 } __packed;
357 
358 struct nat_journal {
359 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
360 	__u8 reserved[NAT_JOURNAL_RESERVED];
361 } __packed;
362 
363 struct sit_journal_entry {
364 	__le32 segno;
365 	struct f2fs_sit_entry se;
366 } __packed;
367 
368 struct sit_journal {
369 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
370 	__u8 reserved[SIT_JOURNAL_RESERVED];
371 } __packed;
372 
373 /* 4KB-sized summary block structure */
374 struct f2fs_summary_block {
375 	struct f2fs_summary entries[ENTRIES_IN_SUM];
376 	union {
377 		__le16 n_nats;
378 		__le16 n_sits;
379 	};
380 	/* spare area is used by NAT or SIT journals */
381 	union {
382 		struct nat_journal nat_j;
383 		struct sit_journal sit_j;
384 	};
385 	struct summary_footer footer;
386 } __packed;
387 
388 /*
389  * For directory operations
390  */
391 #define F2FS_DOT_HASH		0
392 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
393 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
394 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
395 
396 typedef __le32	f2fs_hash_t;
397 
398 /* One directory entry slot covers 8bytes-long file name */
399 #define F2FS_SLOT_LEN		8
400 #define F2FS_SLOT_LEN_BITS	3
401 
402 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
403 
404 /* the number of dentry in a block */
405 #define NR_DENTRY_IN_BLOCK	214
406 
407 /* MAX level for dir lookup */
408 #define MAX_DIR_HASH_DEPTH	63
409 
410 /* MAX buckets in one level of dir */
411 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
412 
413 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
414 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
415 					BITS_PER_BYTE)
416 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
417 				F2FS_SLOT_LEN) * \
418 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
419 
420 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
421 struct f2fs_dir_entry {
422 	__le32 hash_code;	/* hash code of file name */
423 	__le32 ino;		/* inode number */
424 	__le16 name_len;	/* lengh of file name */
425 	__u8 file_type;		/* file type */
426 } __packed;
427 
428 /* 4KB-sized directory entry block */
429 struct f2fs_dentry_block {
430 	/* validity bitmap for directory entries in each block */
431 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
432 	__u8 reserved[SIZE_OF_RESERVED];
433 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
434 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
435 } __packed;
436 
437 /* for inline dir */
438 #define NR_INLINE_DENTRY	(MAX_INLINE_DATA * BITS_PER_BYTE / \
439 				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
440 				BITS_PER_BYTE + 1))
441 #define INLINE_DENTRY_BITMAP_SIZE	((NR_INLINE_DENTRY + \
442 					BITS_PER_BYTE - 1) / BITS_PER_BYTE)
443 #define INLINE_RESERVED_SIZE	(MAX_INLINE_DATA - \
444 				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
445 				NR_INLINE_DENTRY + INLINE_DENTRY_BITMAP_SIZE))
446 
447 /* inline directory entry structure */
448 struct f2fs_inline_dentry {
449 	__u8 dentry_bitmap[INLINE_DENTRY_BITMAP_SIZE];
450 	__u8 reserved[INLINE_RESERVED_SIZE];
451 	struct f2fs_dir_entry dentry[NR_INLINE_DENTRY];
452 	__u8 filename[NR_INLINE_DENTRY][F2FS_SLOT_LEN];
453 } __packed;
454 
455 /* file types used in inode_info->flags */
456 enum {
457 	F2FS_FT_UNKNOWN,
458 	F2FS_FT_REG_FILE,
459 	F2FS_FT_DIR,
460 	F2FS_FT_CHRDEV,
461 	F2FS_FT_BLKDEV,
462 	F2FS_FT_FIFO,
463 	F2FS_FT_SOCK,
464 	F2FS_FT_SYMLINK,
465 	F2FS_FT_MAX
466 };
467 
468 #endif  /* _LINUX_F2FS_FS_H */
469