xref: /linux/include/linux/f2fs_fs.h (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
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 #define VERSION_LEN	256
54 
55 /*
56  * For superblock
57  */
58 struct f2fs_super_block {
59 	__le32 magic;			/* Magic Number */
60 	__le16 major_ver;		/* Major Version */
61 	__le16 minor_ver;		/* Minor Version */
62 	__le32 log_sectorsize;		/* log2 sector size in bytes */
63 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
64 	__le32 log_blocksize;		/* log2 block size in bytes */
65 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
66 	__le32 segs_per_sec;		/* # of segments per section */
67 	__le32 secs_per_zone;		/* # of sections per zone */
68 	__le32 checksum_offset;		/* checksum offset inside super block */
69 	__le64 block_count;		/* total # of user blocks */
70 	__le32 section_count;		/* total # of sections */
71 	__le32 segment_count;		/* total # of segments */
72 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
73 	__le32 segment_count_sit;	/* # of segments for SIT */
74 	__le32 segment_count_nat;	/* # of segments for NAT */
75 	__le32 segment_count_ssa;	/* # of segments for SSA */
76 	__le32 segment_count_main;	/* # of segments for main area */
77 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
78 	__le32 cp_blkaddr;		/* start block address of checkpoint */
79 	__le32 sit_blkaddr;		/* start block address of SIT */
80 	__le32 nat_blkaddr;		/* start block address of NAT */
81 	__le32 ssa_blkaddr;		/* start block address of SSA */
82 	__le32 main_blkaddr;		/* start block address of main area */
83 	__le32 root_ino;		/* root inode number */
84 	__le32 node_ino;		/* node inode number */
85 	__le32 meta_ino;		/* meta inode number */
86 	__u8 uuid[16];			/* 128-bit uuid for volume */
87 	__le16 volume_name[512];	/* volume name */
88 	__le32 extension_count;		/* # of extensions below */
89 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
90 	__le32 cp_payload;
91 	__u8 version[VERSION_LEN];	/* the kernel version */
92 	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
93 	__le32 feature;			/* defined features */
94 	__u8 encryption_level;		/* versioning level for encryption */
95 	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
96 	__u8 reserved[871];		/* valid reserved region */
97 } __packed;
98 
99 /*
100  * For checkpoint
101  */
102 #define CP_FASTBOOT_FLAG	0x00000020
103 #define CP_FSCK_FLAG		0x00000010
104 #define CP_ERROR_FLAG		0x00000008
105 #define CP_COMPACT_SUM_FLAG	0x00000004
106 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
107 #define CP_UMOUNT_FLAG		0x00000001
108 
109 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
110 
111 struct f2fs_checkpoint {
112 	__le64 checkpoint_ver;		/* checkpoint block version number */
113 	__le64 user_block_count;	/* # of user blocks */
114 	__le64 valid_block_count;	/* # of valid blocks in main area */
115 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
116 	__le32 overprov_segment_count;	/* # of overprovision segments */
117 	__le32 free_segment_count;	/* # of free segments in main area */
118 
119 	/* information of current node segments */
120 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
121 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
122 	/* information of current data segments */
123 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
124 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
125 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
126 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
127 	__le32 cp_pack_start_sum;	/* start block number of data summary */
128 	__le32 valid_node_count;	/* Total number of valid nodes */
129 	__le32 valid_inode_count;	/* Total number of valid inodes */
130 	__le32 next_free_nid;		/* Next free node number */
131 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
132 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
133 	__le32 checksum_offset;		/* checksum offset inside cp block */
134 	__le64 elapsed_time;		/* mounted time */
135 	/* allocation type of current segment */
136 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
137 
138 	/* SIT and NAT version bitmap */
139 	unsigned char sit_nat_version_bitmap[1];
140 } __packed;
141 
142 /*
143  * For orphan inode management
144  */
145 #define F2FS_ORPHANS_PER_BLOCK	1020
146 
147 #define GET_ORPHAN_BLOCKS(n)	((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
148 					F2FS_ORPHANS_PER_BLOCK)
149 
150 struct f2fs_orphan_block {
151 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
152 	__le32 reserved;	/* reserved */
153 	__le16 blk_addr;	/* block index in current CP */
154 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
155 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
156 	__le32 check_sum;	/* CRC32 for orphan inode block */
157 } __packed;
158 
159 /*
160  * For NODE structure
161  */
162 struct f2fs_extent {
163 	__le32 fofs;		/* start file offset of the extent */
164 	__le32 blk;		/* start block address of the extent */
165 	__le32 len;		/* lengh of the extent */
166 } __packed;
167 
168 #define F2FS_NAME_LEN		255
169 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
170 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
171 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
172 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
173 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
174 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
175 
176 #define ADDRS_PER_PAGE(page, fi)	\
177 	(IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
178 
179 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
180 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
181 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
182 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
183 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
184 
185 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
186 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
187 #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
188 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
189 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
190 
191 #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
192 						F2FS_INLINE_XATTR_ADDRS - 1))
193 
194 struct f2fs_inode {
195 	__le16 i_mode;			/* file mode */
196 	__u8 i_advise;			/* file hints */
197 	__u8 i_inline;			/* file inline flags */
198 	__le32 i_uid;			/* user ID */
199 	__le32 i_gid;			/* group ID */
200 	__le32 i_links;			/* links count */
201 	__le64 i_size;			/* file size in bytes */
202 	__le64 i_blocks;		/* file size in blocks */
203 	__le64 i_atime;			/* access time */
204 	__le64 i_ctime;			/* change time */
205 	__le64 i_mtime;			/* modification time */
206 	__le32 i_atime_nsec;		/* access time in nano scale */
207 	__le32 i_ctime_nsec;		/* change time in nano scale */
208 	__le32 i_mtime_nsec;		/* modification time in nano scale */
209 	__le32 i_generation;		/* file version (for NFS) */
210 	__le32 i_current_depth;		/* only for directory depth */
211 	__le32 i_xattr_nid;		/* nid to save xattr */
212 	__le32 i_flags;			/* file attributes */
213 	__le32 i_pino;			/* parent inode number */
214 	__le32 i_namelen;		/* file name length */
215 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
216 	__u8 i_dir_level;		/* dentry_level for large dir */
217 
218 	struct f2fs_extent i_ext;	/* caching a largest extent */
219 
220 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
221 
222 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
223 						double_indirect(1) node id */
224 } __packed;
225 
226 struct direct_node {
227 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
228 } __packed;
229 
230 struct indirect_node {
231 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
232 } __packed;
233 
234 enum {
235 	COLD_BIT_SHIFT = 0,
236 	FSYNC_BIT_SHIFT,
237 	DENT_BIT_SHIFT,
238 	OFFSET_BIT_SHIFT
239 };
240 
241 #define OFFSET_BIT_MASK		(0x07)	/* (0x01 << OFFSET_BIT_SHIFT) - 1 */
242 
243 struct node_footer {
244 	__le32 nid;		/* node id */
245 	__le32 ino;		/* inode nunmber */
246 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
247 	__le64 cp_ver;		/* checkpoint version */
248 	__le32 next_blkaddr;	/* next node page block address */
249 } __packed;
250 
251 struct f2fs_node {
252 	/* can be one of three types: inode, direct, and indirect types */
253 	union {
254 		struct f2fs_inode i;
255 		struct direct_node dn;
256 		struct indirect_node in;
257 	};
258 	struct node_footer footer;
259 } __packed;
260 
261 /*
262  * For NAT entries
263  */
264 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
265 
266 struct f2fs_nat_entry {
267 	__u8 version;		/* latest version of cached nat entry */
268 	__le32 ino;		/* inode number */
269 	__le32 block_addr;	/* block address */
270 } __packed;
271 
272 struct f2fs_nat_block {
273 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
274 } __packed;
275 
276 /*
277  * For SIT entries
278  *
279  * Each segment is 2MB in size by default so that a bitmap for validity of
280  * there-in blocks should occupy 64 bytes, 512 bits.
281  * Not allow to change this.
282  */
283 #define SIT_VBLOCK_MAP_SIZE 64
284 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
285 
286 /*
287  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
288  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
289  * [9:0] : valid block count
290  */
291 #define SIT_VBLOCKS_SHIFT	10
292 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
293 #define GET_SIT_VBLOCKS(raw_sit)				\
294 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
295 #define GET_SIT_TYPE(raw_sit)					\
296 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
297 	 >> SIT_VBLOCKS_SHIFT)
298 
299 struct f2fs_sit_entry {
300 	__le16 vblocks;				/* reference above */
301 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
302 	__le64 mtime;				/* segment age for cleaning */
303 } __packed;
304 
305 struct f2fs_sit_block {
306 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
307 } __packed;
308 
309 /*
310  * For segment summary
311  *
312  * One summary block contains exactly 512 summary entries, which represents
313  * exactly 2MB segment by default. Not allow to change the basic units.
314  *
315  * NOTE: For initializing fields, you must use set_summary
316  *
317  * - If data page, nid represents dnode's nid
318  * - If node page, nid represents the node page's nid.
319  *
320  * The ofs_in_node is used by only data page. It represents offset
321  * from node's page's beginning to get a data block address.
322  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
323  */
324 #define ENTRIES_IN_SUM		512
325 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
326 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
327 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
328 
329 /* a summary entry for a 4KB-sized block in a segment */
330 struct f2fs_summary {
331 	__le32 nid;		/* parent node id */
332 	union {
333 		__u8 reserved[3];
334 		struct {
335 			__u8 version;		/* node version number */
336 			__le16 ofs_in_node;	/* block index in parent node */
337 		} __packed;
338 	};
339 } __packed;
340 
341 /* summary block type, node or data, is stored to the summary_footer */
342 #define SUM_TYPE_NODE		(1)
343 #define SUM_TYPE_DATA		(0)
344 
345 struct summary_footer {
346 	unsigned char entry_type;	/* SUM_TYPE_XXX */
347 	__u32 check_sum;		/* summary checksum */
348 } __packed;
349 
350 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
351 				SUM_ENTRY_SIZE)
352 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
353 				sizeof(struct nat_journal_entry))
354 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
355 				sizeof(struct nat_journal_entry))
356 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
357 				sizeof(struct sit_journal_entry))
358 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
359 				sizeof(struct sit_journal_entry))
360 /*
361  * frequently updated NAT/SIT entries can be stored in the spare area in
362  * summary blocks
363  */
364 enum {
365 	NAT_JOURNAL = 0,
366 	SIT_JOURNAL
367 };
368 
369 struct nat_journal_entry {
370 	__le32 nid;
371 	struct f2fs_nat_entry ne;
372 } __packed;
373 
374 struct nat_journal {
375 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
376 	__u8 reserved[NAT_JOURNAL_RESERVED];
377 } __packed;
378 
379 struct sit_journal_entry {
380 	__le32 segno;
381 	struct f2fs_sit_entry se;
382 } __packed;
383 
384 struct sit_journal {
385 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
386 	__u8 reserved[SIT_JOURNAL_RESERVED];
387 } __packed;
388 
389 /* 4KB-sized summary block structure */
390 struct f2fs_summary_block {
391 	struct f2fs_summary entries[ENTRIES_IN_SUM];
392 	union {
393 		__le16 n_nats;
394 		__le16 n_sits;
395 	};
396 	/* spare area is used by NAT or SIT journals */
397 	union {
398 		struct nat_journal nat_j;
399 		struct sit_journal sit_j;
400 	};
401 	struct summary_footer footer;
402 } __packed;
403 
404 /*
405  * For directory operations
406  */
407 #define F2FS_DOT_HASH		0
408 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
409 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
410 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
411 
412 typedef __le32	f2fs_hash_t;
413 
414 /* One directory entry slot covers 8bytes-long file name */
415 #define F2FS_SLOT_LEN		8
416 #define F2FS_SLOT_LEN_BITS	3
417 
418 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
419 
420 /* MAX level for dir lookup */
421 #define MAX_DIR_HASH_DEPTH	63
422 
423 /* MAX buckets in one level of dir */
424 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
425 
426 /*
427  * space utilization of regular dentry and inline dentry
428  *		regular dentry			inline dentry
429  * bitmap	1 * 27 = 27			1 * 23 = 23
430  * reserved	1 * 3 = 3			1 * 7 = 7
431  * dentry	11 * 214 = 2354			11 * 182 = 2002
432  * filename	8 * 214 = 1712			8 * 182 = 1456
433  * total	4096				3488
434  *
435  * Note: there are more reserved space in inline dentry than in regular
436  * dentry, when converting inline dentry we should handle this carefully.
437  */
438 #define NR_DENTRY_IN_BLOCK	214	/* the number of dentry in a block */
439 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
440 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
441 					BITS_PER_BYTE)
442 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
443 				F2FS_SLOT_LEN) * \
444 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
445 
446 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
447 struct f2fs_dir_entry {
448 	__le32 hash_code;	/* hash code of file name */
449 	__le32 ino;		/* inode number */
450 	__le16 name_len;	/* lengh of file name */
451 	__u8 file_type;		/* file type */
452 } __packed;
453 
454 /* 4KB-sized directory entry block */
455 struct f2fs_dentry_block {
456 	/* validity bitmap for directory entries in each block */
457 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
458 	__u8 reserved[SIZE_OF_RESERVED];
459 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
460 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
461 } __packed;
462 
463 /* for inline dir */
464 #define NR_INLINE_DENTRY	(MAX_INLINE_DATA * BITS_PER_BYTE / \
465 				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
466 				BITS_PER_BYTE + 1))
467 #define INLINE_DENTRY_BITMAP_SIZE	((NR_INLINE_DENTRY + \
468 					BITS_PER_BYTE - 1) / BITS_PER_BYTE)
469 #define INLINE_RESERVED_SIZE	(MAX_INLINE_DATA - \
470 				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
471 				NR_INLINE_DENTRY + INLINE_DENTRY_BITMAP_SIZE))
472 
473 /* inline directory entry structure */
474 struct f2fs_inline_dentry {
475 	__u8 dentry_bitmap[INLINE_DENTRY_BITMAP_SIZE];
476 	__u8 reserved[INLINE_RESERVED_SIZE];
477 	struct f2fs_dir_entry dentry[NR_INLINE_DENTRY];
478 	__u8 filename[NR_INLINE_DENTRY][F2FS_SLOT_LEN];
479 } __packed;
480 
481 /* file types used in inode_info->flags */
482 enum {
483 	F2FS_FT_UNKNOWN,
484 	F2FS_FT_REG_FILE,
485 	F2FS_FT_DIR,
486 	F2FS_FT_CHRDEV,
487 	F2FS_FT_BLKDEV,
488 	F2FS_FT_FIFO,
489 	F2FS_FT_SOCK,
490 	F2FS_FT_SYMLINK,
491 	F2FS_FT_MAX
492 };
493 
494 #endif  /* _LINUX_F2FS_FS_H */
495