xref: /linux/include/linux/f2fs_fs.h (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
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_LOG_SECTOR_SIZE		9	/* 9 bits for 512 byte */
19 #define F2FS_LOG_SECTORS_PER_BLOCK	3	/* 4KB: F2FS_BLKSIZE */
20 #define F2FS_BLKSIZE			4096	/* support only 4KB block */
21 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
22 #define F2FS_BLK_ALIGN(x)	(((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
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 
27 /* 0, 1(node nid), 2(meta nid) are reserved node id */
28 #define F2FS_RESERVED_NODE_NUM		3
29 
30 #define F2FS_ROOT_INO(sbi)	(sbi->root_ino_num)
31 #define F2FS_NODE_INO(sbi)	(sbi->node_ino_num)
32 #define F2FS_META_INO(sbi)	(sbi->meta_ino_num)
33 
34 /* This flag is used by node and meta inodes, and by recovery */
35 #define GFP_F2FS_ZERO	(GFP_NOFS | __GFP_ZERO)
36 
37 /*
38  * For further optimization on multi-head logs, on-disk layout supports maximum
39  * 16 logs by default. The number, 16, is expected to cover all the cases
40  * enoughly. The implementaion currently uses no more than 6 logs.
41  * Half the logs are used for nodes, and the other half are used for data.
42  */
43 #define MAX_ACTIVE_LOGS	16
44 #define MAX_ACTIVE_NODE_LOGS	8
45 #define MAX_ACTIVE_DATA_LOGS	8
46 
47 /*
48  * For superblock
49  */
50 struct f2fs_super_block {
51 	__le32 magic;			/* Magic Number */
52 	__le16 major_ver;		/* Major Version */
53 	__le16 minor_ver;		/* Minor Version */
54 	__le32 log_sectorsize;		/* log2 sector size in bytes */
55 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
56 	__le32 log_blocksize;		/* log2 block size in bytes */
57 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
58 	__le32 segs_per_sec;		/* # of segments per section */
59 	__le32 secs_per_zone;		/* # of sections per zone */
60 	__le32 checksum_offset;		/* checksum offset inside super block */
61 	__le64 block_count;		/* total # of user blocks */
62 	__le32 section_count;		/* total # of sections */
63 	__le32 segment_count;		/* total # of segments */
64 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
65 	__le32 segment_count_sit;	/* # of segments for SIT */
66 	__le32 segment_count_nat;	/* # of segments for NAT */
67 	__le32 segment_count_ssa;	/* # of segments for SSA */
68 	__le32 segment_count_main;	/* # of segments for main area */
69 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
70 	__le32 cp_blkaddr;		/* start block address of checkpoint */
71 	__le32 sit_blkaddr;		/* start block address of SIT */
72 	__le32 nat_blkaddr;		/* start block address of NAT */
73 	__le32 ssa_blkaddr;		/* start block address of SSA */
74 	__le32 main_blkaddr;		/* start block address of main area */
75 	__le32 root_ino;		/* root inode number */
76 	__le32 node_ino;		/* node inode number */
77 	__le32 meta_ino;		/* meta inode number */
78 	__u8 uuid[16];			/* 128-bit uuid for volume */
79 	__le16 volume_name[512];	/* volume name */
80 	__le32 extension_count;		/* # of extensions below */
81 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
82 	__le32 cp_payload;
83 } __packed;
84 
85 /*
86  * For checkpoint
87  */
88 #define CP_ERROR_FLAG		0x00000008
89 #define CP_COMPACT_SUM_FLAG	0x00000004
90 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
91 #define CP_UMOUNT_FLAG		0x00000001
92 
93 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
94 
95 struct f2fs_checkpoint {
96 	__le64 checkpoint_ver;		/* checkpoint block version number */
97 	__le64 user_block_count;	/* # of user blocks */
98 	__le64 valid_block_count;	/* # of valid blocks in main area */
99 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
100 	__le32 overprov_segment_count;	/* # of overprovision segments */
101 	__le32 free_segment_count;	/* # of free segments in main area */
102 
103 	/* information of current node segments */
104 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
105 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
106 	/* information of current data segments */
107 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
108 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
109 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
110 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
111 	__le32 cp_pack_start_sum;	/* start block number of data summary */
112 	__le32 valid_node_count;	/* Total number of valid nodes */
113 	__le32 valid_inode_count;	/* Total number of valid inodes */
114 	__le32 next_free_nid;		/* Next free node number */
115 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
116 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
117 	__le32 checksum_offset;		/* checksum offset inside cp block */
118 	__le64 elapsed_time;		/* mounted time */
119 	/* allocation type of current segment */
120 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
121 
122 	/* SIT and NAT version bitmap */
123 	unsigned char sit_nat_version_bitmap[1];
124 } __packed;
125 
126 /*
127  * For orphan inode management
128  */
129 #define F2FS_ORPHANS_PER_BLOCK	1020
130 
131 #define GET_ORPHAN_BLOCKS(n)	((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
132 					F2FS_ORPHANS_PER_BLOCK)
133 
134 struct f2fs_orphan_block {
135 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
136 	__le32 reserved;	/* reserved */
137 	__le16 blk_addr;	/* block index in current CP */
138 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
139 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
140 	__le32 check_sum;	/* CRC32 for orphan inode block */
141 } __packed;
142 
143 /*
144  * For NODE structure
145  */
146 struct f2fs_extent {
147 	__le32 fofs;		/* start file offset of the extent */
148 	__le32 blk_addr;	/* start block address of the extent */
149 	__le32 len;		/* lengh of the extent */
150 } __packed;
151 
152 #define F2FS_NAME_LEN		255
153 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
154 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
155 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
156 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
157 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
158 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
159 
160 #define ADDRS_PER_PAGE(page, fi)	\
161 	(IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
162 
163 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
164 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
165 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
166 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
167 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
168 
169 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
170 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
171 
172 #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
173 						F2FS_INLINE_XATTR_ADDRS - 1))
174 
175 #define INLINE_DATA_OFFSET	(PAGE_CACHE_SIZE - sizeof(struct node_footer) -\
176 				sizeof(__le32) * (DEF_ADDRS_PER_INODE + \
177 				DEF_NIDS_PER_INODE - 1))
178 
179 struct f2fs_inode {
180 	__le16 i_mode;			/* file mode */
181 	__u8 i_advise;			/* file hints */
182 	__u8 i_inline;			/* file inline flags */
183 	__le32 i_uid;			/* user ID */
184 	__le32 i_gid;			/* group ID */
185 	__le32 i_links;			/* links count */
186 	__le64 i_size;			/* file size in bytes */
187 	__le64 i_blocks;		/* file size in blocks */
188 	__le64 i_atime;			/* access time */
189 	__le64 i_ctime;			/* change time */
190 	__le64 i_mtime;			/* modification time */
191 	__le32 i_atime_nsec;		/* access time in nano scale */
192 	__le32 i_ctime_nsec;		/* change time in nano scale */
193 	__le32 i_mtime_nsec;		/* modification time in nano scale */
194 	__le32 i_generation;		/* file version (for NFS) */
195 	__le32 i_current_depth;		/* only for directory depth */
196 	__le32 i_xattr_nid;		/* nid to save xattr */
197 	__le32 i_flags;			/* file attributes */
198 	__le32 i_pino;			/* parent inode number */
199 	__le32 i_namelen;		/* file name length */
200 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
201 	__u8 i_dir_level;		/* dentry_level for large dir */
202 
203 	struct f2fs_extent i_ext;	/* caching a largest extent */
204 
205 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
206 
207 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
208 						double_indirect(1) node id */
209 } __packed;
210 
211 struct direct_node {
212 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
213 } __packed;
214 
215 struct indirect_node {
216 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
217 } __packed;
218 
219 enum {
220 	COLD_BIT_SHIFT = 0,
221 	FSYNC_BIT_SHIFT,
222 	DENT_BIT_SHIFT,
223 	OFFSET_BIT_SHIFT
224 };
225 
226 struct node_footer {
227 	__le32 nid;		/* node id */
228 	__le32 ino;		/* inode nunmber */
229 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
230 	__le64 cp_ver;		/* checkpoint version */
231 	__le32 next_blkaddr;	/* next node page block address */
232 } __packed;
233 
234 struct f2fs_node {
235 	/* can be one of three types: inode, direct, and indirect types */
236 	union {
237 		struct f2fs_inode i;
238 		struct direct_node dn;
239 		struct indirect_node in;
240 	};
241 	struct node_footer footer;
242 } __packed;
243 
244 /*
245  * For NAT entries
246  */
247 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
248 
249 struct f2fs_nat_entry {
250 	__u8 version;		/* latest version of cached nat entry */
251 	__le32 ino;		/* inode number */
252 	__le32 block_addr;	/* block address */
253 } __packed;
254 
255 struct f2fs_nat_block {
256 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
257 } __packed;
258 
259 /*
260  * For SIT entries
261  *
262  * Each segment is 2MB in size by default so that a bitmap for validity of
263  * there-in blocks should occupy 64 bytes, 512 bits.
264  * Not allow to change this.
265  */
266 #define SIT_VBLOCK_MAP_SIZE 64
267 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
268 
269 /*
270  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
271  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
272  * [9:0] : valid block count
273  */
274 #define SIT_VBLOCKS_SHIFT	10
275 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
276 #define GET_SIT_VBLOCKS(raw_sit)				\
277 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
278 #define GET_SIT_TYPE(raw_sit)					\
279 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
280 	 >> SIT_VBLOCKS_SHIFT)
281 
282 struct f2fs_sit_entry {
283 	__le16 vblocks;				/* reference above */
284 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
285 	__le64 mtime;				/* segment age for cleaning */
286 } __packed;
287 
288 struct f2fs_sit_block {
289 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
290 } __packed;
291 
292 /*
293  * For segment summary
294  *
295  * One summary block contains exactly 512 summary entries, which represents
296  * exactly 2MB segment by default. Not allow to change the basic units.
297  *
298  * NOTE: For initializing fields, you must use set_summary
299  *
300  * - If data page, nid represents dnode's nid
301  * - If node page, nid represents the node page's nid.
302  *
303  * The ofs_in_node is used by only data page. It represents offset
304  * from node's page's beginning to get a data block address.
305  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
306  */
307 #define ENTRIES_IN_SUM		512
308 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
309 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
310 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
311 
312 /* a summary entry for a 4KB-sized block in a segment */
313 struct f2fs_summary {
314 	__le32 nid;		/* parent node id */
315 	union {
316 		__u8 reserved[3];
317 		struct {
318 			__u8 version;		/* node version number */
319 			__le16 ofs_in_node;	/* block index in parent node */
320 		} __packed;
321 	};
322 } __packed;
323 
324 /* summary block type, node or data, is stored to the summary_footer */
325 #define SUM_TYPE_NODE		(1)
326 #define SUM_TYPE_DATA		(0)
327 
328 struct summary_footer {
329 	unsigned char entry_type;	/* SUM_TYPE_XXX */
330 	__u32 check_sum;		/* summary checksum */
331 } __packed;
332 
333 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
334 				SUM_ENTRY_SIZE)
335 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
336 				sizeof(struct nat_journal_entry))
337 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
338 				sizeof(struct nat_journal_entry))
339 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
340 				sizeof(struct sit_journal_entry))
341 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
342 				sizeof(struct sit_journal_entry))
343 /*
344  * frequently updated NAT/SIT entries can be stored in the spare area in
345  * summary blocks
346  */
347 enum {
348 	NAT_JOURNAL = 0,
349 	SIT_JOURNAL
350 };
351 
352 struct nat_journal_entry {
353 	__le32 nid;
354 	struct f2fs_nat_entry ne;
355 } __packed;
356 
357 struct nat_journal {
358 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
359 	__u8 reserved[NAT_JOURNAL_RESERVED];
360 } __packed;
361 
362 struct sit_journal_entry {
363 	__le32 segno;
364 	struct f2fs_sit_entry se;
365 } __packed;
366 
367 struct sit_journal {
368 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
369 	__u8 reserved[SIT_JOURNAL_RESERVED];
370 } __packed;
371 
372 /* 4KB-sized summary block structure */
373 struct f2fs_summary_block {
374 	struct f2fs_summary entries[ENTRIES_IN_SUM];
375 	union {
376 		__le16 n_nats;
377 		__le16 n_sits;
378 	};
379 	/* spare area is used by NAT or SIT journals */
380 	union {
381 		struct nat_journal nat_j;
382 		struct sit_journal sit_j;
383 	};
384 	struct summary_footer footer;
385 } __packed;
386 
387 /*
388  * For directory operations
389  */
390 #define F2FS_DOT_HASH		0
391 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
392 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
393 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
394 
395 typedef __le32	f2fs_hash_t;
396 
397 /* One directory entry slot covers 8bytes-long file name */
398 #define F2FS_SLOT_LEN		8
399 #define F2FS_SLOT_LEN_BITS	3
400 
401 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
402 
403 /* the number of dentry in a block */
404 #define NR_DENTRY_IN_BLOCK	214
405 
406 /* MAX level for dir lookup */
407 #define MAX_DIR_HASH_DEPTH	63
408 
409 /* MAX buckets in one level of dir */
410 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
411 
412 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
413 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
414 					BITS_PER_BYTE)
415 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
416 				F2FS_SLOT_LEN) * \
417 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
418 
419 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
420 struct f2fs_dir_entry {
421 	__le32 hash_code;	/* hash code of file name */
422 	__le32 ino;		/* inode number */
423 	__le16 name_len;	/* lengh of file name */
424 	__u8 file_type;		/* file type */
425 } __packed;
426 
427 /* 4KB-sized directory entry block */
428 struct f2fs_dentry_block {
429 	/* validity bitmap for directory entries in each block */
430 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
431 	__u8 reserved[SIZE_OF_RESERVED];
432 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
433 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
434 } __packed;
435 
436 /* file types used in inode_info->flags */
437 enum {
438 	F2FS_FT_UNKNOWN,
439 	F2FS_FT_REG_FILE,
440 	F2FS_FT_DIR,
441 	F2FS_FT_CHRDEV,
442 	F2FS_FT_BLKDEV,
443 	F2FS_FT_FIFO,
444 	F2FS_FT_SOCK,
445 	F2FS_FT_SYMLINK,
446 	F2FS_FT_MAX
447 };
448 
449 #endif  /* _LINUX_F2FS_FS_H */
450