xref: /linux/include/linux/f2fs_fs.h (revision 988b0c541ed8b1c633c4d4df7169010635942e18)
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 #define F2FS_ROOT_INO(sbi)	(sbi->root_ino_num)
28 #define F2FS_NODE_INO(sbi)	(sbi->node_ino_num)
29 #define F2FS_META_INO(sbi)	(sbi->meta_ino_num)
30 
31 /* This flag is used by node and meta inodes, and by recovery */
32 #define GFP_F2FS_ZERO	(GFP_NOFS | __GFP_ZERO)
33 
34 /*
35  * For further optimization on multi-head logs, on-disk layout supports maximum
36  * 16 logs by default. The number, 16, is expected to cover all the cases
37  * enoughly. The implementaion currently uses no more than 6 logs.
38  * Half the logs are used for nodes, and the other half are used for data.
39  */
40 #define MAX_ACTIVE_LOGS	16
41 #define MAX_ACTIVE_NODE_LOGS	8
42 #define MAX_ACTIVE_DATA_LOGS	8
43 
44 /*
45  * For superblock
46  */
47 struct f2fs_super_block {
48 	__le32 magic;			/* Magic Number */
49 	__le16 major_ver;		/* Major Version */
50 	__le16 minor_ver;		/* Minor Version */
51 	__le32 log_sectorsize;		/* log2 sector size in bytes */
52 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
53 	__le32 log_blocksize;		/* log2 block size in bytes */
54 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
55 	__le32 segs_per_sec;		/* # of segments per section */
56 	__le32 secs_per_zone;		/* # of sections per zone */
57 	__le32 checksum_offset;		/* checksum offset inside super block */
58 	__le64 block_count;		/* total # of user blocks */
59 	__le32 section_count;		/* total # of sections */
60 	__le32 segment_count;		/* total # of segments */
61 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
62 	__le32 segment_count_sit;	/* # of segments for SIT */
63 	__le32 segment_count_nat;	/* # of segments for NAT */
64 	__le32 segment_count_ssa;	/* # of segments for SSA */
65 	__le32 segment_count_main;	/* # of segments for main area */
66 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
67 	__le32 cp_blkaddr;		/* start block address of checkpoint */
68 	__le32 sit_blkaddr;		/* start block address of SIT */
69 	__le32 nat_blkaddr;		/* start block address of NAT */
70 	__le32 ssa_blkaddr;		/* start block address of SSA */
71 	__le32 main_blkaddr;		/* start block address of main area */
72 	__le32 root_ino;		/* root inode number */
73 	__le32 node_ino;		/* node inode number */
74 	__le32 meta_ino;		/* meta inode number */
75 	__u8 uuid[16];			/* 128-bit uuid for volume */
76 	__le16 volume_name[512];	/* volume name */
77 	__le32 extension_count;		/* # of extensions below */
78 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
79 	__le32 cp_payload;
80 } __packed;
81 
82 /*
83  * For checkpoint
84  */
85 #define CP_ERROR_FLAG		0x00000008
86 #define CP_COMPACT_SUM_FLAG	0x00000004
87 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
88 #define CP_UMOUNT_FLAG		0x00000001
89 
90 struct f2fs_checkpoint {
91 	__le64 checkpoint_ver;		/* checkpoint block version number */
92 	__le64 user_block_count;	/* # of user blocks */
93 	__le64 valid_block_count;	/* # of valid blocks in main area */
94 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
95 	__le32 overprov_segment_count;	/* # of overprovision segments */
96 	__le32 free_segment_count;	/* # of free segments in main area */
97 
98 	/* information of current node segments */
99 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
100 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
101 	/* information of current data segments */
102 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
103 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
104 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
105 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
106 	__le32 cp_pack_start_sum;	/* start block number of data summary */
107 	__le32 valid_node_count;	/* Total number of valid nodes */
108 	__le32 valid_inode_count;	/* Total number of valid inodes */
109 	__le32 next_free_nid;		/* Next free node number */
110 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
111 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
112 	__le32 checksum_offset;		/* checksum offset inside cp block */
113 	__le64 elapsed_time;		/* mounted time */
114 	/* allocation type of current segment */
115 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
116 
117 	/* SIT and NAT version bitmap */
118 	unsigned char sit_nat_version_bitmap[1];
119 } __packed;
120 
121 /*
122  * For orphan inode management
123  */
124 #define F2FS_ORPHANS_PER_BLOCK	1020
125 
126 struct f2fs_orphan_block {
127 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
128 	__le32 reserved;	/* reserved */
129 	__le16 blk_addr;	/* block index in current CP */
130 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
131 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
132 	__le32 check_sum;	/* CRC32 for orphan inode block */
133 } __packed;
134 
135 /*
136  * For NODE structure
137  */
138 struct f2fs_extent {
139 	__le32 fofs;		/* start file offset of the extent */
140 	__le32 blk_addr;	/* start block address of the extent */
141 	__le32 len;		/* lengh of the extent */
142 } __packed;
143 
144 #define F2FS_NAME_LEN		255
145 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
146 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
147 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
148 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
149 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
150 
151 #define ADDRS_PER_PAGE(page, fi)	\
152 	(IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
153 
154 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
155 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
156 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
157 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
158 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
159 
160 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
161 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
162 
163 #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
164 						F2FS_INLINE_XATTR_ADDRS - 1))
165 
166 #define INLINE_DATA_OFFSET	(PAGE_CACHE_SIZE - sizeof(struct node_footer) \
167 			- sizeof(__le32) * (DEF_ADDRS_PER_INODE + 5 - 1))
168 
169 struct f2fs_inode {
170 	__le16 i_mode;			/* file mode */
171 	__u8 i_advise;			/* file hints */
172 	__u8 i_inline;			/* file inline flags */
173 	__le32 i_uid;			/* user ID */
174 	__le32 i_gid;			/* group ID */
175 	__le32 i_links;			/* links count */
176 	__le64 i_size;			/* file size in bytes */
177 	__le64 i_blocks;		/* file size in blocks */
178 	__le64 i_atime;			/* access time */
179 	__le64 i_ctime;			/* change time */
180 	__le64 i_mtime;			/* modification time */
181 	__le32 i_atime_nsec;		/* access time in nano scale */
182 	__le32 i_ctime_nsec;		/* change time in nano scale */
183 	__le32 i_mtime_nsec;		/* modification time in nano scale */
184 	__le32 i_generation;		/* file version (for NFS) */
185 	__le32 i_current_depth;		/* only for directory depth */
186 	__le32 i_xattr_nid;		/* nid to save xattr */
187 	__le32 i_flags;			/* file attributes */
188 	__le32 i_pino;			/* parent inode number */
189 	__le32 i_namelen;		/* file name length */
190 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
191 	__u8 i_dir_level;		/* dentry_level for large dir */
192 
193 	struct f2fs_extent i_ext;	/* caching a largest extent */
194 
195 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
196 
197 	__le32 i_nid[5];		/* direct(2), indirect(2),
198 						double_indirect(1) node id */
199 } __packed;
200 
201 struct direct_node {
202 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
203 } __packed;
204 
205 struct indirect_node {
206 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
207 } __packed;
208 
209 enum {
210 	COLD_BIT_SHIFT = 0,
211 	FSYNC_BIT_SHIFT,
212 	DENT_BIT_SHIFT,
213 	OFFSET_BIT_SHIFT
214 };
215 
216 struct node_footer {
217 	__le32 nid;		/* node id */
218 	__le32 ino;		/* inode nunmber */
219 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
220 	__le64 cp_ver;		/* checkpoint version */
221 	__le32 next_blkaddr;	/* next node page block address */
222 } __packed;
223 
224 struct f2fs_node {
225 	/* can be one of three types: inode, direct, and indirect types */
226 	union {
227 		struct f2fs_inode i;
228 		struct direct_node dn;
229 		struct indirect_node in;
230 	};
231 	struct node_footer footer;
232 } __packed;
233 
234 /*
235  * For NAT entries
236  */
237 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
238 
239 struct f2fs_nat_entry {
240 	__u8 version;		/* latest version of cached nat entry */
241 	__le32 ino;		/* inode number */
242 	__le32 block_addr;	/* block address */
243 } __packed;
244 
245 struct f2fs_nat_block {
246 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
247 } __packed;
248 
249 /*
250  * For SIT entries
251  *
252  * Each segment is 2MB in size by default so that a bitmap for validity of
253  * there-in blocks should occupy 64 bytes, 512 bits.
254  * Not allow to change this.
255  */
256 #define SIT_VBLOCK_MAP_SIZE 64
257 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
258 
259 /*
260  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
261  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
262  * [9:0] : valid block count
263  */
264 #define SIT_VBLOCKS_SHIFT	10
265 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
266 #define GET_SIT_VBLOCKS(raw_sit)				\
267 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
268 #define GET_SIT_TYPE(raw_sit)					\
269 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
270 	 >> SIT_VBLOCKS_SHIFT)
271 
272 struct f2fs_sit_entry {
273 	__le16 vblocks;				/* reference above */
274 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
275 	__le64 mtime;				/* segment age for cleaning */
276 } __packed;
277 
278 struct f2fs_sit_block {
279 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
280 } __packed;
281 
282 /*
283  * For segment summary
284  *
285  * One summary block contains exactly 512 summary entries, which represents
286  * exactly 2MB segment by default. Not allow to change the basic units.
287  *
288  * NOTE: For initializing fields, you must use set_summary
289  *
290  * - If data page, nid represents dnode's nid
291  * - If node page, nid represents the node page's nid.
292  *
293  * The ofs_in_node is used by only data page. It represents offset
294  * from node's page's beginning to get a data block address.
295  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
296  */
297 #define ENTRIES_IN_SUM		512
298 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
299 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
300 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
301 
302 /* a summary entry for a 4KB-sized block in a segment */
303 struct f2fs_summary {
304 	__le32 nid;		/* parent node id */
305 	union {
306 		__u8 reserved[3];
307 		struct {
308 			__u8 version;		/* node version number */
309 			__le16 ofs_in_node;	/* block index in parent node */
310 		} __packed;
311 	};
312 } __packed;
313 
314 /* summary block type, node or data, is stored to the summary_footer */
315 #define SUM_TYPE_NODE		(1)
316 #define SUM_TYPE_DATA		(0)
317 
318 struct summary_footer {
319 	unsigned char entry_type;	/* SUM_TYPE_XXX */
320 	__u32 check_sum;		/* summary checksum */
321 } __packed;
322 
323 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
324 				SUM_ENTRY_SIZE)
325 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
326 				sizeof(struct nat_journal_entry))
327 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
328 				sizeof(struct nat_journal_entry))
329 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
330 				sizeof(struct sit_journal_entry))
331 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
332 				sizeof(struct sit_journal_entry))
333 /*
334  * frequently updated NAT/SIT entries can be stored in the spare area in
335  * summary blocks
336  */
337 enum {
338 	NAT_JOURNAL = 0,
339 	SIT_JOURNAL
340 };
341 
342 struct nat_journal_entry {
343 	__le32 nid;
344 	struct f2fs_nat_entry ne;
345 } __packed;
346 
347 struct nat_journal {
348 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
349 	__u8 reserved[NAT_JOURNAL_RESERVED];
350 } __packed;
351 
352 struct sit_journal_entry {
353 	__le32 segno;
354 	struct f2fs_sit_entry se;
355 } __packed;
356 
357 struct sit_journal {
358 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
359 	__u8 reserved[SIT_JOURNAL_RESERVED];
360 } __packed;
361 
362 /* 4KB-sized summary block structure */
363 struct f2fs_summary_block {
364 	struct f2fs_summary entries[ENTRIES_IN_SUM];
365 	union {
366 		__le16 n_nats;
367 		__le16 n_sits;
368 	};
369 	/* spare area is used by NAT or SIT journals */
370 	union {
371 		struct nat_journal nat_j;
372 		struct sit_journal sit_j;
373 	};
374 	struct summary_footer footer;
375 } __packed;
376 
377 /*
378  * For directory operations
379  */
380 #define F2FS_DOT_HASH		0
381 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
382 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
383 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
384 
385 typedef __le32	f2fs_hash_t;
386 
387 /* One directory entry slot covers 8bytes-long file name */
388 #define F2FS_SLOT_LEN		8
389 #define F2FS_SLOT_LEN_BITS	3
390 
391 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
392 
393 /* the number of dentry in a block */
394 #define NR_DENTRY_IN_BLOCK	214
395 
396 /* MAX level for dir lookup */
397 #define MAX_DIR_HASH_DEPTH	63
398 
399 /* MAX buckets in one level of dir */
400 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
401 
402 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
403 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
404 					BITS_PER_BYTE)
405 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
406 				F2FS_SLOT_LEN) * \
407 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
408 
409 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
410 struct f2fs_dir_entry {
411 	__le32 hash_code;	/* hash code of file name */
412 	__le32 ino;		/* inode number */
413 	__le16 name_len;	/* lengh of file name */
414 	__u8 file_type;		/* file type */
415 } __packed;
416 
417 /* 4KB-sized directory entry block */
418 struct f2fs_dentry_block {
419 	/* validity bitmap for directory entries in each block */
420 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
421 	__u8 reserved[SIZE_OF_RESERVED];
422 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
423 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
424 } __packed;
425 
426 /* file types used in inode_info->flags */
427 enum {
428 	F2FS_FT_UNKNOWN,
429 	F2FS_FT_REG_FILE,
430 	F2FS_FT_DIR,
431 	F2FS_FT_CHRDEV,
432 	F2FS_FT_BLKDEV,
433 	F2FS_FT_FIFO,
434 	F2FS_FT_SOCK,
435 	F2FS_FT_SYMLINK,
436 	F2FS_FT_MAX
437 };
438 
439 #endif  /* _LINUX_F2FS_FS_H */
440