xref: /linux/include/linux/f2fs_fs.h (revision 0da85d1e38b4c186d2248f0239b72d465f5b406c)
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_BLKSIZE_BITS		12	/* bits for F2FS_BLKSIZE */
23 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
24 #define F2FS_BLK_ALIGN(x)	(((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
25 
26 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
27 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
28 
29 #define F2FS_BYTES_TO_BLK(bytes)	((bytes) >> F2FS_BLKSIZE_BITS)
30 #define F2FS_BLK_TO_BYTES(blk)		((blk) << F2FS_BLKSIZE_BITS)
31 
32 /* 0, 1(node nid), 2(meta nid) are reserved node id */
33 #define F2FS_RESERVED_NODE_NUM		3
34 
35 #define F2FS_ROOT_INO(sbi)	(sbi->root_ino_num)
36 #define F2FS_NODE_INO(sbi)	(sbi->node_ino_num)
37 #define F2FS_META_INO(sbi)	(sbi->meta_ino_num)
38 
39 /* This flag is used by node and meta inodes, and by recovery */
40 #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
41 #define GFP_F2FS_HIGH_ZERO	(GFP_NOFS | __GFP_ZERO | __GFP_HIGHMEM)
42 
43 /*
44  * For further optimization on multi-head logs, on-disk layout supports maximum
45  * 16 logs by default. The number, 16, is expected to cover all the cases
46  * enoughly. The implementaion currently uses no more than 6 logs.
47  * Half the logs are used for nodes, and the other half are used for data.
48  */
49 #define MAX_ACTIVE_LOGS	16
50 #define MAX_ACTIVE_NODE_LOGS	8
51 #define MAX_ACTIVE_DATA_LOGS	8
52 
53 /*
54  * For superblock
55  */
56 struct f2fs_super_block {
57 	__le32 magic;			/* Magic Number */
58 	__le16 major_ver;		/* Major Version */
59 	__le16 minor_ver;		/* Minor Version */
60 	__le32 log_sectorsize;		/* log2 sector size in bytes */
61 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
62 	__le32 log_blocksize;		/* log2 block size in bytes */
63 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
64 	__le32 segs_per_sec;		/* # of segments per section */
65 	__le32 secs_per_zone;		/* # of sections per zone */
66 	__le32 checksum_offset;		/* checksum offset inside super block */
67 	__le64 block_count;		/* total # of user blocks */
68 	__le32 section_count;		/* total # of sections */
69 	__le32 segment_count;		/* total # of segments */
70 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
71 	__le32 segment_count_sit;	/* # of segments for SIT */
72 	__le32 segment_count_nat;	/* # of segments for NAT */
73 	__le32 segment_count_ssa;	/* # of segments for SSA */
74 	__le32 segment_count_main;	/* # of segments for main area */
75 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
76 	__le32 cp_blkaddr;		/* start block address of checkpoint */
77 	__le32 sit_blkaddr;		/* start block address of SIT */
78 	__le32 nat_blkaddr;		/* start block address of NAT */
79 	__le32 ssa_blkaddr;		/* start block address of SSA */
80 	__le32 main_blkaddr;		/* start block address of main area */
81 	__le32 root_ino;		/* root inode number */
82 	__le32 node_ino;		/* node inode number */
83 	__le32 meta_ino;		/* meta inode number */
84 	__u8 uuid[16];			/* 128-bit uuid for volume */
85 	__le16 volume_name[512];	/* volume name */
86 	__le32 extension_count;		/* # of extensions below */
87 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
88 	__le32 cp_payload;
89 } __packed;
90 
91 /*
92  * For checkpoint
93  */
94 #define CP_FASTBOOT_FLAG	0x00000020
95 #define CP_FSCK_FLAG		0x00000010
96 #define CP_ERROR_FLAG		0x00000008
97 #define CP_COMPACT_SUM_FLAG	0x00000004
98 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
99 #define CP_UMOUNT_FLAG		0x00000001
100 
101 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
102 
103 struct f2fs_checkpoint {
104 	__le64 checkpoint_ver;		/* checkpoint block version number */
105 	__le64 user_block_count;	/* # of user blocks */
106 	__le64 valid_block_count;	/* # of valid blocks in main area */
107 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
108 	__le32 overprov_segment_count;	/* # of overprovision segments */
109 	__le32 free_segment_count;	/* # of free segments in main area */
110 
111 	/* information of current node segments */
112 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
113 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
114 	/* information of current data segments */
115 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
116 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
117 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
118 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
119 	__le32 cp_pack_start_sum;	/* start block number of data summary */
120 	__le32 valid_node_count;	/* Total number of valid nodes */
121 	__le32 valid_inode_count;	/* Total number of valid inodes */
122 	__le32 next_free_nid;		/* Next free node number */
123 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
124 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
125 	__le32 checksum_offset;		/* checksum offset inside cp block */
126 	__le64 elapsed_time;		/* mounted time */
127 	/* allocation type of current segment */
128 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
129 
130 	/* SIT and NAT version bitmap */
131 	unsigned char sit_nat_version_bitmap[1];
132 } __packed;
133 
134 /*
135  * For orphan inode management
136  */
137 #define F2FS_ORPHANS_PER_BLOCK	1020
138 
139 #define GET_ORPHAN_BLOCKS(n)	((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
140 					F2FS_ORPHANS_PER_BLOCK)
141 
142 struct f2fs_orphan_block {
143 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
144 	__le32 reserved;	/* reserved */
145 	__le16 blk_addr;	/* block index in current CP */
146 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
147 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
148 	__le32 check_sum;	/* CRC32 for orphan inode block */
149 } __packed;
150 
151 /*
152  * For NODE structure
153  */
154 struct f2fs_extent {
155 	__le32 fofs;		/* start file offset of the extent */
156 	__le32 blk;		/* start block address of the extent */
157 	__le32 len;		/* lengh of the extent */
158 } __packed;
159 
160 #define F2FS_NAME_LEN		255
161 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
162 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
163 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
164 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
165 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
166 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
167 
168 #define ADDRS_PER_PAGE(page, fi)	\
169 	(IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
170 
171 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
172 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
173 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
174 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
175 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
176 
177 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
178 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
179 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
180 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
181 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
182 
183 #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
184 						F2FS_INLINE_XATTR_ADDRS - 1))
185 
186 struct f2fs_inode {
187 	__le16 i_mode;			/* file mode */
188 	__u8 i_advise;			/* file hints */
189 	__u8 i_inline;			/* file inline flags */
190 	__le32 i_uid;			/* user ID */
191 	__le32 i_gid;			/* group ID */
192 	__le32 i_links;			/* links count */
193 	__le64 i_size;			/* file size in bytes */
194 	__le64 i_blocks;		/* file size in blocks */
195 	__le64 i_atime;			/* access time */
196 	__le64 i_ctime;			/* change time */
197 	__le64 i_mtime;			/* modification time */
198 	__le32 i_atime_nsec;		/* access time in nano scale */
199 	__le32 i_ctime_nsec;		/* change time in nano scale */
200 	__le32 i_mtime_nsec;		/* modification time in nano scale */
201 	__le32 i_generation;		/* file version (for NFS) */
202 	__le32 i_current_depth;		/* only for directory depth */
203 	__le32 i_xattr_nid;		/* nid to save xattr */
204 	__le32 i_flags;			/* file attributes */
205 	__le32 i_pino;			/* parent inode number */
206 	__le32 i_namelen;		/* file name length */
207 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
208 	__u8 i_dir_level;		/* dentry_level for large dir */
209 
210 	struct f2fs_extent i_ext;	/* caching a largest extent */
211 
212 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
213 
214 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
215 						double_indirect(1) node id */
216 } __packed;
217 
218 struct direct_node {
219 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
220 } __packed;
221 
222 struct indirect_node {
223 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
224 } __packed;
225 
226 enum {
227 	COLD_BIT_SHIFT = 0,
228 	FSYNC_BIT_SHIFT,
229 	DENT_BIT_SHIFT,
230 	OFFSET_BIT_SHIFT
231 };
232 
233 #define OFFSET_BIT_MASK		(0x07)	/* (0x01 << OFFSET_BIT_SHIFT) - 1 */
234 
235 struct node_footer {
236 	__le32 nid;		/* node id */
237 	__le32 ino;		/* inode nunmber */
238 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
239 	__le64 cp_ver;		/* checkpoint version */
240 	__le32 next_blkaddr;	/* next node page block address */
241 } __packed;
242 
243 struct f2fs_node {
244 	/* can be one of three types: inode, direct, and indirect types */
245 	union {
246 		struct f2fs_inode i;
247 		struct direct_node dn;
248 		struct indirect_node in;
249 	};
250 	struct node_footer footer;
251 } __packed;
252 
253 /*
254  * For NAT entries
255  */
256 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
257 
258 struct f2fs_nat_entry {
259 	__u8 version;		/* latest version of cached nat entry */
260 	__le32 ino;		/* inode number */
261 	__le32 block_addr;	/* block address */
262 } __packed;
263 
264 struct f2fs_nat_block {
265 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
266 } __packed;
267 
268 /*
269  * For SIT entries
270  *
271  * Each segment is 2MB in size by default so that a bitmap for validity of
272  * there-in blocks should occupy 64 bytes, 512 bits.
273  * Not allow to change this.
274  */
275 #define SIT_VBLOCK_MAP_SIZE 64
276 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
277 
278 /*
279  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
280  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
281  * [9:0] : valid block count
282  */
283 #define SIT_VBLOCKS_SHIFT	10
284 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
285 #define GET_SIT_VBLOCKS(raw_sit)				\
286 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
287 #define GET_SIT_TYPE(raw_sit)					\
288 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
289 	 >> SIT_VBLOCKS_SHIFT)
290 
291 struct f2fs_sit_entry {
292 	__le16 vblocks;				/* reference above */
293 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
294 	__le64 mtime;				/* segment age for cleaning */
295 } __packed;
296 
297 struct f2fs_sit_block {
298 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
299 } __packed;
300 
301 /*
302  * For segment summary
303  *
304  * One summary block contains exactly 512 summary entries, which represents
305  * exactly 2MB segment by default. Not allow to change the basic units.
306  *
307  * NOTE: For initializing fields, you must use set_summary
308  *
309  * - If data page, nid represents dnode's nid
310  * - If node page, nid represents the node page's nid.
311  *
312  * The ofs_in_node is used by only data page. It represents offset
313  * from node's page's beginning to get a data block address.
314  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
315  */
316 #define ENTRIES_IN_SUM		512
317 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
318 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
319 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
320 
321 /* a summary entry for a 4KB-sized block in a segment */
322 struct f2fs_summary {
323 	__le32 nid;		/* parent node id */
324 	union {
325 		__u8 reserved[3];
326 		struct {
327 			__u8 version;		/* node version number */
328 			__le16 ofs_in_node;	/* block index in parent node */
329 		} __packed;
330 	};
331 } __packed;
332 
333 /* summary block type, node or data, is stored to the summary_footer */
334 #define SUM_TYPE_NODE		(1)
335 #define SUM_TYPE_DATA		(0)
336 
337 struct summary_footer {
338 	unsigned char entry_type;	/* SUM_TYPE_XXX */
339 	__u32 check_sum;		/* summary checksum */
340 } __packed;
341 
342 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
343 				SUM_ENTRY_SIZE)
344 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
345 				sizeof(struct nat_journal_entry))
346 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
347 				sizeof(struct nat_journal_entry))
348 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
349 				sizeof(struct sit_journal_entry))
350 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
351 				sizeof(struct sit_journal_entry))
352 /*
353  * frequently updated NAT/SIT entries can be stored in the spare area in
354  * summary blocks
355  */
356 enum {
357 	NAT_JOURNAL = 0,
358 	SIT_JOURNAL
359 };
360 
361 struct nat_journal_entry {
362 	__le32 nid;
363 	struct f2fs_nat_entry ne;
364 } __packed;
365 
366 struct nat_journal {
367 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
368 	__u8 reserved[NAT_JOURNAL_RESERVED];
369 } __packed;
370 
371 struct sit_journal_entry {
372 	__le32 segno;
373 	struct f2fs_sit_entry se;
374 } __packed;
375 
376 struct sit_journal {
377 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
378 	__u8 reserved[SIT_JOURNAL_RESERVED];
379 } __packed;
380 
381 /* 4KB-sized summary block structure */
382 struct f2fs_summary_block {
383 	struct f2fs_summary entries[ENTRIES_IN_SUM];
384 	union {
385 		__le16 n_nats;
386 		__le16 n_sits;
387 	};
388 	/* spare area is used by NAT or SIT journals */
389 	union {
390 		struct nat_journal nat_j;
391 		struct sit_journal sit_j;
392 	};
393 	struct summary_footer footer;
394 } __packed;
395 
396 /*
397  * For directory operations
398  */
399 #define F2FS_DOT_HASH		0
400 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
401 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
402 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
403 
404 typedef __le32	f2fs_hash_t;
405 
406 /* One directory entry slot covers 8bytes-long file name */
407 #define F2FS_SLOT_LEN		8
408 #define F2FS_SLOT_LEN_BITS	3
409 
410 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
411 
412 /* the number of dentry in a block */
413 #define NR_DENTRY_IN_BLOCK	214
414 
415 /* MAX level for dir lookup */
416 #define MAX_DIR_HASH_DEPTH	63
417 
418 /* MAX buckets in one level of dir */
419 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
420 
421 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
422 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
423 					BITS_PER_BYTE)
424 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
425 				F2FS_SLOT_LEN) * \
426 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
427 
428 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
429 struct f2fs_dir_entry {
430 	__le32 hash_code;	/* hash code of file name */
431 	__le32 ino;		/* inode number */
432 	__le16 name_len;	/* lengh of file name */
433 	__u8 file_type;		/* file type */
434 } __packed;
435 
436 /* 4KB-sized directory entry block */
437 struct f2fs_dentry_block {
438 	/* validity bitmap for directory entries in each block */
439 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
440 	__u8 reserved[SIZE_OF_RESERVED];
441 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
442 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
443 } __packed;
444 
445 /* for inline dir */
446 #define NR_INLINE_DENTRY	(MAX_INLINE_DATA * BITS_PER_BYTE / \
447 				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
448 				BITS_PER_BYTE + 1))
449 #define INLINE_DENTRY_BITMAP_SIZE	((NR_INLINE_DENTRY + \
450 					BITS_PER_BYTE - 1) / BITS_PER_BYTE)
451 #define INLINE_RESERVED_SIZE	(MAX_INLINE_DATA - \
452 				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
453 				NR_INLINE_DENTRY + INLINE_DENTRY_BITMAP_SIZE))
454 
455 /* inline directory entry structure */
456 struct f2fs_inline_dentry {
457 	__u8 dentry_bitmap[INLINE_DENTRY_BITMAP_SIZE];
458 	__u8 reserved[INLINE_RESERVED_SIZE];
459 	struct f2fs_dir_entry dentry[NR_INLINE_DENTRY];
460 	__u8 filename[NR_INLINE_DENTRY][F2FS_SLOT_LEN];
461 } __packed;
462 
463 /* file types used in inode_info->flags */
464 enum {
465 	F2FS_FT_UNKNOWN,
466 	F2FS_FT_REG_FILE,
467 	F2FS_FT_DIR,
468 	F2FS_FT_CHRDEV,
469 	F2FS_FT_BLKDEV,
470 	F2FS_FT_FIFO,
471 	F2FS_FT_SOCK,
472 	F2FS_FT_SYMLINK,
473 	F2FS_FT_MAX
474 };
475 
476 #endif  /* _LINUX_F2FS_FS_H */
477